SemaOverload.cpp revision 6efd4c55a1a481d92966a91141c03e8145234cf6
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, bool HadMultipleCandidates, 41 SourceLocation Loc = SourceLocation(), 42 const DeclarationNameLoc &LocInfo = DeclarationNameLoc()){ 43 DeclRefExpr *DRE = new (S.Context) DeclRefExpr(Fn, Fn->getType(), 44 VK_LValue, Loc, LocInfo); 45 if (HadMultipleCandidates) 46 DRE->setHadMultipleCandidates(true); 47 ExprResult E = S.Owned(DRE); 48 E = S.DefaultFunctionArrayConversion(E.take()); 49 if (E.isInvalid()) 50 return ExprError(); 51 return move(E); 52} 53 54static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 55 bool InOverloadResolution, 56 StandardConversionSequence &SCS, 57 bool CStyle, 58 bool AllowObjCWritebackConversion); 59 60static bool IsTransparentUnionStandardConversion(Sema &S, Expr* From, 61 QualType &ToType, 62 bool InOverloadResolution, 63 StandardConversionSequence &SCS, 64 bool CStyle); 65static OverloadingResult 66IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 67 UserDefinedConversionSequence& User, 68 OverloadCandidateSet& Conversions, 69 bool AllowExplicit); 70 71 72static ImplicitConversionSequence::CompareKind 73CompareStandardConversionSequences(Sema &S, 74 const StandardConversionSequence& SCS1, 75 const StandardConversionSequence& SCS2); 76 77static ImplicitConversionSequence::CompareKind 78CompareQualificationConversions(Sema &S, 79 const StandardConversionSequence& SCS1, 80 const StandardConversionSequence& SCS2); 81 82static ImplicitConversionSequence::CompareKind 83CompareDerivedToBaseConversions(Sema &S, 84 const StandardConversionSequence& SCS1, 85 const StandardConversionSequence& SCS2); 86 87 88 89/// GetConversionCategory - Retrieve the implicit conversion 90/// category corresponding to the given implicit conversion kind. 91ImplicitConversionCategory 92GetConversionCategory(ImplicitConversionKind Kind) { 93 static const ImplicitConversionCategory 94 Category[(int)ICK_Num_Conversion_Kinds] = { 95 ICC_Identity, 96 ICC_Lvalue_Transformation, 97 ICC_Lvalue_Transformation, 98 ICC_Lvalue_Transformation, 99 ICC_Identity, 100 ICC_Qualification_Adjustment, 101 ICC_Promotion, 102 ICC_Promotion, 103 ICC_Promotion, 104 ICC_Conversion, 105 ICC_Conversion, 106 ICC_Conversion, 107 ICC_Conversion, 108 ICC_Conversion, 109 ICC_Conversion, 110 ICC_Conversion, 111 ICC_Conversion, 112 ICC_Conversion, 113 ICC_Conversion, 114 ICC_Conversion, 115 ICC_Conversion, 116 ICC_Conversion 117 }; 118 return Category[(int)Kind]; 119} 120 121/// GetConversionRank - Retrieve the implicit conversion rank 122/// corresponding to the given implicit conversion kind. 123ImplicitConversionRank GetConversionRank(ImplicitConversionKind Kind) { 124 static const ImplicitConversionRank 125 Rank[(int)ICK_Num_Conversion_Kinds] = { 126 ICR_Exact_Match, 127 ICR_Exact_Match, 128 ICR_Exact_Match, 129 ICR_Exact_Match, 130 ICR_Exact_Match, 131 ICR_Exact_Match, 132 ICR_Promotion, 133 ICR_Promotion, 134 ICR_Promotion, 135 ICR_Conversion, 136 ICR_Conversion, 137 ICR_Conversion, 138 ICR_Conversion, 139 ICR_Conversion, 140 ICR_Conversion, 141 ICR_Conversion, 142 ICR_Conversion, 143 ICR_Conversion, 144 ICR_Conversion, 145 ICR_Conversion, 146 ICR_Complex_Real_Conversion, 147 ICR_Conversion, 148 ICR_Conversion, 149 ICR_Writeback_Conversion 150 }; 151 return Rank[(int)Kind]; 152} 153 154/// GetImplicitConversionName - Return the name of this kind of 155/// implicit conversion. 156const char* GetImplicitConversionName(ImplicitConversionKind Kind) { 157 static const char* const Name[(int)ICK_Num_Conversion_Kinds] = { 158 "No conversion", 159 "Lvalue-to-rvalue", 160 "Array-to-pointer", 161 "Function-to-pointer", 162 "Noreturn adjustment", 163 "Qualification", 164 "Integral promotion", 165 "Floating point promotion", 166 "Complex promotion", 167 "Integral conversion", 168 "Floating conversion", 169 "Complex conversion", 170 "Floating-integral conversion", 171 "Pointer conversion", 172 "Pointer-to-member conversion", 173 "Boolean conversion", 174 "Compatible-types conversion", 175 "Derived-to-base conversion", 176 "Vector conversion", 177 "Vector splat", 178 "Complex-real conversion", 179 "Block Pointer conversion", 180 "Transparent Union Conversion" 181 "Writeback conversion" 182 }; 183 return Name[Kind]; 184} 185 186/// StandardConversionSequence - Set the standard conversion 187/// sequence to the identity conversion. 188void StandardConversionSequence::setAsIdentityConversion() { 189 First = ICK_Identity; 190 Second = ICK_Identity; 191 Third = ICK_Identity; 192 DeprecatedStringLiteralToCharPtr = false; 193 QualificationIncludesObjCLifetime = false; 194 ReferenceBinding = false; 195 DirectBinding = false; 196 IsLvalueReference = true; 197 BindsToFunctionLvalue = false; 198 BindsToRvalue = false; 199 BindsImplicitObjectArgumentWithoutRefQualifier = false; 200 ObjCLifetimeConversionBinding = false; 201 CopyConstructor = 0; 202} 203 204/// getRank - Retrieve the rank of this standard conversion sequence 205/// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the 206/// implicit conversions. 207ImplicitConversionRank StandardConversionSequence::getRank() const { 208 ImplicitConversionRank Rank = ICR_Exact_Match; 209 if (GetConversionRank(First) > Rank) 210 Rank = GetConversionRank(First); 211 if (GetConversionRank(Second) > Rank) 212 Rank = GetConversionRank(Second); 213 if (GetConversionRank(Third) > Rank) 214 Rank = GetConversionRank(Third); 215 return Rank; 216} 217 218/// isPointerConversionToBool - Determines whether this conversion is 219/// a conversion of a pointer or pointer-to-member to bool. This is 220/// used as part of the ranking of standard conversion sequences 221/// (C++ 13.3.3.2p4). 222bool StandardConversionSequence::isPointerConversionToBool() const { 223 // Note that FromType has not necessarily been transformed by the 224 // array-to-pointer or function-to-pointer implicit conversions, so 225 // check for their presence as well as checking whether FromType is 226 // a pointer. 227 if (getToType(1)->isBooleanType() && 228 (getFromType()->isPointerType() || 229 getFromType()->isObjCObjectPointerType() || 230 getFromType()->isBlockPointerType() || 231 getFromType()->isNullPtrType() || 232 First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer)) 233 return true; 234 235 return false; 236} 237 238/// isPointerConversionToVoidPointer - Determines whether this 239/// conversion is a conversion of a pointer to a void pointer. This is 240/// used as part of the ranking of standard conversion sequences (C++ 241/// 13.3.3.2p4). 242bool 243StandardConversionSequence:: 244isPointerConversionToVoidPointer(ASTContext& Context) const { 245 QualType FromType = getFromType(); 246 QualType ToType = getToType(1); 247 248 // Note that FromType has not necessarily been transformed by the 249 // array-to-pointer implicit conversion, so check for its presence 250 // and redo the conversion to get a pointer. 251 if (First == ICK_Array_To_Pointer) 252 FromType = Context.getArrayDecayedType(FromType); 253 254 if (Second == ICK_Pointer_Conversion && FromType->isAnyPointerType()) 255 if (const PointerType* ToPtrType = ToType->getAs<PointerType>()) 256 return ToPtrType->getPointeeType()->isVoidType(); 257 258 return false; 259} 260 261/// DebugPrint - Print this standard conversion sequence to standard 262/// error. Useful for debugging overloading issues. 263void StandardConversionSequence::DebugPrint() const { 264 raw_ostream &OS = llvm::errs(); 265 bool PrintedSomething = false; 266 if (First != ICK_Identity) { 267 OS << GetImplicitConversionName(First); 268 PrintedSomething = true; 269 } 270 271 if (Second != ICK_Identity) { 272 if (PrintedSomething) { 273 OS << " -> "; 274 } 275 OS << GetImplicitConversionName(Second); 276 277 if (CopyConstructor) { 278 OS << " (by copy constructor)"; 279 } else if (DirectBinding) { 280 OS << " (direct reference binding)"; 281 } else if (ReferenceBinding) { 282 OS << " (reference binding)"; 283 } 284 PrintedSomething = true; 285 } 286 287 if (Third != ICK_Identity) { 288 if (PrintedSomething) { 289 OS << " -> "; 290 } 291 OS << GetImplicitConversionName(Third); 292 PrintedSomething = true; 293 } 294 295 if (!PrintedSomething) { 296 OS << "No conversions required"; 297 } 298} 299 300/// DebugPrint - Print this user-defined conversion sequence to standard 301/// error. Useful for debugging overloading issues. 302void UserDefinedConversionSequence::DebugPrint() const { 303 raw_ostream &OS = llvm::errs(); 304 if (Before.First || Before.Second || Before.Third) { 305 Before.DebugPrint(); 306 OS << " -> "; 307 } 308 if (ConversionFunction) 309 OS << '\'' << *ConversionFunction << '\''; 310 else 311 OS << "aggregate initialization"; 312 if (After.First || After.Second || After.Third) { 313 OS << " -> "; 314 After.DebugPrint(); 315 } 316} 317 318/// DebugPrint - Print this implicit conversion sequence to standard 319/// error. Useful for debugging overloading issues. 320void ImplicitConversionSequence::DebugPrint() const { 321 raw_ostream &OS = llvm::errs(); 322 switch (ConversionKind) { 323 case StandardConversion: 324 OS << "Standard conversion: "; 325 Standard.DebugPrint(); 326 break; 327 case UserDefinedConversion: 328 OS << "User-defined conversion: "; 329 UserDefined.DebugPrint(); 330 break; 331 case EllipsisConversion: 332 OS << "Ellipsis conversion"; 333 break; 334 case AmbiguousConversion: 335 OS << "Ambiguous conversion"; 336 break; 337 case BadConversion: 338 OS << "Bad conversion"; 339 break; 340 } 341 342 OS << "\n"; 343} 344 345void AmbiguousConversionSequence::construct() { 346 new (&conversions()) ConversionSet(); 347} 348 349void AmbiguousConversionSequence::destruct() { 350 conversions().~ConversionSet(); 351} 352 353void 354AmbiguousConversionSequence::copyFrom(const AmbiguousConversionSequence &O) { 355 FromTypePtr = O.FromTypePtr; 356 ToTypePtr = O.ToTypePtr; 357 new (&conversions()) ConversionSet(O.conversions()); 358} 359 360namespace { 361 // Structure used by OverloadCandidate::DeductionFailureInfo to store 362 // template parameter and template argument information. 363 struct DFIParamWithArguments { 364 TemplateParameter Param; 365 TemplateArgument FirstArg; 366 TemplateArgument SecondArg; 367 }; 368} 369 370/// \brief Convert from Sema's representation of template deduction information 371/// to the form used in overload-candidate information. 372OverloadCandidate::DeductionFailureInfo 373static MakeDeductionFailureInfo(ASTContext &Context, 374 Sema::TemplateDeductionResult TDK, 375 TemplateDeductionInfo &Info) { 376 OverloadCandidate::DeductionFailureInfo Result; 377 Result.Result = static_cast<unsigned>(TDK); 378 Result.Data = 0; 379 switch (TDK) { 380 case Sema::TDK_Success: 381 case Sema::TDK_InstantiationDepth: 382 case Sema::TDK_TooManyArguments: 383 case Sema::TDK_TooFewArguments: 384 break; 385 386 case Sema::TDK_Incomplete: 387 case Sema::TDK_InvalidExplicitArguments: 388 Result.Data = Info.Param.getOpaqueValue(); 389 break; 390 391 case Sema::TDK_Inconsistent: 392 case Sema::TDK_Underqualified: { 393 // FIXME: Should allocate from normal heap so that we can free this later. 394 DFIParamWithArguments *Saved = new (Context) DFIParamWithArguments; 395 Saved->Param = Info.Param; 396 Saved->FirstArg = Info.FirstArg; 397 Saved->SecondArg = Info.SecondArg; 398 Result.Data = Saved; 399 break; 400 } 401 402 case Sema::TDK_SubstitutionFailure: 403 Result.Data = Info.take(); 404 break; 405 406 case Sema::TDK_NonDeducedMismatch: 407 case Sema::TDK_FailedOverloadResolution: 408 break; 409 } 410 411 return Result; 412} 413 414void OverloadCandidate::DeductionFailureInfo::Destroy() { 415 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 416 case Sema::TDK_Success: 417 case Sema::TDK_InstantiationDepth: 418 case Sema::TDK_Incomplete: 419 case Sema::TDK_TooManyArguments: 420 case Sema::TDK_TooFewArguments: 421 case Sema::TDK_InvalidExplicitArguments: 422 break; 423 424 case Sema::TDK_Inconsistent: 425 case Sema::TDK_Underqualified: 426 // FIXME: Destroy the data? 427 Data = 0; 428 break; 429 430 case Sema::TDK_SubstitutionFailure: 431 // FIXME: Destroy the template arugment list? 432 Data = 0; 433 break; 434 435 // Unhandled 436 case Sema::TDK_NonDeducedMismatch: 437 case Sema::TDK_FailedOverloadResolution: 438 break; 439 } 440} 441 442TemplateParameter 443OverloadCandidate::DeductionFailureInfo::getTemplateParameter() { 444 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 445 case Sema::TDK_Success: 446 case Sema::TDK_InstantiationDepth: 447 case Sema::TDK_TooManyArguments: 448 case Sema::TDK_TooFewArguments: 449 case Sema::TDK_SubstitutionFailure: 450 return TemplateParameter(); 451 452 case Sema::TDK_Incomplete: 453 case Sema::TDK_InvalidExplicitArguments: 454 return TemplateParameter::getFromOpaqueValue(Data); 455 456 case Sema::TDK_Inconsistent: 457 case Sema::TDK_Underqualified: 458 return static_cast<DFIParamWithArguments*>(Data)->Param; 459 460 // Unhandled 461 case Sema::TDK_NonDeducedMismatch: 462 case Sema::TDK_FailedOverloadResolution: 463 break; 464 } 465 466 return TemplateParameter(); 467} 468 469TemplateArgumentList * 470OverloadCandidate::DeductionFailureInfo::getTemplateArgumentList() { 471 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 472 case Sema::TDK_Success: 473 case Sema::TDK_InstantiationDepth: 474 case Sema::TDK_TooManyArguments: 475 case Sema::TDK_TooFewArguments: 476 case Sema::TDK_Incomplete: 477 case Sema::TDK_InvalidExplicitArguments: 478 case Sema::TDK_Inconsistent: 479 case Sema::TDK_Underqualified: 480 return 0; 481 482 case Sema::TDK_SubstitutionFailure: 483 return static_cast<TemplateArgumentList*>(Data); 484 485 // Unhandled 486 case Sema::TDK_NonDeducedMismatch: 487 case Sema::TDK_FailedOverloadResolution: 488 break; 489 } 490 491 return 0; 492} 493 494const TemplateArgument *OverloadCandidate::DeductionFailureInfo::getFirstArg() { 495 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 496 case Sema::TDK_Success: 497 case Sema::TDK_InstantiationDepth: 498 case Sema::TDK_Incomplete: 499 case Sema::TDK_TooManyArguments: 500 case Sema::TDK_TooFewArguments: 501 case Sema::TDK_InvalidExplicitArguments: 502 case Sema::TDK_SubstitutionFailure: 503 return 0; 504 505 case Sema::TDK_Inconsistent: 506 case Sema::TDK_Underqualified: 507 return &static_cast<DFIParamWithArguments*>(Data)->FirstArg; 508 509 // Unhandled 510 case Sema::TDK_NonDeducedMismatch: 511 case Sema::TDK_FailedOverloadResolution: 512 break; 513 } 514 515 return 0; 516} 517 518const TemplateArgument * 519OverloadCandidate::DeductionFailureInfo::getSecondArg() { 520 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 521 case Sema::TDK_Success: 522 case Sema::TDK_InstantiationDepth: 523 case Sema::TDK_Incomplete: 524 case Sema::TDK_TooManyArguments: 525 case Sema::TDK_TooFewArguments: 526 case Sema::TDK_InvalidExplicitArguments: 527 case Sema::TDK_SubstitutionFailure: 528 return 0; 529 530 case Sema::TDK_Inconsistent: 531 case Sema::TDK_Underqualified: 532 return &static_cast<DFIParamWithArguments*>(Data)->SecondArg; 533 534 // Unhandled 535 case Sema::TDK_NonDeducedMismatch: 536 case Sema::TDK_FailedOverloadResolution: 537 break; 538 } 539 540 return 0; 541} 542 543void OverloadCandidateSet::clear() { 544 inherited::clear(); 545 Functions.clear(); 546} 547 548namespace { 549 class UnbridgedCastsSet { 550 struct Entry { 551 Expr **Addr; 552 Expr *Saved; 553 }; 554 SmallVector<Entry, 2> Entries; 555 556 public: 557 void save(Sema &S, Expr *&E) { 558 assert(E->hasPlaceholderType(BuiltinType::ARCUnbridgedCast)); 559 Entry entry = { &E, E }; 560 Entries.push_back(entry); 561 E = S.stripARCUnbridgedCast(E); 562 } 563 564 void restore() { 565 for (SmallVectorImpl<Entry>::iterator 566 i = Entries.begin(), e = Entries.end(); i != e; ++i) 567 *i->Addr = i->Saved; 568 } 569 }; 570} 571 572/// checkPlaceholderForOverload - Do any interesting placeholder-like 573/// preprocessing on the given expression. 574/// 575/// \param unbridgedCasts a collection to which to add unbridged casts; 576/// without this, they will be immediately diagnosed as errors 577/// 578/// Return true on unrecoverable error. 579static bool checkPlaceholderForOverload(Sema &S, Expr *&E, 580 UnbridgedCastsSet *unbridgedCasts = 0) { 581 if (const BuiltinType *placeholder = E->getType()->getAsPlaceholderType()) { 582 // We can't handle overloaded expressions here because overload 583 // resolution might reasonably tweak them. 584 if (placeholder->getKind() == BuiltinType::Overload) return false; 585 586 // If the context potentially accepts unbridged ARC casts, strip 587 // the unbridged cast and add it to the collection for later restoration. 588 if (placeholder->getKind() == BuiltinType::ARCUnbridgedCast && 589 unbridgedCasts) { 590 unbridgedCasts->save(S, E); 591 return false; 592 } 593 594 // Go ahead and check everything else. 595 ExprResult result = S.CheckPlaceholderExpr(E); 596 if (result.isInvalid()) 597 return true; 598 599 E = result.take(); 600 return false; 601 } 602 603 // Nothing to do. 604 return false; 605} 606 607/// checkArgPlaceholdersForOverload - Check a set of call operands for 608/// placeholders. 609static bool checkArgPlaceholdersForOverload(Sema &S, Expr **args, 610 unsigned numArgs, 611 UnbridgedCastsSet &unbridged) { 612 for (unsigned i = 0; i != numArgs; ++i) 613 if (checkPlaceholderForOverload(S, args[i], &unbridged)) 614 return true; 615 616 return false; 617} 618 619// IsOverload - Determine whether the given New declaration is an 620// overload of the declarations in Old. This routine returns false if 621// New and Old cannot be overloaded, e.g., if New has the same 622// signature as some function in Old (C++ 1.3.10) or if the Old 623// declarations aren't functions (or function templates) at all. When 624// it does return false, MatchedDecl will point to the decl that New 625// cannot be overloaded with. This decl may be a UsingShadowDecl on 626// top of the underlying declaration. 627// 628// Example: Given the following input: 629// 630// void f(int, float); // #1 631// void f(int, int); // #2 632// int f(int, int); // #3 633// 634// When we process #1, there is no previous declaration of "f", 635// so IsOverload will not be used. 636// 637// When we process #2, Old contains only the FunctionDecl for #1. By 638// comparing the parameter types, we see that #1 and #2 are overloaded 639// (since they have different signatures), so this routine returns 640// false; MatchedDecl is unchanged. 641// 642// When we process #3, Old is an overload set containing #1 and #2. We 643// compare the signatures of #3 to #1 (they're overloaded, so we do 644// nothing) and then #3 to #2. Since the signatures of #3 and #2 are 645// identical (return types of functions are not part of the 646// signature), IsOverload returns false and MatchedDecl will be set to 647// point to the FunctionDecl for #2. 648// 649// 'NewIsUsingShadowDecl' indicates that 'New' is being introduced 650// into a class by a using declaration. The rules for whether to hide 651// shadow declarations ignore some properties which otherwise figure 652// into a function template's signature. 653Sema::OverloadKind 654Sema::CheckOverload(Scope *S, FunctionDecl *New, const LookupResult &Old, 655 NamedDecl *&Match, bool NewIsUsingDecl) { 656 for (LookupResult::iterator I = Old.begin(), E = Old.end(); 657 I != E; ++I) { 658 NamedDecl *OldD = *I; 659 660 bool OldIsUsingDecl = false; 661 if (isa<UsingShadowDecl>(OldD)) { 662 OldIsUsingDecl = true; 663 664 // We can always introduce two using declarations into the same 665 // context, even if they have identical signatures. 666 if (NewIsUsingDecl) continue; 667 668 OldD = cast<UsingShadowDecl>(OldD)->getTargetDecl(); 669 } 670 671 // If either declaration was introduced by a using declaration, 672 // we'll need to use slightly different rules for matching. 673 // Essentially, these rules are the normal rules, except that 674 // function templates hide function templates with different 675 // return types or template parameter lists. 676 bool UseMemberUsingDeclRules = 677 (OldIsUsingDecl || NewIsUsingDecl) && CurContext->isRecord(); 678 679 if (FunctionTemplateDecl *OldT = dyn_cast<FunctionTemplateDecl>(OldD)) { 680 if (!IsOverload(New, OldT->getTemplatedDecl(), UseMemberUsingDeclRules)) { 681 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 682 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 683 continue; 684 } 685 686 Match = *I; 687 return Ovl_Match; 688 } 689 } else if (FunctionDecl *OldF = dyn_cast<FunctionDecl>(OldD)) { 690 if (!IsOverload(New, OldF, UseMemberUsingDeclRules)) { 691 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 692 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 693 continue; 694 } 695 696 Match = *I; 697 return Ovl_Match; 698 } 699 } else if (isa<UsingDecl>(OldD)) { 700 // We can overload with these, which can show up when doing 701 // redeclaration checks for UsingDecls. 702 assert(Old.getLookupKind() == LookupUsingDeclName); 703 } else if (isa<TagDecl>(OldD)) { 704 // We can always overload with tags by hiding them. 705 } else if (isa<UnresolvedUsingValueDecl>(OldD)) { 706 // Optimistically assume that an unresolved using decl will 707 // overload; if it doesn't, we'll have to diagnose during 708 // template instantiation. 709 } else { 710 // (C++ 13p1): 711 // Only function declarations can be overloaded; object and type 712 // declarations cannot be overloaded. 713 Match = *I; 714 return Ovl_NonFunction; 715 } 716 } 717 718 return Ovl_Overload; 719} 720 721bool Sema::IsOverload(FunctionDecl *New, FunctionDecl *Old, 722 bool UseUsingDeclRules) { 723 // If both of the functions are extern "C", then they are not 724 // overloads. 725 if (Old->isExternC() && New->isExternC()) 726 return false; 727 728 FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate(); 729 FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate(); 730 731 // C++ [temp.fct]p2: 732 // A function template can be overloaded with other function templates 733 // and with normal (non-template) functions. 734 if ((OldTemplate == 0) != (NewTemplate == 0)) 735 return true; 736 737 // Is the function New an overload of the function Old? 738 QualType OldQType = Context.getCanonicalType(Old->getType()); 739 QualType NewQType = Context.getCanonicalType(New->getType()); 740 741 // Compare the signatures (C++ 1.3.10) of the two functions to 742 // determine whether they are overloads. If we find any mismatch 743 // in the signature, they are overloads. 744 745 // If either of these functions is a K&R-style function (no 746 // prototype), then we consider them to have matching signatures. 747 if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) || 748 isa<FunctionNoProtoType>(NewQType.getTypePtr())) 749 return false; 750 751 const FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType); 752 const FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType); 753 754 // The signature of a function includes the types of its 755 // parameters (C++ 1.3.10), which includes the presence or absence 756 // of the ellipsis; see C++ DR 357). 757 if (OldQType != NewQType && 758 (OldType->getNumArgs() != NewType->getNumArgs() || 759 OldType->isVariadic() != NewType->isVariadic() || 760 !FunctionArgTypesAreEqual(OldType, NewType))) 761 return true; 762 763 // C++ [temp.over.link]p4: 764 // The signature of a function template consists of its function 765 // signature, its return type and its template parameter list. The names 766 // of the template parameters are significant only for establishing the 767 // relationship between the template parameters and the rest of the 768 // signature. 769 // 770 // We check the return type and template parameter lists for function 771 // templates first; the remaining checks follow. 772 // 773 // However, we don't consider either of these when deciding whether 774 // a member introduced by a shadow declaration is hidden. 775 if (!UseUsingDeclRules && NewTemplate && 776 (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(), 777 OldTemplate->getTemplateParameters(), 778 false, TPL_TemplateMatch) || 779 OldType->getResultType() != NewType->getResultType())) 780 return true; 781 782 // If the function is a class member, its signature includes the 783 // cv-qualifiers (if any) and ref-qualifier (if any) on the function itself. 784 // 785 // As part of this, also check whether one of the member functions 786 // is static, in which case they are not overloads (C++ 787 // 13.1p2). While not part of the definition of the signature, 788 // this check is important to determine whether these functions 789 // can be overloaded. 790 CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 791 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 792 if (OldMethod && NewMethod && 793 !OldMethod->isStatic() && !NewMethod->isStatic() && 794 (OldMethod->getTypeQualifiers() != NewMethod->getTypeQualifiers() || 795 OldMethod->getRefQualifier() != NewMethod->getRefQualifier())) { 796 if (!UseUsingDeclRules && 797 OldMethod->getRefQualifier() != NewMethod->getRefQualifier() && 798 (OldMethod->getRefQualifier() == RQ_None || 799 NewMethod->getRefQualifier() == RQ_None)) { 800 // C++0x [over.load]p2: 801 // - Member function declarations with the same name and the same 802 // parameter-type-list as well as member function template 803 // declarations with the same name, the same parameter-type-list, and 804 // the same template parameter lists cannot be overloaded if any of 805 // them, but not all, have a ref-qualifier (8.3.5). 806 Diag(NewMethod->getLocation(), diag::err_ref_qualifier_overload) 807 << NewMethod->getRefQualifier() << OldMethod->getRefQualifier(); 808 Diag(OldMethod->getLocation(), diag::note_previous_declaration); 809 } 810 811 return true; 812 } 813 814 // The signatures match; this is not an overload. 815 return false; 816} 817 818/// \brief Checks availability of the function depending on the current 819/// function context. Inside an unavailable function, unavailability is ignored. 820/// 821/// \returns true if \arg FD is unavailable and current context is inside 822/// an available function, false otherwise. 823bool Sema::isFunctionConsideredUnavailable(FunctionDecl *FD) { 824 return FD->isUnavailable() && !cast<Decl>(CurContext)->isUnavailable(); 825} 826 827/// TryImplicitConversion - Attempt to perform an implicit conversion 828/// from the given expression (Expr) to the given type (ToType). This 829/// function returns an implicit conversion sequence that can be used 830/// to perform the initialization. Given 831/// 832/// void f(float f); 833/// void g(int i) { f(i); } 834/// 835/// this routine would produce an implicit conversion sequence to 836/// describe the initialization of f from i, which will be a standard 837/// conversion sequence containing an lvalue-to-rvalue conversion (C++ 838/// 4.1) followed by a floating-integral conversion (C++ 4.9). 839// 840/// Note that this routine only determines how the conversion can be 841/// performed; it does not actually perform the conversion. As such, 842/// it will not produce any diagnostics if no conversion is available, 843/// but will instead return an implicit conversion sequence of kind 844/// "BadConversion". 845/// 846/// If @p SuppressUserConversions, then user-defined conversions are 847/// not permitted. 848/// If @p AllowExplicit, then explicit user-defined conversions are 849/// permitted. 850/// 851/// \param AllowObjCWritebackConversion Whether we allow the Objective-C 852/// writeback conversion, which allows __autoreleasing id* parameters to 853/// be initialized with __strong id* or __weak id* arguments. 854static ImplicitConversionSequence 855TryImplicitConversion(Sema &S, Expr *From, QualType ToType, 856 bool SuppressUserConversions, 857 bool AllowExplicit, 858 bool InOverloadResolution, 859 bool CStyle, 860 bool AllowObjCWritebackConversion) { 861 ImplicitConversionSequence ICS; 862 if (IsStandardConversion(S, From, ToType, InOverloadResolution, 863 ICS.Standard, CStyle, AllowObjCWritebackConversion)){ 864 ICS.setStandard(); 865 return ICS; 866 } 867 868 if (!S.getLangOptions().CPlusPlus) { 869 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 870 return ICS; 871 } 872 873 // C++ [over.ics.user]p4: 874 // A conversion of an expression of class type to the same class 875 // type is given Exact Match rank, and a conversion of an 876 // expression of class type to a base class of that type is 877 // given Conversion rank, in spite of the fact that a copy/move 878 // constructor (i.e., a user-defined conversion function) is 879 // called for those cases. 880 QualType FromType = From->getType(); 881 if (ToType->getAs<RecordType>() && FromType->getAs<RecordType>() && 882 (S.Context.hasSameUnqualifiedType(FromType, ToType) || 883 S.IsDerivedFrom(FromType, ToType))) { 884 ICS.setStandard(); 885 ICS.Standard.setAsIdentityConversion(); 886 ICS.Standard.setFromType(FromType); 887 ICS.Standard.setAllToTypes(ToType); 888 889 // We don't actually check at this point whether there is a valid 890 // copy/move constructor, since overloading just assumes that it 891 // exists. When we actually perform initialization, we'll find the 892 // appropriate constructor to copy the returned object, if needed. 893 ICS.Standard.CopyConstructor = 0; 894 895 // Determine whether this is considered a derived-to-base conversion. 896 if (!S.Context.hasSameUnqualifiedType(FromType, ToType)) 897 ICS.Standard.Second = ICK_Derived_To_Base; 898 899 return ICS; 900 } 901 902 if (SuppressUserConversions) { 903 // We're not in the case above, so there is no conversion that 904 // we can perform. 905 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 906 return ICS; 907 } 908 909 // Attempt user-defined conversion. 910 OverloadCandidateSet Conversions(From->getExprLoc()); 911 OverloadingResult UserDefResult 912 = IsUserDefinedConversion(S, From, ToType, ICS.UserDefined, Conversions, 913 AllowExplicit); 914 915 if (UserDefResult == OR_Success) { 916 ICS.setUserDefined(); 917 // C++ [over.ics.user]p4: 918 // A conversion of an expression of class type to the same class 919 // type is given Exact Match rank, and a conversion of an 920 // expression of class type to a base class of that type is 921 // given Conversion rank, in spite of the fact that a copy 922 // constructor (i.e., a user-defined conversion function) is 923 // called for those cases. 924 if (CXXConstructorDecl *Constructor 925 = dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) { 926 QualType FromCanon 927 = S.Context.getCanonicalType(From->getType().getUnqualifiedType()); 928 QualType ToCanon 929 = S.Context.getCanonicalType(ToType).getUnqualifiedType(); 930 if (Constructor->isCopyConstructor() && 931 (FromCanon == ToCanon || S.IsDerivedFrom(FromCanon, ToCanon))) { 932 // Turn this into a "standard" conversion sequence, so that it 933 // gets ranked with standard conversion sequences. 934 ICS.setStandard(); 935 ICS.Standard.setAsIdentityConversion(); 936 ICS.Standard.setFromType(From->getType()); 937 ICS.Standard.setAllToTypes(ToType); 938 ICS.Standard.CopyConstructor = Constructor; 939 if (ToCanon != FromCanon) 940 ICS.Standard.Second = ICK_Derived_To_Base; 941 } 942 } 943 944 // C++ [over.best.ics]p4: 945 // However, when considering the argument of a user-defined 946 // conversion function that is a candidate by 13.3.1.3 when 947 // invoked for the copying of the temporary in the second step 948 // of a class copy-initialization, or by 13.3.1.4, 13.3.1.5, or 949 // 13.3.1.6 in all cases, only standard conversion sequences and 950 // ellipsis conversion sequences are allowed. 951 if (SuppressUserConversions && ICS.isUserDefined()) { 952 ICS.setBad(BadConversionSequence::suppressed_user, From, ToType); 953 } 954 } else if (UserDefResult == OR_Ambiguous && !SuppressUserConversions) { 955 ICS.setAmbiguous(); 956 ICS.Ambiguous.setFromType(From->getType()); 957 ICS.Ambiguous.setToType(ToType); 958 for (OverloadCandidateSet::iterator Cand = Conversions.begin(); 959 Cand != Conversions.end(); ++Cand) 960 if (Cand->Viable) 961 ICS.Ambiguous.addConversion(Cand->Function); 962 } else { 963 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 964 } 965 966 return ICS; 967} 968 969ImplicitConversionSequence 970Sema::TryImplicitConversion(Expr *From, QualType ToType, 971 bool SuppressUserConversions, 972 bool AllowExplicit, 973 bool InOverloadResolution, 974 bool CStyle, 975 bool AllowObjCWritebackConversion) { 976 return clang::TryImplicitConversion(*this, From, ToType, 977 SuppressUserConversions, AllowExplicit, 978 InOverloadResolution, CStyle, 979 AllowObjCWritebackConversion); 980} 981 982/// PerformImplicitConversion - Perform an implicit conversion of the 983/// expression From to the type ToType. Returns the 984/// converted expression. Flavor is the kind of conversion we're 985/// performing, used in the error message. If @p AllowExplicit, 986/// explicit user-defined conversions are permitted. 987ExprResult 988Sema::PerformImplicitConversion(Expr *From, QualType ToType, 989 AssignmentAction Action, bool AllowExplicit) { 990 ImplicitConversionSequence ICS; 991 return PerformImplicitConversion(From, ToType, Action, AllowExplicit, ICS); 992} 993 994ExprResult 995Sema::PerformImplicitConversion(Expr *From, QualType ToType, 996 AssignmentAction Action, bool AllowExplicit, 997 ImplicitConversionSequence& ICS) { 998 if (checkPlaceholderForOverload(*this, From)) 999 return ExprError(); 1000 1001 // Objective-C ARC: Determine whether we will allow the writeback conversion. 1002 bool AllowObjCWritebackConversion 1003 = getLangOptions().ObjCAutoRefCount && 1004 (Action == AA_Passing || Action == AA_Sending); 1005 1006 ICS = clang::TryImplicitConversion(*this, From, ToType, 1007 /*SuppressUserConversions=*/false, 1008 AllowExplicit, 1009 /*InOverloadResolution=*/false, 1010 /*CStyle=*/false, 1011 AllowObjCWritebackConversion); 1012 return PerformImplicitConversion(From, ToType, ICS, Action); 1013} 1014 1015/// \brief Determine whether the conversion from FromType to ToType is a valid 1016/// conversion that strips "noreturn" off the nested function type. 1017bool Sema::IsNoReturnConversion(QualType FromType, QualType ToType, 1018 QualType &ResultTy) { 1019 if (Context.hasSameUnqualifiedType(FromType, ToType)) 1020 return false; 1021 1022 // Permit the conversion F(t __attribute__((noreturn))) -> F(t) 1023 // where F adds one of the following at most once: 1024 // - a pointer 1025 // - a member pointer 1026 // - a block pointer 1027 CanQualType CanTo = Context.getCanonicalType(ToType); 1028 CanQualType CanFrom = Context.getCanonicalType(FromType); 1029 Type::TypeClass TyClass = CanTo->getTypeClass(); 1030 if (TyClass != CanFrom->getTypeClass()) return false; 1031 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) { 1032 if (TyClass == Type::Pointer) { 1033 CanTo = CanTo.getAs<PointerType>()->getPointeeType(); 1034 CanFrom = CanFrom.getAs<PointerType>()->getPointeeType(); 1035 } else if (TyClass == Type::BlockPointer) { 1036 CanTo = CanTo.getAs<BlockPointerType>()->getPointeeType(); 1037 CanFrom = CanFrom.getAs<BlockPointerType>()->getPointeeType(); 1038 } else if (TyClass == Type::MemberPointer) { 1039 CanTo = CanTo.getAs<MemberPointerType>()->getPointeeType(); 1040 CanFrom = CanFrom.getAs<MemberPointerType>()->getPointeeType(); 1041 } else { 1042 return false; 1043 } 1044 1045 TyClass = CanTo->getTypeClass(); 1046 if (TyClass != CanFrom->getTypeClass()) return false; 1047 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) 1048 return false; 1049 } 1050 1051 const FunctionType *FromFn = cast<FunctionType>(CanFrom); 1052 FunctionType::ExtInfo EInfo = FromFn->getExtInfo(); 1053 if (!EInfo.getNoReturn()) return false; 1054 1055 FromFn = Context.adjustFunctionType(FromFn, EInfo.withNoReturn(false)); 1056 assert(QualType(FromFn, 0).isCanonical()); 1057 if (QualType(FromFn, 0) != CanTo) return false; 1058 1059 ResultTy = ToType; 1060 return true; 1061} 1062 1063/// \brief Determine whether the conversion from FromType to ToType is a valid 1064/// vector conversion. 1065/// 1066/// \param ICK Will be set to the vector conversion kind, if this is a vector 1067/// conversion. 1068static bool IsVectorConversion(ASTContext &Context, QualType FromType, 1069 QualType ToType, ImplicitConversionKind &ICK) { 1070 // We need at least one of these types to be a vector type to have a vector 1071 // conversion. 1072 if (!ToType->isVectorType() && !FromType->isVectorType()) 1073 return false; 1074 1075 // Identical types require no conversions. 1076 if (Context.hasSameUnqualifiedType(FromType, ToType)) 1077 return false; 1078 1079 // There are no conversions between extended vector types, only identity. 1080 if (ToType->isExtVectorType()) { 1081 // There are no conversions between extended vector types other than the 1082 // identity conversion. 1083 if (FromType->isExtVectorType()) 1084 return false; 1085 1086 // Vector splat from any arithmetic type to a vector. 1087 if (FromType->isArithmeticType()) { 1088 ICK = ICK_Vector_Splat; 1089 return true; 1090 } 1091 } 1092 1093 // We can perform the conversion between vector types in the following cases: 1094 // 1)vector types are equivalent AltiVec and GCC vector types 1095 // 2)lax vector conversions are permitted and the vector types are of the 1096 // same size 1097 if (ToType->isVectorType() && FromType->isVectorType()) { 1098 if (Context.areCompatibleVectorTypes(FromType, ToType) || 1099 (Context.getLangOptions().LaxVectorConversions && 1100 (Context.getTypeSize(FromType) == Context.getTypeSize(ToType)))) { 1101 ICK = ICK_Vector_Conversion; 1102 return true; 1103 } 1104 } 1105 1106 return false; 1107} 1108 1109/// IsStandardConversion - Determines whether there is a standard 1110/// conversion sequence (C++ [conv], C++ [over.ics.scs]) from the 1111/// expression From to the type ToType. Standard conversion sequences 1112/// only consider non-class types; for conversions that involve class 1113/// types, use TryImplicitConversion. If a conversion exists, SCS will 1114/// contain the standard conversion sequence required to perform this 1115/// conversion and this routine will return true. Otherwise, this 1116/// routine will return false and the value of SCS is unspecified. 1117static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 1118 bool InOverloadResolution, 1119 StandardConversionSequence &SCS, 1120 bool CStyle, 1121 bool AllowObjCWritebackConversion) { 1122 QualType FromType = From->getType(); 1123 1124 // Standard conversions (C++ [conv]) 1125 SCS.setAsIdentityConversion(); 1126 SCS.DeprecatedStringLiteralToCharPtr = false; 1127 SCS.IncompatibleObjC = false; 1128 SCS.setFromType(FromType); 1129 SCS.CopyConstructor = 0; 1130 1131 // There are no standard conversions for class types in C++, so 1132 // abort early. When overloading in C, however, we do permit 1133 if (FromType->isRecordType() || ToType->isRecordType()) { 1134 if (S.getLangOptions().CPlusPlus) 1135 return false; 1136 1137 // When we're overloading in C, we allow, as standard conversions, 1138 } 1139 1140 // The first conversion can be an lvalue-to-rvalue conversion, 1141 // array-to-pointer conversion, or function-to-pointer conversion 1142 // (C++ 4p1). 1143 1144 if (FromType == S.Context.OverloadTy) { 1145 DeclAccessPair AccessPair; 1146 if (FunctionDecl *Fn 1147 = S.ResolveAddressOfOverloadedFunction(From, ToType, false, 1148 AccessPair)) { 1149 // We were able to resolve the address of the overloaded function, 1150 // so we can convert to the type of that function. 1151 FromType = Fn->getType(); 1152 1153 // we can sometimes resolve &foo<int> regardless of ToType, so check 1154 // if the type matches (identity) or we are converting to bool 1155 if (!S.Context.hasSameUnqualifiedType( 1156 S.ExtractUnqualifiedFunctionType(ToType), FromType)) { 1157 QualType resultTy; 1158 // if the function type matches except for [[noreturn]], it's ok 1159 if (!S.IsNoReturnConversion(FromType, 1160 S.ExtractUnqualifiedFunctionType(ToType), resultTy)) 1161 // otherwise, only a boolean conversion is standard 1162 if (!ToType->isBooleanType()) 1163 return false; 1164 } 1165 1166 // Check if the "from" expression is taking the address of an overloaded 1167 // function and recompute the FromType accordingly. Take advantage of the 1168 // fact that non-static member functions *must* have such an address-of 1169 // expression. 1170 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn); 1171 if (Method && !Method->isStatic()) { 1172 assert(isa<UnaryOperator>(From->IgnoreParens()) && 1173 "Non-unary operator on non-static member address"); 1174 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() 1175 == UO_AddrOf && 1176 "Non-address-of operator on non-static member address"); 1177 const Type *ClassType 1178 = S.Context.getTypeDeclType(Method->getParent()).getTypePtr(); 1179 FromType = S.Context.getMemberPointerType(FromType, ClassType); 1180 } else if (isa<UnaryOperator>(From->IgnoreParens())) { 1181 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == 1182 UO_AddrOf && 1183 "Non-address-of operator for overloaded function expression"); 1184 FromType = S.Context.getPointerType(FromType); 1185 } 1186 1187 // Check that we've computed the proper type after overload resolution. 1188 assert(S.Context.hasSameType( 1189 FromType, 1190 S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType())); 1191 } else { 1192 return false; 1193 } 1194 } 1195 // Lvalue-to-rvalue conversion (C++11 4.1): 1196 // A glvalue (3.10) of a non-function, non-array type T can 1197 // be converted to a prvalue. 1198 bool argIsLValue = From->isGLValue(); 1199 if (argIsLValue && 1200 !FromType->isFunctionType() && !FromType->isArrayType() && 1201 S.Context.getCanonicalType(FromType) != S.Context.OverloadTy) { 1202 SCS.First = ICK_Lvalue_To_Rvalue; 1203 1204 // If T is a non-class type, the type of the rvalue is the 1205 // cv-unqualified version of T. Otherwise, the type of the rvalue 1206 // is T (C++ 4.1p1). C++ can't get here with class types; in C, we 1207 // just strip the qualifiers because they don't matter. 1208 FromType = FromType.getUnqualifiedType(); 1209 } else if (FromType->isArrayType()) { 1210 // Array-to-pointer conversion (C++ 4.2) 1211 SCS.First = ICK_Array_To_Pointer; 1212 1213 // An lvalue or rvalue of type "array of N T" or "array of unknown 1214 // bound of T" can be converted to an rvalue of type "pointer to 1215 // T" (C++ 4.2p1). 1216 FromType = S.Context.getArrayDecayedType(FromType); 1217 1218 if (S.IsStringLiteralToNonConstPointerConversion(From, ToType)) { 1219 // This conversion is deprecated. (C++ D.4). 1220 SCS.DeprecatedStringLiteralToCharPtr = true; 1221 1222 // For the purpose of ranking in overload resolution 1223 // (13.3.3.1.1), this conversion is considered an 1224 // array-to-pointer conversion followed by a qualification 1225 // conversion (4.4). (C++ 4.2p2) 1226 SCS.Second = ICK_Identity; 1227 SCS.Third = ICK_Qualification; 1228 SCS.QualificationIncludesObjCLifetime = false; 1229 SCS.setAllToTypes(FromType); 1230 return true; 1231 } 1232 } else if (FromType->isFunctionType() && argIsLValue) { 1233 // Function-to-pointer conversion (C++ 4.3). 1234 SCS.First = ICK_Function_To_Pointer; 1235 1236 // An lvalue of function type T can be converted to an rvalue of 1237 // type "pointer to T." The result is a pointer to the 1238 // function. (C++ 4.3p1). 1239 FromType = S.Context.getPointerType(FromType); 1240 } else { 1241 // We don't require any conversions for the first step. 1242 SCS.First = ICK_Identity; 1243 } 1244 SCS.setToType(0, FromType); 1245 1246 // The second conversion can be an integral promotion, floating 1247 // point promotion, integral conversion, floating point conversion, 1248 // floating-integral conversion, pointer conversion, 1249 // pointer-to-member conversion, or boolean conversion (C++ 4p1). 1250 // For overloading in C, this can also be a "compatible-type" 1251 // conversion. 1252 bool IncompatibleObjC = false; 1253 ImplicitConversionKind SecondICK = ICK_Identity; 1254 if (S.Context.hasSameUnqualifiedType(FromType, ToType)) { 1255 // The unqualified versions of the types are the same: there's no 1256 // conversion to do. 1257 SCS.Second = ICK_Identity; 1258 } else if (S.IsIntegralPromotion(From, FromType, ToType)) { 1259 // Integral promotion (C++ 4.5). 1260 SCS.Second = ICK_Integral_Promotion; 1261 FromType = ToType.getUnqualifiedType(); 1262 } else if (S.IsFloatingPointPromotion(FromType, ToType)) { 1263 // Floating point promotion (C++ 4.6). 1264 SCS.Second = ICK_Floating_Promotion; 1265 FromType = ToType.getUnqualifiedType(); 1266 } else if (S.IsComplexPromotion(FromType, ToType)) { 1267 // Complex promotion (Clang extension) 1268 SCS.Second = ICK_Complex_Promotion; 1269 FromType = ToType.getUnqualifiedType(); 1270 } else if (ToType->isBooleanType() && 1271 (FromType->isArithmeticType() || 1272 FromType->isAnyPointerType() || 1273 FromType->isBlockPointerType() || 1274 FromType->isMemberPointerType() || 1275 FromType->isNullPtrType())) { 1276 // Boolean conversions (C++ 4.12). 1277 SCS.Second = ICK_Boolean_Conversion; 1278 FromType = S.Context.BoolTy; 1279 } else if (FromType->isIntegralOrUnscopedEnumerationType() && 1280 ToType->isIntegralType(S.Context)) { 1281 // Integral conversions (C++ 4.7). 1282 SCS.Second = ICK_Integral_Conversion; 1283 FromType = ToType.getUnqualifiedType(); 1284 } else if (FromType->isAnyComplexType() && ToType->isComplexType()) { 1285 // Complex conversions (C99 6.3.1.6) 1286 SCS.Second = ICK_Complex_Conversion; 1287 FromType = ToType.getUnqualifiedType(); 1288 } else if ((FromType->isAnyComplexType() && ToType->isArithmeticType()) || 1289 (ToType->isAnyComplexType() && FromType->isArithmeticType())) { 1290 // Complex-real conversions (C99 6.3.1.7) 1291 SCS.Second = ICK_Complex_Real; 1292 FromType = ToType.getUnqualifiedType(); 1293 } else if (FromType->isRealFloatingType() && ToType->isRealFloatingType()) { 1294 // Floating point conversions (C++ 4.8). 1295 SCS.Second = ICK_Floating_Conversion; 1296 FromType = ToType.getUnqualifiedType(); 1297 } else if ((FromType->isRealFloatingType() && 1298 ToType->isIntegralType(S.Context)) || 1299 (FromType->isIntegralOrUnscopedEnumerationType() && 1300 ToType->isRealFloatingType())) { 1301 // Floating-integral conversions (C++ 4.9). 1302 SCS.Second = ICK_Floating_Integral; 1303 FromType = ToType.getUnqualifiedType(); 1304 } else if (S.IsBlockPointerConversion(FromType, ToType, FromType)) { 1305 SCS.Second = ICK_Block_Pointer_Conversion; 1306 } else if (AllowObjCWritebackConversion && 1307 S.isObjCWritebackConversion(FromType, ToType, FromType)) { 1308 SCS.Second = ICK_Writeback_Conversion; 1309 } else if (S.IsPointerConversion(From, FromType, ToType, InOverloadResolution, 1310 FromType, IncompatibleObjC)) { 1311 // Pointer conversions (C++ 4.10). 1312 SCS.Second = ICK_Pointer_Conversion; 1313 SCS.IncompatibleObjC = IncompatibleObjC; 1314 FromType = FromType.getUnqualifiedType(); 1315 } else if (S.IsMemberPointerConversion(From, FromType, ToType, 1316 InOverloadResolution, FromType)) { 1317 // Pointer to member conversions (4.11). 1318 SCS.Second = ICK_Pointer_Member; 1319 } else if (IsVectorConversion(S.Context, FromType, ToType, SecondICK)) { 1320 SCS.Second = SecondICK; 1321 FromType = ToType.getUnqualifiedType(); 1322 } else if (!S.getLangOptions().CPlusPlus && 1323 S.Context.typesAreCompatible(ToType, FromType)) { 1324 // Compatible conversions (Clang extension for C function overloading) 1325 SCS.Second = ICK_Compatible_Conversion; 1326 FromType = ToType.getUnqualifiedType(); 1327 } else if (S.IsNoReturnConversion(FromType, ToType, FromType)) { 1328 // Treat a conversion that strips "noreturn" as an identity conversion. 1329 SCS.Second = ICK_NoReturn_Adjustment; 1330 } else if (IsTransparentUnionStandardConversion(S, From, ToType, 1331 InOverloadResolution, 1332 SCS, CStyle)) { 1333 SCS.Second = ICK_TransparentUnionConversion; 1334 FromType = ToType; 1335 } else { 1336 // No second conversion required. 1337 SCS.Second = ICK_Identity; 1338 } 1339 SCS.setToType(1, FromType); 1340 1341 QualType CanonFrom; 1342 QualType CanonTo; 1343 // The third conversion can be a qualification conversion (C++ 4p1). 1344 bool ObjCLifetimeConversion; 1345 if (S.IsQualificationConversion(FromType, ToType, CStyle, 1346 ObjCLifetimeConversion)) { 1347 SCS.Third = ICK_Qualification; 1348 SCS.QualificationIncludesObjCLifetime = ObjCLifetimeConversion; 1349 FromType = ToType; 1350 CanonFrom = S.Context.getCanonicalType(FromType); 1351 CanonTo = S.Context.getCanonicalType(ToType); 1352 } else { 1353 // No conversion required 1354 SCS.Third = ICK_Identity; 1355 1356 // C++ [over.best.ics]p6: 1357 // [...] Any difference in top-level cv-qualification is 1358 // subsumed by the initialization itself and does not constitute 1359 // a conversion. [...] 1360 CanonFrom = S.Context.getCanonicalType(FromType); 1361 CanonTo = S.Context.getCanonicalType(ToType); 1362 if (CanonFrom.getLocalUnqualifiedType() 1363 == CanonTo.getLocalUnqualifiedType() && 1364 (CanonFrom.getLocalCVRQualifiers() != CanonTo.getLocalCVRQualifiers() 1365 || CanonFrom.getObjCGCAttr() != CanonTo.getObjCGCAttr() 1366 || CanonFrom.getObjCLifetime() != CanonTo.getObjCLifetime())) { 1367 FromType = ToType; 1368 CanonFrom = CanonTo; 1369 } 1370 } 1371 SCS.setToType(2, FromType); 1372 1373 // If we have not converted the argument type to the parameter type, 1374 // this is a bad conversion sequence. 