1 //===--- SemaOverload.cpp - C++ Overloading -------------------------------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file provides Sema routines for C++ overloading.
11 //===----------------------------------------------------------------------===//
13 #include "clang/Sema/Overload.h"
14 #include "clang/AST/ASTContext.h"
15 #include "clang/AST/CXXInheritance.h"
16 #include "clang/AST/DeclObjC.h"
17 #include "clang/AST/Expr.h"
18 #include "clang/AST/ExprCXX.h"
19 #include "clang/AST/ExprObjC.h"
20 #include "clang/AST/TypeOrdering.h"
21 #include "clang/Basic/Diagnostic.h"
22 #include "clang/Basic/DiagnosticOptions.h"
23 #include "clang/Basic/PartialDiagnostic.h"
24 #include "clang/Basic/TargetInfo.h"
25 #include "clang/Sema/Initialization.h"
26 #include "clang/Sema/Lookup.h"
27 #include "clang/Sema/SemaInternal.h"
28 #include "clang/Sema/Template.h"
29 #include "clang/Sema/TemplateDeduction.h"
30 #include "llvm/ADT/DenseSet.h"
31 #include "llvm/ADT/Optional.h"
32 #include "llvm/ADT/STLExtras.h"
33 #include "llvm/ADT/SmallPtrSet.h"
34 #include "llvm/ADT/SmallString.h"
38 using namespace clang;
41 static bool functionHasPassObjectSizeParams(const FunctionDecl *FD) {
42 return llvm::any_of(FD->parameters(), [](const ParmVarDecl *P) {
43 return P->hasAttr<PassObjectSizeAttr>();
47 /// A convenience routine for creating a decayed reference to a function.
49 CreateFunctionRefExpr(Sema &S, FunctionDecl *Fn, NamedDecl *FoundDecl,
50 const Expr *Base, bool HadMultipleCandidates,
51 SourceLocation Loc = SourceLocation(),
52 const DeclarationNameLoc &LocInfo = DeclarationNameLoc()){
53 if (S.DiagnoseUseOfDecl(FoundDecl, Loc))
55 // If FoundDecl is different from Fn (such as if one is a template
56 // and the other a specialization), make sure DiagnoseUseOfDecl is
58 // FIXME: This would be more comprehensively addressed by modifying
59 // DiagnoseUseOfDecl to accept both the FoundDecl and the decl
61 if (FoundDecl != Fn && S.DiagnoseUseOfDecl(Fn, Loc))
63 if (auto *FPT = Fn->getType()->getAs<FunctionProtoType>())
64 S.ResolveExceptionSpec(Loc, FPT);
65 DeclRefExpr *DRE = new (S.Context)
66 DeclRefExpr(S.Context, Fn, false, Fn->getType(), VK_LValue, Loc, LocInfo);
67 if (HadMultipleCandidates)
68 DRE->setHadMultipleCandidates(true);
70 S.MarkDeclRefReferenced(DRE, Base);
71 return S.ImpCastExprToType(DRE, S.Context.getPointerType(DRE->getType()),
72 CK_FunctionToPointerDecay);
75 static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType,
76 bool InOverloadResolution,
77 StandardConversionSequence &SCS,
79 bool AllowObjCWritebackConversion);
81 static bool IsTransparentUnionStandardConversion(Sema &S, Expr* From,
83 bool InOverloadResolution,
84 StandardConversionSequence &SCS,
86 static OverloadingResult
87 IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
88 UserDefinedConversionSequence& User,
89 OverloadCandidateSet& Conversions,
91 bool AllowObjCConversionOnExplicit);
94 static ImplicitConversionSequence::CompareKind
95 CompareStandardConversionSequences(Sema &S, SourceLocation Loc,
96 const StandardConversionSequence& SCS1,
97 const StandardConversionSequence& SCS2);
99 static ImplicitConversionSequence::CompareKind
100 CompareQualificationConversions(Sema &S,
101 const StandardConversionSequence& SCS1,
102 const StandardConversionSequence& SCS2);
104 static ImplicitConversionSequence::CompareKind
105 CompareDerivedToBaseConversions(Sema &S, SourceLocation Loc,
106 const StandardConversionSequence& SCS1,
107 const StandardConversionSequence& SCS2);
109 /// GetConversionRank - Retrieve the implicit conversion rank
110 /// corresponding to the given implicit conversion kind.
111 ImplicitConversionRank clang::GetConversionRank(ImplicitConversionKind Kind) {
112 static const ImplicitConversionRank
113 Rank[(int)ICK_Num_Conversion_Kinds] = {
133 ICR_OCL_Scalar_Widening,
134 ICR_Complex_Real_Conversion,
137 ICR_Writeback_Conversion,
138 ICR_Exact_Match, // NOTE(gbiv): This may not be completely right --
139 // it was omitted by the patch that added
140 // ICK_Zero_Event_Conversion
142 ICR_C_Conversion_Extension
144 return Rank[(int)Kind];
147 /// GetImplicitConversionName - Return the name of this kind of
148 /// implicit conversion.
149 static const char* GetImplicitConversionName(ImplicitConversionKind Kind) {
150 static const char* const Name[(int)ICK_Num_Conversion_Kinds] = {
154 "Function-to-pointer",
155 "Function pointer conversion",
157 "Integral promotion",
158 "Floating point promotion",
160 "Integral conversion",
161 "Floating conversion",
162 "Complex conversion",
163 "Floating-integral conversion",
164 "Pointer conversion",
165 "Pointer-to-member conversion",
166 "Boolean conversion",
167 "Compatible-types conversion",
168 "Derived-to-base conversion",
171 "Complex-real conversion",
172 "Block Pointer conversion",
173 "Transparent Union Conversion",
174 "Writeback conversion",
175 "OpenCL Zero Event Conversion",
176 "C specific type conversion",
177 "Incompatible pointer conversion"
182 /// StandardConversionSequence - Set the standard conversion
183 /// sequence to the identity conversion.
184 void StandardConversionSequence::setAsIdentityConversion() {
185 First = ICK_Identity;
186 Second = ICK_Identity;
187 Third = ICK_Identity;
188 DeprecatedStringLiteralToCharPtr = false;
189 QualificationIncludesObjCLifetime = false;
190 ReferenceBinding = false;
191 DirectBinding = false;
192 IsLvalueReference = true;
193 BindsToFunctionLvalue = false;
194 BindsToRvalue = false;
195 BindsImplicitObjectArgumentWithoutRefQualifier = false;
196 ObjCLifetimeConversionBinding = false;
197 CopyConstructor = nullptr;
200 /// getRank - Retrieve the rank of this standard conversion sequence
201 /// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the
202 /// implicit conversions.
203 ImplicitConversionRank StandardConversionSequence::getRank() const {
204 ImplicitConversionRank Rank = ICR_Exact_Match;
205 if (GetConversionRank(First) > Rank)
206 Rank = GetConversionRank(First);
207 if (GetConversionRank(Second) > Rank)
208 Rank = GetConversionRank(Second);
209 if (GetConversionRank(Third) > Rank)
210 Rank = GetConversionRank(Third);
214 /// isPointerConversionToBool - Determines whether this conversion is
215 /// a conversion of a pointer or pointer-to-member to bool. This is
216 /// used as part of the ranking of standard conversion sequences
217 /// (C++ 13.3.3.2p4).
218 bool StandardConversionSequence::isPointerConversionToBool() const {
219 // Note that FromType has not necessarily been transformed by the
220 // array-to-pointer or function-to-pointer implicit conversions, so
221 // check for their presence as well as checking whether FromType is
223 if (getToType(1)->isBooleanType() &&
224 (getFromType()->isPointerType() ||
225 getFromType()->isMemberPointerType() ||
226 getFromType()->isObjCObjectPointerType() ||
227 getFromType()->isBlockPointerType() ||
228 getFromType()->isNullPtrType() ||
229 First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer))
235 /// isPointerConversionToVoidPointer - Determines whether this
236 /// conversion is a conversion of a pointer to a void pointer. This is
237 /// used as part of the ranking of standard conversion sequences (C++
240 StandardConversionSequence::
241 isPointerConversionToVoidPointer(ASTContext& Context) const {
242 QualType FromType = getFromType();
243 QualType ToType = getToType(1);
245 // Note that FromType has not necessarily been transformed by the
246 // array-to-pointer implicit conversion, so check for its presence
247 // and redo the conversion to get a pointer.
248 if (First == ICK_Array_To_Pointer)
249 FromType = Context.getArrayDecayedType(FromType);
251 if (Second == ICK_Pointer_Conversion && FromType->isAnyPointerType())
252 if (const PointerType* ToPtrType = ToType->getAs<PointerType>())
253 return ToPtrType->getPointeeType()->isVoidType();
258 /// Skip any implicit casts which could be either part of a narrowing conversion
259 /// or after one in an implicit conversion.
260 static const Expr *IgnoreNarrowingConversion(ASTContext &Ctx,
261 const Expr *Converted) {
262 // We can have cleanups wrapping the converted expression; these need to be
263 // preserved so that destructors run if necessary.
264 if (auto *EWC = dyn_cast<ExprWithCleanups>(Converted)) {
266 const_cast<Expr *>(IgnoreNarrowingConversion(Ctx, EWC->getSubExpr()));
267 return ExprWithCleanups::Create(Ctx, Inner, EWC->cleanupsHaveSideEffects(),
271 while (auto *ICE = dyn_cast<ImplicitCastExpr>(Converted)) {
272 switch (ICE->getCastKind()) {
274 case CK_IntegralCast:
275 case CK_IntegralToBoolean:
276 case CK_IntegralToFloating:
277 case CK_BooleanToSignedIntegral:
278 case CK_FloatingToIntegral:
279 case CK_FloatingToBoolean:
280 case CK_FloatingCast:
281 Converted = ICE->getSubExpr();
292 /// Check if this standard conversion sequence represents a narrowing
293 /// conversion, according to C++11 [dcl.init.list]p7.
295 /// \param Ctx The AST context.
296 /// \param Converted The result of applying this standard conversion sequence.
297 /// \param ConstantValue If this is an NK_Constant_Narrowing conversion, the
298 /// value of the expression prior to the narrowing conversion.
299 /// \param ConstantType If this is an NK_Constant_Narrowing conversion, the
300 /// type of the expression prior to the narrowing conversion.
301 /// \param IgnoreFloatToIntegralConversion If true type-narrowing conversions
302 /// from floating point types to integral types should be ignored.
303 NarrowingKind StandardConversionSequence::getNarrowingKind(
304 ASTContext &Ctx, const Expr *Converted, APValue &ConstantValue,
305 QualType &ConstantType, bool IgnoreFloatToIntegralConversion) const {
306 assert(Ctx.getLangOpts().CPlusPlus && "narrowing check outside C++");
308 // C++11 [dcl.init.list]p7:
309 // A narrowing conversion is an implicit conversion ...
310 QualType FromType = getToType(0);
311 QualType ToType = getToType(1);
313 // A conversion to an enumeration type is narrowing if the conversion to
314 // the underlying type is narrowing. This only arises for expressions of
315 // the form 'Enum{init}'.
316 if (auto *ET = ToType->getAs<EnumType>())
317 ToType = ET->getDecl()->getIntegerType();
320 // 'bool' is an integral type; dispatch to the right place to handle it.
321 case ICK_Boolean_Conversion:
322 if (FromType->isRealFloatingType())
323 goto FloatingIntegralConversion;
324 if (FromType->isIntegralOrUnscopedEnumerationType())
325 goto IntegralConversion;
326 // Boolean conversions can be from pointers and pointers to members
327 // [conv.bool], and those aren't considered narrowing conversions.
328 return NK_Not_Narrowing;
330 // -- from a floating-point type to an integer type, or
332 // -- from an integer type or unscoped enumeration type to a floating-point
333 // type, except where the source is a constant expression and the actual
334 // value after conversion will fit into the target type and will produce
335 // the original value when converted back to the original type, or
336 case ICK_Floating_Integral:
337 FloatingIntegralConversion:
338 if (FromType->isRealFloatingType() && ToType->isIntegralType(Ctx)) {
339 return NK_Type_Narrowing;
340 } else if (FromType->isIntegralOrUnscopedEnumerationType() &&
341 ToType->isRealFloatingType()) {
342 if (IgnoreFloatToIntegralConversion)
343 return NK_Not_Narrowing;
344 llvm::APSInt IntConstantValue;
345 const Expr *Initializer = IgnoreNarrowingConversion(Ctx, Converted);
346 assert(Initializer && "Unknown conversion expression");
348 // If it's value-dependent, we can't tell whether it's narrowing.
349 if (Initializer->isValueDependent())
350 return NK_Dependent_Narrowing;
352 if (Initializer->isIntegerConstantExpr(IntConstantValue, Ctx)) {
353 // Convert the integer to the floating type.
354 llvm::APFloat Result(Ctx.getFloatTypeSemantics(ToType));
355 Result.convertFromAPInt(IntConstantValue, IntConstantValue.isSigned(),
356 llvm::APFloat::rmNearestTiesToEven);
358 llvm::APSInt ConvertedValue = IntConstantValue;
360 Result.convertToInteger(ConvertedValue,
361 llvm::APFloat::rmTowardZero, &ignored);
362 // If the resulting value is different, this was a narrowing conversion.
363 if (IntConstantValue != ConvertedValue) {
364 ConstantValue = APValue(IntConstantValue);
365 ConstantType = Initializer->getType();
366 return NK_Constant_Narrowing;
369 // Variables are always narrowings.
370 return NK_Variable_Narrowing;
373 return NK_Not_Narrowing;
375 // -- from long double to double or float, or from double to float, except
376 // where the source is a constant expression and the actual value after
377 // conversion is within the range of values that can be represented (even
378 // if it cannot be represented exactly), or
379 case ICK_Floating_Conversion:
380 if (FromType->isRealFloatingType() && ToType->isRealFloatingType() &&
381 Ctx.getFloatingTypeOrder(FromType, ToType) == 1) {
382 // FromType is larger than ToType.
383 const Expr *Initializer = IgnoreNarrowingConversion(Ctx, Converted);
385 // If it's value-dependent, we can't tell whether it's narrowing.
386 if (Initializer->isValueDependent())
387 return NK_Dependent_Narrowing;
389 if (Initializer->isCXX11ConstantExpr(Ctx, &ConstantValue)) {
391 assert(ConstantValue.isFloat());
392 llvm::APFloat FloatVal = ConstantValue.getFloat();
393 // Convert the source value into the target type.
395 llvm::APFloat::opStatus ConvertStatus = FloatVal.convert(
396 Ctx.getFloatTypeSemantics(ToType),
397 llvm::APFloat::rmNearestTiesToEven, &ignored);
398 // If there was no overflow, the source value is within the range of
399 // values that can be represented.
400 if (ConvertStatus & llvm::APFloat::opOverflow) {
401 ConstantType = Initializer->getType();
402 return NK_Constant_Narrowing;
405 return NK_Variable_Narrowing;
408 return NK_Not_Narrowing;
410 // -- from an integer type or unscoped enumeration type to an integer type
411 // that cannot represent all the values of the original type, except where
412 // the source is a constant expression and the actual value after
413 // conversion will fit into the target type and will produce the original
414 // value when converted back to the original type.
415 case ICK_Integral_Conversion:
416 IntegralConversion: {
417 assert(FromType->isIntegralOrUnscopedEnumerationType());
418 assert(ToType->isIntegralOrUnscopedEnumerationType());
419 const bool FromSigned = FromType->isSignedIntegerOrEnumerationType();
420 const unsigned FromWidth = Ctx.getIntWidth(FromType);
421 const bool ToSigned = ToType->isSignedIntegerOrEnumerationType();
422 const unsigned ToWidth = Ctx.getIntWidth(ToType);
424 if (FromWidth > ToWidth ||
425 (FromWidth == ToWidth && FromSigned != ToSigned) ||
426 (FromSigned && !ToSigned)) {
427 // Not all values of FromType can be represented in ToType.
428 llvm::APSInt InitializerValue;
429 const Expr *Initializer = IgnoreNarrowingConversion(Ctx, Converted);
431 // If it's value-dependent, we can't tell whether it's narrowing.
432 if (Initializer->isValueDependent())
433 return NK_Dependent_Narrowing;
435 if (!Initializer->isIntegerConstantExpr(InitializerValue, Ctx)) {
436 // Such conversions on variables are always narrowing.
437 return NK_Variable_Narrowing;
439 bool Narrowing = false;
440 if (FromWidth < ToWidth) {
441 // Negative -> unsigned is narrowing. Otherwise, more bits is never
443 if (InitializerValue.isSigned() && InitializerValue.isNegative())
446 // Add a bit to the InitializerValue so we don't have to worry about
447 // signed vs. unsigned comparisons.
448 InitializerValue = InitializerValue.extend(
449 InitializerValue.getBitWidth() + 1);
450 // Convert the initializer to and from the target width and signed-ness.
451 llvm::APSInt ConvertedValue = InitializerValue;
452 ConvertedValue = ConvertedValue.trunc(ToWidth);
453 ConvertedValue.setIsSigned(ToSigned);
454 ConvertedValue = ConvertedValue.extend(InitializerValue.getBitWidth());
455 ConvertedValue.setIsSigned(InitializerValue.isSigned());
456 // If the result is different, this was a narrowing conversion.
457 if (ConvertedValue != InitializerValue)
461 ConstantType = Initializer->getType();
462 ConstantValue = APValue(InitializerValue);
463 return NK_Constant_Narrowing;
466 return NK_Not_Narrowing;
470 // Other kinds of conversions are not narrowings.
471 return NK_Not_Narrowing;
475 /// dump - Print this standard conversion sequence to standard
476 /// error. Useful for debugging overloading issues.
477 LLVM_DUMP_METHOD void StandardConversionSequence::dump() const {
478 raw_ostream &OS = llvm::errs();
479 bool PrintedSomething = false;
480 if (First != ICK_Identity) {
481 OS << GetImplicitConversionName(First);
482 PrintedSomething = true;
485 if (Second != ICK_Identity) {
486 if (PrintedSomething) {
489 OS << GetImplicitConversionName(Second);
491 if (CopyConstructor) {
492 OS << " (by copy constructor)";
493 } else if (DirectBinding) {
494 OS << " (direct reference binding)";
495 } else if (ReferenceBinding) {
496 OS << " (reference binding)";
498 PrintedSomething = true;
501 if (Third != ICK_Identity) {
502 if (PrintedSomething) {
505 OS << GetImplicitConversionName(Third);
506 PrintedSomething = true;
509 if (!PrintedSomething) {
510 OS << "No conversions required";
514 /// dump - Print this user-defined conversion sequence to standard
515 /// error. Useful for debugging overloading issues.
516 void UserDefinedConversionSequence::dump() const {
517 raw_ostream &OS = llvm::errs();
518 if (Before.First || Before.Second || Before.Third) {
522 if (ConversionFunction)
523 OS << '\'' << *ConversionFunction << '\'';
525 OS << "aggregate initialization";
526 if (After.First || After.Second || After.Third) {
532 /// dump - Print this implicit conversion sequence to standard
533 /// error. Useful for debugging overloading issues.
534 void ImplicitConversionSequence::dump() const {
535 raw_ostream &OS = llvm::errs();
536 if (isStdInitializerListElement())
537 OS << "Worst std::initializer_list element conversion: ";
538 switch (ConversionKind) {
539 case StandardConversion:
540 OS << "Standard conversion: ";
543 case UserDefinedConversion:
544 OS << "User-defined conversion: ";
547 case EllipsisConversion:
548 OS << "Ellipsis conversion";
550 case AmbiguousConversion:
551 OS << "Ambiguous conversion";
554 OS << "Bad conversion";
561 void AmbiguousConversionSequence::construct() {
562 new (&conversions()) ConversionSet();
565 void AmbiguousConversionSequence::destruct() {
566 conversions().~ConversionSet();
570 AmbiguousConversionSequence::copyFrom(const AmbiguousConversionSequence &O) {
571 FromTypePtr = O.FromTypePtr;
572 ToTypePtr = O.ToTypePtr;
573 new (&conversions()) ConversionSet(O.conversions());
577 // Structure used by DeductionFailureInfo to store
578 // template argument information.
579 struct DFIArguments {
580 TemplateArgument FirstArg;
581 TemplateArgument SecondArg;
583 // Structure used by DeductionFailureInfo to store
584 // template parameter and template argument information.
585 struct DFIParamWithArguments : DFIArguments {
586 TemplateParameter Param;
588 // Structure used by DeductionFailureInfo to store template argument
589 // information and the index of the problematic call argument.
590 struct DFIDeducedMismatchArgs : DFIArguments {
591 TemplateArgumentList *TemplateArgs;
592 unsigned CallArgIndex;
596 /// Convert from Sema's representation of template deduction information
597 /// to the form used in overload-candidate information.
599 clang::MakeDeductionFailureInfo(ASTContext &Context,
600 Sema::TemplateDeductionResult TDK,
601 TemplateDeductionInfo &Info) {
602 DeductionFailureInfo Result;
603 Result.Result = static_cast<unsigned>(TDK);
604 Result.HasDiagnostic = false;
606 case Sema::TDK_Invalid:
607 case Sema::TDK_InstantiationDepth:
608 case Sema::TDK_TooManyArguments:
609 case Sema::TDK_TooFewArguments:
610 case Sema::TDK_MiscellaneousDeductionFailure:
611 case Sema::TDK_CUDATargetMismatch:
612 Result.Data = nullptr;
615 case Sema::TDK_Incomplete:
616 case Sema::TDK_InvalidExplicitArguments:
617 Result.Data = Info.Param.getOpaqueValue();
620 case Sema::TDK_DeducedMismatch:
621 case Sema::TDK_DeducedMismatchNested: {
622 // FIXME: Should allocate from normal heap so that we can free this later.
623 auto *Saved = new (Context) DFIDeducedMismatchArgs;
624 Saved->FirstArg = Info.FirstArg;
625 Saved->SecondArg = Info.SecondArg;
626 Saved->TemplateArgs = Info.take();
627 Saved->CallArgIndex = Info.CallArgIndex;
632 case Sema::TDK_NonDeducedMismatch: {
633 // FIXME: Should allocate from normal heap so that we can free this later.
634 DFIArguments *Saved = new (Context) DFIArguments;
635 Saved->FirstArg = Info.FirstArg;
636 Saved->SecondArg = Info.SecondArg;
641 case Sema::TDK_IncompletePack:
642 // FIXME: It's slightly wasteful to allocate two TemplateArguments for this.
643 case Sema::TDK_Inconsistent:
644 case Sema::TDK_Underqualified: {
645 // FIXME: Should allocate from normal heap so that we can free this later.
646 DFIParamWithArguments *Saved = new (Context) DFIParamWithArguments;
647 Saved->Param = Info.Param;
648 Saved->FirstArg = Info.FirstArg;
649 Saved->SecondArg = Info.SecondArg;
654 case Sema::TDK_SubstitutionFailure:
655 Result.Data = Info.take();
656 if (Info.hasSFINAEDiagnostic()) {
657 PartialDiagnosticAt *Diag = new (Result.Diagnostic) PartialDiagnosticAt(
658 SourceLocation(), PartialDiagnostic::NullDiagnostic());
659 Info.takeSFINAEDiagnostic(*Diag);
660 Result.HasDiagnostic = true;
664 case Sema::TDK_Success:
665 case Sema::TDK_NonDependentConversionFailure:
666 llvm_unreachable("not a deduction failure");
672 void DeductionFailureInfo::Destroy() {
673 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
674 case Sema::TDK_Success:
675 case Sema::TDK_Invalid:
676 case Sema::TDK_InstantiationDepth:
677 case Sema::TDK_Incomplete:
678 case Sema::TDK_TooManyArguments:
679 case Sema::TDK_TooFewArguments:
680 case Sema::TDK_InvalidExplicitArguments:
681 case Sema::TDK_CUDATargetMismatch:
682 case Sema::TDK_NonDependentConversionFailure:
685 case Sema::TDK_IncompletePack:
686 case Sema::TDK_Inconsistent:
687 case Sema::TDK_Underqualified:
688 case Sema::TDK_DeducedMismatch:
689 case Sema::TDK_DeducedMismatchNested:
690 case Sema::TDK_NonDeducedMismatch:
691 // FIXME: Destroy the data?
695 case Sema::TDK_SubstitutionFailure:
696 // FIXME: Destroy the template argument list?
698 if (PartialDiagnosticAt *Diag = getSFINAEDiagnostic()) {
699 Diag->~PartialDiagnosticAt();
700 HasDiagnostic = false;
705 case Sema::TDK_MiscellaneousDeductionFailure:
710 PartialDiagnosticAt *DeductionFailureInfo::getSFINAEDiagnostic() {
712 return static_cast<PartialDiagnosticAt*>(static_cast<void*>(Diagnostic));
716 TemplateParameter DeductionFailureInfo::getTemplateParameter() {
717 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
718 case Sema::TDK_Success:
719 case Sema::TDK_Invalid:
720 case Sema::TDK_InstantiationDepth:
721 case Sema::TDK_TooManyArguments:
722 case Sema::TDK_TooFewArguments:
723 case Sema::TDK_SubstitutionFailure:
724 case Sema::TDK_DeducedMismatch:
725 case Sema::TDK_DeducedMismatchNested:
726 case Sema::TDK_NonDeducedMismatch:
727 case Sema::TDK_CUDATargetMismatch:
728 case Sema::TDK_NonDependentConversionFailure:
729 return TemplateParameter();
731 case Sema::TDK_Incomplete:
732 case Sema::TDK_InvalidExplicitArguments:
733 return TemplateParameter::getFromOpaqueValue(Data);
735 case Sema::TDK_IncompletePack:
736 case Sema::TDK_Inconsistent:
737 case Sema::TDK_Underqualified:
738 return static_cast<DFIParamWithArguments*>(Data)->Param;
741 case Sema::TDK_MiscellaneousDeductionFailure:
745 return TemplateParameter();
748 TemplateArgumentList *DeductionFailureInfo::getTemplateArgumentList() {
749 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
750 case Sema::TDK_Success:
751 case Sema::TDK_Invalid:
752 case Sema::TDK_InstantiationDepth:
753 case Sema::TDK_TooManyArguments:
754 case Sema::TDK_TooFewArguments:
755 case Sema::TDK_Incomplete:
756 case Sema::TDK_IncompletePack:
757 case Sema::TDK_InvalidExplicitArguments:
758 case Sema::TDK_Inconsistent:
759 case Sema::TDK_Underqualified:
760 case Sema::TDK_NonDeducedMismatch:
761 case Sema::TDK_CUDATargetMismatch:
762 case Sema::TDK_NonDependentConversionFailure:
765 case Sema::TDK_DeducedMismatch:
766 case Sema::TDK_DeducedMismatchNested:
767 return static_cast<DFIDeducedMismatchArgs*>(Data)->TemplateArgs;
769 case Sema::TDK_SubstitutionFailure:
770 return static_cast<TemplateArgumentList*>(Data);
773 case Sema::TDK_MiscellaneousDeductionFailure:
780 const TemplateArgument *DeductionFailureInfo::getFirstArg() {
781 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
782 case Sema::TDK_Success:
783 case Sema::TDK_Invalid:
784 case Sema::TDK_InstantiationDepth:
785 case Sema::TDK_Incomplete:
786 case Sema::TDK_TooManyArguments:
787 case Sema::TDK_TooFewArguments:
788 case Sema::TDK_InvalidExplicitArguments:
789 case Sema::TDK_SubstitutionFailure:
790 case Sema::TDK_CUDATargetMismatch:
791 case Sema::TDK_NonDependentConversionFailure:
794 case Sema::TDK_IncompletePack:
795 case Sema::TDK_Inconsistent:
796 case Sema::TDK_Underqualified:
797 case Sema::TDK_DeducedMismatch:
798 case Sema::TDK_DeducedMismatchNested:
799 case Sema::TDK_NonDeducedMismatch:
800 return &static_cast<DFIArguments*>(Data)->FirstArg;
803 case Sema::TDK_MiscellaneousDeductionFailure:
810 const TemplateArgument *DeductionFailureInfo::getSecondArg() {
811 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
812 case Sema::TDK_Success:
813 case Sema::TDK_Invalid:
814 case Sema::TDK_InstantiationDepth:
815 case Sema::TDK_Incomplete:
816 case Sema::TDK_IncompletePack:
817 case Sema::TDK_TooManyArguments:
818 case Sema::TDK_TooFewArguments:
819 case Sema::TDK_InvalidExplicitArguments:
820 case Sema::TDK_SubstitutionFailure:
821 case Sema::TDK_CUDATargetMismatch:
822 case Sema::TDK_NonDependentConversionFailure:
825 case Sema::TDK_Inconsistent:
826 case Sema::TDK_Underqualified:
827 case Sema::TDK_DeducedMismatch:
828 case Sema::TDK_DeducedMismatchNested:
829 case Sema::TDK_NonDeducedMismatch:
830 return &static_cast<DFIArguments*>(Data)->SecondArg;
833 case Sema::TDK_MiscellaneousDeductionFailure:
840 llvm::Optional<unsigned> DeductionFailureInfo::getCallArgIndex() {
841 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
842 case Sema::TDK_DeducedMismatch:
843 case Sema::TDK_DeducedMismatchNested:
844 return static_cast<DFIDeducedMismatchArgs*>(Data)->CallArgIndex;
851 bool OverloadCandidateSet::OperatorRewriteInfo::shouldAddReversed(
852 OverloadedOperatorKind Op) {
853 if (!AllowRewrittenCandidates)
855 return Op == OO_EqualEqual || Op == OO_Spaceship;
858 bool OverloadCandidateSet::OperatorRewriteInfo::shouldAddReversed(
859 ASTContext &Ctx, const FunctionDecl *FD) {
860 if (!shouldAddReversed(FD->getDeclName().getCXXOverloadedOperator()))
862 // Don't bother adding a reversed candidate that can never be a better
863 // match than the non-reversed version.
864 return FD->getNumParams() != 2 ||
865 !Ctx.hasSameUnqualifiedType(FD->getParamDecl(0)->getType(),
866 FD->getParamDecl(1)->getType()) ||
867 FD->hasAttr<EnableIfAttr>();
870 void OverloadCandidateSet::destroyCandidates() {
871 for (iterator i = begin(), e = end(); i != e; ++i) {
872 for (auto &C : i->Conversions)
873 C.~ImplicitConversionSequence();
874 if (!i->Viable && i->FailureKind == ovl_fail_bad_deduction)
875 i->DeductionFailure.Destroy();
879 void OverloadCandidateSet::clear(CandidateSetKind CSK) {
881 SlabAllocator.Reset();
882 NumInlineBytesUsed = 0;
889 class UnbridgedCastsSet {
894 SmallVector<Entry, 2> Entries;
897 void save(Sema &S, Expr *&E) {
898 assert(E->hasPlaceholderType(BuiltinType::ARCUnbridgedCast));
899 Entry entry = { &E, E };
900 Entries.push_back(entry);
901 E = S.stripARCUnbridgedCast(E);
905 for (SmallVectorImpl<Entry>::iterator
906 i = Entries.begin(), e = Entries.end(); i != e; ++i)
912 /// checkPlaceholderForOverload - Do any interesting placeholder-like
913 /// preprocessing on the given expression.
915 /// \param unbridgedCasts a collection to which to add unbridged casts;
916 /// without this, they will be immediately diagnosed as errors
918 /// Return true on unrecoverable error.
920 checkPlaceholderForOverload(Sema &S, Expr *&E,
921 UnbridgedCastsSet *unbridgedCasts = nullptr) {
922 if (const BuiltinType *placeholder = E->getType()->getAsPlaceholderType()) {
923 // We can't handle overloaded expressions here because overload
924 // resolution might reasonably tweak them.
925 if (placeholder->getKind() == BuiltinType::Overload) return false;
927 // If the context potentially accepts unbridged ARC casts, strip
928 // the unbridged cast and add it to the collection for later restoration.
929 if (placeholder->getKind() == BuiltinType::ARCUnbridgedCast &&
931 unbridgedCasts->save(S, E);
935 // Go ahead and check everything else.
936 ExprResult result = S.CheckPlaceholderExpr(E);
937 if (result.isInvalid())
948 /// checkArgPlaceholdersForOverload - Check a set of call operands for
950 static bool checkArgPlaceholdersForOverload(Sema &S,
952 UnbridgedCastsSet &unbridged) {
953 for (unsigned i = 0, e = Args.size(); i != e; ++i)
954 if (checkPlaceholderForOverload(S, Args[i], &unbridged))
960 /// Determine whether the given New declaration is an overload of the
961 /// declarations in Old. This routine returns Ovl_Match or Ovl_NonFunction if
962 /// New and Old cannot be overloaded, e.g., if New has the same signature as
963 /// some function in Old (C++ 1.3.10) or if the Old declarations aren't
964 /// functions (or function templates) at all. When it does return Ovl_Match or
965 /// Ovl_NonFunction, MatchedDecl will point to the decl that New cannot be
966 /// overloaded with. This decl may be a UsingShadowDecl on top of the underlying
969 /// Example: Given the following input:
971 /// void f(int, float); // #1
972 /// void f(int, int); // #2
973 /// int f(int, int); // #3
975 /// When we process #1, there is no previous declaration of "f", so IsOverload
976 /// will not be used.
978 /// When we process #2, Old contains only the FunctionDecl for #1. By comparing
979 /// the parameter types, we see that #1 and #2 are overloaded (since they have
980 /// different signatures), so this routine returns Ovl_Overload; MatchedDecl is
983 /// When we process #3, Old is an overload set containing #1 and #2. We compare
984 /// the signatures of #3 to #1 (they're overloaded, so we do nothing) and then
985 /// #3 to #2. Since the signatures of #3 and #2 are identical (return types of
986 /// functions are not part of the signature), IsOverload returns Ovl_Match and
987 /// MatchedDecl will be set to point to the FunctionDecl for #2.
989 /// 'NewIsUsingShadowDecl' indicates that 'New' is being introduced into a class
990 /// by a using declaration. The rules for whether to hide shadow declarations
991 /// ignore some properties which otherwise figure into a function template's
994 Sema::CheckOverload(Scope *S, FunctionDecl *New, const LookupResult &Old,
995 NamedDecl *&Match, bool NewIsUsingDecl) {
996 for (LookupResult::iterator I = Old.begin(), E = Old.end();
998 NamedDecl *OldD = *I;
1000 bool OldIsUsingDecl = false;
1001 if (isa<UsingShadowDecl>(OldD)) {
1002 OldIsUsingDecl = true;
1004 // We can always introduce two using declarations into the same
1005 // context, even if they have identical signatures.
1006 if (NewIsUsingDecl) continue;
1008 OldD = cast<UsingShadowDecl>(OldD)->getTargetDecl();
1011 // A using-declaration does not conflict with another declaration
1012 // if one of them is hidden.
1013 if ((OldIsUsingDecl || NewIsUsingDecl) && !isVisible(*I))
1016 // If either declaration was introduced by a using declaration,
1017 // we'll need to use slightly different rules for matching.
1018 // Essentially, these rules are the normal rules, except that
1019 // function templates hide function templates with different
1020 // return types or template parameter lists.
1021 bool UseMemberUsingDeclRules =
1022 (OldIsUsingDecl || NewIsUsingDecl) && CurContext->isRecord() &&
1023 !New->getFriendObjectKind();
1025 if (FunctionDecl *OldF = OldD->getAsFunction()) {
1026 if (!IsOverload(New, OldF, UseMemberUsingDeclRules)) {
1027 if (UseMemberUsingDeclRules && OldIsUsingDecl) {
1028 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I));
1032 if (!isa<FunctionTemplateDecl>(OldD) &&
1033 !shouldLinkPossiblyHiddenDecl(*I, New))
1040 // Builtins that have custom typechecking or have a reference should
1041 // not be overloadable or redeclarable.
1042 if (!getASTContext().canBuiltinBeRedeclared(OldF)) {
1044 return Ovl_NonFunction;
1046 } else if (isa<UsingDecl>(OldD) || isa<UsingPackDecl>(OldD)) {
1047 // We can overload with these, which can show up when doing
1048 // redeclaration checks for UsingDecls.
1049 assert(Old.getLookupKind() == LookupUsingDeclName);
1050 } else if (isa<TagDecl>(OldD)) {
1051 // We can always overload with tags by hiding them.
1052 } else if (auto *UUD = dyn_cast<UnresolvedUsingValueDecl>(OldD)) {
1053 // Optimistically assume that an unresolved using decl will
1054 // overload; if it doesn't, we'll have to diagnose during
1055 // template instantiation.
1057 // Exception: if the scope is dependent and this is not a class
1058 // member, the using declaration can only introduce an enumerator.
1059 if (UUD->getQualifier()->isDependent() && !UUD->isCXXClassMember()) {
1061 return Ovl_NonFunction;
1065 // Only function declarations can be overloaded; object and type
1066 // declarations cannot be overloaded.
1068 return Ovl_NonFunction;
1072 // C++ [temp.friend]p1:
1073 // For a friend function declaration that is not a template declaration:
1074 // -- if the name of the friend is a qualified or unqualified template-id,
1076 // -- if the name of the friend is a qualified-id and a matching
1077 // non-template function is found in the specified class or namespace,
1078 // the friend declaration refers to that function, otherwise,
1079 // -- if the name of the friend is a qualified-id and a matching function
1080 // template is found in the specified class or namespace, the friend
1081 // declaration refers to the deduced specialization of that function
1082 // template, otherwise
1083 // -- the name shall be an unqualified-id [...]
1084 // If we get here for a qualified friend declaration, we've just reached the
1085 // third bullet. If the type of the friend is dependent, skip this lookup
1086 // until instantiation.
1087 if (New->getFriendObjectKind() && New->getQualifier() &&
1088 !New->getDescribedFunctionTemplate() &&
1089 !New->getDependentSpecializationInfo() &&
1090 !New->getType()->isDependentType()) {
1091 LookupResult TemplateSpecResult(LookupResult::Temporary, Old);
1092 TemplateSpecResult.addAllDecls(Old);
1093 if (CheckFunctionTemplateSpecialization(New, nullptr, TemplateSpecResult,
1094 /*QualifiedFriend*/true)) {
1095 New->setInvalidDecl();
1096 return Ovl_Overload;
1099 Match = TemplateSpecResult.getAsSingle<FunctionDecl>();
1103 return Ovl_Overload;
1106 bool Sema::IsOverload(FunctionDecl *New, FunctionDecl *Old,
1107 bool UseMemberUsingDeclRules, bool ConsiderCudaAttrs) {
1108 // C++ [basic.start.main]p2: This function shall not be overloaded.
1112 // MSVCRT user defined entry points cannot be overloaded.
1113 if (New->isMSVCRTEntryPoint())
1116 FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate();
1117 FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate();
1119 // C++ [temp.fct]p2:
1120 // A function template can be overloaded with other function templates
1121 // and with normal (non-template) functions.
1122 if ((OldTemplate == nullptr) != (NewTemplate == nullptr))
1125 // Is the function New an overload of the function Old?
1126 QualType OldQType = Context.getCanonicalType(Old->getType());
1127 QualType NewQType = Context.getCanonicalType(New->getType());
1129 // Compare the signatures (C++ 1.3.10) of the two functions to
1130 // determine whether they are overloads. If we find any mismatch
1131 // in the signature, they are overloads.
1133 // If either of these functions is a K&R-style function (no
1134 // prototype), then we consider them to have matching signatures.
1135 if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) ||
1136 isa<FunctionNoProtoType>(NewQType.getTypePtr()))
1139 const FunctionProtoType *OldType = cast<FunctionProtoType>(OldQType);
1140 const FunctionProtoType *NewType = cast<FunctionProtoType>(NewQType);
1142 // The signature of a function includes the types of its
1143 // parameters (C++ 1.3.10), which includes the presence or absence
1144 // of the ellipsis; see C++ DR 357).
1145 if (OldQType != NewQType &&
1146 (OldType->getNumParams() != NewType->getNumParams() ||
1147 OldType->isVariadic() != NewType->isVariadic() ||
1148 !FunctionParamTypesAreEqual(OldType, NewType)))
1151 // C++ [temp.over.link]p4:
1152 // The signature of a function template consists of its function
1153 // signature, its return type and its template parameter list. The names
1154 // of the template parameters are significant only for establishing the
1155 // relationship between the template parameters and the rest of the
1158 // We check the return type and template parameter lists for function
1159 // templates first; the remaining checks follow.
1161 // However, we don't consider either of these when deciding whether
1162 // a member introduced by a shadow declaration is hidden.
1163 if (!UseMemberUsingDeclRules && NewTemplate &&
1164 (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
1165 OldTemplate->getTemplateParameters(),
1166 false, TPL_TemplateMatch) ||
1167 !Context.hasSameType(Old->getDeclaredReturnType(),
1168 New->getDeclaredReturnType())))
1171 // If the function is a class member, its signature includes the
1172 // cv-qualifiers (if any) and ref-qualifier (if any) on the function itself.
1174 // As part of this, also check whether one of the member functions
1175 // is static, in which case they are not overloads (C++
1176 // 13.1p2). While not part of the definition of the signature,
1177 // this check is important to determine whether these functions
1178 // can be overloaded.
1179 CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
1180 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
1181 if (OldMethod && NewMethod &&
1182 !OldMethod->isStatic() && !NewMethod->isStatic()) {
1183 if (OldMethod->getRefQualifier() != NewMethod->getRefQualifier()) {
1184 if (!UseMemberUsingDeclRules &&
1185 (OldMethod->getRefQualifier() == RQ_None ||
1186 NewMethod->getRefQualifier() == RQ_None)) {
1187 // C++0x [over.load]p2:
1188 // - Member function declarations with the same name and the same
1189 // parameter-type-list as well as member function template
1190 // declarations with the same name, the same parameter-type-list, and
1191 // the same template parameter lists cannot be overloaded if any of
1192 // them, but not all, have a ref-qualifier (8.3.5).
1193 Diag(NewMethod->getLocation(), diag::err_ref_qualifier_overload)
1194 << NewMethod->getRefQualifier() << OldMethod->getRefQualifier();
1195 Diag(OldMethod->getLocation(), diag::note_previous_declaration);
1200 // We may not have applied the implicit const for a constexpr member
1201 // function yet (because we haven't yet resolved whether this is a static
1202 // or non-static member function). Add it now, on the assumption that this
1203 // is a redeclaration of OldMethod.
1204 auto OldQuals = OldMethod->getMethodQualifiers();
1205 auto NewQuals = NewMethod->getMethodQualifiers();
1206 if (!getLangOpts().CPlusPlus14 && NewMethod->isConstexpr() &&
1207 !isa<CXXConstructorDecl>(NewMethod))
1208 NewQuals.addConst();
1209 // We do not allow overloading based off of '__restrict'.
1210 OldQuals.removeRestrict();
1211 NewQuals.removeRestrict();
1212 if (OldQuals != NewQuals)
1216 // Though pass_object_size is placed on parameters and takes an argument, we
1217 // consider it to be a function-level modifier for the sake of function
1218 // identity. Either the function has one or more parameters with
1219 // pass_object_size or it doesn't.
1220 if (functionHasPassObjectSizeParams(New) !=
1221 functionHasPassObjectSizeParams(Old))
1224 // enable_if attributes are an order-sensitive part of the signature.
1225 for (specific_attr_iterator<EnableIfAttr>
1226 NewI = New->specific_attr_begin<EnableIfAttr>(),
1227 NewE = New->specific_attr_end<EnableIfAttr>(),
1228 OldI = Old->specific_attr_begin<EnableIfAttr>(),
1229 OldE = Old->specific_attr_end<EnableIfAttr>();
1230 NewI != NewE || OldI != OldE; ++NewI, ++OldI) {
1231 if (NewI == NewE || OldI == OldE)
1233 llvm::FoldingSetNodeID NewID, OldID;
1234 NewI->getCond()->Profile(NewID, Context, true);
1235 OldI->getCond()->Profile(OldID, Context, true);
1240 if (getLangOpts().CUDA && ConsiderCudaAttrs) {
1241 // Don't allow overloading of destructors. (In theory we could, but it
1242 // would be a giant change to clang.)
1243 if (isa<CXXDestructorDecl>(New))
1246 CUDAFunctionTarget NewTarget = IdentifyCUDATarget(New),
1247 OldTarget = IdentifyCUDATarget(Old);
1248 if (NewTarget == CFT_InvalidTarget)
1251 assert((OldTarget != CFT_InvalidTarget) && "Unexpected invalid target.");
1253 // Allow overloading of functions with same signature and different CUDA
1254 // target attributes.
1255 return NewTarget != OldTarget;
1258 // The signatures match; this is not an overload.
1262 /// Tries a user-defined conversion from From to ToType.
1264 /// Produces an implicit conversion sequence for when a standard conversion
1265 /// is not an option. See TryImplicitConversion for more information.
1266 static ImplicitConversionSequence
1267 TryUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
1268 bool SuppressUserConversions,
1270 bool InOverloadResolution,
1272 bool AllowObjCWritebackConversion,
1273 bool AllowObjCConversionOnExplicit) {
1274 ImplicitConversionSequence ICS;
1276 if (SuppressUserConversions) {
1277 // We're not in the case above, so there is no conversion that
1279 ICS.setBad(BadConversionSequence::no_conversion, From, ToType);
1283 // Attempt user-defined conversion.
1284 OverloadCandidateSet Conversions(From->getExprLoc(),
1285 OverloadCandidateSet::CSK_Normal);
1286 switch (IsUserDefinedConversion(S, From, ToType, ICS.UserDefined,
1287 Conversions, AllowExplicit,
1288 AllowObjCConversionOnExplicit)) {
1291 ICS.setUserDefined();
1292 // C++ [over.ics.user]p4:
1293 // A conversion of an expression of class type to the same class
1294 // type is given Exact Match rank, and a conversion of an
1295 // expression of class type to a base class of that type is
1296 // given Conversion rank, in spite of the fact that a copy
1297 // constructor (i.e., a user-defined conversion function) is
1298 // called for those cases.
1299 if (CXXConstructorDecl *Constructor
1300 = dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) {
1302 = S.Context.getCanonicalType(From->getType().getUnqualifiedType());
1304 = S.Context.getCanonicalType(ToType).getUnqualifiedType();
1305 if (Constructor->isCopyConstructor() &&
1306 (FromCanon == ToCanon ||
1307 S.IsDerivedFrom(From->getBeginLoc(), FromCanon, ToCanon))) {
1308 // Turn this into a "standard" conversion sequence, so that it
1309 // gets ranked with standard conversion sequences.
1310 DeclAccessPair Found = ICS.UserDefined.FoundConversionFunction;
1312 ICS.Standard.setAsIdentityConversion();
1313 ICS.Standard.setFromType(From->getType());
1314 ICS.Standard.setAllToTypes(ToType);
1315 ICS.Standard.CopyConstructor = Constructor;
1316 ICS.Standard.FoundCopyConstructor = Found;
1317 if (ToCanon != FromCanon)
1318 ICS.Standard.Second = ICK_Derived_To_Base;
1325 ICS.Ambiguous.setFromType(From->getType());
1326 ICS.Ambiguous.setToType(ToType);
1327 for (OverloadCandidateSet::iterator Cand = Conversions.begin();
1328 Cand != Conversions.end(); ++Cand)
1330 ICS.Ambiguous.addConversion(Cand->FoundDecl, Cand->Function);
1334 case OR_No_Viable_Function:
1335 ICS.setBad(BadConversionSequence::no_conversion, From, ToType);
1342 /// TryImplicitConversion - Attempt to perform an implicit conversion
1343 /// from the given expression (Expr) to the given type (ToType). This
1344 /// function returns an implicit conversion sequence that can be used
1345 /// to perform the initialization. Given
1347 /// void f(float f);
1348 /// void g(int i) { f(i); }
1350 /// this routine would produce an implicit conversion sequence to
1351 /// describe the initialization of f from i, which will be a standard
1352 /// conversion sequence containing an lvalue-to-rvalue conversion (C++
1353 /// 4.1) followed by a floating-integral conversion (C++ 4.9).
1355 /// Note that this routine only determines how the conversion can be
1356 /// performed; it does not actually perform the conversion. As such,
1357 /// it will not produce any diagnostics if no conversion is available,
1358 /// but will instead return an implicit conversion sequence of kind
1359 /// "BadConversion".
1361 /// If @p SuppressUserConversions, then user-defined conversions are
1363 /// If @p AllowExplicit, then explicit user-defined conversions are
1366 /// \param AllowObjCWritebackConversion Whether we allow the Objective-C
1367 /// writeback conversion, which allows __autoreleasing id* parameters to
1368 /// be initialized with __strong id* or __weak id* arguments.
1369 static ImplicitConversionSequence
1370 TryImplicitConversion(Sema &S, Expr *From, QualType ToType,
1371 bool SuppressUserConversions,
1373 bool InOverloadResolution,
1375 bool AllowObjCWritebackConversion,
1376 bool AllowObjCConversionOnExplicit) {
1377 ImplicitConversionSequence ICS;
1378 if (IsStandardConversion(S, From, ToType, InOverloadResolution,
1379 ICS.Standard, CStyle, AllowObjCWritebackConversion)){
1384 if (!S.getLangOpts().CPlusPlus) {
1385 ICS.setBad(BadConversionSequence::no_conversion, From, ToType);
1389 // C++ [over.ics.user]p4:
1390 // A conversion of an expression of class type to the same class
1391 // type is given Exact Match rank, and a conversion of an
1392 // expression of class type to a base class of that type is
1393 // given Conversion rank, in spite of the fact that a copy/move
1394 // constructor (i.e., a user-defined conversion function) is
1395 // called for those cases.
1396 QualType FromType = From->getType();
1397 if (ToType->getAs<RecordType>() && FromType->getAs<RecordType>() &&
1398 (S.Context.hasSameUnqualifiedType(FromType, ToType) ||
1399 S.IsDerivedFrom(From->getBeginLoc(), FromType, ToType))) {
1401 ICS.Standard.setAsIdentityConversion();
1402 ICS.Standard.setFromType(FromType);
1403 ICS.Standard.setAllToTypes(ToType);
1405 // We don't actually check at this point whether there is a valid
1406 // copy/move constructor, since overloading just assumes that it
1407 // exists. When we actually perform initialization, we'll find the
1408 // appropriate constructor to copy the returned object, if needed.
1409 ICS.Standard.CopyConstructor = nullptr;
1411 // Determine whether this is considered a derived-to-base conversion.
1412 if (!S.Context.hasSameUnqualifiedType(FromType, ToType))
1413 ICS.Standard.Second = ICK_Derived_To_Base;
1418 return TryUserDefinedConversion(S, From, ToType, SuppressUserConversions,
1419 AllowExplicit, InOverloadResolution, CStyle,
1420 AllowObjCWritebackConversion,
1421 AllowObjCConversionOnExplicit);
1424 ImplicitConversionSequence
1425 Sema::TryImplicitConversion(Expr *From, QualType ToType,
1426 bool SuppressUserConversions,
1428 bool InOverloadResolution,
1430 bool AllowObjCWritebackConversion) {
1431 return ::TryImplicitConversion(*this, From, ToType,
1432 SuppressUserConversions, AllowExplicit,
1433 InOverloadResolution, CStyle,
1434 AllowObjCWritebackConversion,
1435 /*AllowObjCConversionOnExplicit=*/false);
1438 /// PerformImplicitConversion - Perform an implicit conversion of the
1439 /// expression From to the type ToType. Returns the
1440 /// converted expression. Flavor is the kind of conversion we're
1441 /// performing, used in the error message. If @p AllowExplicit,
1442 /// explicit user-defined conversions are permitted.
1444 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
1445 AssignmentAction Action, bool AllowExplicit) {
1446 ImplicitConversionSequence ICS;
1447 return PerformImplicitConversion(From, ToType, Action, AllowExplicit, ICS);
1451 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
1452 AssignmentAction Action, bool AllowExplicit,
1453 ImplicitConversionSequence& ICS) {
1454 if (checkPlaceholderForOverload(*this, From))
1457 // Objective-C ARC: Determine whether we will allow the writeback conversion.
1458 bool AllowObjCWritebackConversion
1459 = getLangOpts().ObjCAutoRefCount &&
1460 (Action == AA_Passing || Action == AA_Sending);
1461 if (getLangOpts().ObjC)
1462 CheckObjCBridgeRelatedConversions(From->getBeginLoc(), ToType,
1463 From->getType(), From);
1464 ICS = ::TryImplicitConversion(*this, From, ToType,
1465 /*SuppressUserConversions=*/false,
1467 /*InOverloadResolution=*/false,
1469 AllowObjCWritebackConversion,
1470 /*AllowObjCConversionOnExplicit=*/false);
1471 return PerformImplicitConversion(From, ToType, ICS, Action);
1474 /// Determine whether the conversion from FromType to ToType is a valid
1475 /// conversion that strips "noexcept" or "noreturn" off the nested function
1477 bool Sema::IsFunctionConversion(QualType FromType, QualType ToType,
1478 QualType &ResultTy) {
1479 if (Context.hasSameUnqualifiedType(FromType, ToType))
1482 // Permit the conversion F(t __attribute__((noreturn))) -> F(t)
1483 // or F(t noexcept) -> F(t)
1484 // where F adds one of the following at most once:
1486 // - a member pointer
1487 // - a block pointer
1488 // Changes here need matching changes in FindCompositePointerType.
1489 CanQualType CanTo = Context.getCanonicalType(ToType);
1490 CanQualType CanFrom = Context.getCanonicalType(FromType);
1491 Type::TypeClass TyClass = CanTo->getTypeClass();
1492 if (TyClass != CanFrom->getTypeClass()) return false;
1493 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) {
1494 if (TyClass == Type::Pointer) {
1495 CanTo = CanTo.castAs<PointerType>()->getPointeeType();
1496 CanFrom = CanFrom.castAs<PointerType>()->getPointeeType();
1497 } else if (TyClass == Type::BlockPointer) {
1498 CanTo = CanTo.castAs<BlockPointerType>()->getPointeeType();
1499 CanFrom = CanFrom.castAs<BlockPointerType>()->getPointeeType();
1500 } else if (TyClass == Type::MemberPointer) {
1501 auto ToMPT = CanTo.castAs<MemberPointerType>();
1502 auto FromMPT = CanFrom.castAs<MemberPointerType>();
1503 // A function pointer conversion cannot change the class of the function.
1504 if (ToMPT->getClass() != FromMPT->getClass())
1506 CanTo = ToMPT->getPointeeType();
1507 CanFrom = FromMPT->getPointeeType();
1512 TyClass = CanTo->getTypeClass();
1513 if (TyClass != CanFrom->getTypeClass()) return false;
1514 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto)
1518 const auto *FromFn = cast<FunctionType>(CanFrom);
1519 FunctionType::ExtInfo FromEInfo = FromFn->getExtInfo();
1521 const auto *ToFn = cast<FunctionType>(CanTo);
1522 FunctionType::ExtInfo ToEInfo = ToFn->getExtInfo();
1524 bool Changed = false;
1526 // Drop 'noreturn' if not present in target type.
1527 if (FromEInfo.getNoReturn() && !ToEInfo.getNoReturn()) {
1528 FromFn = Context.adjustFunctionType(FromFn, FromEInfo.withNoReturn(false));
1532 // Drop 'noexcept' if not present in target type.
1533 if (const auto *FromFPT = dyn_cast<FunctionProtoType>(FromFn)) {
1534 const auto *ToFPT = cast<FunctionProtoType>(ToFn);
1535 if (FromFPT->isNothrow() && !ToFPT->isNothrow()) {
1536 FromFn = cast<FunctionType>(
1537 Context.getFunctionTypeWithExceptionSpec(QualType(FromFPT, 0),
1543 // Convert FromFPT's ExtParameterInfo if necessary. The conversion is valid
1544 // only if the ExtParameterInfo lists of the two function prototypes can be
1545 // merged and the merged list is identical to ToFPT's ExtParameterInfo list.
1546 SmallVector<FunctionProtoType::ExtParameterInfo, 4> NewParamInfos;
1547 bool CanUseToFPT, CanUseFromFPT;
1548 if (Context.mergeExtParameterInfo(ToFPT, FromFPT, CanUseToFPT,
1549 CanUseFromFPT, NewParamInfos) &&
1550 CanUseToFPT && !CanUseFromFPT) {
1551 FunctionProtoType::ExtProtoInfo ExtInfo = FromFPT->getExtProtoInfo();
1552 ExtInfo.ExtParameterInfos =
1553 NewParamInfos.empty() ? nullptr : NewParamInfos.data();
1554 QualType QT = Context.getFunctionType(FromFPT->getReturnType(),
1555 FromFPT->getParamTypes(), ExtInfo);
1556 FromFn = QT->getAs<FunctionType>();
1564 assert(QualType(FromFn, 0).isCanonical());
1565 if (QualType(FromFn, 0) != CanTo) return false;
1571 /// Determine whether the conversion from FromType to ToType is a valid
1572 /// vector conversion.
1574 /// \param ICK Will be set to the vector conversion kind, if this is a vector
1576 static bool IsVectorConversion(Sema &S, QualType FromType,
1577 QualType ToType, ImplicitConversionKind &ICK) {
1578 // We need at least one of these types to be a vector type to have a vector
1580 if (!ToType->isVectorType() && !FromType->isVectorType())
1583 // Identical types require no conversions.
1584 if (S.Context.hasSameUnqualifiedType(FromType, ToType))
1587 // There are no conversions between extended vector types, only identity.
1588 if (ToType->isExtVectorType()) {
1589 // There are no conversions between extended vector types other than the
1590 // identity conversion.
1591 if (FromType->isExtVectorType())
1594 // Vector splat from any arithmetic type to a vector.
1595 if (FromType->isArithmeticType()) {
1596 ICK = ICK_Vector_Splat;
1601 // We can perform the conversion between vector types in the following cases:
1602 // 1)vector types are equivalent AltiVec and GCC vector types
1603 // 2)lax vector conversions are permitted and the vector types are of the
1605 if (ToType->isVectorType() && FromType->isVectorType()) {
1606 if (S.Context.areCompatibleVectorTypes(FromType, ToType) ||
1607 S.isLaxVectorConversion(FromType, ToType)) {
1608 ICK = ICK_Vector_Conversion;
1616 static bool tryAtomicConversion(Sema &S, Expr *From, QualType ToType,
1617 bool InOverloadResolution,
1618 StandardConversionSequence &SCS,
1621 /// IsStandardConversion - Determines whether there is a standard
1622 /// conversion sequence (C++ [conv], C++ [over.ics.scs]) from the
1623 /// expression From to the type ToType. Standard conversion sequences
1624 /// only consider non-class types; for conversions that involve class
1625 /// types, use TryImplicitConversion. If a conversion exists, SCS will
1626 /// contain the standard conversion sequence required to perform this
1627 /// conversion and this routine will return true. Otherwise, this
1628 /// routine will return false and the value of SCS is unspecified.
1629 static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType,
1630 bool InOverloadResolution,
1631 StandardConversionSequence &SCS,
1633 bool AllowObjCWritebackConversion) {
1634 QualType FromType = From->getType();
1636 // Standard conversions (C++ [conv])
1637 SCS.setAsIdentityConversion();
1638 SCS.IncompatibleObjC = false;
1639 SCS.setFromType(FromType);
1640 SCS.CopyConstructor = nullptr;
1642 // There are no standard conversions for class types in C++, so
1643 // abort early. When overloading in C, however, we do permit them.
1644 if (S.getLangOpts().CPlusPlus &&
1645 (FromType->isRecordType() || ToType->isRecordType()))
1648 // The first conversion can be an lvalue-to-rvalue conversion,
1649 // array-to-pointer conversion, or function-to-pointer conversion
1652 if (FromType == S.Context.OverloadTy) {
1653 DeclAccessPair AccessPair;
1654 if (FunctionDecl *Fn
1655 = S.ResolveAddressOfOverloadedFunction(From, ToType, false,
1657 // We were able to resolve the address of the overloaded function,
1658 // so we can convert to the type of that function.
1659 FromType = Fn->getType();
1660 SCS.setFromType(FromType);
1662 // we can sometimes resolve &foo<int> regardless of ToType, so check
1663 // if the type matches (identity) or we are converting to bool
1664 if (!S.Context.hasSameUnqualifiedType(
1665 S.ExtractUnqualifiedFunctionType(ToType), FromType)) {
1667 // if the function type matches except for [[noreturn]], it's ok
1668 if (!S.IsFunctionConversion(FromType,
1669 S.ExtractUnqualifiedFunctionType(ToType), resultTy))
1670 // otherwise, only a boolean conversion is standard
1671 if (!ToType->isBooleanType())
1675 // Check if the "from" expression is taking the address of an overloaded
1676 // function and recompute the FromType accordingly. Take advantage of the
1677 // fact that non-static member functions *must* have such an address-of
1679 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn);
1680 if (Method && !Method->isStatic()) {
1681 assert(isa<UnaryOperator>(From->IgnoreParens()) &&
1682 "Non-unary operator on non-static member address");
1683 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode()
1685 "Non-address-of operator on non-static member address");
1686 const Type *ClassType
1687 = S.Context.getTypeDeclType(Method->getParent()).getTypePtr();
1688 FromType = S.Context.getMemberPointerType(FromType, ClassType);
1689 } else if (isa<UnaryOperator>(From->IgnoreParens())) {
1690 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() ==
1692 "Non-address-of operator for overloaded function expression");
1693 FromType = S.Context.getPointerType(FromType);
1696 // Check that we've computed the proper type after overload resolution.
1697 // FIXME: FixOverloadedFunctionReference has side-effects; we shouldn't
1698 // be calling it from within an NDEBUG block.
1699 assert(S.Context.hasSameType(
1701 S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType()));
1706 // Lvalue-to-rvalue conversion (C++11 4.1):
1707 // A glvalue (3.10) of a non-function, non-array type T can
1708 // be converted to a prvalue.
1709 bool argIsLValue = From->isGLValue();
1711 !FromType->isFunctionType() && !FromType->isArrayType() &&
1712 S.Context.getCanonicalType(FromType) != S.Context.OverloadTy) {
1713 SCS.First = ICK_Lvalue_To_Rvalue;
1716 // ... if the lvalue has atomic type, the value has the non-atomic version
1717 // of the type of the lvalue ...
1718 if (const AtomicType *Atomic = FromType->getAs<AtomicType>())
1719 FromType = Atomic->getValueType();
1721 // If T is a non-class type, the type of the rvalue is the
1722 // cv-unqualified version of T. Otherwise, the type of the rvalue
1723 // is T (C++ 4.1p1). C++ can't get here with class types; in C, we
1724 // just strip the qualifiers because they don't matter.
1725 FromType = FromType.getUnqualifiedType();
1726 } else if (FromType->isArrayType()) {
1727 // Array-to-pointer conversion (C++ 4.2)
1728 SCS.First = ICK_Array_To_Pointer;
1730 // An lvalue or rvalue of type "array of N T" or "array of unknown
1731 // bound of T" can be converted to an rvalue of type "pointer to
1733 FromType = S.Context.getArrayDecayedType(FromType);
1735 if (S.IsStringLiteralToNonConstPointerConversion(From, ToType)) {
1736 // This conversion is deprecated in C++03 (D.4)
1737 SCS.DeprecatedStringLiteralToCharPtr = true;
1739 // For the purpose of ranking in overload resolution
1740 // (13.3.3.1.1), this conversion is considered an
1741 // array-to-pointer conversion followed by a qualification
1742 // conversion (4.4). (C++ 4.2p2)
1743 SCS.Second = ICK_Identity;
1744 SCS.Third = ICK_Qualification;
1745 SCS.QualificationIncludesObjCLifetime = false;
1746 SCS.setAllToTypes(FromType);
1749 } else if (FromType->isFunctionType() && argIsLValue) {
1750 // Function-to-pointer conversion (C++ 4.3).
1751 SCS.First = ICK_Function_To_Pointer;
1753 if (auto *DRE = dyn_cast<DeclRefExpr>(From->IgnoreParenCasts()))
1754 if (auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl()))
1755 if (!S.checkAddressOfFunctionIsAvailable(FD))
1758 // An lvalue of function type T can be converted to an rvalue of
1759 // type "pointer to T." The result is a pointer to the
1760 // function. (C++ 4.3p1).
1761 FromType = S.Context.getPointerType(FromType);
1763 // We don't require any conversions for the first step.
1764 SCS.First = ICK_Identity;
1766 SCS.setToType(0, FromType);
1768 // The second conversion can be an integral promotion, floating
1769 // point promotion, integral conversion, floating point conversion,
1770 // floating-integral conversion, pointer conversion,
1771 // pointer-to-member conversion, or boolean conversion (C++ 4p1).
1772 // For overloading in C, this can also be a "compatible-type"
1774 bool IncompatibleObjC = false;
1775 ImplicitConversionKind SecondICK = ICK_Identity;
1776 if (S.Context.hasSameUnqualifiedType(FromType, ToType)) {
1777 // The unqualified versions of the types are the same: there's no
1778 // conversion to do.
1779 SCS.Second = ICK_Identity;
1780 } else if (S.IsIntegralPromotion(From, FromType, ToType)) {
1781 // Integral promotion (C++ 4.5).
1782 SCS.Second = ICK_Integral_Promotion;
1783 FromType = ToType.getUnqualifiedType();
1784 } else if (S.IsFloatingPointPromotion(FromType, ToType)) {
1785 // Floating point promotion (C++ 4.6).
