SemaOverload.cpp revision 644be853b87cae94fcabaf309a5e482a8c291fb9
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 "Sema.h" 15#include "clang/Basic/Diagnostic.h" 16#include "clang/Lex/Preprocessor.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/CXXInheritance.h" 19#include "clang/AST/Expr.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/AST/TypeOrdering.h" 22#include "clang/Basic/PartialDiagnostic.h" 23#include "llvm/ADT/SmallPtrSet.h" 24#include "llvm/ADT/STLExtras.h" 25#include "llvm/Support/Compiler.h" 26#include <algorithm> 27#include <cstdio> 28 29namespace clang { 30 31/// GetConversionCategory - Retrieve the implicit conversion 32/// category corresponding to the given implicit conversion kind. 33ImplicitConversionCategory 34GetConversionCategory(ImplicitConversionKind Kind) { 35 static const ImplicitConversionCategory 36 Category[(int)ICK_Num_Conversion_Kinds] = { 37 ICC_Identity, 38 ICC_Lvalue_Transformation, 39 ICC_Lvalue_Transformation, 40 ICC_Lvalue_Transformation, 41 ICC_Qualification_Adjustment, 42 ICC_Promotion, 43 ICC_Promotion, 44 ICC_Promotion, 45 ICC_Conversion, 46 ICC_Conversion, 47 ICC_Conversion, 48 ICC_Conversion, 49 ICC_Conversion, 50 ICC_Conversion, 51 ICC_Conversion, 52 ICC_Conversion, 53 ICC_Conversion, 54 ICC_Conversion 55 }; 56 return Category[(int)Kind]; 57} 58 59/// GetConversionRank - Retrieve the implicit conversion rank 60/// corresponding to the given implicit conversion kind. 61ImplicitConversionRank GetConversionRank(ImplicitConversionKind Kind) { 62 static const ImplicitConversionRank 63 Rank[(int)ICK_Num_Conversion_Kinds] = { 64 ICR_Exact_Match, 65 ICR_Exact_Match, 66 ICR_Exact_Match, 67 ICR_Exact_Match, 68 ICR_Exact_Match, 69 ICR_Promotion, 70 ICR_Promotion, 71 ICR_Promotion, 72 ICR_Conversion, 73 ICR_Conversion, 74 ICR_Conversion, 75 ICR_Conversion, 76 ICR_Conversion, 77 ICR_Conversion, 78 ICR_Conversion, 79 ICR_Conversion, 80 ICR_Conversion, 81 ICR_Conversion 82 }; 83 return Rank[(int)Kind]; 84} 85 86/// GetImplicitConversionName - Return the name of this kind of 87/// implicit conversion. 88const char* GetImplicitConversionName(ImplicitConversionKind Kind) { 89 static const char* Name[(int)ICK_Num_Conversion_Kinds] = { 90 "No conversion", 91 "Lvalue-to-rvalue", 92 "Array-to-pointer", 93 "Function-to-pointer", 94 "Qualification", 95 "Integral promotion", 96 "Floating point promotion", 97 "Complex promotion", 98 "Integral conversion", 99 "Floating conversion", 100 "Complex conversion", 101 "Floating-integral conversion", 102 "Complex-real conversion", 103 "Pointer conversion", 104 "Pointer-to-member conversion", 105 "Boolean conversion", 106 "Compatible-types conversion", 107 "Derived-to-base conversion" 108 }; 109 return Name[Kind]; 110} 111 112/// StandardConversionSequence - Set the standard conversion 113/// sequence to the identity conversion. 114void StandardConversionSequence::setAsIdentityConversion() { 115 First = ICK_Identity; 116 Second = ICK_Identity; 117 Third = ICK_Identity; 118 Deprecated = false; 119 ReferenceBinding = false; 120 DirectBinding = false; 121 RRefBinding = false; 122 CopyConstructor = 0; 123} 124 125/// getRank - Retrieve the rank of this standard conversion sequence 126/// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the 127/// implicit conversions. 128ImplicitConversionRank StandardConversionSequence::getRank() const { 129 ImplicitConversionRank Rank = ICR_Exact_Match; 130 if (GetConversionRank(First) > Rank) 131 Rank = GetConversionRank(First); 132 if (GetConversionRank(Second) > Rank) 133 Rank = GetConversionRank(Second); 134 if (GetConversionRank(Third) > Rank) 135 Rank = GetConversionRank(Third); 136 return Rank; 137} 138 139/// isPointerConversionToBool - Determines whether this conversion is 140/// a conversion of a pointer or pointer-to-member to bool. This is 141/// used as part of the ranking of standard conversion sequences 142/// (C++ 13.3.3.2p4). 143bool StandardConversionSequence::isPointerConversionToBool() const { 144 QualType FromType = QualType::getFromOpaquePtr(FromTypePtr); 145 QualType ToType = QualType::getFromOpaquePtr(ToTypePtr); 146 147 // Note that FromType has not necessarily been transformed by the 148 // array-to-pointer or function-to-pointer implicit conversions, so 149 // check for their presence as well as checking whether FromType is 150 // a pointer. 151 if (ToType->isBooleanType() && 152 (FromType->isPointerType() || FromType->isBlockPointerType() || 153 First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer)) 154 return true; 155 156 return false; 157} 158 159/// isPointerConversionToVoidPointer - Determines whether this 160/// conversion is a conversion of a pointer to a void pointer. This is 161/// used as part of the ranking of standard conversion sequences (C++ 162/// 13.3.3.2p4). 163bool 164StandardConversionSequence:: 165isPointerConversionToVoidPointer(ASTContext& Context) const { 166 QualType FromType = QualType::getFromOpaquePtr(FromTypePtr); 167 QualType ToType = QualType::getFromOpaquePtr(ToTypePtr); 168 169 // Note that FromType has not necessarily been transformed by the 170 // array-to-pointer implicit conversion, so check for its presence 171 // and redo the conversion to get a pointer. 172 if (First == ICK_Array_To_Pointer) 173 FromType = Context.getArrayDecayedType(FromType); 174 175 if (Second == ICK_Pointer_Conversion) 176 if (const PointerType* ToPtrType = ToType->getAs<PointerType>()) 177 return ToPtrType->getPointeeType()->isVoidType(); 178 179 return false; 180} 181 182/// DebugPrint - Print this standard conversion sequence to standard 183/// error. Useful for debugging overloading issues. 184void StandardConversionSequence::DebugPrint() const { 185 bool PrintedSomething = false; 186 if (First != ICK_Identity) { 187 fprintf(stderr, "%s", GetImplicitConversionName(First)); 188 PrintedSomething = true; 189 } 190 191 if (Second != ICK_Identity) { 192 if (PrintedSomething) { 193 fprintf(stderr, " -> "); 194 } 195 fprintf(stderr, "%s", GetImplicitConversionName(Second)); 196 197 if (CopyConstructor) { 198 fprintf(stderr, " (by copy constructor)"); 199 } else if (DirectBinding) { 200 fprintf(stderr, " (direct reference binding)"); 201 } else if (ReferenceBinding) { 202 fprintf(stderr, " (reference binding)"); 203 } 204 PrintedSomething = true; 205 } 206 207 if (Third != ICK_Identity) { 208 if (PrintedSomething) { 209 fprintf(stderr, " -> "); 210 } 211 fprintf(stderr, "%s", GetImplicitConversionName(Third)); 212 PrintedSomething = true; 213 } 214 215 if (!PrintedSomething) { 216 fprintf(stderr, "No conversions required"); 217 } 218} 219 220/// DebugPrint - Print this user-defined conversion sequence to standard 221/// error. Useful for debugging overloading issues. 222void UserDefinedConversionSequence::DebugPrint() const { 223 if (Before.First || Before.Second || Before.Third) { 224 Before.DebugPrint(); 225 fprintf(stderr, " -> "); 226 } 227 fprintf(stderr, "'%s'", ConversionFunction->getNameAsString().c_str()); 228 if (After.First || After.Second || After.Third) { 229 fprintf(stderr, " -> "); 230 After.DebugPrint(); 231 } 232} 233 234/// DebugPrint - Print this implicit conversion sequence to standard 235/// error. Useful for debugging overloading issues. 236void ImplicitConversionSequence::DebugPrint() const { 237 switch (ConversionKind) { 238 case StandardConversion: 239 fprintf(stderr, "Standard conversion: "); 240 Standard.DebugPrint(); 241 break; 242 case UserDefinedConversion: 243 fprintf(stderr, "User-defined conversion: "); 244 UserDefined.DebugPrint(); 245 break; 246 case EllipsisConversion: 247 fprintf(stderr, "Ellipsis conversion"); 248 break; 249 case BadConversion: 250 fprintf(stderr, "Bad conversion"); 251 break; 252 } 253 254 fprintf(stderr, "\n"); 255} 256 257// IsOverload - Determine whether the given New declaration is an 258// overload of the Old declaration. This routine returns false if New 259// and Old cannot be overloaded, e.g., if they are functions with the 260// same signature (C++ 1.3.10) or if the Old declaration isn't a 261// function (or overload set). When it does return false and Old is an 262// OverloadedFunctionDecl, MatchedDecl will be set to point to the 263// FunctionDecl that New cannot be overloaded with. 264// 265// Example: Given the following input: 266// 267// void f(int, float); // #1 268// void f(int, int); // #2 269// int f(int, int); // #3 270// 271// When we process #1, there is no previous declaration of "f", 272// so IsOverload will not be used. 273// 274// When we process #2, Old is a FunctionDecl for #1. By comparing the 275// parameter types, we see that #1 and #2 are overloaded (since they 276// have different signatures), so this routine returns false; 277// MatchedDecl is unchanged. 278// 279// When we process #3, Old is an OverloadedFunctionDecl containing #1 280// and #2. We compare the signatures of #3 to #1 (they're overloaded, 281// so we do nothing) and then #3 to #2. Since the signatures of #3 and 282// #2 are identical (return types of functions are not part of the 283// signature), IsOverload returns false and MatchedDecl will be set to 284// point to the FunctionDecl for #2. 285bool 286Sema::IsOverload(FunctionDecl *New, Decl* OldD, 287 OverloadedFunctionDecl::function_iterator& MatchedDecl) { 288 if (OverloadedFunctionDecl* Ovl = dyn_cast<OverloadedFunctionDecl>(OldD)) { 289 // Is this new function an overload of every function in the 290 // overload set? 291 OverloadedFunctionDecl::function_iterator Func = Ovl->function_begin(), 292 FuncEnd = Ovl->function_end(); 293 for (; Func != FuncEnd; ++Func) { 294 if (!IsOverload(New, *Func, MatchedDecl)) { 295 MatchedDecl = Func; 296 return false; 297 } 298 } 299 300 // This function overloads every function in the overload set. 301 return true; 302 } else if (FunctionTemplateDecl *Old = dyn_cast<FunctionTemplateDecl>(OldD)) 303 return IsOverload(New, Old->getTemplatedDecl(), MatchedDecl); 304 else if (FunctionDecl* Old = dyn_cast<FunctionDecl>(OldD)) { 305 FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate(); 306 FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate(); 307 308 // C++ [temp.fct]p2: 309 // A function template can be overloaded with other function templates 310 // and with normal (non-template) functions. 311 if ((OldTemplate == 0) != (NewTemplate == 0)) 312 return true; 313 314 // Is the function New an overload of the function Old? 315 QualType OldQType = Context.getCanonicalType(Old->getType()); 316 QualType NewQType = Context.getCanonicalType(New->getType()); 317 318 // Compare the signatures (C++ 1.3.10) of the two functions to 319 // determine whether they are overloads. If we find any mismatch 320 // in the signature, they are overloads. 321 322 // If either of these functions is a K&R-style function (no 323 // prototype), then we consider them to have matching signatures. 324 if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) || 325 isa<FunctionNoProtoType>(NewQType.getTypePtr())) 326 return false; 327 328 FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType); 329 FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType); 330 331 // The signature of a function includes the types of its 332 // parameters (C++ 1.3.10), which includes the presence or absence 333 // of the ellipsis; see C++ DR 357). 334 if (OldQType != NewQType && 335 (OldType->getNumArgs() != NewType->getNumArgs() || 336 OldType->isVariadic() != NewType->isVariadic() || 337 !std::equal(OldType->arg_type_begin(), OldType->arg_type_end(), 338 NewType->arg_type_begin()))) 339 return true; 340 341 // C++ [temp.over.link]p4: 342 // The signature of a function template consists of its function 343 // signature, its return type and its template parameter list. The names 344 // of the template parameters are significant only for establishing the 345 // relationship between the template parameters and the rest of the 346 // signature. 347 // 348 // We check the return type and template parameter lists for function 349 // templates first; the remaining checks follow. 350 if (NewTemplate && 351 (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(), 352 OldTemplate->getTemplateParameters(), 353 false, false, SourceLocation()) || 354 OldType->getResultType() != NewType->getResultType())) 355 return true; 356 357 // If the function is a class member, its signature includes the 358 // cv-qualifiers (if any) on the function itself. 359 // 360 // As part of this, also check whether one of the member functions 361 // is static, in which case they are not overloads (C++ 362 // 13.1p2). While not part of the definition of the signature, 363 // this check is important to determine whether these functions 364 // can be overloaded. 365 CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 366 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 367 if (OldMethod && NewMethod && 368 !OldMethod->isStatic() && !NewMethod->isStatic() && 369 OldMethod->getTypeQualifiers() != NewMethod->getTypeQualifiers()) 370 return true; 371 372 // The signatures match; this is not an overload. 373 return false; 374 } else { 375 // (C++ 13p1): 376 // Only function declarations can be overloaded; object and type 377 // declarations cannot be overloaded. 378 return false; 379 } 380} 381 382/// TryImplicitConversion - Attempt to perform an implicit conversion 383/// from the given expression (Expr) to the given type (ToType). This 384/// function returns an implicit conversion sequence that can be used 385/// to perform the initialization. Given 386/// 387/// void f(float f); 388/// void g(int i) { f(i); } 389/// 390/// this routine would produce an implicit conversion sequence to 391/// describe the initialization of f from i, which will be a standard 392/// conversion sequence containing an lvalue-to-rvalue conversion (C++ 393/// 4.1) followed by a floating-integral conversion (C++ 4.9). 394// 395/// Note that this routine only determines how the conversion can be 396/// performed; it does not actually perform the conversion. As such, 397/// it will not produce any diagnostics if no conversion is available, 398/// but will instead return an implicit conversion sequence of kind 399/// "BadConversion". 400/// 401/// If @p SuppressUserConversions, then user-defined conversions are 402/// not permitted. 403/// If @p AllowExplicit, then explicit user-defined conversions are 404/// permitted. 405/// If @p ForceRValue, then overloading is performed as if From was an rvalue, 406/// no matter its actual lvalueness. 407/// If @p UserCast, the implicit conversion is being done for a user-specified 408/// cast. 409ImplicitConversionSequence 410Sema::TryImplicitConversion(Expr* From, QualType ToType, 411 bool SuppressUserConversions, 412 bool AllowExplicit, bool ForceRValue, 413 bool InOverloadResolution, 414 bool UserCast) { 415 ImplicitConversionSequence ICS; 416 OverloadCandidateSet Conversions; 417 OverloadingResult UserDefResult = OR_Success; 418 if (IsStandardConversion(From, ToType, InOverloadResolution, ICS.Standard)) 419 ICS.ConversionKind = ImplicitConversionSequence::StandardConversion; 420 else if (getLangOptions().CPlusPlus && 421 (UserDefResult = IsUserDefinedConversion(From, ToType, 422 ICS.UserDefined, 423 Conversions, 424 !SuppressUserConversions, AllowExplicit, 425 ForceRValue, UserCast)) == OR_Success) { 426 ICS.ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 427 // C++ [over.ics.user]p4: 428 // A conversion of an expression of class type to the same class 429 // type is given Exact Match rank, and a conversion of an 430 // expression of class type to a base class of that type is 431 // given Conversion rank, in spite of the fact that a copy 432 // constructor (i.e., a user-defined conversion function) is 433 // called for those cases. 434 if (CXXConstructorDecl *Constructor 435 = dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) { 436 QualType FromCanon 437 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 438 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 439 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 440 // Turn this into a "standard" conversion sequence, so that it 441 // gets ranked with standard conversion sequences. 442 ICS.ConversionKind = ImplicitConversionSequence::StandardConversion; 443 ICS.Standard.setAsIdentityConversion(); 444 ICS.Standard.FromTypePtr = From->getType().getAsOpaquePtr(); 445 ICS.Standard.ToTypePtr = ToType.getAsOpaquePtr(); 446 ICS.Standard.CopyConstructor = Constructor; 447 if (ToCanon != FromCanon) 448 ICS.Standard.Second = ICK_Derived_To_Base; 449 } 450 } 451 452 // C++ [over.best.ics]p4: 453 // However, when considering the argument of a user-defined 454 // conversion function that is a candidate by 13.3.1.3 when 455 // invoked for the copying of the temporary in the second step 456 // of a class copy-initialization, or by 13.3.1.4, 13.3.1.5, or 457 // 13.3.1.6 in all cases, only standard conversion sequences and 458 // ellipsis conversion sequences are allowed. 459 if (SuppressUserConversions && 460 ICS.ConversionKind == ImplicitConversionSequence::UserDefinedConversion) 461 ICS.ConversionKind = ImplicitConversionSequence::BadConversion; 462 } else { 463 ICS.ConversionKind = ImplicitConversionSequence::BadConversion; 464 if (UserDefResult == OR_Ambiguous) { 465 for (OverloadCandidateSet::iterator Cand = Conversions.begin(); 466 Cand != Conversions.end(); ++Cand) 467 if (Cand->Viable) 468 ICS.ConversionFunctionSet.push_back(Cand->Function); 469 } 470 } 471 472 return ICS; 473} 474 475/// IsStandardConversion - Determines whether there is a standard 476/// conversion sequence (C++ [conv], C++ [over.ics.scs]) from the 477/// expression From to the type ToType. Standard conversion sequences 478/// only consider non-class types; for conversions that involve class 479/// types, use TryImplicitConversion. If a conversion exists, SCS will 480/// contain the standard conversion sequence required to perform this 481/// conversion and this routine will return true. Otherwise, this 482/// routine will return false and the value of SCS is unspecified. 483bool 484Sema::IsStandardConversion(Expr* From, QualType ToType, 485 bool InOverloadResolution, 486 StandardConversionSequence &SCS) { 487 QualType FromType = From->getType(); 488 489 // Standard conversions (C++ [conv]) 490 SCS.setAsIdentityConversion(); 491 SCS.Deprecated = false; 492 SCS.IncompatibleObjC = false; 493 SCS.FromTypePtr = FromType.getAsOpaquePtr(); 494 SCS.CopyConstructor = 0; 495 496 // There are no standard conversions for class types in C++, so 497 // abort early. When overloading in C, however, we do permit 498 if (FromType->isRecordType() || ToType->isRecordType()) { 499 if (getLangOptions().CPlusPlus) 500 return false; 501 502 // When we're overloading in C, we allow, as standard conversions, 503 } 504 505 // The first conversion can be an lvalue-to-rvalue conversion, 506 // array-to-pointer conversion, or function-to-pointer conversion 507 // (C++ 4p1). 508 509 // Lvalue-to-rvalue conversion (C++ 4.1): 510 // An lvalue (3.10) of a non-function, non-array type T can be 511 // converted to an rvalue. 512 Expr::isLvalueResult argIsLvalue = From->isLvalue(Context); 513 if (argIsLvalue == Expr::LV_Valid && 514 !FromType->isFunctionType() && !FromType->isArrayType() && 515 Context.getCanonicalType(FromType) != Context.OverloadTy) { 516 SCS.First = ICK_Lvalue_To_Rvalue; 517 518 // If T is a non-class type, the type of the rvalue is the 519 // cv-unqualified version of T. Otherwise, the type of the rvalue 520 // is T (C++ 4.1p1). C++ can't get here with class types; in C, we 521 // just strip the qualifiers because they don't matter. 522 523 // FIXME: Doesn't see through to qualifiers behind a typedef! 524 FromType = FromType.getUnqualifiedType(); 525 } else if (FromType->isArrayType()) { 526 // Array-to-pointer conversion (C++ 4.2) 527 SCS.First = ICK_Array_To_Pointer; 528 529 // An lvalue or rvalue of type "array of N T" or "array of unknown 530 // bound of T" can be converted to an rvalue of type "pointer to 531 // T" (C++ 4.2p1). 532 FromType = Context.getArrayDecayedType(FromType); 533 534 if (IsStringLiteralToNonConstPointerConversion(From, ToType)) { 535 // This conversion is deprecated. (C++ D.4). 536 SCS.Deprecated = true; 537 538 // For the purpose of ranking in overload resolution 539 // (13.3.3.1.1), this conversion is considered an 540 // array-to-pointer conversion followed by a qualification 541 // conversion (4.4). (C++ 4.2p2) 542 SCS.Second = ICK_Identity; 543 SCS.Third = ICK_Qualification; 544 SCS.ToTypePtr = ToType.getAsOpaquePtr(); 545 return true; 546 } 547 } else if (FromType->isFunctionType() && argIsLvalue == Expr::LV_Valid) { 548 // Function-to-pointer conversion (C++ 4.3). 549 SCS.First = ICK_Function_To_Pointer; 550 551 // An lvalue of function type T can be converted to an rvalue of 552 // type "pointer to T." The result is a pointer to the 553 // function. (C++ 4.3p1). 554 FromType = Context.getPointerType(FromType); 555 } else if (FunctionDecl *Fn 556 = ResolveAddressOfOverloadedFunction(From, ToType, false)) { 557 // Address of overloaded function (C++ [over.over]). 558 SCS.First = ICK_Function_To_Pointer; 559 560 // We were able to resolve the address of the overloaded function, 561 // so we can convert to the type of that function. 562 FromType = Fn->getType(); 563 if (ToType->isLValueReferenceType()) 564 FromType = Context.getLValueReferenceType(FromType); 565 else if (ToType->isRValueReferenceType()) 566 FromType = Context.getRValueReferenceType(FromType); 567 else if (ToType->isMemberPointerType()) { 568 // Resolve address only succeeds if both sides are member pointers, 569 // but it doesn't have to be the same class. See DR 247. 570 // Note that this means that the type of &Derived::fn can be 571 // Ret (Base::*)(Args) if the fn overload actually found is from the 572 // base class, even if it was brought into the derived class via a 573 // using declaration. The standard isn't clear on this issue at all. 574 CXXMethodDecl *M = cast<CXXMethodDecl>(Fn); 575 FromType = Context.getMemberPointerType(FromType, 576 Context.getTypeDeclType(M->getParent()).getTypePtr()); 577 } else 578 FromType = Context.getPointerType(FromType); 579 } else { 580 // We don't require any conversions for the first step. 581 SCS.First = ICK_Identity; 582 } 583 584 // The second conversion can be an integral promotion, floating 585 // point promotion, integral conversion, floating point conversion, 586 // floating-integral conversion, pointer conversion, 587 // pointer-to-member conversion, or boolean conversion (C++ 4p1). 588 // For overloading in C, this can also be a "compatible-type" 589 // conversion. 590 bool IncompatibleObjC = false; 591 if (Context.hasSameUnqualifiedType(FromType, ToType)) { 592 // The unqualified versions of the types are the same: there's no 593 // conversion to do. 594 SCS.Second = ICK_Identity; 595 } else if (IsIntegralPromotion(From, FromType, ToType)) { 596 // Integral promotion (C++ 4.5). 597 SCS.Second = ICK_Integral_Promotion; 598 FromType = ToType.getUnqualifiedType(); 599 } else if (IsFloatingPointPromotion(FromType, ToType)) { 600 // Floating point promotion (C++ 4.6). 601 SCS.Second = ICK_Floating_Promotion; 602 FromType = ToType.getUnqualifiedType(); 603 } else if (IsComplexPromotion(FromType, ToType)) { 604 // Complex promotion (Clang extension) 605 SCS.Second = ICK_Complex_Promotion; 606 FromType = ToType.getUnqualifiedType(); 607 } else if ((FromType->isIntegralType() || FromType->isEnumeralType()) && 608 (ToType->isIntegralType() && !ToType->isEnumeralType())) { 609 // Integral conversions (C++ 4.7). 610 // FIXME: isIntegralType shouldn't be true for enums in C++. 611 SCS.Second = ICK_Integral_Conversion; 612 FromType = ToType.getUnqualifiedType(); 613 } else if (FromType->isFloatingType() && ToType->isFloatingType()) { 614 // Floating point conversions (C++ 4.8). 615 SCS.Second = ICK_Floating_Conversion; 616 FromType = ToType.getUnqualifiedType(); 617 } else if (FromType->isComplexType() && ToType->isComplexType()) { 618 // Complex conversions (C99 6.3.1.6) 619 SCS.Second = ICK_Complex_Conversion; 620 FromType = ToType.getUnqualifiedType(); 621 } else if ((FromType->isFloatingType() && 622 ToType->isIntegralType() && (!ToType->isBooleanType() && 623 !ToType->isEnumeralType())) || 624 ((FromType->isIntegralType() || FromType->isEnumeralType()) && 625 ToType->isFloatingType())) { 626 // Floating-integral conversions (C++ 4.9). 627 // FIXME: isIntegralType shouldn't be true for enums in C++. 628 SCS.Second = ICK_Floating_Integral; 629 FromType = ToType.getUnqualifiedType(); 630 } else if ((FromType->isComplexType() && ToType->isArithmeticType()) || 631 (ToType->isComplexType() && FromType->isArithmeticType())) { 632 // Complex-real conversions (C99 6.3.1.7) 633 SCS.Second = ICK_Complex_Real; 634 FromType = ToType.getUnqualifiedType(); 635 } else if (IsPointerConversion(From, FromType, ToType, InOverloadResolution, 636 FromType, IncompatibleObjC)) { 637 // Pointer conversions (C++ 4.10). 638 SCS.Second = ICK_Pointer_Conversion; 639 SCS.IncompatibleObjC = IncompatibleObjC; 640 } else if (IsMemberPointerConversion(From, FromType, ToType, 641 InOverloadResolution, FromType)) { 642 // Pointer to member conversions (4.11). 643 SCS.Second = ICK_Pointer_Member; 644 } else if (ToType->isBooleanType() && 645 (FromType->isArithmeticType() || 646 FromType->isEnumeralType() || 647 FromType->isPointerType() || 648 FromType->isBlockPointerType() || 649 FromType->isMemberPointerType() || 650 FromType->isNullPtrType())) { 651 // Boolean conversions (C++ 4.12). 652 SCS.Second = ICK_Boolean_Conversion; 653 FromType = Context.BoolTy; 654 } else if (!getLangOptions().CPlusPlus && 655 Context.typesAreCompatible(ToType, FromType)) { 656 // Compatible conversions (Clang extension for C function overloading) 657 SCS.Second = ICK_Compatible_Conversion; 658 } else { 659 // No second conversion required. 660 SCS.Second = ICK_Identity; 661 } 662 663 QualType CanonFrom; 664 QualType CanonTo; 665 // The third conversion can be a qualification conversion (C++ 4p1). 666 if (IsQualificationConversion(FromType, ToType)) { 667 SCS.Third = ICK_Qualification; 668 FromType = ToType; 669 CanonFrom = Context.getCanonicalType(FromType); 670 CanonTo = Context.getCanonicalType(ToType); 671 } else { 672 // No conversion required 673 SCS.Third = ICK_Identity; 674 675 // C++ [over.best.ics]p6: 676 // [...] Any difference in top-level cv-qualification is 677 // subsumed by the initialization itself and does not constitute 678 // a conversion. [...] 679 CanonFrom = Context.getCanonicalType(FromType); 680 CanonTo = Context.getCanonicalType(ToType); 681 if (CanonFrom.getUnqualifiedType() == CanonTo.getUnqualifiedType() && 682 CanonFrom.getCVRQualifiers() != CanonTo.getCVRQualifiers()) { 683 FromType = ToType; 684 CanonFrom = CanonTo; 685 } 686 } 687 688 // If we have not converted the argument type to the parameter type, 689 // this is a bad conversion sequence. 