1375 if (CanonFrom != CanonTo) 1376 return false; 1377 1378 return true; 1379} 1380 1381static bool 1382IsTransparentUnionStandardConversion(Sema &S, Expr* From, 1383 QualType &ToType, 1384 bool InOverloadResolution, 1385 StandardConversionSequence &SCS, 1386 bool CStyle) { 1387 1388 const RecordType *UT = ToType->getAsUnionType(); 1389 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 1390 return false; 1391 // The field to initialize within the transparent union. 1392 RecordDecl *UD = UT->getDecl(); 1393 // It's compatible if the expression matches any of the fields. 1394 for (RecordDecl::field_iterator it = UD->field_begin(), 1395 itend = UD->field_end(); 1396 it != itend; ++it) { 1397 if (IsStandardConversion(S, From, it->getType(), InOverloadResolution, SCS, 1398 CStyle, /*ObjCWritebackConversion=*/false)) { 1399 ToType = it->getType(); 1400 return true; 1401 } 1402 } 1403 return false; 1404} 1405 1406/// IsIntegralPromotion - Determines whether the conversion from the 1407/// expression From (whose potentially-adjusted type is FromType) to 1408/// ToType is an integral promotion (C++ 4.5). If so, returns true and 1409/// sets PromotedType to the promoted type. 1410bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) { 1411 const BuiltinType *To = ToType->getAs<BuiltinType>(); 1412 // All integers are built-in. 1413 if (!To) { 1414 return false; 1415 } 1416 1417 // An rvalue of type char, signed char, unsigned char, short int, or 1418 // unsigned short int can be converted to an rvalue of type int if 1419 // int can represent all the values of the source type; otherwise, 1420 // the source rvalue can be converted to an rvalue of type unsigned 1421 // int (C++ 4.5p1). 1422 if (FromType->isPromotableIntegerType() && !FromType->isBooleanType() && 1423 !FromType->isEnumeralType()) { 1424 if (// We can promote any signed, promotable integer type to an int 1425 (FromType->isSignedIntegerType() || 1426 // We can promote any unsigned integer type whose size is 1427 // less than int to an int. 1428 (!FromType->isSignedIntegerType() && 1429 Context.getTypeSize(FromType) < Context.getTypeSize(ToType)))) { 1430 return To->getKind() == BuiltinType::Int; 1431 } 1432 1433 return To->getKind() == BuiltinType::UInt; 1434 } 1435 1436 // C++0x [conv.prom]p3: 1437 // A prvalue of an unscoped enumeration type whose underlying type is not 1438 // fixed (7.2) can be converted to an rvalue a prvalue of the first of the 1439 // following types that can represent all the values of the enumeration 1440 // (i.e., the values in the range bmin to bmax as described in 7.2): int, 1441 // unsigned int, long int, unsigned long int, long long int, or unsigned 1442 // long long int. If none of the types in that list can represent all the 1443 // values of the enumeration, an rvalue a prvalue of an unscoped enumeration 1444 // type can be converted to an rvalue a prvalue of the extended integer type 1445 // with lowest integer conversion rank (4.13) greater than the rank of long 1446 // long in which all the values of the enumeration can be represented. If 1447 // there are two such extended types, the signed one is chosen. 1448 if (const EnumType *FromEnumType = FromType->getAs<EnumType>()) { 1449 // C++0x 7.2p9: Note that this implicit enum to int conversion is not 1450 // provided for a scoped enumeration. 1451 if (FromEnumType->getDecl()->isScoped()) 1452 return false; 1453 1454 // We have already pre-calculated the promotion type, so this is trivial. 1455 if (ToType->isIntegerType() && 1456 !RequireCompleteType(From->getLocStart(), FromType, PDiag())) 1457 return Context.hasSameUnqualifiedType(ToType, 1458 FromEnumType->getDecl()->getPromotionType()); 1459 } 1460 1461 // C++0x [conv.prom]p2: 1462 // A prvalue of type char16_t, char32_t, or wchar_t (3.9.1) can be converted 1463 // to an rvalue a prvalue of the first of the following types that can 1464 // represent all the values of its underlying type: int, unsigned int, 1465 // long int, unsigned long int, long long int, or unsigned long long int. 1466 // If none of the types in that list can represent all the values of its 1467 // underlying type, an rvalue a prvalue of type char16_t, char32_t, 1468 // or wchar_t can be converted to an rvalue a prvalue of its underlying 1469 // type. 1470 if (FromType->isAnyCharacterType() && !FromType->isCharType() && 1471 ToType->isIntegerType()) { 1472 // Determine whether the type we're converting from is signed or 1473 // unsigned. 1474 bool FromIsSigned = FromType->isSignedIntegerType(); 1475 uint64_t FromSize = Context.getTypeSize(FromType); 1476 1477 // The types we'll try to promote to, in the appropriate 1478 // order. Try each of these types. 1479 QualType PromoteTypes[6] = { 1480 Context.IntTy, Context.UnsignedIntTy, 1481 Context.LongTy, Context.UnsignedLongTy , 1482 Context.LongLongTy, Context.UnsignedLongLongTy 1483 }; 1484 for (int Idx = 0; Idx < 6; ++Idx) { 1485 uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]); 1486 if (FromSize < ToSize || 1487 (FromSize == ToSize && 1488 FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) { 1489 // We found the type that we can promote to. If this is the 1490 // type we wanted, we have a promotion. Otherwise, no 1491 // promotion. 1492 return Context.hasSameUnqualifiedType(ToType, PromoteTypes[Idx]); 1493 } 1494 } 1495 } 1496 1497 // An rvalue for an integral bit-field (9.6) can be converted to an 1498 // rvalue of type int if int can represent all the values of the 1499 // bit-field; otherwise, it can be converted to unsigned int if 1500 // unsigned int can represent all the values of the bit-field. If 1501 // the bit-field is larger yet, no integral promotion applies to 1502 // it. If the bit-field has an enumerated type, it is treated as any 1503 // other value of that type for promotion purposes (C++ 4.5p3). 1504 // FIXME: We should delay checking of bit-fields until we actually perform the 1505 // conversion. 1506 using llvm::APSInt; 1507 if (From) 1508 if (FieldDecl *MemberDecl = From->getBitField()) { 1509 APSInt BitWidth; 1510 if (FromType->isIntegralType(Context) && 1511 MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) { 1512 APSInt ToSize(BitWidth.getBitWidth(), BitWidth.isUnsigned()); 1513 ToSize = Context.getTypeSize(ToType); 1514 1515 // Are we promoting to an int from a bitfield that fits in an int? 1516 if (BitWidth < ToSize || 1517 (FromType->isSignedIntegerType() && BitWidth <= ToSize)) { 1518 return To->getKind() == BuiltinType::Int; 1519 } 1520 1521 // Are we promoting to an unsigned int from an unsigned bitfield 1522 // that fits into an unsigned int? 1523 if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize) { 1524 return To->getKind() == BuiltinType::UInt; 1525 } 1526 1527 return false; 1528 } 1529 } 1530 1531 // An rvalue of type bool can be converted to an rvalue of type int, 1532 // with false becoming zero and true becoming one (C++ 4.5p4). 1533 if (FromType->isBooleanType() && To->getKind() == BuiltinType::Int) { 1534 return true; 1535 } 1536 1537 return false; 1538} 1539 1540/// IsFloatingPointPromotion - Determines whether the conversion from 1541/// FromType to ToType is a floating point promotion (C++ 4.6). If so, 1542/// returns true and sets PromotedType to the promoted type. 1543bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType) { 1544 if (const BuiltinType *FromBuiltin = FromType->getAs<BuiltinType>()) 1545 if (const BuiltinType *ToBuiltin = ToType->getAs<BuiltinType>()) { 1546 /// An rvalue of type float can be converted to an rvalue of type 1547 /// double. (C++ 4.6p1). 1548 if (FromBuiltin->getKind() == BuiltinType::Float && 1549 ToBuiltin->getKind() == BuiltinType::Double) 1550 return true; 1551 1552 // C99 6.3.1.5p1: 1553 // When a float is promoted to double or long double, or a 1554 // double is promoted to long double [...]. 1555 if (!getLangOptions().CPlusPlus && 1556 (FromBuiltin->getKind() == BuiltinType::Float || 1557 FromBuiltin->getKind() == BuiltinType::Double) && 1558 (ToBuiltin->getKind() == BuiltinType::LongDouble)) 1559 return true; 1560 1561 // Half can be promoted to float. 1562 if (FromBuiltin->getKind() == BuiltinType::Half && 1563 ToBuiltin->getKind() == BuiltinType::Float) 1564 return true; 1565 } 1566 1567 return false; 1568} 1569 1570/// \brief Determine if a conversion is a complex promotion. 1571/// 1572/// A complex promotion is defined as a complex -> complex conversion 1573/// where the conversion between the underlying real types is a 1574/// floating-point or integral promotion. 1575bool Sema::IsComplexPromotion(QualType FromType, QualType ToType) { 1576 const ComplexType *FromComplex = FromType->getAs<ComplexType>(); 1577 if (!FromComplex) 1578 return false; 1579 1580 const ComplexType *ToComplex = ToType->getAs<ComplexType>(); 1581 if (!ToComplex) 1582 return false; 1583 1584 return IsFloatingPointPromotion(FromComplex->getElementType(), 1585 ToComplex->getElementType()) || 1586 IsIntegralPromotion(0, FromComplex->getElementType(), 1587 ToComplex->getElementType()); 1588} 1589 1590/// BuildSimilarlyQualifiedPointerType - In a pointer conversion from 1591/// the pointer type FromPtr to a pointer to type ToPointee, with the 1592/// same type qualifiers as FromPtr has on its pointee type. ToType, 1593/// if non-empty, will be a pointer to ToType that may or may not have 1594/// the right set of qualifiers on its pointee. 1595/// 1596static QualType 1597BuildSimilarlyQualifiedPointerType(const Type *FromPtr, 1598 QualType ToPointee, QualType ToType, 1599 ASTContext &Context, 1600 bool StripObjCLifetime = false) { 1601 assert((FromPtr->getTypeClass() == Type::Pointer || 1602 FromPtr->getTypeClass() == Type::ObjCObjectPointer) && 1603 "Invalid similarly-qualified pointer type"); 1604 1605 /// Conversions to 'id' subsume cv-qualifier conversions. 1606 if (ToType->isObjCIdType() || ToType->isObjCQualifiedIdType()) 1607 return ToType.getUnqualifiedType(); 1608 1609 QualType CanonFromPointee 1610 = Context.getCanonicalType(FromPtr->getPointeeType()); 1611 QualType CanonToPointee = Context.getCanonicalType(ToPointee); 1612 Qualifiers Quals = CanonFromPointee.getQualifiers(); 1613 1614 if (StripObjCLifetime) 1615 Quals.removeObjCLifetime(); 1616 1617 // Exact qualifier match -> return the pointer type we're converting to. 1618 if (CanonToPointee.getLocalQualifiers() == Quals) { 1619 // ToType is exactly what we need. Return it. 1620 if (!ToType.isNull()) 1621 return ToType.getUnqualifiedType(); 1622 1623 // Build a pointer to ToPointee. It has the right qualifiers 1624 // already. 1625 if (isa<ObjCObjectPointerType>(ToType)) 1626 return Context.getObjCObjectPointerType(ToPointee); 1627 return Context.getPointerType(ToPointee); 1628 } 1629 1630 // Just build a canonical type that has the right qualifiers. 1631 QualType QualifiedCanonToPointee 1632 = Context.getQualifiedType(CanonToPointee.getLocalUnqualifiedType(), Quals); 1633 1634 if (isa<ObjCObjectPointerType>(ToType)) 1635 return Context.getObjCObjectPointerType(QualifiedCanonToPointee); 1636 return Context.getPointerType(QualifiedCanonToPointee); 1637} 1638 1639static bool isNullPointerConstantForConversion(Expr *Expr, 1640 bool InOverloadResolution, 1641 ASTContext &Context) { 1642 // Handle value-dependent integral null pointer constants correctly. 1643 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903 1644 if (Expr->isValueDependent() && !Expr->isTypeDependent() && 1645 Expr->getType()->isIntegerType() && !Expr->getType()->isEnumeralType()) 1646 return !InOverloadResolution; 1647 1648 return Expr->isNullPointerConstant(Context, 1649 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 1650 : Expr::NPC_ValueDependentIsNull); 1651} 1652 1653/// IsPointerConversion - Determines whether the conversion of the 1654/// expression From, which has the (possibly adjusted) type FromType, 1655/// can be converted to the type ToType via a pointer conversion (C++ 1656/// 4.10). If so, returns true and places the converted type (that 1657/// might differ from ToType in its cv-qualifiers at some level) into 1658/// ConvertedType. 1659/// 1660/// This routine also supports conversions to and from block pointers 1661/// and conversions with Objective-C's 'id', 'id<protocols...>', and 1662/// pointers to interfaces. FIXME: Once we've determined the 1663/// appropriate overloading rules for Objective-C, we may want to 1664/// split the Objective-C checks into a different routine; however, 1665/// GCC seems to consider all of these conversions to be pointer 1666/// conversions, so for now they live here. IncompatibleObjC will be 1667/// set if the conversion is an allowed Objective-C conversion that 1668/// should result in a warning. 1669bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType, 1670 bool InOverloadResolution, 1671 QualType& ConvertedType, 1672 bool &IncompatibleObjC) { 1673 IncompatibleObjC = false; 1674 if (isObjCPointerConversion(FromType, ToType, ConvertedType, 1675 IncompatibleObjC)) 1676 return true; 1677 1678 // Conversion from a null pointer constant to any Objective-C pointer type. 1679 if (ToType->isObjCObjectPointerType() && 1680 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1681 ConvertedType = ToType; 1682 return true; 1683 } 1684 1685 // Blocks: Block pointers can be converted to void*. 1686 if (FromType->isBlockPointerType() && ToType->isPointerType() && 1687 ToType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 1688 ConvertedType = ToType; 1689 return true; 1690 } 1691 // Blocks: A null pointer constant can be converted to a block 1692 // pointer type. 1693 if (ToType->isBlockPointerType() && 1694 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1695 ConvertedType = ToType; 1696 return true; 1697 } 1698 1699 // If the left-hand-side is nullptr_t, the right side can be a null 1700 // pointer constant. 1701 if (ToType->isNullPtrType() && 1702 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1703 ConvertedType = ToType; 1704 return true; 1705 } 1706 1707 const PointerType* ToTypePtr = ToType->getAs<PointerType>(); 1708 if (!ToTypePtr) 1709 return false; 1710 1711 // A null pointer constant can be converted to a pointer type (C++ 4.10p1). 1712 if (isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1713 ConvertedType = ToType; 1714 return true; 1715 } 1716 1717 // Beyond this point, both types need to be pointers 1718 // , including objective-c pointers. 1719 QualType ToPointeeType = ToTypePtr->getPointeeType(); 1720 if (FromType->isObjCObjectPointerType() && ToPointeeType->isVoidType() && 1721 !getLangOptions().ObjCAutoRefCount) { 1722 ConvertedType = BuildSimilarlyQualifiedPointerType( 1723 FromType->getAs<ObjCObjectPointerType>(), 1724 ToPointeeType, 1725 ToType, Context); 1726 return true; 1727 } 1728 const PointerType *FromTypePtr = FromType->getAs<PointerType>(); 1729 if (!FromTypePtr) 1730 return false; 1731 1732 QualType FromPointeeType = FromTypePtr->getPointeeType(); 1733 1734 // If the unqualified pointee types are the same, this can't be a 1735 // pointer conversion, so don't do all of the work below. 1736 if (Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) 1737 return false; 1738 1739 // An rvalue of type "pointer to cv T," where T is an object type, 1740 // can be converted to an rvalue of type "pointer to cv void" (C++ 1741 // 4.10p2). 1742 if (FromPointeeType->isIncompleteOrObjectType() && 1743 ToPointeeType->isVoidType()) { 1744 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1745 ToPointeeType, 1746 ToType, Context, 1747 /*StripObjCLifetime=*/true); 1748 return true; 1749 } 1750 1751 // MSVC allows implicit function to void* type conversion. 1752 if (getLangOptions().MicrosoftExt && FromPointeeType->isFunctionType() && 1753 ToPointeeType->isVoidType()) { 1754 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1755 ToPointeeType, 1756 ToType, Context); 1757 return true; 1758 } 1759 1760 // When we're overloading in C, we allow a special kind of pointer 1761 // conversion for compatible-but-not-identical pointee types. 1762 if (!getLangOptions().CPlusPlus && 1763 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) { 1764 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1765 ToPointeeType, 1766 ToType, Context); 1767 return true; 1768 } 1769 1770 // C++ [conv.ptr]p3: 1771 // 1772 // An rvalue of type "pointer to cv D," where D is a class type, 1773 // can be converted to an rvalue of type "pointer to cv B," where 1774 // B is a base class (clause 10) of D. If B is an inaccessible 1775 // (clause 11) or ambiguous (10.2) base class of D, a program that 1776 // necessitates this conversion is ill-formed. The result of the 1777 // conversion is a pointer to the base class sub-object of the 1778 // derived class object. The null pointer value is converted to 1779 // the null pointer value of the destination type. 1780 // 1781 // Note that we do not check for ambiguity or inaccessibility 1782 // here. That is handled by CheckPointerConversion. 1783 if (getLangOptions().CPlusPlus && 1784 FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 1785 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType) && 1786 !RequireCompleteType(From->getLocStart(), FromPointeeType, PDiag()) && 1787 IsDerivedFrom(FromPointeeType, ToPointeeType)) { 1788 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1789 ToPointeeType, 1790 ToType, Context); 1791 return true; 1792 } 1793 1794 if (FromPointeeType->isVectorType() && ToPointeeType->isVectorType() && 1795 Context.areCompatibleVectorTypes(FromPointeeType, ToPointeeType)) { 1796 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1797 ToPointeeType, 1798 ToType, Context); 1799 return true; 1800 } 1801 1802 return false; 1803} 1804 1805/// \brief Adopt the given qualifiers for the given type. 1806static QualType AdoptQualifiers(ASTContext &Context, QualType T, Qualifiers Qs){ 1807 Qualifiers TQs = T.getQualifiers(); 1808 1809 // Check whether qualifiers already match. 1810 if (TQs == Qs) 1811 return T; 1812 1813 if (Qs.compatiblyIncludes(TQs)) 1814 return Context.getQualifiedType(T, Qs); 1815 1816 return Context.getQualifiedType(T.getUnqualifiedType(), Qs); 1817} 1818 1819/// isObjCPointerConversion - Determines whether this is an 1820/// Objective-C pointer conversion. Subroutine of IsPointerConversion, 1821/// with the same arguments and return values. 1822bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType, 1823 QualType& ConvertedType, 1824 bool &IncompatibleObjC) { 1825 if (!getLangOptions().ObjC1) 1826 return false; 1827 1828 // The set of qualifiers on the type we're converting from. 1829 Qualifiers FromQualifiers = FromType.getQualifiers(); 1830 1831 // First, we handle all conversions on ObjC object pointer types. 1832 const ObjCObjectPointerType* ToObjCPtr = 1833 ToType->getAs<ObjCObjectPointerType>(); 1834 const ObjCObjectPointerType *FromObjCPtr = 1835 FromType->getAs<ObjCObjectPointerType>(); 1836 1837 if (ToObjCPtr && FromObjCPtr) { 1838 // If the pointee types are the same (ignoring qualifications), 1839 // then this is not a pointer conversion. 1840 if (Context.hasSameUnqualifiedType(ToObjCPtr->getPointeeType(), 1841 FromObjCPtr->getPointeeType())) 1842 return false; 1843 1844 // Check for compatible 1845 // Objective C++: We're able to convert between "id" or "Class" and a 1846 // pointer to any interface (in both directions). 1847 if (ToObjCPtr->isObjCBuiltinType() && FromObjCPtr->isObjCBuiltinType()) { 1848 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1849 return true; 1850 } 1851 // Conversions with Objective-C's id<...>. 1852 if ((FromObjCPtr->isObjCQualifiedIdType() || 1853 ToObjCPtr->isObjCQualifiedIdType()) && 1854 Context.ObjCQualifiedIdTypesAreCompatible(ToType, FromType, 1855 /*compare=*/false)) { 1856 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1857 return true; 1858 } 1859 // Objective C++: We're able to convert from a pointer to an 1860 // interface to a pointer to a different interface. 1861 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) { 1862 const ObjCInterfaceType* LHS = ToObjCPtr->getInterfaceType(); 1863 const ObjCInterfaceType* RHS = FromObjCPtr->getInterfaceType(); 1864 if (getLangOptions().CPlusPlus && LHS && RHS && 1865 !ToObjCPtr->getPointeeType().isAtLeastAsQualifiedAs( 1866 FromObjCPtr->getPointeeType())) 1867 return false; 1868 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1869 ToObjCPtr->getPointeeType(), 1870 ToType, Context); 1871 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1872 return true; 1873 } 1874 1875 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) { 1876 // Okay: this is some kind of implicit downcast of Objective-C 1877 // interfaces, which is permitted. However, we're going to 1878 // complain about it. 1879 IncompatibleObjC = true; 1880 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1881 ToObjCPtr->getPointeeType(), 1882 ToType, Context); 1883 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1884 return true; 1885 } 1886 } 1887 // Beyond this point, both types need to be C pointers or block pointers. 1888 QualType ToPointeeType; 1889 if (const PointerType *ToCPtr = ToType->getAs<PointerType>()) 1890 ToPointeeType = ToCPtr->getPointeeType(); 1891 else if (const BlockPointerType *ToBlockPtr = 1892 ToType->getAs<BlockPointerType>()) { 1893 // Objective C++: We're able to convert from a pointer to any object 1894 // to a block pointer type. 1895 if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) { 1896 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1897 return true; 1898 } 1899 ToPointeeType = ToBlockPtr->getPointeeType(); 1900 } 1901 else if (FromType->getAs<BlockPointerType>() && 1902 ToObjCPtr && ToObjCPtr->isObjCBuiltinType()) { 1903 // Objective C++: We're able to convert from a block pointer type to a 1904 // pointer to any object. 1905 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1906 return true; 1907 } 1908 else 1909 return false; 1910 1911 QualType FromPointeeType; 1912 if (const PointerType *FromCPtr = FromType->getAs<PointerType>()) 1913 FromPointeeType = FromCPtr->getPointeeType(); 1914 else if (const BlockPointerType *FromBlockPtr = 1915 FromType->getAs<BlockPointerType>()) 1916 FromPointeeType = FromBlockPtr->getPointeeType(); 1917 else 1918 return false; 1919 1920 // If we have pointers to pointers, recursively check whether this 1921 // is an Objective-C conversion. 1922 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() && 1923 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1924 IncompatibleObjC)) { 1925 // We always complain about this conversion. 1926 IncompatibleObjC = true; 1927 ConvertedType = Context.getPointerType(ConvertedType); 1928 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1929 return true; 1930 } 1931 // Allow conversion of pointee being objective-c pointer to another one; 1932 // as in I* to id. 1933 if (FromPointeeType->getAs<ObjCObjectPointerType>() && 1934 ToPointeeType->getAs<ObjCObjectPointerType>() && 1935 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1936 IncompatibleObjC)) { 1937 1938 ConvertedType = Context.getPointerType(ConvertedType); 1939 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1940 return true; 1941 } 1942 1943 // If we have pointers to functions or blocks, check whether the only 1944 // differences in the argument and result types are in Objective-C 1945 // pointer conversions. If so, we permit the conversion (but 1946 // complain about it). 1947 const FunctionProtoType *FromFunctionType 1948 = FromPointeeType->getAs<FunctionProtoType>(); 1949 const FunctionProtoType *ToFunctionType 1950 = ToPointeeType->getAs<FunctionProtoType>(); 1951 if (FromFunctionType && ToFunctionType) { 1952 // If the function types are exactly the same, this isn't an 1953 // Objective-C pointer conversion. 1954 if (Context.getCanonicalType(FromPointeeType) 1955 == Context.getCanonicalType(ToPointeeType)) 1956 return false; 1957 1958 // Perform the quick checks that will tell us whether these 1959 // function types are obviously different. 1960 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 1961 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() || 1962 FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals()) 1963 return false; 1964 1965 bool HasObjCConversion = false; 1966 if (Context.getCanonicalType(FromFunctionType->getResultType()) 1967 == Context.getCanonicalType(ToFunctionType->getResultType())) { 1968 // Okay, the types match exactly. Nothing to do. 1969 } else if (isObjCPointerConversion(FromFunctionType->getResultType(), 1970 ToFunctionType->getResultType(), 1971 ConvertedType, IncompatibleObjC)) { 1972 // Okay, we have an Objective-C pointer conversion. 1973 HasObjCConversion = true; 1974 } else { 1975 // Function types are too different. Abort. 1976 return false; 1977 } 1978 1979 // Check argument types. 1980 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 1981 ArgIdx != NumArgs; ++ArgIdx) { 1982 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 1983 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 1984 if (Context.getCanonicalType(FromArgType) 1985 == Context.getCanonicalType(ToArgType)) { 1986 // Okay, the types match exactly. Nothing to do. 1987 } else if (isObjCPointerConversion(FromArgType, ToArgType, 1988 ConvertedType, IncompatibleObjC)) { 1989 // Okay, we have an Objective-C pointer conversion. 1990 HasObjCConversion = true; 1991 } else { 1992 // Argument types are too different. Abort. 1993 return false; 1994 } 1995 } 1996 1997 if (HasObjCConversion) { 1998 // We had an Objective-C conversion. Allow this pointer 1999 // conversion, but complain about it. 2000 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 2001 IncompatibleObjC = true; 2002 return true; 2003 } 2004 } 2005 2006 return false; 2007} 2008 2009/// \brief Determine whether this is an Objective-C writeback conversion, 2010/// used for parameter passing when performing automatic reference counting. 2011/// 2012/// \param FromType The type we're converting form. 2013/// 2014/// \param ToType The type we're converting to. 2015/// 2016/// \param ConvertedType The type that will be produced after applying 2017/// this conversion. 2018bool Sema::isObjCWritebackConversion(QualType FromType, QualType ToType, 2019 QualType &ConvertedType) { 2020 if (!getLangOptions().ObjCAutoRefCount || 2021 Context.hasSameUnqualifiedType(FromType, ToType)) 2022 return false; 2023 2024 // Parameter must be a pointer to __autoreleasing (with no other qualifiers). 2025 QualType ToPointee; 2026 if (const PointerType *ToPointer = ToType->getAs<PointerType>()) 2027 ToPointee = ToPointer->getPointeeType(); 2028 else 2029 return false; 2030 2031 Qualifiers ToQuals = ToPointee.getQualifiers(); 2032 if (!ToPointee->isObjCLifetimeType() || 2033 ToQuals.getObjCLifetime() != Qualifiers::OCL_Autoreleasing || 2034 !ToQuals.withoutObjCGLifetime().empty()) 2035 return false; 2036 2037 // Argument must be a pointer to __strong to __weak. 2038 QualType FromPointee; 2039 if (const PointerType *FromPointer = FromType->getAs<PointerType>()) 2040 FromPointee = FromPointer->getPointeeType(); 2041 else 2042 return false; 2043 2044 Qualifiers FromQuals = FromPointee.getQualifiers(); 2045 if (!FromPointee->isObjCLifetimeType() || 2046 (FromQuals.getObjCLifetime() != Qualifiers::OCL_Strong && 2047 FromQuals.getObjCLifetime() != Qualifiers::OCL_Weak)) 2048 return false; 2049 2050 // Make sure that we have compatible qualifiers. 2051 FromQuals.setObjCLifetime(Qualifiers::OCL_Autoreleasing); 2052 if (!ToQuals.compatiblyIncludes(FromQuals)) 2053 return false; 2054 2055 // Remove qualifiers from the pointee type we're converting from; they 2056 // aren't used in the compatibility check belong, and we'll be adding back 2057 // qualifiers (with __autoreleasing) if the compatibility check succeeds. 2058 FromPointee = FromPointee.getUnqualifiedType(); 2059 2060 // The unqualified form of the pointee types must be compatible. 2061 ToPointee = ToPointee.getUnqualifiedType(); 2062 bool IncompatibleObjC; 2063 if (Context.typesAreCompatible(FromPointee, ToPointee)) 2064 FromPointee = ToPointee; 2065 else if (!isObjCPointerConversion(FromPointee, ToPointee, FromPointee, 2066 IncompatibleObjC)) 2067 return false; 2068 2069 /// \brief Construct the type we're converting to, which is a pointer to 2070 /// __autoreleasing pointee. 2071 FromPointee = Context.getQualifiedType(FromPointee, FromQuals); 2072 ConvertedType = Context.getPointerType(FromPointee); 2073 return true; 2074} 2075 2076bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType, 2077 QualType& ConvertedType) { 2078 QualType ToPointeeType; 2079 if (const BlockPointerType *ToBlockPtr = 2080 ToType->getAs<BlockPointerType>()) 2081 ToPointeeType = ToBlockPtr->getPointeeType(); 2082 else 2083 return false; 2084 2085 QualType FromPointeeType; 2086 if (const BlockPointerType *FromBlockPtr = 2087 FromType->getAs<BlockPointerType>()) 2088 FromPointeeType = FromBlockPtr->getPointeeType(); 2089 else 2090 return false; 2091 // We have pointer to blocks, check whether the only 2092 // differences in the argument and result types are in Objective-C 2093 // pointer conversions. If so, we permit the conversion. 2094 2095 const FunctionProtoType *FromFunctionType 2096 = FromPointeeType->getAs<FunctionProtoType>(); 2097 const FunctionProtoType *ToFunctionType 2098 = ToPointeeType->getAs<FunctionProtoType>(); 2099 2100 if (!FromFunctionType || !ToFunctionType) 2101 return false; 2102 2103 if (Context.hasSameType(FromPointeeType, ToPointeeType)) 2104 return true; 2105 2106 // Perform the quick checks that will tell us whether these 2107 // function types are obviously different. 2108 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 2109 FromFunctionType->isVariadic() != ToFunctionType->isVariadic()) 2110 return false; 2111 2112 FunctionType::ExtInfo FromEInfo = FromFunctionType->getExtInfo(); 2113 FunctionType::ExtInfo ToEInfo = ToFunctionType->getExtInfo(); 2114 if (FromEInfo != ToEInfo) 2115 return false; 2116 2117 bool IncompatibleObjC = false; 2118 if (Context.hasSameType(FromFunctionType->getResultType(), 2119 ToFunctionType->getResultType())) { 2120 // Okay, the types match exactly. Nothing to do. 2121 } else { 2122 QualType RHS = FromFunctionType->getResultType(); 2123 QualType LHS = ToFunctionType->getResultType(); 2124 if ((!getLangOptions().CPlusPlus || !RHS->isRecordType()) && 2125 !RHS.hasQualifiers() && LHS.hasQualifiers()) 2126 LHS = LHS.getUnqualifiedType(); 2127 2128 if (Context.hasSameType(RHS,LHS)) { 2129 // OK exact match. 2130 } else if (isObjCPointerConversion(RHS, LHS, 2131 ConvertedType, IncompatibleObjC)) { 2132 if (IncompatibleObjC) 2133 return false; 2134 // Okay, we have an Objective-C pointer conversion. 2135 } 2136 else 2137 return false; 2138 } 2139 2140 // Check argument types. 2141 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 2142 ArgIdx != NumArgs; ++ArgIdx) { 2143 IncompatibleObjC = false; 2144 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 2145 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 2146 if (Context.hasSameType(FromArgType, ToArgType)) { 2147 // Okay, the types match exactly. Nothing to do. 2148 } else if (isObjCPointerConversion(ToArgType, FromArgType, 2149 ConvertedType, IncompatibleObjC)) { 2150 if (IncompatibleObjC) 2151 return false; 2152 // Okay, we have an Objective-C pointer conversion. 2153 } else 2154 // Argument types are too different. Abort. 2155 return false; 2156 } 2157 if (LangOpts.ObjCAutoRefCount && 2158 !Context.FunctionTypesMatchOnNSConsumedAttrs(FromFunctionType, 2159 ToFunctionType)) 2160 return false; 2161 2162 ConvertedType = ToType; 2163 return true; 2164} 2165 2166enum { 2167 ft_default, 2168 ft_different_class, 2169 ft_parameter_arity, 2170 ft_parameter_mismatch, 2171 ft_return_type, 2172 ft_qualifer_mismatch 2173}; 2174 2175/// HandleFunctionTypeMismatch - Gives diagnostic information for differeing 2176/// function types. Catches different number of parameter, mismatch in 2177/// parameter types, and different return types. 2178void Sema::HandleFunctionTypeMismatch(PartialDiagnostic &PDiag, 2179 QualType FromType, QualType ToType) { 2180 // Get the function type from the pointers. 2181 if (FromType->isMemberPointerType() && ToType->isMemberPointerType()) { 2182 const MemberPointerType *FromMember = FromType->getAs<MemberPointerType>(), 2183 *ToMember = ToType->getAs<MemberPointerType>(); 2184 if (FromMember->getClass() != ToMember->getClass()) { 2185 PDiag << ft_different_class << QualType(ToMember->getClass(), 0) 2186 << QualType(FromMember->getClass(), 0); 2187 return; 2188 } 2189 FromType = FromMember->getPointeeType(); 2190 ToType = ToMember->getPointeeType(); 2191 } else if (FromType->isPointerType() && ToType->isPointerType()) { 2192 FromType = FromType->getPointeeType(); 2193 ToType = ToType->getPointeeType(); 2194 } else { 2195 PDiag << ft_default; 2196 return; 2197 } 2198 2199 FromType = FromType.getNonReferenceType(); 2200 ToType = ToType.getNonReferenceType(); 2201 2202 // If either type is not valid, of the types are the same, no extra info. 2203 if (FromType.isNull() || ToType.isNull() || 2204 Context.hasSameType(FromType, ToType)) { 2205 PDiag << ft_default; 2206 return; 2207 } 2208 2209 // Don't print extra info for non-specialized template functions. 2210 if (FromType->isInstantiationDependentType() && 2211 !FromType->getAs<TemplateSpecializationType>()) { 2212 PDiag << ft_default; 2213 return; 2214 } 2215 2216 const FunctionProtoType *FromFunction = FromType->getAs<FunctionProtoType>(), 2217 *ToFunction = ToType->getAs<FunctionProtoType>(); 2218 2219 // Both types need to be function types. 2220 if (!FromFunction || !ToFunction) { 2221 PDiag << ft_default; 2222 return; 2223 } 2224 2225 if (FromFunction->getNumArgs() != ToFunction->getNumArgs()) { 2226 PDiag << ft_parameter_arity << ToFunction->getNumArgs() 2227 << FromFunction->getNumArgs(); 2228 return; 2229 } 2230 2231 // Handle different parameter types. 2232 unsigned ArgPos; 2233 if (!FunctionArgTypesAreEqual(FromFunction, ToFunction, &ArgPos)) { 2234 PDiag << ft_parameter_mismatch << ArgPos + 1 2235 << ToFunction->getArgType(ArgPos) 2236 << FromFunction->getArgType(ArgPos); 2237 return; 2238 } 2239 2240 // Handle different return type. 2241 if (!Context.hasSameType(FromFunction->getResultType(), 2242 ToFunction->getResultType())) { 2243 PDiag << ft_return_type << ToFunction->getResultType() 2244 << FromFunction->getResultType(); 2245 return; 2246 } 2247 2248 unsigned FromQuals = FromFunction->getTypeQuals(), 2249 ToQuals = ToFunction->getTypeQuals(); 2250 if (FromQuals != ToQuals) { 2251 PDiag << ft_qualifer_mismatch << ToQuals << FromQuals; 2252 return; 2253 } 2254 2255 // Unable to find a difference, so add no extra info. 2256 PDiag << ft_default; 2257} 2258 2259/// FunctionArgTypesAreEqual - This routine checks two function proto types 2260/// for equlity of their argument types. Caller has already checked that 2261/// they have same number of arguments. This routine assumes that Objective-C 2262/// pointer types which only differ in their protocol qualifiers are equal. 2263/// If the parameters are different, ArgPos will have the the parameter index 2264/// of the first different parameter. 2265bool Sema::FunctionArgTypesAreEqual(const FunctionProtoType *OldType, 2266 const FunctionProtoType *NewType, 2267 unsigned *ArgPos) { 2268 if (!getLangOptions().ObjC1) { 2269 for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(), 2270 N = NewType->arg_type_begin(), 2271 E = OldType->arg_type_end(); O && (O != E); ++O, ++N) { 2272 if (!Context.hasSameType(*O, *N)) { 2273 if (ArgPos) *ArgPos = O - OldType->arg_type_begin(); 2274 return false; 2275 } 2276 } 2277 return true; 2278 } 2279 2280 for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(), 2281 N = NewType->arg_type_begin(), 2282 E = OldType->arg_type_end(); O && (O != E); ++O, ++N) { 2283 QualType ToType = (*O); 2284 QualType FromType = (*N); 2285 if (!Context.hasSameType(ToType, FromType)) { 2286 if (const PointerType *PTTo = ToType->getAs<PointerType>()) { 2287 if (const PointerType *PTFr = FromType->getAs<PointerType>()) 2288 if ((PTTo->getPointeeType()->isObjCQualifiedIdType() && 2289 PTFr->getPointeeType()->isObjCQualifiedIdType()) || 2290 (PTTo->getPointeeType()->isObjCQualifiedClassType() && 2291 PTFr->getPointeeType()->isObjCQualifiedClassType())) 2292 continue; 2293 } 2294 else if (const ObjCObjectPointerType *PTTo = 2295 ToType->getAs<ObjCObjectPointerType>()) { 2296 if (const ObjCObjectPointerType *PTFr = 2297 FromType->getAs<ObjCObjectPointerType>()) 2298 if (PTTo->getInterfaceDecl() == PTFr->getInterfaceDecl()) 2299 continue; 2300 } 2301 if (ArgPos) *ArgPos = O - OldType->arg_type_begin(); 2302 return false; 2303 } 2304 } 2305 return true; 2306} 2307 2308/// CheckPointerConversion - Check the pointer conversion from the 2309/// expression From to the type ToType. This routine checks for 2310/// ambiguous or inaccessible derived-to-base pointer 2311/// conversions for which IsPointerConversion has already returned 2312/// true. It returns true and produces a diagnostic if there was an 2313/// error, or returns false otherwise. 2314bool Sema::CheckPointerConversion(Expr *From, QualType ToType, 2315 CastKind &Kind, 2316 CXXCastPath& BasePath, 2317 bool IgnoreBaseAccess) { 2318 QualType FromType = From->getType(); 2319 bool IsCStyleOrFunctionalCast = IgnoreBaseAccess; 2320 2321 Kind = CK_BitCast; 2322 2323 if (!IsCStyleOrFunctionalCast && 2324 Context.hasSameUnqualifiedType(From->getType(), Context.BoolTy) && 2325 From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 2326 DiagRuntimeBehavior(From->getExprLoc(), From, 2327 PDiag(diag::warn_impcast_bool_to_null_pointer) 2328 << ToType << From->getSourceRange()); 2329 2330 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) { 2331 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) { 2332 QualType FromPointeeType = FromPtrType->getPointeeType(), 2333 ToPointeeType = ToPtrType->getPointeeType(); 2334 2335 if (FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 2336 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) { 2337 // We must have a derived-to-base conversion. Check an 2338 // ambiguous or inaccessible conversion. 2339 if (CheckDerivedToBaseConversion(FromPointeeType, ToPointeeType, 2340 From->getExprLoc(), 2341 From->getSourceRange(), &BasePath, 2342 IgnoreBaseAccess)) 2343 return true; 2344 2345 // The conversion was successful. 2346 Kind = CK_DerivedToBase; 2347 } 2348 } 2349 } else if (const ObjCObjectPointerType *ToPtrType = 2350 ToType->getAs<ObjCObjectPointerType>()) { 2351 if (const ObjCObjectPointerType *FromPtrType = 2352 FromType->getAs<ObjCObjectPointerType>()) { 2353 // Objective-C++ conversions are always okay. 2354 // FIXME: We should have a different class of conversions for the 2355 // Objective-C++ implicit conversions. 2356 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType()) 2357 return false; 2358 } else if (FromType->isBlockPointerType()) { 2359 Kind = CK_BlockPointerToObjCPointerCast; 2360 } else { 2361 Kind = CK_CPointerToObjCPointerCast; 2362 } 2363 } else if (ToType->isBlockPointerType()) { 2364 if (!FromType->isBlockPointerType()) 2365 Kind = CK_AnyPointerToBlockPointerCast; 2366 } 2367 2368 // We shouldn't fall into this case unless it's valid for other 2369 // reasons. 2370 if (From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 2371 Kind = CK_NullToPointer; 2372 2373 return false; 2374} 2375 2376/// IsMemberPointerConversion - Determines whether the conversion of the 2377/// expression From, which has the (possibly adjusted) type FromType, can be 2378/// converted to the type ToType via a member pointer conversion (C++ 4.11). 2379/// If so, returns true and places the converted type (that might differ from 2380/// ToType in its cv-qualifiers at some level) into ConvertedType. 2381bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType, 2382 QualType ToType, 2383 bool InOverloadResolution, 2384 QualType &ConvertedType) { 2385 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>(); 2386 if (!ToTypePtr) 2387 return false; 2388 2389 // A null pointer constant can be converted to a member pointer (C++ 4.11p1) 2390 if (From->isNullPointerConstant(Context, 2391 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 2392 : Expr::NPC_ValueDependentIsNull)) { 2393 ConvertedType = ToType; 2394 return true; 2395 } 2396 2397 // Otherwise, both types have to be member pointers. 2398 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>(); 2399 if (!FromTypePtr) 2400 return false; 2401 2402 // A pointer to member of B can be converted to a pointer to member of D, 2403 // where D is derived from B (C++ 4.11p2). 2404 QualType FromClass(FromTypePtr->getClass(), 0); 2405 QualType ToClass(ToTypePtr->getClass(), 0); 2406 2407 if (!Context.hasSameUnqualifiedType(FromClass, ToClass) && 2408 !RequireCompleteType(From->getLocStart(), ToClass, PDiag()) && 2409 IsDerivedFrom(ToClass, FromClass)) { 2410 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(), 2411 ToClass.getTypePtr()); 2412 return true; 2413 } 2414 2415 return false; 2416} 2417 2418/// CheckMemberPointerConversion - Check the member pointer conversion from the 2419/// expression From to the type ToType. This routine checks for ambiguous or 2420/// virtual or inaccessible base-to-derived member pointer conversions 2421/// for which IsMemberPointerConversion has already returned true. It returns 2422/// true and produces a diagnostic if there was an error, or returns false 2423/// otherwise. 2424bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType, 2425 CastKind &Kind, 2426 CXXCastPath &BasePath, 2427 bool IgnoreBaseAccess) { 2428 QualType FromType = From->getType(); 2429 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>(); 2430 if (!FromPtrType) { 2431 // This must be a null pointer to member pointer conversion 2432 assert(From->isNullPointerConstant(Context, 2433 Expr::NPC_ValueDependentIsNull) && 2434 "Expr must be null pointer constant!"); 2435 Kind = CK_NullToMemberPointer; 2436 return false; 2437 } 2438 2439 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>(); 2440 assert(ToPtrType && "No member pointer cast has a target type " 2441 "that is not a member pointer."); 2442 2443 QualType FromClass = QualType(FromPtrType->getClass(), 0); 2444 QualType ToClass = QualType(ToPtrType->getClass(), 0); 2445 2446 // FIXME: What about dependent types? 2447 assert(FromClass->isRecordType() && "Pointer into non-class."); 2448 assert(ToClass->isRecordType() && "Pointer into non-class."); 2449 2450 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 2451 /*DetectVirtual=*/true); 2452 bool DerivationOkay = IsDerivedFrom(ToClass, FromClass, Paths); 2453 assert(DerivationOkay && 2454 "Should not have been called if derivation isn't OK."); 2455 (void)DerivationOkay; 2456 2457 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass). 2458 getUnqualifiedType())) { 2459 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths); 2460 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv) 2461 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange(); 2462 return true; 2463 } 2464 2465 if (const RecordType *VBase = Paths.getDetectedVirtual()) { 2466 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual) 2467 << FromClass << ToClass << QualType(VBase, 0) 2468 << From->getSourceRange(); 2469 return true; 2470 } 2471 2472 if (!IgnoreBaseAccess) 2473 CheckBaseClassAccess(From->getExprLoc(), FromClass, ToClass, 2474 Paths.front(), 2475 diag::err_downcast_from_inaccessible_base); 2476 2477 // Must be a base to derived member conversion. 2478 BuildBasePathArray(Paths, BasePath); 2479 Kind = CK_BaseToDerivedMemberPointer; 2480 return false; 2481} 2482 2483/// IsQualificationConversion - Determines whether the conversion from 2484/// an rvalue of type FromType to ToType is a qualification conversion 2485/// (C++ 4.4). 2486/// 2487/// \param ObjCLifetimeConversion Output parameter that will be set to indicate 2488/// when the qualification conversion involves a change in the Objective-C 2489/// object lifetime. 2490bool 2491Sema::IsQualificationConversion(QualType FromType, QualType ToType, 2492 bool CStyle, bool &ObjCLifetimeConversion) { 2493 FromType = Context.getCanonicalType(FromType); 2494 ToType = Context.getCanonicalType(ToType); 2495 ObjCLifetimeConversion = false; 2496 2497 // If FromType and ToType are the same type, this is not a 2498 // qualification conversion. 2499 if (FromType.getUnqualifiedType() == ToType.getUnqualifiedType()) 2500 return false; 2501 2502 // (C++ 4.4p4): 2503 // A conversion can add cv-qualifiers at levels other than the first 2504 // in multi-level pointers, subject to the following rules: [...] 2505 bool PreviousToQualsIncludeConst = true; 2506 bool UnwrappedAnyPointer = false; 2507 while (Context.UnwrapSimilarPointerTypes(FromType, ToType)) { 2508 // Within each iteration of the loop, we check the qualifiers to 2509 // determine if this still looks like a qualification 2510 // conversion. Then, if all is well, we unwrap one more level of 2511 // pointers or pointers-to-members and do it all again 2512 // until there are no more pointers or pointers-to-members left to 2513 // unwrap. 2514 UnwrappedAnyPointer = true; 2515 2516 Qualifiers FromQuals = FromType.getQualifiers(); 2517 Qualifiers ToQuals = ToType.getQualifiers(); 2518 2519 // Objective-C ARC: 2520 // Check Objective-C lifetime conversions. 2521 if (FromQuals.getObjCLifetime() != ToQuals.getObjCLifetime() && 2522 UnwrappedAnyPointer) { 2523 if (ToQuals.compatiblyIncludesObjCLifetime(FromQuals)) { 2524 ObjCLifetimeConversion = true; 2525 FromQuals.removeObjCLifetime(); 2526 ToQuals.removeObjCLifetime(); 2527 } else { 2528 // Qualification conversions cannot cast between different 2529 // Objective-C lifetime qualifiers. 2530 return false; 2531 } 2532 } 2533 2534 // Allow addition/removal of GC attributes but not changing GC attributes. 2535 if (FromQuals.getObjCGCAttr() != ToQuals.getObjCGCAttr() && 2536 (!FromQuals.hasObjCGCAttr() || !ToQuals.hasObjCGCAttr())) { 2537 FromQuals.removeObjCGCAttr(); 2538 ToQuals.removeObjCGCAttr(); 2539 } 2540 2541 // -- for every j > 0, if const is in cv 1,j then const is in cv 2542 // 2,j, and similarly for volatile. 2543 if (!CStyle && !ToQuals.compatiblyIncludes(FromQuals)) 2544 return false; 2545 2546 // -- if the cv 1,j and cv 2,j are different, then const is in 2547 // every cv for 0 < k < j. 2548 if (!CStyle && FromQuals.getCVRQualifiers() != ToQuals.getCVRQualifiers() 2549 && !PreviousToQualsIncludeConst) 2550 return false; 2551 2552 // Keep track of whether all prior cv-qualifiers in the "to" type 2553 // include const. 2554 PreviousToQualsIncludeConst 2555 = PreviousToQualsIncludeConst && ToQuals.hasConst(); 2556 } 2557 2558 // We are left with FromType and ToType being the pointee types 2559 // after unwrapping the original FromType and ToType the same number 2560 // of types. If we unwrapped any pointers, and if FromType and 2561 // ToType have the same unqualified type (since we checked 2562 // qualifiers above), then this is a qualification conversion. 2563 return UnwrappedAnyPointer && Context.hasSameUnqualifiedType(FromType,ToType); 2564} 2565 2566/// Determines whether there is a user-defined conversion sequence 2567/// (C++ [over.ics.user]) that converts expression From to the type 2568/// ToType. If such a conversion exists, User will contain the 2569/// user-defined conversion sequence that performs such a conversion 2570/// and this routine will return true. Otherwise, this routine returns 2571/// false and User is unspecified. 2572/// 2573/// \param AllowExplicit true if the conversion should consider C++0x 2574/// "explicit" conversion functions as well as non-explicit conversion 2575/// functions (C++0x [class.conv.fct]p2). 2576static OverloadingResult 2577IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 2578 UserDefinedConversionSequence& User, 2579 OverloadCandidateSet& CandidateSet, 2580 bool AllowExplicit) { 2581 // Whether we will only visit constructors. 2582 bool ConstructorsOnly = false; 2583 2584 // If the type we are conversion to is a class type, enumerate its 2585 // constructors. 2586 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) { 2587 // C++ [over.match.ctor]p1: 2588 // When objects of class type are direct-initialized (8.5), or 2589 // copy-initialized from an expression of the same or a 2590 // derived class type (8.5), overload resolution selects the 2591 // constructor. [...] For copy-initialization, the candidate 2592 // functions are all the converting constructors (12.3.1) of 2593 // that class. The argument list is the expression-list within 2594 // the parentheses of the initializer. 2595 if (S.Context.hasSameUnqualifiedType(ToType, From->getType()) || 2596 (From->getType()->getAs<RecordType>() && 2597 S.IsDerivedFrom(From->getType(), ToType))) 2598 ConstructorsOnly = true; 2599 2600 S.RequireCompleteType(From->getLocStart(), ToType, S.PDiag()); 2601 // RequireCompleteType may have returned true due to some invalid decl 2602 // during template instantiation, but ToType may be complete enough now 2603 // to try to recover. 2604 if (ToType->isIncompleteType()) { 2605 // We're not going to find any constructors. 2606 } else if (CXXRecordDecl *ToRecordDecl 2607 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) { 2608 DeclContext::lookup_iterator Con, ConEnd; 2609 for (llvm::tie(Con, ConEnd) = S.LookupConstructors(ToRecordDecl); 2610 Con != ConEnd; ++Con) { 2611 NamedDecl *D = *Con; 2612 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2613 2614 // Find the constructor (which may be a template). 