SemaOverload.cpp revision 74d487e085c1555fb694c7ddf58315ae5e1bbecd
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 // MSVC allows implicit function to void* type conversion. 1632 if (getLangOptions().Microsoft && FromPointeeType->isFunctionType() && 1633 ToPointeeType->isVoidType()) { 1634 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1635 ToPointeeType, 1636 ToType, Context); 1637 return true; 1638 } 1639 1640 // When we're overloading in C, we allow a special kind of pointer 1641 // conversion for compatible-but-not-identical pointee types. 1642 if (!getLangOptions().CPlusPlus && 1643 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) { 1644 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1645 ToPointeeType, 1646 ToType, Context); 1647 return true; 1648 } 1649 1650 // C++ [conv.ptr]p3: 1651 // 1652 // An rvalue of type "pointer to cv D," where D is a class type, 1653 // can be converted to an rvalue of type "pointer to cv B," where 1654 // B is a base class (clause 10) of D. If B is an inaccessible 1655 // (clause 11) or ambiguous (10.2) base class of D, a program that 1656 // necessitates this conversion is ill-formed. The result of the 1657 // conversion is a pointer to the base class sub-object of the 1658 // derived class object. The null pointer value is converted to 1659 // the null pointer value of the destination type. 1660 // 1661 // Note that we do not check for ambiguity or inaccessibility 1662 // here. That is handled by CheckPointerConversion. 1663 if (getLangOptions().CPlusPlus && 1664 FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 1665 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType) && 1666 !RequireCompleteType(From->getLocStart(), FromPointeeType, PDiag()) && 1667 IsDerivedFrom(FromPointeeType, ToPointeeType)) { 1668 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1669 ToPointeeType, 1670 ToType, Context); 1671 return true; 1672 } 1673 1674 if (FromPointeeType->isVectorType() && ToPointeeType->isVectorType() && 1675 Context.areCompatibleVectorTypes(FromPointeeType, ToPointeeType)) { 1676 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1677 ToPointeeType, 1678 ToType, Context); 1679 return true; 1680 } 1681 1682 return false; 1683} 1684 1685/// \brief Adopt the given qualifiers for the given type. 1686static QualType AdoptQualifiers(ASTContext &Context, QualType T, Qualifiers Qs){ 1687 Qualifiers TQs = T.getQualifiers(); 1688 1689 // Check whether qualifiers already match. 1690 if (TQs == Qs) 1691 return T; 1692 1693 if (Qs.compatiblyIncludes(TQs)) 1694 return Context.getQualifiedType(T, Qs); 1695 1696 return Context.getQualifiedType(T.getUnqualifiedType(), Qs); 1697} 1698 1699/// isObjCPointerConversion - Determines whether this is an 1700/// Objective-C pointer conversion. Subroutine of IsPointerConversion, 1701/// with the same arguments and return values. 1702bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType, 1703 QualType& ConvertedType, 1704 bool &IncompatibleObjC) { 1705 if (!getLangOptions().ObjC1) 1706 return false; 1707 1708 // The set of qualifiers on the type we're converting from. 1709 Qualifiers FromQualifiers = FromType.getQualifiers(); 1710 1711 // First, we handle all conversions on ObjC object pointer types. 1712 const ObjCObjectPointerType* ToObjCPtr = 1713 ToType->getAs<ObjCObjectPointerType>(); 1714 const ObjCObjectPointerType *FromObjCPtr = 1715 FromType->getAs<ObjCObjectPointerType>(); 1716 1717 if (ToObjCPtr && FromObjCPtr) { 1718 // If the pointee types are the same (ignoring qualifications), 1719 // then this is not a pointer conversion. 1720 if (Context.hasSameUnqualifiedType(ToObjCPtr->getPointeeType(), 1721 FromObjCPtr->getPointeeType())) 1722 return false; 1723 1724 // Check for compatible 1725 // Objective C++: We're able to convert between "id" or "Class" and a 1726 // pointer to any interface (in both directions). 1727 if (ToObjCPtr->isObjCBuiltinType() && FromObjCPtr->isObjCBuiltinType()) { 1728 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1729 return true; 1730 } 1731 // Conversions with Objective-C's id<...>. 1732 if ((FromObjCPtr->isObjCQualifiedIdType() || 1733 ToObjCPtr->isObjCQualifiedIdType()) && 1734 Context.ObjCQualifiedIdTypesAreCompatible(ToType, FromType, 1735 /*compare=*/false)) { 1736 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1737 return true; 1738 } 1739 // Objective C++: We're able to convert from a pointer to an 1740 // interface to a pointer to a different interface. 1741 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) { 1742 const ObjCInterfaceType* LHS = ToObjCPtr->getInterfaceType(); 1743 const ObjCInterfaceType* RHS = FromObjCPtr->getInterfaceType(); 1744 if (getLangOptions().CPlusPlus && LHS && RHS && 1745 !ToObjCPtr->getPointeeType().isAtLeastAsQualifiedAs( 1746 FromObjCPtr->getPointeeType())) 1747 return false; 1748 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1749 ToObjCPtr->getPointeeType(), 1750 ToType, Context); 1751 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1752 return true; 1753 } 1754 1755 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) { 1756 // Okay: this is some kind of implicit downcast of Objective-C 1757 // interfaces, which is permitted. However, we're going to 1758 // complain about it. 1759 IncompatibleObjC = true; 1760 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1761 ToObjCPtr->getPointeeType(), 1762 ToType, Context); 1763 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1764 return true; 1765 } 1766 } 1767 // Beyond this point, both types need to be C pointers or block pointers. 1768 QualType ToPointeeType; 1769 if (const PointerType *ToCPtr = ToType->getAs<PointerType>()) 1770 ToPointeeType = ToCPtr->getPointeeType(); 1771 else if (const BlockPointerType *ToBlockPtr = 1772 ToType->getAs<BlockPointerType>()) { 1773 // Objective C++: We're able to convert from a pointer to any object 1774 // to a block pointer type. 1775 if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) { 1776 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1777 return true; 1778 } 1779 ToPointeeType = ToBlockPtr->getPointeeType(); 1780 } 1781 else if (FromType->getAs<BlockPointerType>() && 1782 ToObjCPtr && ToObjCPtr->isObjCBuiltinType()) { 1783 // Objective C++: We're able to convert from a block pointer type to a 1784 // pointer to any object. 1785 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1786 return true; 1787 } 1788 else 1789 return false; 1790 1791 QualType FromPointeeType; 1792 if (const PointerType *FromCPtr = FromType->getAs<PointerType>()) 1793 FromPointeeType = FromCPtr->getPointeeType(); 1794 else if (const BlockPointerType *FromBlockPtr = 1795 FromType->getAs<BlockPointerType>()) 1796 FromPointeeType = FromBlockPtr->getPointeeType(); 1797 else 1798 return false; 1799 1800 // If we have pointers to pointers, recursively check whether this 1801 // is an Objective-C conversion. 1802 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() && 1803 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1804 IncompatibleObjC)) { 1805 // We always complain about this conversion. 1806 IncompatibleObjC = true; 1807 ConvertedType = Context.getPointerType(ConvertedType); 1808 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1809 return true; 1810 } 1811 // Allow conversion of pointee being objective-c pointer to another one; 1812 // as in I* to id. 1813 if (FromPointeeType->getAs<ObjCObjectPointerType>() && 1814 ToPointeeType->getAs<ObjCObjectPointerType>() && 1815 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1816 IncompatibleObjC)) { 1817 ConvertedType = Context.getPointerType(ConvertedType); 1818 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1819 return true; 1820 } 1821 1822 // If we have pointers to functions or blocks, check whether the only 1823 // differences in the argument and result types are in Objective-C 1824 // pointer conversions. If so, we permit the conversion (but 1825 // complain about it). 1826 const FunctionProtoType *FromFunctionType 1827 = FromPointeeType->getAs<FunctionProtoType>(); 1828 const FunctionProtoType *ToFunctionType 1829 = ToPointeeType->getAs<FunctionProtoType>(); 1830 if (FromFunctionType && ToFunctionType) { 1831 // If the function types are exactly the same, this isn't an 1832 // Objective-C pointer conversion. 1833 if (Context.getCanonicalType(FromPointeeType) 1834 == Context.getCanonicalType(ToPointeeType)) 1835 return false; 1836 1837 // Perform the quick checks that will tell us whether these 1838 // function types are obviously different. 1839 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 1840 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() || 1841 FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals()) 1842 return false; 1843 1844 bool HasObjCConversion = false; 1845 if (Context.getCanonicalType(FromFunctionType->getResultType()) 1846 == Context.getCanonicalType(ToFunctionType->getResultType())) { 1847 // Okay, the types match exactly. Nothing to do. 1848 } else if (isObjCPointerConversion(FromFunctionType->getResultType(), 1849 ToFunctionType->getResultType(), 1850 ConvertedType, IncompatibleObjC)) { 1851 // Okay, we have an Objective-C pointer conversion. 1852 HasObjCConversion = true; 1853 } else { 1854 // Function types are too different. Abort. 1855 return false; 1856 } 1857 1858 // Check argument types. 1859 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 1860 ArgIdx != NumArgs; ++ArgIdx) { 1861 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 1862 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 1863 if (Context.getCanonicalType(FromArgType) 1864 == Context.getCanonicalType(ToArgType)) { 1865 // Okay, the types match exactly. Nothing to do. 1866 } else if (isObjCPointerConversion(FromArgType, ToArgType, 1867 ConvertedType, IncompatibleObjC)) { 1868 // Okay, we have an Objective-C pointer conversion. 1869 HasObjCConversion = true; 1870 } else { 1871 // Argument types are too different. Abort. 1872 return false; 1873 } 1874 } 1875 1876 if (HasObjCConversion) { 1877 // We had an Objective-C conversion. Allow this pointer 1878 // conversion, but complain about it. 1879 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1880 IncompatibleObjC = true; 1881 return true; 1882 } 1883 } 1884 1885 return false; 1886} 1887 1888bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType, 1889 QualType& ConvertedType) { 1890 QualType ToPointeeType; 1891 if (const BlockPointerType *ToBlockPtr = 1892 ToType->getAs<BlockPointerType>()) 1893 ToPointeeType = ToBlockPtr->getPointeeType(); 1894 else 1895 return false; 1896 1897 QualType FromPointeeType; 1898 if (const BlockPointerType *FromBlockPtr = 1899 FromType->getAs<BlockPointerType>()) 1900 FromPointeeType = FromBlockPtr->getPointeeType(); 1901 else 1902 return false; 1903 // We have pointer to blocks, check whether the only 1904 // differences in the argument and result types are in Objective-C 1905 // pointer conversions. If so, we permit the conversion. 1906 1907 const FunctionProtoType *FromFunctionType 1908 = FromPointeeType->getAs<FunctionProtoType>(); 1909 const FunctionProtoType *ToFunctionType 1910 = ToPointeeType->getAs<FunctionProtoType>(); 1911 1912 if (!FromFunctionType || !ToFunctionType) 1913 return false; 1914 1915 if (Context.hasSameType(FromPointeeType, ToPointeeType)) 1916 return true; 1917 1918 // Perform the quick checks that will tell us whether these 1919 // function types are obviously different. 1920 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 1921 FromFunctionType->isVariadic() != ToFunctionType->isVariadic()) 1922 return false; 1923 1924 FunctionType::ExtInfo FromEInfo = FromFunctionType->getExtInfo(); 1925 FunctionType::ExtInfo ToEInfo = ToFunctionType->getExtInfo(); 1926 if (FromEInfo != ToEInfo) 1927 return false; 1928 1929 bool IncompatibleObjC = false; 1930 if (Context.hasSameType(FromFunctionType->getResultType(), 1931 ToFunctionType->getResultType())) { 1932 // Okay, the types match exactly. Nothing to do. 1933 } else { 1934 QualType RHS = FromFunctionType->getResultType(); 1935 QualType LHS = ToFunctionType->getResultType(); 1936 if ((!getLangOptions().CPlusPlus || !RHS->isRecordType()) && 1937 !RHS.hasQualifiers() && LHS.hasQualifiers()) 1938 LHS = LHS.getUnqualifiedType(); 1939 1940 if (Context.hasSameType(RHS,LHS)) { 1941 // OK exact match. 1942 } else if (isObjCPointerConversion(RHS, LHS, 1943 ConvertedType, IncompatibleObjC)) { 1944 if (IncompatibleObjC) 1945 return false; 1946 // Okay, we have an Objective-C pointer conversion. 1947 } 1948 else 1949 return false; 1950 } 1951 1952 // Check argument types. 1953 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 1954 ArgIdx != NumArgs; ++ArgIdx) { 1955 IncompatibleObjC = false; 1956 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 1957 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 1958 if (Context.hasSameType(FromArgType, ToArgType)) { 1959 // Okay, the types match exactly. Nothing to do. 1960 } else if (isObjCPointerConversion(ToArgType, FromArgType, 1961 ConvertedType, IncompatibleObjC)) { 1962 if (IncompatibleObjC) 1963 return false; 1964 // Okay, we have an Objective-C pointer conversion. 1965 } else 1966 // Argument types are too different. Abort. 1967 return false; 1968 } 1969 ConvertedType = ToType; 1970 return true; 1971} 1972 1973/// FunctionArgTypesAreEqual - This routine checks two function proto types 1974/// for equlity of their argument types. Caller has already checked that 1975/// they have same number of arguments. This routine assumes that Objective-C 1976/// pointer types which only differ in their protocol qualifiers are equal. 1977bool Sema::FunctionArgTypesAreEqual(const FunctionProtoType *OldType, 1978 const FunctionProtoType *NewType) { 1979 if (!getLangOptions().ObjC1) 1980 return std::equal(OldType->arg_type_begin(), OldType->arg_type_end(), 1981 NewType->arg_type_begin()); 1982 1983 for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(), 1984 N = NewType->arg_type_begin(), 1985 E = OldType->arg_type_end(); O && (O != E); ++O, ++N) { 1986 QualType ToType = (*O); 1987 QualType FromType = (*N); 1988 if (ToType != FromType) { 1989 if (const PointerType *PTTo = ToType->getAs<PointerType>()) { 1990 if (const PointerType *PTFr = FromType->getAs<PointerType>()) 1991 if ((PTTo->getPointeeType()->isObjCQualifiedIdType() && 1992 PTFr->getPointeeType()->isObjCQualifiedIdType()) || 1993 (PTTo->getPointeeType()->isObjCQualifiedClassType() && 1994 PTFr->getPointeeType()->isObjCQualifiedClassType())) 1995 continue; 1996 } 1997 else if (const ObjCObjectPointerType *PTTo = 1998 ToType->getAs<ObjCObjectPointerType>()) { 1999 if (const ObjCObjectPointerType *PTFr = 2000 FromType->getAs<ObjCObjectPointerType>()) 2001 if (PTTo->getInterfaceDecl() == PTFr->getInterfaceDecl()) 2002 continue; 2003 } 2004 return false; 2005 } 2006 } 2007 return true; 2008} 2009 2010/// CheckPointerConversion - Check the pointer conversion from the 2011/// expression From to the type ToType. This routine checks for 2012/// ambiguous or inaccessible derived-to-base pointer 2013/// conversions for which IsPointerConversion has already returned 2014/// true. It returns true and produces a diagnostic if there was an 2015/// error, or returns false otherwise. 2016bool Sema::CheckPointerConversion(Expr *From, QualType ToType, 2017 CastKind &Kind, 2018 CXXCastPath& BasePath, 2019 bool IgnoreBaseAccess) { 2020 QualType FromType = From->getType(); 2021 bool IsCStyleOrFunctionalCast = IgnoreBaseAccess; 2022 2023 Kind = CK_BitCast; 2024 2025 if (!IsCStyleOrFunctionalCast && 2026 Context.hasSameUnqualifiedType(From->getType(), Context.BoolTy) && 2027 From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 2028 DiagRuntimeBehavior(From->getExprLoc(), From, 2029 PDiag(diag::warn_impcast_bool_to_null_pointer) 2030 << ToType << From->getSourceRange()); 2031 2032 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) 2033 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) { 2034 QualType FromPointeeType = FromPtrType->getPointeeType(), 2035 ToPointeeType = ToPtrType->getPointeeType(); 2036 2037 if (FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 2038 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) { 2039 // We must have a derived-to-base conversion. Check an 2040 // ambiguous or inaccessible conversion. 2041 if (CheckDerivedToBaseConversion(FromPointeeType, ToPointeeType, 2042 From->getExprLoc(), 2043 From->getSourceRange(), &BasePath, 2044 IgnoreBaseAccess)) 2045 return true; 2046 2047 // The conversion was successful. 2048 Kind = CK_DerivedToBase; 2049 } 2050 } 2051 if (const ObjCObjectPointerType *FromPtrType = 2052 FromType->getAs<ObjCObjectPointerType>()) { 2053 if (const ObjCObjectPointerType *ToPtrType = 2054 ToType->getAs<ObjCObjectPointerType>()) { 2055 // Objective-C++ conversions are always okay. 2056 // FIXME: We should have a different class of conversions for the 2057 // Objective-C++ implicit conversions. 2058 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType()) 2059 return false; 2060 } 2061 } 2062 2063 // We shouldn't fall into this case unless it's valid for other 2064 // reasons. 2065 if (From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 2066 Kind = CK_NullToPointer; 2067 2068 return false; 2069} 2070 2071/// IsMemberPointerConversion - Determines whether the conversion of the 2072/// expression From, which has the (possibly adjusted) type FromType, can be 2073/// converted to the type ToType via a member pointer conversion (C++ 4.11). 2074/// If so, returns true and places the converted type (that might differ from 2075/// ToType in its cv-qualifiers at some level) into ConvertedType. 2076bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType, 2077 QualType ToType, 2078 bool InOverloadResolution, 2079 QualType &ConvertedType) { 2080 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>(); 2081 if (!ToTypePtr) 2082 return false; 2083 2084 // A null pointer constant can be converted to a member pointer (C++ 4.11p1) 2085 if (From->isNullPointerConstant(Context, 2086 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 2087 : Expr::NPC_ValueDependentIsNull)) { 2088 ConvertedType = ToType; 2089 return true; 2090 } 2091 2092 // Otherwise, both types have to be member pointers. 2093 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>(); 2094 if (!FromTypePtr) 2095 return false; 2096 2097 // A pointer to member of B can be converted to a pointer to member of D, 2098 // where D is derived from B (C++ 4.11p2). 2099 QualType FromClass(FromTypePtr->getClass(), 0); 2100 QualType ToClass(ToTypePtr->getClass(), 0); 2101 2102 if (!Context.hasSameUnqualifiedType(FromClass, ToClass) && 2103 !RequireCompleteType(From->getLocStart(), ToClass, PDiag()) && 2104 IsDerivedFrom(ToClass, FromClass)) { 2105 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(), 2106 ToClass.getTypePtr()); 2107 return true; 2108 } 2109 2110 return false; 2111} 2112 2113/// CheckMemberPointerConversion - Check the member pointer conversion from the 2114/// expression From to the type ToType. This routine checks for ambiguous or 2115/// virtual or inaccessible base-to-derived member pointer conversions 2116/// for which IsMemberPointerConversion has already returned true. It returns 2117/// true and produces a diagnostic if there was an error, or returns false 2118/// otherwise. 2119bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType, 2120 CastKind &Kind, 2121 CXXCastPath &BasePath, 2122 bool IgnoreBaseAccess) { 2123 QualType FromType = From->getType(); 2124 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>(); 2125 if (!FromPtrType) { 2126 // This must be a null pointer to member pointer conversion 2127 assert(From->isNullPointerConstant(Context, 2128 Expr::NPC_ValueDependentIsNull) && 2129 "Expr must be null pointer constant!"); 2130 Kind = CK_NullToMemberPointer; 2131 return false; 2132 } 2133 2134 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>(); 2135 assert(ToPtrType && "No member pointer cast has a target type " 2136 "that is not a member pointer."); 2137 2138 QualType FromClass = QualType(FromPtrType->getClass(), 0); 2139 QualType ToClass = QualType(ToPtrType->getClass(), 0); 2140 2141 // FIXME: What about dependent types? 2142 assert(FromClass->isRecordType() && "Pointer into non-class."); 2143 assert(ToClass->isRecordType() && "Pointer into non-class."); 2144 2145 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 2146 /*DetectVirtual=*/true); 2147 bool DerivationOkay = IsDerivedFrom(ToClass, FromClass, Paths); 2148 assert(DerivationOkay && 2149 "Should not have been called if derivation isn't OK."); 2150 (void)DerivationOkay; 2151 2152 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass). 2153 getUnqualifiedType())) { 2154 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths); 2155 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv) 2156 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange(); 2157 return true; 2158 } 2159 2160 if (const RecordType *VBase = Paths.getDetectedVirtual()) { 2161 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual) 2162 << FromClass << ToClass << QualType(VBase, 0) 2163 << From->getSourceRange(); 2164 return true; 2165 } 2166 2167 if (!IgnoreBaseAccess) 2168 CheckBaseClassAccess(From->getExprLoc(), FromClass, ToClass, 2169 Paths.front(), 2170 diag::err_downcast_from_inaccessible_base); 2171 2172 // Must be a base to derived member conversion. 2173 BuildBasePathArray(Paths, BasePath); 2174 Kind = CK_BaseToDerivedMemberPointer; 2175 return false; 2176} 2177 2178/// IsQualificationConversion - Determines whether the conversion from 2179/// an rvalue of type FromType to ToType is a qualification conversion 2180/// (C++ 4.4). 2181bool 2182Sema::IsQualificationConversion(QualType FromType, QualType ToType, 2183 bool CStyle) { 2184 FromType = Context.getCanonicalType(FromType); 2185 ToType = Context.getCanonicalType(ToType); 2186 2187 // If FromType and ToType are the same type, this is not a 2188 // qualification conversion. 2189 if (FromType.getUnqualifiedType() == ToType.getUnqualifiedType()) 2190 return false; 2191 2192 // (C++ 4.4p4): 2193 // A conversion can add cv-qualifiers at levels other than the first 2194 // in multi-level pointers, subject to the following rules: [...] 2195 bool PreviousToQualsIncludeConst = true; 2196 bool UnwrappedAnyPointer = false; 2197 while (Context.UnwrapSimilarPointerTypes(FromType, ToType)) { 2198 // Within each iteration of the loop, we check the qualifiers to 2199 // determine if this still looks like a qualification 2200 // conversion. Then, if all is well, we unwrap one more level of 2201 // pointers or pointers-to-members and do it all again 2202 // until there are no more pointers or pointers-to-members left to 2203 // unwrap. 2204 UnwrappedAnyPointer = true; 2205 2206 Qualifiers FromQuals = FromType.getQualifiers(); 2207 Qualifiers ToQuals = ToType.getQualifiers(); 2208 2209 // Allow addition/removal of GC attributes but not changing GC attributes. 2210 if (FromQuals.getObjCGCAttr() != ToQuals.getObjCGCAttr() && 2211 (!FromQuals.hasObjCGCAttr() || !ToQuals.hasObjCGCAttr())) { 2212 FromQuals.removeObjCGCAttr(); 2213 ToQuals.removeObjCGCAttr(); 2214 } 2215 2216 // -- for every j > 0, if const is in cv 1,j then const is in cv 2217 // 2,j, and similarly for volatile. 2218 if (!CStyle && !ToQuals.compatiblyIncludes(FromQuals)) 2219 return false; 2220 2221 // -- if the cv 1,j and cv 2,j are different, then const is in 2222 // every cv for 0 < k < j. 2223 if (!CStyle && FromQuals.getCVRQualifiers() != ToQuals.getCVRQualifiers() 2224 && !PreviousToQualsIncludeConst) 2225 return false; 2226 2227 // Keep track of whether all prior cv-qualifiers in the "to" type 2228 // include const. 2229 PreviousToQualsIncludeConst 2230 = PreviousToQualsIncludeConst && ToQuals.hasConst(); 2231 } 2232 2233 // We are left with FromType and ToType being the pointee types 2234 // after unwrapping the original FromType and ToType the same number 2235 // of types. If we unwrapped any pointers, and if FromType and 2236 // ToType have the same unqualified type (since we checked 2237 // qualifiers above), then this is a qualification conversion. 2238 return UnwrappedAnyPointer && Context.hasSameUnqualifiedType(FromType,ToType); 2239} 2240 2241/// Determines whether there is a user-defined conversion sequence 2242/// (C++ [over.ics.user]) that converts expression From to the type 2243/// ToType. If such a conversion exists, User will contain the 2244/// user-defined conversion sequence that performs such a conversion 2245/// and this routine will return true. Otherwise, this routine returns 2246/// false and User is unspecified. 2247/// 2248/// \param AllowExplicit true if the conversion should consider C++0x 2249/// "explicit" conversion functions as well as non-explicit conversion 2250/// functions (C++0x [class.conv.fct]p2). 2251static OverloadingResult 2252IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 2253 UserDefinedConversionSequence& User, 2254 OverloadCandidateSet& CandidateSet, 2255 bool AllowExplicit) { 2256 // Whether we will only visit constructors. 2257 bool ConstructorsOnly = false; 2258 2259 // If the type we are conversion to is a class type, enumerate its 2260 // constructors. 2261 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) { 2262 // C++ [over.match.ctor]p1: 2263 // When objects of class type are direct-initialized (8.5), or 2264 // copy-initialized from an expression of the same or a 2265 // derived class type (8.5), overload resolution selects the 2266 // constructor. [...] For copy-initialization, the candidate 2267 // functions are all the converting constructors (12.3.1) of 2268 // that class. The argument list is the expression-list within 2269 // the parentheses of the initializer. 2270 if (S.Context.hasSameUnqualifiedType(ToType, From->getType()) || 2271 (From->getType()->getAs<RecordType>() && 2272 S.IsDerivedFrom(From->getType(), ToType))) 2273 ConstructorsOnly = true; 2274 2275 S.RequireCompleteType(From->getLocStart(), ToType, S.PDiag()); 2276 // RequireCompleteType may have returned true due to some invalid decl 2277 // during template instantiation, but ToType may be complete enough now 2278 // to try to recover. 2279 if (ToType->isIncompleteType()) { 2280 // We're not going to find any constructors. 2281 } else if (CXXRecordDecl *ToRecordDecl 2282 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) { 2283 DeclContext::lookup_iterator Con, ConEnd; 2284 for (llvm::tie(Con, ConEnd) = S.LookupConstructors(ToRecordDecl); 2285 Con != ConEnd; ++Con) { 2286 NamedDecl *D = *Con; 2287 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2288 2289 // Find the constructor (which may be a template). 2290 CXXConstructorDecl *Constructor = 0; 2291 FunctionTemplateDecl *ConstructorTmpl 2292 = dyn_cast<FunctionTemplateDecl>(D); 2293 if (ConstructorTmpl) 2294 Constructor 2295 = cast<CXXConstructorDecl>(ConstructorTmpl->getTemplatedDecl()); 2296 else 2297 Constructor = cast<CXXConstructorDecl>(D); 2298 2299 if (!Constructor->isInvalidDecl() && 2300 Constructor->isConvertingConstructor(AllowExplicit)) { 2301 if (ConstructorTmpl) 2302 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2303 /*ExplicitArgs*/ 0, 2304 &From, 1, CandidateSet, 2305 /*SuppressUserConversions=*/ 2306 !ConstructorsOnly); 2307 else 2308 // Allow one user-defined conversion when user specifies a 2309 // From->ToType conversion via an static cast (c-style, etc). 2310 S.AddOverloadCandidate(Constructor, FoundDecl, 2311 &From, 1, CandidateSet, 2312 /*SuppressUserConversions=*/ 2313 !ConstructorsOnly); 2314 } 2315 } 2316 } 2317 } 2318 2319 // Enumerate conversion functions, if we're allowed to. 2320 if (ConstructorsOnly) { 2321 } else if (S.RequireCompleteType(From->getLocStart(), From->getType(), 2322 S.PDiag(0) << From->getSourceRange())) { 2323 // No conversion functions from incomplete types. 2324 } else if (const RecordType *FromRecordType 2325 = From->getType()->getAs<RecordType>()) { 2326 if (CXXRecordDecl *FromRecordDecl 2327 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) { 2328 // Add all of the conversion functions as candidates. 2329 const UnresolvedSetImpl *Conversions 2330 = FromRecordDecl->getVisibleConversionFunctions(); 2331 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 2332 E = Conversions->end(); I != E; ++I) { 2333 DeclAccessPair FoundDecl = I.getPair(); 2334 NamedDecl *D = FoundDecl.getDecl(); 2335 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 2336 if (isa<UsingShadowDecl>(D)) 2337 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2338 2339 CXXConversionDecl *Conv; 2340 FunctionTemplateDecl *ConvTemplate; 2341 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D))) 2342 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2343 else 2344 Conv = cast<CXXConversionDecl>(D); 2345 2346 if (AllowExplicit || !Conv->isExplicit()) { 2347 if (ConvTemplate) 2348 S.AddTemplateConversionCandidate(ConvTemplate, FoundDecl, 2349 ActingContext, From, ToType, 2350 CandidateSet); 2351 else 2352 S.AddConversionCandidate(Conv, FoundDecl, ActingContext, 2353 From, ToType, CandidateSet); 2354 } 2355 } 2356 } 2357 } 2358 2359 OverloadCandidateSet::iterator Best; 2360 switch (CandidateSet.BestViableFunction(S, From->getLocStart(), Best, true)) { 2361 case OR_Success: 2362 // Record the standard conversion we used and the conversion function. 2363 if (CXXConstructorDecl *Constructor 2364 = dyn_cast<CXXConstructorDecl>(Best->Function)) { 2365 S.MarkDeclarationReferenced(From->getLocStart(), Constructor); 2366 2367 // C++ [over.ics.user]p1: 2368 // If the user-defined conversion is specified by a 2369 // constructor (12.3.1), the initial standard conversion 2370 // sequence converts the source type to the type required by 2371 // the argument of the constructor. 2372 // 2373 QualType ThisType = Constructor->getThisType(S.Context); 2374 if (Best->Conversions[0].isEllipsis()) 2375 User.EllipsisConversion = true; 2376 else { 2377 User.Before = Best->Conversions[0].Standard; 2378 User.EllipsisConversion = false; 2379 } 2380 User.ConversionFunction = Constructor; 2381 User.FoundConversionFunction = Best->FoundDecl.getDecl(); 2382 User.After.setAsIdentityConversion(); 2383 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType()); 2384 User.After.setAllToTypes(ToType); 2385 return OR_Success; 2386 } else if (CXXConversionDecl *Conversion 2387 = dyn_cast<CXXConversionDecl>(Best->Function)) { 2388 S.MarkDeclarationReferenced(From->getLocStart(), Conversion); 2389 2390 // C++ [over.ics.user]p1: 2391 // 2392 // [...] If the user-defined conversion is specified by a 2393 // conversion function (12.3.2), the initial standard 2394 // conversion sequence converts the source type to the 2395 // implicit object parameter of the conversion function. 2396 User.Before = Best->Conversions[0].Standard; 2397 User.ConversionFunction = Conversion; 2398 User.FoundConversionFunction = Best->FoundDecl.getDecl(); 2399 User.EllipsisConversion = false; 2400 2401 // C++ [over.ics.user]p2: 2402 // The second standard conversion sequence converts the 2403 // result of the user-defined conversion to the target type 2404 // for the sequence. Since an implicit conversion sequence 2405 // is an initialization, the special rules for 2406 // initialization by user-defined conversion apply when 2407 // selecting the best user-defined conversion for a 2408 // user-defined conversion sequence (see 13.3.3 and 2409 // 13.3.3.1). 2410 User.After = Best->FinalConversion; 2411 return OR_Success; 2412 } else { 2413 llvm_unreachable("Not a constructor or conversion function?"); 2414 return OR_No_Viable_Function; 2415 } 2416 2417 case OR_No_Viable_Function: 2418 return OR_No_Viable_Function; 2419 case OR_Deleted: 2420 // No conversion here! We're done. 2421 return OR_Deleted; 2422 2423 case OR_Ambiguous: 2424 return OR_Ambiguous; 2425 } 2426 2427 return OR_No_Viable_Function; 2428} 2429 2430bool 2431Sema::DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType) { 2432 ImplicitConversionSequence ICS; 2433 OverloadCandidateSet CandidateSet(From->getExprLoc()); 2434 OverloadingResult OvResult = 2435 IsUserDefinedConversion(*this, From, ToType, ICS.UserDefined, 2436 CandidateSet, false); 2437 if (OvResult == OR_Ambiguous) 2438 Diag(From->getSourceRange().getBegin(), 2439 diag::err_typecheck_ambiguous_condition) 2440 << From->getType() << ToType << From->getSourceRange(); 2441 else if (OvResult == OR_No_Viable_Function && !CandidateSet.empty()) 2442 Diag(From->getSourceRange().getBegin(), 2443 diag::err_typecheck_nonviable_condition) 2444 << From->getType() << ToType << From->getSourceRange(); 2445 else 2446 return false; 2447 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &From, 1); 2448 return true; 2449} 2450 2451/// CompareImplicitConversionSequences - Compare two implicit 2452/// conversion sequences to determine whether one is better than the 2453/// other or if they are indistinguishable (C++ 13.3.3.2). 2454static ImplicitConversionSequence::CompareKind 2455CompareImplicitConversionSequences(Sema &S, 2456 const ImplicitConversionSequence& ICS1, 2457 const ImplicitConversionSequence& ICS2) 2458{ 2459 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit 2460 // conversion sequences (as defined in 13.3.3.1) 2461 // -- a standard conversion sequence (13.3.3.1.1) is a better 2462 // conversion sequence than a user-defined conversion sequence or 2463 // an ellipsis conversion sequence, and 2464 // -- a user-defined conversion sequence (13.3.3.1.2) is a better 2465 // conversion sequence than an ellipsis conversion sequence 2466 // (13.3.3.1.3). 2467 // 2468 // C++0x [over.best.ics]p10: 2469 // For the purpose of ranking implicit conversion sequences as 2470 // described in 13.3.3.2, the ambiguous conversion sequence is 2471 // treated as a user-defined sequence that is indistinguishable 2472 // from any other user-defined conversion sequence. 2473 if (ICS1.getKindRank() < ICS2.getKindRank()) 2474 return ImplicitConversionSequence::Better; 2475 else if (ICS2.getKindRank() < ICS1.getKindRank()) 2476 return ImplicitConversionSequence::Worse; 2477 2478 // The following checks require both conversion sequences to be of 2479 // the same kind. 2480 if (ICS1.getKind() != ICS2.getKind()) 2481 return ImplicitConversionSequence::Indistinguishable; 2482 2483 // Two implicit conversion sequences of the same form are 2484 // indistinguishable conversion sequences unless one of the 2485 // following rules apply: (C++ 13.3.3.2p3): 2486 if (ICS1.isStandard()) 2487 return CompareStandardConversionSequences(S, ICS1.Standard, ICS2.Standard); 2488 else if (ICS1.isUserDefined()) { 2489 // User-defined conversion sequence U1 is a better conversion 2490 // sequence than another user-defined conversion sequence U2 if 2491 // they contain the same user-defined conversion function or 2492 // constructor and if the second standard conversion sequence of 2493 // U1 is better than the second standard conversion sequence of 2494 // U2 (C++ 13.3.3.2p3). 2495 if (ICS1.UserDefined.ConversionFunction == 2496 ICS2.UserDefined.ConversionFunction) 2497 return CompareStandardConversionSequences(S, 2498 ICS1.UserDefined.After, 2499 ICS2.UserDefined.After); 2500 } 2501 2502 return ImplicitConversionSequence::Indistinguishable; 2503} 2504 2505static bool hasSimilarType(ASTContext &Context, QualType T1, QualType T2) { 2506 while (Context.UnwrapSimilarPointerTypes(T1, T2)) { 2507 Qualifiers Quals; 2508 T1 = Context.getUnqualifiedArrayType(T1, Quals); 2509 T2 = Context.getUnqualifiedArrayType(T2, Quals); 2510 } 2511 2512 return Context.hasSameUnqualifiedType(T1, T2); 2513} 2514 2515// Per 13.3.3.2p3, compare the given standard conversion sequences to 2516// determine if one is a proper subset of the other. 2517static ImplicitConversionSequence::CompareKind 2518compareStandardConversionSubsets(ASTContext &Context, 2519 const StandardConversionSequence& SCS1, 2520 const StandardConversionSequence& SCS2) { 2521 ImplicitConversionSequence::CompareKind Result 2522 = ImplicitConversionSequence::Indistinguishable; 2523 2524 // the identity conversion sequence is considered to be a subsequence of 2525 // any non-identity conversion sequence 2526 if (SCS1.isIdentityConversion() && !SCS2.isIdentityConversion()) 2527 return ImplicitConversionSequence::Better; 2528 else if (!SCS1.isIdentityConversion() && SCS2.isIdentityConversion()) 2529 return ImplicitConversionSequence::Worse; 2530 2531 if (SCS1.Second != SCS2.Second) { 2532 if (SCS1.Second == ICK_Identity) 2533 Result = ImplicitConversionSequence::Better; 2534 else if (SCS2.Second == ICK_Identity) 2535 Result = ImplicitConversionSequence::Worse; 2536 else 2537 return ImplicitConversionSequence::Indistinguishable; 2538 } else if (!hasSimilarType(Context, SCS1.getToType(1), SCS2.getToType(1))) 2539 return ImplicitConversionSequence::Indistinguishable; 2540 2541 if (SCS1.Third == SCS2.Third) { 2542 return Context.hasSameType(SCS1.getToType(2), SCS2.getToType(2))? Result 2543 : ImplicitConversionSequence::Indistinguishable; 2544 } 2545 2546 if (SCS1.Third == ICK_Identity) 2547 return Result == ImplicitConversionSequence::Worse 2548 ? ImplicitConversionSequence::Indistinguishable 2549 : ImplicitConversionSequence::Better; 2550 2551 if (SCS2.Third == ICK_Identity) 2552 return Result == ImplicitConversionSequence::Better 2553 ? ImplicitConversionSequence::Indistinguishable 2554 : ImplicitConversionSequence::Worse; 2555 2556 return ImplicitConversionSequence::Indistinguishable; 2557} 2558 2559/// \brief Determine whether one of the given reference bindings is better 2560/// than the other based on what kind of bindings they are. 2561static bool isBetterReferenceBindingKind(const StandardConversionSequence &SCS1, 2562 const StandardConversionSequence &SCS2) { 2563 // C++0x [over.ics.rank]p3b4: 2564 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an 2565 // implicit object parameter of a non-static member function declared 2566 // without a ref-qualifier, and *either* S1 binds an rvalue reference 2567 // to an rvalue and S2 binds an lvalue reference *or S1 binds an 2568 // lvalue reference to a function lvalue and S2 binds an rvalue 2569 // reference*. 