1786 SCS.Second = ICK_Floating_Promotion;
1787 FromType = ToType.getUnqualifiedType();
1788 } else if (S.IsComplexPromotion(FromType, ToType)) {
1789 // Complex promotion (Clang extension)
1790 SCS.Second = ICK_Complex_Promotion;
1791 FromType = ToType.getUnqualifiedType();
1792 } else if (ToType->isBooleanType() &&
1793 (FromType->isArithmeticType() ||
1794 FromType->isAnyPointerType() ||
1795 FromType->isBlockPointerType() ||
1796 FromType->isMemberPointerType() ||
1797 FromType->isNullPtrType())) {
1798 // Boolean conversions (C++ 4.12).
1799 SCS.Second = ICK_Boolean_Conversion;
1800 FromType = S.Context.BoolTy;
1801 } else if (FromType->isIntegralOrUnscopedEnumerationType() &&
1802 ToType->isIntegralType(S.Context)) {
1803 // Integral conversions (C++ 4.7).
1804 SCS.Second = ICK_Integral_Conversion;
1805 FromType = ToType.getUnqualifiedType();
1806 } else if (FromType->isAnyComplexType() && ToType->isAnyComplexType()) {
1807 // Complex conversions (C99 6.3.1.6)
1808 SCS.Second = ICK_Complex_Conversion;
1809 FromType = ToType.getUnqualifiedType();
1810 } else if ((FromType->isAnyComplexType() && ToType->isArithmeticType()) ||
1811 (ToType->isAnyComplexType() && FromType->isArithmeticType())) {
1812 // Complex-real conversions (C99 6.3.1.7)
1813 SCS.Second = ICK_Complex_Real;
1814 FromType = ToType.getUnqualifiedType();
1815 } else if (FromType->isRealFloatingType() && ToType->isRealFloatingType()) {
1816 // FIXME: disable conversions between long double and __float128 if
1817 // their representation is different until there is back end support
1818 // We of course allow this conversion if long double is really double.
1819 if (&S.Context.getFloatTypeSemantics(FromType) !=
1820 &S.Context.getFloatTypeSemantics(ToType)) {
1821 bool Float128AndLongDouble = ((FromType == S.Context.Float128Ty &&
1822 ToType == S.Context.LongDoubleTy) ||
1823 (FromType == S.Context.LongDoubleTy &&
1824 ToType == S.Context.Float128Ty));
1825 if (Float128AndLongDouble &&
1826 (&S.Context.getFloatTypeSemantics(S.Context.LongDoubleTy) ==
1827 &llvm::APFloat::PPCDoubleDouble()))
1830 // Floating point conversions (C++ 4.8).
1831 SCS.Second = ICK_Floating_Conversion;
1832 FromType = ToType.getUnqualifiedType();
1833 } else if ((FromType->isRealFloatingType() &&
1834 ToType->isIntegralType(S.Context)) ||
1835 (FromType->isIntegralOrUnscopedEnumerationType() &&
1836 ToType->isRealFloatingType())) {
1837 // Floating-integral conversions (C++ 4.9).
1838 SCS.Second = ICK_Floating_Integral;
1839 FromType = ToType.getUnqualifiedType();
1840 } else if (S.IsBlockPointerConversion(FromType, ToType, FromType)) {
1841 SCS.Second = ICK_Block_Pointer_Conversion;
1842 } else if (AllowObjCWritebackConversion &&
1843 S.isObjCWritebackConversion(FromType, ToType, FromType)) {
1844 SCS.Second = ICK_Writeback_Conversion;
1845 } else if (S.IsPointerConversion(From, FromType, ToType, InOverloadResolution,
1846 FromType, IncompatibleObjC)) {
1847 // Pointer conversions (C++ 4.10).
1848 SCS.Second = ICK_Pointer_Conversion;
1849 SCS.IncompatibleObjC = IncompatibleObjC;
1850 FromType = FromType.getUnqualifiedType();
1851 } else if (S.IsMemberPointerConversion(From, FromType, ToType,
1852 InOverloadResolution, FromType)) {
1853 // Pointer to member conversions (4.11).
1854 SCS.Second = ICK_Pointer_Member;
1855 } else if (IsVectorConversion(S, FromType, ToType, SecondICK)) {
1856 SCS.Second = SecondICK;
1857 FromType = ToType.getUnqualifiedType();
1858 } else if (!S.getLangOpts().CPlusPlus &&
1859 S.Context.typesAreCompatible(ToType, FromType)) {
1860 // Compatible conversions (Clang extension for C function overloading)
1861 SCS.Second = ICK_Compatible_Conversion;
1862 FromType = ToType.getUnqualifiedType();
1863 } else if (IsTransparentUnionStandardConversion(S, From, ToType,
1864 InOverloadResolution,
1866 SCS.Second = ICK_TransparentUnionConversion;
1868 } else if (tryAtomicConversion(S, From, ToType, InOverloadResolution, SCS,
1870 // tryAtomicConversion has updated the standard conversion sequence
1873 } else if (ToType->isEventT() &&
1874 From->isIntegerConstantExpr(S.getASTContext()) &&
1875 From->EvaluateKnownConstInt(S.getASTContext()) == 0) {
1876 SCS.Second = ICK_Zero_Event_Conversion;
1878 } else if (ToType->isQueueT() &&
1879 From->isIntegerConstantExpr(S.getASTContext()) &&
1880 (From->EvaluateKnownConstInt(S.getASTContext()) == 0)) {
1881 SCS.Second = ICK_Zero_Queue_Conversion;
1883 } else if (ToType->isSamplerT() &&
1884 From->isIntegerConstantExpr(S.getASTContext())) {
1885 SCS.Second = ICK_Compatible_Conversion;
1888 // No second conversion required.
1889 SCS.Second = ICK_Identity;
1891 SCS.setToType(1, FromType);
1893 // The third conversion can be a function pointer conversion or a
1894 // qualification conversion (C++ [conv.fctptr], [conv.qual]).
1895 bool ObjCLifetimeConversion;
1896 if (S.IsFunctionConversion(FromType, ToType, FromType)) {
1897 // Function pointer conversions (removing 'noexcept') including removal of
1898 // 'noreturn' (Clang extension).
1899 SCS.Third = ICK_Function_Conversion;
1900 } else if (S.IsQualificationConversion(FromType, ToType, CStyle,
1901 ObjCLifetimeConversion)) {
1902 SCS.Third = ICK_Qualification;
1903 SCS.QualificationIncludesObjCLifetime = ObjCLifetimeConversion;
1906 // No conversion required
1907 SCS.Third = ICK_Identity;
1910 // C++ [over.best.ics]p6:
1911 // [...] Any difference in top-level cv-qualification is
1912 // subsumed by the initialization itself and does not constitute
1913 // a conversion. [...]
1914 QualType CanonFrom = S.Context.getCanonicalType(FromType);
1915 QualType CanonTo = S.Context.getCanonicalType(ToType);
1916 if (CanonFrom.getLocalUnqualifiedType()
1917 == CanonTo.getLocalUnqualifiedType() &&
1918 CanonFrom.getLocalQualifiers() != CanonTo.getLocalQualifiers()) {
1920 CanonFrom = CanonTo;
1923 SCS.setToType(2, FromType);
1925 if (CanonFrom == CanonTo)
1928 // If we have not converted the argument type to the parameter type,
1929 // this is a bad conversion sequence, unless we're resolving an overload in C.
1930 if (S.getLangOpts().CPlusPlus || !InOverloadResolution)
1933 ExprResult ER = ExprResult{From};
1934 Sema::AssignConvertType Conv =
1935 S.CheckSingleAssignmentConstraints(ToType, ER,
1937 /*DiagnoseCFAudited=*/false,
1938 /*ConvertRHS=*/false);
1939 ImplicitConversionKind SecondConv;
1941 case Sema::Compatible:
1942 SecondConv = ICK_C_Only_Conversion;
1944 // For our purposes, discarding qualifiers is just as bad as using an
1945 // incompatible pointer. Note that an IncompatiblePointer conversion can drop
1946 // qualifiers, as well.
1947 case Sema::CompatiblePointerDiscardsQualifiers:
1948 case Sema::IncompatiblePointer:
1949 case Sema::IncompatiblePointerSign:
1950 SecondConv = ICK_Incompatible_Pointer_Conversion;
1956 // First can only be an lvalue conversion, so we pretend that this was the
1957 // second conversion. First should already be valid from earlier in the
1959 SCS.Second = SecondConv;
1960 SCS.setToType(1, ToType);
1962 // Third is Identity, because Second should rank us worse than any other
1963 // conversion. This could also be ICK_Qualification, but it's simpler to just
1964 // lump everything in with the second conversion, and we don't gain anything
1965 // from making this ICK_Qualification.
1966 SCS.Third = ICK_Identity;
1967 SCS.setToType(2, ToType);
1972 IsTransparentUnionStandardConversion(Sema &S, Expr* From,
1974 bool InOverloadResolution,
1975 StandardConversionSequence &SCS,
1978 const RecordType *UT = ToType->getAsUnionType();
1979 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
1981 // The field to initialize within the transparent union.
1982 RecordDecl *UD = UT->getDecl();
1983 // It's compatible if the expression matches any of the fields.
1984 for (const auto *it : UD->fields()) {
1985 if (IsStandardConversion(S, From, it->getType(), InOverloadResolution, SCS,
1986 CStyle, /*AllowObjCWritebackConversion=*/false)) {
1987 ToType = it->getType();
1994 /// IsIntegralPromotion - Determines whether the conversion from the
1995 /// expression From (whose potentially-adjusted type is FromType) to
1996 /// ToType is an integral promotion (C++ 4.5). If so, returns true and
1997 /// sets PromotedType to the promoted type.
1998 bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) {
1999 const BuiltinType *To = ToType->getAs<BuiltinType>();
2000 // All integers are built-in.
2005 // An rvalue of type char, signed char, unsigned char, short int, or
2006 // unsigned short int can be converted to an rvalue of type int if
2007 // int can represent all the values of the source type; otherwise,
2008 // the source rvalue can be converted to an rvalue of type unsigned
2010 if (FromType->isPromotableIntegerType() && !FromType->isBooleanType() &&
2011 !FromType->isEnumeralType()) {
2012 if (// We can promote any signed, promotable integer type to an int
2013 (FromType->isSignedIntegerType() ||
2014 // We can promote any unsigned integer type whose size is
2015 // less than int to an int.
2016 Context.getTypeSize(FromType) < Context.getTypeSize(ToType))) {
2017 return To->getKind() == BuiltinType::Int;
2020 return To->getKind() == BuiltinType::UInt;
2023 // C++11 [conv.prom]p3:
2024 // A prvalue of an unscoped enumeration type whose underlying type is not
2025 // fixed (7.2) can be converted to an rvalue a prvalue of the first of the
2026 // following types that can represent all the values of the enumeration
2027 // (i.e., the values in the range bmin to bmax as described in 7.2): int,
2028 // unsigned int, long int, unsigned long int, long long int, or unsigned
2029 // long long int. If none of the types in that list can represent all the
2030 // values of the enumeration, an rvalue a prvalue of an unscoped enumeration
2031 // type can be converted to an rvalue a prvalue of the extended integer type
2032 // with lowest integer conversion rank (4.13) greater than the rank of long
2033 // long in which all the values of the enumeration can be represented. If
2034 // there are two such extended types, the signed one is chosen.
2035 // C++11 [conv.prom]p4:
2036 // A prvalue of an unscoped enumeration type whose underlying type is fixed
2037 // can be converted to a prvalue of its underlying type. Moreover, if
2038 // integral promotion can be applied to its underlying type, a prvalue of an
2039 // unscoped enumeration type whose underlying type is fixed can also be
2040 // converted to a prvalue of the promoted underlying type.
2041 if (const EnumType *FromEnumType = FromType->getAs<EnumType>()) {
2042 // C++0x 7.2p9: Note that this implicit enum to int conversion is not
2043 // provided for a scoped enumeration.
2044 if (FromEnumType->getDecl()->isScoped())
2047 // We can perform an integral promotion to the underlying type of the enum,
2048 // even if that's not the promoted type. Note that the check for promoting
2049 // the underlying type is based on the type alone, and does not consider
2050 // the bitfield-ness of the actual source expression.
2051 if (FromEnumType->getDecl()->isFixed()) {
2052 QualType Underlying = FromEnumType->getDecl()->getIntegerType();
2053 return Context.hasSameUnqualifiedType(Underlying, ToType) ||
2054 IsIntegralPromotion(nullptr, Underlying, ToType);
2057 // We have already pre-calculated the promotion type, so this is trivial.
2058 if (ToType->isIntegerType() &&
2059 isCompleteType(From->getBeginLoc(), FromType))
2060 return Context.hasSameUnqualifiedType(
2061 ToType, FromEnumType->getDecl()->getPromotionType());
2063 // C++ [conv.prom]p5:
2064 // If the bit-field has an enumerated type, it is treated as any other
2065 // value of that type for promotion purposes.
2067 // ... so do not fall through into the bit-field checks below in C++.
2068 if (getLangOpts().CPlusPlus)
2072 // C++0x [conv.prom]p2:
2073 // A prvalue of type char16_t, char32_t, or wchar_t (3.9.1) can be converted
2074 // to an rvalue a prvalue of the first of the following types that can
2075 // represent all the values of its underlying type: int, unsigned int,
2076 // long int, unsigned long int, long long int, or unsigned long long int.
2077 // If none of the types in that list can represent all the values of its
2078 // underlying type, an rvalue a prvalue of type char16_t, char32_t,
2079 // or wchar_t can be converted to an rvalue a prvalue of its underlying
2081 if (FromType->isAnyCharacterType() && !FromType->isCharType() &&
2082 ToType->isIntegerType()) {
2083 // Determine whether the type we're converting from is signed or
2085 bool FromIsSigned = FromType->isSignedIntegerType();
2086 uint64_t FromSize = Context.getTypeSize(FromType);
2088 // The types we'll try to promote to, in the appropriate
2089 // order. Try each of these types.
2090 QualType PromoteTypes[6] = {
2091 Context.IntTy, Context.UnsignedIntTy,
2092 Context.LongTy, Context.UnsignedLongTy ,
2093 Context.LongLongTy, Context.UnsignedLongLongTy
2095 for (int Idx = 0; Idx < 6; ++Idx) {
2096 uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]);
2097 if (FromSize < ToSize ||
2098 (FromSize == ToSize &&
2099 FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) {
2100 // We found the type that we can promote to. If this is the
2101 // type we wanted, we have a promotion. Otherwise, no
2103 return Context.hasSameUnqualifiedType(ToType, PromoteTypes[Idx]);
2108 // An rvalue for an integral bit-field (9.6) can be converted to an
2109 // rvalue of type int if int can represent all the values of the
2110 // bit-field; otherwise, it can be converted to unsigned int if
2111 // unsigned int can represent all the values of the bit-field. If
2112 // the bit-field is larger yet, no integral promotion applies to
2113 // it. If the bit-field has an enumerated type, it is treated as any
2114 // other value of that type for promotion purposes (C++ 4.5p3).
2115 // FIXME: We should delay checking of bit-fields until we actually perform the
2118 // FIXME: In C, only bit-fields of types _Bool, int, or unsigned int may be
2119 // promoted, per C11 6.3.1.1/2. We promote all bit-fields (including enum
2120 // bit-fields and those whose underlying type is larger than int) for GCC
2123 if (FieldDecl *MemberDecl = From->getSourceBitField()) {
2124 llvm::APSInt BitWidth;
2125 if (FromType->isIntegralType(Context) &&
2126 MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) {
2127 llvm::APSInt ToSize(BitWidth.getBitWidth(), BitWidth.isUnsigned());
2128 ToSize = Context.getTypeSize(ToType);
2130 // Are we promoting to an int from a bitfield that fits in an int?
2131 if (BitWidth < ToSize ||
2132 (FromType->isSignedIntegerType() && BitWidth <= ToSize)) {
2133 return To->getKind() == BuiltinType::Int;
2136 // Are we promoting to an unsigned int from an unsigned bitfield
2137 // that fits into an unsigned int?
2138 if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize) {
2139 return To->getKind() == BuiltinType::UInt;
2147 // An rvalue of type bool can be converted to an rvalue of type int,
2148 // with false becoming zero and true becoming one (C++ 4.5p4).
2149 if (FromType->isBooleanType() && To->getKind() == BuiltinType::Int) {
2156 /// IsFloatingPointPromotion - Determines whether the conversion from
2157 /// FromType to ToType is a floating point promotion (C++ 4.6). If so,
2158 /// returns true and sets PromotedType to the promoted type.
2159 bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType) {
2160 if (const BuiltinType *FromBuiltin = FromType->getAs<BuiltinType>())
2161 if (const BuiltinType *ToBuiltin = ToType->getAs<BuiltinType>()) {
2162 /// An rvalue of type float can be converted to an rvalue of type
2163 /// double. (C++ 4.6p1).
2164 if (FromBuiltin->getKind() == BuiltinType::Float &&
2165 ToBuiltin->getKind() == BuiltinType::Double)
2169 // When a float is promoted to double or long double, or a
2170 // double is promoted to long double [...].
2171 if (!getLangOpts().CPlusPlus &&
2172 (FromBuiltin->getKind() == BuiltinType::Float ||
2173 FromBuiltin->getKind() == BuiltinType::Double) &&
2174 (ToBuiltin->getKind() == BuiltinType::LongDouble ||
2175 ToBuiltin->getKind() == BuiltinType::Float128))
2178 // Half can be promoted to float.
2179 if (!getLangOpts().NativeHalfType &&
2180 FromBuiltin->getKind() == BuiltinType::Half &&
2181 ToBuiltin->getKind() == BuiltinType::Float)
2188 /// Determine if a conversion is a complex promotion.
2190 /// A complex promotion is defined as a complex -> complex conversion
2191 /// where the conversion between the underlying real types is a
2192 /// floating-point or integral promotion.
2193 bool Sema::IsComplexPromotion(QualType FromType, QualType ToType) {
2194 const ComplexType *FromComplex = FromType->getAs<ComplexType>();
2198 const ComplexType *ToComplex = ToType->getAs<ComplexType>();
2202 return IsFloatingPointPromotion(FromComplex->getElementType(),
2203 ToComplex->getElementType()) ||
2204 IsIntegralPromotion(nullptr, FromComplex->getElementType(),
2205 ToComplex->getElementType());
2208 /// BuildSimilarlyQualifiedPointerType - In a pointer conversion from
2209 /// the pointer type FromPtr to a pointer to type ToPointee, with the
2210 /// same type qualifiers as FromPtr has on its pointee type. ToType,
2211 /// if non-empty, will be a pointer to ToType that may or may not have
2212 /// the right set of qualifiers on its pointee.
2215 BuildSimilarlyQualifiedPointerType(const Type *FromPtr,
2216 QualType ToPointee, QualType ToType,
2217 ASTContext &Context,
2218 bool StripObjCLifetime = false) {
2219 assert((FromPtr->getTypeClass() == Type::Pointer ||
2220 FromPtr->getTypeClass() == Type::ObjCObjectPointer) &&
2221 "Invalid similarly-qualified pointer type");
2223 /// Conversions to 'id' subsume cv-qualifier conversions.
2224 if (ToType->isObjCIdType() || ToType->isObjCQualifiedIdType())
2225 return ToType.getUnqualifiedType();
2227 QualType CanonFromPointee
2228 = Context.getCanonicalType(FromPtr->getPointeeType());
2229 QualType CanonToPointee = Context.getCanonicalType(ToPointee);
2230 Qualifiers Quals = CanonFromPointee.getQualifiers();
2232 if (StripObjCLifetime)
2233 Quals.removeObjCLifetime();
2235 // Exact qualifier match -> return the pointer type we're converting to.
2236 if (CanonToPointee.getLocalQualifiers() == Quals) {
2237 // ToType is exactly what we need. Return it.
2238 if (!ToType.isNull())
2239 return ToType.getUnqualifiedType();
2241 // Build a pointer to ToPointee. It has the right qualifiers
2243 if (isa<ObjCObjectPointerType>(ToType))
2244 return Context.getObjCObjectPointerType(ToPointee);
2245 return Context.getPointerType(ToPointee);
2248 // Just build a canonical type that has the right qualifiers.
2249 QualType QualifiedCanonToPointee
2250 = Context.getQualifiedType(CanonToPointee.getLocalUnqualifiedType(), Quals);
2252 if (isa<ObjCObjectPointerType>(ToType))
2253 return Context.getObjCObjectPointerType(QualifiedCanonToPointee);
2254 return Context.getPointerType(QualifiedCanonToPointee);
2257 static bool isNullPointerConstantForConversion(Expr *Expr,
2258 bool InOverloadResolution,
2259 ASTContext &Context) {
2260 // Handle value-dependent integral null pointer constants correctly.
2261 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903
2262 if (Expr->isValueDependent() && !Expr->isTypeDependent() &&
2263 Expr->getType()->isIntegerType() && !Expr->getType()->isEnumeralType())
2264 return !InOverloadResolution;
2266 return Expr->isNullPointerConstant(Context,
2267 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull
2268 : Expr::NPC_ValueDependentIsNull);
2271 /// IsPointerConversion - Determines whether the conversion of the
2272 /// expression From, which has the (possibly adjusted) type FromType,
2273 /// can be converted to the type ToType via a pointer conversion (C++
2274 /// 4.10). If so, returns true and places the converted type (that
2275 /// might differ from ToType in its cv-qualifiers at some level) into
2278 /// This routine also supports conversions to and from block pointers
2279 /// and conversions with Objective-C's 'id', 'id<protocols...>', and
2280 /// pointers to interfaces. FIXME: Once we've determined the
2281 /// appropriate overloading rules for Objective-C, we may want to
2282 /// split the Objective-C checks into a different routine; however,
2283 /// GCC seems to consider all of these conversions to be pointer
2284 /// conversions, so for now they live here. IncompatibleObjC will be
2285 /// set if the conversion is an allowed Objective-C conversion that
2286 /// should result in a warning.
2287 bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType,
2288 bool InOverloadResolution,
2289 QualType& ConvertedType,
2290 bool &IncompatibleObjC) {
2291 IncompatibleObjC = false;
2292 if (isObjCPointerConversion(FromType, ToType, ConvertedType,
2296 // Conversion from a null pointer constant to any Objective-C pointer type.
2297 if (ToType->isObjCObjectPointerType() &&
2298 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) {
2299 ConvertedType = ToType;
2303 // Blocks: Block pointers can be converted to void*.
2304 if (FromType->isBlockPointerType() && ToType->isPointerType() &&
2305 ToType->castAs<PointerType>()->getPointeeType()->isVoidType()) {
2306 ConvertedType = ToType;
2309 // Blocks: A null pointer constant can be converted to a block
2311 if (ToType->isBlockPointerType() &&
2312 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) {
2313 ConvertedType = ToType;
2317 // If the left-hand-side is nullptr_t, the right side can be a null
2318 // pointer constant.
2319 if (ToType->isNullPtrType() &&
2320 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) {
2321 ConvertedType = ToType;
2325 const PointerType* ToTypePtr = ToType->getAs<PointerType>();
2329 // A null pointer constant can be converted to a pointer type (C++ 4.10p1).
2330 if (isNullPointerConstantForConversion(From, InOverloadResolution, Context)) {
2331 ConvertedType = ToType;
2335 // Beyond this point, both types need to be pointers
2336 // , including objective-c pointers.
2337 QualType ToPointeeType = ToTypePtr->getPointeeType();
2338 if (FromType->isObjCObjectPointerType() && ToPointeeType->isVoidType() &&
2339 !getLangOpts().ObjCAutoRefCount) {
2340 ConvertedType = BuildSimilarlyQualifiedPointerType(
2341 FromType->getAs<ObjCObjectPointerType>(),
2346 const PointerType *FromTypePtr = FromType->getAs<PointerType>();
2350 QualType FromPointeeType = FromTypePtr->getPointeeType();
2352 // If the unqualified pointee types are the same, this can't be a
2353 // pointer conversion, so don't do all of the work below.
2354 if (Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType))
2357 // An rvalue of type "pointer to cv T," where T is an object type,
2358 // can be converted to an rvalue of type "pointer to cv void" (C++
2360 if (FromPointeeType->isIncompleteOrObjectType() &&
2361 ToPointeeType->isVoidType()) {
2362 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2365 /*StripObjCLifetime=*/true);
2369 // MSVC allows implicit function to void* type conversion.
2370 if (getLangOpts().MSVCCompat && FromPointeeType->isFunctionType() &&
2371 ToPointeeType->isVoidType()) {
2372 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2378 // When we're overloading in C, we allow a special kind of pointer
2379 // conversion for compatible-but-not-identical pointee types.
2380 if (!getLangOpts().CPlusPlus &&
2381 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) {
2382 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2388 // C++ [conv.ptr]p3:
2390 // An rvalue of type "pointer to cv D," where D is a class type,
2391 // can be converted to an rvalue of type "pointer to cv B," where
2392 // B is a base class (clause 10) of D. If B is an inaccessible
2393 // (clause 11) or ambiguous (10.2) base class of D, a program that
2394 // necessitates this conversion is ill-formed. The result of the
2395 // conversion is a pointer to the base class sub-object of the
2396 // derived class object. The null pointer value is converted to
2397 // the null pointer value of the destination type.
2399 // Note that we do not check for ambiguity or inaccessibility
2400 // here. That is handled by CheckPointerConversion.
2401 if (getLangOpts().CPlusPlus && FromPointeeType->isRecordType() &&
2402 ToPointeeType->isRecordType() &&
2403 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType) &&
2404 IsDerivedFrom(From->getBeginLoc(), FromPointeeType, ToPointeeType)) {
2405 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2411 if (FromPointeeType->isVectorType() && ToPointeeType->isVectorType() &&
2412 Context.areCompatibleVectorTypes(FromPointeeType, ToPointeeType)) {
2413 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2422 /// Adopt the given qualifiers for the given type.
2423 static QualType AdoptQualifiers(ASTContext &Context, QualType T, Qualifiers Qs){
2424 Qualifiers TQs = T.getQualifiers();
2426 // Check whether qualifiers already match.
2430 if (Qs.compatiblyIncludes(TQs))
2431 return Context.getQualifiedType(T, Qs);
2433 return Context.getQualifiedType(T.getUnqualifiedType(), Qs);
2436 /// isObjCPointerConversion - Determines whether this is an
2437 /// Objective-C pointer conversion. Subroutine of IsPointerConversion,
2438 /// with the same arguments and return values.
2439 bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType,
2440 QualType& ConvertedType,
2441 bool &IncompatibleObjC) {
2442 if (!getLangOpts().ObjC)
2445 // The set of qualifiers on the type we're converting from.
2446 Qualifiers FromQualifiers = FromType.getQualifiers();
2448 // First, we handle all conversions on ObjC object pointer types.
2449 const ObjCObjectPointerType* ToObjCPtr =
2450 ToType->getAs<ObjCObjectPointerType>();
2451 const ObjCObjectPointerType *FromObjCPtr =
2452 FromType->getAs<ObjCObjectPointerType>();
2454 if (ToObjCPtr && FromObjCPtr) {
2455 // If the pointee types are the same (ignoring qualifications),
2456 // then this is not a pointer conversion.
2457 if (Context.hasSameUnqualifiedType(ToObjCPtr->getPointeeType(),
2458 FromObjCPtr->getPointeeType()))
2461 // Conversion between Objective-C pointers.
2462 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) {
2463 const ObjCInterfaceType* LHS = ToObjCPtr->getInterfaceType();
2464 const ObjCInterfaceType* RHS = FromObjCPtr->getInterfaceType();
2465 if (getLangOpts().CPlusPlus && LHS && RHS &&
2466 !ToObjCPtr->getPointeeType().isAtLeastAsQualifiedAs(
2467 FromObjCPtr->getPointeeType()))
2469 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr,
2470 ToObjCPtr->getPointeeType(),
2472 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers);
2476 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) {
2477 // Okay: this is some kind of implicit downcast of Objective-C
2478 // interfaces, which is permitted. However, we're going to
2479 // complain about it.
2480 IncompatibleObjC = true;
2481 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr,
2482 ToObjCPtr->getPointeeType(),
2484 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers);
2488 // Beyond this point, both types need to be C pointers or block pointers.
2489 QualType ToPointeeType;
2490 if (const PointerType *ToCPtr = ToType->getAs<PointerType>())
2491 ToPointeeType = ToCPtr->getPointeeType();
2492 else if (const BlockPointerType *ToBlockPtr =
2493 ToType->getAs<BlockPointerType>()) {
2494 // Objective C++: We're able to convert from a pointer to any object
2495 // to a block pointer type.
2496 if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) {
2497 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers);
2500 ToPointeeType = ToBlockPtr->getPointeeType();
2502 else if (FromType->getAs<BlockPointerType>() &&
2503 ToObjCPtr && ToObjCPtr->isObjCBuiltinType()) {
2504 // Objective C++: We're able to convert from a block pointer type to a
2505 // pointer to any object.
2506 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers);
2512 QualType FromPointeeType;
2513 if (const PointerType *FromCPtr = FromType->getAs<PointerType>())
2514 FromPointeeType = FromCPtr->getPointeeType();
2515 else if (const BlockPointerType *FromBlockPtr =
2516 FromType->getAs<BlockPointerType>())
2517 FromPointeeType = FromBlockPtr->getPointeeType();
2521 // If we have pointers to pointers, recursively check whether this
2522 // is an Objective-C conversion.
2523 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() &&
2524 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType,
2525 IncompatibleObjC)) {
2526 // We always complain about this conversion.
2527 IncompatibleObjC = true;
2528 ConvertedType = Context.getPointerType(ConvertedType);
2529 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers);
2532 // Allow conversion of pointee being objective-c pointer to another one;
2534 if (FromPointeeType->getAs<ObjCObjectPointerType>() &&
2535 ToPointeeType->getAs<ObjCObjectPointerType>() &&
2536 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType,
2537 IncompatibleObjC)) {
2539 ConvertedType = Context.getPointerType(ConvertedType);
2540 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers);
2544 // If we have pointers to functions or blocks, check whether the only
2545 // differences in the argument and result types are in Objective-C
2546 // pointer conversions. If so, we permit the conversion (but
2547 // complain about it).
2548 const FunctionProtoType *FromFunctionType
2549 = FromPointeeType->getAs<FunctionProtoType>();
2550 const FunctionProtoType *ToFunctionType
2551 = ToPointeeType->getAs<FunctionProtoType>();
2552 if (FromFunctionType && ToFunctionType) {
2553 // If the function types are exactly the same, this isn't an
2554 // Objective-C pointer conversion.
2555 if (Context.getCanonicalType(FromPointeeType)
2556 == Context.getCanonicalType(ToPointeeType))
2559 // Perform the quick checks that will tell us whether these
2560 // function types are obviously different.
2561 if (FromFunctionType->getNumParams() != ToFunctionType->getNumParams() ||
2562 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() ||
2563 FromFunctionType->getMethodQuals() != ToFunctionType->getMethodQuals())
2566 bool HasObjCConversion = false;
2567 if (Context.getCanonicalType(FromFunctionType->getReturnType()) ==
2568 Context.getCanonicalType(ToFunctionType->getReturnType())) {
2569 // Okay, the types match exactly. Nothing to do.
2570 } else if (isObjCPointerConversion(FromFunctionType->getReturnType(),
2571 ToFunctionType->getReturnType(),
2572 ConvertedType, IncompatibleObjC)) {
2573 // Okay, we have an Objective-C pointer conversion.
2574 HasObjCConversion = true;
2576 // Function types are too different. Abort.
2580 // Check argument types.
2581 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumParams();
2582 ArgIdx != NumArgs; ++ArgIdx) {
2583 QualType FromArgType = FromFunctionType->getParamType(ArgIdx);
2584 QualType ToArgType = ToFunctionType->getParamType(ArgIdx);
2585 if (Context.getCanonicalType(FromArgType)
2586 == Context.getCanonicalType(ToArgType)) {
2587 // Okay, the types match exactly. Nothing to do.
2588 } else if (isObjCPointerConversion(FromArgType, ToArgType,
2589 ConvertedType, IncompatibleObjC)) {
2590 // Okay, we have an Objective-C pointer conversion.
2591 HasObjCConversion = true;
2593 // Argument types are too different. Abort.
2598 if (HasObjCConversion) {
2599 // We had an Objective-C conversion. Allow this pointer
2600 // conversion, but complain about it.
2601 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers);
2602 IncompatibleObjC = true;
2610 /// Determine whether this is an Objective-C writeback conversion,
2611 /// used for parameter passing when performing automatic reference counting.
2613 /// \param FromType The type we're converting form.
2615 /// \param ToType The type we're converting to.
2617 /// \param ConvertedType The type that will be produced after applying
2618 /// this conversion.
2619 bool Sema::isObjCWritebackConversion(QualType FromType, QualType ToType,
2620 QualType &ConvertedType) {
2621 if (!getLangOpts().ObjCAutoRefCount ||
2622 Context.hasSameUnqualifiedType(FromType, ToType))
2625 // Parameter must be a pointer to __autoreleasing (with no other qualifiers).
2627 if (const PointerType *ToPointer = ToType->getAs<PointerType>())
2628 ToPointee = ToPointer->getPointeeType();
2632 Qualifiers ToQuals = ToPointee.getQualifiers();
2633 if (!ToPointee->isObjCLifetimeType() ||
2634 ToQuals.getObjCLifetime() != Qualifiers::OCL_Autoreleasing ||
2635 !ToQuals.withoutObjCLifetime().empty())
2638 // Argument must be a pointer to __strong to __weak.
2639 QualType FromPointee;
2640 if (const PointerType *FromPointer = FromType->getAs<PointerType>())
2641 FromPointee = FromPointer->getPointeeType();
2645 Qualifiers FromQuals = FromPointee.getQualifiers();
2646 if (!FromPointee->isObjCLifetimeType() ||
2647 (FromQuals.getObjCLifetime() != Qualifiers::OCL_Strong &&
2648 FromQuals.getObjCLifetime() != Qualifiers::OCL_Weak))
2651 // Make sure that we have compatible qualifiers.
2652 FromQuals.setObjCLifetime(Qualifiers::OCL_Autoreleasing);
2653 if (!ToQuals.compatiblyIncludes(FromQuals))
2656 // Remove qualifiers from the pointee type we're converting from; they
2657 // aren't used in the compatibility check belong, and we'll be adding back
2658 // qualifiers (with __autoreleasing) if the compatibility check succeeds.
2659 FromPointee = FromPointee.getUnqualifiedType();
2661 // The unqualified form of the pointee types must be compatible.
2662 ToPointee = ToPointee.getUnqualifiedType();
2663 bool IncompatibleObjC;
2664 if (Context.typesAreCompatible(FromPointee, ToPointee))
2665 FromPointee = ToPointee;
2666 else if (!isObjCPointerConversion(FromPointee, ToPointee, FromPointee,
2670 /// Construct the type we're converting to, which is a pointer to
2671 /// __autoreleasing pointee.
2672 FromPointee = Context.getQualifiedType(FromPointee, FromQuals);
2673 ConvertedType = Context.getPointerType(FromPointee);
2677 bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType,
2678 QualType& ConvertedType) {
2679 QualType ToPointeeType;
2680 if (const BlockPointerType *ToBlockPtr =
2681 ToType->getAs<BlockPointerType>())
2682 ToPointeeType = ToBlockPtr->getPointeeType();
2686 QualType FromPointeeType;
2687 if (const BlockPointerType *FromBlockPtr =
2688 FromType->getAs<BlockPointerType>())
2689 FromPointeeType = FromBlockPtr->getPointeeType();
2692 // We have pointer to blocks, check whether the only
2693 // differences in the argument and result types are in Objective-C
2694 // pointer conversions. If so, we permit the conversion.
2696 const FunctionProtoType *FromFunctionType
2697 = FromPointeeType->getAs<FunctionProtoType>();
2698 const FunctionProtoType *ToFunctionType
2699 = ToPointeeType->getAs<FunctionProtoType>();
2701 if (!FromFunctionType || !ToFunctionType)
2704 if (Context.hasSameType(FromPointeeType, ToPointeeType))
2707 // Perform the quick checks that will tell us whether these
2708 // function types are obviously different.
2709 if (FromFunctionType->getNumParams() != ToFunctionType->getNumParams() ||
2710 FromFunctionType->isVariadic() != ToFunctionType->isVariadic())
2713 FunctionType::ExtInfo FromEInfo = FromFunctionType->getExtInfo();
2714 FunctionType::ExtInfo ToEInfo = ToFunctionType->getExtInfo();
2715 if (FromEInfo != ToEInfo)
2718 bool IncompatibleObjC = false;
2719 if (Context.hasSameType(FromFunctionType->getReturnType(),
2720 ToFunctionType->getReturnType())) {
2721 // Okay, the types match exactly. Nothing to do.
2723 QualType RHS = FromFunctionType->getReturnType();
2724 QualType LHS = ToFunctionType->getReturnType();
2725 if ((!getLangOpts().CPlusPlus || !RHS->isRecordType()) &&
2726 !RHS.hasQualifiers() && LHS.hasQualifiers())
2727 LHS = LHS.getUnqualifiedType();
2729 if (Context.hasSameType(RHS,LHS)) {
2731 } else if (isObjCPointerConversion(RHS, LHS,
2732 ConvertedType, IncompatibleObjC)) {
2733 if (IncompatibleObjC)
2735 // Okay, we have an Objective-C pointer conversion.
2741 // Check argument types.
2742 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumParams();
2743 ArgIdx != NumArgs; ++ArgIdx) {
2744 IncompatibleObjC = false;
2745 QualType FromArgType = FromFunctionType->getParamType(ArgIdx);
2746 QualType ToArgType = ToFunctionType->getParamType(ArgIdx);
2747 if (Context.hasSameType(FromArgType, ToArgType)) {
2748 // Okay, the types match exactly. Nothing to do.
2749 } else if (isObjCPointerConversion(ToArgType, FromArgType,
2750 ConvertedType, IncompatibleObjC)) {
2751 if (IncompatibleObjC)
2753 // Okay, we have an Objective-C pointer conversion.
2755 // Argument types are too different. Abort.
2759 SmallVector<FunctionProtoType::ExtParameterInfo, 4> NewParamInfos;
2760 bool CanUseToFPT, CanUseFromFPT;
2761 if (!Context.mergeExtParameterInfo(ToFunctionType, FromFunctionType,
2762 CanUseToFPT, CanUseFromFPT,
2766 ConvertedType = ToType;
2774 ft_parameter_mismatch,
2776 ft_qualifer_mismatch,
2780 /// Attempts to get the FunctionProtoType from a Type. Handles
2781 /// MemberFunctionPointers properly.
2782 static const FunctionProtoType *tryGetFunctionProtoType(QualType FromType) {
2783 if (auto *FPT = FromType->getAs<FunctionProtoType>())
2786 if (auto *MPT = FromType->getAs<MemberPointerType>())
2787 return MPT->getPointeeType()->getAs<FunctionProtoType>();
2792 /// HandleFunctionTypeMismatch - Gives diagnostic information for differeing
2793 /// function types. Catches different number of parameter, mismatch in
2794 /// parameter types, and different return types.
2795 void Sema::HandleFunctionTypeMismatch(PartialDiagnostic &PDiag,
2796 QualType FromType, QualType ToType) {
2797 // If either type is not valid, include no extra info.
2798 if (FromType.isNull() || ToType.isNull()) {
2799 PDiag << ft_default;
2803 // Get the function type from the pointers.
2804 if (FromType->isMemberPointerType() && ToType->isMemberPointerType()) {
2805 const MemberPointerType *FromMember = FromType->getAs<MemberPointerType>(),
2806 *ToMember = ToType->getAs<MemberPointerType>();
2807 if (!Context.hasSameType(FromMember->getClass(), ToMember->getClass())) {
2808 PDiag << ft_different_class << QualType(ToMember->getClass(), 0)
2809 << QualType(FromMember->getClass(), 0);
2812 FromType = FromMember->getPointeeType();
2813 ToType = ToMember->getPointeeType();
2816 if (FromType->isPointerType())
2817 FromType = FromType->getPointeeType();
2818 if (ToType->isPointerType())
2819 ToType = ToType->getPointeeType();
2821 // Remove references.
2822 FromType = FromType.getNonReferenceType();
2823 ToType = ToType.getNonReferenceType();
2825 // Don't print extra info for non-specialized template functions.
2826 if (FromType->isInstantiationDependentType() &&
2827 !FromType->getAs<TemplateSpecializationType>()) {
2828 PDiag << ft_default;
2832 // No extra info for same types.
2833 if (Context.hasSameType(FromType, ToType)) {
2834 PDiag << ft_default;
2838 const FunctionProtoType *FromFunction = tryGetFunctionProtoType(FromType),
2839 *ToFunction = tryGetFunctionProtoType(ToType);
2841 // Both types need to be function types.
2842 if (!FromFunction || !ToFunction) {
2843 PDiag << ft_default;
2847 if (FromFunction->getNumParams() != ToFunction->getNumParams()) {
2848 PDiag << ft_parameter_arity << ToFunction->getNumParams()
2849 << FromFunction->getNumParams();
2853 // Handle different parameter types.
2855 if (!FunctionParamTypesAreEqual(FromFunction, ToFunction, &ArgPos)) {
2856 PDiag << ft_parameter_mismatch << ArgPos + 1
2857 << ToFunction->getParamType(ArgPos)
2858 << FromFunction->getParamType(ArgPos);
2862 // Handle different return type.
2863 if (!Context.hasSameType(FromFunction->getReturnType(),
2864 ToFunction->getReturnType())) {
2865 PDiag << ft_return_type << ToFunction->getReturnType()
2866 << FromFunction->getReturnType();
2870 if (FromFunction->getMethodQuals() != ToFunction->getMethodQuals()) {
2871 PDiag << ft_qualifer_mismatch << ToFunction->getMethodQuals()
2872 << FromFunction->getMethodQuals();
2876 // Handle exception specification differences on canonical type (in C++17
2878 if (cast<FunctionProtoType>(FromFunction->getCanonicalTypeUnqualified())
2880 cast<FunctionProtoType>(ToFunction->getCanonicalTypeUnqualified())
2882 PDiag << ft_noexcept;
2886 // Unable to find a difference, so add no extra info.
2887 PDiag << ft_default;
2890 /// FunctionParamTypesAreEqual - This routine checks two function proto types
2891 /// for equality of their argument types. Caller has already checked that
2892 /// they have same number of arguments. If the parameters are different,
2893 /// ArgPos will have the parameter index of the first different parameter.
2894 bool Sema::FunctionParamTypesAreEqual(const FunctionProtoType *OldType,
2895 const FunctionProtoType *NewType,
2897 for (FunctionProtoType::param_type_iterator O = OldType->param_type_begin(),
2898 N = NewType->param_type_begin(),
2899 E = OldType->param_type_end();
2900 O && (O != E); ++O, ++N) {
2901 if (!Context.hasSameType(O->getUnqualifiedType(),
2902 N->getUnqualifiedType())) {
2904 *ArgPos = O - OldType->param_type_begin();
2911 /// CheckPointerConversion - Check the pointer conversion from the
2912 /// expression From to the type ToType. This routine checks for
2913 /// ambiguous or inaccessible derived-to-base pointer
2914 /// conversions for which IsPointerConversion has already returned
2915 /// true. It returns true and produces a diagnostic if there was an
2916 /// error, or returns false otherwise.
2917 bool Sema::CheckPointerConversion(Expr *From, QualType ToType,
2919 CXXCastPath& BasePath,
2920 bool IgnoreBaseAccess,
2922 QualType FromType = From->getType();
2923 bool IsCStyleOrFunctionalCast = IgnoreBaseAccess;
2927 if (Diagnose && !IsCStyleOrFunctionalCast && !FromType->isAnyPointerType() &&
2928 From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull) ==
2929 Expr::NPCK_ZeroExpression) {
2930 if (Context.hasSameUnqualifiedType(From->getType(), Context.BoolTy))
2931 DiagRuntimeBehavior(From->getExprLoc(), From,
2932 PDiag(diag::warn_impcast_bool_to_null_pointer)
2933 << ToType << From->getSourceRange());
2934 else if (!isUnevaluatedContext())
2935 Diag(From->getExprLoc(), diag::warn_non_literal_null_pointer)
2936 << ToType << From->getSourceRange();
2938 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) {
2939 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) {
2940 QualType FromPointeeType = FromPtrType->getPointeeType(),
2941 ToPointeeType = ToPtrType->getPointeeType();
2943 if (FromPointeeType->isRecordType() && ToPointeeType->isRecordType() &&
2944 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) {
2945 // We must have a derived-to-base conversion. Check an
2946 // ambiguous or inaccessible conversion.
2947 unsigned InaccessibleID = 0;
2948 unsigned AmbigiousID = 0;
2950 InaccessibleID = diag::err_upcast_to_inaccessible_base;
2951 AmbigiousID = diag::err_ambiguous_derived_to_base_conv;
2953 if (CheckDerivedToBaseConversion(
2954 FromPointeeType, ToPointeeType, InaccessibleID, AmbigiousID,
2955 From->getExprLoc(), From->getSourceRange(), DeclarationName(),
2956 &BasePath, IgnoreBaseAccess))
2959 // The conversion was successful.
2960 Kind = CK_DerivedToBase;
2963 if (Diagnose && !IsCStyleOrFunctionalCast &&
2964 FromPointeeType->isFunctionType() && ToPointeeType->isVoidType()) {
2965 assert(getLangOpts().MSVCCompat &&
2966 "this should only be possible with MSVCCompat!");
2967 Diag(From->getExprLoc(), diag::ext_ms_impcast_fn_obj)
2968 << From->getSourceRange();
2971 } else if (const ObjCObjectPointerType *ToPtrType =
2972 ToType->getAs<ObjCObjectPointerType>()) {
2973 if (const ObjCObjectPointerType *FromPtrType =
2974 FromType->getAs<ObjCObjectPointerType>()) {
2975 // Objective-C++ conversions are always okay.
2976 // FIXME: We should have a different class of conversions for the
2977 // Objective-C++ implicit conversions.
2978 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType())
2980 } else if (FromType->isBlockPointerType()) {
2981 Kind = CK_BlockPointerToObjCPointerCast;
2983 Kind = CK_CPointerToObjCPointerCast;
2985 } else if (ToType->isBlockPointerType()) {
2986 if (!FromType->isBlockPointerType())
2987 Kind = CK_AnyPointerToBlockPointerCast;
2990 // We shouldn't fall into this case unless it's valid for other
2992 if (From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull))
2993 Kind = CK_NullToPointer;
2998 /// IsMemberPointerConversion - Determines whether the conversion of the
2999 /// expression From, which has the (possibly adjusted) type FromType, can be
3000 /// converted to the type ToType via a member pointer conversion (C++ 4.11).
3001 /// If so, returns true and places the converted type (that might differ from
3002 /// ToType in its cv-qualifiers at some level) into ConvertedType.
3003 bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType,
3005 bool InOverloadResolution,
3006 QualType &ConvertedType) {
3007 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>();
3011 // A null pointer constant can be converted to a member pointer (C++ 4.11p1)
3012 if (From->isNullPointerConstant(Context,
3013 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull
3014 : Expr::NPC_ValueDependentIsNull)) {
3015 ConvertedType = ToType;
3019 // Otherwise, both types have to be member pointers.
3020 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>();
3024 // A pointer to member of B can be converted to a pointer to member of D,
3025 // where D is derived from B (C++ 4.11p2).
3026 QualType FromClass(FromTypePtr->getClass(), 0);
3027 QualType ToClass(ToTypePtr->getClass(), 0);
3029 if (!Context.hasSameUnqualifiedType(FromClass, ToClass) &&
3030 IsDerivedFrom(From->getBeginLoc(), ToClass, FromClass)) {
3031 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(),
3032 ToClass.getTypePtr());
3039 /// CheckMemberPointerConversion - Check the member pointer conversion from the
3040 /// expression From to the type ToType. This routine checks for ambiguous or
3041 /// virtual or inaccessible base-to-derived member pointer conversions
3042 /// for which IsMemberPointerConversion has already returned true. It returns
3043 /// true and produces a diagnostic if there was an error, or returns false
3045 bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType,
3047 CXXCastPath &BasePath,
3048 bool IgnoreBaseAccess) {
3049 QualType FromType = From->getType();
3050 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>();
3052 // This must be a null pointer to member pointer conversion
3053 assert(From->isNullPointerConstant(Context,
3054 Expr::NPC_ValueDependentIsNull) &&
3055 "Expr must be null pointer constant!");
3056 Kind = CK_NullToMemberPointer;
3060 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>();
3061 assert(ToPtrType && "No member pointer cast has a target type "
3062 "that is not a member pointer.");
3064 QualType FromClass = QualType(FromPtrType->getClass(), 0);
3065 QualType ToClass = QualType(ToPtrType->getClass(), 0);
3067 // FIXME: What about dependent types?
3068 assert(FromClass->isRecordType() && "Pointer into non-class.");
3069 assert(ToClass->isRecordType() && "Pointer into non-class.");
3071 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
3072 /*DetectVirtual=*/true);
3073 bool DerivationOkay =
3074 IsDerivedFrom(From->getBeginLoc(), ToClass, FromClass, Paths);
3075 assert(DerivationOkay &&
3076 "Should not have been called if derivation isn't OK.");
3077 (void)DerivationOkay;
3079 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass).
3080 getUnqualifiedType())) {
3081 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
3082 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv)
3083 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange();
3087 if (const RecordType *VBase = Paths.getDetectedVirtual()) {
3088 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual)
3089 << FromClass << ToClass << QualType(VBase, 0)
3090 << From->getSourceRange();
3094 if (!IgnoreBaseAccess)
3095 CheckBaseClassAccess(From->getExprLoc(), FromClass, ToClass,
3097 diag::err_downcast_from_inaccessible_base);
3099 // Must be a base to derived member conversion.
3100 BuildBasePathArray(Paths, BasePath);
3101 Kind = CK_BaseToDerivedMemberPointer;
3105 /// Determine whether the lifetime conversion between the two given
3106 /// qualifiers sets is nontrivial.
3107 static bool isNonTrivialObjCLifetimeConversion(Qualifiers FromQuals,
3108 Qualifiers ToQuals) {
3109 // Converting anything to const __unsafe_unretained is trivial.
3110 if (ToQuals.hasConst() &&
3111 ToQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone)
3117 /// IsQualificationConversion - Determines whether the conversion from
3118 /// an rvalue of type FromType to ToType is a qualification conversion
3121 /// \param ObjCLifetimeConversion Output parameter that will be set to indicate
3122 /// when the qualification conversion involves a change in the Objective-C
3123 /// object lifetime.
3125 Sema::IsQualificationConversion(QualType FromType, QualType ToType,
3126 bool CStyle, bool &ObjCLifetimeConversion) {
3127 FromType = Context.getCanonicalType(FromType);
3128 ToType = Context.getCanonicalType(ToType);
3129 ObjCLifetimeConversion = false;
3131 // If FromType and ToType are the same type, this is not a
3132 // qualification conversion.
3133 if (FromType.getUnqualifiedType() == ToType.getUnqualifiedType())
3137 // A conversion can add cv-qualifiers at levels other than the first
3138 // in multi-level pointers, subject to the following rules: [...]
3139 bool PreviousToQualsIncludeConst = true;
3140 bool UnwrappedAnyPointer = false;
3141 while (Context.UnwrapSimilarTypes(FromType, ToType)) {
3142 // Within each iteration of the loop, we check the qualifiers to
3143 // determine if this still looks like a qualification
3144 // conversion. Then, if all is well, we unwrap one more level of
3145 // pointers or pointers-to-members and do it all again
3146 // until there are no more pointers or pointers-to-members left to
3148 UnwrappedAnyPointer = true;
3150 Qualifiers FromQuals = FromType.getQualifiers();
3151 Qualifiers ToQuals = ToType.getQualifiers();
3153 // Ignore __unaligned qualifier if this type is void.
3154 if (ToType.getUnqualifiedType()->isVoidType())
3155 FromQuals.removeUnaligned();
3158 // Check Objective-C lifetime conversions.
3159 if (FromQuals.getObjCLifetime() != ToQuals.getObjCLifetime() &&
3160 UnwrappedAnyPointer) {
3161 if (ToQuals.compatiblyIncludesObjCLifetime(FromQuals)) {
3162 if (isNonTrivialObjCLifetimeConversion(FromQuals, ToQuals))
3163 ObjCLifetimeConversion = true;
3164 FromQuals.removeObjCLifetime();
3165 ToQuals.removeObjCLifetime();
3167 // Qualification conversions cannot cast between different
3168 // Objective-C lifetime qualifiers.
3173 // Allow addition/removal of GC attributes but not changing GC attributes.
3174 if (FromQuals.getObjCGCAttr() != ToQuals.getObjCGCAttr() &&
3175 (!FromQuals.hasObjCGCAttr() || !ToQuals.hasObjCGCAttr())) {
3176 FromQuals.removeObjCGCAttr();
3177 ToQuals.removeObjCGCAttr();
3180 // -- for every j > 0, if const is in cv 1,j then const is in cv
3181 // 2,j, and similarly for volatile.
3182 if (!CStyle && !ToQuals.compatiblyIncludes(FromQuals))
3185 // -- if the cv 1,j and cv 2,j are different, then const is in
3186 // every cv for 0 < k < j.
3187 if (!CStyle && FromQuals.getCVRQualifiers() != ToQuals.getCVRQualifiers()
3188 && !PreviousToQualsIncludeConst)
3191 // Keep track of whether all prior cv-qualifiers in the "to" type
3193 PreviousToQualsIncludeConst
3194 = PreviousToQualsIncludeConst && ToQuals.hasConst();
3197 // Allows address space promotion by language rules implemented in
3198 // Type::Qualifiers::isAddressSpaceSupersetOf.
3199 Qualifiers FromQuals = FromType.getQualifiers();
3200 Qualifiers ToQuals = ToType.getQualifiers();
3201 if (!ToQuals.isAddressSpaceSupersetOf(FromQuals) &&
3202 !FromQuals.isAddressSpaceSupersetOf(ToQuals)) {
3206 // We are left with FromType and ToType being the pointee types
3207 // after unwrapping the original FromType and ToType the same number
3208 // of types. If we unwrapped any pointers, and if FromType and
3209 // ToType have the same unqualified type (since we checked
3210 // qualifiers above), then this is a qualification conversion.
3211 return UnwrappedAnyPointer && Context.hasSameUnqualifiedType(FromType,ToType);
3214 /// - Determine whether this is a conversion from a scalar type to an
3217 /// If successful, updates \c SCS's second and third steps in the conversion
3218 /// sequence to finish the conversion.
3219 static bool tryAtomicConversion(Sema &S, Expr *From, QualType ToType,
3220 bool InOverloadResolution,
3221 StandardConversionSequence &SCS,
3223 const AtomicType *ToAtomic = ToType->getAs<AtomicType>();
3227 StandardConversionSequence InnerSCS;
3228 if (!IsStandardConversion(S, From, ToAtomic->getValueType(),
3229 InOverloadResolution, InnerSCS,
3230 CStyle, /*AllowObjCWritebackConversion=*/false))
3233 SCS.Second = InnerSCS.Second;
3234 SCS.setToType(1, InnerSCS.getToType(1));
3235 SCS.Third = InnerSCS.Third;
3236 SCS.QualificationIncludesObjCLifetime
3237 = InnerSCS.QualificationIncludesObjCLifetime;
3238 SCS.setToType(2, InnerSCS.getToType(2));
3242 static bool isFirstArgumentCompatibleWithType(ASTContext &Context,
3243 CXXConstructorDecl *Constructor,
3245 const FunctionProtoType *CtorType =
3246 Constructor->getType()->getAs<FunctionProtoType>();
3247 if (CtorType->getNumParams() > 0) {
3248 QualType FirstArg = CtorType->getParamType(0);
3249 if (Context.hasSameUnqualifiedType(Type, FirstArg.getNonReferenceType()))
3255 static OverloadingResult
3256 IsInitializerListConstructorConversion(Sema &S, Expr *From, QualType ToType,
3258 UserDefinedConversionSequence &User,
3259 OverloadCandidateSet &CandidateSet,
3260 bool AllowExplicit) {
3261 CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
3262 for (auto *D : S.LookupConstructors(To)) {
3263 auto Info = getConstructorInfo(D);
3267 bool Usable = !Info.Constructor->isInvalidDecl() &&
3268 S.isInitListConstructor(Info.Constructor) &&
3269 (AllowExplicit || !Info.Constructor->isExplicit());
3271 // If the first argument is (a reference to) the target type,
3272 // suppress conversions.
3273 bool SuppressUserConversions = isFirstArgumentCompatibleWithType(
3274 S.Context, Info.Constructor, ToType);
3275 if (Info.ConstructorTmpl)
3276 S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
3277 /*ExplicitArgs*/ nullptr, From,
3278 CandidateSet, SuppressUserConversions,
3279 /*PartialOverloading*/ false,
3282 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl, From,
3283 CandidateSet, SuppressUserConversions,
3284 /*PartialOverloading*/ false, AllowExplicit);
3288 bool HadMultipleCandidates = (CandidateSet.size() > 1);
3290 OverloadCandidateSet::iterator Best;
3291 switch (auto Result =
3292 CandidateSet.BestViableFunction(S, From->getBeginLoc(), Best)) {
3295 // Record the standard conversion we used and the conversion function.
3296 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function);
3297 QualType ThisType = Constructor->getThisType();
3298 // Initializer lists don't have conversions as such.
3299 User.Before.setAsIdentityConversion();
3300 User.HadMultipleCandidates = HadMultipleCandidates;
3301 User.ConversionFunction = Constructor;
3302 User.FoundConversionFunction = Best->FoundDecl;
3303 User.After.setAsIdentityConversion();
3304 User.After.setFromType(ThisType->castAs<PointerType>()->getPointeeType());
3305 User.After.setAllToTypes(ToType);
3309 case OR_No_Viable_Function:
3310 return OR_No_Viable_Function;
3312 return OR_Ambiguous;
3315 llvm_unreachable("Invalid OverloadResult!");
3318 /// Determines whether there is a user-defined conversion sequence
3319 /// (C++ [over.ics.user]) that converts expression From to the type
3320 /// ToType. If such a conversion exists, User will contain the
3321 /// user-defined conversion sequence that performs such a conversion
3322 /// and this routine will return true. Otherwise, this routine returns
3323 /// false and User is unspecified.
3325 /// \param AllowExplicit true if the conversion should consider C++0x
3326 /// "explicit" conversion functions as well as non-explicit conversion
3327 /// functions (C++0x [class.conv.fct]p2).
3329 /// \param AllowObjCConversionOnExplicit true if the conversion should
3330 /// allow an extra Objective-C pointer conversion on uses of explicit
3331 /// constructors. Requires \c AllowExplicit to also be set.
3332 static OverloadingResult
3333 IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
3334 UserDefinedConversionSequence &User,
3335 OverloadCandidateSet &CandidateSet,
3337 bool AllowObjCConversionOnExplicit) {
3338 assert(AllowExplicit || !AllowObjCConversionOnExplicit);
3339 CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
3341 // Whether we will only visit constructors.
3342 bool ConstructorsOnly = false;
3344 // If the type we are conversion to is a class type, enumerate its
3346 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) {
3347 // C++ [over.match.ctor]p1:
3348 // When objects of class type are direct-initialized (8.5), or
3349 // copy-initialized from an expression of the same or a
3350 // derived class type (8.5), overload resolution selects the
3351 // constructor. [...] For copy-initialization, the candidate
3352 // functions are all the converting constructors (12.3.1) of
3353 // that class. The argument list is the expression-list within
3354 // the parentheses of the initializer.
3355 if (S.Context.hasSameUnqualifiedType(ToType, From->getType()) ||
3356 (From->getType()->getAs<RecordType>() &&
3357 S.IsDerivedFrom(From->getBeginLoc(), From->getType(), ToType)))
3358 ConstructorsOnly = true;
3360 if (!S.isCompleteType(From->getExprLoc(), ToType)) {
3361 // We're not going to find any constructors.
3362 } else if (CXXRecordDecl *ToRecordDecl
3363 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) {
3365 Expr **Args = &From;
3366 unsigned NumArgs = 1;
3367 bool ListInitializing = false;
3368 if (InitListExpr *InitList = dyn_cast<InitListExpr>(From)) {
3369 // But first, see if there is an init-list-constructor that will work.
3370 OverloadingResult Result = IsInitializerListConstructorConversion(
3371 S, From, ToType, ToRecordDecl, User, CandidateSet, AllowExplicit);
3372 if (Result != OR_No_Viable_Function)
3376 OverloadCandidateSet::CSK_InitByUserDefinedConversion);
3378 // If we're list-initializing, we pass the individual elements as
3379 // arguments, not the entire list.
3380 Args = InitList->getInits();
3381 NumArgs = InitList->getNumInits();
3382 ListInitializing = true;
3385 for (auto *D : S.LookupConstructors(ToRecordDecl)) {
3386 auto Info = getConstructorInfo(D);
3390 bool Usable = !Info.Constructor->isInvalidDecl();
3391 if (ListInitializing)
3392 Usable = Usable && (AllowExplicit || !Info.Constructor->isExplicit());
3395 Info.Constructor->isConvertingConstructor(AllowExplicit);
3397 bool SuppressUserConversions = !ConstructorsOnly;
3398 if (SuppressUserConversions && ListInitializing) {
3399 SuppressUserConversions = false;
3401 // If the first argument is (a reference to) the target type,
3402 // suppress conversions.
3403 SuppressUserConversions = isFirstArgumentCompatibleWithType(
3404 S.Context, Info.Constructor, ToType);
3407 if (Info.ConstructorTmpl)
3408 S.AddTemplateOverloadCandidate(
3409 Info.ConstructorTmpl, Info.FoundDecl,
3410 /*ExplicitArgs*/ nullptr, llvm::makeArrayRef(Args, NumArgs),
3411 CandidateSet, SuppressUserConversions,
3412 /*PartialOverloading*/ false, AllowExplicit);
3414 // Allow one user-defined conversion when user specifies a
3415 // From->ToType conversion via an static cast (c-style, etc).
3416 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
3417 llvm::makeArrayRef(Args, NumArgs),
3418 CandidateSet, SuppressUserConversions,
3419 /*PartialOverloading*/ false, AllowExplicit);
3425 // Enumerate conversion functions, if we're allowed to.
3426 if (ConstructorsOnly || isa<InitListExpr>(From)) {
3427 } else if (!S.isCompleteType(From->getBeginLoc(), From->getType())) {
3428 // No conversion functions from incomplete types.
3429 } else if (const RecordType *FromRecordType =
3430 From->getType()->getAs<RecordType>()) {
3431 if (CXXRecordDecl *FromRecordDecl
3432 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) {
3433 // Add all of the conversion functions as candidates.
3434 const auto &Conversions = FromRecordDecl->getVisibleConversionFunctions();
3435 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
3436 DeclAccessPair FoundDecl = I.getPair();
3437 NamedDecl *D = FoundDecl.getDecl();
3438 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext());
3439 if (isa<UsingShadowDecl>(D))
3440 D = cast<UsingShadowDecl>(D)->getTargetDecl();
3442 CXXConversionDecl *Conv;
3443 FunctionTemplateDecl *ConvTemplate;
3444 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D)))
3445 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
3447 Conv = cast<CXXConversionDecl>(D);
3449 if (AllowExplicit || !Conv->isExplicit()) {
3451 S.AddTemplateConversionCandidate(
3452 ConvTemplate, FoundDecl, ActingContext, From, ToType,
3453 CandidateSet, AllowObjCConversionOnExplicit, AllowExplicit);
3455 S.AddConversionCandidate(
3456 Conv, FoundDecl, ActingContext, From, ToType, CandidateSet,
3457 AllowObjCConversionOnExplicit, AllowExplicit);
3463 bool HadMultipleCandidates = (CandidateSet.size() > 1);
3465 OverloadCandidateSet::iterator Best;
3466 switch (auto Result =
3467 CandidateSet.BestViableFunction(S, From->getBeginLoc(), Best)) {
3470 // Record the standard conversion we used and the conversion function.
3471 if (CXXConstructorDecl *Constructor
3472 = dyn_cast<CXXConstructorDecl>(Best->Function)) {
3473 // C++ [over.ics.user]p1:
3474 // If the user-defined conversion is specified by a
3475 // constructor (12.3.1), the initial standard conversion
3476 // sequence converts the source type to the type required by
3477 // the argument of the constructor.
3479 QualType ThisType = Constructor->getThisType();
3480 if (isa<InitListExpr>(From)) {
3481 // Initializer lists don't have conversions as such.
3482 User.Before.setAsIdentityConversion();
3484 if (Best->Conversions[0].isEllipsis())
3485 User.EllipsisConversion = true;
3487 User.Before = Best->Conversions[0].Standard;
3488 User.EllipsisConversion = false;
3491 User.HadMultipleCandidates = HadMultipleCandidates;
3492 User.ConversionFunction = Constructor;
3493 User.FoundConversionFunction = Best->FoundDecl;
3494 User.After.setAsIdentityConversion();
3495 User.After.setFromType(ThisType->castAs<PointerType>()->getPointeeType());
3496 User.After.setAllToTypes(ToType);
3499 if (CXXConversionDecl *Conversion
3500 = dyn_cast<CXXConversionDecl>(Best->Function)) {
3501 // C++ [over.ics.user]p1:
3503 // [...] If the user-defined conversion is specified by a
3504 // conversion function (12.3.2), the initial standard
3505 // conversion sequence converts the source type to the
3506 // implicit object parameter of the conversion function.