2615 CXXConstructorDecl *Constructor = 0; 2616 FunctionTemplateDecl *ConstructorTmpl 2617 = dyn_cast<FunctionTemplateDecl>(D); 2618 if (ConstructorTmpl) 2619 Constructor 2620 = cast<CXXConstructorDecl>(ConstructorTmpl->getTemplatedDecl()); 2621 else 2622 Constructor = cast<CXXConstructorDecl>(D); 2623 2624 if (!Constructor->isInvalidDecl() && 2625 Constructor->isConvertingConstructor(AllowExplicit)) { 2626 if (ConstructorTmpl) 2627 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2628 /*ExplicitArgs*/ 0, 2629 &From, 1, CandidateSet, 2630 /*SuppressUserConversions=*/ 2631 !ConstructorsOnly); 2632 else 2633 // Allow one user-defined conversion when user specifies a 2634 // From->ToType conversion via an static cast (c-style, etc). 2635 S.AddOverloadCandidate(Constructor, FoundDecl, 2636 &From, 1, CandidateSet, 2637 /*SuppressUserConversions=*/ 2638 !ConstructorsOnly); 2639 } 2640 } 2641 } 2642 } 2643 2644 // Enumerate conversion functions, if we're allowed to. 2645 if (ConstructorsOnly) { 2646 } else if (S.RequireCompleteType(From->getLocStart(), From->getType(), 2647 S.PDiag(0) << From->getSourceRange())) { 2648 // No conversion functions from incomplete types. 2649 } else if (const RecordType *FromRecordType 2650 = From->getType()->getAs<RecordType>()) { 2651 if (CXXRecordDecl *FromRecordDecl 2652 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) { 2653 // Add all of the conversion functions as candidates. 2654 const UnresolvedSetImpl *Conversions 2655 = FromRecordDecl->getVisibleConversionFunctions(); 2656 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 2657 E = Conversions->end(); I != E; ++I) { 2658 DeclAccessPair FoundDecl = I.getPair(); 2659 NamedDecl *D = FoundDecl.getDecl(); 2660 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 2661 if (isa<UsingShadowDecl>(D)) 2662 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2663 2664 CXXConversionDecl *Conv; 2665 FunctionTemplateDecl *ConvTemplate; 2666 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D))) 2667 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2668 else 2669 Conv = cast<CXXConversionDecl>(D); 2670 2671 if (AllowExplicit || !Conv->isExplicit()) { 2672 if (ConvTemplate) 2673 S.AddTemplateConversionCandidate(ConvTemplate, FoundDecl, 2674 ActingContext, From, ToType, 2675 CandidateSet); 2676 else 2677 S.AddConversionCandidate(Conv, FoundDecl, ActingContext, 2678 From, ToType, CandidateSet); 2679 } 2680 } 2681 } 2682 } 2683 2684 bool HadMultipleCandidates = (CandidateSet.size() > 1); 2685 2686 OverloadCandidateSet::iterator Best; 2687 switch (CandidateSet.BestViableFunction(S, From->getLocStart(), Best, true)) { 2688 case OR_Success: 2689 // Record the standard conversion we used and the conversion function. 2690 if (CXXConstructorDecl *Constructor 2691 = dyn_cast<CXXConstructorDecl>(Best->Function)) { 2692 S.MarkDeclarationReferenced(From->getLocStart(), Constructor); 2693 2694 // C++ [over.ics.user]p1: 2695 // If the user-defined conversion is specified by a 2696 // constructor (12.3.1), the initial standard conversion 2697 // sequence converts the source type to the type required by 2698 // the argument of the constructor. 2699 // 2700 QualType ThisType = Constructor->getThisType(S.Context); 2701 if (Best->Conversions[0].isEllipsis()) 2702 User.EllipsisConversion = true; 2703 else { 2704 User.Before = Best->Conversions[0].Standard; 2705 User.EllipsisConversion = false; 2706 } 2707 User.HadMultipleCandidates = HadMultipleCandidates; 2708 User.ConversionFunction = Constructor; 2709 User.FoundConversionFunction = Best->FoundDecl; 2710 User.After.setAsIdentityConversion(); 2711 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType()); 2712 User.After.setAllToTypes(ToType); 2713 return OR_Success; 2714 } else if (CXXConversionDecl *Conversion 2715 = dyn_cast<CXXConversionDecl>(Best->Function)) { 2716 S.MarkDeclarationReferenced(From->getLocStart(), Conversion); 2717 2718 // C++ [over.ics.user]p1: 2719 // 2720 // [...] If the user-defined conversion is specified by a 2721 // conversion function (12.3.2), the initial standard 2722 // conversion sequence converts the source type to the 2723 // implicit object parameter of the conversion function. 2724 User.Before = Best->Conversions[0].Standard; 2725 User.HadMultipleCandidates = HadMultipleCandidates; 2726 User.ConversionFunction = Conversion; 2727 User.FoundConversionFunction = Best->FoundDecl; 2728 User.EllipsisConversion = false; 2729 2730 // C++ [over.ics.user]p2: 2731 // The second standard conversion sequence converts the 2732 // result of the user-defined conversion to the target type 2733 // for the sequence. Since an implicit conversion sequence 2734 // is an initialization, the special rules for 2735 // initialization by user-defined conversion apply when 2736 // selecting the best user-defined conversion for a 2737 // user-defined conversion sequence (see 13.3.3 and 2738 // 13.3.3.1). 2739 User.After = Best->FinalConversion; 2740 return OR_Success; 2741 } else { 2742 llvm_unreachable("Not a constructor or conversion function?"); 2743 return OR_No_Viable_Function; 2744 } 2745 2746 case OR_No_Viable_Function: 2747 return OR_No_Viable_Function; 2748 case OR_Deleted: 2749 // No conversion here! We're done. 2750 return OR_Deleted; 2751 2752 case OR_Ambiguous: 2753 return OR_Ambiguous; 2754 } 2755 2756 return OR_No_Viable_Function; 2757} 2758 2759bool 2760Sema::DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType) { 2761 ImplicitConversionSequence ICS; 2762 OverloadCandidateSet CandidateSet(From->getExprLoc()); 2763 OverloadingResult OvResult = 2764 IsUserDefinedConversion(*this, From, ToType, ICS.UserDefined, 2765 CandidateSet, false); 2766 if (OvResult == OR_Ambiguous) 2767 Diag(From->getSourceRange().getBegin(), 2768 diag::err_typecheck_ambiguous_condition) 2769 << From->getType() << ToType << From->getSourceRange(); 2770 else if (OvResult == OR_No_Viable_Function && !CandidateSet.empty()) 2771 Diag(From->getSourceRange().getBegin(), 2772 diag::err_typecheck_nonviable_condition) 2773 << From->getType() << ToType << From->getSourceRange(); 2774 else 2775 return false; 2776 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &From, 1); 2777 return true; 2778} 2779 2780/// CompareImplicitConversionSequences - Compare two implicit 2781/// conversion sequences to determine whether one is better than the 2782/// other or if they are indistinguishable (C++ 13.3.3.2). 2783static ImplicitConversionSequence::CompareKind 2784CompareImplicitConversionSequences(Sema &S, 2785 const ImplicitConversionSequence& ICS1, 2786 const ImplicitConversionSequence& ICS2) 2787{ 2788 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit 2789 // conversion sequences (as defined in 13.3.3.1) 2790 // -- a standard conversion sequence (13.3.3.1.1) is a better 2791 // conversion sequence than a user-defined conversion sequence or 2792 // an ellipsis conversion sequence, and 2793 // -- a user-defined conversion sequence (13.3.3.1.2) is a better 2794 // conversion sequence than an ellipsis conversion sequence 2795 // (13.3.3.1.3). 2796 // 2797 // C++0x [over.best.ics]p10: 2798 // For the purpose of ranking implicit conversion sequences as 2799 // described in 13.3.3.2, the ambiguous conversion sequence is 2800 // treated as a user-defined sequence that is indistinguishable 2801 // from any other user-defined conversion sequence. 2802 if (ICS1.getKindRank() < ICS2.getKindRank()) 2803 return ImplicitConversionSequence::Better; 2804 else if (ICS2.getKindRank() < ICS1.getKindRank()) 2805 return ImplicitConversionSequence::Worse; 2806 2807 // The following checks require both conversion sequences to be of 2808 // the same kind. 2809 if (ICS1.getKind() != ICS2.getKind()) 2810 return ImplicitConversionSequence::Indistinguishable; 2811 2812 ImplicitConversionSequence::CompareKind Result = 2813 ImplicitConversionSequence::Indistinguishable; 2814 2815 // Two implicit conversion sequences of the same form are 2816 // indistinguishable conversion sequences unless one of the 2817 // following rules apply: (C++ 13.3.3.2p3): 2818 if (ICS1.isStandard()) 2819 Result = CompareStandardConversionSequences(S, 2820 ICS1.Standard, ICS2.Standard); 2821 else if (ICS1.isUserDefined()) { 2822 // User-defined conversion sequence U1 is a better conversion 2823 // sequence than another user-defined conversion sequence U2 if 2824 // they contain the same user-defined conversion function or 2825 // constructor and if the second standard conversion sequence of 2826 // U1 is better than the second standard conversion sequence of 2827 // U2 (C++ 13.3.3.2p3). 2828 if (ICS1.UserDefined.ConversionFunction == 2829 ICS2.UserDefined.ConversionFunction) 2830 Result = CompareStandardConversionSequences(S, 2831 ICS1.UserDefined.After, 2832 ICS2.UserDefined.After); 2833 } 2834 2835 // List-initialization sequence L1 is a better conversion sequence than 2836 // list-initialization sequence L2 if L1 converts to std::initializer_list<X> 2837 // for some X and L2 does not. 2838 if (Result == ImplicitConversionSequence::Indistinguishable && 2839 ICS1.isListInitializationSequence() && 2840 ICS2.isListInitializationSequence()) { 2841 // FIXME: Find out if ICS1 converts to initializer_list and ICS2 doesn't. 2842 } 2843 2844 return Result; 2845} 2846 2847static bool hasSimilarType(ASTContext &Context, QualType T1, QualType T2) { 2848 while (Context.UnwrapSimilarPointerTypes(T1, T2)) { 2849 Qualifiers Quals; 2850 T1 = Context.getUnqualifiedArrayType(T1, Quals); 2851 T2 = Context.getUnqualifiedArrayType(T2, Quals); 2852 } 2853 2854 return Context.hasSameUnqualifiedType(T1, T2); 2855} 2856 2857// Per 13.3.3.2p3, compare the given standard conversion sequences to 2858// determine if one is a proper subset of the other. 2859static ImplicitConversionSequence::CompareKind 2860compareStandardConversionSubsets(ASTContext &Context, 2861 const StandardConversionSequence& SCS1, 2862 const StandardConversionSequence& SCS2) { 2863 ImplicitConversionSequence::CompareKind Result 2864 = ImplicitConversionSequence::Indistinguishable; 2865 2866 // the identity conversion sequence is considered to be a subsequence of 2867 // any non-identity conversion sequence 2868 if (SCS1.isIdentityConversion() && !SCS2.isIdentityConversion()) 2869 return ImplicitConversionSequence::Better; 2870 else if (!SCS1.isIdentityConversion() && SCS2.isIdentityConversion()) 2871 return ImplicitConversionSequence::Worse; 2872 2873 if (SCS1.Second != SCS2.Second) { 2874 if (SCS1.Second == ICK_Identity) 2875 Result = ImplicitConversionSequence::Better; 2876 else if (SCS2.Second == ICK_Identity) 2877 Result = ImplicitConversionSequence::Worse; 2878 else 2879 return ImplicitConversionSequence::Indistinguishable; 2880 } else if (!hasSimilarType(Context, SCS1.getToType(1), SCS2.getToType(1))) 2881 return ImplicitConversionSequence::Indistinguishable; 2882 2883 if (SCS1.Third == SCS2.Third) { 2884 return Context.hasSameType(SCS1.getToType(2), SCS2.getToType(2))? Result 2885 : ImplicitConversionSequence::Indistinguishable; 2886 } 2887 2888 if (SCS1.Third == ICK_Identity) 2889 return Result == ImplicitConversionSequence::Worse 2890 ? ImplicitConversionSequence::Indistinguishable 2891 : ImplicitConversionSequence::Better; 2892 2893 if (SCS2.Third == ICK_Identity) 2894 return Result == ImplicitConversionSequence::Better 2895 ? ImplicitConversionSequence::Indistinguishable 2896 : ImplicitConversionSequence::Worse; 2897 2898 return ImplicitConversionSequence::Indistinguishable; 2899} 2900 2901/// \brief Determine whether one of the given reference bindings is better 2902/// than the other based on what kind of bindings they are. 2903static bool isBetterReferenceBindingKind(const StandardConversionSequence &SCS1, 2904 const StandardConversionSequence &SCS2) { 2905 // C++0x [over.ics.rank]p3b4: 2906 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an 2907 // implicit object parameter of a non-static member function declared 2908 // without a ref-qualifier, and *either* S1 binds an rvalue reference 2909 // to an rvalue and S2 binds an lvalue reference *or S1 binds an 2910 // lvalue reference to a function lvalue and S2 binds an rvalue 2911 // reference*. 2912 // 2913 // FIXME: Rvalue references. We're going rogue with the above edits, 2914 // because the semantics in the current C++0x working paper (N3225 at the 2915 // time of this writing) break the standard definition of std::forward 2916 // and std::reference_wrapper when dealing with references to functions. 2917 // Proposed wording changes submitted to CWG for consideration. 2918 if (SCS1.BindsImplicitObjectArgumentWithoutRefQualifier || 2919 SCS2.BindsImplicitObjectArgumentWithoutRefQualifier) 2920 return false; 2921 2922 return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue && 2923 SCS2.IsLvalueReference) || 2924 (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue && 2925 !SCS2.IsLvalueReference); 2926} 2927 2928/// CompareStandardConversionSequences - Compare two standard 2929/// conversion sequences to determine whether one is better than the 2930/// other or if they are indistinguishable (C++ 13.3.3.2p3). 2931static ImplicitConversionSequence::CompareKind 2932CompareStandardConversionSequences(Sema &S, 2933 const StandardConversionSequence& SCS1, 2934 const StandardConversionSequence& SCS2) 2935{ 2936 // Standard conversion sequence S1 is a better conversion sequence 2937 // than standard conversion sequence S2 if (C++ 13.3.3.2p3): 2938 2939 // -- S1 is a proper subsequence of S2 (comparing the conversion 2940 // sequences in the canonical form defined by 13.3.3.1.1, 2941 // excluding any Lvalue Transformation; the identity conversion 2942 // sequence is considered to be a subsequence of any 2943 // non-identity conversion sequence) or, if not that, 2944 if (ImplicitConversionSequence::CompareKind CK 2945 = compareStandardConversionSubsets(S.Context, SCS1, SCS2)) 2946 return CK; 2947 2948 // -- the rank of S1 is better than the rank of S2 (by the rules 2949 // defined below), or, if not that, 2950 ImplicitConversionRank Rank1 = SCS1.getRank(); 2951 ImplicitConversionRank Rank2 = SCS2.getRank(); 2952 if (Rank1 < Rank2) 2953 return ImplicitConversionSequence::Better; 2954 else if (Rank2 < Rank1) 2955 return ImplicitConversionSequence::Worse; 2956 2957 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank 2958 // are indistinguishable unless one of the following rules 2959 // applies: 2960 2961 // A conversion that is not a conversion of a pointer, or 2962 // pointer to member, to bool is better than another conversion 2963 // that is such a conversion. 2964 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool()) 2965 return SCS2.isPointerConversionToBool() 2966 ? ImplicitConversionSequence::Better 2967 : ImplicitConversionSequence::Worse; 2968 2969 // C++ [over.ics.rank]p4b2: 2970 // 2971 // If class B is derived directly or indirectly from class A, 2972 // conversion of B* to A* is better than conversion of B* to 2973 // void*, and conversion of A* to void* is better than conversion 2974 // of B* to void*. 2975 bool SCS1ConvertsToVoid 2976 = SCS1.isPointerConversionToVoidPointer(S.Context); 2977 bool SCS2ConvertsToVoid 2978 = SCS2.isPointerConversionToVoidPointer(S.Context); 2979 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) { 2980 // Exactly one of the conversion sequences is a conversion to 2981 // a void pointer; it's the worse conversion. 2982 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better 2983 : ImplicitConversionSequence::Worse; 2984 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) { 2985 // Neither conversion sequence converts to a void pointer; compare 2986 // their derived-to-base conversions. 2987 if (ImplicitConversionSequence::CompareKind DerivedCK 2988 = CompareDerivedToBaseConversions(S, SCS1, SCS2)) 2989 return DerivedCK; 2990 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid && 2991 !S.Context.hasSameType(SCS1.getFromType(), SCS2.getFromType())) { 2992 // Both conversion sequences are conversions to void 2993 // pointers. Compare the source types to determine if there's an 2994 // inheritance relationship in their sources. 2995 QualType FromType1 = SCS1.getFromType(); 2996 QualType FromType2 = SCS2.getFromType(); 2997 2998 // Adjust the types we're converting from via the array-to-pointer 2999 // conversion, if we need to. 3000 if (SCS1.First == ICK_Array_To_Pointer) 3001 FromType1 = S.Context.getArrayDecayedType(FromType1); 3002 if (SCS2.First == ICK_Array_To_Pointer) 3003 FromType2 = S.Context.getArrayDecayedType(FromType2); 3004 3005 QualType FromPointee1 = FromType1->getPointeeType().getUnqualifiedType(); 3006 QualType FromPointee2 = FromType2->getPointeeType().getUnqualifiedType(); 3007 3008 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3009 return ImplicitConversionSequence::Better; 3010 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3011 return ImplicitConversionSequence::Worse; 3012 3013 // Objective-C++: If one interface is more specific than the 3014 // other, it is the better one. 3015 const ObjCObjectPointerType* FromObjCPtr1 3016 = FromType1->getAs<ObjCObjectPointerType>(); 3017 const ObjCObjectPointerType* FromObjCPtr2 3018 = FromType2->getAs<ObjCObjectPointerType>(); 3019 if (FromObjCPtr1 && FromObjCPtr2) { 3020 bool AssignLeft = S.Context.canAssignObjCInterfaces(FromObjCPtr1, 3021 FromObjCPtr2); 3022 bool AssignRight = S.Context.canAssignObjCInterfaces(FromObjCPtr2, 3023 FromObjCPtr1); 3024 if (AssignLeft != AssignRight) { 3025 return AssignLeft? ImplicitConversionSequence::Better 3026 : ImplicitConversionSequence::Worse; 3027 } 3028 } 3029 } 3030 3031 // Compare based on qualification conversions (C++ 13.3.3.2p3, 3032 // bullet 3). 3033 if (ImplicitConversionSequence::CompareKind QualCK 3034 = CompareQualificationConversions(S, SCS1, SCS2)) 3035 return QualCK; 3036 3037 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) { 3038 // Check for a better reference binding based on the kind of bindings. 3039 if (isBetterReferenceBindingKind(SCS1, SCS2)) 3040 return ImplicitConversionSequence::Better; 3041 else if (isBetterReferenceBindingKind(SCS2, SCS1)) 3042 return ImplicitConversionSequence::Worse; 3043 3044 // C++ [over.ics.rank]p3b4: 3045 // -- S1 and S2 are reference bindings (8.5.3), and the types to 3046 // which the references refer are the same type except for 3047 // top-level cv-qualifiers, and the type to which the reference 3048 // initialized by S2 refers is more cv-qualified than the type 3049 // to which the reference initialized by S1 refers. 3050 QualType T1 = SCS1.getToType(2); 3051 QualType T2 = SCS2.getToType(2); 3052 T1 = S.Context.getCanonicalType(T1); 3053 T2 = S.Context.getCanonicalType(T2); 3054 Qualifiers T1Quals, T2Quals; 3055 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 3056 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 3057 if (UnqualT1 == UnqualT2) { 3058 // Objective-C++ ARC: If the references refer to objects with different 3059 // lifetimes, prefer bindings that don't change lifetime. 3060 if (SCS1.ObjCLifetimeConversionBinding != 3061 SCS2.ObjCLifetimeConversionBinding) { 3062 return SCS1.ObjCLifetimeConversionBinding 3063 ? ImplicitConversionSequence::Worse 3064 : ImplicitConversionSequence::Better; 3065 } 3066 3067 // If the type is an array type, promote the element qualifiers to the 3068 // type for comparison. 3069 if (isa<ArrayType>(T1) && T1Quals) 3070 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 3071 if (isa<ArrayType>(T2) && T2Quals) 3072 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 3073 if (T2.isMoreQualifiedThan(T1)) 3074 return ImplicitConversionSequence::Better; 3075 else if (T1.isMoreQualifiedThan(T2)) 3076 return ImplicitConversionSequence::Worse; 3077 } 3078 } 3079 3080 // In Microsoft mode, prefer an integral conversion to a 3081 // floating-to-integral conversion if the integral conversion 3082 // is between types of the same size. 3083 // For example: 3084 // void f(float); 3085 // void f(int); 3086 // int main { 3087 // long a; 3088 // f(a); 3089 // } 3090 // Here, MSVC will call f(int) instead of generating a compile error 3091 // as clang will do in standard mode. 3092 if (S.getLangOptions().MicrosoftMode && 3093 SCS1.Second == ICK_Integral_Conversion && 3094 SCS2.Second == ICK_Floating_Integral && 3095 S.Context.getTypeSize(SCS1.getFromType()) == 3096 S.Context.getTypeSize(SCS1.getToType(2))) 3097 return ImplicitConversionSequence::Better; 3098 3099 return ImplicitConversionSequence::Indistinguishable; 3100} 3101 3102/// CompareQualificationConversions - Compares two standard conversion 3103/// sequences to determine whether they can be ranked based on their 3104/// qualification conversions (C++ 13.3.3.2p3 bullet 3). 3105ImplicitConversionSequence::CompareKind 3106CompareQualificationConversions(Sema &S, 3107 const StandardConversionSequence& SCS1, 3108 const StandardConversionSequence& SCS2) { 3109 // C++ 13.3.3.2p3: 3110 // -- S1 and S2 differ only in their qualification conversion and 3111 // yield similar types T1 and T2 (C++ 4.4), respectively, and the 3112 // cv-qualification signature of type T1 is a proper subset of 3113 // the cv-qualification signature of type T2, and S1 is not the 3114 // deprecated string literal array-to-pointer conversion (4.2). 3115 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second || 3116 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification) 3117 return ImplicitConversionSequence::Indistinguishable; 3118 3119 // FIXME: the example in the standard doesn't use a qualification 3120 // conversion (!) 3121 QualType T1 = SCS1.getToType(2); 3122 QualType T2 = SCS2.getToType(2); 3123 T1 = S.Context.getCanonicalType(T1); 3124 T2 = S.Context.getCanonicalType(T2); 3125 Qualifiers T1Quals, T2Quals; 3126 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 3127 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 3128 3129 // If the types are the same, we won't learn anything by unwrapped 3130 // them. 3131 if (UnqualT1 == UnqualT2) 3132 return ImplicitConversionSequence::Indistinguishable; 3133 3134 // If the type is an array type, promote the element qualifiers to the type 3135 // for comparison. 3136 if (isa<ArrayType>(T1) && T1Quals) 3137 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 3138 if (isa<ArrayType>(T2) && T2Quals) 3139 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 3140 3141 ImplicitConversionSequence::CompareKind Result 3142 = ImplicitConversionSequence::Indistinguishable; 3143 3144 // Objective-C++ ARC: 3145 // Prefer qualification conversions not involving a change in lifetime 3146 // to qualification conversions that do not change lifetime. 3147 if (SCS1.QualificationIncludesObjCLifetime != 3148 SCS2.QualificationIncludesObjCLifetime) { 3149 Result = SCS1.QualificationIncludesObjCLifetime 3150 ? ImplicitConversionSequence::Worse 3151 : ImplicitConversionSequence::Better; 3152 } 3153 3154 while (S.Context.UnwrapSimilarPointerTypes(T1, T2)) { 3155 // Within each iteration of the loop, we check the qualifiers to 3156 // determine if this still looks like a qualification 3157 // conversion. Then, if all is well, we unwrap one more level of 3158 // pointers or pointers-to-members and do it all again 3159 // until there are no more pointers or pointers-to-members left 3160 // to unwrap. This essentially mimics what 3161 // IsQualificationConversion does, but here we're checking for a 3162 // strict subset of qualifiers. 3163 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 3164 // The qualifiers are the same, so this doesn't tell us anything 3165 // about how the sequences rank. 3166 ; 3167 else if (T2.isMoreQualifiedThan(T1)) { 3168 // T1 has fewer qualifiers, so it could be the better sequence. 3169 if (Result == ImplicitConversionSequence::Worse) 3170 // Neither has qualifiers that are a subset of the other's 3171 // qualifiers. 3172 return ImplicitConversionSequence::Indistinguishable; 3173 3174 Result = ImplicitConversionSequence::Better; 3175 } else if (T1.isMoreQualifiedThan(T2)) { 3176 // T2 has fewer qualifiers, so it could be the better sequence. 3177 if (Result == ImplicitConversionSequence::Better) 3178 // Neither has qualifiers that are a subset of the other's 3179 // qualifiers. 3180 return ImplicitConversionSequence::Indistinguishable; 3181 3182 Result = ImplicitConversionSequence::Worse; 3183 } else { 3184 // Qualifiers are disjoint. 3185 return ImplicitConversionSequence::Indistinguishable; 3186 } 3187 3188 // If the types after this point are equivalent, we're done. 3189 if (S.Context.hasSameUnqualifiedType(T1, T2)) 3190 break; 3191 } 3192 3193 // Check that the winning standard conversion sequence isn't using 3194 // the deprecated string literal array to pointer conversion. 3195 switch (Result) { 3196 case ImplicitConversionSequence::Better: 3197 if (SCS1.DeprecatedStringLiteralToCharPtr) 3198 Result = ImplicitConversionSequence::Indistinguishable; 3199 break; 3200 3201 case ImplicitConversionSequence::Indistinguishable: 3202 break; 3203 3204 case ImplicitConversionSequence::Worse: 3205 if (SCS2.DeprecatedStringLiteralToCharPtr) 3206 Result = ImplicitConversionSequence::Indistinguishable; 3207 break; 3208 } 3209 3210 return Result; 3211} 3212 3213/// CompareDerivedToBaseConversions - Compares two standard conversion 3214/// sequences to determine whether they can be ranked based on their 3215/// various kinds of derived-to-base conversions (C++ 3216/// [over.ics.rank]p4b3). As part of these checks, we also look at 3217/// conversions between Objective-C interface types. 3218ImplicitConversionSequence::CompareKind 3219CompareDerivedToBaseConversions(Sema &S, 3220 const StandardConversionSequence& SCS1, 3221 const StandardConversionSequence& SCS2) { 3222 QualType FromType1 = SCS1.getFromType(); 3223 QualType ToType1 = SCS1.getToType(1); 3224 QualType FromType2 = SCS2.getFromType(); 3225 QualType ToType2 = SCS2.getToType(1); 3226 3227 // Adjust the types we're converting from via the array-to-pointer 3228 // conversion, if we need to. 3229 if (SCS1.First == ICK_Array_To_Pointer) 3230 FromType1 = S.Context.getArrayDecayedType(FromType1); 3231 if (SCS2.First == ICK_Array_To_Pointer) 3232 FromType2 = S.Context.getArrayDecayedType(FromType2); 3233 3234 // Canonicalize all of the types. 3235 FromType1 = S.Context.getCanonicalType(FromType1); 3236 ToType1 = S.Context.getCanonicalType(ToType1); 3237 FromType2 = S.Context.getCanonicalType(FromType2); 3238 ToType2 = S.Context.getCanonicalType(ToType2); 3239 3240 // C++ [over.ics.rank]p4b3: 3241 // 3242 // If class B is derived directly or indirectly from class A and 3243 // class C is derived directly or indirectly from B, 3244 // 3245 // Compare based on pointer conversions. 3246 if (SCS1.Second == ICK_Pointer_Conversion && 3247 SCS2.Second == ICK_Pointer_Conversion && 3248 /*FIXME: Remove if Objective-C id conversions get their own rank*/ 3249 FromType1->isPointerType() && FromType2->isPointerType() && 3250 ToType1->isPointerType() && ToType2->isPointerType()) { 3251 QualType FromPointee1 3252 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3253 QualType ToPointee1 3254 = ToType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3255 QualType FromPointee2 3256 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3257 QualType ToPointee2 3258 = ToType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3259 3260 // -- conversion of C* to B* is better than conversion of C* to A*, 3261 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 3262 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 3263 return ImplicitConversionSequence::Better; 3264 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 3265 return ImplicitConversionSequence::Worse; 3266 } 3267 3268 // -- conversion of B* to A* is better than conversion of C* to A*, 3269 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) { 3270 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3271 return ImplicitConversionSequence::Better; 3272 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3273 return ImplicitConversionSequence::Worse; 3274 } 3275 } else if (SCS1.Second == ICK_Pointer_Conversion && 3276 SCS2.Second == ICK_Pointer_Conversion) { 3277 const ObjCObjectPointerType *FromPtr1 3278 = FromType1->getAs<ObjCObjectPointerType>(); 3279 const ObjCObjectPointerType *FromPtr2 3280 = FromType2->getAs<ObjCObjectPointerType>(); 3281 const ObjCObjectPointerType *ToPtr1 3282 = ToType1->getAs<ObjCObjectPointerType>(); 3283 const ObjCObjectPointerType *ToPtr2 3284 = ToType2->getAs<ObjCObjectPointerType>(); 3285 3286 if (FromPtr1 && FromPtr2 && ToPtr1 && ToPtr2) { 3287 // Apply the same conversion ranking rules for Objective-C pointer types 3288 // that we do for C++ pointers to class types. However, we employ the 3289 // Objective-C pseudo-subtyping relationship used for assignment of 3290 // Objective-C pointer types. 3291 bool FromAssignLeft 3292 = S.Context.canAssignObjCInterfaces(FromPtr1, FromPtr2); 3293 bool FromAssignRight 3294 = S.Context.canAssignObjCInterfaces(FromPtr2, FromPtr1); 3295 bool ToAssignLeft 3296 = S.Context.canAssignObjCInterfaces(ToPtr1, ToPtr2); 3297 bool ToAssignRight 3298 = S.Context.canAssignObjCInterfaces(ToPtr2, ToPtr1); 3299 3300 // A conversion to an a non-id object pointer type or qualified 'id' 3301 // type is better than a conversion to 'id'. 3302 if (ToPtr1->isObjCIdType() && 3303 (ToPtr2->isObjCQualifiedIdType() || ToPtr2->getInterfaceDecl())) 3304 return ImplicitConversionSequence::Worse; 3305 if (ToPtr2->isObjCIdType() && 3306 (ToPtr1->isObjCQualifiedIdType() || ToPtr1->getInterfaceDecl())) 3307 return ImplicitConversionSequence::Better; 3308 3309 // A conversion to a non-id object pointer type is better than a 3310 // conversion to a qualified 'id' type 3311 if (ToPtr1->isObjCQualifiedIdType() && ToPtr2->getInterfaceDecl()) 3312 return ImplicitConversionSequence::Worse; 3313 if (ToPtr2->isObjCQualifiedIdType() && ToPtr1->getInterfaceDecl()) 3314 return ImplicitConversionSequence::Better; 3315 3316 // A conversion to an a non-Class object pointer type or qualified 'Class' 3317 // type is better than a conversion to 'Class'. 3318 if (ToPtr1->isObjCClassType() && 3319 (ToPtr2->isObjCQualifiedClassType() || ToPtr2->getInterfaceDecl())) 3320 return ImplicitConversionSequence::Worse; 3321 if (ToPtr2->isObjCClassType() && 3322 (ToPtr1->isObjCQualifiedClassType() || ToPtr1->getInterfaceDecl())) 3323 return ImplicitConversionSequence::Better; 3324 3325 // A conversion to a non-Class object pointer type is better than a 3326 // conversion to a qualified 'Class' type. 3327 if (ToPtr1->isObjCQualifiedClassType() && ToPtr2->getInterfaceDecl()) 3328 return ImplicitConversionSequence::Worse; 3329 if (ToPtr2->isObjCQualifiedClassType() && ToPtr1->getInterfaceDecl()) 3330 return ImplicitConversionSequence::Better; 3331 3332 // -- "conversion of C* to B* is better than conversion of C* to A*," 3333 if (S.Context.hasSameType(FromType1, FromType2) && 3334 !FromPtr1->isObjCIdType() && !FromPtr1->isObjCClassType() && 3335 (ToAssignLeft != ToAssignRight)) 3336 return ToAssignLeft? ImplicitConversionSequence::Worse 3337 : ImplicitConversionSequence::Better; 3338 3339 // -- "conversion of B* to A* is better than conversion of C* to A*," 3340 if (S.Context.hasSameUnqualifiedType(ToType1, ToType2) && 3341 (FromAssignLeft != FromAssignRight)) 3342 return FromAssignLeft? ImplicitConversionSequence::Better 3343 : ImplicitConversionSequence::Worse; 3344 } 3345 } 3346 3347 // Ranking of member-pointer types. 3348 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member && 3349 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() && 3350 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) { 3351 const MemberPointerType * FromMemPointer1 = 3352 FromType1->getAs<MemberPointerType>(); 3353 const MemberPointerType * ToMemPointer1 = 3354 ToType1->getAs<MemberPointerType>(); 3355 const MemberPointerType * FromMemPointer2 = 3356 FromType2->getAs<MemberPointerType>(); 3357 const MemberPointerType * ToMemPointer2 = 3358 ToType2->getAs<MemberPointerType>(); 3359 const Type *FromPointeeType1 = FromMemPointer1->getClass(); 3360 const Type *ToPointeeType1 = ToMemPointer1->getClass(); 3361 const Type *FromPointeeType2 = FromMemPointer2->getClass(); 3362 const Type *ToPointeeType2 = ToMemPointer2->getClass(); 3363 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType(); 3364 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType(); 3365 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType(); 3366 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType(); 3367 // conversion of A::* to B::* is better than conversion of A::* to C::*, 3368 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 3369 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 3370 return ImplicitConversionSequence::Worse; 3371 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 3372 return ImplicitConversionSequence::Better; 3373 } 3374 // conversion of B::* to C::* is better than conversion of A::* to C::* 3375 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) { 3376 if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3377 return ImplicitConversionSequence::Better; 3378 else if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3379 return ImplicitConversionSequence::Worse; 3380 } 3381 } 3382 3383 if (SCS1.Second == ICK_Derived_To_Base) { 3384 // -- conversion of C to B is better than conversion of C to A, 3385 // -- binding of an expression of type C to a reference of type 3386 // B& is better than binding an expression of type C to a 3387 // reference of type A&, 3388 if (S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3389 !S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3390 if (S.IsDerivedFrom(ToType1, ToType2)) 3391 return ImplicitConversionSequence::Better; 3392 else if (S.IsDerivedFrom(ToType2, ToType1)) 3393 return ImplicitConversionSequence::Worse; 3394 } 3395 3396 // -- conversion of B to A is better than conversion of C to A. 3397 // -- binding of an expression of type B to a reference of type 3398 // A& is better than binding an expression of type C to a 3399 // reference of type A&, 3400 if (!S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3401 S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3402 if (S.IsDerivedFrom(FromType2, FromType1)) 3403 return ImplicitConversionSequence::Better; 3404 else if (S.IsDerivedFrom(FromType1, FromType2)) 3405 return ImplicitConversionSequence::Worse; 3406 } 3407 } 3408 3409 return ImplicitConversionSequence::Indistinguishable; 3410} 3411 3412/// CompareReferenceRelationship - Compare the two types T1 and T2 to 3413/// determine whether they are reference-related, 3414/// reference-compatible, reference-compatible with added 3415/// qualification, or incompatible, for use in C++ initialization by 3416/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 3417/// type, and the first type (T1) is the pointee type of the reference 3418/// type being initialized. 3419Sema::ReferenceCompareResult 3420Sema::CompareReferenceRelationship(SourceLocation Loc, 3421 QualType OrigT1, QualType OrigT2, 3422 bool &DerivedToBase, 3423 bool &ObjCConversion, 3424 bool &ObjCLifetimeConversion) { 3425 assert(!OrigT1->isReferenceType() && 3426 "T1 must be the pointee type of the reference type"); 3427 assert(!OrigT2->isReferenceType() && "T2 cannot be a reference type"); 3428 3429 QualType T1 = Context.getCanonicalType(OrigT1); 3430 QualType T2 = Context.getCanonicalType(OrigT2); 3431 Qualifiers T1Quals, T2Quals; 3432 QualType UnqualT1 = Context.getUnqualifiedArrayType(T1, T1Quals); 3433 QualType UnqualT2 = Context.getUnqualifiedArrayType(T2, T2Quals); 3434 3435 // C++ [dcl.init.ref]p4: 3436 // Given types "cv1 T1" and "cv2 T2," "cv1 T1" is 3437 // reference-related to "cv2 T2" if T1 is the same type as T2, or 3438 // T1 is a base class of T2. 3439 DerivedToBase = false; 3440 ObjCConversion = false; 3441 ObjCLifetimeConversion = false; 3442 if (UnqualT1 == UnqualT2) { 3443 // Nothing to do. 3444 } else if (!RequireCompleteType(Loc, OrigT2, PDiag()) && 3445 IsDerivedFrom(UnqualT2, UnqualT1)) 3446 DerivedToBase = true; 3447 else if (UnqualT1->isObjCObjectOrInterfaceType() && 3448 UnqualT2->isObjCObjectOrInterfaceType() && 3449 Context.canBindObjCObjectType(UnqualT1, UnqualT2)) 3450 ObjCConversion = true; 3451 else 3452 return Ref_Incompatible; 3453 3454 // At this point, we know that T1 and T2 are reference-related (at 3455 // least). 3456 3457 // If the type is an array type, promote the element qualifiers to the type 3458 // for comparison. 3459 if (isa<ArrayType>(T1) && T1Quals) 3460 T1 = Context.getQualifiedType(UnqualT1, T1Quals); 3461 if (isa<ArrayType>(T2) && T2Quals) 3462 T2 = Context.getQualifiedType(UnqualT2, T2Quals); 3463 3464 // C++ [dcl.init.ref]p4: 3465 // "cv1 T1" is reference-compatible with "cv2 T2" if T1 is 3466 // reference-related to T2 and cv1 is the same cv-qualification 3467 // as, or greater cv-qualification than, cv2. For purposes of 3468 // overload resolution, cases for which cv1 is greater 3469 // cv-qualification than cv2 are identified as 3470 // reference-compatible with added qualification (see 13.3.3.2). 3471 // 3472 // Note that we also require equivalence of Objective-C GC and address-space 3473 // qualifiers when performing these computations, so that e.g., an int in 3474 // address space 1 is not reference-compatible with an int in address 3475 // space 2. 3476 if (T1Quals.getObjCLifetime() != T2Quals.getObjCLifetime() && 3477 T1Quals.compatiblyIncludesObjCLifetime(T2Quals)) { 3478 T1Quals.removeObjCLifetime(); 3479 T2Quals.removeObjCLifetime(); 3480 ObjCLifetimeConversion = true; 3481 } 3482 3483 if (T1Quals == T2Quals) 3484 return Ref_Compatible; 3485 else if (T1Quals.compatiblyIncludes(T2Quals)) 3486 return Ref_Compatible_With_Added_Qualification; 3487 else 3488 return Ref_Related; 3489} 3490 3491/// \brief Look for a user-defined conversion to an value reference-compatible 3492/// with DeclType. Return true if something definite is found. 3493static bool 3494FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS, 3495 QualType DeclType, SourceLocation DeclLoc, 3496 Expr *Init, QualType T2, bool AllowRvalues, 3497 bool AllowExplicit) { 3498 assert(T2->isRecordType() && "Can only find conversions of record types."); 3499 CXXRecordDecl *T2RecordDecl 3500 = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl()); 3501 3502 OverloadCandidateSet CandidateSet(DeclLoc); 3503 const UnresolvedSetImpl *Conversions 3504 = T2RecordDecl->getVisibleConversionFunctions(); 3505 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3506 E = Conversions->end(); I != E; ++I) { 3507 NamedDecl *D = *I; 3508 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3509 if (isa<UsingShadowDecl>(D)) 3510 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3511 3512 FunctionTemplateDecl *ConvTemplate 3513 = dyn_cast<FunctionTemplateDecl>(D); 3514 CXXConversionDecl *Conv; 3515 if (ConvTemplate) 3516 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3517 else 3518 Conv = cast<CXXConversionDecl>(D); 3519 3520 // If this is an explicit conversion, and we're not allowed to consider 3521 // explicit conversions, skip it. 3522 if (!AllowExplicit && Conv->isExplicit()) 3523 continue; 3524 3525 if (AllowRvalues) { 3526 bool DerivedToBase = false; 3527 bool ObjCConversion = false; 3528 bool ObjCLifetimeConversion = false; 3529 3530 // If we are initializing an rvalue reference, don't permit conversion 3531 // functions that return lvalues. 3532 if (!ConvTemplate && DeclType->isRValueReferenceType()) { 3533 const ReferenceType *RefType 3534 = Conv->getConversionType()->getAs<LValueReferenceType>(); 3535 if (RefType && !RefType->getPointeeType()->isFunctionType()) 3536 continue; 3537 } 3538 3539 if (!ConvTemplate && 3540 S.CompareReferenceRelationship( 3541 DeclLoc, 3542 Conv->getConversionType().getNonReferenceType() 3543 .getUnqualifiedType(), 3544 DeclType.getNonReferenceType().getUnqualifiedType(), 3545 DerivedToBase, ObjCConversion, ObjCLifetimeConversion) == 3546 Sema::Ref_Incompatible) 3547 continue; 3548 } else { 3549 // If the conversion function doesn't return a reference type, 3550 // it can't be considered for this conversion. An rvalue reference 3551 // is only acceptable if its referencee is a function type. 3552 3553 const ReferenceType *RefType = 3554 Conv->getConversionType()->getAs<ReferenceType>(); 3555 if (!RefType || 3556 (!RefType->isLValueReferenceType() && 3557 !RefType->getPointeeType()->isFunctionType())) 3558 continue; 3559 } 3560 3561 if (ConvTemplate) 3562 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), ActingDC, 3563 Init, DeclType, CandidateSet); 3564 else 3565 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Init, 3566 DeclType, CandidateSet); 3567 } 3568 3569 bool HadMultipleCandidates = (CandidateSet.size() > 1); 3570 3571 OverloadCandidateSet::iterator Best; 3572 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 3573 case OR_Success: 3574 // C++ [over.ics.ref]p1: 3575 // 3576 // [...] If the parameter binds directly to the result of 3577 // applying a conversion function to the argument 3578 // expression, the implicit conversion sequence is a 3579 // user-defined conversion sequence (13.3.3.1.2), with the 3580 // second standard conversion sequence either an identity 3581 // conversion or, if the conversion function returns an 3582 // entity of a type that is a derived class of the parameter 3583 // type, a derived-to-base Conversion. 3584 if (!Best->FinalConversion.DirectBinding) 3585 return false; 3586 3587 if (Best->Function) 3588 S.MarkDeclarationReferenced(DeclLoc, Best->Function); 3589 ICS.setUserDefined(); 3590 ICS.UserDefined.Before = Best->Conversions[0].Standard; 3591 ICS.UserDefined.After = Best->FinalConversion; 3592 ICS.UserDefined.HadMultipleCandidates = HadMultipleCandidates; 3593 ICS.UserDefined.ConversionFunction = Best->Function; 3594 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl; 3595 ICS.UserDefined.EllipsisConversion = false; 3596 assert(ICS.UserDefined.After.ReferenceBinding && 3597 ICS.UserDefined.After.DirectBinding && 3598 "Expected a direct reference binding!"); 3599 return true; 3600 3601 case OR_Ambiguous: 3602 ICS.setAmbiguous(); 3603 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 3604 Cand != CandidateSet.end(); ++Cand) 3605 if (Cand->Viable) 3606 ICS.Ambiguous.addConversion(Cand->Function); 3607 return true; 3608 3609 case OR_No_Viable_Function: 3610 case OR_Deleted: 3611 // There was no suitable conversion, or we found a deleted 3612 // conversion; continue with other checks. 3613 return false; 3614 } 3615 3616 return false; 3617} 3618 3619/// \brief Compute an implicit conversion sequence for reference 3620/// initialization. 3621static ImplicitConversionSequence 3622TryReferenceInit(Sema &S, Expr *&Init, QualType DeclType, 3623 SourceLocation DeclLoc, 3624 bool SuppressUserConversions, 3625 bool AllowExplicit) { 3626 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 3627 3628 // Most paths end in a failed conversion. 3629 ImplicitConversionSequence ICS; 3630 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3631 3632 QualType T1 = DeclType->getAs<ReferenceType>()->getPointeeType(); 3633 QualType T2 = Init->getType(); 3634 3635 // If the initializer is the address of an overloaded function, try 3636 // to resolve the overloaded function. If all goes well, T2 is the 3637 // type of the resulting function. 3638 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 3639 DeclAccessPair Found; 3640 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType, 3641 false, Found)) 3642 T2 = Fn->getType(); 3643 } 3644 3645 // Compute some basic properties of the types and the initializer. 3646 bool isRValRef = DeclType->isRValueReferenceType(); 3647 bool DerivedToBase = false; 3648 bool ObjCConversion = false; 3649 bool ObjCLifetimeConversion = false; 3650 Expr::Classification InitCategory = Init->Classify(S.Context); 3651 Sema::ReferenceCompareResult RefRelationship 3652 = S.CompareReferenceRelationship(DeclLoc, T1, T2, DerivedToBase, 3653 ObjCConversion, ObjCLifetimeConversion); 3654 3655 3656 // C++0x [dcl.init.ref]p5: 3657 // A reference to type "cv1 T1" is initialized by an expression 3658 // of type "cv2 T2" as follows: 3659 3660 // -- If reference is an lvalue reference and the initializer expression 3661 if (!isRValRef) { 3662 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is 3663 // reference-compatible with "cv2 T2," or 3664 // 3665 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here. 3666 if (InitCategory.isLValue() && 3667 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 3668 // C++ [over.ics.ref]p1: 3669 // When a parameter of reference type binds directly (8.5.3) 3670 // to an argument expression, the implicit conversion sequence 3671 // is the identity conversion, unless the argument expression 3672 // has a type that is a derived class of the parameter type, 3673 // in which case the implicit conversion sequence is a 3674 // derived-to-base Conversion (13.3.3.1). 3675 ICS.setStandard(); 3676 ICS.Standard.First = ICK_Identity; 3677 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3678 : ObjCConversion? ICK_Compatible_Conversion 3679 : ICK_Identity; 3680 ICS.Standard.Third = ICK_Identity; 3681 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3682 ICS.Standard.setToType(0, T2); 3683 ICS.Standard.setToType(1, T1); 3684 ICS.Standard.setToType(2, T1); 3685 ICS.Standard.ReferenceBinding = true; 3686 ICS.Standard.DirectBinding = true; 3687 ICS.Standard.IsLvalueReference = !isRValRef; 3688 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3689 ICS.Standard.BindsToRvalue = false; 3690 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3691 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion; 3692 ICS.Standard.CopyConstructor = 0; 3693 3694 // Nothing more to do: the inaccessibility/ambiguity check for 3695 // derived-to-base conversions is suppressed when we're 3696 // computing the implicit conversion sequence (C++ 3697 // [over.best.ics]p2). 3698 return ICS; 3699 } 3700 3701 // -- has a class type (i.e., T2 is a class type), where T1 is 3702 // not reference-related to T2, and can be implicitly 3703 // converted to an lvalue of type "cv3 T3," where "cv1 T1" 3704 // is reference-compatible with "cv3 T3" 92) (this 3705 // conversion is selected by enumerating the applicable 3706 // conversion functions (13.3.1.6) and choosing the best 3707 // one through overload resolution (13.3)), 3708 if (!SuppressUserConversions && T2->isRecordType() && 3709 !S.RequireCompleteType(DeclLoc, T2, 0) && 3710 RefRelationship == Sema::Ref_Incompatible) { 3711 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3712 Init, T2, /*AllowRvalues=*/false, 3713 AllowExplicit)) 3714 return ICS; 3715 } 3716 } 3717 3718 // -- Otherwise, the reference shall be an lvalue reference to a 3719 // non-volatile const type (i.e., cv1 shall be const), or the reference 3720 // shall be an rvalue reference. 3721 // 3722 // We actually handle one oddity of C++ [over.ics.ref] at this 3723 // point, which is that, due to p2 (which short-circuits reference 3724 // binding by only attempting a simple conversion for non-direct 3725 // bindings) and p3's strange wording, we allow a const volatile 3726 // reference to bind to an rvalue. Hence the check for the presence 3727 // of "const" rather than checking for "const" being the only 3728 // qualifier. 3729 // This is also the point where rvalue references and lvalue inits no longer 3730 // go together. 3731 if (!isRValRef && !T1.isConstQualified()) 3732 return ICS; 3733 3734 // -- If the initializer expression 3735 // 3736 // -- is an xvalue, class prvalue, array prvalue or function 3737 // lvalue and "cv1 T1" is reference-compatible with "cv2 T2", or 3738 if (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification && 3739 (InitCategory.isXValue() || 3740 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) || 3741 (InitCategory.isLValue() && T2->isFunctionType()))) { 3742 ICS.setStandard(); 3743 ICS.Standard.First = ICK_Identity; 3744 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3745 : ObjCConversion? ICK_Compatible_Conversion 3746 : ICK_Identity; 3747 ICS.Standard.Third = ICK_Identity; 3748 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3749 ICS.Standard.setToType(0, T2); 3750 ICS.Standard.setToType(1, T1); 3751 ICS.Standard.setToType(2, T1); 3752 ICS.Standard.ReferenceBinding = true; 3753 // In C++0x, this is always a direct binding. In C++98/03, it's a direct 3754 // binding unless we're binding to a class prvalue. 3755 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we 3756 // allow the use of rvalue references in C++98/03 for the benefit of 3757 // standard library implementors; therefore, we need the xvalue check here. 3758 ICS.Standard.DirectBinding = 3759 S.getLangOptions().CPlusPlus0x || 3760 (InitCategory.isPRValue() && !T2->isRecordType()); 3761 ICS.Standard.IsLvalueReference = !isRValRef; 3762 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3763 ICS.Standard.BindsToRvalue = InitCategory.isRValue(); 3764 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3765 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion; 3766 ICS.Standard.CopyConstructor = 0; 3767 return ICS; 3768 } 3769 3770 // -- has a class type (i.e., T2 is a class type), where T1 is not 3771 // reference-related to T2, and can be implicitly converted to 3772 // an xvalue, class prvalue, or function lvalue of type 3773 // "cv3 T3", where "cv1 T1" is reference-compatible with 3774 // "cv3 T3", 3775 // 3776 // then the reference is bound to the value of the initializer 3777 // expression in the first case and to the result of the conversion 3778 // in the second case (or, in either case, to an appropriate base 3779 // class subobject). 