2570 // 2571 // FIXME: Rvalue references. We're going rogue with the above edits, 2572 // because the semantics in the current C++0x working paper (N3225 at the 2573 // time of this writing) break the standard definition of std::forward 2574 // and std::reference_wrapper when dealing with references to functions. 2575 // Proposed wording changes submitted to CWG for consideration. 2576 if (SCS1.BindsImplicitObjectArgumentWithoutRefQualifier || 2577 SCS2.BindsImplicitObjectArgumentWithoutRefQualifier) 2578 return false; 2579 2580 return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue && 2581 SCS2.IsLvalueReference) || 2582 (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue && 2583 !SCS2.IsLvalueReference); 2584} 2585 2586/// CompareStandardConversionSequences - Compare two standard 2587/// conversion sequences to determine whether one is better than the 2588/// other or if they are indistinguishable (C++ 13.3.3.2p3). 2589static ImplicitConversionSequence::CompareKind 2590CompareStandardConversionSequences(Sema &S, 2591 const StandardConversionSequence& SCS1, 2592 const StandardConversionSequence& SCS2) 2593{ 2594 // Standard conversion sequence S1 is a better conversion sequence 2595 // than standard conversion sequence S2 if (C++ 13.3.3.2p3): 2596 2597 // -- S1 is a proper subsequence of S2 (comparing the conversion 2598 // sequences in the canonical form defined by 13.3.3.1.1, 2599 // excluding any Lvalue Transformation; the identity conversion 2600 // sequence is considered to be a subsequence of any 2601 // non-identity conversion sequence) or, if not that, 2602 if (ImplicitConversionSequence::CompareKind CK 2603 = compareStandardConversionSubsets(S.Context, SCS1, SCS2)) 2604 return CK; 2605 2606 // -- the rank of S1 is better than the rank of S2 (by the rules 2607 // defined below), or, if not that, 2608 ImplicitConversionRank Rank1 = SCS1.getRank(); 2609 ImplicitConversionRank Rank2 = SCS2.getRank(); 2610 if (Rank1 < Rank2) 2611 return ImplicitConversionSequence::Better; 2612 else if (Rank2 < Rank1) 2613 return ImplicitConversionSequence::Worse; 2614 2615 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank 2616 // are indistinguishable unless one of the following rules 2617 // applies: 2618 2619 // A conversion that is not a conversion of a pointer, or 2620 // pointer to member, to bool is better than another conversion 2621 // that is such a conversion. 2622 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool()) 2623 return SCS2.isPointerConversionToBool() 2624 ? ImplicitConversionSequence::Better 2625 : ImplicitConversionSequence::Worse; 2626 2627 // C++ [over.ics.rank]p4b2: 2628 // 2629 // If class B is derived directly or indirectly from class A, 2630 // conversion of B* to A* is better than conversion of B* to 2631 // void*, and conversion of A* to void* is better than conversion 2632 // of B* to void*. 2633 bool SCS1ConvertsToVoid 2634 = SCS1.isPointerConversionToVoidPointer(S.Context); 2635 bool SCS2ConvertsToVoid 2636 = SCS2.isPointerConversionToVoidPointer(S.Context); 2637 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) { 2638 // Exactly one of the conversion sequences is a conversion to 2639 // a void pointer; it's the worse conversion. 2640 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better 2641 : ImplicitConversionSequence::Worse; 2642 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) { 2643 // Neither conversion sequence converts to a void pointer; compare 2644 // their derived-to-base conversions. 2645 if (ImplicitConversionSequence::CompareKind DerivedCK 2646 = CompareDerivedToBaseConversions(S, SCS1, SCS2)) 2647 return DerivedCK; 2648 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid && 2649 !S.Context.hasSameType(SCS1.getFromType(), SCS2.getFromType())) { 2650 // Both conversion sequences are conversions to void 2651 // pointers. Compare the source types to determine if there's an 2652 // inheritance relationship in their sources. 2653 QualType FromType1 = SCS1.getFromType(); 2654 QualType FromType2 = SCS2.getFromType(); 2655 2656 // Adjust the types we're converting from via the array-to-pointer 2657 // conversion, if we need to. 2658 if (SCS1.First == ICK_Array_To_Pointer) 2659 FromType1 = S.Context.getArrayDecayedType(FromType1); 2660 if (SCS2.First == ICK_Array_To_Pointer) 2661 FromType2 = S.Context.getArrayDecayedType(FromType2); 2662 2663 QualType FromPointee1 = FromType1->getPointeeType().getUnqualifiedType(); 2664 QualType FromPointee2 = FromType2->getPointeeType().getUnqualifiedType(); 2665 2666 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 2667 return ImplicitConversionSequence::Better; 2668 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 2669 return ImplicitConversionSequence::Worse; 2670 2671 // Objective-C++: If one interface is more specific than the 2672 // other, it is the better one. 2673 const ObjCObjectPointerType* FromObjCPtr1 2674 = FromType1->getAs<ObjCObjectPointerType>(); 2675 const ObjCObjectPointerType* FromObjCPtr2 2676 = FromType2->getAs<ObjCObjectPointerType>(); 2677 if (FromObjCPtr1 && FromObjCPtr2) { 2678 bool AssignLeft = S.Context.canAssignObjCInterfaces(FromObjCPtr1, 2679 FromObjCPtr2); 2680 bool AssignRight = S.Context.canAssignObjCInterfaces(FromObjCPtr2, 2681 FromObjCPtr1); 2682 if (AssignLeft != AssignRight) { 2683 return AssignLeft? ImplicitConversionSequence::Better 2684 : ImplicitConversionSequence::Worse; 2685 } 2686 } 2687 } 2688 2689 // Compare based on qualification conversions (C++ 13.3.3.2p3, 2690 // bullet 3). 2691 if (ImplicitConversionSequence::CompareKind QualCK 2692 = CompareQualificationConversions(S, SCS1, SCS2)) 2693 return QualCK; 2694 2695 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) { 2696 // Check for a better reference binding based on the kind of bindings. 2697 if (isBetterReferenceBindingKind(SCS1, SCS2)) 2698 return ImplicitConversionSequence::Better; 2699 else if (isBetterReferenceBindingKind(SCS2, SCS1)) 2700 return ImplicitConversionSequence::Worse; 2701 2702 // C++ [over.ics.rank]p3b4: 2703 // -- S1 and S2 are reference bindings (8.5.3), and the types to 2704 // which the references refer are the same type except for 2705 // top-level cv-qualifiers, and the type to which the reference 2706 // initialized by S2 refers is more cv-qualified than the type 2707 // to which the reference initialized by S1 refers. 2708 QualType T1 = SCS1.getToType(2); 2709 QualType T2 = SCS2.getToType(2); 2710 T1 = S.Context.getCanonicalType(T1); 2711 T2 = S.Context.getCanonicalType(T2); 2712 Qualifiers T1Quals, T2Quals; 2713 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 2714 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 2715 if (UnqualT1 == UnqualT2) { 2716 // If the type is an array type, promote the element qualifiers to the 2717 // type for comparison. 2718 if (isa<ArrayType>(T1) && T1Quals) 2719 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 2720 if (isa<ArrayType>(T2) && T2Quals) 2721 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 2722 if (T2.isMoreQualifiedThan(T1)) 2723 return ImplicitConversionSequence::Better; 2724 else if (T1.isMoreQualifiedThan(T2)) 2725 return ImplicitConversionSequence::Worse; 2726 } 2727 } 2728 2729 return ImplicitConversionSequence::Indistinguishable; 2730} 2731 2732/// CompareQualificationConversions - Compares two standard conversion 2733/// sequences to determine whether they can be ranked based on their 2734/// qualification conversions (C++ 13.3.3.2p3 bullet 3). 2735ImplicitConversionSequence::CompareKind 2736CompareQualificationConversions(Sema &S, 2737 const StandardConversionSequence& SCS1, 2738 const StandardConversionSequence& SCS2) { 2739 // C++ 13.3.3.2p3: 2740 // -- S1 and S2 differ only in their qualification conversion and 2741 // yield similar types T1 and T2 (C++ 4.4), respectively, and the 2742 // cv-qualification signature of type T1 is a proper subset of 2743 // the cv-qualification signature of type T2, and S1 is not the 2744 // deprecated string literal array-to-pointer conversion (4.2). 2745 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second || 2746 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification) 2747 return ImplicitConversionSequence::Indistinguishable; 2748 2749 // FIXME: the example in the standard doesn't use a qualification 2750 // conversion (!) 2751 QualType T1 = SCS1.getToType(2); 2752 QualType T2 = SCS2.getToType(2); 2753 T1 = S.Context.getCanonicalType(T1); 2754 T2 = S.Context.getCanonicalType(T2); 2755 Qualifiers T1Quals, T2Quals; 2756 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 2757 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 2758 2759 // If the types are the same, we won't learn anything by unwrapped 2760 // them. 2761 if (UnqualT1 == UnqualT2) 2762 return ImplicitConversionSequence::Indistinguishable; 2763 2764 // If the type is an array type, promote the element qualifiers to the type 2765 // for comparison. 2766 if (isa<ArrayType>(T1) && T1Quals) 2767 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 2768 if (isa<ArrayType>(T2) && T2Quals) 2769 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 2770 2771 ImplicitConversionSequence::CompareKind Result 2772 = ImplicitConversionSequence::Indistinguishable; 2773 while (S.Context.UnwrapSimilarPointerTypes(T1, T2)) { 2774 // Within each iteration of the loop, we check the qualifiers to 2775 // determine if this still looks like a qualification 2776 // conversion. Then, if all is well, we unwrap one more level of 2777 // pointers or pointers-to-members and do it all again 2778 // until there are no more pointers or pointers-to-members left 2779 // to unwrap. This essentially mimics what 2780 // IsQualificationConversion does, but here we're checking for a 2781 // strict subset of qualifiers. 2782 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 2783 // The qualifiers are the same, so this doesn't tell us anything 2784 // about how the sequences rank. 2785 ; 2786 else if (T2.isMoreQualifiedThan(T1)) { 2787 // T1 has fewer qualifiers, so it could be the better sequence. 2788 if (Result == ImplicitConversionSequence::Worse) 2789 // Neither has qualifiers that are a subset of the other's 2790 // qualifiers. 2791 return ImplicitConversionSequence::Indistinguishable; 2792 2793 Result = ImplicitConversionSequence::Better; 2794 } else if (T1.isMoreQualifiedThan(T2)) { 2795 // T2 has fewer qualifiers, so it could be the better sequence. 2796 if (Result == ImplicitConversionSequence::Better) 2797 // Neither has qualifiers that are a subset of the other's 2798 // qualifiers. 2799 return ImplicitConversionSequence::Indistinguishable; 2800 2801 Result = ImplicitConversionSequence::Worse; 2802 } else { 2803 // Qualifiers are disjoint. 2804 return ImplicitConversionSequence::Indistinguishable; 2805 } 2806 2807 // If the types after this point are equivalent, we're done. 2808 if (S.Context.hasSameUnqualifiedType(T1, T2)) 2809 break; 2810 } 2811 2812 // Check that the winning standard conversion sequence isn't using 2813 // the deprecated string literal array to pointer conversion. 2814 switch (Result) { 2815 case ImplicitConversionSequence::Better: 2816 if (SCS1.DeprecatedStringLiteralToCharPtr) 2817 Result = ImplicitConversionSequence::Indistinguishable; 2818 break; 2819 2820 case ImplicitConversionSequence::Indistinguishable: 2821 break; 2822 2823 case ImplicitConversionSequence::Worse: 2824 if (SCS2.DeprecatedStringLiteralToCharPtr) 2825 Result = ImplicitConversionSequence::Indistinguishable; 2826 break; 2827 } 2828 2829 return Result; 2830} 2831 2832/// CompareDerivedToBaseConversions - Compares two standard conversion 2833/// sequences to determine whether they can be ranked based on their 2834/// various kinds of derived-to-base conversions (C++ 2835/// [over.ics.rank]p4b3). As part of these checks, we also look at 2836/// conversions between Objective-C interface types. 2837ImplicitConversionSequence::CompareKind 2838CompareDerivedToBaseConversions(Sema &S, 2839 const StandardConversionSequence& SCS1, 2840 const StandardConversionSequence& SCS2) { 2841 QualType FromType1 = SCS1.getFromType(); 2842 QualType ToType1 = SCS1.getToType(1); 2843 QualType FromType2 = SCS2.getFromType(); 2844 QualType ToType2 = SCS2.getToType(1); 2845 2846 // Adjust the types we're converting from via the array-to-pointer 2847 // conversion, if we need to. 2848 if (SCS1.First == ICK_Array_To_Pointer) 2849 FromType1 = S.Context.getArrayDecayedType(FromType1); 2850 if (SCS2.First == ICK_Array_To_Pointer) 2851 FromType2 = S.Context.getArrayDecayedType(FromType2); 2852 2853 // Canonicalize all of the types. 2854 FromType1 = S.Context.getCanonicalType(FromType1); 2855 ToType1 = S.Context.getCanonicalType(ToType1); 2856 FromType2 = S.Context.getCanonicalType(FromType2); 2857 ToType2 = S.Context.getCanonicalType(ToType2); 2858 2859 // C++ [over.ics.rank]p4b3: 2860 // 2861 // If class B is derived directly or indirectly from class A and 2862 // class C is derived directly or indirectly from B, 2863 // 2864 // Compare based on pointer conversions. 2865 if (SCS1.Second == ICK_Pointer_Conversion && 2866 SCS2.Second == ICK_Pointer_Conversion && 2867 /*FIXME: Remove if Objective-C id conversions get their own rank*/ 2868 FromType1->isPointerType() && FromType2->isPointerType() && 2869 ToType1->isPointerType() && ToType2->isPointerType()) { 2870 QualType FromPointee1 2871 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 2872 QualType ToPointee1 2873 = ToType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 2874 QualType FromPointee2 2875 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 2876 QualType ToPointee2 2877 = ToType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 2878 2879 // -- conversion of C* to B* is better than conversion of C* to A*, 2880 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 2881 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 2882 return ImplicitConversionSequence::Better; 2883 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 2884 return ImplicitConversionSequence::Worse; 2885 } 2886 2887 // -- conversion of B* to A* is better than conversion of C* to A*, 2888 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) { 2889 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 2890 return ImplicitConversionSequence::Better; 2891 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 2892 return ImplicitConversionSequence::Worse; 2893 } 2894 } else if (SCS1.Second == ICK_Pointer_Conversion && 2895 SCS2.Second == ICK_Pointer_Conversion) { 2896 const ObjCObjectPointerType *FromPtr1 2897 = FromType1->getAs<ObjCObjectPointerType>(); 2898 const ObjCObjectPointerType *FromPtr2 2899 = FromType2->getAs<ObjCObjectPointerType>(); 2900 const ObjCObjectPointerType *ToPtr1 2901 = ToType1->getAs<ObjCObjectPointerType>(); 2902 const ObjCObjectPointerType *ToPtr2 2903 = ToType2->getAs<ObjCObjectPointerType>(); 2904 2905 if (FromPtr1 && FromPtr2 && ToPtr1 && ToPtr2) { 2906 // Apply the same conversion ranking rules for Objective-C pointer types 2907 // that we do for C++ pointers to class types. However, we employ the 2908 // Objective-C pseudo-subtyping relationship used for assignment of 2909 // Objective-C pointer types. 2910 bool FromAssignLeft 2911 = S.Context.canAssignObjCInterfaces(FromPtr1, FromPtr2); 2912 bool FromAssignRight 2913 = S.Context.canAssignObjCInterfaces(FromPtr2, FromPtr1); 2914 bool ToAssignLeft 2915 = S.Context.canAssignObjCInterfaces(ToPtr1, ToPtr2); 2916 bool ToAssignRight 2917 = S.Context.canAssignObjCInterfaces(ToPtr2, ToPtr1); 2918 2919 // A conversion to an a non-id object pointer type or qualified 'id' 2920 // type is better than a conversion to 'id'. 2921 if (ToPtr1->isObjCIdType() && 2922 (ToPtr2->isObjCQualifiedIdType() || ToPtr2->getInterfaceDecl())) 2923 return ImplicitConversionSequence::Worse; 2924 if (ToPtr2->isObjCIdType() && 2925 (ToPtr1->isObjCQualifiedIdType() || ToPtr1->getInterfaceDecl())) 2926 return ImplicitConversionSequence::Better; 2927 2928 // A conversion to a non-id object pointer type is better than a 2929 // conversion to a qualified 'id' type 2930 if (ToPtr1->isObjCQualifiedIdType() && ToPtr2->getInterfaceDecl()) 2931 return ImplicitConversionSequence::Worse; 2932 if (ToPtr2->isObjCQualifiedIdType() && ToPtr1->getInterfaceDecl()) 2933 return ImplicitConversionSequence::Better; 2934 2935 // A conversion to an a non-Class object pointer type or qualified 'Class' 2936 // type is better than a conversion to 'Class'. 2937 if (ToPtr1->isObjCClassType() && 2938 (ToPtr2->isObjCQualifiedClassType() || ToPtr2->getInterfaceDecl())) 2939 return ImplicitConversionSequence::Worse; 2940 if (ToPtr2->isObjCClassType() && 2941 (ToPtr1->isObjCQualifiedClassType() || ToPtr1->getInterfaceDecl())) 2942 return ImplicitConversionSequence::Better; 2943 2944 // A conversion to a non-Class object pointer type is better than a 2945 // conversion to a qualified 'Class' type. 2946 if (ToPtr1->isObjCQualifiedClassType() && ToPtr2->getInterfaceDecl()) 2947 return ImplicitConversionSequence::Worse; 2948 if (ToPtr2->isObjCQualifiedClassType() && ToPtr1->getInterfaceDecl()) 2949 return ImplicitConversionSequence::Better; 2950 2951 // -- "conversion of C* to B* is better than conversion of C* to A*," 2952 if (S.Context.hasSameType(FromType1, FromType2) && 2953 !FromPtr1->isObjCIdType() && !FromPtr1->isObjCClassType() && 2954 (ToAssignLeft != ToAssignRight)) 2955 return ToAssignLeft? ImplicitConversionSequence::Worse 2956 : ImplicitConversionSequence::Better; 2957 2958 // -- "conversion of B* to A* is better than conversion of C* to A*," 2959 if (S.Context.hasSameUnqualifiedType(ToType1, ToType2) && 2960 (FromAssignLeft != FromAssignRight)) 2961 return FromAssignLeft? ImplicitConversionSequence::Better 2962 : ImplicitConversionSequence::Worse; 2963 } 2964 } 2965 2966 // Ranking of member-pointer types. 2967 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member && 2968 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() && 2969 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) { 2970 const MemberPointerType * FromMemPointer1 = 2971 FromType1->getAs<MemberPointerType>(); 2972 const MemberPointerType * ToMemPointer1 = 2973 ToType1->getAs<MemberPointerType>(); 2974 const MemberPointerType * FromMemPointer2 = 2975 FromType2->getAs<MemberPointerType>(); 2976 const MemberPointerType * ToMemPointer2 = 2977 ToType2->getAs<MemberPointerType>(); 2978 const Type *FromPointeeType1 = FromMemPointer1->getClass(); 2979 const Type *ToPointeeType1 = ToMemPointer1->getClass(); 2980 const Type *FromPointeeType2 = FromMemPointer2->getClass(); 2981 const Type *ToPointeeType2 = ToMemPointer2->getClass(); 2982 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType(); 2983 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType(); 2984 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType(); 2985 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType(); 2986 // conversion of A::* to B::* is better than conversion of A::* to C::*, 2987 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 2988 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 2989 return ImplicitConversionSequence::Worse; 2990 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 2991 return ImplicitConversionSequence::Better; 2992 } 2993 // conversion of B::* to C::* is better than conversion of A::* to C::* 2994 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) { 2995 if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 2996 return ImplicitConversionSequence::Better; 2997 else if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 2998 return ImplicitConversionSequence::Worse; 2999 } 3000 } 3001 3002 if (SCS1.Second == ICK_Derived_To_Base) { 3003 // -- conversion of C to B is better than conversion of C to A, 3004 // -- binding of an expression of type C to a reference of type 3005 // B& is better than binding an expression of type C to a 3006 // reference of type A&, 3007 if (S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3008 !S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3009 if (S.IsDerivedFrom(ToType1, ToType2)) 3010 return ImplicitConversionSequence::Better; 3011 else if (S.IsDerivedFrom(ToType2, ToType1)) 3012 return ImplicitConversionSequence::Worse; 3013 } 3014 3015 // -- conversion of B to A is better than conversion of C to A. 3016 // -- binding of an expression of type B to a reference of type 3017 // A& is better than binding an expression of type C to a 3018 // reference of type A&, 3019 if (!S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3020 S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3021 if (S.IsDerivedFrom(FromType2, FromType1)) 3022 return ImplicitConversionSequence::Better; 3023 else if (S.IsDerivedFrom(FromType1, FromType2)) 3024 return ImplicitConversionSequence::Worse; 3025 } 3026 } 3027 3028 return ImplicitConversionSequence::Indistinguishable; 3029} 3030 3031/// CompareReferenceRelationship - Compare the two types T1 and T2 to 3032/// determine whether they are reference-related, 3033/// reference-compatible, reference-compatible with added 3034/// qualification, or incompatible, for use in C++ initialization by 3035/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 3036/// type, and the first type (T1) is the pointee type of the reference 3037/// type being initialized. 3038Sema::ReferenceCompareResult 3039Sema::CompareReferenceRelationship(SourceLocation Loc, 3040 QualType OrigT1, QualType OrigT2, 3041 bool &DerivedToBase, 3042 bool &ObjCConversion) { 3043 assert(!OrigT1->isReferenceType() && 3044 "T1 must be the pointee type of the reference type"); 3045 assert(!OrigT2->isReferenceType() && "T2 cannot be a reference type"); 3046 3047 QualType T1 = Context.getCanonicalType(OrigT1); 3048 QualType T2 = Context.getCanonicalType(OrigT2); 3049 Qualifiers T1Quals, T2Quals; 3050 QualType UnqualT1 = Context.getUnqualifiedArrayType(T1, T1Quals); 3051 QualType UnqualT2 = Context.getUnqualifiedArrayType(T2, T2Quals); 3052 3053 // C++ [dcl.init.ref]p4: 3054 // Given types "cv1 T1" and "cv2 T2," "cv1 T1" is 3055 // reference-related to "cv2 T2" if T1 is the same type as T2, or 3056 // T1 is a base class of T2. 3057 DerivedToBase = false; 3058 ObjCConversion = false; 3059 if (UnqualT1 == UnqualT2) { 3060 // Nothing to do. 3061 } else if (!RequireCompleteType(Loc, OrigT2, PDiag()) && 3062 IsDerivedFrom(UnqualT2, UnqualT1)) 3063 DerivedToBase = true; 3064 else if (UnqualT1->isObjCObjectOrInterfaceType() && 3065 UnqualT2->isObjCObjectOrInterfaceType() && 3066 Context.canBindObjCObjectType(UnqualT1, UnqualT2)) 3067 ObjCConversion = true; 3068 else 3069 return Ref_Incompatible; 3070 3071 // At this point, we know that T1 and T2 are reference-related (at 3072 // least). 3073 3074 // If the type is an array type, promote the element qualifiers to the type 3075 // for comparison. 3076 if (isa<ArrayType>(T1) && T1Quals) 3077 T1 = Context.getQualifiedType(UnqualT1, T1Quals); 3078 if (isa<ArrayType>(T2) && T2Quals) 3079 T2 = Context.getQualifiedType(UnqualT2, T2Quals); 3080 3081 // C++ [dcl.init.ref]p4: 3082 // "cv1 T1" is reference-compatible with "cv2 T2" if T1 is 3083 // reference-related to T2 and cv1 is the same cv-qualification 3084 // as, or greater cv-qualification than, cv2. For purposes of 3085 // overload resolution, cases for which cv1 is greater 3086 // cv-qualification than cv2 are identified as 3087 // reference-compatible with added qualification (see 13.3.3.2). 3088 // 3089 // Note that we also require equivalence of Objective-C GC and address-space 3090 // qualifiers when performing these computations, so that e.g., an int in 3091 // address space 1 is not reference-compatible with an int in address 3092 // space 2. 3093 if (T1Quals == T2Quals) 3094 return Ref_Compatible; 3095 else if (T1.isMoreQualifiedThan(T2)) 3096 return Ref_Compatible_With_Added_Qualification; 3097 else 3098 return Ref_Related; 3099} 3100 3101/// \brief Look for a user-defined conversion to an value reference-compatible 3102/// with DeclType. Return true if something definite is found. 3103static bool 3104FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS, 3105 QualType DeclType, SourceLocation DeclLoc, 3106 Expr *Init, QualType T2, bool AllowRvalues, 3107 bool AllowExplicit) { 3108 assert(T2->isRecordType() && "Can only find conversions of record types."); 3109 CXXRecordDecl *T2RecordDecl 3110 = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl()); 3111 3112 OverloadCandidateSet CandidateSet(DeclLoc); 3113 const UnresolvedSetImpl *Conversions 3114 = T2RecordDecl->getVisibleConversionFunctions(); 3115 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3116 E = Conversions->end(); I != E; ++I) { 3117 NamedDecl *D = *I; 3118 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3119 if (isa<UsingShadowDecl>(D)) 3120 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3121 3122 FunctionTemplateDecl *ConvTemplate 3123 = dyn_cast<FunctionTemplateDecl>(D); 3124 CXXConversionDecl *Conv; 3125 if (ConvTemplate) 3126 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3127 else 3128 Conv = cast<CXXConversionDecl>(D); 3129 3130 // If this is an explicit conversion, and we're not allowed to consider 3131 // explicit conversions, skip it. 3132 if (!AllowExplicit && Conv->isExplicit()) 3133 continue; 3134 3135 if (AllowRvalues) { 3136 bool DerivedToBase = false; 3137 bool ObjCConversion = false; 3138 if (!ConvTemplate && 3139 S.CompareReferenceRelationship( 3140 DeclLoc, 3141 Conv->getConversionType().getNonReferenceType() 3142 .getUnqualifiedType(), 3143 DeclType.getNonReferenceType().getUnqualifiedType(), 3144 DerivedToBase, ObjCConversion) == 3145 Sema::Ref_Incompatible) 3146 continue; 3147 } else { 3148 // If the conversion function doesn't return a reference type, 3149 // it can't be considered for this conversion. An rvalue reference 3150 // is only acceptable if its referencee is a function type. 3151 3152 const ReferenceType *RefType = 3153 Conv->getConversionType()->getAs<ReferenceType>(); 3154 if (!RefType || 3155 (!RefType->isLValueReferenceType() && 3156 !RefType->getPointeeType()->isFunctionType())) 3157 continue; 3158 } 3159 3160 if (ConvTemplate) 3161 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), ActingDC, 3162 Init, DeclType, CandidateSet); 3163 else 3164 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Init, 3165 DeclType, CandidateSet); 3166 } 3167 3168 OverloadCandidateSet::iterator Best; 3169 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 3170 case OR_Success: 3171 // C++ [over.ics.ref]p1: 3172 // 3173 // [...] If the parameter binds directly to the result of 3174 // applying a conversion function to the argument 3175 // expression, the implicit conversion sequence is a 3176 // user-defined conversion sequence (13.3.3.1.2), with the 3177 // second standard conversion sequence either an identity 3178 // conversion or, if the conversion function returns an 3179 // entity of a type that is a derived class of the parameter 3180 // type, a derived-to-base Conversion. 3181 if (!Best->FinalConversion.DirectBinding) 3182 return false; 3183 3184 if (Best->Function) 3185 S.MarkDeclarationReferenced(DeclLoc, Best->Function); 3186 ICS.setUserDefined(); 3187 ICS.UserDefined.Before = Best->Conversions[0].Standard; 3188 ICS.UserDefined.After = Best->FinalConversion; 3189 ICS.UserDefined.ConversionFunction = Best->Function; 3190 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl.getDecl(); 3191 ICS.UserDefined.EllipsisConversion = false; 3192 assert(ICS.UserDefined.After.ReferenceBinding && 3193 ICS.UserDefined.After.DirectBinding && 3194 "Expected a direct reference binding!"); 3195 return true; 3196 3197 case OR_Ambiguous: 3198 ICS.setAmbiguous(); 3199 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 3200 Cand != CandidateSet.end(); ++Cand) 3201 if (Cand->Viable) 3202 ICS.Ambiguous.addConversion(Cand->Function); 3203 return true; 3204 3205 case OR_No_Viable_Function: 3206 case OR_Deleted: 3207 // There was no suitable conversion, or we found a deleted 3208 // conversion; continue with other checks. 3209 return false; 3210 } 3211 3212 return false; 3213} 3214 3215/// \brief Compute an implicit conversion sequence for reference 3216/// initialization. 3217static ImplicitConversionSequence 3218TryReferenceInit(Sema &S, Expr *&Init, QualType DeclType, 3219 SourceLocation DeclLoc, 3220 bool SuppressUserConversions, 3221 bool AllowExplicit) { 3222 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 3223 3224 // Most paths end in a failed conversion. 3225 ImplicitConversionSequence ICS; 3226 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3227 3228 QualType T1 = DeclType->getAs<ReferenceType>()->getPointeeType(); 3229 QualType T2 = Init->getType(); 3230 3231 // If the initializer is the address of an overloaded function, try 3232 // to resolve the overloaded function. If all goes well, T2 is the 3233 // type of the resulting function. 3234 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 3235 DeclAccessPair Found; 3236 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType, 3237 false, Found)) 3238 T2 = Fn->getType(); 3239 } 3240 3241 // Compute some basic properties of the types and the initializer. 3242 bool isRValRef = DeclType->isRValueReferenceType(); 3243 bool DerivedToBase = false; 3244 bool ObjCConversion = false; 3245 Expr::Classification InitCategory = Init->Classify(S.Context); 3246 Sema::ReferenceCompareResult RefRelationship 3247 = S.CompareReferenceRelationship(DeclLoc, T1, T2, DerivedToBase, 3248 ObjCConversion); 3249 3250 3251 // C++0x [dcl.init.ref]p5: 3252 // A reference to type "cv1 T1" is initialized by an expression 3253 // of type "cv2 T2" as follows: 3254 3255 // -- If reference is an lvalue reference and the initializer expression 3256 if (!isRValRef) { 3257 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is 3258 // reference-compatible with "cv2 T2," or 3259 // 3260 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here. 3261 if (InitCategory.isLValue() && 3262 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 3263 // C++ [over.ics.ref]p1: 3264 // When a parameter of reference type binds directly (8.5.3) 3265 // to an argument expression, the implicit conversion sequence 3266 // is the identity conversion, unless the argument expression 3267 // has a type that is a derived class of the parameter type, 3268 // in which case the implicit conversion sequence is a 3269 // derived-to-base Conversion (13.3.3.1). 3270 ICS.setStandard(); 3271 ICS.Standard.First = ICK_Identity; 3272 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3273 : ObjCConversion? ICK_Compatible_Conversion 3274 : ICK_Identity; 3275 ICS.Standard.Third = ICK_Identity; 3276 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3277 ICS.Standard.setToType(0, T2); 3278 ICS.Standard.setToType(1, T1); 3279 ICS.Standard.setToType(2, T1); 3280 ICS.Standard.ReferenceBinding = true; 3281 ICS.Standard.DirectBinding = true; 3282 ICS.Standard.IsLvalueReference = !isRValRef; 3283 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3284 ICS.Standard.BindsToRvalue = false; 3285 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3286 ICS.Standard.CopyConstructor = 0; 3287 3288 // Nothing more to do: the inaccessibility/ambiguity check for 3289 // derived-to-base conversions is suppressed when we're 3290 // computing the implicit conversion sequence (C++ 3291 // [over.best.ics]p2). 3292 return ICS; 3293 } 3294 3295 // -- has a class type (i.e., T2 is a class type), where T1 is 3296 // not reference-related to T2, and can be implicitly 3297 // converted to an lvalue of type "cv3 T3," where "cv1 T1" 3298 // is reference-compatible with "cv3 T3" 92) (this 3299 // conversion is selected by enumerating the applicable 3300 // conversion functions (13.3.1.6) and choosing the best 3301 // one through overload resolution (13.3)), 3302 if (!SuppressUserConversions && T2->isRecordType() && 3303 !S.RequireCompleteType(DeclLoc, T2, 0) && 3304 RefRelationship == Sema::Ref_Incompatible) { 3305 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3306 Init, T2, /*AllowRvalues=*/false, 3307 AllowExplicit)) 3308 return ICS; 3309 } 3310 } 3311 3312 // -- Otherwise, the reference shall be an lvalue reference to a 3313 // non-volatile const type (i.e., cv1 shall be const), or the reference 3314 // shall be an rvalue reference. 3315 // 3316 // We actually handle one oddity of C++ [over.ics.ref] at this 3317 // point, which is that, due to p2 (which short-circuits reference 3318 // binding by only attempting a simple conversion for non-direct 3319 // bindings) and p3's strange wording, we allow a const volatile 3320 // reference to bind to an rvalue. Hence the check for the presence 3321 // of "const" rather than checking for "const" being the only 3322 // qualifier. 3323 // This is also the point where rvalue references and lvalue inits no longer 3324 // go together. 3325 if (!isRValRef && !T1.isConstQualified()) 3326 return ICS; 3327 3328 // -- If the initializer expression 3329 // 3330 // -- is an xvalue, class prvalue, array prvalue or function 3331 // lvalue and "cv1T1" is reference-compatible with "cv2 T2", or 3332 if (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification && 3333 (InitCategory.isXValue() || 3334 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) || 3335 (InitCategory.isLValue() && T2->isFunctionType()))) { 3336 ICS.setStandard(); 3337 ICS.Standard.First = ICK_Identity; 3338 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3339 : ObjCConversion? ICK_Compatible_Conversion 3340 : ICK_Identity; 3341 ICS.Standard.Third = ICK_Identity; 3342 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3343 ICS.Standard.setToType(0, T2); 3344 ICS.Standard.setToType(1, T1); 3345 ICS.Standard.setToType(2, T1); 3346 ICS.Standard.ReferenceBinding = true; 3347 // In C++0x, this is always a direct binding. In C++98/03, it's a direct 3348 // binding unless we're binding to a class prvalue. 3349 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we 3350 // allow the use of rvalue references in C++98/03 for the benefit of 3351 // standard library implementors; therefore, we need the xvalue check here. 3352 ICS.Standard.DirectBinding = 3353 S.getLangOptions().CPlusPlus0x || 3354 (InitCategory.isPRValue() && !T2->isRecordType()); 3355 ICS.Standard.IsLvalueReference = !isRValRef; 3356 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3357 ICS.Standard.BindsToRvalue = InitCategory.isRValue(); 3358 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3359 ICS.Standard.CopyConstructor = 0; 3360 return ICS; 3361 } 3362 3363 // -- has a class type (i.e., T2 is a class type), where T1 is not 3364 // reference-related to T2, and can be implicitly converted to 3365 // an xvalue, class prvalue, or function lvalue of type 3366 // "cv3 T3", where "cv1 T1" is reference-compatible with 3367 // "cv3 T3", 3368 // 3369 // then the reference is bound to the value of the initializer 3370 // expression in the first case and to the result of the conversion 3371 // in the second case (or, in either case, to an appropriate base 3372 // class subobject). 3373 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3374 T2->isRecordType() && !S.RequireCompleteType(DeclLoc, T2, 0) && 3375 FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3376 Init, T2, /*AllowRvalues=*/true, 3377 AllowExplicit)) { 3378 // In the second case, if the reference is an rvalue reference 3379 // and the second standard conversion sequence of the 3380 // user-defined conversion sequence includes an lvalue-to-rvalue 3381 // conversion, the program is ill-formed. 3382 if (ICS.isUserDefined() && isRValRef && 3383 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue) 3384 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3385 3386 return ICS; 3387 } 3388 3389 // -- Otherwise, a temporary of type "cv1 T1" is created and 3390 // initialized from the initializer expression using the 3391 // rules for a non-reference copy initialization (8.5). The 3392 // reference is then bound to the temporary. If T1 is 3393 // reference-related to T2, cv1 must be the same 3394 // cv-qualification as, or greater cv-qualification than, 3395 // cv2; otherwise, the program is ill-formed. 3396 if (RefRelationship == Sema::Ref_Related) { 3397 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 3398 // we would be reference-compatible or reference-compatible with 3399 // added qualification. But that wasn't the case, so the reference 3400 // initialization fails. 3401 return ICS; 3402 } 3403 3404 // If at least one of the types is a class type, the types are not 3405 // related, and we aren't allowed any user conversions, the 3406 // reference binding fails. This case is important for breaking 3407 // recursion, since TryImplicitConversion below will attempt to 3408 // create a temporary through the use of a copy constructor. 3409 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3410 (T1->isRecordType() || T2->isRecordType())) 3411 return ICS; 3412 3413 // If T1 is reference-related to T2 and the reference is an rvalue 3414 // reference, the initializer expression shall not be an lvalue. 3415 if (RefRelationship >= Sema::Ref_Related && 3416 isRValRef && Init->Classify(S.Context).isLValue()) 3417 return ICS; 3418 3419 // C++ [over.ics.ref]p2: 3420 // When a parameter of reference type is not bound directly to 3421 // an argument expression, the conversion sequence is the one 3422 // required to convert the argument expression to the 3423 // underlying type of the reference according to 3424 // 13.3.3.1. Conceptually, this conversion sequence corresponds 3425 // to copy-initializing a temporary of the underlying type with 3426 // the argument expression. Any difference in top-level 3427 // cv-qualification is subsumed by the initialization itself 3428 // and does not constitute a conversion. 3429 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions, 3430 /*AllowExplicit=*/false, 3431 /*InOverloadResolution=*/false, 3432 /*CStyle=*/false); 3433 3434 // Of course, that's still a reference binding. 