3507 User.Before = Best->Conversions[0].Standard;
3508 User.HadMultipleCandidates = HadMultipleCandidates;
3509 User.ConversionFunction = Conversion;
3510 User.FoundConversionFunction = Best->FoundDecl;
3511 User.EllipsisConversion = false;
3513 // C++ [over.ics.user]p2:
3514 // The second standard conversion sequence converts the
3515 // result of the user-defined conversion to the target type
3516 // for the sequence. Since an implicit conversion sequence
3517 // is an initialization, the special rules for
3518 // initialization by user-defined conversion apply when
3519 // selecting the best user-defined conversion for a
3520 // user-defined conversion sequence (see 13.3.3 and
3522 User.After = Best->FinalConversion;
3525 llvm_unreachable("Not a constructor or conversion function?");
3527 case OR_No_Viable_Function:
3528 return OR_No_Viable_Function;
3531 return OR_Ambiguous;
3534 llvm_unreachable("Invalid OverloadResult!");
3538 Sema::DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType) {
3539 ImplicitConversionSequence ICS;
3540 OverloadCandidateSet CandidateSet(From->getExprLoc(),
3541 OverloadCandidateSet::CSK_Normal);
3542 OverloadingResult OvResult =
3543 IsUserDefinedConversion(*this, From, ToType, ICS.UserDefined,
3544 CandidateSet, false, false);
3546 if (!(OvResult == OR_Ambiguous ||
3547 (OvResult == OR_No_Viable_Function && !CandidateSet.empty())))
3550 auto Cands = CandidateSet.CompleteCandidates(*this, OCD_AllCandidates, From);
3551 if (OvResult == OR_Ambiguous)
3552 Diag(From->getBeginLoc(), diag::err_typecheck_ambiguous_condition)
3553 << From->getType() << ToType << From->getSourceRange();
3554 else { // OR_No_Viable_Function && !CandidateSet.empty()
3555 if (!RequireCompleteType(From->getBeginLoc(), ToType,
3556 diag::err_typecheck_nonviable_condition_incomplete,
3557 From->getType(), From->getSourceRange()))
3558 Diag(From->getBeginLoc(), diag::err_typecheck_nonviable_condition)
3559 << false << From->getType() << From->getSourceRange() << ToType;
3562 CandidateSet.NoteCandidates(
3563 *this, From, Cands);
3567 /// Compare the user-defined conversion functions or constructors
3568 /// of two user-defined conversion sequences to determine whether any ordering
3570 static ImplicitConversionSequence::CompareKind
3571 compareConversionFunctions(Sema &S, FunctionDecl *Function1,
3572 FunctionDecl *Function2) {
3573 if (!S.getLangOpts().ObjC || !S.getLangOpts().CPlusPlus11)
3574 return ImplicitConversionSequence::Indistinguishable;
3577 // If both conversion functions are implicitly-declared conversions from
3578 // a lambda closure type to a function pointer and a block pointer,
3579 // respectively, always prefer the conversion to a function pointer,
3580 // because the function pointer is more lightweight and is more likely
3581 // to keep code working.
3582 CXXConversionDecl *Conv1 = dyn_cast_or_null<CXXConversionDecl>(Function1);
3584 return ImplicitConversionSequence::Indistinguishable;
3586 CXXConversionDecl *Conv2 = dyn_cast<CXXConversionDecl>(Function2);
3588 return ImplicitConversionSequence::Indistinguishable;
3590 if (Conv1->getParent()->isLambda() && Conv2->getParent()->isLambda()) {
3591 bool Block1 = Conv1->getConversionType()->isBlockPointerType();
3592 bool Block2 = Conv2->getConversionType()->isBlockPointerType();
3593 if (Block1 != Block2)
3594 return Block1 ? ImplicitConversionSequence::Worse
3595 : ImplicitConversionSequence::Better;
3598 return ImplicitConversionSequence::Indistinguishable;
3601 static bool hasDeprecatedStringLiteralToCharPtrConversion(
3602 const ImplicitConversionSequence &ICS) {
3603 return (ICS.isStandard() && ICS.Standard.DeprecatedStringLiteralToCharPtr) ||
3604 (ICS.isUserDefined() &&
3605 ICS.UserDefined.Before.DeprecatedStringLiteralToCharPtr);
3608 /// CompareImplicitConversionSequences - Compare two implicit
3609 /// conversion sequences to determine whether one is better than the
3610 /// other or if they are indistinguishable (C++ 13.3.3.2).
3611 static ImplicitConversionSequence::CompareKind
3612 CompareImplicitConversionSequences(Sema &S, SourceLocation Loc,
3613 const ImplicitConversionSequence& ICS1,
3614 const ImplicitConversionSequence& ICS2)
3616 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit
3617 // conversion sequences (as defined in 13.3.3.1)
3618 // -- a standard conversion sequence (13.3.3.1.1) is a better
3619 // conversion sequence than a user-defined conversion sequence or
3620 // an ellipsis conversion sequence, and
3621 // -- a user-defined conversion sequence (13.3.3.1.2) is a better
3622 // conversion sequence than an ellipsis conversion sequence
3625 // C++0x [over.best.ics]p10:
3626 // For the purpose of ranking implicit conversion sequences as
3627 // described in 13.3.3.2, the ambiguous conversion sequence is
3628 // treated as a user-defined sequence that is indistinguishable
3629 // from any other user-defined conversion sequence.
3631 // String literal to 'char *' conversion has been deprecated in C++03. It has
3632 // been removed from C++11. We still accept this conversion, if it happens at
3633 // the best viable function. Otherwise, this conversion is considered worse
3634 // than ellipsis conversion. Consider this as an extension; this is not in the
3635 // standard. For example:
3637 // int &f(...); // #1
3638 // void f(char*); // #2
3639 // void g() { int &r = f("foo"); }
3641 // In C++03, we pick #2 as the best viable function.
3642 // In C++11, we pick #1 as the best viable function, because ellipsis
3643 // conversion is better than string-literal to char* conversion (since there
3644 // is no such conversion in C++11). If there was no #1 at all or #1 couldn't
3645 // convert arguments, #2 would be the best viable function in C++11.
3646 // If the best viable function has this conversion, a warning will be issued
3647 // in C++03, or an ExtWarn (+SFINAE failure) will be issued in C++11.
3649 if (S.getLangOpts().CPlusPlus11 && !S.getLangOpts().WritableStrings &&
3650 hasDeprecatedStringLiteralToCharPtrConversion(ICS1) !=
3651 hasDeprecatedStringLiteralToCharPtrConversion(ICS2))
3652 return hasDeprecatedStringLiteralToCharPtrConversion(ICS1)
3653 ? ImplicitConversionSequence::Worse
3654 : ImplicitConversionSequence::Better;
3656 if (ICS1.getKindRank() < ICS2.getKindRank())
3657 return ImplicitConversionSequence::Better;
3658 if (ICS2.getKindRank() < ICS1.getKindRank())
3659 return ImplicitConversionSequence::Worse;
3661 // The following checks require both conversion sequences to be of
3663 if (ICS1.getKind() != ICS2.getKind())
3664 return ImplicitConversionSequence::Indistinguishable;
3666 ImplicitConversionSequence::CompareKind Result =
3667 ImplicitConversionSequence::Indistinguishable;
3669 // Two implicit conversion sequences of the same form are
3670 // indistinguishable conversion sequences unless one of the
3671 // following rules apply: (C++ 13.3.3.2p3):
3673 // List-initialization sequence L1 is a better conversion sequence than
3674 // list-initialization sequence L2 if:
3675 // - L1 converts to std::initializer_list<X> for some X and L2 does not, or,
3677 // - L1 converts to type "array of N1 T", L2 converts to type "array of N2 T",
3678 // and N1 is smaller than N2.,
3679 // even if one of the other rules in this paragraph would otherwise apply.
3680 if (!ICS1.isBad()) {
3681 if (ICS1.isStdInitializerListElement() &&
3682 !ICS2.isStdInitializerListElement())
3683 return ImplicitConversionSequence::Better;
3684 if (!ICS1.isStdInitializerListElement() &&
3685 ICS2.isStdInitializerListElement())
3686 return ImplicitConversionSequence::Worse;
3689 if (ICS1.isStandard())
3690 // Standard conversion sequence S1 is a better conversion sequence than
3691 // standard conversion sequence S2 if [...]
3692 Result = CompareStandardConversionSequences(S, Loc,
3693 ICS1.Standard, ICS2.Standard);
3694 else if (ICS1.isUserDefined()) {
3695 // User-defined conversion sequence U1 is a better conversion
3696 // sequence than another user-defined conversion sequence U2 if
3697 // they contain the same user-defined conversion function or
3698 // constructor and if the second standard conversion sequence of
3699 // U1 is better than the second standard conversion sequence of
3700 // U2 (C++ 13.3.3.2p3).
3701 if (ICS1.UserDefined.ConversionFunction ==
3702 ICS2.UserDefined.ConversionFunction)
3703 Result = CompareStandardConversionSequences(S, Loc,
3704 ICS1.UserDefined.After,
3705 ICS2.UserDefined.After);
3707 Result = compareConversionFunctions(S,
3708 ICS1.UserDefined.ConversionFunction,
3709 ICS2.UserDefined.ConversionFunction);
3715 // Per 13.3.3.2p3, compare the given standard conversion sequences to
3716 // determine if one is a proper subset of the other.
3717 static ImplicitConversionSequence::CompareKind
3718 compareStandardConversionSubsets(ASTContext &Context,
3719 const StandardConversionSequence& SCS1,
3720 const StandardConversionSequence& SCS2) {
3721 ImplicitConversionSequence::CompareKind Result
3722 = ImplicitConversionSequence::Indistinguishable;
3724 // the identity conversion sequence is considered to be a subsequence of
3725 // any non-identity conversion sequence
3726 if (SCS1.isIdentityConversion() && !SCS2.isIdentityConversion())
3727 return ImplicitConversionSequence::Better;
3728 else if (!SCS1.isIdentityConversion() && SCS2.isIdentityConversion())
3729 return ImplicitConversionSequence::Worse;
3731 if (SCS1.Second != SCS2.Second) {
3732 if (SCS1.Second == ICK_Identity)
3733 Result = ImplicitConversionSequence::Better;
3734 else if (SCS2.Second == ICK_Identity)
3735 Result = ImplicitConversionSequence::Worse;
3737 return ImplicitConversionSequence::Indistinguishable;
3738 } else if (!Context.hasSimilarType(SCS1.getToType(1), SCS2.getToType(1)))
3739 return ImplicitConversionSequence::Indistinguishable;
3741 if (SCS1.Third == SCS2.Third) {
3742 return Context.hasSameType(SCS1.getToType(2), SCS2.getToType(2))? Result
3743 : ImplicitConversionSequence::Indistinguishable;
3746 if (SCS1.Third == ICK_Identity)
3747 return Result == ImplicitConversionSequence::Worse
3748 ? ImplicitConversionSequence::Indistinguishable
3749 : ImplicitConversionSequence::Better;
3751 if (SCS2.Third == ICK_Identity)
3752 return Result == ImplicitConversionSequence::Better
3753 ? ImplicitConversionSequence::Indistinguishable
3754 : ImplicitConversionSequence::Worse;
3756 return ImplicitConversionSequence::Indistinguishable;
3759 /// Determine whether one of the given reference bindings is better
3760 /// than the other based on what kind of bindings they are.
3762 isBetterReferenceBindingKind(const StandardConversionSequence &SCS1,
3763 const StandardConversionSequence &SCS2) {
3764 // C++0x [over.ics.rank]p3b4:
3765 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an
3766 // implicit object parameter of a non-static member function declared
3767 // without a ref-qualifier, and *either* S1 binds an rvalue reference
3768 // to an rvalue and S2 binds an lvalue reference *or S1 binds an
3769 // lvalue reference to a function lvalue and S2 binds an rvalue
3772 // FIXME: Rvalue references. We're going rogue with the above edits,
3773 // because the semantics in the current C++0x working paper (N3225 at the
3774 // time of this writing) break the standard definition of std::forward
3775 // and std::reference_wrapper when dealing with references to functions.
3776 // Proposed wording changes submitted to CWG for consideration.
3777 if (SCS1.BindsImplicitObjectArgumentWithoutRefQualifier ||
3778 SCS2.BindsImplicitObjectArgumentWithoutRefQualifier)
3781 return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue &&
3782 SCS2.IsLvalueReference) ||
3783 (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue &&
3784 !SCS2.IsLvalueReference && SCS2.BindsToFunctionLvalue);
3787 enum class FixedEnumPromotion {
3790 ToPromotedUnderlyingType
3793 /// Returns kind of fixed enum promotion the \a SCS uses.
3794 static FixedEnumPromotion
3795 getFixedEnumPromtion(Sema &S, const StandardConversionSequence &SCS) {
3797 if (SCS.Second != ICK_Integral_Promotion)
3798 return FixedEnumPromotion::None;
3800 QualType FromType = SCS.getFromType();
3801 if (!FromType->isEnumeralType())
3802 return FixedEnumPromotion::None;
3804 EnumDecl *Enum = FromType->getAs<EnumType>()->getDecl();
3805 if (!Enum->isFixed())
3806 return FixedEnumPromotion::None;
3808 QualType UnderlyingType = Enum->getIntegerType();
3809 if (S.Context.hasSameType(SCS.getToType(1), UnderlyingType))
3810 return FixedEnumPromotion::ToUnderlyingType;
3812 return FixedEnumPromotion::ToPromotedUnderlyingType;
3815 /// CompareStandardConversionSequences - Compare two standard
3816 /// conversion sequences to determine whether one is better than the
3817 /// other or if they are indistinguishable (C++ 13.3.3.2p3).
3818 static ImplicitConversionSequence::CompareKind
3819 CompareStandardConversionSequences(Sema &S, SourceLocation Loc,
3820 const StandardConversionSequence& SCS1,
3821 const StandardConversionSequence& SCS2)
3823 // Standard conversion sequence S1 is a better conversion sequence
3824 // than standard conversion sequence S2 if (C++ 13.3.3.2p3):
3826 // -- S1 is a proper subsequence of S2 (comparing the conversion
3827 // sequences in the canonical form defined by 13.3.3.1.1,
3828 // excluding any Lvalue Transformation; the identity conversion
3829 // sequence is considered to be a subsequence of any
3830 // non-identity conversion sequence) or, if not that,
3831 if (ImplicitConversionSequence::CompareKind CK
3832 = compareStandardConversionSubsets(S.Context, SCS1, SCS2))
3835 // -- the rank of S1 is better than the rank of S2 (by the rules
3836 // defined below), or, if not that,
3837 ImplicitConversionRank Rank1 = SCS1.getRank();
3838 ImplicitConversionRank Rank2 = SCS2.getRank();
3840 return ImplicitConversionSequence::Better;
3841 else if (Rank2 < Rank1)
3842 return ImplicitConversionSequence::Worse;
3844 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank
3845 // are indistinguishable unless one of the following rules
3848 // A conversion that is not a conversion of a pointer, or
3849 // pointer to member, to bool is better than another conversion
3850 // that is such a conversion.
3851 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool())
3852 return SCS2.isPointerConversionToBool()
3853 ? ImplicitConversionSequence::Better
3854 : ImplicitConversionSequence::Worse;
3856 // C++14 [over.ics.rank]p4b2:
3857 // This is retroactively applied to C++11 by CWG 1601.
3859 // A conversion that promotes an enumeration whose underlying type is fixed
3860 // to its underlying type is better than one that promotes to the promoted
3861 // underlying type, if the two are different.
3862 FixedEnumPromotion FEP1 = getFixedEnumPromtion(S, SCS1);
3863 FixedEnumPromotion FEP2 = getFixedEnumPromtion(S, SCS2);
3864 if (FEP1 != FixedEnumPromotion::None && FEP2 != FixedEnumPromotion::None &&
3866 return FEP1 == FixedEnumPromotion::ToUnderlyingType
3867 ? ImplicitConversionSequence::Better
3868 : ImplicitConversionSequence::Worse;
3870 // C++ [over.ics.rank]p4b2:
3872 // If class B is derived directly or indirectly from class A,
3873 // conversion of B* to A* is better than conversion of B* to
3874 // void*, and conversion of A* to void* is better than conversion
3876 bool SCS1ConvertsToVoid
3877 = SCS1.isPointerConversionToVoidPointer(S.Context);
3878 bool SCS2ConvertsToVoid
3879 = SCS2.isPointerConversionToVoidPointer(S.Context);
3880 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) {
3881 // Exactly one of the conversion sequences is a conversion to
3882 // a void pointer; it's the worse conversion.
3883 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better
3884 : ImplicitConversionSequence::Worse;
3885 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) {
3886 // Neither conversion sequence converts to a void pointer; compare
3887 // their derived-to-base conversions.
3888 if (ImplicitConversionSequence::CompareKind DerivedCK
3889 = CompareDerivedToBaseConversions(S, Loc, SCS1, SCS2))
3891 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid &&
3892 !S.Context.hasSameType(SCS1.getFromType(), SCS2.getFromType())) {
3893 // Both conversion sequences are conversions to void
3894 // pointers. Compare the source types to determine if there's an
3895 // inheritance relationship in their sources.
3896 QualType FromType1 = SCS1.getFromType();
3897 QualType FromType2 = SCS2.getFromType();
3899 // Adjust the types we're converting from via the array-to-pointer
3900 // conversion, if we need to.
3901 if (SCS1.First == ICK_Array_To_Pointer)
3902 FromType1 = S.Context.getArrayDecayedType(FromType1);
3903 if (SCS2.First == ICK_Array_To_Pointer)
3904 FromType2 = S.Context.getArrayDecayedType(FromType2);
3906 QualType FromPointee1 = FromType1->getPointeeType().getUnqualifiedType();
3907 QualType FromPointee2 = FromType2->getPointeeType().getUnqualifiedType();
3909 if (S.IsDerivedFrom(Loc, FromPointee2, FromPointee1))
3910 return ImplicitConversionSequence::Better;
3911 else if (S.IsDerivedFrom(Loc, FromPointee1, FromPointee2))
3912 return ImplicitConversionSequence::Worse;
3914 // Objective-C++: If one interface is more specific than the
3915 // other, it is the better one.
3916 const ObjCObjectPointerType* FromObjCPtr1
3917 = FromType1->getAs<ObjCObjectPointerType>();
3918 const ObjCObjectPointerType* FromObjCPtr2
3919 = FromType2->getAs<ObjCObjectPointerType>();
3920 if (FromObjCPtr1 && FromObjCPtr2) {
3921 bool AssignLeft = S.Context.canAssignObjCInterfaces(FromObjCPtr1,
3923 bool AssignRight = S.Context.canAssignObjCInterfaces(FromObjCPtr2,
3925 if (AssignLeft != AssignRight) {
3926 return AssignLeft? ImplicitConversionSequence::Better
3927 : ImplicitConversionSequence::Worse;
3932 // Compare based on qualification conversions (C++ 13.3.3.2p3,
3934 if (ImplicitConversionSequence::CompareKind QualCK
3935 = CompareQualificationConversions(S, SCS1, SCS2))
3938 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) {
3939 // Check for a better reference binding based on the kind of bindings.
3940 if (isBetterReferenceBindingKind(SCS1, SCS2))
3941 return ImplicitConversionSequence::Better;
3942 else if (isBetterReferenceBindingKind(SCS2, SCS1))
3943 return ImplicitConversionSequence::Worse;
3945 // C++ [over.ics.rank]p3b4:
3946 // -- S1 and S2 are reference bindings (8.5.3), and the types to
3947 // which the references refer are the same type except for
3948 // top-level cv-qualifiers, and the type to which the reference
3949 // initialized by S2 refers is more cv-qualified than the type
3950 // to which the reference initialized by S1 refers.
3951 QualType T1 = SCS1.getToType(2);
3952 QualType T2 = SCS2.getToType(2);
3953 T1 = S.Context.getCanonicalType(T1);
3954 T2 = S.Context.getCanonicalType(T2);
3955 Qualifiers T1Quals, T2Quals;
3956 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals);
3957 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals);
3958 if (UnqualT1 == UnqualT2) {
3959 // Objective-C++ ARC: If the references refer to objects with different
3960 // lifetimes, prefer bindings that don't change lifetime.
3961 if (SCS1.ObjCLifetimeConversionBinding !=
3962 SCS2.ObjCLifetimeConversionBinding) {
3963 return SCS1.ObjCLifetimeConversionBinding
3964 ? ImplicitConversionSequence::Worse
3965 : ImplicitConversionSequence::Better;
3968 // If the type is an array type, promote the element qualifiers to the
3969 // type for comparison.
3970 if (isa<ArrayType>(T1) && T1Quals)
3971 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals);
3972 if (isa<ArrayType>(T2) && T2Quals)
3973 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals);
3974 if (T2.isMoreQualifiedThan(T1))
3975 return ImplicitConversionSequence::Better;
3976 else if (T1.isMoreQualifiedThan(T2))
3977 return ImplicitConversionSequence::Worse;
3981 // In Microsoft mode, prefer an integral conversion to a
3982 // floating-to-integral conversion if the integral conversion
3983 // is between types of the same size.
3991 // Here, MSVC will call f(int) instead of generating a compile error
3992 // as clang will do in standard mode.
3993 if (S.getLangOpts().MSVCCompat && SCS1.Second == ICK_Integral_Conversion &&
3994 SCS2.Second == ICK_Floating_Integral &&
3995 S.Context.getTypeSize(SCS1.getFromType()) ==
3996 S.Context.getTypeSize(SCS1.getToType(2)))
3997 return ImplicitConversionSequence::Better;
3999 // Prefer a compatible vector conversion over a lax vector conversion
4002 // typedef float __v4sf __attribute__((__vector_size__(16)));
4003 // void f(vector float);
4004 // void f(vector signed int);
4009 // Here, we'd like to choose f(vector float) and not
4010 // report an ambiguous call error
4011 if (SCS1.Second == ICK_Vector_Conversion &&
4012 SCS2.Second == ICK_Vector_Conversion) {
4013 bool SCS1IsCompatibleVectorConversion = S.Context.areCompatibleVectorTypes(
4014 SCS1.getFromType(), SCS1.getToType(2));
4015 bool SCS2IsCompatibleVectorConversion = S.Context.areCompatibleVectorTypes(
4016 SCS2.getFromType(), SCS2.getToType(2));
4018 if (SCS1IsCompatibleVectorConversion != SCS2IsCompatibleVectorConversion)
4019 return SCS1IsCompatibleVectorConversion
4020 ? ImplicitConversionSequence::Better
4021 : ImplicitConversionSequence::Worse;
4024 return ImplicitConversionSequence::Indistinguishable;
4027 /// CompareQualificationConversions - Compares two standard conversion
4028 /// sequences to determine whether they can be ranked based on their
4029 /// qualification conversions (C++ 13.3.3.2p3 bullet 3).
4030 static ImplicitConversionSequence::CompareKind
4031 CompareQualificationConversions(Sema &S,
4032 const StandardConversionSequence& SCS1,
4033 const StandardConversionSequence& SCS2) {
4035 // -- S1 and S2 differ only in their qualification conversion and
4036 // yield similar types T1 and T2 (C++ 4.4), respectively, and the
4037 // cv-qualification signature of type T1 is a proper subset of
4038 // the cv-qualification signature of type T2, and S1 is not the
4039 // deprecated string literal array-to-pointer conversion (4.2).
4040 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second ||
4041 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification)
4042 return ImplicitConversionSequence::Indistinguishable;
4044 // FIXME: the example in the standard doesn't use a qualification
4046 QualType T1 = SCS1.getToType(2);
4047 QualType T2 = SCS2.getToType(2);
4048 T1 = S.Context.getCanonicalType(T1);
4049 T2 = S.Context.getCanonicalType(T2);
4050 Qualifiers T1Quals, T2Quals;
4051 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals);
4052 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals);
4054 // If the types are the same, we won't learn anything by unwrapped
4056 if (UnqualT1 == UnqualT2)
4057 return ImplicitConversionSequence::Indistinguishable;
4059 // If the type is an array type, promote the element qualifiers to the type
4061 if (isa<ArrayType>(T1) && T1Quals)
4062 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals);
4063 if (isa<ArrayType>(T2) && T2Quals)
4064 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals);
4066 ImplicitConversionSequence::CompareKind Result
4067 = ImplicitConversionSequence::Indistinguishable;
4069 // Objective-C++ ARC:
4070 // Prefer qualification conversions not involving a change in lifetime
4071 // to qualification conversions that do not change lifetime.
4072 if (SCS1.QualificationIncludesObjCLifetime !=
4073 SCS2.QualificationIncludesObjCLifetime) {
4074 Result = SCS1.QualificationIncludesObjCLifetime
4075 ? ImplicitConversionSequence::Worse
4076 : ImplicitConversionSequence::Better;
4079 while (S.Context.UnwrapSimilarTypes(T1, T2)) {
4080 // Within each iteration of the loop, we check the qualifiers to
4081 // determine if this still looks like a qualification
4082 // conversion. Then, if all is well, we unwrap one more level of
4083 // pointers or pointers-to-members and do it all again
4084 // until there are no more pointers or pointers-to-members left
4085 // to unwrap. This essentially mimics what
4086 // IsQualificationConversion does, but here we're checking for a
4087 // strict subset of qualifiers.
4088 if (T1.getQualifiers().withoutObjCLifetime() ==
4089 T2.getQualifiers().withoutObjCLifetime())
4090 // The qualifiers are the same, so this doesn't tell us anything
4091 // about how the sequences rank.
4092 // ObjC ownership quals are omitted above as they interfere with
4093 // the ARC overload rule.
4095 else if (T2.isMoreQualifiedThan(T1)) {
4096 // T1 has fewer qualifiers, so it could be the better sequence.
4097 if (Result == ImplicitConversionSequence::Worse)
4098 // Neither has qualifiers that are a subset of the other's
4100 return ImplicitConversionSequence::Indistinguishable;
4102 Result = ImplicitConversionSequence::Better;
4103 } else if (T1.isMoreQualifiedThan(T2)) {
4104 // T2 has fewer qualifiers, so it could be the better sequence.
4105 if (Result == ImplicitConversionSequence::Better)
4106 // Neither has qualifiers that are a subset of the other's
4108 return ImplicitConversionSequence::Indistinguishable;
4110 Result = ImplicitConversionSequence::Worse;
4112 // Qualifiers are disjoint.
4113 return ImplicitConversionSequence::Indistinguishable;
4116 // If the types after this point are equivalent, we're done.
4117 if (S.Context.hasSameUnqualifiedType(T1, T2))
4121 // Check that the winning standard conversion sequence isn't using
4122 // the deprecated string literal array to pointer conversion.
4124 case ImplicitConversionSequence::Better:
4125 if (SCS1.DeprecatedStringLiteralToCharPtr)
4126 Result = ImplicitConversionSequence::Indistinguishable;
4129 case ImplicitConversionSequence::Indistinguishable:
4132 case ImplicitConversionSequence::Worse:
4133 if (SCS2.DeprecatedStringLiteralToCharPtr)
4134 Result = ImplicitConversionSequence::Indistinguishable;
4141 /// CompareDerivedToBaseConversions - Compares two standard conversion
4142 /// sequences to determine whether they can be ranked based on their
4143 /// various kinds of derived-to-base conversions (C++
4144 /// [over.ics.rank]p4b3). As part of these checks, we also look at
4145 /// conversions between Objective-C interface types.
4146 static ImplicitConversionSequence::CompareKind
4147 CompareDerivedToBaseConversions(Sema &S, SourceLocation Loc,
4148 const StandardConversionSequence& SCS1,
4149 const StandardConversionSequence& SCS2) {
4150 QualType FromType1 = SCS1.getFromType();
4151 QualType ToType1 = SCS1.getToType(1);
4152 QualType FromType2 = SCS2.getFromType();
4153 QualType ToType2 = SCS2.getToType(1);
4155 // Adjust the types we're converting from via the array-to-pointer
4156 // conversion, if we need to.
4157 if (SCS1.First == ICK_Array_To_Pointer)
4158 FromType1 = S.Context.getArrayDecayedType(FromType1);
4159 if (SCS2.First == ICK_Array_To_Pointer)
4160 FromType2 = S.Context.getArrayDecayedType(FromType2);
4162 // Canonicalize all of the types.
4163 FromType1 = S.Context.getCanonicalType(FromType1);
4164 ToType1 = S.Context.getCanonicalType(ToType1);
4165 FromType2 = S.Context.getCanonicalType(FromType2);
4166 ToType2 = S.Context.getCanonicalType(ToType2);
4168 // C++ [over.ics.rank]p4b3:
4170 // If class B is derived directly or indirectly from class A and
4171 // class C is derived directly or indirectly from B,
4173 // Compare based on pointer conversions.
4174 if (SCS1.Second == ICK_Pointer_Conversion &&
4175 SCS2.Second == ICK_Pointer_Conversion &&
4176 /*FIXME: Remove if Objective-C id conversions get their own rank*/
4177 FromType1->isPointerType() && FromType2->isPointerType() &&
4178 ToType1->isPointerType() && ToType2->isPointerType()) {
4179 QualType FromPointee1 =
4180 FromType1->castAs<PointerType>()->getPointeeType().getUnqualifiedType();
4181 QualType ToPointee1 =
4182 ToType1->castAs<PointerType>()->getPointeeType().getUnqualifiedType();
4183 QualType FromPointee2 =
4184 FromType2->castAs<PointerType>()->getPointeeType().getUnqualifiedType();
4185 QualType ToPointee2 =
4186 ToType2->castAs<PointerType>()->getPointeeType().getUnqualifiedType();
4188 // -- conversion of C* to B* is better than conversion of C* to A*,
4189 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) {
4190 if (S.IsDerivedFrom(Loc, ToPointee1, ToPointee2))
4191 return ImplicitConversionSequence::Better;
4192 else if (S.IsDerivedFrom(Loc, ToPointee2, ToPointee1))
4193 return ImplicitConversionSequence::Worse;
4196 // -- conversion of B* to A* is better than conversion of C* to A*,
4197 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) {
4198 if (S.IsDerivedFrom(Loc, FromPointee2, FromPointee1))
4199 return ImplicitConversionSequence::Better;
4200 else if (S.IsDerivedFrom(Loc, FromPointee1, FromPointee2))
4201 return ImplicitConversionSequence::Worse;
4203 } else if (SCS1.Second == ICK_Pointer_Conversion &&
4204 SCS2.Second == ICK_Pointer_Conversion) {
4205 const ObjCObjectPointerType *FromPtr1
4206 = FromType1->getAs<ObjCObjectPointerType>();
4207 const ObjCObjectPointerType *FromPtr2
4208 = FromType2->getAs<ObjCObjectPointerType>();
4209 const ObjCObjectPointerType *ToPtr1
4210 = ToType1->getAs<ObjCObjectPointerType>();
4211 const ObjCObjectPointerType *ToPtr2
4212 = ToType2->getAs<ObjCObjectPointerType>();
4214 if (FromPtr1 && FromPtr2 && ToPtr1 && ToPtr2) {
4215 // Apply the same conversion ranking rules for Objective-C pointer types
4216 // that we do for C++ pointers to class types. However, we employ the
4217 // Objective-C pseudo-subtyping relationship used for assignment of
4218 // Objective-C pointer types.
4220 = S.Context.canAssignObjCInterfaces(FromPtr1, FromPtr2);
4221 bool FromAssignRight
4222 = S.Context.canAssignObjCInterfaces(FromPtr2, FromPtr1);
4224 = S.Context.canAssignObjCInterfaces(ToPtr1, ToPtr2);
4226 = S.Context.canAssignObjCInterfaces(ToPtr2, ToPtr1);
4228 // A conversion to an a non-id object pointer type or qualified 'id'
4229 // type is better than a conversion to 'id'.
4230 if (ToPtr1->isObjCIdType() &&
4231 (ToPtr2->isObjCQualifiedIdType() || ToPtr2->getInterfaceDecl()))
4232 return ImplicitConversionSequence::Worse;
4233 if (ToPtr2->isObjCIdType() &&
4234 (ToPtr1->isObjCQualifiedIdType() || ToPtr1->getInterfaceDecl()))
4235 return ImplicitConversionSequence::Better;
4237 // A conversion to a non-id object pointer type is better than a
4238 // conversion to a qualified 'id' type
4239 if (ToPtr1->isObjCQualifiedIdType() && ToPtr2->getInterfaceDecl())
4240 return ImplicitConversionSequence::Worse;
4241 if (ToPtr2->isObjCQualifiedIdType() && ToPtr1->getInterfaceDecl())
4242 return ImplicitConversionSequence::Better;
4244 // A conversion to an a non-Class object pointer type or qualified 'Class'
4245 // type is better than a conversion to 'Class'.
4246 if (ToPtr1->isObjCClassType() &&
4247 (ToPtr2->isObjCQualifiedClassType() || ToPtr2->getInterfaceDecl()))
4248 return ImplicitConversionSequence::Worse;
4249 if (ToPtr2->isObjCClassType() &&
4250 (ToPtr1->isObjCQualifiedClassType() || ToPtr1->getInterfaceDecl()))
4251 return ImplicitConversionSequence::Better;
4253 // A conversion to a non-Class object pointer type is better than a
4254 // conversion to a qualified 'Class' type.
4255 if (ToPtr1->isObjCQualifiedClassType() && ToPtr2->getInterfaceDecl())
4256 return ImplicitConversionSequence::Worse;
4257 if (ToPtr2->isObjCQualifiedClassType() && ToPtr1->getInterfaceDecl())
4258 return ImplicitConversionSequence::Better;
4260 // -- "conversion of C* to B* is better than conversion of C* to A*,"
4261 if (S.Context.hasSameType(FromType1, FromType2) &&
4262 !FromPtr1->isObjCIdType() && !FromPtr1->isObjCClassType() &&
4263 (ToAssignLeft != ToAssignRight)) {
4264 if (FromPtr1->isSpecialized()) {
4265 // "conversion of B<A> * to B * is better than conversion of B * to
4268 FromPtr1->getInterfaceDecl() == ToPtr1->getInterfaceDecl();
4270 FromPtr1->getInterfaceDecl() == ToPtr2->getInterfaceDecl();
4273 return ImplicitConversionSequence::Better;
4274 } else if (IsSecondSame)
4275 return ImplicitConversionSequence::Worse;
4277 return ToAssignLeft? ImplicitConversionSequence::Worse
4278 : ImplicitConversionSequence::Better;
4281 // -- "conversion of B* to A* is better than conversion of C* to A*,"
4282 if (S.Context.hasSameUnqualifiedType(ToType1, ToType2) &&
4283 (FromAssignLeft != FromAssignRight))
4284 return FromAssignLeft? ImplicitConversionSequence::Better
4285 : ImplicitConversionSequence::Worse;
4289 // Ranking of member-pointer types.
4290 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member &&
4291 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() &&
4292 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) {
4293 const MemberPointerType * FromMemPointer1 =
4294 FromType1->getAs<MemberPointerType>();
4295 const MemberPointerType * ToMemPointer1 =
4296 ToType1->getAs<MemberPointerType>();
4297 const MemberPointerType * FromMemPointer2 =
4298 FromType2->getAs<MemberPointerType>();
4299 const MemberPointerType * ToMemPointer2 =
4300 ToType2->getAs<MemberPointerType>();
4301 const Type *FromPointeeType1 = FromMemPointer1->getClass();
4302 const Type *ToPointeeType1 = ToMemPointer1->getClass();
4303 const Type *FromPointeeType2 = FromMemPointer2->getClass();
4304 const Type *ToPointeeType2 = ToMemPointer2->getClass();
4305 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType();
4306 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType();
4307 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType();
4308 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType();
4309 // conversion of A::* to B::* is better than conversion of A::* to C::*,
4310 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) {
4311 if (S.IsDerivedFrom(Loc, ToPointee1, ToPointee2))
4312 return ImplicitConversionSequence::Worse;
4313 else if (S.IsDerivedFrom(Loc, ToPointee2, ToPointee1))
4314 return ImplicitConversionSequence::Better;
4316 // conversion of B::* to C::* is better than conversion of A::* to C::*
4317 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) {
4318 if (S.IsDerivedFrom(Loc, FromPointee1, FromPointee2))
4319 return ImplicitConversionSequence::Better;
4320 else if (S.IsDerivedFrom(Loc, FromPointee2, FromPointee1))
4321 return ImplicitConversionSequence::Worse;
4325 if (SCS1.Second == ICK_Derived_To_Base) {
4326 // -- conversion of C to B is better than conversion of C to A,
4327 // -- binding of an expression of type C to a reference of type
4328 // B& is better than binding an expression of type C to a
4329 // reference of type A&,
4330 if (S.Context.hasSameUnqualifiedType(FromType1, FromType2) &&
4331 !S.Context.hasSameUnqualifiedType(ToType1, ToType2)) {
4332 if (S.IsDerivedFrom(Loc, ToType1, ToType2))
4333 return ImplicitConversionSequence::Better;
4334 else if (S.IsDerivedFrom(Loc, ToType2, ToType1))
4335 return ImplicitConversionSequence::Worse;
4338 // -- conversion of B to A is better than conversion of C to A.
4339 // -- binding of an expression of type B to a reference of type
4340 // A& is better than binding an expression of type C to a
4341 // reference of type A&,
4342 if (!S.Context.hasSameUnqualifiedType(FromType1, FromType2) &&
4343 S.Context.hasSameUnqualifiedType(ToType1, ToType2)) {
4344 if (S.IsDerivedFrom(Loc, FromType2, FromType1))
4345 return ImplicitConversionSequence::Better;
4346 else if (S.IsDerivedFrom(Loc, FromType1, FromType2))
4347 return ImplicitConversionSequence::Worse;
4351 return ImplicitConversionSequence::Indistinguishable;
4354 /// Determine whether the given type is valid, e.g., it is not an invalid
4356 static bool isTypeValid(QualType T) {
4357 if (CXXRecordDecl *Record = T->getAsCXXRecordDecl())
4358 return !Record->isInvalidDecl();
4363 /// CompareReferenceRelationship - Compare the two types T1 and T2 to
4364 /// determine whether they are reference-related,
4365 /// reference-compatible, reference-compatible with added
4366 /// qualification, or incompatible, for use in C++ initialization by
4367 /// reference (C++ [dcl.ref.init]p4). Neither type can be a reference
4368 /// type, and the first type (T1) is the pointee type of the reference
4369 /// type being initialized.
4370 Sema::ReferenceCompareResult
4371 Sema::CompareReferenceRelationship(SourceLocation Loc,
4372 QualType OrigT1, QualType OrigT2,
4373 bool &DerivedToBase,
4374 bool &ObjCConversion,
4375 bool &ObjCLifetimeConversion,
4376 bool &FunctionConversion) {
4377 assert(!OrigT1->isReferenceType() &&
4378 "T1 must be the pointee type of the reference type");
4379 assert(!OrigT2->isReferenceType() && "T2 cannot be a reference type");
4381 QualType T1 = Context.getCanonicalType(OrigT1);
4382 QualType T2 = Context.getCanonicalType(OrigT2);
4383 Qualifiers T1Quals, T2Quals;
4384 QualType UnqualT1 = Context.getUnqualifiedArrayType(T1, T1Quals);
4385 QualType UnqualT2 = Context.getUnqualifiedArrayType(T2, T2Quals);
4387 // C++ [dcl.init.ref]p4:
4388 // Given types "cv1 T1" and "cv2 T2," "cv1 T1" is
4389 // reference-related to "cv2 T2" if T1 is the same type as T2, or
4390 // T1 is a base class of T2.
4391 DerivedToBase = false;
4392 ObjCConversion = false;
4393 ObjCLifetimeConversion = false;
4394 QualType ConvertedT2;
4395 if (UnqualT1 == UnqualT2) {
4397 } else if (isCompleteType(Loc, OrigT2) &&
4398 isTypeValid(UnqualT1) && isTypeValid(UnqualT2) &&
4399 IsDerivedFrom(Loc, UnqualT2, UnqualT1))
4400 DerivedToBase = true;
4401 else if (UnqualT1->isObjCObjectOrInterfaceType() &&
4402 UnqualT2->isObjCObjectOrInterfaceType() &&
4403 Context.canBindObjCObjectType(UnqualT1, UnqualT2))
4404 ObjCConversion = true;
4405 else if (UnqualT2->isFunctionType() &&
4406 IsFunctionConversion(UnqualT2, UnqualT1, ConvertedT2)) {
4407 // C++1z [dcl.init.ref]p4:
4408 // cv1 T1" is reference-compatible with "cv2 T2" if [...] T2 is "noexcept
4409 // function" and T1 is "function"
4411 // We extend this to also apply to 'noreturn', so allow any function
4412 // conversion between function types.
4413 FunctionConversion = true;
4414 return Ref_Compatible;
4416 return Ref_Incompatible;
4418 // At this point, we know that T1 and T2 are reference-related (at
4421 // If the type is an array type, promote the element qualifiers to the type
4423 if (isa<ArrayType>(T1) && T1Quals)
4424 T1 = Context.getQualifiedType(UnqualT1, T1Quals);
4425 if (isa<ArrayType>(T2) && T2Quals)
4426 T2 = Context.getQualifiedType(UnqualT2, T2Quals);
4428 // C++ [dcl.init.ref]p4:
4429 // "cv1 T1" is reference-compatible with "cv2 T2" if T1 is
4430 // reference-related to T2 and cv1 is the same cv-qualification
4431 // as, or greater cv-qualification than, cv2. For purposes of
4432 // overload resolution, cases for which cv1 is greater
4433 // cv-qualification than cv2 are identified as
4434 // reference-compatible with added qualification (see 13.3.3.2).
4436 // Note that we also require equivalence of Objective-C GC and address-space
4437 // qualifiers when performing these computations, so that e.g., an int in
4438 // address space 1 is not reference-compatible with an int in address
4440 if (T1Quals.getObjCLifetime() != T2Quals.getObjCLifetime() &&
4441 T1Quals.compatiblyIncludesObjCLifetime(T2Quals)) {
4442 if (isNonTrivialObjCLifetimeConversion(T2Quals, T1Quals))
4443 ObjCLifetimeConversion = true;
4445 T1Quals.removeObjCLifetime();
4446 T2Quals.removeObjCLifetime();
4449 // MS compiler ignores __unaligned qualifier for references; do the same.
4450 T1Quals.removeUnaligned();
4451 T2Quals.removeUnaligned();
4453 if (T1Quals.compatiblyIncludes(T2Quals))
4454 return Ref_Compatible;
4459 /// Look for a user-defined conversion to a value reference-compatible
4460 /// with DeclType. Return true if something definite is found.
4462 FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS,
4463 QualType DeclType, SourceLocation DeclLoc,
4464 Expr *Init, QualType T2, bool AllowRvalues,
4465 bool AllowExplicit) {
4466 assert(T2->isRecordType() && "Can only find conversions of record types.");
4467 CXXRecordDecl *T2RecordDecl
4468 = dyn_cast<CXXRecordDecl>(T2->castAs<RecordType>()->getDecl());
4470 OverloadCandidateSet CandidateSet(
4471 DeclLoc, OverloadCandidateSet::CSK_InitByUserDefinedConversion);
4472 const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
4473 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4475 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4476 if (isa<UsingShadowDecl>(D))
4477 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4479 FunctionTemplateDecl *ConvTemplate
4480 = dyn_cast<FunctionTemplateDecl>(D);
4481 CXXConversionDecl *Conv;
4483 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4485 Conv = cast<CXXConversionDecl>(D);
4487 // If this is an explicit conversion, and we're not allowed to consider
4488 // explicit conversions, skip it.
4489 if (!AllowExplicit && Conv->isExplicit())
4493 bool DerivedToBase = false;
4494 bool ObjCConversion = false;
4495 bool ObjCLifetimeConversion = false;
4496 bool FunctionConversion = false;
4498 // If we are initializing an rvalue reference, don't permit conversion
4499 // functions that return lvalues.
4500 if (!ConvTemplate && DeclType->isRValueReferenceType()) {
4501 const ReferenceType *RefType
4502 = Conv->getConversionType()->getAs<LValueReferenceType>();
4503 if (RefType && !RefType->getPointeeType()->isFunctionType())
4507 if (!ConvTemplate &&
4508 S.CompareReferenceRelationship(
4510 Conv->getConversionType()
4511 .getNonReferenceType()
4512 .getUnqualifiedType(),
4513 DeclType.getNonReferenceType().getUnqualifiedType(),
4514 DerivedToBase, ObjCConversion, ObjCLifetimeConversion,
4515 FunctionConversion) == Sema::Ref_Incompatible)
4518 // If the conversion function doesn't return a reference type,
4519 // it can't be considered for this conversion. An rvalue reference
4520 // is only acceptable if its referencee is a function type.
4522 const ReferenceType *RefType =
4523 Conv->getConversionType()->getAs<ReferenceType>();
4525 (!RefType->isLValueReferenceType() &&
4526 !RefType->getPointeeType()->isFunctionType()))
4531 S.AddTemplateConversionCandidate(
4532 ConvTemplate, I.getPair(), ActingDC, Init, DeclType, CandidateSet,
4533 /*AllowObjCConversionOnExplicit=*/false, AllowExplicit);
4535 S.AddConversionCandidate(
4536 Conv, I.getPair(), ActingDC, Init, DeclType, CandidateSet,
4537 /*AllowObjCConversionOnExplicit=*/false, AllowExplicit);
4540 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4542 OverloadCandidateSet::iterator Best;
4543 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best)) {
4545 // C++ [over.ics.ref]p1:
4547 // [...] If the parameter binds directly to the result of
4548 // applying a conversion function to the argument
4549 // expression, the implicit conversion sequence is a
4550 // user-defined conversion sequence (13.3.3.1.2), with the
4551 // second standard conversion sequence either an identity
4552 // conversion or, if the conversion function returns an
4553 // entity of a type that is a derived class of the parameter
4554 // type, a derived-to-base Conversion.
4555 if (!Best->FinalConversion.DirectBinding)
4558 ICS.setUserDefined();
4559 ICS.UserDefined.Before = Best->Conversions[0].Standard;
4560 ICS.UserDefined.After = Best->FinalConversion;
4561 ICS.UserDefined.HadMultipleCandidates = HadMultipleCandidates;
4562 ICS.UserDefined.ConversionFunction = Best->Function;
4563 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl;
4564 ICS.UserDefined.EllipsisConversion = false;
4565 assert(ICS.UserDefined.After.ReferenceBinding &&
4566 ICS.UserDefined.After.DirectBinding &&
4567 "Expected a direct reference binding!");
4572 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin();
4573 Cand != CandidateSet.end(); ++Cand)
4575 ICS.Ambiguous.addConversion(Cand->FoundDecl, Cand->Function);
4578 case OR_No_Viable_Function:
4580 // There was no suitable conversion, or we found a deleted
4581 // conversion; continue with other checks.
4585 llvm_unreachable("Invalid OverloadResult!");
4588 /// Compute an implicit conversion sequence for reference
4590 static ImplicitConversionSequence
4591 TryReferenceInit(Sema &S, Expr *Init, QualType DeclType,
4592 SourceLocation DeclLoc,
4593 bool SuppressUserConversions,
4594 bool AllowExplicit) {
4595 assert(DeclType->isReferenceType() && "Reference init needs a reference");
4597 // Most paths end in a failed conversion.
4598 ImplicitConversionSequence ICS;
4599 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType);
4601 QualType T1 = DeclType->castAs<ReferenceType>()->getPointeeType();
4602 QualType T2 = Init->getType();
4604 // If the initializer is the address of an overloaded function, try
4605 // to resolve the overloaded function. If all goes well, T2 is the
4606 // type of the resulting function.
4607 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) {
4608 DeclAccessPair Found;
4609 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType,
4614 // Compute some basic properties of the types and the initializer.
4615 bool isRValRef = DeclType->isRValueReferenceType();
4616 bool DerivedToBase = false;
4617 bool ObjCConversion = false;
4618 bool ObjCLifetimeConversion = false;
4619 bool FunctionConversion = false;
4620 Expr::Classification InitCategory = Init->Classify(S.Context);
4621 Sema::ReferenceCompareResult RefRelationship = S.CompareReferenceRelationship(
4622 DeclLoc, T1, T2, DerivedToBase, ObjCConversion, ObjCLifetimeConversion,
4623 FunctionConversion);
4625 // C++0x [dcl.init.ref]p5:
4626 // A reference to type "cv1 T1" is initialized by an expression
4627 // of type "cv2 T2" as follows:
4629 // -- If reference is an lvalue reference and the initializer expression
4631 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is
4632 // reference-compatible with "cv2 T2," or
4634 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here.
4635 if (InitCategory.isLValue() && RefRelationship == Sema::Ref_Compatible) {
4636 // C++ [over.ics.ref]p1:
4637 // When a parameter of reference type binds directly (8.5.3)
4638 // to an argument expression, the implicit conversion sequence
4639 // is the identity conversion, unless the argument expression
4640 // has a type that is a derived class of the parameter type,
4641 // in which case the implicit conversion sequence is a
4642 // derived-to-base Conversion (13.3.3.1).
4644 ICS.Standard.First = ICK_Identity;
4645 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base
4646 : ObjCConversion? ICK_Compatible_Conversion
4648 ICS.Standard.Third = ICK_Identity;
4649 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr();
4650 ICS.Standard.setToType(0, T2);
4651 ICS.Standard.setToType(1, T1);
4652 ICS.Standard.setToType(2, T1);
4653 ICS.Standard.ReferenceBinding = true;
4654 ICS.Standard.DirectBinding = true;
4655 ICS.Standard.IsLvalueReference = !isRValRef;
4656 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType();
4657 ICS.Standard.BindsToRvalue = false;
4658 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4659 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion;
4660 ICS.Standard.CopyConstructor = nullptr;
4661 ICS.Standard.DeprecatedStringLiteralToCharPtr = false;
4663 // Nothing more to do: the inaccessibility/ambiguity check for
4664 // derived-to-base conversions is suppressed when we're
4665 // computing the implicit conversion sequence (C++
4666 // [over.best.ics]p2).
4670 // -- has a class type (i.e., T2 is a class type), where T1 is
4671 // not reference-related to T2, and can be implicitly
4672 // converted to an lvalue of type "cv3 T3," where "cv1 T1"
4673 // is reference-compatible with "cv3 T3" 92) (this
4674 // conversion is selected by enumerating the applicable
4675 // conversion functions (13.3.1.6) and choosing the best
4676 // one through overload resolution (13.3)),
4677 if (!SuppressUserConversions && T2->isRecordType() &&
4678 S.isCompleteType(DeclLoc, T2) &&
4679 RefRelationship == Sema::Ref_Incompatible) {
4680 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc,
4681 Init, T2, /*AllowRvalues=*/false,
4687 // -- Otherwise, the reference shall be an lvalue reference to a
4688 // non-volatile const type (i.e., cv1 shall be const), or the reference
4689 // shall be an rvalue reference.
4690 if (!isRValRef && (!T1.isConstQualified() || T1.isVolatileQualified()))
4693 // -- If the initializer expression
4695 // -- is an xvalue, class prvalue, array prvalue or function
4696 // lvalue and "cv1 T1" is reference-compatible with "cv2 T2", or
4697 if (RefRelationship == Sema::Ref_Compatible &&
4698 (InitCategory.isXValue() ||
4699 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) ||
4700 (InitCategory.isLValue() && T2->isFunctionType()))) {
4702 ICS.Standard.First = ICK_Identity;
4703 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base
4704 : ObjCConversion? ICK_Compatible_Conversion
4706 ICS.Standard.Third = ICK_Identity;
4707 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr();
4708 ICS.Standard.setToType(0, T2);
4709 ICS.Standard.setToType(1, T1);
4710 ICS.Standard.setToType(2, T1);
4711 ICS.Standard.ReferenceBinding = true;
4712 // In C++0x, this is always a direct binding. In C++98/03, it's a direct
4713 // binding unless we're binding to a class prvalue.
4714 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we
4715 // allow the use of rvalue references in C++98/03 for the benefit of
4716 // standard library implementors; therefore, we need the xvalue check here.
4717 ICS.Standard.DirectBinding =
4718 S.getLangOpts().CPlusPlus11 ||
4719 !(InitCategory.isPRValue() || T2->isRecordType());
4720 ICS.Standard.IsLvalueReference = !isRValRef;
4721 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType();
4722 ICS.Standard.BindsToRvalue = InitCategory.isRValue();
4723 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4724 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion;
4725 ICS.Standard.CopyConstructor = nullptr;
4726 ICS.Standard.DeprecatedStringLiteralToCharPtr = false;
4730 // -- has a class type (i.e., T2 is a class type), where T1 is not
4731 // reference-related to T2, and can be implicitly converted to
4732 // an xvalue, class prvalue, or function lvalue of type
4733 // "cv3 T3", where "cv1 T1" is reference-compatible with
4736 // then the reference is bound to the value of the initializer
4737 // expression in the first case and to the result of the conversion
4738 // in the second case (or, in either case, to an appropriate base
4739 // class subobject).
4740 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible &&
4741 T2->isRecordType() && S.isCompleteType(DeclLoc, T2) &&
4742 FindConversionForRefInit(S, ICS, DeclType, DeclLoc,
4743 Init, T2, /*AllowRvalues=*/true,
4745 // In the second case, if the reference is an rvalue reference
4746 // and the second standard conversion sequence of the
4747 // user-defined conversion sequence includes an lvalue-to-rvalue
4748 // conversion, the program is ill-formed.
4749 if (ICS.isUserDefined() && isRValRef &&
4750 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue)
4751 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType);
4756 // A temporary of function type cannot be created; don't even try.
4757 if (T1->isFunctionType())
4760 // -- Otherwise, a temporary of type "cv1 T1" is created and
4761 // initialized from the initializer expression using the
4762 // rules for a non-reference copy initialization (8.5). The
4763 // reference is then bound to the temporary. If T1 is
4764 // reference-related to T2, cv1 must be the same
4765 // cv-qualification as, or greater cv-qualification than,
4766 // cv2; otherwise, the program is ill-formed.
4767 if (RefRelationship == Sema::Ref_Related) {
4768 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then
4769 // we would be reference-compatible or reference-compatible with
4770 // added qualification. But that wasn't the case, so the reference
4771 // initialization fails.
4773 // Note that we only want to check address spaces and cvr-qualifiers here.
4774 // ObjC GC, lifetime and unaligned qualifiers aren't important.
4775 Qualifiers T1Quals = T1.getQualifiers();
4776 Qualifiers T2Quals = T2.getQualifiers();
4777 T1Quals.removeObjCGCAttr();
4778 T1Quals.removeObjCLifetime();
4779 T2Quals.removeObjCGCAttr();
4780 T2Quals.removeObjCLifetime();
4781 // MS compiler ignores __unaligned qualifier for references; do the same.
4782 T1Quals.removeUnaligned();
4783 T2Quals.removeUnaligned();
4784 if (!T1Quals.compatiblyIncludes(T2Quals))
4788 // If at least one of the types is a class type, the types are not
4789 // related, and we aren't allowed any user conversions, the
4790 // reference binding fails. This case is important for breaking
4791 // recursion, since TryImplicitConversion below will attempt to
4792 // create a temporary through the use of a copy constructor.
4793 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible &&
4794 (T1->isRecordType() || T2->isRecordType()))
4797 // If T1 is reference-related to T2 and the reference is an rvalue
4798 // reference, the initializer expression shall not be an lvalue.
4799 if (RefRelationship >= Sema::Ref_Related &&
4800 isRValRef && Init->Classify(S.Context).isLValue())
4803 // C++ [over.ics.ref]p2:
4804 // When a parameter of reference type is not bound directly to
4805 // an argument expression, the conversion sequence is the one
4806 // required to convert the argument expression to the
4807 // underlying type of the reference according to
4808 // 13.3.3.1. Conceptually, this conversion sequence corresponds
4809 // to copy-initializing a temporary of the underlying type with
4810 // the argument expression. Any difference in top-level
4811 // cv-qualification is subsumed by the initialization itself
4812 // and does not constitute a conversion.
4813 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions,
4814 /*AllowExplicit=*/false,
4815 /*InOverloadResolution=*/false,
4817 /*AllowObjCWritebackConversion=*/false,
4818 /*AllowObjCConversionOnExplicit=*/false);
4820 // Of course, that's still a reference binding.
4821 if (ICS.isStandard()) {
4822 ICS.Standard.ReferenceBinding = true;
4823 ICS.Standard.IsLvalueReference = !isRValRef;
4824 ICS.Standard.BindsToFunctionLvalue = false;
4825 ICS.Standard.BindsToRvalue = true;
4826 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4827 ICS.Standard.ObjCLifetimeConversionBinding = false;
4828 } else if (ICS.isUserDefined()) {
4829 const ReferenceType *LValRefType =
4830 ICS.UserDefined.ConversionFunction->getReturnType()
4831 ->getAs<LValueReferenceType>();
4833 // C++ [over.ics.ref]p3:
4834 // Except for an implicit object parameter, for which see 13.3.1, a
4835 // standard conversion sequence cannot be formed if it requires [...]
4836 // binding an rvalue reference to an lvalue other than a function
4838 // Note that the function case is not possible here.
4839 if (DeclType->isRValueReferenceType() && LValRefType) {
4840 // FIXME: This is the wrong BadConversionSequence. The problem is binding
4841 // an rvalue reference to a (non-function) lvalue, not binding an lvalue
4842 // reference to an rvalue!
4843 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, Init, DeclType);
4847 ICS.UserDefined.After.ReferenceBinding = true;
4848 ICS.UserDefined.After.IsLvalueReference = !isRValRef;
4849 ICS.UserDefined.After.BindsToFunctionLvalue = false;
4850 ICS.UserDefined.After.BindsToRvalue = !LValRefType;
4851 ICS.UserDefined.After.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4852 ICS.UserDefined.After.ObjCLifetimeConversionBinding = false;
4858 static ImplicitConversionSequence
4859 TryCopyInitialization(Sema &S, Expr *From, QualType ToType,
4860 bool SuppressUserConversions,
4861 bool InOverloadResolution,
4862 bool AllowObjCWritebackConversion,
4863 bool AllowExplicit = false);
4865 /// TryListConversion - Try to copy-initialize a value of type ToType from the
4866 /// initializer list From.
4867 static ImplicitConversionSequence
4868 TryListConversion(Sema &S, InitListExpr *From, QualType ToType,
4869 bool SuppressUserConversions,
4870 bool InOverloadResolution,
4871 bool AllowObjCWritebackConversion) {
4872 // C++11 [over.ics.list]p1:
4873 // When an argument is an initializer list, it is not an expression and
4874 // special rules apply for converting it to a parameter type.
4876 ImplicitConversionSequence Result;
4877 Result.setBad(BadConversionSequence::no_conversion, From, ToType);
4879 // We need a complete type for what follows. Incomplete types can never be
4880 // initialized from init lists.
4881 if (!S.isCompleteType(From->getBeginLoc(), ToType))
4885 // If the parameter type is a class X and the initializer list has a single
4886 // element of type cv U, where U is X or a class derived from X, the
4887 // implicit conversion sequence is the one required to convert the element
4888 // to the parameter type.
4890 // Otherwise, if the parameter type is a character array [... ]
4891 // and the initializer list has a single element that is an
4892 // appropriately-typed string literal (8.5.2 [dcl.init.string]), the
4893 // implicit conversion sequence is the identity conversion.
4894 if (From->getNumInits() == 1) {
4895 if (ToType->isRecordType()) {
4896 QualType InitType = From->getInit(0)->getType();
4897 if (S.Context.hasSameUnqualifiedType(InitType, ToType) ||
4898 S.IsDerivedFrom(From->getBeginLoc(), InitType, ToType))
4899 return TryCopyInitialization(S, From->getInit(0), ToType,
4900 SuppressUserConversions,
4901 InOverloadResolution,
4902 AllowObjCWritebackConversion);
4904 // FIXME: Check the other conditions here: array of character type,
4905 // initializer is a string literal.
4906 if (ToType->isArrayType()) {
4907 InitializedEntity Entity =
4908 InitializedEntity::InitializeParameter(S.Context, ToType,
4909 /*Consumed=*/false);
4910 if (S.CanPerformCopyInitialization(Entity, From)) {
4911 Result.setStandard();
4912 Result.Standard.setAsIdentityConversion();
4913 Result.Standard.setFromType(ToType);
4914 Result.Standard.setAllToTypes(ToType);
4920 // C++14 [over.ics.list]p2: Otherwise, if the parameter type [...] (below).
4921 // C++11 [over.ics.list]p2:
4922 // If the parameter type is std::initializer_list<X> or "array of X" and
4923 // all the elements can be implicitly converted to X, the implicit
4924 // conversion sequence is the worst conversion necessary to convert an
4925 // element of the list to X.
4927 // C++14 [over.ics.list]p3:
4928 // Otherwise, if the parameter type is "array of N X", if the initializer
4929 // list has exactly N elements or if it has fewer than N elements and X is
4930 // default-constructible, and if all the elements of the initializer list
4931 // can be implicitly converted to X, the implicit conversion sequence is
4932 // the worst conversion necessary to convert an element of the list to X.
4934 // FIXME: We're missing a lot of these checks.
4935 bool toStdInitializerList = false;
4937 if (ToType->isArrayType())
4938 X = S.Context.getAsArrayType(ToType)->getElementType();
4940 toStdInitializerList = S.isStdInitializerList(ToType, &X);
4942 for (unsigned i = 0, e = From->getNumInits(); i < e; ++i) {
4943 Expr *Init = From->getInit(i);
4944 ImplicitConversionSequence ICS =
4945 TryCopyInitialization(S, Init, X, SuppressUserConversions,
4946 InOverloadResolution,
4947 AllowObjCWritebackConversion);
4948 // If a single element isn't convertible, fail.
4953 // Otherwise, look for the worst conversion.
4954 if (Result.isBad() || CompareImplicitConversionSequences(
4955 S, From->getBeginLoc(), ICS, Result) ==
4956 ImplicitConversionSequence::Worse)
4960 // For an empty list, we won't have computed any conversion sequence.
4961 // Introduce the identity conversion sequence.
4962 if (From->getNumInits() == 0) {
4963 Result.setStandard();
4964 Result.Standard.setAsIdentityConversion();
4965 Result.Standard.setFromType(ToType);
4966 Result.Standard.setAllToTypes(ToType);
4969 Result.setStdInitializerListElement(toStdInitializerList);
4973 // C++14 [over.ics.list]p4:
4974 // C++11 [over.ics.list]p3:
4975 // Otherwise, if the parameter is a non-aggregate class X and overload
4976 // resolution chooses a single best constructor [...] the implicit
4977 // conversion sequence is a user-defined conversion sequence. If multiple
4978 // constructors are viable but none is better than the others, the
4979 // implicit conversion sequence is a user-defined conversion sequence.
4980 if (ToType->isRecordType() && !ToType->isAggregateType()) {
4981 // This function can deal with initializer lists.
4982 return TryUserDefinedConversion(S, From, ToType, SuppressUserConversions,
4983 /*AllowExplicit=*/false,
4984 InOverloadResolution, /*CStyle=*/false,
4985 AllowObjCWritebackConversion,
4986 /*AllowObjCConversionOnExplicit=*/false);
4989 // C++14 [over.ics.list]p5:
4990 // C++11 [over.ics.list]p4:
4991 // Otherwise, if the parameter has an aggregate type which can be
4992 // initialized from the initializer list [...] the implicit conversion
4993 // sequence is a user-defined conversion sequence.
4994 if (ToType->isAggregateType()) {
4995 // Type is an aggregate, argument is an init list. At this point it comes
4996 // down to checking whether the initialization works.
4997 // FIXME: Find out whether this parameter is consumed or not.
4998 InitializedEntity Entity =
4999 InitializedEntity::InitializeParameter(S.Context, ToType,
5000 /*Consumed=*/false);
5001 if (S.CanPerformAggregateInitializationForOverloadResolution(Entity,
5003 Result.setUserDefined();
5004 Result.UserDefined.Before.setAsIdentityConversion();
5005 // Initializer lists don't have a type.
5006 Result.UserDefined.Before.setFromType(QualType());
5007 Result.UserDefined.Before.setAllToTypes(QualType());
5009 Result.UserDefined.After.setAsIdentityConversion();
5010 Result.UserDefined.After.setFromType(ToType);
5011 Result.UserDefined.After.setAllToTypes(ToType);
5012 Result.UserDefined.ConversionFunction = nullptr;
5017 // C++14 [over.ics.list]p6:
5018 // C++11 [over.ics.list]p5:
5019 // Otherwise, if the parameter is a reference, see 13.3.3.1.4.
5020 if (ToType->isReferenceType()) {
5021 // The standard is notoriously unclear here, since 13.3.3.1.4 doesn't
5022 // mention initializer lists in any way. So we go by what list-
5023 // initialization would do and try to extrapolate from that.
5025 QualType T1 = ToType->castAs<ReferenceType>()->getPointeeType();
5027 // If the initializer list has a single element that is reference-related
5028 // to the parameter type, we initialize the reference from that.
5029 if (From->getNumInits() == 1) {
5030 Expr *Init = From->getInit(0);
5032 QualType T2 = Init->getType();
5034 // If the initializer is the address of an overloaded function, try
5035 // to resolve the overloaded function. If all goes well, T2 is the
5036 // type of the resulting function.
5037 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) {
5038 DeclAccessPair Found;
5039 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(
5040 Init, ToType, false, Found))
5044 // Compute some basic properties of the types and the initializer.
5045 bool dummy1 = false;
5046 bool dummy2 = false;
5047 bool dummy3 = false;
5048 bool dummy4 = false;
5049 Sema::ReferenceCompareResult RefRelationship =
5050 S.CompareReferenceRelationship(From->getBeginLoc(), T1, T2, dummy1,
5051 dummy2, dummy3, dummy4);
5053 if (RefRelationship >= Sema::Ref_Related) {
5054 return TryReferenceInit(S, Init, ToType, /*FIXME*/ From->getBeginLoc(),
5055 SuppressUserConversions,
5056 /*AllowExplicit=*/false);
5060 // Otherwise, we bind the reference to a temporary created from the
5061 // initializer list.