3780 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3781 T2->isRecordType() && !S.RequireCompleteType(DeclLoc, T2, 0) && 3782 FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3783 Init, T2, /*AllowRvalues=*/true, 3784 AllowExplicit)) { 3785 // In the second case, if the reference is an rvalue reference 3786 // and the second standard conversion sequence of the 3787 // user-defined conversion sequence includes an lvalue-to-rvalue 3788 // conversion, the program is ill-formed. 3789 if (ICS.isUserDefined() && isRValRef && 3790 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue) 3791 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3792 3793 return ICS; 3794 } 3795 3796 // -- Otherwise, a temporary of type "cv1 T1" is created and 3797 // initialized from the initializer expression using the 3798 // rules for a non-reference copy initialization (8.5). The 3799 // reference is then bound to the temporary. If T1 is 3800 // reference-related to T2, cv1 must be the same 3801 // cv-qualification as, or greater cv-qualification than, 3802 // cv2; otherwise, the program is ill-formed. 3803 if (RefRelationship == Sema::Ref_Related) { 3804 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 3805 // we would be reference-compatible or reference-compatible with 3806 // added qualification. But that wasn't the case, so the reference 3807 // initialization fails. 3808 // 3809 // Note that we only want to check address spaces and cvr-qualifiers here. 3810 // ObjC GC and lifetime qualifiers aren't important. 3811 Qualifiers T1Quals = T1.getQualifiers(); 3812 Qualifiers T2Quals = T2.getQualifiers(); 3813 T1Quals.removeObjCGCAttr(); 3814 T1Quals.removeObjCLifetime(); 3815 T2Quals.removeObjCGCAttr(); 3816 T2Quals.removeObjCLifetime(); 3817 if (!T1Quals.compatiblyIncludes(T2Quals)) 3818 return ICS; 3819 } 3820 3821 // If at least one of the types is a class type, the types are not 3822 // related, and we aren't allowed any user conversions, the 3823 // reference binding fails. This case is important for breaking 3824 // recursion, since TryImplicitConversion below will attempt to 3825 // create a temporary through the use of a copy constructor. 3826 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3827 (T1->isRecordType() || T2->isRecordType())) 3828 return ICS; 3829 3830 // If T1 is reference-related to T2 and the reference is an rvalue 3831 // reference, the initializer expression shall not be an lvalue. 3832 if (RefRelationship >= Sema::Ref_Related && 3833 isRValRef && Init->Classify(S.Context).isLValue()) 3834 return ICS; 3835 3836 // C++ [over.ics.ref]p2: 3837 // When a parameter of reference type is not bound directly to 3838 // an argument expression, the conversion sequence is the one 3839 // required to convert the argument expression to the 3840 // underlying type of the reference according to 3841 // 13.3.3.1. Conceptually, this conversion sequence corresponds 3842 // to copy-initializing a temporary of the underlying type with 3843 // the argument expression. Any difference in top-level 3844 // cv-qualification is subsumed by the initialization itself 3845 // and does not constitute a conversion. 3846 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions, 3847 /*AllowExplicit=*/false, 3848 /*InOverloadResolution=*/false, 3849 /*CStyle=*/false, 3850 /*AllowObjCWritebackConversion=*/false); 3851 3852 // Of course, that's still a reference binding. 3853 if (ICS.isStandard()) { 3854 ICS.Standard.ReferenceBinding = true; 3855 ICS.Standard.IsLvalueReference = !isRValRef; 3856 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3857 ICS.Standard.BindsToRvalue = true; 3858 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3859 ICS.Standard.ObjCLifetimeConversionBinding = false; 3860 } else if (ICS.isUserDefined()) { 3861 // Don't allow rvalue references to bind to lvalues. 3862 if (DeclType->isRValueReferenceType()) { 3863 if (const ReferenceType *RefType 3864 = ICS.UserDefined.ConversionFunction->getResultType() 3865 ->getAs<LValueReferenceType>()) { 3866 if (!RefType->getPointeeType()->isFunctionType()) { 3867 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, Init, 3868 DeclType); 3869 return ICS; 3870 } 3871 } 3872 } 3873 3874 ICS.UserDefined.After.ReferenceBinding = true; 3875 ICS.UserDefined.After.IsLvalueReference = !isRValRef; 3876 ICS.UserDefined.After.BindsToFunctionLvalue = T2->isFunctionType(); 3877 ICS.UserDefined.After.BindsToRvalue = true; 3878 ICS.UserDefined.After.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3879 ICS.UserDefined.After.ObjCLifetimeConversionBinding = false; 3880 } 3881 3882 return ICS; 3883} 3884 3885static ImplicitConversionSequence 3886TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 3887 bool SuppressUserConversions, 3888 bool InOverloadResolution, 3889 bool AllowObjCWritebackConversion); 3890 3891/// TryListConversion - Try to copy-initialize a value of type ToType from the 3892/// initializer list From. 3893static ImplicitConversionSequence 3894TryListConversion(Sema &S, InitListExpr *From, QualType ToType, 3895 bool SuppressUserConversions, 3896 bool InOverloadResolution, 3897 bool AllowObjCWritebackConversion) { 3898 // C++11 [over.ics.list]p1: 3899 // When an argument is an initializer list, it is not an expression and 3900 // special rules apply for converting it to a parameter type. 3901 3902 ImplicitConversionSequence Result; 3903 Result.setBad(BadConversionSequence::no_conversion, From, ToType); 3904 Result.setListInitializationSequence(); 3905 3906 // C++11 [over.ics.list]p2: 3907 // If the parameter type is std::initializer_list<X> or "array of X" and 3908 // all the elements can be implicitly converted to X, the implicit 3909 // conversion sequence is the worst conversion necessary to convert an 3910 // element of the list to X. 3911 // FIXME: Recognize std::initializer_list. 3912 // FIXME: Arrays don't make sense until we can deal with references. 3913 if (ToType->isArrayType()) 3914 return Result; 3915 3916 // C++11 [over.ics.list]p3: 3917 // Otherwise, if the parameter is a non-aggregate class X and overload 3918 // resolution chooses a single best constructor [...] the implicit 3919 // conversion sequence is a user-defined conversion sequence. If multiple 3920 // constructors are viable but none is better than the others, the 3921 // implicit conversion sequence is a user-defined conversion sequence. 3922 // FIXME: Implement this. 3923 if (ToType->isRecordType() && !ToType->isAggregateType()) 3924 return Result; 3925 3926 // C++11 [over.ics.list]p4: 3927 // Otherwise, if the parameter has an aggregate type which can be 3928 // initialized from the initializer list [...] the implicit conversion 3929 // sequence is a user-defined conversion sequence. 3930 if (ToType->isAggregateType()) { 3931 // Type is an aggregate, argument is an init list. At this point it comes 3932 // down to checking whether the initialization works. 3933 // FIXME: Find out whether this parameter is consumed or not. 3934 InitializedEntity Entity = 3935 InitializedEntity::InitializeParameter(S.Context, ToType, 3936 /*Consumed=*/false); 3937 if (S.CanPerformCopyInitialization(Entity, S.Owned(From))) { 3938 Result.setUserDefined(); 3939 Result.UserDefined.Before.setAsIdentityConversion(); 3940 // Initializer lists don't have a type. 3941 Result.UserDefined.Before.setFromType(QualType()); 3942 Result.UserDefined.Before.setAllToTypes(QualType()); 3943 3944 Result.UserDefined.After.setAsIdentityConversion(); 3945 Result.UserDefined.After.setFromType(ToType); 3946 Result.UserDefined.After.setAllToTypes(ToType); 3947 } 3948 return Result; 3949 } 3950 3951 // C++11 [over.ics.list]p5: 3952 // Otherwise, if the parameter is a reference, see 13.3.3.1.4. 3953 // FIXME: Implement this. 3954 if (ToType->isReferenceType()) 3955 return Result; 3956 3957 // C++11 [over.ics.list]p6: 3958 // Otherwise, if the parameter type is not a class: 3959 if (!ToType->isRecordType()) { 3960 // - if the initializer list has one element, the implicit conversion 3961 // sequence is the one required to convert the element to the 3962 // parameter type. 3963 // FIXME: Catch narrowing here? 3964 unsigned NumInits = From->getNumInits(); 3965 if (NumInits == 1) 3966 Result = TryCopyInitialization(S, From->getInit(0), ToType, 3967 SuppressUserConversions, 3968 InOverloadResolution, 3969 AllowObjCWritebackConversion); 3970 // - if the initializer list has no elements, the implicit conversion 3971 // sequence is the identity conversion. 3972 else if (NumInits == 0) { 3973 Result.setStandard(); 3974 Result.Standard.setAsIdentityConversion(); 3975 } 3976 return Result; 3977 } 3978 3979 // C++11 [over.ics.list]p7: 3980 // In all cases other than those enumerated above, no conversion is possible 3981 return Result; 3982} 3983 3984/// TryCopyInitialization - Try to copy-initialize a value of type 3985/// ToType from the expression From. Return the implicit conversion 3986/// sequence required to pass this argument, which may be a bad 3987/// conversion sequence (meaning that the argument cannot be passed to 3988/// a parameter of this type). If @p SuppressUserConversions, then we 3989/// do not permit any user-defined conversion sequences. 3990static ImplicitConversionSequence 3991TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 3992 bool SuppressUserConversions, 3993 bool InOverloadResolution, 3994 bool AllowObjCWritebackConversion) { 3995 if (InitListExpr *FromInitList = dyn_cast<InitListExpr>(From)) 3996 return TryListConversion(S, FromInitList, ToType, SuppressUserConversions, 3997 InOverloadResolution,AllowObjCWritebackConversion); 3998 3999 if (ToType->isReferenceType()) 4000 return TryReferenceInit(S, From, ToType, 4001 /*FIXME:*/From->getLocStart(), 4002 SuppressUserConversions, 4003 /*AllowExplicit=*/false); 4004 4005 return TryImplicitConversion(S, From, ToType, 4006 SuppressUserConversions, 4007 /*AllowExplicit=*/false, 4008 InOverloadResolution, 4009 /*CStyle=*/false, 4010 AllowObjCWritebackConversion); 4011} 4012 4013static bool TryCopyInitialization(const CanQualType FromQTy, 4014 const CanQualType ToQTy, 4015 Sema &S, 4016 SourceLocation Loc, 4017 ExprValueKind FromVK) { 4018 OpaqueValueExpr TmpExpr(Loc, FromQTy, FromVK); 4019 ImplicitConversionSequence ICS = 4020 TryCopyInitialization(S, &TmpExpr, ToQTy, true, true, false); 4021 4022 return !ICS.isBad(); 4023} 4024 4025/// TryObjectArgumentInitialization - Try to initialize the object 4026/// parameter of the given member function (@c Method) from the 4027/// expression @p From. 4028static ImplicitConversionSequence 4029TryObjectArgumentInitialization(Sema &S, QualType OrigFromType, 4030 Expr::Classification FromClassification, 4031 CXXMethodDecl *Method, 4032 CXXRecordDecl *ActingContext) { 4033 QualType ClassType = S.Context.getTypeDeclType(ActingContext); 4034 // [class.dtor]p2: A destructor can be invoked for a const, volatile or 4035 // const volatile object. 4036 unsigned Quals = isa<CXXDestructorDecl>(Method) ? 4037 Qualifiers::Const | Qualifiers::Volatile : Method->getTypeQualifiers(); 4038 QualType ImplicitParamType = S.Context.getCVRQualifiedType(ClassType, Quals); 4039 4040 // Set up the conversion sequence as a "bad" conversion, to allow us 4041 // to exit early. 4042 ImplicitConversionSequence ICS; 4043 4044 // We need to have an object of class type. 4045 QualType FromType = OrigFromType; 4046 if (const PointerType *PT = FromType->getAs<PointerType>()) { 4047 FromType = PT->getPointeeType(); 4048 4049 // When we had a pointer, it's implicitly dereferenced, so we 4050 // better have an lvalue. 4051 assert(FromClassification.isLValue()); 4052 } 4053 4054 assert(FromType->isRecordType()); 4055 4056 // C++0x [over.match.funcs]p4: 4057 // For non-static member functions, the type of the implicit object 4058 // parameter is 4059 // 4060 // - "lvalue reference to cv X" for functions declared without a 4061 // ref-qualifier or with the & ref-qualifier 4062 // - "rvalue reference to cv X" for functions declared with the && 4063 // ref-qualifier 4064 // 4065 // where X is the class of which the function is a member and cv is the 4066 // cv-qualification on the member function declaration. 4067 // 4068 // However, when finding an implicit conversion sequence for the argument, we 4069 // are not allowed to create temporaries or perform user-defined conversions 4070 // (C++ [over.match.funcs]p5). We perform a simplified version of 4071 // reference binding here, that allows class rvalues to bind to 4072 // non-constant references. 4073 4074 // First check the qualifiers. 4075 QualType FromTypeCanon = S.Context.getCanonicalType(FromType); 4076 if (ImplicitParamType.getCVRQualifiers() 4077 != FromTypeCanon.getLocalCVRQualifiers() && 4078 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) { 4079 ICS.setBad(BadConversionSequence::bad_qualifiers, 4080 OrigFromType, ImplicitParamType); 4081 return ICS; 4082 } 4083 4084 // Check that we have either the same type or a derived type. It 4085 // affects the conversion rank. 4086 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType); 4087 ImplicitConversionKind SecondKind; 4088 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) { 4089 SecondKind = ICK_Identity; 4090 } else if (S.IsDerivedFrom(FromType, ClassType)) 4091 SecondKind = ICK_Derived_To_Base; 4092 else { 4093 ICS.setBad(BadConversionSequence::unrelated_class, 4094 FromType, ImplicitParamType); 4095 return ICS; 4096 } 4097 4098 // Check the ref-qualifier. 4099 switch (Method->getRefQualifier()) { 4100 case RQ_None: 4101 // Do nothing; we don't care about lvalueness or rvalueness. 4102 break; 4103 4104 case RQ_LValue: 4105 if (!FromClassification.isLValue() && Quals != Qualifiers::Const) { 4106 // non-const lvalue reference cannot bind to an rvalue 4107 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType, 4108 ImplicitParamType); 4109 return ICS; 4110 } 4111 break; 4112 4113 case RQ_RValue: 4114 if (!FromClassification.isRValue()) { 4115 // rvalue reference cannot bind to an lvalue 4116 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType, 4117 ImplicitParamType); 4118 return ICS; 4119 } 4120 break; 4121 } 4122 4123 // Success. Mark this as a reference binding. 4124 ICS.setStandard(); 4125 ICS.Standard.setAsIdentityConversion(); 4126 ICS.Standard.Second = SecondKind; 4127 ICS.Standard.setFromType(FromType); 4128 ICS.Standard.setAllToTypes(ImplicitParamType); 4129 ICS.Standard.ReferenceBinding = true; 4130 ICS.Standard.DirectBinding = true; 4131 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue; 4132 ICS.Standard.BindsToFunctionLvalue = false; 4133 ICS.Standard.BindsToRvalue = FromClassification.isRValue(); 4134 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier 4135 = (Method->getRefQualifier() == RQ_None); 4136 return ICS; 4137} 4138 4139/// PerformObjectArgumentInitialization - Perform initialization of 4140/// the implicit object parameter for the given Method with the given 4141/// expression. 4142ExprResult 4143Sema::PerformObjectArgumentInitialization(Expr *From, 4144 NestedNameSpecifier *Qualifier, 4145 NamedDecl *FoundDecl, 4146 CXXMethodDecl *Method) { 4147 QualType FromRecordType, DestType; 4148 QualType ImplicitParamRecordType = 4149 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType(); 4150 4151 Expr::Classification FromClassification; 4152 if (const PointerType *PT = From->getType()->getAs<PointerType>()) { 4153 FromRecordType = PT->getPointeeType(); 4154 DestType = Method->getThisType(Context); 4155 FromClassification = Expr::Classification::makeSimpleLValue(); 4156 } else { 4157 FromRecordType = From->getType(); 4158 DestType = ImplicitParamRecordType; 4159 FromClassification = From->Classify(Context); 4160 } 4161 4162 // Note that we always use the true parent context when performing 4163 // the actual argument initialization. 4164 ImplicitConversionSequence ICS 4165 = TryObjectArgumentInitialization(*this, From->getType(), FromClassification, 4166 Method, Method->getParent()); 4167 if (ICS.isBad()) { 4168 if (ICS.Bad.Kind == BadConversionSequence::bad_qualifiers) { 4169 Qualifiers FromQs = FromRecordType.getQualifiers(); 4170 Qualifiers ToQs = DestType.getQualifiers(); 4171 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 4172 if (CVR) { 4173 Diag(From->getSourceRange().getBegin(), 4174 diag::err_member_function_call_bad_cvr) 4175 << Method->getDeclName() << FromRecordType << (CVR - 1) 4176 << From->getSourceRange(); 4177 Diag(Method->getLocation(), diag::note_previous_decl) 4178 << Method->getDeclName(); 4179 return ExprError(); 4180 } 4181 } 4182 4183 return Diag(From->getSourceRange().getBegin(), 4184 diag::err_implicit_object_parameter_init) 4185 << ImplicitParamRecordType << FromRecordType << From->getSourceRange(); 4186 } 4187 4188 if (ICS.Standard.Second == ICK_Derived_To_Base) { 4189 ExprResult FromRes = 4190 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method); 4191 if (FromRes.isInvalid()) 4192 return ExprError(); 4193 From = FromRes.take(); 4194 } 4195 4196 if (!Context.hasSameType(From->getType(), DestType)) 4197 From = ImpCastExprToType(From, DestType, CK_NoOp, 4198 From->getValueKind()).take(); 4199 return Owned(From); 4200} 4201 4202/// TryContextuallyConvertToBool - Attempt to contextually convert the 4203/// expression From to bool (C++0x [conv]p3). 4204static ImplicitConversionSequence 4205TryContextuallyConvertToBool(Sema &S, Expr *From) { 4206 // FIXME: This is pretty broken. 4207 return TryImplicitConversion(S, From, S.Context.BoolTy, 4208 // FIXME: Are these flags correct? 4209 /*SuppressUserConversions=*/false, 4210 /*AllowExplicit=*/true, 4211 /*InOverloadResolution=*/false, 4212 /*CStyle=*/false, 4213 /*AllowObjCWritebackConversion=*/false); 4214} 4215 4216/// PerformContextuallyConvertToBool - Perform a contextual conversion 4217/// of the expression From to bool (C++0x [conv]p3). 4218ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) { 4219 if (checkPlaceholderForOverload(*this, From)) 4220 return ExprError(); 4221 4222 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From); 4223 if (!ICS.isBad()) 4224 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting); 4225 4226 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy)) 4227 return Diag(From->getSourceRange().getBegin(), 4228 diag::err_typecheck_bool_condition) 4229 << From->getType() << From->getSourceRange(); 4230 return ExprError(); 4231} 4232 4233/// dropPointerConversions - If the given standard conversion sequence 4234/// involves any pointer conversions, remove them. This may change 4235/// the result type of the conversion sequence. 4236static void dropPointerConversion(StandardConversionSequence &SCS) { 4237 if (SCS.Second == ICK_Pointer_Conversion) { 4238 SCS.Second = ICK_Identity; 4239 SCS.Third = ICK_Identity; 4240 SCS.ToTypePtrs[2] = SCS.ToTypePtrs[1] = SCS.ToTypePtrs[0]; 4241 } 4242} 4243 4244/// TryContextuallyConvertToObjCPointer - Attempt to contextually 4245/// convert the expression From to an Objective-C pointer type. 4246static ImplicitConversionSequence 4247TryContextuallyConvertToObjCPointer(Sema &S, Expr *From) { 4248 // Do an implicit conversion to 'id'. 4249 QualType Ty = S.Context.getObjCIdType(); 4250 ImplicitConversionSequence ICS 4251 = TryImplicitConversion(S, From, Ty, 4252 // FIXME: Are these flags correct? 4253 /*SuppressUserConversions=*/false, 4254 /*AllowExplicit=*/true, 4255 /*InOverloadResolution=*/false, 4256 /*CStyle=*/false, 4257 /*AllowObjCWritebackConversion=*/false); 4258 4259 // Strip off any final conversions to 'id'. 4260 switch (ICS.getKind()) { 4261 case ImplicitConversionSequence::BadConversion: 4262 case ImplicitConversionSequence::AmbiguousConversion: 4263 case ImplicitConversionSequence::EllipsisConversion: 4264 break; 4265 4266 case ImplicitConversionSequence::UserDefinedConversion: 4267 dropPointerConversion(ICS.UserDefined.After); 4268 break; 4269 4270 case ImplicitConversionSequence::StandardConversion: 4271 dropPointerConversion(ICS.Standard); 4272 break; 4273 } 4274 4275 return ICS; 4276} 4277 4278/// PerformContextuallyConvertToObjCPointer - Perform a contextual 4279/// conversion of the expression From to an Objective-C pointer type. 4280ExprResult Sema::PerformContextuallyConvertToObjCPointer(Expr *From) { 4281 if (checkPlaceholderForOverload(*this, From)) 4282 return ExprError(); 4283 4284 QualType Ty = Context.getObjCIdType(); 4285 ImplicitConversionSequence ICS = 4286 TryContextuallyConvertToObjCPointer(*this, From); 4287 if (!ICS.isBad()) 4288 return PerformImplicitConversion(From, Ty, ICS, AA_Converting); 4289 return ExprError(); 4290} 4291 4292/// \brief Attempt to convert the given expression to an integral or 4293/// enumeration type. 4294/// 4295/// This routine will attempt to convert an expression of class type to an 4296/// integral or enumeration type, if that class type only has a single 4297/// conversion to an integral or enumeration type. 4298/// 4299/// \param Loc The source location of the construct that requires the 4300/// conversion. 4301/// 4302/// \param FromE The expression we're converting from. 4303/// 4304/// \param NotIntDiag The diagnostic to be emitted if the expression does not 4305/// have integral or enumeration type. 4306/// 4307/// \param IncompleteDiag The diagnostic to be emitted if the expression has 4308/// incomplete class type. 4309/// 4310/// \param ExplicitConvDiag The diagnostic to be emitted if we're calling an 4311/// explicit conversion function (because no implicit conversion functions 4312/// were available). This is a recovery mode. 4313/// 4314/// \param ExplicitConvNote The note to be emitted with \p ExplicitConvDiag, 4315/// showing which conversion was picked. 4316/// 4317/// \param AmbigDiag The diagnostic to be emitted if there is more than one 4318/// conversion function that could convert to integral or enumeration type. 4319/// 4320/// \param AmbigNote The note to be emitted with \p AmbigDiag for each 4321/// usable conversion function. 4322/// 4323/// \param ConvDiag The diagnostic to be emitted if we are calling a conversion 4324/// function, which may be an extension in this case. 4325/// 4326/// \returns The expression, converted to an integral or enumeration type if 4327/// successful. 4328ExprResult 4329Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From, 4330 const PartialDiagnostic &NotIntDiag, 4331 const PartialDiagnostic &IncompleteDiag, 4332 const PartialDiagnostic &ExplicitConvDiag, 4333 const PartialDiagnostic &ExplicitConvNote, 4334 const PartialDiagnostic &AmbigDiag, 4335 const PartialDiagnostic &AmbigNote, 4336 const PartialDiagnostic &ConvDiag) { 4337 // We can't perform any more checking for type-dependent expressions. 4338 if (From->isTypeDependent()) 4339 return Owned(From); 4340 4341 // If the expression already has integral or enumeration type, we're golden. 4342 QualType T = From->getType(); 4343 if (T->isIntegralOrEnumerationType()) 4344 return Owned(From); 4345 4346 // FIXME: Check for missing '()' if T is a function type? 4347 4348 // If we don't have a class type in C++, there's no way we can get an 4349 // expression of integral or enumeration type. 4350 const RecordType *RecordTy = T->getAs<RecordType>(); 4351 if (!RecordTy || !getLangOptions().CPlusPlus) { 4352 Diag(Loc, NotIntDiag) 4353 << T << From->getSourceRange(); 4354 return Owned(From); 4355 } 4356 4357 // We must have a complete class type. 4358 if (RequireCompleteType(Loc, T, IncompleteDiag)) 4359 return Owned(From); 4360 4361 // Look for a conversion to an integral or enumeration type. 4362 UnresolvedSet<4> ViableConversions; 4363 UnresolvedSet<4> ExplicitConversions; 4364 const UnresolvedSetImpl *Conversions 4365 = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions(); 4366 4367 bool HadMultipleCandidates = (Conversions->size() > 1); 4368 4369 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 4370 E = Conversions->end(); 4371 I != E; 4372 ++I) { 4373 if (CXXConversionDecl *Conversion 4374 = dyn_cast<CXXConversionDecl>((*I)->getUnderlyingDecl())) 4375 if (Conversion->getConversionType().getNonReferenceType() 4376 ->isIntegralOrEnumerationType()) { 4377 if (Conversion->isExplicit()) 4378 ExplicitConversions.addDecl(I.getDecl(), I.getAccess()); 4379 else 4380 ViableConversions.addDecl(I.getDecl(), I.getAccess()); 4381 } 4382 } 4383 4384 switch (ViableConversions.size()) { 4385 case 0: 4386 if (ExplicitConversions.size() == 1) { 4387 DeclAccessPair Found = ExplicitConversions[0]; 4388 CXXConversionDecl *Conversion 4389 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 4390 4391 // The user probably meant to invoke the given explicit 4392 // conversion; use it. 4393 QualType ConvTy 4394 = Conversion->getConversionType().getNonReferenceType(); 4395 std::string TypeStr; 4396 ConvTy.getAsStringInternal(TypeStr, getPrintingPolicy()); 4397 4398 Diag(Loc, ExplicitConvDiag) 4399 << T << ConvTy 4400 << FixItHint::CreateInsertion(From->getLocStart(), 4401 "static_cast<" + TypeStr + ">(") 4402 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(From->getLocEnd()), 4403 ")"); 4404 Diag(Conversion->getLocation(), ExplicitConvNote) 4405 << ConvTy->isEnumeralType() << ConvTy; 4406 4407 // If we aren't in a SFINAE context, build a call to the 4408 // explicit conversion function. 4409 if (isSFINAEContext()) 4410 return ExprError(); 4411 4412 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 4413 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion, 4414 HadMultipleCandidates); 4415 if (Result.isInvalid()) 4416 return ExprError(); 4417 // Record usage of conversion in an implicit cast. 4418 From = ImplicitCastExpr::Create(Context, Result.get()->getType(), 4419 CK_UserDefinedConversion, 4420 Result.get(), 0, 4421 Result.get()->getValueKind()); 4422 } 4423 4424 // We'll complain below about a non-integral condition type. 4425 break; 4426 4427 case 1: { 4428 // Apply this conversion. 4429 DeclAccessPair Found = ViableConversions[0]; 4430 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 4431 4432 CXXConversionDecl *Conversion 4433 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 4434 QualType ConvTy 4435 = Conversion->getConversionType().getNonReferenceType(); 4436 if (ConvDiag.getDiagID()) { 4437 if (isSFINAEContext()) 4438 return ExprError(); 4439 4440 Diag(Loc, ConvDiag) 4441 << T << ConvTy->isEnumeralType() << ConvTy << From->getSourceRange(); 4442 } 4443 4444 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion, 4445 HadMultipleCandidates); 4446 if (Result.isInvalid()) 4447 return ExprError(); 4448 // Record usage of conversion in an implicit cast. 4449 From = ImplicitCastExpr::Create(Context, Result.get()->getType(), 4450 CK_UserDefinedConversion, 4451 Result.get(), 0, 4452 Result.get()->getValueKind()); 4453 break; 4454 } 4455 4456 default: 4457 Diag(Loc, AmbigDiag) 4458 << T << From->getSourceRange(); 4459 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { 4460 CXXConversionDecl *Conv 4461 = cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl()); 4462 QualType ConvTy = Conv->getConversionType().getNonReferenceType(); 4463 Diag(Conv->getLocation(), AmbigNote) 4464 << ConvTy->isEnumeralType() << ConvTy; 4465 } 4466 return Owned(From); 4467 } 4468 4469 if (!From->getType()->isIntegralOrEnumerationType()) 4470 Diag(Loc, NotIntDiag) 4471 << From->getType() << From->getSourceRange(); 4472 4473 return Owned(From); 4474} 4475 4476/// AddOverloadCandidate - Adds the given function to the set of 4477/// candidate functions, using the given function call arguments. If 4478/// @p SuppressUserConversions, then don't allow user-defined 4479/// conversions via constructors or conversion operators. 4480/// 4481/// \para PartialOverloading true if we are performing "partial" overloading 4482/// based on an incomplete set of function arguments. This feature is used by 4483/// code completion. 4484void 4485Sema::AddOverloadCandidate(FunctionDecl *Function, 4486 DeclAccessPair FoundDecl, 4487 Expr **Args, unsigned NumArgs, 4488 OverloadCandidateSet& CandidateSet, 4489 bool SuppressUserConversions, 4490 bool PartialOverloading) { 4491 const FunctionProtoType* Proto 4492 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>()); 4493 assert(Proto && "Functions without a prototype cannot be overloaded"); 4494 assert(!Function->getDescribedFunctionTemplate() && 4495 "Use AddTemplateOverloadCandidate for function templates"); 4496 4497 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 4498 if (!isa<CXXConstructorDecl>(Method)) { 4499 // If we get here, it's because we're calling a member function 4500 // that is named without a member access expression (e.g., 4501 // "this->f") that was either written explicitly or created 4502 // implicitly. This can happen with a qualified call to a member 4503 // function, e.g., X::f(). We use an empty type for the implied 4504 // object argument (C++ [over.call.func]p3), and the acting context 4505 // is irrelevant. 4506 AddMethodCandidate(Method, FoundDecl, Method->getParent(), 4507 QualType(), Expr::Classification::makeSimpleLValue(), 4508 Args, NumArgs, CandidateSet, 4509 SuppressUserConversions); 4510 return; 4511 } 4512 // We treat a constructor like a non-member function, since its object 4513 // argument doesn't participate in overload resolution. 4514 } 4515 4516 if (!CandidateSet.isNewCandidate(Function)) 4517 return; 4518 4519 // Overload resolution is always an unevaluated context. 4520 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4521 4522 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function)){ 4523 // C++ [class.copy]p3: 4524 // A member function template is never instantiated to perform the copy 4525 // of a class object to an object of its class type. 4526 QualType ClassType = Context.getTypeDeclType(Constructor->getParent()); 4527 if (NumArgs == 1 && 4528 Constructor->isSpecializationCopyingObject() && 4529 (Context.hasSameUnqualifiedType(ClassType, Args[0]->getType()) || 4530 IsDerivedFrom(Args[0]->getType(), ClassType))) 4531 return; 4532 } 4533 4534 // Add this candidate 4535 CandidateSet.push_back(OverloadCandidate()); 4536 OverloadCandidate& Candidate = CandidateSet.back(); 4537 Candidate.FoundDecl = FoundDecl; 4538 Candidate.Function = Function; 4539 Candidate.Viable = true; 4540 Candidate.IsSurrogate = false; 4541 Candidate.IgnoreObjectArgument = false; 4542 Candidate.ExplicitCallArguments = NumArgs; 4543 4544 unsigned NumArgsInProto = Proto->getNumArgs(); 4545 4546 // (C++ 13.3.2p2): A candidate function having fewer than m 4547 // parameters is viable only if it has an ellipsis in its parameter 4548 // list (8.3.5). 4549 if ((NumArgs + (PartialOverloading && NumArgs)) > NumArgsInProto && 4550 !Proto->isVariadic()) { 4551 Candidate.Viable = false; 4552 Candidate.FailureKind = ovl_fail_too_many_arguments; 4553 return; 4554 } 4555 4556 // (C++ 13.3.2p2): A candidate function having more than m parameters 4557 // is viable only if the (m+1)st parameter has a default argument 4558 // (8.3.6). For the purposes of overload resolution, the 4559 // parameter list is truncated on the right, so that there are 4560 // exactly m parameters. 4561 unsigned MinRequiredArgs = Function->getMinRequiredArguments(); 4562 if (NumArgs < MinRequiredArgs && !PartialOverloading) { 4563 // Not enough arguments. 4564 Candidate.Viable = false; 4565 Candidate.FailureKind = ovl_fail_too_few_arguments; 4566 return; 4567 } 4568 4569 // (CUDA B.1): Check for invalid calls between targets. 4570 if (getLangOptions().CUDA) 4571 if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext)) 4572 if (CheckCUDATarget(Caller, Function)) { 4573 Candidate.Viable = false; 4574 Candidate.FailureKind = ovl_fail_bad_target; 4575 return; 4576 } 4577 4578 // Determine the implicit conversion sequences for each of the 4579 // arguments. 4580 Candidate.Conversions.resize(NumArgs); 4581 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4582 if (ArgIdx < NumArgsInProto) { 4583 // (C++ 13.3.2p3): for F to be a viable function, there shall 4584 // exist for each argument an implicit conversion sequence 4585 // (13.3.3.1) that converts that argument to the corresponding 4586 // parameter of F. 4587 QualType ParamType = Proto->getArgType(ArgIdx); 4588 Candidate.Conversions[ArgIdx] 4589 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4590 SuppressUserConversions, 4591 /*InOverloadResolution=*/true, 4592 /*AllowObjCWritebackConversion=*/ 4593 getLangOptions().ObjCAutoRefCount); 4594 if (Candidate.Conversions[ArgIdx].isBad()) { 4595 Candidate.Viable = false; 4596 Candidate.FailureKind = ovl_fail_bad_conversion; 4597 break; 4598 } 4599 } else { 4600 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4601 // argument for which there is no corresponding parameter is 4602 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4603 Candidate.Conversions[ArgIdx].setEllipsis(); 4604 } 4605 } 4606} 4607 4608/// \brief Add all of the function declarations in the given function set to 4609/// the overload canddiate set. 4610void Sema::AddFunctionCandidates(const UnresolvedSetImpl &Fns, 4611 Expr **Args, unsigned NumArgs, 4612 OverloadCandidateSet& CandidateSet, 4613 bool SuppressUserConversions) { 4614 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) { 4615 NamedDecl *D = F.getDecl()->getUnderlyingDecl(); 4616 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 4617 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 4618 AddMethodCandidate(cast<CXXMethodDecl>(FD), F.getPair(), 4619 cast<CXXMethodDecl>(FD)->getParent(), 4620 Args[0]->getType(), Args[0]->Classify(Context), 4621 Args + 1, NumArgs - 1, 4622 CandidateSet, SuppressUserConversions); 4623 else 4624 AddOverloadCandidate(FD, F.getPair(), Args, NumArgs, CandidateSet, 4625 SuppressUserConversions); 4626 } else { 4627 FunctionTemplateDecl *FunTmpl = cast<FunctionTemplateDecl>(D); 4628 if (isa<CXXMethodDecl>(FunTmpl->getTemplatedDecl()) && 4629 !cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())->isStatic()) 4630 AddMethodTemplateCandidate(FunTmpl, F.getPair(), 4631 cast<CXXRecordDecl>(FunTmpl->getDeclContext()), 4632 /*FIXME: explicit args */ 0, 4633 Args[0]->getType(), 4634 Args[0]->Classify(Context), 4635 Args + 1, NumArgs - 1, 4636 CandidateSet, 4637 SuppressUserConversions); 4638 else 4639 AddTemplateOverloadCandidate(FunTmpl, F.getPair(), 4640 /*FIXME: explicit args */ 0, 4641 Args, NumArgs, CandidateSet, 4642 SuppressUserConversions); 4643 } 4644 } 4645} 4646 4647/// AddMethodCandidate - Adds a named decl (which is some kind of 4648/// method) as a method candidate to the given overload set. 4649void Sema::AddMethodCandidate(DeclAccessPair FoundDecl, 4650 QualType ObjectType, 4651 Expr::Classification ObjectClassification, 4652 Expr **Args, unsigned NumArgs, 4653 OverloadCandidateSet& CandidateSet, 4654 bool SuppressUserConversions) { 4655 NamedDecl *Decl = FoundDecl.getDecl(); 4656 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(Decl->getDeclContext()); 4657 4658 if (isa<UsingShadowDecl>(Decl)) 4659 Decl = cast<UsingShadowDecl>(Decl)->getTargetDecl(); 4660 4661 if (FunctionTemplateDecl *TD = dyn_cast<FunctionTemplateDecl>(Decl)) { 4662 assert(isa<CXXMethodDecl>(TD->getTemplatedDecl()) && 4663 "Expected a member function template"); 4664 AddMethodTemplateCandidate(TD, FoundDecl, ActingContext, 4665 /*ExplicitArgs*/ 0, 4666 ObjectType, ObjectClassification, Args, NumArgs, 4667 CandidateSet, 4668 SuppressUserConversions); 4669 } else { 4670 AddMethodCandidate(cast<CXXMethodDecl>(Decl), FoundDecl, ActingContext, 4671 ObjectType, ObjectClassification, Args, NumArgs, 4672 CandidateSet, SuppressUserConversions); 4673 } 4674} 4675 4676/// AddMethodCandidate - Adds the given C++ member function to the set 4677/// of candidate functions, using the given function call arguments 4678/// and the object argument (@c Object). For example, in a call 4679/// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain 4680/// both @c a1 and @c a2. If @p SuppressUserConversions, then don't 4681/// allow user-defined conversions via constructors or conversion 4682/// operators. 4683void 4684Sema::AddMethodCandidate(CXXMethodDecl *Method, DeclAccessPair FoundDecl, 4685 CXXRecordDecl *ActingContext, QualType ObjectType, 4686 Expr::Classification ObjectClassification, 4687 Expr **Args, unsigned NumArgs, 4688 OverloadCandidateSet& CandidateSet, 4689 bool SuppressUserConversions) { 4690 const FunctionProtoType* Proto 4691 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>()); 4692 assert(Proto && "Methods without a prototype cannot be overloaded"); 4693 assert(!isa<CXXConstructorDecl>(Method) && 4694 "Use AddOverloadCandidate for constructors"); 4695 4696 if (!CandidateSet.isNewCandidate(Method)) 4697 return; 4698 4699 // Overload resolution is always an unevaluated context. 4700 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4701 4702 // Add this candidate 4703 CandidateSet.push_back(OverloadCandidate()); 4704 OverloadCandidate& Candidate = CandidateSet.back(); 4705 Candidate.FoundDecl = FoundDecl; 4706 Candidate.Function = Method; 4707 Candidate.IsSurrogate = false; 4708 Candidate.IgnoreObjectArgument = false; 4709 Candidate.ExplicitCallArguments = NumArgs; 4710 4711 unsigned NumArgsInProto = Proto->getNumArgs(); 4712 4713 // (C++ 13.3.2p2): A candidate function having fewer than m 4714 // parameters is viable only if it has an ellipsis in its parameter 4715 // list (8.3.5). 4716 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4717 Candidate.Viable = false; 4718 Candidate.FailureKind = ovl_fail_too_many_arguments; 4719 return; 4720 } 4721 4722 // (C++ 13.3.2p2): A candidate function having more than m parameters 4723 // is viable only if the (m+1)st parameter has a default argument 4724 // (8.3.6). For the purposes of overload resolution, the 4725 // parameter list is truncated on the right, so that there are 4726 // exactly m parameters. 4727 unsigned MinRequiredArgs = Method->getMinRequiredArguments(); 4728 if (NumArgs < MinRequiredArgs) { 4729 // Not enough arguments. 4730 Candidate.Viable = false; 4731 Candidate.FailureKind = ovl_fail_too_few_arguments; 4732 return; 4733 } 4734 4735 Candidate.Viable = true; 4736 Candidate.Conversions.resize(NumArgs + 1); 4737 4738 if (Method->isStatic() || ObjectType.isNull()) 4739 // The implicit object argument is ignored. 4740 Candidate.IgnoreObjectArgument = true; 4741 else { 4742 // Determine the implicit conversion sequence for the object 4743 // parameter. 4744 Candidate.Conversions[0] 4745 = TryObjectArgumentInitialization(*this, ObjectType, ObjectClassification, 4746 Method, ActingContext); 4747 if (Candidate.Conversions[0].isBad()) { 4748 Candidate.Viable = false; 4749 Candidate.FailureKind = ovl_fail_bad_conversion; 4750 return; 4751 } 4752 } 4753 4754 // Determine the implicit conversion sequences for each of the 4755 // arguments. 4756 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4757 if (ArgIdx < NumArgsInProto) { 4758 // (C++ 13.3.2p3): for F to be a viable function, there shall 4759 // exist for each argument an implicit conversion sequence 4760 // (13.3.3.1) that converts that argument to the corresponding 4761 // parameter of F. 4762 QualType ParamType = Proto->getArgType(ArgIdx); 4763 Candidate.Conversions[ArgIdx + 1] 4764 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4765 SuppressUserConversions, 4766 /*InOverloadResolution=*/true, 4767 /*AllowObjCWritebackConversion=*/ 4768 getLangOptions().ObjCAutoRefCount); 4769 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4770 Candidate.Viable = false; 4771 Candidate.FailureKind = ovl_fail_bad_conversion; 4772 break; 4773 } 4774 } else { 4775 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4776 // argument for which there is no corresponding parameter is 4777 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4778 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4779 } 4780 } 4781} 4782 4783/// \brief Add a C++ member function template as a candidate to the candidate 4784/// set, using template argument deduction to produce an appropriate member 4785/// function template specialization. 4786void 4787Sema::AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl, 4788 DeclAccessPair FoundDecl, 4789 CXXRecordDecl *ActingContext, 4790 TemplateArgumentListInfo *ExplicitTemplateArgs, 4791 QualType ObjectType, 4792 Expr::Classification ObjectClassification, 4793 Expr **Args, unsigned NumArgs, 4794 OverloadCandidateSet& CandidateSet, 4795 bool SuppressUserConversions) { 4796 if (!CandidateSet.isNewCandidate(MethodTmpl)) 4797 return; 4798 4799 // C++ [over.match.funcs]p7: 4800 // In each case where a candidate is a function template, candidate 4801 // function template specializations are generated using template argument 4802 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4803 // candidate functions in the usual way.113) A given name can refer to one 4804 // or more function templates and also to a set of overloaded non-template 4805 // functions. In such a case, the candidate functions generated from each 4806 // function template are combined with the set of non-template candidate 4807 // functions. 4808 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4809 FunctionDecl *Specialization = 0; 4810 if (TemplateDeductionResult Result 4811 = DeduceTemplateArguments(MethodTmpl, ExplicitTemplateArgs, 4812 Args, NumArgs, Specialization, Info)) { 4813 CandidateSet.push_back(OverloadCandidate()); 4814 OverloadCandidate &Candidate = CandidateSet.back(); 4815 Candidate.FoundDecl = FoundDecl; 4816 Candidate.Function = MethodTmpl->getTemplatedDecl(); 4817 Candidate.Viable = false; 4818 Candidate.FailureKind = ovl_fail_bad_deduction; 4819 Candidate.IsSurrogate = false; 4820 Candidate.IgnoreObjectArgument = false; 4821 Candidate.ExplicitCallArguments = NumArgs; 4822 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4823 Info); 4824 return; 4825 } 4826 4827 // Add the function template specialization produced by template argument 4828 // deduction as a candidate. 4829 assert(Specialization && "Missing member function template specialization?"); 4830 assert(isa<CXXMethodDecl>(Specialization) && 4831 "Specialization is not a member function?"); 4832 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), FoundDecl, 4833 ActingContext, ObjectType, ObjectClassification, 4834 Args, NumArgs, CandidateSet, SuppressUserConversions); 4835} 4836 4837/// \brief Add a C++ function template specialization as a candidate 4838/// in the candidate set, using template argument deduction to produce 4839/// an appropriate function template specialization. 4840void 4841Sema::AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate, 4842 DeclAccessPair FoundDecl, 4843 TemplateArgumentListInfo *ExplicitTemplateArgs, 4844 Expr **Args, unsigned NumArgs, 4845 OverloadCandidateSet& CandidateSet, 4846 bool SuppressUserConversions) { 4847 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4848 return; 4849 4850 // C++ [over.match.funcs]p7: 4851 // In each case where a candidate is a function template, candidate 4852 // function template specializations are generated using template argument 4853 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4854 // candidate functions in the usual way.113) A given name can refer to one 4855 // or more function templates and also to a set of overloaded non-template 4856 // functions. In such a case, the candidate functions generated from each 4857 // function template are combined with the set of non-template candidate 4858 // functions. 4859 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4860 FunctionDecl *Specialization = 0; 4861 if (TemplateDeductionResult Result 4862 = DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, 4863 Args, NumArgs, Specialization, Info)) { 4864 CandidateSet.push_back(OverloadCandidate()); 4865 OverloadCandidate &Candidate = CandidateSet.back(); 4866 Candidate.FoundDecl = FoundDecl; 4867 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4868 Candidate.Viable = false; 4869 Candidate.FailureKind = ovl_fail_bad_deduction; 4870 Candidate.IsSurrogate = false; 4871 Candidate.IgnoreObjectArgument = false; 4872 Candidate.ExplicitCallArguments = NumArgs; 4873 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4874 Info); 4875 return; 4876 } 4877 4878 // Add the function template specialization produced by template argument 4879 // deduction as a candidate. 4880 assert(Specialization && "Missing function template specialization?"); 4881 AddOverloadCandidate(Specialization, FoundDecl, Args, NumArgs, CandidateSet, 4882 SuppressUserConversions); 4883} 4884 4885/// AddConversionCandidate - Add a C++ conversion function as a 4886/// candidate in the candidate set (C++ [over.match.conv], 4887/// C++ [over.match.copy]). From is the expression we're converting from, 4888/// and ToType is the type that we're eventually trying to convert to 4889/// (which may or may not be the same type as the type that the 4890/// conversion function produces). 4891void 4892Sema::AddConversionCandidate(CXXConversionDecl *Conversion, 4893 DeclAccessPair FoundDecl, 4894 CXXRecordDecl *ActingContext, 4895 Expr *From, QualType ToType, 4896 OverloadCandidateSet& CandidateSet) { 4897 assert(!Conversion->getDescribedFunctionTemplate() && 4898 "Conversion function templates use AddTemplateConversionCandidate"); 4899 QualType ConvType = Conversion->getConversionType().getNonReferenceType(); 4900 if (!CandidateSet.isNewCandidate(Conversion)) 4901 return; 4902 4903 // Overload resolution is always an unevaluated context. 4904 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4905 4906 // Add this candidate 4907 CandidateSet.push_back(OverloadCandidate()); 4908 OverloadCandidate& Candidate = CandidateSet.back(); 4909 Candidate.FoundDecl = FoundDecl; 4910 Candidate.Function = Conversion; 4911 Candidate.IsSurrogate = false; 4912 Candidate.IgnoreObjectArgument = false; 4913 Candidate.FinalConversion.setAsIdentityConversion(); 4914 Candidate.FinalConversion.setFromType(ConvType); 4915 Candidate.FinalConversion.setAllToTypes(ToType); 4916 Candidate.Viable = true; 4917 Candidate.Conversions.resize(1); 4918 Candidate.ExplicitCallArguments = 1; 4919 4920 // C++ [over.match.funcs]p4: 4921 // For conversion functions, the function is considered to be a member of 4922 // the class of the implicit implied object argument for the purpose of 4923 // defining the type of the implicit object parameter. 4924 // 4925 // Determine the implicit conversion sequence for the implicit 4926 // object parameter. 4927 QualType ImplicitParamType = From->getType(); 4928 if (const PointerType *FromPtrType = ImplicitParamType->getAs<PointerType>()) 4929 ImplicitParamType = FromPtrType->getPointeeType(); 4930 CXXRecordDecl *ConversionContext 4931 = cast<CXXRecordDecl>(ImplicitParamType->getAs<RecordType>()->getDecl()); 4932 4933 Candidate.Conversions[0] 4934 = TryObjectArgumentInitialization(*this, From->getType(), 4935 From->Classify(Context), 4936 Conversion, ConversionContext); 4937 4938 if (Candidate.Conversions[0].isBad()) { 4939 Candidate.Viable = false; 4940 Candidate.FailureKind = ovl_fail_bad_conversion; 4941 return; 4942 } 4943 4944 // We won't go through a user-define type conversion function to convert a 4945 // derived to base as such conversions are given Conversion Rank. They only 4946 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user] 4947 QualType FromCanon 4948 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 4949 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 4950 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 4951 Candidate.Viable = false; 4952 Candidate.FailureKind = ovl_fail_trivial_conversion; 4953 return; 4954 } 4955 4956 // To determine what the conversion from the result of calling the 4957 // conversion function to the type we're eventually trying to 4958 // convert to (ToType), we need to synthesize a call to the 4959 // conversion function and attempt copy initialization from it. This 4960 // makes sure that we get the right semantics with respect to 4961 // lvalues/rvalues and the type. Fortunately, we can allocate this 4962 // call on the stack and we don't need its arguments to be 4963 // well-formed. 4964 DeclRefExpr ConversionRef(Conversion, Conversion->getType(), 4965 VK_LValue, From->getLocStart()); 4966 ImplicitCastExpr ConversionFn(ImplicitCastExpr::OnStack, 4967 Context.getPointerType(Conversion->getType()), 4968 CK_FunctionToPointerDecay, 4969 &ConversionRef, VK_RValue); 4970 4971 QualType ConversionType = Conversion->getConversionType(); 4972 if (RequireCompleteType(From->getLocStart(), ConversionType, 0)) { 4973 Candidate.Viable = false; 4974 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4975 return; 4976 } 4977 4978 ExprValueKind VK = Expr::getValueKindForType(ConversionType); 4979 4980 // Note that it is safe to allocate CallExpr on the stack here because 4981 // there are 0 arguments (i.e., nothing is allocated using ASTContext's 4982 // allocator). 