3435 if (ICS.isStandard()) { 3436 ICS.Standard.ReferenceBinding = true; 3437 ICS.Standard.IsLvalueReference = !isRValRef; 3438 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3439 ICS.Standard.BindsToRvalue = true; 3440 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3441 } else if (ICS.isUserDefined()) { 3442 ICS.UserDefined.After.ReferenceBinding = true; 3443 ICS.Standard.IsLvalueReference = !isRValRef; 3444 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3445 ICS.Standard.BindsToRvalue = true; 3446 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3447 } 3448 3449 return ICS; 3450} 3451 3452/// TryCopyInitialization - Try to copy-initialize a value of type 3453/// ToType from the expression From. Return the implicit conversion 3454/// sequence required to pass this argument, which may be a bad 3455/// conversion sequence (meaning that the argument cannot be passed to 3456/// a parameter of this type). If @p SuppressUserConversions, then we 3457/// do not permit any user-defined conversion sequences. 3458static ImplicitConversionSequence 3459TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 3460 bool SuppressUserConversions, 3461 bool InOverloadResolution) { 3462 if (ToType->isReferenceType()) 3463 return TryReferenceInit(S, From, ToType, 3464 /*FIXME:*/From->getLocStart(), 3465 SuppressUserConversions, 3466 /*AllowExplicit=*/false); 3467 3468 return TryImplicitConversion(S, From, ToType, 3469 SuppressUserConversions, 3470 /*AllowExplicit=*/false, 3471 InOverloadResolution, 3472 /*CStyle=*/false); 3473} 3474 3475/// TryObjectArgumentInitialization - Try to initialize the object 3476/// parameter of the given member function (@c Method) from the 3477/// expression @p From. 3478static ImplicitConversionSequence 3479TryObjectArgumentInitialization(Sema &S, QualType OrigFromType, 3480 Expr::Classification FromClassification, 3481 CXXMethodDecl *Method, 3482 CXXRecordDecl *ActingContext) { 3483 QualType ClassType = S.Context.getTypeDeclType(ActingContext); 3484 // [class.dtor]p2: A destructor can be invoked for a const, volatile or 3485 // const volatile object. 3486 unsigned Quals = isa<CXXDestructorDecl>(Method) ? 3487 Qualifiers::Const | Qualifiers::Volatile : Method->getTypeQualifiers(); 3488 QualType ImplicitParamType = S.Context.getCVRQualifiedType(ClassType, Quals); 3489 3490 // Set up the conversion sequence as a "bad" conversion, to allow us 3491 // to exit early. 3492 ImplicitConversionSequence ICS; 3493 3494 // We need to have an object of class type. 3495 QualType FromType = OrigFromType; 3496 if (const PointerType *PT = FromType->getAs<PointerType>()) { 3497 FromType = PT->getPointeeType(); 3498 3499 // When we had a pointer, it's implicitly dereferenced, so we 3500 // better have an lvalue. 3501 assert(FromClassification.isLValue()); 3502 } 3503 3504 assert(FromType->isRecordType()); 3505 3506 // C++0x [over.match.funcs]p4: 3507 // For non-static member functions, the type of the implicit object 3508 // parameter is 3509 // 3510 // - "lvalue reference to cv X" for functions declared without a 3511 // ref-qualifier or with the & ref-qualifier 3512 // - "rvalue reference to cv X" for functions declared with the && 3513 // ref-qualifier 3514 // 3515 // where X is the class of which the function is a member and cv is the 3516 // cv-qualification on the member function declaration. 3517 // 3518 // However, when finding an implicit conversion sequence for the argument, we 3519 // are not allowed to create temporaries or perform user-defined conversions 3520 // (C++ [over.match.funcs]p5). We perform a simplified version of 3521 // reference binding here, that allows class rvalues to bind to 3522 // non-constant references. 3523 3524 // First check the qualifiers. 3525 QualType FromTypeCanon = S.Context.getCanonicalType(FromType); 3526 if (ImplicitParamType.getCVRQualifiers() 3527 != FromTypeCanon.getLocalCVRQualifiers() && 3528 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) { 3529 ICS.setBad(BadConversionSequence::bad_qualifiers, 3530 OrigFromType, ImplicitParamType); 3531 return ICS; 3532 } 3533 3534 // Check that we have either the same type or a derived type. It 3535 // affects the conversion rank. 3536 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType); 3537 ImplicitConversionKind SecondKind; 3538 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) { 3539 SecondKind = ICK_Identity; 3540 } else if (S.IsDerivedFrom(FromType, ClassType)) 3541 SecondKind = ICK_Derived_To_Base; 3542 else { 3543 ICS.setBad(BadConversionSequence::unrelated_class, 3544 FromType, ImplicitParamType); 3545 return ICS; 3546 } 3547 3548 // Check the ref-qualifier. 3549 switch (Method->getRefQualifier()) { 3550 case RQ_None: 3551 // Do nothing; we don't care about lvalueness or rvalueness. 3552 break; 3553 3554 case RQ_LValue: 3555 if (!FromClassification.isLValue() && Quals != Qualifiers::Const) { 3556 // non-const lvalue reference cannot bind to an rvalue 3557 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType, 3558 ImplicitParamType); 3559 return ICS; 3560 } 3561 break; 3562 3563 case RQ_RValue: 3564 if (!FromClassification.isRValue()) { 3565 // rvalue reference cannot bind to an lvalue 3566 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType, 3567 ImplicitParamType); 3568 return ICS; 3569 } 3570 break; 3571 } 3572 3573 // Success. Mark this as a reference binding. 3574 ICS.setStandard(); 3575 ICS.Standard.setAsIdentityConversion(); 3576 ICS.Standard.Second = SecondKind; 3577 ICS.Standard.setFromType(FromType); 3578 ICS.Standard.setAllToTypes(ImplicitParamType); 3579 ICS.Standard.ReferenceBinding = true; 3580 ICS.Standard.DirectBinding = true; 3581 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue; 3582 ICS.Standard.BindsToFunctionLvalue = false; 3583 ICS.Standard.BindsToRvalue = FromClassification.isRValue(); 3584 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier 3585 = (Method->getRefQualifier() == RQ_None); 3586 return ICS; 3587} 3588 3589/// PerformObjectArgumentInitialization - Perform initialization of 3590/// the implicit object parameter for the given Method with the given 3591/// expression. 3592ExprResult 3593Sema::PerformObjectArgumentInitialization(Expr *From, 3594 NestedNameSpecifier *Qualifier, 3595 NamedDecl *FoundDecl, 3596 CXXMethodDecl *Method) { 3597 QualType FromRecordType, DestType; 3598 QualType ImplicitParamRecordType = 3599 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType(); 3600 3601 Expr::Classification FromClassification; 3602 if (const PointerType *PT = From->getType()->getAs<PointerType>()) { 3603 FromRecordType = PT->getPointeeType(); 3604 DestType = Method->getThisType(Context); 3605 FromClassification = Expr::Classification::makeSimpleLValue(); 3606 } else { 3607 FromRecordType = From->getType(); 3608 DestType = ImplicitParamRecordType; 3609 FromClassification = From->Classify(Context); 3610 } 3611 3612 // Note that we always use the true parent context when performing 3613 // the actual argument initialization. 3614 ImplicitConversionSequence ICS 3615 = TryObjectArgumentInitialization(*this, From->getType(), FromClassification, 3616 Method, Method->getParent()); 3617 if (ICS.isBad()) { 3618 if (ICS.Bad.Kind == BadConversionSequence::bad_qualifiers) { 3619 Qualifiers FromQs = FromRecordType.getQualifiers(); 3620 Qualifiers ToQs = DestType.getQualifiers(); 3621 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 3622 if (CVR) { 3623 Diag(From->getSourceRange().getBegin(), 3624 diag::err_member_function_call_bad_cvr) 3625 << Method->getDeclName() << FromRecordType << (CVR - 1) 3626 << From->getSourceRange(); 3627 Diag(Method->getLocation(), diag::note_previous_decl) 3628 << Method->getDeclName(); 3629 return ExprError(); 3630 } 3631 } 3632 3633 return Diag(From->getSourceRange().getBegin(), 3634 diag::err_implicit_object_parameter_init) 3635 << ImplicitParamRecordType << FromRecordType << From->getSourceRange(); 3636 } 3637 3638 if (ICS.Standard.Second == ICK_Derived_To_Base) { 3639 ExprResult FromRes = 3640 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method); 3641 if (FromRes.isInvalid()) 3642 return ExprError(); 3643 From = FromRes.take(); 3644 } 3645 3646 if (!Context.hasSameType(From->getType(), DestType)) 3647 From = ImpCastExprToType(From, DestType, CK_NoOp, 3648 From->getType()->isPointerType() ? VK_RValue : VK_LValue).take(); 3649 return Owned(From); 3650} 3651 3652/// TryContextuallyConvertToBool - Attempt to contextually convert the 3653/// expression From to bool (C++0x [conv]p3). 3654static ImplicitConversionSequence 3655TryContextuallyConvertToBool(Sema &S, Expr *From) { 3656 // FIXME: This is pretty broken. 3657 return TryImplicitConversion(S, From, S.Context.BoolTy, 3658 // FIXME: Are these flags correct? 3659 /*SuppressUserConversions=*/false, 3660 /*AllowExplicit=*/true, 3661 /*InOverloadResolution=*/false, 3662 /*CStyle=*/false); 3663} 3664 3665/// PerformContextuallyConvertToBool - Perform a contextual conversion 3666/// of the expression From to bool (C++0x [conv]p3). 3667ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) { 3668 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From); 3669 if (!ICS.isBad()) 3670 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting); 3671 3672 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy)) 3673 return Diag(From->getSourceRange().getBegin(), 3674 diag::err_typecheck_bool_condition) 3675 << From->getType() << From->getSourceRange(); 3676 return ExprError(); 3677} 3678 3679/// TryContextuallyConvertToObjCId - Attempt to contextually convert the 3680/// expression From to 'id'. 3681static ImplicitConversionSequence 3682TryContextuallyConvertToObjCId(Sema &S, Expr *From) { 3683 QualType Ty = S.Context.getObjCIdType(); 3684 return TryImplicitConversion(S, From, Ty, 3685 // FIXME: Are these flags correct? 3686 /*SuppressUserConversions=*/false, 3687 /*AllowExplicit=*/true, 3688 /*InOverloadResolution=*/false, 3689 /*CStyle=*/false); 3690} 3691 3692/// PerformContextuallyConvertToObjCId - Perform a contextual conversion 3693/// of the expression From to 'id'. 3694ExprResult Sema::PerformContextuallyConvertToObjCId(Expr *From) { 3695 QualType Ty = Context.getObjCIdType(); 3696 ImplicitConversionSequence ICS = TryContextuallyConvertToObjCId(*this, From); 3697 if (!ICS.isBad()) 3698 return PerformImplicitConversion(From, Ty, ICS, AA_Converting); 3699 return ExprError(); 3700} 3701 3702/// \brief Attempt to convert the given expression to an integral or 3703/// enumeration type. 3704/// 3705/// This routine will attempt to convert an expression of class type to an 3706/// integral or enumeration type, if that class type only has a single 3707/// conversion to an integral or enumeration type. 3708/// 3709/// \param Loc The source location of the construct that requires the 3710/// conversion. 3711/// 3712/// \param FromE The expression we're converting from. 3713/// 3714/// \param NotIntDiag The diagnostic to be emitted if the expression does not 3715/// have integral or enumeration type. 3716/// 3717/// \param IncompleteDiag The diagnostic to be emitted if the expression has 3718/// incomplete class type. 3719/// 3720/// \param ExplicitConvDiag The diagnostic to be emitted if we're calling an 3721/// explicit conversion function (because no implicit conversion functions 3722/// were available). This is a recovery mode. 3723/// 3724/// \param ExplicitConvNote The note to be emitted with \p ExplicitConvDiag, 3725/// showing which conversion was picked. 3726/// 3727/// \param AmbigDiag The diagnostic to be emitted if there is more than one 3728/// conversion function that could convert to integral or enumeration type. 3729/// 3730/// \param AmbigNote The note to be emitted with \p AmbigDiag for each 3731/// usable conversion function. 3732/// 3733/// \param ConvDiag The diagnostic to be emitted if we are calling a conversion 3734/// function, which may be an extension in this case. 3735/// 3736/// \returns The expression, converted to an integral or enumeration type if 3737/// successful. 3738ExprResult 3739Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From, 3740 const PartialDiagnostic &NotIntDiag, 3741 const PartialDiagnostic &IncompleteDiag, 3742 const PartialDiagnostic &ExplicitConvDiag, 3743 const PartialDiagnostic &ExplicitConvNote, 3744 const PartialDiagnostic &AmbigDiag, 3745 const PartialDiagnostic &AmbigNote, 3746 const PartialDiagnostic &ConvDiag) { 3747 // We can't perform any more checking for type-dependent expressions. 3748 if (From->isTypeDependent()) 3749 return Owned(From); 3750 3751 // If the expression already has integral or enumeration type, we're golden. 3752 QualType T = From->getType(); 3753 if (T->isIntegralOrEnumerationType()) 3754 return Owned(From); 3755 3756 // FIXME: Check for missing '()' if T is a function type? 3757 3758 // If we don't have a class type in C++, there's no way we can get an 3759 // expression of integral or enumeration type. 3760 const RecordType *RecordTy = T->getAs<RecordType>(); 3761 if (!RecordTy || !getLangOptions().CPlusPlus) { 3762 Diag(Loc, NotIntDiag) 3763 << T << From->getSourceRange(); 3764 return Owned(From); 3765 } 3766 3767 // We must have a complete class type. 3768 if (RequireCompleteType(Loc, T, IncompleteDiag)) 3769 return Owned(From); 3770 3771 // Look for a conversion to an integral or enumeration type. 3772 UnresolvedSet<4> ViableConversions; 3773 UnresolvedSet<4> ExplicitConversions; 3774 const UnresolvedSetImpl *Conversions 3775 = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions(); 3776 3777 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3778 E = Conversions->end(); 3779 I != E; 3780 ++I) { 3781 if (CXXConversionDecl *Conversion 3782 = dyn_cast<CXXConversionDecl>((*I)->getUnderlyingDecl())) 3783 if (Conversion->getConversionType().getNonReferenceType() 3784 ->isIntegralOrEnumerationType()) { 3785 if (Conversion->isExplicit()) 3786 ExplicitConversions.addDecl(I.getDecl(), I.getAccess()); 3787 else 3788 ViableConversions.addDecl(I.getDecl(), I.getAccess()); 3789 } 3790 } 3791 3792 switch (ViableConversions.size()) { 3793 case 0: 3794 if (ExplicitConversions.size() == 1) { 3795 DeclAccessPair Found = ExplicitConversions[0]; 3796 CXXConversionDecl *Conversion 3797 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 3798 3799 // The user probably meant to invoke the given explicit 3800 // conversion; use it. 3801 QualType ConvTy 3802 = Conversion->getConversionType().getNonReferenceType(); 3803 std::string TypeStr; 3804 ConvTy.getAsStringInternal(TypeStr, Context.PrintingPolicy); 3805 3806 Diag(Loc, ExplicitConvDiag) 3807 << T << ConvTy 3808 << FixItHint::CreateInsertion(From->getLocStart(), 3809 "static_cast<" + TypeStr + ">(") 3810 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(From->getLocEnd()), 3811 ")"); 3812 Diag(Conversion->getLocation(), ExplicitConvNote) 3813 << ConvTy->isEnumeralType() << ConvTy; 3814 3815 // If we aren't in a SFINAE context, build a call to the 3816 // explicit conversion function. 3817 if (isSFINAEContext()) 3818 return ExprError(); 3819 3820 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 3821 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion); 3822 if (Result.isInvalid()) 3823 return ExprError(); 3824 3825 From = Result.get(); 3826 } 3827 3828 // We'll complain below about a non-integral condition type. 3829 break; 3830 3831 case 1: { 3832 // Apply this conversion. 3833 DeclAccessPair Found = ViableConversions[0]; 3834 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 3835 3836 CXXConversionDecl *Conversion 3837 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 3838 QualType ConvTy 3839 = Conversion->getConversionType().getNonReferenceType(); 3840 if (ConvDiag.getDiagID()) { 3841 if (isSFINAEContext()) 3842 return ExprError(); 3843 3844 Diag(Loc, ConvDiag) 3845 << T << ConvTy->isEnumeralType() << ConvTy << From->getSourceRange(); 3846 } 3847 3848 ExprResult Result = BuildCXXMemberCallExpr(From, Found, 3849 cast<CXXConversionDecl>(Found->getUnderlyingDecl())); 3850 if (Result.isInvalid()) 3851 return ExprError(); 3852 3853 From = Result.get(); 3854 break; 3855 } 3856 3857 default: 3858 Diag(Loc, AmbigDiag) 3859 << T << From->getSourceRange(); 3860 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { 3861 CXXConversionDecl *Conv 3862 = cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl()); 3863 QualType ConvTy = Conv->getConversionType().getNonReferenceType(); 3864 Diag(Conv->getLocation(), AmbigNote) 3865 << ConvTy->isEnumeralType() << ConvTy; 3866 } 3867 return Owned(From); 3868 } 3869 3870 if (!From->getType()->isIntegralOrEnumerationType()) 3871 Diag(Loc, NotIntDiag) 3872 << From->getType() << From->getSourceRange(); 3873 3874 return Owned(From); 3875} 3876 3877/// AddOverloadCandidate - Adds the given function to the set of 3878/// candidate functions, using the given function call arguments. If 3879/// @p SuppressUserConversions, then don't allow user-defined 3880/// conversions via constructors or conversion operators. 3881/// 3882/// \para PartialOverloading true if we are performing "partial" overloading 3883/// based on an incomplete set of function arguments. This feature is used by 3884/// code completion. 3885void 3886Sema::AddOverloadCandidate(FunctionDecl *Function, 3887 DeclAccessPair FoundDecl, 3888 Expr **Args, unsigned NumArgs, 3889 OverloadCandidateSet& CandidateSet, 3890 bool SuppressUserConversions, 3891 bool PartialOverloading) { 3892 const FunctionProtoType* Proto 3893 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>()); 3894 assert(Proto && "Functions without a prototype cannot be overloaded"); 3895 assert(!Function->getDescribedFunctionTemplate() && 3896 "Use AddTemplateOverloadCandidate for function templates"); 3897 3898 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 3899 if (!isa<CXXConstructorDecl>(Method)) { 3900 // If we get here, it's because we're calling a member function 3901 // that is named without a member access expression (e.g., 3902 // "this->f") that was either written explicitly or created 3903 // implicitly. This can happen with a qualified call to a member 3904 // function, e.g., X::f(). We use an empty type for the implied 3905 // object argument (C++ [over.call.func]p3), and the acting context 3906 // is irrelevant. 3907 AddMethodCandidate(Method, FoundDecl, Method->getParent(), 3908 QualType(), Expr::Classification::makeSimpleLValue(), 3909 Args, NumArgs, CandidateSet, 3910 SuppressUserConversions); 3911 return; 3912 } 3913 // We treat a constructor like a non-member function, since its object 3914 // argument doesn't participate in overload resolution. 3915 } 3916 3917 if (!CandidateSet.isNewCandidate(Function)) 3918 return; 3919 3920 // Overload resolution is always an unevaluated context. 3921 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 3922 3923 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function)){ 3924 // C++ [class.copy]p3: 3925 // A member function template is never instantiated to perform the copy 3926 // of a class object to an object of its class type. 3927 QualType ClassType = Context.getTypeDeclType(Constructor->getParent()); 3928 if (NumArgs == 1 && 3929 Constructor->isSpecializationCopyingObject() && 3930 (Context.hasSameUnqualifiedType(ClassType, Args[0]->getType()) || 3931 IsDerivedFrom(Args[0]->getType(), ClassType))) 3932 return; 3933 } 3934 3935 // Add this candidate 3936 CandidateSet.push_back(OverloadCandidate()); 3937 OverloadCandidate& Candidate = CandidateSet.back(); 3938 Candidate.FoundDecl = FoundDecl; 3939 Candidate.Function = Function; 3940 Candidate.Viable = true; 3941 Candidate.IsSurrogate = false; 3942 Candidate.IgnoreObjectArgument = false; 3943 Candidate.ExplicitCallArguments = NumArgs; 3944 3945 unsigned NumArgsInProto = Proto->getNumArgs(); 3946 3947 // (C++ 13.3.2p2): A candidate function having fewer than m 3948 // parameters is viable only if it has an ellipsis in its parameter 3949 // list (8.3.5). 3950 if ((NumArgs + (PartialOverloading && NumArgs)) > NumArgsInProto && 3951 !Proto->isVariadic()) { 3952 Candidate.Viable = false; 3953 Candidate.FailureKind = ovl_fail_too_many_arguments; 3954 return; 3955 } 3956 3957 // (C++ 13.3.2p2): A candidate function having more than m parameters 3958 // is viable only if the (m+1)st parameter has a default argument 3959 // (8.3.6). For the purposes of overload resolution, the 3960 // parameter list is truncated on the right, so that there are 3961 // exactly m parameters. 3962 unsigned MinRequiredArgs = Function->getMinRequiredArguments(); 3963 if (NumArgs < MinRequiredArgs && !PartialOverloading) { 3964 // Not enough arguments. 3965 Candidate.Viable = false; 3966 Candidate.FailureKind = ovl_fail_too_few_arguments; 3967 return; 3968 } 3969 3970 // Determine the implicit conversion sequences for each of the 3971 // arguments. 3972 Candidate.Conversions.resize(NumArgs); 3973 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 3974 if (ArgIdx < NumArgsInProto) { 3975 // (C++ 13.3.2p3): for F to be a viable function, there shall 3976 // exist for each argument an implicit conversion sequence 3977 // (13.3.3.1) that converts that argument to the corresponding 3978 // parameter of F. 3979 QualType ParamType = Proto->getArgType(ArgIdx); 3980 Candidate.Conversions[ArgIdx] 3981 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 3982 SuppressUserConversions, 3983 /*InOverloadResolution=*/true); 3984 if (Candidate.Conversions[ArgIdx].isBad()) { 3985 Candidate.Viable = false; 3986 Candidate.FailureKind = ovl_fail_bad_conversion; 3987 break; 3988 } 3989 } else { 3990 // (C++ 13.3.2p2): For the purposes of overload resolution, any 3991 // argument for which there is no corresponding parameter is 3992 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 3993 Candidate.Conversions[ArgIdx].setEllipsis(); 3994 } 3995 } 3996} 3997 3998/// \brief Add all of the function declarations in the given function set to 3999/// the overload canddiate set. 4000void Sema::AddFunctionCandidates(const UnresolvedSetImpl &Fns, 4001 Expr **Args, unsigned NumArgs, 4002 OverloadCandidateSet& CandidateSet, 4003 bool SuppressUserConversions) { 4004 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) { 4005 NamedDecl *D = F.getDecl()->getUnderlyingDecl(); 4006 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 4007 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 4008 AddMethodCandidate(cast<CXXMethodDecl>(FD), F.getPair(), 4009 cast<CXXMethodDecl>(FD)->getParent(), 4010 Args[0]->getType(), Args[0]->Classify(Context), 4011 Args + 1, NumArgs - 1, 4012 CandidateSet, SuppressUserConversions); 4013 else 4014 AddOverloadCandidate(FD, F.getPair(), Args, NumArgs, CandidateSet, 4015 SuppressUserConversions); 4016 } else { 4017 FunctionTemplateDecl *FunTmpl = cast<FunctionTemplateDecl>(D); 4018 if (isa<CXXMethodDecl>(FunTmpl->getTemplatedDecl()) && 4019 !cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())->isStatic()) 4020 AddMethodTemplateCandidate(FunTmpl, F.getPair(), 4021 cast<CXXRecordDecl>(FunTmpl->getDeclContext()), 4022 /*FIXME: explicit args */ 0, 4023 Args[0]->getType(), 4024 Args[0]->Classify(Context), 4025 Args + 1, NumArgs - 1, 4026 CandidateSet, 4027 SuppressUserConversions); 4028 else 4029 AddTemplateOverloadCandidate(FunTmpl, F.getPair(), 4030 /*FIXME: explicit args */ 0, 4031 Args, NumArgs, CandidateSet, 4032 SuppressUserConversions); 4033 } 4034 } 4035} 4036 4037/// AddMethodCandidate - Adds a named decl (which is some kind of 4038/// method) as a method candidate to the given overload set. 4039void Sema::AddMethodCandidate(DeclAccessPair FoundDecl, 4040 QualType ObjectType, 4041 Expr::Classification ObjectClassification, 4042 Expr **Args, unsigned NumArgs, 4043 OverloadCandidateSet& CandidateSet, 4044 bool SuppressUserConversions) { 4045 NamedDecl *Decl = FoundDecl.getDecl(); 4046 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(Decl->getDeclContext()); 4047 4048 if (isa<UsingShadowDecl>(Decl)) 4049 Decl = cast<UsingShadowDecl>(Decl)->getTargetDecl(); 4050 4051 if (FunctionTemplateDecl *TD = dyn_cast<FunctionTemplateDecl>(Decl)) { 4052 assert(isa<CXXMethodDecl>(TD->getTemplatedDecl()) && 4053 "Expected a member function template"); 4054 AddMethodTemplateCandidate(TD, FoundDecl, ActingContext, 4055 /*ExplicitArgs*/ 0, 4056 ObjectType, ObjectClassification, Args, NumArgs, 4057 CandidateSet, 4058 SuppressUserConversions); 4059 } else { 4060 AddMethodCandidate(cast<CXXMethodDecl>(Decl), FoundDecl, ActingContext, 4061 ObjectType, ObjectClassification, Args, NumArgs, 4062 CandidateSet, SuppressUserConversions); 4063 } 4064} 4065 4066/// AddMethodCandidate - Adds the given C++ member function to the set 4067/// of candidate functions, using the given function call arguments 4068/// and the object argument (@c Object). For example, in a call 4069/// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain 4070/// both @c a1 and @c a2. If @p SuppressUserConversions, then don't 4071/// allow user-defined conversions via constructors or conversion 4072/// operators. 4073void 4074Sema::AddMethodCandidate(CXXMethodDecl *Method, DeclAccessPair FoundDecl, 4075 CXXRecordDecl *ActingContext, QualType ObjectType, 4076 Expr::Classification ObjectClassification, 4077 Expr **Args, unsigned NumArgs, 4078 OverloadCandidateSet& CandidateSet, 4079 bool SuppressUserConversions) { 4080 const FunctionProtoType* Proto 4081 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>()); 4082 assert(Proto && "Methods without a prototype cannot be overloaded"); 4083 assert(!isa<CXXConstructorDecl>(Method) && 4084 "Use AddOverloadCandidate for constructors"); 4085 4086 if (!CandidateSet.isNewCandidate(Method)) 4087 return; 4088 4089 // Overload resolution is always an unevaluated context. 4090 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4091 4092 // Add this candidate 4093 CandidateSet.push_back(OverloadCandidate()); 4094 OverloadCandidate& Candidate = CandidateSet.back(); 4095 Candidate.FoundDecl = FoundDecl; 4096 Candidate.Function = Method; 4097 Candidate.IsSurrogate = false; 4098 Candidate.IgnoreObjectArgument = false; 4099 Candidate.ExplicitCallArguments = NumArgs; 4100 4101 unsigned NumArgsInProto = Proto->getNumArgs(); 4102 4103 // (C++ 13.3.2p2): A candidate function having fewer than m 4104 // parameters is viable only if it has an ellipsis in its parameter 4105 // list (8.3.5). 4106 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4107 Candidate.Viable = false; 4108 Candidate.FailureKind = ovl_fail_too_many_arguments; 4109 return; 4110 } 4111 4112 // (C++ 13.3.2p2): A candidate function having more than m parameters 4113 // is viable only if the (m+1)st parameter has a default argument 4114 // (8.3.6). For the purposes of overload resolution, the 4115 // parameter list is truncated on the right, so that there are 4116 // exactly m parameters. 4117 unsigned MinRequiredArgs = Method->getMinRequiredArguments(); 4118 if (NumArgs < MinRequiredArgs) { 4119 // Not enough arguments. 4120 Candidate.Viable = false; 4121 Candidate.FailureKind = ovl_fail_too_few_arguments; 4122 return; 4123 } 4124 4125 Candidate.Viable = true; 4126 Candidate.Conversions.resize(NumArgs + 1); 4127 4128 if (Method->isStatic() || ObjectType.isNull()) 4129 // The implicit object argument is ignored. 4130 Candidate.IgnoreObjectArgument = true; 4131 else { 4132 // Determine the implicit conversion sequence for the object 4133 // parameter. 4134 Candidate.Conversions[0] 4135 = TryObjectArgumentInitialization(*this, ObjectType, ObjectClassification, 4136 Method, ActingContext); 4137 if (Candidate.Conversions[0].isBad()) { 4138 Candidate.Viable = false; 4139 Candidate.FailureKind = ovl_fail_bad_conversion; 4140 return; 4141 } 4142 } 4143 4144 // Determine the implicit conversion sequences for each of the 4145 // arguments. 4146 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4147 if (ArgIdx < NumArgsInProto) { 4148 // (C++ 13.3.2p3): for F to be a viable function, there shall 4149 // exist for each argument an implicit conversion sequence 4150 // (13.3.3.1) that converts that argument to the corresponding 4151 // parameter of F. 4152 QualType ParamType = Proto->getArgType(ArgIdx); 4153 Candidate.Conversions[ArgIdx + 1] 4154 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4155 SuppressUserConversions, 4156 /*InOverloadResolution=*/true); 4157 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4158 Candidate.Viable = false; 4159 Candidate.FailureKind = ovl_fail_bad_conversion; 4160 break; 4161 } 4162 } else { 4163 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4164 // argument for which there is no corresponding parameter is 4165 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4166 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4167 } 4168 } 4169} 4170 4171/// \brief Add a C++ member function template as a candidate to the candidate 4172/// set, using template argument deduction to produce an appropriate member 4173/// function template specialization. 4174void 4175Sema::AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl, 4176 DeclAccessPair FoundDecl, 4177 CXXRecordDecl *ActingContext, 4178 TemplateArgumentListInfo *ExplicitTemplateArgs, 4179 QualType ObjectType, 4180 Expr::Classification ObjectClassification, 4181 Expr **Args, unsigned NumArgs, 4182 OverloadCandidateSet& CandidateSet, 4183 bool SuppressUserConversions) { 4184 if (!CandidateSet.isNewCandidate(MethodTmpl)) 4185 return; 4186 4187 // C++ [over.match.funcs]p7: 4188 // In each case where a candidate is a function template, candidate 4189 // function template specializations are generated using template argument 4190 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4191 // candidate functions in the usual way.113) A given name can refer to one 4192 // or more function templates and also to a set of overloaded non-template 4193 // functions. In such a case, the candidate functions generated from each 4194 // function template are combined with the set of non-template candidate 4195 // functions. 4196 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4197 FunctionDecl *Specialization = 0; 4198 if (TemplateDeductionResult Result 4199 = DeduceTemplateArguments(MethodTmpl, ExplicitTemplateArgs, 4200 Args, NumArgs, Specialization, Info)) { 4201 CandidateSet.push_back(OverloadCandidate()); 4202 OverloadCandidate &Candidate = CandidateSet.back(); 4203 Candidate.FoundDecl = FoundDecl; 4204 Candidate.Function = MethodTmpl->getTemplatedDecl(); 4205 Candidate.Viable = false; 4206 Candidate.FailureKind = ovl_fail_bad_deduction; 4207 Candidate.IsSurrogate = false; 4208 Candidate.IgnoreObjectArgument = false; 4209 Candidate.ExplicitCallArguments = NumArgs; 4210 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4211 Info); 4212 return; 4213 } 4214 4215 // Add the function template specialization produced by template argument 4216 // deduction as a candidate. 4217 assert(Specialization && "Missing member function template specialization?"); 4218 assert(isa<CXXMethodDecl>(Specialization) && 4219 "Specialization is not a member function?"); 4220 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), FoundDecl, 4221 ActingContext, ObjectType, ObjectClassification, 4222 Args, NumArgs, CandidateSet, SuppressUserConversions); 4223} 4224 4225/// \brief Add a C++ function template specialization as a candidate 4226/// in the candidate set, using template argument deduction to produce 4227/// an appropriate function template specialization. 4228void 4229Sema::AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate, 4230 DeclAccessPair FoundDecl, 4231 TemplateArgumentListInfo *ExplicitTemplateArgs, 4232 Expr **Args, unsigned NumArgs, 4233 OverloadCandidateSet& CandidateSet, 4234 bool SuppressUserConversions) { 4235 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4236 return; 4237 4238 // C++ [over.match.funcs]p7: 4239 // In each case where a candidate is a function template, candidate 4240 // function template specializations are generated using template argument 4241 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4242 // candidate functions in the usual way.113) A given name can refer to one 4243 // or more function templates and also to a set of overloaded non-template 4244 // functions. In such a case, the candidate functions generated from each 4245 // function template are combined with the set of non-template candidate 4246 // functions. 4247 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4248 FunctionDecl *Specialization = 0; 4249 if (TemplateDeductionResult Result 4250 = DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, 4251 Args, NumArgs, Specialization, Info)) { 4252 CandidateSet.push_back(OverloadCandidate()); 4253 OverloadCandidate &Candidate = CandidateSet.back(); 4254 Candidate.FoundDecl = FoundDecl; 4255 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4256 Candidate.Viable = false; 4257 Candidate.FailureKind = ovl_fail_bad_deduction; 4258 Candidate.IsSurrogate = false; 4259 Candidate.IgnoreObjectArgument = false; 4260 Candidate.ExplicitCallArguments = NumArgs; 4261 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4262 Info); 4263 return; 4264 } 4265 4266 // Add the function template specialization produced by template argument 4267 // deduction as a candidate. 4268 assert(Specialization && "Missing function template specialization?"); 4269 AddOverloadCandidate(Specialization, FoundDecl, Args, NumArgs, CandidateSet, 4270 SuppressUserConversions); 4271} 4272 4273/// AddConversionCandidate - Add a C++ conversion function as a 4274/// candidate in the candidate set (C++ [over.match.conv], 4275/// C++ [over.match.copy]). From is the expression we're converting from, 4276/// and ToType is the type that we're eventually trying to convert to 4277/// (which may or may not be the same type as the type that the 4278/// conversion function produces). 4279void 4280Sema::AddConversionCandidate(CXXConversionDecl *Conversion, 4281 DeclAccessPair FoundDecl, 4282 CXXRecordDecl *ActingContext, 4283 Expr *From, QualType ToType, 4284 OverloadCandidateSet& CandidateSet) { 4285 assert(!Conversion->getDescribedFunctionTemplate() && 4286 "Conversion function templates use AddTemplateConversionCandidate"); 4287 QualType ConvType = Conversion->getConversionType().getNonReferenceType(); 4288 if (!CandidateSet.isNewCandidate(Conversion)) 4289 return; 4290 4291 // Overload resolution is always an unevaluated context. 4292 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4293 4294 // Add this candidate 4295 CandidateSet.push_back(OverloadCandidate()); 4296 OverloadCandidate& Candidate = CandidateSet.back(); 4297 Candidate.FoundDecl = FoundDecl; 4298 Candidate.Function = Conversion; 4299 Candidate.IsSurrogate = false; 4300 Candidate.IgnoreObjectArgument = false; 4301 Candidate.FinalConversion.setAsIdentityConversion(); 4302 Candidate.FinalConversion.setFromType(ConvType); 4303 Candidate.FinalConversion.setAllToTypes(ToType); 4304 Candidate.Viable = true; 4305 Candidate.Conversions.resize(1); 4306 Candidate.ExplicitCallArguments = 1; 4307 4308 // C++ [over.match.funcs]p4: 4309 // For conversion functions, the function is considered to be a member of 4310 // the class of the implicit implied object argument for the purpose of 4311 // defining the type of the implicit object parameter. 4312 // 4313 // Determine the implicit conversion sequence for the implicit 4314 // object parameter. 4315 QualType ImplicitParamType = From->getType(); 4316 if (const PointerType *FromPtrType = ImplicitParamType->getAs<PointerType>()) 4317 ImplicitParamType = FromPtrType->getPointeeType(); 4318 CXXRecordDecl *ConversionContext 4319 = cast<CXXRecordDecl>(ImplicitParamType->getAs<RecordType>()->getDecl()); 4320 4321 Candidate.Conversions[0] 4322 = TryObjectArgumentInitialization(*this, From->getType(), 4323 From->Classify(Context), 4324 Conversion, ConversionContext); 4325 4326 if (Candidate.Conversions[0].isBad()) { 4327 Candidate.Viable = false; 4328 Candidate.FailureKind = ovl_fail_bad_conversion; 4329 return; 4330 } 4331 4332 // We won't go through a user-define type conversion function to convert a 4333 // derived to base as such conversions are given Conversion Rank. They only 4334 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user] 4335 QualType FromCanon 4336 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 4337 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 4338 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 4339 Candidate.Viable = false; 4340 Candidate.FailureKind = ovl_fail_trivial_conversion; 4341 return; 4342 } 4343 4344 // To determine what the conversion from the result of calling the 4345 // conversion function to the type we're eventually trying to 4346 // convert to (ToType), we need to synthesize a call to the 4347 // conversion function and attempt copy initialization from it. This 4348 // makes sure that we get the right semantics with respect to 4349 // lvalues/rvalues and the type. Fortunately, we can allocate this 4350 // call on the stack and we don't need its arguments to be 4351 // well-formed. 4352 DeclRefExpr ConversionRef(Conversion, Conversion->getType(), 4353 VK_LValue, From->getLocStart()); 4354 ImplicitCastExpr ConversionFn(ImplicitCastExpr::OnStack, 4355 Context.getPointerType(Conversion->getType()), 4356 CK_FunctionToPointerDecay, 4357 &ConversionRef, VK_RValue); 4358 4359 QualType CallResultType 4360 = Conversion->getConversionType().getNonLValueExprType(Context); 4361 if (RequireCompleteType(From->getLocStart(), CallResultType, 0)) { 4362 Candidate.Viable = false; 4363 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4364 return; 4365 } 4366 4367 ExprValueKind VK = Expr::getValueKindForType(Conversion->getConversionType()); 4368 4369 // Note that it is safe to allocate CallExpr on the stack here because 4370 // there are 0 arguments (i.e., nothing is allocated using ASTContext's 4371 // allocator). 