690 if (CanonFrom != CanonTo) 691 return false; 692 693 SCS.ToTypePtr = FromType.getAsOpaquePtr(); 694 return true; 695} 696 697/// IsIntegralPromotion - Determines whether the conversion from the 698/// expression From (whose potentially-adjusted type is FromType) to 699/// ToType is an integral promotion (C++ 4.5). If so, returns true and 700/// sets PromotedType to the promoted type. 701bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) { 702 const BuiltinType *To = ToType->getAs<BuiltinType>(); 703 // All integers are built-in. 704 if (!To) { 705 return false; 706 } 707 708 // An rvalue of type char, signed char, unsigned char, short int, or 709 // unsigned short int can be converted to an rvalue of type int if 710 // int can represent all the values of the source type; otherwise, 711 // the source rvalue can be converted to an rvalue of type unsigned 712 // int (C++ 4.5p1). 713 if (FromType->isPromotableIntegerType() && !FromType->isBooleanType()) { 714 if (// We can promote any signed, promotable integer type to an int 715 (FromType->isSignedIntegerType() || 716 // We can promote any unsigned integer type whose size is 717 // less than int to an int. 718 (!FromType->isSignedIntegerType() && 719 Context.getTypeSize(FromType) < Context.getTypeSize(ToType)))) { 720 return To->getKind() == BuiltinType::Int; 721 } 722 723 return To->getKind() == BuiltinType::UInt; 724 } 725 726 // An rvalue of type wchar_t (3.9.1) or an enumeration type (7.2) 727 // can be converted to an rvalue of the first of the following types 728 // that can represent all the values of its underlying type: int, 729 // unsigned int, long, or unsigned long (C++ 4.5p2). 730 if ((FromType->isEnumeralType() || FromType->isWideCharType()) 731 && ToType->isIntegerType()) { 732 // Determine whether the type we're converting from is signed or 733 // unsigned. 734 bool FromIsSigned; 735 uint64_t FromSize = Context.getTypeSize(FromType); 736 if (const EnumType *FromEnumType = FromType->getAs<EnumType>()) { 737 QualType UnderlyingType = FromEnumType->getDecl()->getIntegerType(); 738 FromIsSigned = UnderlyingType->isSignedIntegerType(); 739 } else { 740 // FIXME: Is wchar_t signed or unsigned? We assume it's signed for now. 741 FromIsSigned = true; 742 } 743 744 // The types we'll try to promote to, in the appropriate 745 // order. Try each of these types. 746 QualType PromoteTypes[6] = { 747 Context.IntTy, Context.UnsignedIntTy, 748 Context.LongTy, Context.UnsignedLongTy , 749 Context.LongLongTy, Context.UnsignedLongLongTy 750 }; 751 for (int Idx = 0; Idx < 6; ++Idx) { 752 uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]); 753 if (FromSize < ToSize || 754 (FromSize == ToSize && 755 FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) { 756 // We found the type that we can promote to. If this is the 757 // type we wanted, we have a promotion. Otherwise, no 758 // promotion. 759 return Context.getCanonicalType(ToType).getUnqualifiedType() 760 == Context.getCanonicalType(PromoteTypes[Idx]).getUnqualifiedType(); 761 } 762 } 763 } 764 765 // An rvalue for an integral bit-field (9.6) can be converted to an 766 // rvalue of type int if int can represent all the values of the 767 // bit-field; otherwise, it can be converted to unsigned int if 768 // unsigned int can represent all the values of the bit-field. If 769 // the bit-field is larger yet, no integral promotion applies to 770 // it. If the bit-field has an enumerated type, it is treated as any 771 // other value of that type for promotion purposes (C++ 4.5p3). 772 // FIXME: We should delay checking of bit-fields until we actually perform the 773 // conversion. 774 using llvm::APSInt; 775 if (From) 776 if (FieldDecl *MemberDecl = From->getBitField()) { 777 APSInt BitWidth; 778 if (FromType->isIntegralType() && !FromType->isEnumeralType() && 779 MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) { 780 APSInt ToSize(BitWidth.getBitWidth(), BitWidth.isUnsigned()); 781 ToSize = Context.getTypeSize(ToType); 782 783 // Are we promoting to an int from a bitfield that fits in an int? 784 if (BitWidth < ToSize || 785 (FromType->isSignedIntegerType() && BitWidth <= ToSize)) { 786 return To->getKind() == BuiltinType::Int; 787 } 788 789 // Are we promoting to an unsigned int from an unsigned bitfield 790 // that fits into an unsigned int? 791 if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize) { 792 return To->getKind() == BuiltinType::UInt; 793 } 794 795 return false; 796 } 797 } 798 799 // An rvalue of type bool can be converted to an rvalue of type int, 800 // with false becoming zero and true becoming one (C++ 4.5p4). 801 if (FromType->isBooleanType() && To->getKind() == BuiltinType::Int) { 802 return true; 803 } 804 805 return false; 806} 807 808/// IsFloatingPointPromotion - Determines whether the conversion from 809/// FromType to ToType is a floating point promotion (C++ 4.6). If so, 810/// returns true and sets PromotedType to the promoted type. 811bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType) { 812 /// An rvalue of type float can be converted to an rvalue of type 813 /// double. (C++ 4.6p1). 814 if (const BuiltinType *FromBuiltin = FromType->getAs<BuiltinType>()) 815 if (const BuiltinType *ToBuiltin = ToType->getAs<BuiltinType>()) { 816 if (FromBuiltin->getKind() == BuiltinType::Float && 817 ToBuiltin->getKind() == BuiltinType::Double) 818 return true; 819 820 // C99 6.3.1.5p1: 821 // When a float is promoted to double or long double, or a 822 // double is promoted to long double [...]. 823 if (!getLangOptions().CPlusPlus && 824 (FromBuiltin->getKind() == BuiltinType::Float || 825 FromBuiltin->getKind() == BuiltinType::Double) && 826 (ToBuiltin->getKind() == BuiltinType::LongDouble)) 827 return true; 828 } 829 830 return false; 831} 832 833/// \brief Determine if a conversion is a complex promotion. 834/// 835/// A complex promotion is defined as a complex -> complex conversion 836/// where the conversion between the underlying real types is a 837/// floating-point or integral promotion. 838bool Sema::IsComplexPromotion(QualType FromType, QualType ToType) { 839 const ComplexType *FromComplex = FromType->getAs<ComplexType>(); 840 if (!FromComplex) 841 return false; 842 843 const ComplexType *ToComplex = ToType->getAs<ComplexType>(); 844 if (!ToComplex) 845 return false; 846 847 return IsFloatingPointPromotion(FromComplex->getElementType(), 848 ToComplex->getElementType()) || 849 IsIntegralPromotion(0, FromComplex->getElementType(), 850 ToComplex->getElementType()); 851} 852 853/// BuildSimilarlyQualifiedPointerType - In a pointer conversion from 854/// the pointer type FromPtr to a pointer to type ToPointee, with the 855/// same type qualifiers as FromPtr has on its pointee type. ToType, 856/// if non-empty, will be a pointer to ToType that may or may not have 857/// the right set of qualifiers on its pointee. 858static QualType 859BuildSimilarlyQualifiedPointerType(const PointerType *FromPtr, 860 QualType ToPointee, QualType ToType, 861 ASTContext &Context) { 862 QualType CanonFromPointee = Context.getCanonicalType(FromPtr->getPointeeType()); 863 QualType CanonToPointee = Context.getCanonicalType(ToPointee); 864 Qualifiers Quals = CanonFromPointee.getQualifiers(); 865 866 // Exact qualifier match -> return the pointer type we're converting to. 867 if (CanonToPointee.getQualifiers() == Quals) { 868 // ToType is exactly what we need. Return it. 869 if (!ToType.isNull()) 870 return ToType; 871 872 // Build a pointer to ToPointee. It has the right qualifiers 873 // already. 874 return Context.getPointerType(ToPointee); 875 } 876 877 // Just build a canonical type that has the right qualifiers. 878 return Context.getPointerType( 879 Context.getQualifiedType(CanonToPointee.getUnqualifiedType(), Quals)); 880} 881 882static bool isNullPointerConstantForConversion(Expr *Expr, 883 bool InOverloadResolution, 884 ASTContext &Context) { 885 // Handle value-dependent integral null pointer constants correctly. 886 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903 887 if (Expr->isValueDependent() && !Expr->isTypeDependent() && 888 Expr->getType()->isIntegralType()) 889 return !InOverloadResolution; 890 891 return Expr->isNullPointerConstant(Context, 892 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 893 : Expr::NPC_ValueDependentIsNull); 894} 895 896/// IsPointerConversion - Determines whether the conversion of the 897/// expression From, which has the (possibly adjusted) type FromType, 898/// can be converted to the type ToType via a pointer conversion (C++ 899/// 4.10). If so, returns true and places the converted type (that 900/// might differ from ToType in its cv-qualifiers at some level) into 901/// ConvertedType. 902/// 903/// This routine also supports conversions to and from block pointers 904/// and conversions with Objective-C's 'id', 'id<protocols...>', and 905/// pointers to interfaces. FIXME: Once we've determined the 906/// appropriate overloading rules for Objective-C, we may want to 907/// split the Objective-C checks into a different routine; however, 908/// GCC seems to consider all of these conversions to be pointer 909/// conversions, so for now they live here. IncompatibleObjC will be 910/// set if the conversion is an allowed Objective-C conversion that 911/// should result in a warning. 912bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType, 913 bool InOverloadResolution, 914 QualType& ConvertedType, 915 bool &IncompatibleObjC) { 916 IncompatibleObjC = false; 917 if (isObjCPointerConversion(FromType, ToType, ConvertedType, IncompatibleObjC)) 918 return true; 919 920 // Conversion from a null pointer constant to any Objective-C pointer type. 921 if (ToType->isObjCObjectPointerType() && 922 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 923 ConvertedType = ToType; 924 return true; 925 } 926 927 // Blocks: Block pointers can be converted to void*. 928 if (FromType->isBlockPointerType() && ToType->isPointerType() && 929 ToType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 930 ConvertedType = ToType; 931 return true; 932 } 933 // Blocks: A null pointer constant can be converted to a block 934 // pointer type. 935 if (ToType->isBlockPointerType() && 936 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 937 ConvertedType = ToType; 938 return true; 939 } 940 941 // If the left-hand-side is nullptr_t, the right side can be a null 942 // pointer constant. 943 if (ToType->isNullPtrType() && 944 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 945 ConvertedType = ToType; 946 return true; 947 } 948 949 const PointerType* ToTypePtr = ToType->getAs<PointerType>(); 950 if (!ToTypePtr) 951 return false; 952 953 // A null pointer constant can be converted to a pointer type (C++ 4.10p1). 954 if (isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 955 ConvertedType = ToType; 956 return true; 957 } 958 959 // Beyond this point, both types need to be pointers. 960 const PointerType *FromTypePtr = FromType->getAs<PointerType>(); 961 if (!FromTypePtr) 962 return false; 963 964 QualType FromPointeeType = FromTypePtr->getPointeeType(); 965 QualType ToPointeeType = ToTypePtr->getPointeeType(); 966 967 // An rvalue of type "pointer to cv T," where T is an object type, 968 // can be converted to an rvalue of type "pointer to cv void" (C++ 969 // 4.10p2). 970 if (FromPointeeType->isObjectType() && ToPointeeType->isVoidType()) { 971 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 972 ToPointeeType, 973 ToType, Context); 974 return true; 975 } 976 977 // When we're overloading in C, we allow a special kind of pointer 978 // conversion for compatible-but-not-identical pointee types. 979 if (!getLangOptions().CPlusPlus && 980 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) { 981 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 982 ToPointeeType, 983 ToType, Context); 984 return true; 985 } 986 987 // C++ [conv.ptr]p3: 988 // 989 // An rvalue of type "pointer to cv D," where D is a class type, 990 // can be converted to an rvalue of type "pointer to cv B," where 991 // B is a base class (clause 10) of D. If B is an inaccessible 992 // (clause 11) or ambiguous (10.2) base class of D, a program that 993 // necessitates this conversion is ill-formed. The result of the 994 // conversion is a pointer to the base class sub-object of the 995 // derived class object. The null pointer value is converted to 996 // the null pointer value of the destination type. 997 // 998 // Note that we do not check for ambiguity or inaccessibility 999 // here. That is handled by CheckPointerConversion. 1000 if (getLangOptions().CPlusPlus && 1001 FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 1002 IsDerivedFrom(FromPointeeType, ToPointeeType)) { 1003 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1004 ToPointeeType, 1005 ToType, Context); 1006 return true; 1007 } 1008 1009 return false; 1010} 1011 1012/// isObjCPointerConversion - Determines whether this is an 1013/// Objective-C pointer conversion. Subroutine of IsPointerConversion, 1014/// with the same arguments and return values. 1015bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType, 1016 QualType& ConvertedType, 1017 bool &IncompatibleObjC) { 1018 if (!getLangOptions().ObjC1) 1019 return false; 1020 1021 // First, we handle all conversions on ObjC object pointer types. 1022 const ObjCObjectPointerType* ToObjCPtr = ToType->getAs<ObjCObjectPointerType>(); 1023 const ObjCObjectPointerType *FromObjCPtr = 1024 FromType->getAs<ObjCObjectPointerType>(); 1025 1026 if (ToObjCPtr && FromObjCPtr) { 1027 // Objective C++: We're able to convert between "id" or "Class" and a 1028 // pointer to any interface (in both directions). 1029 if (ToObjCPtr->isObjCBuiltinType() && FromObjCPtr->isObjCBuiltinType()) { 1030 ConvertedType = ToType; 1031 return true; 1032 } 1033 // Conversions with Objective-C's id<...>. 1034 if ((FromObjCPtr->isObjCQualifiedIdType() || 1035 ToObjCPtr->isObjCQualifiedIdType()) && 1036 Context.ObjCQualifiedIdTypesAreCompatible(ToType, FromType, 1037 /*compare=*/false)) { 1038 ConvertedType = ToType; 1039 return true; 1040 } 1041 // Objective C++: We're able to convert from a pointer to an 1042 // interface to a pointer to a different interface. 1043 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) { 1044 ConvertedType = ToType; 1045 return true; 1046 } 1047 1048 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) { 1049 // Okay: this is some kind of implicit downcast of Objective-C 1050 // interfaces, which is permitted. However, we're going to 1051 // complain about it. 1052 IncompatibleObjC = true; 1053 ConvertedType = FromType; 1054 return true; 1055 } 1056 } 1057 // Beyond this point, both types need to be C pointers or block pointers. 1058 QualType ToPointeeType; 1059 if (const PointerType *ToCPtr = ToType->getAs<PointerType>()) 1060 ToPointeeType = ToCPtr->getPointeeType(); 1061 else if (const BlockPointerType *ToBlockPtr = ToType->getAs<BlockPointerType>()) 1062 ToPointeeType = ToBlockPtr->getPointeeType(); 1063 else 1064 return false; 1065 1066 QualType FromPointeeType; 1067 if (const PointerType *FromCPtr = FromType->getAs<PointerType>()) 1068 FromPointeeType = FromCPtr->getPointeeType(); 1069 else if (const BlockPointerType *FromBlockPtr = FromType->getAs<BlockPointerType>()) 1070 FromPointeeType = FromBlockPtr->getPointeeType(); 1071 else 1072 return false; 1073 1074 // If we have pointers to pointers, recursively check whether this 1075 // is an Objective-C conversion. 1076 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() && 1077 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1078 IncompatibleObjC)) { 1079 // We always complain about this conversion. 1080 IncompatibleObjC = true; 1081 ConvertedType = ToType; 1082 return true; 1083 } 1084 // If we have pointers to functions or blocks, check whether the only 1085 // differences in the argument and result types are in Objective-C 1086 // pointer conversions. If so, we permit the conversion (but 1087 // complain about it). 1088 const FunctionProtoType *FromFunctionType 1089 = FromPointeeType->getAs<FunctionProtoType>(); 1090 const FunctionProtoType *ToFunctionType 1091 = ToPointeeType->getAs<FunctionProtoType>(); 1092 if (FromFunctionType && ToFunctionType) { 1093 // If the function types are exactly the same, this isn't an 1094 // Objective-C pointer conversion. 1095 if (Context.getCanonicalType(FromPointeeType) 1096 == Context.getCanonicalType(ToPointeeType)) 1097 return false; 1098 1099 // Perform the quick checks that will tell us whether these 1100 // function types are obviously different. 1101 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 1102 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() || 1103 FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals()) 1104 return false; 1105 1106 bool HasObjCConversion = false; 1107 if (Context.getCanonicalType(FromFunctionType->getResultType()) 1108 == Context.getCanonicalType(ToFunctionType->getResultType())) { 1109 // Okay, the types match exactly. Nothing to do. 1110 } else if (isObjCPointerConversion(FromFunctionType->getResultType(), 1111 ToFunctionType->getResultType(), 1112 ConvertedType, IncompatibleObjC)) { 1113 // Okay, we have an Objective-C pointer conversion. 1114 HasObjCConversion = true; 1115 } else { 1116 // Function types are too different. Abort. 1117 return false; 1118 } 1119 1120 // Check argument types. 1121 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 1122 ArgIdx != NumArgs; ++ArgIdx) { 1123 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 1124 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 1125 if (Context.getCanonicalType(FromArgType) 1126 == Context.getCanonicalType(ToArgType)) { 1127 // Okay, the types match exactly. Nothing to do. 1128 } else if (isObjCPointerConversion(FromArgType, ToArgType, 1129 ConvertedType, IncompatibleObjC)) { 1130 // Okay, we have an Objective-C pointer conversion. 1131 HasObjCConversion = true; 1132 } else { 1133 // Argument types are too different. Abort. 1134 return false; 1135 } 1136 } 1137 1138 if (HasObjCConversion) { 1139 // We had an Objective-C conversion. Allow this pointer 1140 // conversion, but complain about it. 1141 ConvertedType = ToType; 1142 IncompatibleObjC = true; 1143 return true; 1144 } 1145 } 1146 1147 return false; 1148} 1149 1150/// CheckPointerConversion - Check the pointer conversion from the 1151/// expression From to the type ToType. This routine checks for 1152/// ambiguous or inaccessible derived-to-base pointer 1153/// conversions for which IsPointerConversion has already returned 1154/// true. It returns true and produces a diagnostic if there was an 1155/// error, or returns false otherwise. 1156bool Sema::CheckPointerConversion(Expr *From, QualType ToType, 1157 CastExpr::CastKind &Kind) { 1158 QualType FromType = From->getType(); 1159 1160 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) 1161 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) { 1162 QualType FromPointeeType = FromPtrType->getPointeeType(), 1163 ToPointeeType = ToPtrType->getPointeeType(); 1164 1165 if (FromPointeeType->isRecordType() && 1166 ToPointeeType->isRecordType()) { 1167 // We must have a derived-to-base conversion. Check an 1168 // ambiguous or inaccessible conversion. 1169 if (CheckDerivedToBaseConversion(FromPointeeType, ToPointeeType, 1170 From->getExprLoc(), 1171 From->getSourceRange())) 1172 return true; 1173 1174 // The conversion was successful. 1175 Kind = CastExpr::CK_DerivedToBase; 1176 } 1177 } 1178 if (const ObjCObjectPointerType *FromPtrType = 1179 FromType->getAs<ObjCObjectPointerType>()) 1180 if (const ObjCObjectPointerType *ToPtrType = 1181 ToType->getAs<ObjCObjectPointerType>()) { 1182 // Objective-C++ conversions are always okay. 1183 // FIXME: We should have a different class of conversions for the 1184 // Objective-C++ implicit conversions. 1185 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType()) 1186 return false; 1187 1188 } 1189 return false; 1190} 1191 1192/// IsMemberPointerConversion - Determines whether the conversion of the 1193/// expression From, which has the (possibly adjusted) type FromType, can be 1194/// converted to the type ToType via a member pointer conversion (C++ 4.11). 1195/// If so, returns true and places the converted type (that might differ from 1196/// ToType in its cv-qualifiers at some level) into ConvertedType. 1197bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType, 1198 QualType ToType, 1199 bool InOverloadResolution, 1200 QualType &ConvertedType) { 1201 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>(); 1202 if (!ToTypePtr) 1203 return false; 1204 1205 // A null pointer constant can be converted to a member pointer (C++ 4.11p1) 1206 if (From->isNullPointerConstant(Context, 1207 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 1208 : Expr::NPC_ValueDependentIsNull)) { 1209 ConvertedType = ToType; 1210 return true; 1211 } 1212 1213 // Otherwise, both types have to be member pointers. 1214 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>(); 1215 if (!FromTypePtr) 1216 return false; 1217 1218 // A pointer to member of B can be converted to a pointer to member of D, 1219 // where D is derived from B (C++ 4.11p2). 1220 QualType FromClass(FromTypePtr->getClass(), 0); 1221 QualType ToClass(ToTypePtr->getClass(), 0); 1222 // FIXME: What happens when these are dependent? Is this function even called? 1223 1224 if (IsDerivedFrom(ToClass, FromClass)) { 1225 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(), 1226 ToClass.getTypePtr()); 1227 return true; 1228 } 1229 1230 return false; 1231} 1232 1233/// CheckMemberPointerConversion - Check the member pointer conversion from the 1234/// expression From to the type ToType. This routine checks for ambiguous or 1235/// virtual (FIXME: or inaccessible) base-to-derived member pointer conversions 1236/// for which IsMemberPointerConversion has already returned true. It returns 1237/// true and produces a diagnostic if there was an error, or returns false 1238/// otherwise. 1239bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType, 1240 CastExpr::CastKind &Kind) { 1241 QualType FromType = From->getType(); 1242 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>(); 1243 if (!FromPtrType) { 1244 // This must be a null pointer to member pointer conversion 1245 assert(From->isNullPointerConstant(Context, 1246 Expr::NPC_ValueDependentIsNull) && 1247 "Expr must be null pointer constant!"); 1248 Kind = CastExpr::CK_NullToMemberPointer; 1249 return false; 1250 } 1251 1252 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>(); 1253 assert(ToPtrType && "No member pointer cast has a target type " 1254 "that is not a member pointer."); 1255 1256 QualType FromClass = QualType(FromPtrType->getClass(), 0); 1257 QualType ToClass = QualType(ToPtrType->getClass(), 0); 1258 1259 // FIXME: What about dependent types? 1260 assert(FromClass->isRecordType() && "Pointer into non-class."); 1261 assert(ToClass->isRecordType() && "Pointer into non-class."); 1262 1263 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/false, 1264 /*DetectVirtual=*/true); 1265 bool DerivationOkay = IsDerivedFrom(ToClass, FromClass, Paths); 1266 assert(DerivationOkay && 1267 "Should not have been called if derivation isn't OK."); 1268 (void)DerivationOkay; 1269 1270 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass). 1271 getUnqualifiedType())) { 1272 // Derivation is ambiguous. Redo the check to find the exact paths. 1273 Paths.clear(); 1274 Paths.setRecordingPaths(true); 1275 bool StillOkay = IsDerivedFrom(ToClass, FromClass, Paths); 1276 assert(StillOkay && "Derivation changed due to quantum fluctuation."); 1277 (void)StillOkay; 1278 1279 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths); 1280 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv) 1281 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange(); 1282 return true; 1283 } 1284 1285 if (const RecordType *VBase = Paths.getDetectedVirtual()) { 1286 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual) 1287 << FromClass << ToClass << QualType(VBase, 0) 1288 << From->getSourceRange(); 1289 return true; 1290 } 1291 1292 // Must be a base to derived member conversion. 1293 Kind = CastExpr::CK_BaseToDerivedMemberPointer; 1294 return false; 1295} 1296 1297/// IsQualificationConversion - Determines whether the conversion from 1298/// an rvalue of type FromType to ToType is a qualification conversion 1299/// (C++ 4.4). 1300bool 1301Sema::IsQualificationConversion(QualType FromType, QualType ToType) { 1302 FromType = Context.getCanonicalType(FromType); 1303 ToType = Context.getCanonicalType(ToType); 1304 1305 // If FromType and ToType are the same type, this is not a 1306 // qualification conversion. 1307 if (FromType == ToType) 1308 return false; 1309 1310 // (C++ 4.4p4): 1311 // A conversion can add cv-qualifiers at levels other than the first 1312 // in multi-level pointers, subject to the following rules: [...] 1313 bool PreviousToQualsIncludeConst = true; 1314 bool UnwrappedAnyPointer = false; 1315 while (UnwrapSimilarPointerTypes(FromType, ToType)) { 1316 // Within each iteration of the loop, we check the qualifiers to 1317 // determine if this still looks like a qualification 1318 // conversion. Then, if all is well, we unwrap one more level of 1319 // pointers or pointers-to-members and do it all again 1320 // until there are no more pointers or pointers-to-members left to 1321 // unwrap. 1322 UnwrappedAnyPointer = true; 1323 1324 // -- for every j > 0, if const is in cv 1,j then const is in cv 1325 // 2,j, and similarly for volatile. 1326 if (!ToType.isAtLeastAsQualifiedAs(FromType)) 1327 return false; 1328 1329 // -- if the cv 1,j and cv 2,j are different, then const is in 1330 // every cv for 0 < k < j. 1331 if (FromType.getCVRQualifiers() != ToType.getCVRQualifiers() 1332 && !PreviousToQualsIncludeConst) 1333 return false; 1334 1335 // Keep track of whether all prior cv-qualifiers in the "to" type 1336 // include const. 1337 PreviousToQualsIncludeConst 1338 = PreviousToQualsIncludeConst && ToType.isConstQualified(); 1339 } 1340 1341 // We are left with FromType and ToType being the pointee types 1342 // after unwrapping the original FromType and ToType the same number 1343 // of types. If we unwrapped any pointers, and if FromType and 1344 // ToType have the same unqualified type (since we checked 1345 // qualifiers above), then this is a qualification conversion. 1346 return UnwrappedAnyPointer && 1347 FromType.getUnqualifiedType() == ToType.getUnqualifiedType(); 1348} 1349 1350/// \brief Given a function template or function, extract the function template 1351/// declaration (if any) and the underlying function declaration. 1352template<typename T> 1353static void GetFunctionAndTemplate(AnyFunctionDecl Orig, T *&Function, 1354 FunctionTemplateDecl *&FunctionTemplate) { 1355 FunctionTemplate = dyn_cast<FunctionTemplateDecl>(Orig); 1356 if (FunctionTemplate) 1357 Function = cast<T>(FunctionTemplate->getTemplatedDecl()); 1358 else 1359 Function = cast<T>(Orig); 1360} 1361 1362/// Determines whether there is a user-defined conversion sequence 1363/// (C++ [over.ics.user]) that converts expression From to the type 1364/// ToType. If such a conversion exists, User will contain the 1365/// user-defined conversion sequence that performs such a conversion 1366/// and this routine will return true. Otherwise, this routine returns 1367/// false and User is unspecified. 