5062 Result = TryListConversion(S, From, T1, SuppressUserConversions,
5063 InOverloadResolution,
5064 AllowObjCWritebackConversion);
5065 if (Result.isFailure())
5067 assert(!Result.isEllipsis() &&
5068 "Sub-initialization cannot result in ellipsis conversion.");
5070 // Can we even bind to a temporary?
5071 if (ToType->isRValueReferenceType() ||
5072 (T1.isConstQualified() && !T1.isVolatileQualified())) {
5073 StandardConversionSequence &SCS = Result.isStandard() ? Result.Standard :
5074 Result.UserDefined.After;
5075 SCS.ReferenceBinding = true;
5076 SCS.IsLvalueReference = ToType->isLValueReferenceType();
5077 SCS.BindsToRvalue = true;
5078 SCS.BindsToFunctionLvalue = false;
5079 SCS.BindsImplicitObjectArgumentWithoutRefQualifier = false;
5080 SCS.ObjCLifetimeConversionBinding = false;
5082 Result.setBad(BadConversionSequence::lvalue_ref_to_rvalue,
5087 // C++14 [over.ics.list]p7:
5088 // C++11 [over.ics.list]p6:
5089 // Otherwise, if the parameter type is not a class:
5090 if (!ToType->isRecordType()) {
5091 // - if the initializer list has one element that is not itself an
5092 // initializer list, the implicit conversion sequence is the one
5093 // required to convert the element to the parameter type.
5094 unsigned NumInits = From->getNumInits();
5095 if (NumInits == 1 && !isa<InitListExpr>(From->getInit(0)))
5096 Result = TryCopyInitialization(S, From->getInit(0), ToType,
5097 SuppressUserConversions,
5098 InOverloadResolution,
5099 AllowObjCWritebackConversion);
5100 // - if the initializer list has no elements, the implicit conversion
5101 // sequence is the identity conversion.
5102 else if (NumInits == 0) {
5103 Result.setStandard();
5104 Result.Standard.setAsIdentityConversion();
5105 Result.Standard.setFromType(ToType);
5106 Result.Standard.setAllToTypes(ToType);
5111 // C++14 [over.ics.list]p8:
5112 // C++11 [over.ics.list]p7:
5113 // In all cases other than those enumerated above, no conversion is possible
5117 /// TryCopyInitialization - Try to copy-initialize a value of type
5118 /// ToType from the expression From. Return the implicit conversion
5119 /// sequence required to pass this argument, which may be a bad
5120 /// conversion sequence (meaning that the argument cannot be passed to
5121 /// a parameter of this type). If @p SuppressUserConversions, then we
5122 /// do not permit any user-defined conversion sequences.
5123 static ImplicitConversionSequence
5124 TryCopyInitialization(Sema &S, Expr *From, QualType ToType,
5125 bool SuppressUserConversions,
5126 bool InOverloadResolution,
5127 bool AllowObjCWritebackConversion,
5128 bool AllowExplicit) {
5129 if (InitListExpr *FromInitList = dyn_cast<InitListExpr>(From))
5130 return TryListConversion(S, FromInitList, ToType, SuppressUserConversions,
5131 InOverloadResolution,AllowObjCWritebackConversion);
5133 if (ToType->isReferenceType())
5134 return TryReferenceInit(S, From, ToType,
5135 /*FIXME:*/ From->getBeginLoc(),
5136 SuppressUserConversions, AllowExplicit);
5138 return TryImplicitConversion(S, From, ToType,
5139 SuppressUserConversions,
5140 /*AllowExplicit=*/false,
5141 InOverloadResolution,
5143 AllowObjCWritebackConversion,
5144 /*AllowObjCConversionOnExplicit=*/false);
5147 static bool TryCopyInitialization(const CanQualType FromQTy,
5148 const CanQualType ToQTy,
5151 ExprValueKind FromVK) {
5152 OpaqueValueExpr TmpExpr(Loc, FromQTy, FromVK);
5153 ImplicitConversionSequence ICS =
5154 TryCopyInitialization(S, &TmpExpr, ToQTy, true, true, false);
5156 return !ICS.isBad();
5159 /// TryObjectArgumentInitialization - Try to initialize the object
5160 /// parameter of the given member function (@c Method) from the
5161 /// expression @p From.
5162 static ImplicitConversionSequence
5163 TryObjectArgumentInitialization(Sema &S, SourceLocation Loc, QualType FromType,
5164 Expr::Classification FromClassification,
5165 CXXMethodDecl *Method,
5166 CXXRecordDecl *ActingContext) {
5167 QualType ClassType = S.Context.getTypeDeclType(ActingContext);
5168 // [class.dtor]p2: A destructor can be invoked for a const, volatile or
5169 // const volatile object.
5170 Qualifiers Quals = Method->getMethodQualifiers();
5171 if (isa<CXXDestructorDecl>(Method)) {
5173 Quals.addVolatile();
5176 QualType ImplicitParamType = S.Context.getQualifiedType(ClassType, Quals);
5178 // Set up the conversion sequence as a "bad" conversion, to allow us
5180 ImplicitConversionSequence ICS;
5182 // We need to have an object of class type.
5183 if (const PointerType *PT = FromType->getAs<PointerType>()) {
5184 FromType = PT->getPointeeType();
5186 // When we had a pointer, it's implicitly dereferenced, so we
5187 // better have an lvalue.
5188 assert(FromClassification.isLValue());
5191 assert(FromType->isRecordType());
5193 // C++0x [over.match.funcs]p4:
5194 // For non-static member functions, the type of the implicit object
5197 // - "lvalue reference to cv X" for functions declared without a
5198 // ref-qualifier or with the & ref-qualifier
5199 // - "rvalue reference to cv X" for functions declared with the &&
5202 // where X is the class of which the function is a member and cv is the
5203 // cv-qualification on the member function declaration.
5205 // However, when finding an implicit conversion sequence for the argument, we
5206 // are not allowed to perform user-defined conversions
5207 // (C++ [over.match.funcs]p5). We perform a simplified version of
5208 // reference binding here, that allows class rvalues to bind to
5209 // non-constant references.
5211 // First check the qualifiers.
5212 QualType FromTypeCanon = S.Context.getCanonicalType(FromType);
5213 if (ImplicitParamType.getCVRQualifiers()
5214 != FromTypeCanon.getLocalCVRQualifiers() &&
5215 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) {
5216 ICS.setBad(BadConversionSequence::bad_qualifiers,
5217 FromType, ImplicitParamType);
5221 if (FromTypeCanon.getQualifiers().hasAddressSpace()) {
5222 Qualifiers QualsImplicitParamType = ImplicitParamType.getQualifiers();
5223 Qualifiers QualsFromType = FromTypeCanon.getQualifiers();
5224 if (!QualsImplicitParamType.isAddressSpaceSupersetOf(QualsFromType)) {
5225 ICS.setBad(BadConversionSequence::bad_qualifiers,
5226 FromType, ImplicitParamType);
5231 // Check that we have either the same type or a derived type. It
5232 // affects the conversion rank.
5233 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType);
5234 ImplicitConversionKind SecondKind;
5235 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) {
5236 SecondKind = ICK_Identity;
5237 } else if (S.IsDerivedFrom(Loc, FromType, ClassType))
5238 SecondKind = ICK_Derived_To_Base;
5240 ICS.setBad(BadConversionSequence::unrelated_class,
5241 FromType, ImplicitParamType);
5245 // Check the ref-qualifier.
5246 switch (Method->getRefQualifier()) {
5248 // Do nothing; we don't care about lvalueness or rvalueness.
5252 if (!FromClassification.isLValue() && !Quals.hasOnlyConst()) {
5253 // non-const lvalue reference cannot bind to an rvalue
5254 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType,
5261 if (!FromClassification.isRValue()) {
5262 // rvalue reference cannot bind to an lvalue
5263 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType,
5270 // Success. Mark this as a reference binding.
5272 ICS.Standard.setAsIdentityConversion();
5273 ICS.Standard.Second = SecondKind;
5274 ICS.Standard.setFromType(FromType);
5275 ICS.Standard.setAllToTypes(ImplicitParamType);
5276 ICS.Standard.ReferenceBinding = true;
5277 ICS.Standard.DirectBinding = true;
5278 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue;
5279 ICS.Standard.BindsToFunctionLvalue = false;
5280 ICS.Standard.BindsToRvalue = FromClassification.isRValue();
5281 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier
5282 = (Method->getRefQualifier() == RQ_None);
5286 /// PerformObjectArgumentInitialization - Perform initialization of
5287 /// the implicit object parameter for the given Method with the given
5290 Sema::PerformObjectArgumentInitialization(Expr *From,
5291 NestedNameSpecifier *Qualifier,
5292 NamedDecl *FoundDecl,
5293 CXXMethodDecl *Method) {
5294 QualType FromRecordType, DestType;
5295 QualType ImplicitParamRecordType =
5296 Method->getThisType()->castAs<PointerType>()->getPointeeType();
5298 Expr::Classification FromClassification;
5299 if (const PointerType *PT = From->getType()->getAs<PointerType>()) {
5300 FromRecordType = PT->getPointeeType();
5301 DestType = Method->getThisType();
5302 FromClassification = Expr::Classification::makeSimpleLValue();
5304 FromRecordType = From->getType();
5305 DestType = ImplicitParamRecordType;
5306 FromClassification = From->Classify(Context);
5308 // When performing member access on an rvalue, materialize a temporary.
5309 if (From->isRValue()) {
5310 From = CreateMaterializeTemporaryExpr(FromRecordType, From,
5311 Method->getRefQualifier() !=
5312 RefQualifierKind::RQ_RValue);
5316 // Note that we always use the true parent context when performing
5317 // the actual argument initialization.
5318 ImplicitConversionSequence ICS = TryObjectArgumentInitialization(
5319 *this, From->getBeginLoc(), From->getType(), FromClassification, Method,
5320 Method->getParent());
5322 switch (ICS.Bad.Kind) {
5323 case BadConversionSequence::bad_qualifiers: {
5324 Qualifiers FromQs = FromRecordType.getQualifiers();
5325 Qualifiers ToQs = DestType.getQualifiers();
5326 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers();
5328 Diag(From->getBeginLoc(), diag::err_member_function_call_bad_cvr)
5329 << Method->getDeclName() << FromRecordType << (CVR - 1)
5330 << From->getSourceRange();
5331 Diag(Method->getLocation(), diag::note_previous_decl)
5332 << Method->getDeclName();
5338 case BadConversionSequence::lvalue_ref_to_rvalue:
5339 case BadConversionSequence::rvalue_ref_to_lvalue: {
5340 bool IsRValueQualified =
5341 Method->getRefQualifier() == RefQualifierKind::RQ_RValue;
5342 Diag(From->getBeginLoc(), diag::err_member_function_call_bad_ref)
5343 << Method->getDeclName() << FromClassification.isRValue()
5344 << IsRValueQualified;
5345 Diag(Method->getLocation(), diag::note_previous_decl)
5346 << Method->getDeclName();
5350 case BadConversionSequence::no_conversion:
5351 case BadConversionSequence::unrelated_class:
5355 return Diag(From->getBeginLoc(), diag::err_member_function_call_bad_type)
5356 << ImplicitParamRecordType << FromRecordType
5357 << From->getSourceRange();
5360 if (ICS.Standard.Second == ICK_Derived_To_Base) {
5361 ExprResult FromRes =
5362 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method);
5363 if (FromRes.isInvalid())
5365 From = FromRes.get();
5368 if (!Context.hasSameType(From->getType(), DestType)) {
5370 if (FromRecordType.getAddressSpace() != DestType.getAddressSpace())
5371 CK = CK_AddressSpaceConversion;
5374 From = ImpCastExprToType(From, DestType, CK, From->getValueKind()).get();
5379 /// TryContextuallyConvertToBool - Attempt to contextually convert the
5380 /// expression From to bool (C++0x [conv]p3).
5381 static ImplicitConversionSequence
5382 TryContextuallyConvertToBool(Sema &S, Expr *From) {
5383 return TryImplicitConversion(S, From, S.Context.BoolTy,
5384 /*SuppressUserConversions=*/false,
5385 /*AllowExplicit=*/true,
5386 /*InOverloadResolution=*/false,
5388 /*AllowObjCWritebackConversion=*/false,
5389 /*AllowObjCConversionOnExplicit=*/false);
5392 /// PerformContextuallyConvertToBool - Perform a contextual conversion
5393 /// of the expression From to bool (C++0x [conv]p3).
5394 ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) {
5395 if (checkPlaceholderForOverload(*this, From))
5398 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From);
5400 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting);
5402 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy))
5403 return Diag(From->getBeginLoc(), diag::err_typecheck_bool_condition)
5404 << From->getType() << From->getSourceRange();
5408 /// Check that the specified conversion is permitted in a converted constant
5409 /// expression, according to C++11 [expr.const]p3. Return true if the conversion
5411 static bool CheckConvertedConstantConversions(Sema &S,
5412 StandardConversionSequence &SCS) {
5413 // Since we know that the target type is an integral or unscoped enumeration
5414 // type, most conversion kinds are impossible. All possible First and Third
5415 // conversions are fine.
5416 switch (SCS.Second) {
5418 case ICK_Function_Conversion:
5419 case ICK_Integral_Promotion:
5420 case ICK_Integral_Conversion: // Narrowing conversions are checked elsewhere.
5421 case ICK_Zero_Queue_Conversion:
5424 case ICK_Boolean_Conversion:
5425 // Conversion from an integral or unscoped enumeration type to bool is
5426 // classified as ICK_Boolean_Conversion, but it's also arguably an integral
5427 // conversion, so we allow it in a converted constant expression.
5429 // FIXME: Per core issue 1407, we should not allow this, but that breaks
5430 // a lot of popular code. We should at least add a warning for this
5431 // (non-conforming) extension.
5432 return SCS.getFromType()->isIntegralOrUnscopedEnumerationType() &&
5433 SCS.getToType(2)->isBooleanType();
5435 case ICK_Pointer_Conversion:
5436 case ICK_Pointer_Member:
5437 // C++1z: null pointer conversions and null member pointer conversions are
5438 // only permitted if the source type is std::nullptr_t.
5439 return SCS.getFromType()->isNullPtrType();
5441 case ICK_Floating_Promotion:
5442 case ICK_Complex_Promotion:
5443 case ICK_Floating_Conversion:
5444 case ICK_Complex_Conversion:
5445 case ICK_Floating_Integral:
5446 case ICK_Compatible_Conversion:
5447 case ICK_Derived_To_Base:
5448 case ICK_Vector_Conversion:
5449 case ICK_Vector_Splat:
5450 case ICK_Complex_Real:
5451 case ICK_Block_Pointer_Conversion:
5452 case ICK_TransparentUnionConversion:
5453 case ICK_Writeback_Conversion:
5454 case ICK_Zero_Event_Conversion:
5455 case ICK_C_Only_Conversion:
5456 case ICK_Incompatible_Pointer_Conversion:
5459 case ICK_Lvalue_To_Rvalue:
5460 case ICK_Array_To_Pointer:
5461 case ICK_Function_To_Pointer:
5462 llvm_unreachable("found a first conversion kind in Second");
5464 case ICK_Qualification:
5465 llvm_unreachable("found a third conversion kind in Second");
5467 case ICK_Num_Conversion_Kinds:
5471 llvm_unreachable("unknown conversion kind");
5474 /// CheckConvertedConstantExpression - Check that the expression From is a
5475 /// converted constant expression of type T, perform the conversion and produce
5476 /// the converted expression, per C++11 [expr.const]p3.
5477 static ExprResult CheckConvertedConstantExpression(Sema &S, Expr *From,
5478 QualType T, APValue &Value,
5481 assert(S.getLangOpts().CPlusPlus11 &&
5482 "converted constant expression outside C++11");
5484 if (checkPlaceholderForOverload(S, From))
5487 // C++1z [expr.const]p3:
5488 // A converted constant expression of type T is an expression,
5489 // implicitly converted to type T, where the converted
5490 // expression is a constant expression and the implicit conversion
5491 // sequence contains only [... list of conversions ...].
5492 // C++1z [stmt.if]p2:
5493 // If the if statement is of the form if constexpr, the value of the
5494 // condition shall be a contextually converted constant expression of type
5496 ImplicitConversionSequence ICS =
5497 CCE == Sema::CCEK_ConstexprIf || CCE == Sema::CCEK_ExplicitBool
5498 ? TryContextuallyConvertToBool(S, From)
5499 : TryCopyInitialization(S, From, T,
5500 /*SuppressUserConversions=*/false,
5501 /*InOverloadResolution=*/false,
5502 /*AllowObjCWritebackConversion=*/false,
5503 /*AllowExplicit=*/false);
5504 StandardConversionSequence *SCS = nullptr;
5505 switch (ICS.getKind()) {
5506 case ImplicitConversionSequence::StandardConversion:
5507 SCS = &ICS.Standard;
5509 case ImplicitConversionSequence::UserDefinedConversion:
5510 // We are converting to a non-class type, so the Before sequence
5512 SCS = &ICS.UserDefined.After;
5514 case ImplicitConversionSequence::AmbiguousConversion:
5515 case ImplicitConversionSequence::BadConversion:
5516 if (!S.DiagnoseMultipleUserDefinedConversion(From, T))
5517 return S.Diag(From->getBeginLoc(),
5518 diag::err_typecheck_converted_constant_expression)
5519 << From->getType() << From->getSourceRange() << T;
5522 case ImplicitConversionSequence::EllipsisConversion:
5523 llvm_unreachable("ellipsis conversion in converted constant expression");
5526 // Check that we would only use permitted conversions.
5527 if (!CheckConvertedConstantConversions(S, *SCS)) {
5528 return S.Diag(From->getBeginLoc(),
5529 diag::err_typecheck_converted_constant_expression_disallowed)
5530 << From->getType() << From->getSourceRange() << T;
5532 // [...] and where the reference binding (if any) binds directly.
5533 if (SCS->ReferenceBinding && !SCS->DirectBinding) {
5534 return S.Diag(From->getBeginLoc(),
5535 diag::err_typecheck_converted_constant_expression_indirect)
5536 << From->getType() << From->getSourceRange() << T;
5540 S.PerformImplicitConversion(From, T, ICS, Sema::AA_Converting);
5541 if (Result.isInvalid())
5544 // C++2a [intro.execution]p5:
5545 // A full-expression is [...] a constant-expression [...]
5547 S.ActOnFinishFullExpr(Result.get(), From->getExprLoc(),
5548 /*DiscardedValue=*/false, /*IsConstexpr=*/true);
5549 if (Result.isInvalid())
5552 // Check for a narrowing implicit conversion.
5553 APValue PreNarrowingValue;
5554 QualType PreNarrowingType;
5555 switch (SCS->getNarrowingKind(S.Context, Result.get(), PreNarrowingValue,
5556 PreNarrowingType)) {
5557 case NK_Dependent_Narrowing:
5558 // Implicit conversion to a narrower type, but the expression is
5559 // value-dependent so we can't tell whether it's actually narrowing.
5560 case NK_Variable_Narrowing:
5561 // Implicit conversion to a narrower type, and the value is not a constant
5562 // expression. We'll diagnose this in a moment.
5563 case NK_Not_Narrowing:
5566 case NK_Constant_Narrowing:
5567 S.Diag(From->getBeginLoc(), diag::ext_cce_narrowing)
5568 << CCE << /*Constant*/ 1
5569 << PreNarrowingValue.getAsString(S.Context, PreNarrowingType) << T;
5572 case NK_Type_Narrowing:
5573 S.Diag(From->getBeginLoc(), diag::ext_cce_narrowing)
5574 << CCE << /*Constant*/ 0 << From->getType() << T;
5578 if (Result.get()->isValueDependent()) {
5583 // Check the expression is a constant expression.
5584 SmallVector<PartialDiagnosticAt, 8> Notes;
5585 Expr::EvalResult Eval;
5587 Expr::ConstExprUsage Usage = CCE == Sema::CCEK_TemplateArg
5588 ? Expr::EvaluateForMangling
5589 : Expr::EvaluateForCodeGen;
5591 if (!Result.get()->EvaluateAsConstantExpr(Eval, Usage, S.Context) ||
5592 (RequireInt && !Eval.Val.isInt())) {
5593 // The expression can't be folded, so we can't keep it at this position in
5595 Result = ExprError();
5599 if (Notes.empty()) {
5600 // It's a constant expression.
5601 return ConstantExpr::Create(S.Context, Result.get(), Value);
5605 // It's not a constant expression. Produce an appropriate diagnostic.
5606 if (Notes.size() == 1 &&
5607 Notes[0].second.getDiagID() == diag::note_invalid_subexpr_in_const_expr)
5608 S.Diag(Notes[0].first, diag::err_expr_not_cce) << CCE;
5610 S.Diag(From->getBeginLoc(), diag::err_expr_not_cce)
5611 << CCE << From->getSourceRange();
5612 for (unsigned I = 0; I < Notes.size(); ++I)
5613 S.Diag(Notes[I].first, Notes[I].second);
5618 ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
5619 APValue &Value, CCEKind CCE) {
5620 return ::CheckConvertedConstantExpression(*this, From, T, Value, CCE, false);
5623 ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
5624 llvm::APSInt &Value,
5626 assert(T->isIntegralOrEnumerationType() && "unexpected converted const type");
5629 auto R = ::CheckConvertedConstantExpression(*this, From, T, V, CCE, true);
5630 if (!R.isInvalid() && !R.get()->isValueDependent())
5636 /// dropPointerConversions - If the given standard conversion sequence
5637 /// involves any pointer conversions, remove them. This may change
5638 /// the result type of the conversion sequence.
5639 static void dropPointerConversion(StandardConversionSequence &SCS) {
5640 if (SCS.Second == ICK_Pointer_Conversion) {
5641 SCS.Second = ICK_Identity;
5642 SCS.Third = ICK_Identity;
5643 SCS.ToTypePtrs[2] = SCS.ToTypePtrs[1] = SCS.ToTypePtrs[0];
5647 /// TryContextuallyConvertToObjCPointer - Attempt to contextually
5648 /// convert the expression From to an Objective-C pointer type.
5649 static ImplicitConversionSequence
5650 TryContextuallyConvertToObjCPointer(Sema &S, Expr *From) {
5651 // Do an implicit conversion to 'id'.
5652 QualType Ty = S.Context.getObjCIdType();
5653 ImplicitConversionSequence ICS
5654 = TryImplicitConversion(S, From, Ty,
5655 // FIXME: Are these flags correct?
5656 /*SuppressUserConversions=*/false,
5657 /*AllowExplicit=*/true,
5658 /*InOverloadResolution=*/false,
5660 /*AllowObjCWritebackConversion=*/false,
5661 /*AllowObjCConversionOnExplicit=*/true);
5663 // Strip off any final conversions to 'id'.
5664 switch (ICS.getKind()) {
5665 case ImplicitConversionSequence::BadConversion:
5666 case ImplicitConversionSequence::AmbiguousConversion:
5667 case ImplicitConversionSequence::EllipsisConversion:
5670 case ImplicitConversionSequence::UserDefinedConversion:
5671 dropPointerConversion(ICS.UserDefined.After);
5674 case ImplicitConversionSequence::StandardConversion:
5675 dropPointerConversion(ICS.Standard);
5682 /// PerformContextuallyConvertToObjCPointer - Perform a contextual
5683 /// conversion of the expression From to an Objective-C pointer type.
5684 /// Returns a valid but null ExprResult if no conversion sequence exists.
5685 ExprResult Sema::PerformContextuallyConvertToObjCPointer(Expr *From) {
5686 if (checkPlaceholderForOverload(*this, From))
5689 QualType Ty = Context.getObjCIdType();
5690 ImplicitConversionSequence ICS =
5691 TryContextuallyConvertToObjCPointer(*this, From);
5693 return PerformImplicitConversion(From, Ty, ICS, AA_Converting);
5694 return ExprResult();
5697 /// Determine whether the provided type is an integral type, or an enumeration
5698 /// type of a permitted flavor.
5699 bool Sema::ICEConvertDiagnoser::match(QualType T) {
5700 return AllowScopedEnumerations ? T->isIntegralOrEnumerationType()
5701 : T->isIntegralOrUnscopedEnumerationType();
5705 diagnoseAmbiguousConversion(Sema &SemaRef, SourceLocation Loc, Expr *From,
5706 Sema::ContextualImplicitConverter &Converter,
5707 QualType T, UnresolvedSetImpl &ViableConversions) {
5709 if (Converter.Suppress)
5712 Converter.diagnoseAmbiguous(SemaRef, Loc, T) << From->getSourceRange();
5713 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) {
5714 CXXConversionDecl *Conv =
5715 cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl());
5716 QualType ConvTy = Conv->getConversionType().getNonReferenceType();
5717 Converter.noteAmbiguous(SemaRef, Conv, ConvTy);
5723 diagnoseNoViableConversion(Sema &SemaRef, SourceLocation Loc, Expr *&From,
5724 Sema::ContextualImplicitConverter &Converter,
5725 QualType T, bool HadMultipleCandidates,
5726 UnresolvedSetImpl &ExplicitConversions) {
5727 if (ExplicitConversions.size() == 1 && !Converter.Suppress) {
5728 DeclAccessPair Found = ExplicitConversions[0];
5729 CXXConversionDecl *Conversion =
5730 cast<CXXConversionDecl>(Found->getUnderlyingDecl());
5732 // The user probably meant to invoke the given explicit
5733 // conversion; use it.
5734 QualType ConvTy = Conversion->getConversionType().getNonReferenceType();
5735 std::string TypeStr;
5736 ConvTy.getAsStringInternal(TypeStr, SemaRef.getPrintingPolicy());
5738 Converter.diagnoseExplicitConv(SemaRef, Loc, T, ConvTy)
5739 << FixItHint::CreateInsertion(From->getBeginLoc(),
5740 "static_cast<" + TypeStr + ">(")
5741 << FixItHint::CreateInsertion(
5742 SemaRef.getLocForEndOfToken(From->getEndLoc()), ")");
5743 Converter.noteExplicitConv(SemaRef, Conversion, ConvTy);
5745 // If we aren't in a SFINAE context, build a call to the
5746 // explicit conversion function.
5747 if (SemaRef.isSFINAEContext())
5750 SemaRef.CheckMemberOperatorAccess(From->getExprLoc(), From, nullptr, Found);
5751 ExprResult Result = SemaRef.BuildCXXMemberCallExpr(From, Found, Conversion,
5752 HadMultipleCandidates);
5753 if (Result.isInvalid())
5755 // Record usage of conversion in an implicit cast.
5756 From = ImplicitCastExpr::Create(SemaRef.Context, Result.get()->getType(),
5757 CK_UserDefinedConversion, Result.get(),
5758 nullptr, Result.get()->getValueKind());
5763 static bool recordConversion(Sema &SemaRef, SourceLocation Loc, Expr *&From,
5764 Sema::ContextualImplicitConverter &Converter,
5765 QualType T, bool HadMultipleCandidates,
5766 DeclAccessPair &Found) {
5767 CXXConversionDecl *Conversion =
5768 cast<CXXConversionDecl>(Found->getUnderlyingDecl());
5769 SemaRef.CheckMemberOperatorAccess(From->getExprLoc(), From, nullptr, Found);
5771 QualType ToType = Conversion->getConversionType().getNonReferenceType();
5772 if (!Converter.SuppressConversion) {
5773 if (SemaRef.isSFINAEContext())
5776 Converter.diagnoseConversion(SemaRef, Loc, T, ToType)
5777 << From->getSourceRange();
5780 ExprResult Result = SemaRef.BuildCXXMemberCallExpr(From, Found, Conversion,
5781 HadMultipleCandidates);
5782 if (Result.isInvalid())
5784 // Record usage of conversion in an implicit cast.
5785 From = ImplicitCastExpr::Create(SemaRef.Context, Result.get()->getType(),
5786 CK_UserDefinedConversion, Result.get(),
5787 nullptr, Result.get()->getValueKind());
5791 static ExprResult finishContextualImplicitConversion(
5792 Sema &SemaRef, SourceLocation Loc, Expr *From,
5793 Sema::ContextualImplicitConverter &Converter) {
5794 if (!Converter.match(From->getType()) && !Converter.Suppress)
5795 Converter.diagnoseNoMatch(SemaRef, Loc, From->getType())
5796 << From->getSourceRange();
5798 return SemaRef.DefaultLvalueConversion(From);
5802 collectViableConversionCandidates(Sema &SemaRef, Expr *From, QualType ToType,
5803 UnresolvedSetImpl &ViableConversions,
5804 OverloadCandidateSet &CandidateSet) {
5805 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) {
5806 DeclAccessPair FoundDecl = ViableConversions[I];
5807 NamedDecl *D = FoundDecl.getDecl();
5808 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext());
5809 if (isa<UsingShadowDecl>(D))
5810 D = cast<UsingShadowDecl>(D)->getTargetDecl();
5812 CXXConversionDecl *Conv;
5813 FunctionTemplateDecl *ConvTemplate;
5814 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D)))
5815 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
5817 Conv = cast<CXXConversionDecl>(D);
5820 SemaRef.AddTemplateConversionCandidate(
5821 ConvTemplate, FoundDecl, ActingContext, From, ToType, CandidateSet,
5822 /*AllowObjCConversionOnExplicit=*/false, /*AllowExplicit*/ true);
5824 SemaRef.AddConversionCandidate(Conv, FoundDecl, ActingContext, From,
5825 ToType, CandidateSet,
5826 /*AllowObjCConversionOnExplicit=*/false,
5827 /*AllowExplicit*/ true);
5831 /// Attempt to convert the given expression to a type which is accepted
5832 /// by the given converter.
5834 /// This routine will attempt to convert an expression of class type to a
5835 /// type accepted by the specified converter. In C++11 and before, the class
5836 /// must have a single non-explicit conversion function converting to a matching
5837 /// type. In C++1y, there can be multiple such conversion functions, but only
5838 /// one target type.
5840 /// \param Loc The source location of the construct that requires the
5843 /// \param From The expression we're converting from.
5845 /// \param Converter Used to control and diagnose the conversion process.
5847 /// \returns The expression, converted to an integral or enumeration type if
5849 ExprResult Sema::PerformContextualImplicitConversion(
5850 SourceLocation Loc, Expr *From, ContextualImplicitConverter &Converter) {
5851 // We can't perform any more checking for type-dependent expressions.
5852 if (From->isTypeDependent())
5855 // Process placeholders immediately.
5856 if (From->hasPlaceholderType()) {
5857 ExprResult result = CheckPlaceholderExpr(From);
5858 if (result.isInvalid())
5860 From = result.get();
5863 // If the expression already has a matching type, we're golden.
5864 QualType T = From->getType();
5865 if (Converter.match(T))
5866 return DefaultLvalueConversion(From);
5868 // FIXME: Check for missing '()' if T is a function type?
5870 // We can only perform contextual implicit conversions on objects of class
5872 const RecordType *RecordTy = T->getAs<RecordType>();
5873 if (!RecordTy || !getLangOpts().CPlusPlus) {
5874 if (!Converter.Suppress)
5875 Converter.diagnoseNoMatch(*this, Loc, T) << From->getSourceRange();
5879 // We must have a complete class type.
5880 struct TypeDiagnoserPartialDiag : TypeDiagnoser {
5881 ContextualImplicitConverter &Converter;
5884 TypeDiagnoserPartialDiag(ContextualImplicitConverter &Converter, Expr *From)
5885 : Converter(Converter), From(From) {}
5887 void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
5888 Converter.diagnoseIncomplete(S, Loc, T) << From->getSourceRange();
5890 } IncompleteDiagnoser(Converter, From);
5892 if (Converter.Suppress ? !isCompleteType(Loc, T)
5893 : RequireCompleteType(Loc, T, IncompleteDiagnoser))
5896 // Look for a conversion to an integral or enumeration type.
5898 ViableConversions; // These are *potentially* viable in C++1y.
5899 UnresolvedSet<4> ExplicitConversions;
5900 const auto &Conversions =
5901 cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions();
5903 bool HadMultipleCandidates =
5904 (std::distance(Conversions.begin(), Conversions.end()) > 1);
5906 // To check that there is only one target type, in C++1y:
5908 bool HasUniqueTargetType = true;
5910 // Collect explicit or viable (potentially in C++1y) conversions.
5911 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
5912 NamedDecl *D = (*I)->getUnderlyingDecl();
5913 CXXConversionDecl *Conversion;
5914 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
5916 if (getLangOpts().CPlusPlus14)
5917 Conversion = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
5919 continue; // C++11 does not consider conversion operator templates(?).
5921 Conversion = cast<CXXConversionDecl>(D);
5923 assert((!ConvTemplate || getLangOpts().CPlusPlus14) &&
5924 "Conversion operator templates are considered potentially "
5927 QualType CurToType = Conversion->getConversionType().getNonReferenceType();
5928 if (Converter.match(CurToType) || ConvTemplate) {
5930 if (Conversion->isExplicit()) {
5931 // FIXME: For C++1y, do we need this restriction?
5932 // cf. diagnoseNoViableConversion()
5934 ExplicitConversions.addDecl(I.getDecl(), I.getAccess());
5936 if (!ConvTemplate && getLangOpts().CPlusPlus14) {
5937 if (ToType.isNull())
5938 ToType = CurToType.getUnqualifiedType();
5939 else if (HasUniqueTargetType &&
5940 (CurToType.getUnqualifiedType() != ToType))
5941 HasUniqueTargetType = false;
5943 ViableConversions.addDecl(I.getDecl(), I.getAccess());
5948 if (getLangOpts().CPlusPlus14) {
5950 // ... An expression e of class type E appearing in such a context
5951 // is said to be contextually implicitly converted to a specified
5952 // type T and is well-formed if and only if e can be implicitly
5953 // converted to a type T that is determined as follows: E is searched
5954 // for conversion functions whose return type is cv T or reference to
5955 // cv T such that T is allowed by the context. There shall be
5956 // exactly one such T.
5958 // If no unique T is found:
5959 if (ToType.isNull()) {
5960 if (diagnoseNoViableConversion(*this, Loc, From, Converter, T,
5961 HadMultipleCandidates,
5962 ExplicitConversions))
5964 return finishContextualImplicitConversion(*this, Loc, From, Converter);
5967 // If more than one unique Ts are found:
5968 if (!HasUniqueTargetType)
5969 return diagnoseAmbiguousConversion(*this, Loc, From, Converter, T,
5972 // If one unique T is found:
5973 // First, build a candidate set from the previously recorded
5974 // potentially viable conversions.
5975 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
5976 collectViableConversionCandidates(*this, From, ToType, ViableConversions,
5979 // Then, perform overload resolution over the candidate set.
5980 OverloadCandidateSet::iterator Best;
5981 switch (CandidateSet.BestViableFunction(*this, Loc, Best)) {
5983 // Apply this conversion.
5984 DeclAccessPair Found =
5985 DeclAccessPair::make(Best->Function, Best->FoundDecl.getAccess());
5986 if (recordConversion(*this, Loc, From, Converter, T,
5987 HadMultipleCandidates, Found))
5992 return diagnoseAmbiguousConversion(*this, Loc, From, Converter, T,
5994 case OR_No_Viable_Function:
5995 if (diagnoseNoViableConversion(*this, Loc, From, Converter, T,
5996 HadMultipleCandidates,
5997 ExplicitConversions))
6001 // We'll complain below about a non-integral condition type.
6005 switch (ViableConversions.size()) {
6007 if (diagnoseNoViableConversion(*this, Loc, From, Converter, T,
6008 HadMultipleCandidates,
6009 ExplicitConversions))
6012 // We'll complain below about a non-integral condition type.
6016 // Apply this conversion.
6017 DeclAccessPair Found = ViableConversions[0];
6018 if (recordConversion(*this, Loc, From, Converter, T,
6019 HadMultipleCandidates, Found))
6024 return diagnoseAmbiguousConversion(*this, Loc, From, Converter, T,
6029 return finishContextualImplicitConversion(*this, Loc, From, Converter);
6032 /// IsAcceptableNonMemberOperatorCandidate - Determine whether Fn is
6033 /// an acceptable non-member overloaded operator for a call whose
6034 /// arguments have types T1 (and, if non-empty, T2). This routine
6035 /// implements the check in C++ [over.match.oper]p3b2 concerning
6036 /// enumeration types.
6037 static bool IsAcceptableNonMemberOperatorCandidate(ASTContext &Context,
6039 ArrayRef<Expr *> Args) {
6040 QualType T1 = Args[0]->getType();
6041 QualType T2 = Args.size() > 1 ? Args[1]->getType() : QualType();
6043 if (T1->isDependentType() || (!T2.isNull() && T2->isDependentType()))
6046 if (T1->isRecordType() || (!T2.isNull() && T2->isRecordType()))
6049 const FunctionProtoType *Proto = Fn->getType()->getAs<FunctionProtoType>();
6050 if (Proto->getNumParams() < 1)
6053 if (T1->isEnumeralType()) {
6054 QualType ArgType = Proto->getParamType(0).getNonReferenceType();
6055 if (Context.hasSameUnqualifiedType(T1, ArgType))
6059 if (Proto->getNumParams() < 2)
6062 if (!T2.isNull() && T2->isEnumeralType()) {
6063 QualType ArgType = Proto->getParamType(1).getNonReferenceType();
6064 if (Context.hasSameUnqualifiedType(T2, ArgType))
6071 /// AddOverloadCandidate - Adds the given function to the set of
6072 /// candidate functions, using the given function call arguments. If
6073 /// @p SuppressUserConversions, then don't allow user-defined
6074 /// conversions via constructors or conversion operators.
6076 /// \param PartialOverloading true if we are performing "partial" overloading
6077 /// based on an incomplete set of function arguments. This feature is used by
6078 /// code completion.
6079 void Sema::AddOverloadCandidate(
6080 FunctionDecl *Function, DeclAccessPair FoundDecl, ArrayRef<Expr *> Args,
6081 OverloadCandidateSet &CandidateSet, bool SuppressUserConversions,
6082 bool PartialOverloading, bool AllowExplicit, bool AllowExplicitConversions,
6083 ADLCallKind IsADLCandidate, ConversionSequenceList EarlyConversions,
6084 OverloadCandidateParamOrder PO) {
6085 const FunctionProtoType *Proto
6086 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>());
6087 assert(Proto && "Functions without a prototype cannot be overloaded");
6088 assert(!Function->getDescribedFunctionTemplate() &&
6089 "Use AddTemplateOverloadCandidate for function templates");
6091 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) {
6092 if (!isa<CXXConstructorDecl>(Method)) {
6093 // If we get here, it's because we're calling a member function
6094 // that is named without a member access expression (e.g.,
6095 // "this->f") that was either written explicitly or created
6096 // implicitly. This can happen with a qualified call to a member
6097 // function, e.g., X::f(). We use an empty type for the implied
6098 // object argument (C++ [over.call.func]p3), and the acting context
6100 AddMethodCandidate(Method, FoundDecl, Method->getParent(), QualType(),
6101 Expr::Classification::makeSimpleLValue(), Args,
6102 CandidateSet, SuppressUserConversions,
6103 PartialOverloading, EarlyConversions, PO);
6106 // We treat a constructor like a non-member function, since its object
6107 // argument doesn't participate in overload resolution.
6110 if (!CandidateSet.isNewCandidate(Function, PO))
6113 // C++11 [class.copy]p11: [DR1402]
6114 // A defaulted move constructor that is defined as deleted is ignored by
6115 // overload resolution.
6116 CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function);
6117 if (Constructor && Constructor->isDefaulted() && Constructor->isDeleted() &&
6118 Constructor->isMoveConstructor())
6121 // Overload resolution is always an unevaluated context.
6122 EnterExpressionEvaluationContext Unevaluated(
6123 *this, Sema::ExpressionEvaluationContext::Unevaluated);
6125 // C++ [over.match.oper]p3:
6126 // if no operand has a class type, only those non-member functions in the
6127 // lookup set that have a first parameter of type T1 or "reference to
6128 // (possibly cv-qualified) T1", when T1 is an enumeration type, or (if there
6129 // is a right operand) a second parameter of type T2 or "reference to
6130 // (possibly cv-qualified) T2", when T2 is an enumeration type, are
6131 // candidate functions.
6132 if (CandidateSet.getKind() == OverloadCandidateSet::CSK_Operator &&
6133 !IsAcceptableNonMemberOperatorCandidate(Context, Function, Args))
6136 // Add this candidate
6137 OverloadCandidate &Candidate =
6138 CandidateSet.addCandidate(Args.size(), EarlyConversions);
6139 Candidate.FoundDecl = FoundDecl;
6140 Candidate.Function = Function;
6141 Candidate.Viable = true;
6142 Candidate.RewriteKind =
6143 CandidateSet.getRewriteInfo().getRewriteKind(Function, PO);
6144 Candidate.IsSurrogate = false;
6145 Candidate.IsADLCandidate = IsADLCandidate;
6146 Candidate.IgnoreObjectArgument = false;
6147 Candidate.ExplicitCallArguments = Args.size();
6149 if (Function->isMultiVersion() && Function->hasAttr<TargetAttr>() &&
6150 !Function->getAttr<TargetAttr>()->isDefaultVersion()) {
6151 Candidate.Viable = false;
6152 Candidate.FailureKind = ovl_non_default_multiversion_function;
6157 // C++ [class.copy]p3:
6158 // A member function template is never instantiated to perform the copy
6159 // of a class object to an object of its class type.
6160 QualType ClassType = Context.getTypeDeclType(Constructor->getParent());
6161 if (Args.size() == 1 && Constructor->isSpecializationCopyingObject() &&
6162 (Context.hasSameUnqualifiedType(ClassType, Args[0]->getType()) ||
6163 IsDerivedFrom(Args[0]->getBeginLoc(), Args[0]->getType(),
6165 Candidate.Viable = false;
6166 Candidate.FailureKind = ovl_fail_illegal_constructor;
6170 // C++ [over.match.funcs]p8: (proposed DR resolution)
6171 // A constructor inherited from class type C that has a first parameter
6172 // of type "reference to P" (including such a constructor instantiated
6173 // from a template) is excluded from the set of candidate functions when
6174 // constructing an object of type cv D if the argument list has exactly
6175 // one argument and D is reference-related to P and P is reference-related
6177 auto *Shadow = dyn_cast<ConstructorUsingShadowDecl>(FoundDecl.getDecl());
6178 if (Shadow && Args.size() == 1 && Constructor->getNumParams() >= 1 &&
6179 Constructor->getParamDecl(0)->getType()->isReferenceType()) {
6180 QualType P = Constructor->getParamDecl(0)->getType()->getPointeeType();
6181 QualType C = Context.getRecordType(Constructor->getParent());
6182 QualType D = Context.getRecordType(Shadow->getParent());
6183 SourceLocation Loc = Args.front()->getExprLoc();
6184 if ((Context.hasSameUnqualifiedType(P, C) || IsDerivedFrom(Loc, P, C)) &&
6185 (Context.hasSameUnqualifiedType(D, P) || IsDerivedFrom(Loc, D, P))) {
6186 Candidate.Viable = false;
6187 Candidate.FailureKind = ovl_fail_inhctor_slice;
6192 // Check that the constructor is capable of constructing an object in the
6193 // destination address space.
6194 if (!Qualifiers::isAddressSpaceSupersetOf(
6195 Constructor->getMethodQualifiers().getAddressSpace(),
6196 CandidateSet.getDestAS())) {
6197 Candidate.Viable = false;
6198 Candidate.FailureKind = ovl_fail_object_addrspace_mismatch;
6202 unsigned NumParams = Proto->getNumParams();
6204 // (C++ 13.3.2p2): A candidate function having fewer than m
6205 // parameters is viable only if it has an ellipsis in its parameter
6207 if (TooManyArguments(NumParams, Args.size(), PartialOverloading) &&
6208 !Proto->isVariadic()) {
6209 Candidate.Viable = false;
6210 Candidate.FailureKind = ovl_fail_too_many_arguments;
6214 // (C++ 13.3.2p2): A candidate function having more than m parameters
6215 // is viable only if the (m+1)st parameter has a default argument
6216 // (8.3.6). For the purposes of overload resolution, the
6217 // parameter list is truncated on the right, so that there are
6218 // exactly m parameters.
6219 unsigned MinRequiredArgs = Function->getMinRequiredArguments();
6220 if (Args.size() < MinRequiredArgs && !PartialOverloading) {
6221 // Not enough arguments.
6222 Candidate.Viable = false;
6223 Candidate.FailureKind = ovl_fail_too_few_arguments;
6227 // (CUDA B.1): Check for invalid calls between targets.
6228 if (getLangOpts().CUDA)
6229 if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext))
6230 // Skip the check for callers that are implicit members, because in this
6231 // case we may not yet know what the member's target is; the target is
6232 // inferred for the member automatically, based on the bases and fields of
6234 if (!Caller->isImplicit() && !IsAllowedCUDACall(Caller, Function)) {
6235 Candidate.Viable = false;
6236 Candidate.FailureKind = ovl_fail_bad_target;
6240 // Determine the implicit conversion sequences for each of the
6242 for (unsigned ArgIdx = 0; ArgIdx < Args.size(); ++ArgIdx) {
6244 PO == OverloadCandidateParamOrder::Reversed ? 1 - ArgIdx : ArgIdx;
6245 if (Candidate.Conversions[ConvIdx].isInitialized()) {
6246 // We already formed a conversion sequence for this parameter during
6247 // template argument deduction.
6248 } else if (ArgIdx < NumParams) {
6249 // (C++ 13.3.2p3): for F to be a viable function, there shall
6250 // exist for each argument an implicit conversion sequence
6251 // (13.3.3.1) that converts that argument to the corresponding
6253 QualType ParamType = Proto->getParamType(ArgIdx);
6254 Candidate.Conversions[ConvIdx] = TryCopyInitialization(
6255 *this, Args[ArgIdx], ParamType, SuppressUserConversions,
6256 /*InOverloadResolution=*/true,
6257 /*AllowObjCWritebackConversion=*/
6258 getLangOpts().ObjCAutoRefCount, AllowExplicitConversions);
6259 if (Candidate.Conversions[ConvIdx].isBad()) {
6260 Candidate.Viable = false;
6261 Candidate.FailureKind = ovl_fail_bad_conversion;
6265 // (C++ 13.3.2p2): For the purposes of overload resolution, any
6266 // argument for which there is no corresponding parameter is
6267 // considered to ""match the ellipsis" (C+ 13.3.3.1.3).
6268 Candidate.Conversions[ConvIdx].setEllipsis();
6272 if (!AllowExplicit) {
6273 ExplicitSpecifier ES = ExplicitSpecifier::getFromDecl(Function);
6274 if (ES.getKind() != ExplicitSpecKind::ResolvedFalse) {
6275 Candidate.Viable = false;
6276 Candidate.FailureKind = ovl_fail_explicit_resolved;
6281 if (EnableIfAttr *FailedAttr = CheckEnableIf(Function, Args)) {
6282 Candidate.Viable = false;
6283 Candidate.FailureKind = ovl_fail_enable_if;
6284 Candidate.DeductionFailure.Data = FailedAttr;
6288 if (LangOpts.OpenCL && isOpenCLDisabledDecl(Function)) {
6289 Candidate.Viable = false;
6290 Candidate.FailureKind = ovl_fail_ext_disabled;
6296 Sema::SelectBestMethod(Selector Sel, MultiExprArg Args, bool IsInstance,
6297 SmallVectorImpl<ObjCMethodDecl *> &Methods) {
6298 if (Methods.size() <= 1)
6301 for (unsigned b = 0, e = Methods.size(); b < e; b++) {
6303 ObjCMethodDecl *Method = Methods[b];
6304 unsigned NumNamedArgs = Sel.getNumArgs();
6305 // Method might have more arguments than selector indicates. This is due
6306 // to addition of c-style arguments in method.
6307 if (Method->param_size() > NumNamedArgs)
6308 NumNamedArgs = Method->param_size();
6309 if (Args.size() < NumNamedArgs)
6312 for (unsigned i = 0; i < NumNamedArgs; i++) {
6313 // We can't do any type-checking on a type-dependent argument.
6314 if (Args[i]->isTypeDependent()) {
6319 ParmVarDecl *param = Method->parameters()[i];
6320 Expr *argExpr = Args[i];
6321 assert(argExpr && "SelectBestMethod(): missing expression");
6323 // Strip the unbridged-cast placeholder expression off unless it's
6324 // a consumed argument.
6325 if (argExpr->hasPlaceholderType(BuiltinType::ARCUnbridgedCast) &&
6326 !param->hasAttr<CFConsumedAttr>())
6327 argExpr = stripARCUnbridgedCast(argExpr);
6329 // If the parameter is __unknown_anytype, move on to the next method.
6330 if (param->getType() == Context.UnknownAnyTy) {
6335 ImplicitConversionSequence ConversionState
6336 = TryCopyInitialization(*this, argExpr, param->getType(),
6337 /*SuppressUserConversions*/false,
6338 /*InOverloadResolution=*/true,
6339 /*AllowObjCWritebackConversion=*/
6340 getLangOpts().ObjCAutoRefCount,
6341 /*AllowExplicit*/false);
6342 // This function looks for a reasonably-exact match, so we consider
6343 // incompatible pointer conversions to be a failure here.
6344 if (ConversionState.isBad() ||
6345 (ConversionState.isStandard() &&
6346 ConversionState.Standard.Second ==
6347 ICK_Incompatible_Pointer_Conversion)) {
6352 // Promote additional arguments to variadic methods.
6353 if (Match && Method->isVariadic()) {
6354 for (unsigned i = NumNamedArgs, e = Args.size(); i < e; ++i) {
6355 if (Args[i]->isTypeDependent()) {
6359 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod,
6361 if (Arg.isInvalid()) {
6367 // Check for extra arguments to non-variadic methods.
6368 if (Args.size() != NumNamedArgs)
6370 else if (Match && NumNamedArgs == 0 && Methods.size() > 1) {
6371 // Special case when selectors have no argument. In this case, select
6372 // one with the most general result type of 'id'.
6373 for (unsigned b = 0, e = Methods.size(); b < e; b++) {
6374 QualType ReturnT = Methods[b]->getReturnType();
6375 if (ReturnT->isObjCIdType())
6388 convertArgsForAvailabilityChecks(Sema &S, FunctionDecl *Function, Expr *ThisArg,
6389 ArrayRef<Expr *> Args, Sema::SFINAETrap &Trap,
6390 bool MissingImplicitThis, Expr *&ConvertedThis,
6391 SmallVectorImpl<Expr *> &ConvertedArgs) {
6393 CXXMethodDecl *Method = cast<CXXMethodDecl>(Function);
6394 assert(!isa<CXXConstructorDecl>(Method) &&
6395 "Shouldn't have `this` for ctors!");
6396 assert(!Method->isStatic() && "Shouldn't have `this` for static methods!");
6397 ExprResult R = S.PerformObjectArgumentInitialization(
6398 ThisArg, /*Qualifier=*/nullptr, Method, Method);
6401 ConvertedThis = R.get();
6403 if (auto *MD = dyn_cast<CXXMethodDecl>(Function)) {
6405 assert((MissingImplicitThis || MD->isStatic() ||
6406 isa<CXXConstructorDecl>(MD)) &&
6407 "Expected `this` for non-ctor instance methods");
6409 ConvertedThis = nullptr;
6412 // Ignore any variadic arguments. Converting them is pointless, since the
6413 // user can't refer to them in the function condition.
6414 unsigned ArgSizeNoVarargs = std::min(Function->param_size(), Args.size());
6416 // Convert the arguments.
6417 for (unsigned I = 0; I != ArgSizeNoVarargs; ++I) {
6419 R = S.PerformCopyInitialization(InitializedEntity::InitializeParameter(
6420 S.Context, Function->getParamDecl(I)),
6421 SourceLocation(), Args[I]);
6426 ConvertedArgs.push_back(R.get());
6429 if (Trap.hasErrorOccurred())
6432 // Push default arguments if needed.
6433 if (!Function->isVariadic() && Args.size() < Function->getNumParams()) {
6434 for (unsigned i = Args.size(), e = Function->getNumParams(); i != e; ++i) {
6435 ParmVarDecl *P = Function->getParamDecl(i);
6436 Expr *DefArg = P->hasUninstantiatedDefaultArg()
6437 ? P->getUninstantiatedDefaultArg()
6438 : P->getDefaultArg();
6439 // This can only happen in code completion, i.e. when PartialOverloading
6444 S.PerformCopyInitialization(InitializedEntity::InitializeParameter(
6445 S.Context, Function->getParamDecl(i)),
6446 SourceLocation(), DefArg);
6449 ConvertedArgs.push_back(R.get());
6452 if (Trap.hasErrorOccurred())
6458 EnableIfAttr *Sema::CheckEnableIf(FunctionDecl *Function, ArrayRef<Expr *> Args,
6459 bool MissingImplicitThis) {
6460 auto EnableIfAttrs = Function->specific_attrs<EnableIfAttr>();
6461 if (EnableIfAttrs.begin() == EnableIfAttrs.end())
6464 SFINAETrap Trap(*this);
6465 SmallVector<Expr *, 16> ConvertedArgs;
6466 // FIXME: We should look into making enable_if late-parsed.
6467 Expr *DiscardedThis;
6468 if (!convertArgsForAvailabilityChecks(
6469 *this, Function, /*ThisArg=*/nullptr, Args, Trap,
6470 /*MissingImplicitThis=*/true, DiscardedThis, ConvertedArgs))
6471 return *EnableIfAttrs.begin();
6473 for (auto *EIA : EnableIfAttrs) {
6475 // FIXME: This doesn't consider value-dependent cases, because doing so is
6476 // very difficult. Ideally, we should handle them more gracefully.
6477 if (EIA->getCond()->isValueDependent() ||
6478 !EIA->getCond()->EvaluateWithSubstitution(
6479 Result, Context, Function, llvm::makeArrayRef(ConvertedArgs)))
6482 if (!Result.isInt() || !Result.getInt().getBoolValue())
6488 template <typename CheckFn>
6489 static bool diagnoseDiagnoseIfAttrsWith(Sema &S, const NamedDecl *ND,
6490 bool ArgDependent, SourceLocation Loc,
6491 CheckFn &&IsSuccessful) {
6492 SmallVector<const DiagnoseIfAttr *, 8> Attrs;
6493 for (const auto *DIA : ND->specific_attrs<DiagnoseIfAttr>()) {
6494 if (ArgDependent == DIA->getArgDependent())
6495 Attrs.push_back(DIA);
6498 // Common case: No diagnose_if attributes, so we can quit early.
6502 auto WarningBegin = std::stable_partition(
6503 Attrs.begin(), Attrs.end(),
6504 [](const DiagnoseIfAttr *DIA) { return DIA->isError(); });
6506 // Note that diagnose_if attributes are late-parsed, so they appear in the
6507 // correct order (unlike enable_if attributes).
6508 auto ErrAttr = llvm::find_if(llvm::make_range(Attrs.begin(), WarningBegin),
6510 if (ErrAttr != WarningBegin) {
6511 const DiagnoseIfAttr *DIA = *ErrAttr;
6512 S.Diag(Loc, diag::err_diagnose_if_succeeded) << DIA->getMessage();
6513 S.Diag(DIA->getLocation(), diag::note_from_diagnose_if)
6514 << DIA->getParent() << DIA->getCond()->getSourceRange();
6518 for (const auto *DIA : llvm::make_range(WarningBegin, Attrs.end()))
6519 if (IsSuccessful(DIA)) {
6520 S.Diag(Loc, diag::warn_diagnose_if_succeeded) << DIA->getMessage();
6521 S.Diag(DIA->getLocation(), diag::note_from_diagnose_if)
6522 << DIA->getParent() << DIA->getCond()->getSourceRange();
6528 bool Sema::diagnoseArgDependentDiagnoseIfAttrs(const FunctionDecl *Function,
6529 const Expr *ThisArg,
6530 ArrayRef<const Expr *> Args,
6531 SourceLocation Loc) {
6532 return diagnoseDiagnoseIfAttrsWith(
6533 *this, Function, /*ArgDependent=*/true, Loc,
6534 [&](const DiagnoseIfAttr *DIA) {
6536 // It's sane to use the same Args for any redecl of this function, since
6537 // EvaluateWithSubstitution only cares about the position of each
6538 // argument in the arg list, not the ParmVarDecl* it maps to.
6539 if (!DIA->getCond()->EvaluateWithSubstitution(
6540 Result, Context, cast<FunctionDecl>(DIA->getParent()), Args, ThisArg))
6542 return Result.isInt() && Result.getInt().getBoolValue();
6546 bool Sema::diagnoseArgIndependentDiagnoseIfAttrs(const NamedDecl *ND,
6547 SourceLocation Loc) {
6548 return diagnoseDiagnoseIfAttrsWith(
6549 *this, ND, /*ArgDependent=*/false, Loc,
6550 [&](const DiagnoseIfAttr *DIA) {
6552 return DIA->getCond()->EvaluateAsBooleanCondition(Result, Context) &&
6557 /// Add all of the function declarations in the given function set to
6558 /// the overload candidate set.
6559 void Sema::AddFunctionCandidates(const UnresolvedSetImpl &Fns,
6560 ArrayRef<Expr *> Args,
6561 OverloadCandidateSet &CandidateSet,
6562 TemplateArgumentListInfo *ExplicitTemplateArgs,
6563 bool SuppressUserConversions,
6564 bool PartialOverloading,
6565 bool FirstArgumentIsBase) {
6566 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) {
6567 NamedDecl *D = F.getDecl()->getUnderlyingDecl();
6568 ArrayRef<Expr *> FunctionArgs = Args;
6570 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D);
6572 FunTmpl ? FunTmpl->getTemplatedDecl() : cast<FunctionDecl>(D);
6574 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) {
6575 QualType ObjectType;
6576 Expr::Classification ObjectClassification;
6577 if (Args.size() > 0) {
6578 if (Expr *E = Args[0]) {
6579 // Use the explicit base to restrict the lookup:
6580 ObjectType = E->getType();
6581 // Pointers in the object arguments are implicitly dereferenced, so we
6582 // always classify them as l-values.
6583 if (!ObjectType.isNull() && ObjectType->isPointerType())
6584 ObjectClassification = Expr::Classification::makeSimpleLValue();
6586 ObjectClassification = E->Classify(Context);
6587 } // .. else there is an implicit base.
6588 FunctionArgs = Args.slice(1);
6591 AddMethodTemplateCandidate(
6592 FunTmpl, F.getPair(),
6593 cast<CXXRecordDecl>(FunTmpl->getDeclContext()),
6594 ExplicitTemplateArgs, ObjectType, ObjectClassification,
6595 FunctionArgs, CandidateSet, SuppressUserConversions,
6596 PartialOverloading);
6598 AddMethodCandidate(cast<CXXMethodDecl>(FD), F.getPair(),
6599 cast<CXXMethodDecl>(FD)->getParent(), ObjectType,
6600 ObjectClassification, FunctionArgs, CandidateSet,
6601 SuppressUserConversions, PartialOverloading);
6604 // This branch handles both standalone functions and static methods.
6606 // Slice the first argument (which is the base) when we access
6607 // static method as non-static.
6608 if (Args.size() > 0 &&
6609 (!Args[0] || (FirstArgumentIsBase && isa<CXXMethodDecl>(FD) &&
6610 !isa<CXXConstructorDecl>(FD)))) {
6611 assert(cast<CXXMethodDecl>(FD)->isStatic());
6612 FunctionArgs = Args.slice(1);
6615 AddTemplateOverloadCandidate(FunTmpl, F.getPair(),
6616 ExplicitTemplateArgs, FunctionArgs,
6617 CandidateSet, SuppressUserConversions,
6618 PartialOverloading);
6620 AddOverloadCandidate(FD, F.getPair(), FunctionArgs, CandidateSet,
6621 SuppressUserConversions, PartialOverloading);
6627 /// AddMethodCandidate - Adds a named decl (which is some kind of
6628 /// method) as a method candidate to the given overload set.
6629 void Sema::AddMethodCandidate(DeclAccessPair FoundDecl, QualType ObjectType,
6630 Expr::Classification ObjectClassification,
6631 ArrayRef<Expr *> Args,
6632 OverloadCandidateSet &CandidateSet,
6633 bool SuppressUserConversions,
6634 OverloadCandidateParamOrder PO) {
6635 NamedDecl *Decl = FoundDecl.getDecl();
6636 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(Decl->getDeclContext());
6638 if (isa<UsingShadowDecl>(Decl))
6639 Decl = cast<UsingShadowDecl>(Decl)->getTargetDecl();
6641 if (FunctionTemplateDecl *TD = dyn_cast<FunctionTemplateDecl>(Decl)) {
6642 assert(isa<CXXMethodDecl>(TD->getTemplatedDecl()) &&
6643 "Expected a member function template");
6644 AddMethodTemplateCandidate(TD, FoundDecl, ActingContext,
6645 /*ExplicitArgs*/ nullptr, ObjectType,
6646 ObjectClassification, Args, CandidateSet,
6647 SuppressUserConversions, false, PO);
6649 AddMethodCandidate(cast<CXXMethodDecl>(Decl), FoundDecl, ActingContext,
6650 ObjectType, ObjectClassification, Args, CandidateSet,
6651 SuppressUserConversions, false, None, PO);
6655 /// AddMethodCandidate - Adds the given C++ member function to the set
6656 /// of candidate functions, using the given function call arguments
6657 /// and the object argument (@c Object). For example, in a call
6658 /// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain
6659 /// both @c a1 and @c a2. If @p SuppressUserConversions, then don't
6660 /// allow user-defined conversions via constructors or conversion
6663 Sema::AddMethodCandidate(CXXMethodDecl *Method, DeclAccessPair FoundDecl,
6664 CXXRecordDecl *ActingContext, QualType ObjectType,
6665 Expr::Classification ObjectClassification,
6666 ArrayRef<Expr *> Args,
6667 OverloadCandidateSet &CandidateSet,
6668 bool SuppressUserConversions,
6669 bool PartialOverloading,
6670 ConversionSequenceList EarlyConversions,
6671 OverloadCandidateParamOrder PO) {
6672 const FunctionProtoType *Proto
6673 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>());
6674 assert(Proto && "Methods without a prototype cannot be overloaded");
6675 assert(!isa<CXXConstructorDecl>(Method) &&
6676 "Use AddOverloadCandidate for constructors");
6678 if (!CandidateSet.isNewCandidate(Method, PO))
6681 // C++11 [class.copy]p23: [DR1402]
6682 // A defaulted move assignment operator that is defined as deleted is
6683 // ignored by overload resolution.
6684 if (Method->isDefaulted() && Method->isDeleted() &&
6685 Method->isMoveAssignmentOperator())
6688 // Overload resolution is always an unevaluated context.
6689 EnterExpressionEvaluationContext Unevaluated(
6690 *this, Sema::ExpressionEvaluationContext::Unevaluated);
6692 // Add this candidate
6693 OverloadCandidate &Candidate =
6694 CandidateSet.addCandidate(Args.size() + 1, EarlyConversions);
6695 Candidate.FoundDecl = FoundDecl;
6696 Candidate.Function = Method;
6697 Candidate.RewriteKind =
6698 CandidateSet.getRewriteInfo().getRewriteKind(Method, PO);
6699 Candidate.IsSurrogate = false;
6700 Candidate.IgnoreObjectArgument = false;
6701 Candidate.ExplicitCallArguments = Args.size();
6703 unsigned NumParams = Proto->getNumParams();
6705 // (C++ 13.3.2p2): A candidate function having fewer than m
6706 // parameters is viable only if it has an ellipsis in its parameter
6708 if (TooManyArguments(NumParams, Args.size(), PartialOverloading) &&
6709 !Proto->isVariadic()) {
6710 Candidate.Viable = false;
6711 Candidate.FailureKind = ovl_fail_too_many_arguments;
6715 // (C++ 13.3.2p2): A candidate function having more than m parameters
6716 // is viable only if the (m+1)st parameter has a default argument
6717 // (8.3.6). For the purposes of overload resolution, the
6718 // parameter list is truncated on the right, so that there are
6719 // exactly m parameters.
6720 unsigned MinRequiredArgs = Method->getMinRequiredArguments();
6721 if (Args.size() < MinRequiredArgs && !PartialOverloading) {
6722 // Not enough arguments.
6723 Candidate.Viable = false;
6724 Candidate.FailureKind = ovl_fail_too_few_arguments;
6728 Candidate.Viable = true;
6730 if (Method->isStatic() || ObjectType.isNull())
6731 // The implicit object argument is ignored.
6732 Candidate.IgnoreObjectArgument = true;
6734 unsigned ConvIdx = PO == OverloadCandidateParamOrder::Reversed ? 1 : 0;
6735 // Determine the implicit conversion sequence for the object
6737 Candidate.Conversions[ConvIdx] = TryObjectArgumentInitialization(
6738 *this, CandidateSet.getLocation(), ObjectType, ObjectClassification,
6739 Method, ActingContext);
6740 if (Candidate.Conversions[ConvIdx].isBad()) {
6741 Candidate.Viable = false;
6742 Candidate.FailureKind = ovl_fail_bad_conversion;
6747 // (CUDA B.1): Check for invalid calls between targets.
6748 if (getLangOpts().CUDA)
6749 if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext))
6750 if (!IsAllowedCUDACall(Caller, Method)) {
6751 Candidate.Viable = false;
6752 Candidate.FailureKind = ovl_fail_bad_target;
6756 // Determine the implicit conversion sequences for each of the
6758 for (unsigned ArgIdx = 0; ArgIdx < Args.size(); ++ArgIdx) {
6760 PO == OverloadCandidateParamOrder::Reversed ? 0 : (ArgIdx + 1);
6761 if (Candidate.Conversions[ConvIdx].isInitialized()) {
6762 // We already formed a conversion sequence for this parameter during
6763 // template argument deduction.