4372 CallExpr Call(Context, &ConversionFn, 0, 0, CallResultType, VK, 4373 From->getLocStart()); 4374 ImplicitConversionSequence ICS = 4375 TryCopyInitialization(*this, &Call, ToType, 4376 /*SuppressUserConversions=*/true, 4377 /*InOverloadResolution=*/false); 4378 4379 switch (ICS.getKind()) { 4380 case ImplicitConversionSequence::StandardConversion: 4381 Candidate.FinalConversion = ICS.Standard; 4382 4383 // C++ [over.ics.user]p3: 4384 // If the user-defined conversion is specified by a specialization of a 4385 // conversion function template, the second standard conversion sequence 4386 // shall have exact match rank. 4387 if (Conversion->getPrimaryTemplate() && 4388 GetConversionRank(ICS.Standard.Second) != ICR_Exact_Match) { 4389 Candidate.Viable = false; 4390 Candidate.FailureKind = ovl_fail_final_conversion_not_exact; 4391 } 4392 4393 // C++0x [dcl.init.ref]p5: 4394 // In the second case, if the reference is an rvalue reference and 4395 // the second standard conversion sequence of the user-defined 4396 // conversion sequence includes an lvalue-to-rvalue conversion, the 4397 // program is ill-formed. 4398 if (ToType->isRValueReferenceType() && 4399 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 4400 Candidate.Viable = false; 4401 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4402 } 4403 break; 4404 4405 case ImplicitConversionSequence::BadConversion: 4406 Candidate.Viable = false; 4407 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4408 break; 4409 4410 default: 4411 assert(false && 4412 "Can only end up with a standard conversion sequence or failure"); 4413 } 4414} 4415 4416/// \brief Adds a conversion function template specialization 4417/// candidate to the overload set, using template argument deduction 4418/// to deduce the template arguments of the conversion function 4419/// template from the type that we are converting to (C++ 4420/// [temp.deduct.conv]). 4421void 4422Sema::AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate, 4423 DeclAccessPair FoundDecl, 4424 CXXRecordDecl *ActingDC, 4425 Expr *From, QualType ToType, 4426 OverloadCandidateSet &CandidateSet) { 4427 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) && 4428 "Only conversion function templates permitted here"); 4429 4430 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4431 return; 4432 4433 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4434 CXXConversionDecl *Specialization = 0; 4435 if (TemplateDeductionResult Result 4436 = DeduceTemplateArguments(FunctionTemplate, ToType, 4437 Specialization, Info)) { 4438 CandidateSet.push_back(OverloadCandidate()); 4439 OverloadCandidate &Candidate = CandidateSet.back(); 4440 Candidate.FoundDecl = FoundDecl; 4441 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4442 Candidate.Viable = false; 4443 Candidate.FailureKind = ovl_fail_bad_deduction; 4444 Candidate.IsSurrogate = false; 4445 Candidate.IgnoreObjectArgument = false; 4446 Candidate.ExplicitCallArguments = 1; 4447 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4448 Info); 4449 return; 4450 } 4451 4452 // Add the conversion function template specialization produced by 4453 // template argument deduction as a candidate. 4454 assert(Specialization && "Missing function template specialization?"); 4455 AddConversionCandidate(Specialization, FoundDecl, ActingDC, From, ToType, 4456 CandidateSet); 4457} 4458 4459/// AddSurrogateCandidate - Adds a "surrogate" candidate function that 4460/// converts the given @c Object to a function pointer via the 4461/// conversion function @c Conversion, and then attempts to call it 4462/// with the given arguments (C++ [over.call.object]p2-4). Proto is 4463/// the type of function that we'll eventually be calling. 4464void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion, 4465 DeclAccessPair FoundDecl, 4466 CXXRecordDecl *ActingContext, 4467 const FunctionProtoType *Proto, 4468 Expr *Object, 4469 Expr **Args, unsigned NumArgs, 4470 OverloadCandidateSet& CandidateSet) { 4471 if (!CandidateSet.isNewCandidate(Conversion)) 4472 return; 4473 4474 // Overload resolution is always an unevaluated context. 4475 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4476 4477 CandidateSet.push_back(OverloadCandidate()); 4478 OverloadCandidate& Candidate = CandidateSet.back(); 4479 Candidate.FoundDecl = FoundDecl; 4480 Candidate.Function = 0; 4481 Candidate.Surrogate = Conversion; 4482 Candidate.Viable = true; 4483 Candidate.IsSurrogate = true; 4484 Candidate.IgnoreObjectArgument = false; 4485 Candidate.Conversions.resize(NumArgs + 1); 4486 Candidate.ExplicitCallArguments = NumArgs; 4487 4488 // Determine the implicit conversion sequence for the implicit 4489 // object parameter. 4490 ImplicitConversionSequence ObjectInit 4491 = TryObjectArgumentInitialization(*this, Object->getType(), 4492 Object->Classify(Context), 4493 Conversion, ActingContext); 4494 if (ObjectInit.isBad()) { 4495 Candidate.Viable = false; 4496 Candidate.FailureKind = ovl_fail_bad_conversion; 4497 Candidate.Conversions[0] = ObjectInit; 4498 return; 4499 } 4500 4501 // The first conversion is actually a user-defined conversion whose 4502 // first conversion is ObjectInit's standard conversion (which is 4503 // effectively a reference binding). Record it as such. 4504 Candidate.Conversions[0].setUserDefined(); 4505 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard; 4506 Candidate.Conversions[0].UserDefined.EllipsisConversion = false; 4507 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion; 4508 Candidate.Conversions[0].UserDefined.FoundConversionFunction 4509 = FoundDecl.getDecl(); 4510 Candidate.Conversions[0].UserDefined.After 4511 = Candidate.Conversions[0].UserDefined.Before; 4512 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion(); 4513 4514 // Find the 4515 unsigned NumArgsInProto = Proto->getNumArgs(); 4516 4517 // (C++ 13.3.2p2): A candidate function having fewer than m 4518 // parameters is viable only if it has an ellipsis in its parameter 4519 // list (8.3.5). 4520 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4521 Candidate.Viable = false; 4522 Candidate.FailureKind = ovl_fail_too_many_arguments; 4523 return; 4524 } 4525 4526 // Function types don't have any default arguments, so just check if 4527 // we have enough arguments. 4528 if (NumArgs < NumArgsInProto) { 4529 // Not enough arguments. 4530 Candidate.Viable = false; 4531 Candidate.FailureKind = ovl_fail_too_few_arguments; 4532 return; 4533 } 4534 4535 // Determine the implicit conversion sequences for each of the 4536 // arguments. 4537 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4538 if (ArgIdx < NumArgsInProto) { 4539 // (C++ 13.3.2p3): for F to be a viable function, there shall 4540 // exist for each argument an implicit conversion sequence 4541 // (13.3.3.1) that converts that argument to the corresponding 4542 // parameter of F. 4543 QualType ParamType = Proto->getArgType(ArgIdx); 4544 Candidate.Conversions[ArgIdx + 1] 4545 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4546 /*SuppressUserConversions=*/false, 4547 /*InOverloadResolution=*/false); 4548 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4549 Candidate.Viable = false; 4550 Candidate.FailureKind = ovl_fail_bad_conversion; 4551 break; 4552 } 4553 } else { 4554 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4555 // argument for which there is no corresponding parameter is 4556 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4557 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4558 } 4559 } 4560} 4561 4562/// \brief Add overload candidates for overloaded operators that are 4563/// member functions. 4564/// 4565/// Add the overloaded operator candidates that are member functions 4566/// for the operator Op that was used in an operator expression such 4567/// as "x Op y". , Args/NumArgs provides the operator arguments, and 4568/// CandidateSet will store the added overload candidates. (C++ 4569/// [over.match.oper]). 4570void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op, 4571 SourceLocation OpLoc, 4572 Expr **Args, unsigned NumArgs, 4573 OverloadCandidateSet& CandidateSet, 4574 SourceRange OpRange) { 4575 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 4576 4577 // C++ [over.match.oper]p3: 4578 // For a unary operator @ with an operand of a type whose 4579 // cv-unqualified version is T1, and for a binary operator @ with 4580 // a left operand of a type whose cv-unqualified version is T1 and 4581 // a right operand of a type whose cv-unqualified version is T2, 4582 // three sets of candidate functions, designated member 4583 // candidates, non-member candidates and built-in candidates, are 4584 // constructed as follows: 4585 QualType T1 = Args[0]->getType(); 4586 4587 // -- If T1 is a class type, the set of member candidates is the 4588 // result of the qualified lookup of T1::operator@ 4589 // (13.3.1.1.1); otherwise, the set of member candidates is 4590 // empty. 4591 if (const RecordType *T1Rec = T1->getAs<RecordType>()) { 4592 // Complete the type if it can be completed. Otherwise, we're done. 4593 if (RequireCompleteType(OpLoc, T1, PDiag())) 4594 return; 4595 4596 LookupResult Operators(*this, OpName, OpLoc, LookupOrdinaryName); 4597 LookupQualifiedName(Operators, T1Rec->getDecl()); 4598 Operators.suppressDiagnostics(); 4599 4600 for (LookupResult::iterator Oper = Operators.begin(), 4601 OperEnd = Operators.end(); 4602 Oper != OperEnd; 4603 ++Oper) 4604 AddMethodCandidate(Oper.getPair(), Args[0]->getType(), 4605 Args[0]->Classify(Context), Args + 1, NumArgs - 1, 4606 CandidateSet, 4607 /* SuppressUserConversions = */ false); 4608 } 4609} 4610 4611/// AddBuiltinCandidate - Add a candidate for a built-in 4612/// operator. ResultTy and ParamTys are the result and parameter types 4613/// of the built-in candidate, respectively. Args and NumArgs are the 4614/// arguments being passed to the candidate. IsAssignmentOperator 4615/// should be true when this built-in candidate is an assignment 4616/// operator. NumContextualBoolArguments is the number of arguments 4617/// (at the beginning of the argument list) that will be contextually 4618/// converted to bool. 4619void Sema::AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys, 4620 Expr **Args, unsigned NumArgs, 4621 OverloadCandidateSet& CandidateSet, 4622 bool IsAssignmentOperator, 4623 unsigned NumContextualBoolArguments) { 4624 // Overload resolution is always an unevaluated context. 4625 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4626 4627 // Add this candidate 4628 CandidateSet.push_back(OverloadCandidate()); 4629 OverloadCandidate& Candidate = CandidateSet.back(); 4630 Candidate.FoundDecl = DeclAccessPair::make(0, AS_none); 4631 Candidate.Function = 0; 4632 Candidate.IsSurrogate = false; 4633 Candidate.IgnoreObjectArgument = false; 4634 Candidate.BuiltinTypes.ResultTy = ResultTy; 4635 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 4636 Candidate.BuiltinTypes.ParamTypes[ArgIdx] = ParamTys[ArgIdx]; 4637 4638 // Determine the implicit conversion sequences for each of the 4639 // arguments. 4640 Candidate.Viable = true; 4641 Candidate.Conversions.resize(NumArgs); 4642 Candidate.ExplicitCallArguments = NumArgs; 4643 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4644 // C++ [over.match.oper]p4: 4645 // For the built-in assignment operators, conversions of the 4646 // left operand are restricted as follows: 4647 // -- no temporaries are introduced to hold the left operand, and 4648 // -- no user-defined conversions are applied to the left 4649 // operand to achieve a type match with the left-most 4650 // parameter of a built-in candidate. 4651 // 4652 // We block these conversions by turning off user-defined 4653 // conversions, since that is the only way that initialization of 4654 // a reference to a non-class type can occur from something that 4655 // is not of the same type. 4656 if (ArgIdx < NumContextualBoolArguments) { 4657 assert(ParamTys[ArgIdx] == Context.BoolTy && 4658 "Contextual conversion to bool requires bool type"); 4659 Candidate.Conversions[ArgIdx] 4660 = TryContextuallyConvertToBool(*this, Args[ArgIdx]); 4661 } else { 4662 Candidate.Conversions[ArgIdx] 4663 = TryCopyInitialization(*this, Args[ArgIdx], ParamTys[ArgIdx], 4664 ArgIdx == 0 && IsAssignmentOperator, 4665 /*InOverloadResolution=*/false); 4666 } 4667 if (Candidate.Conversions[ArgIdx].isBad()) { 4668 Candidate.Viable = false; 4669 Candidate.FailureKind = ovl_fail_bad_conversion; 4670 break; 4671 } 4672 } 4673} 4674 4675/// BuiltinCandidateTypeSet - A set of types that will be used for the 4676/// candidate operator functions for built-in operators (C++ 4677/// [over.built]). The types are separated into pointer types and 4678/// enumeration types. 4679class BuiltinCandidateTypeSet { 4680 /// TypeSet - A set of types. 4681 typedef llvm::SmallPtrSet<QualType, 8> TypeSet; 4682 4683 /// PointerTypes - The set of pointer types that will be used in the 4684 /// built-in candidates. 4685 TypeSet PointerTypes; 4686 4687 /// MemberPointerTypes - The set of member pointer types that will be 4688 /// used in the built-in candidates. 4689 TypeSet MemberPointerTypes; 4690 4691 /// EnumerationTypes - The set of enumeration types that will be 4692 /// used in the built-in candidates. 4693 TypeSet EnumerationTypes; 4694 4695 /// \brief The set of vector types that will be used in the built-in 4696 /// candidates. 4697 TypeSet VectorTypes; 4698 4699 /// \brief A flag indicating non-record types are viable candidates 4700 bool HasNonRecordTypes; 4701 4702 /// \brief A flag indicating whether either arithmetic or enumeration types 4703 /// were present in the candidate set. 4704 bool HasArithmeticOrEnumeralTypes; 4705 4706 /// \brief A flag indicating whether the nullptr type was present in the 4707 /// candidate set. 4708 bool HasNullPtrType; 4709 4710 /// Sema - The semantic analysis instance where we are building the 4711 /// candidate type set. 4712 Sema &SemaRef; 4713 4714 /// Context - The AST context in which we will build the type sets. 4715 ASTContext &Context; 4716 4717 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4718 const Qualifiers &VisibleQuals); 4719 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty); 4720 4721public: 4722 /// iterator - Iterates through the types that are part of the set. 4723 typedef TypeSet::iterator iterator; 4724 4725 BuiltinCandidateTypeSet(Sema &SemaRef) 4726 : HasNonRecordTypes(false), 4727 HasArithmeticOrEnumeralTypes(false), 4728 HasNullPtrType(false), 4729 SemaRef(SemaRef), 4730 Context(SemaRef.Context) { } 4731 4732 void AddTypesConvertedFrom(QualType Ty, 4733 SourceLocation Loc, 4734 bool AllowUserConversions, 4735 bool AllowExplicitConversions, 4736 const Qualifiers &VisibleTypeConversionsQuals); 4737 4738 /// pointer_begin - First pointer type found; 4739 iterator pointer_begin() { return PointerTypes.begin(); } 4740 4741 /// pointer_end - Past the last pointer type found; 4742 iterator pointer_end() { return PointerTypes.end(); } 4743 4744 /// member_pointer_begin - First member pointer type found; 4745 iterator member_pointer_begin() { return MemberPointerTypes.begin(); } 4746 4747 /// member_pointer_end - Past the last member pointer type found; 4748 iterator member_pointer_end() { return MemberPointerTypes.end(); } 4749 4750 /// enumeration_begin - First enumeration type found; 4751 iterator enumeration_begin() { return EnumerationTypes.begin(); } 4752 4753 /// enumeration_end - Past the last enumeration type found; 4754 iterator enumeration_end() { return EnumerationTypes.end(); } 4755 4756 iterator vector_begin() { return VectorTypes.begin(); } 4757 iterator vector_end() { return VectorTypes.end(); } 4758 4759 bool hasNonRecordTypes() { return HasNonRecordTypes; } 4760 bool hasArithmeticOrEnumeralTypes() { return HasArithmeticOrEnumeralTypes; } 4761 bool hasNullPtrType() const { return HasNullPtrType; } 4762}; 4763 4764/// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to 4765/// the set of pointer types along with any more-qualified variants of 4766/// that type. For example, if @p Ty is "int const *", this routine 4767/// will add "int const *", "int const volatile *", "int const 4768/// restrict *", and "int const volatile restrict *" to the set of 4769/// pointer types. Returns true if the add of @p Ty itself succeeded, 4770/// false otherwise. 4771/// 4772/// FIXME: what to do about extended qualifiers? 4773bool 4774BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4775 const Qualifiers &VisibleQuals) { 4776 4777 // Insert this type. 4778 if (!PointerTypes.insert(Ty)) 4779 return false; 4780 4781 QualType PointeeTy; 4782 const PointerType *PointerTy = Ty->getAs<PointerType>(); 4783 bool buildObjCPtr = false; 4784 if (!PointerTy) { 4785 if (const ObjCObjectPointerType *PTy = Ty->getAs<ObjCObjectPointerType>()) { 4786 PointeeTy = PTy->getPointeeType(); 4787 buildObjCPtr = true; 4788 } 4789 else 4790 assert(false && "type was not a pointer type!"); 4791 } 4792 else 4793 PointeeTy = PointerTy->getPointeeType(); 4794 4795 // Don't add qualified variants of arrays. For one, they're not allowed 4796 // (the qualifier would sink to the element type), and for another, the 4797 // only overload situation where it matters is subscript or pointer +- int, 4798 // and those shouldn't have qualifier variants anyway. 4799 if (PointeeTy->isArrayType()) 4800 return true; 4801 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 4802 if (const ConstantArrayType *Array =Context.getAsConstantArrayType(PointeeTy)) 4803 BaseCVR = Array->getElementType().getCVRQualifiers(); 4804 bool hasVolatile = VisibleQuals.hasVolatile(); 4805 bool hasRestrict = VisibleQuals.hasRestrict(); 4806 4807 // Iterate through all strict supersets of BaseCVR. 4808 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 4809 if ((CVR | BaseCVR) != CVR) continue; 4810 // Skip over Volatile/Restrict if no Volatile/Restrict found anywhere 4811 // in the types. 4812 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue; 4813 if ((CVR & Qualifiers::Restrict) && !hasRestrict) continue; 4814 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 4815 if (!buildObjCPtr) 4816 PointerTypes.insert(Context.getPointerType(QPointeeTy)); 4817 else 4818 PointerTypes.insert(Context.getObjCObjectPointerType(QPointeeTy)); 4819 } 4820 4821 return true; 4822} 4823 4824/// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty 4825/// to the set of pointer types along with any more-qualified variants of 4826/// that type. For example, if @p Ty is "int const *", this routine 4827/// will add "int const *", "int const volatile *", "int const 4828/// restrict *", and "int const volatile restrict *" to the set of 4829/// pointer types. Returns true if the add of @p Ty itself succeeded, 4830/// false otherwise. 4831/// 4832/// FIXME: what to do about extended qualifiers? 4833bool 4834BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants( 4835 QualType Ty) { 4836 // Insert this type. 4837 if (!MemberPointerTypes.insert(Ty)) 4838 return false; 4839 4840 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>(); 4841 assert(PointerTy && "type was not a member pointer type!"); 4842 4843 QualType PointeeTy = PointerTy->getPointeeType(); 4844 // Don't add qualified variants of arrays. For one, they're not allowed 4845 // (the qualifier would sink to the element type), and for another, the 4846 // only overload situation where it matters is subscript or pointer +- int, 4847 // and those shouldn't have qualifier variants anyway. 4848 if (PointeeTy->isArrayType()) 4849 return true; 4850 const Type *ClassTy = PointerTy->getClass(); 4851 4852 // Iterate through all strict supersets of the pointee type's CVR 4853 // qualifiers. 4854 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 4855 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 4856 if ((CVR | BaseCVR) != CVR) continue; 4857 4858 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 4859 MemberPointerTypes.insert( 4860 Context.getMemberPointerType(QPointeeTy, ClassTy)); 4861 } 4862 4863 return true; 4864} 4865 4866/// AddTypesConvertedFrom - Add each of the types to which the type @p 4867/// Ty can be implicit converted to the given set of @p Types. We're 4868/// primarily interested in pointer types and enumeration types. We also 4869/// take member pointer types, for the conditional operator. 4870/// AllowUserConversions is true if we should look at the conversion 4871/// functions of a class type, and AllowExplicitConversions if we 4872/// should also include the explicit conversion functions of a class 4873/// type. 4874void 4875BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty, 4876 SourceLocation Loc, 4877 bool AllowUserConversions, 4878 bool AllowExplicitConversions, 4879 const Qualifiers &VisibleQuals) { 4880 // Only deal with canonical types. 4881 Ty = Context.getCanonicalType(Ty); 4882 4883 // Look through reference types; they aren't part of the type of an 4884 // expression for the purposes of conversions. 4885 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>()) 4886 Ty = RefTy->getPointeeType(); 4887 4888 // If we're dealing with an array type, decay to the pointer. 4889 if (Ty->isArrayType()) 4890 Ty = SemaRef.Context.getArrayDecayedType(Ty); 4891 4892 // Otherwise, we don't care about qualifiers on the type. 4893 Ty = Ty.getLocalUnqualifiedType(); 4894 4895 // Flag if we ever add a non-record type. 4896 const RecordType *TyRec = Ty->getAs<RecordType>(); 4897 HasNonRecordTypes = HasNonRecordTypes || !TyRec; 4898 4899 // Flag if we encounter an arithmetic type. 4900 HasArithmeticOrEnumeralTypes = 4901 HasArithmeticOrEnumeralTypes || Ty->isArithmeticType(); 4902 4903 if (Ty->isObjCIdType() || Ty->isObjCClassType()) 4904 PointerTypes.insert(Ty); 4905 else if (Ty->getAs<PointerType>() || Ty->getAs<ObjCObjectPointerType>()) { 4906 // Insert our type, and its more-qualified variants, into the set 4907 // of types. 4908 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals)) 4909 return; 4910 } else if (Ty->isMemberPointerType()) { 4911 // Member pointers are far easier, since the pointee can't be converted. 4912 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty)) 4913 return; 4914 } else if (Ty->isEnumeralType()) { 4915 HasArithmeticOrEnumeralTypes = true; 4916 EnumerationTypes.insert(Ty); 4917 } else if (Ty->isVectorType()) { 4918 // We treat vector types as arithmetic types in many contexts as an 4919 // extension. 4920 HasArithmeticOrEnumeralTypes = true; 4921 VectorTypes.insert(Ty); 4922 } else if (Ty->isNullPtrType()) { 4923 HasNullPtrType = true; 4924 } else if (AllowUserConversions && TyRec) { 4925 // No conversion functions in incomplete types. 4926 if (SemaRef.RequireCompleteType(Loc, Ty, 0)) 4927 return; 4928 4929 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 4930 const UnresolvedSetImpl *Conversions 4931 = ClassDecl->getVisibleConversionFunctions(); 4932 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 4933 E = Conversions->end(); I != E; ++I) { 4934 NamedDecl *D = I.getDecl(); 4935 if (isa<UsingShadowDecl>(D)) 4936 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 4937 4938 // Skip conversion function templates; they don't tell us anything 4939 // about which builtin types we can convert to. 4940 if (isa<FunctionTemplateDecl>(D)) 4941 continue; 4942 4943 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 4944 if (AllowExplicitConversions || !Conv->isExplicit()) { 4945 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false, 4946 VisibleQuals); 4947 } 4948 } 4949 } 4950} 4951 4952/// \brief Helper function for AddBuiltinOperatorCandidates() that adds 4953/// the volatile- and non-volatile-qualified assignment operators for the 4954/// given type to the candidate set. 4955static void AddBuiltinAssignmentOperatorCandidates(Sema &S, 4956 QualType T, 4957 Expr **Args, 4958 unsigned NumArgs, 4959 OverloadCandidateSet &CandidateSet) { 4960 QualType ParamTypes[2]; 4961 4962 // T& operator=(T&, T) 4963 ParamTypes[0] = S.Context.getLValueReferenceType(T); 4964 ParamTypes[1] = T; 4965 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 4966 /*IsAssignmentOperator=*/true); 4967 4968 if (!S.Context.getCanonicalType(T).isVolatileQualified()) { 4969 // volatile T& operator=(volatile T&, T) 4970 ParamTypes[0] 4971 = S.Context.getLValueReferenceType(S.Context.getVolatileType(T)); 4972 ParamTypes[1] = T; 4973 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 4974 /*IsAssignmentOperator=*/true); 4975 } 4976} 4977 4978/// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers, 4979/// if any, found in visible type conversion functions found in ArgExpr's type. 4980static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) { 4981 Qualifiers VRQuals; 4982 const RecordType *TyRec; 4983 if (const MemberPointerType *RHSMPType = 4984 ArgExpr->getType()->getAs<MemberPointerType>()) 4985 TyRec = RHSMPType->getClass()->getAs<RecordType>(); 4986 else 4987 TyRec = ArgExpr->getType()->getAs<RecordType>(); 4988 if (!TyRec) { 4989 // Just to be safe, assume the worst case. 4990 VRQuals.addVolatile(); 4991 VRQuals.addRestrict(); 4992 return VRQuals; 4993 } 4994 4995 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 4996 if (!ClassDecl->hasDefinition()) 4997 return VRQuals; 4998 4999 const UnresolvedSetImpl *Conversions = 5000 ClassDecl->getVisibleConversionFunctions(); 5001 5002 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 5003 E = Conversions->end(); I != E; ++I) { 5004 NamedDecl *D = I.getDecl(); 5005 if (isa<UsingShadowDecl>(D)) 5006 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 5007 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) { 5008 QualType CanTy = Context.getCanonicalType(Conv->getConversionType()); 5009 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>()) 5010 CanTy = ResTypeRef->getPointeeType(); 5011 // Need to go down the pointer/mempointer chain and add qualifiers 5012 // as see them. 5013 bool done = false; 5014 while (!done) { 5015 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>()) 5016 CanTy = ResTypePtr->getPointeeType(); 5017 else if (const MemberPointerType *ResTypeMPtr = 5018 CanTy->getAs<MemberPointerType>()) 5019 CanTy = ResTypeMPtr->getPointeeType(); 5020 else 5021 done = true; 5022 if (CanTy.isVolatileQualified()) 5023 VRQuals.addVolatile(); 5024 if (CanTy.isRestrictQualified()) 5025 VRQuals.addRestrict(); 5026 if (VRQuals.hasRestrict() && VRQuals.hasVolatile()) 5027 return VRQuals; 5028 } 5029 } 5030 } 5031 return VRQuals; 5032} 5033 5034namespace { 5035 5036/// \brief Helper class to manage the addition of builtin operator overload 5037/// candidates. It provides shared state and utility methods used throughout 5038/// the process, as well as a helper method to add each group of builtin 5039/// operator overloads from the standard to a candidate set. 5040class BuiltinOperatorOverloadBuilder { 5041 // Common instance state available to all overload candidate addition methods. 5042 Sema &S; 5043 Expr **Args; 5044 unsigned NumArgs; 5045 Qualifiers VisibleTypeConversionsQuals; 5046 bool HasArithmeticOrEnumeralCandidateType; 5047 llvm::SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes; 5048 OverloadCandidateSet &CandidateSet; 5049 5050 // Define some constants used to index and iterate over the arithemetic types 5051 // provided via the getArithmeticType() method below. 5052 // The "promoted arithmetic types" are the arithmetic 5053 // types are that preserved by promotion (C++ [over.built]p2). 5054 static const unsigned FirstIntegralType = 3; 5055 static const unsigned LastIntegralType = 18; 5056 static const unsigned FirstPromotedIntegralType = 3, 5057 LastPromotedIntegralType = 9; 5058 static const unsigned FirstPromotedArithmeticType = 0, 5059 LastPromotedArithmeticType = 9; 5060 static const unsigned NumArithmeticTypes = 18; 5061 5062 /// \brief Get the canonical type for a given arithmetic type index. 5063 CanQualType getArithmeticType(unsigned index) { 5064 assert(index < NumArithmeticTypes); 5065 static CanQualType ASTContext::* const 5066 ArithmeticTypes[NumArithmeticTypes] = { 5067 // Start of promoted types. 5068 &ASTContext::FloatTy, 5069 &ASTContext::DoubleTy, 5070 &ASTContext::LongDoubleTy, 5071 5072 // Start of integral types. 5073 &ASTContext::IntTy, 5074 &ASTContext::LongTy, 5075 &ASTContext::LongLongTy, 5076 &ASTContext::UnsignedIntTy, 5077 &ASTContext::UnsignedLongTy, 5078 &ASTContext::UnsignedLongLongTy, 5079 // End of promoted types. 5080 5081 &ASTContext::BoolTy, 5082 &ASTContext::CharTy, 5083 &ASTContext::WCharTy, 5084 &ASTContext::Char16Ty, 5085 &ASTContext::Char32Ty, 5086 &ASTContext::SignedCharTy, 5087 &ASTContext::ShortTy, 5088 &ASTContext::UnsignedCharTy, 5089 &ASTContext::UnsignedShortTy, 5090 // End of integral types. 5091 // FIXME: What about complex? 5092 }; 5093 return S.Context.*ArithmeticTypes[index]; 5094 } 5095 5096 /// \brief Gets the canonical type resulting from the usual arithemetic 5097 /// converions for the given arithmetic types. 5098 CanQualType getUsualArithmeticConversions(unsigned L, unsigned R) { 5099 // Accelerator table for performing the usual arithmetic conversions. 5100 // The rules are basically: 5101 // - if either is floating-point, use the wider floating-point 5102 // - if same signedness, use the higher rank 5103 // - if same size, use unsigned of the higher rank 5104 // - use the larger type 5105 // These rules, together with the axiom that higher ranks are 5106 // never smaller, are sufficient to precompute all of these results 5107 // *except* when dealing with signed types of higher rank. 5108 // (we could precompute SLL x UI for all known platforms, but it's 5109 // better not to make any assumptions). 5110 enum PromotedType { 5111 Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL, Dep=-1 5112 }; 5113 static PromotedType ConversionsTable[LastPromotedArithmeticType] 5114 [LastPromotedArithmeticType] = { 5115 /* Flt*/ { Flt, Dbl, LDbl, Flt, Flt, Flt, Flt, Flt, Flt }, 5116 /* Dbl*/ { Dbl, Dbl, LDbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl }, 5117 /*LDbl*/ { LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl }, 5118 /* SI*/ { Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL }, 5119 /* SL*/ { Flt, Dbl, LDbl, SL, SL, SLL, Dep, UL, ULL }, 5120 /* SLL*/ { Flt, Dbl, LDbl, SLL, SLL, SLL, Dep, Dep, ULL }, 5121 /* UI*/ { Flt, Dbl, LDbl, UI, Dep, Dep, UI, UL, ULL }, 5122 /* UL*/ { Flt, Dbl, LDbl, UL, UL, Dep, UL, UL, ULL }, 5123 /* ULL*/ { Flt, Dbl, LDbl, ULL, ULL, ULL, ULL, ULL, ULL }, 5124 }; 5125 5126 assert(L < LastPromotedArithmeticType); 5127 assert(R < LastPromotedArithmeticType); 5128 int Idx = ConversionsTable[L][R]; 5129 5130 // Fast path: the table gives us a concrete answer. 5131 if (Idx != Dep) return getArithmeticType(Idx); 5132 5133 // Slow path: we need to compare widths. 5134 // An invariant is that the signed type has higher rank. 5135 CanQualType LT = getArithmeticType(L), 5136 RT = getArithmeticType(R); 5137 unsigned LW = S.Context.getIntWidth(LT), 5138 RW = S.Context.getIntWidth(RT); 5139 5140 // If they're different widths, use the signed type. 5141 if (LW > RW) return LT; 5142 else if (LW < RW) return RT; 5143 5144 // Otherwise, use the unsigned type of the signed type's rank. 5145 if (L == SL || R == SL) return S.Context.UnsignedLongTy; 5146 assert(L == SLL || R == SLL); 5147 return S.Context.UnsignedLongLongTy; 5148 } 5149 5150 /// \brief Helper method to factor out the common pattern of adding overloads 5151 /// for '++' and '--' builtin operators. 5152 void addPlusPlusMinusMinusStyleOverloads(QualType CandidateTy, 5153 bool HasVolatile) { 5154 QualType ParamTypes[2] = { 5155 S.Context.getLValueReferenceType(CandidateTy), 5156 S.Context.IntTy 5157 }; 5158 5159 // Non-volatile version. 5160 if (NumArgs == 1) 5161 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5162 else 5163 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5164 5165 // Use a heuristic to reduce number of builtin candidates in the set: 5166 // add volatile version only if there are conversions to a volatile type. 5167 if (HasVolatile) { 5168 ParamTypes[0] = 5169 S.Context.getLValueReferenceType( 5170 S.Context.getVolatileType(CandidateTy)); 5171 if (NumArgs == 1) 5172 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5173 else 5174 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5175 } 5176 } 5177 5178public: 5179 BuiltinOperatorOverloadBuilder( 5180 Sema &S, Expr **Args, unsigned NumArgs, 5181 Qualifiers VisibleTypeConversionsQuals, 5182 bool HasArithmeticOrEnumeralCandidateType, 5183 llvm::SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes, 5184 OverloadCandidateSet &CandidateSet) 5185 : S(S), Args(Args), NumArgs(NumArgs), 5186 VisibleTypeConversionsQuals(VisibleTypeConversionsQuals), 5187 HasArithmeticOrEnumeralCandidateType( 5188 HasArithmeticOrEnumeralCandidateType), 5189 CandidateTypes(CandidateTypes), 5190 CandidateSet(CandidateSet) { 5191 // Validate some of our static helper constants in debug builds. 5192 assert(getArithmeticType(FirstPromotedIntegralType) == S.Context.IntTy && 5193 "Invalid first promoted integral type"); 5194 assert(getArithmeticType(LastPromotedIntegralType - 1) 5195 == S.Context.UnsignedLongLongTy && 5196 "Invalid last promoted integral type"); 5197 assert(getArithmeticType(FirstPromotedArithmeticType) 5198 == S.Context.FloatTy && 5199 "Invalid first promoted arithmetic type"); 5200 assert(getArithmeticType(LastPromotedArithmeticType - 1) 5201 == S.Context.UnsignedLongLongTy && 5202 "Invalid last promoted arithmetic type"); 5203 } 5204 5205 // C++ [over.built]p3: 5206 // 5207 // For every pair (T, VQ), where T is an arithmetic type, and VQ 5208 // is either volatile or empty, there exist candidate operator 5209 // functions of the form 5210 // 5211 // VQ T& operator++(VQ T&); 5212 // T operator++(VQ T&, int); 5213 // 5214 // C++ [over.built]p4: 5215 // 5216 // For every pair (T, VQ), where T is an arithmetic type other 5217 // than bool, and VQ is either volatile or empty, there exist 5218 // candidate operator functions of the form 5219 // 5220 // VQ T& operator--(VQ T&); 5221 // T operator--(VQ T&, int); 5222 void addPlusPlusMinusMinusArithmeticOverloads(OverloadedOperatorKind Op) { 5223 if (!HasArithmeticOrEnumeralCandidateType) 5224 return; 5225 5226 for (unsigned Arith = (Op == OO_PlusPlus? 0 : 1); 5227 Arith < NumArithmeticTypes; ++Arith) { 5228 addPlusPlusMinusMinusStyleOverloads( 5229 getArithmeticType(Arith), 5230 VisibleTypeConversionsQuals.hasVolatile()); 5231 } 5232 } 5233 5234 // C++ [over.built]p5: 5235 // 5236 // For every pair (T, VQ), where T is a cv-qualified or 5237 // cv-unqualified object type, and VQ is either volatile or 5238 // empty, there exist candidate operator functions of the form 5239 // 5240 // T*VQ& operator++(T*VQ&); 5241 // T*VQ& operator--(T*VQ&); 5242 // T* operator++(T*VQ&, int); 5243 // T* operator--(T*VQ&, int); 5244 void addPlusPlusMinusMinusPointerOverloads() { 5245 for (BuiltinCandidateTypeSet::iterator 5246 Ptr = CandidateTypes[0].pointer_begin(), 5247 PtrEnd = CandidateTypes[0].pointer_end(); 5248 Ptr != PtrEnd; ++Ptr) { 5249 // Skip pointer types that aren't pointers to object types. 5250 if (!(*Ptr)->getPointeeType()->isObjectType()) 5251 continue; 5252 5253 addPlusPlusMinusMinusStyleOverloads(*Ptr, 5254 (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5255 VisibleTypeConversionsQuals.hasVolatile())); 5256 } 5257 } 5258 5259 // C++ [over.built]p6: 5260 // For every cv-qualified or cv-unqualified object type T, there 5261 // exist candidate operator functions of the form 5262 // 5263 // T& operator*(T*); 5264 // 5265 // C++ [over.built]p7: 5266 // For every function type T that does not have cv-qualifiers or a 5267 // ref-qualifier, there exist candidate operator functions of the form 5268 // T& operator*(T*); 5269 void addUnaryStarPointerOverloads() { 5270 for (BuiltinCandidateTypeSet::iterator 5271 Ptr = CandidateTypes[0].pointer_begin(), 5272 PtrEnd = CandidateTypes[0].pointer_end(); 5273 Ptr != PtrEnd; ++Ptr) { 5274 QualType ParamTy = *Ptr; 5275 QualType PointeeTy = ParamTy->getPointeeType(); 5276 if (!PointeeTy->isObjectType() && !PointeeTy->isFunctionType()) 5277 continue; 5278 5279 if (const FunctionProtoType *Proto =PointeeTy->getAs<FunctionProtoType>()) 5280 if (Proto->getTypeQuals() || Proto->getRefQualifier()) 5281 continue; 5282 5283 S.AddBuiltinCandidate(S.Context.getLValueReferenceType(PointeeTy), 5284 &ParamTy, Args, 1, CandidateSet); 5285 } 5286 } 5287 5288 // C++ [over.built]p9: 5289 // For every promoted arithmetic type T, there exist candidate 5290 // operator functions of the form 5291 // 5292 // T operator+(T); 5293 // T operator-(T); 5294 void addUnaryPlusOrMinusArithmeticOverloads() { 5295 if (!HasArithmeticOrEnumeralCandidateType) 5296 return; 5297 5298 for (unsigned Arith = FirstPromotedArithmeticType; 5299 Arith < LastPromotedArithmeticType; ++Arith) { 5300 QualType ArithTy = getArithmeticType(Arith); 5301 S.AddBuiltinCandidate(ArithTy, &ArithTy, Args, 1, CandidateSet); 5302 } 5303 5304 // Extension: We also add these operators for vector types. 5305 for (BuiltinCandidateTypeSet::iterator 5306 Vec = CandidateTypes[0].vector_begin(), 5307 VecEnd = CandidateTypes[0].vector_end(); 5308 Vec != VecEnd; ++Vec) { 5309 QualType VecTy = *Vec; 5310 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5311 } 5312 } 5313 5314 // C++ [over.built]p8: 5315 // For every type T, there exist candidate operator functions of 5316 // the form 5317 // 5318 // T* operator+(T*); 5319 void addUnaryPlusPointerOverloads() { 5320 for (BuiltinCandidateTypeSet::iterator 5321 Ptr = CandidateTypes[0].pointer_begin(), 5322 PtrEnd = CandidateTypes[0].pointer_end(); 5323 Ptr != PtrEnd; ++Ptr) { 5324 QualType ParamTy = *Ptr; 5325 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet); 5326 } 5327 } 5328 5329 // C++ [over.built]p10: 5330 // For every promoted integral type T, there exist candidate 5331 // operator functions of the form 5332 // 5333 // T operator~(T); 5334 void addUnaryTildePromotedIntegralOverloads() { 5335 if (!HasArithmeticOrEnumeralCandidateType) 5336 return; 5337 5338 for (unsigned Int = FirstPromotedIntegralType; 5339 Int < LastPromotedIntegralType; ++Int) { 5340 QualType IntTy = getArithmeticType(Int); 5341 S.AddBuiltinCandidate(IntTy, &IntTy, Args, 1, CandidateSet); 5342 } 5343 5344 // Extension: We also add this operator for vector types. 