1368/// 1369/// \param AllowConversionFunctions true if the conversion should 1370/// consider conversion functions at all. If false, only constructors 1371/// will be considered. 1372/// 1373/// \param AllowExplicit true if the conversion should consider C++0x 1374/// "explicit" conversion functions as well as non-explicit conversion 1375/// functions (C++0x [class.conv.fct]p2). 1376/// 1377/// \param ForceRValue true if the expression should be treated as an rvalue 1378/// for overload resolution. 1379/// \param UserCast true if looking for user defined conversion for a static 1380/// cast. 1381Sema::OverloadingResult Sema::IsUserDefinedConversion( 1382 Expr *From, QualType ToType, 1383 UserDefinedConversionSequence& User, 1384 OverloadCandidateSet& CandidateSet, 1385 bool AllowConversionFunctions, 1386 bool AllowExplicit, bool ForceRValue, 1387 bool UserCast) { 1388 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) { 1389 if (CXXRecordDecl *ToRecordDecl 1390 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) { 1391 // C++ [over.match.ctor]p1: 1392 // When objects of class type are direct-initialized (8.5), or 1393 // copy-initialized from an expression of the same or a 1394 // derived class type (8.5), overload resolution selects the 1395 // constructor. [...] For copy-initialization, the candidate 1396 // functions are all the converting constructors (12.3.1) of 1397 // that class. The argument list is the expression-list within 1398 // the parentheses of the initializer. 1399 DeclarationName ConstructorName 1400 = Context.DeclarationNames.getCXXConstructorName( 1401 Context.getCanonicalType(ToType).getUnqualifiedType()); 1402 DeclContext::lookup_iterator Con, ConEnd; 1403 for (llvm::tie(Con, ConEnd) 1404 = ToRecordDecl->lookup(ConstructorName); 1405 Con != ConEnd; ++Con) { 1406 // Find the constructor (which may be a template). 1407 CXXConstructorDecl *Constructor = 0; 1408 FunctionTemplateDecl *ConstructorTmpl 1409 = dyn_cast<FunctionTemplateDecl>(*Con); 1410 if (ConstructorTmpl) 1411 Constructor 1412 = cast<CXXConstructorDecl>(ConstructorTmpl->getTemplatedDecl()); 1413 else 1414 Constructor = cast<CXXConstructorDecl>(*Con); 1415 1416 if (!Constructor->isInvalidDecl() && 1417 Constructor->isConvertingConstructor(AllowExplicit)) { 1418 if (ConstructorTmpl) 1419 AddTemplateOverloadCandidate(ConstructorTmpl, false, 0, 0, &From, 1420 1, CandidateSet, 1421 /*SuppressUserConversions=*/!UserCast, 1422 ForceRValue); 1423 else 1424 // Allow one user-defined conversion when user specifies a 1425 // From->ToType conversion via an static cast (c-style, etc). 1426 AddOverloadCandidate(Constructor, &From, 1, CandidateSet, 1427 /*SuppressUserConversions=*/!UserCast, 1428 ForceRValue); 1429 } 1430 } 1431 } 1432 } 1433 1434 if (!AllowConversionFunctions) { 1435 // Don't allow any conversion functions to enter the overload set. 1436 } else if (RequireCompleteType(From->getLocStart(), From->getType(), 1437 PDiag(0) 1438 << From->getSourceRange())) { 1439 // No conversion functions from incomplete types. 1440 } else if (const RecordType *FromRecordType 1441 = From->getType()->getAs<RecordType>()) { 1442 if (CXXRecordDecl *FromRecordDecl 1443 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) { 1444 // Add all of the conversion functions as candidates. 1445 OverloadedFunctionDecl *Conversions 1446 = FromRecordDecl->getVisibleConversionFunctions(); 1447 for (OverloadedFunctionDecl::function_iterator Func 1448 = Conversions->function_begin(); 1449 Func != Conversions->function_end(); ++Func) { 1450 CXXConversionDecl *Conv; 1451 FunctionTemplateDecl *ConvTemplate; 1452 GetFunctionAndTemplate(*Func, Conv, ConvTemplate); 1453 if (ConvTemplate) 1454 Conv = dyn_cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 1455 else 1456 Conv = dyn_cast<CXXConversionDecl>(*Func); 1457 1458 if (AllowExplicit || !Conv->isExplicit()) { 1459 if (ConvTemplate) 1460 AddTemplateConversionCandidate(ConvTemplate, From, ToType, 1461 CandidateSet); 1462 else 1463 AddConversionCandidate(Conv, From, ToType, CandidateSet); 1464 } 1465 } 1466 } 1467 } 1468 1469 OverloadCandidateSet::iterator Best; 1470 switch (BestViableFunction(CandidateSet, From->getLocStart(), Best)) { 1471 case OR_Success: 1472 // Record the standard conversion we used and the conversion function. 1473 if (CXXConstructorDecl *Constructor 1474 = dyn_cast<CXXConstructorDecl>(Best->Function)) { 1475 // C++ [over.ics.user]p1: 1476 // If the user-defined conversion is specified by a 1477 // constructor (12.3.1), the initial standard conversion 1478 // sequence converts the source type to the type required by 1479 // the argument of the constructor. 1480 // 1481 // FIXME: What about ellipsis conversions? 1482 QualType ThisType = Constructor->getThisType(Context); 1483 User.Before = Best->Conversions[0].Standard; 1484 User.ConversionFunction = Constructor; 1485 User.After.setAsIdentityConversion(); 1486 User.After.FromTypePtr 1487 = ThisType->getAs<PointerType>()->getPointeeType().getAsOpaquePtr(); 1488 User.After.ToTypePtr = ToType.getAsOpaquePtr(); 1489 return OR_Success; 1490 } else if (CXXConversionDecl *Conversion 1491 = dyn_cast<CXXConversionDecl>(Best->Function)) { 1492 // C++ [over.ics.user]p1: 1493 // 1494 // [...] If the user-defined conversion is specified by a 1495 // conversion function (12.3.2), the initial standard 1496 // conversion sequence converts the source type to the 1497 // implicit object parameter of the conversion function. 1498 User.Before = Best->Conversions[0].Standard; 1499 User.ConversionFunction = Conversion; 1500 1501 // C++ [over.ics.user]p2: 1502 // The second standard conversion sequence converts the 1503 // result of the user-defined conversion to the target type 1504 // for the sequence. Since an implicit conversion sequence 1505 // is an initialization, the special rules for 1506 // initialization by user-defined conversion apply when 1507 // selecting the best user-defined conversion for a 1508 // user-defined conversion sequence (see 13.3.3 and 1509 // 13.3.3.1). 1510 User.After = Best->FinalConversion; 1511 return OR_Success; 1512 } else { 1513 assert(false && "Not a constructor or conversion function?"); 1514 return OR_No_Viable_Function; 1515 } 1516 1517 case OR_No_Viable_Function: 1518 return OR_No_Viable_Function; 1519 case OR_Deleted: 1520 // No conversion here! We're done. 1521 return OR_Deleted; 1522 1523 case OR_Ambiguous: 1524 return OR_Ambiguous; 1525 } 1526 1527 return OR_No_Viable_Function; 1528} 1529 1530bool 1531Sema::DiagnoseAmbiguousUserDefinedConversion(Expr *From, QualType ToType) { 1532 ImplicitConversionSequence ICS; 1533 OverloadCandidateSet CandidateSet; 1534 OverloadingResult OvResult = 1535 IsUserDefinedConversion(From, ToType, ICS.UserDefined, 1536 CandidateSet, true, false, false); 1537 if (OvResult != OR_Ambiguous) 1538 return false; 1539 Diag(From->getSourceRange().getBegin(), 1540 diag::err_typecheck_ambiguous_condition) 1541 << From->getType() << ToType << From->getSourceRange(); 1542 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1543 return true; 1544} 1545 1546/// CompareImplicitConversionSequences - Compare two implicit 1547/// conversion sequences to determine whether one is better than the 1548/// other or if they are indistinguishable (C++ 13.3.3.2). 1549ImplicitConversionSequence::CompareKind 1550Sema::CompareImplicitConversionSequences(const ImplicitConversionSequence& ICS1, 1551 const ImplicitConversionSequence& ICS2) 1552{ 1553 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit 1554 // conversion sequences (as defined in 13.3.3.1) 1555 // -- a standard conversion sequence (13.3.3.1.1) is a better 1556 // conversion sequence than a user-defined conversion sequence or 1557 // an ellipsis conversion sequence, and 1558 // -- a user-defined conversion sequence (13.3.3.1.2) is a better 1559 // conversion sequence than an ellipsis conversion sequence 1560 // (13.3.3.1.3). 1561 // 1562 if (ICS1.ConversionKind < ICS2.ConversionKind) 1563 return ImplicitConversionSequence::Better; 1564 else if (ICS2.ConversionKind < ICS1.ConversionKind) 1565 return ImplicitConversionSequence::Worse; 1566 1567 // Two implicit conversion sequences of the same form are 1568 // indistinguishable conversion sequences unless one of the 1569 // following rules apply: (C++ 13.3.3.2p3): 1570 if (ICS1.ConversionKind == ImplicitConversionSequence::StandardConversion) 1571 return CompareStandardConversionSequences(ICS1.Standard, ICS2.Standard); 1572 else if (ICS1.ConversionKind == 1573 ImplicitConversionSequence::UserDefinedConversion) { 1574 // User-defined conversion sequence U1 is a better conversion 1575 // sequence than another user-defined conversion sequence U2 if 1576 // they contain the same user-defined conversion function or 1577 // constructor and if the second standard conversion sequence of 1578 // U1 is better than the second standard conversion sequence of 1579 // U2 (C++ 13.3.3.2p3). 1580 if (ICS1.UserDefined.ConversionFunction == 1581 ICS2.UserDefined.ConversionFunction) 1582 return CompareStandardConversionSequences(ICS1.UserDefined.After, 1583 ICS2.UserDefined.After); 1584 } 1585 1586 return ImplicitConversionSequence::Indistinguishable; 1587} 1588 1589/// CompareStandardConversionSequences - Compare two standard 1590/// conversion sequences to determine whether one is better than the 1591/// other or if they are indistinguishable (C++ 13.3.3.2p3). 1592ImplicitConversionSequence::CompareKind 1593Sema::CompareStandardConversionSequences(const StandardConversionSequence& SCS1, 1594 const StandardConversionSequence& SCS2) 1595{ 1596 // Standard conversion sequence S1 is a better conversion sequence 1597 // than standard conversion sequence S2 if (C++ 13.3.3.2p3): 1598 1599 // -- S1 is a proper subsequence of S2 (comparing the conversion 1600 // sequences in the canonical form defined by 13.3.3.1.1, 1601 // excluding any Lvalue Transformation; the identity conversion 1602 // sequence is considered to be a subsequence of any 1603 // non-identity conversion sequence) or, if not that, 1604 if (SCS1.Second == SCS2.Second && SCS1.Third == SCS2.Third) 1605 // Neither is a proper subsequence of the other. Do nothing. 1606 ; 1607 else if ((SCS1.Second == ICK_Identity && SCS1.Third == SCS2.Third) || 1608 (SCS1.Third == ICK_Identity && SCS1.Second == SCS2.Second) || 1609 (SCS1.Second == ICK_Identity && 1610 SCS1.Third == ICK_Identity)) 1611 // SCS1 is a proper subsequence of SCS2. 1612 return ImplicitConversionSequence::Better; 1613 else if ((SCS2.Second == ICK_Identity && SCS2.Third == SCS1.Third) || 1614 (SCS2.Third == ICK_Identity && SCS2.Second == SCS1.Second) || 1615 (SCS2.Second == ICK_Identity && 1616 SCS2.Third == ICK_Identity)) 1617 // SCS2 is a proper subsequence of SCS1. 1618 return ImplicitConversionSequence::Worse; 1619 1620 // -- the rank of S1 is better than the rank of S2 (by the rules 1621 // defined below), or, if not that, 1622 ImplicitConversionRank Rank1 = SCS1.getRank(); 1623 ImplicitConversionRank Rank2 = SCS2.getRank(); 1624 if (Rank1 < Rank2) 1625 return ImplicitConversionSequence::Better; 1626 else if (Rank2 < Rank1) 1627 return ImplicitConversionSequence::Worse; 1628 1629 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank 1630 // are indistinguishable unless one of the following rules 1631 // applies: 1632 1633 // A conversion that is not a conversion of a pointer, or 1634 // pointer to member, to bool is better than another conversion 1635 // that is such a conversion. 1636 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool()) 1637 return SCS2.isPointerConversionToBool() 1638 ? ImplicitConversionSequence::Better 1639 : ImplicitConversionSequence::Worse; 1640 1641 // C++ [over.ics.rank]p4b2: 1642 // 1643 // If class B is derived directly or indirectly from class A, 1644 // conversion of B* to A* is better than conversion of B* to 1645 // void*, and conversion of A* to void* is better than conversion 1646 // of B* to void*. 1647 bool SCS1ConvertsToVoid 1648 = SCS1.isPointerConversionToVoidPointer(Context); 1649 bool SCS2ConvertsToVoid 1650 = SCS2.isPointerConversionToVoidPointer(Context); 1651 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) { 1652 // Exactly one of the conversion sequences is a conversion to 1653 // a void pointer; it's the worse conversion. 1654 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better 1655 : ImplicitConversionSequence::Worse; 1656 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) { 1657 // Neither conversion sequence converts to a void pointer; compare 1658 // their derived-to-base conversions. 1659 if (ImplicitConversionSequence::CompareKind DerivedCK 1660 = CompareDerivedToBaseConversions(SCS1, SCS2)) 1661 return DerivedCK; 1662 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid) { 1663 // Both conversion sequences are conversions to void 1664 // pointers. Compare the source types to determine if there's an 1665 // inheritance relationship in their sources. 1666 QualType FromType1 = QualType::getFromOpaquePtr(SCS1.FromTypePtr); 1667 QualType FromType2 = QualType::getFromOpaquePtr(SCS2.FromTypePtr); 1668 1669 // Adjust the types we're converting from via the array-to-pointer 1670 // conversion, if we need to. 1671 if (SCS1.First == ICK_Array_To_Pointer) 1672 FromType1 = Context.getArrayDecayedType(FromType1); 1673 if (SCS2.First == ICK_Array_To_Pointer) 1674 FromType2 = Context.getArrayDecayedType(FromType2); 1675 1676 QualType FromPointee1 1677 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 1678 QualType FromPointee2 1679 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 1680 1681 if (IsDerivedFrom(FromPointee2, FromPointee1)) 1682 return ImplicitConversionSequence::Better; 1683 else if (IsDerivedFrom(FromPointee1, FromPointee2)) 1684 return ImplicitConversionSequence::Worse; 1685 1686 // Objective-C++: If one interface is more specific than the 1687 // other, it is the better one. 1688 const ObjCInterfaceType* FromIface1 = FromPointee1->getAs<ObjCInterfaceType>(); 1689 const ObjCInterfaceType* FromIface2 = FromPointee2->getAs<ObjCInterfaceType>(); 1690 if (FromIface1 && FromIface1) { 1691 if (Context.canAssignObjCInterfaces(FromIface2, FromIface1)) 1692 return ImplicitConversionSequence::Better; 1693 else if (Context.canAssignObjCInterfaces(FromIface1, FromIface2)) 1694 return ImplicitConversionSequence::Worse; 1695 } 1696 } 1697 1698 // Compare based on qualification conversions (C++ 13.3.3.2p3, 1699 // bullet 3). 1700 if (ImplicitConversionSequence::CompareKind QualCK 1701 = CompareQualificationConversions(SCS1, SCS2)) 1702 return QualCK; 1703 1704 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) { 1705 // C++0x [over.ics.rank]p3b4: 1706 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an 1707 // implicit object parameter of a non-static member function declared 1708 // without a ref-qualifier, and S1 binds an rvalue reference to an 1709 // rvalue and S2 binds an lvalue reference. 1710 // FIXME: We don't know if we're dealing with the implicit object parameter, 1711 // or if the member function in this case has a ref qualifier. 1712 // (Of course, we don't have ref qualifiers yet.) 1713 if (SCS1.RRefBinding != SCS2.RRefBinding) 1714 return SCS1.RRefBinding ? ImplicitConversionSequence::Better 1715 : ImplicitConversionSequence::Worse; 1716 1717 // C++ [over.ics.rank]p3b4: 1718 // -- S1 and S2 are reference bindings (8.5.3), and the types to 1719 // which the references refer are the same type except for 1720 // top-level cv-qualifiers, and the type to which the reference 1721 // initialized by S2 refers is more cv-qualified than the type 1722 // to which the reference initialized by S1 refers. 1723 QualType T1 = QualType::getFromOpaquePtr(SCS1.ToTypePtr); 1724 QualType T2 = QualType::getFromOpaquePtr(SCS2.ToTypePtr); 1725 T1 = Context.getCanonicalType(T1); 1726 T2 = Context.getCanonicalType(T2); 1727 if (T1.getUnqualifiedType() == T2.getUnqualifiedType()) { 1728 if (T2.isMoreQualifiedThan(T1)) 1729 return ImplicitConversionSequence::Better; 1730 else if (T1.isMoreQualifiedThan(T2)) 1731 return ImplicitConversionSequence::Worse; 1732 } 1733 } 1734 1735 return ImplicitConversionSequence::Indistinguishable; 1736} 1737 1738/// CompareQualificationConversions - Compares two standard conversion 1739/// sequences to determine whether they can be ranked based on their 1740/// qualification conversions (C++ 13.3.3.2p3 bullet 3). 1741ImplicitConversionSequence::CompareKind 1742Sema::CompareQualificationConversions(const StandardConversionSequence& SCS1, 1743 const StandardConversionSequence& SCS2) { 1744 // C++ 13.3.3.2p3: 1745 // -- S1 and S2 differ only in their qualification conversion and 1746 // yield similar types T1 and T2 (C++ 4.4), respectively, and the 1747 // cv-qualification signature of type T1 is a proper subset of 1748 // the cv-qualification signature of type T2, and S1 is not the 1749 // deprecated string literal array-to-pointer conversion (4.2). 1750 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second || 1751 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification) 1752 return ImplicitConversionSequence::Indistinguishable; 1753 1754 // FIXME: the example in the standard doesn't use a qualification 1755 // conversion (!) 1756 QualType T1 = QualType::getFromOpaquePtr(SCS1.ToTypePtr); 1757 QualType T2 = QualType::getFromOpaquePtr(SCS2.ToTypePtr); 1758 T1 = Context.getCanonicalType(T1); 1759 T2 = Context.getCanonicalType(T2); 1760 1761 // If the types are the same, we won't learn anything by unwrapped 1762 // them. 1763 if (T1.getUnqualifiedType() == T2.getUnqualifiedType()) 1764 return ImplicitConversionSequence::Indistinguishable; 1765 1766 ImplicitConversionSequence::CompareKind Result 1767 = ImplicitConversionSequence::Indistinguishable; 1768 while (UnwrapSimilarPointerTypes(T1, T2)) { 1769 // Within each iteration of the loop, we check the qualifiers to 1770 // determine if this still looks like a qualification 1771 // conversion. Then, if all is well, we unwrap one more level of 1772 // pointers or pointers-to-members and do it all again 1773 // until there are no more pointers or pointers-to-members left 1774 // to unwrap. This essentially mimics what 1775 // IsQualificationConversion does, but here we're checking for a 1776 // strict subset of qualifiers. 1777 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 1778 // The qualifiers are the same, so this doesn't tell us anything 1779 // about how the sequences rank. 1780 ; 1781 else if (T2.isMoreQualifiedThan(T1)) { 1782 // T1 has fewer qualifiers, so it could be the better sequence. 1783 if (Result == ImplicitConversionSequence::Worse) 1784 // Neither has qualifiers that are a subset of the other's 1785 // qualifiers. 1786 return ImplicitConversionSequence::Indistinguishable; 1787 1788 Result = ImplicitConversionSequence::Better; 1789 } else if (T1.isMoreQualifiedThan(T2)) { 1790 // T2 has fewer qualifiers, so it could be the better sequence. 1791 if (Result == ImplicitConversionSequence::Better) 1792 // Neither has qualifiers that are a subset of the other's 1793 // qualifiers. 1794 return ImplicitConversionSequence::Indistinguishable; 1795 1796 Result = ImplicitConversionSequence::Worse; 1797 } else { 1798 // Qualifiers are disjoint. 1799 return ImplicitConversionSequence::Indistinguishable; 1800 } 1801 1802 // If the types after this point are equivalent, we're done. 1803 if (T1.getUnqualifiedType() == T2.getUnqualifiedType()) 1804 break; 1805 } 1806 1807 // Check that the winning standard conversion sequence isn't using 1808 // the deprecated string literal array to pointer conversion. 1809 switch (Result) { 1810 case ImplicitConversionSequence::Better: 1811 if (SCS1.Deprecated) 1812 Result = ImplicitConversionSequence::Indistinguishable; 1813 break; 1814 1815 case ImplicitConversionSequence::Indistinguishable: 1816 break; 1817 1818 case ImplicitConversionSequence::Worse: 1819 if (SCS2.Deprecated) 1820 Result = ImplicitConversionSequence::Indistinguishable; 1821 break; 1822 } 1823 1824 return Result; 1825} 1826 1827/// CompareDerivedToBaseConversions - Compares two standard conversion 1828/// sequences to determine whether they can be ranked based on their 1829/// various kinds of derived-to-base conversions (C++ 1830/// [over.ics.rank]p4b3). As part of these checks, we also look at 1831/// conversions between Objective-C interface types. 1832ImplicitConversionSequence::CompareKind 1833Sema::CompareDerivedToBaseConversions(const StandardConversionSequence& SCS1, 1834 const StandardConversionSequence& SCS2) { 1835 QualType FromType1 = QualType::getFromOpaquePtr(SCS1.FromTypePtr); 1836 QualType ToType1 = QualType::getFromOpaquePtr(SCS1.ToTypePtr); 1837 QualType FromType2 = QualType::getFromOpaquePtr(SCS2.FromTypePtr); 1838 QualType ToType2 = QualType::getFromOpaquePtr(SCS2.ToTypePtr); 1839 1840 // Adjust the types we're converting from via the array-to-pointer 1841 // conversion, if we need to. 1842 if (SCS1.First == ICK_Array_To_Pointer) 1843 FromType1 = Context.getArrayDecayedType(FromType1); 1844 if (SCS2.First == ICK_Array_To_Pointer) 1845 FromType2 = Context.getArrayDecayedType(FromType2); 1846 1847 // Canonicalize all of the types. 1848 FromType1 = Context.getCanonicalType(FromType1); 1849 ToType1 = Context.getCanonicalType(ToType1); 1850 FromType2 = Context.getCanonicalType(FromType2); 1851 ToType2 = Context.getCanonicalType(ToType2); 1852 1853 // C++ [over.ics.rank]p4b3: 1854 // 1855 // If class B is derived directly or indirectly from class A and 1856 // class C is derived directly or indirectly from B, 1857 // 1858 // For Objective-C, we let A, B, and C also be Objective-C 1859 // interfaces. 1860 1861 // Compare based on pointer conversions. 1862 if (SCS1.Second == ICK_Pointer_Conversion && 1863 SCS2.Second == ICK_Pointer_Conversion && 1864 /*FIXME: Remove if Objective-C id conversions get their own rank*/ 1865 FromType1->isPointerType() && FromType2->isPointerType() && 1866 ToType1->isPointerType() && ToType2->isPointerType()) { 1867 QualType FromPointee1 1868 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 1869 QualType ToPointee1 1870 = ToType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 1871 QualType FromPointee2 1872 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 1873 QualType ToPointee2 1874 = ToType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 1875 1876 const ObjCInterfaceType* FromIface1 = FromPointee1->getAs<ObjCInterfaceType>(); 1877 const ObjCInterfaceType* FromIface2 = FromPointee2->getAs<ObjCInterfaceType>(); 1878 const ObjCInterfaceType* ToIface1 = ToPointee1->getAs<ObjCInterfaceType>(); 1879 const ObjCInterfaceType* ToIface2 = ToPointee2->getAs<ObjCInterfaceType>(); 1880 1881 // -- conversion of C* to B* is better than conversion of C* to A*, 1882 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 1883 if (IsDerivedFrom(ToPointee1, ToPointee2)) 1884 return ImplicitConversionSequence::Better; 1885 else if (IsDerivedFrom(ToPointee2, ToPointee1)) 1886 return ImplicitConversionSequence::Worse; 1887 1888 if (ToIface1 && ToIface2) { 1889 if (Context.canAssignObjCInterfaces(ToIface2, ToIface1)) 1890 return ImplicitConversionSequence::Better; 1891 else if (Context.canAssignObjCInterfaces(ToIface1, ToIface2)) 1892 return ImplicitConversionSequence::Worse; 1893 } 1894 } 1895 1896 // -- conversion of B* to A* is better than conversion of C* to A*, 1897 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) { 1898 if (IsDerivedFrom(FromPointee2, FromPointee1)) 1899 return ImplicitConversionSequence::Better; 1900 else if (IsDerivedFrom(FromPointee1, FromPointee2)) 1901 return ImplicitConversionSequence::Worse; 1902 1903 if (FromIface1 && FromIface2) { 1904 if (Context.canAssignObjCInterfaces(FromIface1, FromIface2)) 1905 return ImplicitConversionSequence::Better; 1906 else if (Context.canAssignObjCInterfaces(FromIface2, FromIface1)) 1907 return ImplicitConversionSequence::Worse; 1908 } 1909 } 1910 } 1911 1912 // Compare based on reference bindings. 1913 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding && 1914 SCS1.Second == ICK_Derived_To_Base) { 1915 // -- binding of an expression of type C to a reference of type 1916 // B& is better than binding an expression of type C to a 1917 // reference of type A&, 1918 if (FromType1.getUnqualifiedType() == FromType2.getUnqualifiedType() && 1919 ToType1.getUnqualifiedType() != ToType2.getUnqualifiedType()) { 1920 if (IsDerivedFrom(ToType1, ToType2)) 1921 return ImplicitConversionSequence::Better; 1922 else if (IsDerivedFrom(ToType2, ToType1)) 1923 return ImplicitConversionSequence::Worse; 1924 } 1925 1926 // -- binding of an expression of type B to a reference of type 1927 // A& is better than binding an expression of type C to a 1928 // reference of type A&, 1929 if (FromType1.getUnqualifiedType() != FromType2.getUnqualifiedType() && 1930 ToType1.getUnqualifiedType() == ToType2.getUnqualifiedType()) { 1931 if (IsDerivedFrom(FromType2, FromType1)) 1932 return ImplicitConversionSequence::Better; 1933 else if (IsDerivedFrom(FromType1, FromType2)) 1934 return ImplicitConversionSequence::Worse; 1935 } 1936 } 1937 1938 // Ranking of member-pointer types. 