6764 } else if (ArgIdx < NumParams) {
6765 // (C++ 13.3.2p3): for F to be a viable function, there shall
6766 // exist for each argument an implicit conversion sequence
6767 // (13.3.3.1) that converts that argument to the corresponding
6769 QualType ParamType = Proto->getParamType(ArgIdx);
6770 Candidate.Conversions[ConvIdx]
6771 = TryCopyInitialization(*this, Args[ArgIdx], ParamType,
6772 SuppressUserConversions,
6773 /*InOverloadResolution=*/true,
6774 /*AllowObjCWritebackConversion=*/
6775 getLangOpts().ObjCAutoRefCount);
6776 if (Candidate.Conversions[ConvIdx].isBad()) {
6777 Candidate.Viable = false;
6778 Candidate.FailureKind = ovl_fail_bad_conversion;
6782 // (C++ 13.3.2p2): For the purposes of overload resolution, any
6783 // argument for which there is no corresponding parameter is
6784 // considered to "match the ellipsis" (C+ 13.3.3.1.3).
6785 Candidate.Conversions[ConvIdx].setEllipsis();
6789 if (EnableIfAttr *FailedAttr = CheckEnableIf(Method, Args, true)) {
6790 Candidate.Viable = false;
6791 Candidate.FailureKind = ovl_fail_enable_if;
6792 Candidate.DeductionFailure.Data = FailedAttr;
6796 if (Method->isMultiVersion() && Method->hasAttr<TargetAttr>() &&
6797 !Method->getAttr<TargetAttr>()->isDefaultVersion()) {
6798 Candidate.Viable = false;
6799 Candidate.FailureKind = ovl_non_default_multiversion_function;
6803 /// Add a C++ member function template as a candidate to the candidate
6804 /// set, using template argument deduction to produce an appropriate member
6805 /// function template specialization.
6806 void Sema::AddMethodTemplateCandidate(
6807 FunctionTemplateDecl *MethodTmpl, DeclAccessPair FoundDecl,
6808 CXXRecordDecl *ActingContext,
6809 TemplateArgumentListInfo *ExplicitTemplateArgs, QualType ObjectType,
6810 Expr::Classification ObjectClassification, ArrayRef<Expr *> Args,
6811 OverloadCandidateSet &CandidateSet, bool SuppressUserConversions,
6812 bool PartialOverloading, OverloadCandidateParamOrder PO) {
6813 if (!CandidateSet.isNewCandidate(MethodTmpl, PO))
6816 // C++ [over.match.funcs]p7:
6817 // In each case where a candidate is a function template, candidate
6818 // function template specializations are generated using template argument
6819 // deduction (14.8.3, 14.8.2). Those candidates are then handled as
6820 // candidate functions in the usual way.113) A given name can refer to one
6821 // or more function templates and also to a set of overloaded non-template
6822 // functions. In such a case, the candidate functions generated from each
6823 // function template are combined with the set of non-template candidate
6825 TemplateDeductionInfo Info(CandidateSet.getLocation());
6826 FunctionDecl *Specialization = nullptr;
6827 ConversionSequenceList Conversions;
6828 if (TemplateDeductionResult Result = DeduceTemplateArguments(
6829 MethodTmpl, ExplicitTemplateArgs, Args, Specialization, Info,
6830 PartialOverloading, [&](ArrayRef<QualType> ParamTypes) {
6831 return CheckNonDependentConversions(
6832 MethodTmpl, ParamTypes, Args, CandidateSet, Conversions,
6833 SuppressUserConversions, ActingContext, ObjectType,
6834 ObjectClassification, PO);
6836 OverloadCandidate &Candidate =
6837 CandidateSet.addCandidate(Conversions.size(), Conversions);
6838 Candidate.FoundDecl = FoundDecl;
6839 Candidate.Function = MethodTmpl->getTemplatedDecl();
6840 Candidate.Viable = false;
6841 Candidate.RewriteKind =
6842 CandidateSet.getRewriteInfo().getRewriteKind(Candidate.Function, PO);
6843 Candidate.IsSurrogate = false;
6844 Candidate.IgnoreObjectArgument =
6845 cast<CXXMethodDecl>(Candidate.Function)->isStatic() ||
6846 ObjectType.isNull();
6847 Candidate.ExplicitCallArguments = Args.size();
6848 if (Result == TDK_NonDependentConversionFailure)
6849 Candidate.FailureKind = ovl_fail_bad_conversion;
6851 Candidate.FailureKind = ovl_fail_bad_deduction;
6852 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result,
6858 // Add the function template specialization produced by template argument
6859 // deduction as a candidate.
6860 assert(Specialization && "Missing member function template specialization?");
6861 assert(isa<CXXMethodDecl>(Specialization) &&
6862 "Specialization is not a member function?");
6863 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), FoundDecl,
6864 ActingContext, ObjectType, ObjectClassification, Args,
6865 CandidateSet, SuppressUserConversions, PartialOverloading,
6869 /// Add a C++ function template specialization as a candidate
6870 /// in the candidate set, using template argument deduction to produce
6871 /// an appropriate function template specialization.
6872 void Sema::AddTemplateOverloadCandidate(
6873 FunctionTemplateDecl *FunctionTemplate, DeclAccessPair FoundDecl,
6874 TemplateArgumentListInfo *ExplicitTemplateArgs, ArrayRef<Expr *> Args,
6875 OverloadCandidateSet &CandidateSet, bool SuppressUserConversions,
6876 bool PartialOverloading, bool AllowExplicit, ADLCallKind IsADLCandidate,
6877 OverloadCandidateParamOrder PO) {
6878 if (!CandidateSet.isNewCandidate(FunctionTemplate, PO))
6881 // C++ [over.match.funcs]p7:
6882 // In each case where a candidate is a function template, candidate
6883 // function template specializations are generated using template argument
6884 // deduction (14.8.3, 14.8.2). Those candidates are then handled as
6885 // candidate functions in the usual way.113) A given name can refer to one
6886 // or more function templates and also to a set of overloaded non-template
6887 // functions. In such a case, the candidate functions generated from each
6888 // function template are combined with the set of non-template candidate
6890 TemplateDeductionInfo Info(CandidateSet.getLocation());
6891 FunctionDecl *Specialization = nullptr;
6892 ConversionSequenceList Conversions;
6893 if (TemplateDeductionResult Result = DeduceTemplateArguments(
6894 FunctionTemplate, ExplicitTemplateArgs, Args, Specialization, Info,
6895 PartialOverloading, [&](ArrayRef<QualType> ParamTypes) {
6896 return CheckNonDependentConversions(
6897 FunctionTemplate, ParamTypes, Args, CandidateSet, Conversions,
6898 SuppressUserConversions, nullptr, QualType(), {}, PO);
6900 OverloadCandidate &Candidate =
6901 CandidateSet.addCandidate(Conversions.size(), Conversions);
6902 Candidate.FoundDecl = FoundDecl;
6903 Candidate.Function = FunctionTemplate->getTemplatedDecl();
6904 Candidate.Viable = false;
6905 Candidate.RewriteKind =
6906 CandidateSet.getRewriteInfo().getRewriteKind(Candidate.Function, PO);
6907 Candidate.IsSurrogate = false;
6908 Candidate.IsADLCandidate = IsADLCandidate;
6909 // Ignore the object argument if there is one, since we don't have an object
6911 Candidate.IgnoreObjectArgument =
6912 isa<CXXMethodDecl>(Candidate.Function) &&
6913 !isa<CXXConstructorDecl>(Candidate.Function);
6914 Candidate.ExplicitCallArguments = Args.size();
6915 if (Result == TDK_NonDependentConversionFailure)
6916 Candidate.FailureKind = ovl_fail_bad_conversion;
6918 Candidate.FailureKind = ovl_fail_bad_deduction;
6919 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result,
6925 // Add the function template specialization produced by template argument
6926 // deduction as a candidate.
6927 assert(Specialization && "Missing function template specialization?");
6928 AddOverloadCandidate(
6929 Specialization, FoundDecl, Args, CandidateSet, SuppressUserConversions,
6930 PartialOverloading, AllowExplicit,
6931 /*AllowExplicitConversions*/ false, IsADLCandidate, Conversions, PO);
6934 /// Check that implicit conversion sequences can be formed for each argument
6935 /// whose corresponding parameter has a non-dependent type, per DR1391's
6936 /// [temp.deduct.call]p10.
6937 bool Sema::CheckNonDependentConversions(
6938 FunctionTemplateDecl *FunctionTemplate, ArrayRef<QualType> ParamTypes,
6939 ArrayRef<Expr *> Args, OverloadCandidateSet &CandidateSet,
6940 ConversionSequenceList &Conversions, bool SuppressUserConversions,
6941 CXXRecordDecl *ActingContext, QualType ObjectType,
6942 Expr::Classification ObjectClassification, OverloadCandidateParamOrder PO) {
6943 // FIXME: The cases in which we allow explicit conversions for constructor
6944 // arguments never consider calling a constructor template. It's not clear
6946 const bool AllowExplicit = false;
6948 auto *FD = FunctionTemplate->getTemplatedDecl();
6949 auto *Method = dyn_cast<CXXMethodDecl>(FD);
6950 bool HasThisConversion = Method && !isa<CXXConstructorDecl>(Method);
6951 unsigned ThisConversions = HasThisConversion ? 1 : 0;
6954 CandidateSet.allocateConversionSequences(ThisConversions + Args.size());
6956 // Overload resolution is always an unevaluated context.
6957 EnterExpressionEvaluationContext Unevaluated(
6958 *this, Sema::ExpressionEvaluationContext::Unevaluated);
6960 // For a method call, check the 'this' conversion here too. DR1391 doesn't
6961 // require that, but this check should never result in a hard error, and
6962 // overload resolution is permitted to sidestep instantiations.
6963 if (HasThisConversion && !cast<CXXMethodDecl>(FD)->isStatic() &&
6964 !ObjectType.isNull()) {
6965 unsigned ConvIdx = PO == OverloadCandidateParamOrder::Reversed ? 1 : 0;
6966 Conversions[ConvIdx] = TryObjectArgumentInitialization(
6967 *this, CandidateSet.getLocation(), ObjectType, ObjectClassification,
6968 Method, ActingContext);
6969 if (Conversions[ConvIdx].isBad())
6973 for (unsigned I = 0, N = std::min(ParamTypes.size(), Args.size()); I != N;
6975 QualType ParamType = ParamTypes[I];
6976 if (!ParamType->isDependentType()) {
6977 unsigned ConvIdx = PO == OverloadCandidateParamOrder::Reversed
6979 : (ThisConversions + I);
6980 Conversions[ConvIdx]
6981 = TryCopyInitialization(*this, Args[I], ParamType,
6982 SuppressUserConversions,
6983 /*InOverloadResolution=*/true,
6984 /*AllowObjCWritebackConversion=*/
6985 getLangOpts().ObjCAutoRefCount,
6987 if (Conversions[ConvIdx].isBad())
6995 /// Determine whether this is an allowable conversion from the result
6996 /// of an explicit conversion operator to the expected type, per C++
6997 /// [over.match.conv]p1 and [over.match.ref]p1.
6999 /// \param ConvType The return type of the conversion function.
7001 /// \param ToType The type we are converting to.
7003 /// \param AllowObjCPointerConversion Allow a conversion from one
7004 /// Objective-C pointer to another.
7006 /// \returns true if the conversion is allowable, false otherwise.
7007 static bool isAllowableExplicitConversion(Sema &S,
7008 QualType ConvType, QualType ToType,
7009 bool AllowObjCPointerConversion) {
7010 QualType ToNonRefType = ToType.getNonReferenceType();
7012 // Easy case: the types are the same.
7013 if (S.Context.hasSameUnqualifiedType(ConvType, ToNonRefType))
7016 // Allow qualification conversions.
7017 bool ObjCLifetimeConversion;
7018 if (S.IsQualificationConversion(ConvType, ToNonRefType, /*CStyle*/false,
7019 ObjCLifetimeConversion))
7022 // If we're not allowed to consider Objective-C pointer conversions,
7024 if (!AllowObjCPointerConversion)
7027 // Is this an Objective-C pointer conversion?
7028 bool IncompatibleObjC = false;
7029 QualType ConvertedType;
7030 return S.isObjCPointerConversion(ConvType, ToNonRefType, ConvertedType,
7034 /// AddConversionCandidate - Add a C++ conversion function as a
7035 /// candidate in the candidate set (C++ [over.match.conv],
7036 /// C++ [over.match.copy]). From is the expression we're converting from,
7037 /// and ToType is the type that we're eventually trying to convert to
7038 /// (which may or may not be the same type as the type that the
7039 /// conversion function produces).
7040 void Sema::AddConversionCandidate(
7041 CXXConversionDecl *Conversion, DeclAccessPair FoundDecl,
7042 CXXRecordDecl *ActingContext, Expr *From, QualType ToType,
7043 OverloadCandidateSet &CandidateSet, bool AllowObjCConversionOnExplicit,
7044 bool AllowExplicit, bool AllowResultConversion) {
7045 assert(!Conversion->getDescribedFunctionTemplate() &&
7046 "Conversion function templates use AddTemplateConversionCandidate");
7047 QualType ConvType = Conversion->getConversionType().getNonReferenceType();
7048 if (!CandidateSet.isNewCandidate(Conversion))
7051 // If the conversion function has an undeduced return type, trigger its
7053 if (getLangOpts().CPlusPlus14 && ConvType->isUndeducedType()) {
7054 if (DeduceReturnType(Conversion, From->getExprLoc()))
7056 ConvType = Conversion->getConversionType().getNonReferenceType();
7059 // If we don't allow any conversion of the result type, ignore conversion
7060 // functions that don't convert to exactly (possibly cv-qualified) T.
7061 if (!AllowResultConversion &&
7062 !Context.hasSameUnqualifiedType(Conversion->getConversionType(), ToType))
7065 // Per C++ [over.match.conv]p1, [over.match.ref]p1, an explicit conversion
7066 // operator is only a candidate if its return type is the target type or
7067 // can be converted to the target type with a qualification conversion.
7068 if (Conversion->isExplicit() &&
7069 !isAllowableExplicitConversion(*this, ConvType, ToType,
7070 AllowObjCConversionOnExplicit))
7073 // Overload resolution is always an unevaluated context.
7074 EnterExpressionEvaluationContext Unevaluated(
7075 *this, Sema::ExpressionEvaluationContext::Unevaluated);
7077 // Add this candidate
7078 OverloadCandidate &Candidate = CandidateSet.addCandidate(1);
7079 Candidate.FoundDecl = FoundDecl;
7080 Candidate.Function = Conversion;
7081 Candidate.IsSurrogate = false;
7082 Candidate.IgnoreObjectArgument = false;
7083 Candidate.FinalConversion.setAsIdentityConversion();
7084 Candidate.FinalConversion.setFromType(ConvType);
7085 Candidate.FinalConversion.setAllToTypes(ToType);
7086 Candidate.Viable = true;
7087 Candidate.ExplicitCallArguments = 1;
7089 // C++ [over.match.funcs]p4:
7090 // For conversion functions, the function is considered to be a member of
7091 // the class of the implicit implied object argument for the purpose of
7092 // defining the type of the implicit object parameter.
7094 // Determine the implicit conversion sequence for the implicit
7095 // object parameter.
7096 QualType ImplicitParamType = From->getType();
7097 if (const PointerType *FromPtrType = ImplicitParamType->getAs<PointerType>())
7098 ImplicitParamType = FromPtrType->getPointeeType();
7099 CXXRecordDecl *ConversionContext
7100 = cast<CXXRecordDecl>(ImplicitParamType->castAs<RecordType>()->getDecl());
7102 Candidate.Conversions[0] = TryObjectArgumentInitialization(
7103 *this, CandidateSet.getLocation(), From->getType(),
7104 From->Classify(Context), Conversion, ConversionContext);
7106 if (Candidate.Conversions[0].isBad()) {
7107 Candidate.Viable = false;
7108 Candidate.FailureKind = ovl_fail_bad_conversion;
7112 // We won't go through a user-defined type conversion function to convert a
7113 // derived to base as such conversions are given Conversion Rank. They only
7114 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user]
7116 = Context.getCanonicalType(From->getType().getUnqualifiedType());
7117 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType();
7118 if (FromCanon == ToCanon ||
7119 IsDerivedFrom(CandidateSet.getLocation(), FromCanon, ToCanon)) {
7120 Candidate.Viable = false;
7121 Candidate.FailureKind = ovl_fail_trivial_conversion;
7125 // To determine what the conversion from the result of calling the
7126 // conversion function to the type we're eventually trying to
7127 // convert to (ToType), we need to synthesize a call to the
7128 // conversion function and attempt copy initialization from it. This
7129 // makes sure that we get the right semantics with respect to
7130 // lvalues/rvalues and the type. Fortunately, we can allocate this
7131 // call on the stack and we don't need its arguments to be
7133 DeclRefExpr ConversionRef(Context, Conversion, false, Conversion->getType(),
7134 VK_LValue, From->getBeginLoc());
7135 ImplicitCastExpr ConversionFn(ImplicitCastExpr::OnStack,
7136 Context.getPointerType(Conversion->getType()),
7137 CK_FunctionToPointerDecay,
7138 &ConversionRef, VK_RValue);
7140 QualType ConversionType = Conversion->getConversionType();
7141 if (!isCompleteType(From->getBeginLoc(), ConversionType)) {
7142 Candidate.Viable = false;
7143 Candidate.FailureKind = ovl_fail_bad_final_conversion;
7147 ExprValueKind VK = Expr::getValueKindForType(ConversionType);
7149 // Note that it is safe to allocate CallExpr on the stack here because
7150 // there are 0 arguments (i.e., nothing is allocated using ASTContext's
7152 QualType CallResultType = ConversionType.getNonLValueExprType(Context);
7154 alignas(CallExpr) char Buffer[sizeof(CallExpr) + sizeof(Stmt *)];
7155 CallExpr *TheTemporaryCall = CallExpr::CreateTemporary(
7156 Buffer, &ConversionFn, CallResultType, VK, From->getBeginLoc());
7158 ImplicitConversionSequence ICS =
7159 TryCopyInitialization(*this, TheTemporaryCall, ToType,
7160 /*SuppressUserConversions=*/true,
7161 /*InOverloadResolution=*/false,
7162 /*AllowObjCWritebackConversion=*/false);
7164 switch (ICS.getKind()) {
7165 case ImplicitConversionSequence::StandardConversion:
7166 Candidate.FinalConversion = ICS.Standard;
7168 // C++ [over.ics.user]p3:
7169 // If the user-defined conversion is specified by a specialization of a
7170 // conversion function template, the second standard conversion sequence
7171 // shall have exact match rank.
7172 if (Conversion->getPrimaryTemplate() &&
7173 GetConversionRank(ICS.Standard.Second) != ICR_Exact_Match) {
7174 Candidate.Viable = false;
7175 Candidate.FailureKind = ovl_fail_final_conversion_not_exact;
7179 // C++0x [dcl.init.ref]p5:
7180 // In the second case, if the reference is an rvalue reference and
7181 // the second standard conversion sequence of the user-defined
7182 // conversion sequence includes an lvalue-to-rvalue conversion, the
7183 // program is ill-formed.
7184 if (ToType->isRValueReferenceType() &&
7185 ICS.Standard.First == ICK_Lvalue_To_Rvalue) {
7186 Candidate.Viable = false;
7187 Candidate.FailureKind = ovl_fail_bad_final_conversion;
7192 case ImplicitConversionSequence::BadConversion:
7193 Candidate.Viable = false;
7194 Candidate.FailureKind = ovl_fail_bad_final_conversion;
7199 "Can only end up with a standard conversion sequence or failure");
7202 if (!AllowExplicit && Conversion->getExplicitSpecifier().getKind() !=
7203 ExplicitSpecKind::ResolvedFalse) {
7204 Candidate.Viable = false;
7205 Candidate.FailureKind = ovl_fail_explicit_resolved;
7209 if (EnableIfAttr *FailedAttr = CheckEnableIf(Conversion, None)) {
7210 Candidate.Viable = false;
7211 Candidate.FailureKind = ovl_fail_enable_if;
7212 Candidate.DeductionFailure.Data = FailedAttr;
7216 if (Conversion->isMultiVersion() && Conversion->hasAttr<TargetAttr>() &&
7217 !Conversion->getAttr<TargetAttr>()->isDefaultVersion()) {
7218 Candidate.Viable = false;
7219 Candidate.FailureKind = ovl_non_default_multiversion_function;
7223 /// Adds a conversion function template specialization
7224 /// candidate to the overload set, using template argument deduction
7225 /// to deduce the template arguments of the conversion function
7226 /// template from the type that we are converting to (C++
7227 /// [temp.deduct.conv]).
7228 void Sema::AddTemplateConversionCandidate(
7229 FunctionTemplateDecl *FunctionTemplate, DeclAccessPair FoundDecl,
7230 CXXRecordDecl *ActingDC, Expr *From, QualType ToType,
7231 OverloadCandidateSet &CandidateSet, bool AllowObjCConversionOnExplicit,
7232 bool AllowExplicit, bool AllowResultConversion) {
7233 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) &&
7234 "Only conversion function templates permitted here");
7236 if (!CandidateSet.isNewCandidate(FunctionTemplate))
7239 TemplateDeductionInfo Info(CandidateSet.getLocation());
7240 CXXConversionDecl *Specialization = nullptr;
7241 if (TemplateDeductionResult Result
7242 = DeduceTemplateArguments(FunctionTemplate, ToType,
7243 Specialization, Info)) {
7244 OverloadCandidate &Candidate = CandidateSet.addCandidate();
7245 Candidate.FoundDecl = FoundDecl;
7246 Candidate.Function = FunctionTemplate->getTemplatedDecl();
7247 Candidate.Viable = false;
7248 Candidate.FailureKind = ovl_fail_bad_deduction;
7249 Candidate.IsSurrogate = false;
7250 Candidate.IgnoreObjectArgument = false;
7251 Candidate.ExplicitCallArguments = 1;
7252 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result,
7257 // Add the conversion function template specialization produced by
7258 // template argument deduction as a candidate.
7259 assert(Specialization && "Missing function template specialization?");
7260 AddConversionCandidate(Specialization, FoundDecl, ActingDC, From, ToType,
7261 CandidateSet, AllowObjCConversionOnExplicit,
7262 AllowExplicit, AllowResultConversion);
7265 /// AddSurrogateCandidate - Adds a "surrogate" candidate function that
7266 /// converts the given @c Object to a function pointer via the
7267 /// conversion function @c Conversion, and then attempts to call it
7268 /// with the given arguments (C++ [over.call.object]p2-4). Proto is
7269 /// the type of function that we'll eventually be calling.
7270 void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion,
7271 DeclAccessPair FoundDecl,
7272 CXXRecordDecl *ActingContext,
7273 const FunctionProtoType *Proto,
7275 ArrayRef<Expr *> Args,
7276 OverloadCandidateSet& CandidateSet) {
7277 if (!CandidateSet.isNewCandidate(Conversion))
7280 // Overload resolution is always an unevaluated context.
7281 EnterExpressionEvaluationContext Unevaluated(
7282 *this, Sema::ExpressionEvaluationContext::Unevaluated);
7284 OverloadCandidate &Candidate = CandidateSet.addCandidate(Args.size() + 1);
7285 Candidate.FoundDecl = FoundDecl;
7286 Candidate.Function = nullptr;
7287 Candidate.Surrogate = Conversion;
7288 Candidate.Viable = true;
7289 Candidate.IsSurrogate = true;
7290 Candidate.IgnoreObjectArgument = false;
7291 Candidate.ExplicitCallArguments = Args.size();
7293 // Determine the implicit conversion sequence for the implicit
7294 // object parameter.
7295 ImplicitConversionSequence ObjectInit = TryObjectArgumentInitialization(
7296 *this, CandidateSet.getLocation(), Object->getType(),
7297 Object->Classify(Context), Conversion, ActingContext);
7298 if (ObjectInit.isBad()) {
7299 Candidate.Viable = false;
7300 Candidate.FailureKind = ovl_fail_bad_conversion;
7301 Candidate.Conversions[0] = ObjectInit;
7305 // The first conversion is actually a user-defined conversion whose
7306 // first conversion is ObjectInit's standard conversion (which is
7307 // effectively a reference binding). Record it as such.
7308 Candidate.Conversions[0].setUserDefined();
7309 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard;
7310 Candidate.Conversions[0].UserDefined.EllipsisConversion = false;
7311 Candidate.Conversions[0].UserDefined.HadMultipleCandidates = false;
7312 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion;
7313 Candidate.Conversions[0].UserDefined.FoundConversionFunction = FoundDecl;
7314 Candidate.Conversions[0].UserDefined.After
7315 = Candidate.Conversions[0].UserDefined.Before;
7316 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion();
7319 unsigned NumParams = Proto->getNumParams();
7321 // (C++ 13.3.2p2): A candidate function having fewer than m
7322 // parameters is viable only if it has an ellipsis in its parameter
7324 if (Args.size() > NumParams && !Proto->isVariadic()) {
7325 Candidate.Viable = false;
7326 Candidate.FailureKind = ovl_fail_too_many_arguments;
7330 // Function types don't have any default arguments, so just check if
7331 // we have enough arguments.
7332 if (Args.size() < NumParams) {
7333 // Not enough arguments.
7334 Candidate.Viable = false;
7335 Candidate.FailureKind = ovl_fail_too_few_arguments;
7339 // Determine the implicit conversion sequences for each of the
7341 for (unsigned ArgIdx = 0, N = Args.size(); ArgIdx != N; ++ArgIdx) {
7342 if (ArgIdx < NumParams) {
7343 // (C++ 13.3.2p3): for F to be a viable function, there shall
7344 // exist for each argument an implicit conversion sequence
7345 // (13.3.3.1) that converts that argument to the corresponding
7347 QualType ParamType = Proto->getParamType(ArgIdx);
7348 Candidate.Conversions[ArgIdx + 1]
7349 = TryCopyInitialization(*this, Args[ArgIdx], ParamType,
7350 /*SuppressUserConversions=*/false,
7351 /*InOverloadResolution=*/false,
7352 /*AllowObjCWritebackConversion=*/
7353 getLangOpts().ObjCAutoRefCount);
7354 if (Candidate.Conversions[ArgIdx + 1].isBad()) {
7355 Candidate.Viable = false;
7356 Candidate.FailureKind = ovl_fail_bad_conversion;
7360 // (C++ 13.3.2p2): For the purposes of overload resolution, any
7361 // argument for which there is no corresponding parameter is
7362 // considered to ""match the ellipsis" (C+ 13.3.3.1.3).
7363 Candidate.Conversions[ArgIdx + 1].setEllipsis();
7367 if (EnableIfAttr *FailedAttr = CheckEnableIf(Conversion, None)) {
7368 Candidate.Viable = false;
7369 Candidate.FailureKind = ovl_fail_enable_if;
7370 Candidate.DeductionFailure.Data = FailedAttr;
7375 /// Add all of the non-member operator function declarations in the given
7376 /// function set to the overload candidate set.
7377 void Sema::AddNonMemberOperatorCandidates(
7378 const UnresolvedSetImpl &Fns, ArrayRef<Expr *> Args,
7379 OverloadCandidateSet &CandidateSet,
7380 TemplateArgumentListInfo *ExplicitTemplateArgs) {
7381 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) {
7382 NamedDecl *D = F.getDecl()->getUnderlyingDecl();
7383 ArrayRef<Expr *> FunctionArgs = Args;
7385 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D);
7387 FunTmpl ? FunTmpl->getTemplatedDecl() : cast<FunctionDecl>(D);
7389 // Don't consider rewritten functions if we're not rewriting.
7390 if (!CandidateSet.getRewriteInfo().isAcceptableCandidate(FD))
7393 assert(!isa<CXXMethodDecl>(FD) &&
7394 "unqualified operator lookup found a member function");
7397 AddTemplateOverloadCandidate(FunTmpl, F.getPair(), ExplicitTemplateArgs,
7398 FunctionArgs, CandidateSet);
7399 if (CandidateSet.getRewriteInfo().shouldAddReversed(Context, FD))
7400 AddTemplateOverloadCandidate(
7401 FunTmpl, F.getPair(), ExplicitTemplateArgs,
7402 {FunctionArgs[1], FunctionArgs[0]}, CandidateSet, false, false,
7403 true, ADLCallKind::NotADL, OverloadCandidateParamOrder::Reversed);
7405 if (ExplicitTemplateArgs)
7407 AddOverloadCandidate(FD, F.getPair(), FunctionArgs, CandidateSet);
7408 if (CandidateSet.getRewriteInfo().shouldAddReversed(Context, FD))
7409 AddOverloadCandidate(FD, F.getPair(),
7410 {FunctionArgs[1], FunctionArgs[0]}, CandidateSet,
7411 false, false, true, false, ADLCallKind::NotADL,
7412 None, OverloadCandidateParamOrder::Reversed);
7417 /// Add overload candidates for overloaded operators that are
7418 /// member functions.
7420 /// Add the overloaded operator candidates that are member functions
7421 /// for the operator Op that was used in an operator expression such
7422 /// as "x Op y". , Args/NumArgs provides the operator arguments, and
7423 /// CandidateSet will store the added overload candidates. (C++
7424 /// [over.match.oper]).
7425 void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op,
7426 SourceLocation OpLoc,
7427 ArrayRef<Expr *> Args,
7428 OverloadCandidateSet &CandidateSet,
7429 OverloadCandidateParamOrder PO) {
7430 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op);
7432 // C++ [over.match.oper]p3:
7433 // For a unary operator @ with an operand of a type whose
7434 // cv-unqualified version is T1, and for a binary operator @ with
7435 // a left operand of a type whose cv-unqualified version is T1 and
7436 // a right operand of a type whose cv-unqualified version is T2,
7437 // three sets of candidate functions, designated member
7438 // candidates, non-member candidates and built-in candidates, are
7439 // constructed as follows:
7440 QualType T1 = Args[0]->getType();
7442 // -- If T1 is a complete class type or a class currently being
7443 // defined, the set of member candidates is the result of the
7444 // qualified lookup of T1::operator@ (13.3.1.1.1); otherwise,
7445 // the set of member candidates is empty.
7446 if (const RecordType *T1Rec = T1->getAs<RecordType>()) {
7447 // Complete the type if it can be completed.
7448 if (!isCompleteType(OpLoc, T1) && !T1Rec->isBeingDefined())
7450 // If the type is neither complete nor being defined, bail out now.
7451 if (!T1Rec->getDecl()->getDefinition())
7454 LookupResult Operators(*this, OpName, OpLoc, LookupOrdinaryName);
7455 LookupQualifiedName(Operators, T1Rec->getDecl());
7456 Operators.suppressDiagnostics();
7458 for (LookupResult::iterator Oper = Operators.begin(),
7459 OperEnd = Operators.end();
7462 AddMethodCandidate(Oper.getPair(), Args[0]->getType(),
7463 Args[0]->Classify(Context), Args.slice(1),
7464 CandidateSet, /*SuppressUserConversion=*/false, PO);
7468 /// AddBuiltinCandidate - Add a candidate for a built-in
7469 /// operator. ResultTy and ParamTys are the result and parameter types
7470 /// of the built-in candidate, respectively. Args and NumArgs are the
7471 /// arguments being passed to the candidate. IsAssignmentOperator
7472 /// should be true when this built-in candidate is an assignment
7473 /// operator. NumContextualBoolArguments is the number of arguments
7474 /// (at the beginning of the argument list) that will be contextually
7475 /// converted to bool.
7476 void Sema::AddBuiltinCandidate(QualType *ParamTys, ArrayRef<Expr *> Args,
7477 OverloadCandidateSet& CandidateSet,
7478 bool IsAssignmentOperator,
7479 unsigned NumContextualBoolArguments) {
7480 // Overload resolution is always an unevaluated context.
7481 EnterExpressionEvaluationContext Unevaluated(
7482 *this, Sema::ExpressionEvaluationContext::Unevaluated);
7484 // Add this candidate
7485 OverloadCandidate &Candidate = CandidateSet.addCandidate(Args.size());
7486 Candidate.FoundDecl = DeclAccessPair::make(nullptr, AS_none);
7487 Candidate.Function = nullptr;
7488 Candidate.IsSurrogate = false;
7489 Candidate.IgnoreObjectArgument = false;
7490 std::copy(ParamTys, ParamTys + Args.size(), Candidate.BuiltinParamTypes);
7492 // Determine the implicit conversion sequences for each of the
7494 Candidate.Viable = true;
7495 Candidate.ExplicitCallArguments = Args.size();
7496 for (unsigned ArgIdx = 0, N = Args.size(); ArgIdx != N; ++ArgIdx) {
7497 // C++ [over.match.oper]p4:
7498 // For the built-in assignment operators, conversions of the
7499 // left operand are restricted as follows:
7500 // -- no temporaries are introduced to hold the left operand, and
7501 // -- no user-defined conversions are applied to the left
7502 // operand to achieve a type match with the left-most
7503 // parameter of a built-in candidate.
7505 // We block these conversions by turning off user-defined
7506 // conversions, since that is the only way that initialization of
7507 // a reference to a non-class type can occur from something that
7508 // is not of the same type.
7509 if (ArgIdx < NumContextualBoolArguments) {
7510 assert(ParamTys[ArgIdx] == Context.BoolTy &&
7511 "Contextual conversion to bool requires bool type");
7512 Candidate.Conversions[ArgIdx]
7513 = TryContextuallyConvertToBool(*this, Args[ArgIdx]);
7515 Candidate.Conversions[ArgIdx]
7516 = TryCopyInitialization(*this, Args[ArgIdx], ParamTys[ArgIdx],
7517 ArgIdx == 0 && IsAssignmentOperator,
7518 /*InOverloadResolution=*/false,
7519 /*AllowObjCWritebackConversion=*/
7520 getLangOpts().ObjCAutoRefCount);
7522 if (Candidate.Conversions[ArgIdx].isBad()) {
7523 Candidate.Viable = false;
7524 Candidate.FailureKind = ovl_fail_bad_conversion;
7532 /// BuiltinCandidateTypeSet - A set of types that will be used for the
7533 /// candidate operator functions for built-in operators (C++
7534 /// [over.built]). The types are separated into pointer types and
7535 /// enumeration types.
7536 class BuiltinCandidateTypeSet {
7537 /// TypeSet - A set of types.
7538 typedef llvm::SetVector<QualType, SmallVector<QualType, 8>,
7539 llvm::SmallPtrSet<QualType, 8>> TypeSet;
7541 /// PointerTypes - The set of pointer types that will be used in the
7542 /// built-in candidates.
7543 TypeSet PointerTypes;
7545 /// MemberPointerTypes - The set of member pointer types that will be
7546 /// used in the built-in candidates.
7547 TypeSet MemberPointerTypes;
7549 /// EnumerationTypes - The set of enumeration types that will be
7550 /// used in the built-in candidates.
7551 TypeSet EnumerationTypes;
7553 /// The set of vector types that will be used in the built-in
7555 TypeSet VectorTypes;
7557 /// A flag indicating non-record types are viable candidates
7558 bool HasNonRecordTypes;
7560 /// A flag indicating whether either arithmetic or enumeration types
7561 /// were present in the candidate set.
7562 bool HasArithmeticOrEnumeralTypes;
7564 /// A flag indicating whether the nullptr type was present in the
7566 bool HasNullPtrType;
7568 /// Sema - The semantic analysis instance where we are building the
7569 /// candidate type set.
7572 /// Context - The AST context in which we will build the type sets.
7573 ASTContext &Context;
7575 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty,
7576 const Qualifiers &VisibleQuals);
7577 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty);
7580 /// iterator - Iterates through the types that are part of the set.
7581 typedef TypeSet::iterator iterator;
7583 BuiltinCandidateTypeSet(Sema &SemaRef)
7584 : HasNonRecordTypes(false),
7585 HasArithmeticOrEnumeralTypes(false),
7586 HasNullPtrType(false),
7588 Context(SemaRef.Context) { }
7590 void AddTypesConvertedFrom(QualType Ty,
7592 bool AllowUserConversions,
7593 bool AllowExplicitConversions,
7594 const Qualifiers &VisibleTypeConversionsQuals);
7596 /// pointer_begin - First pointer type found;
7597 iterator pointer_begin() { return PointerTypes.begin(); }
7599 /// pointer_end - Past the last pointer type found;
7600 iterator pointer_end() { return PointerTypes.end(); }
7602 /// member_pointer_begin - First member pointer type found;
7603 iterator member_pointer_begin() { return MemberPointerTypes.begin(); }
7605 /// member_pointer_end - Past the last member pointer type found;
7606 iterator member_pointer_end() { return MemberPointerTypes.end(); }
7608 /// enumeration_begin - First enumeration type found;
7609 iterator enumeration_begin() { return EnumerationTypes.begin(); }
7611 /// enumeration_end - Past the last enumeration type found;
7612 iterator enumeration_end() { return EnumerationTypes.end(); }
7614 iterator vector_begin() { return VectorTypes.begin(); }
7615 iterator vector_end() { return VectorTypes.end(); }
7617 bool hasNonRecordTypes() { return HasNonRecordTypes; }
7618 bool hasArithmeticOrEnumeralTypes() { return HasArithmeticOrEnumeralTypes; }
7619 bool hasNullPtrType() const { return HasNullPtrType; }
7622 } // end anonymous namespace
7624 /// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to
7625 /// the set of pointer types along with any more-qualified variants of
7626 /// that type. For example, if @p Ty is "int const *", this routine
7627 /// will add "int const *", "int const volatile *", "int const
7628 /// restrict *", and "int const volatile restrict *" to the set of
7629 /// pointer types. Returns true if the add of @p Ty itself succeeded,
7630 /// false otherwise.
7632 /// FIXME: what to do about extended qualifiers?
7634 BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty,
7635 const Qualifiers &VisibleQuals) {
7637 // Insert this type.
7638 if (!PointerTypes.insert(Ty))
7642 const PointerType *PointerTy = Ty->getAs<PointerType>();
7643 bool buildObjCPtr = false;
7645 const ObjCObjectPointerType *PTy = Ty->castAs<ObjCObjectPointerType>();
7646 PointeeTy = PTy->getPointeeType();
7647 buildObjCPtr = true;
7649 PointeeTy = PointerTy->getPointeeType();
7652 // Don't add qualified variants of arrays. For one, they're not allowed
7653 // (the qualifier would sink to the element type), and for another, the
7654 // only overload situation where it matters is subscript or pointer +- int,
7655 // and those shouldn't have qualifier variants anyway.
7656 if (PointeeTy->isArrayType())
7659 unsigned BaseCVR = PointeeTy.getCVRQualifiers();
7660 bool hasVolatile = VisibleQuals.hasVolatile();
7661 bool hasRestrict = VisibleQuals.hasRestrict();
7663 // Iterate through all strict supersets of BaseCVR.
7664 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) {
7665 if ((CVR | BaseCVR) != CVR) continue;
7666 // Skip over volatile if no volatile found anywhere in the types.
7667 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue;
7669 // Skip over restrict if no restrict found anywhere in the types, or if
7670 // the type cannot be restrict-qualified.
7671 if ((CVR & Qualifiers::Restrict) &&
7673 (!(PointeeTy->isAnyPointerType() || PointeeTy->isReferenceType()))))
7676 // Build qualified pointee type.
7677 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR);
7679 // Build qualified pointer type.
7680 QualType QPointerTy;
7682 QPointerTy = Context.getPointerType(QPointeeTy);
7684 QPointerTy = Context.getObjCObjectPointerType(QPointeeTy);
7686 // Insert qualified pointer type.
7687 PointerTypes.insert(QPointerTy);
7693 /// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty
7694 /// to the set of pointer types along with any more-qualified variants of
7695 /// that type. For example, if @p Ty is "int const *", this routine
7696 /// will add "int const *", "int const volatile *", "int const
7697 /// restrict *", and "int const volatile restrict *" to the set of
7698 /// pointer types. Returns true if the add of @p Ty itself succeeded,
7699 /// false otherwise.
7701 /// FIXME: what to do about extended qualifiers?
7703 BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants(
7705 // Insert this type.
7706 if (!MemberPointerTypes.insert(Ty))
7709 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>();
7710 assert(PointerTy && "type was not a member pointer type!");
7712 QualType PointeeTy = PointerTy->getPointeeType();
7713 // Don't add qualified variants of arrays. For one, they're not allowed
7714 // (the qualifier would sink to the element type), and for another, the
7715 // only overload situation where it matters is subscript or pointer +- int,
7716 // and those shouldn't have qualifier variants anyway.
7717 if (PointeeTy->isArrayType())
7719 const Type *ClassTy = PointerTy->getClass();
7721 // Iterate through all strict supersets of the pointee type's CVR
7723 unsigned BaseCVR = PointeeTy.getCVRQualifiers();
7724 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) {
7725 if ((CVR | BaseCVR) != CVR) continue;
7727 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR);
7728 MemberPointerTypes.insert(
7729 Context.getMemberPointerType(QPointeeTy, ClassTy));
7735 /// AddTypesConvertedFrom - Add each of the types to which the type @p
7736 /// Ty can be implicit converted to the given set of @p Types. We're
7737 /// primarily interested in pointer types and enumeration types. We also
7738 /// take member pointer types, for the conditional operator.
7739 /// AllowUserConversions is true if we should look at the conversion
7740 /// functions of a class type, and AllowExplicitConversions if we
7741 /// should also include the explicit conversion functions of a class
7744 BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty,
7746 bool AllowUserConversions,
7747 bool AllowExplicitConversions,
7748 const Qualifiers &VisibleQuals) {
7749 // Only deal with canonical types.
7750 Ty = Context.getCanonicalType(Ty);
7752 // Look through reference types; they aren't part of the type of an
7753 // expression for the purposes of conversions.
7754 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>())
7755 Ty = RefTy->getPointeeType();
7757 // If we're dealing with an array type, decay to the pointer.
7758 if (Ty->isArrayType())
7759 Ty = SemaRef.Context.getArrayDecayedType(Ty);
7761 // Otherwise, we don't care about qualifiers on the type.
7762 Ty = Ty.getLocalUnqualifiedType();
7764 // Flag if we ever add a non-record type.
7765 const RecordType *TyRec = Ty->getAs<RecordType>();
7766 HasNonRecordTypes = HasNonRecordTypes || !TyRec;
7768 // Flag if we encounter an arithmetic type.
7769 HasArithmeticOrEnumeralTypes =
7770 HasArithmeticOrEnumeralTypes || Ty->isArithmeticType();
7772 if (Ty->isObjCIdType() || Ty->isObjCClassType())
7773 PointerTypes.insert(Ty);
7774 else if (Ty->getAs<PointerType>() || Ty->getAs<ObjCObjectPointerType>()) {
7775 // Insert our type, and its more-qualified variants, into the set
7777 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals))
7779 } else if (Ty->isMemberPointerType()) {
7780 // Member pointers are far easier, since the pointee can't be converted.
7781 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty))
7783 } else if (Ty->isEnumeralType()) {
7784 HasArithmeticOrEnumeralTypes = true;
7785 EnumerationTypes.insert(Ty);
7786 } else if (Ty->isVectorType()) {
7787 // We treat vector types as arithmetic types in many contexts as an
7789 HasArithmeticOrEnumeralTypes = true;
7790 VectorTypes.insert(Ty);
7791 } else if (Ty->isNullPtrType()) {
7792 HasNullPtrType = true;
7793 } else if (AllowUserConversions && TyRec) {
7794 // No conversion functions in incomplete types.
7795 if (!SemaRef.isCompleteType(Loc, Ty))
7798 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl());
7799 for (NamedDecl *D : ClassDecl->getVisibleConversionFunctions()) {
7800 if (isa<UsingShadowDecl>(D))
7801 D = cast<UsingShadowDecl>(D)->getTargetDecl();
7803 // Skip conversion function templates; they don't tell us anything
7804 // about which builtin types we can convert to.
7805 if (isa<FunctionTemplateDecl>(D))
7808 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D);
7809 if (AllowExplicitConversions || !Conv->isExplicit()) {
7810 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false,
7816 /// Helper function for adjusting address spaces for the pointer or reference
7817 /// operands of builtin operators depending on the argument.
7818 static QualType AdjustAddressSpaceForBuiltinOperandType(Sema &S, QualType T,
7820 return S.Context.getAddrSpaceQualType(T, Arg->getType().getAddressSpace());
7823 /// Helper function for AddBuiltinOperatorCandidates() that adds
7824 /// the volatile- and non-volatile-qualified assignment operators for the
7825 /// given type to the candidate set.
7826 static void AddBuiltinAssignmentOperatorCandidates(Sema &S,
7828 ArrayRef<Expr *> Args,
7829 OverloadCandidateSet &CandidateSet) {
7830 QualType ParamTypes[2];
7832 // T& operator=(T&, T)
7833 ParamTypes[0] = S.Context.getLValueReferenceType(
7834 AdjustAddressSpaceForBuiltinOperandType(S, T, Args[0]));
7836 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
7837 /*IsAssignmentOperator=*/true);
7839 if (!S.Context.getCanonicalType(T).isVolatileQualified()) {
7840 // volatile T& operator=(volatile T&, T)
7841 ParamTypes[0] = S.Context.getLValueReferenceType(
7842 AdjustAddressSpaceForBuiltinOperandType(S, S.Context.getVolatileType(T),
7845 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
7846 /*IsAssignmentOperator=*/true);
7850 /// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers,
7851 /// if any, found in visible type conversion functions found in ArgExpr's type.
7852 static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) {
7854 const RecordType *TyRec;
7855 if (const MemberPointerType *RHSMPType =
7856 ArgExpr->getType()->getAs<MemberPointerType>())
7857 TyRec = RHSMPType->getClass()->getAs<RecordType>();
7859 TyRec = ArgExpr->getType()->getAs<RecordType>();
7861 // Just to be safe, assume the worst case.
7862 VRQuals.addVolatile();
7863 VRQuals.addRestrict();
7867 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl());
7868 if (!ClassDecl->hasDefinition())
7871 for (NamedDecl *D : ClassDecl->getVisibleConversionFunctions()) {
7872 if (isa<UsingShadowDecl>(D))
7873 D = cast<UsingShadowDecl>(D)->getTargetDecl();
7874 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) {
7875 QualType CanTy = Context.getCanonicalType(Conv->getConversionType());
7876 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>())
7877 CanTy = ResTypeRef->getPointeeType();
7878 // Need to go down the pointer/mempointer chain and add qualifiers
7882 if (CanTy.isRestrictQualified())
7883 VRQuals.addRestrict();
7884 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>())
7885 CanTy = ResTypePtr->getPointeeType();
7886 else if (const MemberPointerType *ResTypeMPtr =
7887 CanTy->getAs<MemberPointerType>())
7888 CanTy = ResTypeMPtr->getPointeeType();
7891 if (CanTy.isVolatileQualified())
7892 VRQuals.addVolatile();
7893 if (VRQuals.hasRestrict() && VRQuals.hasVolatile())
7903 /// Helper class to manage the addition of builtin operator overload
7904 /// candidates. It provides shared state and utility methods used throughout
7905 /// the process, as well as a helper method to add each group of builtin
7906 /// operator overloads from the standard to a candidate set.
7907 class BuiltinOperatorOverloadBuilder {
7908 // Common instance state available to all overload candidate addition methods.
7910 ArrayRef<Expr *> Args;
7911 Qualifiers VisibleTypeConversionsQuals;
7912 bool HasArithmeticOrEnumeralCandidateType;
7913 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes;
7914 OverloadCandidateSet &CandidateSet;
7916 static constexpr int ArithmeticTypesCap = 24;
7917 SmallVector<CanQualType, ArithmeticTypesCap> ArithmeticTypes;
7919 // Define some indices used to iterate over the arithmetic types in
7920 // ArithmeticTypes. The "promoted arithmetic types" are the arithmetic
7921 // types are that preserved by promotion (C++ [over.built]p2).
7922 unsigned FirstIntegralType,
7924 unsigned FirstPromotedIntegralType,
7925 LastPromotedIntegralType;
7926 unsigned FirstPromotedArithmeticType,
7927 LastPromotedArithmeticType;
7928 unsigned NumArithmeticTypes;
7930 void InitArithmeticTypes() {
7931 // Start of promoted types.
7932 FirstPromotedArithmeticType = 0;
7933 ArithmeticTypes.push_back(S.Context.FloatTy);
7934 ArithmeticTypes.push_back(S.Context.DoubleTy);
7935 ArithmeticTypes.push_back(S.Context.LongDoubleTy);
7936 if (S.Context.getTargetInfo().hasFloat128Type())
7937 ArithmeticTypes.push_back(S.Context.Float128Ty);
7939 // Start of integral types.
7940 FirstIntegralType = ArithmeticTypes.size();
7941 FirstPromotedIntegralType = ArithmeticTypes.size();
7942 ArithmeticTypes.push_back(S.Context.IntTy);
7943 ArithmeticTypes.push_back(S.Context.LongTy);
7944 ArithmeticTypes.push_back(S.Context.LongLongTy);
7945 if (S.Context.getTargetInfo().hasInt128Type())
7946 ArithmeticTypes.push_back(S.Context.Int128Ty);
7947 ArithmeticTypes.push_back(S.Context.UnsignedIntTy);
7948 ArithmeticTypes.push_back(S.Context.UnsignedLongTy);
7949 ArithmeticTypes.push_back(S.Context.UnsignedLongLongTy);
7950 if (S.Context.getTargetInfo().hasInt128Type())
7951 ArithmeticTypes.push_back(S.Context.UnsignedInt128Ty);
7952 LastPromotedIntegralType = ArithmeticTypes.size();
7953 LastPromotedArithmeticType = ArithmeticTypes.size();
7954 // End of promoted types.
7956 ArithmeticTypes.push_back(S.Context.BoolTy);
7957 ArithmeticTypes.push_back(S.Context.CharTy);
7958 ArithmeticTypes.push_back(S.Context.WCharTy);
7959 if (S.Context.getLangOpts().Char8)
7960 ArithmeticTypes.push_back(S.Context.Char8Ty);
7961 ArithmeticTypes.push_back(S.Context.Char16Ty);
7962 ArithmeticTypes.push_back(S.Context.Char32Ty);
7963 ArithmeticTypes.push_back(S.Context.SignedCharTy);
7964 ArithmeticTypes.push_back(S.Context.ShortTy);
7965 ArithmeticTypes.push_back(S.Context.UnsignedCharTy);
7966 ArithmeticTypes.push_back(S.Context.UnsignedShortTy);
7967 LastIntegralType = ArithmeticTypes.size();
7968 NumArithmeticTypes = ArithmeticTypes.size();
7969 // End of integral types.
7970 // FIXME: What about complex? What about half?
7972 assert(ArithmeticTypes.size() <= ArithmeticTypesCap &&
7973 "Enough inline storage for all arithmetic types.");
7976 /// Helper method to factor out the common pattern of adding overloads
7977 /// for '++' and '--' builtin operators.
7978 void addPlusPlusMinusMinusStyleOverloads(QualType CandidateTy,
7981 QualType ParamTypes[2] = {
7982 S.Context.getLValueReferenceType(CandidateTy),
7986 // Non-volatile version.
7987 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
7989 // Use a heuristic to reduce number of builtin candidates in the set:
7990 // add volatile version only if there are conversions to a volatile type.
7993 S.Context.getLValueReferenceType(
7994 S.Context.getVolatileType(CandidateTy));
7995 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
7998 // Add restrict version only if there are conversions to a restrict type
7999 // and our candidate type is a non-restrict-qualified pointer.
8000 if (HasRestrict && CandidateTy->isAnyPointerType() &&
8001 !CandidateTy.isRestrictQualified()) {
8003 = S.Context.getLValueReferenceType(
8004 S.Context.getCVRQualifiedType(CandidateTy, Qualifiers::Restrict));
8005 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8009 = S.Context.getLValueReferenceType(
8010 S.Context.getCVRQualifiedType(CandidateTy,
8011 (Qualifiers::Volatile |
8012 Qualifiers::Restrict)));
8013 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8020 BuiltinOperatorOverloadBuilder(
8021 Sema &S, ArrayRef<Expr *> Args,
8022 Qualifiers VisibleTypeConversionsQuals,
8023 bool HasArithmeticOrEnumeralCandidateType,
8024 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes,
8025 OverloadCandidateSet &CandidateSet)
8027 VisibleTypeConversionsQuals(VisibleTypeConversionsQuals),
8028 HasArithmeticOrEnumeralCandidateType(
8029 HasArithmeticOrEnumeralCandidateType),
8030 CandidateTypes(CandidateTypes),
8031 CandidateSet(CandidateSet) {
8033 InitArithmeticTypes();
8036 // Increment is deprecated for bool since C++17.
8038 // C++ [over.built]p3:
8040 // For every pair (T, VQ), where T is an arithmetic type other
8041 // than bool, and VQ is either volatile or empty, there exist
8042 // candidate operator functions of the form
8044 // VQ T& operator++(VQ T&);
8045 // T operator++(VQ T&, int);
8047 // C++ [over.built]p4:
8049 // For every pair (T, VQ), where T is an arithmetic type other
8050 // than bool, and VQ is either volatile or empty, there exist
8051 // candidate operator functions of the form
8053 // VQ T& operator--(VQ T&);
8054 // T operator--(VQ T&, int);
8055 void addPlusPlusMinusMinusArithmeticOverloads(OverloadedOperatorKind Op) {
8056 if (!HasArithmeticOrEnumeralCandidateType)
8059 for (unsigned Arith = 0; Arith < NumArithmeticTypes; ++Arith) {
8060 const auto TypeOfT = ArithmeticTypes[Arith];
8061 if (TypeOfT == S.Context.BoolTy) {
8062 if (Op == OO_MinusMinus)
8064 if (Op == OO_PlusPlus && S.getLangOpts().CPlusPlus17)
8067 addPlusPlusMinusMinusStyleOverloads(
8069 VisibleTypeConversionsQuals.hasVolatile(),
8070 VisibleTypeConversionsQuals.hasRestrict());
8074 // C++ [over.built]p5:
8076 // For every pair (T, VQ), where T is a cv-qualified or
8077 // cv-unqualified object type, and VQ is either volatile or
8078 // empty, there exist candidate operator functions of the form
8080 // T*VQ& operator++(T*VQ&);
8081 // T*VQ& operator--(T*VQ&);
8082 // T* operator++(T*VQ&, int);
8083 // T* operator--(T*VQ&, int);
8084 void addPlusPlusMinusMinusPointerOverloads() {
8085 for (BuiltinCandidateTypeSet::iterator
8086 Ptr = CandidateTypes[0].pointer_begin(),
8087 PtrEnd = CandidateTypes[0].pointer_end();
8088 Ptr != PtrEnd; ++Ptr) {
8089 // Skip pointer types that aren't pointers to object types.
8090 if (!(*Ptr)->getPointeeType()->isObjectType())
8093 addPlusPlusMinusMinusStyleOverloads(*Ptr,
8094 (!(*Ptr).isVolatileQualified() &&
8095 VisibleTypeConversionsQuals.hasVolatile()),
8096 (!(*Ptr).isRestrictQualified() &&
8097 VisibleTypeConversionsQuals.hasRestrict()));
8101 // C++ [over.built]p6:
8102 // For every cv-qualified or cv-unqualified object type T, there
8103 // exist candidate operator functions of the form
8105 // T& operator*(T*);
8107 // C++ [over.built]p7:
8108 // For every function type T that does not have cv-qualifiers or a
8109 // ref-qualifier, there exist candidate operator functions of the form
8110 // T& operator*(T*);
8111 void addUnaryStarPointerOverloads() {
8112 for (BuiltinCandidateTypeSet::iterator
8113 Ptr = CandidateTypes[0].pointer_begin(),
8114 PtrEnd = CandidateTypes[0].pointer_end();
8115 Ptr != PtrEnd; ++Ptr) {
8116 QualType ParamTy = *Ptr;
8117 QualType PointeeTy = ParamTy->getPointeeType();
8118 if (!PointeeTy->isObjectType() && !PointeeTy->isFunctionType())
8121 if (const FunctionProtoType *Proto =PointeeTy->getAs<FunctionProtoType>())
8122 if (Proto->getMethodQuals() || Proto->getRefQualifier())
8125 S.AddBuiltinCandidate(&ParamTy, Args, CandidateSet);
8129 // C++ [over.built]p9:
8130 // For every promoted arithmetic type T, there exist candidate
8131 // operator functions of the form
8135 void addUnaryPlusOrMinusArithmeticOverloads() {
8136 if (!HasArithmeticOrEnumeralCandidateType)
8139 for (unsigned Arith = FirstPromotedArithmeticType;
8140 Arith < LastPromotedArithmeticType; ++Arith) {
8141 QualType ArithTy = ArithmeticTypes[Arith];
8142 S.AddBuiltinCandidate(&ArithTy, Args, CandidateSet);
8145 // Extension: We also add these operators for vector types.
8146 for (BuiltinCandidateTypeSet::iterator
8147 Vec = CandidateTypes[0].vector_begin(),
8148 VecEnd = CandidateTypes[0].vector_end();
8149 Vec != VecEnd; ++Vec) {
8150 QualType VecTy = *Vec;
8151 S.AddBuiltinCandidate(&VecTy, Args, CandidateSet);
8155 // C++ [over.built]p8:
8156 // For every type T, there exist candidate operator functions of
8159 // T* operator+(T*);
8160 void addUnaryPlusPointerOverloads() {
8161 for (BuiltinCandidateTypeSet::iterator
8162 Ptr = CandidateTypes[0].pointer_begin(),
8163 PtrEnd = CandidateTypes[0].pointer_end();
8164 Ptr != PtrEnd; ++Ptr) {
8165 QualType ParamTy = *Ptr;
8166 S.AddBuiltinCandidate(&ParamTy, Args, CandidateSet);
8170 // C++ [over.built]p10:
8171 // For every promoted integral type T, there exist candidate
8172 // operator functions of the form
8175 void addUnaryTildePromotedIntegralOverloads() {
8176 if (!HasArithmeticOrEnumeralCandidateType)
8179 for (unsigned Int = FirstPromotedIntegralType;
8180 Int < LastPromotedIntegralType; ++Int) {
8181 QualType IntTy = ArithmeticTypes[Int];
8182 S.AddBuiltinCandidate(&IntTy, Args, CandidateSet);
8185 // Extension: We also add this operator for vector types.
8186 for (BuiltinCandidateTypeSet::iterator
8187 Vec = CandidateTypes[0].vector_begin(),
8188 VecEnd = CandidateTypes[0].vector_end();
8189 Vec != VecEnd; ++Vec) {
8190 QualType VecTy = *Vec;
8191 S.AddBuiltinCandidate(&VecTy, Args, CandidateSet);
8195 // C++ [over.match.oper]p16:
8196 // For every pointer to member type T or type std::nullptr_t, there
8197 // exist candidate operator functions of the form
8199 // bool operator==(T,T);
8200 // bool operator!=(T,T);
8201 void addEqualEqualOrNotEqualMemberPointerOrNullptrOverloads() {
8202 /// Set of (canonical) types that we've already handled.
8203 llvm::SmallPtrSet<QualType, 8> AddedTypes;
8205 for (unsigned ArgIdx = 0, N = Args.size(); ArgIdx != N; ++ArgIdx) {
8206 for (BuiltinCandidateTypeSet::iterator
8207 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(),
8208 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end();
8209 MemPtr != MemPtrEnd;
8211 // Don't add the same builtin candidate twice.
8212 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr)).second)
8215 QualType ParamTypes[2] = { *MemPtr, *MemPtr };
8216 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8219 if (CandidateTypes[ArgIdx].hasNullPtrType()) {
8220 CanQualType NullPtrTy = S.Context.getCanonicalType(S.Context.NullPtrTy);
8221 if (AddedTypes.insert(NullPtrTy).second) {
8222 QualType ParamTypes[2] = { NullPtrTy, NullPtrTy };
8223 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8229 // C++ [over.built]p15:
8231 // For every T, where T is an enumeration type or a pointer type,
8232 // there exist candidate operator functions of the form
8234 // bool operator<(T, T);
8235 // bool operator>(T, T);
8236 // bool operator<=(T, T);
8237 // bool operator>=(T, T);
8238 // bool operator==(T, T);
8239 // bool operator!=(T, T);
8240 // R operator<=>(T, T)
8241 void addGenericBinaryPointerOrEnumeralOverloads() {
8242 // C++ [over.match.oper]p3:
8243 // [...]the built-in candidates include all of the candidate operator
8244 // functions defined in 13.6 that, compared to the given operator, [...]
8245 // do not have the same parameter-type-list as any non-template non-member
8248 // Note that in practice, this only affects enumeration types because there
8249 // aren't any built-in candidates of record type, and a user-defined operator
8250 // must have an operand of record or enumeration type. Also, the only other
8251 // overloaded operator with enumeration arguments, operator=,
8252 // cannot be overloaded for enumeration types, so this is the only place
8253 // where we must suppress candidates like this.
8254 llvm::DenseSet<std::pair<CanQualType, CanQualType> >
8255 UserDefinedBinaryOperators;
8257 for (unsigned ArgIdx = 0, N = Args.size(); ArgIdx != N; ++ArgIdx) {
8258 if (CandidateTypes[ArgIdx].enumeration_begin() !=
8259 CandidateTypes[ArgIdx].enumeration_end()) {
8260 for (OverloadCandidateSet::iterator C = CandidateSet.begin(),
8261 CEnd = CandidateSet.end();
8263 if (!C->Viable || !C->Function || C->Function->getNumParams() != 2)
8266 if (C->Function->isFunctionTemplateSpecialization())
8269 // We interpret "same parameter-type-list" as applying to the
8270 // "synthesized candidate, with the order of the two parameters
8271 // reversed", not to the original function.
8272 bool Reversed = C->RewriteKind & CRK_Reversed;
8273 QualType FirstParamType = C->Function->getParamDecl(Reversed ? 1 : 0)
8275 .getUnqualifiedType();
8276 QualType SecondParamType = C->Function->getParamDecl(Reversed ? 0 : 1)
8278 .getUnqualifiedType();
8280 // Skip if either parameter isn't of enumeral type.
8281 if (!FirstParamType->isEnumeralType() ||
8282 !SecondParamType->isEnumeralType())
8285 // Add this operator to the set of known user-defined operators.
8286 UserDefinedBinaryOperators.insert(
8287 std::make_pair(S.Context.getCanonicalType(FirstParamType),
8288 S.Context.getCanonicalType(SecondParamType)));
8293 /// Set of (canonical) types that we've already handled.
8294 llvm::SmallPtrSet<QualType, 8> AddedTypes;
8296 for (unsigned ArgIdx = 0, N = Args.size(); ArgIdx != N; ++ArgIdx) {
8297 for (BuiltinCandidateTypeSet::iterator
8298 Ptr = CandidateTypes[ArgIdx].pointer_begin(),
8299 PtrEnd = CandidateTypes[ArgIdx].pointer_end();
8300 Ptr != PtrEnd; ++Ptr) {
8301 // Don't add the same builtin candidate twice.
8302 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr)).second)
8305 QualType ParamTypes[2] = { *Ptr, *Ptr };
8306 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8308 for (BuiltinCandidateTypeSet::iterator
8309 Enum = CandidateTypes[ArgIdx].enumeration_begin(),
8310 EnumEnd = CandidateTypes[ArgIdx].enumeration_end();
8311 Enum != EnumEnd; ++Enum) {
8312 CanQualType CanonType = S.Context.getCanonicalType(*Enum);
8314 // Don't add the same builtin candidate twice, or if a user defined
8315 // candidate exists.
8316 if (!AddedTypes.insert(CanonType).second ||
8317 UserDefinedBinaryOperators.count(std::make_pair(CanonType,
8320 QualType ParamTypes[2] = { *Enum, *Enum };
8321 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8326 // C++ [over.built]p13:
8328 // For every cv-qualified or cv-unqualified object type T
8329 // there exist candidate operator functions of the form
8331 // T* operator+(T*, ptrdiff_t);
8332 // T& operator[](T*, ptrdiff_t); [BELOW]
8333 // T* operator-(T*, ptrdiff_t);
8334 // T* operator+(ptrdiff_t, T*);
8335 // T& operator[](ptrdiff_t, T*); [BELOW]
8337 // C++ [over.built]p14:
8339 // For every T, where T is a pointer to object type, there
8340 // exist candidate operator functions of the form
8342 // ptrdiff_t operator-(T, T);
8343 void addBinaryPlusOrMinusPointerOverloads(OverloadedOperatorKind Op) {
8344 /// Set of (canonical) types that we've already handled.
8345 llvm::SmallPtrSet<QualType, 8> AddedTypes;
8347 for (int Arg = 0; Arg < 2; ++Arg) {
8348 QualType AsymmetricParamTypes[2] = {
8349 S.Context.getPointerDiffType(),
8350 S.Context.getPointerDiffType(),
8352 for (BuiltinCandidateTypeSet::iterator
8353 Ptr = CandidateTypes[Arg].pointer_begin(),
8354 PtrEnd = CandidateTypes[Arg].pointer_end();
8355 Ptr != PtrEnd; ++Ptr) {
8356 QualType PointeeTy = (*Ptr)->getPointeeType();
8357 if (!PointeeTy->isObjectType())
8360 AsymmetricParamTypes[Arg] = *Ptr;
8361 if (Arg == 0 || Op == OO_Plus) {
8362 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t)
8363 // T* operator+(ptrdiff_t, T*);
8364 S.AddBuiltinCandidate(AsymmetricParamTypes, Args, CandidateSet);
8366 if (Op == OO_Minus) {
8367 // ptrdiff_t operator-(T, T);
8368 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr)).second)
8371 QualType ParamTypes[2] = { *Ptr, *Ptr };
8372 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8378 // C++ [over.built]p12:
8380 // For every pair of promoted arithmetic types L and R, there
8381 // exist candidate operator functions of the form
8383 // LR operator*(L, R);
8384 // LR operator/(L, R);
8385 // LR operator+(L, R);
8386 // LR operator-(L, R);
8387 // bool operator<(L, R);
8388 // bool operator>(L, R);
8389 // bool operator<=(L, R);
8390 // bool operator>=(L, R);
8391 // bool operator==(L, R);
8392 // bool operator!=(L, R);
8394 // where LR is the result of the usual arithmetic conversions
8395 // between types L and R.