4983 QualType CallResultType = ConversionType.getNonLValueExprType(Context); 4984 CallExpr Call(Context, &ConversionFn, 0, 0, CallResultType, VK, 4985 From->getLocStart()); 4986 ImplicitConversionSequence ICS = 4987 TryCopyInitialization(*this, &Call, ToType, 4988 /*SuppressUserConversions=*/true, 4989 /*InOverloadResolution=*/false, 4990 /*AllowObjCWritebackConversion=*/false); 4991 4992 switch (ICS.getKind()) { 4993 case ImplicitConversionSequence::StandardConversion: 4994 Candidate.FinalConversion = ICS.Standard; 4995 4996 // C++ [over.ics.user]p3: 4997 // If the user-defined conversion is specified by a specialization of a 4998 // conversion function template, the second standard conversion sequence 4999 // shall have exact match rank. 5000 if (Conversion->getPrimaryTemplate() && 5001 GetConversionRank(ICS.Standard.Second) != ICR_Exact_Match) { 5002 Candidate.Viable = false; 5003 Candidate.FailureKind = ovl_fail_final_conversion_not_exact; 5004 } 5005 5006 // C++0x [dcl.init.ref]p5: 5007 // In the second case, if the reference is an rvalue reference and 5008 // the second standard conversion sequence of the user-defined 5009 // conversion sequence includes an lvalue-to-rvalue conversion, the 5010 // program is ill-formed. 5011 if (ToType->isRValueReferenceType() && 5012 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 5013 Candidate.Viable = false; 5014 Candidate.FailureKind = ovl_fail_bad_final_conversion; 5015 } 5016 break; 5017 5018 case ImplicitConversionSequence::BadConversion: 5019 Candidate.Viable = false; 5020 Candidate.FailureKind = ovl_fail_bad_final_conversion; 5021 break; 5022 5023 default: 5024 llvm_unreachable( 5025 "Can only end up with a standard conversion sequence or failure"); 5026 } 5027} 5028 5029/// \brief Adds a conversion function template specialization 5030/// candidate to the overload set, using template argument deduction 5031/// to deduce the template arguments of the conversion function 5032/// template from the type that we are converting to (C++ 5033/// [temp.deduct.conv]). 5034void 5035Sema::AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate, 5036 DeclAccessPair FoundDecl, 5037 CXXRecordDecl *ActingDC, 5038 Expr *From, QualType ToType, 5039 OverloadCandidateSet &CandidateSet) { 5040 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) && 5041 "Only conversion function templates permitted here"); 5042 5043 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 5044 return; 5045 5046 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 5047 CXXConversionDecl *Specialization = 0; 5048 if (TemplateDeductionResult Result 5049 = DeduceTemplateArguments(FunctionTemplate, ToType, 5050 Specialization, Info)) { 5051 CandidateSet.push_back(OverloadCandidate()); 5052 OverloadCandidate &Candidate = CandidateSet.back(); 5053 Candidate.FoundDecl = FoundDecl; 5054 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 5055 Candidate.Viable = false; 5056 Candidate.FailureKind = ovl_fail_bad_deduction; 5057 Candidate.IsSurrogate = false; 5058 Candidate.IgnoreObjectArgument = false; 5059 Candidate.ExplicitCallArguments = 1; 5060 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 5061 Info); 5062 return; 5063 } 5064 5065 // Add the conversion function template specialization produced by 5066 // template argument deduction as a candidate. 5067 assert(Specialization && "Missing function template specialization?"); 5068 AddConversionCandidate(Specialization, FoundDecl, ActingDC, From, ToType, 5069 CandidateSet); 5070} 5071 5072/// AddSurrogateCandidate - Adds a "surrogate" candidate function that 5073/// converts the given @c Object to a function pointer via the 5074/// conversion function @c Conversion, and then attempts to call it 5075/// with the given arguments (C++ [over.call.object]p2-4). Proto is 5076/// the type of function that we'll eventually be calling. 5077void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion, 5078 DeclAccessPair FoundDecl, 5079 CXXRecordDecl *ActingContext, 5080 const FunctionProtoType *Proto, 5081 Expr *Object, 5082 Expr **Args, unsigned NumArgs, 5083 OverloadCandidateSet& CandidateSet) { 5084 if (!CandidateSet.isNewCandidate(Conversion)) 5085 return; 5086 5087 // Overload resolution is always an unevaluated context. 5088 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 5089 5090 CandidateSet.push_back(OverloadCandidate()); 5091 OverloadCandidate& Candidate = CandidateSet.back(); 5092 Candidate.FoundDecl = FoundDecl; 5093 Candidate.Function = 0; 5094 Candidate.Surrogate = Conversion; 5095 Candidate.Viable = true; 5096 Candidate.IsSurrogate = true; 5097 Candidate.IgnoreObjectArgument = false; 5098 Candidate.Conversions.resize(NumArgs + 1); 5099 Candidate.ExplicitCallArguments = NumArgs; 5100 5101 // Determine the implicit conversion sequence for the implicit 5102 // object parameter. 5103 ImplicitConversionSequence ObjectInit 5104 = TryObjectArgumentInitialization(*this, Object->getType(), 5105 Object->Classify(Context), 5106 Conversion, ActingContext); 5107 if (ObjectInit.isBad()) { 5108 Candidate.Viable = false; 5109 Candidate.FailureKind = ovl_fail_bad_conversion; 5110 Candidate.Conversions[0] = ObjectInit; 5111 return; 5112 } 5113 5114 // The first conversion is actually a user-defined conversion whose 5115 // first conversion is ObjectInit's standard conversion (which is 5116 // effectively a reference binding). Record it as such. 5117 Candidate.Conversions[0].setUserDefined(); 5118 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard; 5119 Candidate.Conversions[0].UserDefined.EllipsisConversion = false; 5120 Candidate.Conversions[0].UserDefined.HadMultipleCandidates = false; 5121 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion; 5122 Candidate.Conversions[0].UserDefined.FoundConversionFunction = FoundDecl; 5123 Candidate.Conversions[0].UserDefined.After 5124 = Candidate.Conversions[0].UserDefined.Before; 5125 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion(); 5126 5127 // Find the 5128 unsigned NumArgsInProto = Proto->getNumArgs(); 5129 5130 // (C++ 13.3.2p2): A candidate function having fewer than m 5131 // parameters is viable only if it has an ellipsis in its parameter 5132 // list (8.3.5). 5133 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 5134 Candidate.Viable = false; 5135 Candidate.FailureKind = ovl_fail_too_many_arguments; 5136 return; 5137 } 5138 5139 // Function types don't have any default arguments, so just check if 5140 // we have enough arguments. 5141 if (NumArgs < NumArgsInProto) { 5142 // Not enough arguments. 5143 Candidate.Viable = false; 5144 Candidate.FailureKind = ovl_fail_too_few_arguments; 5145 return; 5146 } 5147 5148 // Determine the implicit conversion sequences for each of the 5149 // arguments. 5150 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5151 if (ArgIdx < NumArgsInProto) { 5152 // (C++ 13.3.2p3): for F to be a viable function, there shall 5153 // exist for each argument an implicit conversion sequence 5154 // (13.3.3.1) that converts that argument to the corresponding 5155 // parameter of F. 5156 QualType ParamType = Proto->getArgType(ArgIdx); 5157 Candidate.Conversions[ArgIdx + 1] 5158 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 5159 /*SuppressUserConversions=*/false, 5160 /*InOverloadResolution=*/false, 5161 /*AllowObjCWritebackConversion=*/ 5162 getLangOptions().ObjCAutoRefCount); 5163 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 5164 Candidate.Viable = false; 5165 Candidate.FailureKind = ovl_fail_bad_conversion; 5166 break; 5167 } 5168 } else { 5169 // (C++ 13.3.2p2): For the purposes of overload resolution, any 5170 // argument for which there is no corresponding parameter is 5171 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 5172 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 5173 } 5174 } 5175} 5176 5177/// \brief Add overload candidates for overloaded operators that are 5178/// member functions. 5179/// 5180/// Add the overloaded operator candidates that are member functions 5181/// for the operator Op that was used in an operator expression such 5182/// as "x Op y". , Args/NumArgs provides the operator arguments, and 5183/// CandidateSet will store the added overload candidates. (C++ 5184/// [over.match.oper]). 5185void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op, 5186 SourceLocation OpLoc, 5187 Expr **Args, unsigned NumArgs, 5188 OverloadCandidateSet& CandidateSet, 5189 SourceRange OpRange) { 5190 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 5191 5192 // C++ [over.match.oper]p3: 5193 // For a unary operator @ with an operand of a type whose 5194 // cv-unqualified version is T1, and for a binary operator @ with 5195 // a left operand of a type whose cv-unqualified version is T1 and 5196 // a right operand of a type whose cv-unqualified version is T2, 5197 // three sets of candidate functions, designated member 5198 // candidates, non-member candidates and built-in candidates, are 5199 // constructed as follows: 5200 QualType T1 = Args[0]->getType(); 5201 5202 // -- If T1 is a class type, the set of member candidates is the 5203 // result of the qualified lookup of T1::operator@ 5204 // (13.3.1.1.1); otherwise, the set of member candidates is 5205 // empty. 5206 if (const RecordType *T1Rec = T1->getAs<RecordType>()) { 5207 // Complete the type if it can be completed. Otherwise, we're done. 5208 if (RequireCompleteType(OpLoc, T1, PDiag())) 5209 return; 5210 5211 LookupResult Operators(*this, OpName, OpLoc, LookupOrdinaryName); 5212 LookupQualifiedName(Operators, T1Rec->getDecl()); 5213 Operators.suppressDiagnostics(); 5214 5215 for (LookupResult::iterator Oper = Operators.begin(), 5216 OperEnd = Operators.end(); 5217 Oper != OperEnd; 5218 ++Oper) 5219 AddMethodCandidate(Oper.getPair(), Args[0]->getType(), 5220 Args[0]->Classify(Context), Args + 1, NumArgs - 1, 5221 CandidateSet, 5222 /* SuppressUserConversions = */ false); 5223 } 5224} 5225 5226/// AddBuiltinCandidate - Add a candidate for a built-in 5227/// operator. ResultTy and ParamTys are the result and parameter types 5228/// of the built-in candidate, respectively. Args and NumArgs are the 5229/// arguments being passed to the candidate. IsAssignmentOperator 5230/// should be true when this built-in candidate is an assignment 5231/// operator. NumContextualBoolArguments is the number of arguments 5232/// (at the beginning of the argument list) that will be contextually 5233/// converted to bool. 5234void Sema::AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys, 5235 Expr **Args, unsigned NumArgs, 5236 OverloadCandidateSet& CandidateSet, 5237 bool IsAssignmentOperator, 5238 unsigned NumContextualBoolArguments) { 5239 // Overload resolution is always an unevaluated context. 5240 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 5241 5242 // Add this candidate 5243 CandidateSet.push_back(OverloadCandidate()); 5244 OverloadCandidate& Candidate = CandidateSet.back(); 5245 Candidate.FoundDecl = DeclAccessPair::make(0, AS_none); 5246 Candidate.Function = 0; 5247 Candidate.IsSurrogate = false; 5248 Candidate.IgnoreObjectArgument = false; 5249 Candidate.BuiltinTypes.ResultTy = ResultTy; 5250 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 5251 Candidate.BuiltinTypes.ParamTypes[ArgIdx] = ParamTys[ArgIdx]; 5252 5253 // Determine the implicit conversion sequences for each of the 5254 // arguments. 5255 Candidate.Viable = true; 5256 Candidate.Conversions.resize(NumArgs); 5257 Candidate.ExplicitCallArguments = NumArgs; 5258 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5259 // C++ [over.match.oper]p4: 5260 // For the built-in assignment operators, conversions of the 5261 // left operand are restricted as follows: 5262 // -- no temporaries are introduced to hold the left operand, and 5263 // -- no user-defined conversions are applied to the left 5264 // operand to achieve a type match with the left-most 5265 // parameter of a built-in candidate. 5266 // 5267 // We block these conversions by turning off user-defined 5268 // conversions, since that is the only way that initialization of 5269 // a reference to a non-class type can occur from something that 5270 // is not of the same type. 5271 if (ArgIdx < NumContextualBoolArguments) { 5272 assert(ParamTys[ArgIdx] == Context.BoolTy && 5273 "Contextual conversion to bool requires bool type"); 5274 Candidate.Conversions[ArgIdx] 5275 = TryContextuallyConvertToBool(*this, Args[ArgIdx]); 5276 } else { 5277 Candidate.Conversions[ArgIdx] 5278 = TryCopyInitialization(*this, Args[ArgIdx], ParamTys[ArgIdx], 5279 ArgIdx == 0 && IsAssignmentOperator, 5280 /*InOverloadResolution=*/false, 5281 /*AllowObjCWritebackConversion=*/ 5282 getLangOptions().ObjCAutoRefCount); 5283 } 5284 if (Candidate.Conversions[ArgIdx].isBad()) { 5285 Candidate.Viable = false; 5286 Candidate.FailureKind = ovl_fail_bad_conversion; 5287 break; 5288 } 5289 } 5290} 5291 5292/// BuiltinCandidateTypeSet - A set of types that will be used for the 5293/// candidate operator functions for built-in operators (C++ 5294/// [over.built]). The types are separated into pointer types and 5295/// enumeration types. 5296class BuiltinCandidateTypeSet { 5297 /// TypeSet - A set of types. 5298 typedef llvm::SmallPtrSet<QualType, 8> TypeSet; 5299 5300 /// PointerTypes - The set of pointer types that will be used in the 5301 /// built-in candidates. 5302 TypeSet PointerTypes; 5303 5304 /// MemberPointerTypes - The set of member pointer types that will be 5305 /// used in the built-in candidates. 5306 TypeSet MemberPointerTypes; 5307 5308 /// EnumerationTypes - The set of enumeration types that will be 5309 /// used in the built-in candidates. 5310 TypeSet EnumerationTypes; 5311 5312 /// \brief The set of vector types that will be used in the built-in 5313 /// candidates. 5314 TypeSet VectorTypes; 5315 5316 /// \brief A flag indicating non-record types are viable candidates 5317 bool HasNonRecordTypes; 5318 5319 /// \brief A flag indicating whether either arithmetic or enumeration types 5320 /// were present in the candidate set. 5321 bool HasArithmeticOrEnumeralTypes; 5322 5323 /// \brief A flag indicating whether the nullptr type was present in the 5324 /// candidate set. 5325 bool HasNullPtrType; 5326 5327 /// Sema - The semantic analysis instance where we are building the 5328 /// candidate type set. 5329 Sema &SemaRef; 5330 5331 /// Context - The AST context in which we will build the type sets. 5332 ASTContext &Context; 5333 5334 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 5335 const Qualifiers &VisibleQuals); 5336 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty); 5337 5338public: 5339 /// iterator - Iterates through the types that are part of the set. 5340 typedef TypeSet::iterator iterator; 5341 5342 BuiltinCandidateTypeSet(Sema &SemaRef) 5343 : HasNonRecordTypes(false), 5344 HasArithmeticOrEnumeralTypes(false), 5345 HasNullPtrType(false), 5346 SemaRef(SemaRef), 5347 Context(SemaRef.Context) { } 5348 5349 void AddTypesConvertedFrom(QualType Ty, 5350 SourceLocation Loc, 5351 bool AllowUserConversions, 5352 bool AllowExplicitConversions, 5353 const Qualifiers &VisibleTypeConversionsQuals); 5354 5355 /// pointer_begin - First pointer type found; 5356 iterator pointer_begin() { return PointerTypes.begin(); } 5357 5358 /// pointer_end - Past the last pointer type found; 5359 iterator pointer_end() { return PointerTypes.end(); } 5360 5361 /// member_pointer_begin - First member pointer type found; 5362 iterator member_pointer_begin() { return MemberPointerTypes.begin(); } 5363 5364 /// member_pointer_end - Past the last member pointer type found; 5365 iterator member_pointer_end() { return MemberPointerTypes.end(); } 5366 5367 /// enumeration_begin - First enumeration type found; 5368 iterator enumeration_begin() { return EnumerationTypes.begin(); } 5369 5370 /// enumeration_end - Past the last enumeration type found; 5371 iterator enumeration_end() { return EnumerationTypes.end(); } 5372 5373 iterator vector_begin() { return VectorTypes.begin(); } 5374 iterator vector_end() { return VectorTypes.end(); } 5375 5376 bool hasNonRecordTypes() { return HasNonRecordTypes; } 5377 bool hasArithmeticOrEnumeralTypes() { return HasArithmeticOrEnumeralTypes; } 5378 bool hasNullPtrType() const { return HasNullPtrType; } 5379}; 5380 5381/// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to 5382/// the set of pointer types along with any more-qualified variants of 5383/// that type. For example, if @p Ty is "int const *", this routine 5384/// will add "int const *", "int const volatile *", "int const 5385/// restrict *", and "int const volatile restrict *" to the set of 5386/// pointer types. Returns true if the add of @p Ty itself succeeded, 5387/// false otherwise. 5388/// 5389/// FIXME: what to do about extended qualifiers? 5390bool 5391BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 5392 const Qualifiers &VisibleQuals) { 5393 5394 // Insert this type. 5395 if (!PointerTypes.insert(Ty)) 5396 return false; 5397 5398 QualType PointeeTy; 5399 const PointerType *PointerTy = Ty->getAs<PointerType>(); 5400 bool buildObjCPtr = false; 5401 if (!PointerTy) { 5402 if (const ObjCObjectPointerType *PTy = Ty->getAs<ObjCObjectPointerType>()) { 5403 PointeeTy = PTy->getPointeeType(); 5404 buildObjCPtr = true; 5405 } 5406 else 5407 llvm_unreachable("type was not a pointer type!"); 5408 } 5409 else 5410 PointeeTy = PointerTy->getPointeeType(); 5411 5412 // Don't add qualified variants of arrays. For one, they're not allowed 5413 // (the qualifier would sink to the element type), and for another, the 5414 // only overload situation where it matters is subscript or pointer +- int, 5415 // and those shouldn't have qualifier variants anyway. 5416 if (PointeeTy->isArrayType()) 5417 return true; 5418 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 5419 if (const ConstantArrayType *Array =Context.getAsConstantArrayType(PointeeTy)) 5420 BaseCVR = Array->getElementType().getCVRQualifiers(); 5421 bool hasVolatile = VisibleQuals.hasVolatile(); 5422 bool hasRestrict = VisibleQuals.hasRestrict(); 5423 5424 // Iterate through all strict supersets of BaseCVR. 5425 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 5426 if ((CVR | BaseCVR) != CVR) continue; 5427 // Skip over Volatile/Restrict if no Volatile/Restrict found anywhere 5428 // in the types. 5429 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue; 5430 if ((CVR & Qualifiers::Restrict) && !hasRestrict) continue; 5431 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 5432 if (!buildObjCPtr) 5433 PointerTypes.insert(Context.getPointerType(QPointeeTy)); 5434 else 5435 PointerTypes.insert(Context.getObjCObjectPointerType(QPointeeTy)); 5436 } 5437 5438 return true; 5439} 5440 5441/// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty 5442/// to the set of pointer types along with any more-qualified variants of 5443/// that type. For example, if @p Ty is "int const *", this routine 5444/// will add "int const *", "int const volatile *", "int const 5445/// restrict *", and "int const volatile restrict *" to the set of 5446/// pointer types. Returns true if the add of @p Ty itself succeeded, 5447/// false otherwise. 5448/// 5449/// FIXME: what to do about extended qualifiers? 5450bool 5451BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants( 5452 QualType Ty) { 5453 // Insert this type. 5454 if (!MemberPointerTypes.insert(Ty)) 5455 return false; 5456 5457 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>(); 5458 assert(PointerTy && "type was not a member pointer type!"); 5459 5460 QualType PointeeTy = PointerTy->getPointeeType(); 5461 // Don't add qualified variants of arrays. For one, they're not allowed 5462 // (the qualifier would sink to the element type), and for another, the 5463 // only overload situation where it matters is subscript or pointer +- int, 5464 // and those shouldn't have qualifier variants anyway. 5465 if (PointeeTy->isArrayType()) 5466 return true; 5467 const Type *ClassTy = PointerTy->getClass(); 5468 5469 // Iterate through all strict supersets of the pointee type's CVR 5470 // qualifiers. 5471 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 5472 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 5473 if ((CVR | BaseCVR) != CVR) continue; 5474 5475 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 5476 MemberPointerTypes.insert( 5477 Context.getMemberPointerType(QPointeeTy, ClassTy)); 5478 } 5479 5480 return true; 5481} 5482 5483/// AddTypesConvertedFrom - Add each of the types to which the type @p 5484/// Ty can be implicit converted to the given set of @p Types. We're 5485/// primarily interested in pointer types and enumeration types. We also 5486/// take member pointer types, for the conditional operator. 5487/// AllowUserConversions is true if we should look at the conversion 5488/// functions of a class type, and AllowExplicitConversions if we 5489/// should also include the explicit conversion functions of a class 5490/// type. 5491void 5492BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty, 5493 SourceLocation Loc, 5494 bool AllowUserConversions, 5495 bool AllowExplicitConversions, 5496 const Qualifiers &VisibleQuals) { 5497 // Only deal with canonical types. 5498 Ty = Context.getCanonicalType(Ty); 5499 5500 // Look through reference types; they aren't part of the type of an 5501 // expression for the purposes of conversions. 5502 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>()) 5503 Ty = RefTy->getPointeeType(); 5504 5505 // If we're dealing with an array type, decay to the pointer. 5506 if (Ty->isArrayType()) 5507 Ty = SemaRef.Context.getArrayDecayedType(Ty); 5508 5509 // Otherwise, we don't care about qualifiers on the type. 5510 Ty = Ty.getLocalUnqualifiedType(); 5511 5512 // Flag if we ever add a non-record type. 5513 const RecordType *TyRec = Ty->getAs<RecordType>(); 5514 HasNonRecordTypes = HasNonRecordTypes || !TyRec; 5515 5516 // Flag if we encounter an arithmetic type. 5517 HasArithmeticOrEnumeralTypes = 5518 HasArithmeticOrEnumeralTypes || Ty->isArithmeticType(); 5519 5520 if (Ty->isObjCIdType() || Ty->isObjCClassType()) 5521 PointerTypes.insert(Ty); 5522 else if (Ty->getAs<PointerType>() || Ty->getAs<ObjCObjectPointerType>()) { 5523 // Insert our type, and its more-qualified variants, into the set 5524 // of types. 5525 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals)) 5526 return; 5527 } else if (Ty->isMemberPointerType()) { 5528 // Member pointers are far easier, since the pointee can't be converted. 5529 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty)) 5530 return; 5531 } else if (Ty->isEnumeralType()) { 5532 HasArithmeticOrEnumeralTypes = true; 5533 EnumerationTypes.insert(Ty); 5534 } else if (Ty->isVectorType()) { 5535 // We treat vector types as arithmetic types in many contexts as an 5536 // extension. 5537 HasArithmeticOrEnumeralTypes = true; 5538 VectorTypes.insert(Ty); 5539 } else if (Ty->isNullPtrType()) { 5540 HasNullPtrType = true; 5541 } else if (AllowUserConversions && TyRec) { 5542 // No conversion functions in incomplete types. 5543 if (SemaRef.RequireCompleteType(Loc, Ty, 0)) 5544 return; 5545 5546 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 5547 const UnresolvedSetImpl *Conversions 5548 = ClassDecl->getVisibleConversionFunctions(); 5549 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 5550 E = Conversions->end(); I != E; ++I) { 5551 NamedDecl *D = I.getDecl(); 5552 if (isa<UsingShadowDecl>(D)) 5553 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 5554 5555 // Skip conversion function templates; they don't tell us anything 5556 // about which builtin types we can convert to. 5557 if (isa<FunctionTemplateDecl>(D)) 5558 continue; 5559 5560 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 5561 if (AllowExplicitConversions || !Conv->isExplicit()) { 5562 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false, 5563 VisibleQuals); 5564 } 5565 } 5566 } 5567} 5568 5569/// \brief Helper function for AddBuiltinOperatorCandidates() that adds 5570/// the volatile- and non-volatile-qualified assignment operators for the 5571/// given type to the candidate set. 5572static void AddBuiltinAssignmentOperatorCandidates(Sema &S, 5573 QualType T, 5574 Expr **Args, 5575 unsigned NumArgs, 5576 OverloadCandidateSet &CandidateSet) { 5577 QualType ParamTypes[2]; 5578 5579 // T& operator=(T&, T) 5580 ParamTypes[0] = S.Context.getLValueReferenceType(T); 5581 ParamTypes[1] = T; 5582 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5583 /*IsAssignmentOperator=*/true); 5584 5585 if (!S.Context.getCanonicalType(T).isVolatileQualified()) { 5586 // volatile T& operator=(volatile T&, T) 5587 ParamTypes[0] 5588 = S.Context.getLValueReferenceType(S.Context.getVolatileType(T)); 5589 ParamTypes[1] = T; 5590 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5591 /*IsAssignmentOperator=*/true); 5592 } 5593} 5594 5595/// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers, 5596/// if any, found in visible type conversion functions found in ArgExpr's type. 5597static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) { 5598 Qualifiers VRQuals; 5599 const RecordType *TyRec; 5600 if (const MemberPointerType *RHSMPType = 5601 ArgExpr->getType()->getAs<MemberPointerType>()) 5602 TyRec = RHSMPType->getClass()->getAs<RecordType>(); 5603 else 5604 TyRec = ArgExpr->getType()->getAs<RecordType>(); 5605 if (!TyRec) { 5606 // Just to be safe, assume the worst case. 5607 VRQuals.addVolatile(); 5608 VRQuals.addRestrict(); 5609 return VRQuals; 5610 } 5611 5612 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 5613 if (!ClassDecl->hasDefinition()) 5614 return VRQuals; 5615 5616 const UnresolvedSetImpl *Conversions = 5617 ClassDecl->getVisibleConversionFunctions(); 5618 5619 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 5620 E = Conversions->end(); I != E; ++I) { 5621 NamedDecl *D = I.getDecl(); 5622 if (isa<UsingShadowDecl>(D)) 5623 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 5624 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) { 5625 QualType CanTy = Context.getCanonicalType(Conv->getConversionType()); 5626 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>()) 5627 CanTy = ResTypeRef->getPointeeType(); 5628 // Need to go down the pointer/mempointer chain and add qualifiers 5629 // as see them. 5630 bool done = false; 5631 while (!done) { 5632 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>()) 5633 CanTy = ResTypePtr->getPointeeType(); 5634 else if (const MemberPointerType *ResTypeMPtr = 5635 CanTy->getAs<MemberPointerType>()) 5636 CanTy = ResTypeMPtr->getPointeeType(); 5637 else 5638 done = true; 5639 if (CanTy.isVolatileQualified()) 5640 VRQuals.addVolatile(); 5641 if (CanTy.isRestrictQualified()) 5642 VRQuals.addRestrict(); 5643 if (VRQuals.hasRestrict() && VRQuals.hasVolatile()) 5644 return VRQuals; 5645 } 5646 } 5647 } 5648 return VRQuals; 5649} 5650 5651namespace { 5652 5653/// \brief Helper class to manage the addition of builtin operator overload 5654/// candidates. It provides shared state and utility methods used throughout 5655/// the process, as well as a helper method to add each group of builtin 5656/// operator overloads from the standard to a candidate set. 5657class BuiltinOperatorOverloadBuilder { 5658 // Common instance state available to all overload candidate addition methods. 5659 Sema &S; 5660 Expr **Args; 5661 unsigned NumArgs; 5662 Qualifiers VisibleTypeConversionsQuals; 5663 bool HasArithmeticOrEnumeralCandidateType; 5664 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes; 5665 OverloadCandidateSet &CandidateSet; 5666 5667 // Define some constants used to index and iterate over the arithemetic types 5668 // provided via the getArithmeticType() method below. 5669 // The "promoted arithmetic types" are the arithmetic 5670 // types are that preserved by promotion (C++ [over.built]p2). 5671 static const unsigned FirstIntegralType = 3; 5672 static const unsigned LastIntegralType = 18; 5673 static const unsigned FirstPromotedIntegralType = 3, 5674 LastPromotedIntegralType = 9; 5675 static const unsigned FirstPromotedArithmeticType = 0, 5676 LastPromotedArithmeticType = 9; 5677 static const unsigned NumArithmeticTypes = 18; 5678 5679 /// \brief Get the canonical type for a given arithmetic type index. 5680 CanQualType getArithmeticType(unsigned index) { 5681 assert(index < NumArithmeticTypes); 5682 static CanQualType ASTContext::* const 5683 ArithmeticTypes[NumArithmeticTypes] = { 5684 // Start of promoted types. 5685 &ASTContext::FloatTy, 5686 &ASTContext::DoubleTy, 5687 &ASTContext::LongDoubleTy, 5688 5689 // Start of integral types. 5690 &ASTContext::IntTy, 5691 &ASTContext::LongTy, 5692 &ASTContext::LongLongTy, 5693 &ASTContext::UnsignedIntTy, 5694 &ASTContext::UnsignedLongTy, 5695 &ASTContext::UnsignedLongLongTy, 5696 // End of promoted types. 5697 5698 &ASTContext::BoolTy, 5699 &ASTContext::CharTy, 5700 &ASTContext::WCharTy, 5701 &ASTContext::Char16Ty, 5702 &ASTContext::Char32Ty, 5703 &ASTContext::SignedCharTy, 5704 &ASTContext::ShortTy, 5705 &ASTContext::UnsignedCharTy, 5706 &ASTContext::UnsignedShortTy, 5707 // End of integral types. 5708 // FIXME: What about complex? 5709 }; 5710 return S.Context.*ArithmeticTypes[index]; 5711 } 5712 5713 /// \brief Gets the canonical type resulting from the usual arithemetic 5714 /// converions for the given arithmetic types. 5715 CanQualType getUsualArithmeticConversions(unsigned L, unsigned R) { 5716 // Accelerator table for performing the usual arithmetic conversions. 5717 // The rules are basically: 5718 // - if either is floating-point, use the wider floating-point 5719 // - if same signedness, use the higher rank 5720 // - if same size, use unsigned of the higher rank 5721 // - use the larger type 5722 // These rules, together with the axiom that higher ranks are 5723 // never smaller, are sufficient to precompute all of these results 5724 // *except* when dealing with signed types of higher rank. 5725 // (we could precompute SLL x UI for all known platforms, but it's 5726 // better not to make any assumptions). 5727 enum PromotedType { 5728 Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL, Dep=-1 5729 }; 5730 static PromotedType ConversionsTable[LastPromotedArithmeticType] 5731 [LastPromotedArithmeticType] = { 5732 /* Flt*/ { Flt, Dbl, LDbl, Flt, Flt, Flt, Flt, Flt, Flt }, 5733 /* Dbl*/ { Dbl, Dbl, LDbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl }, 5734 /*LDbl*/ { LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl }, 5735 /* SI*/ { Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL }, 5736 /* SL*/ { Flt, Dbl, LDbl, SL, SL, SLL, Dep, UL, ULL }, 5737 /* SLL*/ { Flt, Dbl, LDbl, SLL, SLL, SLL, Dep, Dep, ULL }, 5738 /* UI*/ { Flt, Dbl, LDbl, UI, Dep, Dep, UI, UL, ULL }, 5739 /* UL*/ { Flt, Dbl, LDbl, UL, UL, Dep, UL, UL, ULL }, 5740 /* ULL*/ { Flt, Dbl, LDbl, ULL, ULL, ULL, ULL, ULL, ULL }, 5741 }; 5742 5743 assert(L < LastPromotedArithmeticType); 5744 assert(R < LastPromotedArithmeticType); 5745 int Idx = ConversionsTable[L][R]; 5746 5747 // Fast path: the table gives us a concrete answer. 5748 if (Idx != Dep) return getArithmeticType(Idx); 5749 5750 // Slow path: we need to compare widths. 5751 // An invariant is that the signed type has higher rank. 5752 CanQualType LT = getArithmeticType(L), 5753 RT = getArithmeticType(R); 5754 unsigned LW = S.Context.getIntWidth(LT), 5755 RW = S.Context.getIntWidth(RT); 5756 5757 // If they're different widths, use the signed type. 5758 if (LW > RW) return LT; 5759 else if (LW < RW) return RT; 5760 5761 // Otherwise, use the unsigned type of the signed type's rank. 5762 if (L == SL || R == SL) return S.Context.UnsignedLongTy; 5763 assert(L == SLL || R == SLL); 5764 return S.Context.UnsignedLongLongTy; 5765 } 5766 5767 /// \brief Helper method to factor out the common pattern of adding overloads 5768 /// for '++' and '--' builtin operators. 5769 void addPlusPlusMinusMinusStyleOverloads(QualType CandidateTy, 5770 bool HasVolatile) { 5771 QualType ParamTypes[2] = { 5772 S.Context.getLValueReferenceType(CandidateTy), 5773 S.Context.IntTy 5774 }; 5775 5776 // Non-volatile version. 5777 if (NumArgs == 1) 5778 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5779 else 5780 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5781 5782 // Use a heuristic to reduce number of builtin candidates in the set: 5783 // add volatile version only if there are conversions to a volatile type. 5784 if (HasVolatile) { 5785 ParamTypes[0] = 5786 S.Context.getLValueReferenceType( 5787 S.Context.getVolatileType(CandidateTy)); 5788 if (NumArgs == 1) 5789 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5790 else 5791 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5792 } 5793 } 5794 5795public: 5796 BuiltinOperatorOverloadBuilder( 5797 Sema &S, Expr **Args, unsigned NumArgs, 5798 Qualifiers VisibleTypeConversionsQuals, 5799 bool HasArithmeticOrEnumeralCandidateType, 5800 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes, 5801 OverloadCandidateSet &CandidateSet) 5802 : S(S), Args(Args), NumArgs(NumArgs), 5803 VisibleTypeConversionsQuals(VisibleTypeConversionsQuals), 5804 HasArithmeticOrEnumeralCandidateType( 5805 HasArithmeticOrEnumeralCandidateType), 5806 CandidateTypes(CandidateTypes), 5807 CandidateSet(CandidateSet) { 5808 // Validate some of our static helper constants in debug builds. 5809 assert(getArithmeticType(FirstPromotedIntegralType) == S.Context.IntTy && 5810 "Invalid first promoted integral type"); 5811 assert(getArithmeticType(LastPromotedIntegralType - 1) 5812 == S.Context.UnsignedLongLongTy && 5813 "Invalid last promoted integral type"); 5814 assert(getArithmeticType(FirstPromotedArithmeticType) 5815 == S.Context.FloatTy && 5816 "Invalid first promoted arithmetic type"); 5817 assert(getArithmeticType(LastPromotedArithmeticType - 1) 5818 == S.Context.UnsignedLongLongTy && 5819 "Invalid last promoted arithmetic type"); 5820 } 5821 5822 // C++ [over.built]p3: 5823 // 5824 // For every pair (T, VQ), where T is an arithmetic type, and VQ 5825 // is either volatile or empty, there exist candidate operator 5826 // functions of the form 5827 // 5828 // VQ T& operator++(VQ T&); 5829 // T operator++(VQ T&, int); 5830 // 5831 // C++ [over.built]p4: 5832 // 5833 // For every pair (T, VQ), where T is an arithmetic type other 5834 // than bool, and VQ is either volatile or empty, there exist 5835 // candidate operator functions of the form 5836 // 5837 // VQ T& operator--(VQ T&); 5838 // T operator--(VQ T&, int); 5839 void addPlusPlusMinusMinusArithmeticOverloads(OverloadedOperatorKind Op) { 5840 if (!HasArithmeticOrEnumeralCandidateType) 5841 return; 5842 5843 for (unsigned Arith = (Op == OO_PlusPlus? 0 : 1); 5844 Arith < NumArithmeticTypes; ++Arith) { 5845 addPlusPlusMinusMinusStyleOverloads( 5846 getArithmeticType(Arith), 5847 VisibleTypeConversionsQuals.hasVolatile()); 5848 } 5849 } 5850 5851 // C++ [over.built]p5: 5852 // 5853 // For every pair (T, VQ), where T is a cv-qualified or 5854 // cv-unqualified object type, and VQ is either volatile or 5855 // empty, there exist candidate operator functions of the form 5856 // 5857 // T*VQ& operator++(T*VQ&); 5858 // T*VQ& operator--(T*VQ&); 5859 // T* operator++(T*VQ&, int); 5860 // T* operator--(T*VQ&, int); 5861 void addPlusPlusMinusMinusPointerOverloads() { 5862 for (BuiltinCandidateTypeSet::iterator 5863 Ptr = CandidateTypes[0].pointer_begin(), 5864 PtrEnd = CandidateTypes[0].pointer_end(); 5865 Ptr != PtrEnd; ++Ptr) { 5866 // Skip pointer types that aren't pointers to object types. 5867 if (!(*Ptr)->getPointeeType()->isObjectType()) 5868 continue; 5869 5870 addPlusPlusMinusMinusStyleOverloads(*Ptr, 5871 (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5872 VisibleTypeConversionsQuals.hasVolatile())); 5873 } 5874 } 5875 5876 // C++ [over.built]p6: 5877 // For every cv-qualified or cv-unqualified object type T, there 5878 // exist candidate operator functions of the form 5879 // 5880 // T& operator*(T*); 5881 // 5882 // C++ [over.built]p7: 5883 // For every function type T that does not have cv-qualifiers or a 5884 // ref-qualifier, there exist candidate operator functions of the form 5885 // T& operator*(T*); 5886 void addUnaryStarPointerOverloads() { 5887 for (BuiltinCandidateTypeSet::iterator 5888 Ptr = CandidateTypes[0].pointer_begin(), 5889 PtrEnd = CandidateTypes[0].pointer_end(); 5890 Ptr != PtrEnd; ++Ptr) { 5891 QualType ParamTy = *Ptr; 5892 QualType PointeeTy = ParamTy->getPointeeType(); 5893 if (!PointeeTy->isObjectType() && !PointeeTy->isFunctionType()) 5894 continue; 5895 5896 if (const FunctionProtoType *Proto =PointeeTy->getAs<FunctionProtoType>()) 5897 if (Proto->getTypeQuals() || Proto->getRefQualifier()) 5898 continue; 5899 5900 S.AddBuiltinCandidate(S.Context.getLValueReferenceType(PointeeTy), 5901 &ParamTy, Args, 1, CandidateSet); 5902 } 5903 } 5904 5905 // C++ [over.built]p9: 5906 // For every promoted arithmetic type T, there exist candidate 5907 // operator functions of the form 5908 // 5909 // T operator+(T); 5910 // T operator-(T); 5911 void addUnaryPlusOrMinusArithmeticOverloads() { 5912 if (!HasArithmeticOrEnumeralCandidateType) 5913 return; 5914 5915 for (unsigned Arith = FirstPromotedArithmeticType; 5916 Arith < LastPromotedArithmeticType; ++Arith) { 5917 QualType ArithTy = getArithmeticType(Arith); 5918 S.AddBuiltinCandidate(ArithTy, &ArithTy, Args, 1, CandidateSet); 5919 } 5920 5921 // Extension: We also add these operators for vector types. 5922 for (BuiltinCandidateTypeSet::iterator 5923 Vec = CandidateTypes[0].vector_begin(), 5924 VecEnd = CandidateTypes[0].vector_end(); 5925 Vec != VecEnd; ++Vec) { 5926 QualType VecTy = *Vec; 5927 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5928 } 5929 } 5930 5931 // C++ [over.built]p8: 5932 // For every type T, there exist candidate operator functions of 5933 // the form 5934 // 5935 // T* operator+(T*); 5936 void addUnaryPlusPointerOverloads() { 5937 for (BuiltinCandidateTypeSet::iterator 5938 Ptr = CandidateTypes[0].pointer_begin(), 5939 PtrEnd = CandidateTypes[0].pointer_end(); 5940 Ptr != PtrEnd; ++Ptr) { 5941 QualType ParamTy = *Ptr; 5942 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet); 5943 } 5944 } 5945 5946 // C++ [over.built]p10: 5947 // For every promoted integral type T, there exist candidate 5948 // operator functions of the form 5949 // 5950 // T operator~(T); 5951 void addUnaryTildePromotedIntegralOverloads() { 5952 if (!HasArithmeticOrEnumeralCandidateType) 5953 return; 5954 5955 for (unsigned Int = FirstPromotedIntegralType; 5956 Int < LastPromotedIntegralType; ++Int) { 5957 QualType IntTy = getArithmeticType(Int); 5958 S.AddBuiltinCandidate(IntTy, &IntTy, Args, 1, CandidateSet); 5959 } 5960 5961 // Extension: We also add this operator for vector types. 5962 for (BuiltinCandidateTypeSet::iterator 5963 Vec = CandidateTypes[0].vector_begin(), 5964 VecEnd = CandidateTypes[0].vector_end(); 5965 Vec != VecEnd; ++Vec) { 5966 QualType VecTy = *Vec; 5967 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5968 } 5969 } 5970 5971 // C++ [over.match.oper]p16: 5972 // For every pointer to member type T, there exist candidate operator 5973 // functions of the form 5974 // 5975 // bool operator==(T,T); 5976 // bool operator!=(T,T); 5977 void addEqualEqualOrNotEqualMemberPointerOverloads() { 5978 /// Set of (canonical) types that we've already handled. 5979 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5980 5981 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5982 for (BuiltinCandidateTypeSet::iterator 5983 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5984 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5985 MemPtr != MemPtrEnd; 5986 ++MemPtr) { 5987 // Don't add the same builtin candidate twice. 5988 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5989 continue; 5990 5991 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 5992 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5993 CandidateSet); 5994 } 5995 } 5996 } 5997 5998 // C++ [over.built]p15: 5999 // 6000 // For every T, where T is an enumeration type, a pointer type, or 6001 // std::nullptr_t, there exist candidate operator functions of the form 6002 // 6003 // bool operator<(T, T); 6004 // bool operator>(T, T); 6005 // bool operator<=(T, T); 6006 // bool operator>=(T, T); 6007 // bool operator==(T, T); 6008 // bool operator!=(T, T); 6009 void addRelationalPointerOrEnumeralOverloads() { 6010 // C++ [over.built]p1: 6011 // If there is a user-written candidate with the same name and parameter 6012 // types as a built-in candidate operator function, the built-in operator 6013 // function is hidden and is not included in the set of candidate 6014 // functions. 6015 // 6016 // The text is actually in a note, but if we don't implement it then we end 6017 // up with ambiguities when the user provides an overloaded operator for 6018 // an enumeration type. Note that only enumeration types have this problem, 6019 // so we track which enumeration types we've seen operators for. Also, the 6020 // only other overloaded operator with enumeration argumenst, operator=, 6021 // cannot be overloaded for enumeration types, so this is the only place 6022 // where we must suppress candidates like this. 6023 llvm::DenseSet<std::pair<CanQualType, CanQualType> > 6024 UserDefinedBinaryOperators; 6025 6026 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6027 if (CandidateTypes[ArgIdx].enumeration_begin() != 6028 CandidateTypes[ArgIdx].enumeration_end()) { 6029 for (OverloadCandidateSet::iterator C = CandidateSet.begin(), 6030 CEnd = CandidateSet.end(); 6031 C != CEnd; ++C) { 6032 if (!C->Viable || !C->Function || C->Function->getNumParams() != 2) 6033 continue; 6034 6035 QualType FirstParamType = 6036 C->Function->getParamDecl(0)->getType().getUnqualifiedType(); 6037 QualType SecondParamType = 6038 C->Function->getParamDecl(1)->getType().getUnqualifiedType(); 6039 6040 // Skip if either parameter isn't of enumeral type. 6041 if (!FirstParamType->isEnumeralType() || 6042 !SecondParamType->isEnumeralType()) 6043 continue; 6044 6045 // Add this operator to the set of known user-defined operators. 6046 UserDefinedBinaryOperators.insert( 6047 std::make_pair(S.Context.getCanonicalType(FirstParamType), 6048 S.Context.getCanonicalType(SecondParamType))); 6049 } 6050 } 6051 } 6052 6053 /// Set of (canonical) types that we've already handled. 6054 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6055 6056 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6057 for (BuiltinCandidateTypeSet::iterator 6058 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 6059 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 6060 Ptr != PtrEnd; ++Ptr) { 6061 // Don't add the same builtin candidate twice. 6062 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 6063 continue; 6064 6065 QualType ParamTypes[2] = { *Ptr, *Ptr }; 6066 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 6067 CandidateSet); 6068 } 6069 for (BuiltinCandidateTypeSet::iterator 6070 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 6071 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 6072 Enum != EnumEnd; ++Enum) { 6073 CanQualType CanonType = S.Context.getCanonicalType(*Enum); 6074 6075 // Don't add the same builtin candidate twice, or if a user defined 6076 // candidate exists. 6077 if (!AddedTypes.insert(CanonType) || 6078 UserDefinedBinaryOperators.count(std::make_pair(CanonType, 6079 CanonType))) 6080 continue; 6081 6082 QualType ParamTypes[2] = { *Enum, *Enum }; 6083 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 6084 CandidateSet); 6085 } 6086 6087 if (CandidateTypes[ArgIdx].hasNullPtrType()) { 6088 CanQualType NullPtrTy = S.Context.getCanonicalType(S.Context.NullPtrTy); 6089 if (AddedTypes.insert(NullPtrTy) && 6090 !UserDefinedBinaryOperators.count(std::make_pair(NullPtrTy, 6091 NullPtrTy))) { 6092 QualType ParamTypes[2] = { NullPtrTy, NullPtrTy }; 6093 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 6094 CandidateSet); 6095 } 6096 } 6097 } 6098 } 6099 6100 // C++ [over.built]p13: 6101 // 6102 // For every cv-qualified or cv-unqualified object type T 6103 // there exist candidate operator functions of the form 6104 // 6105 // T* operator+(T*, ptrdiff_t); 6106 // T& operator[](T*, ptrdiff_t); [BELOW] 6107 // T* operator-(T*, ptrdiff_t); 6108 // T* operator+(ptrdiff_t, T*); 6109 // T& operator[](ptrdiff_t, T*); [BELOW] 6110 // 6111 // C++ [over.built]p14: 6112 // 6113 // For every T, where T is a pointer to object type, there 6114 // exist candidate operator functions of the form 6115 // 6116 // ptrdiff_t operator-(T, T); 6117 void addBinaryPlusOrMinusPointerOverloads(OverloadedOperatorKind Op) { 6118 /// Set of (canonical) types that we've already handled. 6119 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6120 6121 for (int Arg = 0; Arg < 2; ++Arg) { 6122 QualType AsymetricParamTypes[2] = { 6123 S.Context.getPointerDiffType(), 6124 S.Context.getPointerDiffType(), 6125 }; 6126 for (BuiltinCandidateTypeSet::iterator 6127 Ptr = CandidateTypes[Arg].pointer_begin(), 6128 PtrEnd = CandidateTypes[Arg].pointer_end(); 6129 Ptr != PtrEnd; ++Ptr) { 6130 QualType PointeeTy = (*Ptr)->getPointeeType(); 6131 if (!PointeeTy->isObjectType()) 6132 continue; 6133 6134 AsymetricParamTypes[Arg] = *Ptr; 6135 if (Arg == 0 || Op == OO_Plus) { 6136 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t) 6137 // T* operator+(ptrdiff_t, T*); 6138 S.AddBuiltinCandidate(*Ptr, AsymetricParamTypes, Args, 2, 6139 CandidateSet); 6140 } 6141 if (Op == OO_Minus) { 6142 // ptrdiff_t operator-(T, T); 6143 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 6144 continue; 6145 6146 QualType ParamTypes[2] = { *Ptr, *Ptr }; 6147 S.AddBuiltinCandidate(S.Context.getPointerDiffType(), ParamTypes, 6148 Args, 2, CandidateSet); 6149 } 6150 } 6151 } 6152 } 6153 6154 // C++ [over.built]p12: 6155 // 6156 // For every pair of promoted arithmetic types L and R, there 6157 // exist candidate operator functions of the form 6158 // 6159 // LR operator*(L, R); 6160 // LR operator/(L, R); 6161 // LR operator+(L, R); 6162 // LR operator-(L, R); 6163 // bool operator<(L, R); 6164 // bool operator>(L, R); 6165 // bool operator<=(L, R); 6166 // bool operator>=(L, R); 6167 // bool operator==(L, R); 6168 // bool operator!=(L, R); 6169 // 6170 // where LR is the result of the usual arithmetic conversions 6171 // between types L and R. 6172 // 6173 // C++ [over.built]p24: 6174 // 6175 // For every pair of promoted arithmetic types L and R, there exist 6176 // candidate operator functions of the form 6177 // 6178 // LR operator?(bool, L, R); 6179 // 6180 // where LR is the result of the usual arithmetic conversions 6181 // between types L and R. 6182 // Our candidates ignore the first parameter. 6183 void addGenericBinaryArithmeticOverloads(bool isComparison) { 6184 if (!HasArithmeticOrEnumeralCandidateType) 6185 return; 6186 6187 for (unsigned Left = FirstPromotedArithmeticType; 6188 Left < LastPromotedArithmeticType; ++Left) { 6189 for (unsigned Right = FirstPromotedArithmeticType; 6190 Right < LastPromotedArithmeticType; ++Right) { 6191 QualType LandR[2] = { getArithmeticType(Left), 6192 getArithmeticType(Right) }; 6193 QualType Result = 6194 isComparison ? S.Context.BoolTy 6195 : getUsualArithmeticConversions(Left, Right); 6196 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 6197 } 6198 } 6199 6200 // Extension: Add the binary operators ==, !=, <, <=, >=, >, *, /, and the 6201 // conditional operator for vector types. 6202 for (BuiltinCandidateTypeSet::iterator 6203 Vec1 = CandidateTypes[0].vector_begin(), 6204 Vec1End = CandidateTypes[0].vector_end(); 6205 Vec1 != Vec1End; ++Vec1) { 6206 for (BuiltinCandidateTypeSet::iterator 6207 Vec2 = CandidateTypes[1].vector_begin(), 6208 Vec2End = CandidateTypes[1].vector_end(); 6209 Vec2 != Vec2End; ++Vec2) { 6210 QualType LandR[2] = { *Vec1, *Vec2 }; 6211 QualType Result = S.Context.BoolTy; 6212 if (!isComparison) { 6213 if ((*Vec1)->isExtVectorType() || !(*Vec2)->isExtVectorType()) 6214 Result = *Vec1; 6215 else 6216 Result = *Vec2; 6217 } 6218 6219 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 6220 } 6221 } 6222 } 6223 6224 // C++ [over.built]p17: 6225 // 6226 // For every pair of promoted integral types L and R, there 6227 // exist candidate operator functions of the form 6228 // 6229 // LR operator%(L, R); 6230 // LR operator&(L, R); 6231 // LR operator^(L, R); 6232 // LR operator|(L, R); 6233 // L operator<<(L, R); 6234 // L operator>>(L, R); 6235 // 6236 // where LR is the result of the usual arithmetic conversions 6237 // between types L and R. 6238 void addBinaryBitwiseArithmeticOverloads(OverloadedOperatorKind Op) { 6239 if (!HasArithmeticOrEnumeralCandidateType) 6240 return; 6241 6242 for (unsigned Left = FirstPromotedIntegralType; 6243 Left < LastPromotedIntegralType; ++Left) { 6244 for (unsigned Right = FirstPromotedIntegralType; 6245 Right < LastPromotedIntegralType; ++Right) { 6246 QualType LandR[2] = { getArithmeticType(Left), 6247 getArithmeticType(Right) }; 6248 QualType Result = (Op == OO_LessLess || Op == OO_GreaterGreater) 6249 ? LandR[0] 6250 : getUsualArithmeticConversions(Left, Right); 6251 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 6252 } 6253 } 6254 } 6255 6256 // C++ [over.built]p20: 6257 // 6258 // For every pair (T, VQ), where T is an enumeration or 6259 // pointer to member type and VQ is either volatile or 6260 // empty, there exist candidate operator functions of the form 6261 // 6262 // VQ T& operator=(VQ T&, T); 6263 void addAssignmentMemberPointerOrEnumeralOverloads() { 6264 /// Set of (canonical) types that we've already handled. 