1939 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member && 1940 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() && 1941 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) { 1942 const MemberPointerType * FromMemPointer1 = 1943 FromType1->getAs<MemberPointerType>(); 1944 const MemberPointerType * ToMemPointer1 = 1945 ToType1->getAs<MemberPointerType>(); 1946 const MemberPointerType * FromMemPointer2 = 1947 FromType2->getAs<MemberPointerType>(); 1948 const MemberPointerType * ToMemPointer2 = 1949 ToType2->getAs<MemberPointerType>(); 1950 const Type *FromPointeeType1 = FromMemPointer1->getClass(); 1951 const Type *ToPointeeType1 = ToMemPointer1->getClass(); 1952 const Type *FromPointeeType2 = FromMemPointer2->getClass(); 1953 const Type *ToPointeeType2 = ToMemPointer2->getClass(); 1954 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType(); 1955 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType(); 1956 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType(); 1957 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType(); 1958 // conversion of A::* to B::* is better than conversion of A::* to C::*, 1959 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 1960 if (IsDerivedFrom(ToPointee1, ToPointee2)) 1961 return ImplicitConversionSequence::Worse; 1962 else if (IsDerivedFrom(ToPointee2, ToPointee1)) 1963 return ImplicitConversionSequence::Better; 1964 } 1965 // conversion of B::* to C::* is better than conversion of A::* to C::* 1966 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) { 1967 if (IsDerivedFrom(FromPointee1, FromPointee2)) 1968 return ImplicitConversionSequence::Better; 1969 else if (IsDerivedFrom(FromPointee2, FromPointee1)) 1970 return ImplicitConversionSequence::Worse; 1971 } 1972 } 1973 1974 if (SCS1.CopyConstructor && SCS2.CopyConstructor && 1975 SCS1.Second == ICK_Derived_To_Base) { 1976 // -- conversion of C to B is better than conversion of C to A, 1977 if (FromType1.getUnqualifiedType() == FromType2.getUnqualifiedType() && 1978 ToType1.getUnqualifiedType() != ToType2.getUnqualifiedType()) { 1979 if (IsDerivedFrom(ToType1, ToType2)) 1980 return ImplicitConversionSequence::Better; 1981 else if (IsDerivedFrom(ToType2, ToType1)) 1982 return ImplicitConversionSequence::Worse; 1983 } 1984 1985 // -- conversion of B to A is better than conversion of C to A. 1986 if (FromType1.getUnqualifiedType() != FromType2.getUnqualifiedType() && 1987 ToType1.getUnqualifiedType() == ToType2.getUnqualifiedType()) { 1988 if (IsDerivedFrom(FromType2, FromType1)) 1989 return ImplicitConversionSequence::Better; 1990 else if (IsDerivedFrom(FromType1, FromType2)) 1991 return ImplicitConversionSequence::Worse; 1992 } 1993 } 1994 1995 return ImplicitConversionSequence::Indistinguishable; 1996} 1997 1998/// TryCopyInitialization - Try to copy-initialize a value of type 1999/// ToType from the expression From. Return the implicit conversion 2000/// sequence required to pass this argument, which may be a bad 2001/// conversion sequence (meaning that the argument cannot be passed to 2002/// a parameter of this type). If @p SuppressUserConversions, then we 2003/// do not permit any user-defined conversion sequences. If @p ForceRValue, 2004/// then we treat @p From as an rvalue, even if it is an lvalue. 2005ImplicitConversionSequence 2006Sema::TryCopyInitialization(Expr *From, QualType ToType, 2007 bool SuppressUserConversions, bool ForceRValue, 2008 bool InOverloadResolution) { 2009 if (ToType->isReferenceType()) { 2010 ImplicitConversionSequence ICS; 2011 CheckReferenceInit(From, ToType, 2012 /*FIXME:*/From->getLocStart(), 2013 SuppressUserConversions, 2014 /*AllowExplicit=*/false, 2015 ForceRValue, 2016 &ICS); 2017 return ICS; 2018 } else { 2019 return TryImplicitConversion(From, ToType, 2020 SuppressUserConversions, 2021 /*AllowExplicit=*/false, 2022 ForceRValue, 2023 InOverloadResolution); 2024 } 2025} 2026 2027/// PerformCopyInitialization - Copy-initialize an object of type @p ToType with 2028/// the expression @p From. Returns true (and emits a diagnostic) if there was 2029/// an error, returns false if the initialization succeeded. Elidable should 2030/// be true when the copy may be elided (C++ 12.8p15). Overload resolution works 2031/// differently in C++0x for this case. 2032bool Sema::PerformCopyInitialization(Expr *&From, QualType ToType, 2033 const char* Flavor, bool Elidable) { 2034 if (!getLangOptions().CPlusPlus) { 2035 // In C, argument passing is the same as performing an assignment. 2036 QualType FromType = From->getType(); 2037 2038 AssignConvertType ConvTy = 2039 CheckSingleAssignmentConstraints(ToType, From); 2040 if (ConvTy != Compatible && 2041 CheckTransparentUnionArgumentConstraints(ToType, From) == Compatible) 2042 ConvTy = Compatible; 2043 2044 return DiagnoseAssignmentResult(ConvTy, From->getLocStart(), ToType, 2045 FromType, From, Flavor); 2046 } 2047 2048 if (ToType->isReferenceType()) 2049 return CheckReferenceInit(From, ToType, 2050 /*FIXME:*/From->getLocStart(), 2051 /*SuppressUserConversions=*/false, 2052 /*AllowExplicit=*/false, 2053 /*ForceRValue=*/false); 2054 2055 if (!PerformImplicitConversion(From, ToType, Flavor, 2056 /*AllowExplicit=*/false, Elidable)) 2057 return false; 2058 if (!DiagnoseAmbiguousUserDefinedConversion(From, ToType)) 2059 return Diag(From->getSourceRange().getBegin(), 2060 diag::err_typecheck_convert_incompatible) 2061 << ToType << From->getType() << Flavor << From->getSourceRange(); 2062 return true; 2063} 2064 2065/// TryObjectArgumentInitialization - Try to initialize the object 2066/// parameter of the given member function (@c Method) from the 2067/// expression @p From. 2068ImplicitConversionSequence 2069Sema::TryObjectArgumentInitialization(Expr *From, CXXMethodDecl *Method) { 2070 QualType ClassType = Context.getTypeDeclType(Method->getParent()); 2071 QualType ImplicitParamType 2072 = Context.getCVRQualifiedType(ClassType, Method->getTypeQualifiers()); 2073 2074 // Set up the conversion sequence as a "bad" conversion, to allow us 2075 // to exit early. 2076 ImplicitConversionSequence ICS; 2077 ICS.Standard.setAsIdentityConversion(); 2078 ICS.ConversionKind = ImplicitConversionSequence::BadConversion; 2079 2080 // We need to have an object of class type. 2081 QualType FromType = From->getType(); 2082 if (const PointerType *PT = FromType->getAs<PointerType>()) 2083 FromType = PT->getPointeeType(); 2084 2085 assert(FromType->isRecordType()); 2086 2087 // The implicit object parmeter is has the type "reference to cv X", 2088 // where X is the class of which the function is a member 2089 // (C++ [over.match.funcs]p4). However, when finding an implicit 2090 // conversion sequence for the argument, we are not allowed to 2091 // create temporaries or perform user-defined conversions 2092 // (C++ [over.match.funcs]p5). We perform a simplified version of 2093 // reference binding here, that allows class rvalues to bind to 2094 // non-constant references. 2095 2096 // First check the qualifiers. We don't care about lvalue-vs-rvalue 2097 // with the implicit object parameter (C++ [over.match.funcs]p5). 2098 QualType FromTypeCanon = Context.getCanonicalType(FromType); 2099 if (ImplicitParamType.getCVRQualifiers() != FromType.getCVRQualifiers() && 2100 !ImplicitParamType.isAtLeastAsQualifiedAs(FromType)) 2101 return ICS; 2102 2103 // Check that we have either the same type or a derived type. It 2104 // affects the conversion rank. 2105 QualType ClassTypeCanon = Context.getCanonicalType(ClassType); 2106 if (ClassTypeCanon == FromTypeCanon.getUnqualifiedType()) 2107 ICS.Standard.Second = ICK_Identity; 2108 else if (IsDerivedFrom(FromType, ClassType)) 2109 ICS.Standard.Second = ICK_Derived_To_Base; 2110 else 2111 return ICS; 2112 2113 // Success. Mark this as a reference binding. 2114 ICS.ConversionKind = ImplicitConversionSequence::StandardConversion; 2115 ICS.Standard.FromTypePtr = FromType.getAsOpaquePtr(); 2116 ICS.Standard.ToTypePtr = ImplicitParamType.getAsOpaquePtr(); 2117 ICS.Standard.ReferenceBinding = true; 2118 ICS.Standard.DirectBinding = true; 2119 ICS.Standard.RRefBinding = false; 2120 return ICS; 2121} 2122 2123/// PerformObjectArgumentInitialization - Perform initialization of 2124/// the implicit object parameter for the given Method with the given 2125/// expression. 2126bool 2127Sema::PerformObjectArgumentInitialization(Expr *&From, CXXMethodDecl *Method) { 2128 QualType FromRecordType, DestType; 2129 QualType ImplicitParamRecordType = 2130 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType(); 2131 2132 if (const PointerType *PT = From->getType()->getAs<PointerType>()) { 2133 FromRecordType = PT->getPointeeType(); 2134 DestType = Method->getThisType(Context); 2135 } else { 2136 FromRecordType = From->getType(); 2137 DestType = ImplicitParamRecordType; 2138 } 2139 2140 ImplicitConversionSequence ICS 2141 = TryObjectArgumentInitialization(From, Method); 2142 if (ICS.ConversionKind == ImplicitConversionSequence::BadConversion) 2143 return Diag(From->getSourceRange().getBegin(), 2144 diag::err_implicit_object_parameter_init) 2145 << ImplicitParamRecordType << FromRecordType << From->getSourceRange(); 2146 2147 if (ICS.Standard.Second == ICK_Derived_To_Base && 2148 CheckDerivedToBaseConversion(FromRecordType, 2149 ImplicitParamRecordType, 2150 From->getSourceRange().getBegin(), 2151 From->getSourceRange())) 2152 return true; 2153 2154 ImpCastExprToType(From, DestType, CastExpr::CK_DerivedToBase, 2155 /*isLvalue=*/true); 2156 return false; 2157} 2158 2159/// TryContextuallyConvertToBool - Attempt to contextually convert the 2160/// expression From to bool (C++0x [conv]p3). 2161ImplicitConversionSequence Sema::TryContextuallyConvertToBool(Expr *From) { 2162 return TryImplicitConversion(From, Context.BoolTy, 2163 // FIXME: Are these flags correct? 2164 /*SuppressUserConversions=*/false, 2165 /*AllowExplicit=*/true, 2166 /*ForceRValue=*/false, 2167 /*InOverloadResolution=*/false); 2168} 2169 2170/// PerformContextuallyConvertToBool - Perform a contextual conversion 2171/// of the expression From to bool (C++0x [conv]p3). 2172bool Sema::PerformContextuallyConvertToBool(Expr *&From) { 2173 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(From); 2174 if (!PerformImplicitConversion(From, Context.BoolTy, ICS, "converting")) 2175 return false; 2176 2177 if (!DiagnoseAmbiguousUserDefinedConversion(From, Context.BoolTy)) 2178 return Diag(From->getSourceRange().getBegin(), 2179 diag::err_typecheck_bool_condition) 2180 << From->getType() << From->getSourceRange(); 2181 return true; 2182} 2183 2184/// AddOverloadCandidate - Adds the given function to the set of 2185/// candidate functions, using the given function call arguments. If 2186/// @p SuppressUserConversions, then don't allow user-defined 2187/// conversions via constructors or conversion operators. 2188/// If @p ForceRValue, treat all arguments as rvalues. This is a slightly 2189/// hacky way to implement the overloading rules for elidable copy 2190/// initialization in C++0x (C++0x 12.8p15). 2191/// 2192/// \para PartialOverloading true if we are performing "partial" overloading 2193/// based on an incomplete set of function arguments. This feature is used by 2194/// code completion. 2195void 2196Sema::AddOverloadCandidate(FunctionDecl *Function, 2197 Expr **Args, unsigned NumArgs, 2198 OverloadCandidateSet& CandidateSet, 2199 bool SuppressUserConversions, 2200 bool ForceRValue, 2201 bool PartialOverloading) { 2202 const FunctionProtoType* Proto 2203 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>()); 2204 assert(Proto && "Functions without a prototype cannot be overloaded"); 2205 assert(!isa<CXXConversionDecl>(Function) && 2206 "Use AddConversionCandidate for conversion functions"); 2207 assert(!Function->getDescribedFunctionTemplate() && 2208 "Use AddTemplateOverloadCandidate for function templates"); 2209 2210 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 2211 if (!isa<CXXConstructorDecl>(Method)) { 2212 // If we get here, it's because we're calling a member function 2213 // that is named without a member access expression (e.g., 2214 // "this->f") that was either written explicitly or created 2215 // implicitly. This can happen with a qualified call to a member 2216 // function, e.g., X::f(). We use a NULL object as the implied 2217 // object argument (C++ [over.call.func]p3). 2218 AddMethodCandidate(Method, 0, Args, NumArgs, CandidateSet, 2219 SuppressUserConversions, ForceRValue); 2220 return; 2221 } 2222 // We treat a constructor like a non-member function, since its object 2223 // argument doesn't participate in overload resolution. 2224 } 2225 2226 if (!CandidateSet.isNewCandidate(Function)) 2227 return; 2228 2229 // Add this candidate 2230 CandidateSet.push_back(OverloadCandidate()); 2231 OverloadCandidate& Candidate = CandidateSet.back(); 2232 Candidate.Function = Function; 2233 Candidate.Viable = true; 2234 Candidate.IsSurrogate = false; 2235 Candidate.IgnoreObjectArgument = false; 2236 2237 unsigned NumArgsInProto = Proto->getNumArgs(); 2238 2239 // (C++ 13.3.2p2): A candidate function having fewer than m 2240 // parameters is viable only if it has an ellipsis in its parameter 2241 // list (8.3.5). 2242 if ((NumArgs + (PartialOverloading && NumArgs)) > NumArgsInProto && 2243 !Proto->isVariadic()) { 2244 Candidate.Viable = false; 2245 return; 2246 } 2247 2248 // (C++ 13.3.2p2): A candidate function having more than m parameters 2249 // is viable only if the (m+1)st parameter has a default argument 2250 // (8.3.6). For the purposes of overload resolution, the 2251 // parameter list is truncated on the right, so that there are 2252 // exactly m parameters. 2253 unsigned MinRequiredArgs = Function->getMinRequiredArguments(); 2254 if (NumArgs < MinRequiredArgs && !PartialOverloading) { 2255 // Not enough arguments. 2256 Candidate.Viable = false; 2257 return; 2258 } 2259 2260 // Determine the implicit conversion sequences for each of the 2261 // arguments. 2262 Candidate.Conversions.resize(NumArgs); 2263 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 2264 if (ArgIdx < NumArgsInProto) { 2265 // (C++ 13.3.2p3): for F to be a viable function, there shall 2266 // exist for each argument an implicit conversion sequence 2267 // (13.3.3.1) that converts that argument to the corresponding 2268 // parameter of F. 2269 QualType ParamType = Proto->getArgType(ArgIdx); 2270 Candidate.Conversions[ArgIdx] 2271 = TryCopyInitialization(Args[ArgIdx], ParamType, 2272 SuppressUserConversions, ForceRValue, 2273 /*InOverloadResolution=*/true); 2274 if (Candidate.Conversions[ArgIdx].ConversionKind 2275 == ImplicitConversionSequence::BadConversion) { 2276 // 13.3.3.1-p10 If several different sequences of conversions exist that 2277 // each convert the argument to the parameter type, the implicit conversion 2278 // sequence associated with the parameter is defined to be the unique conversion 2279 // sequence designated the ambiguous conversion sequence. For the purpose of 2280 // ranking implicit conversion sequences as described in 13.3.3.2, the ambiguous 2281 // conversion sequence is treated as a user-defined sequence that is 2282 // indistinguishable from any other user-defined conversion sequence 2283 if (!Candidate.Conversions[ArgIdx].ConversionFunctionSet.empty()) { 2284 Candidate.Conversions[ArgIdx].ConversionKind = 2285 ImplicitConversionSequence::UserDefinedConversion; 2286 // Set the conversion function to one of them. As due to ambiguity, 2287 // they carry the same weight and is needed for overload resolution 2288 // later. 2289 Candidate.Conversions[ArgIdx].UserDefined.ConversionFunction = 2290 Candidate.Conversions[ArgIdx].ConversionFunctionSet[0]; 2291 } 2292 else { 2293 Candidate.Viable = false; 2294 break; 2295 } 2296 } 2297 } else { 2298 // (C++ 13.3.2p2): For the purposes of overload resolution, any 2299 // argument for which there is no corresponding parameter is 2300 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 2301 Candidate.Conversions[ArgIdx].ConversionKind 2302 = ImplicitConversionSequence::EllipsisConversion; 2303 } 2304 } 2305} 2306 2307/// \brief Add all of the function declarations in the given function set to 2308/// the overload canddiate set. 2309void Sema::AddFunctionCandidates(const FunctionSet &Functions, 2310 Expr **Args, unsigned NumArgs, 2311 OverloadCandidateSet& CandidateSet, 2312 bool SuppressUserConversions) { 2313 for (FunctionSet::const_iterator F = Functions.begin(), 2314 FEnd = Functions.end(); 2315 F != FEnd; ++F) { 2316 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*F)) { 2317 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 2318 AddMethodCandidate(cast<CXXMethodDecl>(FD), 2319 Args[0], Args + 1, NumArgs - 1, 2320 CandidateSet, SuppressUserConversions); 2321 else 2322 AddOverloadCandidate(FD, Args, NumArgs, CandidateSet, 2323 SuppressUserConversions); 2324 } else { 2325 FunctionTemplateDecl *FunTmpl = cast<FunctionTemplateDecl>(*F); 2326 if (isa<CXXMethodDecl>(FunTmpl->getTemplatedDecl()) && 2327 !cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())->isStatic()) 2328 AddMethodTemplateCandidate(FunTmpl, 2329 /*FIXME: explicit args */false, 0, 0, 2330 Args[0], Args + 1, NumArgs - 1, 2331 CandidateSet, 2332 SuppressUserConversions); 2333 else 2334 AddTemplateOverloadCandidate(FunTmpl, 2335 /*FIXME: explicit args */false, 0, 0, 2336 Args, NumArgs, CandidateSet, 2337 SuppressUserConversions); 2338 } 2339 } 2340} 2341 2342/// AddMethodCandidate - Adds the given C++ member function to the set 2343/// of candidate functions, using the given function call arguments 2344/// and the object argument (@c Object). For example, in a call 2345/// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain 2346/// both @c a1 and @c a2. If @p SuppressUserConversions, then don't 2347/// allow user-defined conversions via constructors or conversion 2348/// operators. If @p ForceRValue, treat all arguments as rvalues. This is 2349/// a slightly hacky way to implement the overloading rules for elidable copy 2350/// initialization in C++0x (C++0x 12.8p15). 2351void 2352Sema::AddMethodCandidate(CXXMethodDecl *Method, Expr *Object, 2353 Expr **Args, unsigned NumArgs, 2354 OverloadCandidateSet& CandidateSet, 2355 bool SuppressUserConversions, bool ForceRValue) { 2356 const FunctionProtoType* Proto 2357 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>()); 2358 assert(Proto && "Methods without a prototype cannot be overloaded"); 2359 assert(!isa<CXXConversionDecl>(Method) && 2360 "Use AddConversionCandidate for conversion functions"); 2361 assert(!isa<CXXConstructorDecl>(Method) && 2362 "Use AddOverloadCandidate for constructors"); 2363 2364 if (!CandidateSet.isNewCandidate(Method)) 2365 return; 2366 2367 // Add this candidate 2368 CandidateSet.push_back(OverloadCandidate()); 2369 OverloadCandidate& Candidate = CandidateSet.back(); 2370 Candidate.Function = Method; 2371 Candidate.IsSurrogate = false; 2372 Candidate.IgnoreObjectArgument = false; 2373 2374 unsigned NumArgsInProto = Proto->getNumArgs(); 2375 2376 // (C++ 13.3.2p2): A candidate function having fewer than m 2377 // parameters is viable only if it has an ellipsis in its parameter 2378 // list (8.3.5). 2379 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 2380 Candidate.Viable = false; 2381 return; 2382 } 2383 2384 // (C++ 13.3.2p2): A candidate function having more than m parameters 2385 // is viable only if the (m+1)st parameter has a default argument 2386 // (8.3.6). For the purposes of overload resolution, the 2387 // parameter list is truncated on the right, so that there are 2388 // exactly m parameters. 2389 unsigned MinRequiredArgs = Method->getMinRequiredArguments(); 2390 if (NumArgs < MinRequiredArgs) { 2391 // Not enough arguments. 2392 Candidate.Viable = false; 2393 return; 2394 } 2395 2396 Candidate.Viable = true; 2397 Candidate.Conversions.resize(NumArgs + 1); 2398 2399 if (Method->isStatic() || !Object) 2400 // The implicit object argument is ignored. 2401 Candidate.IgnoreObjectArgument = true; 2402 else { 2403 // Determine the implicit conversion sequence for the object 2404 // parameter. 2405 Candidate.Conversions[0] = TryObjectArgumentInitialization(Object, Method); 2406 if (Candidate.Conversions[0].ConversionKind 2407 == ImplicitConversionSequence::BadConversion) { 2408 Candidate.Viable = false; 2409 return; 2410 } 2411 } 2412 2413 // Determine the implicit conversion sequences for each of the 2414 // arguments. 2415 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 2416 if (ArgIdx < NumArgsInProto) { 2417 // (C++ 13.3.2p3): for F to be a viable function, there shall 2418 // exist for each argument an implicit conversion sequence 2419 // (13.3.3.1) that converts that argument to the corresponding 2420 // parameter of F. 2421 QualType ParamType = Proto->getArgType(ArgIdx); 2422 Candidate.Conversions[ArgIdx + 1] 2423 = TryCopyInitialization(Args[ArgIdx], ParamType, 2424 SuppressUserConversions, ForceRValue, 2425 /*InOverloadResolution=*/true); 2426 if (Candidate.Conversions[ArgIdx + 1].ConversionKind 2427 == ImplicitConversionSequence::BadConversion) { 2428 Candidate.Viable = false; 2429 break; 2430 } 2431 } else { 2432 // (C++ 13.3.2p2): For the purposes of overload resolution, any 2433 // argument for which there is no corresponding parameter is 2434 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 2435 Candidate.Conversions[ArgIdx + 1].ConversionKind 2436 = ImplicitConversionSequence::EllipsisConversion; 2437 } 2438 } 2439} 2440 2441/// \brief Add a C++ member function template as a candidate to the candidate 2442/// set, using template argument deduction to produce an appropriate member 2443/// function template specialization. 2444void 2445Sema::AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl, 2446 bool HasExplicitTemplateArgs, 2447 const TemplateArgument *ExplicitTemplateArgs, 2448 unsigned NumExplicitTemplateArgs, 2449 Expr *Object, Expr **Args, unsigned NumArgs, 2450 OverloadCandidateSet& CandidateSet, 2451 bool SuppressUserConversions, 2452 bool ForceRValue) { 2453 if (!CandidateSet.isNewCandidate(MethodTmpl)) 2454 return; 2455 2456 // C++ [over.match.funcs]p7: 2457 // In each case where a candidate is a function template, candidate 2458 // function template specializations are generated using template argument 2459 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 2460 // candidate functions in the usual way.113) A given name can refer to one 2461 // or more function templates and also to a set of overloaded non-template 2462 // functions. In such a case, the candidate functions generated from each 2463 // function template are combined with the set of non-template candidate 2464 // functions. 2465 TemplateDeductionInfo Info(Context); 2466 FunctionDecl *Specialization = 0; 2467 if (TemplateDeductionResult Result 2468 = DeduceTemplateArguments(MethodTmpl, HasExplicitTemplateArgs, 2469 ExplicitTemplateArgs, NumExplicitTemplateArgs, 2470 Args, NumArgs, Specialization, Info)) { 2471 // FIXME: Record what happened with template argument deduction, so 2472 // that we can give the user a beautiful diagnostic. 2473 (void)Result; 2474 return; 2475 } 2476 2477 // Add the function template specialization produced by template argument 2478 // deduction as a candidate. 2479 assert(Specialization && "Missing member function template specialization?"); 2480 assert(isa<CXXMethodDecl>(Specialization) && 2481 "Specialization is not a member function?"); 2482 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), Object, Args, NumArgs, 2483 CandidateSet, SuppressUserConversions, ForceRValue); 2484} 2485 2486/// \brief Add a C++ function template specialization as a candidate 2487/// in the candidate set, using template argument deduction to produce 2488/// an appropriate function template specialization. 2489void 2490Sema::AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate, 2491 bool HasExplicitTemplateArgs, 2492 const TemplateArgument *ExplicitTemplateArgs, 2493 unsigned NumExplicitTemplateArgs, 2494 Expr **Args, unsigned NumArgs, 2495 OverloadCandidateSet& CandidateSet, 2496 bool SuppressUserConversions, 2497 bool ForceRValue) { 2498 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 2499 return; 2500 2501 // C++ [over.match.funcs]p7: 2502 // In each case where a candidate is a function template, candidate 2503 // function template specializations are generated using template argument 2504 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 2505 // candidate functions in the usual way.113) A given name can refer to one 2506 // or more function templates and also to a set of overloaded non-template 2507 // functions. In such a case, the candidate functions generated from each 2508 // function template are combined with the set of non-template candidate 2509 // functions. 2510 TemplateDeductionInfo Info(Context); 2511 FunctionDecl *Specialization = 0; 2512 if (TemplateDeductionResult Result 2513 = DeduceTemplateArguments(FunctionTemplate, HasExplicitTemplateArgs, 2514 ExplicitTemplateArgs, NumExplicitTemplateArgs, 2515 Args, NumArgs, Specialization, Info)) { 2516 // FIXME: Record what happened with template argument deduction, so 2517 // that we can give the user a beautiful diagnostic. 2518 (void)Result; 2519 return; 2520 } 2521 2522 // Add the function template specialization produced by template argument 2523 // deduction as a candidate. 2524 assert(Specialization && "Missing function template specialization?"); 2525 AddOverloadCandidate(Specialization, Args, NumArgs, CandidateSet, 2526 SuppressUserConversions, ForceRValue); 2527} 2528 2529/// AddConversionCandidate - Add a C++ conversion function as a 2530/// candidate in the candidate set (C++ [over.match.conv], 2531/// C++ [over.match.copy]). From is the expression we're converting from, 2532/// and ToType is the type that we're eventually trying to convert to 2533/// (which may or may not be the same type as the type that the 2534/// conversion function produces). 2535void 2536Sema::AddConversionCandidate(CXXConversionDecl *Conversion, 2537 Expr *From, QualType ToType, 2538 OverloadCandidateSet& CandidateSet) { 2539 assert(!Conversion->getDescribedFunctionTemplate() && 2540 "Conversion function templates use AddTemplateConversionCandidate"); 2541 2542 if (!CandidateSet.isNewCandidate(Conversion)) 2543 return; 2544 2545 // Add this candidate 2546 CandidateSet.push_back(OverloadCandidate()); 2547 OverloadCandidate& Candidate = CandidateSet.back(); 2548 Candidate.Function = Conversion; 2549 Candidate.IsSurrogate = false; 2550 Candidate.IgnoreObjectArgument = false; 2551 Candidate.FinalConversion.setAsIdentityConversion(); 2552 Candidate.FinalConversion.FromTypePtr 2553 = Conversion->getConversionType().getAsOpaquePtr(); 2554 Candidate.FinalConversion.ToTypePtr = ToType.getAsOpaquePtr(); 2555 2556 // Determine the implicit conversion sequence for the implicit 2557 // object parameter. 2558 Candidate.Viable = true; 2559 Candidate.Conversions.resize(1); 2560 Candidate.Conversions[0] = TryObjectArgumentInitialization(From, Conversion); 2561 // Conversion functions to a different type in the base class is visible in 2562 // the derived class. So, a derived to base conversion should not participate 2563 // in overload resolution. 2564 if (Candidate.Conversions[0].Standard.Second == ICK_Derived_To_Base) 2565 Candidate.Conversions[0].Standard.Second = ICK_Identity; 2566 if (Candidate.Conversions[0].ConversionKind 2567 == ImplicitConversionSequence::BadConversion) { 2568 Candidate.Viable = false; 2569 return; 2570 } 2571 2572 // We won't go through a user-define type conversion function to convert a 2573 // derived to base as such conversions are given Conversion Rank. They only 2574 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user] 2575 QualType FromCanon 2576 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 2577 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 2578 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 2579 Candidate.Viable = false; 2580 return; 2581 } 2582 2583 2584 // To determine what the conversion from the result of calling the 2585 // conversion function to the type we're eventually trying to 2586 // convert to (ToType), we need to synthesize a call to the 2587 // conversion function and attempt copy initialization from it. This 2588 // makes sure that we get the right semantics with respect to 2589 // lvalues/rvalues and the type. Fortunately, we can allocate this 2590 // call on the stack and we don't need its arguments to be 2591 // well-formed. 