8397 // C++ [over.built]p24:
8399 // For every pair of promoted arithmetic types L and R, there exist
8400 // candidate operator functions of the form
8402 // LR operator?(bool, L, R);
8404 // where LR is the result of the usual arithmetic conversions
8405 // between types L and R.
8406 // Our candidates ignore the first parameter.
8407 void addGenericBinaryArithmeticOverloads() {
8408 if (!HasArithmeticOrEnumeralCandidateType)
8411 for (unsigned Left = FirstPromotedArithmeticType;
8412 Left < LastPromotedArithmeticType; ++Left) {
8413 for (unsigned Right = FirstPromotedArithmeticType;
8414 Right < LastPromotedArithmeticType; ++Right) {
8415 QualType LandR[2] = { ArithmeticTypes[Left],
8416 ArithmeticTypes[Right] };
8417 S.AddBuiltinCandidate(LandR, Args, CandidateSet);
8421 // Extension: Add the binary operators ==, !=, <, <=, >=, >, *, /, and the
8422 // conditional operator for vector types.
8423 for (BuiltinCandidateTypeSet::iterator
8424 Vec1 = CandidateTypes[0].vector_begin(),
8425 Vec1End = CandidateTypes[0].vector_end();
8426 Vec1 != Vec1End; ++Vec1) {
8427 for (BuiltinCandidateTypeSet::iterator
8428 Vec2 = CandidateTypes[1].vector_begin(),
8429 Vec2End = CandidateTypes[1].vector_end();
8430 Vec2 != Vec2End; ++Vec2) {
8431 QualType LandR[2] = { *Vec1, *Vec2 };
8432 S.AddBuiltinCandidate(LandR, Args, CandidateSet);
8437 // C++2a [over.built]p14:
8439 // For every integral type T there exists a candidate operator function
8442 // std::strong_ordering operator<=>(T, T)
8444 // C++2a [over.built]p15:
8446 // For every pair of floating-point types L and R, there exists a candidate
8447 // operator function of the form
8449 // std::partial_ordering operator<=>(L, R);
8451 // FIXME: The current specification for integral types doesn't play nice with
8452 // the direction of p0946r0, which allows mixed integral and unscoped-enum
8453 // comparisons. Under the current spec this can lead to ambiguity during
8454 // overload resolution. For example:
8456 // enum A : int {a};
8457 // auto x = (a <=> (long)42);
8459 // error: call is ambiguous for arguments 'A' and 'long'.
8460 // note: candidate operator<=>(int, int)
8461 // note: candidate operator<=>(long, long)
8463 // To avoid this error, this function deviates from the specification and adds
8464 // the mixed overloads `operator<=>(L, R)` where L and R are promoted
8465 // arithmetic types (the same as the generic relational overloads).
8467 // For now this function acts as a placeholder.
8468 void addThreeWayArithmeticOverloads() {
8469 addGenericBinaryArithmeticOverloads();
8472 // C++ [over.built]p17:
8474 // For every pair of promoted integral types L and R, there
8475 // exist candidate operator functions of the form
8477 // LR operator%(L, R);
8478 // LR operator&(L, R);
8479 // LR operator^(L, R);
8480 // LR operator|(L, R);
8481 // L operator<<(L, R);
8482 // L operator>>(L, R);
8484 // where LR is the result of the usual arithmetic conversions
8485 // between types L and R.
8486 void addBinaryBitwiseArithmeticOverloads(OverloadedOperatorKind Op) {
8487 if (!HasArithmeticOrEnumeralCandidateType)
8490 for (unsigned Left = FirstPromotedIntegralType;
8491 Left < LastPromotedIntegralType; ++Left) {
8492 for (unsigned Right = FirstPromotedIntegralType;
8493 Right < LastPromotedIntegralType; ++Right) {
8494 QualType LandR[2] = { ArithmeticTypes[Left],
8495 ArithmeticTypes[Right] };
8496 S.AddBuiltinCandidate(LandR, Args, CandidateSet);
8501 // C++ [over.built]p20:
8503 // For every pair (T, VQ), where T is an enumeration or
8504 // pointer to member type and VQ is either volatile or
8505 // empty, there exist candidate operator functions of the form
8507 // VQ T& operator=(VQ T&, T);
8508 void addAssignmentMemberPointerOrEnumeralOverloads() {
8509 /// Set of (canonical) types that we've already handled.
8510 llvm::SmallPtrSet<QualType, 8> AddedTypes;
8512 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) {
8513 for (BuiltinCandidateTypeSet::iterator
8514 Enum = CandidateTypes[ArgIdx].enumeration_begin(),
8515 EnumEnd = CandidateTypes[ArgIdx].enumeration_end();
8516 Enum != EnumEnd; ++Enum) {
8517 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum)).second)
8520 AddBuiltinAssignmentOperatorCandidates(S, *Enum, Args, CandidateSet);
8523 for (BuiltinCandidateTypeSet::iterator
8524 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(),
8525 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end();
8526 MemPtr != MemPtrEnd; ++MemPtr) {
8527 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr)).second)
8530 AddBuiltinAssignmentOperatorCandidates(S, *MemPtr, Args, CandidateSet);
8535 // C++ [over.built]p19:
8537 // For every pair (T, VQ), where T is any type and VQ is either
8538 // volatile or empty, there exist candidate operator functions
8541 // T*VQ& operator=(T*VQ&, T*);
8543 // C++ [over.built]p21:
8545 // For every pair (T, VQ), where T is a cv-qualified or
8546 // cv-unqualified object type and VQ is either volatile or
8547 // empty, there exist candidate operator functions of the form
8549 // T*VQ& operator+=(T*VQ&, ptrdiff_t);
8550 // T*VQ& operator-=(T*VQ&, ptrdiff_t);
8551 void addAssignmentPointerOverloads(bool isEqualOp) {
8552 /// Set of (canonical) types that we've already handled.
8553 llvm::SmallPtrSet<QualType, 8> AddedTypes;
8555 for (BuiltinCandidateTypeSet::iterator
8556 Ptr = CandidateTypes[0].pointer_begin(),
8557 PtrEnd = CandidateTypes[0].pointer_end();
8558 Ptr != PtrEnd; ++Ptr) {
8559 // If this is operator=, keep track of the builtin candidates we added.
8561 AddedTypes.insert(S.Context.getCanonicalType(*Ptr));
8562 else if (!(*Ptr)->getPointeeType()->isObjectType())
8565 // non-volatile version
8566 QualType ParamTypes[2] = {
8567 S.Context.getLValueReferenceType(*Ptr),
8568 isEqualOp ? *Ptr : S.Context.getPointerDiffType(),
8570 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8571 /*IsAssignmentOperator=*/ isEqualOp);
8573 bool NeedVolatile = !(*Ptr).isVolatileQualified() &&
8574 VisibleTypeConversionsQuals.hasVolatile();
8578 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr));
8579 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8580 /*IsAssignmentOperator=*/isEqualOp);
8583 if (!(*Ptr).isRestrictQualified() &&
8584 VisibleTypeConversionsQuals.hasRestrict()) {
8587 = S.Context.getLValueReferenceType(S.Context.getRestrictType(*Ptr));
8588 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8589 /*IsAssignmentOperator=*/isEqualOp);
8592 // volatile restrict version
8594 = S.Context.getLValueReferenceType(
8595 S.Context.getCVRQualifiedType(*Ptr,
8596 (Qualifiers::Volatile |
8597 Qualifiers::Restrict)));
8598 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8599 /*IsAssignmentOperator=*/isEqualOp);
8605 for (BuiltinCandidateTypeSet::iterator
8606 Ptr = CandidateTypes[1].pointer_begin(),
8607 PtrEnd = CandidateTypes[1].pointer_end();
8608 Ptr != PtrEnd; ++Ptr) {
8609 // Make sure we don't add the same candidate twice.
8610 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr)).second)
8613 QualType ParamTypes[2] = {
8614 S.Context.getLValueReferenceType(*Ptr),
8618 // non-volatile version
8619 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8620 /*IsAssignmentOperator=*/true);
8622 bool NeedVolatile = !(*Ptr).isVolatileQualified() &&
8623 VisibleTypeConversionsQuals.hasVolatile();
8627 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr));
8628 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8629 /*IsAssignmentOperator=*/true);
8632 if (!(*Ptr).isRestrictQualified() &&
8633 VisibleTypeConversionsQuals.hasRestrict()) {
8636 = S.Context.getLValueReferenceType(S.Context.getRestrictType(*Ptr));
8637 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8638 /*IsAssignmentOperator=*/true);
8641 // volatile restrict version
8643 = S.Context.getLValueReferenceType(
8644 S.Context.getCVRQualifiedType(*Ptr,
8645 (Qualifiers::Volatile |
8646 Qualifiers::Restrict)));
8647 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8648 /*IsAssignmentOperator=*/true);
8655 // C++ [over.built]p18:
8657 // For every triple (L, VQ, R), where L is an arithmetic type,
8658 // VQ is either volatile or empty, and R is a promoted
8659 // arithmetic type, there exist candidate operator functions of
8662 // VQ L& operator=(VQ L&, R);
8663 // VQ L& operator*=(VQ L&, R);
8664 // VQ L& operator/=(VQ L&, R);
8665 // VQ L& operator+=(VQ L&, R);
8666 // VQ L& operator-=(VQ L&, R);
8667 void addAssignmentArithmeticOverloads(bool isEqualOp) {
8668 if (!HasArithmeticOrEnumeralCandidateType)
8671 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) {
8672 for (unsigned Right = FirstPromotedArithmeticType;
8673 Right < LastPromotedArithmeticType; ++Right) {
8674 QualType ParamTypes[2];
8675 ParamTypes[1] = ArithmeticTypes[Right];
8676 auto LeftBaseTy = AdjustAddressSpaceForBuiltinOperandType(
8677 S, ArithmeticTypes[Left], Args[0]);
8678 // Add this built-in operator as a candidate (VQ is empty).
8679 ParamTypes[0] = S.Context.getLValueReferenceType(LeftBaseTy);
8680 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8681 /*IsAssignmentOperator=*/isEqualOp);
8683 // Add this built-in operator as a candidate (VQ is 'volatile').
8684 if (VisibleTypeConversionsQuals.hasVolatile()) {
8685 ParamTypes[0] = S.Context.getVolatileType(LeftBaseTy);
8686 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]);
8687 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8688 /*IsAssignmentOperator=*/isEqualOp);
8693 // Extension: Add the binary operators =, +=, -=, *=, /= for vector types.
8694 for (BuiltinCandidateTypeSet::iterator
8695 Vec1 = CandidateTypes[0].vector_begin(),
8696 Vec1End = CandidateTypes[0].vector_end();
8697 Vec1 != Vec1End; ++Vec1) {
8698 for (BuiltinCandidateTypeSet::iterator
8699 Vec2 = CandidateTypes[1].vector_begin(),
8700 Vec2End = CandidateTypes[1].vector_end();
8701 Vec2 != Vec2End; ++Vec2) {
8702 QualType ParamTypes[2];
8703 ParamTypes[1] = *Vec2;
8704 // Add this built-in operator as a candidate (VQ is empty).
8705 ParamTypes[0] = S.Context.getLValueReferenceType(*Vec1);
8706 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8707 /*IsAssignmentOperator=*/isEqualOp);
8709 // Add this built-in operator as a candidate (VQ is 'volatile').
8710 if (VisibleTypeConversionsQuals.hasVolatile()) {
8711 ParamTypes[0] = S.Context.getVolatileType(*Vec1);
8712 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]);
8713 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8714 /*IsAssignmentOperator=*/isEqualOp);
8720 // C++ [over.built]p22:
8722 // For every triple (L, VQ, R), where L is an integral type, VQ
8723 // is either volatile or empty, and R is a promoted integral
8724 // type, there exist candidate operator functions of the form
8726 // VQ L& operator%=(VQ L&, R);
8727 // VQ L& operator<<=(VQ L&, R);
8728 // VQ L& operator>>=(VQ L&, R);
8729 // VQ L& operator&=(VQ L&, R);
8730 // VQ L& operator^=(VQ L&, R);
8731 // VQ L& operator|=(VQ L&, R);
8732 void addAssignmentIntegralOverloads() {
8733 if (!HasArithmeticOrEnumeralCandidateType)
8736 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) {
8737 for (unsigned Right = FirstPromotedIntegralType;
8738 Right < LastPromotedIntegralType; ++Right) {
8739 QualType ParamTypes[2];
8740 ParamTypes[1] = ArithmeticTypes[Right];
8741 auto LeftBaseTy = AdjustAddressSpaceForBuiltinOperandType(
8742 S, ArithmeticTypes[Left], Args[0]);
8743 // Add this built-in operator as a candidate (VQ is empty).
8744 ParamTypes[0] = S.Context.getLValueReferenceType(LeftBaseTy);
8745 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8746 if (VisibleTypeConversionsQuals.hasVolatile()) {
8747 // Add this built-in operator as a candidate (VQ is 'volatile').
8748 ParamTypes[0] = LeftBaseTy;
8749 ParamTypes[0] = S.Context.getVolatileType(ParamTypes[0]);
8750 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]);
8751 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8757 // C++ [over.operator]p23:
8759 // There also exist candidate operator functions of the form
8761 // bool operator!(bool);
8762 // bool operator&&(bool, bool);
8763 // bool operator||(bool, bool);
8764 void addExclaimOverload() {
8765 QualType ParamTy = S.Context.BoolTy;
8766 S.AddBuiltinCandidate(&ParamTy, Args, CandidateSet,
8767 /*IsAssignmentOperator=*/false,
8768 /*NumContextualBoolArguments=*/1);
8770 void addAmpAmpOrPipePipeOverload() {
8771 QualType ParamTypes[2] = { S.Context.BoolTy, S.Context.BoolTy };
8772 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
8773 /*IsAssignmentOperator=*/false,
8774 /*NumContextualBoolArguments=*/2);
8777 // C++ [over.built]p13:
8779 // For every cv-qualified or cv-unqualified object type T there
8780 // exist candidate operator functions of the form
8782 // T* operator+(T*, ptrdiff_t); [ABOVE]
8783 // T& operator[](T*, ptrdiff_t);
8784 // T* operator-(T*, ptrdiff_t); [ABOVE]
8785 // T* operator+(ptrdiff_t, T*); [ABOVE]
8786 // T& operator[](ptrdiff_t, T*);
8787 void addSubscriptOverloads() {
8788 for (BuiltinCandidateTypeSet::iterator
8789 Ptr = CandidateTypes[0].pointer_begin(),
8790 PtrEnd = CandidateTypes[0].pointer_end();
8791 Ptr != PtrEnd; ++Ptr) {
8792 QualType ParamTypes[2] = { *Ptr, S.Context.getPointerDiffType() };
8793 QualType PointeeType = (*Ptr)->getPointeeType();
8794 if (!PointeeType->isObjectType())
8797 // T& operator[](T*, ptrdiff_t)
8798 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8801 for (BuiltinCandidateTypeSet::iterator
8802 Ptr = CandidateTypes[1].pointer_begin(),
8803 PtrEnd = CandidateTypes[1].pointer_end();
8804 Ptr != PtrEnd; ++Ptr) {
8805 QualType ParamTypes[2] = { S.Context.getPointerDiffType(), *Ptr };
8806 QualType PointeeType = (*Ptr)->getPointeeType();
8807 if (!PointeeType->isObjectType())
8810 // T& operator[](ptrdiff_t, T*)
8811 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8815 // C++ [over.built]p11:
8816 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type,
8817 // C1 is the same type as C2 or is a derived class of C2, T is an object
8818 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
8819 // there exist candidate operator functions of the form
8821 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
8823 // where CV12 is the union of CV1 and CV2.
8824 void addArrowStarOverloads() {
8825 for (BuiltinCandidateTypeSet::iterator
8826 Ptr = CandidateTypes[0].pointer_begin(),
8827 PtrEnd = CandidateTypes[0].pointer_end();
8828 Ptr != PtrEnd; ++Ptr) {
8829 QualType C1Ty = (*Ptr);
8831 QualifierCollector Q1;
8832 C1 = QualType(Q1.strip(C1Ty->getPointeeType()), 0);
8833 if (!isa<RecordType>(C1))
8835 // heuristic to reduce number of builtin candidates in the set.
8836 // Add volatile/restrict version only if there are conversions to a
8837 // volatile/restrict type.
8838 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile())
8840 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict())
8842 for (BuiltinCandidateTypeSet::iterator
8843 MemPtr = CandidateTypes[1].member_pointer_begin(),
8844 MemPtrEnd = CandidateTypes[1].member_pointer_end();
8845 MemPtr != MemPtrEnd; ++MemPtr) {
8846 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr);
8847 QualType C2 = QualType(mptr->getClass(), 0);
8848 C2 = C2.getUnqualifiedType();
8849 if (C1 != C2 && !S.IsDerivedFrom(CandidateSet.getLocation(), C1, C2))
8851 QualType ParamTypes[2] = { *Ptr, *MemPtr };
8853 QualType T = mptr->getPointeeType();
8854 if (!VisibleTypeConversionsQuals.hasVolatile() &&
8855 T.isVolatileQualified())
8857 if (!VisibleTypeConversionsQuals.hasRestrict() &&
8858 T.isRestrictQualified())
8860 T = Q1.apply(S.Context, T);
8861 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8866 // Note that we don't consider the first argument, since it has been
8867 // contextually converted to bool long ago. The candidates below are
8868 // therefore added as binary.
8870 // C++ [over.built]p25:
8871 // For every type T, where T is a pointer, pointer-to-member, or scoped
8872 // enumeration type, there exist candidate operator functions of the form
8874 // T operator?(bool, T, T);
8876 void addConditionalOperatorOverloads() {
8877 /// Set of (canonical) types that we've already handled.
8878 llvm::SmallPtrSet<QualType, 8> AddedTypes;
8880 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) {
8881 for (BuiltinCandidateTypeSet::iterator
8882 Ptr = CandidateTypes[ArgIdx].pointer_begin(),
8883 PtrEnd = CandidateTypes[ArgIdx].pointer_end();
8884 Ptr != PtrEnd; ++Ptr) {
8885 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr)).second)
8888 QualType ParamTypes[2] = { *Ptr, *Ptr };
8889 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8892 for (BuiltinCandidateTypeSet::iterator
8893 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(),
8894 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end();
8895 MemPtr != MemPtrEnd; ++MemPtr) {
8896 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr)).second)
8899 QualType ParamTypes[2] = { *MemPtr, *MemPtr };
8900 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8903 if (S.getLangOpts().CPlusPlus11) {
8904 for (BuiltinCandidateTypeSet::iterator
8905 Enum = CandidateTypes[ArgIdx].enumeration_begin(),
8906 EnumEnd = CandidateTypes[ArgIdx].enumeration_end();
8907 Enum != EnumEnd; ++Enum) {
8908 if (!(*Enum)->castAs<EnumType>()->getDecl()->isScoped())
8911 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum)).second)
8914 QualType ParamTypes[2] = { *Enum, *Enum };
8915 S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet);
8922 } // end anonymous namespace
8924 /// AddBuiltinOperatorCandidates - Add the appropriate built-in
8925 /// operator overloads to the candidate set (C++ [over.built]), based
8926 /// on the operator @p Op and the arguments given. For example, if the
8927 /// operator is a binary '+', this routine might add "int
8928 /// operator+(int, int)" to cover integer addition.
8929 void Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op,
8930 SourceLocation OpLoc,
8931 ArrayRef<Expr *> Args,
8932 OverloadCandidateSet &CandidateSet) {
8933 // Find all of the types that the arguments can convert to, but only
8934 // if the operator we're looking at has built-in operator candidates
8935 // that make use of these types. Also record whether we encounter non-record
8936 // candidate types or either arithmetic or enumeral candidate types.
8937 Qualifiers VisibleTypeConversionsQuals;
8938 VisibleTypeConversionsQuals.addConst();
8939 for (unsigned ArgIdx = 0, N = Args.size(); ArgIdx != N; ++ArgIdx)
8940 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]);
8942 bool HasNonRecordCandidateType = false;
8943 bool HasArithmeticOrEnumeralCandidateType = false;
8944 SmallVector<BuiltinCandidateTypeSet, 2> CandidateTypes;
8945 for (unsigned ArgIdx = 0, N = Args.size(); ArgIdx != N; ++ArgIdx) {
8946 CandidateTypes.emplace_back(*this);
8947 CandidateTypes[ArgIdx].AddTypesConvertedFrom(Args[ArgIdx]->getType(),
8950 (Op == OO_Exclaim ||
8953 VisibleTypeConversionsQuals);
8954 HasNonRecordCandidateType = HasNonRecordCandidateType ||
8955 CandidateTypes[ArgIdx].hasNonRecordTypes();
8956 HasArithmeticOrEnumeralCandidateType =
8957 HasArithmeticOrEnumeralCandidateType ||
8958 CandidateTypes[ArgIdx].hasArithmeticOrEnumeralTypes();
8961 // Exit early when no non-record types have been added to the candidate set
8962 // for any of the arguments to the operator.
8964 // We can't exit early for !, ||, or &&, since there we have always have
8965 // 'bool' overloads.
8966 if (!HasNonRecordCandidateType &&
8967 !(Op == OO_Exclaim || Op == OO_AmpAmp || Op == OO_PipePipe))
8970 // Setup an object to manage the common state for building overloads.
8971 BuiltinOperatorOverloadBuilder OpBuilder(*this, Args,
8972 VisibleTypeConversionsQuals,
8973 HasArithmeticOrEnumeralCandidateType,
8974 CandidateTypes, CandidateSet);
8976 // Dispatch over the operation to add in only those overloads which apply.
8979 case NUM_OVERLOADED_OPERATORS:
8980 llvm_unreachable("Expected an overloaded operator");
8985 case OO_Array_Delete:
8988 "Special operators don't use AddBuiltinOperatorCandidates");
8993 // C++ [over.match.oper]p3:
8994 // -- For the operator ',', the unary operator '&', the
8995 // operator '->', or the operator 'co_await', the
8996 // built-in candidates set is empty.
8999 case OO_Plus: // '+' is either unary or binary
9000 if (Args.size() == 1)
9001 OpBuilder.addUnaryPlusPointerOverloads();
9004 case OO_Minus: // '-' is either unary or binary
9005 if (Args.size() == 1) {
9006 OpBuilder.addUnaryPlusOrMinusArithmeticOverloads();
9008 OpBuilder.addBinaryPlusOrMinusPointerOverloads(Op);
9009 OpBuilder.addGenericBinaryArithmeticOverloads();
9013 case OO_Star: // '*' is either unary or binary
9014 if (Args.size() == 1)
9015 OpBuilder.addUnaryStarPointerOverloads();
9017 OpBuilder.addGenericBinaryArithmeticOverloads();
9021 OpBuilder.addGenericBinaryArithmeticOverloads();
9026 OpBuilder.addPlusPlusMinusMinusArithmeticOverloads(Op);
9027 OpBuilder.addPlusPlusMinusMinusPointerOverloads();
9031 case OO_ExclaimEqual:
9032 OpBuilder.addEqualEqualOrNotEqualMemberPointerOrNullptrOverloads();
9038 case OO_GreaterEqual:
9039 OpBuilder.addGenericBinaryPointerOrEnumeralOverloads();
9040 OpBuilder.addGenericBinaryArithmeticOverloads();
9044 OpBuilder.addGenericBinaryPointerOrEnumeralOverloads();
9045 OpBuilder.addThreeWayArithmeticOverloads();
9052 case OO_GreaterGreater:
9053 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op);
9056 case OO_Amp: // '&' is either unary or binary
9057 if (Args.size() == 1)
9058 // C++ [over.match.oper]p3:
9059 // -- For the operator ',', the unary operator '&', or the
9060 // operator '->', the built-in candidates set is empty.
9063 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op);
9067 OpBuilder.addUnaryTildePromotedIntegralOverloads();
9071 OpBuilder.addAssignmentMemberPointerOrEnumeralOverloads();
9076 OpBuilder.addAssignmentPointerOverloads(Op == OO_Equal);
9081 OpBuilder.addAssignmentArithmeticOverloads(Op == OO_Equal);
9084 case OO_PercentEqual:
9085 case OO_LessLessEqual:
9086 case OO_GreaterGreaterEqual:
9090 OpBuilder.addAssignmentIntegralOverloads();
9094 OpBuilder.addExclaimOverload();
9099 OpBuilder.addAmpAmpOrPipePipeOverload();
9103 OpBuilder.addSubscriptOverloads();
9107 OpBuilder.addArrowStarOverloads();
9110 case OO_Conditional:
9111 OpBuilder.addConditionalOperatorOverloads();
9112 OpBuilder.addGenericBinaryArithmeticOverloads();
9117 /// Add function candidates found via argument-dependent lookup
9118 /// to the set of overloading candidates.
9120 /// This routine performs argument-dependent name lookup based on the
9121 /// given function name (which may also be an operator name) and adds
9122 /// all of the overload candidates found by ADL to the overload
9123 /// candidate set (C++ [basic.lookup.argdep]).
9125 Sema::AddArgumentDependentLookupCandidates(DeclarationName Name,
9127 ArrayRef<Expr *> Args,
9128 TemplateArgumentListInfo *ExplicitTemplateArgs,
9129 OverloadCandidateSet& CandidateSet,
9130 bool PartialOverloading) {
9133 // FIXME: This approach for uniquing ADL results (and removing
9134 // redundant candidates from the set) relies on pointer-equality,
9135 // which means we need to key off the canonical decl. However,
9136 // always going back to the canonical decl might not get us the
9137 // right set of default arguments. What default arguments are
9138 // we supposed to consider on ADL candidates, anyway?
9140 // FIXME: Pass in the explicit template arguments?
9141 ArgumentDependentLookup(Name, Loc, Args, Fns);
9143 // Erase all of the candidates we already knew about.
9144 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(),
9145 CandEnd = CandidateSet.end();
9146 Cand != CandEnd; ++Cand)
9147 if (Cand->Function) {
9148 Fns.erase(Cand->Function);
9149 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate())
9153 // For each of the ADL candidates we found, add it to the overload
9155 for (ADLResult::iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) {
9156 DeclAccessPair FoundDecl = DeclAccessPair::make(*I, AS_none);
9158 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) {
9159 if (ExplicitTemplateArgs)
9162 AddOverloadCandidate(FD, FoundDecl, Args, CandidateSet,
9163 /*SuppressUserConversions=*/false, PartialOverloading,
9164 /*AllowExplicit*/ true,
9165 /*AllowExplicitConversions*/ false,
9166 ADLCallKind::UsesADL);
9168 AddTemplateOverloadCandidate(
9169 cast<FunctionTemplateDecl>(*I), FoundDecl, ExplicitTemplateArgs, Args,
9171 /*SuppressUserConversions=*/false, PartialOverloading,
9172 /*AllowExplicit*/true, ADLCallKind::UsesADL);
9178 enum class Comparison { Equal, Better, Worse };
9181 /// Compares the enable_if attributes of two FunctionDecls, for the purposes of
9182 /// overload resolution.
9184 /// Cand1's set of enable_if attributes are said to be "better" than Cand2's iff
9185 /// Cand1's first N enable_if attributes have precisely the same conditions as
9186 /// Cand2's first N enable_if attributes (where N = the number of enable_if
9187 /// attributes on Cand2), and Cand1 has more than N enable_if attributes.
9189 /// Note that you can have a pair of candidates such that Cand1's enable_if
9190 /// attributes are worse than Cand2's, and Cand2's enable_if attributes are
9191 /// worse than Cand1's.
9192 static Comparison compareEnableIfAttrs(const Sema &S, const FunctionDecl *Cand1,
9193 const FunctionDecl *Cand2) {
9194 // Common case: One (or both) decls don't have enable_if attrs.
9195 bool Cand1Attr = Cand1->hasAttr<EnableIfAttr>();
9196 bool Cand2Attr = Cand2->hasAttr<EnableIfAttr>();
9197 if (!Cand1Attr || !Cand2Attr) {
9198 if (Cand1Attr == Cand2Attr)
9199 return Comparison::Equal;
9200 return Cand1Attr ? Comparison::Better : Comparison::Worse;
9203 auto Cand1Attrs = Cand1->specific_attrs<EnableIfAttr>();
9204 auto Cand2Attrs = Cand2->specific_attrs<EnableIfAttr>();
9206 llvm::FoldingSetNodeID Cand1ID, Cand2ID;
9207 for (auto Pair : zip_longest(Cand1Attrs, Cand2Attrs)) {
9208 Optional<EnableIfAttr *> Cand1A = std::get<0>(Pair);
9209 Optional<EnableIfAttr *> Cand2A = std::get<1>(Pair);
9211 // It's impossible for Cand1 to be better than (or equal to) Cand2 if Cand1
9212 // has fewer enable_if attributes than Cand2, and vice versa.
9214 return Comparison::Worse;
9216 return Comparison::Better;
9221 (*Cand1A)->getCond()->Profile(Cand1ID, S.getASTContext(), true);
9222 (*Cand2A)->getCond()->Profile(Cand2ID, S.getASTContext(), true);
9223 if (Cand1ID != Cand2ID)
9224 return Comparison::Worse;
9227 return Comparison::Equal;
9230 static bool isBetterMultiversionCandidate(const OverloadCandidate &Cand1,
9231 const OverloadCandidate &Cand2) {
9232 if (!Cand1.Function || !Cand1.Function->isMultiVersion() || !Cand2.Function ||
9233 !Cand2.Function->isMultiVersion())
9236 // If Cand1 is invalid, it cannot be a better match, if Cand2 is invalid, this
9237 // is obviously better.
9238 if (Cand1.Function->isInvalidDecl()) return false;
9239 if (Cand2.Function->isInvalidDecl()) return true;
9241 // If this is a cpu_dispatch/cpu_specific multiversion situation, prefer
9242 // cpu_dispatch, else arbitrarily based on the identifiers.
9243 bool Cand1CPUDisp = Cand1.Function->hasAttr<CPUDispatchAttr>();
9244 bool Cand2CPUDisp = Cand2.Function->hasAttr<CPUDispatchAttr>();
9245 const auto *Cand1CPUSpec = Cand1.Function->getAttr<CPUSpecificAttr>();
9246 const auto *Cand2CPUSpec = Cand2.Function->getAttr<CPUSpecificAttr>();
9248 if (!Cand1CPUDisp && !Cand2CPUDisp && !Cand1CPUSpec && !Cand2CPUSpec)
9251 if (Cand1CPUDisp && !Cand2CPUDisp)
9253 if (Cand2CPUDisp && !Cand1CPUDisp)
9256 if (Cand1CPUSpec && Cand2CPUSpec) {
9257 if (Cand1CPUSpec->cpus_size() != Cand2CPUSpec->cpus_size())
9258 return Cand1CPUSpec->cpus_size() < Cand2CPUSpec->cpus_size();
9260 std::pair<CPUSpecificAttr::cpus_iterator, CPUSpecificAttr::cpus_iterator>
9261 FirstDiff = std::mismatch(
9262 Cand1CPUSpec->cpus_begin(), Cand1CPUSpec->cpus_end(),
9263 Cand2CPUSpec->cpus_begin(),
9264 [](const IdentifierInfo *LHS, const IdentifierInfo *RHS) {
9265 return LHS->getName() == RHS->getName();
9268 assert(FirstDiff.first != Cand1CPUSpec->cpus_end() &&
9269 "Two different cpu-specific versions should not have the same "
9270 "identifier list, otherwise they'd be the same decl!");
9271 return (*FirstDiff.first)->getName() < (*FirstDiff.second)->getName();
9273 llvm_unreachable("No way to get here unless both had cpu_dispatch");
9276 /// isBetterOverloadCandidate - Determines whether the first overload
9277 /// candidate is a better candidate than the second (C++ 13.3.3p1).
9278 bool clang::isBetterOverloadCandidate(
9279 Sema &S, const OverloadCandidate &Cand1, const OverloadCandidate &Cand2,
9280 SourceLocation Loc, OverloadCandidateSet::CandidateSetKind Kind) {
9281 // Define viable functions to be better candidates than non-viable
9284 return Cand1.Viable;
9285 else if (!Cand1.Viable)
9288 // C++ [over.match.best]p1:
9290 // -- if F is a static member function, ICS1(F) is defined such
9291 // that ICS1(F) is neither better nor worse than ICS1(G) for
9292 // any function G, and, symmetrically, ICS1(G) is neither
9293 // better nor worse than ICS1(F).
9294 unsigned StartArg = 0;
9295 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument)
9298 auto IsIllFormedConversion = [&](const ImplicitConversionSequence &ICS) {
9299 // We don't allow incompatible pointer conversions in C++.
9300 if (!S.getLangOpts().CPlusPlus)
9301 return ICS.isStandard() &&
9302 ICS.Standard.Second == ICK_Incompatible_Pointer_Conversion;
9304 // The only ill-formed conversion we allow in C++ is the string literal to
9305 // char* conversion, which is only considered ill-formed after C++11.
9306 return S.getLangOpts().CPlusPlus11 && !S.getLangOpts().WritableStrings &&
9307 hasDeprecatedStringLiteralToCharPtrConversion(ICS);
9310 // Define functions that don't require ill-formed conversions for a given
9311 // argument to be better candidates than functions that do.
9312 unsigned NumArgs = Cand1.Conversions.size();
9313 assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch");
9314 bool HasBetterConversion = false;
9315 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) {
9316 bool Cand1Bad = IsIllFormedConversion(Cand1.Conversions[ArgIdx]);
9317 bool Cand2Bad = IsIllFormedConversion(Cand2.Conversions[ArgIdx]);
9318 if (Cand1Bad != Cand2Bad) {
9321 HasBetterConversion = true;
9325 if (HasBetterConversion)
9328 // C++ [over.match.best]p1:
9329 // A viable function F1 is defined to be a better function than another
9330 // viable function F2 if for all arguments i, ICSi(F1) is not a worse
9331 // conversion sequence than ICSi(F2), and then...
9332 bool HasWorseConversion = false;
9333 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) {
9334 switch (CompareImplicitConversionSequences(S, Loc,
9335 Cand1.Conversions[ArgIdx],
9336 Cand2.Conversions[ArgIdx])) {
9337 case ImplicitConversionSequence::Better:
9338 // Cand1 has a better conversion sequence.
9339 HasBetterConversion = true;
9342 case ImplicitConversionSequence::Worse:
9343 if (Cand1.Function && Cand1.Function == Cand2.Function &&
9344 (Cand2.RewriteKind & CRK_Reversed) != 0) {
9345 // Work around large-scale breakage caused by considering reversed
9346 // forms of operator== in C++20:
9348 // When comparing a function against its reversed form, if we have a
9349 // better conversion for one argument and a worse conversion for the
9350 // other, we prefer the non-reversed form.
9352 // This prevents a conversion function from being considered ambiguous
9353 // with its own reversed form in various where it's only incidentally
9356 // We diagnose this as an extension from CreateOverloadedBinOp.
9357 HasWorseConversion = true;
9361 // Cand1 can't be better than Cand2.
9364 case ImplicitConversionSequence::Indistinguishable:
9370 // -- for some argument j, ICSj(F1) is a better conversion sequence than
9371 // ICSj(F2), or, if not that,
9372 if (HasBetterConversion)
9374 if (HasWorseConversion)
9377 // -- the context is an initialization by user-defined conversion
9378 // (see 8.5, 13.3.1.5) and the standard conversion sequence
9379 // from the return type of F1 to the destination type (i.e.,
9380 // the type of the entity being initialized) is a better
9381 // conversion sequence than the standard conversion sequence
9382 // from the return type of F2 to the destination type.
9383 if (Kind == OverloadCandidateSet::CSK_InitByUserDefinedConversion &&
9384 Cand1.Function && Cand2.Function &&
9385 isa<CXXConversionDecl>(Cand1.Function) &&
9386 isa<CXXConversionDecl>(Cand2.Function)) {
9387 // First check whether we prefer one of the conversion functions over the
9388 // other. This only distinguishes the results in non-standard, extension
9389 // cases such as the conversion from a lambda closure type to a function
9390 // pointer or block.
9391 ImplicitConversionSequence::CompareKind Result =
9392 compareConversionFunctions(S, Cand1.Function, Cand2.Function);
9393 if (Result == ImplicitConversionSequence::Indistinguishable)
9394 Result = CompareStandardConversionSequences(S, Loc,
9395 Cand1.FinalConversion,
9396 Cand2.FinalConversion);
9398 if (Result != ImplicitConversionSequence::Indistinguishable)
9399 return Result == ImplicitConversionSequence::Better;
9401 // FIXME: Compare kind of reference binding if conversion functions
9402 // convert to a reference type used in direct reference binding, per
9403 // C++14 [over.match.best]p1 section 2 bullet 3.
9406 // FIXME: Work around a defect in the C++17 guaranteed copy elision wording,
9407 // as combined with the resolution to CWG issue 243.
9409 // When the context is initialization by constructor ([over.match.ctor] or
9410 // either phase of [over.match.list]), a constructor is preferred over
9411 // a conversion function.
9412 if (Kind == OverloadCandidateSet::CSK_InitByConstructor && NumArgs == 1 &&
9413 Cand1.Function && Cand2.Function &&
9414 isa<CXXConstructorDecl>(Cand1.Function) !=
9415 isa<CXXConstructorDecl>(Cand2.Function))
9416 return isa<CXXConstructorDecl>(Cand1.Function);
9418 // -- F1 is a non-template function and F2 is a function template
9419 // specialization, or, if not that,
9420 bool Cand1IsSpecialization = Cand1.Function &&
9421 Cand1.Function->getPrimaryTemplate();
9422 bool Cand2IsSpecialization = Cand2.Function &&
9423 Cand2.Function->getPrimaryTemplate();
9424 if (Cand1IsSpecialization != Cand2IsSpecialization)
9425 return Cand2IsSpecialization;
9427 // -- F1 and F2 are function template specializations, and the function
9428 // template for F1 is more specialized than the template for F2
9429 // according to the partial ordering rules described in 14.5.5.2, or,
9431 if (Cand1IsSpecialization && Cand2IsSpecialization) {
9432 if (FunctionTemplateDecl *BetterTemplate
9433 = S.getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(),
9434 Cand2.Function->getPrimaryTemplate(),
9436 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion
9438 Cand1.ExplicitCallArguments,
9439 Cand2.ExplicitCallArguments))
9440 return BetterTemplate == Cand1.Function->getPrimaryTemplate();
9443 // -- F1 is a constructor for a class D, F2 is a constructor for a base
9444 // class B of D, and for all arguments the corresponding parameters of
9445 // F1 and F2 have the same type.
9446 // FIXME: Implement the "all parameters have the same type" check.
9447 bool Cand1IsInherited =
9448 dyn_cast_or_null<ConstructorUsingShadowDecl>(Cand1.FoundDecl.getDecl());
9449 bool Cand2IsInherited =
9450 dyn_cast_or_null<ConstructorUsingShadowDecl>(Cand2.FoundDecl.getDecl());
9451 if (Cand1IsInherited != Cand2IsInherited)
9452 return Cand2IsInherited;
9453 else if (Cand1IsInherited) {
9454 assert(Cand2IsInherited);
9455 auto *Cand1Class = cast<CXXRecordDecl>(Cand1.Function->getDeclContext());
9456 auto *Cand2Class = cast<CXXRecordDecl>(Cand2.Function->getDeclContext());
9457 if (Cand1Class->isDerivedFrom(Cand2Class))
9459 if (Cand2Class->isDerivedFrom(Cand1Class))
9461 // Inherited from sibling base classes: still ambiguous.
9464 // -- F2 is a rewritten candidate (12.4.1.2) and F1 is not
9465 // -- F1 and F2 are rewritten candidates, and F2 is a synthesized candidate
9466 // with reversed order of parameters and F1 is not
9468 // We rank reversed + different operator as worse than just reversed, but
9469 // that comparison can never happen, because we only consider reversing for
9470 // the maximally-rewritten operator (== or <=>).
9471 if (Cand1.RewriteKind != Cand2.RewriteKind)
9472 return Cand1.RewriteKind < Cand2.RewriteKind;
9474 // Check C++17 tie-breakers for deduction guides.
9476 auto *Guide1 = dyn_cast_or_null<CXXDeductionGuideDecl>(Cand1.Function);
9477 auto *Guide2 = dyn_cast_or_null<CXXDeductionGuideDecl>(Cand2.Function);
9478 if (Guide1 && Guide2) {
9479 // -- F1 is generated from a deduction-guide and F2 is not
9480 if (Guide1->isImplicit() != Guide2->isImplicit())
9481 return Guide2->isImplicit();
9483 // -- F1 is the copy deduction candidate(16.3.1.8) and F2 is not
9484 if (Guide1->isCopyDeductionCandidate())
9489 // Check for enable_if value-based overload resolution.
9490 if (Cand1.Function && Cand2.Function) {
9491 Comparison Cmp = compareEnableIfAttrs(S, Cand1.Function, Cand2.Function);
9492 if (Cmp != Comparison::Equal)
9493 return Cmp == Comparison::Better;
9496 if (S.getLangOpts().CUDA && Cand1.Function && Cand2.Function) {
9497 FunctionDecl *Caller = dyn_cast<FunctionDecl>(S.CurContext);
9498 return S.IdentifyCUDAPreference(Caller, Cand1.Function) >
9499 S.IdentifyCUDAPreference(Caller, Cand2.Function);
9502 bool HasPS1 = Cand1.Function != nullptr &&
9503 functionHasPassObjectSizeParams(Cand1.Function);
9504 bool HasPS2 = Cand2.Function != nullptr &&
9505 functionHasPassObjectSizeParams(Cand2.Function);
9506 if (HasPS1 != HasPS2 && HasPS1)
9509 return isBetterMultiversionCandidate(Cand1, Cand2);
9512 /// Determine whether two declarations are "equivalent" for the purposes of
9513 /// name lookup and overload resolution. This applies when the same internal/no
9514 /// linkage entity is defined by two modules (probably by textually including
9515 /// the same header). In such a case, we don't consider the declarations to
9516 /// declare the same entity, but we also don't want lookups with both
9517 /// declarations visible to be ambiguous in some cases (this happens when using
9518 /// a modularized libstdc++).
9519 bool Sema::isEquivalentInternalLinkageDeclaration(const NamedDecl *A,
9520 const NamedDecl *B) {
9521 auto *VA = dyn_cast_or_null<ValueDecl>(A);
9522 auto *VB = dyn_cast_or_null<ValueDecl>(B);
9526 // The declarations must be declaring the same name as an internal linkage
9527 // entity in different modules.
9528 if (!VA->getDeclContext()->getRedeclContext()->Equals(
9529 VB->getDeclContext()->getRedeclContext()) ||
9530 getOwningModule(const_cast<ValueDecl *>(VA)) ==
9531 getOwningModule(const_cast<ValueDecl *>(VB)) ||
9532 VA->isExternallyVisible() || VB->isExternallyVisible())
9535 // Check that the declarations appear to be equivalent.
9537 // FIXME: Checking the type isn't really enough to resolve the ambiguity.
9538 // For constants and functions, we should check the initializer or body is
9539 // the same. For non-constant variables, we shouldn't allow it at all.
9540 if (Context.hasSameType(VA->getType(), VB->getType()))
9543 // Enum constants within unnamed enumerations will have different types, but
9544 // may still be similar enough to be interchangeable for our purposes.
9545 if (auto *EA = dyn_cast<EnumConstantDecl>(VA)) {
9546 if (auto *EB = dyn_cast<EnumConstantDecl>(VB)) {
9547 // Only handle anonymous enums. If the enumerations were named and
9548 // equivalent, they would have been merged to the same type.
9549 auto *EnumA = cast<EnumDecl>(EA->getDeclContext());
9550 auto *EnumB = cast<EnumDecl>(EB->getDeclContext());
9551 if (EnumA->hasNameForLinkage() || EnumB->hasNameForLinkage() ||
9552 !Context.hasSameType(EnumA->getIntegerType(),
9553 EnumB->getIntegerType()))
9555 // Allow this only if the value is the same for both enumerators.
9556 return llvm::APSInt::isSameValue(EA->getInitVal(), EB->getInitVal());
9560 // Nothing else is sufficiently similar.
9564 void Sema::diagnoseEquivalentInternalLinkageDeclarations(
9565 SourceLocation Loc, const NamedDecl *D, ArrayRef<const NamedDecl *> Equiv) {
9566 Diag(Loc, diag::ext_equivalent_internal_linkage_decl_in_modules) << D;
9568 Module *M = getOwningModule(const_cast<NamedDecl*>(D));
9569 Diag(D->getLocation(), diag::note_equivalent_internal_linkage_decl)
9570 << !M << (M ? M->getFullModuleName() : "");
9572 for (auto *E : Equiv) {
9573 Module *M = getOwningModule(const_cast<NamedDecl*>(E));
9574 Diag(E->getLocation(), diag::note_equivalent_internal_linkage_decl)
9575 << !M << (M ? M->getFullModuleName() : "");
9579 /// Computes the best viable function (C++ 13.3.3)
9580 /// within an overload candidate set.
9582 /// \param Loc The location of the function name (or operator symbol) for
9583 /// which overload resolution occurs.
9585 /// \param Best If overload resolution was successful or found a deleted
9586 /// function, \p Best points to the candidate function found.
9588 /// \returns The result of overload resolution.
9590 OverloadCandidateSet::BestViableFunction(Sema &S, SourceLocation Loc,
9592 llvm::SmallVector<OverloadCandidate *, 16> Candidates;
9593 std::transform(begin(), end(), std::back_inserter(Candidates),
9594 [](OverloadCandidate &Cand) { return &Cand; });
9596 // [CUDA] HD->H or HD->D calls are technically not allowed by CUDA but
9597 // are accepted by both clang and NVCC. However, during a particular
9598 // compilation mode only one call variant is viable. We need to
9599 // exclude non-viable overload candidates from consideration based
9600 // only on their host/device attributes. Specifically, if one
9601 // candidate call is WrongSide and the other is SameSide, we ignore
9602 // the WrongSide candidate.
9603 if (S.getLangOpts().CUDA) {
9604 const FunctionDecl *Caller = dyn_cast<FunctionDecl>(S.CurContext);
9605 bool ContainsSameSideCandidate =
9606 llvm::any_of(Candidates, [&](OverloadCandidate *Cand) {
9607 // Check viable function only.
9608 return Cand->Viable && Cand->Function &&
9609 S.IdentifyCUDAPreference(Caller, Cand->Function) ==
9612 if (ContainsSameSideCandidate) {
9613 auto IsWrongSideCandidate = [&](OverloadCandidate *Cand) {
9614 // Check viable function only to avoid unnecessary data copying/moving.
9615 return Cand->Viable && Cand->Function &&
9616 S.IdentifyCUDAPreference(Caller, Cand->Function) ==
9617 Sema::CFP_WrongSide;
9619 llvm::erase_if(Candidates, IsWrongSideCandidate);
9623 // Find the best viable function.
9625 for (auto *Cand : Candidates)
9627 if (Best == end() ||
9628 isBetterOverloadCandidate(S, *Cand, *Best, Loc, Kind))
9631 // If we didn't find any viable functions, abort.
9633 return OR_No_Viable_Function;
9635 llvm::SmallVector<const NamedDecl *, 4> EquivalentCands;
9637 // Make sure that this function is better than every other viable
9638 // function. If not, we have an ambiguity.
9639 for (auto *Cand : Candidates) {
9640 if (Cand->Viable && Cand != Best &&
9641 !isBetterOverloadCandidate(S, *Best, *Cand, Loc, Kind)) {
9642 if (S.isEquivalentInternalLinkageDeclaration(Best->Function,
9644 EquivalentCands.push_back(Cand->Function);
9649 return OR_Ambiguous;
9653 // Best is the best viable function.
9654 if (Best->Function && Best->Function->isDeleted())
9657 if (!EquivalentCands.empty())
9658 S.diagnoseEquivalentInternalLinkageDeclarations(Loc, Best->Function,
9666 enum OverloadCandidateKind {
9669 oc_reversed_binary_operator,
9671 oc_implicit_default_constructor,
9672 oc_implicit_copy_constructor,
9673 oc_implicit_move_constructor,
9674 oc_implicit_copy_assignment,
9675 oc_implicit_move_assignment,
9676 oc_inherited_constructor
9679 enum OverloadCandidateSelect {
9682 ocs_described_template,
9685 static std::pair<OverloadCandidateKind, OverloadCandidateSelect>
9686 ClassifyOverloadCandidate(Sema &S, NamedDecl *Found, FunctionDecl *Fn,
9687 OverloadCandidateRewriteKind CRK,
9688 std::string &Description) {
9690 bool isTemplate = Fn->isTemplateDecl() || Found->isTemplateDecl();
9691 if (FunctionTemplateDecl *FunTmpl = Fn->getPrimaryTemplate()) {
9693 Description = S.getTemplateArgumentBindingsText(
9694 FunTmpl->getTemplateParameters(), *Fn->getTemplateSpecializationArgs());
9697 OverloadCandidateSelect Select = [&]() {
9698 if (!Description.empty())
9699 return ocs_described_template;
9700 return isTemplate ? ocs_template : ocs_non_template;
9703 OverloadCandidateKind Kind = [&]() {
9704 if (CRK & CRK_Reversed)
9705 return oc_reversed_binary_operator;
9707 if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn)) {
9708 if (!Ctor->isImplicit()) {
9709 if (isa<ConstructorUsingShadowDecl>(Found))
9710 return oc_inherited_constructor;
9712 return oc_constructor;
9715 if (Ctor->isDefaultConstructor())
9716 return oc_implicit_default_constructor;
9718 if (Ctor->isMoveConstructor())
9719 return oc_implicit_move_constructor;
9721 assert(Ctor->isCopyConstructor() &&
9722 "unexpected sort of implicit constructor");
9723 return oc_implicit_copy_constructor;
9726 if (CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Fn)) {
9727 // This actually gets spelled 'candidate function' for now, but
9728 // it doesn't hurt to split it out.
9729 if (!Meth->isImplicit())
9732 if (Meth->isMoveAssignmentOperator())
9733 return oc_implicit_move_assignment;
9735 if (Meth->isCopyAssignmentOperator())
9736 return oc_implicit_copy_assignment;
9738 assert(isa<CXXConversionDecl>(Meth) && "expected conversion");
9745 return std::make_pair(Kind, Select);
9748 void MaybeEmitInheritedConstructorNote(Sema &S, Decl *FoundDecl) {
9749 // FIXME: It'd be nice to only emit a note once per using-decl per overload
9751 if (auto *Shadow = dyn_cast<ConstructorUsingShadowDecl>(FoundDecl))
9752 S.Diag(FoundDecl->getLocation(),
9753 diag::note_ovl_candidate_inherited_constructor)
9754 << Shadow->getNominatedBaseClass();
9757 } // end anonymous namespace
9759 static bool isFunctionAlwaysEnabled(const ASTContext &Ctx,
9760 const FunctionDecl *FD) {
9761 for (auto *EnableIf : FD->specific_attrs<EnableIfAttr>()) {
9763 if (EnableIf->getCond()->isValueDependent() ||
9764 !EnableIf->getCond()->EvaluateAsBooleanCondition(AlwaysTrue, Ctx))
9772 /// Returns true if we can take the address of the function.
9774 /// \param Complain - If true, we'll emit a diagnostic
9775 /// \param InOverloadResolution - For the purposes of emitting a diagnostic, are
9776 /// we in overload resolution?
9777 /// \param Loc - The location of the statement we're complaining about. Ignored
9778 /// if we're not complaining, or if we're in overload resolution.
9779 static bool checkAddressOfFunctionIsAvailable(Sema &S, const FunctionDecl *FD,
9781 bool InOverloadResolution,
9782 SourceLocation Loc) {
9783 if (!isFunctionAlwaysEnabled(S.Context, FD)) {
9785 if (InOverloadResolution)
9786 S.Diag(FD->getBeginLoc(),
9787 diag::note_addrof_ovl_candidate_disabled_by_enable_if_attr);
9789 S.Diag(Loc, diag::err_addrof_function_disabled_by_enable_if_attr) << FD;
9794 auto I = llvm::find_if(FD->parameters(), [](const ParmVarDecl *P) {
9795 return P->hasAttr<PassObjectSizeAttr>();
9797 if (I == FD->param_end())
9801 // Add one to ParamNo because it's user-facing
9802 unsigned ParamNo = std::distance(FD->param_begin(), I) + 1;
9803 if (InOverloadResolution)
9804 S.Diag(FD->getLocation(),
9805 diag::note_ovl_candidate_has_pass_object_size_params)
9808 S.Diag(Loc, diag::err_address_of_function_with_pass_object_size_params)
9814 static bool checkAddressOfCandidateIsAvailable(Sema &S,
9815 const FunctionDecl *FD) {
9816 return checkAddressOfFunctionIsAvailable(S, FD, /*Complain=*/true,
9817 /*InOverloadResolution=*/true,
9818 /*Loc=*/SourceLocation());
9821 bool Sema::checkAddressOfFunctionIsAvailable(const FunctionDecl *Function,
9823 SourceLocation Loc) {
9824 return ::checkAddressOfFunctionIsAvailable(*this, Function, Complain,
9825 /*InOverloadResolution=*/false,
9829 // Notes the location of an overload candidate.
9830 void Sema::NoteOverloadCandidate(NamedDecl *Found, FunctionDecl *Fn,
9831 OverloadCandidateRewriteKind RewriteKind,
9832 QualType DestType, bool TakingAddress) {
9833 if (TakingAddress && !checkAddressOfCandidateIsAvailable(*this, Fn))
9835 if (Fn->isMultiVersion() && Fn->hasAttr<TargetAttr>() &&
9836 !Fn->getAttr<TargetAttr>()->isDefaultVersion())
9840 std::pair<OverloadCandidateKind, OverloadCandidateSelect> KSPair =
9841 ClassifyOverloadCandidate(*this, Found, Fn, RewriteKind, FnDesc);
9842 PartialDiagnostic PD = PDiag(diag::note_ovl_candidate)
9843 << (unsigned)KSPair.first << (unsigned)KSPair.second
9846 HandleFunctionTypeMismatch(PD, Fn->getType(), DestType);
9847 Diag(Fn->getLocation(), PD);
9848 MaybeEmitInheritedConstructorNote(*this, Found);
9851 // Notes the location of all overload candidates designated through
9853 void Sema::NoteAllOverloadCandidates(Expr *OverloadedExpr, QualType DestType,
9854 bool TakingAddress) {
9855 assert(OverloadedExpr->getType() == Context.OverloadTy);
9857 OverloadExpr::FindResult Ovl = OverloadExpr::find(OverloadedExpr);
9858 OverloadExpr *OvlExpr = Ovl.Expression;
9860 for (UnresolvedSetIterator I = OvlExpr->decls_begin(),
9861 IEnd = OvlExpr->decls_end();
9863 if (FunctionTemplateDecl *FunTmpl =
9864 dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()) ) {
9865 NoteOverloadCandidate(*I, FunTmpl->getTemplatedDecl(), CRK_None, DestType,
9867 } else if (FunctionDecl *Fun
9868 = dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()) ) {
9869 NoteOverloadCandidate(*I, Fun, CRK_None, DestType, TakingAddress);
9874 /// Diagnoses an ambiguous conversion. The partial diagnostic is the
9875 /// "lead" diagnostic; it will be given two arguments, the source and
9876 /// target types of the conversion.
9877 void ImplicitConversionSequence::DiagnoseAmbiguousConversion(
9879 SourceLocation CaretLoc,
9880 const PartialDiagnostic &PDiag) const {
9881 S.Diag(CaretLoc, PDiag)
9882 << Ambiguous.getFromType() << Ambiguous.getToType();
9883 // FIXME: The note limiting machinery is borrowed from
9884 // OverloadCandidateSet::NoteCandidates; there's an opportunity for
9885 // refactoring here.
9886 const OverloadsShown ShowOverloads = S.Diags.getShowOverloads();
9887 unsigned CandsShown = 0;
9888 AmbiguousConversionSequence::const_iterator I, E;
9889 for (I = Ambiguous.begin(), E = Ambiguous.end(); I != E; ++I) {
9890 if (CandsShown >= 4 && ShowOverloads == Ovl_Best)
9893 S.NoteOverloadCandidate(I->first, I->second);
9896 S.Diag(SourceLocation(), diag::note_ovl_too_many_candidates) << int(E - I);
9899 static void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand,
9900 unsigned I, bool TakingCandidateAddress) {
9901 const ImplicitConversionSequence &Conv = Cand->Conversions[I];
9902 assert(Conv.isBad());
9903 assert(Cand->Function && "for now, candidate must be a function");
9904 FunctionDecl *Fn = Cand->Function;
9906 // There's a conversion slot for the object argument if this is a
9907 // non-constructor method. Note that 'I' corresponds the
9908 // conversion-slot index.
9909 bool isObjectArgument = false;
9910 if (isa<CXXMethodDecl>(Fn) && !isa<CXXConstructorDecl>(Fn)) {
9912 isObjectArgument = true;
9918 std::pair<OverloadCandidateKind, OverloadCandidateSelect> FnKindPair =
9919 ClassifyOverloadCandidate(S, Cand->FoundDecl, Fn, Cand->RewriteKind,
9922 Expr *FromExpr = Conv.Bad.FromExpr;
9923 QualType FromTy = Conv.Bad.getFromType();
9924 QualType ToTy = Conv.Bad.getToType();
9926 if (FromTy == S.Context.OverloadTy) {
9927 assert(FromExpr && "overload set argument came from implicit argument?");
9928 Expr *E = FromExpr->IgnoreParens();
9929 if (isa<UnaryOperator>(E))
9930 E = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens();
9931 DeclarationName Name = cast<OverloadExpr>(E)->getName();
9933 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_overload)
9934 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
9935 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << ToTy
9937 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
9941 // Do some hand-waving analysis to see if the non-viability is due
9942 // to a qualifier mismatch.
9943 CanQualType CFromTy = S.Context.getCanonicalType(FromTy);
9944 CanQualType CToTy = S.Context.getCanonicalType(ToTy);
9945 if (CanQual<ReferenceType> RT = CToTy->getAs<ReferenceType>())
9946 CToTy = RT->getPointeeType();
9948 // TODO: detect and diagnose the full richness of const mismatches.
9949 if (CanQual<PointerType> FromPT = CFromTy->getAs<PointerType>())
9950 if (CanQual<PointerType> ToPT = CToTy->getAs<PointerType>()) {
9951 CFromTy = FromPT->getPointeeType();
9952 CToTy = ToPT->getPointeeType();
9956 if (CToTy.getUnqualifiedType() == CFromTy.getUnqualifiedType() &&
9957 !CToTy.isAtLeastAsQualifiedAs(CFromTy)) {
9958 Qualifiers FromQs = CFromTy.getQualifiers();
9959 Qualifiers ToQs = CToTy.getQualifiers();
9961 if (FromQs.getAddressSpace() != ToQs.getAddressSpace()) {
9962 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_addrspace)
9963 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
9964 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
9965 << ToTy << (unsigned)isObjectArgument << I + 1;
9966 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
9970 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) {
9971 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_ownership)
9972 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
9973 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
9974 << FromQs.getObjCLifetime() << ToQs.getObjCLifetime()
9975 << (unsigned)isObjectArgument << I + 1;
9976 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
9980 if (FromQs.getObjCGCAttr() != ToQs.getObjCGCAttr()) {
9981 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_gc)
9982 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
9983 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
9984 << FromQs.getObjCGCAttr() << ToQs.getObjCGCAttr()
9985 << (unsigned)isObjectArgument << I + 1;
9986 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
9990 if (FromQs.hasUnaligned() != ToQs.hasUnaligned()) {
9991 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_unaligned)
9992 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
9993 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
9994 << FromQs.hasUnaligned() << I + 1;
9995 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
9999 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers();
10000 assert(CVR && "unexpected qualifiers mismatch");
10002 if (isObjectArgument) {
10003 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr_this)
10004 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
10005 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
10008 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr)
10009 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
10010 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
10011 << (CVR - 1) << I + 1;
10013 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10017 // Special diagnostic for failure to convert an initializer list, since
10018 // telling the user that it has type void is not useful.
10019 if (FromExpr && isa<InitListExpr>(FromExpr)) {
10020 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_list_argument)
10021 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
10022 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
10023 << ToTy << (unsigned)isObjectArgument << I + 1;
10024 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10028 // Diagnose references or pointers to incomplete types differently,
10029 // since it's far from impossible that the incompleteness triggered
10031 QualType TempFromTy = FromTy.getNonReferenceType();
10032 if (const PointerType *PTy = TempFromTy->getAs<PointerType>())
10033 TempFromTy = PTy->getPointeeType();
10034 if (TempFromTy->isIncompleteType()) {
10035 // Emit the generic diagnostic and, optionally, add the hints to it.
10036 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv_incomplete)
10037 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
10038 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
10039 << ToTy << (unsigned)isObjectArgument << I + 1
10040 << (unsigned)(Cand->Fix.Kind);
10042 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10046 // Diagnose base -> derived pointer conversions.
10047 unsigned BaseToDerivedConversion = 0;
10048 if (const PointerType *FromPtrTy = FromTy->getAs<PointerType>()) {
10049 if (const PointerType *ToPtrTy = ToTy->getAs<PointerType>()) {
10050 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs(
10051 FromPtrTy->getPointeeType()) &&
10052 !FromPtrTy->getPointeeType()->isIncompleteType() &&
10053 !ToPtrTy->getPointeeType()->isIncompleteType() &&
10054 S.IsDerivedFrom(SourceLocation(), ToPtrTy->getPointeeType(),
10055 FromPtrTy->getPointeeType()))
10056 BaseToDerivedConversion = 1;
10058 } else if (const ObjCObjectPointerType *FromPtrTy
10059 = FromTy->getAs<ObjCObjectPointerType>()) {
10060 if (const ObjCObjectPointerType *ToPtrTy
10061 = ToTy->getAs<ObjCObjectPointerType>())
10062 if (const ObjCInterfaceDecl *FromIface = FromPtrTy->getInterfaceDecl())
10063 if (const ObjCInterfaceDecl *ToIface = ToPtrTy->getInterfaceDecl())
10064 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs(
10065 FromPtrTy->getPointeeType()) &&
10066 FromIface->isSuperClassOf(ToIface))
10067 BaseToDerivedConversion = 2;
10068 } else if (const ReferenceType *ToRefTy = ToTy->getAs<ReferenceType>()) {
10069 if (ToRefTy->getPointeeType().isAtLeastAsQualifiedAs(FromTy) &&
10070 !FromTy->isIncompleteType() &&
10071 !ToRefTy->getPointeeType()->isIncompleteType() &&
10072 S.IsDerivedFrom(SourceLocation(), ToRefTy->getPointeeType(), FromTy)) {
10073 BaseToDerivedConversion = 3;
10074 } else if (ToTy->isLValueReferenceType() && !FromExpr->isLValue() &&
10075 ToTy.getNonReferenceType().getCanonicalType() ==
10076 FromTy.getNonReferenceType().getCanonicalType()) {
10077 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_lvalue)
10078 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
10079 << (unsigned)isObjectArgument << I + 1
10080 << (FromExpr ? FromExpr->getSourceRange() : SourceRange());
10081 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10086 if (BaseToDerivedConversion) {
10087 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_base_to_derived_conv)
10088 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
10089 << (FromExpr ? FromExpr->getSourceRange() : SourceRange())
10090 << (BaseToDerivedConversion - 1) << FromTy << ToTy << I + 1;
10091 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10095 if (isa<ObjCObjectPointerType>(CFromTy) &&
10096 isa<PointerType>(CToTy)) {
10097 Qualifiers FromQs = CFromTy.getQualifiers();
10098 Qualifiers ToQs = CToTy.getQualifiers();
10099 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) {
10100 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_arc_conv)
10101 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second
10102 << FnDesc << (FromExpr ? FromExpr->getSourceRange() : SourceRange())
10103 << FromTy << ToTy << (unsigned)isObjectArgument << I + 1;
10104 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10109 if (TakingCandidateAddress &&
10110 !checkAddressOfCandidateIsAvailable(S, Cand->Function))
10113 // Emit the generic diagnostic and, optionally, add the hints to it.
10114 PartialDiagnostic FDiag = S.PDiag(diag::note_ovl_candidate_bad_conv);
10115 FDiag << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
10116 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) << FromTy
10117 << ToTy << (unsigned)isObjectArgument << I + 1
10118 << (unsigned)(Cand->Fix.Kind);
10120 // If we can fix the conversion, suggest the FixIts.
10121 for (std::vector<FixItHint>::iterator HI = Cand->Fix.Hints.begin(),
10122 HE = Cand->Fix.Hints.end(); HI != HE; ++HI)
10124 S.Diag(Fn->getLocation(), FDiag);
10126 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10129 /// Additional arity mismatch diagnosis specific to a function overload
10130 /// candidates. This is not covered by the more general DiagnoseArityMismatch()
10131 /// over a candidate in any candidate set.