5345 for (BuiltinCandidateTypeSet::iterator 5346 Vec = CandidateTypes[0].vector_begin(), 5347 VecEnd = CandidateTypes[0].vector_end(); 5348 Vec != VecEnd; ++Vec) { 5349 QualType VecTy = *Vec; 5350 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5351 } 5352 } 5353 5354 // C++ [over.match.oper]p16: 5355 // For every pointer to member type T, there exist candidate operator 5356 // functions of the form 5357 // 5358 // bool operator==(T,T); 5359 // bool operator!=(T,T); 5360 void addEqualEqualOrNotEqualMemberPointerOverloads() { 5361 /// Set of (canonical) types that we've already handled. 5362 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5363 5364 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5365 for (BuiltinCandidateTypeSet::iterator 5366 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5367 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5368 MemPtr != MemPtrEnd; 5369 ++MemPtr) { 5370 // Don't add the same builtin candidate twice. 5371 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5372 continue; 5373 5374 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 5375 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5376 CandidateSet); 5377 } 5378 } 5379 } 5380 5381 // C++ [over.built]p15: 5382 // 5383 // For every T, where T is an enumeration type, a pointer type, or 5384 // std::nullptr_t, there exist candidate operator functions of the form 5385 // 5386 // bool operator<(T, T); 5387 // bool operator>(T, T); 5388 // bool operator<=(T, T); 5389 // bool operator>=(T, T); 5390 // bool operator==(T, T); 5391 // bool operator!=(T, T); 5392 void addRelationalPointerOrEnumeralOverloads() { 5393 // C++ [over.built]p1: 5394 // If there is a user-written candidate with the same name and parameter 5395 // types as a built-in candidate operator function, the built-in operator 5396 // function is hidden and is not included in the set of candidate 5397 // functions. 5398 // 5399 // The text is actually in a note, but if we don't implement it then we end 5400 // up with ambiguities when the user provides an overloaded operator for 5401 // an enumeration type. Note that only enumeration types have this problem, 5402 // so we track which enumeration types we've seen operators for. Also, the 5403 // only other overloaded operator with enumeration argumenst, operator=, 5404 // cannot be overloaded for enumeration types, so this is the only place 5405 // where we must suppress candidates like this. 5406 llvm::DenseSet<std::pair<CanQualType, CanQualType> > 5407 UserDefinedBinaryOperators; 5408 5409 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5410 if (CandidateTypes[ArgIdx].enumeration_begin() != 5411 CandidateTypes[ArgIdx].enumeration_end()) { 5412 for (OverloadCandidateSet::iterator C = CandidateSet.begin(), 5413 CEnd = CandidateSet.end(); 5414 C != CEnd; ++C) { 5415 if (!C->Viable || !C->Function || C->Function->getNumParams() != 2) 5416 continue; 5417 5418 QualType FirstParamType = 5419 C->Function->getParamDecl(0)->getType().getUnqualifiedType(); 5420 QualType SecondParamType = 5421 C->Function->getParamDecl(1)->getType().getUnqualifiedType(); 5422 5423 // Skip if either parameter isn't of enumeral type. 5424 if (!FirstParamType->isEnumeralType() || 5425 !SecondParamType->isEnumeralType()) 5426 continue; 5427 5428 // Add this operator to the set of known user-defined operators. 5429 UserDefinedBinaryOperators.insert( 5430 std::make_pair(S.Context.getCanonicalType(FirstParamType), 5431 S.Context.getCanonicalType(SecondParamType))); 5432 } 5433 } 5434 } 5435 5436 /// Set of (canonical) types that we've already handled. 5437 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5438 5439 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5440 for (BuiltinCandidateTypeSet::iterator 5441 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 5442 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 5443 Ptr != PtrEnd; ++Ptr) { 5444 // Don't add the same builtin candidate twice. 5445 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5446 continue; 5447 5448 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5449 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5450 CandidateSet); 5451 } 5452 for (BuiltinCandidateTypeSet::iterator 5453 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5454 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5455 Enum != EnumEnd; ++Enum) { 5456 CanQualType CanonType = S.Context.getCanonicalType(*Enum); 5457 5458 // Don't add the same builtin candidate twice, or if a user defined 5459 // candidate exists. 5460 if (!AddedTypes.insert(CanonType) || 5461 UserDefinedBinaryOperators.count(std::make_pair(CanonType, 5462 CanonType))) 5463 continue; 5464 5465 QualType ParamTypes[2] = { *Enum, *Enum }; 5466 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5467 CandidateSet); 5468 } 5469 5470 if (CandidateTypes[ArgIdx].hasNullPtrType()) { 5471 CanQualType NullPtrTy = S.Context.getCanonicalType(S.Context.NullPtrTy); 5472 if (AddedTypes.insert(NullPtrTy) && 5473 !UserDefinedBinaryOperators.count(std::make_pair(NullPtrTy, 5474 NullPtrTy))) { 5475 QualType ParamTypes[2] = { NullPtrTy, NullPtrTy }; 5476 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5477 CandidateSet); 5478 } 5479 } 5480 } 5481 } 5482 5483 // C++ [over.built]p13: 5484 // 5485 // For every cv-qualified or cv-unqualified object type T 5486 // there exist candidate operator functions of the form 5487 // 5488 // T* operator+(T*, ptrdiff_t); 5489 // T& operator[](T*, ptrdiff_t); [BELOW] 5490 // T* operator-(T*, ptrdiff_t); 5491 // T* operator+(ptrdiff_t, T*); 5492 // T& operator[](ptrdiff_t, T*); [BELOW] 5493 // 5494 // C++ [over.built]p14: 5495 // 5496 // For every T, where T is a pointer to object type, there 5497 // exist candidate operator functions of the form 5498 // 5499 // ptrdiff_t operator-(T, T); 5500 void addBinaryPlusOrMinusPointerOverloads(OverloadedOperatorKind Op) { 5501 /// Set of (canonical) types that we've already handled. 5502 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5503 5504 for (int Arg = 0; Arg < 2; ++Arg) { 5505 QualType AsymetricParamTypes[2] = { 5506 S.Context.getPointerDiffType(), 5507 S.Context.getPointerDiffType(), 5508 }; 5509 for (BuiltinCandidateTypeSet::iterator 5510 Ptr = CandidateTypes[Arg].pointer_begin(), 5511 PtrEnd = CandidateTypes[Arg].pointer_end(); 5512 Ptr != PtrEnd; ++Ptr) { 5513 QualType PointeeTy = (*Ptr)->getPointeeType(); 5514 if (!PointeeTy->isObjectType()) 5515 continue; 5516 5517 AsymetricParamTypes[Arg] = *Ptr; 5518 if (Arg == 0 || Op == OO_Plus) { 5519 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t) 5520 // T* operator+(ptrdiff_t, T*); 5521 S.AddBuiltinCandidate(*Ptr, AsymetricParamTypes, Args, 2, 5522 CandidateSet); 5523 } 5524 if (Op == OO_Minus) { 5525 // ptrdiff_t operator-(T, T); 5526 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5527 continue; 5528 5529 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5530 S.AddBuiltinCandidate(S.Context.getPointerDiffType(), ParamTypes, 5531 Args, 2, CandidateSet); 5532 } 5533 } 5534 } 5535 } 5536 5537 // C++ [over.built]p12: 5538 // 5539 // For every pair of promoted arithmetic types L and R, there 5540 // exist candidate operator functions of the form 5541 // 5542 // LR operator*(L, R); 5543 // LR operator/(L, R); 5544 // LR operator+(L, R); 5545 // LR operator-(L, R); 5546 // bool operator<(L, R); 5547 // bool operator>(L, R); 5548 // bool operator<=(L, R); 5549 // bool operator>=(L, R); 5550 // bool operator==(L, R); 5551 // bool operator!=(L, R); 5552 // 5553 // where LR is the result of the usual arithmetic conversions 5554 // between types L and R. 5555 // 5556 // C++ [over.built]p24: 5557 // 5558 // For every pair of promoted arithmetic types L and R, there exist 5559 // candidate operator functions of the form 5560 // 5561 // LR operator?(bool, L, R); 5562 // 5563 // where LR is the result of the usual arithmetic conversions 5564 // between types L and R. 5565 // Our candidates ignore the first parameter. 5566 void addGenericBinaryArithmeticOverloads(bool isComparison) { 5567 if (!HasArithmeticOrEnumeralCandidateType) 5568 return; 5569 5570 for (unsigned Left = FirstPromotedArithmeticType; 5571 Left < LastPromotedArithmeticType; ++Left) { 5572 for (unsigned Right = FirstPromotedArithmeticType; 5573 Right < LastPromotedArithmeticType; ++Right) { 5574 QualType LandR[2] = { getArithmeticType(Left), 5575 getArithmeticType(Right) }; 5576 QualType Result = 5577 isComparison ? S.Context.BoolTy 5578 : getUsualArithmeticConversions(Left, Right); 5579 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5580 } 5581 } 5582 5583 // Extension: Add the binary operators ==, !=, <, <=, >=, >, *, /, and the 5584 // conditional operator for vector types. 5585 for (BuiltinCandidateTypeSet::iterator 5586 Vec1 = CandidateTypes[0].vector_begin(), 5587 Vec1End = CandidateTypes[0].vector_end(); 5588 Vec1 != Vec1End; ++Vec1) { 5589 for (BuiltinCandidateTypeSet::iterator 5590 Vec2 = CandidateTypes[1].vector_begin(), 5591 Vec2End = CandidateTypes[1].vector_end(); 5592 Vec2 != Vec2End; ++Vec2) { 5593 QualType LandR[2] = { *Vec1, *Vec2 }; 5594 QualType Result = S.Context.BoolTy; 5595 if (!isComparison) { 5596 if ((*Vec1)->isExtVectorType() || !(*Vec2)->isExtVectorType()) 5597 Result = *Vec1; 5598 else 5599 Result = *Vec2; 5600 } 5601 5602 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5603 } 5604 } 5605 } 5606 5607 // C++ [over.built]p17: 5608 // 5609 // For every pair of promoted integral types L and R, there 5610 // exist candidate operator functions of the form 5611 // 5612 // LR operator%(L, R); 5613 // LR operator&(L, R); 5614 // LR operator^(L, R); 5615 // LR operator|(L, R); 5616 // L operator<<(L, R); 5617 // L operator>>(L, R); 5618 // 5619 // where LR is the result of the usual arithmetic conversions 5620 // between types L and R. 5621 void addBinaryBitwiseArithmeticOverloads(OverloadedOperatorKind Op) { 5622 if (!HasArithmeticOrEnumeralCandidateType) 5623 return; 5624 5625 for (unsigned Left = FirstPromotedIntegralType; 5626 Left < LastPromotedIntegralType; ++Left) { 5627 for (unsigned Right = FirstPromotedIntegralType; 5628 Right < LastPromotedIntegralType; ++Right) { 5629 QualType LandR[2] = { getArithmeticType(Left), 5630 getArithmeticType(Right) }; 5631 QualType Result = (Op == OO_LessLess || Op == OO_GreaterGreater) 5632 ? LandR[0] 5633 : getUsualArithmeticConversions(Left, Right); 5634 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5635 } 5636 } 5637 } 5638 5639 // C++ [over.built]p20: 5640 // 5641 // For every pair (T, VQ), where T is an enumeration or 5642 // pointer to member type and VQ is either volatile or 5643 // empty, there exist candidate operator functions of the form 5644 // 5645 // VQ T& operator=(VQ T&, T); 5646 void addAssignmentMemberPointerOrEnumeralOverloads() { 5647 /// Set of (canonical) types that we've already handled. 5648 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5649 5650 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 5651 for (BuiltinCandidateTypeSet::iterator 5652 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5653 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5654 Enum != EnumEnd; ++Enum) { 5655 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 5656 continue; 5657 5658 AddBuiltinAssignmentOperatorCandidates(S, *Enum, Args, 2, 5659 CandidateSet); 5660 } 5661 5662 for (BuiltinCandidateTypeSet::iterator 5663 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5664 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5665 MemPtr != MemPtrEnd; ++MemPtr) { 5666 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5667 continue; 5668 5669 AddBuiltinAssignmentOperatorCandidates(S, *MemPtr, Args, 2, 5670 CandidateSet); 5671 } 5672 } 5673 } 5674 5675 // C++ [over.built]p19: 5676 // 5677 // For every pair (T, VQ), where T is any type and VQ is either 5678 // volatile or empty, there exist candidate operator functions 5679 // of the form 5680 // 5681 // T*VQ& operator=(T*VQ&, T*); 5682 // 5683 // C++ [over.built]p21: 5684 // 5685 // For every pair (T, VQ), where T is a cv-qualified or 5686 // cv-unqualified object type and VQ is either volatile or 5687 // empty, there exist candidate operator functions of the form 5688 // 5689 // T*VQ& operator+=(T*VQ&, ptrdiff_t); 5690 // T*VQ& operator-=(T*VQ&, ptrdiff_t); 5691 void addAssignmentPointerOverloads(bool isEqualOp) { 5692 /// Set of (canonical) types that we've already handled. 5693 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5694 5695 for (BuiltinCandidateTypeSet::iterator 5696 Ptr = CandidateTypes[0].pointer_begin(), 5697 PtrEnd = CandidateTypes[0].pointer_end(); 5698 Ptr != PtrEnd; ++Ptr) { 5699 // If this is operator=, keep track of the builtin candidates we added. 5700 if (isEqualOp) 5701 AddedTypes.insert(S.Context.getCanonicalType(*Ptr)); 5702 else if (!(*Ptr)->getPointeeType()->isObjectType()) 5703 continue; 5704 5705 // non-volatile version 5706 QualType ParamTypes[2] = { 5707 S.Context.getLValueReferenceType(*Ptr), 5708 isEqualOp ? *Ptr : S.Context.getPointerDiffType(), 5709 }; 5710 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5711 /*IsAssigmentOperator=*/ isEqualOp); 5712 5713 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5714 VisibleTypeConversionsQuals.hasVolatile()) { 5715 // volatile version 5716 ParamTypes[0] = 5717 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5718 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5719 /*IsAssigmentOperator=*/isEqualOp); 5720 } 5721 } 5722 5723 if (isEqualOp) { 5724 for (BuiltinCandidateTypeSet::iterator 5725 Ptr = CandidateTypes[1].pointer_begin(), 5726 PtrEnd = CandidateTypes[1].pointer_end(); 5727 Ptr != PtrEnd; ++Ptr) { 5728 // Make sure we don't add the same candidate twice. 5729 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5730 continue; 5731 5732 QualType ParamTypes[2] = { 5733 S.Context.getLValueReferenceType(*Ptr), 5734 *Ptr, 5735 }; 5736 5737 // non-volatile version 5738 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5739 /*IsAssigmentOperator=*/true); 5740 5741 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5742 VisibleTypeConversionsQuals.hasVolatile()) { 5743 // volatile version 5744 ParamTypes[0] = 5745 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5746 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5747 CandidateSet, /*IsAssigmentOperator=*/true); 5748 } 5749 } 5750 } 5751 } 5752 5753 // C++ [over.built]p18: 5754 // 5755 // For every triple (L, VQ, R), where L is an arithmetic type, 5756 // VQ is either volatile or empty, and R is a promoted 5757 // arithmetic type, there exist candidate operator functions of 5758 // the form 5759 // 5760 // VQ L& operator=(VQ L&, R); 5761 // VQ L& operator*=(VQ L&, R); 5762 // VQ L& operator/=(VQ L&, R); 5763 // VQ L& operator+=(VQ L&, R); 5764 // VQ L& operator-=(VQ L&, R); 5765 void addAssignmentArithmeticOverloads(bool isEqualOp) { 5766 if (!HasArithmeticOrEnumeralCandidateType) 5767 return; 5768 5769 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) { 5770 for (unsigned Right = FirstPromotedArithmeticType; 5771 Right < LastPromotedArithmeticType; ++Right) { 5772 QualType ParamTypes[2]; 5773 ParamTypes[1] = getArithmeticType(Right); 5774 5775 // Add this built-in operator as a candidate (VQ is empty). 5776 ParamTypes[0] = 5777 S.Context.getLValueReferenceType(getArithmeticType(Left)); 5778 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5779 /*IsAssigmentOperator=*/isEqualOp); 5780 5781 // Add this built-in operator as a candidate (VQ is 'volatile'). 5782 if (VisibleTypeConversionsQuals.hasVolatile()) { 5783 ParamTypes[0] = 5784 S.Context.getVolatileType(getArithmeticType(Left)); 5785 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5786 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5787 CandidateSet, 5788 /*IsAssigmentOperator=*/isEqualOp); 5789 } 5790 } 5791 } 5792 5793 // Extension: Add the binary operators =, +=, -=, *=, /= for vector types. 5794 for (BuiltinCandidateTypeSet::iterator 5795 Vec1 = CandidateTypes[0].vector_begin(), 5796 Vec1End = CandidateTypes[0].vector_end(); 5797 Vec1 != Vec1End; ++Vec1) { 5798 for (BuiltinCandidateTypeSet::iterator 5799 Vec2 = CandidateTypes[1].vector_begin(), 5800 Vec2End = CandidateTypes[1].vector_end(); 5801 Vec2 != Vec2End; ++Vec2) { 5802 QualType ParamTypes[2]; 5803 ParamTypes[1] = *Vec2; 5804 // Add this built-in operator as a candidate (VQ is empty). 5805 ParamTypes[0] = S.Context.getLValueReferenceType(*Vec1); 5806 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5807 /*IsAssigmentOperator=*/isEqualOp); 5808 5809 // Add this built-in operator as a candidate (VQ is 'volatile'). 5810 if (VisibleTypeConversionsQuals.hasVolatile()) { 5811 ParamTypes[0] = S.Context.getVolatileType(*Vec1); 5812 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5813 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5814 CandidateSet, 5815 /*IsAssigmentOperator=*/isEqualOp); 5816 } 5817 } 5818 } 5819 } 5820 5821 // C++ [over.built]p22: 5822 // 5823 // For every triple (L, VQ, R), where L is an integral type, VQ 5824 // is either volatile or empty, and R is a promoted integral 5825 // type, there exist candidate operator functions of the form 5826 // 5827 // VQ L& operator%=(VQ L&, R); 5828 // VQ L& operator<<=(VQ L&, R); 5829 // VQ L& operator>>=(VQ L&, R); 5830 // VQ L& operator&=(VQ L&, R); 5831 // VQ L& operator^=(VQ L&, R); 5832 // VQ L& operator|=(VQ L&, R); 5833 void addAssignmentIntegralOverloads() { 5834 if (!HasArithmeticOrEnumeralCandidateType) 5835 return; 5836 5837 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) { 5838 for (unsigned Right = FirstPromotedIntegralType; 5839 Right < LastPromotedIntegralType; ++Right) { 5840 QualType ParamTypes[2]; 5841 ParamTypes[1] = getArithmeticType(Right); 5842 5843 // Add this built-in operator as a candidate (VQ is empty). 5844 ParamTypes[0] = 5845 S.Context.getLValueReferenceType(getArithmeticType(Left)); 5846 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 5847 if (VisibleTypeConversionsQuals.hasVolatile()) { 5848 // Add this built-in operator as a candidate (VQ is 'volatile'). 5849 ParamTypes[0] = getArithmeticType(Left); 5850 ParamTypes[0] = S.Context.getVolatileType(ParamTypes[0]); 5851 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5852 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5853 CandidateSet); 5854 } 5855 } 5856 } 5857 } 5858 5859 // C++ [over.operator]p23: 5860 // 5861 // There also exist candidate operator functions of the form 5862 // 5863 // bool operator!(bool); 5864 // bool operator&&(bool, bool); 5865 // bool operator||(bool, bool); 5866 void addExclaimOverload() { 5867 QualType ParamTy = S.Context.BoolTy; 5868 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet, 5869 /*IsAssignmentOperator=*/false, 5870 /*NumContextualBoolArguments=*/1); 5871 } 5872 void addAmpAmpOrPipePipeOverload() { 5873 QualType ParamTypes[2] = { S.Context.BoolTy, S.Context.BoolTy }; 5874 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, CandidateSet, 5875 /*IsAssignmentOperator=*/false, 5876 /*NumContextualBoolArguments=*/2); 5877 } 5878 5879 // C++ [over.built]p13: 5880 // 5881 // For every cv-qualified or cv-unqualified object type T there 5882 // exist candidate operator functions of the form 5883 // 5884 // T* operator+(T*, ptrdiff_t); [ABOVE] 5885 // T& operator[](T*, ptrdiff_t); 5886 // T* operator-(T*, ptrdiff_t); [ABOVE] 5887 // T* operator+(ptrdiff_t, T*); [ABOVE] 5888 // T& operator[](ptrdiff_t, T*); 5889 void addSubscriptOverloads() { 5890 for (BuiltinCandidateTypeSet::iterator 5891 Ptr = CandidateTypes[0].pointer_begin(), 5892 PtrEnd = CandidateTypes[0].pointer_end(); 5893 Ptr != PtrEnd; ++Ptr) { 5894 QualType ParamTypes[2] = { *Ptr, S.Context.getPointerDiffType() }; 5895 QualType PointeeType = (*Ptr)->getPointeeType(); 5896 if (!PointeeType->isObjectType()) 5897 continue; 5898 5899 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 5900 5901 // T& operator[](T*, ptrdiff_t) 5902 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5903 } 5904 5905 for (BuiltinCandidateTypeSet::iterator 5906 Ptr = CandidateTypes[1].pointer_begin(), 5907 PtrEnd = CandidateTypes[1].pointer_end(); 5908 Ptr != PtrEnd; ++Ptr) { 5909 QualType ParamTypes[2] = { S.Context.getPointerDiffType(), *Ptr }; 5910 QualType PointeeType = (*Ptr)->getPointeeType(); 5911 if (!PointeeType->isObjectType()) 5912 continue; 5913 5914 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 5915 5916 // T& operator[](ptrdiff_t, T*) 5917 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5918 } 5919 } 5920 5921 // C++ [over.built]p11: 5922 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type, 5923 // C1 is the same type as C2 or is a derived class of C2, T is an object 5924 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs, 5925 // there exist candidate operator functions of the form 5926 // 5927 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*); 5928 // 5929 // where CV12 is the union of CV1 and CV2. 5930 void addArrowStarOverloads() { 5931 for (BuiltinCandidateTypeSet::iterator 5932 Ptr = CandidateTypes[0].pointer_begin(), 5933 PtrEnd = CandidateTypes[0].pointer_end(); 5934 Ptr != PtrEnd; ++Ptr) { 5935 QualType C1Ty = (*Ptr); 5936 QualType C1; 5937 QualifierCollector Q1; 5938 C1 = QualType(Q1.strip(C1Ty->getPointeeType()), 0); 5939 if (!isa<RecordType>(C1)) 5940 continue; 5941 // heuristic to reduce number of builtin candidates in the set. 5942 // Add volatile/restrict version only if there are conversions to a 5943 // volatile/restrict type. 5944 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile()) 5945 continue; 5946 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict()) 5947 continue; 5948 for (BuiltinCandidateTypeSet::iterator 5949 MemPtr = CandidateTypes[1].member_pointer_begin(), 5950 MemPtrEnd = CandidateTypes[1].member_pointer_end(); 5951 MemPtr != MemPtrEnd; ++MemPtr) { 5952 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr); 5953 QualType C2 = QualType(mptr->getClass(), 0); 5954 C2 = C2.getUnqualifiedType(); 5955 if (C1 != C2 && !S.IsDerivedFrom(C1, C2)) 5956 break; 5957 QualType ParamTypes[2] = { *Ptr, *MemPtr }; 5958 // build CV12 T& 5959 QualType T = mptr->getPointeeType(); 5960 if (!VisibleTypeConversionsQuals.hasVolatile() && 5961 T.isVolatileQualified()) 5962 continue; 5963 if (!VisibleTypeConversionsQuals.hasRestrict() && 5964 T.isRestrictQualified()) 5965 continue; 5966 T = Q1.apply(S.Context, T); 5967 QualType ResultTy = S.Context.getLValueReferenceType(T); 5968 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5969 } 5970 } 5971 } 5972 5973 // Note that we don't consider the first argument, since it has been 5974 // contextually converted to bool long ago. The candidates below are 5975 // therefore added as binary. 5976 // 5977 // C++ [over.built]p25: 5978 // For every type T, where T is a pointer, pointer-to-member, or scoped 5979 // enumeration type, there exist candidate operator functions of the form 5980 // 5981 // T operator?(bool, T, T); 5982 // 5983 void addConditionalOperatorOverloads() { 5984 /// Set of (canonical) types that we've already handled. 5985 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5986 5987 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 5988 for (BuiltinCandidateTypeSet::iterator 5989 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 5990 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 5991 Ptr != PtrEnd; ++Ptr) { 5992 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5993 continue; 5994 5995 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5996 S.AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 5997 } 5998 5999 for (BuiltinCandidateTypeSet::iterator 6000 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 6001 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 6002 MemPtr != MemPtrEnd; ++MemPtr) { 6003 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 6004 continue; 6005 6006 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 6007 S.AddBuiltinCandidate(*MemPtr, ParamTypes, Args, 2, CandidateSet); 6008 } 6009 6010 if (S.getLangOptions().CPlusPlus0x) { 6011 for (BuiltinCandidateTypeSet::iterator 6012 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 6013 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 6014 Enum != EnumEnd; ++Enum) { 6015 if (!(*Enum)->getAs<EnumType>()->getDecl()->isScoped()) 6016 continue; 6017 6018 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 6019 continue; 6020 6021 QualType ParamTypes[2] = { *Enum, *Enum }; 6022 S.AddBuiltinCandidate(*Enum, ParamTypes, Args, 2, CandidateSet); 6023 } 6024 } 6025 } 6026 } 6027}; 6028 6029} // end anonymous namespace 6030 6031/// AddBuiltinOperatorCandidates - Add the appropriate built-in 6032/// operator overloads to the candidate set (C++ [over.built]), based 6033/// on the operator @p Op and the arguments given. For example, if the 6034/// operator is a binary '+', this routine might add "int 6035/// operator+(int, int)" to cover integer addition. 6036void 6037Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op, 6038 SourceLocation OpLoc, 6039 Expr **Args, unsigned NumArgs, 6040 OverloadCandidateSet& CandidateSet) { 6041 // Find all of the types that the arguments can convert to, but only 6042 // if the operator we're looking at has built-in operator candidates 6043 // that make use of these types. Also record whether we encounter non-record 6044 // candidate types or either arithmetic or enumeral candidate types. 6045 Qualifiers VisibleTypeConversionsQuals; 6046 VisibleTypeConversionsQuals.addConst(); 6047 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 6048 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]); 6049 6050 bool HasNonRecordCandidateType = false; 6051 bool HasArithmeticOrEnumeralCandidateType = false; 6052 llvm::SmallVector<BuiltinCandidateTypeSet, 2> CandidateTypes; 6053 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6054 CandidateTypes.push_back(BuiltinCandidateTypeSet(*this)); 6055 CandidateTypes[ArgIdx].AddTypesConvertedFrom(Args[ArgIdx]->getType(), 6056 OpLoc, 6057 true, 6058 (Op == OO_Exclaim || 6059 Op == OO_AmpAmp || 6060 Op == OO_PipePipe), 6061 VisibleTypeConversionsQuals); 6062 HasNonRecordCandidateType = HasNonRecordCandidateType || 6063 CandidateTypes[ArgIdx].hasNonRecordTypes(); 6064 HasArithmeticOrEnumeralCandidateType = 6065 HasArithmeticOrEnumeralCandidateType || 6066 CandidateTypes[ArgIdx].hasArithmeticOrEnumeralTypes(); 6067 } 6068 6069 // Exit early when no non-record types have been added to the candidate set 6070 // for any of the arguments to the operator. 6071 if (!HasNonRecordCandidateType) 6072 return; 6073 6074 // Setup an object to manage the common state for building overloads. 6075 BuiltinOperatorOverloadBuilder OpBuilder(*this, Args, NumArgs, 6076 VisibleTypeConversionsQuals, 6077 HasArithmeticOrEnumeralCandidateType, 6078 CandidateTypes, CandidateSet); 6079 6080 // Dispatch over the operation to add in only those overloads which apply. 6081 switch (Op) { 6082 case OO_None: 6083 case NUM_OVERLOADED_OPERATORS: 6084 assert(false && "Expected an overloaded operator"); 6085 break; 6086 6087 case OO_New: 6088 case OO_Delete: 6089 case OO_Array_New: 6090 case OO_Array_Delete: 6091 case OO_Call: 6092 assert(false && "Special operators don't use AddBuiltinOperatorCandidates"); 6093 break; 6094 6095 case OO_Comma: 6096 case OO_Arrow: 6097 // C++ [over.match.oper]p3: 6098 // -- For the operator ',', the unary operator '&', or the 6099 // operator '->', the built-in candidates set is empty. 6100 break; 6101 6102 case OO_Plus: // '+' is either unary or binary 6103 if (NumArgs == 1) 6104 OpBuilder.addUnaryPlusPointerOverloads(); 6105 // Fall through. 6106 6107 case OO_Minus: // '-' is either unary or binary 6108 if (NumArgs == 1) { 6109 OpBuilder.addUnaryPlusOrMinusArithmeticOverloads(); 6110 } else { 6111 OpBuilder.addBinaryPlusOrMinusPointerOverloads(Op); 6112 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6113 } 6114 break; 6115 6116 case OO_Star: // '*' is either unary or binary 6117 if (NumArgs == 1) 6118 OpBuilder.addUnaryStarPointerOverloads(); 6119 else 6120 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6121 break; 6122 6123 case OO_Slash: 6124 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6125 break; 6126 6127 case OO_PlusPlus: 6128 case OO_MinusMinus: 6129 OpBuilder.addPlusPlusMinusMinusArithmeticOverloads(Op); 6130 OpBuilder.addPlusPlusMinusMinusPointerOverloads(); 6131 break; 6132 6133 case OO_EqualEqual: 6134 case OO_ExclaimEqual: 6135 OpBuilder.addEqualEqualOrNotEqualMemberPointerOverloads(); 6136 // Fall through. 6137 6138 case OO_Less: 6139 case OO_Greater: 6140 case OO_LessEqual: 6141 case OO_GreaterEqual: 6142 OpBuilder.addRelationalPointerOrEnumeralOverloads(); 6143 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/true); 6144 break; 6145 6146 case OO_Percent: 6147 case OO_Caret: 6148 case OO_Pipe: 6149 case OO_LessLess: 6150 case OO_GreaterGreater: 6151 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6152 break; 6153 6154 case OO_Amp: // '&' is either unary or binary 6155 if (NumArgs == 1) 6156 // C++ [over.match.oper]p3: 6157 // -- For the operator ',', the unary operator '&', or the 6158 // operator '->', the built-in candidates set is empty. 6159 break; 6160 6161 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6162 break; 6163 6164 case OO_Tilde: 6165 OpBuilder.addUnaryTildePromotedIntegralOverloads(); 6166 break; 6167 6168 case OO_Equal: 6169 OpBuilder.addAssignmentMemberPointerOrEnumeralOverloads(); 6170 // Fall through. 6171 6172 case OO_PlusEqual: 6173 case OO_MinusEqual: 6174 OpBuilder.addAssignmentPointerOverloads(Op == OO_Equal); 6175 // Fall through. 6176 6177 case OO_StarEqual: 6178 case OO_SlashEqual: 6179 OpBuilder.addAssignmentArithmeticOverloads(Op == OO_Equal); 6180 break; 6181 6182 case OO_PercentEqual: 6183 case OO_LessLessEqual: 6184 case OO_GreaterGreaterEqual: 6185 case OO_AmpEqual: 6186 case OO_CaretEqual: 6187 case OO_PipeEqual: 6188 OpBuilder.addAssignmentIntegralOverloads(); 6189 break; 6190 6191 case OO_Exclaim: 6192 OpBuilder.addExclaimOverload(); 6193 break; 6194 6195 case OO_AmpAmp: 6196 case OO_PipePipe: 6197 OpBuilder.addAmpAmpOrPipePipeOverload(); 6198 break; 6199 6200 case OO_Subscript: 6201 OpBuilder.addSubscriptOverloads(); 6202 break; 6203 6204 case OO_ArrowStar: 6205 OpBuilder.addArrowStarOverloads(); 6206 break; 6207 6208 case OO_Conditional: 6209 OpBuilder.addConditionalOperatorOverloads(); 6210 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6211 break; 6212 } 6213} 6214 6215/// \brief Add function candidates found via argument-dependent lookup 6216/// to the set of overloading candidates. 6217/// 6218/// This routine performs argument-dependent name lookup based on the 6219/// given function name (which may also be an operator name) and adds 6220/// all of the overload candidates found by ADL to the overload 6221/// candidate set (C++ [basic.lookup.argdep]). 6222void 6223Sema::AddArgumentDependentLookupCandidates(DeclarationName Name, 6224 bool Operator, 6225 Expr **Args, unsigned NumArgs, 6226 TemplateArgumentListInfo *ExplicitTemplateArgs, 6227 OverloadCandidateSet& CandidateSet, 6228 bool PartialOverloading, 6229 bool StdNamespaceIsAssociated) { 6230 ADLResult Fns; 6231 6232 // FIXME: This approach for uniquing ADL results (and removing 6233 // redundant candidates from the set) relies on pointer-equality, 6234 // which means we need to key off the canonical decl. However, 6235 // always going back to the canonical decl might not get us the 6236 // right set of default arguments. What default arguments are 6237 // we supposed to consider on ADL candidates, anyway? 6238 6239 // FIXME: Pass in the explicit template arguments? 6240 ArgumentDependentLookup(Name, Operator, Args, NumArgs, Fns, 6241 StdNamespaceIsAssociated); 6242 6243 // Erase all of the candidates we already knew about. 6244 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 6245 CandEnd = CandidateSet.end(); 6246 Cand != CandEnd; ++Cand) 6247 if (Cand->Function) { 6248 Fns.erase(Cand->Function); 6249 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 6250 Fns.erase(FunTmpl); 6251 } 6252 6253 // For each of the ADL candidates we found, add it to the overload 6254 // set. 6255 for (ADLResult::iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 6256 DeclAccessPair FoundDecl = DeclAccessPair::make(*I, AS_none); 6257 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { 6258 if (ExplicitTemplateArgs) 6259 continue; 6260 6261 AddOverloadCandidate(FD, FoundDecl, Args, NumArgs, CandidateSet, 6262 false, PartialOverloading); 6263 } else 6264 AddTemplateOverloadCandidate(cast<FunctionTemplateDecl>(*I), 6265 FoundDecl, ExplicitTemplateArgs, 6266 Args, NumArgs, CandidateSet); 6267 } 6268} 6269 6270/// isBetterOverloadCandidate - Determines whether the first overload 6271/// candidate is a better candidate than the second (C++ 13.3.3p1). 6272bool 6273isBetterOverloadCandidate(Sema &S, 6274 const OverloadCandidate &Cand1, 6275 const OverloadCandidate &Cand2, 6276 SourceLocation Loc, 6277 bool UserDefinedConversion) { 6278 // Define viable functions to be better candidates than non-viable 6279 // functions. 6280 if (!Cand2.Viable) 6281 return Cand1.Viable; 6282 else if (!Cand1.Viable) 6283 return false; 6284 6285 // C++ [over.match.best]p1: 6286 // 6287 // -- if F is a static member function, ICS1(F) is defined such 6288 // that ICS1(F) is neither better nor worse than ICS1(G) for 6289 // any function G, and, symmetrically, ICS1(G) is neither 6290 // better nor worse than ICS1(F). 6291 unsigned StartArg = 0; 6292 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument) 6293 StartArg = 1; 6294 6295 // C++ [over.match.best]p1: 6296 // A viable function F1 is defined to be a better function than another 6297 // viable function F2 if for all arguments i, ICSi(F1) is not a worse 6298 // conversion sequence than ICSi(F2), and then... 6299 unsigned NumArgs = Cand1.Conversions.size(); 6300 assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch"); 6301 bool HasBetterConversion = false; 6302 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) { 6303 switch (CompareImplicitConversionSequences(S, 6304 Cand1.Conversions[ArgIdx], 6305 Cand2.Conversions[ArgIdx])) { 6306 case ImplicitConversionSequence::Better: 6307 // Cand1 has a better conversion sequence. 6308 HasBetterConversion = true; 6309 break; 6310 6311 case ImplicitConversionSequence::Worse: 6312 // Cand1 can't be better than Cand2. 6313 return false; 6314 6315 case ImplicitConversionSequence::Indistinguishable: 6316 // Do nothing. 6317 break; 6318 } 6319 } 6320 6321 // -- for some argument j, ICSj(F1) is a better conversion sequence than 6322 // ICSj(F2), or, if not that, 6323 if (HasBetterConversion) 6324 return true; 6325 6326 // - F1 is a non-template function and F2 is a function template 6327 // specialization, or, if not that, 6328 if ((!Cand1.Function || !Cand1.Function->getPrimaryTemplate()) && 6329 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 6330 return true; 6331 6332 // -- F1 and F2 are function template specializations, and the function 6333 // template for F1 is more specialized than the template for F2 6334 // according to the partial ordering rules described in 14.5.5.2, or, 6335 // if not that, 6336 if (Cand1.Function && Cand1.Function->getPrimaryTemplate() && 6337 Cand2.Function && Cand2.Function->getPrimaryTemplate()) { 6338 if (FunctionTemplateDecl *BetterTemplate 6339 = S.getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(), 6340 Cand2.Function->getPrimaryTemplate(), 6341 Loc, 6342 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion 6343 : TPOC_Call, 6344 Cand1.ExplicitCallArguments)) 6345 return BetterTemplate == Cand1.Function->getPrimaryTemplate(); 6346 } 6347 6348 // -- the context is an initialization by user-defined conversion 6349 // (see 8.5, 13.3.1.5) and the standard conversion sequence 6350 // from the return type of F1 to the destination type (i.e., 6351 // the type of the entity being initialized) is a better 6352 // conversion sequence than the standard conversion sequence 6353 // from the return type of F2 to the destination type. 6354 if (UserDefinedConversion && Cand1.Function && Cand2.Function && 6355 isa<CXXConversionDecl>(Cand1.Function) && 6356 isa<CXXConversionDecl>(Cand2.Function)) { 6357 switch (CompareStandardConversionSequences(S, 6358 Cand1.FinalConversion, 6359 Cand2.FinalConversion)) { 6360 case ImplicitConversionSequence::Better: 6361 // Cand1 has a better conversion sequence. 6362 return true; 6363 6364 case ImplicitConversionSequence::Worse: 6365 // Cand1 can't be better than Cand2. 6366 return false; 6367 6368 case ImplicitConversionSequence::Indistinguishable: 6369 // Do nothing 6370 break; 6371 } 6372 } 6373 6374 return false; 6375} 6376 6377/// \brief Computes the best viable function (C++ 13.3.3) 6378/// within an overload candidate set. 6379/// 6380/// \param CandidateSet the set of candidate functions. 6381/// 6382/// \param Loc the location of the function name (or operator symbol) for 6383/// which overload resolution occurs. 6384/// 6385/// \param Best f overload resolution was successful or found a deleted 6386/// function, Best points to the candidate function found. 6387/// 6388/// \returns The result of overload resolution. 6389OverloadingResult 6390OverloadCandidateSet::BestViableFunction(Sema &S, SourceLocation Loc, 6391 iterator &Best, 6392 bool UserDefinedConversion) { 6393 // Find the best viable function. 6394 Best = end(); 6395 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6396 if (Cand->Viable) 6397 if (Best == end() || isBetterOverloadCandidate(S, *Cand, *Best, Loc, 6398 UserDefinedConversion)) 6399 Best = Cand; 6400 } 6401 6402 // If we didn't find any viable functions, abort. 