2592 DeclRefExpr ConversionRef(Conversion, Conversion->getType(), 2593 SourceLocation()); 2594 ImplicitCastExpr ConversionFn(Context.getPointerType(Conversion->getType()), 2595 CastExpr::CK_FunctionToPointerDecay, 2596 &ConversionRef, false); 2597 2598 // Note that it is safe to allocate CallExpr on the stack here because 2599 // there are 0 arguments (i.e., nothing is allocated using ASTContext's 2600 // allocator). 2601 CallExpr Call(Context, &ConversionFn, 0, 0, 2602 Conversion->getConversionType().getNonReferenceType(), 2603 SourceLocation()); 2604 ImplicitConversionSequence ICS = 2605 TryCopyInitialization(&Call, ToType, 2606 /*SuppressUserConversions=*/true, 2607 /*ForceRValue=*/false, 2608 /*InOverloadResolution=*/false); 2609 2610 switch (ICS.ConversionKind) { 2611 case ImplicitConversionSequence::StandardConversion: 2612 Candidate.FinalConversion = ICS.Standard; 2613 break; 2614 2615 case ImplicitConversionSequence::BadConversion: 2616 Candidate.Viable = false; 2617 break; 2618 2619 default: 2620 assert(false && 2621 "Can only end up with a standard conversion sequence or failure"); 2622 } 2623} 2624 2625/// \brief Adds a conversion function template specialization 2626/// candidate to the overload set, using template argument deduction 2627/// to deduce the template arguments of the conversion function 2628/// template from the type that we are converting to (C++ 2629/// [temp.deduct.conv]). 2630void 2631Sema::AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate, 2632 Expr *From, QualType ToType, 2633 OverloadCandidateSet &CandidateSet) { 2634 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) && 2635 "Only conversion function templates permitted here"); 2636 2637 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 2638 return; 2639 2640 TemplateDeductionInfo Info(Context); 2641 CXXConversionDecl *Specialization = 0; 2642 if (TemplateDeductionResult Result 2643 = DeduceTemplateArguments(FunctionTemplate, ToType, 2644 Specialization, Info)) { 2645 // FIXME: Record what happened with template argument deduction, so 2646 // that we can give the user a beautiful diagnostic. 2647 (void)Result; 2648 return; 2649 } 2650 2651 // Add the conversion function template specialization produced by 2652 // template argument deduction as a candidate. 2653 assert(Specialization && "Missing function template specialization?"); 2654 AddConversionCandidate(Specialization, From, ToType, CandidateSet); 2655} 2656 2657/// AddSurrogateCandidate - Adds a "surrogate" candidate function that 2658/// converts the given @c Object to a function pointer via the 2659/// conversion function @c Conversion, and then attempts to call it 2660/// with the given arguments (C++ [over.call.object]p2-4). Proto is 2661/// the type of function that we'll eventually be calling. 2662void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion, 2663 const FunctionProtoType *Proto, 2664 Expr *Object, Expr **Args, unsigned NumArgs, 2665 OverloadCandidateSet& CandidateSet) { 2666 if (!CandidateSet.isNewCandidate(Conversion)) 2667 return; 2668 2669 CandidateSet.push_back(OverloadCandidate()); 2670 OverloadCandidate& Candidate = CandidateSet.back(); 2671 Candidate.Function = 0; 2672 Candidate.Surrogate = Conversion; 2673 Candidate.Viable = true; 2674 Candidate.IsSurrogate = true; 2675 Candidate.IgnoreObjectArgument = false; 2676 Candidate.Conversions.resize(NumArgs + 1); 2677 2678 // Determine the implicit conversion sequence for the implicit 2679 // object parameter. 2680 ImplicitConversionSequence ObjectInit 2681 = TryObjectArgumentInitialization(Object, Conversion); 2682 if (ObjectInit.ConversionKind == ImplicitConversionSequence::BadConversion) { 2683 Candidate.Viable = false; 2684 return; 2685 } 2686 2687 // The first conversion is actually a user-defined conversion whose 2688 // first conversion is ObjectInit's standard conversion (which is 2689 // effectively a reference binding). Record it as such. 2690 Candidate.Conversions[0].ConversionKind 2691 = ImplicitConversionSequence::UserDefinedConversion; 2692 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard; 2693 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion; 2694 Candidate.Conversions[0].UserDefined.After 2695 = Candidate.Conversions[0].UserDefined.Before; 2696 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion(); 2697 2698 // Find the 2699 unsigned NumArgsInProto = Proto->getNumArgs(); 2700 2701 // (C++ 13.3.2p2): A candidate function having fewer than m 2702 // parameters is viable only if it has an ellipsis in its parameter 2703 // list (8.3.5). 2704 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 2705 Candidate.Viable = false; 2706 return; 2707 } 2708 2709 // Function types don't have any default arguments, so just check if 2710 // we have enough arguments. 2711 if (NumArgs < NumArgsInProto) { 2712 // Not enough arguments. 2713 Candidate.Viable = false; 2714 return; 2715 } 2716 2717 // Determine the implicit conversion sequences for each of the 2718 // arguments. 2719 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 2720 if (ArgIdx < NumArgsInProto) { 2721 // (C++ 13.3.2p3): for F to be a viable function, there shall 2722 // exist for each argument an implicit conversion sequence 2723 // (13.3.3.1) that converts that argument to the corresponding 2724 // parameter of F. 2725 QualType ParamType = Proto->getArgType(ArgIdx); 2726 Candidate.Conversions[ArgIdx + 1] 2727 = TryCopyInitialization(Args[ArgIdx], ParamType, 2728 /*SuppressUserConversions=*/false, 2729 /*ForceRValue=*/false, 2730 /*InOverloadResolution=*/false); 2731 if (Candidate.Conversions[ArgIdx + 1].ConversionKind 2732 == ImplicitConversionSequence::BadConversion) { 2733 Candidate.Viable = false; 2734 break; 2735 } 2736 } else { 2737 // (C++ 13.3.2p2): For the purposes of overload resolution, any 2738 // argument for which there is no corresponding parameter is 2739 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 2740 Candidate.Conversions[ArgIdx + 1].ConversionKind 2741 = ImplicitConversionSequence::EllipsisConversion; 2742 } 2743 } 2744} 2745 2746// FIXME: This will eventually be removed, once we've migrated all of the 2747// operator overloading logic over to the scheme used by binary operators, which 2748// works for template instantiation. 2749void Sema::AddOperatorCandidates(OverloadedOperatorKind Op, Scope *S, 2750 SourceLocation OpLoc, 2751 Expr **Args, unsigned NumArgs, 2752 OverloadCandidateSet& CandidateSet, 2753 SourceRange OpRange) { 2754 FunctionSet Functions; 2755 2756 QualType T1 = Args[0]->getType(); 2757 QualType T2; 2758 if (NumArgs > 1) 2759 T2 = Args[1]->getType(); 2760 2761 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 2762 if (S) 2763 LookupOverloadedOperatorName(Op, S, T1, T2, Functions); 2764 ArgumentDependentLookup(OpName, /*Operator*/true, Args, NumArgs, Functions); 2765 AddFunctionCandidates(Functions, Args, NumArgs, CandidateSet); 2766 AddMemberOperatorCandidates(Op, OpLoc, Args, NumArgs, CandidateSet, OpRange); 2767 AddBuiltinOperatorCandidates(Op, OpLoc, Args, NumArgs, CandidateSet); 2768} 2769 2770/// \brief Add overload candidates for overloaded operators that are 2771/// member functions. 2772/// 2773/// Add the overloaded operator candidates that are member functions 2774/// for the operator Op that was used in an operator expression such 2775/// as "x Op y". , Args/NumArgs provides the operator arguments, and 2776/// CandidateSet will store the added overload candidates. (C++ 2777/// [over.match.oper]). 2778void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op, 2779 SourceLocation OpLoc, 2780 Expr **Args, unsigned NumArgs, 2781 OverloadCandidateSet& CandidateSet, 2782 SourceRange OpRange) { 2783 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 2784 2785 // C++ [over.match.oper]p3: 2786 // For a unary operator @ with an operand of a type whose 2787 // cv-unqualified version is T1, and for a binary operator @ with 2788 // a left operand of a type whose cv-unqualified version is T1 and 2789 // a right operand of a type whose cv-unqualified version is T2, 2790 // three sets of candidate functions, designated member 2791 // candidates, non-member candidates and built-in candidates, are 2792 // constructed as follows: 2793 QualType T1 = Args[0]->getType(); 2794 QualType T2; 2795 if (NumArgs > 1) 2796 T2 = Args[1]->getType(); 2797 2798 // -- If T1 is a class type, the set of member candidates is the 2799 // result of the qualified lookup of T1::operator@ 2800 // (13.3.1.1.1); otherwise, the set of member candidates is 2801 // empty. 2802 if (const RecordType *T1Rec = T1->getAs<RecordType>()) { 2803 // Complete the type if it can be completed. Otherwise, we're done. 2804 if (RequireCompleteType(OpLoc, T1, PDiag())) 2805 return; 2806 2807 LookupResult Operators; 2808 LookupQualifiedName(Operators, T1Rec->getDecl(), OpName, 2809 LookupOrdinaryName, false); 2810 for (LookupResult::iterator Oper = Operators.begin(), 2811 OperEnd = Operators.end(); 2812 Oper != OperEnd; 2813 ++Oper) { 2814 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*Oper)) { 2815 AddMethodCandidate(Method, Args[0], Args+1, NumArgs - 1, CandidateSet, 2816 /*SuppressUserConversions=*/false); 2817 continue; 2818 } 2819 2820 assert(isa<FunctionTemplateDecl>(*Oper) && 2821 isa<CXXMethodDecl>(cast<FunctionTemplateDecl>(*Oper) 2822 ->getTemplatedDecl()) && 2823 "Expected a member function template"); 2824 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(*Oper), false, 0, 0, 2825 Args[0], Args+1, NumArgs - 1, CandidateSet, 2826 /*SuppressUserConversions=*/false); 2827 } 2828 } 2829} 2830 2831/// AddBuiltinCandidate - Add a candidate for a built-in 2832/// operator. ResultTy and ParamTys are the result and parameter types 2833/// of the built-in candidate, respectively. Args and NumArgs are the 2834/// arguments being passed to the candidate. IsAssignmentOperator 2835/// should be true when this built-in candidate is an assignment 2836/// operator. NumContextualBoolArguments is the number of arguments 2837/// (at the beginning of the argument list) that will be contextually 2838/// converted to bool. 2839void Sema::AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys, 2840 Expr **Args, unsigned NumArgs, 2841 OverloadCandidateSet& CandidateSet, 2842 bool IsAssignmentOperator, 2843 unsigned NumContextualBoolArguments) { 2844 // Add this candidate 2845 CandidateSet.push_back(OverloadCandidate()); 2846 OverloadCandidate& Candidate = CandidateSet.back(); 2847 Candidate.Function = 0; 2848 Candidate.IsSurrogate = false; 2849 Candidate.IgnoreObjectArgument = false; 2850 Candidate.BuiltinTypes.ResultTy = ResultTy; 2851 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 2852 Candidate.BuiltinTypes.ParamTypes[ArgIdx] = ParamTys[ArgIdx]; 2853 2854 // Determine the implicit conversion sequences for each of the 2855 // arguments. 2856 Candidate.Viable = true; 2857 Candidate.Conversions.resize(NumArgs); 2858 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 2859 // C++ [over.match.oper]p4: 2860 // For the built-in assignment operators, conversions of the 2861 // left operand are restricted as follows: 2862 // -- no temporaries are introduced to hold the left operand, and 2863 // -- no user-defined conversions are applied to the left 2864 // operand to achieve a type match with the left-most 2865 // parameter of a built-in candidate. 2866 // 2867 // We block these conversions by turning off user-defined 2868 // conversions, since that is the only way that initialization of 2869 // a reference to a non-class type can occur from something that 2870 // is not of the same type. 2871 if (ArgIdx < NumContextualBoolArguments) { 2872 assert(ParamTys[ArgIdx] == Context.BoolTy && 2873 "Contextual conversion to bool requires bool type"); 2874 Candidate.Conversions[ArgIdx] = TryContextuallyConvertToBool(Args[ArgIdx]); 2875 } else { 2876 Candidate.Conversions[ArgIdx] 2877 = TryCopyInitialization(Args[ArgIdx], ParamTys[ArgIdx], 2878 ArgIdx == 0 && IsAssignmentOperator, 2879 /*ForceRValue=*/false, 2880 /*InOverloadResolution=*/false); 2881 } 2882 if (Candidate.Conversions[ArgIdx].ConversionKind 2883 == ImplicitConversionSequence::BadConversion) { 2884 Candidate.Viable = false; 2885 break; 2886 } 2887 } 2888} 2889 2890/// BuiltinCandidateTypeSet - A set of types that will be used for the 2891/// candidate operator functions for built-in operators (C++ 2892/// [over.built]). The types are separated into pointer types and 2893/// enumeration types. 2894class BuiltinCandidateTypeSet { 2895 /// TypeSet - A set of types. 2896 typedef llvm::SmallPtrSet<QualType, 8> TypeSet; 2897 2898 /// PointerTypes - The set of pointer types that will be used in the 2899 /// built-in candidates. 2900 TypeSet PointerTypes; 2901 2902 /// MemberPointerTypes - The set of member pointer types that will be 2903 /// used in the built-in candidates. 2904 TypeSet MemberPointerTypes; 2905 2906 /// EnumerationTypes - The set of enumeration types that will be 2907 /// used in the built-in candidates. 2908 TypeSet EnumerationTypes; 2909 2910 /// Sema - The semantic analysis instance where we are building the 2911 /// candidate type set. 2912 Sema &SemaRef; 2913 2914 /// Context - The AST context in which we will build the type sets. 2915 ASTContext &Context; 2916 2917 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 2918 const Qualifiers &VisibleQuals); 2919 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty); 2920 2921public: 2922 /// iterator - Iterates through the types that are part of the set. 2923 typedef TypeSet::iterator iterator; 2924 2925 BuiltinCandidateTypeSet(Sema &SemaRef) 2926 : SemaRef(SemaRef), Context(SemaRef.Context) { } 2927 2928 void AddTypesConvertedFrom(QualType Ty, 2929 SourceLocation Loc, 2930 bool AllowUserConversions, 2931 bool AllowExplicitConversions, 2932 const Qualifiers &VisibleTypeConversionsQuals); 2933 2934 /// pointer_begin - First pointer type found; 2935 iterator pointer_begin() { return PointerTypes.begin(); } 2936 2937 /// pointer_end - Past the last pointer type found; 2938 iterator pointer_end() { return PointerTypes.end(); } 2939 2940 /// member_pointer_begin - First member pointer type found; 2941 iterator member_pointer_begin() { return MemberPointerTypes.begin(); } 2942 2943 /// member_pointer_end - Past the last member pointer type found; 2944 iterator member_pointer_end() { return MemberPointerTypes.end(); } 2945 2946 /// enumeration_begin - First enumeration type found; 2947 iterator enumeration_begin() { return EnumerationTypes.begin(); } 2948 2949 /// enumeration_end - Past the last enumeration type found; 2950 iterator enumeration_end() { return EnumerationTypes.end(); } 2951}; 2952 2953/// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to 2954/// the set of pointer types along with any more-qualified variants of 2955/// that type. For example, if @p Ty is "int const *", this routine 2956/// will add "int const *", "int const volatile *", "int const 2957/// restrict *", and "int const volatile restrict *" to the set of 2958/// pointer types. Returns true if the add of @p Ty itself succeeded, 2959/// false otherwise. 2960/// 2961/// FIXME: what to do about extended qualifiers? 2962bool 2963BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 2964 const Qualifiers &VisibleQuals) { 2965 2966 // Insert this type. 2967 if (!PointerTypes.insert(Ty)) 2968 return false; 2969 2970 const PointerType *PointerTy = Ty->getAs<PointerType>(); 2971 assert(PointerTy && "type was not a pointer type!"); 2972 2973 QualType PointeeTy = PointerTy->getPointeeType(); 2974 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 2975 bool hasVolatile = VisibleQuals.hasVolatile(); 2976 bool hasRestrict = VisibleQuals.hasRestrict(); 2977 2978 // Iterate through all strict supersets of BaseCVR. 2979 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 2980 if ((CVR | BaseCVR) != CVR) continue; 2981 // Skip over Volatile/Restrict if no Volatile/Restrict found anywhere 2982 // in the types. 2983 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue; 2984 if ((CVR & Qualifiers::Restrict) && !hasRestrict) continue; 2985 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 2986 PointerTypes.insert(Context.getPointerType(QPointeeTy)); 2987 } 2988 2989 return true; 2990} 2991 2992/// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty 2993/// to the set of pointer types along with any more-qualified variants of 2994/// that type. For example, if @p Ty is "int const *", this routine 2995/// will add "int const *", "int const volatile *", "int const 2996/// restrict *", and "int const volatile restrict *" to the set of 2997/// pointer types. Returns true if the add of @p Ty itself succeeded, 2998/// false otherwise. 2999/// 3000/// FIXME: what to do about extended qualifiers? 3001bool 3002BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants( 3003 QualType Ty) { 3004 // Insert this type. 3005 if (!MemberPointerTypes.insert(Ty)) 3006 return false; 3007 3008 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>(); 3009 assert(PointerTy && "type was not a member pointer type!"); 3010 3011 QualType PointeeTy = PointerTy->getPointeeType(); 3012 const Type *ClassTy = PointerTy->getClass(); 3013 3014 // Iterate through all strict supersets of the pointee type's CVR 3015 // qualifiers. 3016 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 3017 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 3018 if ((CVR | BaseCVR) != CVR) continue; 3019 3020 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 3021 MemberPointerTypes.insert(Context.getMemberPointerType(QPointeeTy, ClassTy)); 3022 } 3023 3024 return true; 3025} 3026 3027/// AddTypesConvertedFrom - Add each of the types to which the type @p 3028/// Ty can be implicit converted to the given set of @p Types. We're 3029/// primarily interested in pointer types and enumeration types. We also 3030/// take member pointer types, for the conditional operator. 3031/// AllowUserConversions is true if we should look at the conversion 3032/// functions of a class type, and AllowExplicitConversions if we 3033/// should also include the explicit conversion functions of a class 3034/// type. 3035void 3036BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty, 3037 SourceLocation Loc, 3038 bool AllowUserConversions, 3039 bool AllowExplicitConversions, 3040 const Qualifiers &VisibleQuals) { 3041 // Only deal with canonical types. 3042 Ty = Context.getCanonicalType(Ty); 3043 3044 // Look through reference types; they aren't part of the type of an 3045 // expression for the purposes of conversions. 3046 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>()) 3047 Ty = RefTy->getPointeeType(); 3048 3049 // We don't care about qualifiers on the type. 3050 Ty = Ty.getUnqualifiedType(); 3051 3052 if (const PointerType *PointerTy = Ty->getAs<PointerType>()) { 3053 QualType PointeeTy = PointerTy->getPointeeType(); 3054 3055 // Insert our type, and its more-qualified variants, into the set 3056 // of types. 3057 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals)) 3058 return; 3059 } else if (Ty->isMemberPointerType()) { 3060 // Member pointers are far easier, since the pointee can't be converted. 3061 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty)) 3062 return; 3063 } else if (Ty->isEnumeralType()) { 3064 EnumerationTypes.insert(Ty); 3065 } else if (AllowUserConversions) { 3066 if (const RecordType *TyRec = Ty->getAs<RecordType>()) { 3067 if (SemaRef.RequireCompleteType(Loc, Ty, 0)) { 3068 // No conversion functions in incomplete types. 3069 return; 3070 } 3071 3072 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 3073 OverloadedFunctionDecl *Conversions 3074 = ClassDecl->getVisibleConversionFunctions(); 3075 for (OverloadedFunctionDecl::function_iterator Func 3076 = Conversions->function_begin(); 3077 Func != Conversions->function_end(); ++Func) { 3078 CXXConversionDecl *Conv; 3079 FunctionTemplateDecl *ConvTemplate; 3080 GetFunctionAndTemplate(*Func, Conv, ConvTemplate); 3081 3082 // Skip conversion function templates; they don't tell us anything 3083 // about which builtin types we can convert to. 3084 if (ConvTemplate) 3085 continue; 3086 3087 if (AllowExplicitConversions || !Conv->isExplicit()) { 3088 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false, 3089 VisibleQuals); 3090 } 3091 } 3092 } 3093 } 3094} 3095 3096/// \brief Helper function for AddBuiltinOperatorCandidates() that adds 3097/// the volatile- and non-volatile-qualified assignment operators for the 3098/// given type to the candidate set. 3099static void AddBuiltinAssignmentOperatorCandidates(Sema &S, 3100 QualType T, 3101 Expr **Args, 3102 unsigned NumArgs, 3103 OverloadCandidateSet &CandidateSet) { 3104 QualType ParamTypes[2]; 3105 3106 // T& operator=(T&, T) 3107 ParamTypes[0] = S.Context.getLValueReferenceType(T); 3108 ParamTypes[1] = T; 3109 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 3110 /*IsAssignmentOperator=*/true); 3111 3112 if (!S.Context.getCanonicalType(T).isVolatileQualified()) { 3113 // volatile T& operator=(volatile T&, T) 3114 ParamTypes[0] 3115 = S.Context.getLValueReferenceType(S.Context.getVolatileType(T)); 3116 ParamTypes[1] = T; 3117 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 3118 /*IsAssignmentOperator=*/true); 3119 } 3120} 3121 3122/// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers 3123/// , if any, found in visible type conversion functions found in ArgExpr's 3124/// type. 3125static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) { 3126 Qualifiers VRQuals; 3127 const RecordType *TyRec; 3128 if (const MemberPointerType *RHSMPType = 3129 ArgExpr->getType()->getAs<MemberPointerType>()) 3130 TyRec = cast<RecordType>(RHSMPType->getClass()); 3131 else 3132 TyRec = ArgExpr->getType()->getAs<RecordType>(); 3133 if (!TyRec) { 3134 // Just to be safe, assume the worst case. 3135 VRQuals.addVolatile(); 3136 VRQuals.addRestrict(); 3137 return VRQuals; 3138 } 3139 3140 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 3141 OverloadedFunctionDecl *Conversions = 3142 ClassDecl->getVisibleConversionFunctions(); 3143 3144 for (OverloadedFunctionDecl::function_iterator Func 3145 = Conversions->function_begin(); 3146 Func != Conversions->function_end(); ++Func) { 3147 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(*Func)) { 3148 QualType CanTy = Context.getCanonicalType(Conv->getConversionType()); 3149 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>()) 3150 CanTy = ResTypeRef->getPointeeType(); 3151 // Need to go down the pointer/mempointer chain and add qualifiers 3152 // as see them. 3153 bool done = false; 3154 while (!done) { 3155 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>()) 3156 CanTy = ResTypePtr->getPointeeType(); 3157 else if (const MemberPointerType *ResTypeMPtr = 3158 CanTy->getAs<MemberPointerType>()) 3159 CanTy = ResTypeMPtr->getPointeeType(); 3160 else 3161 done = true; 3162 if (CanTy.isVolatileQualified()) 3163 VRQuals.addVolatile(); 3164 if (CanTy.isRestrictQualified()) 3165 VRQuals.addRestrict(); 3166 if (VRQuals.hasRestrict() && VRQuals.hasVolatile()) 3167 return VRQuals; 3168 } 3169 } 3170 } 3171 return VRQuals; 3172} 3173 3174/// AddBuiltinOperatorCandidates - Add the appropriate built-in 3175/// operator overloads to the candidate set (C++ [over.built]), based 3176/// on the operator @p Op and the arguments given. For example, if the 3177/// operator is a binary '+', this routine might add "int 3178/// operator+(int, int)" to cover integer addition. 3179void 3180Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op, 3181 SourceLocation OpLoc, 3182 Expr **Args, unsigned NumArgs, 3183 OverloadCandidateSet& CandidateSet) { 3184 // The set of "promoted arithmetic types", which are the arithmetic 3185 // types are that preserved by promotion (C++ [over.built]p2). Note 3186 // that the first few of these types are the promoted integral 3187 // types; these types need to be first. 3188 // FIXME: What about complex? 3189 const unsigned FirstIntegralType = 0; 3190 const unsigned LastIntegralType = 13; 3191 const unsigned FirstPromotedIntegralType = 7, 3192 LastPromotedIntegralType = 13; 3193 const unsigned FirstPromotedArithmeticType = 7, 3194 LastPromotedArithmeticType = 16; 3195 const unsigned NumArithmeticTypes = 16; 3196 QualType ArithmeticTypes[NumArithmeticTypes] = { 3197 Context.BoolTy, Context.CharTy, Context.WCharTy, 3198// FIXME: Context.Char16Ty, Context.Char32Ty, 3199 Context.SignedCharTy, Context.ShortTy, 3200 Context.UnsignedCharTy, Context.UnsignedShortTy, 3201 Context.IntTy, Context.LongTy, Context.LongLongTy, 3202 Context.UnsignedIntTy, Context.UnsignedLongTy, Context.UnsignedLongLongTy, 3203 Context.FloatTy, Context.DoubleTy, Context.LongDoubleTy 3204 }; 3205 assert(ArithmeticTypes[FirstPromotedIntegralType] == Context.IntTy && 3206 "Invalid first promoted integral type"); 3207 assert(ArithmeticTypes[LastPromotedIntegralType - 1] 3208 == Context.UnsignedLongLongTy && 3209 "Invalid last promoted integral type"); 3210 assert(ArithmeticTypes[FirstPromotedArithmeticType] == Context.IntTy && 3211 "Invalid first promoted arithmetic type"); 3212 assert(ArithmeticTypes[LastPromotedArithmeticType - 1] 3213 == Context.LongDoubleTy && 3214 "Invalid last promoted arithmetic type"); 3215 3216 // Find all of the types that the arguments can convert to, but only 3217 // if the operator we're looking at has built-in operator candidates 3218 // that make use of these types. 3219 Qualifiers VisibleTypeConversionsQuals; 3220 VisibleTypeConversionsQuals.addConst(); 3221 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 3222 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]); 3223 3224 BuiltinCandidateTypeSet CandidateTypes(*this); 3225 if (Op == OO_Less || Op == OO_Greater || Op == OO_LessEqual || 3226 Op == OO_GreaterEqual || Op == OO_EqualEqual || Op == OO_ExclaimEqual || 3227 Op == OO_Plus || (Op == OO_Minus && NumArgs == 2) || Op == OO_Equal || 3228 Op == OO_PlusEqual || Op == OO_MinusEqual || Op == OO_Subscript || 3229 Op == OO_ArrowStar || Op == OO_PlusPlus || Op == OO_MinusMinus || 3230 (Op == OO_Star && NumArgs == 1) || Op == OO_Conditional) { 3231 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 3232 CandidateTypes.AddTypesConvertedFrom(Args[ArgIdx]->getType(), 3233 OpLoc, 3234 true, 3235 (Op == OO_Exclaim || 3236 Op == OO_AmpAmp || 3237 Op == OO_PipePipe), 3238 VisibleTypeConversionsQuals); 3239 } 3240 3241 bool isComparison = false; 3242 switch (Op) { 3243 case OO_None: 3244 case NUM_OVERLOADED_OPERATORS: 3245 assert(false && "Expected an overloaded operator"); 3246 break; 3247 3248 case OO_Star: // '*' is either unary or binary 3249 if (NumArgs == 1) 3250 goto UnaryStar; 3251 else 3252 goto BinaryStar; 3253 break; 3254 3255 case OO_Plus: // '+' is either unary or binary 3256 if (NumArgs == 1) 3257 goto UnaryPlus; 3258 else 3259 goto BinaryPlus; 3260 break; 3261 3262 case OO_Minus: // '-' is either unary or binary 3263 if (NumArgs == 1) 3264 goto UnaryMinus; 3265 else 3266 goto BinaryMinus; 3267 break; 3268 3269 case OO_Amp: // '&' is either unary or binary 3270 if (NumArgs == 1) 3271 goto UnaryAmp; 3272 else 3273 goto BinaryAmp; 3274 3275 case OO_PlusPlus: 3276 case OO_MinusMinus: 3277 // C++ [over.built]p3: 3278 // 3279 // For every pair (T, VQ), where T is an arithmetic type, and VQ 3280 // is either volatile or empty, there exist candidate operator 3281 // functions of the form 3282 // 3283 // VQ T& operator++(VQ T&); 3284 // T operator++(VQ T&, int); 3285 // 3286 // C++ [over.built]p4: 3287 // 3288 // For every pair (T, VQ), where T is an arithmetic type other 3289 // than bool, and VQ is either volatile or empty, there exist 3290 // candidate operator functions of the form 3291 // 3292 // VQ T& operator--(VQ T&); 3293 // T operator--(VQ T&, int); 3294 for (unsigned Arith = (Op == OO_PlusPlus? 