6265 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6266 6267 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 6268 for (BuiltinCandidateTypeSet::iterator 6269 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 6270 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 6271 Enum != EnumEnd; ++Enum) { 6272 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 6273 continue; 6274 6275 AddBuiltinAssignmentOperatorCandidates(S, *Enum, Args, 2, 6276 CandidateSet); 6277 } 6278 6279 for (BuiltinCandidateTypeSet::iterator 6280 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 6281 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 6282 MemPtr != MemPtrEnd; ++MemPtr) { 6283 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 6284 continue; 6285 6286 AddBuiltinAssignmentOperatorCandidates(S, *MemPtr, Args, 2, 6287 CandidateSet); 6288 } 6289 } 6290 } 6291 6292 // C++ [over.built]p19: 6293 // 6294 // For every pair (T, VQ), where T is any type and VQ is either 6295 // volatile or empty, there exist candidate operator functions 6296 // of the form 6297 // 6298 // T*VQ& operator=(T*VQ&, T*); 6299 // 6300 // C++ [over.built]p21: 6301 // 6302 // For every pair (T, VQ), where T is a cv-qualified or 6303 // cv-unqualified object type and VQ is either volatile or 6304 // empty, there exist candidate operator functions of the form 6305 // 6306 // T*VQ& operator+=(T*VQ&, ptrdiff_t); 6307 // T*VQ& operator-=(T*VQ&, ptrdiff_t); 6308 void addAssignmentPointerOverloads(bool isEqualOp) { 6309 /// Set of (canonical) types that we've already handled. 6310 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6311 6312 for (BuiltinCandidateTypeSet::iterator 6313 Ptr = CandidateTypes[0].pointer_begin(), 6314 PtrEnd = CandidateTypes[0].pointer_end(); 6315 Ptr != PtrEnd; ++Ptr) { 6316 // If this is operator=, keep track of the builtin candidates we added. 6317 if (isEqualOp) 6318 AddedTypes.insert(S.Context.getCanonicalType(*Ptr)); 6319 else if (!(*Ptr)->getPointeeType()->isObjectType()) 6320 continue; 6321 6322 // non-volatile version 6323 QualType ParamTypes[2] = { 6324 S.Context.getLValueReferenceType(*Ptr), 6325 isEqualOp ? *Ptr : S.Context.getPointerDiffType(), 6326 }; 6327 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6328 /*IsAssigmentOperator=*/ isEqualOp); 6329 6330 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 6331 VisibleTypeConversionsQuals.hasVolatile()) { 6332 // volatile version 6333 ParamTypes[0] = 6334 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 6335 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6336 /*IsAssigmentOperator=*/isEqualOp); 6337 } 6338 } 6339 6340 if (isEqualOp) { 6341 for (BuiltinCandidateTypeSet::iterator 6342 Ptr = CandidateTypes[1].pointer_begin(), 6343 PtrEnd = CandidateTypes[1].pointer_end(); 6344 Ptr != PtrEnd; ++Ptr) { 6345 // Make sure we don't add the same candidate twice. 6346 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 6347 continue; 6348 6349 QualType ParamTypes[2] = { 6350 S.Context.getLValueReferenceType(*Ptr), 6351 *Ptr, 6352 }; 6353 6354 // non-volatile version 6355 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6356 /*IsAssigmentOperator=*/true); 6357 6358 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 6359 VisibleTypeConversionsQuals.hasVolatile()) { 6360 // volatile version 6361 ParamTypes[0] = 6362 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 6363 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6364 CandidateSet, /*IsAssigmentOperator=*/true); 6365 } 6366 } 6367 } 6368 } 6369 6370 // C++ [over.built]p18: 6371 // 6372 // For every triple (L, VQ, R), where L is an arithmetic type, 6373 // VQ is either volatile or empty, and R is a promoted 6374 // arithmetic type, there exist candidate operator functions of 6375 // the form 6376 // 6377 // VQ L& operator=(VQ L&, R); 6378 // VQ L& operator*=(VQ L&, R); 6379 // VQ L& operator/=(VQ L&, R); 6380 // VQ L& operator+=(VQ L&, R); 6381 // VQ L& operator-=(VQ L&, R); 6382 void addAssignmentArithmeticOverloads(bool isEqualOp) { 6383 if (!HasArithmeticOrEnumeralCandidateType) 6384 return; 6385 6386 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) { 6387 for (unsigned Right = FirstPromotedArithmeticType; 6388 Right < LastPromotedArithmeticType; ++Right) { 6389 QualType ParamTypes[2]; 6390 ParamTypes[1] = getArithmeticType(Right); 6391 6392 // Add this built-in operator as a candidate (VQ is empty). 6393 ParamTypes[0] = 6394 S.Context.getLValueReferenceType(getArithmeticType(Left)); 6395 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6396 /*IsAssigmentOperator=*/isEqualOp); 6397 6398 // Add this built-in operator as a candidate (VQ is 'volatile'). 6399 if (VisibleTypeConversionsQuals.hasVolatile()) { 6400 ParamTypes[0] = 6401 S.Context.getVolatileType(getArithmeticType(Left)); 6402 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 6403 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6404 CandidateSet, 6405 /*IsAssigmentOperator=*/isEqualOp); 6406 } 6407 } 6408 } 6409 6410 // Extension: Add the binary operators =, +=, -=, *=, /= for vector types. 6411 for (BuiltinCandidateTypeSet::iterator 6412 Vec1 = CandidateTypes[0].vector_begin(), 6413 Vec1End = CandidateTypes[0].vector_end(); 6414 Vec1 != Vec1End; ++Vec1) { 6415 for (BuiltinCandidateTypeSet::iterator 6416 Vec2 = CandidateTypes[1].vector_begin(), 6417 Vec2End = CandidateTypes[1].vector_end(); 6418 Vec2 != Vec2End; ++Vec2) { 6419 QualType ParamTypes[2]; 6420 ParamTypes[1] = *Vec2; 6421 // Add this built-in operator as a candidate (VQ is empty). 6422 ParamTypes[0] = S.Context.getLValueReferenceType(*Vec1); 6423 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6424 /*IsAssigmentOperator=*/isEqualOp); 6425 6426 // Add this built-in operator as a candidate (VQ is 'volatile'). 6427 if (VisibleTypeConversionsQuals.hasVolatile()) { 6428 ParamTypes[0] = S.Context.getVolatileType(*Vec1); 6429 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 6430 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6431 CandidateSet, 6432 /*IsAssigmentOperator=*/isEqualOp); 6433 } 6434 } 6435 } 6436 } 6437 6438 // C++ [over.built]p22: 6439 // 6440 // For every triple (L, VQ, R), where L is an integral type, VQ 6441 // is either volatile or empty, and R is a promoted integral 6442 // type, there exist candidate operator functions of the form 6443 // 6444 // VQ L& operator%=(VQ L&, R); 6445 // VQ L& operator<<=(VQ L&, R); 6446 // VQ L& operator>>=(VQ L&, R); 6447 // VQ L& operator&=(VQ L&, R); 6448 // VQ L& operator^=(VQ L&, R); 6449 // VQ L& operator|=(VQ L&, R); 6450 void addAssignmentIntegralOverloads() { 6451 if (!HasArithmeticOrEnumeralCandidateType) 6452 return; 6453 6454 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) { 6455 for (unsigned Right = FirstPromotedIntegralType; 6456 Right < LastPromotedIntegralType; ++Right) { 6457 QualType ParamTypes[2]; 6458 ParamTypes[1] = getArithmeticType(Right); 6459 6460 // Add this built-in operator as a candidate (VQ is empty). 6461 ParamTypes[0] = 6462 S.Context.getLValueReferenceType(getArithmeticType(Left)); 6463 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 6464 if (VisibleTypeConversionsQuals.hasVolatile()) { 6465 // Add this built-in operator as a candidate (VQ is 'volatile'). 6466 ParamTypes[0] = getArithmeticType(Left); 6467 ParamTypes[0] = S.Context.getVolatileType(ParamTypes[0]); 6468 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 6469 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6470 CandidateSet); 6471 } 6472 } 6473 } 6474 } 6475 6476 // C++ [over.operator]p23: 6477 // 6478 // There also exist candidate operator functions of the form 6479 // 6480 // bool operator!(bool); 6481 // bool operator&&(bool, bool); 6482 // bool operator||(bool, bool); 6483 void addExclaimOverload() { 6484 QualType ParamTy = S.Context.BoolTy; 6485 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet, 6486 /*IsAssignmentOperator=*/false, 6487 /*NumContextualBoolArguments=*/1); 6488 } 6489 void addAmpAmpOrPipePipeOverload() { 6490 QualType ParamTypes[2] = { S.Context.BoolTy, S.Context.BoolTy }; 6491 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, CandidateSet, 6492 /*IsAssignmentOperator=*/false, 6493 /*NumContextualBoolArguments=*/2); 6494 } 6495 6496 // C++ [over.built]p13: 6497 // 6498 // For every cv-qualified or cv-unqualified object type T there 6499 // exist candidate operator functions of the form 6500 // 6501 // T* operator+(T*, ptrdiff_t); [ABOVE] 6502 // T& operator[](T*, ptrdiff_t); 6503 // T* operator-(T*, ptrdiff_t); [ABOVE] 6504 // T* operator+(ptrdiff_t, T*); [ABOVE] 6505 // T& operator[](ptrdiff_t, T*); 6506 void addSubscriptOverloads() { 6507 for (BuiltinCandidateTypeSet::iterator 6508 Ptr = CandidateTypes[0].pointer_begin(), 6509 PtrEnd = CandidateTypes[0].pointer_end(); 6510 Ptr != PtrEnd; ++Ptr) { 6511 QualType ParamTypes[2] = { *Ptr, S.Context.getPointerDiffType() }; 6512 QualType PointeeType = (*Ptr)->getPointeeType(); 6513 if (!PointeeType->isObjectType()) 6514 continue; 6515 6516 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 6517 6518 // T& operator[](T*, ptrdiff_t) 6519 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6520 } 6521 6522 for (BuiltinCandidateTypeSet::iterator 6523 Ptr = CandidateTypes[1].pointer_begin(), 6524 PtrEnd = CandidateTypes[1].pointer_end(); 6525 Ptr != PtrEnd; ++Ptr) { 6526 QualType ParamTypes[2] = { S.Context.getPointerDiffType(), *Ptr }; 6527 QualType PointeeType = (*Ptr)->getPointeeType(); 6528 if (!PointeeType->isObjectType()) 6529 continue; 6530 6531 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 6532 6533 // T& operator[](ptrdiff_t, T*) 6534 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6535 } 6536 } 6537 6538 // C++ [over.built]p11: 6539 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type, 6540 // C1 is the same type as C2 or is a derived class of C2, T is an object 6541 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs, 6542 // there exist candidate operator functions of the form 6543 // 6544 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*); 6545 // 6546 // where CV12 is the union of CV1 and CV2. 6547 void addArrowStarOverloads() { 6548 for (BuiltinCandidateTypeSet::iterator 6549 Ptr = CandidateTypes[0].pointer_begin(), 6550 PtrEnd = CandidateTypes[0].pointer_end(); 6551 Ptr != PtrEnd; ++Ptr) { 6552 QualType C1Ty = (*Ptr); 6553 QualType C1; 6554 QualifierCollector Q1; 6555 C1 = QualType(Q1.strip(C1Ty->getPointeeType()), 0); 6556 if (!isa<RecordType>(C1)) 6557 continue; 6558 // heuristic to reduce number of builtin candidates in the set. 6559 // Add volatile/restrict version only if there are conversions to a 6560 // volatile/restrict type. 6561 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile()) 6562 continue; 6563 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict()) 6564 continue; 6565 for (BuiltinCandidateTypeSet::iterator 6566 MemPtr = CandidateTypes[1].member_pointer_begin(), 6567 MemPtrEnd = CandidateTypes[1].member_pointer_end(); 6568 MemPtr != MemPtrEnd; ++MemPtr) { 6569 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr); 6570 QualType C2 = QualType(mptr->getClass(), 0); 6571 C2 = C2.getUnqualifiedType(); 6572 if (C1 != C2 && !S.IsDerivedFrom(C1, C2)) 6573 break; 6574 QualType ParamTypes[2] = { *Ptr, *MemPtr }; 6575 // build CV12 T& 6576 QualType T = mptr->getPointeeType(); 6577 if (!VisibleTypeConversionsQuals.hasVolatile() && 6578 T.isVolatileQualified()) 6579 continue; 6580 if (!VisibleTypeConversionsQuals.hasRestrict() && 6581 T.isRestrictQualified()) 6582 continue; 6583 T = Q1.apply(S.Context, T); 6584 QualType ResultTy = S.Context.getLValueReferenceType(T); 6585 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6586 } 6587 } 6588 } 6589 6590 // Note that we don't consider the first argument, since it has been 6591 // contextually converted to bool long ago. The candidates below are 6592 // therefore added as binary. 6593 // 6594 // C++ [over.built]p25: 6595 // For every type T, where T is a pointer, pointer-to-member, or scoped 6596 // enumeration type, there exist candidate operator functions of the form 6597 // 6598 // T operator?(bool, T, T); 6599 // 6600 void addConditionalOperatorOverloads() { 6601 /// Set of (canonical) types that we've already handled. 6602 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6603 6604 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 6605 for (BuiltinCandidateTypeSet::iterator 6606 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 6607 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 6608 Ptr != PtrEnd; ++Ptr) { 6609 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 6610 continue; 6611 6612 QualType ParamTypes[2] = { *Ptr, *Ptr }; 6613 S.AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 6614 } 6615 6616 for (BuiltinCandidateTypeSet::iterator 6617 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 6618 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 6619 MemPtr != MemPtrEnd; ++MemPtr) { 6620 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 6621 continue; 6622 6623 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 6624 S.AddBuiltinCandidate(*MemPtr, ParamTypes, Args, 2, CandidateSet); 6625 } 6626 6627 if (S.getLangOptions().CPlusPlus0x) { 6628 for (BuiltinCandidateTypeSet::iterator 6629 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 6630 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 6631 Enum != EnumEnd; ++Enum) { 6632 if (!(*Enum)->getAs<EnumType>()->getDecl()->isScoped()) 6633 continue; 6634 6635 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 6636 continue; 6637 6638 QualType ParamTypes[2] = { *Enum, *Enum }; 6639 S.AddBuiltinCandidate(*Enum, ParamTypes, Args, 2, CandidateSet); 6640 } 6641 } 6642 } 6643 } 6644}; 6645 6646} // end anonymous namespace 6647 6648/// AddBuiltinOperatorCandidates - Add the appropriate built-in 6649/// operator overloads to the candidate set (C++ [over.built]), based 6650/// on the operator @p Op and the arguments given. For example, if the 6651/// operator is a binary '+', this routine might add "int 6652/// operator+(int, int)" to cover integer addition. 6653void 6654Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op, 6655 SourceLocation OpLoc, 6656 Expr **Args, unsigned NumArgs, 6657 OverloadCandidateSet& CandidateSet) { 6658 // Find all of the types that the arguments can convert to, but only 6659 // if the operator we're looking at has built-in operator candidates 6660 // that make use of these types. Also record whether we encounter non-record 6661 // candidate types or either arithmetic or enumeral candidate types. 6662 Qualifiers VisibleTypeConversionsQuals; 6663 VisibleTypeConversionsQuals.addConst(); 6664 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 6665 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]); 6666 6667 bool HasNonRecordCandidateType = false; 6668 bool HasArithmeticOrEnumeralCandidateType = false; 6669 SmallVector<BuiltinCandidateTypeSet, 2> CandidateTypes; 6670 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6671 CandidateTypes.push_back(BuiltinCandidateTypeSet(*this)); 6672 CandidateTypes[ArgIdx].AddTypesConvertedFrom(Args[ArgIdx]->getType(), 6673 OpLoc, 6674 true, 6675 (Op == OO_Exclaim || 6676 Op == OO_AmpAmp || 6677 Op == OO_PipePipe), 6678 VisibleTypeConversionsQuals); 6679 HasNonRecordCandidateType = HasNonRecordCandidateType || 6680 CandidateTypes[ArgIdx].hasNonRecordTypes(); 6681 HasArithmeticOrEnumeralCandidateType = 6682 HasArithmeticOrEnumeralCandidateType || 6683 CandidateTypes[ArgIdx].hasArithmeticOrEnumeralTypes(); 6684 } 6685 6686 // Exit early when no non-record types have been added to the candidate set 6687 // for any of the arguments to the operator. 6688 // 6689 // We can't exit early for !, ||, or &&, since there we have always have 6690 // 'bool' overloads. 6691 if (!HasNonRecordCandidateType && 6692 !(Op == OO_Exclaim || Op == OO_AmpAmp || Op == OO_PipePipe)) 6693 return; 6694 6695 // Setup an object to manage the common state for building overloads. 6696 BuiltinOperatorOverloadBuilder OpBuilder(*this, Args, NumArgs, 6697 VisibleTypeConversionsQuals, 6698 HasArithmeticOrEnumeralCandidateType, 6699 CandidateTypes, CandidateSet); 6700 6701 // Dispatch over the operation to add in only those overloads which apply. 6702 switch (Op) { 6703 case OO_None: 6704 case NUM_OVERLOADED_OPERATORS: 6705 llvm_unreachable("Expected an overloaded operator"); 6706 6707 case OO_New: 6708 case OO_Delete: 6709 case OO_Array_New: 6710 case OO_Array_Delete: 6711 case OO_Call: 6712 llvm_unreachable( 6713 "Special operators don't use AddBuiltinOperatorCandidates"); 6714 6715 case OO_Comma: 6716 case OO_Arrow: 6717 // C++ [over.match.oper]p3: 6718 // -- For the operator ',', the unary operator '&', or the 6719 // operator '->', the built-in candidates set is empty. 6720 break; 6721 6722 case OO_Plus: // '+' is either unary or binary 6723 if (NumArgs == 1) 6724 OpBuilder.addUnaryPlusPointerOverloads(); 6725 // Fall through. 6726 6727 case OO_Minus: // '-' is either unary or binary 6728 if (NumArgs == 1) { 6729 OpBuilder.addUnaryPlusOrMinusArithmeticOverloads(); 6730 } else { 6731 OpBuilder.addBinaryPlusOrMinusPointerOverloads(Op); 6732 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6733 } 6734 break; 6735 6736 case OO_Star: // '*' is either unary or binary 6737 if (NumArgs == 1) 6738 OpBuilder.addUnaryStarPointerOverloads(); 6739 else 6740 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6741 break; 6742 6743 case OO_Slash: 6744 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6745 break; 6746 6747 case OO_PlusPlus: 6748 case OO_MinusMinus: 6749 OpBuilder.addPlusPlusMinusMinusArithmeticOverloads(Op); 6750 OpBuilder.addPlusPlusMinusMinusPointerOverloads(); 6751 break; 6752 6753 case OO_EqualEqual: 6754 case OO_ExclaimEqual: 6755 OpBuilder.addEqualEqualOrNotEqualMemberPointerOverloads(); 6756 // Fall through. 6757 6758 case OO_Less: 6759 case OO_Greater: 6760 case OO_LessEqual: 6761 case OO_GreaterEqual: 6762 OpBuilder.addRelationalPointerOrEnumeralOverloads(); 6763 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/true); 6764 break; 6765 6766 case OO_Percent: 6767 case OO_Caret: 6768 case OO_Pipe: 6769 case OO_LessLess: 6770 case OO_GreaterGreater: 6771 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6772 break; 6773 6774 case OO_Amp: // '&' is either unary or binary 6775 if (NumArgs == 1) 6776 // C++ [over.match.oper]p3: 6777 // -- For the operator ',', the unary operator '&', or the 6778 // operator '->', the built-in candidates set is empty. 6779 break; 6780 6781 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6782 break; 6783 6784 case OO_Tilde: 6785 OpBuilder.addUnaryTildePromotedIntegralOverloads(); 6786 break; 6787 6788 case OO_Equal: 6789 OpBuilder.addAssignmentMemberPointerOrEnumeralOverloads(); 6790 // Fall through. 6791 6792 case OO_PlusEqual: 6793 case OO_MinusEqual: 6794 OpBuilder.addAssignmentPointerOverloads(Op == OO_Equal); 6795 // Fall through. 6796 6797 case OO_StarEqual: 6798 case OO_SlashEqual: 6799 OpBuilder.addAssignmentArithmeticOverloads(Op == OO_Equal); 6800 break; 6801 6802 case OO_PercentEqual: 6803 case OO_LessLessEqual: 6804 case OO_GreaterGreaterEqual: 6805 case OO_AmpEqual: 6806 case OO_CaretEqual: 6807 case OO_PipeEqual: 6808 OpBuilder.addAssignmentIntegralOverloads(); 6809 break; 6810 6811 case OO_Exclaim: 6812 OpBuilder.addExclaimOverload(); 6813 break; 6814 6815 case OO_AmpAmp: 6816 case OO_PipePipe: 6817 OpBuilder.addAmpAmpOrPipePipeOverload(); 6818 break; 6819 6820 case OO_Subscript: 6821 OpBuilder.addSubscriptOverloads(); 6822 break; 6823 6824 case OO_ArrowStar: 6825 OpBuilder.addArrowStarOverloads(); 6826 break; 6827 6828 case OO_Conditional: 6829 OpBuilder.addConditionalOperatorOverloads(); 6830 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6831 break; 6832 } 6833} 6834 6835/// \brief Add function candidates found via argument-dependent lookup 6836/// to the set of overloading candidates. 6837/// 6838/// This routine performs argument-dependent name lookup based on the 6839/// given function name (which may also be an operator name) and adds 6840/// all of the overload candidates found by ADL to the overload 6841/// candidate set (C++ [basic.lookup.argdep]). 6842void 6843Sema::AddArgumentDependentLookupCandidates(DeclarationName Name, 6844 bool Operator, 6845 Expr **Args, unsigned NumArgs, 6846 TemplateArgumentListInfo *ExplicitTemplateArgs, 6847 OverloadCandidateSet& CandidateSet, 6848 bool PartialOverloading, 6849 bool StdNamespaceIsAssociated) { 6850 ADLResult Fns; 6851 6852 // FIXME: This approach for uniquing ADL results (and removing 6853 // redundant candidates from the set) relies on pointer-equality, 6854 // which means we need to key off the canonical decl. However, 6855 // always going back to the canonical decl might not get us the 6856 // right set of default arguments. What default arguments are 6857 // we supposed to consider on ADL candidates, anyway? 6858 6859 // FIXME: Pass in the explicit template arguments? 6860 ArgumentDependentLookup(Name, Operator, Args, NumArgs, Fns, 6861 StdNamespaceIsAssociated); 6862 6863 // Erase all of the candidates we already knew about. 6864 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 6865 CandEnd = CandidateSet.end(); 6866 Cand != CandEnd; ++Cand) 6867 if (Cand->Function) { 6868 Fns.erase(Cand->Function); 6869 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 6870 Fns.erase(FunTmpl); 6871 } 6872 6873 // For each of the ADL candidates we found, add it to the overload 6874 // set. 6875 for (ADLResult::iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 6876 DeclAccessPair FoundDecl = DeclAccessPair::make(*I, AS_none); 6877 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { 6878 if (ExplicitTemplateArgs) 6879 continue; 6880 6881 AddOverloadCandidate(FD, FoundDecl, Args, NumArgs, CandidateSet, 6882 false, PartialOverloading); 6883 } else 6884 AddTemplateOverloadCandidate(cast<FunctionTemplateDecl>(*I), 6885 FoundDecl, ExplicitTemplateArgs, 6886 Args, NumArgs, CandidateSet); 6887 } 6888} 6889 6890/// isBetterOverloadCandidate - Determines whether the first overload 6891/// candidate is a better candidate than the second (C++ 13.3.3p1). 6892bool 6893isBetterOverloadCandidate(Sema &S, 6894 const OverloadCandidate &Cand1, 6895 const OverloadCandidate &Cand2, 6896 SourceLocation Loc, 6897 bool UserDefinedConversion) { 6898 // Define viable functions to be better candidates than non-viable 6899 // functions. 6900 if (!Cand2.Viable) 6901 return Cand1.Viable; 6902 else if (!Cand1.Viable) 6903 return false; 6904 6905 // C++ [over.match.best]p1: 6906 // 6907 // -- if F is a static member function, ICS1(F) is defined such 6908 // that ICS1(F) is neither better nor worse than ICS1(G) for 6909 // any function G, and, symmetrically, ICS1(G) is neither 6910 // better nor worse than ICS1(F). 6911 unsigned StartArg = 0; 6912 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument) 6913 StartArg = 1; 6914 6915 // C++ [over.match.best]p1: 6916 // A viable function F1 is defined to be a better function than another 6917 // viable function F2 if for all arguments i, ICSi(F1) is not a worse 6918 // conversion sequence than ICSi(F2), and then... 6919 unsigned NumArgs = Cand1.Conversions.size(); 6920 assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch"); 6921 bool HasBetterConversion = false; 6922 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) { 6923 switch (CompareImplicitConversionSequences(S, 6924 Cand1.Conversions[ArgIdx], 6925 Cand2.Conversions[ArgIdx])) { 6926 case ImplicitConversionSequence::Better: 6927 // Cand1 has a better conversion sequence. 6928 HasBetterConversion = true; 6929 break; 6930 6931 case ImplicitConversionSequence::Worse: 6932 // Cand1 can't be better than Cand2. 6933 return false; 6934 6935 case ImplicitConversionSequence::Indistinguishable: 6936 // Do nothing. 6937 break; 6938 } 6939 } 6940 6941 // -- for some argument j, ICSj(F1) is a better conversion sequence than 6942 // ICSj(F2), or, if not that, 6943 if (HasBetterConversion) 6944 return true; 6945 6946 // - F1 is a non-template function and F2 is a function template 6947 // specialization, or, if not that, 6948 if ((!Cand1.Function || !Cand1.Function->getPrimaryTemplate()) && 6949 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 6950 return true; 6951 6952 // -- F1 and F2 are function template specializations, and the function 6953 // template for F1 is more specialized than the template for F2 6954 // according to the partial ordering rules described in 14.5.5.2, or, 6955 // if not that, 6956 if (Cand1.Function && Cand1.Function->getPrimaryTemplate() && 6957 Cand2.Function && Cand2.Function->getPrimaryTemplate()) { 6958 if (FunctionTemplateDecl *BetterTemplate 6959 = S.getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(), 6960 Cand2.Function->getPrimaryTemplate(), 6961 Loc, 6962 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion 6963 : TPOC_Call, 6964 Cand1.ExplicitCallArguments)) 6965 return BetterTemplate == Cand1.Function->getPrimaryTemplate(); 6966 } 6967 6968 // -- the context is an initialization by user-defined conversion 6969 // (see 8.5, 13.3.1.5) and the standard conversion sequence 6970 // from the return type of F1 to the destination type (i.e., 6971 // the type of the entity being initialized) is a better 6972 // conversion sequence than the standard conversion sequence 6973 // from the return type of F2 to the destination type. 6974 if (UserDefinedConversion && Cand1.Function && Cand2.Function && 6975 isa<CXXConversionDecl>(Cand1.Function) && 6976 isa<CXXConversionDecl>(Cand2.Function)) { 6977 switch (CompareStandardConversionSequences(S, 6978 Cand1.FinalConversion, 6979 Cand2.FinalConversion)) { 6980 case ImplicitConversionSequence::Better: 6981 // Cand1 has a better conversion sequence. 6982 return true; 6983 6984 case ImplicitConversionSequence::Worse: 6985 // Cand1 can't be better than Cand2. 6986 return false; 6987 6988 case ImplicitConversionSequence::Indistinguishable: 6989 // Do nothing 6990 break; 6991 } 6992 } 6993 6994 return false; 6995} 6996 6997/// \brief Computes the best viable function (C++ 13.3.3) 6998/// within an overload candidate set. 6999/// 7000/// \param CandidateSet the set of candidate functions. 7001/// 7002/// \param Loc the location of the function name (or operator symbol) for 7003/// which overload resolution occurs. 7004/// 7005/// \param Best f overload resolution was successful or found a deleted 7006/// function, Best points to the candidate function found. 7007/// 7008/// \returns The result of overload resolution. 7009OverloadingResult 7010OverloadCandidateSet::BestViableFunction(Sema &S, SourceLocation Loc, 7011 iterator &Best, 7012 bool UserDefinedConversion) { 7013 // Find the best viable function. 7014 Best = end(); 7015 for (iterator Cand = begin(); Cand != end(); ++Cand) { 7016 if (Cand->Viable) 7017 if (Best == end() || isBetterOverloadCandidate(S, *Cand, *Best, Loc, 7018 UserDefinedConversion)) 7019 Best = Cand; 7020 } 7021 7022 // If we didn't find any viable functions, abort. 7023 if (Best == end()) 7024 return OR_No_Viable_Function; 7025 7026 // Make sure that this function is better than every other viable 7027 // function. If not, we have an ambiguity. 7028 for (iterator Cand = begin(); Cand != end(); ++Cand) { 7029 if (Cand->Viable && 7030 Cand != Best && 7031 !isBetterOverloadCandidate(S, *Best, *Cand, Loc, 7032 UserDefinedConversion)) { 7033 Best = end(); 7034 return OR_Ambiguous; 7035 } 7036 } 7037 7038 // Best is the best viable function. 7039 if (Best->Function && 7040 (Best->Function->isDeleted() || 7041 S.isFunctionConsideredUnavailable(Best->Function))) 7042 return OR_Deleted; 7043 7044 return OR_Success; 7045} 7046 7047namespace { 7048 7049enum OverloadCandidateKind { 7050 oc_function, 7051 oc_method, 7052 oc_constructor, 7053 oc_function_template, 7054 oc_method_template, 7055 oc_constructor_template, 7056 oc_implicit_default_constructor, 7057 oc_implicit_copy_constructor, 7058 oc_implicit_move_constructor, 7059 oc_implicit_copy_assignment, 7060 oc_implicit_move_assignment, 7061 oc_implicit_inherited_constructor 7062}; 7063 7064OverloadCandidateKind ClassifyOverloadCandidate(Sema &S, 7065 FunctionDecl *Fn, 7066 std::string &Description) { 7067 bool isTemplate = false; 7068 7069 if (FunctionTemplateDecl *FunTmpl = Fn->getPrimaryTemplate()) { 7070 isTemplate = true; 7071 Description = S.getTemplateArgumentBindingsText( 7072 FunTmpl->getTemplateParameters(), *Fn->getTemplateSpecializationArgs()); 7073 } 7074 7075 if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn)) { 7076 if (!Ctor->isImplicit()) 7077 return isTemplate ? oc_constructor_template : oc_constructor; 7078 7079 if (Ctor->getInheritedConstructor()) 7080 return oc_implicit_inherited_constructor; 7081 7082 if (Ctor->isDefaultConstructor()) 7083 return oc_implicit_default_constructor; 7084 7085 if (Ctor->isMoveConstructor()) 7086 return oc_implicit_move_constructor; 7087 7088 assert(Ctor->isCopyConstructor() && 7089 "unexpected sort of implicit constructor"); 7090 return oc_implicit_copy_constructor; 7091 } 7092 7093 if (CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Fn)) { 7094 // This actually gets spelled 'candidate function' for now, but 7095 // it doesn't hurt to split it out. 7096 if (!Meth->isImplicit()) 7097 return isTemplate ? oc_method_template : oc_method; 7098 7099 if (Meth->isMoveAssignmentOperator()) 7100 return oc_implicit_move_assignment; 7101 7102 assert(Meth->isCopyAssignmentOperator() 7103 && "implicit method is not copy assignment operator?"); 7104 return oc_implicit_copy_assignment; 7105 } 7106 7107 return isTemplate ? oc_function_template : oc_function; 7108} 7109 7110void MaybeEmitInheritedConstructorNote(Sema &S, FunctionDecl *Fn) { 7111 const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn); 7112 if (!Ctor) return; 7113 7114 Ctor = Ctor->getInheritedConstructor(); 7115 if (!Ctor) return; 7116 7117 S.Diag(Ctor->getLocation(), diag::note_ovl_candidate_inherited_constructor); 7118} 7119 7120} // end anonymous namespace 7121 7122// Notes the location of an overload candidate. 7123void Sema::NoteOverloadCandidate(FunctionDecl *Fn, QualType DestType) { 7124 std::string FnDesc; 7125 OverloadCandidateKind K = ClassifyOverloadCandidate(*this, Fn, FnDesc); 7126 PartialDiagnostic PD = PDiag(diag::note_ovl_candidate) 7127 << (unsigned) K << FnDesc; 7128 HandleFunctionTypeMismatch(PD, Fn->getType(), DestType); 7129 Diag(Fn->getLocation(), PD); 7130 MaybeEmitInheritedConstructorNote(*this, Fn); 7131} 7132 7133//Notes the location of all overload candidates designated through 7134// OverloadedExpr 7135void Sema::NoteAllOverloadCandidates(Expr* OverloadedExpr, QualType DestType) { 7136 assert(OverloadedExpr->getType() == Context.OverloadTy); 7137 7138 OverloadExpr::FindResult Ovl = OverloadExpr::find(OverloadedExpr); 7139 OverloadExpr *OvlExpr = Ovl.Expression; 7140 7141 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 7142 IEnd = OvlExpr->decls_end(); 7143 I != IEnd; ++I) { 7144 if (FunctionTemplateDecl *FunTmpl = 7145 dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()) ) { 7146 NoteOverloadCandidate(FunTmpl->getTemplatedDecl(), DestType); 7147 } else if (FunctionDecl *Fun 7148 = dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()) ) { 7149 NoteOverloadCandidate(Fun, DestType); 7150 } 7151 } 7152} 7153 7154/// Diagnoses an ambiguous conversion. The partial diagnostic is the 7155/// "lead" diagnostic; it will be given two arguments, the source and 7156/// target types of the conversion. 7157void ImplicitConversionSequence::DiagnoseAmbiguousConversion( 7158 Sema &S, 7159 SourceLocation CaretLoc, 7160 const PartialDiagnostic &PDiag) const { 7161 S.Diag(CaretLoc, PDiag) 7162 << Ambiguous.getFromType() << Ambiguous.getToType(); 7163 for (AmbiguousConversionSequence::const_iterator 7164 I = Ambiguous.begin(), E = Ambiguous.end(); I != E; ++I) { 7165 S.NoteOverloadCandidate(*I); 7166 } 7167} 7168 7169namespace { 7170 7171void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, unsigned I) { 7172 const ImplicitConversionSequence &Conv = Cand->Conversions[I]; 7173 assert(Conv.isBad()); 7174 assert(Cand->Function && "for now, candidate must be a function"); 7175 FunctionDecl *Fn = Cand->Function; 7176 7177 // There's a conversion slot for the object argument if this is a 7178 // non-constructor method. Note that 'I' corresponds the 7179 // conversion-slot index. 7180 bool isObjectArgument = false; 7181 if (isa<CXXMethodDecl>(Fn) && !isa<CXXConstructorDecl>(Fn)) { 7182 if (I == 0) 7183 isObjectArgument = true; 7184 else 7185 I--; 7186 } 7187 7188 std::string FnDesc; 7189 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 7190 7191 Expr *FromExpr = Conv.Bad.FromExpr; 7192 QualType FromTy = Conv.Bad.getFromType(); 7193 QualType ToTy = Conv.Bad.getToType(); 7194 7195 if (FromTy == S.Context.OverloadTy) { 7196 assert(FromExpr && "overload set argument came from implicit argument?"); 7197 Expr *E = FromExpr->IgnoreParens(); 7198 if (isa<UnaryOperator>(E)) 7199 E = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens(); 7200 DeclarationName Name = cast<OverloadExpr>(E)->getName(); 7201 7202 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_overload) 7203 << (unsigned) FnKind << FnDesc 7204 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7205 << ToTy << Name << I+1; 7206 MaybeEmitInheritedConstructorNote(S, Fn); 7207 return; 7208 } 7209 7210 // Do some hand-waving analysis to see if the non-viability is due 7211 // to a qualifier mismatch. 7212 CanQualType CFromTy = S.Context.getCanonicalType(FromTy); 7213 CanQualType CToTy = S.Context.getCanonicalType(ToTy); 7214 if (CanQual<ReferenceType> RT = CToTy->getAs<ReferenceType>()) 7215 CToTy = RT->getPointeeType(); 7216 else { 7217 // TODO: detect and diagnose the full richness of const mismatches. 7218 if (CanQual<PointerType> FromPT = CFromTy->getAs<PointerType>()) 7219 if (CanQual<PointerType> ToPT = CToTy->getAs<PointerType>()) 7220 CFromTy = FromPT->getPointeeType(), CToTy = ToPT->getPointeeType(); 7221 } 7222 7223 if (CToTy.getUnqualifiedType() == CFromTy.getUnqualifiedType() && 7224 !CToTy.isAtLeastAsQualifiedAs(CFromTy)) { 7225 // It is dumb that we have to do this here. 7226 while (isa<ArrayType>(CFromTy)) 7227 CFromTy = CFromTy->getAs<ArrayType>()->getElementType(); 7228 while (isa<ArrayType>(CToTy)) 7229 CToTy = CFromTy->getAs<ArrayType>()->getElementType(); 7230 7231 Qualifiers FromQs = CFromTy.getQualifiers(); 7232 Qualifiers ToQs = CToTy.getQualifiers(); 7233 7234 if (FromQs.getAddressSpace() != ToQs.getAddressSpace()) { 7235 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_addrspace) 7236 << (unsigned) FnKind << FnDesc 7237 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7238 << FromTy 7239 << FromQs.getAddressSpace() << ToQs.getAddressSpace() 7240 << (unsigned) isObjectArgument << I+1; 7241 MaybeEmitInheritedConstructorNote(S, Fn); 7242 return; 7243 } 7244 7245 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) { 7246 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_ownership) 7247 << (unsigned) FnKind << FnDesc 7248 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7249 << FromTy 7250 << FromQs.getObjCLifetime() << ToQs.getObjCLifetime() 7251 << (unsigned) isObjectArgument << I+1; 7252 MaybeEmitInheritedConstructorNote(S, Fn); 7253 return; 7254 } 7255 7256 if (FromQs.getObjCGCAttr() != ToQs.getObjCGCAttr()) { 7257 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_gc) 7258 << (unsigned) FnKind << FnDesc 7259 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7260 << FromTy 7261 << FromQs.getObjCGCAttr() << ToQs.getObjCGCAttr() 7262 << (unsigned) isObjectArgument << I+1; 7263 MaybeEmitInheritedConstructorNote(S, Fn); 7264 return; 7265 } 7266 7267 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 7268 assert(CVR && "unexpected qualifiers mismatch"); 7269 7270 if (isObjectArgument) { 7271 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr_this) 7272 << (unsigned) FnKind << FnDesc 7273 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7274 << FromTy << (CVR - 1); 7275 } else { 7276 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr) 7277 << (unsigned) FnKind << FnDesc 7278 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7279 << FromTy << (CVR - 1) << I+1; 7280 } 7281 MaybeEmitInheritedConstructorNote(S, Fn); 7282 return; 7283 } 7284 7285 // Special diagnostic for failure to convert an initializer list, since 7286 // telling the user that it has type void is not useful. 7287 if (FromExpr && isa<InitListExpr>(FromExpr)) { 7288 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_list_argument) 7289 << (unsigned) FnKind << FnDesc 7290 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7291 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 7292 MaybeEmitInheritedConstructorNote(S, Fn); 7293 return; 7294 } 7295 7296 // Diagnose references or pointers to incomplete types differently, 7297 // since it's far from impossible that the incompleteness triggered 7298 // the failure. 7299 QualType TempFromTy = FromTy.getNonReferenceType(); 7300 if (const PointerType *PTy = TempFromTy->getAs<PointerType>()) 7301 TempFromTy = PTy->getPointeeType(); 7302 if (TempFromTy->isIncompleteType()) { 7303 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv_incomplete) 7304 << (unsigned) FnKind << FnDesc 7305 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7306 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 7307 MaybeEmitInheritedConstructorNote(S, Fn); 7308 return; 7309 } 7310 7311 // Diagnose base -> derived pointer conversions. 7312 unsigned BaseToDerivedConversion = 0; 7313 if (const PointerType *FromPtrTy = FromTy->getAs<PointerType>()) { 7314 if (const PointerType *ToPtrTy = ToTy->getAs<PointerType>()) { 7315 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 7316 FromPtrTy->getPointeeType()) && 7317 !FromPtrTy->getPointeeType()->isIncompleteType() && 7318 !ToPtrTy->getPointeeType()->isIncompleteType() && 7319 S.IsDerivedFrom(ToPtrTy->getPointeeType(), 7320 FromPtrTy->getPointeeType())) 7321 BaseToDerivedConversion = 1; 7322 } 7323 } else if (const ObjCObjectPointerType *FromPtrTy 7324 = FromTy->getAs<ObjCObjectPointerType>()) { 7325 if (const ObjCObjectPointerType *ToPtrTy 7326 = ToTy->getAs<ObjCObjectPointerType>()) 7327 if (const ObjCInterfaceDecl *FromIface = FromPtrTy->getInterfaceDecl()) 7328 if (const ObjCInterfaceDecl *ToIface = ToPtrTy->getInterfaceDecl()) 7329 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 7330 FromPtrTy->getPointeeType()) && 7331 FromIface->isSuperClassOf(ToIface)) 7332 BaseToDerivedConversion = 2; 7333 } else if (const ReferenceType *ToRefTy = ToTy->getAs<ReferenceType>()) { 7334 if (ToRefTy->getPointeeType().isAtLeastAsQualifiedAs(FromTy) && 7335 !FromTy->isIncompleteType() && 7336 !ToRefTy->getPointeeType()->isIncompleteType() && 7337 S.IsDerivedFrom(ToRefTy->getPointeeType(), FromTy)) 7338 BaseToDerivedConversion = 3; 7339 } 7340 7341 if (BaseToDerivedConversion) { 7342 S.Diag(Fn->getLocation(), 7343 diag::note_ovl_candidate_bad_base_to_derived_conv) 7344 << (unsigned) FnKind << FnDesc 7345 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7346 << (BaseToDerivedConversion - 1) 7347 << FromTy << ToTy << I+1; 7348 MaybeEmitInheritedConstructorNote(S, Fn); 7349 return; 7350 } 7351 7352 if (isa<ObjCObjectPointerType>(CFromTy) && 7353 isa<PointerType>(CToTy)) { 7354 Qualifiers FromQs = CFromTy.getQualifiers(); 7355 Qualifiers ToQs = CToTy.getQualifiers(); 7356 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) { 7357 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_arc_conv) 7358 << (unsigned) FnKind << FnDesc 7359 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7360 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 7361 MaybeEmitInheritedConstructorNote(S, Fn); 7362 return; 7363 } 7364 } 7365 7366 // Emit the generic diagnostic and, optionally, add the hints to it. 7367 PartialDiagnostic FDiag = S.PDiag(diag::note_ovl_candidate_bad_conv); 7368 FDiag << (unsigned) FnKind << FnDesc 7369 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 7370 << FromTy << ToTy << (unsigned) isObjectArgument << I + 1 7371 << (unsigned) (Cand->Fix.Kind); 7372 7373 // If we can fix the conversion, suggest the FixIts. 7374 for (SmallVector<FixItHint, 1>::iterator 7375 HI = Cand->Fix.Hints.begin(), HE = Cand->Fix.Hints.end(); 7376 HI != HE; ++HI) 7377 FDiag << *HI; 7378 S.Diag(Fn->getLocation(), FDiag); 7379 7380 MaybeEmitInheritedConstructorNote(S, Fn); 7381} 7382 7383void DiagnoseArityMismatch(Sema &S, OverloadCandidate *Cand, 7384 unsigned NumFormalArgs) { 7385 // TODO: treat calls to a missing default constructor as a special case 7386 7387 FunctionDecl *Fn = Cand->Function; 7388 const FunctionProtoType *FnTy = Fn->getType()->getAs<FunctionProtoType>(); 7389 7390 unsigned MinParams = Fn->getMinRequiredArguments(); 7391 7392 // With invalid overloaded operators, it's possible that we think we 7393 // have an arity mismatch when it fact it looks like we have the 7394 // right number of arguments, because only overloaded operators have 7395 // the weird behavior of overloading member and non-member functions. 7396 // Just don't report anything. 7397 if (Fn->isInvalidDecl() && 7398 Fn->getDeclName().getNameKind() == DeclarationName::CXXOperatorName) 7399 return; 7400 7401 // at least / at most / exactly 7402 unsigned mode, modeCount; 7403 if (NumFormalArgs < MinParams) { 7404 assert((Cand->FailureKind == ovl_fail_too_few_arguments) || 7405 (Cand->FailureKind == ovl_fail_bad_deduction && 7406 Cand->DeductionFailure.Result == Sema::TDK_TooFewArguments)); 7407 if (MinParams != FnTy->getNumArgs() || 7408 FnTy->isVariadic() || FnTy->isTemplateVariadic()) 7409 mode = 0; // "at least" 7410 else 7411 mode = 2; // "exactly" 7412 modeCount = MinParams; 7413 } else { 7414 assert((Cand->FailureKind == ovl_fail_too_many_arguments) || 7415 (Cand->FailureKind == ovl_fail_bad_deduction && 7416 Cand->DeductionFailure.Result == Sema::TDK_TooManyArguments)); 7417 if (MinParams != FnTy->getNumArgs()) 7418 mode = 1; // "at most" 7419 else 7420 mode = 2; // "exactly" 7421 modeCount = FnTy->getNumArgs(); 7422 } 7423 7424 std::string Description; 7425 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, Description); 7426 7427 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity) 7428 << (unsigned) FnKind << (Fn->getDescribedFunctionTemplate() != 0) << mode 7429 << modeCount << NumFormalArgs; 7430 MaybeEmitInheritedConstructorNote(S, Fn); 7431} 7432 7433/// Diagnose a failed template-argument deduction. 7434void DiagnoseBadDeduction(Sema &S, OverloadCandidate *Cand, 7435 Expr **Args, unsigned NumArgs) { 7436 FunctionDecl *Fn = Cand->Function; // pattern 7437 7438 TemplateParameter Param = Cand->DeductionFailure.getTemplateParameter(); 7439 NamedDecl *ParamD; 7440 (ParamD = Param.dyn_cast<TemplateTypeParmDecl*>()) || 7441 (ParamD = Param.dyn_cast<NonTypeTemplateParmDecl*>()) || 7442 (ParamD = Param.dyn_cast<TemplateTemplateParmDecl*>()); 7443 switch (Cand->DeductionFailure.Result) { 7444 case Sema::TDK_Success: 7445 llvm_unreachable("TDK_success while diagnosing bad deduction"); 7446 7447 case Sema::TDK_Incomplete: { 7448 assert(ParamD && "no parameter found for incomplete deduction result"); 7449 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_incomplete_deduction) 7450 << ParamD->getDeclName(); 7451 MaybeEmitInheritedConstructorNote(S, Fn); 7452 return; 7453 } 7454 7455 case Sema::TDK_Underqualified: { 7456 assert(ParamD && "no parameter found for bad qualifiers deduction result"); 7457 TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD); 7458 7459 QualType Param = Cand->DeductionFailure.getFirstArg()->getAsType(); 7460 7461 // Param will have been canonicalized, but it should just be a 7462 // qualified version of ParamD, so move the qualifiers to that. 7463 QualifierCollector Qs; 7464 Qs.strip(Param); 7465 QualType NonCanonParam = Qs.apply(S.Context, TParam->getTypeForDecl()); 7466 assert(S.Context.hasSameType(Param, NonCanonParam)); 7467 7468 // Arg has also been canonicalized, but there's nothing we can do 7469 // about that. It also doesn't matter as much, because it won't 7470 // have any template parameters in it (because deduction isn't 7471 // done on dependent types). 7472 QualType Arg = Cand->DeductionFailure.getSecondArg()->getAsType(); 7473 7474 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_underqualified) 7475 << ParamD->getDeclName() << Arg << NonCanonParam; 7476 MaybeEmitInheritedConstructorNote(S, Fn); 7477 return; 7478 } 7479 7480 case Sema::TDK_Inconsistent: { 7481 assert(ParamD && "no parameter found for inconsistent deduction result"); 7482 int which = 0; 7483 if (isa<TemplateTypeParmDecl>(ParamD)) 7484 which = 0; 7485 else if (isa<NonTypeTemplateParmDecl>(ParamD)) 7486 which = 1; 7487 else { 7488 which = 2; 7489 } 7490 7491 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_inconsistent_deduction) 7492 << which << ParamD->getDeclName() 7493 << *Cand->DeductionFailure.getFirstArg() 7494 << *Cand->DeductionFailure.getSecondArg(); 7495 MaybeEmitInheritedConstructorNote(S, Fn); 7496 return; 7497 } 7498 7499 case Sema::TDK_InvalidExplicitArguments: 7500 assert(ParamD && "no parameter found for invalid explicit arguments"); 7501 if (ParamD->getDeclName()) 7502 S.Diag(Fn->getLocation(), 7503 diag::note_ovl_candidate_explicit_arg_mismatch_named) 7504 << ParamD->getDeclName(); 7505 else { 7506 int index = 0; 7507 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ParamD)) 7508 index = TTP->getIndex(); 7509 else if (NonTypeTemplateParmDecl *NTTP 7510 = dyn_cast<NonTypeTemplateParmDecl>(ParamD)) 7511 index = NTTP->getIndex(); 7512 else 7513 index = cast<TemplateTemplateParmDecl>(ParamD)->getIndex(); 7514 S.Diag(Fn->getLocation(), 7515 diag::note_ovl_candidate_explicit_arg_mismatch_unnamed) 7516 << (index + 1); 7517 } 7518 MaybeEmitInheritedConstructorNote(S, Fn); 7519 return; 7520 7521 case Sema::TDK_TooManyArguments: 7522 case Sema::TDK_TooFewArguments: 7523 DiagnoseArityMismatch(S, Cand, NumArgs); 7524 return; 7525 7526 case Sema::TDK_InstantiationDepth: 7527 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_instantiation_depth); 7528 MaybeEmitInheritedConstructorNote(S, Fn); 7529 return; 7530 7531 case Sema::TDK_SubstitutionFailure: { 7532 std::string ArgString; 7533 if (TemplateArgumentList *Args 7534 = Cand->DeductionFailure.getTemplateArgumentList()) 7535 ArgString = S.getTemplateArgumentBindingsText( 7536 Fn->getDescribedFunctionTemplate()->getTemplateParameters(), 7537 *Args); 7538 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_substitution_failure) 7539 << ArgString; 7540 MaybeEmitInheritedConstructorNote(S, Fn); 7541 return; 7542 } 7543 7544 // TODO: diagnose these individually, then kill off 7545 // note_ovl_candidate_bad_deduction, which is uselessly vague. 7546 case Sema::TDK_NonDeducedMismatch: 7547 case Sema::TDK_FailedOverloadResolution: 7548 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_deduction); 7549 MaybeEmitInheritedConstructorNote(S, Fn); 7550 return; 7551 } 7552} 7553 7554/// CUDA: diagnose an invalid call across targets. 7555void DiagnoseBadTarget(Sema &S, OverloadCandidate *Cand) { 7556 FunctionDecl *Caller = cast<FunctionDecl>(S.CurContext); 7557 FunctionDecl *Callee = Cand->Function; 7558 7559 Sema::CUDAFunctionTarget CallerTarget = S.IdentifyCUDATarget(Caller), 7560 CalleeTarget = S.IdentifyCUDATarget(Callee); 7561 7562 std::string FnDesc; 7563 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Callee, FnDesc); 7564 7565 S.Diag(Callee->getLocation(), diag::note_ovl_candidate_bad_target) 7566 << (unsigned) FnKind << CalleeTarget << CallerTarget; 7567} 7568 7569/// Generates a 'note' diagnostic for an overload candidate. We've 7570/// already generated a primary error at the call site. 7571/// 7572/// It really does need to be a single diagnostic with its caret 7573/// pointed at the candidate declaration. Yes, this creates some 7574/// major challenges of technical writing. Yes, this makes pointing 7575/// out problems with specific arguments quite awkward. It's still 7576/// better than generating twenty screens of text for every failed 7577/// overload. 7578/// 7579/// It would be great to be able to express per-candidate problems 7580/// more richly for those diagnostic clients that cared, but we'd 7581/// still have to be just as careful with the default diagnostics. 7582void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand, 7583 Expr **Args, unsigned NumArgs) { 7584 FunctionDecl *Fn = Cand->Function; 7585 7586 // Note deleted candidates, but only if they're viable. 7587 if (Cand->Viable && (Fn->isDeleted() || 7588 S.isFunctionConsideredUnavailable(Fn))) { 7589 std::string FnDesc; 7590 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 7591 7592 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_deleted) 7593 << FnKind << FnDesc << Fn->isDeleted(); 7594 MaybeEmitInheritedConstructorNote(S, Fn); 7595 return; 7596 } 7597 7598 // We don't really have anything else to say about viable candidates. 7599 if (Cand->Viable) { 7600 S.NoteOverloadCandidate(Fn); 7601 return; 7602 } 7603 7604 switch (Cand->FailureKind) { 7605 case ovl_fail_too_many_arguments: 7606 case ovl_fail_too_few_arguments: 7607 return DiagnoseArityMismatch(S, Cand, NumArgs); 7608 7609 case ovl_fail_bad_deduction: 7610 return DiagnoseBadDeduction(S, Cand, Args, NumArgs); 7611 7612 case ovl_fail_trivial_conversion: 7613 case ovl_fail_bad_final_conversion: 7614 case ovl_fail_final_conversion_not_exact: 7615 return S.NoteOverloadCandidate(Fn); 7616 7617 case ovl_fail_bad_conversion: { 7618 unsigned I = (Cand->IgnoreObjectArgument ? 