6403 if (Best == end()) 6404 return OR_No_Viable_Function; 6405 6406 // Make sure that this function is better than every other viable 6407 // function. If not, we have an ambiguity. 6408 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6409 if (Cand->Viable && 6410 Cand != Best && 6411 !isBetterOverloadCandidate(S, *Best, *Cand, Loc, 6412 UserDefinedConversion)) { 6413 Best = end(); 6414 return OR_Ambiguous; 6415 } 6416 } 6417 6418 // Best is the best viable function. 6419 if (Best->Function && 6420 (Best->Function->isDeleted() || Best->Function->isUnavailable())) 6421 return OR_Deleted; 6422 6423 return OR_Success; 6424} 6425 6426namespace { 6427 6428enum OverloadCandidateKind { 6429 oc_function, 6430 oc_method, 6431 oc_constructor, 6432 oc_function_template, 6433 oc_method_template, 6434 oc_constructor_template, 6435 oc_implicit_default_constructor, 6436 oc_implicit_copy_constructor, 6437 oc_implicit_move_constructor, 6438 oc_implicit_copy_assignment, 6439 oc_implicit_move_assignment, 6440 oc_implicit_inherited_constructor 6441}; 6442 6443OverloadCandidateKind ClassifyOverloadCandidate(Sema &S, 6444 FunctionDecl *Fn, 6445 std::string &Description) { 6446 bool isTemplate = false; 6447 6448 if (FunctionTemplateDecl *FunTmpl = Fn->getPrimaryTemplate()) { 6449 isTemplate = true; 6450 Description = S.getTemplateArgumentBindingsText( 6451 FunTmpl->getTemplateParameters(), *Fn->getTemplateSpecializationArgs()); 6452 } 6453 6454 if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn)) { 6455 if (!Ctor->isImplicit()) 6456 return isTemplate ? oc_constructor_template : oc_constructor; 6457 6458 if (Ctor->getInheritedConstructor()) 6459 return oc_implicit_inherited_constructor; 6460 6461 if (Ctor->isDefaultConstructor()) 6462 return oc_implicit_default_constructor; 6463 6464 if (Ctor->isMoveConstructor()) 6465 return oc_implicit_move_constructor; 6466 6467 assert(Ctor->isCopyConstructor() && 6468 "unexpected sort of implicit constructor"); 6469 return oc_implicit_copy_constructor; 6470 } 6471 6472 if (CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Fn)) { 6473 // This actually gets spelled 'candidate function' for now, but 6474 // it doesn't hurt to split it out. 6475 if (!Meth->isImplicit()) 6476 return isTemplate ? oc_method_template : oc_method; 6477 6478 if (Meth->isMoveAssignmentOperator()) 6479 return oc_implicit_move_assignment; 6480 6481 assert(Meth->isCopyAssignmentOperator() 6482 && "implicit method is not copy assignment operator?"); 6483 return oc_implicit_copy_assignment; 6484 } 6485 6486 return isTemplate ? oc_function_template : oc_function; 6487} 6488 6489void MaybeEmitInheritedConstructorNote(Sema &S, FunctionDecl *Fn) { 6490 const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn); 6491 if (!Ctor) return; 6492 6493 Ctor = Ctor->getInheritedConstructor(); 6494 if (!Ctor) return; 6495 6496 S.Diag(Ctor->getLocation(), diag::note_ovl_candidate_inherited_constructor); 6497} 6498 6499} // end anonymous namespace 6500 6501// Notes the location of an overload candidate. 6502void Sema::NoteOverloadCandidate(FunctionDecl *Fn) { 6503 std::string FnDesc; 6504 OverloadCandidateKind K = ClassifyOverloadCandidate(*this, Fn, FnDesc); 6505 Diag(Fn->getLocation(), diag::note_ovl_candidate) 6506 << (unsigned) K << FnDesc; 6507 MaybeEmitInheritedConstructorNote(*this, Fn); 6508} 6509 6510//Notes the location of all overload candidates designated through 6511// OverloadedExpr 6512void Sema::NoteAllOverloadCandidates(Expr* OverloadedExpr) { 6513 assert(OverloadedExpr->getType() == Context.OverloadTy); 6514 6515 OverloadExpr::FindResult Ovl = OverloadExpr::find(OverloadedExpr); 6516 OverloadExpr *OvlExpr = Ovl.Expression; 6517 6518 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 6519 IEnd = OvlExpr->decls_end(); 6520 I != IEnd; ++I) { 6521 if (FunctionTemplateDecl *FunTmpl = 6522 dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()) ) { 6523 NoteOverloadCandidate(FunTmpl->getTemplatedDecl()); 6524 } else if (FunctionDecl *Fun 6525 = dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()) ) { 6526 NoteOverloadCandidate(Fun); 6527 } 6528 } 6529} 6530 6531/// Diagnoses an ambiguous conversion. The partial diagnostic is the 6532/// "lead" diagnostic; it will be given two arguments, the source and 6533/// target types of the conversion. 6534void ImplicitConversionSequence::DiagnoseAmbiguousConversion( 6535 Sema &S, 6536 SourceLocation CaretLoc, 6537 const PartialDiagnostic &PDiag) const { 6538 S.Diag(CaretLoc, PDiag) 6539 << Ambiguous.getFromType() << Ambiguous.getToType(); 6540 for (AmbiguousConversionSequence::const_iterator 6541 I = Ambiguous.begin(), E = Ambiguous.end(); I != E; ++I) { 6542 S.NoteOverloadCandidate(*I); 6543 } 6544} 6545 6546namespace { 6547 6548void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, unsigned I) { 6549 const ImplicitConversionSequence &Conv = Cand->Conversions[I]; 6550 assert(Conv.isBad()); 6551 assert(Cand->Function && "for now, candidate must be a function"); 6552 FunctionDecl *Fn = Cand->Function; 6553 6554 // There's a conversion slot for the object argument if this is a 6555 // non-constructor method. Note that 'I' corresponds the 6556 // conversion-slot index. 6557 bool isObjectArgument = false; 6558 if (isa<CXXMethodDecl>(Fn) && !isa<CXXConstructorDecl>(Fn)) { 6559 if (I == 0) 6560 isObjectArgument = true; 6561 else 6562 I--; 6563 } 6564 6565 std::string FnDesc; 6566 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 6567 6568 Expr *FromExpr = Conv.Bad.FromExpr; 6569 QualType FromTy = Conv.Bad.getFromType(); 6570 QualType ToTy = Conv.Bad.getToType(); 6571 6572 if (FromTy == S.Context.OverloadTy) { 6573 assert(FromExpr && "overload set argument came from implicit argument?"); 6574 Expr *E = FromExpr->IgnoreParens(); 6575 if (isa<UnaryOperator>(E)) 6576 E = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens(); 6577 DeclarationName Name = cast<OverloadExpr>(E)->getName(); 6578 6579 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_overload) 6580 << (unsigned) FnKind << FnDesc 6581 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6582 << ToTy << Name << I+1; 6583 MaybeEmitInheritedConstructorNote(S, Fn); 6584 return; 6585 } 6586 6587 // Do some hand-waving analysis to see if the non-viability is due 6588 // to a qualifier mismatch. 6589 CanQualType CFromTy = S.Context.getCanonicalType(FromTy); 6590 CanQualType CToTy = S.Context.getCanonicalType(ToTy); 6591 if (CanQual<ReferenceType> RT = CToTy->getAs<ReferenceType>()) 6592 CToTy = RT->getPointeeType(); 6593 else { 6594 // TODO: detect and diagnose the full richness of const mismatches. 6595 if (CanQual<PointerType> FromPT = CFromTy->getAs<PointerType>()) 6596 if (CanQual<PointerType> ToPT = CToTy->getAs<PointerType>()) 6597 CFromTy = FromPT->getPointeeType(), CToTy = ToPT->getPointeeType(); 6598 } 6599 6600 if (CToTy.getUnqualifiedType() == CFromTy.getUnqualifiedType() && 6601 !CToTy.isAtLeastAsQualifiedAs(CFromTy)) { 6602 // It is dumb that we have to do this here. 6603 while (isa<ArrayType>(CFromTy)) 6604 CFromTy = CFromTy->getAs<ArrayType>()->getElementType(); 6605 while (isa<ArrayType>(CToTy)) 6606 CToTy = CFromTy->getAs<ArrayType>()->getElementType(); 6607 6608 Qualifiers FromQs = CFromTy.getQualifiers(); 6609 Qualifiers ToQs = CToTy.getQualifiers(); 6610 6611 if (FromQs.getAddressSpace() != ToQs.getAddressSpace()) { 6612 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_addrspace) 6613 << (unsigned) FnKind << FnDesc 6614 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6615 << FromTy 6616 << FromQs.getAddressSpace() << ToQs.getAddressSpace() 6617 << (unsigned) isObjectArgument << I+1; 6618 MaybeEmitInheritedConstructorNote(S, Fn); 6619 return; 6620 } 6621 6622 if (FromQs.getObjCGCAttr() != ToQs.getObjCGCAttr()) { 6623 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_gc) 6624 << (unsigned) FnKind << FnDesc 6625 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6626 << FromTy 6627 << FromQs.getObjCGCAttr() << ToQs.getObjCGCAttr() 6628 << (unsigned) isObjectArgument << I+1; 6629 MaybeEmitInheritedConstructorNote(S, Fn); 6630 return; 6631 } 6632 6633 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 6634 assert(CVR && "unexpected qualifiers mismatch"); 6635 6636 if (isObjectArgument) { 6637 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr_this) 6638 << (unsigned) FnKind << FnDesc 6639 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6640 << FromTy << (CVR - 1); 6641 } else { 6642 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr) 6643 << (unsigned) FnKind << FnDesc 6644 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6645 << FromTy << (CVR - 1) << I+1; 6646 } 6647 MaybeEmitInheritedConstructorNote(S, Fn); 6648 return; 6649 } 6650 6651 // Diagnose references or pointers to incomplete types differently, 6652 // since it's far from impossible that the incompleteness triggered 6653 // the failure. 6654 QualType TempFromTy = FromTy.getNonReferenceType(); 6655 if (const PointerType *PTy = TempFromTy->getAs<PointerType>()) 6656 TempFromTy = PTy->getPointeeType(); 6657 if (TempFromTy->isIncompleteType()) { 6658 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv_incomplete) 6659 << (unsigned) FnKind << FnDesc 6660 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6661 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6662 MaybeEmitInheritedConstructorNote(S, Fn); 6663 return; 6664 } 6665 6666 // Diagnose base -> derived pointer conversions. 6667 unsigned BaseToDerivedConversion = 0; 6668 if (const PointerType *FromPtrTy = FromTy->getAs<PointerType>()) { 6669 if (const PointerType *ToPtrTy = ToTy->getAs<PointerType>()) { 6670 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6671 FromPtrTy->getPointeeType()) && 6672 !FromPtrTy->getPointeeType()->isIncompleteType() && 6673 !ToPtrTy->getPointeeType()->isIncompleteType() && 6674 S.IsDerivedFrom(ToPtrTy->getPointeeType(), 6675 FromPtrTy->getPointeeType())) 6676 BaseToDerivedConversion = 1; 6677 } 6678 } else if (const ObjCObjectPointerType *FromPtrTy 6679 = FromTy->getAs<ObjCObjectPointerType>()) { 6680 if (const ObjCObjectPointerType *ToPtrTy 6681 = ToTy->getAs<ObjCObjectPointerType>()) 6682 if (const ObjCInterfaceDecl *FromIface = FromPtrTy->getInterfaceDecl()) 6683 if (const ObjCInterfaceDecl *ToIface = ToPtrTy->getInterfaceDecl()) 6684 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6685 FromPtrTy->getPointeeType()) && 6686 FromIface->isSuperClassOf(ToIface)) 6687 BaseToDerivedConversion = 2; 6688 } else if (const ReferenceType *ToRefTy = ToTy->getAs<ReferenceType>()) { 6689 if (ToRefTy->getPointeeType().isAtLeastAsQualifiedAs(FromTy) && 6690 !FromTy->isIncompleteType() && 6691 !ToRefTy->getPointeeType()->isIncompleteType() && 6692 S.IsDerivedFrom(ToRefTy->getPointeeType(), FromTy)) 6693 BaseToDerivedConversion = 3; 6694 } 6695 6696 if (BaseToDerivedConversion) { 6697 S.Diag(Fn->getLocation(), 6698 diag::note_ovl_candidate_bad_base_to_derived_conv) 6699 << (unsigned) FnKind << FnDesc 6700 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6701 << (BaseToDerivedConversion - 1) 6702 << FromTy << ToTy << I+1; 6703 MaybeEmitInheritedConstructorNote(S, Fn); 6704 return; 6705 } 6706 6707 // TODO: specialize more based on the kind of mismatch 6708 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv) 6709 << (unsigned) FnKind << FnDesc 6710 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6711 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6712 MaybeEmitInheritedConstructorNote(S, Fn); 6713} 6714 6715void DiagnoseArityMismatch(Sema &S, OverloadCandidate *Cand, 6716 unsigned NumFormalArgs) { 6717 // TODO: treat calls to a missing default constructor as a special case 6718 6719 FunctionDecl *Fn = Cand->Function; 6720 const FunctionProtoType *FnTy = Fn->getType()->getAs<FunctionProtoType>(); 6721 6722 unsigned MinParams = Fn->getMinRequiredArguments(); 6723 6724 // With invalid overloaded operators, it's possible that we think we 6725 // have an arity mismatch when it fact it looks like we have the 6726 // right number of arguments, because only overloaded operators have 6727 // the weird behavior of overloading member and non-member functions. 6728 // Just don't report anything. 6729 if (Fn->isInvalidDecl() && 6730 Fn->getDeclName().getNameKind() == DeclarationName::CXXOperatorName) 6731 return; 6732 6733 // at least / at most / exactly 6734 unsigned mode, modeCount; 6735 if (NumFormalArgs < MinParams) { 6736 assert((Cand->FailureKind == ovl_fail_too_few_arguments) || 6737 (Cand->FailureKind == ovl_fail_bad_deduction && 6738 Cand->DeductionFailure.Result == Sema::TDK_TooFewArguments)); 6739 if (MinParams != FnTy->getNumArgs() || 6740 FnTy->isVariadic() || FnTy->isTemplateVariadic()) 6741 mode = 0; // "at least" 6742 else 6743 mode = 2; // "exactly" 6744 modeCount = MinParams; 6745 } else { 6746 assert((Cand->FailureKind == ovl_fail_too_many_arguments) || 6747 (Cand->FailureKind == ovl_fail_bad_deduction && 6748 Cand->DeductionFailure.Result == Sema::TDK_TooManyArguments)); 6749 if (MinParams != FnTy->getNumArgs()) 6750 mode = 1; // "at most" 6751 else 6752 mode = 2; // "exactly" 6753 modeCount = FnTy->getNumArgs(); 6754 } 6755 6756 std::string Description; 6757 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, Description); 6758 6759 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity) 6760 << (unsigned) FnKind << (Fn->getDescribedFunctionTemplate() != 0) << mode 6761 << modeCount << NumFormalArgs; 6762 MaybeEmitInheritedConstructorNote(S, Fn); 6763} 6764 6765/// Diagnose a failed template-argument deduction. 6766void DiagnoseBadDeduction(Sema &S, OverloadCandidate *Cand, 6767 Expr **Args, unsigned NumArgs) { 6768 FunctionDecl *Fn = Cand->Function; // pattern 6769 6770 TemplateParameter Param = Cand->DeductionFailure.getTemplateParameter(); 6771 NamedDecl *ParamD; 6772 (ParamD = Param.dyn_cast<TemplateTypeParmDecl*>()) || 6773 (ParamD = Param.dyn_cast<NonTypeTemplateParmDecl*>()) || 6774 (ParamD = Param.dyn_cast<TemplateTemplateParmDecl*>()); 6775 switch (Cand->DeductionFailure.Result) { 6776 case Sema::TDK_Success: 6777 llvm_unreachable("TDK_success while diagnosing bad deduction"); 6778 6779 case Sema::TDK_Incomplete: { 6780 assert(ParamD && "no parameter found for incomplete deduction result"); 6781 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_incomplete_deduction) 6782 << ParamD->getDeclName(); 6783 MaybeEmitInheritedConstructorNote(S, Fn); 6784 return; 6785 } 6786 6787 case Sema::TDK_Underqualified: { 6788 assert(ParamD && "no parameter found for bad qualifiers deduction result"); 6789 TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD); 6790 6791 QualType Param = Cand->DeductionFailure.getFirstArg()->getAsType(); 6792 6793 // Param will have been canonicalized, but it should just be a 6794 // qualified version of ParamD, so move the qualifiers to that. 6795 QualifierCollector Qs; 6796 Qs.strip(Param); 6797 QualType NonCanonParam = Qs.apply(S.Context, TParam->getTypeForDecl()); 6798 assert(S.Context.hasSameType(Param, NonCanonParam)); 6799 6800 // Arg has also been canonicalized, but there's nothing we can do 6801 // about that. It also doesn't matter as much, because it won't 6802 // have any template parameters in it (because deduction isn't 6803 // done on dependent types). 6804 QualType Arg = Cand->DeductionFailure.getSecondArg()->getAsType(); 6805 6806 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_underqualified) 6807 << ParamD->getDeclName() << Arg << NonCanonParam; 6808 MaybeEmitInheritedConstructorNote(S, Fn); 6809 return; 6810 } 6811 6812 case Sema::TDK_Inconsistent: { 6813 assert(ParamD && "no parameter found for inconsistent deduction result"); 6814 int which = 0; 6815 if (isa<TemplateTypeParmDecl>(ParamD)) 6816 which = 0; 6817 else if (isa<NonTypeTemplateParmDecl>(ParamD)) 6818 which = 1; 6819 else { 6820 which = 2; 6821 } 6822 6823 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_inconsistent_deduction) 6824 << which << ParamD->getDeclName() 6825 << *Cand->DeductionFailure.getFirstArg() 6826 << *Cand->DeductionFailure.getSecondArg(); 6827 MaybeEmitInheritedConstructorNote(S, Fn); 6828 return; 6829 } 6830 6831 case Sema::TDK_InvalidExplicitArguments: 6832 assert(ParamD && "no parameter found for invalid explicit arguments"); 6833 if (ParamD->getDeclName()) 6834 S.Diag(Fn->getLocation(), 6835 diag::note_ovl_candidate_explicit_arg_mismatch_named) 6836 << ParamD->getDeclName(); 6837 else { 6838 int index = 0; 6839 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ParamD)) 6840 index = TTP->getIndex(); 6841 else if (NonTypeTemplateParmDecl *NTTP 6842 = dyn_cast<NonTypeTemplateParmDecl>(ParamD)) 6843 index = NTTP->getIndex(); 6844 else 6845 index = cast<TemplateTemplateParmDecl>(ParamD)->getIndex(); 6846 S.Diag(Fn->getLocation(), 6847 diag::note_ovl_candidate_explicit_arg_mismatch_unnamed) 6848 << (index + 1); 6849 } 6850 MaybeEmitInheritedConstructorNote(S, Fn); 6851 return; 6852 6853 case Sema::TDK_TooManyArguments: 6854 case Sema::TDK_TooFewArguments: 6855 DiagnoseArityMismatch(S, Cand, NumArgs); 6856 return; 6857 6858 case Sema::TDK_InstantiationDepth: 6859 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_instantiation_depth); 6860 MaybeEmitInheritedConstructorNote(S, Fn); 6861 return; 6862 6863 case Sema::TDK_SubstitutionFailure: { 6864 std::string ArgString; 6865 if (TemplateArgumentList *Args 6866 = Cand->DeductionFailure.getTemplateArgumentList()) 6867 ArgString = S.getTemplateArgumentBindingsText( 6868 Fn->getDescribedFunctionTemplate()->getTemplateParameters(), 6869 *Args); 6870 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_substitution_failure) 6871 << ArgString; 6872 MaybeEmitInheritedConstructorNote(S, Fn); 6873 return; 6874 } 6875 6876 // TODO: diagnose these individually, then kill off 6877 // note_ovl_candidate_bad_deduction, which is uselessly vague. 6878 case Sema::TDK_NonDeducedMismatch: 6879 case Sema::TDK_FailedOverloadResolution: 6880 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_deduction); 6881 MaybeEmitInheritedConstructorNote(S, Fn); 6882 return; 6883 } 6884} 6885 6886/// Generates a 'note' diagnostic for an overload candidate. We've 6887/// already generated a primary error at the call site. 6888/// 6889/// It really does need to be a single diagnostic with its caret 6890/// pointed at the candidate declaration. Yes, this creates some 6891/// major challenges of technical writing. Yes, this makes pointing 6892/// out problems with specific arguments quite awkward. It's still 6893/// better than generating twenty screens of text for every failed 6894/// overload. 6895/// 6896/// It would be great to be able to express per-candidate problems 6897/// more richly for those diagnostic clients that cared, but we'd 6898/// still have to be just as careful with the default diagnostics. 6899void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand, 6900 Expr **Args, unsigned NumArgs) { 6901 FunctionDecl *Fn = Cand->Function; 6902 6903 // Note deleted candidates, but only if they're viable. 6904 if (Cand->Viable && (Fn->isDeleted() || Fn->isUnavailable())) { 6905 std::string FnDesc; 6906 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 6907 6908 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_deleted) 6909 << FnKind << FnDesc << Fn->isDeleted(); 6910 MaybeEmitInheritedConstructorNote(S, Fn); 6911 return; 6912 } 6913 6914 // We don't really have anything else to say about viable candidates. 6915 if (Cand->Viable) { 6916 S.NoteOverloadCandidate(Fn); 6917 return; 6918 } 6919 6920 switch (Cand->FailureKind) { 6921 case ovl_fail_too_many_arguments: 6922 case ovl_fail_too_few_arguments: 6923 return DiagnoseArityMismatch(S, Cand, NumArgs); 6924 6925 case ovl_fail_bad_deduction: 6926 return DiagnoseBadDeduction(S, Cand, Args, NumArgs); 6927 6928 case ovl_fail_trivial_conversion: 6929 case ovl_fail_bad_final_conversion: 6930 case ovl_fail_final_conversion_not_exact: 6931 return S.NoteOverloadCandidate(Fn); 6932 6933 case ovl_fail_bad_conversion: { 6934 unsigned I = (Cand->IgnoreObjectArgument ? 1 : 0); 6935 for (unsigned N = Cand->Conversions.size(); I != N; ++I) 6936 if (Cand->Conversions[I].isBad()) 6937 return DiagnoseBadConversion(S, Cand, I); 6938 6939 // FIXME: this currently happens when we're called from SemaInit 6940 // when user-conversion overload fails. Figure out how to handle 6941 // those conditions and diagnose them well. 6942 return S.NoteOverloadCandidate(Fn); 6943 } 6944 } 6945} 6946 6947void NoteSurrogateCandidate(Sema &S, OverloadCandidate *Cand) { 6948 // Desugar the type of the surrogate down to a function type, 6949 // retaining as many typedefs as possible while still showing 6950 // the function type (and, therefore, its parameter types). 6951 QualType FnType = Cand->Surrogate->getConversionType(); 6952 bool isLValueReference = false; 6953 bool isRValueReference = false; 6954 bool isPointer = false; 6955 if (const LValueReferenceType *FnTypeRef = 6956 FnType->getAs<LValueReferenceType>()) { 6957 FnType = FnTypeRef->getPointeeType(); 6958 isLValueReference = true; 6959 } else if (const RValueReferenceType *FnTypeRef = 6960 FnType->getAs<RValueReferenceType>()) { 6961 FnType = FnTypeRef->getPointeeType(); 6962 isRValueReference = true; 6963 } 6964 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) { 6965 FnType = FnTypePtr->getPointeeType(); 6966 isPointer = true; 6967 } 6968 // Desugar down to a function type. 6969 FnType = QualType(FnType->getAs<FunctionType>(), 0); 6970 // Reconstruct the pointer/reference as appropriate. 6971 if (isPointer) FnType = S.Context.getPointerType(FnType); 6972 if (isRValueReference) FnType = S.Context.getRValueReferenceType(FnType); 6973 if (isLValueReference) FnType = S.Context.getLValueReferenceType(FnType); 6974 6975 S.Diag(Cand->Surrogate->getLocation(), diag::note_ovl_surrogate_cand) 6976 << FnType; 6977 MaybeEmitInheritedConstructorNote(S, Cand->Surrogate); 6978} 6979 6980void NoteBuiltinOperatorCandidate(Sema &S, 6981 const char *Opc, 6982 SourceLocation OpLoc, 6983 OverloadCandidate *Cand) { 6984 assert(Cand->Conversions.size() <= 2 && "builtin operator is not binary"); 6985 std::string TypeStr("operator"); 6986 TypeStr += Opc; 6987 TypeStr += "("; 6988 TypeStr += Cand->BuiltinTypes.ParamTypes[0].getAsString(); 6989 if (Cand->Conversions.size() == 1) { 6990 TypeStr += ")"; 6991 S.Diag(OpLoc, diag::note_ovl_builtin_unary_candidate) << TypeStr; 6992 } else { 6993 TypeStr += ", "; 6994 TypeStr += Cand->BuiltinTypes.ParamTypes[1].getAsString(); 6995 TypeStr += ")"; 6996 S.Diag(OpLoc, diag::note_ovl_builtin_binary_candidate) << TypeStr; 6997 } 6998} 6999 7000void NoteAmbiguousUserConversions(Sema &S, SourceLocation OpLoc, 7001 OverloadCandidate *Cand) { 7002 unsigned NoOperands = Cand->Conversions.size(); 7003 for (unsigned ArgIdx = 0; ArgIdx < NoOperands; ++ArgIdx) { 7004 const ImplicitConversionSequence &ICS = Cand->Conversions[ArgIdx]; 7005 if (ICS.isBad()) break; // all meaningless after first invalid 7006 if (!ICS.isAmbiguous()) continue; 7007 7008 ICS.DiagnoseAmbiguousConversion(S, OpLoc, 7009 S.PDiag(diag::note_ambiguous_type_conversion)); 7010 } 7011} 7012 7013SourceLocation GetLocationForCandidate(const OverloadCandidate *Cand) { 7014 if (Cand->Function) 7015 return Cand->Function->getLocation(); 7016 if (Cand->IsSurrogate) 7017 return Cand->Surrogate->getLocation(); 7018 return SourceLocation(); 7019} 7020 7021struct CompareOverloadCandidatesForDisplay { 7022 Sema &S; 7023 CompareOverloadCandidatesForDisplay(Sema &S) : S(S) {} 7024 7025 bool operator()(const OverloadCandidate *L, 7026 const OverloadCandidate *R) { 7027 // Fast-path this check. 7028 if (L == R) return false; 7029 7030 // Order first by viability. 7031 if (L->Viable) { 7032 if (!R->Viable) return true; 7033 7034 // TODO: introduce a tri-valued comparison for overload 7035 // candidates. Would be more worthwhile if we had a sort 7036 // that could exploit it. 7037 if (isBetterOverloadCandidate(S, *L, *R, SourceLocation())) return true; 7038 if (isBetterOverloadCandidate(S, *R, *L, SourceLocation())) return false; 7039 } else if (R->Viable) 7040 return false; 7041 7042 assert(L->Viable == R->Viable); 7043 7044 // Criteria by which we can sort non-viable candidates: 7045 if (!L->Viable) { 7046 // 1. Arity mismatches come after other candidates. 7047 if (L->FailureKind == ovl_fail_too_many_arguments || 7048 L->FailureKind == ovl_fail_too_few_arguments) 7049 return false; 7050 if (R->FailureKind == ovl_fail_too_many_arguments || 7051 R->FailureKind == ovl_fail_too_few_arguments) 7052 return true; 7053 7054 // 2. Bad conversions come first and are ordered by the number 7055 // of bad conversions and quality of good conversions. 7056 if (L->FailureKind == ovl_fail_bad_conversion) { 7057 if (R->FailureKind != ovl_fail_bad_conversion) 7058 return true; 7059 7060 // If there's any ordering between the defined conversions... 7061 // FIXME: this might not be transitive. 7062 assert(L->Conversions.size() == R->Conversions.size()); 7063 7064 int leftBetter = 0; 7065 unsigned I = (L->IgnoreObjectArgument || R->IgnoreObjectArgument); 7066 for (unsigned E = L->Conversions.size(); I != E; ++I) { 7067 switch (CompareImplicitConversionSequences(S, 7068 L->Conversions[I], 7069 R->Conversions[I])) { 7070 case ImplicitConversionSequence::Better: 7071 leftBetter++; 7072 break; 7073 7074 case ImplicitConversionSequence::Worse: 7075 leftBetter--; 7076 break; 7077 7078 case ImplicitConversionSequence::Indistinguishable: 7079 break; 7080 } 7081 } 7082 if (leftBetter > 0) return true; 7083 if (leftBetter < 0) return false; 7084 7085 } else if (R->FailureKind == ovl_fail_bad_conversion) 7086 return false; 7087 7088 // TODO: others? 7089 } 7090 7091 // Sort everything else by location. 7092 SourceLocation LLoc = GetLocationForCandidate(L); 7093 SourceLocation RLoc = GetLocationForCandidate(R); 7094 7095 // Put candidates without locations (e.g. builtins) at the end. 7096 if (LLoc.isInvalid()) return false; 7097 if (RLoc.isInvalid()) return true; 7098 7099 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc); 7100 } 7101}; 7102 7103/// CompleteNonViableCandidate - Normally, overload resolution only 7104/// computes up to the first 7105void CompleteNonViableCandidate(Sema &S, OverloadCandidate *Cand, 7106 Expr **Args, unsigned NumArgs) { 7107 assert(!Cand->Viable); 7108 7109 // Don't do anything on failures other than bad conversion. 7110 if (Cand->FailureKind != ovl_fail_bad_conversion) return; 7111 7112 // Skip forward to the first bad conversion. 7113 unsigned ConvIdx = (Cand->IgnoreObjectArgument ? 1 : 0); 7114 unsigned ConvCount = Cand->Conversions.size(); 7115 while (true) { 7116 assert(ConvIdx != ConvCount && "no bad conversion in candidate"); 7117 ConvIdx++; 7118 if (Cand->Conversions[ConvIdx - 1].isBad()) 7119 break; 7120 } 7121 7122 if (ConvIdx == ConvCount) 7123 return; 7124 7125 assert(!Cand->Conversions[ConvIdx].isInitialized() && 7126 "remaining conversion is initialized?"); 7127 7128 // FIXME: this should probably be preserved from the overload 7129 // operation somehow. 7130 bool SuppressUserConversions = false; 7131 7132 const FunctionProtoType* Proto; 7133 unsigned ArgIdx = ConvIdx; 7134 7135 if (Cand->IsSurrogate) { 7136 QualType ConvType 7137 = Cand->Surrogate->getConversionType().getNonReferenceType(); 7138 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 7139 ConvType = ConvPtrType->getPointeeType(); 7140 Proto = ConvType->getAs<FunctionProtoType>(); 7141 ArgIdx--; 7142 } else if (Cand->Function) { 7143 Proto = Cand->Function->getType()->getAs<FunctionProtoType>(); 7144 if (isa<CXXMethodDecl>(Cand->Function) && 7145 !isa<CXXConstructorDecl>(Cand->Function)) 7146 ArgIdx--; 7147 } else { 7148 // Builtin binary operator with a bad first conversion. 7149 assert(ConvCount <= 3); 7150 for (; ConvIdx != ConvCount; ++ConvIdx) 7151 Cand->Conversions[ConvIdx] 7152 = TryCopyInitialization(S, Args[ConvIdx], 7153 Cand->BuiltinTypes.ParamTypes[ConvIdx], 7154 SuppressUserConversions, 7155 /*InOverloadResolution*/ true); 7156 return; 7157 } 7158 7159 // Fill in the rest of the conversions. 7160 unsigned NumArgsInProto = Proto->getNumArgs(); 7161 for (; ConvIdx != ConvCount; ++ConvIdx, ++ArgIdx) { 7162 if (ArgIdx < NumArgsInProto) 7163 Cand->Conversions[ConvIdx] 7164 = TryCopyInitialization(S, Args[ArgIdx], Proto->getArgType(ArgIdx), 7165 SuppressUserConversions, 7166 /*InOverloadResolution=*/true); 7167 else 7168 Cand->Conversions[ConvIdx].setEllipsis(); 7169 } 7170} 7171 7172} // end anonymous namespace 7173 7174/// PrintOverloadCandidates - When overload resolution fails, prints 7175/// diagnostic messages containing the candidates in the candidate 7176/// set. 7177void OverloadCandidateSet::NoteCandidates(Sema &S, 7178 OverloadCandidateDisplayKind OCD, 7179 Expr **Args, unsigned NumArgs, 7180 const char *Opc, 7181 SourceLocation OpLoc) { 7182 // Sort the candidates by viability and position. Sorting directly would 7183 // be prohibitive, so we make a set of pointers and sort those. 7184 llvm::SmallVector<OverloadCandidate*, 32> Cands; 7185 if (OCD == OCD_AllCandidates) Cands.reserve(size()); 7186 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) { 7187 if (Cand->Viable) 7188 Cands.push_back(Cand); 7189 else if (OCD == OCD_AllCandidates) { 7190 CompleteNonViableCandidate(S, Cand, Args, NumArgs); 7191 if (Cand->Function || Cand->IsSurrogate) 7192 Cands.push_back(Cand); 7193 // Otherwise, this a non-viable builtin candidate. We do not, in general, 7194 // want to list every possible builtin candidate. 7195 } 7196 } 7197 7198 std::sort(Cands.begin(), Cands.end(), 7199 CompareOverloadCandidatesForDisplay(S)); 7200 7201 bool ReportedAmbiguousConversions = false; 7202 7203 llvm::SmallVectorImpl<OverloadCandidate*>::iterator I, E; 7204 const Diagnostic::OverloadsShown ShowOverloads = S.Diags.getShowOverloads(); 7205 unsigned CandsShown = 0; 7206 for (I = Cands.begin(), E = Cands.end(); I != E; ++I) { 7207 OverloadCandidate *Cand = *I; 7208 7209 // Set an arbitrary limit on the number of candidate functions we'll spam 7210 // the user with. FIXME: This limit should depend on details of the 7211 // candidate list. 7212 if (CandsShown >= 4 && ShowOverloads == Diagnostic::Ovl_Best) { 7213 break; 7214 } 7215 ++CandsShown; 7216 7217 if (Cand->Function) 7218 NoteFunctionCandidate(S, Cand, Args, NumArgs); 7219 else if (Cand->IsSurrogate) 7220 NoteSurrogateCandidate(S, Cand); 7221 else { 7222 assert(Cand->Viable && 7223 "Non-viable built-in candidates are not added to Cands."); 7224 // Generally we only see ambiguities including viable builtin 7225 // operators if overload resolution got screwed up by an 7226 // ambiguous user-defined conversion. 7227 // 7228 // FIXME: It's quite possible for different conversions to see 7229 // different ambiguities, though. 7230 if (!ReportedAmbiguousConversions) { 7231 NoteAmbiguousUserConversions(S, OpLoc, Cand); 7232 ReportedAmbiguousConversions = true; 7233 } 7234 7235 // If this is a viable builtin, print it. 7236 NoteBuiltinOperatorCandidate(S, Opc, OpLoc, Cand); 7237 } 7238 } 7239 7240 if (I != E) 7241 S.Diag(OpLoc, diag::note_ovl_too_many_candidates) << int(E - I); 7242} 7243 7244// [PossiblyAFunctionType] --> [Return] 7245// NonFunctionType --> NonFunctionType 7246// R (A) --> R(A) 7247// R (*)(A) --> R (A) 7248// R (&)(A) --> R (A) 7249// R (S::*)(A) --> R (A) 7250QualType Sema::ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType) { 7251 QualType Ret = PossiblyAFunctionType; 7252 if (const PointerType *ToTypePtr = 7253 PossiblyAFunctionType->getAs<PointerType>()) 7254 Ret = ToTypePtr->getPointeeType(); 7255 else if (const ReferenceType *ToTypeRef = 7256 PossiblyAFunctionType->getAs<ReferenceType>()) 7257 Ret = ToTypeRef->getPointeeType(); 7258 else if (const MemberPointerType *MemTypePtr = 7259 PossiblyAFunctionType->getAs<MemberPointerType>()) 7260 Ret = MemTypePtr->getPointeeType(); 7261 Ret = 7262 Context.getCanonicalType(Ret).getUnqualifiedType(); 7263 return Ret; 7264} 7265 7266// A helper class to help with address of function resolution 7267// - allows us to avoid passing around all those ugly parameters 7268class AddressOfFunctionResolver 7269{ 7270 Sema& S; 7271 Expr* SourceExpr; 7272 const QualType& TargetType; 7273 QualType TargetFunctionType; // Extracted function type from target type 7274 7275 bool Complain; 7276 //DeclAccessPair& ResultFunctionAccessPair; 7277 ASTContext& Context; 7278 7279 bool TargetTypeIsNonStaticMemberFunction; 7280 bool FoundNonTemplateFunction; 7281 7282 OverloadExpr::FindResult OvlExprInfo; 7283 OverloadExpr *OvlExpr; 7284 TemplateArgumentListInfo OvlExplicitTemplateArgs; 7285 llvm::SmallVector<std::pair<DeclAccessPair, FunctionDecl*>, 4> Matches; 7286 7287public: 7288 AddressOfFunctionResolver(Sema &S, Expr* SourceExpr, 7289 const QualType& TargetType, bool Complain) 7290 : S(S), SourceExpr(SourceExpr), TargetType(TargetType), 7291 Complain(Complain), Context(S.getASTContext()), 7292 TargetTypeIsNonStaticMemberFunction( 7293 !!TargetType->getAs<MemberPointerType>()), 7294 FoundNonTemplateFunction(false), 7295 OvlExprInfo(OverloadExpr::find(SourceExpr)), 7296 OvlExpr(OvlExprInfo.Expression) 7297 { 7298 ExtractUnqualifiedFunctionTypeFromTargetType(); 7299 7300 if (!TargetFunctionType->isFunctionType()) { 7301 if (OvlExpr->hasExplicitTemplateArgs()) { 7302 DeclAccessPair dap; 7303 if (FunctionDecl* Fn = S.ResolveSingleFunctionTemplateSpecialization( 7304 OvlExpr, false, &dap) ) { 7305 7306 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7307 if (!Method->isStatic()) { 7308 // If the target type is a non-function type and the function 7309 // found is a non-static member function, pretend as if that was 7310 // the target, it's the only possible type to end up with. 7311 TargetTypeIsNonStaticMemberFunction = true; 7312 7313 // And skip adding the function if its not in the proper form. 7314 // We'll diagnose this due to an empty set of functions. 7315 if (!OvlExprInfo.HasFormOfMemberPointer) 7316 return; 7317 } 7318 } 7319 7320 Matches.push_back(std::make_pair(dap,Fn)); 7321 } 7322 } 7323 return; 7324 } 7325 7326 if (OvlExpr->hasExplicitTemplateArgs()) 7327 OvlExpr->getExplicitTemplateArgs().copyInto(OvlExplicitTemplateArgs); 7328 7329 if (FindAllFunctionsThatMatchTargetTypeExactly()) { 7330 // C++ [over.over]p4: 7331 // If more than one function is selected, [...] 7332 if (Matches.size() > 1) { 7333 if (FoundNonTemplateFunction) 7334 EliminateAllTemplateMatches(); 7335 else 7336 EliminateAllExceptMostSpecializedTemplate(); 7337 } 7338 } 7339 } 7340 7341private: 7342 bool isTargetTypeAFunction() const { 7343 return TargetFunctionType->isFunctionType(); 7344 } 7345 7346 // [ToType] [Return] 7347 7348 // R (*)(A) --> R (A), IsNonStaticMemberFunction = false 7349 // R (&)(A) --> R (A), IsNonStaticMemberFunction = false 7350 // R (S::*)(A) --> R (A), IsNonStaticMemberFunction = true 7351 void inline ExtractUnqualifiedFunctionTypeFromTargetType() { 7352 TargetFunctionType = S.ExtractUnqualifiedFunctionType(TargetType); 7353 } 7354 7355 // return true if any matching specializations were found 7356 bool AddMatchingTemplateFunction(FunctionTemplateDecl* FunctionTemplate, 7357 const DeclAccessPair& CurAccessFunPair) { 7358 if (CXXMethodDecl *Method 7359 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) { 7360 // Skip non-static function templates when converting to pointer, and 7361 // static when converting to member pointer. 7362 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7363 return false; 7364 } 7365 else if (TargetTypeIsNonStaticMemberFunction) 7366 return false; 7367 7368 // C++ [over.over]p2: 7369 // If the name is a function template, template argument deduction is 7370 // done (14.8.2.2), and if the argument deduction succeeds, the 7371 // resulting template argument list is used to generate a single 7372 // function template specialization, which is added to the set of 7373 // overloaded functions considered. 7374 FunctionDecl *Specialization = 0; 7375 TemplateDeductionInfo Info(Context, OvlExpr->getNameLoc()); 7376 if (Sema::TemplateDeductionResult Result 7377 = S.DeduceTemplateArguments(FunctionTemplate, 7378 &OvlExplicitTemplateArgs, 7379 TargetFunctionType, Specialization, 7380 Info)) { 7381 // FIXME: make a note of the failed deduction for diagnostics. 7382 (void)Result; 7383 return false; 7384 } 7385 7386 // Template argument deduction ensures that we have an exact match. 7387 // This function template specicalization works. 7388 Specialization = cast<FunctionDecl>(Specialization->getCanonicalDecl()); 7389 assert(TargetFunctionType 7390 == Context.getCanonicalType(Specialization->getType())); 7391 Matches.push_back(std::make_pair(CurAccessFunPair, Specialization)); 7392 return true; 7393 } 7394 7395 bool AddMatchingNonTemplateFunction(NamedDecl* Fn, 7396 const DeclAccessPair& CurAccessFunPair) { 7397 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7398 // Skip non-static functions when converting to pointer, and static 7399 // when converting to member pointer. 7400 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7401 return false; 7402 } 7403 else if (TargetTypeIsNonStaticMemberFunction) 7404 return false; 7405 7406 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) { 7407 QualType ResultTy; 7408 if (Context.hasSameUnqualifiedType(TargetFunctionType, 7409 FunDecl->getType()) || 7410 IsNoReturnConversion(Context, FunDecl->getType(), TargetFunctionType, 7411 ResultTy)) { 7412 Matches.push_back(std::make_pair(CurAccessFunPair, 7413 cast<FunctionDecl>(FunDecl->getCanonicalDecl()))); 7414 FoundNonTemplateFunction = true; 7415 return true; 7416 } 7417 } 7418 7419 return false; 7420 } 7421 7422 bool FindAllFunctionsThatMatchTargetTypeExactly() { 7423 bool Ret = false; 7424 7425 // If the overload expression doesn't have the form of a pointer to 7426 // member, don't try to convert it to a pointer-to-member type. 7427 if (IsInvalidFormOfPointerToMemberFunction()) 7428 return false; 7429 7430 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 7431 E = OvlExpr->decls_end(); 7432 I != E; ++I) { 7433 // Look through any using declarations to find the underlying function. 