0 : 1); 3295 Arith < NumArithmeticTypes; ++Arith) { 3296 QualType ArithTy = ArithmeticTypes[Arith]; 3297 QualType ParamTypes[2] 3298 = { Context.getLValueReferenceType(ArithTy), Context.IntTy }; 3299 3300 // Non-volatile version. 3301 if (NumArgs == 1) 3302 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 3303 else 3304 AddBuiltinCandidate(ArithTy, ParamTypes, Args, 2, CandidateSet); 3305 // heuristic to reduce number of builtin candidates in the set. 3306 // Add volatile version only if there are conversions to a volatile type. 3307 if (VisibleTypeConversionsQuals.hasVolatile()) { 3308 // Volatile version 3309 ParamTypes[0] 3310 = Context.getLValueReferenceType(Context.getVolatileType(ArithTy)); 3311 if (NumArgs == 1) 3312 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 3313 else 3314 AddBuiltinCandidate(ArithTy, ParamTypes, Args, 2, CandidateSet); 3315 } 3316 } 3317 3318 // C++ [over.built]p5: 3319 // 3320 // For every pair (T, VQ), where T is a cv-qualified or 3321 // cv-unqualified object type, and VQ is either volatile or 3322 // empty, there exist candidate operator functions of the form 3323 // 3324 // T*VQ& operator++(T*VQ&); 3325 // T*VQ& operator--(T*VQ&); 3326 // T* operator++(T*VQ&, int); 3327 // T* operator--(T*VQ&, int); 3328 for (BuiltinCandidateTypeSet::iterator Ptr = CandidateTypes.pointer_begin(); 3329 Ptr != CandidateTypes.pointer_end(); ++Ptr) { 3330 // Skip pointer types that aren't pointers to object types. 3331 if (!(*Ptr)->getAs<PointerType>()->getPointeeType()->isObjectType()) 3332 continue; 3333 3334 QualType ParamTypes[2] = { 3335 Context.getLValueReferenceType(*Ptr), Context.IntTy 3336 }; 3337 3338 // Without volatile 3339 if (NumArgs == 1) 3340 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 3341 else 3342 AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 3343 3344 if (!Context.getCanonicalType(*Ptr).isVolatileQualified() && 3345 VisibleTypeConversionsQuals.hasVolatile()) { 3346 // With volatile 3347 ParamTypes[0] 3348 = Context.getLValueReferenceType(Context.getVolatileType(*Ptr)); 3349 if (NumArgs == 1) 3350 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 3351 else 3352 AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 3353 } 3354 } 3355 break; 3356 3357 UnaryStar: 3358 // C++ [over.built]p6: 3359 // For every cv-qualified or cv-unqualified object type T, there 3360 // exist candidate operator functions of the form 3361 // 3362 // T& operator*(T*); 3363 // 3364 // C++ [over.built]p7: 3365 // For every function type T, there exist candidate operator 3366 // functions of the form 3367 // T& operator*(T*); 3368 for (BuiltinCandidateTypeSet::iterator Ptr = CandidateTypes.pointer_begin(); 3369 Ptr != CandidateTypes.pointer_end(); ++Ptr) { 3370 QualType ParamTy = *Ptr; 3371 QualType PointeeTy = ParamTy->getAs<PointerType>()->getPointeeType(); 3372 AddBuiltinCandidate(Context.getLValueReferenceType(PointeeTy), 3373 &ParamTy, Args, 1, CandidateSet); 3374 } 3375 break; 3376 3377 UnaryPlus: 3378 // C++ [over.built]p8: 3379 // For every type T, there exist candidate operator functions of 3380 // the form 3381 // 3382 // T* operator+(T*); 3383 for (BuiltinCandidateTypeSet::iterator Ptr = CandidateTypes.pointer_begin(); 3384 Ptr != CandidateTypes.pointer_end(); ++Ptr) { 3385 QualType ParamTy = *Ptr; 3386 AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet); 3387 } 3388 3389 // Fall through 3390 3391 UnaryMinus: 3392 // C++ [over.built]p9: 3393 // For every promoted arithmetic type T, there exist candidate 3394 // operator functions of the form 3395 // 3396 // T operator+(T); 3397 // T operator-(T); 3398 for (unsigned Arith = FirstPromotedArithmeticType; 3399 Arith < LastPromotedArithmeticType; ++Arith) { 3400 QualType ArithTy = ArithmeticTypes[Arith]; 3401 AddBuiltinCandidate(ArithTy, &ArithTy, Args, 1, CandidateSet); 3402 } 3403 break; 3404 3405 case OO_Tilde: 3406 // C++ [over.built]p10: 3407 // For every promoted integral type T, there exist candidate 3408 // operator functions of the form 3409 // 3410 // T operator~(T); 3411 for (unsigned Int = FirstPromotedIntegralType; 3412 Int < LastPromotedIntegralType; ++Int) { 3413 QualType IntTy = ArithmeticTypes[Int]; 3414 AddBuiltinCandidate(IntTy, &IntTy, Args, 1, CandidateSet); 3415 } 3416 break; 3417 3418 case OO_New: 3419 case OO_Delete: 3420 case OO_Array_New: 3421 case OO_Array_Delete: 3422 case OO_Call: 3423 assert(false && "Special operators don't use AddBuiltinOperatorCandidates"); 3424 break; 3425 3426 case OO_Comma: 3427 UnaryAmp: 3428 case OO_Arrow: 3429 // C++ [over.match.oper]p3: 3430 // -- For the operator ',', the unary operator '&', or the 3431 // operator '->', the built-in candidates set is empty. 3432 break; 3433 3434 case OO_EqualEqual: 3435 case OO_ExclaimEqual: 3436 // C++ [over.match.oper]p16: 3437 // For every pointer to member type T, there exist candidate operator 3438 // functions of the form 3439 // 3440 // bool operator==(T,T); 3441 // bool operator!=(T,T); 3442 for (BuiltinCandidateTypeSet::iterator 3443 MemPtr = CandidateTypes.member_pointer_begin(), 3444 MemPtrEnd = CandidateTypes.member_pointer_end(); 3445 MemPtr != MemPtrEnd; 3446 ++MemPtr) { 3447 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 3448 AddBuiltinCandidate(Context.BoolTy, ParamTypes, Args, 2, CandidateSet); 3449 } 3450 3451 // Fall through 3452 3453 case OO_Less: 3454 case OO_Greater: 3455 case OO_LessEqual: 3456 case OO_GreaterEqual: 3457 // C++ [over.built]p15: 3458 // 3459 // For every pointer or enumeration type T, there exist 3460 // candidate operator functions of the form 3461 // 3462 // bool operator<(T, T); 3463 // bool operator>(T, T); 3464 // bool operator<=(T, T); 3465 // bool operator>=(T, T); 3466 // bool operator==(T, T); 3467 // bool operator!=(T, T); 3468 for (BuiltinCandidateTypeSet::iterator Ptr = CandidateTypes.pointer_begin(); 3469 Ptr != CandidateTypes.pointer_end(); ++Ptr) { 3470 QualType ParamTypes[2] = { *Ptr, *Ptr }; 3471 AddBuiltinCandidate(Context.BoolTy, ParamTypes, Args, 2, CandidateSet); 3472 } 3473 for (BuiltinCandidateTypeSet::iterator Enum 3474 = CandidateTypes.enumeration_begin(); 3475 Enum != CandidateTypes.enumeration_end(); ++Enum) { 3476 QualType ParamTypes[2] = { *Enum, *Enum }; 3477 AddBuiltinCandidate(Context.BoolTy, ParamTypes, Args, 2, CandidateSet); 3478 } 3479 3480 // Fall through. 3481 isComparison = true; 3482 3483 BinaryPlus: 3484 BinaryMinus: 3485 if (!isComparison) { 3486 // We didn't fall through, so we must have OO_Plus or OO_Minus. 3487 3488 // C++ [over.built]p13: 3489 // 3490 // For every cv-qualified or cv-unqualified object type T 3491 // there exist candidate operator functions of the form 3492 // 3493 // T* operator+(T*, ptrdiff_t); 3494 // T& operator[](T*, ptrdiff_t); [BELOW] 3495 // T* operator-(T*, ptrdiff_t); 3496 // T* operator+(ptrdiff_t, T*); 3497 // T& operator[](ptrdiff_t, T*); [BELOW] 3498 // 3499 // C++ [over.built]p14: 3500 // 3501 // For every T, where T is a pointer to object type, there 3502 // exist candidate operator functions of the form 3503 // 3504 // ptrdiff_t operator-(T, T); 3505 for (BuiltinCandidateTypeSet::iterator Ptr 3506 = CandidateTypes.pointer_begin(); 3507 Ptr != CandidateTypes.pointer_end(); ++Ptr) { 3508 QualType ParamTypes[2] = { *Ptr, Context.getPointerDiffType() }; 3509 3510 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t) 3511 AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 3512 3513 if (Op == OO_Plus) { 3514 // T* operator+(ptrdiff_t, T*); 3515 ParamTypes[0] = ParamTypes[1]; 3516 ParamTypes[1] = *Ptr; 3517 AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 3518 } else { 3519 // ptrdiff_t operator-(T, T); 3520 ParamTypes[1] = *Ptr; 3521 AddBuiltinCandidate(Context.getPointerDiffType(), ParamTypes, 3522 Args, 2, CandidateSet); 3523 } 3524 } 3525 } 3526 // Fall through 3527 3528 case OO_Slash: 3529 BinaryStar: 3530 Conditional: 3531 // C++ [over.built]p12: 3532 // 3533 // For every pair of promoted arithmetic types L and R, there 3534 // exist candidate operator functions of the form 3535 // 3536 // LR operator*(L, R); 3537 // LR operator/(L, R); 3538 // LR operator+(L, R); 3539 // LR operator-(L, R); 3540 // bool operator<(L, R); 3541 // bool operator>(L, R); 3542 // bool operator<=(L, R); 3543 // bool operator>=(L, R); 3544 // bool operator==(L, R); 3545 // bool operator!=(L, R); 3546 // 3547 // where LR is the result of the usual arithmetic conversions 3548 // between types L and R. 3549 // 3550 // C++ [over.built]p24: 3551 // 3552 // For every pair of promoted arithmetic types L and R, there exist 3553 // candidate operator functions of the form 3554 // 3555 // LR operator?(bool, L, R); 3556 // 3557 // where LR is the result of the usual arithmetic conversions 3558 // between types L and R. 3559 // Our candidates ignore the first parameter. 3560 for (unsigned Left = FirstPromotedArithmeticType; 3561 Left < LastPromotedArithmeticType; ++Left) { 3562 for (unsigned Right = FirstPromotedArithmeticType; 3563 Right < LastPromotedArithmeticType; ++Right) { 3564 QualType LandR[2] = { ArithmeticTypes[Left], ArithmeticTypes[Right] }; 3565 QualType Result 3566 = isComparison 3567 ? Context.BoolTy 3568 : Context.UsualArithmeticConversionsType(LandR[0], LandR[1]); 3569 AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 3570 } 3571 } 3572 break; 3573 3574 case OO_Percent: 3575 BinaryAmp: 3576 case OO_Caret: 3577 case OO_Pipe: 3578 case OO_LessLess: 3579 case OO_GreaterGreater: 3580 // C++ [over.built]p17: 3581 // 3582 // For every pair of promoted integral types L and R, there 3583 // exist candidate operator functions of the form 3584 // 3585 // LR operator%(L, R); 3586 // LR operator&(L, R); 3587 // LR operator^(L, R); 3588 // LR operator|(L, R); 3589 // L operator<<(L, R); 3590 // L operator>>(L, R); 3591 // 3592 // where LR is the result of the usual arithmetic conversions 3593 // between types L and R. 3594 for (unsigned Left = FirstPromotedIntegralType; 3595 Left < LastPromotedIntegralType; ++Left) { 3596 for (unsigned Right = FirstPromotedIntegralType; 3597 Right < LastPromotedIntegralType; ++Right) { 3598 QualType LandR[2] = { ArithmeticTypes[Left], ArithmeticTypes[Right] }; 3599 QualType Result = (Op == OO_LessLess || Op == OO_GreaterGreater) 3600 ? LandR[0] 3601 : Context.UsualArithmeticConversionsType(LandR[0], LandR[1]); 3602 AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 3603 } 3604 } 3605 break; 3606 3607 case OO_Equal: 3608 // C++ [over.built]p20: 3609 // 3610 // For every pair (T, VQ), where T is an enumeration or 3611 // pointer to member type and VQ is either volatile or 3612 // empty, there exist candidate operator functions of the form 3613 // 3614 // VQ T& operator=(VQ T&, T); 3615 for (BuiltinCandidateTypeSet::iterator 3616 Enum = CandidateTypes.enumeration_begin(), 3617 EnumEnd = CandidateTypes.enumeration_end(); 3618 Enum != EnumEnd; ++Enum) 3619 AddBuiltinAssignmentOperatorCandidates(*this, *Enum, Args, 2, 3620 CandidateSet); 3621 for (BuiltinCandidateTypeSet::iterator 3622 MemPtr = CandidateTypes.member_pointer_begin(), 3623 MemPtrEnd = CandidateTypes.member_pointer_end(); 3624 MemPtr != MemPtrEnd; ++MemPtr) 3625 AddBuiltinAssignmentOperatorCandidates(*this, *MemPtr, Args, 2, 3626 CandidateSet); 3627 // Fall through. 3628 3629 case OO_PlusEqual: 3630 case OO_MinusEqual: 3631 // C++ [over.built]p19: 3632 // 3633 // For every pair (T, VQ), where T is any type and VQ is either 3634 // volatile or empty, there exist candidate operator functions 3635 // of the form 3636 // 3637 // T*VQ& operator=(T*VQ&, T*); 3638 // 3639 // C++ [over.built]p21: 3640 // 3641 // For every pair (T, VQ), where T is a cv-qualified or 3642 // cv-unqualified object type and VQ is either volatile or 3643 // empty, there exist candidate operator functions of the form 3644 // 3645 // T*VQ& operator+=(T*VQ&, ptrdiff_t); 3646 // T*VQ& operator-=(T*VQ&, ptrdiff_t); 3647 for (BuiltinCandidateTypeSet::iterator Ptr = CandidateTypes.pointer_begin(); 3648 Ptr != CandidateTypes.pointer_end(); ++Ptr) { 3649 QualType ParamTypes[2]; 3650 ParamTypes[1] = (Op == OO_Equal)? *Ptr : Context.getPointerDiffType(); 3651 3652 // non-volatile version 3653 ParamTypes[0] = Context.getLValueReferenceType(*Ptr); 3654 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 3655 /*IsAssigmentOperator=*/Op == OO_Equal); 3656 3657 if (!Context.getCanonicalType(*Ptr).isVolatileQualified() && 3658 VisibleTypeConversionsQuals.hasVolatile()) { 3659 // volatile version 3660 ParamTypes[0] 3661 = Context.getLValueReferenceType(Context.getVolatileType(*Ptr)); 3662 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 3663 /*IsAssigmentOperator=*/Op == OO_Equal); 3664 } 3665 } 3666 // Fall through. 3667 3668 case OO_StarEqual: 3669 case OO_SlashEqual: 3670 // C++ [over.built]p18: 3671 // 3672 // For every triple (L, VQ, R), where L is an arithmetic type, 3673 // VQ is either volatile or empty, and R is a promoted 3674 // arithmetic type, there exist candidate operator functions of 3675 // the form 3676 // 3677 // VQ L& operator=(VQ L&, R); 3678 // VQ L& operator*=(VQ L&, R); 3679 // VQ L& operator/=(VQ L&, R); 3680 // VQ L& operator+=(VQ L&, R); 3681 // VQ L& operator-=(VQ L&, R); 3682 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) { 3683 for (unsigned Right = FirstPromotedArithmeticType; 3684 Right < LastPromotedArithmeticType; ++Right) { 3685 QualType ParamTypes[2]; 3686 ParamTypes[1] = ArithmeticTypes[Right]; 3687 3688 // Add this built-in operator as a candidate (VQ is empty). 3689 ParamTypes[0] = Context.getLValueReferenceType(ArithmeticTypes[Left]); 3690 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 3691 /*IsAssigmentOperator=*/Op == OO_Equal); 3692 3693 // Add this built-in operator as a candidate (VQ is 'volatile'). 3694 if (VisibleTypeConversionsQuals.hasVolatile()) { 3695 ParamTypes[0] = Context.getVolatileType(ArithmeticTypes[Left]); 3696 ParamTypes[0] = Context.getLValueReferenceType(ParamTypes[0]); 3697 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 3698 /*IsAssigmentOperator=*/Op == OO_Equal); 3699 } 3700 } 3701 } 3702 break; 3703 3704 case OO_PercentEqual: 3705 case OO_LessLessEqual: 3706 case OO_GreaterGreaterEqual: 3707 case OO_AmpEqual: 3708 case OO_CaretEqual: 3709 case OO_PipeEqual: 3710 // C++ [over.built]p22: 3711 // 3712 // For every triple (L, VQ, R), where L is an integral type, VQ 3713 // is either volatile or empty, and R is a promoted integral 3714 // type, there exist candidate operator functions of the form 3715 // 3716 // VQ L& operator%=(VQ L&, R); 3717 // VQ L& operator<<=(VQ L&, R); 3718 // VQ L& operator>>=(VQ L&, R); 3719 // VQ L& operator&=(VQ L&, R); 3720 // VQ L& operator^=(VQ L&, R); 3721 // VQ L& operator|=(VQ L&, R); 3722 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) { 3723 for (unsigned Right = FirstPromotedIntegralType; 3724 Right < LastPromotedIntegralType; ++Right) { 3725 QualType ParamTypes[2]; 3726 ParamTypes[1] = ArithmeticTypes[Right]; 3727 3728 // Add this built-in operator as a candidate (VQ is empty). 3729 ParamTypes[0] = Context.getLValueReferenceType(ArithmeticTypes[Left]); 3730 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 3731 if (VisibleTypeConversionsQuals.hasVolatile()) { 3732 // Add this built-in operator as a candidate (VQ is 'volatile'). 3733 ParamTypes[0] = ArithmeticTypes[Left]; 3734 ParamTypes[0] = Context.getVolatileType(ParamTypes[0]); 3735 ParamTypes[0] = Context.getLValueReferenceType(ParamTypes[0]); 3736 AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 3737 } 3738 } 3739 } 3740 break; 3741 3742 case OO_Exclaim: { 3743 // C++ [over.operator]p23: 3744 // 3745 // There also exist candidate operator functions of the form 3746 // 3747 // bool operator!(bool); 3748 // bool operator&&(bool, bool); [BELOW] 3749 // bool operator||(bool, bool); [BELOW] 3750 QualType ParamTy = Context.BoolTy; 3751 AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet, 3752 /*IsAssignmentOperator=*/false, 3753 /*NumContextualBoolArguments=*/1); 3754 break; 3755 } 3756 3757 case OO_AmpAmp: 3758 case OO_PipePipe: { 3759 // C++ [over.operator]p23: 3760 // 3761 // There also exist candidate operator functions of the form 3762 // 3763 // bool operator!(bool); [ABOVE] 3764 // bool operator&&(bool, bool); 3765 // bool operator||(bool, bool); 3766 QualType ParamTypes[2] = { Context.BoolTy, Context.BoolTy }; 3767 AddBuiltinCandidate(Context.BoolTy, ParamTypes, Args, 2, CandidateSet, 3768 /*IsAssignmentOperator=*/false, 3769 /*NumContextualBoolArguments=*/2); 3770 break; 3771 } 3772 3773 case OO_Subscript: 3774 // C++ [over.built]p13: 3775 // 3776 // For every cv-qualified or cv-unqualified object type T there 3777 // exist candidate operator functions of the form 3778 // 3779 // T* operator+(T*, ptrdiff_t); [ABOVE] 3780 // T& operator[](T*, ptrdiff_t); 3781 // T* operator-(T*, ptrdiff_t); [ABOVE] 3782 // T* operator+(ptrdiff_t, T*); [ABOVE] 3783 // T& operator[](ptrdiff_t, T*); 3784 for (BuiltinCandidateTypeSet::iterator Ptr = CandidateTypes.pointer_begin(); 3785 Ptr != CandidateTypes.pointer_end(); ++Ptr) { 3786 QualType ParamTypes[2] = { *Ptr, Context.getPointerDiffType() }; 3787 QualType PointeeType = (*Ptr)->getAs<PointerType>()->getPointeeType(); 3788 QualType ResultTy = Context.getLValueReferenceType(PointeeType); 3789 3790 // T& operator[](T*, ptrdiff_t) 3791 AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 3792 3793 // T& operator[](ptrdiff_t, T*); 3794 ParamTypes[0] = ParamTypes[1]; 3795 ParamTypes[1] = *Ptr; 3796 AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 3797 } 3798 break; 3799 3800 case OO_ArrowStar: 3801 // C++ [over.built]p11: 3802 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type, 3803 // C1 is the same type as C2 or is a derived class of C2, T is an object 3804 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs, 3805 // there exist candidate operator functions of the form 3806 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*); 3807 // where CV12 is the union of CV1 and CV2. 3808 { 3809 for (BuiltinCandidateTypeSet::iterator Ptr = 3810 CandidateTypes.pointer_begin(); 3811 Ptr != CandidateTypes.pointer_end(); ++Ptr) { 3812 QualType C1Ty = (*Ptr); 3813 QualType C1; 3814 QualifierCollector Q1; 3815 if (const PointerType *PointerTy = C1Ty->getAs<PointerType>()) { 3816 C1 = QualType(Q1.strip(PointerTy->getPointeeType()), 0); 3817 if (!isa<RecordType>(C1)) 3818 continue; 3819 // heuristic to reduce number of builtin candidates in the set. 3820 // Add volatile/restrict version only if there are conversions to a 3821 // volatile/restrict type. 3822 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile()) 3823 continue; 3824 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict()) 3825 continue; 3826 } 3827 for (BuiltinCandidateTypeSet::iterator 3828 MemPtr = CandidateTypes.member_pointer_begin(), 3829 MemPtrEnd = CandidateTypes.member_pointer_end(); 3830 MemPtr != MemPtrEnd; ++MemPtr) { 3831 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr); 3832 QualType C2 = QualType(mptr->getClass(), 0); 3833 C2 = C2.getUnqualifiedType(); 3834 if (C1 != C2 && !IsDerivedFrom(C1, C2)) 3835 break; 3836 QualType ParamTypes[2] = { *Ptr, *MemPtr }; 3837 // build CV12 T& 3838 QualType T = mptr->getPointeeType(); 3839 if (!VisibleTypeConversionsQuals.hasVolatile() && 3840 T.isVolatileQualified()) 3841 continue; 3842 if (!VisibleTypeConversionsQuals.hasRestrict() && 3843 T.isRestrictQualified()) 3844 continue; 3845 T = Q1.apply(T); 3846 QualType ResultTy = Context.getLValueReferenceType(T); 3847 AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 3848 } 3849 } 3850 } 3851 break; 3852 3853 case OO_Conditional: 3854 // Note that we don't consider the first argument, since it has been 3855 // contextually converted to bool long ago. The candidates below are 3856 // therefore added as binary. 3857 // 3858 // C++ [over.built]p24: 3859 // For every type T, where T is a pointer or pointer-to-member type, 3860 // there exist candidate operator functions of the form 3861 // 3862 // T operator?(bool, T, T); 3863 // 3864 for (BuiltinCandidateTypeSet::iterator Ptr = CandidateTypes.pointer_begin(), 3865 E = CandidateTypes.pointer_end(); Ptr != E; ++Ptr) { 3866 QualType ParamTypes[2] = { *Ptr, *Ptr }; 3867 AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 3868 } 3869 for (BuiltinCandidateTypeSet::iterator Ptr = 3870 CandidateTypes.member_pointer_begin(), 3871 E = CandidateTypes.member_pointer_end(); Ptr != E; ++Ptr) { 3872 QualType ParamTypes[2] = { *Ptr, *Ptr }; 3873 AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 3874 } 3875 goto Conditional; 3876 } 3877} 3878 3879/// \brief Add function candidates found via argument-dependent lookup 3880/// to the set of overloading candidates. 3881/// 3882/// This routine performs argument-dependent name lookup based on the 3883/// given function name (which may also be an operator name) and adds 3884/// all of the overload candidates found by ADL to the overload 3885/// candidate set (C++ [basic.lookup.argdep]). 3886void 3887Sema::AddArgumentDependentLookupCandidates(DeclarationName Name, 3888 Expr **Args, unsigned NumArgs, 3889 bool HasExplicitTemplateArgs, 3890 const TemplateArgument *ExplicitTemplateArgs, 3891 unsigned NumExplicitTemplateArgs, 3892 OverloadCandidateSet& CandidateSet, 3893 bool PartialOverloading) { 3894 FunctionSet Functions; 3895 3896 // FIXME: Should we be trafficking in canonical function decls throughout? 3897 3898 // Record all of the function candidates that we've already 3899 // added to the overload set, so that we don't add those same 3900 // candidates a second time. 3901 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 3902 CandEnd = CandidateSet.end(); 3903 Cand != CandEnd; ++Cand) 3904 if (Cand->Function) { 3905 Functions.insert(Cand->Function); 3906 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 3907 Functions.insert(FunTmpl); 3908 } 3909 3910 // FIXME: Pass in the explicit template arguments? 3911 ArgumentDependentLookup(Name, /*Operator*/false, Args, NumArgs, Functions); 3912 3913 // Erase all of the candidates we already knew about. 3914 // FIXME: This is suboptimal. Is there a better way? 3915 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 3916 CandEnd = CandidateSet.end(); 3917 Cand != CandEnd; ++Cand) 3918 if (Cand->Function) { 3919 Functions.erase(Cand->Function); 3920 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 3921 Functions.erase(FunTmpl); 3922 } 3923 3924 // For each of the ADL candidates we found, add it to the overload 3925 // set. 3926 for (FunctionSet::iterator Func = Functions.begin(), 3927 FuncEnd = Functions.end(); 3928 Func != FuncEnd; ++Func) { 3929 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*Func)) { 3930 if (HasExplicitTemplateArgs) 3931 continue; 3932 3933 AddOverloadCandidate(FD, Args, NumArgs, CandidateSet, 3934 false, false, PartialOverloading); 3935 } else 3936 AddTemplateOverloadCandidate(cast<FunctionTemplateDecl>(*Func), 3937 HasExplicitTemplateArgs, 3938 ExplicitTemplateArgs, 3939 NumExplicitTemplateArgs, 3940 Args, NumArgs, CandidateSet); 3941 } 3942} 3943 3944/// isBetterOverloadCandidate - Determines whether the first overload 3945/// candidate is a better candidate than the second (C++ 13.3.3p1). 3946bool 3947Sema::isBetterOverloadCandidate(const OverloadCandidate& Cand1, 3948 const OverloadCandidate& Cand2) { 3949 // Define viable functions to be better candidates than non-viable 3950 // functions. 3951 if (!Cand2.Viable) 3952 return Cand1.Viable; 3953 else if (!Cand1.Viable) 3954 return false; 3955 3956 // C++ [over.match.best]p1: 3957 // 3958 // -- if F is a static member function, ICS1(F) is defined such 3959 // that ICS1(F) is neither better nor worse than ICS1(G) for 3960 // any function G, and, symmetrically, ICS1(G) is neither 3961 // better nor worse than ICS1(F). 3962 unsigned StartArg = 0; 3963 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument) 3964 StartArg = 1; 3965 3966 // C++ [over.match.best]p1: 3967 // A viable function F1 is defined to be a better function than another 3968 // viable function F2 if for all arguments i, ICSi(F1) is not a worse 3969 // conversion sequence than ICSi(F2), and then... 3970 unsigned NumArgs = Cand1.Conversions.size(); 3971 assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch"); 3972 bool HasBetterConversion = false; 3973 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) { 3974 switch (CompareImplicitConversionSequences(Cand1.Conversions[ArgIdx], 3975 Cand2.Conversions[ArgIdx])) { 3976 case ImplicitConversionSequence::Better: 3977 // Cand1 has a better conversion sequence. 3978 HasBetterConversion = true; 3979 break; 3980 3981 case ImplicitConversionSequence::Worse: 3982 // Cand1 can't be better than Cand2. 3983 return false; 3984 3985 case ImplicitConversionSequence::Indistinguishable: 3986 // Do nothing. 3987 break; 3988 } 3989 } 3990 3991 // -- for some argument j, ICSj(F1) is a better conversion sequence than 3992 // ICSj(F2), or, if not that, 3993 if (HasBetterConversion) 3994 return true; 3995 3996 // - F1 is a non-template function and F2 is a function template 3997 // specialization, or, if not that, 3998 if (Cand1.Function && !Cand1.Function->getPrimaryTemplate() && 3999 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 4000 return true; 4001 4002 // -- F1 and F2 are function template specializations, and the function 4003 // template for F1 is more specialized than the template for F2 4004 // according to the partial ordering rules described in 14.5.5.2, or, 4005 // if not that, 4006 if (Cand1.Function && Cand1.Function->getPrimaryTemplate() && 4007 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 4008 if (FunctionTemplateDecl *BetterTemplate 4009 = getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(), 4010 Cand2.Function->getPrimaryTemplate(), 4011 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion 4012 : TPOC_Call)) 4013 return BetterTemplate == Cand1.Function->getPrimaryTemplate(); 4014 4015 // -- the context is an initialization by user-defined conversion 4016 // (see 8.5, 13.3.1.5) and the standard conversion sequence 4017 // from the return type of F1 to the destination type (i.e., 4018 // the type of the entity being initialized) is a better 4019 // conversion sequence than the standard conversion sequence 4020 // from the return type of F2 to the destination type. 4021 if (Cand1.Function && Cand2.Function && 4022 isa<CXXConversionDecl>(Cand1.Function) && 4023 isa<CXXConversionDecl>(Cand2.Function)) { 4024 switch (CompareStandardConversionSequences(Cand1.FinalConversion, 4025 Cand2.FinalConversion)) { 4026 case ImplicitConversionSequence::Better: 4027 // Cand1 has a better conversion sequence. 