1 : 0); 7619 for (unsigned N = Cand->Conversions.size(); I != N; ++I) 7620 if (Cand->Conversions[I].isBad()) 7621 return DiagnoseBadConversion(S, Cand, I); 7622 7623 // FIXME: this currently happens when we're called from SemaInit 7624 // when user-conversion overload fails. Figure out how to handle 7625 // those conditions and diagnose them well. 7626 return S.NoteOverloadCandidate(Fn); 7627 } 7628 7629 case ovl_fail_bad_target: 7630 return DiagnoseBadTarget(S, Cand); 7631 } 7632} 7633 7634void NoteSurrogateCandidate(Sema &S, OverloadCandidate *Cand) { 7635 // Desugar the type of the surrogate down to a function type, 7636 // retaining as many typedefs as possible while still showing 7637 // the function type (and, therefore, its parameter types). 7638 QualType FnType = Cand->Surrogate->getConversionType(); 7639 bool isLValueReference = false; 7640 bool isRValueReference = false; 7641 bool isPointer = false; 7642 if (const LValueReferenceType *FnTypeRef = 7643 FnType->getAs<LValueReferenceType>()) { 7644 FnType = FnTypeRef->getPointeeType(); 7645 isLValueReference = true; 7646 } else if (const RValueReferenceType *FnTypeRef = 7647 FnType->getAs<RValueReferenceType>()) { 7648 FnType = FnTypeRef->getPointeeType(); 7649 isRValueReference = true; 7650 } 7651 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) { 7652 FnType = FnTypePtr->getPointeeType(); 7653 isPointer = true; 7654 } 7655 // Desugar down to a function type. 7656 FnType = QualType(FnType->getAs<FunctionType>(), 0); 7657 // Reconstruct the pointer/reference as appropriate. 7658 if (isPointer) FnType = S.Context.getPointerType(FnType); 7659 if (isRValueReference) FnType = S.Context.getRValueReferenceType(FnType); 7660 if (isLValueReference) FnType = S.Context.getLValueReferenceType(FnType); 7661 7662 S.Diag(Cand->Surrogate->getLocation(), diag::note_ovl_surrogate_cand) 7663 << FnType; 7664 MaybeEmitInheritedConstructorNote(S, Cand->Surrogate); 7665} 7666 7667void NoteBuiltinOperatorCandidate(Sema &S, 7668 const char *Opc, 7669 SourceLocation OpLoc, 7670 OverloadCandidate *Cand) { 7671 assert(Cand->Conversions.size() <= 2 && "builtin operator is not binary"); 7672 std::string TypeStr("operator"); 7673 TypeStr += Opc; 7674 TypeStr += "("; 7675 TypeStr += Cand->BuiltinTypes.ParamTypes[0].getAsString(); 7676 if (Cand->Conversions.size() == 1) { 7677 TypeStr += ")"; 7678 S.Diag(OpLoc, diag::note_ovl_builtin_unary_candidate) << TypeStr; 7679 } else { 7680 TypeStr += ", "; 7681 TypeStr += Cand->BuiltinTypes.ParamTypes[1].getAsString(); 7682 TypeStr += ")"; 7683 S.Diag(OpLoc, diag::note_ovl_builtin_binary_candidate) << TypeStr; 7684 } 7685} 7686 7687void NoteAmbiguousUserConversions(Sema &S, SourceLocation OpLoc, 7688 OverloadCandidate *Cand) { 7689 unsigned NoOperands = Cand->Conversions.size(); 7690 for (unsigned ArgIdx = 0; ArgIdx < NoOperands; ++ArgIdx) { 7691 const ImplicitConversionSequence &ICS = Cand->Conversions[ArgIdx]; 7692 if (ICS.isBad()) break; // all meaningless after first invalid 7693 if (!ICS.isAmbiguous()) continue; 7694 7695 ICS.DiagnoseAmbiguousConversion(S, OpLoc, 7696 S.PDiag(diag::note_ambiguous_type_conversion)); 7697 } 7698} 7699 7700SourceLocation GetLocationForCandidate(const OverloadCandidate *Cand) { 7701 if (Cand->Function) 7702 return Cand->Function->getLocation(); 7703 if (Cand->IsSurrogate) 7704 return Cand->Surrogate->getLocation(); 7705 return SourceLocation(); 7706} 7707 7708static unsigned 7709RankDeductionFailure(const OverloadCandidate::DeductionFailureInfo &DFI) { 7710 switch ((Sema::TemplateDeductionResult)DFI.Result) { 7711 case Sema::TDK_Success: 7712 llvm_unreachable("TDK_success while diagnosing bad deduction"); 7713 7714 case Sema::TDK_Incomplete: 7715 return 1; 7716 7717 case Sema::TDK_Underqualified: 7718 case Sema::TDK_Inconsistent: 7719 return 2; 7720 7721 case Sema::TDK_SubstitutionFailure: 7722 case Sema::TDK_NonDeducedMismatch: 7723 return 3; 7724 7725 case Sema::TDK_InstantiationDepth: 7726 case Sema::TDK_FailedOverloadResolution: 7727 return 4; 7728 7729 case Sema::TDK_InvalidExplicitArguments: 7730 return 5; 7731 7732 case Sema::TDK_TooManyArguments: 7733 case Sema::TDK_TooFewArguments: 7734 return 6; 7735 } 7736 llvm_unreachable("Unhandled deduction result"); 7737} 7738 7739struct CompareOverloadCandidatesForDisplay { 7740 Sema &S; 7741 CompareOverloadCandidatesForDisplay(Sema &S) : S(S) {} 7742 7743 bool operator()(const OverloadCandidate *L, 7744 const OverloadCandidate *R) { 7745 // Fast-path this check. 7746 if (L == R) return false; 7747 7748 // Order first by viability. 7749 if (L->Viable) { 7750 if (!R->Viable) return true; 7751 7752 // TODO: introduce a tri-valued comparison for overload 7753 // candidates. Would be more worthwhile if we had a sort 7754 // that could exploit it. 7755 if (isBetterOverloadCandidate(S, *L, *R, SourceLocation())) return true; 7756 if (isBetterOverloadCandidate(S, *R, *L, SourceLocation())) return false; 7757 } else if (R->Viable) 7758 return false; 7759 7760 assert(L->Viable == R->Viable); 7761 7762 // Criteria by which we can sort non-viable candidates: 7763 if (!L->Viable) { 7764 // 1. Arity mismatches come after other candidates. 7765 if (L->FailureKind == ovl_fail_too_many_arguments || 7766 L->FailureKind == ovl_fail_too_few_arguments) 7767 return false; 7768 if (R->FailureKind == ovl_fail_too_many_arguments || 7769 R->FailureKind == ovl_fail_too_few_arguments) 7770 return true; 7771 7772 // 2. Bad conversions come first and are ordered by the number 7773 // of bad conversions and quality of good conversions. 7774 if (L->FailureKind == ovl_fail_bad_conversion) { 7775 if (R->FailureKind != ovl_fail_bad_conversion) 7776 return true; 7777 7778 // The conversion that can be fixed with a smaller number of changes, 7779 // comes first. 7780 unsigned numLFixes = L->Fix.NumConversionsFixed; 7781 unsigned numRFixes = R->Fix.NumConversionsFixed; 7782 numLFixes = (numLFixes == 0) ? UINT_MAX : numLFixes; 7783 numRFixes = (numRFixes == 0) ? UINT_MAX : numRFixes; 7784 if (numLFixes != numRFixes) { 7785 if (numLFixes < numRFixes) 7786 return true; 7787 else 7788 return false; 7789 } 7790 7791 // If there's any ordering between the defined conversions... 7792 // FIXME: this might not be transitive. 7793 assert(L->Conversions.size() == R->Conversions.size()); 7794 7795 int leftBetter = 0; 7796 unsigned I = (L->IgnoreObjectArgument || R->IgnoreObjectArgument); 7797 for (unsigned E = L->Conversions.size(); I != E; ++I) { 7798 switch (CompareImplicitConversionSequences(S, 7799 L->Conversions[I], 7800 R->Conversions[I])) { 7801 case ImplicitConversionSequence::Better: 7802 leftBetter++; 7803 break; 7804 7805 case ImplicitConversionSequence::Worse: 7806 leftBetter--; 7807 break; 7808 7809 case ImplicitConversionSequence::Indistinguishable: 7810 break; 7811 } 7812 } 7813 if (leftBetter > 0) return true; 7814 if (leftBetter < 0) return false; 7815 7816 } else if (R->FailureKind == ovl_fail_bad_conversion) 7817 return false; 7818 7819 if (L->FailureKind == ovl_fail_bad_deduction) { 7820 if (R->FailureKind != ovl_fail_bad_deduction) 7821 return true; 7822 7823 if (L->DeductionFailure.Result != R->DeductionFailure.Result) 7824 return RankDeductionFailure(L->DeductionFailure) 7825 < RankDeductionFailure(R->DeductionFailure); 7826 } else if (R->FailureKind == ovl_fail_bad_deduction) 7827 return false; 7828 7829 // TODO: others? 7830 } 7831 7832 // Sort everything else by location. 7833 SourceLocation LLoc = GetLocationForCandidate(L); 7834 SourceLocation RLoc = GetLocationForCandidate(R); 7835 7836 // Put candidates without locations (e.g. builtins) at the end. 7837 if (LLoc.isInvalid()) return false; 7838 if (RLoc.isInvalid()) return true; 7839 7840 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc); 7841 } 7842}; 7843 7844/// CompleteNonViableCandidate - Normally, overload resolution only 7845/// computes up to the first. Produces the FixIt set if possible. 7846void CompleteNonViableCandidate(Sema &S, OverloadCandidate *Cand, 7847 Expr **Args, unsigned NumArgs) { 7848 assert(!Cand->Viable); 7849 7850 // Don't do anything on failures other than bad conversion. 7851 if (Cand->FailureKind != ovl_fail_bad_conversion) return; 7852 7853 // We only want the FixIts if all the arguments can be corrected. 7854 bool Unfixable = false; 7855 // Use a implicit copy initialization to check conversion fixes. 7856 Cand->Fix.setConversionChecker(TryCopyInitialization); 7857 7858 // Skip forward to the first bad conversion. 7859 unsigned ConvIdx = (Cand->IgnoreObjectArgument ? 1 : 0); 7860 unsigned ConvCount = Cand->Conversions.size(); 7861 while (true) { 7862 assert(ConvIdx != ConvCount && "no bad conversion in candidate"); 7863 ConvIdx++; 7864 if (Cand->Conversions[ConvIdx - 1].isBad()) { 7865 Unfixable = !Cand->TryToFixBadConversion(ConvIdx - 1, S); 7866 break; 7867 } 7868 } 7869 7870 if (ConvIdx == ConvCount) 7871 return; 7872 7873 assert(!Cand->Conversions[ConvIdx].isInitialized() && 7874 "remaining conversion is initialized?"); 7875 7876 // FIXME: this should probably be preserved from the overload 7877 // operation somehow. 7878 bool SuppressUserConversions = false; 7879 7880 const FunctionProtoType* Proto; 7881 unsigned ArgIdx = ConvIdx; 7882 7883 if (Cand->IsSurrogate) { 7884 QualType ConvType 7885 = Cand->Surrogate->getConversionType().getNonReferenceType(); 7886 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 7887 ConvType = ConvPtrType->getPointeeType(); 7888 Proto = ConvType->getAs<FunctionProtoType>(); 7889 ArgIdx--; 7890 } else if (Cand->Function) { 7891 Proto = Cand->Function->getType()->getAs<FunctionProtoType>(); 7892 if (isa<CXXMethodDecl>(Cand->Function) && 7893 !isa<CXXConstructorDecl>(Cand->Function)) 7894 ArgIdx--; 7895 } else { 7896 // Builtin binary operator with a bad first conversion. 7897 assert(ConvCount <= 3); 7898 for (; ConvIdx != ConvCount; ++ConvIdx) 7899 Cand->Conversions[ConvIdx] 7900 = TryCopyInitialization(S, Args[ConvIdx], 7901 Cand->BuiltinTypes.ParamTypes[ConvIdx], 7902 SuppressUserConversions, 7903 /*InOverloadResolution*/ true, 7904 /*AllowObjCWritebackConversion=*/ 7905 S.getLangOptions().ObjCAutoRefCount); 7906 return; 7907 } 7908 7909 // Fill in the rest of the conversions. 7910 unsigned NumArgsInProto = Proto->getNumArgs(); 7911 for (; ConvIdx != ConvCount; ++ConvIdx, ++ArgIdx) { 7912 if (ArgIdx < NumArgsInProto) { 7913 Cand->Conversions[ConvIdx] 7914 = TryCopyInitialization(S, Args[ArgIdx], Proto->getArgType(ArgIdx), 7915 SuppressUserConversions, 7916 /*InOverloadResolution=*/true, 7917 /*AllowObjCWritebackConversion=*/ 7918 S.getLangOptions().ObjCAutoRefCount); 7919 // Store the FixIt in the candidate if it exists. 7920 if (!Unfixable && Cand->Conversions[ConvIdx].isBad()) 7921 Unfixable = !Cand->TryToFixBadConversion(ConvIdx, S); 7922 } 7923 else 7924 Cand->Conversions[ConvIdx].setEllipsis(); 7925 } 7926} 7927 7928} // end anonymous namespace 7929 7930/// PrintOverloadCandidates - When overload resolution fails, prints 7931/// diagnostic messages containing the candidates in the candidate 7932/// set. 7933void OverloadCandidateSet::NoteCandidates(Sema &S, 7934 OverloadCandidateDisplayKind OCD, 7935 Expr **Args, unsigned NumArgs, 7936 const char *Opc, 7937 SourceLocation OpLoc) { 7938 // Sort the candidates by viability and position. Sorting directly would 7939 // be prohibitive, so we make a set of pointers and sort those. 7940 SmallVector<OverloadCandidate*, 32> Cands; 7941 if (OCD == OCD_AllCandidates) Cands.reserve(size()); 7942 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) { 7943 if (Cand->Viable) 7944 Cands.push_back(Cand); 7945 else if (OCD == OCD_AllCandidates) { 7946 CompleteNonViableCandidate(S, Cand, Args, NumArgs); 7947 if (Cand->Function || Cand->IsSurrogate) 7948 Cands.push_back(Cand); 7949 // Otherwise, this a non-viable builtin candidate. We do not, in general, 7950 // want to list every possible builtin candidate. 7951 } 7952 } 7953 7954 std::sort(Cands.begin(), Cands.end(), 7955 CompareOverloadCandidatesForDisplay(S)); 7956 7957 bool ReportedAmbiguousConversions = false; 7958 7959 SmallVectorImpl<OverloadCandidate*>::iterator I, E; 7960 const DiagnosticsEngine::OverloadsShown ShowOverloads = 7961 S.Diags.getShowOverloads(); 7962 unsigned CandsShown = 0; 7963 for (I = Cands.begin(), E = Cands.end(); I != E; ++I) { 7964 OverloadCandidate *Cand = *I; 7965 7966 // Set an arbitrary limit on the number of candidate functions we'll spam 7967 // the user with. FIXME: This limit should depend on details of the 7968 // candidate list. 7969 if (CandsShown >= 4 && ShowOverloads == DiagnosticsEngine::Ovl_Best) { 7970 break; 7971 } 7972 ++CandsShown; 7973 7974 if (Cand->Function) 7975 NoteFunctionCandidate(S, Cand, Args, NumArgs); 7976 else if (Cand->IsSurrogate) 7977 NoteSurrogateCandidate(S, Cand); 7978 else { 7979 assert(Cand->Viable && 7980 "Non-viable built-in candidates are not added to Cands."); 7981 // Generally we only see ambiguities including viable builtin 7982 // operators if overload resolution got screwed up by an 7983 // ambiguous user-defined conversion. 7984 // 7985 // FIXME: It's quite possible for different conversions to see 7986 // different ambiguities, though. 7987 if (!ReportedAmbiguousConversions) { 7988 NoteAmbiguousUserConversions(S, OpLoc, Cand); 7989 ReportedAmbiguousConversions = true; 7990 } 7991 7992 // If this is a viable builtin, print it. 7993 NoteBuiltinOperatorCandidate(S, Opc, OpLoc, Cand); 7994 } 7995 } 7996 7997 if (I != E) 7998 S.Diag(OpLoc, diag::note_ovl_too_many_candidates) << int(E - I); 7999} 8000 8001// [PossiblyAFunctionType] --> [Return] 8002// NonFunctionType --> NonFunctionType 8003// R (A) --> R(A) 8004// R (*)(A) --> R (A) 8005// R (&)(A) --> R (A) 8006// R (S::*)(A) --> R (A) 8007QualType Sema::ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType) { 8008 QualType Ret = PossiblyAFunctionType; 8009 if (const PointerType *ToTypePtr = 8010 PossiblyAFunctionType->getAs<PointerType>()) 8011 Ret = ToTypePtr->getPointeeType(); 8012 else if (const ReferenceType *ToTypeRef = 8013 PossiblyAFunctionType->getAs<ReferenceType>()) 8014 Ret = ToTypeRef->getPointeeType(); 8015 else if (const MemberPointerType *MemTypePtr = 8016 PossiblyAFunctionType->getAs<MemberPointerType>()) 8017 Ret = MemTypePtr->getPointeeType(); 8018 Ret = 8019 Context.getCanonicalType(Ret).getUnqualifiedType(); 8020 return Ret; 8021} 8022 8023// A helper class to help with address of function resolution 8024// - allows us to avoid passing around all those ugly parameters 8025class AddressOfFunctionResolver 8026{ 8027 Sema& S; 8028 Expr* SourceExpr; 8029 const QualType& TargetType; 8030 QualType TargetFunctionType; // Extracted function type from target type 8031 8032 bool Complain; 8033 //DeclAccessPair& ResultFunctionAccessPair; 8034 ASTContext& Context; 8035 8036 bool TargetTypeIsNonStaticMemberFunction; 8037 bool FoundNonTemplateFunction; 8038 8039 OverloadExpr::FindResult OvlExprInfo; 8040 OverloadExpr *OvlExpr; 8041 TemplateArgumentListInfo OvlExplicitTemplateArgs; 8042 SmallVector<std::pair<DeclAccessPair, FunctionDecl*>, 4> Matches; 8043 8044public: 8045 AddressOfFunctionResolver(Sema &S, Expr* SourceExpr, 8046 const QualType& TargetType, bool Complain) 8047 : S(S), SourceExpr(SourceExpr), TargetType(TargetType), 8048 Complain(Complain), Context(S.getASTContext()), 8049 TargetTypeIsNonStaticMemberFunction( 8050 !!TargetType->getAs<MemberPointerType>()), 8051 FoundNonTemplateFunction(false), 8052 OvlExprInfo(OverloadExpr::find(SourceExpr)), 8053 OvlExpr(OvlExprInfo.Expression) 8054 { 8055 ExtractUnqualifiedFunctionTypeFromTargetType(); 8056 8057 if (!TargetFunctionType->isFunctionType()) { 8058 if (OvlExpr->hasExplicitTemplateArgs()) { 8059 DeclAccessPair dap; 8060 if (FunctionDecl* Fn = S.ResolveSingleFunctionTemplateSpecialization( 8061 OvlExpr, false, &dap) ) { 8062 8063 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 8064 if (!Method->isStatic()) { 8065 // If the target type is a non-function type and the function 8066 // found is a non-static member function, pretend as if that was 8067 // the target, it's the only possible type to end up with. 8068 TargetTypeIsNonStaticMemberFunction = true; 8069 8070 // And skip adding the function if its not in the proper form. 8071 // We'll diagnose this due to an empty set of functions. 8072 if (!OvlExprInfo.HasFormOfMemberPointer) 8073 return; 8074 } 8075 } 8076 8077 Matches.push_back(std::make_pair(dap,Fn)); 8078 } 8079 } 8080 return; 8081 } 8082 8083 if (OvlExpr->hasExplicitTemplateArgs()) 8084 OvlExpr->getExplicitTemplateArgs().copyInto(OvlExplicitTemplateArgs); 8085 8086 if (FindAllFunctionsThatMatchTargetTypeExactly()) { 8087 // C++ [over.over]p4: 8088 // If more than one function is selected, [...] 8089 if (Matches.size() > 1) { 8090 if (FoundNonTemplateFunction) 8091 EliminateAllTemplateMatches(); 8092 else 8093 EliminateAllExceptMostSpecializedTemplate(); 8094 } 8095 } 8096 } 8097 8098private: 8099 bool isTargetTypeAFunction() const { 8100 return TargetFunctionType->isFunctionType(); 8101 } 8102 8103 // [ToType] [Return] 8104 8105 // R (*)(A) --> R (A), IsNonStaticMemberFunction = false 8106 // R (&)(A) --> R (A), IsNonStaticMemberFunction = false 8107 // R (S::*)(A) --> R (A), IsNonStaticMemberFunction = true 8108 void inline ExtractUnqualifiedFunctionTypeFromTargetType() { 8109 TargetFunctionType = S.ExtractUnqualifiedFunctionType(TargetType); 8110 } 8111 8112 // return true if any matching specializations were found 8113 bool AddMatchingTemplateFunction(FunctionTemplateDecl* FunctionTemplate, 8114 const DeclAccessPair& CurAccessFunPair) { 8115 if (CXXMethodDecl *Method 8116 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) { 8117 // Skip non-static function templates when converting to pointer, and 8118 // static when converting to member pointer. 8119 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 8120 return false; 8121 } 8122 else if (TargetTypeIsNonStaticMemberFunction) 8123 return false; 8124 8125 // C++ [over.over]p2: 8126 // If the name is a function template, template argument deduction is 8127 // done (14.8.2.2), and if the argument deduction succeeds, the 8128 // resulting template argument list is used to generate a single 8129 // function template specialization, which is added to the set of 8130 // overloaded functions considered. 8131 FunctionDecl *Specialization = 0; 8132 TemplateDeductionInfo Info(Context, OvlExpr->getNameLoc()); 8133 if (Sema::TemplateDeductionResult Result 8134 = S.DeduceTemplateArguments(FunctionTemplate, 8135 &OvlExplicitTemplateArgs, 8136 TargetFunctionType, Specialization, 8137 Info)) { 8138 // FIXME: make a note of the failed deduction for diagnostics. 8139 (void)Result; 8140 return false; 8141 } 8142 8143 // Template argument deduction ensures that we have an exact match. 8144 // This function template specicalization works. 8145 Specialization = cast<FunctionDecl>(Specialization->getCanonicalDecl()); 8146 assert(TargetFunctionType 8147 == Context.getCanonicalType(Specialization->getType())); 8148 Matches.push_back(std::make_pair(CurAccessFunPair, Specialization)); 8149 return true; 8150 } 8151 8152 bool AddMatchingNonTemplateFunction(NamedDecl* Fn, 8153 const DeclAccessPair& CurAccessFunPair) { 8154 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 8155 // Skip non-static functions when converting to pointer, and static 8156 // when converting to member pointer. 8157 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 8158 return false; 8159 } 8160 else if (TargetTypeIsNonStaticMemberFunction) 8161 return false; 8162 8163 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) { 8164 if (S.getLangOptions().CUDA) 8165 if (FunctionDecl *Caller = dyn_cast<FunctionDecl>(S.CurContext)) 8166 if (S.CheckCUDATarget(Caller, FunDecl)) 8167 return false; 8168 8169 QualType ResultTy; 8170 if (Context.hasSameUnqualifiedType(TargetFunctionType, 8171 FunDecl->getType()) || 8172 S.IsNoReturnConversion(FunDecl->getType(), TargetFunctionType, 8173 ResultTy)) { 8174 Matches.push_back(std::make_pair(CurAccessFunPair, 8175 cast<FunctionDecl>(FunDecl->getCanonicalDecl()))); 8176 FoundNonTemplateFunction = true; 8177 return true; 8178 } 8179 } 8180 8181 return false; 8182 } 8183 8184 bool FindAllFunctionsThatMatchTargetTypeExactly() { 8185 bool Ret = false; 8186 8187 // If the overload expression doesn't have the form of a pointer to 8188 // member, don't try to convert it to a pointer-to-member type. 8189 if (IsInvalidFormOfPointerToMemberFunction()) 8190 return false; 8191 8192 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 8193 E = OvlExpr->decls_end(); 8194 I != E; ++I) { 8195 // Look through any using declarations to find the underlying function. 8196 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 8197 8198 // C++ [over.over]p3: 8199 // Non-member functions and static member functions match 8200 // targets of type "pointer-to-function" or "reference-to-function." 8201 // Nonstatic member functions match targets of 8202 // type "pointer-to-member-function." 8203 // Note that according to DR 247, the containing class does not matter. 8204 if (FunctionTemplateDecl *FunctionTemplate 8205 = dyn_cast<FunctionTemplateDecl>(Fn)) { 8206 if (AddMatchingTemplateFunction(FunctionTemplate, I.getPair())) 8207 Ret = true; 8208 } 8209 // If we have explicit template arguments supplied, skip non-templates. 8210 else if (!OvlExpr->hasExplicitTemplateArgs() && 8211 AddMatchingNonTemplateFunction(Fn, I.getPair())) 8212 Ret = true; 8213 } 8214 assert(Ret || Matches.empty()); 8215 return Ret; 8216 } 8217 8218 void EliminateAllExceptMostSpecializedTemplate() { 8219 // [...] and any given function template specialization F1 is 8220 // eliminated if the set contains a second function template 8221 // specialization whose function template is more specialized 8222 // than the function template of F1 according to the partial 8223 // ordering rules of 14.5.5.2. 8224 8225 // The algorithm specified above is quadratic. We instead use a 8226 // two-pass algorithm (similar to the one used to identify the 8227 // best viable function in an overload set) that identifies the 8228 // best function template (if it exists). 8229 8230 UnresolvedSet<4> MatchesCopy; // TODO: avoid! 8231 for (unsigned I = 0, E = Matches.size(); I != E; ++I) 8232 MatchesCopy.addDecl(Matches[I].second, Matches[I].first.getAccess()); 8233 8234 UnresolvedSetIterator Result = 8235 S.getMostSpecialized(MatchesCopy.begin(), MatchesCopy.end(), 8236 TPOC_Other, 0, SourceExpr->getLocStart(), 8237 S.PDiag(), 8238 S.PDiag(diag::err_addr_ovl_ambiguous) 8239 << Matches[0].second->getDeclName(), 8240 S.PDiag(diag::note_ovl_candidate) 8241 << (unsigned) oc_function_template, 8242 Complain, TargetFunctionType); 8243 8244 if (Result != MatchesCopy.end()) { 8245 // Make it the first and only element 8246 Matches[0].first = Matches[Result - MatchesCopy.begin()].first; 8247 Matches[0].second = cast<FunctionDecl>(*Result); 8248 Matches.resize(1); 8249 } 8250 } 8251 8252 void EliminateAllTemplateMatches() { 8253 // [...] any function template specializations in the set are 8254 // eliminated if the set also contains a non-template function, [...] 8255 for (unsigned I = 0, N = Matches.size(); I != N; ) { 8256 if (Matches[I].second->getPrimaryTemplate() == 0) 8257 ++I; 8258 else { 8259 Matches[I] = Matches[--N]; 8260 Matches.set_size(N); 8261 } 8262 } 8263 } 8264 8265public: 8266 void ComplainNoMatchesFound() const { 8267 assert(Matches.empty()); 8268 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_no_viable) 8269 << OvlExpr->getName() << TargetFunctionType 8270 << OvlExpr->getSourceRange(); 8271 S.NoteAllOverloadCandidates(OvlExpr, TargetFunctionType); 8272 } 8273 8274 bool IsInvalidFormOfPointerToMemberFunction() const { 8275 return TargetTypeIsNonStaticMemberFunction && 8276 !OvlExprInfo.HasFormOfMemberPointer; 8277 } 8278 8279 void ComplainIsInvalidFormOfPointerToMemberFunction() const { 8280 // TODO: Should we condition this on whether any functions might 8281 // have matched, or is it more appropriate to do that in callers? 8282 // TODO: a fixit wouldn't hurt. 8283 S.Diag(OvlExpr->getNameLoc(), diag::err_addr_ovl_no_qualifier) 8284 << TargetType << OvlExpr->getSourceRange(); 8285 } 8286 8287 void ComplainOfInvalidConversion() const { 8288 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_not_func_ptrref) 8289 << OvlExpr->getName() << TargetType; 8290 } 8291 8292 void ComplainMultipleMatchesFound() const { 8293 assert(Matches.size() > 1); 8294 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_ambiguous) 8295 << OvlExpr->getName() 8296 << OvlExpr->getSourceRange(); 8297 S.NoteAllOverloadCandidates(OvlExpr, TargetFunctionType); 8298 } 8299 8300 bool hadMultipleCandidates() const { return (OvlExpr->getNumDecls() > 1); } 8301 8302 int getNumMatches() const { return Matches.size(); } 8303 8304 FunctionDecl* getMatchingFunctionDecl() const { 8305 if (Matches.size() != 1) return 0; 8306 return Matches[0].second; 8307 } 8308 8309 const DeclAccessPair* getMatchingFunctionAccessPair() const { 8310 if (Matches.size() != 1) return 0; 8311 return &Matches[0].first; 8312 } 8313}; 8314 8315/// ResolveAddressOfOverloadedFunction - Try to resolve the address of 8316/// an overloaded function (C++ [over.over]), where @p From is an 8317/// expression with overloaded function type and @p ToType is the type 8318/// we're trying to resolve to. For example: 8319/// 8320/// @code 8321/// int f(double); 8322/// int f(int); 8323/// 8324/// int (*pfd)(double) = f; // selects f(double) 8325/// @endcode 8326/// 8327/// This routine returns the resulting FunctionDecl if it could be 8328/// resolved, and NULL otherwise. When @p Complain is true, this 8329/// routine will emit diagnostics if there is an error. 8330FunctionDecl * 8331Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr, 8332 QualType TargetType, 8333 bool Complain, 8334 DeclAccessPair &FoundResult, 8335 bool *pHadMultipleCandidates) { 8336 assert(AddressOfExpr->getType() == Context.OverloadTy); 8337 8338 AddressOfFunctionResolver Resolver(*this, AddressOfExpr, TargetType, 8339 Complain); 8340 int NumMatches = Resolver.getNumMatches(); 8341 FunctionDecl* Fn = 0; 8342 if (NumMatches == 0 && Complain) { 8343 if (Resolver.IsInvalidFormOfPointerToMemberFunction()) 8344 Resolver.ComplainIsInvalidFormOfPointerToMemberFunction(); 8345 else 8346 Resolver.ComplainNoMatchesFound(); 8347 } 8348 else if (NumMatches > 1 && Complain) 8349 Resolver.ComplainMultipleMatchesFound(); 8350 else if (NumMatches == 1) { 8351 Fn = Resolver.getMatchingFunctionDecl(); 8352 assert(Fn); 8353 FoundResult = *Resolver.getMatchingFunctionAccessPair(); 8354 MarkDeclarationReferenced(AddressOfExpr->getLocStart(), Fn); 8355 if (Complain) 8356 CheckAddressOfMemberAccess(AddressOfExpr, FoundResult); 8357 } 8358 8359 if (pHadMultipleCandidates) 8360 *pHadMultipleCandidates = Resolver.hadMultipleCandidates(); 8361 return Fn; 8362} 8363 8364/// \brief Given an expression that refers to an overloaded function, try to 8365/// resolve that overloaded function expression down to a single function. 8366/// 8367/// This routine can only resolve template-ids that refer to a single function 8368/// template, where that template-id refers to a single template whose template 8369/// arguments are either provided by the template-id or have defaults, 8370/// as described in C++0x [temp.arg.explicit]p3. 8371FunctionDecl * 8372Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, 8373 bool Complain, 8374 DeclAccessPair *FoundResult) { 8375 // C++ [over.over]p1: 8376 // [...] [Note: any redundant set of parentheses surrounding the 8377 // overloaded function name is ignored (5.1). ] 8378 // C++ [over.over]p1: 8379 // [...] The overloaded function name can be preceded by the & 8380 // operator. 8381 8382 // If we didn't actually find any template-ids, we're done. 8383 if (!ovl->hasExplicitTemplateArgs()) 8384 return 0; 8385 8386 TemplateArgumentListInfo ExplicitTemplateArgs; 8387 ovl->getExplicitTemplateArgs().copyInto(ExplicitTemplateArgs); 8388 8389 // Look through all of the overloaded functions, searching for one 8390 // whose type matches exactly. 8391 FunctionDecl *Matched = 0; 8392 for (UnresolvedSetIterator I = ovl->decls_begin(), 8393 E = ovl->decls_end(); I != E; ++I) { 8394 // C++0x [temp.arg.explicit]p3: 8395 // [...] In contexts where deduction is done and fails, or in contexts 8396 // where deduction is not done, if a template argument list is 8397 // specified and it, along with any default template arguments, 8398 // identifies a single function template specialization, then the 8399 // template-id is an lvalue for the function template specialization. 8400 FunctionTemplateDecl *FunctionTemplate 8401 = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()); 8402 8403 // C++ [over.over]p2: 8404 // If the name is a function template, template argument deduction is 8405 // done (14.8.2.2), and if the argument deduction succeeds, the 8406 // resulting template argument list is used to generate a single 8407 // function template specialization, which is added to the set of 8408 // overloaded functions considered. 8409 FunctionDecl *Specialization = 0; 8410 TemplateDeductionInfo Info(Context, ovl->getNameLoc()); 8411 if (TemplateDeductionResult Result 8412 = DeduceTemplateArguments(FunctionTemplate, &ExplicitTemplateArgs, 8413 Specialization, Info)) { 8414 // FIXME: make a note of the failed deduction for diagnostics. 8415 (void)Result; 8416 continue; 8417 } 8418 8419 assert(Specialization && "no specialization and no error?"); 8420 8421 // Multiple matches; we can't resolve to a single declaration. 8422 if (Matched) { 8423 if (Complain) { 8424 Diag(ovl->getExprLoc(), diag::err_addr_ovl_ambiguous) 8425 << ovl->getName(); 8426 NoteAllOverloadCandidates(ovl); 8427 } 8428 return 0; 8429 } 8430 8431 Matched = Specialization; 8432 if (FoundResult) *FoundResult = I.getPair(); 8433 } 8434 8435 return Matched; 8436} 8437 8438 8439 8440 8441// Resolve and fix an overloaded expression that can be resolved 8442// because it identifies a single function template specialization. 8443// 8444// Last three arguments should only be supplied if Complain = true 8445// 8446// Return true if it was logically possible to so resolve the 8447// expression, regardless of whether or not it succeeded. Always 8448// returns true if 'complain' is set. 8449bool Sema::ResolveAndFixSingleFunctionTemplateSpecialization( 8450 ExprResult &SrcExpr, bool doFunctionPointerConverion, 8451 bool complain, const SourceRange& OpRangeForComplaining, 8452 QualType DestTypeForComplaining, 8453 unsigned DiagIDForComplaining) { 8454 assert(SrcExpr.get()->getType() == Context.OverloadTy); 8455 8456 OverloadExpr::FindResult ovl = OverloadExpr::find(SrcExpr.get()); 8457 8458 DeclAccessPair found; 8459 ExprResult SingleFunctionExpression; 8460 if (FunctionDecl *fn = ResolveSingleFunctionTemplateSpecialization( 8461 ovl.Expression, /*complain*/ false, &found)) { 8462 if (DiagnoseUseOfDecl(fn, SrcExpr.get()->getSourceRange().getBegin())) { 8463 SrcExpr = ExprError(); 8464 return true; 8465 } 8466 8467 // It is only correct to resolve to an instance method if we're 8468 // resolving a form that's permitted to be a pointer to member. 8469 // Otherwise we'll end up making a bound member expression, which 8470 // is illegal in all the contexts we resolve like this. 8471 if (!ovl.HasFormOfMemberPointer && 8472 isa<CXXMethodDecl>(fn) && 8473 cast<CXXMethodDecl>(fn)->isInstance()) { 8474 if (!complain) return false; 8475 8476 Diag(ovl.Expression->getExprLoc(), 8477 diag::err_bound_member_function) 8478 << 0 << ovl.Expression->getSourceRange(); 8479 8480 // TODO: I believe we only end up here if there's a mix of 8481 // static and non-static candidates (otherwise the expression 8482 // would have 'bound member' type, not 'overload' type). 8483 // Ideally we would note which candidate was chosen and why 8484 // the static candidates were rejected. 8485 SrcExpr = ExprError(); 8486 return true; 8487 } 8488 8489 // Fix the expresion to refer to 'fn'. 8490 SingleFunctionExpression = 8491 Owned(FixOverloadedFunctionReference(SrcExpr.take(), found, fn)); 8492 8493 // If desired, do function-to-pointer decay. 8494 if (doFunctionPointerConverion) { 8495 SingleFunctionExpression = 8496 DefaultFunctionArrayLvalueConversion(SingleFunctionExpression.take()); 8497 if (SingleFunctionExpression.isInvalid()) { 8498 SrcExpr = ExprError(); 8499 return true; 8500 } 8501 } 8502 } 8503 8504 if (!SingleFunctionExpression.isUsable()) { 8505 if (complain) { 8506 Diag(OpRangeForComplaining.getBegin(), DiagIDForComplaining) 8507 << ovl.Expression->getName() 8508 << DestTypeForComplaining 8509 << OpRangeForComplaining 8510 << ovl.Expression->getQualifierLoc().getSourceRange(); 8511 NoteAllOverloadCandidates(SrcExpr.get()); 8512 8513 SrcExpr = ExprError(); 8514 return true; 8515 } 8516 8517 return false; 8518 } 8519 8520 SrcExpr = SingleFunctionExpression; 8521 return true; 8522} 8523 8524/// \brief Add a single candidate to the overload set. 8525static void AddOverloadedCallCandidate(Sema &S, 8526 DeclAccessPair FoundDecl, 8527 TemplateArgumentListInfo *ExplicitTemplateArgs, 8528 Expr **Args, unsigned NumArgs, 8529 OverloadCandidateSet &CandidateSet, 8530 bool PartialOverloading, 8531 bool KnownValid) { 8532 NamedDecl *Callee = FoundDecl.getDecl(); 8533 if (isa<UsingShadowDecl>(Callee)) 8534 Callee = cast<UsingShadowDecl>(Callee)->getTargetDecl(); 8535 8536 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) { 8537 if (ExplicitTemplateArgs) { 8538 assert(!KnownValid && "Explicit template arguments?"); 8539 return; 8540 } 8541 S.AddOverloadCandidate(Func, FoundDecl, Args, NumArgs, CandidateSet, 8542 false, PartialOverloading); 8543 return; 8544 } 8545 8546 if (FunctionTemplateDecl *FuncTemplate 8547 = dyn_cast<FunctionTemplateDecl>(Callee)) { 8548 S.AddTemplateOverloadCandidate(FuncTemplate, FoundDecl, 8549 ExplicitTemplateArgs, 8550 Args, NumArgs, CandidateSet); 8551 return; 8552 } 8553 8554 assert(!KnownValid && "unhandled case in overloaded call candidate"); 8555} 8556 8557/// \brief Add the overload candidates named by callee and/or found by argument 8558/// dependent lookup to the given overload set. 8559void Sema::AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE, 8560 Expr **Args, unsigned NumArgs, 8561 OverloadCandidateSet &CandidateSet, 8562 bool PartialOverloading) { 8563 8564#ifndef NDEBUG 8565 // Verify that ArgumentDependentLookup is consistent with the rules 8566 // in C++0x [basic.lookup.argdep]p3: 8567 // 8568 // Let X be the lookup set produced by unqualified lookup (3.4.1) 8569 // and let Y be the lookup set produced by argument dependent 8570 // lookup (defined as follows). If X contains 8571 // 8572 // -- a declaration of a class member, or 8573 // 8574 // -- a block-scope function declaration that is not a 8575 // using-declaration, or 8576 // 8577 // -- a declaration that is neither a function or a function 8578 // template 8579 // 8580 // then Y is empty. 8581 8582 if (ULE->requiresADL()) { 8583 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 8584 E = ULE->decls_end(); I != E; ++I) { 8585 assert(!(*I)->getDeclContext()->isRecord()); 8586 assert(isa<UsingShadowDecl>(*I) || 8587 !(*I)->getDeclContext()->isFunctionOrMethod()); 8588 assert((*I)->getUnderlyingDecl()->isFunctionOrFunctionTemplate()); 8589 } 8590 } 8591#endif 8592 8593 // It would be nice to avoid this copy. 8594 TemplateArgumentListInfo TABuffer; 8595 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 8596 if (ULE->hasExplicitTemplateArgs()) { 8597 ULE->copyTemplateArgumentsInto(TABuffer); 8598 ExplicitTemplateArgs = &TABuffer; 8599 } 8600 8601 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 8602 E = ULE->decls_end(); I != E; ++I) 8603 AddOverloadedCallCandidate(*this, I.getPair(), ExplicitTemplateArgs, 8604 Args, NumArgs, CandidateSet, 8605 PartialOverloading, /*KnownValid*/ true); 8606 8607 if (ULE->requiresADL()) 8608 AddArgumentDependentLookupCandidates(ULE->getName(), /*Operator*/ false, 8609 Args, NumArgs, 8610 ExplicitTemplateArgs, 8611 CandidateSet, 8612 PartialOverloading, 8613 ULE->isStdAssociatedNamespace()); 8614} 8615 8616/// Attempt to recover from an ill-formed use of a non-dependent name in a 8617/// template, where the non-dependent name was declared after the template 8618/// was defined. This is common in code written for a compilers which do not 8619/// correctly implement two-stage name lookup. 8620/// 8621/// Returns true if a viable candidate was found and a diagnostic was issued. 8622static bool 8623DiagnoseTwoPhaseLookup(Sema &SemaRef, SourceLocation FnLoc, 8624 const CXXScopeSpec &SS, LookupResult &R, 8625 TemplateArgumentListInfo *ExplicitTemplateArgs, 8626 Expr **Args, unsigned NumArgs) { 8627 if (SemaRef.ActiveTemplateInstantiations.empty() || !SS.isEmpty()) 8628 return false; 8629 8630 for (DeclContext *DC = SemaRef.CurContext; DC; DC = DC->getParent()) { 8631 SemaRef.LookupQualifiedName(R, DC); 8632 8633 if (!R.empty()) { 8634 R.suppressDiagnostics(); 8635 8636 if (isa<CXXRecordDecl>(DC)) { 8637 // Don't diagnose names we find in classes; we get much better 8638 // diagnostics for these from DiagnoseEmptyLookup. 8639 R.clear(); 8640 return false; 8641 } 8642 8643 OverloadCandidateSet Candidates(FnLoc); 8644 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 8645 AddOverloadedCallCandidate(SemaRef, I.getPair(), 8646 ExplicitTemplateArgs, Args, NumArgs, 8647 Candidates, false, /*KnownValid*/ false); 8648 8649 OverloadCandidateSet::iterator Best; 8650 if (Candidates.BestViableFunction(SemaRef, FnLoc, Best) != OR_Success) { 8651 // No viable functions. Don't bother the user with notes for functions 8652 // which don't work and shouldn't be found anyway. 8653 R.clear(); 8654 return false; 8655 } 8656 8657 // Find the namespaces where ADL would have looked, and suggest 8658 // declaring the function there instead. 8659 Sema::AssociatedNamespaceSet AssociatedNamespaces; 8660 Sema::AssociatedClassSet AssociatedClasses; 8661 SemaRef.FindAssociatedClassesAndNamespaces(Args, NumArgs, 8662 AssociatedNamespaces, 8663 AssociatedClasses); 8664 // Never suggest declaring a function within namespace 'std'. 8665 Sema::AssociatedNamespaceSet SuggestedNamespaces; 8666 if (DeclContext *Std = SemaRef.getStdNamespace()) { 8667 for (Sema::AssociatedNamespaceSet::iterator 8668 it = AssociatedNamespaces.begin(), 8669 end = AssociatedNamespaces.end(); it != end; ++it) { 8670 if (!Std->Encloses(*it)) 8671 SuggestedNamespaces.insert(*it); 8672 } 8673 } else { 8674 // Lacking the 'std::' namespace, use all of the associated namespaces. 8675 SuggestedNamespaces = AssociatedNamespaces; 8676 } 8677 8678 SemaRef.Diag(R.getNameLoc(), diag::err_not_found_by_two_phase_lookup) 8679 << R.getLookupName(); 8680 if (SuggestedNamespaces.empty()) { 8681 SemaRef.Diag(Best->Function->getLocation(), 8682 diag::note_not_found_by_two_phase_lookup) 8683 << R.getLookupName() << 0; 8684 } else if (SuggestedNamespaces.size() == 1) { 8685 SemaRef.Diag(Best->Function->getLocation(), 8686 diag::note_not_found_by_two_phase_lookup) 8687 << R.getLookupName() << 1 << *SuggestedNamespaces.begin(); 8688 } else { 8689 // FIXME: It would be useful to list the associated namespaces here, 8690 // but the diagnostics infrastructure doesn't provide a way to produce 8691 // a localized representation of a list of items. 8692 SemaRef.Diag(Best->Function->getLocation(), 8693 diag::note_not_found_by_two_phase_lookup) 8694 << R.getLookupName() << 2; 8695 } 8696 8697 // Try to recover by calling this function. 8698 return true; 8699 } 8700 8701 R.clear(); 8702 } 8703 8704 return false; 8705} 8706 8707/// Attempt to recover from ill-formed use of a non-dependent operator in a 8708/// template, where the non-dependent operator was declared after the template 8709/// was defined. 8710/// 8711/// Returns true if a viable candidate was found and a diagnostic was issued. 8712static bool 8713DiagnoseTwoPhaseOperatorLookup(Sema &SemaRef, OverloadedOperatorKind Op, 8714 SourceLocation OpLoc, 8715 Expr **Args, unsigned NumArgs) { 8716 DeclarationName OpName = 8717 SemaRef.Context.DeclarationNames.getCXXOperatorName(Op); 8718 LookupResult R(SemaRef, OpName, OpLoc, Sema::LookupOperatorName); 8719 return DiagnoseTwoPhaseLookup(SemaRef, OpLoc, CXXScopeSpec(), R, 8720 /*ExplicitTemplateArgs=*/0, Args, NumArgs); 8721} 8722 8723/// Attempts to recover from a call where no functions were found. 8724/// 8725/// Returns true if new candidates were found. 8726static ExprResult 8727BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn, 8728 UnresolvedLookupExpr *ULE, 8729 SourceLocation LParenLoc, 8730 Expr **Args, unsigned NumArgs, 8731 SourceLocation RParenLoc, 8732 bool EmptyLookup) { 8733 8734 CXXScopeSpec SS; 8735 SS.Adopt(ULE->getQualifierLoc()); 8736 8737 TemplateArgumentListInfo TABuffer; 8738 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 8739 if (ULE->hasExplicitTemplateArgs()) { 8740 ULE->copyTemplateArgumentsInto(TABuffer); 8741 ExplicitTemplateArgs = &TABuffer; 8742 } 8743 8744 LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(), 8745 Sema::LookupOrdinaryName); 8746 if (!DiagnoseTwoPhaseLookup(SemaRef, Fn->getExprLoc(), SS, R, 8747 ExplicitTemplateArgs, Args, NumArgs) && 8748 (!EmptyLookup || 8749 SemaRef.DiagnoseEmptyLookup(S, SS, R, Sema::CTC_Expression, 8750 ExplicitTemplateArgs, Args, NumArgs))) 8751 return ExprError(); 8752 8753 assert(!R.empty() && "lookup results empty despite recovery"); 8754 8755 // Build an implicit member call if appropriate. Just drop the 8756 // casts and such from the call, we don't really care. 8757 ExprResult NewFn = ExprError(); 8758 if ((*R.begin())->isCXXClassMember()) 8759 NewFn = SemaRef.BuildPossibleImplicitMemberExpr(SS, R, 8760 ExplicitTemplateArgs); 8761 else if (ExplicitTemplateArgs) 8762 NewFn = SemaRef.BuildTemplateIdExpr(SS, R, false, *ExplicitTemplateArgs); 8763 else 8764 NewFn = SemaRef.BuildDeclarationNameExpr(SS, R, false); 8765 8766 if (NewFn.isInvalid()) 8767 return ExprError(); 8768 8769 // This shouldn't cause an infinite loop because we're giving it 8770 // an expression with viable lookup results, which should never 8771 // end up here. 8772 return SemaRef.ActOnCallExpr(/*Scope*/ 0, NewFn.take(), LParenLoc, 8773 MultiExprArg(Args, NumArgs), RParenLoc); 8774} 8775 8776/// ResolveOverloadedCallFn - Given the call expression that calls Fn 8777/// (which eventually refers to the declaration Func) and the call 8778/// arguments Args/NumArgs, attempt to resolve the function call down 8779/// to a specific function. If overload resolution succeeds, returns 8780/// the function declaration produced by overload 8781/// resolution. Otherwise, emits diagnostics, deletes all of the 8782/// arguments and Fn, and returns NULL. 8783ExprResult 8784Sema::BuildOverloadedCallExpr(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE, 8785 SourceLocation LParenLoc, 8786 Expr **Args, unsigned NumArgs, 8787 SourceLocation RParenLoc, 8788 Expr *ExecConfig) { 8789#ifndef NDEBUG 8790 if (ULE->requiresADL()) { 8791 // To do ADL, we must have found an unqualified name. 8792 assert(!ULE->getQualifier() && "qualified name with ADL"); 8793 8794 // We don't perform ADL for implicit declarations of builtins. 8795 // Verify that this was correctly set up. 8796 FunctionDecl *F; 8797 if (ULE->decls_begin() + 1 == ULE->decls_end() && 8798 (F = dyn_cast<FunctionDecl>(*ULE->decls_begin())) && 8799 F->getBuiltinID() && F->isImplicit()) 8800 llvm_unreachable("performing ADL for builtin"); 8801 8802 // We don't perform ADL in C. 8803 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 8804 } else 8805 assert(!ULE->isStdAssociatedNamespace() && 8806 "std is associated namespace but not doing ADL"); 8807#endif 8808 8809 UnbridgedCastsSet UnbridgedCasts; 8810 if (checkArgPlaceholdersForOverload(*this, Args, NumArgs, UnbridgedCasts)) 8811 return ExprError(); 8812 8813 OverloadCandidateSet CandidateSet(Fn->getExprLoc()); 8814 8815 // Add the functions denoted by the callee to the set of candidate 8816 // functions, including those from argument-dependent lookup. 8817 AddOverloadedCallCandidates(ULE, Args, NumArgs, CandidateSet); 8818 8819 // If we found nothing, try to recover. 8820 // BuildRecoveryCallExpr diagnoses the error itself, so we just bail 8821 // out if it fails. 8822 if (CandidateSet.empty()) { 8823 // In Microsoft mode, if we are inside a template class member function then 8824 // create a type dependent CallExpr. The goal is to postpone name lookup 8825 // to instantiation time to be able to search into type dependent base 8826 // classes. 8827 if (getLangOptions().MicrosoftMode && CurContext->isDependentContext() && 8828 (isa<CXXMethodDecl>(CurContext) || isa<CXXRecordDecl>(CurContext))) { 8829 CallExpr *CE = new (Context) CallExpr(Context, Fn, Args, NumArgs, 8830 Context.DependentTy, VK_RValue, 8831 RParenLoc); 8832 CE->setTypeDependent(true); 8833 return Owned(CE); 8834 } 8835 return BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, Args, NumArgs, 8836 RParenLoc, /*EmptyLookup=*/true); 8837 } 8838 8839 UnbridgedCasts.restore(); 8840 8841 OverloadCandidateSet::iterator Best; 8842 switch (CandidateSet.BestViableFunction(*this, Fn->getLocStart(), Best)) { 8843 case OR_Success: { 8844 FunctionDecl *FDecl = Best->Function; 8845 MarkDeclarationReferenced(Fn->getExprLoc(), FDecl); 8846 CheckUnresolvedLookupAccess(ULE, Best->FoundDecl); 8847 DiagnoseUseOfDecl(FDecl, ULE->getNameLoc()); 8848 Fn = FixOverloadedFunctionReference(Fn, Best->FoundDecl, FDecl); 8849 return BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, RParenLoc, 8850 ExecConfig); 8851 } 8852 8853 case OR_No_Viable_Function: { 8854 // Try to recover by looking for viable functions which the user might 8855 // have meant to call. 8856 ExprResult Recovery = BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, 8857 Args, NumArgs, RParenLoc, 8858 /*EmptyLookup=*/false); 8859 if (!Recovery.isInvalid()) 8860 return Recovery; 8861 8862 Diag(Fn->getSourceRange().getBegin(), 8863 diag::err_ovl_no_viable_function_in_call) 8864 << ULE->getName() << Fn->getSourceRange(); 8865 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8866 break; 8867 } 8868 8869 case OR_Ambiguous: 8870 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_ambiguous_call) 8871 << ULE->getName() << Fn->getSourceRange(); 8872 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 8873 break; 8874 8875 case OR_Deleted: 8876 { 8877 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_deleted_call) 8878 << Best->Function->isDeleted() 8879 << ULE->getName() 8880 << getDeletedOrUnavailableSuffix(Best->Function) 8881 << Fn->getSourceRange(); 8882 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8883 8884 // We emitted an error for the unvailable/deleted function call but keep 8885 // the call in the AST. 8886 FunctionDecl *FDecl = Best->Function; 8887 Fn = FixOverloadedFunctionReference(Fn, Best->FoundDecl, FDecl); 8888 return BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, 8889 RParenLoc, ExecConfig); 8890 } 8891 break; 8892 } 8893 8894 // Overload resolution failed. 8895 return ExprError(); 8896} 8897 8898static bool IsOverloaded(const UnresolvedSetImpl &Functions) { 8899 return Functions.size() > 1 || 8900 (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); 8901} 8902 8903/// \brief Create a unary operation that may resolve to an overloaded 8904/// operator. 8905/// 8906/// \param OpLoc The location of the operator itself (e.g., '*'). 8907/// 8908/// \param OpcIn The UnaryOperator::Opcode that describes this 8909/// operator. 8910/// 8911/// \param Functions The set of non-member functions that will be 8912/// considered by overload resolution. The caller needs to build this 8913/// set based on the context using, e.g., 8914/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8915/// set should not contain any member functions; those will be added 8916/// by CreateOverloadedUnaryOp(). 8917/// 8918/// \param input The input argument. 8919ExprResult 8920Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn, 8921 const UnresolvedSetImpl &Fns, 8922 Expr *Input) { 8923 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 8924 8925 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc); 8926 assert(Op != OO_None && "Invalid opcode for overloaded unary operator"); 8927 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8928 // TODO: provide better source location info. 8929 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8930 8931 if (checkPlaceholderForOverload(*this, Input)) 8932 return ExprError(); 8933 8934 Expr *Args[2] = { Input, 0 }; 8935 unsigned NumArgs = 1; 8936 8937 // For post-increment and post-decrement, add the implicit '0' as 8938 // the second argument, so that we know this is a post-increment or 8939 // post-decrement. 8940 if (Opc == UO_PostInc || Opc == UO_PostDec) { 8941 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false); 8942 Args[1] = IntegerLiteral::Create(Context, Zero, Context.IntTy, 8943 SourceLocation()); 8944 NumArgs = 2; 8945 } 8946 8947 if (Input->isTypeDependent()) { 8948 if (Fns.empty()) 8949 return Owned(new (Context) UnaryOperator(Input, 8950 Opc, 8951 Context.DependentTy, 8952 VK_RValue, OK_Ordinary, 8953 OpLoc)); 8954 8955 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8956 UnresolvedLookupExpr *Fn 8957 = UnresolvedLookupExpr::Create(Context, NamingClass, 8958 NestedNameSpecifierLoc(), OpNameInfo, 8959 /*ADL*/ true, IsOverloaded(Fns), 8960 Fns.begin(), Fns.end()); 8961 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8962 &Args[0], NumArgs, 8963 Context.DependentTy, 8964 VK_RValue, 8965 OpLoc)); 8966 } 8967 8968 // Build an empty overload set. 8969 OverloadCandidateSet CandidateSet(OpLoc); 8970 8971 // Add the candidates from the given function set. 8972 AddFunctionCandidates(Fns, &Args[0], NumArgs, CandidateSet, false); 8973 8974 // Add operator candidates that are member functions. 