10132 static bool CheckArityMismatch(Sema &S, OverloadCandidate *Cand,
10133 unsigned NumArgs) {
10134 FunctionDecl *Fn = Cand->Function;
10135 unsigned MinParams = Fn->getMinRequiredArguments();
10137 // With invalid overloaded operators, it's possible that we think we
10138 // have an arity mismatch when in fact it looks like we have the
10139 // right number of arguments, because only overloaded operators have
10140 // the weird behavior of overloading member and non-member functions.
10141 // Just don't report anything.
10142 if (Fn->isInvalidDecl() &&
10143 Fn->getDeclName().getNameKind() == DeclarationName::CXXOperatorName)
10146 if (NumArgs < MinParams) {
10147 assert((Cand->FailureKind == ovl_fail_too_few_arguments) ||
10148 (Cand->FailureKind == ovl_fail_bad_deduction &&
10149 Cand->DeductionFailure.Result == Sema::TDK_TooFewArguments));
10151 assert((Cand->FailureKind == ovl_fail_too_many_arguments) ||
10152 (Cand->FailureKind == ovl_fail_bad_deduction &&
10153 Cand->DeductionFailure.Result == Sema::TDK_TooManyArguments));
10159 /// General arity mismatch diagnosis over a candidate in a candidate set.
10160 static void DiagnoseArityMismatch(Sema &S, NamedDecl *Found, Decl *D,
10161 unsigned NumFormalArgs) {
10162 assert(isa<FunctionDecl>(D) &&
10163 "The templated declaration should at least be a function"
10164 " when diagnosing bad template argument deduction due to too many"
10165 " or too few arguments");
10167 FunctionDecl *Fn = cast<FunctionDecl>(D);
10169 // TODO: treat calls to a missing default constructor as a special case
10170 const FunctionProtoType *FnTy = Fn->getType()->getAs<FunctionProtoType>();
10171 unsigned MinParams = Fn->getMinRequiredArguments();
10173 // at least / at most / exactly
10174 unsigned mode, modeCount;
10175 if (NumFormalArgs < MinParams) {
10176 if (MinParams != FnTy->getNumParams() || FnTy->isVariadic() ||
10177 FnTy->isTemplateVariadic())
10178 mode = 0; // "at least"
10180 mode = 2; // "exactly"
10181 modeCount = MinParams;
10183 if (MinParams != FnTy->getNumParams())
10184 mode = 1; // "at most"
10186 mode = 2; // "exactly"
10187 modeCount = FnTy->getNumParams();
10190 std::string Description;
10191 std::pair<OverloadCandidateKind, OverloadCandidateSelect> FnKindPair =
10192 ClassifyOverloadCandidate(S, Found, Fn, CRK_None, Description);
10194 if (modeCount == 1 && Fn->getParamDecl(0)->getDeclName())
10195 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity_one)
10196 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second
10197 << Description << mode << Fn->getParamDecl(0) << NumFormalArgs;
10199 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity)
10200 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second
10201 << Description << mode << modeCount << NumFormalArgs;
10203 MaybeEmitInheritedConstructorNote(S, Found);
10206 /// Arity mismatch diagnosis specific to a function overload candidate.
10207 static void DiagnoseArityMismatch(Sema &S, OverloadCandidate *Cand,
10208 unsigned NumFormalArgs) {
10209 if (!CheckArityMismatch(S, Cand, NumFormalArgs))
10210 DiagnoseArityMismatch(S, Cand->FoundDecl, Cand->Function, NumFormalArgs);
10213 static TemplateDecl *getDescribedTemplate(Decl *Templated) {
10214 if (TemplateDecl *TD = Templated->getDescribedTemplate())
10216 llvm_unreachable("Unsupported: Getting the described template declaration"
10217 " for bad deduction diagnosis");
10220 /// Diagnose a failed template-argument deduction.
10221 static void DiagnoseBadDeduction(Sema &S, NamedDecl *Found, Decl *Templated,
10222 DeductionFailureInfo &DeductionFailure,
10224 bool TakingCandidateAddress) {
10225 TemplateParameter Param = DeductionFailure.getTemplateParameter();
10227 (ParamD = Param.dyn_cast<TemplateTypeParmDecl*>()) ||
10228 (ParamD = Param.dyn_cast<NonTypeTemplateParmDecl*>()) ||
10229 (ParamD = Param.dyn_cast<TemplateTemplateParmDecl*>());
10230 switch (DeductionFailure.Result) {
10231 case Sema::TDK_Success:
10232 llvm_unreachable("TDK_success while diagnosing bad deduction");
10234 case Sema::TDK_Incomplete: {
10235 assert(ParamD && "no parameter found for incomplete deduction result");
10236 S.Diag(Templated->getLocation(),
10237 diag::note_ovl_candidate_incomplete_deduction)
10238 << ParamD->getDeclName();
10239 MaybeEmitInheritedConstructorNote(S, Found);
10243 case Sema::TDK_IncompletePack: {
10244 assert(ParamD && "no parameter found for incomplete deduction result");
10245 S.Diag(Templated->getLocation(),
10246 diag::note_ovl_candidate_incomplete_deduction_pack)
10247 << ParamD->getDeclName()
10248 << (DeductionFailure.getFirstArg()->pack_size() + 1)
10249 << *DeductionFailure.getFirstArg();
10250 MaybeEmitInheritedConstructorNote(S, Found);
10254 case Sema::TDK_Underqualified: {
10255 assert(ParamD && "no parameter found for bad qualifiers deduction result");
10256 TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD);
10258 QualType Param = DeductionFailure.getFirstArg()->getAsType();
10260 // Param will have been canonicalized, but it should just be a
10261 // qualified version of ParamD, so move the qualifiers to that.
10262 QualifierCollector Qs;
10264 QualType NonCanonParam = Qs.apply(S.Context, TParam->getTypeForDecl());
10265 assert(S.Context.hasSameType(Param, NonCanonParam));
10267 // Arg has also been canonicalized, but there's nothing we can do
10268 // about that. It also doesn't matter as much, because it won't
10269 // have any template parameters in it (because deduction isn't
10270 // done on dependent types).
10271 QualType Arg = DeductionFailure.getSecondArg()->getAsType();
10273 S.Diag(Templated->getLocation(), diag::note_ovl_candidate_underqualified)
10274 << ParamD->getDeclName() << Arg << NonCanonParam;
10275 MaybeEmitInheritedConstructorNote(S, Found);
10279 case Sema::TDK_Inconsistent: {
10280 assert(ParamD && "no parameter found for inconsistent deduction result");
10282 if (isa<TemplateTypeParmDecl>(ParamD))
10284 else if (isa<NonTypeTemplateParmDecl>(ParamD)) {
10285 // Deduction might have failed because we deduced arguments of two
10286 // different types for a non-type template parameter.
10287 // FIXME: Use a different TDK value for this.
10289 DeductionFailure.getFirstArg()->getNonTypeTemplateArgumentType();
10291 DeductionFailure.getSecondArg()->getNonTypeTemplateArgumentType();
10292 if (!T1.isNull() && !T2.isNull() && !S.Context.hasSameType(T1, T2)) {
10293 S.Diag(Templated->getLocation(),
10294 diag::note_ovl_candidate_inconsistent_deduction_types)
10295 << ParamD->getDeclName() << *DeductionFailure.getFirstArg() << T1
10296 << *DeductionFailure.getSecondArg() << T2;
10297 MaybeEmitInheritedConstructorNote(S, Found);
10306 S.Diag(Templated->getLocation(),
10307 diag::note_ovl_candidate_inconsistent_deduction)
10308 << which << ParamD->getDeclName() << *DeductionFailure.getFirstArg()
10309 << *DeductionFailure.getSecondArg();
10310 MaybeEmitInheritedConstructorNote(S, Found);
10314 case Sema::TDK_InvalidExplicitArguments:
10315 assert(ParamD && "no parameter found for invalid explicit arguments");
10316 if (ParamD->getDeclName())
10317 S.Diag(Templated->getLocation(),
10318 diag::note_ovl_candidate_explicit_arg_mismatch_named)
10319 << ParamD->getDeclName();
10322 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ParamD))
10323 index = TTP->getIndex();
10324 else if (NonTypeTemplateParmDecl *NTTP
10325 = dyn_cast<NonTypeTemplateParmDecl>(ParamD))
10326 index = NTTP->getIndex();
10328 index = cast<TemplateTemplateParmDecl>(ParamD)->getIndex();
10329 S.Diag(Templated->getLocation(),
10330 diag::note_ovl_candidate_explicit_arg_mismatch_unnamed)
10333 MaybeEmitInheritedConstructorNote(S, Found);
10336 case Sema::TDK_TooManyArguments:
10337 case Sema::TDK_TooFewArguments:
10338 DiagnoseArityMismatch(S, Found, Templated, NumArgs);
10341 case Sema::TDK_InstantiationDepth:
10342 S.Diag(Templated->getLocation(),
10343 diag::note_ovl_candidate_instantiation_depth);
10344 MaybeEmitInheritedConstructorNote(S, Found);
10347 case Sema::TDK_SubstitutionFailure: {
10348 // Format the template argument list into the argument string.
10349 SmallString<128> TemplateArgString;
10350 if (TemplateArgumentList *Args =
10351 DeductionFailure.getTemplateArgumentList()) {
10352 TemplateArgString = " ";
10353 TemplateArgString += S.getTemplateArgumentBindingsText(
10354 getDescribedTemplate(Templated)->getTemplateParameters(), *Args);
10357 // If this candidate was disabled by enable_if, say so.
10358 PartialDiagnosticAt *PDiag = DeductionFailure.getSFINAEDiagnostic();
10359 if (PDiag && PDiag->second.getDiagID() ==
10360 diag::err_typename_nested_not_found_enable_if) {
10361 // FIXME: Use the source range of the condition, and the fully-qualified
10362 // name of the enable_if template. These are both present in PDiag.
10363 S.Diag(PDiag->first, diag::note_ovl_candidate_disabled_by_enable_if)
10364 << "'enable_if'" << TemplateArgString;
10368 // We found a specific requirement that disabled the enable_if.
10369 if (PDiag && PDiag->second.getDiagID() ==
10370 diag::err_typename_nested_not_found_requirement) {
10371 S.Diag(Templated->getLocation(),
10372 diag::note_ovl_candidate_disabled_by_requirement)
10373 << PDiag->second.getStringArg(0) << TemplateArgString;
10377 // Format the SFINAE diagnostic into the argument string.
10378 // FIXME: Add a general mechanism to include a PartialDiagnostic *'s
10379 // formatted message in another diagnostic.
10380 SmallString<128> SFINAEArgString;
10383 SFINAEArgString = ": ";
10384 R = SourceRange(PDiag->first, PDiag->first);
10385 PDiag->second.EmitToString(S.getDiagnostics(), SFINAEArgString);
10388 S.Diag(Templated->getLocation(),
10389 diag::note_ovl_candidate_substitution_failure)
10390 << TemplateArgString << SFINAEArgString << R;
10391 MaybeEmitInheritedConstructorNote(S, Found);
10395 case Sema::TDK_DeducedMismatch:
10396 case Sema::TDK_DeducedMismatchNested: {
10397 // Format the template argument list into the argument string.
10398 SmallString<128> TemplateArgString;
10399 if (TemplateArgumentList *Args =
10400 DeductionFailure.getTemplateArgumentList()) {
10401 TemplateArgString = " ";
10402 TemplateArgString += S.getTemplateArgumentBindingsText(
10403 getDescribedTemplate(Templated)->getTemplateParameters(), *Args);
10406 S.Diag(Templated->getLocation(), diag::note_ovl_candidate_deduced_mismatch)
10407 << (*DeductionFailure.getCallArgIndex() + 1)
10408 << *DeductionFailure.getFirstArg() << *DeductionFailure.getSecondArg()
10409 << TemplateArgString
10410 << (DeductionFailure.Result == Sema::TDK_DeducedMismatchNested);
10414 case Sema::TDK_NonDeducedMismatch: {
10415 // FIXME: Provide a source location to indicate what we couldn't match.
10416 TemplateArgument FirstTA = *DeductionFailure.getFirstArg();
10417 TemplateArgument SecondTA = *DeductionFailure.getSecondArg();
10418 if (FirstTA.getKind() == TemplateArgument::Template &&
10419 SecondTA.getKind() == TemplateArgument::Template) {
10420 TemplateName FirstTN = FirstTA.getAsTemplate();
10421 TemplateName SecondTN = SecondTA.getAsTemplate();
10422 if (FirstTN.getKind() == TemplateName::Template &&
10423 SecondTN.getKind() == TemplateName::Template) {
10424 if (FirstTN.getAsTemplateDecl()->getName() ==
10425 SecondTN.getAsTemplateDecl()->getName()) {
10426 // FIXME: This fixes a bad diagnostic where both templates are named
10427 // the same. This particular case is a bit difficult since:
10428 // 1) It is passed as a string to the diagnostic printer.
10429 // 2) The diagnostic printer only attempts to find a better
10430 // name for types, not decls.
10431 // Ideally, this should folded into the diagnostic printer.
10432 S.Diag(Templated->getLocation(),
10433 diag::note_ovl_candidate_non_deduced_mismatch_qualified)
10434 << FirstTN.getAsTemplateDecl() << SecondTN.getAsTemplateDecl();
10440 if (TakingCandidateAddress && isa<FunctionDecl>(Templated) &&
10441 !checkAddressOfCandidateIsAvailable(S, cast<FunctionDecl>(Templated)))
10444 // FIXME: For generic lambda parameters, check if the function is a lambda
10445 // call operator, and if so, emit a prettier and more informative
10446 // diagnostic that mentions 'auto' and lambda in addition to
10447 // (or instead of?) the canonical template type parameters.
10448 S.Diag(Templated->getLocation(),
10449 diag::note_ovl_candidate_non_deduced_mismatch)
10450 << FirstTA << SecondTA;
10453 // TODO: diagnose these individually, then kill off
10454 // note_ovl_candidate_bad_deduction, which is uselessly vague.
10455 case Sema::TDK_MiscellaneousDeductionFailure:
10456 S.Diag(Templated->getLocation(), diag::note_ovl_candidate_bad_deduction);
10457 MaybeEmitInheritedConstructorNote(S, Found);
10459 case Sema::TDK_CUDATargetMismatch:
10460 S.Diag(Templated->getLocation(),
10461 diag::note_cuda_ovl_candidate_target_mismatch);
10466 /// Diagnose a failed template-argument deduction, for function calls.
10467 static void DiagnoseBadDeduction(Sema &S, OverloadCandidate *Cand,
10469 bool TakingCandidateAddress) {
10470 unsigned TDK = Cand->DeductionFailure.Result;
10471 if (TDK == Sema::TDK_TooFewArguments || TDK == Sema::TDK_TooManyArguments) {
10472 if (CheckArityMismatch(S, Cand, NumArgs))
10475 DiagnoseBadDeduction(S, Cand->FoundDecl, Cand->Function, // pattern
10476 Cand->DeductionFailure, NumArgs, TakingCandidateAddress);
10479 /// CUDA: diagnose an invalid call across targets.
10480 static void DiagnoseBadTarget(Sema &S, OverloadCandidate *Cand) {
10481 FunctionDecl *Caller = cast<FunctionDecl>(S.CurContext);
10482 FunctionDecl *Callee = Cand->Function;
10484 Sema::CUDAFunctionTarget CallerTarget = S.IdentifyCUDATarget(Caller),
10485 CalleeTarget = S.IdentifyCUDATarget(Callee);
10487 std::string FnDesc;
10488 std::pair<OverloadCandidateKind, OverloadCandidateSelect> FnKindPair =
10489 ClassifyOverloadCandidate(S, Cand->FoundDecl, Callee, Cand->RewriteKind,
10492 S.Diag(Callee->getLocation(), diag::note_ovl_candidate_bad_target)
10493 << (unsigned)FnKindPair.first << (unsigned)ocs_non_template
10494 << FnDesc /* Ignored */
10495 << CalleeTarget << CallerTarget;
10497 // This could be an implicit constructor for which we could not infer the
10498 // target due to a collsion. Diagnose that case.
10499 CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Callee);
10500 if (Meth != nullptr && Meth->isImplicit()) {
10501 CXXRecordDecl *ParentClass = Meth->getParent();
10502 Sema::CXXSpecialMember CSM;
10504 switch (FnKindPair.first) {
10507 case oc_implicit_default_constructor:
10508 CSM = Sema::CXXDefaultConstructor;
10510 case oc_implicit_copy_constructor:
10511 CSM = Sema::CXXCopyConstructor;
10513 case oc_implicit_move_constructor:
10514 CSM = Sema::CXXMoveConstructor;
10516 case oc_implicit_copy_assignment:
10517 CSM = Sema::CXXCopyAssignment;
10519 case oc_implicit_move_assignment:
10520 CSM = Sema::CXXMoveAssignment;
10524 bool ConstRHS = false;
10525 if (Meth->getNumParams()) {
10526 if (const ReferenceType *RT =
10527 Meth->getParamDecl(0)->getType()->getAs<ReferenceType>()) {
10528 ConstRHS = RT->getPointeeType().isConstQualified();
10532 S.inferCUDATargetForImplicitSpecialMember(ParentClass, CSM, Meth,
10533 /* ConstRHS */ ConstRHS,
10534 /* Diagnose */ true);
10538 static void DiagnoseFailedEnableIfAttr(Sema &S, OverloadCandidate *Cand) {
10539 FunctionDecl *Callee = Cand->Function;
10540 EnableIfAttr *Attr = static_cast<EnableIfAttr*>(Cand->DeductionFailure.Data);
10542 S.Diag(Callee->getLocation(),
10543 diag::note_ovl_candidate_disabled_by_function_cond_attr)
10544 << Attr->getCond()->getSourceRange() << Attr->getMessage();
10547 static void DiagnoseFailedExplicitSpec(Sema &S, OverloadCandidate *Cand) {
10548 ExplicitSpecifier ES;
10549 const char *DeclName;
10550 switch (Cand->Function->getDeclKind()) {
10551 case Decl::Kind::CXXConstructor:
10552 ES = cast<CXXConstructorDecl>(Cand->Function)->getExplicitSpecifier();
10553 DeclName = "constructor";
10555 case Decl::Kind::CXXConversion:
10556 ES = cast<CXXConversionDecl>(Cand->Function)->getExplicitSpecifier();
10557 DeclName = "conversion operator";
10559 case Decl::Kind::CXXDeductionGuide:
10560 ES = cast<CXXDeductionGuideDecl>(Cand->Function)->getExplicitSpecifier();
10561 DeclName = "deductiong guide";
10564 llvm_unreachable("invalid Decl");
10566 assert(ES.getExpr() && "null expression should be handled before");
10567 S.Diag(Cand->Function->getLocation(),
10568 diag::note_ovl_candidate_explicit_forbidden)
10570 S.Diag(ES.getExpr()->getBeginLoc(),
10571 diag::note_explicit_bool_resolved_to_true);
10574 static void DiagnoseOpenCLExtensionDisabled(Sema &S, OverloadCandidate *Cand) {
10575 FunctionDecl *Callee = Cand->Function;
10577 S.Diag(Callee->getLocation(),
10578 diag::note_ovl_candidate_disabled_by_extension)
10579 << S.getOpenCLExtensionsFromDeclExtMap(Callee);
10582 /// Generates a 'note' diagnostic for an overload candidate. We've
10583 /// already generated a primary error at the call site.
10585 /// It really does need to be a single diagnostic with its caret
10586 /// pointed at the candidate declaration. Yes, this creates some
10587 /// major challenges of technical writing. Yes, this makes pointing
10588 /// out problems with specific arguments quite awkward. It's still
10589 /// better than generating twenty screens of text for every failed
10592 /// It would be great to be able to express per-candidate problems
10593 /// more richly for those diagnostic clients that cared, but we'd
10594 /// still have to be just as careful with the default diagnostics.
10595 /// \param CtorDestAS Addr space of object being constructed (for ctor
10596 /// candidates only).
10597 static void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand,
10599 bool TakingCandidateAddress,
10600 LangAS CtorDestAS = LangAS::Default) {
10601 FunctionDecl *Fn = Cand->Function;
10603 // Note deleted candidates, but only if they're viable.
10604 if (Cand->Viable) {
10605 if (Fn->isDeleted()) {
10606 std::string FnDesc;
10607 std::pair<OverloadCandidateKind, OverloadCandidateSelect> FnKindPair =
10608 ClassifyOverloadCandidate(S, Cand->FoundDecl, Fn, Cand->RewriteKind,
10611 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_deleted)
10612 << (unsigned)FnKindPair.first << (unsigned)FnKindPair.second << FnDesc
10613 << (Fn->isDeleted() ? (Fn->isDeletedAsWritten() ? 1 : 2) : 0);
10614 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10618 // We don't really have anything else to say about viable candidates.
10619 S.NoteOverloadCandidate(Cand->FoundDecl, Fn, Cand->RewriteKind);
10623 switch (Cand->FailureKind) {
10624 case ovl_fail_too_many_arguments:
10625 case ovl_fail_too_few_arguments:
10626 return DiagnoseArityMismatch(S, Cand, NumArgs);
10628 case ovl_fail_bad_deduction:
10629 return DiagnoseBadDeduction(S, Cand, NumArgs,
10630 TakingCandidateAddress);
10632 case ovl_fail_illegal_constructor: {
10633 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_illegal_constructor)
10634 << (Fn->getPrimaryTemplate() ? 1 : 0);
10635 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10639 case ovl_fail_object_addrspace_mismatch: {
10640 Qualifiers QualsForPrinting;
10641 QualsForPrinting.setAddressSpace(CtorDestAS);
10642 S.Diag(Fn->getLocation(),
10643 diag::note_ovl_candidate_illegal_constructor_adrspace_mismatch)
10644 << QualsForPrinting;
10645 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10649 case ovl_fail_trivial_conversion:
10650 case ovl_fail_bad_final_conversion:
10651 case ovl_fail_final_conversion_not_exact:
10652 return S.NoteOverloadCandidate(Cand->FoundDecl, Fn, Cand->RewriteKind);
10654 case ovl_fail_bad_conversion: {
10655 unsigned I = (Cand->IgnoreObjectArgument ? 1 : 0);
10656 for (unsigned N = Cand->Conversions.size(); I != N; ++I)
10657 if (Cand->Conversions[I].isBad())
10658 return DiagnoseBadConversion(S, Cand, I, TakingCandidateAddress);
10660 // FIXME: this currently happens when we're called from SemaInit
10661 // when user-conversion overload fails. Figure out how to handle
10662 // those conditions and diagnose them well.
10663 return S.NoteOverloadCandidate(Cand->FoundDecl, Fn, Cand->RewriteKind);
10666 case ovl_fail_bad_target:
10667 return DiagnoseBadTarget(S, Cand);
10669 case ovl_fail_enable_if:
10670 return DiagnoseFailedEnableIfAttr(S, Cand);
10672 case ovl_fail_explicit_resolved:
10673 return DiagnoseFailedExplicitSpec(S, Cand);
10675 case ovl_fail_ext_disabled:
10676 return DiagnoseOpenCLExtensionDisabled(S, Cand);
10678 case ovl_fail_inhctor_slice:
10679 // It's generally not interesting to note copy/move constructors here.
10680 if (cast<CXXConstructorDecl>(Fn)->isCopyOrMoveConstructor())
10682 S.Diag(Fn->getLocation(),
10683 diag::note_ovl_candidate_inherited_constructor_slice)
10684 << (Fn->getPrimaryTemplate() ? 1 : 0)
10685 << Fn->getParamDecl(0)->getType()->isRValueReferenceType();
10686 MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
10689 case ovl_fail_addr_not_available: {
10690 bool Available = checkAddressOfCandidateIsAvailable(S, Cand->Function);
10692 assert(!Available);
10695 case ovl_non_default_multiversion_function:
10696 // Do nothing, these should simply be ignored.
10701 static void NoteSurrogateCandidate(Sema &S, OverloadCandidate *Cand) {
10702 // Desugar the type of the surrogate down to a function type,
10703 // retaining as many typedefs as possible while still showing
10704 // the function type (and, therefore, its parameter types).
10705 QualType FnType = Cand->Surrogate->getConversionType();
10706 bool isLValueReference = false;
10707 bool isRValueReference = false;
10708 bool isPointer = false;
10709 if (const LValueReferenceType *FnTypeRef =
10710 FnType->getAs<LValueReferenceType>()) {
10711 FnType = FnTypeRef->getPointeeType();
10712 isLValueReference = true;
10713 } else if (const RValueReferenceType *FnTypeRef =
10714 FnType->getAs<RValueReferenceType>()) {
10715 FnType = FnTypeRef->getPointeeType();
10716 isRValueReference = true;
10718 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) {
10719 FnType = FnTypePtr->getPointeeType();
10722 // Desugar down to a function type.
10723 FnType = QualType(FnType->getAs<FunctionType>(), 0);
10724 // Reconstruct the pointer/reference as appropriate.
10725 if (isPointer) FnType = S.Context.getPointerType(FnType);
10726 if (isRValueReference) FnType = S.Context.getRValueReferenceType(FnType);
10727 if (isLValueReference) FnType = S.Context.getLValueReferenceType(FnType);
10729 S.Diag(Cand->Surrogate->getLocation(), diag::note_ovl_surrogate_cand)
10733 static void NoteBuiltinOperatorCandidate(Sema &S, StringRef Opc,
10734 SourceLocation OpLoc,
10735 OverloadCandidate *Cand) {
10736 assert(Cand->Conversions.size() <= 2 && "builtin operator is not binary");
10737 std::string TypeStr("operator");
10740 TypeStr += Cand->BuiltinParamTypes[0].getAsString();
10741 if (Cand->Conversions.size() == 1) {
10743 S.Diag(OpLoc, diag::note_ovl_builtin_candidate) << TypeStr;
10746 TypeStr += Cand->BuiltinParamTypes[1].getAsString();
10748 S.Diag(OpLoc, diag::note_ovl_builtin_candidate) << TypeStr;
10752 static void NoteAmbiguousUserConversions(Sema &S, SourceLocation OpLoc,
10753 OverloadCandidate *Cand) {
10754 for (const ImplicitConversionSequence &ICS : Cand->Conversions) {
10755 if (ICS.isBad()) break; // all meaningless after first invalid
10756 if (!ICS.isAmbiguous()) continue;
10758 ICS.DiagnoseAmbiguousConversion(
10759 S, OpLoc, S.PDiag(diag::note_ambiguous_type_conversion));
10763 static SourceLocation GetLocationForCandidate(const OverloadCandidate *Cand) {
10764 if (Cand->Function)
10765 return Cand->Function->getLocation();
10766 if (Cand->IsSurrogate)
10767 return Cand->Surrogate->getLocation();
10768 return SourceLocation();
10771 static unsigned RankDeductionFailure(const DeductionFailureInfo &DFI) {
10772 switch ((Sema::TemplateDeductionResult)DFI.Result) {
10773 case Sema::TDK_Success:
10774 case Sema::TDK_NonDependentConversionFailure:
10775 llvm_unreachable("non-deduction failure while diagnosing bad deduction");
10777 case Sema::TDK_Invalid:
10778 case Sema::TDK_Incomplete:
10779 case Sema::TDK_IncompletePack:
10782 case Sema::TDK_Underqualified:
10783 case Sema::TDK_Inconsistent:
10786 case Sema::TDK_SubstitutionFailure:
10787 case Sema::TDK_DeducedMismatch:
10788 case Sema::TDK_DeducedMismatchNested:
10789 case Sema::TDK_NonDeducedMismatch:
10790 case Sema::TDK_MiscellaneousDeductionFailure:
10791 case Sema::TDK_CUDATargetMismatch:
10794 case Sema::TDK_InstantiationDepth:
10797 case Sema::TDK_InvalidExplicitArguments:
10800 case Sema::TDK_TooManyArguments:
10801 case Sema::TDK_TooFewArguments:
10804 llvm_unreachable("Unhandled deduction result");
10808 struct CompareOverloadCandidatesForDisplay {
10810 SourceLocation Loc;
10812 OverloadCandidateSet::CandidateSetKind CSK;
10814 CompareOverloadCandidatesForDisplay(
10815 Sema &S, SourceLocation Loc, size_t NArgs,
10816 OverloadCandidateSet::CandidateSetKind CSK)
10817 : S(S), NumArgs(NArgs), CSK(CSK) {}
10819 bool operator()(const OverloadCandidate *L,
10820 const OverloadCandidate *R) {
10821 // Fast-path this check.
10822 if (L == R) return false;
10824 // Order first by viability.
10826 if (!R->Viable) return true;
10828 // TODO: introduce a tri-valued comparison for overload
10829 // candidates. Would be more worthwhile if we had a sort
10830 // that could exploit it.
10831 if (isBetterOverloadCandidate(S, *L, *R, SourceLocation(), CSK))
10833 if (isBetterOverloadCandidate(S, *R, *L, SourceLocation(), CSK))
10835 } else if (R->Viable)
10838 assert(L->Viable == R->Viable);
10840 // Criteria by which we can sort non-viable candidates:
10842 // 1. Arity mismatches come after other candidates.
10843 if (L->FailureKind == ovl_fail_too_many_arguments ||
10844 L->FailureKind == ovl_fail_too_few_arguments) {
10845 if (R->FailureKind == ovl_fail_too_many_arguments ||
10846 R->FailureKind == ovl_fail_too_few_arguments) {
10847 int LDist = std::abs((int)L->getNumParams() - (int)NumArgs);
10848 int RDist = std::abs((int)R->getNumParams() - (int)NumArgs);
10849 if (LDist == RDist) {
10850 if (L->FailureKind == R->FailureKind)
10851 // Sort non-surrogates before surrogates.
10852 return !L->IsSurrogate && R->IsSurrogate;
10853 // Sort candidates requiring fewer parameters than there were
10854 // arguments given after candidates requiring more parameters
10855 // than there were arguments given.
10856 return L->FailureKind == ovl_fail_too_many_arguments;
10858 return LDist < RDist;
10862 if (R->FailureKind == ovl_fail_too_many_arguments ||
10863 R->FailureKind == ovl_fail_too_few_arguments)
10866 // 2. Bad conversions come first and are ordered by the number
10867 // of bad conversions and quality of good conversions.
10868 if (L->FailureKind == ovl_fail_bad_conversion) {
10869 if (R->FailureKind != ovl_fail_bad_conversion)
10872 // The conversion that can be fixed with a smaller number of changes,
10874 unsigned numLFixes = L->Fix.NumConversionsFixed;
10875 unsigned numRFixes = R->Fix.NumConversionsFixed;
10876 numLFixes = (numLFixes == 0) ? UINT_MAX : numLFixes;
10877 numRFixes = (numRFixes == 0) ? UINT_MAX : numRFixes;
10878 if (numLFixes != numRFixes) {
10879 return numLFixes < numRFixes;
10882 // If there's any ordering between the defined conversions...
10883 // FIXME: this might not be transitive.
10884 assert(L->Conversions.size() == R->Conversions.size());
10886 int leftBetter = 0;
10887 unsigned I = (L->IgnoreObjectArgument || R->IgnoreObjectArgument);
10888 for (unsigned E = L->Conversions.size(); I != E; ++I) {
10889 switch (CompareImplicitConversionSequences(S, Loc,
10891 R->Conversions[I])) {
10892 case ImplicitConversionSequence::Better:
10896 case ImplicitConversionSequence::Worse:
10900 case ImplicitConversionSequence::Indistinguishable:
10904 if (leftBetter > 0) return true;
10905 if (leftBetter < 0) return false;
10907 } else if (R->FailureKind == ovl_fail_bad_conversion)
10910 if (L->FailureKind == ovl_fail_bad_deduction) {
10911 if (R->FailureKind != ovl_fail_bad_deduction)
10914 if (L->DeductionFailure.Result != R->DeductionFailure.Result)
10915 return RankDeductionFailure(L->DeductionFailure)
10916 < RankDeductionFailure(R->DeductionFailure);
10917 } else if (R->FailureKind == ovl_fail_bad_deduction)
10923 // Sort everything else by location.
10924 SourceLocation LLoc = GetLocationForCandidate(L);
10925 SourceLocation RLoc = GetLocationForCandidate(R);
10927 // Put candidates without locations (e.g. builtins) at the end.
10928 if (LLoc.isInvalid()) return false;
10929 if (RLoc.isInvalid()) return true;
10931 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc);
10936 /// CompleteNonViableCandidate - Normally, overload resolution only
10937 /// computes up to the first bad conversion. Produces the FixIt set if
10940 CompleteNonViableCandidate(Sema &S, OverloadCandidate *Cand,
10941 ArrayRef<Expr *> Args,
10942 OverloadCandidateSet::CandidateSetKind CSK) {
10943 assert(!Cand->Viable);
10945 // Don't do anything on failures other than bad conversion.
10946 if (Cand->FailureKind != ovl_fail_bad_conversion) return;
10948 // We only want the FixIts if all the arguments can be corrected.
10949 bool Unfixable = false;
10950 // Use a implicit copy initialization to check conversion fixes.
10951 Cand->Fix.setConversionChecker(TryCopyInitialization);
10953 // Attempt to fix the bad conversion.
10954 unsigned ConvCount = Cand->Conversions.size();
10955 for (unsigned ConvIdx = (Cand->IgnoreObjectArgument ? 1 : 0); /**/;
10957 assert(ConvIdx != ConvCount && "no bad conversion in candidate");
10958 if (Cand->Conversions[ConvIdx].isInitialized() &&
10959 Cand->Conversions[ConvIdx].isBad()) {
10960 Unfixable = !Cand->TryToFixBadConversion(ConvIdx, S);
10965 // FIXME: this should probably be preserved from the overload
10966 // operation somehow.
10967 bool SuppressUserConversions = false;
10969 unsigned ConvIdx = 0;
10970 unsigned ArgIdx = 0;
10971 ArrayRef<QualType> ParamTypes;
10973 if (Cand->IsSurrogate) {
10975 = Cand->Surrogate->getConversionType().getNonReferenceType();
10976 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
10977 ConvType = ConvPtrType->getPointeeType();
10978 ParamTypes = ConvType->castAs<FunctionProtoType>()->getParamTypes();
10979 // Conversion 0 is 'this', which doesn't have a corresponding parameter.
10981 } else if (Cand->Function) {
10983 Cand->Function->getType()->castAs<FunctionProtoType>()->getParamTypes();
10984 if (isa<CXXMethodDecl>(Cand->Function) &&
10985 !isa<CXXConstructorDecl>(Cand->Function)) {
10986 // Conversion 0 is 'this', which doesn't have a corresponding parameter.
10988 if (CSK == OverloadCandidateSet::CSK_Operator)
10989 // Argument 0 is 'this', which doesn't have a corresponding parameter.
10993 // Builtin operator.
10994 assert(ConvCount <= 3);
10995 ParamTypes = Cand->BuiltinParamTypes;
10998 // Fill in the rest of the conversions.
10999 bool Reversed = Cand->RewriteKind & CRK_Reversed;
11000 for (unsigned ParamIdx = Reversed ? ParamTypes.size() - 1 : 0;
11001 ConvIdx != ConvCount;
11002 ++ConvIdx, ++ArgIdx, ParamIdx += (Reversed ? -1 : 1)) {
11003 if (Cand->Conversions[ConvIdx].isInitialized()) {
11004 // We've already checked this conversion.
11005 } else if (ArgIdx < ParamTypes.size()) {
11006 if (ParamTypes[ParamIdx]->isDependentType())
11007 Cand->Conversions[ConvIdx].setAsIdentityConversion(
11008 Args[ArgIdx]->getType());
11010 Cand->Conversions[ConvIdx] =
11011 TryCopyInitialization(S, Args[ArgIdx], ParamTypes[ParamIdx],
11012 SuppressUserConversions,
11013 /*InOverloadResolution=*/true,
11014 /*AllowObjCWritebackConversion=*/
11015 S.getLangOpts().ObjCAutoRefCount);
11016 // Store the FixIt in the candidate if it exists.
11017 if (!Unfixable && Cand->Conversions[ConvIdx].isBad())
11018 Unfixable = !Cand->TryToFixBadConversion(ConvIdx, S);
11021 Cand->Conversions[ConvIdx].setEllipsis();
11025 SmallVector<OverloadCandidate *, 32> OverloadCandidateSet::CompleteCandidates(
11026 Sema &S, OverloadCandidateDisplayKind OCD, ArrayRef<Expr *> Args,
11027 SourceLocation OpLoc,
11028 llvm::function_ref<bool(OverloadCandidate &)> Filter) {
11029 // Sort the candidates by viability and position. Sorting directly would
11030 // be prohibitive, so we make a set of pointers and sort those.
11031 SmallVector<OverloadCandidate*, 32> Cands;
11032 if (OCD == OCD_AllCandidates) Cands.reserve(size());
11033 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) {
11034 if (!Filter(*Cand))
11037 Cands.push_back(Cand);
11038 else if (OCD == OCD_AllCandidates) {
11039 CompleteNonViableCandidate(S, Cand, Args, Kind);
11040 if (Cand->Function || Cand->IsSurrogate)
11041 Cands.push_back(Cand);
11042 // Otherwise, this a non-viable builtin candidate. We do not, in general,
11043 // want to list every possible builtin candidate.
11048 Cands, CompareOverloadCandidatesForDisplay(S, OpLoc, Args.size(), Kind));
11053 /// When overload resolution fails, prints diagnostic messages containing the
11054 /// candidates in the candidate set.
11055 void OverloadCandidateSet::NoteCandidates(PartialDiagnosticAt PD,
11056 Sema &S, OverloadCandidateDisplayKind OCD, ArrayRef<Expr *> Args,
11057 StringRef Opc, SourceLocation OpLoc,
11058 llvm::function_ref<bool(OverloadCandidate &)> Filter) {
11060 auto Cands = CompleteCandidates(S, OCD, Args, OpLoc, Filter);
11062 S.Diag(PD.first, PD.second);
11064 NoteCandidates(S, Args, Cands, Opc, OpLoc);
11067 void OverloadCandidateSet::NoteCandidates(Sema &S, ArrayRef<Expr *> Args,
11068 ArrayRef<OverloadCandidate *> Cands,
11069 StringRef Opc, SourceLocation OpLoc) {
11070 bool ReportedAmbiguousConversions = false;
11072 const OverloadsShown ShowOverloads = S.Diags.getShowOverloads();
11073 unsigned CandsShown = 0;
11074 auto I = Cands.begin(), E = Cands.end();
11075 for (; I != E; ++I) {
11076 OverloadCandidate *Cand = *I;
11078 // Set an arbitrary limit on the number of candidate functions we'll spam
11079 // the user with. FIXME: This limit should depend on details of the
11081 if (CandsShown >= 4 && ShowOverloads == Ovl_Best) {
11086 if (Cand->Function)
11087 NoteFunctionCandidate(S, Cand, Args.size(),
11088 /*TakingCandidateAddress=*/false, DestAS);
11089 else if (Cand->IsSurrogate)
11090 NoteSurrogateCandidate(S, Cand);
11092 assert(Cand->Viable &&
11093 "Non-viable built-in candidates are not added to Cands.");
11094 // Generally we only see ambiguities including viable builtin
11095 // operators if overload resolution got screwed up by an
11096 // ambiguous user-defined conversion.
11098 // FIXME: It's quite possible for different conversions to see
11099 // different ambiguities, though.
11100 if (!ReportedAmbiguousConversions) {
11101 NoteAmbiguousUserConversions(S, OpLoc, Cand);
11102 ReportedAmbiguousConversions = true;
11105 // If this is a viable builtin, print it.
11106 NoteBuiltinOperatorCandidate(S, Opc, OpLoc, Cand);
11111 S.Diag(OpLoc, diag::note_ovl_too_many_candidates) << int(E - I);
11114 static SourceLocation
11115 GetLocationForCandidate(const TemplateSpecCandidate *Cand) {
11116 return Cand->Specialization ? Cand->Specialization->getLocation()
11117 : SourceLocation();
11121 struct CompareTemplateSpecCandidatesForDisplay {
11123 CompareTemplateSpecCandidatesForDisplay(Sema &S) : S(S) {}
11125 bool operator()(const TemplateSpecCandidate *L,
11126 const TemplateSpecCandidate *R) {
11127 // Fast-path this check.
11131 // Assuming that both candidates are not matches...
11133 // Sort by the ranking of deduction failures.
11134 if (L->DeductionFailure.Result != R->DeductionFailure.Result)
11135 return RankDeductionFailure(L->DeductionFailure) <
11136 RankDeductionFailure(R->DeductionFailure);
11138 // Sort everything else by location.
11139 SourceLocation LLoc = GetLocationForCandidate(L);
11140 SourceLocation RLoc = GetLocationForCandidate(R);
11142 // Put candidates without locations (e.g. builtins) at the end.
11143 if (LLoc.isInvalid())
11145 if (RLoc.isInvalid())
11148 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc);
11153 /// Diagnose a template argument deduction failure.
11154 /// We are treating these failures as overload failures due to bad
11156 void TemplateSpecCandidate::NoteDeductionFailure(Sema &S,
11157 bool ForTakingAddress) {
11158 DiagnoseBadDeduction(S, FoundDecl, Specialization, // pattern
11159 DeductionFailure, /*NumArgs=*/0, ForTakingAddress);
11162 void TemplateSpecCandidateSet::destroyCandidates() {
11163 for (iterator i = begin(), e = end(); i != e; ++i) {
11164 i->DeductionFailure.Destroy();
11168 void TemplateSpecCandidateSet::clear() {
11169 destroyCandidates();
11170 Candidates.clear();
11173 /// NoteCandidates - When no template specialization match is found, prints
11174 /// diagnostic messages containing the non-matching specializations that form
11175 /// the candidate set.
11176 /// This is analoguous to OverloadCandidateSet::NoteCandidates() with
11177 /// OCD == OCD_AllCandidates and Cand->Viable == false.
11178 void TemplateSpecCandidateSet::NoteCandidates(Sema &S, SourceLocation Loc) {
11179 // Sort the candidates by position (assuming no candidate is a match).
11180 // Sorting directly would be prohibitive, so we make a set of pointers
11182 SmallVector<TemplateSpecCandidate *, 32> Cands;
11183 Cands.reserve(size());
11184 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) {
11185 if (Cand->Specialization)
11186 Cands.push_back(Cand);
11187 // Otherwise, this is a non-matching builtin candidate. We do not,
11188 // in general, want to list every possible builtin candidate.
11191 llvm::sort(Cands, CompareTemplateSpecCandidatesForDisplay(S));
11193 // FIXME: Perhaps rename OverloadsShown and getShowOverloads()
11194 // for generalization purposes (?).
11195 const OverloadsShown ShowOverloads = S.Diags.getShowOverloads();
11197 SmallVectorImpl<TemplateSpecCandidate *>::iterator I, E;
11198 unsigned CandsShown = 0;
11199 for (I = Cands.begin(), E = Cands.end(); I != E; ++I) {
11200 TemplateSpecCandidate *Cand = *I;
11202 // Set an arbitrary limit on the number of candidates we'll spam
11203 // the user with. FIXME: This limit should depend on details of the
11205 if (CandsShown >= 4 && ShowOverloads == Ovl_Best)
11209 assert(Cand->Specialization &&
11210 "Non-matching built-in candidates are not added to Cands.");
11211 Cand->NoteDeductionFailure(S, ForTakingAddress);
11215 S.Diag(Loc, diag::note_ovl_too_many_candidates) << int(E - I);
11218 // [PossiblyAFunctionType] --> [Return]
11219 // NonFunctionType --> NonFunctionType
11221 // R (*)(A) --> R (A)
11222 // R (&)(A) --> R (A)
11223 // R (S::*)(A) --> R (A)
11224 QualType Sema::ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType) {
11225 QualType Ret = PossiblyAFunctionType;
11226 if (const PointerType *ToTypePtr =
11227 PossiblyAFunctionType->getAs<PointerType>())
11228 Ret = ToTypePtr->getPointeeType();
11229 else if (const ReferenceType *ToTypeRef =
11230 PossiblyAFunctionType->getAs<ReferenceType>())
11231 Ret = ToTypeRef->getPointeeType();
11232 else if (const MemberPointerType *MemTypePtr =
11233 PossiblyAFunctionType->getAs<MemberPointerType>())
11234 Ret = MemTypePtr->getPointeeType();
11236 Context.getCanonicalType(Ret).getUnqualifiedType();
11240 static bool completeFunctionType(Sema &S, FunctionDecl *FD, SourceLocation Loc,
11241 bool Complain = true) {
11242 if (S.getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
11243 S.DeduceReturnType(FD, Loc, Complain))
11246 auto *FPT = FD->getType()->castAs<FunctionProtoType>();
11247 if (S.getLangOpts().CPlusPlus17 &&
11248 isUnresolvedExceptionSpec(FPT->getExceptionSpecType()) &&
11249 !S.ResolveExceptionSpec(Loc, FPT))
11256 // A helper class to help with address of function resolution
11257 // - allows us to avoid passing around all those ugly parameters
11258 class AddressOfFunctionResolver {
11261 const QualType& TargetType;
11262 QualType TargetFunctionType; // Extracted function type from target type
11265 //DeclAccessPair& ResultFunctionAccessPair;
11266 ASTContext& Context;
11268 bool TargetTypeIsNonStaticMemberFunction;
11269 bool FoundNonTemplateFunction;
11270 bool StaticMemberFunctionFromBoundPointer;
11271 bool HasComplained;
11273 OverloadExpr::FindResult OvlExprInfo;
11274 OverloadExpr *OvlExpr;
11275 TemplateArgumentListInfo OvlExplicitTemplateArgs;
11276 SmallVector<std::pair<DeclAccessPair, FunctionDecl*>, 4> Matches;
11277 TemplateSpecCandidateSet FailedCandidates;
11280 AddressOfFunctionResolver(Sema &S, Expr *SourceExpr,
11281 const QualType &TargetType, bool Complain)
11282 : S(S), SourceExpr(SourceExpr), TargetType(TargetType),
11283 Complain(Complain), Context(S.getASTContext()),
11284 TargetTypeIsNonStaticMemberFunction(
11285 !!TargetType->getAs<MemberPointerType>()),
11286 FoundNonTemplateFunction(false),
11287 StaticMemberFunctionFromBoundPointer(false),
11288 HasComplained(false),
11289 OvlExprInfo(OverloadExpr::find(SourceExpr)),
11290 OvlExpr(OvlExprInfo.Expression),
11291 FailedCandidates(OvlExpr->getNameLoc(), /*ForTakingAddress=*/true) {
11292 ExtractUnqualifiedFunctionTypeFromTargetType();
11294 if (TargetFunctionType->isFunctionType()) {
11295 if (UnresolvedMemberExpr *UME = dyn_cast<UnresolvedMemberExpr>(OvlExpr))
11296 if (!UME->isImplicitAccess() &&
11297 !S.ResolveSingleFunctionTemplateSpecialization(UME))
11298 StaticMemberFunctionFromBoundPointer = true;
11299 } else if (OvlExpr->hasExplicitTemplateArgs()) {
11300 DeclAccessPair dap;
11301 if (FunctionDecl *Fn = S.ResolveSingleFunctionTemplateSpecialization(
11302 OvlExpr, false, &dap)) {
11303 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn))
11304 if (!Method->isStatic()) {
11305 // If the target type is a non-function type and the function found
11306 // is a non-static member function, pretend as if that was the
11307 // target, it's the only possible type to end up with.
11308 TargetTypeIsNonStaticMemberFunction = true;
11310 // And skip adding the function if its not in the proper form.
11311 // We'll diagnose this due to an empty set of functions.
11312 if (!OvlExprInfo.HasFormOfMemberPointer)
11316 Matches.push_back(std::make_pair(dap, Fn));
11321 if (OvlExpr->hasExplicitTemplateArgs())
11322 OvlExpr->copyTemplateArgumentsInto(OvlExplicitTemplateArgs);
11324 if (FindAllFunctionsThatMatchTargetTypeExactly()) {
11325 // C++ [over.over]p4:
11326 // If more than one function is selected, [...]
11327 if (Matches.size() > 1 && !eliminiateSuboptimalOverloadCandidates()) {
11328 if (FoundNonTemplateFunction)
11329 EliminateAllTemplateMatches();
11331 EliminateAllExceptMostSpecializedTemplate();
11335 if (S.getLangOpts().CUDA && Matches.size() > 1)
11336 EliminateSuboptimalCudaMatches();
11339 bool hasComplained() const { return HasComplained; }
11342 bool candidateHasExactlyCorrectType(const FunctionDecl *FD) {
11344 return Context.hasSameUnqualifiedType(TargetFunctionType, FD->getType()) ||
11345 S.IsFunctionConversion(FD->getType(), TargetFunctionType, Discard);
11348 /// \return true if A is considered a better overload candidate for the
11349 /// desired type than B.
11350 bool isBetterCandidate(const FunctionDecl *A, const FunctionDecl *B) {
11351 // If A doesn't have exactly the correct type, we don't want to classify it
11352 // as "better" than anything else. This way, the user is required to
11353 // disambiguate for us if there are multiple candidates and no exact match.
11354 return candidateHasExactlyCorrectType(A) &&
11355 (!candidateHasExactlyCorrectType(B) ||
11356 compareEnableIfAttrs(S, A, B) == Comparison::Better);
11359 /// \return true if we were able to eliminate all but one overload candidate,
11360 /// false otherwise.
11361 bool eliminiateSuboptimalOverloadCandidates() {
11362 // Same algorithm as overload resolution -- one pass to pick the "best",
11363 // another pass to be sure that nothing is better than the best.
11364 auto Best = Matches.begin();
11365 for (auto I = Matches.begin()+1, E = Matches.end(); I != E; ++I)
11366 if (isBetterCandidate(I->second, Best->second))
11369 const FunctionDecl *BestFn = Best->second;
11370 auto IsBestOrInferiorToBest = [this, BestFn](
11371 const std::pair<DeclAccessPair, FunctionDecl *> &Pair) {
11372 return BestFn == Pair.second || isBetterCandidate(BestFn, Pair.second);
11375 // Note: We explicitly leave Matches unmodified if there isn't a clear best
11376 // option, so we can potentially give the user a better error
11377 if (!llvm::all_of(Matches, IsBestOrInferiorToBest))
11379 Matches[0] = *Best;
11384 bool isTargetTypeAFunction() const {
11385 return TargetFunctionType->isFunctionType();
11388 // [ToType] [Return]
11390 // R (*)(A) --> R (A), IsNonStaticMemberFunction = false
11391 // R (&)(A) --> R (A), IsNonStaticMemberFunction = false
11392 // R (S::*)(A) --> R (A), IsNonStaticMemberFunction = true
11393 void inline ExtractUnqualifiedFunctionTypeFromTargetType() {
11394 TargetFunctionType = S.ExtractUnqualifiedFunctionType(TargetType);
11397 // return true if any matching specializations were found
11398 bool AddMatchingTemplateFunction(FunctionTemplateDecl* FunctionTemplate,
11399 const DeclAccessPair& CurAccessFunPair) {
11400 if (CXXMethodDecl *Method
11401 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) {
11402 // Skip non-static function templates when converting to pointer, and
11403 // static when converting to member pointer.
11404 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction)
11407 else if (TargetTypeIsNonStaticMemberFunction)
11410 // C++ [over.over]p2:
11411 // If the name is a function template, template argument deduction is
11412 // done (14.8.2.2), and if the argument deduction succeeds, the
11413 // resulting template argument list is used to generate a single
11414 // function template specialization, which is added to the set of
11415 // overloaded functions considered.
11416 FunctionDecl *Specialization = nullptr;
11417 TemplateDeductionInfo Info(FailedCandidates.getLocation());
11418 if (Sema::TemplateDeductionResult Result
11419 = S.DeduceTemplateArguments(FunctionTemplate,
11420 &OvlExplicitTemplateArgs,
11421 TargetFunctionType, Specialization,
11422 Info, /*IsAddressOfFunction*/true)) {
11423 // Make a note of the failed deduction for diagnostics.
11424 FailedCandidates.addCandidate()
11425 .set(CurAccessFunPair, FunctionTemplate->getTemplatedDecl(),
11426 MakeDeductionFailureInfo(Context, Result, Info));
11430 // Template argument deduction ensures that we have an exact match or
11431 // compatible pointer-to-function arguments that would be adjusted by ICS.
11432 // This function template specicalization works.
11433 assert(S.isSameOrCompatibleFunctionType(
11434 Context.getCanonicalType(Specialization->getType()),
11435 Context.getCanonicalType(TargetFunctionType)));
11437 if (!S.checkAddressOfFunctionIsAvailable(Specialization))
11440 Matches.push_back(std::make_pair(CurAccessFunPair, Specialization));
11444 bool AddMatchingNonTemplateFunction(NamedDecl* Fn,
11445 const DeclAccessPair& CurAccessFunPair) {
11446 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) {
11447 // Skip non-static functions when converting to pointer, and static
11448 // when converting to member pointer.
11449 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction)
11452 else if (TargetTypeIsNonStaticMemberFunction)
11455 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) {
11456 if (S.getLangOpts().CUDA)
11457 if (FunctionDecl *Caller = dyn_cast<FunctionDecl>(S.CurContext))
11458 if (!Caller->isImplicit() && !S.IsAllowedCUDACall(Caller, FunDecl))
11460 if (FunDecl->isMultiVersion()) {
11461 const auto *TA = FunDecl->getAttr<TargetAttr>();
11462 if (TA && !TA->isDefaultVersion())
11466 // If any candidate has a placeholder return type, trigger its deduction
11468 if (completeFunctionType(S, FunDecl, SourceExpr->getBeginLoc(),
11470 HasComplained |= Complain;
11474 if (!S.checkAddressOfFunctionIsAvailable(FunDecl))
11477 // If we're in C, we need to support types that aren't exactly identical.
11478 if (!S.getLangOpts().CPlusPlus ||
11479 candidateHasExactlyCorrectType(FunDecl)) {
11480 Matches.push_back(std::make_pair(
11481 CurAccessFunPair, cast<FunctionDecl>(FunDecl->getCanonicalDecl())));
11482 FoundNonTemplateFunction = true;
11490 bool FindAllFunctionsThatMatchTargetTypeExactly() {
11493 // If the overload expression doesn't have the form of a pointer to
11494 // member, don't try to convert it to a pointer-to-member type.
11495 if (IsInvalidFormOfPointerToMemberFunction())
11498 for (UnresolvedSetIterator I = OvlExpr->decls_begin(),
11499 E = OvlExpr->decls_end();
11501 // Look through any using declarations to find the underlying function.
11502 NamedDecl *Fn = (*I)->getUnderlyingDecl();
11504 // C++ [over.over]p3:
11505 // Non-member functions and static member functions match
11506 // targets of type "pointer-to-function" or "reference-to-function."
11507 // Nonstatic member functions match targets of
11508 // type "pointer-to-member-function."
11509 // Note that according to DR 247, the containing class does not matter.
11510 if (FunctionTemplateDecl *FunctionTemplate
11511 = dyn_cast<FunctionTemplateDecl>(Fn)) {
11512 if (AddMatchingTemplateFunction(FunctionTemplate, I.getPair()))
11515 // If we have explicit template arguments supplied, skip non-templates.
11516 else if (!OvlExpr->hasExplicitTemplateArgs() &&
11517 AddMatchingNonTemplateFunction(Fn, I.getPair()))
11520 assert(Ret || Matches.empty());
11524 void EliminateAllExceptMostSpecializedTemplate() {
11525 // [...] and any given function template specialization F1 is
11526 // eliminated if the set contains a second function template
11527 // specialization whose function template is more specialized
11528 // than the function template of F1 according to the partial
11529 // ordering rules of 14.5.5.2.
11531 // The algorithm specified above is quadratic. We instead use a
11532 // two-pass algorithm (similar to the one used to identify the
11533 // best viable function in an overload set) that identifies the
11534 // best function template (if it exists).
11536 UnresolvedSet<4> MatchesCopy; // TODO: avoid!
11537 for (unsigned I = 0, E = Matches.size(); I != E; ++I)
11538 MatchesCopy.addDecl(Matches[I].second, Matches[I].first.getAccess());
11540 // TODO: It looks like FailedCandidates does not serve much purpose
11541 // here, since the no_viable diagnostic has index 0.
11542 UnresolvedSetIterator Result = S.getMostSpecialized(
11543 MatchesCopy.begin(), MatchesCopy.end(), FailedCandidates,
11544 SourceExpr->getBeginLoc(), S.PDiag(),
11545 S.PDiag(diag::err_addr_ovl_ambiguous)
11546 << Matches[0].second->getDeclName(),
11547 S.PDiag(diag::note_ovl_candidate)
11548 << (unsigned)oc_function << (unsigned)ocs_described_template,
11549 Complain, TargetFunctionType);
11551 if (Result != MatchesCopy.end()) {
11552 // Make it the first and only element
11553 Matches[0].first = Matches[Result - MatchesCopy.begin()].first;
11554 Matches[0].second = cast<FunctionDecl>(*Result);
11557 HasComplained |= Complain;
11560 void EliminateAllTemplateMatches() {
11561 // [...] any function template specializations in the set are
11562 // eliminated if the set also contains a non-template function, [...]
11563 for (unsigned I = 0, N = Matches.size(); I != N; ) {
11564 if (Matches[I].second->getPrimaryTemplate() == nullptr)
11567 Matches[I] = Matches[--N];
11573 void EliminateSuboptimalCudaMatches() {
11574 S.EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(S.CurContext), Matches);
11578 void ComplainNoMatchesFound() const {
11579 assert(Matches.empty());
11580 S.Diag(OvlExpr->getBeginLoc(), diag::err_addr_ovl_no_viable)
11581 << OvlExpr->getName() << TargetFunctionType
11582 << OvlExpr->getSourceRange();
11583 if (FailedCandidates.empty())
11584 S.NoteAllOverloadCandidates(OvlExpr, TargetFunctionType,
11585 /*TakingAddress=*/true);
11587 // We have some deduction failure messages. Use them to diagnose
11588 // the function templates, and diagnose the non-template candidates
11590 for (UnresolvedSetIterator I = OvlExpr->decls_begin(),
11591 IEnd = OvlExpr->decls_end();
11593 if (FunctionDecl *Fun =
11594 dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()))
11595 if (!functionHasPassObjectSizeParams(Fun))
11596 S.NoteOverloadCandidate(*I, Fun, CRK_None, TargetFunctionType,
11597 /*TakingAddress=*/true);
11598 FailedCandidates.NoteCandidates(S, OvlExpr->getBeginLoc());
11602 bool IsInvalidFormOfPointerToMemberFunction() const {
11603 return TargetTypeIsNonStaticMemberFunction &&
11604 !OvlExprInfo.HasFormOfMemberPointer;
11607 void ComplainIsInvalidFormOfPointerToMemberFunction() const {
11608 // TODO: Should we condition this on whether any functions might
11609 // have matched, or is it more appropriate to do that in callers?
11610 // TODO: a fixit wouldn't hurt.
11611 S.Diag(OvlExpr->getNameLoc(), diag::err_addr_ovl_no_qualifier)
11612 << TargetType << OvlExpr->getSourceRange();
11615 bool IsStaticMemberFunctionFromBoundPointer() const {
11616 return StaticMemberFunctionFromBoundPointer;
11619 void ComplainIsStaticMemberFunctionFromBoundPointer() const {
11620 S.Diag(OvlExpr->getBeginLoc(),
11621 diag::err_invalid_form_pointer_member_function)
11622 << OvlExpr->getSourceRange();
11625 void ComplainOfInvalidConversion() const {
11626 S.Diag(OvlExpr->getBeginLoc(), diag::err_addr_ovl_not_func_ptrref)
11627 << OvlExpr->getName() << TargetType;
11630 void ComplainMultipleMatchesFound() const {
11631 assert(Matches.size() > 1);
11632 S.Diag(OvlExpr->getBeginLoc(), diag::err_addr_ovl_ambiguous)
11633 << OvlExpr->getName() << OvlExpr->getSourceRange();
11634 S.NoteAllOverloadCandidates(OvlExpr, TargetFunctionType,
11635 /*TakingAddress=*/true);
11638 bool hadMultipleCandidates() const { return (OvlExpr->getNumDecls() > 1); }
11640 int getNumMatches() const { return Matches.size(); }
11642 FunctionDecl* getMatchingFunctionDecl() const {
11643 if (Matches.size() != 1) return nullptr;
11644 return Matches[0].second;
11647 const DeclAccessPair* getMatchingFunctionAccessPair() const {
11648 if (Matches.size() != 1) return nullptr;
11649 return &Matches[0].first;
11654 /// ResolveAddressOfOverloadedFunction - Try to resolve the address of
11655 /// an overloaded function (C++ [over.over]), where @p From is an
11656 /// expression with overloaded function type and @p ToType is the type
11657 /// we're trying to resolve to. For example:
11663 /// int (*pfd)(double) = f; // selects f(double)
11666 /// This routine returns the resulting FunctionDecl if it could be
11667 /// resolved, and NULL otherwise. When @p Complain is true, this
11668 /// routine will emit diagnostics if there is an error.
11670 Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr,
11671 QualType TargetType,
11673 DeclAccessPair &FoundResult,
11674 bool *pHadMultipleCandidates) {
11675 assert(AddressOfExpr->getType() == Context.OverloadTy);
11677 AddressOfFunctionResolver Resolver(*this, AddressOfExpr, TargetType,
11679 int NumMatches = Resolver.getNumMatches();
11680 FunctionDecl *Fn = nullptr;
11681 bool ShouldComplain = Complain && !Resolver.hasComplained();
11682 if (NumMatches == 0 && ShouldComplain) {
11683 if (Resolver.IsInvalidFormOfPointerToMemberFunction())
11684 Resolver.ComplainIsInvalidFormOfPointerToMemberFunction();
11686 Resolver.ComplainNoMatchesFound();
11688 else if (NumMatches > 1 && ShouldComplain)
11689 Resolver.ComplainMultipleMatchesFound();
11690 else if (NumMatches == 1) {
11691 Fn = Resolver.getMatchingFunctionDecl();
11693 if (auto *FPT = Fn->getType()->getAs<FunctionProtoType>())
11694 ResolveExceptionSpec(AddressOfExpr->getExprLoc(), FPT);
11695 FoundResult = *Resolver.getMatchingFunctionAccessPair();
11697 if (Resolver.IsStaticMemberFunctionFromBoundPointer())
11698 Resolver.ComplainIsStaticMemberFunctionFromBoundPointer();
11700 CheckAddressOfMemberAccess(AddressOfExpr, FoundResult);
11704 if (pHadMultipleCandidates)
11705 *pHadMultipleCandidates = Resolver.hadMultipleCandidates();
11709 /// Given an expression that refers to an overloaded function, try to
11710 /// resolve that function to a single function that can have its address taken.
11711 /// This will modify `Pair` iff it returns non-null.
11713 /// This routine can only realistically succeed if all but one candidates in the
11714 /// overload set for SrcExpr cannot have their addresses taken.
11716 Sema::resolveAddressOfOnlyViableOverloadCandidate(Expr *E,
11717 DeclAccessPair &Pair) {
11718 OverloadExpr::FindResult R = OverloadExpr::find(E);
11719 OverloadExpr *Ovl = R.Expression;
11720 FunctionDecl *Result = nullptr;
11721 DeclAccessPair DAP;
11722 // Don't use the AddressOfResolver because we're specifically looking for
11723 // cases where we have one overload candidate that lacks
11724 // enable_if/pass_object_size/...
11725 for (auto I = Ovl->decls_begin(), E = Ovl->decls_end(); I != E; ++I) {
11726 auto *FD = dyn_cast<FunctionDecl>(I->getUnderlyingDecl());
11730 if (!checkAddressOfFunctionIsAvailable(FD))
11733 // We have more than one result; quit.
11745 /// Given an overloaded function, tries to turn it into a non-overloaded
11746 /// function reference using resolveAddressOfOnlyViableOverloadCandidate. This
11747 /// will perform access checks, diagnose the use of the resultant decl, and, if
11748 /// requested, potentially perform a function-to-pointer decay.
11750 /// Returns false if resolveAddressOfOnlyViableOverloadCandidate fails.
11751 /// Otherwise, returns true. This may emit diagnostics and return true.
11752 bool Sema::resolveAndFixAddressOfOnlyViableOverloadCandidate(
11753 ExprResult &SrcExpr, bool DoFunctionPointerConverion) {
11754 Expr *E = SrcExpr.get();
11755 assert(E->getType() == Context.OverloadTy && "SrcExpr must be an overload");
11757 DeclAccessPair DAP;
11758 FunctionDecl *Found = resolveAddressOfOnlyViableOverloadCandidate(E, DAP);
11759 if (!Found || Found->isCPUDispatchMultiVersion() ||
11760 Found->isCPUSpecificMultiVersion())
11763 // Emitting multiple diagnostics for a function that is both inaccessible and
11764 // unavailable is consistent with our behavior elsewhere. So, always check
11766 DiagnoseUseOfDecl(Found, E->getExprLoc());
11767 CheckAddressOfMemberAccess(E, DAP);
11768 Expr *Fixed = FixOverloadedFunctionReference(E, DAP, Found);
11769 if (DoFunctionPointerConverion && Fixed->getType()->isFunctionType())
11770 SrcExpr = DefaultFunctionArrayConversion(Fixed, /*Diagnose=*/false);
11776 /// Given an expression that refers to an overloaded function, try to
11777 /// resolve that overloaded function expression down to a single function.
11779 /// This routine can only resolve template-ids that refer to a single function
11780 /// template, where that template-id refers to a single template whose template
11781 /// arguments are either provided by the template-id or have defaults,
11782 /// as described in C++0x [temp.arg.explicit]p3.