4028 return true; 4029 4030 case ImplicitConversionSequence::Worse: 4031 // Cand1 can't be better than Cand2. 4032 return false; 4033 4034 case ImplicitConversionSequence::Indistinguishable: 4035 // Do nothing 4036 break; 4037 } 4038 } 4039 4040 return false; 4041} 4042 4043/// \brief Computes the best viable function (C++ 13.3.3) 4044/// within an overload candidate set. 4045/// 4046/// \param CandidateSet the set of candidate functions. 4047/// 4048/// \param Loc the location of the function name (or operator symbol) for 4049/// which overload resolution occurs. 4050/// 4051/// \param Best f overload resolution was successful or found a deleted 4052/// function, Best points to the candidate function found. 4053/// 4054/// \returns The result of overload resolution. 4055Sema::OverloadingResult 4056Sema::BestViableFunction(OverloadCandidateSet& CandidateSet, 4057 SourceLocation Loc, 4058 OverloadCandidateSet::iterator& Best) { 4059 // Find the best viable function. 4060 Best = CandidateSet.end(); 4061 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 4062 Cand != CandidateSet.end(); ++Cand) { 4063 if (Cand->Viable) { 4064 if (Best == CandidateSet.end() || isBetterOverloadCandidate(*Cand, *Best)) 4065 Best = Cand; 4066 } 4067 } 4068 4069 // If we didn't find any viable functions, abort. 4070 if (Best == CandidateSet.end()) 4071 return OR_No_Viable_Function; 4072 4073 // Make sure that this function is better than every other viable 4074 // function. If not, we have an ambiguity. 4075 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 4076 Cand != CandidateSet.end(); ++Cand) { 4077 if (Cand->Viable && 4078 Cand != Best && 4079 !isBetterOverloadCandidate(*Best, *Cand)) { 4080 Best = CandidateSet.end(); 4081 return OR_Ambiguous; 4082 } 4083 } 4084 4085 // Best is the best viable function. 4086 if (Best->Function && 4087 (Best->Function->isDeleted() || 4088 Best->Function->getAttr<UnavailableAttr>())) 4089 return OR_Deleted; 4090 4091 // C++ [basic.def.odr]p2: 4092 // An overloaded function is used if it is selected by overload resolution 4093 // when referred to from a potentially-evaluated expression. [Note: this 4094 // covers calls to named functions (5.2.2), operator overloading 4095 // (clause 13), user-defined conversions (12.3.2), allocation function for 4096 // placement new (5.3.4), as well as non-default initialization (8.5). 4097 if (Best->Function) 4098 MarkDeclarationReferenced(Loc, Best->Function); 4099 return OR_Success; 4100} 4101 4102/// PrintOverloadCandidates - When overload resolution fails, prints 4103/// diagnostic messages containing the candidates in the candidate 4104/// set. If OnlyViable is true, only viable candidates will be printed. 4105void 4106Sema::PrintOverloadCandidates(OverloadCandidateSet& CandidateSet, 4107 bool OnlyViable, 4108 const char *Opc, 4109 SourceLocation OpLoc) { 4110 OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 4111 LastCand = CandidateSet.end(); 4112 bool Reported = false; 4113 for (; Cand != LastCand; ++Cand) { 4114 if (Cand->Viable || !OnlyViable) { 4115 if (Cand->Function) { 4116 if (Cand->Function->isDeleted() || 4117 Cand->Function->getAttr<UnavailableAttr>()) { 4118 // Deleted or "unavailable" function. 4119 Diag(Cand->Function->getLocation(), diag::err_ovl_candidate_deleted) 4120 << Cand->Function->isDeleted(); 4121 } else if (FunctionTemplateDecl *FunTmpl 4122 = Cand->Function->getPrimaryTemplate()) { 4123 // Function template specialization 4124 // FIXME: Give a better reason! 4125 Diag(Cand->Function->getLocation(), diag::err_ovl_template_candidate) 4126 << getTemplateArgumentBindingsText(FunTmpl->getTemplateParameters(), 4127 *Cand->Function->getTemplateSpecializationArgs()); 4128 } else { 4129 // Normal function 4130 bool errReported = false; 4131 if (!Cand->Viable && Cand->Conversions.size() > 0) { 4132 for (int i = Cand->Conversions.size()-1; i >= 0; i--) { 4133 const ImplicitConversionSequence &Conversion = 4134 Cand->Conversions[i]; 4135 if ((Conversion.ConversionKind != 4136 ImplicitConversionSequence::BadConversion) || 4137 Conversion.ConversionFunctionSet.size() == 0) 4138 continue; 4139 Diag(Cand->Function->getLocation(), 4140 diag::err_ovl_candidate_not_viable) << (i+1); 4141 errReported = true; 4142 for (int j = Conversion.ConversionFunctionSet.size()-1; 4143 j >= 0; j--) { 4144 FunctionDecl *Func = Conversion.ConversionFunctionSet[j]; 4145 Diag(Func->getLocation(), diag::err_ovl_candidate); 4146 } 4147 } 4148 } 4149 if (!errReported) 4150 Diag(Cand->Function->getLocation(), diag::err_ovl_candidate); 4151 } 4152 } else if (Cand->IsSurrogate) { 4153 // Desugar the type of the surrogate down to a function type, 4154 // retaining as many typedefs as possible while still showing 4155 // the function type (and, therefore, its parameter types). 4156 QualType FnType = Cand->Surrogate->getConversionType(); 4157 bool isLValueReference = false; 4158 bool isRValueReference = false; 4159 bool isPointer = false; 4160 if (const LValueReferenceType *FnTypeRef = 4161 FnType->getAs<LValueReferenceType>()) { 4162 FnType = FnTypeRef->getPointeeType(); 4163 isLValueReference = true; 4164 } else if (const RValueReferenceType *FnTypeRef = 4165 FnType->getAs<RValueReferenceType>()) { 4166 FnType = FnTypeRef->getPointeeType(); 4167 isRValueReference = true; 4168 } 4169 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) { 4170 FnType = FnTypePtr->getPointeeType(); 4171 isPointer = true; 4172 } 4173 // Desugar down to a function type. 4174 FnType = QualType(FnType->getAs<FunctionType>(), 0); 4175 // Reconstruct the pointer/reference as appropriate. 4176 if (isPointer) FnType = Context.getPointerType(FnType); 4177 if (isRValueReference) FnType = Context.getRValueReferenceType(FnType); 4178 if (isLValueReference) FnType = Context.getLValueReferenceType(FnType); 4179 4180 Diag(Cand->Surrogate->getLocation(), diag::err_ovl_surrogate_cand) 4181 << FnType; 4182 } else if (OnlyViable) { 4183 assert(Cand->Conversions.size() <= 2 && 4184 "builtin-binary-operator-not-binary"); 4185 std::string TypeStr("operator"); 4186 TypeStr += Opc; 4187 TypeStr += "("; 4188 TypeStr += Cand->BuiltinTypes.ParamTypes[0].getAsString(); 4189 if (Cand->Conversions.size() == 1) { 4190 TypeStr += ")"; 4191 Diag(OpLoc, diag::err_ovl_builtin_unary_candidate) << TypeStr; 4192 } 4193 else { 4194 TypeStr += ", "; 4195 TypeStr += Cand->BuiltinTypes.ParamTypes[1].getAsString(); 4196 TypeStr += ")"; 4197 Diag(OpLoc, diag::err_ovl_builtin_binary_candidate) << TypeStr; 4198 } 4199 } 4200 else if (!Cand->Viable && !Reported) { 4201 // Non-viability might be due to ambiguous user-defined conversions, 4202 // needed for built-in operators. Report them as well, but only once 4203 // as we have typically many built-in candidates. 4204 unsigned NoOperands = Cand->Conversions.size(); 4205 for (unsigned ArgIdx = 0; ArgIdx < NoOperands; ++ArgIdx) { 4206 const ImplicitConversionSequence &ICS = Cand->Conversions[ArgIdx]; 4207 if (ICS.ConversionKind != ImplicitConversionSequence::BadConversion || 4208 ICS.ConversionFunctionSet.empty()) 4209 continue; 4210 if (CXXConversionDecl *Func = dyn_cast<CXXConversionDecl>( 4211 Cand->Conversions[ArgIdx].ConversionFunctionSet[0])) { 4212 QualType FromTy = 4213 QualType( 4214 static_cast<Type*>(ICS.UserDefined.Before.FromTypePtr),0); 4215 Diag(OpLoc,diag::note_ambiguous_type_conversion) 4216 << FromTy << Func->getConversionType(); 4217 } 4218 for (unsigned j = 0; j < ICS.ConversionFunctionSet.size(); j++) { 4219 FunctionDecl *Func = 4220 Cand->Conversions[ArgIdx].ConversionFunctionSet[j]; 4221 Diag(Func->getLocation(),diag::err_ovl_candidate); 4222 } 4223 } 4224 Reported = true; 4225 } 4226 } 4227 } 4228} 4229 4230/// ResolveAddressOfOverloadedFunction - Try to resolve the address of 4231/// an overloaded function (C++ [over.over]), where @p From is an 4232/// expression with overloaded function type and @p ToType is the type 4233/// we're trying to resolve to. For example: 4234/// 4235/// @code 4236/// int f(double); 4237/// int f(int); 4238/// 4239/// int (*pfd)(double) = f; // selects f(double) 4240/// @endcode 4241/// 4242/// This routine returns the resulting FunctionDecl if it could be 4243/// resolved, and NULL otherwise. When @p Complain is true, this 4244/// routine will emit diagnostics if there is an error. 4245FunctionDecl * 4246Sema::ResolveAddressOfOverloadedFunction(Expr *From, QualType ToType, 4247 bool Complain) { 4248 QualType FunctionType = ToType; 4249 bool IsMember = false; 4250 if (const PointerType *ToTypePtr = ToType->getAs<PointerType>()) 4251 FunctionType = ToTypePtr->getPointeeType(); 4252 else if (const ReferenceType *ToTypeRef = ToType->getAs<ReferenceType>()) 4253 FunctionType = ToTypeRef->getPointeeType(); 4254 else if (const MemberPointerType *MemTypePtr = 4255 ToType->getAs<MemberPointerType>()) { 4256 FunctionType = MemTypePtr->getPointeeType(); 4257 IsMember = true; 4258 } 4259 4260 // We only look at pointers or references to functions. 4261 FunctionType = Context.getCanonicalType(FunctionType).getUnqualifiedType(); 4262 if (!FunctionType->isFunctionType()) 4263 return 0; 4264 4265 // Find the actual overloaded function declaration. 4266 OverloadedFunctionDecl *Ovl = 0; 4267 4268 // C++ [over.over]p1: 4269 // [...] [Note: any redundant set of parentheses surrounding the 4270 // overloaded function name is ignored (5.1). ] 4271 Expr *OvlExpr = From->IgnoreParens(); 4272 4273 // C++ [over.over]p1: 4274 // [...] The overloaded function name can be preceded by the & 4275 // operator. 4276 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(OvlExpr)) { 4277 if (UnOp->getOpcode() == UnaryOperator::AddrOf) 4278 OvlExpr = UnOp->getSubExpr()->IgnoreParens(); 4279 } 4280 4281 bool HasExplicitTemplateArgs = false; 4282 const TemplateArgument *ExplicitTemplateArgs = 0; 4283 unsigned NumExplicitTemplateArgs = 0; 4284 4285 // Try to dig out the overloaded function. 4286 FunctionTemplateDecl *FunctionTemplate = 0; 4287 if (DeclRefExpr *DR = dyn_cast<DeclRefExpr>(OvlExpr)) { 4288 Ovl = dyn_cast<OverloadedFunctionDecl>(DR->getDecl()); 4289 FunctionTemplate = dyn_cast<FunctionTemplateDecl>(DR->getDecl()); 4290 } else if (MemberExpr *ME = dyn_cast<MemberExpr>(OvlExpr)) { 4291 Ovl = dyn_cast<OverloadedFunctionDecl>(ME->getMemberDecl()); 4292 FunctionTemplate = dyn_cast<FunctionTemplateDecl>(ME->getMemberDecl()); 4293 // FIXME: Explicit template arguments 4294 } else if (TemplateIdRefExpr *TIRE = dyn_cast<TemplateIdRefExpr>(OvlExpr)) { 4295 TemplateName Name = TIRE->getTemplateName(); 4296 Ovl = Name.getAsOverloadedFunctionDecl(); 4297 FunctionTemplate = 4298 dyn_cast_or_null<FunctionTemplateDecl>(Name.getAsTemplateDecl()); 4299 4300 HasExplicitTemplateArgs = true; 4301 ExplicitTemplateArgs = TIRE->getTemplateArgs(); 4302 NumExplicitTemplateArgs = TIRE->getNumTemplateArgs(); 4303 } 4304 4305 // If there's no overloaded function declaration or function template, 4306 // we're done. 4307 if (!Ovl && !FunctionTemplate) 4308 return 0; 4309 4310 OverloadIterator Fun; 4311 if (Ovl) 4312 Fun = Ovl; 4313 else 4314 Fun = FunctionTemplate; 4315 4316 // Look through all of the overloaded functions, searching for one 4317 // whose type matches exactly. 4318 llvm::SmallPtrSet<FunctionDecl *, 4> Matches; 4319 bool FoundNonTemplateFunction = false; 4320 for (OverloadIterator FunEnd; Fun != FunEnd; ++Fun) { 4321 // C++ [over.over]p3: 4322 // Non-member functions and static member functions match 4323 // targets of type "pointer-to-function" or "reference-to-function." 4324 // Nonstatic member functions match targets of 4325 // type "pointer-to-member-function." 4326 // Note that according to DR 247, the containing class does not matter. 4327 4328 if (FunctionTemplateDecl *FunctionTemplate 4329 = dyn_cast<FunctionTemplateDecl>(*Fun)) { 4330 if (CXXMethodDecl *Method 4331 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) { 4332 // Skip non-static function templates when converting to pointer, and 4333 // static when converting to member pointer. 4334 if (Method->isStatic() == IsMember) 4335 continue; 4336 } else if (IsMember) 4337 continue; 4338 4339 // C++ [over.over]p2: 4340 // If the name is a function template, template argument deduction is 4341 // done (14.8.2.2), and if the argument deduction succeeds, the 4342 // resulting template argument list is used to generate a single 4343 // function template specialization, which is added to the set of 4344 // overloaded functions considered. 4345 // FIXME: We don't really want to build the specialization here, do we? 4346 FunctionDecl *Specialization = 0; 4347 TemplateDeductionInfo Info(Context); 4348 if (TemplateDeductionResult Result 4349 = DeduceTemplateArguments(FunctionTemplate, HasExplicitTemplateArgs, 4350 ExplicitTemplateArgs, 4351 NumExplicitTemplateArgs, 4352 FunctionType, Specialization, Info)) { 4353 // FIXME: make a note of the failed deduction for diagnostics. 4354 (void)Result; 4355 } else { 4356 // FIXME: If the match isn't exact, shouldn't we just drop this as 4357 // a candidate? Find a testcase before changing the code. 4358 assert(FunctionType 4359 == Context.getCanonicalType(Specialization->getType())); 4360 Matches.insert( 4361 cast<FunctionDecl>(Specialization->getCanonicalDecl())); 4362 } 4363 } 4364 4365 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*Fun)) { 4366 // Skip non-static functions when converting to pointer, and static 4367 // when converting to member pointer. 4368 if (Method->isStatic() == IsMember) 4369 continue; 4370 } else if (IsMember) 4371 continue; 4372 4373 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(*Fun)) { 4374 if (FunctionType == Context.getCanonicalType(FunDecl->getType())) { 4375 Matches.insert(cast<FunctionDecl>(Fun->getCanonicalDecl())); 4376 FoundNonTemplateFunction = true; 4377 } 4378 } 4379 } 4380 4381 // If there were 0 or 1 matches, we're done. 4382 if (Matches.empty()) 4383 return 0; 4384 else if (Matches.size() == 1) { 4385 FunctionDecl *Result = *Matches.begin(); 4386 MarkDeclarationReferenced(From->getLocStart(), Result); 4387 return Result; 4388 } 4389 4390 // C++ [over.over]p4: 4391 // If more than one function is selected, [...] 4392 typedef llvm::SmallPtrSet<FunctionDecl *, 4>::iterator MatchIter; 4393 if (!FoundNonTemplateFunction) { 4394 // [...] and any given function template specialization F1 is 4395 // eliminated if the set contains a second function template 4396 // specialization whose function template is more specialized 4397 // than the function template of F1 according to the partial 4398 // ordering rules of 14.5.5.2. 4399 4400 // The algorithm specified above is quadratic. We instead use a 4401 // two-pass algorithm (similar to the one used to identify the 4402 // best viable function in an overload set) that identifies the 4403 // best function template (if it exists). 4404 llvm::SmallVector<FunctionDecl *, 8> TemplateMatches(Matches.begin(), 4405 Matches.end()); 4406 FunctionDecl *Result = 4407 getMostSpecialized(TemplateMatches.data(), TemplateMatches.size(), 4408 TPOC_Other, From->getLocStart(), 4409 PDiag(), 4410 PDiag(diag::err_addr_ovl_ambiguous) 4411 << TemplateMatches[0]->getDeclName(), 4412 PDiag(diag::err_ovl_template_candidate)); 4413 MarkDeclarationReferenced(From->getLocStart(), Result); 4414 return Result; 4415 } 4416 4417 // [...] any function template specializations in the set are 4418 // eliminated if the set also contains a non-template function, [...] 4419 llvm::SmallVector<FunctionDecl *, 4> RemainingMatches; 4420 for (MatchIter M = Matches.begin(), MEnd = Matches.end(); M != MEnd; ++M) 4421 if ((*M)->getPrimaryTemplate() == 0) 4422 RemainingMatches.push_back(*M); 4423 4424 // [...] After such eliminations, if any, there shall remain exactly one 4425 // selected function. 4426 if (RemainingMatches.size() == 1) { 4427 FunctionDecl *Result = RemainingMatches.front(); 4428 MarkDeclarationReferenced(From->getLocStart(), Result); 4429 return Result; 4430 } 4431 4432 // FIXME: We should probably return the same thing that BestViableFunction 4433 // returns (even if we issue the diagnostics here). 4434 Diag(From->getLocStart(), diag::err_addr_ovl_ambiguous) 4435 << RemainingMatches[0]->getDeclName(); 4436 for (unsigned I = 0, N = RemainingMatches.size(); I != N; ++I) 4437 Diag(RemainingMatches[I]->getLocation(), diag::err_ovl_candidate); 4438 return 0; 4439} 4440 4441/// \brief Add a single candidate to the overload set. 4442static void AddOverloadedCallCandidate(Sema &S, 4443 AnyFunctionDecl Callee, 4444 bool &ArgumentDependentLookup, 4445 bool HasExplicitTemplateArgs, 4446 const TemplateArgument *ExplicitTemplateArgs, 4447 unsigned NumExplicitTemplateArgs, 4448 Expr **Args, unsigned NumArgs, 4449 OverloadCandidateSet &CandidateSet, 4450 bool PartialOverloading) { 4451 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) { 4452 assert(!HasExplicitTemplateArgs && "Explicit template arguments?"); 4453 S.AddOverloadCandidate(Func, Args, NumArgs, CandidateSet, false, false, 4454 PartialOverloading); 4455 4456 if (Func->getDeclContext()->isRecord() || 4457 Func->getDeclContext()->isFunctionOrMethod()) 4458 ArgumentDependentLookup = false; 4459 return; 4460 } 4461 4462 FunctionTemplateDecl *FuncTemplate = cast<FunctionTemplateDecl>(Callee); 4463 S.AddTemplateOverloadCandidate(FuncTemplate, HasExplicitTemplateArgs, 4464 ExplicitTemplateArgs, 4465 NumExplicitTemplateArgs, 4466 Args, NumArgs, CandidateSet); 4467 4468 if (FuncTemplate->getDeclContext()->isRecord()) 4469 ArgumentDependentLookup = false; 4470} 4471 4472/// \brief Add the overload candidates named by callee and/or found by argument 4473/// dependent lookup to the given overload set. 4474void Sema::AddOverloadedCallCandidates(NamedDecl *Callee, 4475 DeclarationName &UnqualifiedName, 4476 bool &ArgumentDependentLookup, 4477 bool HasExplicitTemplateArgs, 4478 const TemplateArgument *ExplicitTemplateArgs, 4479 unsigned NumExplicitTemplateArgs, 4480 Expr **Args, unsigned NumArgs, 4481 OverloadCandidateSet &CandidateSet, 4482 bool PartialOverloading) { 4483 // Add the functions denoted by Callee to the set of candidate 4484 // functions. While we're doing so, track whether argument-dependent 4485 // lookup still applies, per: 4486 // 4487 // C++0x [basic.lookup.argdep]p3: 4488 // Let X be the lookup set produced by unqualified lookup (3.4.1) 4489 // and let Y be the lookup set produced by argument dependent 4490 // lookup (defined as follows). If X contains 4491 // 4492 // -- a declaration of a class member, or 4493 // 4494 // -- a block-scope function declaration that is not a 4495 // using-declaration (FIXME: check for using declaration), or 4496 // 4497 // -- a declaration that is neither a function or a function 4498 // template 4499 // 4500 // then Y is empty. 4501 if (!Callee) { 4502 // Nothing to do. 4503 } else if (OverloadedFunctionDecl *Ovl 4504 = dyn_cast<OverloadedFunctionDecl>(Callee)) { 4505 for (OverloadedFunctionDecl::function_iterator Func = Ovl->function_begin(), 4506 FuncEnd = Ovl->function_end(); 4507 Func != FuncEnd; ++Func) 4508 AddOverloadedCallCandidate(*this, *Func, ArgumentDependentLookup, 4509 HasExplicitTemplateArgs, 4510 ExplicitTemplateArgs, NumExplicitTemplateArgs, 4511 Args, NumArgs, CandidateSet, 4512 PartialOverloading); 4513 } else if (isa<FunctionDecl>(Callee) || isa<FunctionTemplateDecl>(Callee)) 4514 AddOverloadedCallCandidate(*this, 4515 AnyFunctionDecl::getFromNamedDecl(Callee), 4516 ArgumentDependentLookup, 4517 HasExplicitTemplateArgs, 4518 ExplicitTemplateArgs, NumExplicitTemplateArgs, 4519 Args, NumArgs, CandidateSet, 4520 PartialOverloading); 4521 // FIXME: assert isa<FunctionDecl> || isa<FunctionTemplateDecl> rather than 4522 // checking dynamically. 4523 4524 if (Callee) 4525 UnqualifiedName = Callee->getDeclName(); 4526 4527 if (ArgumentDependentLookup) 4528 AddArgumentDependentLookupCandidates(UnqualifiedName, Args, NumArgs, 4529 HasExplicitTemplateArgs, 4530 ExplicitTemplateArgs, 4531 NumExplicitTemplateArgs, 4532 CandidateSet, 4533 PartialOverloading); 4534} 4535 4536/// ResolveOverloadedCallFn - Given the call expression that calls Fn 4537/// (which eventually refers to the declaration Func) and the call 4538/// arguments Args/NumArgs, attempt to resolve the function call down 4539/// to a specific function. If overload resolution succeeds, returns 4540/// the function declaration produced by overload 4541/// resolution. Otherwise, emits diagnostics, deletes all of the 4542/// arguments and Fn, and returns NULL. 4543FunctionDecl *Sema::ResolveOverloadedCallFn(Expr *Fn, NamedDecl *Callee, 4544 DeclarationName UnqualifiedName, 4545 bool HasExplicitTemplateArgs, 4546 const TemplateArgument *ExplicitTemplateArgs, 4547 unsigned NumExplicitTemplateArgs, 4548 SourceLocation LParenLoc, 4549 Expr **Args, unsigned NumArgs, 4550 SourceLocation *CommaLocs, 4551 SourceLocation RParenLoc, 4552 bool &ArgumentDependentLookup) { 4553 OverloadCandidateSet CandidateSet; 4554 4555 // Add the functions denoted by Callee to the set of candidate 4556 // functions. 4557 AddOverloadedCallCandidates(Callee, UnqualifiedName, ArgumentDependentLookup, 4558 HasExplicitTemplateArgs, ExplicitTemplateArgs, 4559 NumExplicitTemplateArgs, Args, NumArgs, 4560 CandidateSet); 4561 OverloadCandidateSet::iterator Best; 4562 switch (BestViableFunction(CandidateSet, Fn->getLocStart(), Best)) { 4563 case OR_Success: 4564 return Best->Function; 4565 4566 case OR_No_Viable_Function: 4567 Diag(Fn->getSourceRange().getBegin(), 4568 diag::err_ovl_no_viable_function_in_call) 4569 << UnqualifiedName << Fn->getSourceRange(); 4570 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 4571 break; 4572 4573 case OR_Ambiguous: 4574 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_ambiguous_call) 4575 << UnqualifiedName << Fn->getSourceRange(); 4576 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 4577 break; 4578 4579 case OR_Deleted: 4580 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_deleted_call) 4581 << Best->Function->isDeleted() 4582 << UnqualifiedName 4583 << Fn->getSourceRange(); 4584 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 4585 break; 4586 } 4587 4588 // Overload resolution failed. Destroy all of the subexpressions and 4589 // return NULL. 4590 Fn->Destroy(Context); 4591 for (unsigned Arg = 0; Arg < NumArgs; ++Arg) 4592 Args[Arg]->Destroy(Context); 4593 return 0; 4594} 4595 4596/// \brief Create a unary operation that may resolve to an overloaded 4597/// operator. 4598/// 4599/// \param OpLoc The location of the operator itself (e.g., '*'). 4600/// 4601/// \param OpcIn The UnaryOperator::Opcode that describes this 4602/// operator. 4603/// 4604/// \param Functions The set of non-member functions that will be 4605/// considered by overload resolution. The caller needs to build this 4606/// set based on the context using, e.g., 4607/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 4608/// set should not contain any member functions; those will be added 4609/// by CreateOverloadedUnaryOp(). 4610/// 4611/// \param input The input argument. 4612Sema::OwningExprResult Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, 4613 unsigned OpcIn, 4614 FunctionSet &Functions, 4615 ExprArg input) { 4616 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 4617 Expr *Input = (Expr *)input.get(); 4618 4619 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc); 4620 assert(Op != OO_None && "Invalid opcode for overloaded unary operator"); 4621 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 4622 4623 Expr *Args[2] = { Input, 0 }; 4624 unsigned NumArgs = 1; 4625 4626 // For post-increment and post-decrement, add the implicit '0' as 4627 // the second argument, so that we know this is a post-increment or 4628 // post-decrement. 4629 if (Opc == UnaryOperator::PostInc || Opc == UnaryOperator::PostDec) { 4630 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false); 4631 Args[1] = new (Context) IntegerLiteral(Zero, Context.IntTy, 4632 SourceLocation()); 4633 NumArgs = 2; 4634 } 4635 4636 if (Input->isTypeDependent()) { 4637 OverloadedFunctionDecl *Overloads 4638 = OverloadedFunctionDecl::Create(Context, CurContext, OpName); 4639 for (FunctionSet::iterator Func = Functions.begin(), 4640 FuncEnd = Functions.end(); 4641 Func != FuncEnd; ++Func) 4642 Overloads->addOverload(*Func); 4643 4644 DeclRefExpr *Fn = new (Context) DeclRefExpr(Overloads, Context.OverloadTy, 4645 OpLoc, false, false); 4646 4647 input.release(); 4648 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 4649 &Args[0], NumArgs, 4650 Context.DependentTy, 4651 OpLoc)); 4652 } 4653 4654 // Build an empty overload set. 4655 OverloadCandidateSet CandidateSet; 4656 4657 // Add the candidates from the given function set. 4658 AddFunctionCandidates(Functions, &Args[0], NumArgs, CandidateSet, false); 4659 4660 // Add operator candidates that are member functions. 4661 AddMemberOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 4662 4663 // Add builtin operator candidates. 4664 AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 4665 4666 // Perform overload resolution. 4667 OverloadCandidateSet::iterator Best; 4668 switch (BestViableFunction(CandidateSet, OpLoc, Best)) { 4669 case OR_Success: { 4670 // We found a built-in operator or an overloaded operator. 4671 FunctionDecl *FnDecl = Best->Function; 4672 4673 if (FnDecl) { 4674 // We matched an overloaded operator. Build a call to that 4675 // operator. 4676 4677 // Convert the arguments. 4678 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 4679 if (PerformObjectArgumentInitialization(Input, Method)) 4680 return ExprError(); 4681 } else { 4682 // Convert the arguments. 4683 if (PerformCopyInitialization(Input, 4684 FnDecl->getParamDecl(0)->getType(), 4685 "passing")) 4686 return ExprError(); 4687 } 4688 4689 // Determine the result type 4690 QualType ResultTy = FnDecl->getResultType().getNonReferenceType(); 4691 4692 // Build the actual expression node. 4693 Expr *FnExpr = new (Context) DeclRefExpr(FnDecl, FnDecl->getType(), 4694 SourceLocation()); 4695 UsualUnaryConversions(FnExpr); 4696 4697 input.release(); 4698 4699 ExprOwningPtr<CallExpr> TheCall(this, 4700 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr, 4701 &Input, 1, ResultTy, OpLoc)); 4702 4703 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall.get(), 4704 FnDecl)) 4705 return ExprError(); 4706 4707 return MaybeBindToTemporary(TheCall.release()); 4708 } else { 4709 // We matched a built-in operator. Convert the arguments, then 4710 // break out so that we will build the appropriate built-in 4711 // operator node. 4712 if (PerformImplicitConversion(Input, Best->BuiltinTypes.ParamTypes[0], 4713 Best->Conversions[0], "passing")) 4714 return ExprError(); 4715 4716 break; 4717 } 4718 } 4719 4720 case OR_No_Viable_Function: 4721 // No viable function; fall through to handling this as a 4722 // built-in operator, which will produce an error message for us. 4723 break; 4724 4725 case OR_Ambiguous: 4726 Diag(OpLoc, diag::err_ovl_ambiguous_oper) 4727 << UnaryOperator::getOpcodeStr(Opc) 4728 << Input->getSourceRange(); 4729 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true, 4730 UnaryOperator::getOpcodeStr(Opc), OpLoc); 4731 return ExprError(); 4732 4733 case OR_Deleted: 4734 Diag(OpLoc, diag::err_ovl_deleted_oper) 4735 << Best->Function->isDeleted() 4736 << UnaryOperator::getOpcodeStr(Opc) 4737 << Input->getSourceRange(); 4738 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 4739 return ExprError(); 4740 } 4741 4742 // Either we found no viable overloaded operator or we matched a 4743 // built-in operator. In either case, fall through to trying to 4744 // build a built-in operation. 