8975 AddMemberOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8976 8977 // Add candidates from ADL. 8978 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8979 Args, NumArgs, 8980 /*ExplicitTemplateArgs*/ 0, 8981 CandidateSet); 8982 8983 // Add builtin operator candidates. 8984 AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8985 8986 bool HadMultipleCandidates = (CandidateSet.size() > 1); 8987 8988 // Perform overload resolution. 8989 OverloadCandidateSet::iterator Best; 8990 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8991 case OR_Success: { 8992 // We found a built-in operator or an overloaded operator. 8993 FunctionDecl *FnDecl = Best->Function; 8994 8995 if (FnDecl) { 8996 // We matched an overloaded operator. Build a call to that 8997 // operator. 8998 8999 MarkDeclarationReferenced(OpLoc, FnDecl); 9000 9001 // Convert the arguments. 9002 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 9003 CheckMemberOperatorAccess(OpLoc, Args[0], 0, Best->FoundDecl); 9004 9005 ExprResult InputRes = 9006 PerformObjectArgumentInitialization(Input, /*Qualifier=*/0, 9007 Best->FoundDecl, Method); 9008 if (InputRes.isInvalid()) 9009 return ExprError(); 9010 Input = InputRes.take(); 9011 } else { 9012 // Convert the arguments. 9013 ExprResult InputInit 9014 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 9015 Context, 9016 FnDecl->getParamDecl(0)), 9017 SourceLocation(), 9018 Input); 9019 if (InputInit.isInvalid()) 9020 return ExprError(); 9021 Input = InputInit.take(); 9022 } 9023 9024 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 9025 9026 // Determine the result type. 9027 QualType ResultTy = FnDecl->getResultType(); 9028 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9029 ResultTy = ResultTy.getNonLValueExprType(Context); 9030 9031 // Build the actual expression node. 9032 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, 9033 HadMultipleCandidates); 9034 if (FnExpr.isInvalid()) 9035 return ExprError(); 9036 9037 Args[0] = Input; 9038 CallExpr *TheCall = 9039 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 9040 Args, NumArgs, ResultTy, VK, OpLoc); 9041 9042 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 9043 FnDecl)) 9044 return ExprError(); 9045 9046 return MaybeBindToTemporary(TheCall); 9047 } else { 9048 // We matched a built-in operator. Convert the arguments, then 9049 // break out so that we will build the appropriate built-in 9050 // operator node. 9051 ExprResult InputRes = 9052 PerformImplicitConversion(Input, Best->BuiltinTypes.ParamTypes[0], 9053 Best->Conversions[0], AA_Passing); 9054 if (InputRes.isInvalid()) 9055 return ExprError(); 9056 Input = InputRes.take(); 9057 break; 9058 } 9059 } 9060 9061 case OR_No_Viable_Function: 9062 // This is an erroneous use of an operator which can be overloaded by 9063 // a non-member function. Check for non-member operators which were 9064 // defined too late to be candidates. 9065 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args, NumArgs)) 9066 // FIXME: Recover by calling the found function. 9067 return ExprError(); 9068 9069 // No viable function; fall through to handling this as a 9070 // built-in operator, which will produce an error message for us. 9071 break; 9072 9073 case OR_Ambiguous: 9074 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 9075 << UnaryOperator::getOpcodeStr(Opc) 9076 << Input->getType() 9077 << Input->getSourceRange(); 9078 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs, 9079 UnaryOperator::getOpcodeStr(Opc), OpLoc); 9080 return ExprError(); 9081 9082 case OR_Deleted: 9083 Diag(OpLoc, diag::err_ovl_deleted_oper) 9084 << Best->Function->isDeleted() 9085 << UnaryOperator::getOpcodeStr(Opc) 9086 << getDeletedOrUnavailableSuffix(Best->Function) 9087 << Input->getSourceRange(); 9088 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs, 9089 UnaryOperator::getOpcodeStr(Opc), OpLoc); 9090 return ExprError(); 9091 } 9092 9093 // Either we found no viable overloaded operator or we matched a 9094 // built-in operator. In either case, fall through to trying to 9095 // build a built-in operation. 9096 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 9097} 9098 9099/// \brief Create a binary operation that may resolve to an overloaded 9100/// operator. 9101/// 9102/// \param OpLoc The location of the operator itself (e.g., '+'). 9103/// 9104/// \param OpcIn The BinaryOperator::Opcode that describes this 9105/// operator. 9106/// 9107/// \param Functions The set of non-member functions that will be 9108/// considered by overload resolution. The caller needs to build this 9109/// set based on the context using, e.g., 9110/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 9111/// set should not contain any member functions; those will be added 9112/// by CreateOverloadedBinOp(). 9113/// 9114/// \param LHS Left-hand argument. 9115/// \param RHS Right-hand argument. 9116ExprResult 9117Sema::CreateOverloadedBinOp(SourceLocation OpLoc, 9118 unsigned OpcIn, 9119 const UnresolvedSetImpl &Fns, 9120 Expr *LHS, Expr *RHS) { 9121 Expr *Args[2] = { LHS, RHS }; 9122 LHS=RHS=0; //Please use only Args instead of LHS/RHS couple 9123 9124 BinaryOperator::Opcode Opc = static_cast<BinaryOperator::Opcode>(OpcIn); 9125 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc); 9126 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 9127 9128 // If either side is type-dependent, create an appropriate dependent 9129 // expression. 9130 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 9131 if (Fns.empty()) { 9132 // If there are no functions to store, just build a dependent 9133 // BinaryOperator or CompoundAssignment. 9134 if (Opc <= BO_Assign || Opc > BO_OrAssign) 9135 return Owned(new (Context) BinaryOperator(Args[0], Args[1], Opc, 9136 Context.DependentTy, 9137 VK_RValue, OK_Ordinary, 9138 OpLoc)); 9139 9140 return Owned(new (Context) CompoundAssignOperator(Args[0], Args[1], Opc, 9141 Context.DependentTy, 9142 VK_LValue, 9143 OK_Ordinary, 9144 Context.DependentTy, 9145 Context.DependentTy, 9146 OpLoc)); 9147 } 9148 9149 // FIXME: save results of ADL from here? 9150 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 9151 // TODO: provide better source location info in DNLoc component. 9152 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 9153 UnresolvedLookupExpr *Fn 9154 = UnresolvedLookupExpr::Create(Context, NamingClass, 9155 NestedNameSpecifierLoc(), OpNameInfo, 9156 /*ADL*/ true, IsOverloaded(Fns), 9157 Fns.begin(), Fns.end()); 9158 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 9159 Args, 2, 9160 Context.DependentTy, 9161 VK_RValue, 9162 OpLoc)); 9163 } 9164 9165 // Always do placeholder-like conversions on the RHS. 9166 if (checkPlaceholderForOverload(*this, Args[1])) 9167 return ExprError(); 9168 9169 // Do placeholder-like conversion on the LHS; note that we should 9170 // not get here with a PseudoObject LHS. 9171 assert(Args[0]->getObjectKind() != OK_ObjCProperty); 9172 if (checkPlaceholderForOverload(*this, Args[0])) 9173 return ExprError(); 9174 9175 // If this is the assignment operator, we only perform overload resolution 9176 // if the left-hand side is a class or enumeration type. This is actually 9177 // a hack. The standard requires that we do overload resolution between the 9178 // various built-in candidates, but as DR507 points out, this can lead to 9179 // problems. So we do it this way, which pretty much follows what GCC does. 9180 // Note that we go the traditional code path for compound assignment forms. 9181 if (Opc == BO_Assign && !Args[0]->getType()->isOverloadableType()) 9182 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 9183 9184 // If this is the .* operator, which is not overloadable, just 9185 // create a built-in binary operator. 9186 if (Opc == BO_PtrMemD) 9187 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 9188 9189 // Build an empty overload set. 9190 OverloadCandidateSet CandidateSet(OpLoc); 9191 9192 // Add the candidates from the given function set. 9193 AddFunctionCandidates(Fns, Args, 2, CandidateSet, false); 9194 9195 // Add operator candidates that are member functions. 9196 AddMemberOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 9197 9198 // Add candidates from ADL. 9199 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 9200 Args, 2, 9201 /*ExplicitTemplateArgs*/ 0, 9202 CandidateSet); 9203 9204 // Add builtin operator candidates. 9205 AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 9206 9207 bool HadMultipleCandidates = (CandidateSet.size() > 1); 9208 9209 // Perform overload resolution. 9210 OverloadCandidateSet::iterator Best; 9211 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 9212 case OR_Success: { 9213 // We found a built-in operator or an overloaded operator. 9214 FunctionDecl *FnDecl = Best->Function; 9215 9216 if (FnDecl) { 9217 // We matched an overloaded operator. Build a call to that 9218 // operator. 9219 9220 MarkDeclarationReferenced(OpLoc, FnDecl); 9221 9222 // Convert the arguments. 9223 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 9224 // Best->Access is only meaningful for class members. 9225 CheckMemberOperatorAccess(OpLoc, Args[0], Args[1], Best->FoundDecl); 9226 9227 ExprResult Arg1 = 9228 PerformCopyInitialization( 9229 InitializedEntity::InitializeParameter(Context, 9230 FnDecl->getParamDecl(0)), 9231 SourceLocation(), Owned(Args[1])); 9232 if (Arg1.isInvalid()) 9233 return ExprError(); 9234 9235 ExprResult Arg0 = 9236 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 9237 Best->FoundDecl, Method); 9238 if (Arg0.isInvalid()) 9239 return ExprError(); 9240 Args[0] = Arg0.takeAs<Expr>(); 9241 Args[1] = RHS = Arg1.takeAs<Expr>(); 9242 } else { 9243 // Convert the arguments. 9244 ExprResult Arg0 = PerformCopyInitialization( 9245 InitializedEntity::InitializeParameter(Context, 9246 FnDecl->getParamDecl(0)), 9247 SourceLocation(), Owned(Args[0])); 9248 if (Arg0.isInvalid()) 9249 return ExprError(); 9250 9251 ExprResult Arg1 = 9252 PerformCopyInitialization( 9253 InitializedEntity::InitializeParameter(Context, 9254 FnDecl->getParamDecl(1)), 9255 SourceLocation(), Owned(Args[1])); 9256 if (Arg1.isInvalid()) 9257 return ExprError(); 9258 Args[0] = LHS = Arg0.takeAs<Expr>(); 9259 Args[1] = RHS = Arg1.takeAs<Expr>(); 9260 } 9261 9262 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 9263 9264 // Determine the result type. 9265 QualType ResultTy = FnDecl->getResultType(); 9266 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9267 ResultTy = ResultTy.getNonLValueExprType(Context); 9268 9269 // Build the actual expression node. 9270 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, 9271 HadMultipleCandidates, OpLoc); 9272 if (FnExpr.isInvalid()) 9273 return ExprError(); 9274 9275 CXXOperatorCallExpr *TheCall = 9276 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 9277 Args, 2, ResultTy, VK, OpLoc); 9278 9279 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 9280 FnDecl)) 9281 return ExprError(); 9282 9283 return MaybeBindToTemporary(TheCall); 9284 } else { 9285 // We matched a built-in operator. Convert the arguments, then 9286 // break out so that we will build the appropriate built-in 9287 // operator node. 9288 ExprResult ArgsRes0 = 9289 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 9290 Best->Conversions[0], AA_Passing); 9291 if (ArgsRes0.isInvalid()) 9292 return ExprError(); 9293 Args[0] = ArgsRes0.take(); 9294 9295 ExprResult ArgsRes1 = 9296 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 9297 Best->Conversions[1], AA_Passing); 9298 if (ArgsRes1.isInvalid()) 9299 return ExprError(); 9300 Args[1] = ArgsRes1.take(); 9301 break; 9302 } 9303 } 9304 9305 case OR_No_Viable_Function: { 9306 // C++ [over.match.oper]p9: 9307 // If the operator is the operator , [...] and there are no 9308 // viable functions, then the operator is assumed to be the 9309 // built-in operator and interpreted according to clause 5. 9310 if (Opc == BO_Comma) 9311 break; 9312 9313 // For class as left operand for assignment or compound assigment 9314 // operator do not fall through to handling in built-in, but report that 9315 // no overloaded assignment operator found 9316 ExprResult Result = ExprError(); 9317 if (Args[0]->getType()->isRecordType() && 9318 Opc >= BO_Assign && Opc <= BO_OrAssign) { 9319 Diag(OpLoc, diag::err_ovl_no_viable_oper) 9320 << BinaryOperator::getOpcodeStr(Opc) 9321 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9322 } else { 9323 // This is an erroneous use of an operator which can be overloaded by 9324 // a non-member function. Check for non-member operators which were 9325 // defined too late to be candidates. 9326 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args, 2)) 9327 // FIXME: Recover by calling the found function. 9328 return ExprError(); 9329 9330 // No viable function; try to create a built-in operation, which will 9331 // produce an error. Then, show the non-viable candidates. 9332 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 9333 } 9334 assert(Result.isInvalid() && 9335 "C++ binary operator overloading is missing candidates!"); 9336 if (Result.isInvalid()) 9337 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 9338 BinaryOperator::getOpcodeStr(Opc), OpLoc); 9339 return move(Result); 9340 } 9341 9342 case OR_Ambiguous: 9343 Diag(OpLoc, diag::err_ovl_ambiguous_oper_binary) 9344 << BinaryOperator::getOpcodeStr(Opc) 9345 << Args[0]->getType() << Args[1]->getType() 9346 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9347 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 9348 BinaryOperator::getOpcodeStr(Opc), OpLoc); 9349 return ExprError(); 9350 9351 case OR_Deleted: 9352 Diag(OpLoc, diag::err_ovl_deleted_oper) 9353 << Best->Function->isDeleted() 9354 << BinaryOperator::getOpcodeStr(Opc) 9355 << getDeletedOrUnavailableSuffix(Best->Function) 9356 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9357 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 9358 BinaryOperator::getOpcodeStr(Opc), OpLoc); 9359 return ExprError(); 9360 } 9361 9362 // We matched a built-in operator; build it. 9363 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 9364} 9365 9366ExprResult 9367Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc, 9368 SourceLocation RLoc, 9369 Expr *Base, Expr *Idx) { 9370 Expr *Args[2] = { Base, Idx }; 9371 DeclarationName OpName = 9372 Context.DeclarationNames.getCXXOperatorName(OO_Subscript); 9373 9374 // If either side is type-dependent, create an appropriate dependent 9375 // expression. 9376 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 9377 9378 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 9379 // CHECKME: no 'operator' keyword? 9380 DeclarationNameInfo OpNameInfo(OpName, LLoc); 9381 OpNameInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc)); 9382 UnresolvedLookupExpr *Fn 9383 = UnresolvedLookupExpr::Create(Context, NamingClass, 9384 NestedNameSpecifierLoc(), OpNameInfo, 9385 /*ADL*/ true, /*Overloaded*/ false, 9386 UnresolvedSetIterator(), 9387 UnresolvedSetIterator()); 9388 // Can't add any actual overloads yet 9389 9390 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, Fn, 9391 Args, 2, 9392 Context.DependentTy, 9393 VK_RValue, 9394 RLoc)); 9395 } 9396 9397 // Handle placeholders on both operands. 9398 if (checkPlaceholderForOverload(*this, Args[0])) 9399 return ExprError(); 9400 if (checkPlaceholderForOverload(*this, Args[1])) 9401 return ExprError(); 9402 9403 // Build an empty overload set. 9404 OverloadCandidateSet CandidateSet(LLoc); 9405 9406 // Subscript can only be overloaded as a member function. 9407 9408 // Add operator candidates that are member functions. 9409 AddMemberOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 9410 9411 // Add builtin operator candidates. 9412 AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 9413 9414 bool HadMultipleCandidates = (CandidateSet.size() > 1); 9415 9416 // Perform overload resolution. 9417 OverloadCandidateSet::iterator Best; 9418 switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) { 9419 case OR_Success: { 9420 // We found a built-in operator or an overloaded operator. 9421 FunctionDecl *FnDecl = Best->Function; 9422 9423 if (FnDecl) { 9424 // We matched an overloaded operator. Build a call to that 9425 // operator. 9426 9427 MarkDeclarationReferenced(LLoc, FnDecl); 9428 9429 CheckMemberOperatorAccess(LLoc, Args[0], Args[1], Best->FoundDecl); 9430 DiagnoseUseOfDecl(Best->FoundDecl, LLoc); 9431 9432 // Convert the arguments. 9433 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 9434 ExprResult Arg0 = 9435 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 9436 Best->FoundDecl, Method); 9437 if (Arg0.isInvalid()) 9438 return ExprError(); 9439 Args[0] = Arg0.take(); 9440 9441 // Convert the arguments. 9442 ExprResult InputInit 9443 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 9444 Context, 9445 FnDecl->getParamDecl(0)), 9446 SourceLocation(), 9447 Owned(Args[1])); 9448 if (InputInit.isInvalid()) 9449 return ExprError(); 9450 9451 Args[1] = InputInit.takeAs<Expr>(); 9452 9453 // Determine the result type 9454 QualType ResultTy = FnDecl->getResultType(); 9455 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9456 ResultTy = ResultTy.getNonLValueExprType(Context); 9457 9458 // Build the actual expression node. 9459 DeclarationNameLoc LocInfo; 9460 LocInfo.CXXOperatorName.BeginOpNameLoc = LLoc.getRawEncoding(); 9461 LocInfo.CXXOperatorName.EndOpNameLoc = RLoc.getRawEncoding(); 9462 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, 9463 HadMultipleCandidates, 9464 LLoc, LocInfo); 9465 if (FnExpr.isInvalid()) 9466 return ExprError(); 9467 9468 CXXOperatorCallExpr *TheCall = 9469 new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 9470 FnExpr.take(), Args, 2, 9471 ResultTy, VK, RLoc); 9472 9473 if (CheckCallReturnType(FnDecl->getResultType(), LLoc, TheCall, 9474 FnDecl)) 9475 return ExprError(); 9476 9477 return MaybeBindToTemporary(TheCall); 9478 } else { 9479 // We matched a built-in operator. Convert the arguments, then 9480 // break out so that we will build the appropriate built-in 9481 // operator node. 9482 ExprResult ArgsRes0 = 9483 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 9484 Best->Conversions[0], AA_Passing); 9485 if (ArgsRes0.isInvalid()) 9486 return ExprError(); 9487 Args[0] = ArgsRes0.take(); 9488 9489 ExprResult ArgsRes1 = 9490 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 9491 Best->Conversions[1], AA_Passing); 9492 if (ArgsRes1.isInvalid()) 9493 return ExprError(); 9494 Args[1] = ArgsRes1.take(); 9495 9496 break; 9497 } 9498 } 9499 9500 case OR_No_Viable_Function: { 9501 if (CandidateSet.empty()) 9502 Diag(LLoc, diag::err_ovl_no_oper) 9503 << Args[0]->getType() << /*subscript*/ 0 9504 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9505 else 9506 Diag(LLoc, diag::err_ovl_no_viable_subscript) 9507 << Args[0]->getType() 9508 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9509 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 9510 "[]", LLoc); 9511 return ExprError(); 9512 } 9513 9514 case OR_Ambiguous: 9515 Diag(LLoc, diag::err_ovl_ambiguous_oper_binary) 9516 << "[]" 9517 << Args[0]->getType() << Args[1]->getType() 9518 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9519 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 9520 "[]", LLoc); 9521 return ExprError(); 9522 9523 case OR_Deleted: 9524 Diag(LLoc, diag::err_ovl_deleted_oper) 9525 << Best->Function->isDeleted() << "[]" 9526 << getDeletedOrUnavailableSuffix(Best->Function) 9527 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9528 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 9529 "[]", LLoc); 9530 return ExprError(); 9531 } 9532 9533 // We matched a built-in operator; build it. 9534 return CreateBuiltinArraySubscriptExpr(Args[0], LLoc, Args[1], RLoc); 9535} 9536 9537/// BuildCallToMemberFunction - Build a call to a member 9538/// function. MemExpr is the expression that refers to the member 9539/// function (and includes the object parameter), Args/NumArgs are the 9540/// arguments to the function call (not including the object 9541/// parameter). The caller needs to validate that the member 9542/// expression refers to a non-static member function or an overloaded 9543/// member function. 9544ExprResult 9545Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE, 9546 SourceLocation LParenLoc, Expr **Args, 9547 unsigned NumArgs, SourceLocation RParenLoc) { 9548 assert(MemExprE->getType() == Context.BoundMemberTy || 9549 MemExprE->getType() == Context.OverloadTy); 9550 9551 // Dig out the member expression. This holds both the object 9552 // argument and the member function we're referring to. 9553 Expr *NakedMemExpr = MemExprE->IgnoreParens(); 9554 9555 // Determine whether this is a call to a pointer-to-member function. 9556 if (BinaryOperator *op = dyn_cast<BinaryOperator>(NakedMemExpr)) { 9557 assert(op->getType() == Context.BoundMemberTy); 9558 assert(op->getOpcode() == BO_PtrMemD || op->getOpcode() == BO_PtrMemI); 9559 9560 QualType fnType = 9561 op->getRHS()->getType()->castAs<MemberPointerType>()->getPointeeType(); 9562 9563 const FunctionProtoType *proto = fnType->castAs<FunctionProtoType>(); 9564 QualType resultType = proto->getCallResultType(Context); 9565 ExprValueKind valueKind = Expr::getValueKindForType(proto->getResultType()); 9566 9567 // Check that the object type isn't more qualified than the 9568 // member function we're calling. 9569 Qualifiers funcQuals = Qualifiers::fromCVRMask(proto->getTypeQuals()); 9570 9571 QualType objectType = op->getLHS()->getType(); 9572 if (op->getOpcode() == BO_PtrMemI) 9573 objectType = objectType->castAs<PointerType>()->getPointeeType(); 9574 Qualifiers objectQuals = objectType.getQualifiers(); 9575 9576 Qualifiers difference = objectQuals - funcQuals; 9577 difference.removeObjCGCAttr(); 9578 difference.removeAddressSpace(); 9579 if (difference) { 9580 std::string qualsString = difference.getAsString(); 9581 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals) 9582 << fnType.getUnqualifiedType() 9583 << qualsString 9584 << (qualsString.find(' ') == std::string::npos ? 1 : 2); 9585 } 9586 9587 CXXMemberCallExpr *call 9588 = new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 9589 resultType, valueKind, RParenLoc); 9590 9591 if (CheckCallReturnType(proto->getResultType(), 9592 op->getRHS()->getSourceRange().getBegin(), 9593 call, 0)) 9594 return ExprError(); 9595 9596 if (ConvertArgumentsForCall(call, op, 0, proto, Args, NumArgs, RParenLoc)) 9597 return ExprError(); 9598 9599 return MaybeBindToTemporary(call); 9600 } 9601 9602 UnbridgedCastsSet UnbridgedCasts; 9603 if (checkArgPlaceholdersForOverload(*this, Args, NumArgs, UnbridgedCasts)) 9604 return ExprError(); 9605 9606 MemberExpr *MemExpr; 9607 CXXMethodDecl *Method = 0; 9608 DeclAccessPair FoundDecl = DeclAccessPair::make(0, AS_public); 9609 NestedNameSpecifier *Qualifier = 0; 9610 if (isa<MemberExpr>(NakedMemExpr)) { 9611 MemExpr = cast<MemberExpr>(NakedMemExpr); 9612 Method = cast<CXXMethodDecl>(MemExpr->getMemberDecl()); 9613 FoundDecl = MemExpr->getFoundDecl(); 9614 Qualifier = MemExpr->getQualifier(); 9615 UnbridgedCasts.restore(); 9616 } else { 9617 UnresolvedMemberExpr *UnresExpr = cast<UnresolvedMemberExpr>(NakedMemExpr); 9618 Qualifier = UnresExpr->getQualifier(); 9619 9620 QualType ObjectType = UnresExpr->getBaseType(); 9621 Expr::Classification ObjectClassification 9622 = UnresExpr->isArrow()? Expr::Classification::makeSimpleLValue() 9623 : UnresExpr->getBase()->Classify(Context); 9624 9625 // Add overload candidates 9626 OverloadCandidateSet CandidateSet(UnresExpr->getMemberLoc()); 9627 9628 // FIXME: avoid copy. 9629 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9630 if (UnresExpr->hasExplicitTemplateArgs()) { 9631 UnresExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 9632 TemplateArgs = &TemplateArgsBuffer; 9633 } 9634 9635 for (UnresolvedMemberExpr::decls_iterator I = UnresExpr->decls_begin(), 9636 E = UnresExpr->decls_end(); I != E; ++I) { 9637 9638 NamedDecl *Func = *I; 9639 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(Func->getDeclContext()); 9640 if (isa<UsingShadowDecl>(Func)) 9641 Func = cast<UsingShadowDecl>(Func)->getTargetDecl(); 9642 9643 9644 // Microsoft supports direct constructor calls. 9645 if (getLangOptions().MicrosoftExt && isa<CXXConstructorDecl>(Func)) { 9646 AddOverloadCandidate(cast<CXXConstructorDecl>(Func), I.getPair(), Args, NumArgs, 9647 CandidateSet); 9648 } else if ((Method = dyn_cast<CXXMethodDecl>(Func))) { 9649 // If explicit template arguments were provided, we can't call a 9650 // non-template member function. 9651 if (TemplateArgs) 9652 continue; 9653 9654 AddMethodCandidate(Method, I.getPair(), ActingDC, ObjectType, 9655 ObjectClassification, 9656 Args, NumArgs, CandidateSet, 9657 /*SuppressUserConversions=*/false); 9658 } else { 9659 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(Func), 9660 I.getPair(), ActingDC, TemplateArgs, 9661 ObjectType, ObjectClassification, 9662 Args, NumArgs, CandidateSet, 9663 /*SuppressUsedConversions=*/false); 9664 } 9665 } 9666 9667 DeclarationName DeclName = UnresExpr->getMemberName(); 9668 9669 UnbridgedCasts.restore(); 9670 9671 OverloadCandidateSet::iterator Best; 9672 switch (CandidateSet.BestViableFunction(*this, UnresExpr->getLocStart(), 9673 Best)) { 9674 case OR_Success: 9675 Method = cast<CXXMethodDecl>(Best->Function); 9676 MarkDeclarationReferenced(UnresExpr->getMemberLoc(), Method); 9677 FoundDecl = Best->FoundDecl; 9678 CheckUnresolvedMemberAccess(UnresExpr, Best->FoundDecl); 9679 DiagnoseUseOfDecl(Best->FoundDecl, UnresExpr->getNameLoc()); 9680 break; 9681 9682 case OR_No_Viable_Function: 9683 Diag(UnresExpr->getMemberLoc(), 9684 diag::err_ovl_no_viable_member_function_in_call) 9685 << DeclName << MemExprE->getSourceRange(); 9686 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9687 // FIXME: Leaking incoming expressions! 9688 return ExprError(); 9689 9690 case OR_Ambiguous: 9691 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_ambiguous_member_call) 9692 << DeclName << MemExprE->getSourceRange(); 9693 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9694 // FIXME: Leaking incoming expressions! 9695 return ExprError(); 9696 9697 case OR_Deleted: 9698 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_deleted_member_call) 9699 << Best->Function->isDeleted() 9700 << DeclName 9701 << getDeletedOrUnavailableSuffix(Best->Function) 9702 << MemExprE->getSourceRange(); 9703 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9704 // FIXME: Leaking incoming expressions! 9705 return ExprError(); 9706 } 9707 9708 MemExprE = FixOverloadedFunctionReference(MemExprE, FoundDecl, Method); 9709 9710 // If overload resolution picked a static member, build a 9711 // non-member call based on that function. 9712 if (Method->isStatic()) { 9713 return BuildResolvedCallExpr(MemExprE, Method, LParenLoc, 9714 Args, NumArgs, RParenLoc); 9715 } 9716 9717 MemExpr = cast<MemberExpr>(MemExprE->IgnoreParens()); 9718 } 9719 9720 QualType ResultType = Method->getResultType(); 9721 ExprValueKind VK = Expr::getValueKindForType(ResultType); 9722 ResultType = ResultType.getNonLValueExprType(Context); 9723 9724 assert(Method && "Member call to something that isn't a method?"); 9725 CXXMemberCallExpr *TheCall = 9726 new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 9727 ResultType, VK, RParenLoc); 9728 9729 // Check for a valid return type. 9730 if (CheckCallReturnType(Method->getResultType(), MemExpr->getMemberLoc(), 9731 TheCall, Method)) 9732 return ExprError(); 9733 9734 // Convert the object argument (for a non-static member function call). 9735 // We only need to do this if there was actually an overload; otherwise 9736 // it was done at lookup. 9737 if (!Method->isStatic()) { 9738 ExprResult ObjectArg = 9739 PerformObjectArgumentInitialization(MemExpr->getBase(), Qualifier, 9740 FoundDecl, Method); 9741 if (ObjectArg.isInvalid()) 9742 return ExprError(); 9743 MemExpr->setBase(ObjectArg.take()); 9744 } 9745 9746 // Convert the rest of the arguments 9747 const FunctionProtoType *Proto = 9748 Method->getType()->getAs<FunctionProtoType>(); 9749 if (ConvertArgumentsForCall(TheCall, MemExpr, Method, Proto, Args, NumArgs, 9750 RParenLoc)) 9751 return ExprError(); 9752 9753 if (CheckFunctionCall(Method, TheCall)) 9754 return ExprError(); 9755 9756 if ((isa<CXXConstructorDecl>(CurContext) || 9757 isa<CXXDestructorDecl>(CurContext)) && 9758 TheCall->getMethodDecl()->isPure()) { 9759 const CXXMethodDecl *MD = TheCall->getMethodDecl(); 9760 9761 if (isa<CXXThisExpr>(MemExpr->getBase()->IgnoreParenCasts())) { 9762 Diag(MemExpr->getLocStart(), 9763 diag::warn_call_to_pure_virtual_member_function_from_ctor_dtor) 9764 << MD->getDeclName() << isa<CXXDestructorDecl>(CurContext) 9765 << MD->getParent()->getDeclName(); 9766 9767 Diag(MD->getLocStart(), diag::note_previous_decl) << MD->getDeclName(); 9768 } 9769 } 9770 return MaybeBindToTemporary(TheCall); 9771} 9772 9773/// BuildCallToObjectOfClassType - Build a call to an object of class 9774/// type (C++ [over.call.object]), which can end up invoking an 9775/// overloaded function call operator (@c operator()) or performing a 9776/// user-defined conversion on the object argument. 9777ExprResult 9778Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj, 9779 SourceLocation LParenLoc, 9780 Expr **Args, unsigned NumArgs, 9781 SourceLocation RParenLoc) { 9782 if (checkPlaceholderForOverload(*this, Obj)) 9783 return ExprError(); 9784 ExprResult Object = Owned(Obj); 9785 9786 UnbridgedCastsSet UnbridgedCasts; 9787 if (checkArgPlaceholdersForOverload(*this, Args, NumArgs, UnbridgedCasts)) 9788 return ExprError(); 9789 9790 assert(Object.get()->getType()->isRecordType() && "Requires object type argument"); 9791 const RecordType *Record = Object.get()->getType()->getAs<RecordType>(); 9792 9793 // C++ [over.call.object]p1: 9794 // If the primary-expression E in the function call syntax 9795 // evaluates to a class object of type "cv T", then the set of 9796 // candidate functions includes at least the function call 9797 // operators of T. The function call operators of T are obtained by 9798 // ordinary lookup of the name operator() in the context of 9799 // (E).operator(). 9800 OverloadCandidateSet CandidateSet(LParenLoc); 9801 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call); 9802 9803 if (RequireCompleteType(LParenLoc, Object.get()->getType(), 9804 PDiag(diag::err_incomplete_object_call) 9805 << Object.get()->getSourceRange())) 9806 return true; 9807 9808 LookupResult R(*this, OpName, LParenLoc, LookupOrdinaryName); 9809 LookupQualifiedName(R, Record->getDecl()); 9810 R.suppressDiagnostics(); 9811 9812 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9813 Oper != OperEnd; ++Oper) { 9814 AddMethodCandidate(Oper.getPair(), Object.get()->getType(), 9815 Object.get()->Classify(Context), Args, NumArgs, CandidateSet, 9816 /*SuppressUserConversions=*/ false); 9817 } 9818 9819 // C++ [over.call.object]p2: 9820 // In addition, for each (non-explicit in C++0x) conversion function 9821 // declared in T of the form 9822 // 9823 // operator conversion-type-id () cv-qualifier; 9824 // 9825 // where cv-qualifier is the same cv-qualification as, or a 9826 // greater cv-qualification than, cv, and where conversion-type-id 9827 // denotes the type "pointer to function of (P1,...,Pn) returning 9828 // R", or the type "reference to pointer to function of 9829 // (P1,...,Pn) returning R", or the type "reference to function 9830 // of (P1,...,Pn) returning R", a surrogate call function [...] 9831 // is also considered as a candidate function. Similarly, 9832 // surrogate call functions are added to the set of candidate 9833 // functions for each conversion function declared in an 9834 // accessible base class provided the function is not hidden 9835 // within T by another intervening declaration. 9836 const UnresolvedSetImpl *Conversions 9837 = cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions(); 9838 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 9839 E = Conversions->end(); I != E; ++I) { 9840 NamedDecl *D = *I; 9841 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 9842 if (isa<UsingShadowDecl>(D)) 9843 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 9844 9845 // Skip over templated conversion functions; they aren't 9846 // surrogates. 9847 if (isa<FunctionTemplateDecl>(D)) 9848 continue; 9849 9850 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 9851 if (!Conv->isExplicit()) { 9852 // Strip the reference type (if any) and then the pointer type (if 9853 // any) to get down to what might be a function type. 9854 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 9855 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 9856 ConvType = ConvPtrType->getPointeeType(); 9857 9858 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>()) 9859 { 9860 AddSurrogateCandidate(Conv, I.getPair(), ActingContext, Proto, 9861 Object.get(), Args, NumArgs, CandidateSet); 9862 } 9863 } 9864 } 9865 9866 bool HadMultipleCandidates = (CandidateSet.size() > 1); 9867 9868 // Perform overload resolution. 9869 OverloadCandidateSet::iterator Best; 9870 switch (CandidateSet.BestViableFunction(*this, Object.get()->getLocStart(), 9871 Best)) { 9872 case OR_Success: 9873 // Overload resolution succeeded; we'll build the appropriate call 9874 // below. 9875 break; 9876 9877 case OR_No_Viable_Function: 9878 if (CandidateSet.empty()) 9879 Diag(Object.get()->getSourceRange().getBegin(), diag::err_ovl_no_oper) 9880 << Object.get()->getType() << /*call*/ 1 9881 << Object.get()->getSourceRange(); 9882 else 9883 Diag(Object.get()->getSourceRange().getBegin(), 9884 diag::err_ovl_no_viable_object_call) 9885 << Object.get()->getType() << Object.get()->getSourceRange(); 9886 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9887 break; 9888 9889 case OR_Ambiguous: 9890 Diag(Object.get()->getSourceRange().getBegin(), 9891 diag::err_ovl_ambiguous_object_call) 9892 << Object.get()->getType() << Object.get()->getSourceRange(); 9893 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 9894 break; 9895 9896 case OR_Deleted: 9897 Diag(Object.get()->getSourceRange().getBegin(), 9898 diag::err_ovl_deleted_object_call) 9899 << Best->Function->isDeleted() 9900 << Object.get()->getType() 9901 << getDeletedOrUnavailableSuffix(Best->Function) 9902 << Object.get()->getSourceRange(); 9903 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9904 break; 9905 } 9906 9907 if (Best == CandidateSet.end()) 9908 return true; 9909 9910 UnbridgedCasts.restore(); 9911 9912 if (Best->Function == 0) { 9913 // Since there is no function declaration, this is one of the 9914 // surrogate candidates. Dig out the conversion function. 9915 CXXConversionDecl *Conv 9916 = cast<CXXConversionDecl>( 9917 Best->Conversions[0].UserDefined.ConversionFunction); 9918 9919 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 9920 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 9921 9922 // We selected one of the surrogate functions that converts the 9923 // object parameter to a function pointer. Perform the conversion 9924 // on the object argument, then let ActOnCallExpr finish the job. 9925 9926 // Create an implicit member expr to refer to the conversion operator. 9927 // and then call it. 9928 ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl, 9929 Conv, HadMultipleCandidates); 9930 if (Call.isInvalid()) 9931 return ExprError(); 9932 // Record usage of conversion in an implicit cast. 9933 Call = Owned(ImplicitCastExpr::Create(Context, Call.get()->getType(), 9934 CK_UserDefinedConversion, 9935 Call.get(), 0, VK_RValue)); 9936 9937 return ActOnCallExpr(S, Call.get(), LParenLoc, MultiExprArg(Args, NumArgs), 9938 RParenLoc); 9939 } 9940 9941 MarkDeclarationReferenced(LParenLoc, Best->Function); 9942 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 9943 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 9944 9945 // We found an overloaded operator(). Build a CXXOperatorCallExpr 9946 // that calls this method, using Object for the implicit object 9947 // parameter and passing along the remaining arguments. 9948 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9949 const FunctionProtoType *Proto = 9950 Method->getType()->getAs<FunctionProtoType>(); 9951 9952 unsigned NumArgsInProto = Proto->getNumArgs(); 9953 unsigned NumArgsToCheck = NumArgs; 9954 9955 // Build the full argument list for the method call (the 9956 // implicit object parameter is placed at the beginning of the 9957 // list). 9958 Expr **MethodArgs; 9959 if (NumArgs < NumArgsInProto) { 9960 NumArgsToCheck = NumArgsInProto; 9961 MethodArgs = new Expr*[NumArgsInProto + 1]; 9962 } else { 9963 MethodArgs = new Expr*[NumArgs + 1]; 9964 } 9965 MethodArgs[0] = Object.get(); 9966 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 9967 MethodArgs[ArgIdx + 1] = Args[ArgIdx]; 9968 9969 ExprResult NewFn = CreateFunctionRefExpr(*this, Method, 9970 HadMultipleCandidates); 9971 if (NewFn.isInvalid()) 9972 return true; 9973 9974 // Once we've built TheCall, all of the expressions are properly 9975 // owned. 9976 QualType ResultTy = Method->getResultType(); 9977 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9978 ResultTy = ResultTy.getNonLValueExprType(Context); 9979 9980 CXXOperatorCallExpr *TheCall = 9981 new (Context) CXXOperatorCallExpr(Context, OO_Call, NewFn.take(), 9982 MethodArgs, NumArgs + 1, 9983 ResultTy, VK, RParenLoc); 9984 delete [] MethodArgs; 9985 9986 if (CheckCallReturnType(Method->getResultType(), LParenLoc, TheCall, 9987 Method)) 9988 return true; 9989 9990 // We may have default arguments. If so, we need to allocate more 9991 // slots in the call for them. 9992 if (NumArgs < NumArgsInProto) 9993 TheCall->setNumArgs(Context, NumArgsInProto + 1); 9994 else if (NumArgs > NumArgsInProto) 9995 NumArgsToCheck = NumArgsInProto; 9996 9997 bool IsError = false; 9998 9999 // Initialize the implicit object parameter. 10000 ExprResult ObjRes = 10001 PerformObjectArgumentInitialization(Object.get(), /*Qualifier=*/0, 10002 Best->FoundDecl, Method); 10003 if (ObjRes.isInvalid()) 10004 IsError = true; 10005 else 10006 Object = move(ObjRes); 10007 TheCall->setArg(0, Object.take()); 10008 10009 // Check the argument types. 10010 for (unsigned i = 0; i != NumArgsToCheck; i++) { 10011 Expr *Arg; 10012 if (i < NumArgs) { 10013 Arg = Args[i]; 10014 10015 // Pass the argument. 10016 10017 ExprResult InputInit 10018 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 10019 Context, 10020 Method->getParamDecl(i)), 10021 SourceLocation(), Arg); 10022 10023 IsError |= InputInit.isInvalid(); 10024 Arg = InputInit.takeAs<Expr>(); 10025 } else { 10026 ExprResult DefArg 10027 = BuildCXXDefaultArgExpr(LParenLoc, Method, Method->getParamDecl(i)); 10028 if (DefArg.isInvalid()) { 10029 IsError = true; 10030 break; 10031 } 10032 10033 Arg = DefArg.takeAs<Expr>(); 10034 } 10035 10036 TheCall->setArg(i + 1, Arg); 10037 } 10038 10039 // If this is a variadic call, handle args passed through "...". 10040 if (Proto->isVariadic()) { 10041 // Promote the arguments (C99 6.5.2.2p7). 10042 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 10043 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0); 10044 IsError |= Arg.isInvalid(); 10045 TheCall->setArg(i + 1, Arg.take()); 10046 } 10047 } 10048 10049 if (IsError) return true; 10050 10051 if (CheckFunctionCall(Method, TheCall)) 10052 return true; 10053 10054 return MaybeBindToTemporary(TheCall); 10055} 10056 10057/// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator-> 10058/// (if one exists), where @c Base is an expression of class type and 10059/// @c Member is the name of the member we're trying to find. 10060ExprResult 10061Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) { 10062 assert(Base->getType()->isRecordType() && 10063 "left-hand side must have class type"); 10064 10065 if (checkPlaceholderForOverload(*this, Base)) 10066 return ExprError(); 10067 10068 SourceLocation Loc = Base->getExprLoc(); 10069 10070 // C++ [over.ref]p1: 10071 // 10072 // [...] An expression x->m is interpreted as (x.operator->())->m 10073 // for a class object x of type T if T::operator->() exists and if 10074 // the operator is selected as the best match function by the 10075 // overload resolution mechanism (13.3). 10076 DeclarationName OpName = 10077 Context.DeclarationNames.getCXXOperatorName(OO_Arrow); 10078 OverloadCandidateSet CandidateSet(Loc); 10079 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>(); 10080 10081 if (RequireCompleteType(Loc, Base->getType(), 10082 PDiag(diag::err_typecheck_incomplete_tag) 10083 << Base->getSourceRange())) 10084 return ExprError(); 10085 10086 LookupResult R(*this, OpName, OpLoc, LookupOrdinaryName); 10087 LookupQualifiedName(R, BaseRecord->getDecl()); 10088 R.suppressDiagnostics(); 10089 10090 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 10091 Oper != OperEnd; ++Oper) { 10092 AddMethodCandidate(Oper.getPair(), Base->getType(), Base->Classify(Context), 10093 0, 0, CandidateSet, /*SuppressUserConversions=*/false); 10094 } 10095 10096 bool HadMultipleCandidates = (CandidateSet.size() > 1); 10097 10098 // Perform overload resolution. 10099 OverloadCandidateSet::iterator Best; 10100 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 10101 case OR_Success: 10102 // Overload resolution succeeded; we'll build the call below. 10103 break; 10104 10105 case OR_No_Viable_Function: 10106 if (CandidateSet.empty()) 10107 Diag(OpLoc, diag::err_typecheck_member_reference_arrow) 10108 << Base->getType() << Base->getSourceRange(); 10109 else 10110 Diag(OpLoc, diag::err_ovl_no_viable_oper) 10111 << "operator->" << Base->getSourceRange(); 10112 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 10113 return ExprError(); 10114 10115 case OR_Ambiguous: 10116 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 10117 << "->" << Base->getType() << Base->getSourceRange(); 10118 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, &Base, 1); 10119 return ExprError(); 10120 10121 case OR_Deleted: 10122 Diag(OpLoc, diag::err_ovl_deleted_oper) 10123 << Best->Function->isDeleted() 10124 << "->" 10125 << getDeletedOrUnavailableSuffix(Best->Function) 10126 << Base->getSourceRange(); 10127 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 10128 return ExprError(); 10129 } 10130 10131 MarkDeclarationReferenced(OpLoc, Best->Function); 10132 CheckMemberOperatorAccess(OpLoc, Base, 0, Best->FoundDecl); 10133 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 10134 10135 // Convert the object parameter. 10136 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 10137 ExprResult BaseResult = 10138 PerformObjectArgumentInitialization(Base, /*Qualifier=*/0, 10139 Best->FoundDecl, Method); 10140 if (BaseResult.isInvalid()) 10141 return ExprError(); 10142 Base = BaseResult.take(); 10143 10144 // Build the operator call. 10145 ExprResult FnExpr = CreateFunctionRefExpr(*this, Method, 10146 HadMultipleCandidates); 10147 if (FnExpr.isInvalid()) 10148 return ExprError(); 10149 10150 QualType ResultTy = Method->getResultType(); 10151 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 10152 ResultTy = ResultTy.getNonLValueExprType(Context); 10153 CXXOperatorCallExpr *TheCall = 10154 new (Context) CXXOperatorCallExpr(Context, OO_Arrow, FnExpr.take(), 10155 &Base, 1, ResultTy, VK, OpLoc); 10156 10157 if (CheckCallReturnType(Method->getResultType(), OpLoc, TheCall, 10158 Method)) 10159 return ExprError(); 10160 10161 return MaybeBindToTemporary(TheCall); 10162} 10163 10164/// FixOverloadedFunctionReference - E is an expression that refers to 10165/// a C++ overloaded function (possibly with some parentheses and 10166/// perhaps a '&' around it). We have resolved the overloaded function 10167/// to the function declaration Fn, so patch up the expression E to 10168/// refer (possibly indirectly) to Fn. Returns the new expr. 10169Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found, 10170 FunctionDecl *Fn) { 10171 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 10172 Expr *SubExpr = FixOverloadedFunctionReference(PE->getSubExpr(), 10173 Found, Fn); 10174 if (SubExpr == PE->getSubExpr()) 10175 return PE; 10176 10177 return new (Context) ParenExpr(PE->getLParen(), PE->getRParen(), SubExpr); 10178 } 10179 10180 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 10181 Expr *SubExpr = FixOverloadedFunctionReference(ICE->getSubExpr(), 10182 Found, Fn); 10183 assert(Context.hasSameType(ICE->getSubExpr()->getType(), 10184 SubExpr->getType()) && 10185 "Implicit cast type cannot be determined from overload"); 10186 assert(ICE->path_empty() && "fixing up hierarchy conversion?"); 10187 if (SubExpr == ICE->getSubExpr()) 10188 return ICE; 10189 10190 return ImplicitCastExpr::Create(Context, ICE->getType(), 10191 ICE->getCastKind(), 10192 SubExpr, 0, 10193 ICE->getValueKind()); 10194 } 10195 10196 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) { 10197 assert(UnOp->getOpcode() == UO_AddrOf && 10198 "Can only take the address of an overloaded function"); 10199 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 10200 if (Method->isStatic()) { 10201 // Do nothing: static member functions aren't any different 10202 // from non-member functions. 10203 } else { 10204 // Fix the sub expression, which really has to be an 10205 // UnresolvedLookupExpr holding an overloaded member function 10206 // or template. 10207 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 10208 Found, Fn); 10209 if (SubExpr == UnOp->getSubExpr()) 10210 return UnOp; 10211 10212 assert(isa<DeclRefExpr>(SubExpr) 10213 && "fixed to something other than a decl ref"); 10214 assert(cast<DeclRefExpr>(SubExpr)->getQualifier() 10215 && "fixed to a member ref with no nested name qualifier"); 10216 10217 // We have taken the address of a pointer to member 10218 // function. Perform the computation here so that we get the 10219 // appropriate pointer to member type. 10220 QualType ClassType 10221 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 10222 QualType MemPtrType 10223 = Context.getMemberPointerType(Fn->getType(), ClassType.getTypePtr()); 10224 10225 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType, 10226 VK_RValue, OK_Ordinary, 10227 UnOp->getOperatorLoc()); 10228 } 10229 } 10230 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 10231 Found, Fn); 10232 if (SubExpr == UnOp->getSubExpr()) 10233 return UnOp; 10234 10235 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, 10236 Context.getPointerType(SubExpr->getType()), 10237 VK_RValue, OK_Ordinary, 10238 UnOp->getOperatorLoc()); 10239 } 10240 10241 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 10242 // FIXME: avoid copy. 10243 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 10244 if (ULE->hasExplicitTemplateArgs()) { 10245 ULE->copyTemplateArgumentsInto(TemplateArgsBuffer); 10246 TemplateArgs = &TemplateArgsBuffer; 10247 } 10248 10249 DeclRefExpr *DRE = DeclRefExpr::Create(Context, 10250 ULE->getQualifierLoc(), 10251 Fn, 10252 ULE->getNameLoc(), 10253 Fn->getType(), 10254 VK_LValue, 10255 Found.getDecl(), 10256 TemplateArgs); 10257 DRE->setHadMultipleCandidates(ULE->getNumDecls() > 1); 10258 return DRE; 10259 } 10260 10261 if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) { 10262 // FIXME: avoid copy. 10263 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 10264 if (MemExpr->hasExplicitTemplateArgs()) { 10265 MemExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 10266 TemplateArgs = &TemplateArgsBuffer; 10267 } 10268 10269 Expr *Base; 10270 10271 // If we're filling in a static method where we used to have an 10272 // implicit member access, rewrite to a simple decl ref. 10273 if (MemExpr->isImplicitAccess()) { 10274 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 10275 DeclRefExpr *DRE = DeclRefExpr::Create(Context, 10276 MemExpr->getQualifierLoc(), 10277 Fn, 10278 MemExpr->getMemberLoc(), 10279 Fn->getType(), 10280 VK_LValue, 10281 Found.getDecl(), 10282 TemplateArgs); 10283 DRE->setHadMultipleCandidates(MemExpr->getNumDecls() > 1); 10284 return DRE; 10285 } else { 10286 SourceLocation Loc = MemExpr->getMemberLoc(); 10287 if (MemExpr->getQualifier()) 10288 Loc = MemExpr->getQualifierLoc().getBeginLoc(); 10289 Base = new (Context) CXXThisExpr(Loc, 10290 MemExpr->getBaseType(), 10291 /*isImplicit=*/true); 10292 } 10293 } else 10294 Base = MemExpr->getBase(); 10295 10296 ExprValueKind valueKind; 10297 QualType type; 10298 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 10299 valueKind = VK_LValue; 10300 type = Fn->getType(); 10301 } else { 10302 valueKind = VK_RValue; 10303 type = Context.BoundMemberTy; 10304 } 10305 10306 MemberExpr *ME = MemberExpr::Create(Context, Base, 10307 MemExpr->isArrow(), 10308 MemExpr->getQualifierLoc(), 10309 Fn, 10310 Found, 10311 MemExpr->getMemberNameInfo(), 10312 TemplateArgs, 10313 type, valueKind, OK_Ordinary); 10314 ME->setHadMultipleCandidates(true); 10315 return ME; 10316 } 10317 10318 llvm_unreachable("Invalid reference to overloaded function"); 10319 return E; 10320} 10321 10322ExprResult Sema::FixOverloadedFunctionReference(ExprResult E, 10323 DeclAccessPair Found, 10324 FunctionDecl *Fn) { 10325 return Owned(FixOverloadedFunctionReference((Expr *)E.get(), Found, Fn)); 10326} 10327 10328} // end namespace clang 10329