7434 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 7435 7436 // C++ [over.over]p3: 7437 // Non-member functions and static member functions match 7438 // targets of type "pointer-to-function" or "reference-to-function." 7439 // Nonstatic member functions match targets of 7440 // type "pointer-to-member-function." 7441 // Note that according to DR 247, the containing class does not matter. 7442 if (FunctionTemplateDecl *FunctionTemplate 7443 = dyn_cast<FunctionTemplateDecl>(Fn)) { 7444 if (AddMatchingTemplateFunction(FunctionTemplate, I.getPair())) 7445 Ret = true; 7446 } 7447 // If we have explicit template arguments supplied, skip non-templates. 7448 else if (!OvlExpr->hasExplicitTemplateArgs() && 7449 AddMatchingNonTemplateFunction(Fn, I.getPair())) 7450 Ret = true; 7451 } 7452 assert(Ret || Matches.empty()); 7453 return Ret; 7454 } 7455 7456 void EliminateAllExceptMostSpecializedTemplate() { 7457 // [...] and any given function template specialization F1 is 7458 // eliminated if the set contains a second function template 7459 // specialization whose function template is more specialized 7460 // than the function template of F1 according to the partial 7461 // ordering rules of 14.5.5.2. 7462 7463 // The algorithm specified above is quadratic. We instead use a 7464 // two-pass algorithm (similar to the one used to identify the 7465 // best viable function in an overload set) that identifies the 7466 // best function template (if it exists). 7467 7468 UnresolvedSet<4> MatchesCopy; // TODO: avoid! 7469 for (unsigned I = 0, E = Matches.size(); I != E; ++I) 7470 MatchesCopy.addDecl(Matches[I].second, Matches[I].first.getAccess()); 7471 7472 UnresolvedSetIterator Result = 7473 S.getMostSpecialized(MatchesCopy.begin(), MatchesCopy.end(), 7474 TPOC_Other, 0, SourceExpr->getLocStart(), 7475 S.PDiag(), 7476 S.PDiag(diag::err_addr_ovl_ambiguous) 7477 << Matches[0].second->getDeclName(), 7478 S.PDiag(diag::note_ovl_candidate) 7479 << (unsigned) oc_function_template, 7480 Complain); 7481 7482 if (Result != MatchesCopy.end()) { 7483 // Make it the first and only element 7484 Matches[0].first = Matches[Result - MatchesCopy.begin()].first; 7485 Matches[0].second = cast<FunctionDecl>(*Result); 7486 Matches.resize(1); 7487 } 7488 } 7489 7490 void EliminateAllTemplateMatches() { 7491 // [...] any function template specializations in the set are 7492 // eliminated if the set also contains a non-template function, [...] 7493 for (unsigned I = 0, N = Matches.size(); I != N; ) { 7494 if (Matches[I].second->getPrimaryTemplate() == 0) 7495 ++I; 7496 else { 7497 Matches[I] = Matches[--N]; 7498 Matches.set_size(N); 7499 } 7500 } 7501 } 7502 7503public: 7504 void ComplainNoMatchesFound() const { 7505 assert(Matches.empty()); 7506 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_no_viable) 7507 << OvlExpr->getName() << TargetFunctionType 7508 << OvlExpr->getSourceRange(); 7509 S.NoteAllOverloadCandidates(OvlExpr); 7510 } 7511 7512 bool IsInvalidFormOfPointerToMemberFunction() const { 7513 return TargetTypeIsNonStaticMemberFunction && 7514 !OvlExprInfo.HasFormOfMemberPointer; 7515 } 7516 7517 void ComplainIsInvalidFormOfPointerToMemberFunction() const { 7518 // TODO: Should we condition this on whether any functions might 7519 // have matched, or is it more appropriate to do that in callers? 7520 // TODO: a fixit wouldn't hurt. 7521 S.Diag(OvlExpr->getNameLoc(), diag::err_addr_ovl_no_qualifier) 7522 << TargetType << OvlExpr->getSourceRange(); 7523 } 7524 7525 void ComplainOfInvalidConversion() const { 7526 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_not_func_ptrref) 7527 << OvlExpr->getName() << TargetType; 7528 } 7529 7530 void ComplainMultipleMatchesFound() const { 7531 assert(Matches.size() > 1); 7532 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_ambiguous) 7533 << OvlExpr->getName() 7534 << OvlExpr->getSourceRange(); 7535 S.NoteAllOverloadCandidates(OvlExpr); 7536 } 7537 7538 int getNumMatches() const { return Matches.size(); } 7539 7540 FunctionDecl* getMatchingFunctionDecl() const { 7541 if (Matches.size() != 1) return 0; 7542 return Matches[0].second; 7543 } 7544 7545 const DeclAccessPair* getMatchingFunctionAccessPair() const { 7546 if (Matches.size() != 1) return 0; 7547 return &Matches[0].first; 7548 } 7549}; 7550 7551/// ResolveAddressOfOverloadedFunction - Try to resolve the address of 7552/// an overloaded function (C++ [over.over]), where @p From is an 7553/// expression with overloaded function type and @p ToType is the type 7554/// we're trying to resolve to. For example: 7555/// 7556/// @code 7557/// int f(double); 7558/// int f(int); 7559/// 7560/// int (*pfd)(double) = f; // selects f(double) 7561/// @endcode 7562/// 7563/// This routine returns the resulting FunctionDecl if it could be 7564/// resolved, and NULL otherwise. When @p Complain is true, this 7565/// routine will emit diagnostics if there is an error. 7566FunctionDecl * 7567Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr, QualType TargetType, 7568 bool Complain, 7569 DeclAccessPair &FoundResult) { 7570 7571 assert(AddressOfExpr->getType() == Context.OverloadTy); 7572 7573 AddressOfFunctionResolver Resolver(*this, AddressOfExpr, TargetType, Complain); 7574 int NumMatches = Resolver.getNumMatches(); 7575 FunctionDecl* Fn = 0; 7576 if ( NumMatches == 0 && Complain) { 7577 if (Resolver.IsInvalidFormOfPointerToMemberFunction()) 7578 Resolver.ComplainIsInvalidFormOfPointerToMemberFunction(); 7579 else 7580 Resolver.ComplainNoMatchesFound(); 7581 } 7582 else if (NumMatches > 1 && Complain) 7583 Resolver.ComplainMultipleMatchesFound(); 7584 else if (NumMatches == 1) { 7585 Fn = Resolver.getMatchingFunctionDecl(); 7586 assert(Fn); 7587 FoundResult = *Resolver.getMatchingFunctionAccessPair(); 7588 MarkDeclarationReferenced(AddressOfExpr->getLocStart(), Fn); 7589 if (Complain) 7590 CheckAddressOfMemberAccess(AddressOfExpr, FoundResult); 7591 } 7592 7593 return Fn; 7594} 7595 7596/// \brief Given an expression that refers to an overloaded function, try to 7597/// resolve that overloaded function expression down to a single function. 7598/// 7599/// This routine can only resolve template-ids that refer to a single function 7600/// template, where that template-id refers to a single template whose template 7601/// arguments are either provided by the template-id or have defaults, 7602/// as described in C++0x [temp.arg.explicit]p3. 7603FunctionDecl * 7604Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, 7605 bool Complain, 7606 DeclAccessPair *FoundResult) { 7607 // C++ [over.over]p1: 7608 // [...] [Note: any redundant set of parentheses surrounding the 7609 // overloaded function name is ignored (5.1). ] 7610 // C++ [over.over]p1: 7611 // [...] The overloaded function name can be preceded by the & 7612 // operator. 7613 7614 // If we didn't actually find any template-ids, we're done. 7615 if (!ovl->hasExplicitTemplateArgs()) 7616 return 0; 7617 7618 TemplateArgumentListInfo ExplicitTemplateArgs; 7619 ovl->getExplicitTemplateArgs().copyInto(ExplicitTemplateArgs); 7620 7621 // Look through all of the overloaded functions, searching for one 7622 // whose type matches exactly. 7623 FunctionDecl *Matched = 0; 7624 for (UnresolvedSetIterator I = ovl->decls_begin(), 7625 E = ovl->decls_end(); I != E; ++I) { 7626 // C++0x [temp.arg.explicit]p3: 7627 // [...] In contexts where deduction is done and fails, or in contexts 7628 // where deduction is not done, if a template argument list is 7629 // specified and it, along with any default template arguments, 7630 // identifies a single function template specialization, then the 7631 // template-id is an lvalue for the function template specialization. 7632 FunctionTemplateDecl *FunctionTemplate 7633 = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()); 7634 7635 // C++ [over.over]p2: 7636 // If the name is a function template, template argument deduction is 7637 // done (14.8.2.2), and if the argument deduction succeeds, the 7638 // resulting template argument list is used to generate a single 7639 // function template specialization, which is added to the set of 7640 // overloaded functions considered. 7641 FunctionDecl *Specialization = 0; 7642 TemplateDeductionInfo Info(Context, ovl->getNameLoc()); 7643 if (TemplateDeductionResult Result 7644 = DeduceTemplateArguments(FunctionTemplate, &ExplicitTemplateArgs, 7645 Specialization, Info)) { 7646 // FIXME: make a note of the failed deduction for diagnostics. 7647 (void)Result; 7648 continue; 7649 } 7650 7651 assert(Specialization && "no specialization and no error?"); 7652 7653 // Multiple matches; we can't resolve to a single declaration. 7654 if (Matched) { 7655 if (Complain) { 7656 Diag(ovl->getExprLoc(), diag::err_addr_ovl_ambiguous) 7657 << ovl->getName(); 7658 NoteAllOverloadCandidates(ovl); 7659 } 7660 return 0; 7661 } 7662 7663 Matched = Specialization; 7664 if (FoundResult) *FoundResult = I.getPair(); 7665 } 7666 7667 return Matched; 7668} 7669 7670 7671 7672 7673// Resolve and fix an overloaded expression that 7674// can be resolved because it identifies a single function 7675// template specialization 7676// Last three arguments should only be supplied if Complain = true 7677ExprResult Sema::ResolveAndFixSingleFunctionTemplateSpecialization( 7678 Expr *SrcExpr, bool doFunctionPointerConverion, bool complain, 7679 const SourceRange& OpRangeForComplaining, 7680 QualType DestTypeForComplaining, 7681 unsigned DiagIDForComplaining) { 7682 assert(SrcExpr->getType() == Context.OverloadTy); 7683 7684 OverloadExpr::FindResult ovl = OverloadExpr::find(SrcExpr); 7685 7686 DeclAccessPair found; 7687 ExprResult SingleFunctionExpression; 7688 if (FunctionDecl *fn = ResolveSingleFunctionTemplateSpecialization( 7689 ovl.Expression, /*complain*/ false, &found)) { 7690 if (DiagnoseUseOfDecl(fn, SrcExpr->getSourceRange().getBegin())) 7691 return ExprError(); 7692 7693 // It is only correct to resolve to an instance method if we're 7694 // resolving a form that's permitted to be a pointer to member. 7695 // Otherwise we'll end up making a bound member expression, which 7696 // is illegal in all the contexts we resolve like this. 7697 if (!ovl.HasFormOfMemberPointer && 7698 isa<CXXMethodDecl>(fn) && 7699 cast<CXXMethodDecl>(fn)->isInstance()) { 7700 if (complain) { 7701 Diag(ovl.Expression->getExprLoc(), 7702 diag::err_invalid_use_of_bound_member_func) 7703 << ovl.Expression->getSourceRange(); 7704 // TODO: I believe we only end up here if there's a mix of 7705 // static and non-static candidates (otherwise the expression 7706 // would have 'bound member' type, not 'overload' type). 7707 // Ideally we would note which candidate was chosen and why 7708 // the static candidates were rejected. 7709 } 7710 7711 return ExprError(); 7712 } 7713 7714 // Fix the expresion to refer to 'fn'. 7715 SingleFunctionExpression = 7716 Owned(FixOverloadedFunctionReference(SrcExpr, found, fn)); 7717 7718 // If desired, do function-to-pointer decay. 7719 if (doFunctionPointerConverion) 7720 SingleFunctionExpression = 7721 DefaultFunctionArrayLvalueConversion(SingleFunctionExpression.take()); 7722 } 7723 7724 if (!SingleFunctionExpression.isUsable()) { 7725 if (complain) { 7726 Diag(OpRangeForComplaining.getBegin(), DiagIDForComplaining) 7727 << ovl.Expression->getName() 7728 << DestTypeForComplaining 7729 << OpRangeForComplaining 7730 << ovl.Expression->getQualifierLoc().getSourceRange(); 7731 NoteAllOverloadCandidates(SrcExpr); 7732 } 7733 return ExprError(); 7734 } 7735 7736 return SingleFunctionExpression; 7737} 7738 7739/// \brief Add a single candidate to the overload set. 7740static void AddOverloadedCallCandidate(Sema &S, 7741 DeclAccessPair FoundDecl, 7742 TemplateArgumentListInfo *ExplicitTemplateArgs, 7743 Expr **Args, unsigned NumArgs, 7744 OverloadCandidateSet &CandidateSet, 7745 bool PartialOverloading) { 7746 NamedDecl *Callee = FoundDecl.getDecl(); 7747 if (isa<UsingShadowDecl>(Callee)) 7748 Callee = cast<UsingShadowDecl>(Callee)->getTargetDecl(); 7749 7750 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) { 7751 assert(!ExplicitTemplateArgs && "Explicit template arguments?"); 7752 S.AddOverloadCandidate(Func, FoundDecl, Args, NumArgs, CandidateSet, 7753 false, PartialOverloading); 7754 return; 7755 } 7756 7757 if (FunctionTemplateDecl *FuncTemplate 7758 = dyn_cast<FunctionTemplateDecl>(Callee)) { 7759 S.AddTemplateOverloadCandidate(FuncTemplate, FoundDecl, 7760 ExplicitTemplateArgs, 7761 Args, NumArgs, CandidateSet); 7762 return; 7763 } 7764 7765 assert(false && "unhandled case in overloaded call candidate"); 7766 7767 // do nothing? 7768} 7769 7770/// \brief Add the overload candidates named by callee and/or found by argument 7771/// dependent lookup to the given overload set. 7772void Sema::AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE, 7773 Expr **Args, unsigned NumArgs, 7774 OverloadCandidateSet &CandidateSet, 7775 bool PartialOverloading) { 7776 7777#ifndef NDEBUG 7778 // Verify that ArgumentDependentLookup is consistent with the rules 7779 // in C++0x [basic.lookup.argdep]p3: 7780 // 7781 // Let X be the lookup set produced by unqualified lookup (3.4.1) 7782 // and let Y be the lookup set produced by argument dependent 7783 // lookup (defined as follows). If X contains 7784 // 7785 // -- a declaration of a class member, or 7786 // 7787 // -- a block-scope function declaration that is not a 7788 // using-declaration, or 7789 // 7790 // -- a declaration that is neither a function or a function 7791 // template 7792 // 7793 // then Y is empty. 7794 7795 if (ULE->requiresADL()) { 7796 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 7797 E = ULE->decls_end(); I != E; ++I) { 7798 assert(!(*I)->getDeclContext()->isRecord()); 7799 assert(isa<UsingShadowDecl>(*I) || 7800 !(*I)->getDeclContext()->isFunctionOrMethod()); 7801 assert((*I)->getUnderlyingDecl()->isFunctionOrFunctionTemplate()); 7802 } 7803 } 7804#endif 7805 7806 // It would be nice to avoid this copy. 7807 TemplateArgumentListInfo TABuffer; 7808 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 7809 if (ULE->hasExplicitTemplateArgs()) { 7810 ULE->copyTemplateArgumentsInto(TABuffer); 7811 ExplicitTemplateArgs = &TABuffer; 7812 } 7813 7814 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 7815 E = ULE->decls_end(); I != E; ++I) 7816 AddOverloadedCallCandidate(*this, I.getPair(), ExplicitTemplateArgs, 7817 Args, NumArgs, CandidateSet, 7818 PartialOverloading); 7819 7820 if (ULE->requiresADL()) 7821 AddArgumentDependentLookupCandidates(ULE->getName(), /*Operator*/ false, 7822 Args, NumArgs, 7823 ExplicitTemplateArgs, 7824 CandidateSet, 7825 PartialOverloading, 7826 ULE->isStdAssociatedNamespace()); 7827} 7828 7829/// Attempt to recover from an ill-formed use of a non-dependent name in a 7830/// template, where the non-dependent name was declared after the template 7831/// was defined. This is common in code written for a compilers which do not 7832/// correctly implement two-stage name lookup. 7833/// 7834/// Returns true if a viable candidate was found and a diagnostic was issued. 7835static bool 7836DiagnoseTwoPhaseLookup(Sema &SemaRef, SourceLocation FnLoc, 7837 const CXXScopeSpec &SS, LookupResult &R, 7838 TemplateArgumentListInfo *ExplicitTemplateArgs, 7839 Expr **Args, unsigned NumArgs) { 7840 if (SemaRef.ActiveTemplateInstantiations.empty() || !SS.isEmpty()) 7841 return false; 7842 7843 for (DeclContext *DC = SemaRef.CurContext; DC; DC = DC->getParent()) { 7844 SemaRef.LookupQualifiedName(R, DC); 7845 7846 if (!R.empty()) { 7847 R.suppressDiagnostics(); 7848 7849 if (isa<CXXRecordDecl>(DC)) { 7850 // Don't diagnose names we find in classes; we get much better 7851 // diagnostics for these from DiagnoseEmptyLookup. 7852 R.clear(); 7853 return false; 7854 } 7855 7856 OverloadCandidateSet Candidates(FnLoc); 7857 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 7858 AddOverloadedCallCandidate(SemaRef, I.getPair(), 7859 ExplicitTemplateArgs, Args, NumArgs, 7860 Candidates, false); 7861 7862 OverloadCandidateSet::iterator Best; 7863 if (Candidates.BestViableFunction(SemaRef, FnLoc, Best) != OR_Success) 7864 // No viable functions. Don't bother the user with notes for functions 7865 // which don't work and shouldn't be found anyway. 7866 return false; 7867 7868 // Find the namespaces where ADL would have looked, and suggest 7869 // declaring the function there instead. 7870 Sema::AssociatedNamespaceSet AssociatedNamespaces; 7871 Sema::AssociatedClassSet AssociatedClasses; 7872 SemaRef.FindAssociatedClassesAndNamespaces(Args, NumArgs, 7873 AssociatedNamespaces, 7874 AssociatedClasses); 7875 // Never suggest declaring a function within namespace 'std'. 7876 Sema::AssociatedNamespaceSet SuggestedNamespaces; 7877 if (DeclContext *Std = SemaRef.getStdNamespace()) { 7878 for (Sema::AssociatedNamespaceSet::iterator 7879 it = AssociatedNamespaces.begin(), 7880 end = AssociatedNamespaces.end(); it != end; ++it) { 7881 if (!Std->Encloses(*it)) 7882 SuggestedNamespaces.insert(*it); 7883 } 7884 } 7885 7886 SemaRef.Diag(R.getNameLoc(), diag::err_not_found_by_two_phase_lookup) 7887 << R.getLookupName(); 7888 if (SuggestedNamespaces.empty()) { 7889 SemaRef.Diag(Best->Function->getLocation(), 7890 diag::note_not_found_by_two_phase_lookup) 7891 << R.getLookupName() << 0; 7892 } else if (SuggestedNamespaces.size() == 1) { 7893 SemaRef.Diag(Best->Function->getLocation(), 7894 diag::note_not_found_by_two_phase_lookup) 7895 << R.getLookupName() << 1 << *SuggestedNamespaces.begin(); 7896 } else { 7897 // FIXME: It would be useful to list the associated namespaces here, 7898 // but the diagnostics infrastructure doesn't provide a way to produce 7899 // a localized representation of a list of items. 7900 SemaRef.Diag(Best->Function->getLocation(), 7901 diag::note_not_found_by_two_phase_lookup) 7902 << R.getLookupName() << 2; 7903 } 7904 7905 // Try to recover by calling this function. 7906 return true; 7907 } 7908 7909 R.clear(); 7910 } 7911 7912 return false; 7913} 7914 7915/// Attempt to recover from ill-formed use of a non-dependent operator in a 7916/// template, where the non-dependent operator was declared after the template 7917/// was defined. 7918/// 7919/// Returns true if a viable candidate was found and a diagnostic was issued. 7920static bool 7921DiagnoseTwoPhaseOperatorLookup(Sema &SemaRef, OverloadedOperatorKind Op, 7922 SourceLocation OpLoc, 7923 Expr **Args, unsigned NumArgs) { 7924 DeclarationName OpName = 7925 SemaRef.Context.DeclarationNames.getCXXOperatorName(Op); 7926 LookupResult R(SemaRef, OpName, OpLoc, Sema::LookupOperatorName); 7927 return DiagnoseTwoPhaseLookup(SemaRef, OpLoc, CXXScopeSpec(), R, 7928 /*ExplicitTemplateArgs=*/0, Args, NumArgs); 7929} 7930 7931/// Attempts to recover from a call where no functions were found. 7932/// 7933/// Returns true if new candidates were found. 7934static ExprResult 7935BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn, 7936 UnresolvedLookupExpr *ULE, 7937 SourceLocation LParenLoc, 7938 Expr **Args, unsigned NumArgs, 7939 SourceLocation RParenLoc, 7940 bool EmptyLookup) { 7941 7942 CXXScopeSpec SS; 7943 SS.Adopt(ULE->getQualifierLoc()); 7944 7945 TemplateArgumentListInfo TABuffer; 7946 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 7947 if (ULE->hasExplicitTemplateArgs()) { 7948 ULE->copyTemplateArgumentsInto(TABuffer); 7949 ExplicitTemplateArgs = &TABuffer; 7950 } 7951 7952 LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(), 7953 Sema::LookupOrdinaryName); 7954 if (!DiagnoseTwoPhaseLookup(SemaRef, Fn->getExprLoc(), SS, R, 7955 ExplicitTemplateArgs, Args, NumArgs) && 7956 (!EmptyLookup || 7957 SemaRef.DiagnoseEmptyLookup(S, SS, R, Sema::CTC_Expression))) 7958 return ExprError(); 7959 7960 assert(!R.empty() && "lookup results empty despite recovery"); 7961 7962 // Build an implicit member call if appropriate. Just drop the 7963 // casts and such from the call, we don't really care. 7964 ExprResult NewFn = ExprError(); 7965 if ((*R.begin())->isCXXClassMember()) 7966 NewFn = SemaRef.BuildPossibleImplicitMemberExpr(SS, R, 7967 ExplicitTemplateArgs); 7968 else if (ExplicitTemplateArgs) 7969 NewFn = SemaRef.BuildTemplateIdExpr(SS, R, false, *ExplicitTemplateArgs); 7970 else 7971 NewFn = SemaRef.BuildDeclarationNameExpr(SS, R, false); 7972 7973 if (NewFn.isInvalid()) 7974 return ExprError(); 7975 7976 // This shouldn't cause an infinite loop because we're giving it 7977 // an expression with viable lookup results, which should never 7978 // end up here. 7979 return SemaRef.ActOnCallExpr(/*Scope*/ 0, NewFn.take(), LParenLoc, 7980 MultiExprArg(Args, NumArgs), RParenLoc); 7981} 7982 7983/// ResolveOverloadedCallFn - Given the call expression that calls Fn 7984/// (which eventually refers to the declaration Func) and the call 7985/// arguments Args/NumArgs, attempt to resolve the function call down 7986/// to a specific function. If overload resolution succeeds, returns 7987/// the function declaration produced by overload 7988/// resolution. Otherwise, emits diagnostics, deletes all of the 7989/// arguments and Fn, and returns NULL. 7990ExprResult 7991Sema::BuildOverloadedCallExpr(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE, 7992 SourceLocation LParenLoc, 7993 Expr **Args, unsigned NumArgs, 7994 SourceLocation RParenLoc, 7995 Expr *ExecConfig) { 7996#ifndef NDEBUG 7997 if (ULE->requiresADL()) { 7998 // To do ADL, we must have found an unqualified name. 7999 assert(!ULE->getQualifier() && "qualified name with ADL"); 8000 8001 // We don't perform ADL for implicit declarations of builtins. 8002 // Verify that this was correctly set up. 8003 FunctionDecl *F; 8004 if (ULE->decls_begin() + 1 == ULE->decls_end() && 8005 (F = dyn_cast<FunctionDecl>(*ULE->decls_begin())) && 8006 F->getBuiltinID() && F->isImplicit()) 8007 assert(0 && "performing ADL for builtin"); 8008 8009 // We don't perform ADL in C. 8010 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 8011 } else 8012 assert(!ULE->isStdAssociatedNamespace() && 8013 "std is associated namespace but not doing ADL"); 8014#endif 8015 8016 OverloadCandidateSet CandidateSet(Fn->getExprLoc()); 8017 8018 // Add the functions denoted by the callee to the set of candidate 8019 // functions, including those from argument-dependent lookup. 8020 AddOverloadedCallCandidates(ULE, Args, NumArgs, CandidateSet); 8021 8022 // If we found nothing, try to recover. 8023 // BuildRecoveryCallExpr diagnoses the error itself, so we just bail 8024 // out if it fails. 8025 if (CandidateSet.empty()) 8026 return BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, Args, NumArgs, 8027 RParenLoc, /*EmptyLookup=*/true); 8028 8029 OverloadCandidateSet::iterator Best; 8030 switch (CandidateSet.BestViableFunction(*this, Fn->getLocStart(), Best)) { 8031 case OR_Success: { 8032 FunctionDecl *FDecl = Best->Function; 8033 MarkDeclarationReferenced(Fn->getExprLoc(), FDecl); 8034 CheckUnresolvedLookupAccess(ULE, Best->FoundDecl); 8035 DiagnoseUseOfDecl(FDecl? FDecl : Best->FoundDecl.getDecl(), 8036 ULE->getNameLoc()); 8037 Fn = FixOverloadedFunctionReference(Fn, Best->FoundDecl, FDecl); 8038 return BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, RParenLoc, 8039 ExecConfig); 8040 } 8041 8042 case OR_No_Viable_Function: { 8043 // Try to recover by looking for viable functions which the user might 8044 // have meant to call. 8045 ExprResult Recovery = BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, 8046 Args, NumArgs, RParenLoc, 8047 /*EmptyLookup=*/false); 8048 if (!Recovery.isInvalid()) 8049 return Recovery; 8050 8051 Diag(Fn->getSourceRange().getBegin(), 8052 diag::err_ovl_no_viable_function_in_call) 8053 << ULE->getName() << Fn->getSourceRange(); 8054 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8055 break; 8056 } 8057 8058 case OR_Ambiguous: 8059 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_ambiguous_call) 8060 << ULE->getName() << Fn->getSourceRange(); 8061 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 8062 break; 8063 8064 case OR_Deleted: 8065 { 8066 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_deleted_call) 8067 << Best->Function->isDeleted() 8068 << ULE->getName() 8069 << getDeletedOrUnavailableSuffix(Best->Function) 8070 << Fn->getSourceRange(); 8071 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8072 } 8073 break; 8074 } 8075 8076 // Overload resolution failed. 8077 return ExprError(); 8078} 8079 8080static bool IsOverloaded(const UnresolvedSetImpl &Functions) { 8081 return Functions.size() > 1 || 8082 (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); 8083} 8084 8085/// \brief Create a unary operation that may resolve to an overloaded 8086/// operator. 8087/// 8088/// \param OpLoc The location of the operator itself (e.g., '*'). 8089/// 8090/// \param OpcIn The UnaryOperator::Opcode that describes this 8091/// operator. 8092/// 8093/// \param Functions The set of non-member functions that will be 8094/// considered by overload resolution. The caller needs to build this 8095/// set based on the context using, e.g., 8096/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8097/// set should not contain any member functions; those will be added 8098/// by CreateOverloadedUnaryOp(). 8099/// 8100/// \param input The input argument. 8101ExprResult 8102Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn, 8103 const UnresolvedSetImpl &Fns, 8104 Expr *Input) { 8105 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 8106 8107 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc); 8108 assert(Op != OO_None && "Invalid opcode for overloaded unary operator"); 8109 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8110 // TODO: provide better source location info. 8111 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8112 8113 if (Input->getObjectKind() == OK_ObjCProperty) { 8114 ExprResult Result = ConvertPropertyForRValue(Input); 8115 if (Result.isInvalid()) 8116 return ExprError(); 8117 Input = Result.take(); 8118 } 8119 8120 Expr *Args[2] = { Input, 0 }; 8121 unsigned NumArgs = 1; 8122 8123 // For post-increment and post-decrement, add the implicit '0' as 8124 // the second argument, so that we know this is a post-increment or 8125 // post-decrement. 8126 if (Opc == UO_PostInc || Opc == UO_PostDec) { 8127 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false); 8128 Args[1] = IntegerLiteral::Create(Context, Zero, Context.IntTy, 8129 SourceLocation()); 8130 NumArgs = 2; 8131 } 8132 8133 if (Input->isTypeDependent()) { 8134 if (Fns.empty()) 8135 return Owned(new (Context) UnaryOperator(Input, 8136 Opc, 8137 Context.DependentTy, 8138 VK_RValue, OK_Ordinary, 8139 OpLoc)); 8140 8141 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8142 UnresolvedLookupExpr *Fn 8143 = UnresolvedLookupExpr::Create(Context, NamingClass, 8144 NestedNameSpecifierLoc(), OpNameInfo, 8145 /*ADL*/ true, IsOverloaded(Fns), 8146 Fns.begin(), Fns.end()); 8147 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8148 &Args[0], NumArgs, 8149 Context.DependentTy, 8150 VK_RValue, 8151 OpLoc)); 8152 } 8153 8154 // Build an empty overload set. 8155 OverloadCandidateSet CandidateSet(OpLoc); 8156 8157 // Add the candidates from the given function set. 8158 AddFunctionCandidates(Fns, &Args[0], NumArgs, CandidateSet, false); 8159 8160 // Add operator candidates that are member functions. 8161 AddMemberOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8162 8163 // Add candidates from ADL. 8164 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8165 Args, NumArgs, 8166 /*ExplicitTemplateArgs*/ 0, 8167 CandidateSet); 8168 8169 // Add builtin operator candidates. 8170 AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8171 8172 // Perform overload resolution. 8173 OverloadCandidateSet::iterator Best; 8174 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8175 case OR_Success: { 8176 // We found a built-in operator or an overloaded operator. 8177 FunctionDecl *FnDecl = Best->Function; 8178 8179 if (FnDecl) { 8180 // We matched an overloaded operator. Build a call to that 8181 // operator. 8182 8183 MarkDeclarationReferenced(OpLoc, FnDecl); 8184 8185 // Convert the arguments. 8186 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8187 CheckMemberOperatorAccess(OpLoc, Args[0], 0, Best->FoundDecl); 8188 8189 ExprResult InputRes = 8190 PerformObjectArgumentInitialization(Input, /*Qualifier=*/0, 8191 Best->FoundDecl, Method); 8192 if (InputRes.isInvalid()) 8193 return ExprError(); 8194 Input = InputRes.take(); 8195 } else { 8196 // Convert the arguments. 8197 ExprResult InputInit 8198 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8199 Context, 8200 FnDecl->getParamDecl(0)), 8201 SourceLocation(), 8202 Input); 8203 if (InputInit.isInvalid()) 8204 return ExprError(); 8205 Input = InputInit.take(); 8206 } 8207 8208 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8209 8210 // Determine the result type. 8211 QualType ResultTy = FnDecl->getResultType(); 8212 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8213 ResultTy = ResultTy.getNonLValueExprType(Context); 8214 8215 // Build the actual expression node. 8216 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl); 8217 if (FnExpr.isInvalid()) 8218 return ExprError(); 8219 8220 Args[0] = Input; 8221 CallExpr *TheCall = 8222 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8223 Args, NumArgs, ResultTy, VK, OpLoc); 8224 8225 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8226 FnDecl)) 8227 return ExprError(); 8228 8229 return MaybeBindToTemporary(TheCall); 8230 } else { 8231 // We matched a built-in operator. Convert the arguments, then 8232 // break out so that we will build the appropriate built-in 8233 // operator node. 8234 ExprResult InputRes = 8235 PerformImplicitConversion(Input, Best->BuiltinTypes.ParamTypes[0], 8236 Best->Conversions[0], AA_Passing); 8237 if (InputRes.isInvalid()) 8238 return ExprError(); 8239 Input = InputRes.take(); 8240 break; 8241 } 8242 } 8243 8244 case OR_No_Viable_Function: 8245 // This is an erroneous use of an operator which can be overloaded by 8246 // a non-member function. Check for non-member operators which were 8247 // defined too late to be candidates. 8248 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args, NumArgs)) 8249 // FIXME: Recover by calling the found function. 8250 return ExprError(); 8251 8252 // No viable function; fall through to handling this as a 8253 // built-in operator, which will produce an error message for us. 8254 break; 8255 8256 case OR_Ambiguous: 8257 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 8258 << UnaryOperator::getOpcodeStr(Opc) 8259 << Input->getType() 8260 << Input->getSourceRange(); 8261 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, 8262 Args, NumArgs, 8263 UnaryOperator::getOpcodeStr(Opc), OpLoc); 8264 return ExprError(); 8265 8266 case OR_Deleted: 8267 Diag(OpLoc, diag::err_ovl_deleted_oper) 8268 << Best->Function->isDeleted() 8269 << UnaryOperator::getOpcodeStr(Opc) 8270 << getDeletedOrUnavailableSuffix(Best->Function) 8271 << Input->getSourceRange(); 8272 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8273 return ExprError(); 8274 } 8275 8276 // Either we found no viable overloaded operator or we matched a 8277 // built-in operator. In either case, fall through to trying to 8278 // build a built-in operation. 8279 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8280} 8281 8282/// \brief Create a binary operation that may resolve to an overloaded 8283/// operator. 8284/// 8285/// \param OpLoc The location of the operator itself (e.g., '+'). 8286/// 8287/// \param OpcIn The BinaryOperator::Opcode that describes this 8288/// operator. 8289/// 8290/// \param Functions The set of non-member functions that will be 8291/// considered by overload resolution. The caller needs to build this 8292/// set based on the context using, e.g., 8293/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8294/// set should not contain any member functions; those will be added 8295/// by CreateOverloadedBinOp(). 8296/// 8297/// \param LHS Left-hand argument. 8298/// \param RHS Right-hand argument. 8299ExprResult 8300Sema::CreateOverloadedBinOp(SourceLocation OpLoc, 8301 unsigned OpcIn, 8302 const UnresolvedSetImpl &Fns, 8303 Expr *LHS, Expr *RHS) { 8304 Expr *Args[2] = { LHS, RHS }; 8305 LHS=RHS=0; //Please use only Args instead of LHS/RHS couple 8306 8307 BinaryOperator::Opcode Opc = static_cast<BinaryOperator::Opcode>(OpcIn); 8308 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc); 8309 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8310 8311 // If either side is type-dependent, create an appropriate dependent 8312 // expression. 8313 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8314 if (Fns.empty()) { 8315 // If there are no functions to store, just build a dependent 8316 // BinaryOperator or CompoundAssignment. 8317 if (Opc <= BO_Assign || Opc > BO_OrAssign) 8318 return Owned(new (Context) BinaryOperator(Args[0], Args[1], Opc, 8319 Context.DependentTy, 8320 VK_RValue, OK_Ordinary, 8321 OpLoc)); 8322 8323 return Owned(new (Context) CompoundAssignOperator(Args[0], Args[1], Opc, 8324 Context.DependentTy, 8325 VK_LValue, 8326 OK_Ordinary, 8327 Context.DependentTy, 8328 Context.DependentTy, 8329 OpLoc)); 8330 } 8331 8332 // FIXME: save results of ADL from here? 8333 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8334 // TODO: provide better source location info in DNLoc component. 8335 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8336 UnresolvedLookupExpr *Fn 8337 = UnresolvedLookupExpr::Create(Context, NamingClass, 8338 NestedNameSpecifierLoc(), OpNameInfo, 8339 /*ADL*/ true, IsOverloaded(Fns), 8340 Fns.begin(), Fns.end()); 8341 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8342 Args, 2, 8343 Context.DependentTy, 8344 VK_RValue, 8345 OpLoc)); 8346 } 8347 8348 // Always do property rvalue conversions on the RHS. 8349 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8350 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8351 if (Result.isInvalid()) 8352 return ExprError(); 8353 Args[1] = Result.take(); 8354 } 8355 8356 // The LHS is more complicated. 8357 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8358 8359 // There's a tension for assignment operators between primitive 8360 // property assignment and the overloaded operators. 8361 if (BinaryOperator::isAssignmentOp(Opc)) { 8362 const ObjCPropertyRefExpr *PRE = LHS->getObjCProperty(); 8363 8364 // Is the property "logically" settable? 8365 bool Settable = (PRE->isExplicitProperty() || 8366 PRE->getImplicitPropertySetter()); 8367 8368 // To avoid gratuitously inventing semantics, use the primitive 8369 // unless it isn't. Thoughts in case we ever really care: 8370 // - If the property isn't logically settable, we have to 8371 // load and hope. 8372 // - If the property is settable and this is simple assignment, 8373 // we really should use the primitive. 8374 // - If the property is settable, then we could try overloading 8375 // on a generic lvalue of the appropriate type; if it works 8376 // out to a builtin candidate, we would do that same operation 8377 // on the property, and otherwise just error. 8378 if (Settable) 8379 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8380 } 8381 8382 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8383 if (Result.isInvalid()) 8384 return ExprError(); 8385 Args[0] = Result.take(); 8386 } 8387 8388 // If this is the assignment operator, we only perform overload resolution 8389 // if the left-hand side is a class or enumeration type. This is actually 8390 // a hack. The standard requires that we do overload resolution between the 8391 // various built-in candidates, but as DR507 points out, this can lead to 8392 // problems. So we do it this way, which pretty much follows what GCC does. 8393 // Note that we go the traditional code path for compound assignment forms. 8394 if (Opc == BO_Assign && !Args[0]->getType()->isOverloadableType()) 8395 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8396 8397 // If this is the .* operator, which is not overloadable, just 8398 // create a built-in binary operator. 8399 if (Opc == BO_PtrMemD) 8400 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8401 8402 // Build an empty overload set. 8403 OverloadCandidateSet CandidateSet(OpLoc); 8404 8405 // Add the candidates from the given function set. 8406 AddFunctionCandidates(Fns, Args, 2, CandidateSet, false); 8407 8408 // Add operator candidates that are member functions. 8409 AddMemberOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8410 8411 // Add candidates from ADL. 8412 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8413 Args, 2, 8414 /*ExplicitTemplateArgs*/ 0, 8415 CandidateSet); 8416 8417 // Add builtin operator candidates. 8418 AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8419 8420 // Perform overload resolution. 8421 OverloadCandidateSet::iterator Best; 8422 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8423 case OR_Success: { 8424 // We found a built-in operator or an overloaded operator. 8425 FunctionDecl *FnDecl = Best->Function; 8426 8427 if (FnDecl) { 8428 // We matched an overloaded operator. Build a call to that 8429 // operator. 8430 8431 MarkDeclarationReferenced(OpLoc, FnDecl); 8432 8433 // Convert the arguments. 8434 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8435 // Best->Access is only meaningful for class members. 8436 CheckMemberOperatorAccess(OpLoc, Args[0], Args[1], Best->FoundDecl); 8437 8438 ExprResult Arg1 = 8439 PerformCopyInitialization( 8440 InitializedEntity::InitializeParameter(Context, 8441 FnDecl->getParamDecl(0)), 8442 SourceLocation(), Owned(Args[1])); 8443 if (Arg1.isInvalid()) 8444 return ExprError(); 8445 8446 ExprResult Arg0 = 8447 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8448 Best->FoundDecl, Method); 8449 if (Arg0.isInvalid()) 8450 return ExprError(); 8451 Args[0] = Arg0.takeAs<Expr>(); 8452 Args[1] = RHS = Arg1.takeAs<Expr>(); 8453 } else { 8454 // Convert the arguments. 