4745 input.release(); 4746 return CreateBuiltinUnaryOp(OpLoc, Opc, Owned(Input)); 4747} 4748 4749/// \brief Create a binary operation that may resolve to an overloaded 4750/// operator. 4751/// 4752/// \param OpLoc The location of the operator itself (e.g., '+'). 4753/// 4754/// \param OpcIn The BinaryOperator::Opcode that describes this 4755/// operator. 4756/// 4757/// \param Functions The set of non-member functions that will be 4758/// considered by overload resolution. The caller needs to build this 4759/// set based on the context using, e.g., 4760/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 4761/// set should not contain any member functions; those will be added 4762/// by CreateOverloadedBinOp(). 4763/// 4764/// \param LHS Left-hand argument. 4765/// \param RHS Right-hand argument. 4766Sema::OwningExprResult 4767Sema::CreateOverloadedBinOp(SourceLocation OpLoc, 4768 unsigned OpcIn, 4769 FunctionSet &Functions, 4770 Expr *LHS, Expr *RHS) { 4771 Expr *Args[2] = { LHS, RHS }; 4772 LHS=RHS=0; //Please use only Args instead of LHS/RHS couple 4773 4774 BinaryOperator::Opcode Opc = static_cast<BinaryOperator::Opcode>(OpcIn); 4775 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc); 4776 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 4777 4778 // If either side is type-dependent, create an appropriate dependent 4779 // expression. 4780 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 4781 // .* cannot be overloaded. 4782 if (Opc == BinaryOperator::PtrMemD) 4783 return Owned(new (Context) BinaryOperator(Args[0], Args[1], Opc, 4784 Context.DependentTy, OpLoc)); 4785 4786 OverloadedFunctionDecl *Overloads 4787 = OverloadedFunctionDecl::Create(Context, CurContext, OpName); 4788 for (FunctionSet::iterator Func = Functions.begin(), 4789 FuncEnd = Functions.end(); 4790 Func != FuncEnd; ++Func) 4791 Overloads->addOverload(*Func); 4792 4793 DeclRefExpr *Fn = new (Context) DeclRefExpr(Overloads, Context.OverloadTy, 4794 OpLoc, false, false); 4795 4796 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 4797 Args, 2, 4798 Context.DependentTy, 4799 OpLoc)); 4800 } 4801 4802 // If this is the .* operator, which is not overloadable, just 4803 // create a built-in binary operator. 4804 if (Opc == BinaryOperator::PtrMemD) 4805 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 4806 4807 // If this is one of the assignment operators, we only perform 4808 // overload resolution if the left-hand side is a class or 4809 // enumeration type (C++ [expr.ass]p3). 4810 if (Opc >= BinaryOperator::Assign && Opc <= BinaryOperator::OrAssign && 4811 !Args[0]->getType()->isOverloadableType()) 4812 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 4813 4814 // Build an empty overload set. 4815 OverloadCandidateSet CandidateSet; 4816 4817 // Add the candidates from the given function set. 4818 AddFunctionCandidates(Functions, Args, 2, CandidateSet, false); 4819 4820 // Add operator candidates that are member functions. 4821 AddMemberOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 4822 4823 // Add builtin operator candidates. 4824 AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 4825 4826 // Perform overload resolution. 4827 OverloadCandidateSet::iterator Best; 4828 switch (BestViableFunction(CandidateSet, OpLoc, Best)) { 4829 case OR_Success: { 4830 // We found a built-in operator or an overloaded operator. 4831 FunctionDecl *FnDecl = Best->Function; 4832 4833 if (FnDecl) { 4834 // We matched an overloaded operator. Build a call to that 4835 // operator. 4836 4837 // Convert the arguments. 4838 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 4839 if (PerformObjectArgumentInitialization(Args[0], Method) || 4840 PerformCopyInitialization(Args[1], FnDecl->getParamDecl(0)->getType(), 4841 "passing")) 4842 return ExprError(); 4843 } else { 4844 // Convert the arguments. 4845 if (PerformCopyInitialization(Args[0], FnDecl->getParamDecl(0)->getType(), 4846 "passing") || 4847 PerformCopyInitialization(Args[1], FnDecl->getParamDecl(1)->getType(), 4848 "passing")) 4849 return ExprError(); 4850 } 4851 4852 // Determine the result type 4853 QualType ResultTy 4854 = FnDecl->getType()->getAs<FunctionType>()->getResultType(); 4855 ResultTy = ResultTy.getNonReferenceType(); 4856 4857 // Build the actual expression node. 4858 Expr *FnExpr = new (Context) DeclRefExpr(FnDecl, FnDecl->getType(), 4859 OpLoc); 4860 UsualUnaryConversions(FnExpr); 4861 4862 ExprOwningPtr<CXXOperatorCallExpr> 4863 TheCall(this, new (Context) CXXOperatorCallExpr(Context, Op, FnExpr, 4864 Args, 2, ResultTy, 4865 OpLoc)); 4866 4867 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall.get(), 4868 FnDecl)) 4869 return ExprError(); 4870 4871 return MaybeBindToTemporary(TheCall.release()); 4872 } else { 4873 // We matched a built-in operator. Convert the arguments, then 4874 // break out so that we will build the appropriate built-in 4875 // operator node. 4876 if (PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 4877 Best->Conversions[0], "passing") || 4878 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 4879 Best->Conversions[1], "passing")) 4880 return ExprError(); 4881 4882 break; 4883 } 4884 } 4885 4886 case OR_No_Viable_Function: { 4887 // C++ [over.match.oper]p9: 4888 // If the operator is the operator , [...] and there are no 4889 // viable functions, then the operator is assumed to be the 4890 // built-in operator and interpreted according to clause 5. 4891 if (Opc == BinaryOperator::Comma) 4892 break; 4893 4894 // For class as left operand for assignment or compound assigment operator 4895 // do not fall through to handling in built-in, but report that no overloaded 4896 // assignment operator found 4897 OwningExprResult Result = ExprError(); 4898 if (Args[0]->getType()->isRecordType() && 4899 Opc >= BinaryOperator::Assign && Opc <= BinaryOperator::OrAssign) { 4900 Diag(OpLoc, diag::err_ovl_no_viable_oper) 4901 << BinaryOperator::getOpcodeStr(Opc) 4902 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 4903 } else { 4904 // No viable function; try to create a built-in operation, which will 4905 // produce an error. Then, show the non-viable candidates. 4906 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 4907 } 4908 assert(Result.isInvalid() && 4909 "C++ binary operator overloading is missing candidates!"); 4910 if (Result.isInvalid()) 4911 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false, 4912 BinaryOperator::getOpcodeStr(Opc), OpLoc); 4913 return move(Result); 4914 } 4915 4916 case OR_Ambiguous: 4917 Diag(OpLoc, diag::err_ovl_ambiguous_oper) 4918 << BinaryOperator::getOpcodeStr(Opc) 4919 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 4920 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true, 4921 BinaryOperator::getOpcodeStr(Opc), OpLoc); 4922 return ExprError(); 4923 4924 case OR_Deleted: 4925 Diag(OpLoc, diag::err_ovl_deleted_oper) 4926 << Best->Function->isDeleted() 4927 << BinaryOperator::getOpcodeStr(Opc) 4928 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 4929 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 4930 return ExprError(); 4931 } 4932 4933 // We matched a built-in operator; build it. 4934 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 4935} 4936 4937/// BuildCallToMemberFunction - Build a call to a member 4938/// function. MemExpr is the expression that refers to the member 4939/// function (and includes the object parameter), Args/NumArgs are the 4940/// arguments to the function call (not including the object 4941/// parameter). The caller needs to validate that the member 4942/// expression refers to a member function or an overloaded member 4943/// function. 4944Sema::ExprResult 4945Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE, 4946 SourceLocation LParenLoc, Expr **Args, 4947 unsigned NumArgs, SourceLocation *CommaLocs, 4948 SourceLocation RParenLoc) { 4949 // Dig out the member expression. This holds both the object 4950 // argument and the member function we're referring to. 4951 MemberExpr *MemExpr = 0; 4952 if (ParenExpr *ParenE = dyn_cast<ParenExpr>(MemExprE)) 4953 MemExpr = dyn_cast<MemberExpr>(ParenE->getSubExpr()); 4954 else 4955 MemExpr = dyn_cast<MemberExpr>(MemExprE); 4956 assert(MemExpr && "Building member call without member expression"); 4957 4958 // Extract the object argument. 4959 Expr *ObjectArg = MemExpr->getBase(); 4960 4961 CXXMethodDecl *Method = 0; 4962 if (isa<OverloadedFunctionDecl>(MemExpr->getMemberDecl()) || 4963 isa<FunctionTemplateDecl>(MemExpr->getMemberDecl())) { 4964 // Add overload candidates 4965 OverloadCandidateSet CandidateSet; 4966 DeclarationName DeclName = MemExpr->getMemberDecl()->getDeclName(); 4967 4968 for (OverloadIterator Func(MemExpr->getMemberDecl()), FuncEnd; 4969 Func != FuncEnd; ++Func) { 4970 if ((Method = dyn_cast<CXXMethodDecl>(*Func))) 4971 AddMethodCandidate(Method, ObjectArg, Args, NumArgs, CandidateSet, 4972 /*SuppressUserConversions=*/false); 4973 else 4974 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(*Func), 4975 MemExpr->hasExplicitTemplateArgumentList(), 4976 MemExpr->getTemplateArgs(), 4977 MemExpr->getNumTemplateArgs(), 4978 ObjectArg, Args, NumArgs, 4979 CandidateSet, 4980 /*SuppressUsedConversions=*/false); 4981 } 4982 4983 OverloadCandidateSet::iterator Best; 4984 switch (BestViableFunction(CandidateSet, MemExpr->getLocStart(), Best)) { 4985 case OR_Success: 4986 Method = cast<CXXMethodDecl>(Best->Function); 4987 break; 4988 4989 case OR_No_Viable_Function: 4990 Diag(MemExpr->getSourceRange().getBegin(), 4991 diag::err_ovl_no_viable_member_function_in_call) 4992 << DeclName << MemExprE->getSourceRange(); 4993 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 4994 // FIXME: Leaking incoming expressions! 4995 return true; 4996 4997 case OR_Ambiguous: 4998 Diag(MemExpr->getSourceRange().getBegin(), 4999 diag::err_ovl_ambiguous_member_call) 5000 << DeclName << MemExprE->getSourceRange(); 5001 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 5002 // FIXME: Leaking incoming expressions! 5003 return true; 5004 5005 case OR_Deleted: 5006 Diag(MemExpr->getSourceRange().getBegin(), 5007 diag::err_ovl_deleted_member_call) 5008 << Best->Function->isDeleted() 5009 << DeclName << MemExprE->getSourceRange(); 5010 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 5011 // FIXME: Leaking incoming expressions! 5012 return true; 5013 } 5014 5015 FixOverloadedFunctionReference(MemExpr, Method); 5016 } else { 5017 Method = dyn_cast<CXXMethodDecl>(MemExpr->getMemberDecl()); 5018 } 5019 5020 assert(Method && "Member call to something that isn't a method?"); 5021 ExprOwningPtr<CXXMemberCallExpr> 5022 TheCall(this, new (Context) CXXMemberCallExpr(Context, MemExpr, Args, 5023 NumArgs, 5024 Method->getResultType().getNonReferenceType(), 5025 RParenLoc)); 5026 5027 // Check for a valid return type. 5028 if (CheckCallReturnType(Method->getResultType(), MemExpr->getMemberLoc(), 5029 TheCall.get(), Method)) 5030 return true; 5031 5032 // Convert the object argument (for a non-static member function call). 5033 if (!Method->isStatic() && 5034 PerformObjectArgumentInitialization(ObjectArg, Method)) 5035 return true; 5036 MemExpr->setBase(ObjectArg); 5037 5038 // Convert the rest of the arguments 5039 const FunctionProtoType *Proto = cast<FunctionProtoType>(Method->getType()); 5040 if (ConvertArgumentsForCall(&*TheCall, MemExpr, Method, Proto, Args, NumArgs, 5041 RParenLoc)) 5042 return true; 5043 5044 if (CheckFunctionCall(Method, TheCall.get())) 5045 return true; 5046 5047 return MaybeBindToTemporary(TheCall.release()).release(); 5048} 5049 5050/// BuildCallToObjectOfClassType - Build a call to an object of class 5051/// type (C++ [over.call.object]), which can end up invoking an 5052/// overloaded function call operator (@c operator()) or performing a 5053/// user-defined conversion on the object argument. 5054Sema::ExprResult 5055Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Object, 5056 SourceLocation LParenLoc, 5057 Expr **Args, unsigned NumArgs, 5058 SourceLocation *CommaLocs, 5059 SourceLocation RParenLoc) { 5060 assert(Object->getType()->isRecordType() && "Requires object type argument"); 5061 const RecordType *Record = Object->getType()->getAs<RecordType>(); 5062 5063 // C++ [over.call.object]p1: 5064 // If the primary-expression E in the function call syntax 5065 // evaluates to a class object of type "cv T", then the set of 5066 // candidate functions includes at least the function call 5067 // operators of T. The function call operators of T are obtained by 5068 // ordinary lookup of the name operator() in the context of 5069 // (E).operator(). 5070 OverloadCandidateSet CandidateSet; 5071 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call); 5072 DeclContext::lookup_const_iterator Oper, OperEnd; 5073 for (llvm::tie(Oper, OperEnd) = Record->getDecl()->lookup(OpName); 5074 Oper != OperEnd; ++Oper) 5075 AddMethodCandidate(cast<CXXMethodDecl>(*Oper), Object, Args, NumArgs, 5076 CandidateSet, /*SuppressUserConversions=*/false); 5077 5078 if (RequireCompleteType(LParenLoc, Object->getType(), 5079 PartialDiagnostic(diag::err_incomplete_object_call) 5080 << Object->getSourceRange())) 5081 return true; 5082 5083 // C++ [over.call.object]p2: 5084 // In addition, for each conversion function declared in T of the 5085 // form 5086 // 5087 // operator conversion-type-id () cv-qualifier; 5088 // 5089 // where cv-qualifier is the same cv-qualification as, or a 5090 // greater cv-qualification than, cv, and where conversion-type-id 5091 // denotes the type "pointer to function of (P1,...,Pn) returning 5092 // R", or the type "reference to pointer to function of 5093 // (P1,...,Pn) returning R", or the type "reference to function 5094 // of (P1,...,Pn) returning R", a surrogate call function [...] 5095 // is also considered as a candidate function. Similarly, 5096 // surrogate call functions are added to the set of candidate 5097 // functions for each conversion function declared in an 5098 // accessible base class provided the function is not hidden 5099 // within T by another intervening declaration. 5100 // FIXME: Look in base classes for more conversion operators! 5101 OverloadedFunctionDecl *Conversions 5102 = cast<CXXRecordDecl>(Record->getDecl())->getConversionFunctions(); 5103 for (OverloadedFunctionDecl::function_iterator 5104 Func = Conversions->function_begin(), 5105 FuncEnd = Conversions->function_end(); 5106 Func != FuncEnd; ++Func) { 5107 CXXConversionDecl *Conv; 5108 FunctionTemplateDecl *ConvTemplate; 5109 GetFunctionAndTemplate(*Func, Conv, ConvTemplate); 5110 5111 // Skip over templated conversion functions; they aren't 5112 // surrogates. 5113 if (ConvTemplate) 5114 continue; 5115 5116 // Strip the reference type (if any) and then the pointer type (if 5117 // any) to get down to what might be a function type. 5118 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 5119 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 5120 ConvType = ConvPtrType->getPointeeType(); 5121 5122 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>()) 5123 AddSurrogateCandidate(Conv, Proto, Object, Args, NumArgs, CandidateSet); 5124 } 5125 5126 // Perform overload resolution. 5127 OverloadCandidateSet::iterator Best; 5128 switch (BestViableFunction(CandidateSet, Object->getLocStart(), Best)) { 5129 case OR_Success: 5130 // Overload resolution succeeded; we'll build the appropriate call 5131 // below. 5132 break; 5133 5134 case OR_No_Viable_Function: 5135 Diag(Object->getSourceRange().getBegin(), 5136 diag::err_ovl_no_viable_object_call) 5137 << Object->getType() << Object->getSourceRange(); 5138 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 5139 break; 5140 5141 case OR_Ambiguous: 5142 Diag(Object->getSourceRange().getBegin(), 5143 diag::err_ovl_ambiguous_object_call) 5144 << Object->getType() << Object->getSourceRange(); 5145 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 5146 break; 5147 5148 case OR_Deleted: 5149 Diag(Object->getSourceRange().getBegin(), 5150 diag::err_ovl_deleted_object_call) 5151 << Best->Function->isDeleted() 5152 << Object->getType() << Object->getSourceRange(); 5153 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 5154 break; 5155 } 5156 5157 if (Best == CandidateSet.end()) { 5158 // We had an error; delete all of the subexpressions and return 5159 // the error. 5160 Object->Destroy(Context); 5161 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 5162 Args[ArgIdx]->Destroy(Context); 5163 return true; 5164 } 5165 5166 if (Best->Function == 0) { 5167 // Since there is no function declaration, this is one of the 5168 // surrogate candidates. Dig out the conversion function. 5169 CXXConversionDecl *Conv 5170 = cast<CXXConversionDecl>( 5171 Best->Conversions[0].UserDefined.ConversionFunction); 5172 5173 // We selected one of the surrogate functions that converts the 5174 // object parameter to a function pointer. Perform the conversion 5175 // on the object argument, then let ActOnCallExpr finish the job. 5176 5177 // Create an implicit member expr to refer to the conversion operator. 5178 // and then call it. 5179 CXXMemberCallExpr *CE = 5180 BuildCXXMemberCallExpr(Object, Conv); 5181 5182 return ActOnCallExpr(S, ExprArg(*this, CE), LParenLoc, 5183 MultiExprArg(*this, (ExprTy**)Args, NumArgs), 5184 CommaLocs, RParenLoc).release(); 5185 } 5186 5187 // We found an overloaded operator(). Build a CXXOperatorCallExpr 5188 // that calls this method, using Object for the implicit object 5189 // parameter and passing along the remaining arguments. 5190 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 5191 const FunctionProtoType *Proto = Method->getType()->getAs<FunctionProtoType>(); 5192 5193 unsigned NumArgsInProto = Proto->getNumArgs(); 5194 unsigned NumArgsToCheck = NumArgs; 5195 5196 // Build the full argument list for the method call (the 5197 // implicit object parameter is placed at the beginning of the 5198 // list). 5199 Expr **MethodArgs; 5200 if (NumArgs < NumArgsInProto) { 5201 NumArgsToCheck = NumArgsInProto; 5202 MethodArgs = new Expr*[NumArgsInProto + 1]; 5203 } else { 5204 MethodArgs = new Expr*[NumArgs + 1]; 5205 } 5206 MethodArgs[0] = Object; 5207 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 5208 MethodArgs[ArgIdx + 1] = Args[ArgIdx]; 5209 5210 Expr *NewFn = new (Context) DeclRefExpr(Method, Method->getType(), 5211 SourceLocation()); 5212 UsualUnaryConversions(NewFn); 5213 5214 // Once we've built TheCall, all of the expressions are properly 5215 // owned. 5216 QualType ResultTy = Method->getResultType().getNonReferenceType(); 5217 ExprOwningPtr<CXXOperatorCallExpr> 5218 TheCall(this, new (Context) CXXOperatorCallExpr(Context, OO_Call, NewFn, 5219 MethodArgs, NumArgs + 1, 5220 ResultTy, RParenLoc)); 5221 delete [] MethodArgs; 5222 5223 if (CheckCallReturnType(Method->getResultType(), LParenLoc, TheCall.get(), 5224 Method)) 5225 return true; 5226 5227 // We may have default arguments. If so, we need to allocate more 5228 // slots in the call for them. 5229 if (NumArgs < NumArgsInProto) 5230 TheCall->setNumArgs(Context, NumArgsInProto + 1); 5231 else if (NumArgs > NumArgsInProto) 5232 NumArgsToCheck = NumArgsInProto; 5233 5234 bool IsError = false; 5235 5236 // Initialize the implicit object parameter. 5237 IsError |= PerformObjectArgumentInitialization(Object, Method); 5238 TheCall->setArg(0, Object); 5239 5240 5241 // Check the argument types. 5242 for (unsigned i = 0; i != NumArgsToCheck; i++) { 5243 Expr *Arg; 5244 if (i < NumArgs) { 5245 Arg = Args[i]; 5246 5247 // Pass the argument. 5248 QualType ProtoArgType = Proto->getArgType(i); 5249 IsError |= PerformCopyInitialization(Arg, ProtoArgType, "passing"); 5250 } else { 5251 Arg = CXXDefaultArgExpr::Create(Context, Method->getParamDecl(i)); 5252 } 5253 5254 TheCall->setArg(i + 1, Arg); 5255 } 5256 5257 // If this is a variadic call, handle args passed through "...". 5258 if (Proto->isVariadic()) { 5259 // Promote the arguments (C99 6.5.2.2p7). 5260 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 5261 Expr *Arg = Args[i]; 5262 IsError |= DefaultVariadicArgumentPromotion(Arg, VariadicMethod); 5263 TheCall->setArg(i + 1, Arg); 5264 } 5265 } 5266 5267 if (IsError) return true; 5268 5269 if (CheckFunctionCall(Method, TheCall.get())) 5270 return true; 5271 5272 return MaybeBindToTemporary(TheCall.release()).release(); 5273} 5274 5275/// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator-> 5276/// (if one exists), where @c Base is an expression of class type and 5277/// @c Member is the name of the member we're trying to find. 5278Sema::OwningExprResult 5279Sema::BuildOverloadedArrowExpr(Scope *S, ExprArg BaseIn, SourceLocation OpLoc) { 5280 Expr *Base = static_cast<Expr *>(BaseIn.get()); 5281 assert(Base->getType()->isRecordType() && "left-hand side must have class type"); 5282 5283 // C++ [over.ref]p1: 5284 // 5285 // [...] An expression x->m is interpreted as (x.operator->())->m 5286 // for a class object x of type T if T::operator->() exists and if 5287 // the operator is selected as the best match function by the 5288 // overload resolution mechanism (13.3). 5289 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Arrow); 5290 OverloadCandidateSet CandidateSet; 5291 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>(); 5292 5293 LookupResult R; 5294 LookupQualifiedName(R, BaseRecord->getDecl(), OpName, LookupOrdinaryName); 5295 5296 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 5297 Oper != OperEnd; ++Oper) 5298 AddMethodCandidate(cast<CXXMethodDecl>(*Oper), Base, 0, 0, CandidateSet, 5299 /*SuppressUserConversions=*/false); 5300 5301 // Perform overload resolution. 5302 OverloadCandidateSet::iterator Best; 5303 switch (BestViableFunction(CandidateSet, OpLoc, Best)) { 5304 case OR_Success: 5305 // Overload resolution succeeded; we'll build the call below. 5306 break; 5307 5308 case OR_No_Viable_Function: 5309 if (CandidateSet.empty()) 5310 Diag(OpLoc, diag::err_typecheck_member_reference_arrow) 5311 << Base->getType() << Base->getSourceRange(); 5312 else 5313 Diag(OpLoc, diag::err_ovl_no_viable_oper) 5314 << "operator->" << Base->getSourceRange(); 5315 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 5316 return ExprError(); 5317 5318 case OR_Ambiguous: 5319 Diag(OpLoc, diag::err_ovl_ambiguous_oper) 5320 << "->" << Base->getSourceRange(); 5321 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 5322 return ExprError(); 5323 5324 case OR_Deleted: 5325 Diag(OpLoc, diag::err_ovl_deleted_oper) 5326 << Best->Function->isDeleted() 5327 << "->" << Base->getSourceRange(); 5328 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 5329 return ExprError(); 5330 } 5331 5332 // Convert the object parameter. 5333 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 5334 if (PerformObjectArgumentInitialization(Base, Method)) 5335 return ExprError(); 5336 5337 // No concerns about early exits now. 5338 BaseIn.release(); 5339 5340 // Build the operator call. 5341 Expr *FnExpr = new (Context) DeclRefExpr(Method, Method->getType(), 5342 SourceLocation()); 5343 UsualUnaryConversions(FnExpr); 5344 5345 QualType ResultTy = Method->getResultType().getNonReferenceType(); 5346 ExprOwningPtr<CXXOperatorCallExpr> 5347 TheCall(this, new (Context) CXXOperatorCallExpr(Context, OO_Arrow, FnExpr, 5348 &Base, 1, ResultTy, OpLoc)); 5349 5350 if (CheckCallReturnType(Method->getResultType(), OpLoc, TheCall.get(), 5351 Method)) 5352 return ExprError(); 5353 return move(TheCall); 5354} 5355 5356/// FixOverloadedFunctionReference - E is an expression that refers to 5357/// a C++ overloaded function (possibly with some parentheses and 5358/// perhaps a '&' around it). We have resolved the overloaded function 5359/// to the function declaration Fn, so patch up the expression E to 5360/// refer (possibly indirectly) to Fn. Returns the new expr. 5361Expr *Sema::FixOverloadedFunctionReference(Expr *E, FunctionDecl *Fn) { 5362 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 5363 Expr *NewExpr = FixOverloadedFunctionReference(PE->getSubExpr(), Fn); 5364 NewExpr->setType(PE->getSubExpr()->getType()); 5365 return NewExpr; 5366 } else if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) { 5367 assert(UnOp->getOpcode() == UnaryOperator::AddrOf && 5368 "Can only take the address of an overloaded function"); 5369 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 5370 if (Method->isStatic()) { 5371 // Do nothing: static member functions aren't any different 5372 // from non-member functions. 5373 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr())) { 5374 if (DRE->getQualifier()) { 5375 // We have taken the address of a pointer to member 5376 // function. Perform the computation here so that we get the 5377 // appropriate pointer to member type. 5378 DRE->setDecl(Fn); 5379 DRE->setType(Fn->getType()); 5380 QualType ClassType 5381 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 5382 E->setType(Context.getMemberPointerType(Fn->getType(), 5383 ClassType.getTypePtr())); 5384 return E; 5385 } 5386 } 5387 // FIXME: TemplateIdRefExpr referring to a member function template 5388 // specialization! 5389 } 5390 Expr *NewExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), Fn); 5391 UnOp->setSubExpr(NewExpr); 5392 UnOp->setType(Context.getPointerType(NewExpr->getType())); 5393 5394 return UnOp; 5395 } else if (DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E)) { 5396 assert((isa<OverloadedFunctionDecl>(DR->getDecl()) || 5397 isa<FunctionTemplateDecl>(DR->getDecl())) && 5398 "Expected overloaded function or function template"); 5399 DR->setDecl(Fn); 5400 E->setType(Fn->getType()); 5401 } else if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(E)) { 5402 MemExpr->setMemberDecl(Fn); 5403 E->setType(Fn->getType()); 5404 } else if (TemplateIdRefExpr *TID = dyn_cast<TemplateIdRefExpr>(E)) { 5405 E = DeclRefExpr::Create(Context, 5406 TID->getQualifier(), TID->getQualifierRange(), 5407 Fn, TID->getTemplateNameLoc(), 5408 true, 5409 TID->getLAngleLoc(), 5410 TID->getTemplateArgs(), 5411 TID->getNumTemplateArgs(), 5412 TID->getRAngleLoc(), 5413 Fn->getType(), 5414 /*FIXME?*/false, /*FIXME?*/false); 5415 5416 // FIXME: Don't destroy TID here, since we need its template arguments 5417 // to survive. 5418 // TID->Destroy(Context); 5419 } else { 5420 assert(false && "Invalid reference to overloaded function"); 5421 } 5422 5423 return E; 5424} 5425 5426} // end namespace clang 5427