8455 ExprResult Arg0 = PerformCopyInitialization( 8456 InitializedEntity::InitializeParameter(Context, 8457 FnDecl->getParamDecl(0)), 8458 SourceLocation(), Owned(Args[0])); 8459 if (Arg0.isInvalid()) 8460 return ExprError(); 8461 8462 ExprResult Arg1 = 8463 PerformCopyInitialization( 8464 InitializedEntity::InitializeParameter(Context, 8465 FnDecl->getParamDecl(1)), 8466 SourceLocation(), Owned(Args[1])); 8467 if (Arg1.isInvalid()) 8468 return ExprError(); 8469 Args[0] = LHS = Arg0.takeAs<Expr>(); 8470 Args[1] = RHS = Arg1.takeAs<Expr>(); 8471 } 8472 8473 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8474 8475 // Determine the result type. 8476 QualType ResultTy = FnDecl->getResultType(); 8477 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8478 ResultTy = ResultTy.getNonLValueExprType(Context); 8479 8480 // Build the actual expression node. 8481 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, OpLoc); 8482 if (FnExpr.isInvalid()) 8483 return ExprError(); 8484 8485 CXXOperatorCallExpr *TheCall = 8486 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8487 Args, 2, ResultTy, VK, OpLoc); 8488 8489 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8490 FnDecl)) 8491 return ExprError(); 8492 8493 return MaybeBindToTemporary(TheCall); 8494 } else { 8495 // We matched a built-in operator. Convert the arguments, then 8496 // break out so that we will build the appropriate built-in 8497 // operator node. 8498 ExprResult ArgsRes0 = 8499 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8500 Best->Conversions[0], AA_Passing); 8501 if (ArgsRes0.isInvalid()) 8502 return ExprError(); 8503 Args[0] = ArgsRes0.take(); 8504 8505 ExprResult ArgsRes1 = 8506 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8507 Best->Conversions[1], AA_Passing); 8508 if (ArgsRes1.isInvalid()) 8509 return ExprError(); 8510 Args[1] = ArgsRes1.take(); 8511 break; 8512 } 8513 } 8514 8515 case OR_No_Viable_Function: { 8516 // C++ [over.match.oper]p9: 8517 // If the operator is the operator , [...] and there are no 8518 // viable functions, then the operator is assumed to be the 8519 // built-in operator and interpreted according to clause 5. 8520 if (Opc == BO_Comma) 8521 break; 8522 8523 // For class as left operand for assignment or compound assigment 8524 // operator do not fall through to handling in built-in, but report that 8525 // no overloaded assignment operator found 8526 ExprResult Result = ExprError(); 8527 if (Args[0]->getType()->isRecordType() && 8528 Opc >= BO_Assign && Opc <= BO_OrAssign) { 8529 Diag(OpLoc, diag::err_ovl_no_viable_oper) 8530 << BinaryOperator::getOpcodeStr(Opc) 8531 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8532 } else { 8533 // This is an erroneous use of an operator which can be overloaded by 8534 // a non-member function. Check for non-member operators which were 8535 // defined too late to be candidates. 8536 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args, 2)) 8537 // FIXME: Recover by calling the found function. 8538 return ExprError(); 8539 8540 // No viable function; try to create a built-in operation, which will 8541 // produce an error. Then, show the non-viable candidates. 8542 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8543 } 8544 assert(Result.isInvalid() && 8545 "C++ binary operator overloading is missing candidates!"); 8546 if (Result.isInvalid()) 8547 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8548 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8549 return move(Result); 8550 } 8551 8552 case OR_Ambiguous: 8553 Diag(OpLoc, diag::err_ovl_ambiguous_oper_binary) 8554 << BinaryOperator::getOpcodeStr(Opc) 8555 << Args[0]->getType() << Args[1]->getType() 8556 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8557 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8558 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8559 return ExprError(); 8560 8561 case OR_Deleted: 8562 Diag(OpLoc, diag::err_ovl_deleted_oper) 8563 << Best->Function->isDeleted() 8564 << BinaryOperator::getOpcodeStr(Opc) 8565 << getDeletedOrUnavailableSuffix(Best->Function) 8566 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8567 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2); 8568 return ExprError(); 8569 } 8570 8571 // We matched a built-in operator; build it. 8572 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8573} 8574 8575ExprResult 8576Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc, 8577 SourceLocation RLoc, 8578 Expr *Base, Expr *Idx) { 8579 Expr *Args[2] = { Base, Idx }; 8580 DeclarationName OpName = 8581 Context.DeclarationNames.getCXXOperatorName(OO_Subscript); 8582 8583 // If either side is type-dependent, create an appropriate dependent 8584 // expression. 8585 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8586 8587 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8588 // CHECKME: no 'operator' keyword? 8589 DeclarationNameInfo OpNameInfo(OpName, LLoc); 8590 OpNameInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc)); 8591 UnresolvedLookupExpr *Fn 8592 = UnresolvedLookupExpr::Create(Context, NamingClass, 8593 NestedNameSpecifierLoc(), OpNameInfo, 8594 /*ADL*/ true, /*Overloaded*/ false, 8595 UnresolvedSetIterator(), 8596 UnresolvedSetIterator()); 8597 // Can't add any actual overloads yet 8598 8599 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, Fn, 8600 Args, 2, 8601 Context.DependentTy, 8602 VK_RValue, 8603 RLoc)); 8604 } 8605 8606 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8607 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8608 if (Result.isInvalid()) 8609 return ExprError(); 8610 Args[0] = Result.take(); 8611 } 8612 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8613 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8614 if (Result.isInvalid()) 8615 return ExprError(); 8616 Args[1] = Result.take(); 8617 } 8618 8619 // Build an empty overload set. 8620 OverloadCandidateSet CandidateSet(LLoc); 8621 8622 // Subscript can only be overloaded as a member function. 8623 8624 // Add operator candidates that are member functions. 8625 AddMemberOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 8626 8627 // Add builtin operator candidates. 8628 AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 8629 8630 // Perform overload resolution. 8631 OverloadCandidateSet::iterator Best; 8632 switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) { 8633 case OR_Success: { 8634 // We found a built-in operator or an overloaded operator. 8635 FunctionDecl *FnDecl = Best->Function; 8636 8637 if (FnDecl) { 8638 // We matched an overloaded operator. Build a call to that 8639 // operator. 8640 8641 MarkDeclarationReferenced(LLoc, FnDecl); 8642 8643 CheckMemberOperatorAccess(LLoc, Args[0], Args[1], Best->FoundDecl); 8644 DiagnoseUseOfDecl(Best->FoundDecl, LLoc); 8645 8646 // Convert the arguments. 8647 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 8648 ExprResult Arg0 = 8649 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8650 Best->FoundDecl, Method); 8651 if (Arg0.isInvalid()) 8652 return ExprError(); 8653 Args[0] = Arg0.take(); 8654 8655 // Convert the arguments. 8656 ExprResult InputInit 8657 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8658 Context, 8659 FnDecl->getParamDecl(0)), 8660 SourceLocation(), 8661 Owned(Args[1])); 8662 if (InputInit.isInvalid()) 8663 return ExprError(); 8664 8665 Args[1] = InputInit.takeAs<Expr>(); 8666 8667 // Determine the result type 8668 QualType ResultTy = FnDecl->getResultType(); 8669 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8670 ResultTy = ResultTy.getNonLValueExprType(Context); 8671 8672 // Build the actual expression node. 8673 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, LLoc); 8674 if (FnExpr.isInvalid()) 8675 return ExprError(); 8676 8677 CXXOperatorCallExpr *TheCall = 8678 new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 8679 FnExpr.take(), Args, 2, 8680 ResultTy, VK, RLoc); 8681 8682 if (CheckCallReturnType(FnDecl->getResultType(), LLoc, TheCall, 8683 FnDecl)) 8684 return ExprError(); 8685 8686 return MaybeBindToTemporary(TheCall); 8687 } else { 8688 // We matched a built-in operator. Convert the arguments, then 8689 // break out so that we will build the appropriate built-in 8690 // operator node. 8691 ExprResult ArgsRes0 = 8692 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8693 Best->Conversions[0], AA_Passing); 8694 if (ArgsRes0.isInvalid()) 8695 return ExprError(); 8696 Args[0] = ArgsRes0.take(); 8697 8698 ExprResult ArgsRes1 = 8699 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8700 Best->Conversions[1], AA_Passing); 8701 if (ArgsRes1.isInvalid()) 8702 return ExprError(); 8703 Args[1] = ArgsRes1.take(); 8704 8705 break; 8706 } 8707 } 8708 8709 case OR_No_Viable_Function: { 8710 if (CandidateSet.empty()) 8711 Diag(LLoc, diag::err_ovl_no_oper) 8712 << Args[0]->getType() << /*subscript*/ 0 8713 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8714 else 8715 Diag(LLoc, diag::err_ovl_no_viable_subscript) 8716 << Args[0]->getType() 8717 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8718 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8719 "[]", LLoc); 8720 return ExprError(); 8721 } 8722 8723 case OR_Ambiguous: 8724 Diag(LLoc, diag::err_ovl_ambiguous_oper_binary) 8725 << "[]" 8726 << Args[0]->getType() << Args[1]->getType() 8727 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8728 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8729 "[]", LLoc); 8730 return ExprError(); 8731 8732 case OR_Deleted: 8733 Diag(LLoc, diag::err_ovl_deleted_oper) 8734 << Best->Function->isDeleted() << "[]" 8735 << getDeletedOrUnavailableSuffix(Best->Function) 8736 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8737 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8738 "[]", LLoc); 8739 return ExprError(); 8740 } 8741 8742 // We matched a built-in operator; build it. 8743 return CreateBuiltinArraySubscriptExpr(Args[0], LLoc, Args[1], RLoc); 8744} 8745 8746/// BuildCallToMemberFunction - Build a call to a member 8747/// function. MemExpr is the expression that refers to the member 8748/// function (and includes the object parameter), Args/NumArgs are the 8749/// arguments to the function call (not including the object 8750/// parameter). The caller needs to validate that the member 8751/// expression refers to a non-static member function or an overloaded 8752/// member function. 8753ExprResult 8754Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE, 8755 SourceLocation LParenLoc, Expr **Args, 8756 unsigned NumArgs, SourceLocation RParenLoc) { 8757 assert(MemExprE->getType() == Context.BoundMemberTy || 8758 MemExprE->getType() == Context.OverloadTy); 8759 8760 // Dig out the member expression. This holds both the object 8761 // argument and the member function we're referring to. 8762 Expr *NakedMemExpr = MemExprE->IgnoreParens(); 8763 8764 // Determine whether this is a call to a pointer-to-member function. 8765 if (BinaryOperator *op = dyn_cast<BinaryOperator>(NakedMemExpr)) { 8766 assert(op->getType() == Context.BoundMemberTy); 8767 assert(op->getOpcode() == BO_PtrMemD || op->getOpcode() == BO_PtrMemI); 8768 8769 QualType fnType = 8770 op->getRHS()->getType()->castAs<MemberPointerType>()->getPointeeType(); 8771 8772 const FunctionProtoType *proto = fnType->castAs<FunctionProtoType>(); 8773 QualType resultType = proto->getCallResultType(Context); 8774 ExprValueKind valueKind = Expr::getValueKindForType(proto->getResultType()); 8775 8776 // Check that the object type isn't more qualified than the 8777 // member function we're calling. 8778 Qualifiers funcQuals = Qualifiers::fromCVRMask(proto->getTypeQuals()); 8779 8780 QualType objectType = op->getLHS()->getType(); 8781 if (op->getOpcode() == BO_PtrMemI) 8782 objectType = objectType->castAs<PointerType>()->getPointeeType(); 8783 Qualifiers objectQuals = objectType.getQualifiers(); 8784 8785 Qualifiers difference = objectQuals - funcQuals; 8786 difference.removeObjCGCAttr(); 8787 difference.removeAddressSpace(); 8788 if (difference) { 8789 std::string qualsString = difference.getAsString(); 8790 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals) 8791 << fnType.getUnqualifiedType() 8792 << qualsString 8793 << (qualsString.find(' ') == std::string::npos ? 1 : 2); 8794 } 8795 8796 CXXMemberCallExpr *call 8797 = new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 8798 resultType, valueKind, RParenLoc); 8799 8800 if (CheckCallReturnType(proto->getResultType(), 8801 op->getRHS()->getSourceRange().getBegin(), 8802 call, 0)) 8803 return ExprError(); 8804 8805 if (ConvertArgumentsForCall(call, op, 0, proto, Args, NumArgs, RParenLoc)) 8806 return ExprError(); 8807 8808 return MaybeBindToTemporary(call); 8809 } 8810 8811 MemberExpr *MemExpr; 8812 CXXMethodDecl *Method = 0; 8813 DeclAccessPair FoundDecl = DeclAccessPair::make(0, AS_public); 8814 NestedNameSpecifier *Qualifier = 0; 8815 if (isa<MemberExpr>(NakedMemExpr)) { 8816 MemExpr = cast<MemberExpr>(NakedMemExpr); 8817 Method = cast<CXXMethodDecl>(MemExpr->getMemberDecl()); 8818 FoundDecl = MemExpr->getFoundDecl(); 8819 Qualifier = MemExpr->getQualifier(); 8820 } else { 8821 UnresolvedMemberExpr *UnresExpr = cast<UnresolvedMemberExpr>(NakedMemExpr); 8822 Qualifier = UnresExpr->getQualifier(); 8823 8824 QualType ObjectType = UnresExpr->getBaseType(); 8825 Expr::Classification ObjectClassification 8826 = UnresExpr->isArrow()? Expr::Classification::makeSimpleLValue() 8827 : UnresExpr->getBase()->Classify(Context); 8828 8829 // Add overload candidates 8830 OverloadCandidateSet CandidateSet(UnresExpr->getMemberLoc()); 8831 8832 // FIXME: avoid copy. 8833 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 8834 if (UnresExpr->hasExplicitTemplateArgs()) { 8835 UnresExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 8836 TemplateArgs = &TemplateArgsBuffer; 8837 } 8838 8839 for (UnresolvedMemberExpr::decls_iterator I = UnresExpr->decls_begin(), 8840 E = UnresExpr->decls_end(); I != E; ++I) { 8841 8842 NamedDecl *Func = *I; 8843 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(Func->getDeclContext()); 8844 if (isa<UsingShadowDecl>(Func)) 8845 Func = cast<UsingShadowDecl>(Func)->getTargetDecl(); 8846 8847 8848 // Microsoft supports direct constructor calls. 8849 if (getLangOptions().Microsoft && isa<CXXConstructorDecl>(Func)) { 8850 AddOverloadCandidate(cast<CXXConstructorDecl>(Func), I.getPair(), Args, NumArgs, 8851 CandidateSet); 8852 } else if ((Method = dyn_cast<CXXMethodDecl>(Func))) { 8853 // If explicit template arguments were provided, we can't call a 8854 // non-template member function. 8855 if (TemplateArgs) 8856 continue; 8857 8858 AddMethodCandidate(Method, I.getPair(), ActingDC, ObjectType, 8859 ObjectClassification, 8860 Args, NumArgs, CandidateSet, 8861 /*SuppressUserConversions=*/false); 8862 } else { 8863 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(Func), 8864 I.getPair(), ActingDC, TemplateArgs, 8865 ObjectType, ObjectClassification, 8866 Args, NumArgs, CandidateSet, 8867 /*SuppressUsedConversions=*/false); 8868 } 8869 } 8870 8871 DeclarationName DeclName = UnresExpr->getMemberName(); 8872 8873 OverloadCandidateSet::iterator Best; 8874 switch (CandidateSet.BestViableFunction(*this, UnresExpr->getLocStart(), 8875 Best)) { 8876 case OR_Success: 8877 Method = cast<CXXMethodDecl>(Best->Function); 8878 MarkDeclarationReferenced(UnresExpr->getMemberLoc(), Method); 8879 FoundDecl = Best->FoundDecl; 8880 CheckUnresolvedMemberAccess(UnresExpr, Best->FoundDecl); 8881 DiagnoseUseOfDecl(Best->FoundDecl, UnresExpr->getNameLoc()); 8882 break; 8883 8884 case OR_No_Viable_Function: 8885 Diag(UnresExpr->getMemberLoc(), 8886 diag::err_ovl_no_viable_member_function_in_call) 8887 << DeclName << MemExprE->getSourceRange(); 8888 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8889 // FIXME: Leaking incoming expressions! 8890 return ExprError(); 8891 8892 case OR_Ambiguous: 8893 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_ambiguous_member_call) 8894 << DeclName << MemExprE->getSourceRange(); 8895 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8896 // FIXME: Leaking incoming expressions! 8897 return ExprError(); 8898 8899 case OR_Deleted: 8900 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_deleted_member_call) 8901 << Best->Function->isDeleted() 8902 << DeclName 8903 << getDeletedOrUnavailableSuffix(Best->Function) 8904 << MemExprE->getSourceRange(); 8905 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8906 // FIXME: Leaking incoming expressions! 8907 return ExprError(); 8908 } 8909 8910 MemExprE = FixOverloadedFunctionReference(MemExprE, FoundDecl, Method); 8911 8912 // If overload resolution picked a static member, build a 8913 // non-member call based on that function. 8914 if (Method->isStatic()) { 8915 return BuildResolvedCallExpr(MemExprE, Method, LParenLoc, 8916 Args, NumArgs, RParenLoc); 8917 } 8918 8919 MemExpr = cast<MemberExpr>(MemExprE->IgnoreParens()); 8920 } 8921 8922 QualType ResultType = Method->getResultType(); 8923 ExprValueKind VK = Expr::getValueKindForType(ResultType); 8924 ResultType = ResultType.getNonLValueExprType(Context); 8925 8926 assert(Method && "Member call to something that isn't a method?"); 8927 CXXMemberCallExpr *TheCall = 8928 new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 8929 ResultType, VK, RParenLoc); 8930 8931 // Check for a valid return type. 8932 if (CheckCallReturnType(Method->getResultType(), MemExpr->getMemberLoc(), 8933 TheCall, Method)) 8934 return ExprError(); 8935 8936 // Convert the object argument (for a non-static member function call). 8937 // We only need to do this if there was actually an overload; otherwise 8938 // it was done at lookup. 8939 if (!Method->isStatic()) { 8940 ExprResult ObjectArg = 8941 PerformObjectArgumentInitialization(MemExpr->getBase(), Qualifier, 8942 FoundDecl, Method); 8943 if (ObjectArg.isInvalid()) 8944 return ExprError(); 8945 MemExpr->setBase(ObjectArg.take()); 8946 } 8947 8948 // Convert the rest of the arguments 8949 const FunctionProtoType *Proto = 8950 Method->getType()->getAs<FunctionProtoType>(); 8951 if (ConvertArgumentsForCall(TheCall, MemExpr, Method, Proto, Args, NumArgs, 8952 RParenLoc)) 8953 return ExprError(); 8954 8955 if (CheckFunctionCall(Method, TheCall)) 8956 return ExprError(); 8957 8958 if ((isa<CXXConstructorDecl>(CurContext) || 8959 isa<CXXDestructorDecl>(CurContext)) && 8960 TheCall->getMethodDecl()->isPure()) { 8961 const CXXMethodDecl *MD = TheCall->getMethodDecl(); 8962 8963 if (isa<CXXThisExpr>(MemExpr->getBase()->IgnoreParenCasts())) 8964 Diag(MemExpr->getLocStart(), 8965 diag::warn_call_to_pure_virtual_member_function_from_ctor_dtor) 8966 << MD->getDeclName() << isa<CXXDestructorDecl>(CurContext) 8967 << MD->getParent()->getDeclName(); 8968 8969 Diag(MD->getLocStart(), diag::note_previous_decl) << MD->getDeclName(); 8970 } 8971 return MaybeBindToTemporary(TheCall); 8972} 8973 8974/// BuildCallToObjectOfClassType - Build a call to an object of class 8975/// type (C++ [over.call.object]), which can end up invoking an 8976/// overloaded function call operator (@c operator()) or performing a 8977/// user-defined conversion on the object argument. 8978ExprResult 8979Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj, 8980 SourceLocation LParenLoc, 8981 Expr **Args, unsigned NumArgs, 8982 SourceLocation RParenLoc) { 8983 ExprResult Object = Owned(Obj); 8984 if (Object.get()->getObjectKind() == OK_ObjCProperty) { 8985 Object = ConvertPropertyForRValue(Object.take()); 8986 if (Object.isInvalid()) 8987 return ExprError(); 8988 } 8989 8990 assert(Object.get()->getType()->isRecordType() && "Requires object type argument"); 8991 const RecordType *Record = Object.get()->getType()->getAs<RecordType>(); 8992 8993 // C++ [over.call.object]p1: 8994 // If the primary-expression E in the function call syntax 8995 // evaluates to a class object of type "cv T", then the set of 8996 // candidate functions includes at least the function call 8997 // operators of T. The function call operators of T are obtained by 8998 // ordinary lookup of the name operator() in the context of 8999 // (E).operator(). 9000 OverloadCandidateSet CandidateSet(LParenLoc); 9001 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call); 9002 9003 if (RequireCompleteType(LParenLoc, Object.get()->getType(), 9004 PDiag(diag::err_incomplete_object_call) 9005 << Object.get()->getSourceRange())) 9006 return true; 9007 9008 LookupResult R(*this, OpName, LParenLoc, LookupOrdinaryName); 9009 LookupQualifiedName(R, Record->getDecl()); 9010 R.suppressDiagnostics(); 9011 9012 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9013 Oper != OperEnd; ++Oper) { 9014 AddMethodCandidate(Oper.getPair(), Object.get()->getType(), 9015 Object.get()->Classify(Context), Args, NumArgs, CandidateSet, 9016 /*SuppressUserConversions=*/ false); 9017 } 9018 9019 // C++ [over.call.object]p2: 9020 // In addition, for each conversion function declared in T of the 9021 // form 9022 // 9023 // operator conversion-type-id () cv-qualifier; 9024 // 9025 // where cv-qualifier is the same cv-qualification as, or a 9026 // greater cv-qualification than, cv, and where conversion-type-id 9027 // denotes the type "pointer to function of (P1,...,Pn) returning 9028 // R", or the type "reference to pointer to function of 9029 // (P1,...,Pn) returning R", or the type "reference to function 9030 // of (P1,...,Pn) returning R", a surrogate call function [...] 9031 // is also considered as a candidate function. Similarly, 9032 // surrogate call functions are added to the set of candidate 9033 // functions for each conversion function declared in an 9034 // accessible base class provided the function is not hidden 9035 // within T by another intervening declaration. 9036 const UnresolvedSetImpl *Conversions 9037 = cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions(); 9038 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 9039 E = Conversions->end(); I != E; ++I) { 9040 NamedDecl *D = *I; 9041 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 9042 if (isa<UsingShadowDecl>(D)) 9043 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 9044 9045 // Skip over templated conversion functions; they aren't 9046 // surrogates. 9047 if (isa<FunctionTemplateDecl>(D)) 9048 continue; 9049 9050 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 9051 9052 // Strip the reference type (if any) and then the pointer type (if 9053 // any) to get down to what might be a function type. 9054 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 9055 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 9056 ConvType = ConvPtrType->getPointeeType(); 9057 9058 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>()) 9059 AddSurrogateCandidate(Conv, I.getPair(), ActingContext, Proto, 9060 Object.get(), Args, NumArgs, CandidateSet); 9061 } 9062 9063 // Perform overload resolution. 9064 OverloadCandidateSet::iterator Best; 9065 switch (CandidateSet.BestViableFunction(*this, Object.get()->getLocStart(), 9066 Best)) { 9067 case OR_Success: 9068 // Overload resolution succeeded; we'll build the appropriate call 9069 // below. 9070 break; 9071 9072 case OR_No_Viable_Function: 9073 if (CandidateSet.empty()) 9074 Diag(Object.get()->getSourceRange().getBegin(), diag::err_ovl_no_oper) 9075 << Object.get()->getType() << /*call*/ 1 9076 << Object.get()->getSourceRange(); 9077 else 9078 Diag(Object.get()->getSourceRange().getBegin(), 9079 diag::err_ovl_no_viable_object_call) 9080 << Object.get()->getType() << Object.get()->getSourceRange(); 9081 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9082 break; 9083 9084 case OR_Ambiguous: 9085 Diag(Object.get()->getSourceRange().getBegin(), 9086 diag::err_ovl_ambiguous_object_call) 9087 << Object.get()->getType() << Object.get()->getSourceRange(); 9088 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 9089 break; 9090 9091 case OR_Deleted: 9092 Diag(Object.get()->getSourceRange().getBegin(), 9093 diag::err_ovl_deleted_object_call) 9094 << Best->Function->isDeleted() 9095 << Object.get()->getType() 9096 << getDeletedOrUnavailableSuffix(Best->Function) 9097 << Object.get()->getSourceRange(); 9098 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9099 break; 9100 } 9101 9102 if (Best == CandidateSet.end()) 9103 return true; 9104 9105 if (Best->Function == 0) { 9106 // Since there is no function declaration, this is one of the 9107 // surrogate candidates. Dig out the conversion function. 9108 CXXConversionDecl *Conv 9109 = cast<CXXConversionDecl>( 9110 Best->Conversions[0].UserDefined.ConversionFunction); 9111 9112 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 9113 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 9114 9115 // We selected one of the surrogate functions that converts the 9116 // object parameter to a function pointer. Perform the conversion 9117 // on the object argument, then let ActOnCallExpr finish the job. 9118 9119 // Create an implicit member expr to refer to the conversion operator. 9120 // and then call it. 9121 ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl, Conv); 9122 if (Call.isInvalid()) 9123 return ExprError(); 9124 9125 return ActOnCallExpr(S, Call.get(), LParenLoc, MultiExprArg(Args, NumArgs), 9126 RParenLoc); 9127 } 9128 9129 MarkDeclarationReferenced(LParenLoc, Best->Function); 9130 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 9131 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 9132 9133 // We found an overloaded operator(). Build a CXXOperatorCallExpr 9134 // that calls this method, using Object for the implicit object 9135 // parameter and passing along the remaining arguments. 9136 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9137 const FunctionProtoType *Proto = 9138 Method->getType()->getAs<FunctionProtoType>(); 9139 9140 unsigned NumArgsInProto = Proto->getNumArgs(); 9141 unsigned NumArgsToCheck = NumArgs; 9142 9143 // Build the full argument list for the method call (the 9144 // implicit object parameter is placed at the beginning of the 9145 // list). 9146 Expr **MethodArgs; 9147 if (NumArgs < NumArgsInProto) { 9148 NumArgsToCheck = NumArgsInProto; 9149 MethodArgs = new Expr*[NumArgsInProto + 1]; 9150 } else { 9151 MethodArgs = new Expr*[NumArgs + 1]; 9152 } 9153 MethodArgs[0] = Object.get(); 9154 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 9155 MethodArgs[ArgIdx + 1] = Args[ArgIdx]; 9156 9157 ExprResult NewFn = CreateFunctionRefExpr(*this, Method); 9158 if (NewFn.isInvalid()) 9159 return true; 9160 9161 // Once we've built TheCall, all of the expressions are properly 9162 // owned. 9163 QualType ResultTy = Method->getResultType(); 9164 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9165 ResultTy = ResultTy.getNonLValueExprType(Context); 9166 9167 CXXOperatorCallExpr *TheCall = 9168 new (Context) CXXOperatorCallExpr(Context, OO_Call, NewFn.take(), 9169 MethodArgs, NumArgs + 1, 9170 ResultTy, VK, RParenLoc); 9171 delete [] MethodArgs; 9172 9173 if (CheckCallReturnType(Method->getResultType(), LParenLoc, TheCall, 9174 Method)) 9175 return true; 9176 9177 // We may have default arguments. If so, we need to allocate more 9178 // slots in the call for them. 9179 if (NumArgs < NumArgsInProto) 9180 TheCall->setNumArgs(Context, NumArgsInProto + 1); 9181 else if (NumArgs > NumArgsInProto) 9182 NumArgsToCheck = NumArgsInProto; 9183 9184 bool IsError = false; 9185 9186 // Initialize the implicit object parameter. 9187 ExprResult ObjRes = 9188 PerformObjectArgumentInitialization(Object.get(), /*Qualifier=*/0, 9189 Best->FoundDecl, Method); 9190 if (ObjRes.isInvalid()) 9191 IsError = true; 9192 else 9193 Object = move(ObjRes); 9194 TheCall->setArg(0, Object.take()); 9195 9196 // Check the argument types. 9197 for (unsigned i = 0; i != NumArgsToCheck; i++) { 9198 Expr *Arg; 9199 if (i < NumArgs) { 9200 Arg = Args[i]; 9201 9202 // Pass the argument. 9203 9204 ExprResult InputInit 9205 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 9206 Context, 9207 Method->getParamDecl(i)), 9208 SourceLocation(), Arg); 9209 9210 IsError |= InputInit.isInvalid(); 9211 Arg = InputInit.takeAs<Expr>(); 9212 } else { 9213 ExprResult DefArg 9214 = BuildCXXDefaultArgExpr(LParenLoc, Method, Method->getParamDecl(i)); 9215 if (DefArg.isInvalid()) { 9216 IsError = true; 9217 break; 9218 } 9219 9220 Arg = DefArg.takeAs<Expr>(); 9221 } 9222 9223 TheCall->setArg(i + 1, Arg); 9224 } 9225 9226 // If this is a variadic call, handle args passed through "...". 9227 if (Proto->isVariadic()) { 9228 // Promote the arguments (C99 6.5.2.2p7). 9229 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 9230 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0); 9231 IsError |= Arg.isInvalid(); 9232 TheCall->setArg(i + 1, Arg.take()); 9233 } 9234 } 9235 9236 if (IsError) return true; 9237 9238 if (CheckFunctionCall(Method, TheCall)) 9239 return true; 9240 9241 return MaybeBindToTemporary(TheCall); 9242} 9243 9244/// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator-> 9245/// (if one exists), where @c Base is an expression of class type and 9246/// @c Member is the name of the member we're trying to find. 9247ExprResult 9248Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) { 9249 assert(Base->getType()->isRecordType() && 9250 "left-hand side must have class type"); 9251 9252 if (Base->getObjectKind() == OK_ObjCProperty) { 9253 ExprResult Result = ConvertPropertyForRValue(Base); 9254 if (Result.isInvalid()) 9255 return ExprError(); 9256 Base = Result.take(); 9257 } 9258 9259 SourceLocation Loc = Base->getExprLoc(); 9260 9261 // C++ [over.ref]p1: 9262 // 9263 // [...] An expression x->m is interpreted as (x.operator->())->m 9264 // for a class object x of type T if T::operator->() exists and if 9265 // the operator is selected as the best match function by the 9266 // overload resolution mechanism (13.3). 9267 DeclarationName OpName = 9268 Context.DeclarationNames.getCXXOperatorName(OO_Arrow); 9269 OverloadCandidateSet CandidateSet(Loc); 9270 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>(); 9271 9272 if (RequireCompleteType(Loc, Base->getType(), 9273 PDiag(diag::err_typecheck_incomplete_tag) 9274 << Base->getSourceRange())) 9275 return ExprError(); 9276 9277 LookupResult R(*this, OpName, OpLoc, LookupOrdinaryName); 9278 LookupQualifiedName(R, BaseRecord->getDecl()); 9279 R.suppressDiagnostics(); 9280 9281 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9282 Oper != OperEnd; ++Oper) { 9283 AddMethodCandidate(Oper.getPair(), Base->getType(), Base->Classify(Context), 9284 0, 0, CandidateSet, /*SuppressUserConversions=*/false); 9285 } 9286 9287 // Perform overload resolution. 9288 OverloadCandidateSet::iterator Best; 9289 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 9290 case OR_Success: 9291 // Overload resolution succeeded; we'll build the call below. 9292 break; 9293 9294 case OR_No_Viable_Function: 9295 if (CandidateSet.empty()) 9296 Diag(OpLoc, diag::err_typecheck_member_reference_arrow) 9297 << Base->getType() << Base->getSourceRange(); 9298 else 9299 Diag(OpLoc, diag::err_ovl_no_viable_oper) 9300 << "operator->" << Base->getSourceRange(); 9301 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9302 return ExprError(); 9303 9304 case OR_Ambiguous: 9305 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 9306 << "->" << Base->getType() << Base->getSourceRange(); 9307 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, &Base, 1); 9308 return ExprError(); 9309 9310 case OR_Deleted: 9311 Diag(OpLoc, diag::err_ovl_deleted_oper) 9312 << Best->Function->isDeleted() 9313 << "->" 9314 << getDeletedOrUnavailableSuffix(Best->Function) 9315 << Base->getSourceRange(); 9316 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9317 return ExprError(); 9318 } 9319 9320 MarkDeclarationReferenced(OpLoc, Best->Function); 9321 CheckMemberOperatorAccess(OpLoc, Base, 0, Best->FoundDecl); 9322 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 9323 9324 // Convert the object parameter. 9325 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9326 ExprResult BaseResult = 9327 PerformObjectArgumentInitialization(Base, /*Qualifier=*/0, 9328 Best->FoundDecl, Method); 9329 if (BaseResult.isInvalid()) 9330 return ExprError(); 9331 Base = BaseResult.take(); 9332 9333 // Build the operator call. 9334 ExprResult FnExpr = CreateFunctionRefExpr(*this, Method); 9335 if (FnExpr.isInvalid()) 9336 return ExprError(); 9337 9338 QualType ResultTy = Method->getResultType(); 9339 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9340 ResultTy = ResultTy.getNonLValueExprType(Context); 9341 CXXOperatorCallExpr *TheCall = 9342 new (Context) CXXOperatorCallExpr(Context, OO_Arrow, FnExpr.take(), 9343 &Base, 1, ResultTy, VK, OpLoc); 9344 9345 if (CheckCallReturnType(Method->getResultType(), OpLoc, TheCall, 9346 Method)) 9347 return ExprError(); 9348 9349 return MaybeBindToTemporary(TheCall); 9350} 9351 9352/// FixOverloadedFunctionReference - E is an expression that refers to 9353/// a C++ overloaded function (possibly with some parentheses and 9354/// perhaps a '&' around it). We have resolved the overloaded function 9355/// to the function declaration Fn, so patch up the expression E to 9356/// refer (possibly indirectly) to Fn. Returns the new expr. 9357Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found, 9358 FunctionDecl *Fn) { 9359 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 9360 Expr *SubExpr = FixOverloadedFunctionReference(PE->getSubExpr(), 9361 Found, Fn); 9362 if (SubExpr == PE->getSubExpr()) 9363 return PE; 9364 9365 return new (Context) ParenExpr(PE->getLParen(), PE->getRParen(), SubExpr); 9366 } 9367 9368 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 9369 Expr *SubExpr = FixOverloadedFunctionReference(ICE->getSubExpr(), 9370 Found, Fn); 9371 assert(Context.hasSameType(ICE->getSubExpr()->getType(), 9372 SubExpr->getType()) && 9373 "Implicit cast type cannot be determined from overload"); 9374 assert(ICE->path_empty() && "fixing up hierarchy conversion?"); 9375 if (SubExpr == ICE->getSubExpr()) 9376 return ICE; 9377 9378 return ImplicitCastExpr::Create(Context, ICE->getType(), 9379 ICE->getCastKind(), 9380 SubExpr, 0, 9381 ICE->getValueKind()); 9382 } 9383 9384 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) { 9385 assert(UnOp->getOpcode() == UO_AddrOf && 9386 "Can only take the address of an overloaded function"); 9387 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 9388 if (Method->isStatic()) { 9389 // Do nothing: static member functions aren't any different 9390 // from non-member functions. 9391 } else { 9392 // Fix the sub expression, which really has to be an 9393 // UnresolvedLookupExpr holding an overloaded member function 9394 // or template. 9395 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9396 Found, Fn); 9397 if (SubExpr == UnOp->getSubExpr()) 9398 return UnOp; 9399 9400 assert(isa<DeclRefExpr>(SubExpr) 9401 && "fixed to something other than a decl ref"); 9402 assert(cast<DeclRefExpr>(SubExpr)->getQualifier() 9403 && "fixed to a member ref with no nested name qualifier"); 9404 9405 // We have taken the address of a pointer to member 9406 // function. Perform the computation here so that we get the 9407 // appropriate pointer to member type. 9408 QualType ClassType 9409 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 9410 QualType MemPtrType 9411 = Context.getMemberPointerType(Fn->getType(), ClassType.getTypePtr()); 9412 9413 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType, 9414 VK_RValue, OK_Ordinary, 9415 UnOp->getOperatorLoc()); 9416 } 9417 } 9418 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9419 Found, Fn); 9420 if (SubExpr == UnOp->getSubExpr()) 9421 return UnOp; 9422 9423 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, 9424 Context.getPointerType(SubExpr->getType()), 9425 VK_RValue, OK_Ordinary, 9426 UnOp->getOperatorLoc()); 9427 } 9428 9429 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 9430 // FIXME: avoid copy. 9431 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9432 if (ULE->hasExplicitTemplateArgs()) { 9433 ULE->copyTemplateArgumentsInto(TemplateArgsBuffer); 9434 TemplateArgs = &TemplateArgsBuffer; 9435 } 9436 9437 return DeclRefExpr::Create(Context, 9438 ULE->getQualifierLoc(), 9439 Fn, 9440 ULE->getNameLoc(), 9441 Fn->getType(), 9442 VK_LValue, 9443 Found.getDecl(), 9444 TemplateArgs); 9445 } 9446 9447 if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) { 9448 // FIXME: avoid copy. 9449 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9450 if (MemExpr->hasExplicitTemplateArgs()) { 9451 MemExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 9452 TemplateArgs = &TemplateArgsBuffer; 9453 } 9454 9455 Expr *Base; 9456 9457 // If we're filling in a static method where we used to have an 9458 // implicit member access, rewrite to a simple decl ref. 9459 if (MemExpr->isImplicitAccess()) { 9460 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9461 return DeclRefExpr::Create(Context, 9462 MemExpr->getQualifierLoc(), 9463 Fn, 9464 MemExpr->getMemberLoc(), 9465 Fn->getType(), 9466 VK_LValue, 9467 Found.getDecl(), 9468 TemplateArgs); 9469 } else { 9470 SourceLocation Loc = MemExpr->getMemberLoc(); 9471 if (MemExpr->getQualifier()) 9472 Loc = MemExpr->getQualifierLoc().getBeginLoc(); 9473 Base = new (Context) CXXThisExpr(Loc, 9474 MemExpr->getBaseType(), 9475 /*isImplicit=*/true); 9476 } 9477 } else 9478 Base = MemExpr->getBase(); 9479 9480 ExprValueKind valueKind; 9481 QualType type; 9482 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9483 valueKind = VK_LValue; 9484 type = Fn->getType(); 9485 } else { 9486 valueKind = VK_RValue; 9487 type = Context.BoundMemberTy; 9488 } 9489 9490 return MemberExpr::Create(Context, Base, 9491 MemExpr->isArrow(), 9492 MemExpr->getQualifierLoc(), 9493 Fn, 9494 Found, 9495 MemExpr->getMemberNameInfo(), 9496 TemplateArgs, 9497 type, valueKind, OK_Ordinary); 9498 } 9499 9500 llvm_unreachable("Invalid reference to overloaded function"); 9501 return E; 9502} 9503 9504ExprResult Sema::FixOverloadedFunctionReference(ExprResult E, 9505 DeclAccessPair Found, 9506 FunctionDecl *Fn) { 9507 return Owned(FixOverloadedFunctionReference((Expr *)E.get(), Found, Fn)); 9508} 9509 9510} // end namespace clang 9511