11784 /// If no template-ids are found, no diagnostics are emitted and NULL is
11787 Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl,
11789 DeclAccessPair *FoundResult) {
11790 // C++ [over.over]p1:
11791 // [...] [Note: any redundant set of parentheses surrounding the
11792 // overloaded function name is ignored (5.1). ]
11793 // C++ [over.over]p1:
11794 // [...] The overloaded function name can be preceded by the &
11797 // If we didn't actually find any template-ids, we're done.
11798 if (!ovl->hasExplicitTemplateArgs())
11801 TemplateArgumentListInfo ExplicitTemplateArgs;
11802 ovl->copyTemplateArgumentsInto(ExplicitTemplateArgs);
11803 TemplateSpecCandidateSet FailedCandidates(ovl->getNameLoc());
11805 // Look through all of the overloaded functions, searching for one
11806 // whose type matches exactly.
11807 FunctionDecl *Matched = nullptr;
11808 for (UnresolvedSetIterator I = ovl->decls_begin(),
11809 E = ovl->decls_end(); I != E; ++I) {
11810 // C++0x [temp.arg.explicit]p3:
11811 // [...] In contexts where deduction is done and fails, or in contexts
11812 // where deduction is not done, if a template argument list is
11813 // specified and it, along with any default template arguments,
11814 // identifies a single function template specialization, then the
11815 // template-id is an lvalue for the function template specialization.
11816 FunctionTemplateDecl *FunctionTemplate
11817 = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl());
11819 // C++ [over.over]p2:
11820 // If the name is a function template, template argument deduction is
11821 // done (14.8.2.2), and if the argument deduction succeeds, the
11822 // resulting template argument list is used to generate a single
11823 // function template specialization, which is added to the set of
11824 // overloaded functions considered.
11825 FunctionDecl *Specialization = nullptr;
11826 TemplateDeductionInfo Info(FailedCandidates.getLocation());
11827 if (TemplateDeductionResult Result
11828 = DeduceTemplateArguments(FunctionTemplate, &ExplicitTemplateArgs,
11829 Specialization, Info,
11830 /*IsAddressOfFunction*/true)) {
11831 // Make a note of the failed deduction for diagnostics.
11832 // TODO: Actually use the failed-deduction info?
11833 FailedCandidates.addCandidate()
11834 .set(I.getPair(), FunctionTemplate->getTemplatedDecl(),
11835 MakeDeductionFailureInfo(Context, Result, Info));
11839 assert(Specialization && "no specialization and no error?");
11841 // Multiple matches; we can't resolve to a single declaration.
11844 Diag(ovl->getExprLoc(), diag::err_addr_ovl_ambiguous)
11846 NoteAllOverloadCandidates(ovl);
11851 Matched = Specialization;
11852 if (FoundResult) *FoundResult = I.getPair();
11856 completeFunctionType(*this, Matched, ovl->getExprLoc(), Complain))
11862 // Resolve and fix an overloaded expression that can be resolved
11863 // because it identifies a single function template specialization.
11865 // Last three arguments should only be supplied if Complain = true
11867 // Return true if it was logically possible to so resolve the
11868 // expression, regardless of whether or not it succeeded. Always
11869 // returns true if 'complain' is set.
11870 bool Sema::ResolveAndFixSingleFunctionTemplateSpecialization(
11871 ExprResult &SrcExpr, bool doFunctionPointerConverion,
11872 bool complain, SourceRange OpRangeForComplaining,
11873 QualType DestTypeForComplaining,
11874 unsigned DiagIDForComplaining) {
11875 assert(SrcExpr.get()->getType() == Context.OverloadTy);
11877 OverloadExpr::FindResult ovl = OverloadExpr::find(SrcExpr.get());
11879 DeclAccessPair found;
11880 ExprResult SingleFunctionExpression;
11881 if (FunctionDecl *fn = ResolveSingleFunctionTemplateSpecialization(
11882 ovl.Expression, /*complain*/ false, &found)) {
11883 if (DiagnoseUseOfDecl(fn, SrcExpr.get()->getBeginLoc())) {
11884 SrcExpr = ExprError();
11888 // It is only correct to resolve to an instance method if we're
11889 // resolving a form that's permitted to be a pointer to member.
11890 // Otherwise we'll end up making a bound member expression, which
11891 // is illegal in all the contexts we resolve like this.
11892 if (!ovl.HasFormOfMemberPointer &&
11893 isa<CXXMethodDecl>(fn) &&
11894 cast<CXXMethodDecl>(fn)->isInstance()) {
11895 if (!complain) return false;
11897 Diag(ovl.Expression->getExprLoc(),
11898 diag::err_bound_member_function)
11899 << 0 << ovl.Expression->getSourceRange();
11901 // TODO: I believe we only end up here if there's a mix of
11902 // static and non-static candidates (otherwise the expression
11903 // would have 'bound member' type, not 'overload' type).
11904 // Ideally we would note which candidate was chosen and why
11905 // the static candidates were rejected.
11906 SrcExpr = ExprError();
11910 // Fix the expression to refer to 'fn'.
11911 SingleFunctionExpression =
11912 FixOverloadedFunctionReference(SrcExpr.get(), found, fn);
11914 // If desired, do function-to-pointer decay.
11915 if (doFunctionPointerConverion) {
11916 SingleFunctionExpression =
11917 DefaultFunctionArrayLvalueConversion(SingleFunctionExpression.get());
11918 if (SingleFunctionExpression.isInvalid()) {
11919 SrcExpr = ExprError();
11925 if (!SingleFunctionExpression.isUsable()) {
11927 Diag(OpRangeForComplaining.getBegin(), DiagIDForComplaining)
11928 << ovl.Expression->getName()
11929 << DestTypeForComplaining
11930 << OpRangeForComplaining
11931 << ovl.Expression->getQualifierLoc().getSourceRange();
11932 NoteAllOverloadCandidates(SrcExpr.get());
11934 SrcExpr = ExprError();
11941 SrcExpr = SingleFunctionExpression;
11945 /// Add a single candidate to the overload set.
11946 static void AddOverloadedCallCandidate(Sema &S,
11947 DeclAccessPair FoundDecl,
11948 TemplateArgumentListInfo *ExplicitTemplateArgs,
11949 ArrayRef<Expr *> Args,
11950 OverloadCandidateSet &CandidateSet,
11951 bool PartialOverloading,
11953 NamedDecl *Callee = FoundDecl.getDecl();
11954 if (isa<UsingShadowDecl>(Callee))
11955 Callee = cast<UsingShadowDecl>(Callee)->getTargetDecl();
11957 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) {
11958 if (ExplicitTemplateArgs) {
11959 assert(!KnownValid && "Explicit template arguments?");
11962 // Prevent ill-formed function decls to be added as overload candidates.
11963 if (!dyn_cast<FunctionProtoType>(Func->getType()->getAs<FunctionType>()))
11966 S.AddOverloadCandidate(Func, FoundDecl, Args, CandidateSet,
11967 /*SuppressUserConversions=*/false,
11968 PartialOverloading);
11972 if (FunctionTemplateDecl *FuncTemplate
11973 = dyn_cast<FunctionTemplateDecl>(Callee)) {
11974 S.AddTemplateOverloadCandidate(FuncTemplate, FoundDecl,
11975 ExplicitTemplateArgs, Args, CandidateSet,
11976 /*SuppressUserConversions=*/false,
11977 PartialOverloading);
11981 assert(!KnownValid && "unhandled case in overloaded call candidate");
11984 /// Add the overload candidates named by callee and/or found by argument
11985 /// dependent lookup to the given overload set.
11986 void Sema::AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE,
11987 ArrayRef<Expr *> Args,
11988 OverloadCandidateSet &CandidateSet,
11989 bool PartialOverloading) {
11992 // Verify that ArgumentDependentLookup is consistent with the rules
11993 // in C++0x [basic.lookup.argdep]p3:
11995 // Let X be the lookup set produced by unqualified lookup (3.4.1)
11996 // and let Y be the lookup set produced by argument dependent
11997 // lookup (defined as follows). If X contains
11999 // -- a declaration of a class member, or
12001 // -- a block-scope function declaration that is not a
12002 // using-declaration, or
12004 // -- a declaration that is neither a function or a function
12007 // then Y is empty.
12009 if (ULE->requiresADL()) {
12010 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(),
12011 E = ULE->decls_end(); I != E; ++I) {
12012 assert(!(*I)->getDeclContext()->isRecord());
12013 assert(isa<UsingShadowDecl>(*I) ||
12014 !(*I)->getDeclContext()->isFunctionOrMethod());
12015 assert((*I)->getUnderlyingDecl()->isFunctionOrFunctionTemplate());
12020 // It would be nice to avoid this copy.
12021 TemplateArgumentListInfo TABuffer;
12022 TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr;
12023 if (ULE->hasExplicitTemplateArgs()) {
12024 ULE->copyTemplateArgumentsInto(TABuffer);
12025 ExplicitTemplateArgs = &TABuffer;
12028 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(),
12029 E = ULE->decls_end(); I != E; ++I)
12030 AddOverloadedCallCandidate(*this, I.getPair(), ExplicitTemplateArgs, Args,
12031 CandidateSet, PartialOverloading,
12032 /*KnownValid*/ true);
12034 if (ULE->requiresADL())
12035 AddArgumentDependentLookupCandidates(ULE->getName(), ULE->getExprLoc(),
12036 Args, ExplicitTemplateArgs,
12037 CandidateSet, PartialOverloading);
12040 /// Determine whether a declaration with the specified name could be moved into
12041 /// a different namespace.
12042 static bool canBeDeclaredInNamespace(const DeclarationName &Name) {
12043 switch (Name.getCXXOverloadedOperator()) {
12044 case OO_New: case OO_Array_New:
12045 case OO_Delete: case OO_Array_Delete:
12053 /// Attempt to recover from an ill-formed use of a non-dependent name in a
12054 /// template, where the non-dependent name was declared after the template
12055 /// was defined. This is common in code written for a compilers which do not
12056 /// correctly implement two-stage name lookup.
12058 /// Returns true if a viable candidate was found and a diagnostic was issued.
12060 DiagnoseTwoPhaseLookup(Sema &SemaRef, SourceLocation FnLoc,
12061 const CXXScopeSpec &SS, LookupResult &R,
12062 OverloadCandidateSet::CandidateSetKind CSK,
12063 TemplateArgumentListInfo *ExplicitTemplateArgs,
12064 ArrayRef<Expr *> Args,
12065 bool *DoDiagnoseEmptyLookup = nullptr) {
12066 if (!SemaRef.inTemplateInstantiation() || !SS.isEmpty())
12069 for (DeclContext *DC = SemaRef.CurContext; DC; DC = DC->getParent()) {
12070 if (DC->isTransparentContext())
12073 SemaRef.LookupQualifiedName(R, DC);
12076 R.suppressDiagnostics();
12078 if (isa<CXXRecordDecl>(DC)) {
12079 // Don't diagnose names we find in classes; we get much better
12080 // diagnostics for these from DiagnoseEmptyLookup.
12082 if (DoDiagnoseEmptyLookup)
12083 *DoDiagnoseEmptyLookup = true;
12087 OverloadCandidateSet Candidates(FnLoc, CSK);
12088 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
12089 AddOverloadedCallCandidate(SemaRef, I.getPair(),
12090 ExplicitTemplateArgs, Args,
12091 Candidates, false, /*KnownValid*/ false);
12093 OverloadCandidateSet::iterator Best;
12094 if (Candidates.BestViableFunction(SemaRef, FnLoc, Best) != OR_Success) {
12095 // No viable functions. Don't bother the user with notes for functions
12096 // which don't work and shouldn't be found anyway.
12101 // Find the namespaces where ADL would have looked, and suggest
12102 // declaring the function there instead.
12103 Sema::AssociatedNamespaceSet AssociatedNamespaces;
12104 Sema::AssociatedClassSet AssociatedClasses;
12105 SemaRef.FindAssociatedClassesAndNamespaces(FnLoc, Args,
12106 AssociatedNamespaces,
12107 AssociatedClasses);
12108 Sema::AssociatedNamespaceSet SuggestedNamespaces;
12109 if (canBeDeclaredInNamespace(R.getLookupName())) {
12110 DeclContext *Std = SemaRef.getStdNamespace();
12111 for (Sema::AssociatedNamespaceSet::iterator
12112 it = AssociatedNamespaces.begin(),
12113 end = AssociatedNamespaces.end(); it != end; ++it) {
12114 // Never suggest declaring a function within namespace 'std'.
12115 if (Std && Std->Encloses(*it))
12118 // Never suggest declaring a function within a namespace with a
12119 // reserved name, like __gnu_cxx.
12120 NamespaceDecl *NS = dyn_cast<NamespaceDecl>(*it);
12122 NS->getQualifiedNameAsString().find("__") != std::string::npos)
12125 SuggestedNamespaces.insert(*it);
12129 SemaRef.Diag(R.getNameLoc(), diag::err_not_found_by_two_phase_lookup)
12130 << R.getLookupName();
12131 if (SuggestedNamespaces.empty()) {
12132 SemaRef.Diag(Best->Function->getLocation(),
12133 diag::note_not_found_by_two_phase_lookup)
12134 << R.getLookupName() << 0;
12135 } else if (SuggestedNamespaces.size() == 1) {
12136 SemaRef.Diag(Best->Function->getLocation(),
12137 diag::note_not_found_by_two_phase_lookup)
12138 << R.getLookupName() << 1 << *SuggestedNamespaces.begin();
12140 // FIXME: It would be useful to list the associated namespaces here,
12141 // but the diagnostics infrastructure doesn't provide a way to produce
12142 // a localized representation of a list of items.
12143 SemaRef.Diag(Best->Function->getLocation(),
12144 diag::note_not_found_by_two_phase_lookup)
12145 << R.getLookupName() << 2;
12148 // Try to recover by calling this function.
12158 /// Attempt to recover from ill-formed use of a non-dependent operator in a
12159 /// template, where the non-dependent operator was declared after the template
12162 /// Returns true if a viable candidate was found and a diagnostic was issued.
12164 DiagnoseTwoPhaseOperatorLookup(Sema &SemaRef, OverloadedOperatorKind Op,
12165 SourceLocation OpLoc,
12166 ArrayRef<Expr *> Args) {
12167 DeclarationName OpName =
12168 SemaRef.Context.DeclarationNames.getCXXOperatorName(Op);
12169 LookupResult R(SemaRef, OpName, OpLoc, Sema::LookupOperatorName);
12170 return DiagnoseTwoPhaseLookup(SemaRef, OpLoc, CXXScopeSpec(), R,
12171 OverloadCandidateSet::CSK_Operator,
12172 /*ExplicitTemplateArgs=*/nullptr, Args);
12176 class BuildRecoveryCallExprRAII {
12179 BuildRecoveryCallExprRAII(Sema &S) : SemaRef(S) {
12180 assert(SemaRef.IsBuildingRecoveryCallExpr == false);
12181 SemaRef.IsBuildingRecoveryCallExpr = true;
12184 ~BuildRecoveryCallExprRAII() {
12185 SemaRef.IsBuildingRecoveryCallExpr = false;
12191 /// Attempts to recover from a call where no functions were found.
12193 /// Returns true if new candidates were found.
12195 BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn,
12196 UnresolvedLookupExpr *ULE,
12197 SourceLocation LParenLoc,
12198 MutableArrayRef<Expr *> Args,
12199 SourceLocation RParenLoc,
12200 bool EmptyLookup, bool AllowTypoCorrection) {
12201 // Do not try to recover if it is already building a recovery call.
12202 // This stops infinite loops for template instantiations like
12204 // template <typename T> auto foo(T t) -> decltype(foo(t)) {}
12205 // template <typename T> auto foo(T t) -> decltype(foo(&t)) {}
12207 if (SemaRef.IsBuildingRecoveryCallExpr)
12208 return ExprError();
12209 BuildRecoveryCallExprRAII RCE(SemaRef);
12212 SS.Adopt(ULE->getQualifierLoc());
12213 SourceLocation TemplateKWLoc = ULE->getTemplateKeywordLoc();
12215 TemplateArgumentListInfo TABuffer;
12216 TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr;
12217 if (ULE->hasExplicitTemplateArgs()) {
12218 ULE->copyTemplateArgumentsInto(TABuffer);
12219 ExplicitTemplateArgs = &TABuffer;
12222 LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(),
12223 Sema::LookupOrdinaryName);
12224 bool DoDiagnoseEmptyLookup = EmptyLookup;
12225 if (!DiagnoseTwoPhaseLookup(
12226 SemaRef, Fn->getExprLoc(), SS, R, OverloadCandidateSet::CSK_Normal,
12227 ExplicitTemplateArgs, Args, &DoDiagnoseEmptyLookup)) {
12228 NoTypoCorrectionCCC NoTypoValidator{};
12229 FunctionCallFilterCCC FunctionCallValidator(SemaRef, Args.size(),
12230 ExplicitTemplateArgs != nullptr,
12231 dyn_cast<MemberExpr>(Fn));
12232 CorrectionCandidateCallback &Validator =
12233 AllowTypoCorrection
12234 ? static_cast<CorrectionCandidateCallback &>(FunctionCallValidator)
12235 : static_cast<CorrectionCandidateCallback &>(NoTypoValidator);
12236 if (!DoDiagnoseEmptyLookup ||
12237 SemaRef.DiagnoseEmptyLookup(S, SS, R, Validator, ExplicitTemplateArgs,
12239 return ExprError();
12242 assert(!R.empty() && "lookup results empty despite recovery");
12244 // If recovery created an ambiguity, just bail out.
12245 if (R.isAmbiguous()) {
12246 R.suppressDiagnostics();
12247 return ExprError();
12250 // Build an implicit member call if appropriate. Just drop the
12251 // casts and such from the call, we don't really care.
12252 ExprResult NewFn = ExprError();
12253 if ((*R.begin())->isCXXClassMember())
12254 NewFn = SemaRef.BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc, R,
12255 ExplicitTemplateArgs, S);
12256 else if (ExplicitTemplateArgs || TemplateKWLoc.isValid())
12257 NewFn = SemaRef.BuildTemplateIdExpr(SS, TemplateKWLoc, R, false,
12258 ExplicitTemplateArgs);
12260 NewFn = SemaRef.BuildDeclarationNameExpr(SS, R, false);
12262 if (NewFn.isInvalid())
12263 return ExprError();
12265 // This shouldn't cause an infinite loop because we're giving it
12266 // an expression with viable lookup results, which should never
12268 return SemaRef.BuildCallExpr(/*Scope*/ nullptr, NewFn.get(), LParenLoc,
12269 MultiExprArg(Args.data(), Args.size()),
12273 /// Constructs and populates an OverloadedCandidateSet from
12274 /// the given function.
12275 /// \returns true when an the ExprResult output parameter has been set.
12276 bool Sema::buildOverloadedCallSet(Scope *S, Expr *Fn,
12277 UnresolvedLookupExpr *ULE,
12279 SourceLocation RParenLoc,
12280 OverloadCandidateSet *CandidateSet,
12281 ExprResult *Result) {
12283 if (ULE->requiresADL()) {
12284 // To do ADL, we must have found an unqualified name.
12285 assert(!ULE->getQualifier() && "qualified name with ADL");
12287 // We don't perform ADL for implicit declarations of builtins.
12288 // Verify that this was correctly set up.
12290 if (ULE->decls_begin() != ULE->decls_end() &&
12291 ULE->decls_begin() + 1 == ULE->decls_end() &&
12292 (F = dyn_cast<FunctionDecl>(*ULE->decls_begin())) &&
12293 F->getBuiltinID() && F->isImplicit())
12294 llvm_unreachable("performing ADL for builtin");
12296 // We don't perform ADL in C.
12297 assert(getLangOpts().CPlusPlus && "ADL enabled in C");
12301 UnbridgedCastsSet UnbridgedCasts;
12302 if (checkArgPlaceholdersForOverload(*this, Args, UnbridgedCasts)) {
12303 *Result = ExprError();
12307 // Add the functions denoted by the callee to the set of candidate
12308 // functions, including those from argument-dependent lookup.
12309 AddOverloadedCallCandidates(ULE, Args, *CandidateSet);
12311 if (getLangOpts().MSVCCompat &&
12312 CurContext->isDependentContext() && !isSFINAEContext() &&
12313 (isa<FunctionDecl>(CurContext) || isa<CXXRecordDecl>(CurContext))) {
12315 OverloadCandidateSet::iterator Best;
12316 if (CandidateSet->empty() ||
12317 CandidateSet->BestViableFunction(*this, Fn->getBeginLoc(), Best) ==
12318 OR_No_Viable_Function) {
12319 // In Microsoft mode, if we are inside a template class member function
12320 // then create a type dependent CallExpr. The goal is to postpone name
12321 // lookup to instantiation time to be able to search into type dependent
12323 CallExpr *CE = CallExpr::Create(Context, Fn, Args, Context.DependentTy,
12324 VK_RValue, RParenLoc);
12325 CE->setTypeDependent(true);
12326 CE->setValueDependent(true);
12327 CE->setInstantiationDependent(true);
12333 if (CandidateSet->empty())
12336 UnbridgedCasts.restore();
12340 /// FinishOverloadedCallExpr - given an OverloadCandidateSet, builds and returns
12341 /// the completed call expression. If overload resolution fails, emits
12342 /// diagnostics and returns ExprError()
12343 static ExprResult FinishOverloadedCallExpr(Sema &SemaRef, Scope *S, Expr *Fn,
12344 UnresolvedLookupExpr *ULE,
12345 SourceLocation LParenLoc,
12347 SourceLocation RParenLoc,
12349 OverloadCandidateSet *CandidateSet,
12350 OverloadCandidateSet::iterator *Best,
12351 OverloadingResult OverloadResult,
12352 bool AllowTypoCorrection) {
12353 if (CandidateSet->empty())
12354 return BuildRecoveryCallExpr(SemaRef, S, Fn, ULE, LParenLoc, Args,
12355 RParenLoc, /*EmptyLookup=*/true,
12356 AllowTypoCorrection);
12358 switch (OverloadResult) {
12360 FunctionDecl *FDecl = (*Best)->Function;
12361 SemaRef.CheckUnresolvedLookupAccess(ULE, (*Best)->FoundDecl);
12362 if (SemaRef.DiagnoseUseOfDecl(FDecl, ULE->getNameLoc()))
12363 return ExprError();
12364 Fn = SemaRef.FixOverloadedFunctionReference(Fn, (*Best)->FoundDecl, FDecl);
12365 return SemaRef.BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, RParenLoc,
12366 ExecConfig, /*IsExecConfig=*/false,
12367 (*Best)->IsADLCandidate);
12370 case OR_No_Viable_Function: {
12371 // Try to recover by looking for viable functions which the user might
12372 // have meant to call.
12373 ExprResult Recovery = BuildRecoveryCallExpr(SemaRef, S, Fn, ULE, LParenLoc,
12375 /*EmptyLookup=*/false,
12376 AllowTypoCorrection);
12377 if (!Recovery.isInvalid())
12380 // If the user passes in a function that we can't take the address of, we
12381 // generally end up emitting really bad error messages. Here, we attempt to
12382 // emit better ones.
12383 for (const Expr *Arg : Args) {
12384 if (!Arg->getType()->isFunctionType())
12386 if (auto *DRE = dyn_cast<DeclRefExpr>(Arg->IgnoreParenImpCasts())) {
12387 auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
12389 !SemaRef.checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
12390 Arg->getExprLoc()))
12391 return ExprError();
12395 CandidateSet->NoteCandidates(
12396 PartialDiagnosticAt(
12398 SemaRef.PDiag(diag::err_ovl_no_viable_function_in_call)
12399 << ULE->getName() << Fn->getSourceRange()),
12400 SemaRef, OCD_AllCandidates, Args);
12405 CandidateSet->NoteCandidates(
12406 PartialDiagnosticAt(Fn->getBeginLoc(),
12407 SemaRef.PDiag(diag::err_ovl_ambiguous_call)
12408 << ULE->getName() << Fn->getSourceRange()),
12409 SemaRef, OCD_ViableCandidates, Args);
12413 CandidateSet->NoteCandidates(
12414 PartialDiagnosticAt(Fn->getBeginLoc(),
12415 SemaRef.PDiag(diag::err_ovl_deleted_call)
12416 << ULE->getName() << Fn->getSourceRange()),
12417 SemaRef, OCD_AllCandidates, Args);
12419 // We emitted an error for the unavailable/deleted function call but keep
12420 // the call in the AST.
12421 FunctionDecl *FDecl = (*Best)->Function;
12422 Fn = SemaRef.FixOverloadedFunctionReference(Fn, (*Best)->FoundDecl, FDecl);
12423 return SemaRef.BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, RParenLoc,
12424 ExecConfig, /*IsExecConfig=*/false,
12425 (*Best)->IsADLCandidate);
12429 // Overload resolution failed.
12430 return ExprError();
12433 static void markUnaddressableCandidatesUnviable(Sema &S,
12434 OverloadCandidateSet &CS) {
12435 for (auto I = CS.begin(), E = CS.end(); I != E; ++I) {
12437 !S.checkAddressOfFunctionIsAvailable(I->Function, /*Complain=*/false)) {
12439 I->FailureKind = ovl_fail_addr_not_available;
12444 /// BuildOverloadedCallExpr - Given the call expression that calls Fn
12445 /// (which eventually refers to the declaration Func) and the call
12446 /// arguments Args/NumArgs, attempt to resolve the function call down
12447 /// to a specific function. If overload resolution succeeds, returns
12448 /// the call expression produced by overload resolution.
12449 /// Otherwise, emits diagnostics and returns ExprError.
12450 ExprResult Sema::BuildOverloadedCallExpr(Scope *S, Expr *Fn,
12451 UnresolvedLookupExpr *ULE,
12452 SourceLocation LParenLoc,
12454 SourceLocation RParenLoc,
12456 bool AllowTypoCorrection,
12457 bool CalleesAddressIsTaken) {
12458 OverloadCandidateSet CandidateSet(Fn->getExprLoc(),
12459 OverloadCandidateSet::CSK_Normal);
12462 if (buildOverloadedCallSet(S, Fn, ULE, Args, LParenLoc, &CandidateSet,
12466 // If the user handed us something like `(&Foo)(Bar)`, we need to ensure that
12467 // functions that aren't addressible are considered unviable.
12468 if (CalleesAddressIsTaken)
12469 markUnaddressableCandidatesUnviable(*this, CandidateSet);
12471 OverloadCandidateSet::iterator Best;
12472 OverloadingResult OverloadResult =
12473 CandidateSet.BestViableFunction(*this, Fn->getBeginLoc(), Best);
12475 return FinishOverloadedCallExpr(*this, S, Fn, ULE, LParenLoc, Args, RParenLoc,
12476 ExecConfig, &CandidateSet, &Best,
12477 OverloadResult, AllowTypoCorrection);
12480 static bool IsOverloaded(const UnresolvedSetImpl &Functions) {
12481 return Functions.size() > 1 ||
12482 (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin()));
12485 /// Create a unary operation that may resolve to an overloaded
12488 /// \param OpLoc The location of the operator itself (e.g., '*').
12490 /// \param Opc The UnaryOperatorKind that describes this operator.
12492 /// \param Fns The set of non-member functions that will be
12493 /// considered by overload resolution. The caller needs to build this
12494 /// set based on the context using, e.g.,
12495 /// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This
12496 /// set should not contain any member functions; those will be added
12497 /// by CreateOverloadedUnaryOp().
12499 /// \param Input The input argument.
12501 Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, UnaryOperatorKind Opc,
12502 const UnresolvedSetImpl &Fns,
12503 Expr *Input, bool PerformADL) {
12504 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc);
12505 assert(Op != OO_None && "Invalid opcode for overloaded unary operator");
12506 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op);
12507 // TODO: provide better source location info.
12508 DeclarationNameInfo OpNameInfo(OpName, OpLoc);
12510 if (checkPlaceholderForOverload(*this, Input))
12511 return ExprError();
12513 Expr *Args[2] = { Input, nullptr };
12514 unsigned NumArgs = 1;
12516 // For post-increment and post-decrement, add the implicit '0' as
12517 // the second argument, so that we know this is a post-increment or
12519 if (Opc == UO_PostInc || Opc == UO_PostDec) {
12520 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false);
12521 Args[1] = IntegerLiteral::Create(Context, Zero, Context.IntTy,
12526 ArrayRef<Expr *> ArgsArray(Args, NumArgs);
12528 if (Input->isTypeDependent()) {
12530 return new (Context) UnaryOperator(Input, Opc, Context.DependentTy,
12531 VK_RValue, OK_Ordinary, OpLoc, false);
12533 CXXRecordDecl *NamingClass = nullptr; // lookup ignores member operators
12534 UnresolvedLookupExpr *Fn = UnresolvedLookupExpr::Create(
12535 Context, NamingClass, NestedNameSpecifierLoc(), OpNameInfo,
12536 /*ADL*/ true, IsOverloaded(Fns), Fns.begin(), Fns.end());
12537 return CXXOperatorCallExpr::Create(Context, Op, Fn, ArgsArray,
12538 Context.DependentTy, VK_RValue, OpLoc,
12542 // Build an empty overload set.
12543 OverloadCandidateSet CandidateSet(OpLoc, OverloadCandidateSet::CSK_Operator);
12545 // Add the candidates from the given function set.
12546 AddNonMemberOperatorCandidates(Fns, ArgsArray, CandidateSet);
12548 // Add operator candidates that are member functions.
12549 AddMemberOperatorCandidates(Op, OpLoc, ArgsArray, CandidateSet);
12551 // Add candidates from ADL.
12553 AddArgumentDependentLookupCandidates(OpName, OpLoc, ArgsArray,
12554 /*ExplicitTemplateArgs*/nullptr,
12558 // Add builtin operator candidates.
12559 AddBuiltinOperatorCandidates(Op, OpLoc, ArgsArray, CandidateSet);
12561 bool HadMultipleCandidates = (CandidateSet.size() > 1);
12563 // Perform overload resolution.
12564 OverloadCandidateSet::iterator Best;
12565 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) {
12567 // We found a built-in operator or an overloaded operator.
12568 FunctionDecl *FnDecl = Best->Function;
12571 Expr *Base = nullptr;
12572 // We matched an overloaded operator. Build a call to that
12575 // Convert the arguments.
12576 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) {
12577 CheckMemberOperatorAccess(OpLoc, Args[0], nullptr, Best->FoundDecl);
12579 ExprResult InputRes =
12580 PerformObjectArgumentInitialization(Input, /*Qualifier=*/nullptr,
12581 Best->FoundDecl, Method);
12582 if (InputRes.isInvalid())
12583 return ExprError();
12584 Base = Input = InputRes.get();
12586 // Convert the arguments.
12587 ExprResult InputInit
12588 = PerformCopyInitialization(InitializedEntity::InitializeParameter(
12590 FnDecl->getParamDecl(0)),
12593 if (InputInit.isInvalid())
12594 return ExprError();
12595 Input = InputInit.get();
12598 // Build the actual expression node.
12599 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, Best->FoundDecl,
12600 Base, HadMultipleCandidates,
12602 if (FnExpr.isInvalid())
12603 return ExprError();
12605 // Determine the result type.
12606 QualType ResultTy = FnDecl->getReturnType();
12607 ExprValueKind VK = Expr::getValueKindForType(ResultTy);
12608 ResultTy = ResultTy.getNonLValueExprType(Context);
12611 CallExpr *TheCall = CXXOperatorCallExpr::Create(
12612 Context, Op, FnExpr.get(), ArgsArray, ResultTy, VK, OpLoc,
12613 FPOptions(), Best->IsADLCandidate);
12615 if (CheckCallReturnType(FnDecl->getReturnType(), OpLoc, TheCall, FnDecl))
12616 return ExprError();
12618 if (CheckFunctionCall(FnDecl, TheCall,
12619 FnDecl->getType()->castAs<FunctionProtoType>()))
12620 return ExprError();
12622 return MaybeBindToTemporary(TheCall);
12624 // We matched a built-in operator. Convert the arguments, then
12625 // break out so that we will build the appropriate built-in
12627 ExprResult InputRes = PerformImplicitConversion(
12628 Input, Best->BuiltinParamTypes[0], Best->Conversions[0], AA_Passing,
12629 CCK_ForBuiltinOverloadedOp);
12630 if (InputRes.isInvalid())
12631 return ExprError();
12632 Input = InputRes.get();
12637 case OR_No_Viable_Function:
12638 // This is an erroneous use of an operator which can be overloaded by
12639 // a non-member function. Check for non-member operators which were
12640 // defined too late to be candidates.
12641 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, ArgsArray))
12642 // FIXME: Recover by calling the found function.
12643 return ExprError();
12645 // No viable function; fall through to handling this as a
12646 // built-in operator, which will produce an error message for us.
12650 CandidateSet.NoteCandidates(
12651 PartialDiagnosticAt(OpLoc,
12652 PDiag(diag::err_ovl_ambiguous_oper_unary)
12653 << UnaryOperator::getOpcodeStr(Opc)
12654 << Input->getType() << Input->getSourceRange()),
12655 *this, OCD_ViableCandidates, ArgsArray,
12656 UnaryOperator::getOpcodeStr(Opc), OpLoc);
12657 return ExprError();
12660 CandidateSet.NoteCandidates(
12661 PartialDiagnosticAt(OpLoc, PDiag(diag::err_ovl_deleted_oper)
12662 << UnaryOperator::getOpcodeStr(Opc)
12663 << Input->getSourceRange()),
12664 *this, OCD_AllCandidates, ArgsArray, UnaryOperator::getOpcodeStr(Opc),
12666 return ExprError();
12669 // Either we found no viable overloaded operator or we matched a
12670 // built-in operator. In either case, fall through to trying to
12671 // build a built-in operation.
12672 return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
12675 /// Create a binary operation that may resolve to an overloaded
12678 /// \param OpLoc The location of the operator itself (e.g., '+').
12680 /// \param Opc The BinaryOperatorKind that describes this operator.
12682 /// \param Fns The set of non-member functions that will be
12683 /// considered by overload resolution. The caller needs to build this
12684 /// set based on the context using, e.g.,
12685 /// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This
12686 /// set should not contain any member functions; those will be added
12687 /// by CreateOverloadedBinOp().
12689 /// \param LHS Left-hand argument.
12690 /// \param RHS Right-hand argument.
12691 ExprResult Sema::CreateOverloadedBinOp(SourceLocation OpLoc,
12692 BinaryOperatorKind Opc,
12693 const UnresolvedSetImpl &Fns, Expr *LHS,
12694 Expr *RHS, bool PerformADL,
12695 bool AllowRewrittenCandidates) {
12696 Expr *Args[2] = { LHS, RHS };
12697 LHS=RHS=nullptr; // Please use only Args instead of LHS/RHS couple
12699 if (!getLangOpts().CPlusPlus2a)
12700 AllowRewrittenCandidates = false;
12702 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc);
12703 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op);
12705 // If either side is type-dependent, create an appropriate dependent
12707 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) {
12709 // If there are no functions to store, just build a dependent
12710 // BinaryOperator or CompoundAssignment.
12711 if (Opc <= BO_Assign || Opc > BO_OrAssign)
12712 return new (Context) BinaryOperator(
12713 Args[0], Args[1], Opc, Context.DependentTy, VK_RValue, OK_Ordinary,
12714 OpLoc, FPFeatures);
12716 return new (Context) CompoundAssignOperator(
12717 Args[0], Args[1], Opc, Context.DependentTy, VK_LValue, OK_Ordinary,
12718 Context.DependentTy, Context.DependentTy, OpLoc,
12722 // FIXME: save results of ADL from here?
12723 CXXRecordDecl *NamingClass = nullptr; // lookup ignores member operators
12724 // TODO: provide better source location info in DNLoc component.
12725 DeclarationNameInfo OpNameInfo(OpName, OpLoc);
12726 UnresolvedLookupExpr *Fn = UnresolvedLookupExpr::Create(
12727 Context, NamingClass, NestedNameSpecifierLoc(), OpNameInfo,
12728 /*ADL*/ PerformADL, IsOverloaded(Fns), Fns.begin(), Fns.end());
12729 return CXXOperatorCallExpr::Create(Context, Op, Fn, Args,
12730 Context.DependentTy, VK_RValue, OpLoc,
12734 // Always do placeholder-like conversions on the RHS.
12735 if (checkPlaceholderForOverload(*this, Args[1]))
12736 return ExprError();
12738 // Do placeholder-like conversion on the LHS; note that we should
12739 // not get here with a PseudoObject LHS.
12740 assert(Args[0]->getObjectKind() != OK_ObjCProperty);
12741 if (checkPlaceholderForOverload(*this, Args[0]))
12742 return ExprError();
12744 // If this is the assignment operator, we only perform overload resolution
12745 // if the left-hand side is a class or enumeration type. This is actually
12746 // a hack. The standard requires that we do overload resolution between the
12747 // various built-in candidates, but as DR507 points out, this can lead to
12748 // problems. So we do it this way, which pretty much follows what GCC does.
12749 // Note that we go the traditional code path for compound assignment forms.
12750 if (Opc == BO_Assign && !Args[0]->getType()->isOverloadableType())
12751 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]);
12753 // If this is the .* operator, which is not overloadable, just
12754 // create a built-in binary operator.
12755 if (Opc == BO_PtrMemD)
12756 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]);
12758 // Build an empty overload set.
12759 OverloadCandidateSet CandidateSet(
12760 OpLoc, OverloadCandidateSet::CSK_Operator,
12761 OverloadCandidateSet::OperatorRewriteInfo(Op, AllowRewrittenCandidates));
12763 OverloadedOperatorKind ExtraOp =
12764 AllowRewrittenCandidates ? getRewrittenOverloadedOperator(Op) : OO_None;
12766 // Add the candidates from the given function set. This also adds the
12767 // rewritten candidates using these functions if necessary.
12768 AddNonMemberOperatorCandidates(Fns, Args, CandidateSet);
12770 // Add operator candidates that are member functions.
12771 AddMemberOperatorCandidates(Op, OpLoc, Args, CandidateSet);
12772 if (CandidateSet.getRewriteInfo().shouldAddReversed(Op))
12773 AddMemberOperatorCandidates(Op, OpLoc, {Args[1], Args[0]}, CandidateSet,
12774 OverloadCandidateParamOrder::Reversed);
12776 // In C++20, also add any rewritten member candidates.
12778 AddMemberOperatorCandidates(ExtraOp, OpLoc, Args, CandidateSet);
12779 if (CandidateSet.getRewriteInfo().shouldAddReversed(ExtraOp))
12780 AddMemberOperatorCandidates(ExtraOp, OpLoc, {Args[1], Args[0]},
12782 OverloadCandidateParamOrder::Reversed);
12785 // Add candidates from ADL. Per [over.match.oper]p2, this lookup is not
12786 // performed for an assignment operator (nor for operator[] nor operator->,
12787 // which don't get here).
12788 if (Opc != BO_Assign && PerformADL) {
12789 AddArgumentDependentLookupCandidates(OpName, OpLoc, Args,
12790 /*ExplicitTemplateArgs*/ nullptr,
12793 DeclarationName ExtraOpName =
12794 Context.DeclarationNames.getCXXOperatorName(ExtraOp);
12795 AddArgumentDependentLookupCandidates(ExtraOpName, OpLoc, Args,
12796 /*ExplicitTemplateArgs*/ nullptr,
12801 // Add builtin operator candidates.
12803 // FIXME: We don't add any rewritten candidates here. This is strictly
12804 // incorrect; a builtin candidate could be hidden by a non-viable candidate,
12805 // resulting in our selecting a rewritten builtin candidate. For example:
12807 // enum class E { e };
12808 // bool operator!=(E, E) requires false;
12809 // bool k = E::e != E::e;
12811 // ... should select the rewritten builtin candidate 'operator==(E, E)'. But
12812 // it seems unreasonable to consider rewritten builtin candidates. A core
12813 // issue has been filed proposing to removed this requirement.
12814 AddBuiltinOperatorCandidates(Op, OpLoc, Args, CandidateSet);
12816 bool HadMultipleCandidates = (CandidateSet.size() > 1);
12818 // Perform overload resolution.
12819 OverloadCandidateSet::iterator Best;
12820 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) {
12822 // We found a built-in operator or an overloaded operator.
12823 FunctionDecl *FnDecl = Best->Function;
12825 bool IsReversed = (Best->RewriteKind & CRK_Reversed);
12827 std::swap(Args[0], Args[1]);
12830 Expr *Base = nullptr;
12831 // We matched an overloaded operator. Build a call to that
12834 OverloadedOperatorKind ChosenOp =
12835 FnDecl->getDeclName().getCXXOverloadedOperator();
12837 // C++2a [over.match.oper]p9:
12838 // If a rewritten operator== candidate is selected by overload
12839 // resolution for an operator@, its return type shall be cv bool
12840 if (Best->RewriteKind && ChosenOp == OO_EqualEqual &&
12841 !FnDecl->getReturnType()->isBooleanType()) {
12842 Diag(OpLoc, diag::err_ovl_rewrite_equalequal_not_bool)
12843 << FnDecl->getReturnType() << BinaryOperator::getOpcodeStr(Opc)
12844 << Args[0]->getSourceRange() << Args[1]->getSourceRange();
12845 Diag(FnDecl->getLocation(), diag::note_declared_at);
12846 return ExprError();
12849 if (AllowRewrittenCandidates && !IsReversed &&
12850 CandidateSet.getRewriteInfo().shouldAddReversed(ChosenOp)) {
12851 // We could have reversed this operator, but didn't. Check if the
12852 // reversed form was a viable candidate, and if so, if it had a
12853 // better conversion for either parameter. If so, this call is
12854 // formally ambiguous, and allowing it is an extension.
12855 for (OverloadCandidate &Cand : CandidateSet) {
12856 if (Cand.Viable && Cand.Function == FnDecl &&
12857 Cand.RewriteKind & CRK_Reversed) {
12858 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) {
12859 if (CompareImplicitConversionSequences(
12860 *this, OpLoc, Cand.Conversions[ArgIdx],
12861 Best->Conversions[ArgIdx]) ==
12862 ImplicitConversionSequence::Better) {
12863 Diag(OpLoc, diag::ext_ovl_ambiguous_oper_binary_reversed)
12864 << BinaryOperator::getOpcodeStr(Opc)
12865 << Args[0]->getType() << Args[1]->getType()
12866 << Args[0]->getSourceRange() << Args[1]->getSourceRange();
12867 Diag(FnDecl->getLocation(),
12868 diag::note_ovl_ambiguous_oper_binary_reversed_candidate);
12876 // Convert the arguments.
12877 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) {
12878 // Best->Access is only meaningful for class members.
12879 CheckMemberOperatorAccess(OpLoc, Args[0], Args[1], Best->FoundDecl);
12882 PerformCopyInitialization(
12883 InitializedEntity::InitializeParameter(Context,
12884 FnDecl->getParamDecl(0)),
12885 SourceLocation(), Args[1]);
12886 if (Arg1.isInvalid())
12887 return ExprError();
12890 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/nullptr,
12891 Best->FoundDecl, Method);
12892 if (Arg0.isInvalid())
12893 return ExprError();
12894 Base = Args[0] = Arg0.getAs<Expr>();
12895 Args[1] = RHS = Arg1.getAs<Expr>();
12897 // Convert the arguments.
12898 ExprResult Arg0 = PerformCopyInitialization(
12899 InitializedEntity::InitializeParameter(Context,
12900 FnDecl->getParamDecl(0)),
12901 SourceLocation(), Args[0]);
12902 if (Arg0.isInvalid())
12903 return ExprError();
12906 PerformCopyInitialization(
12907 InitializedEntity::InitializeParameter(Context,
12908 FnDecl->getParamDecl(1)),
12909 SourceLocation(), Args[1]);
12910 if (Arg1.isInvalid())
12911 return ExprError();
12912 Args[0] = LHS = Arg0.getAs<Expr>();
12913 Args[1] = RHS = Arg1.getAs<Expr>();
12916 // Build the actual expression node.
12917 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl,
12918 Best->FoundDecl, Base,
12919 HadMultipleCandidates, OpLoc);
12920 if (FnExpr.isInvalid())
12921 return ExprError();
12923 // Determine the result type.
12924 QualType ResultTy = FnDecl->getReturnType();
12925 ExprValueKind VK = Expr::getValueKindForType(ResultTy);
12926 ResultTy = ResultTy.getNonLValueExprType(Context);
12928 CXXOperatorCallExpr *TheCall = CXXOperatorCallExpr::Create(
12929 Context, ChosenOp, FnExpr.get(), Args, ResultTy, VK, OpLoc,
12930 FPFeatures, Best->IsADLCandidate);
12932 if (CheckCallReturnType(FnDecl->getReturnType(), OpLoc, TheCall,
12934 return ExprError();
12936 ArrayRef<const Expr *> ArgsArray(Args, 2);
12937 const Expr *ImplicitThis = nullptr;
12938 // Cut off the implicit 'this'.
12939 if (isa<CXXMethodDecl>(FnDecl)) {
12940 ImplicitThis = ArgsArray[0];
12941 ArgsArray = ArgsArray.slice(1);
12944 // Check for a self move.
12945 if (Op == OO_Equal)
12946 DiagnoseSelfMove(Args[0], Args[1], OpLoc);
12948 checkCall(FnDecl, nullptr, ImplicitThis, ArgsArray,
12949 isa<CXXMethodDecl>(FnDecl), OpLoc, TheCall->getSourceRange(),
12950 VariadicDoesNotApply);
12952 ExprResult R = MaybeBindToTemporary(TheCall);
12954 return ExprError();
12956 // For a rewritten candidate, we've already reversed the arguments
12957 // if needed. Perform the rest of the rewrite now.
12958 if ((Best->RewriteKind & CRK_DifferentOperator) ||
12959 (Op == OO_Spaceship && IsReversed)) {
12960 if (Op == OO_ExclaimEqual) {
12961 assert(ChosenOp == OO_EqualEqual && "unexpected operator name");
12962 R = CreateBuiltinUnaryOp(OpLoc, UO_LNot, R.get());
12964 assert(ChosenOp == OO_Spaceship && "unexpected operator name");
12965 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false);
12966 Expr *ZeroLiteral =
12967 IntegerLiteral::Create(Context, Zero, Context.IntTy, OpLoc);
12969 Sema::CodeSynthesisContext Ctx;
12970 Ctx.Kind = Sema::CodeSynthesisContext::RewritingOperatorAsSpaceship;
12971 Ctx.Entity = FnDecl;
12972 pushCodeSynthesisContext(Ctx);
12974 R = CreateOverloadedBinOp(
12975 OpLoc, Opc, Fns, IsReversed ? ZeroLiteral : R.get(),
12976 IsReversed ? R.get() : ZeroLiteral, PerformADL,
12977 /*AllowRewrittenCandidates=*/false);
12979 popCodeSynthesisContext();
12982 return ExprError();
12984 assert(ChosenOp == Op && "unexpected operator name");
12987 // Make a note in the AST if we did any rewriting.
12988 if (Best->RewriteKind != CRK_None)
12989 R = new (Context) CXXRewrittenBinaryOperator(R.get(), IsReversed);
12993 // We matched a built-in operator. Convert the arguments, then
12994 // break out so that we will build the appropriate built-in
12996 ExprResult ArgsRes0 = PerformImplicitConversion(
12997 Args[0], Best->BuiltinParamTypes[0], Best->Conversions[0],
12998 AA_Passing, CCK_ForBuiltinOverloadedOp);
12999 if (ArgsRes0.isInvalid())
13000 return ExprError();
13001 Args[0] = ArgsRes0.get();
13003 ExprResult ArgsRes1 = PerformImplicitConversion(
13004 Args[1], Best->BuiltinParamTypes[1], Best->Conversions[1],
13005 AA_Passing, CCK_ForBuiltinOverloadedOp);
13006 if (ArgsRes1.isInvalid())
13007 return ExprError();
13008 Args[1] = ArgsRes1.get();
13013 case OR_No_Viable_Function: {
13014 // C++ [over.match.oper]p9:
13015 // If the operator is the operator , [...] and there are no
13016 // viable functions, then the operator is assumed to be the
13017 // built-in operator and interpreted according to clause 5.
13018 if (Opc == BO_Comma)
13021 // For class as left operand for assignment or compound assignment
13022 // operator do not fall through to handling in built-in, but report that
13023 // no overloaded assignment operator found
13024 ExprResult Result = ExprError();
13025 StringRef OpcStr = BinaryOperator::getOpcodeStr(Opc);
13026 auto Cands = CandidateSet.CompleteCandidates(*this, OCD_AllCandidates,
13028 if (Args[0]->getType()->isRecordType() &&
13029 Opc >= BO_Assign && Opc <= BO_OrAssign) {
13030 Diag(OpLoc, diag::err_ovl_no_viable_oper)
13031 << BinaryOperator::getOpcodeStr(Opc)
13032 << Args[0]->getSourceRange() << Args[1]->getSourceRange();
13033 if (Args[0]->getType()->isIncompleteType()) {
13034 Diag(OpLoc, diag::note_assign_lhs_incomplete)
13035 << Args[0]->getType()
13036 << Args[0]->getSourceRange() << Args[1]->getSourceRange();
13039 // This is an erroneous use of an operator which can be overloaded by
13040 // a non-member function. Check for non-member operators which were
13041 // defined too late to be candidates.
13042 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args))
13043 // FIXME: Recover by calling the found function.
13044 return ExprError();
13046 // No viable function; try to create a built-in operation, which will
13047 // produce an error. Then, show the non-viable candidates.
13048 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]);
13050 assert(Result.isInvalid() &&
13051 "C++ binary operator overloading is missing candidates!");
13052 CandidateSet.NoteCandidates(*this, Args, Cands, OpcStr, OpLoc);
13057 CandidateSet.NoteCandidates(
13058 PartialDiagnosticAt(OpLoc, PDiag(diag::err_ovl_ambiguous_oper_binary)
13059 << BinaryOperator::getOpcodeStr(Opc)
13060 << Args[0]->getType()
13061 << Args[1]->getType()
13062 << Args[0]->getSourceRange()
13063 << Args[1]->getSourceRange()),
13064 *this, OCD_ViableCandidates, Args, BinaryOperator::getOpcodeStr(Opc),
13066 return ExprError();
13069 if (isImplicitlyDeleted(Best->Function)) {
13070 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function);
13071 Diag(OpLoc, diag::err_ovl_deleted_special_oper)
13072 << Context.getRecordType(Method->getParent())
13073 << getSpecialMember(Method);
13075 // The user probably meant to call this special member. Just
13076 // explain why it's deleted.
13077 NoteDeletedFunction(Method);
13078 return ExprError();
13080 CandidateSet.NoteCandidates(
13081 PartialDiagnosticAt(
13082 OpLoc, PDiag(diag::err_ovl_deleted_oper)
13083 << getOperatorSpelling(Best->Function->getDeclName()
13084 .getCXXOverloadedOperator())
13085 << Args[0]->getSourceRange()
13086 << Args[1]->getSourceRange()),
13087 *this, OCD_AllCandidates, Args, BinaryOperator::getOpcodeStr(Opc),
13089 return ExprError();
13092 // We matched a built-in operator; build it.
13093 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]);
13097 Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc,
13098 SourceLocation RLoc,
13099 Expr *Base, Expr *Idx) {
13100 Expr *Args[2] = { Base, Idx };
13101 DeclarationName OpName =
13102 Context.DeclarationNames.getCXXOperatorName(OO_Subscript);
13104 // If either side is type-dependent, create an appropriate dependent
13106 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) {
13108 CXXRecordDecl *NamingClass = nullptr; // lookup ignores member operators
13109 // CHECKME: no 'operator' keyword?
13110 DeclarationNameInfo OpNameInfo(OpName, LLoc);
13111 OpNameInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc));
13112 UnresolvedLookupExpr *Fn
13113 = UnresolvedLookupExpr::Create(Context, NamingClass,
13114 NestedNameSpecifierLoc(), OpNameInfo,
13115 /*ADL*/ true, /*Overloaded*/ false,
13116 UnresolvedSetIterator(),
13117 UnresolvedSetIterator());
13118 // Can't add any actual overloads yet
13120 return CXXOperatorCallExpr::Create(Context, OO_Subscript, Fn, Args,
13121 Context.DependentTy, VK_RValue, RLoc,
13125 // Handle placeholders on both operands.
13126 if (checkPlaceholderForOverload(*this, Args[0]))
13127 return ExprError();
13128 if (checkPlaceholderForOverload(*this, Args[1]))
13129 return ExprError();
13131 // Build an empty overload set.
13132 OverloadCandidateSet CandidateSet(LLoc, OverloadCandidateSet::CSK_Operator);
13134 // Subscript can only be overloaded as a member function.
13136 // Add operator candidates that are member functions.
13137 AddMemberOperatorCandidates(OO_Subscript, LLoc, Args, CandidateSet);
13139 // Add builtin operator candidates.
13140 AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, CandidateSet);
13142 bool HadMultipleCandidates = (CandidateSet.size() > 1);
13144 // Perform overload resolution.
13145 OverloadCandidateSet::iterator Best;
13146 switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) {
13148 // We found a built-in operator or an overloaded operator.
13149 FunctionDecl *FnDecl = Best->Function;
13152 // We matched an overloaded operator. Build a call to that
13155 CheckMemberOperatorAccess(LLoc, Args[0], Args[1], Best->FoundDecl);
13157 // Convert the arguments.
13158 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl);
13160 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/nullptr,
13161 Best->FoundDecl, Method);
13162 if (Arg0.isInvalid())
13163 return ExprError();
13164 Args[0] = Arg0.get();
13166 // Convert the arguments.
13167 ExprResult InputInit
13168 = PerformCopyInitialization(InitializedEntity::InitializeParameter(
13170 FnDecl->getParamDecl(0)),
13173 if (InputInit.isInvalid())
13174 return ExprError();
13176 Args[1] = InputInit.getAs<Expr>();
13178 // Build the actual expression node.
13179 DeclarationNameInfo OpLocInfo(OpName, LLoc);
13180 OpLocInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc));
13181 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl,
13184 HadMultipleCandidates,
13185 OpLocInfo.getLoc(),
13186 OpLocInfo.getInfo());
13187 if (FnExpr.isInvalid())
13188 return ExprError();
13190 // Determine the result type
13191 QualType ResultTy = FnDecl->getReturnType();
13192 ExprValueKind VK = Expr::getValueKindForType(ResultTy);
13193 ResultTy = ResultTy.getNonLValueExprType(Context);
13195 CXXOperatorCallExpr *TheCall =
13196 CXXOperatorCallExpr::Create(Context, OO_Subscript, FnExpr.get(),
13197 Args, ResultTy, VK, RLoc, FPOptions());
13199 if (CheckCallReturnType(FnDecl->getReturnType(), LLoc, TheCall, FnDecl))
13200 return ExprError();
13202 if (CheckFunctionCall(Method, TheCall,
13203 Method->getType()->castAs<FunctionProtoType>()))
13204 return ExprError();
13206 return MaybeBindToTemporary(TheCall);
13208 // We matched a built-in operator. Convert the arguments, then
13209 // break out so that we will build the appropriate built-in
13211 ExprResult ArgsRes0 = PerformImplicitConversion(
13212 Args[0], Best->BuiltinParamTypes[0], Best->Conversions[0],
13213 AA_Passing, CCK_ForBuiltinOverloadedOp);
13214 if (ArgsRes0.isInvalid())
13215 return ExprError();
13216 Args[0] = ArgsRes0.get();
13218 ExprResult ArgsRes1 = PerformImplicitConversion(
13219 Args[1], Best->BuiltinParamTypes[1], Best->Conversions[1],
13220 AA_Passing, CCK_ForBuiltinOverloadedOp);
13221 if (ArgsRes1.isInvalid())
13222 return ExprError();
13223 Args[1] = ArgsRes1.get();
13229 case OR_No_Viable_Function: {
13230 PartialDiagnostic PD = CandidateSet.empty()
13231 ? (PDiag(diag::err_ovl_no_oper)
13232 << Args[0]->getType() << /*subscript*/ 0
13233 << Args[0]->getSourceRange() << Args[1]->getSourceRange())
13234 : (PDiag(diag::err_ovl_no_viable_subscript)
13235 << Args[0]->getType() << Args[0]->getSourceRange()
13236 << Args[1]->getSourceRange());
13237 CandidateSet.NoteCandidates(PartialDiagnosticAt(LLoc, PD), *this,
13238 OCD_AllCandidates, Args, "[]", LLoc);
13239 return ExprError();
13243 CandidateSet.NoteCandidates(
13244 PartialDiagnosticAt(LLoc, PDiag(diag::err_ovl_ambiguous_oper_binary)
13245 << "[]" << Args[0]->getType()
13246 << Args[1]->getType()
13247 << Args[0]->getSourceRange()
13248 << Args[1]->getSourceRange()),
13249 *this, OCD_ViableCandidates, Args, "[]", LLoc);
13250 return ExprError();
13253 CandidateSet.NoteCandidates(
13254 PartialDiagnosticAt(LLoc, PDiag(diag::err_ovl_deleted_oper)
13255 << "[]" << Args[0]->getSourceRange()
13256 << Args[1]->getSourceRange()),
13257 *this, OCD_AllCandidates, Args, "[]", LLoc);
13258 return ExprError();
13261 // We matched a built-in operator; build it.
13262 return CreateBuiltinArraySubscriptExpr(Args[0], LLoc, Args[1], RLoc);
13265 /// BuildCallToMemberFunction - Build a call to a member
13266 /// function. MemExpr is the expression that refers to the member
13267 /// function (and includes the object parameter), Args/NumArgs are the
13268 /// arguments to the function call (not including the object
13269 /// parameter). The caller needs to validate that the member
13270 /// expression refers to a non-static member function or an overloaded
13271 /// member function.
13273 Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE,
13274 SourceLocation LParenLoc,
13276 SourceLocation RParenLoc) {
13277 assert(MemExprE->getType() == Context.BoundMemberTy ||
13278 MemExprE->getType() == Context.OverloadTy);
13280 // Dig out the member expression. This holds both the object
13281 // argument and the member function we're referring to.
13282 Expr *NakedMemExpr = MemExprE->IgnoreParens();
13284 // Determine whether this is a call to a pointer-to-member function.
13285 if (BinaryOperator *op = dyn_cast<BinaryOperator>(NakedMemExpr)) {
13286 assert(op->getType() == Context.BoundMemberTy);
13287 assert(op->getOpcode() == BO_PtrMemD || op->getOpcode() == BO_PtrMemI);
13290 op->getRHS()->getType()->castAs<MemberPointerType>()->getPointeeType();
13292 const FunctionProtoType *proto = fnType->castAs<FunctionProtoType>();
13293 QualType resultType = proto->getCallResultType(Context);
13294 ExprValueKind valueKind = Expr::getValueKindForType(proto->getReturnType());
13296 // Check that the object type isn't more qualified than the
13297 // member function we're calling.
13298 Qualifiers funcQuals = proto->getMethodQuals();
13300 QualType objectType = op->getLHS()->getType();
13301 if (op->getOpcode() == BO_PtrMemI)
13302 objectType = objectType->castAs<PointerType>()->getPointeeType();
13303 Qualifiers objectQuals = objectType.getQualifiers();
13305 Qualifiers difference = objectQuals - funcQuals;
13306 difference.removeObjCGCAttr();
13307 difference.removeAddressSpace();
13309 std::string qualsString = difference.getAsString();
13310 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals)
13311 << fnType.getUnqualifiedType()
13313 << (qualsString.find(' ') == std::string::npos ? 1 : 2);
13316 CXXMemberCallExpr *call =
13317 CXXMemberCallExpr::Create(Context, MemExprE, Args, resultType,
13318 valueKind, RParenLoc, proto->getNumParams());
13320 if (CheckCallReturnType(proto->getReturnType(), op->getRHS()->getBeginLoc(),
13322 return ExprError();
13324 if (ConvertArgumentsForCall(call, op, nullptr, proto, Args, RParenLoc))
13325 return ExprError();
13327 if (CheckOtherCall(call, proto))
13328 return ExprError();
13330 return MaybeBindToTemporary(call);
13333 if (isa<CXXPseudoDestructorExpr>(NakedMemExpr))
13334 return CallExpr::Create(Context, MemExprE, Args, Context.VoidTy, VK_RValue,
13337 UnbridgedCastsSet UnbridgedCasts;
13338 if (checkArgPlaceholdersForOverload(*this, Args, UnbridgedCasts))
13339 return ExprError();
13341 MemberExpr *MemExpr;
13342 CXXMethodDecl *Method = nullptr;
13343 DeclAccessPair FoundDecl = DeclAccessPair::make(nullptr, AS_public);
13344 NestedNameSpecifier *Qualifier = nullptr;
13345 if (isa<MemberExpr>(NakedMemExpr)) {
13346 MemExpr = cast<MemberExpr>(NakedMemExpr);
13347 Method = cast<CXXMethodDecl>(MemExpr->getMemberDecl());
13348 FoundDecl = MemExpr->getFoundDecl();
13349 Qualifier = MemExpr->getQualifier();
13350 UnbridgedCasts.restore();
13352 UnresolvedMemberExpr *UnresExpr = cast<UnresolvedMemberExpr>(NakedMemExpr);
13353 Qualifier = UnresExpr->getQualifier();
13355 QualType ObjectType = UnresExpr->getBaseType();
13356 Expr::Classification ObjectClassification
13357 = UnresExpr->isArrow()? Expr::Classification::makeSimpleLValue()
13358 : UnresExpr->getBase()->Classify(Context);
13360 // Add overload candidates
13361 OverloadCandidateSet CandidateSet(UnresExpr->getMemberLoc(),
13362 OverloadCandidateSet::CSK_Normal);
13364 // FIXME: avoid copy.
13365 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = nullptr;
13366 if (UnresExpr->hasExplicitTemplateArgs()) {
13367 UnresExpr->copyTemplateArgumentsInto(TemplateArgsBuffer);
13368 TemplateArgs = &TemplateArgsBuffer;
13371 for (UnresolvedMemberExpr::decls_iterator I = UnresExpr->decls_begin(),
13372 E = UnresExpr->decls_end(); I != E; ++I) {
13374 NamedDecl *Func = *I;
13375 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(Func->getDeclContext());
13376 if (isa<UsingShadowDecl>(Func))
13377 Func = cast<UsingShadowDecl>(Func)->getTargetDecl();
13380 // Microsoft supports direct constructor calls.
13381 if (getLangOpts().MicrosoftExt && isa<CXXConstructorDecl>(Func)) {
13382 AddOverloadCandidate(cast<CXXConstructorDecl>(Func), I.getPair(), Args,
13384 /*SuppressUserConversions*/ false);
13385 } else if ((Method = dyn_cast<CXXMethodDecl>(Func))) {
13386 // If explicit template arguments were provided, we can't call a
13387 // non-template member function.
13391 AddMethodCandidate(Method, I.getPair(), ActingDC, ObjectType,
13392 ObjectClassification, Args, CandidateSet,
13393 /*SuppressUserConversions=*/false);
13395 AddMethodTemplateCandidate(
13396 cast<FunctionTemplateDecl>(Func), I.getPair(), ActingDC,
13397 TemplateArgs, ObjectType, ObjectClassification, Args, CandidateSet,
13398 /*SuppressUserConversions=*/false);
13402 DeclarationName DeclName = UnresExpr->getMemberName();
13404 UnbridgedCasts.restore();
13406 OverloadCandidateSet::iterator Best;
13407 switch (CandidateSet.BestViableFunction(*this, UnresExpr->getBeginLoc(),
13410 Method = cast<CXXMethodDecl>(Best->Function);
13411 FoundDecl = Best->FoundDecl;
13412 CheckUnresolvedMemberAccess(UnresExpr, Best->FoundDecl);
13413 if (DiagnoseUseOfDecl(Best->FoundDecl, UnresExpr->getNameLoc()))
13414 return ExprError();
13415 // If FoundDecl is different from Method (such as if one is a template
13416 // and the other a specialization), make sure DiagnoseUseOfDecl is
13418 // FIXME: This would be more comprehensively addressed by modifying
13419 // DiagnoseUseOfDecl to accept both the FoundDecl and the decl
13421 if (Method != FoundDecl.getDecl() &&
13422 DiagnoseUseOfDecl(Method, UnresExpr->getNameLoc()))
13423 return ExprError();
13426 case OR_No_Viable_Function:
13427 CandidateSet.NoteCandidates(
13428 PartialDiagnosticAt(
13429 UnresExpr->getMemberLoc(),
13430 PDiag(diag::err_ovl_no_viable_member_function_in_call)
13431 << DeclName << MemExprE->getSourceRange()),
13432 *this, OCD_AllCandidates, Args);
13433 // FIXME: Leaking incoming expressions!
13434 return ExprError();
13437 CandidateSet.NoteCandidates(
13438 PartialDiagnosticAt(UnresExpr->getMemberLoc(),
13439 PDiag(diag::err_ovl_ambiguous_member_call)
13440 << DeclName << MemExprE->getSourceRange()),
13441 *this, OCD_AllCandidates, Args);
13442 // FIXME: Leaking incoming expressions!
13443 return ExprError();
13446 CandidateSet.NoteCandidates(
13447 PartialDiagnosticAt(UnresExpr->getMemberLoc(),
13448 PDiag(diag::err_ovl_deleted_member_call)
13449 << DeclName << MemExprE->getSourceRange()),
13450 *this, OCD_AllCandidates, Args);
13451 // FIXME: Leaking incoming expressions!
13452 return ExprError();
13455 MemExprE = FixOverloadedFunctionReference(MemExprE, FoundDecl, Method);
13457 // If overload resolution picked a static member, build a
13458 // non-member call based on that function.
13459 if (Method->isStatic()) {
13460 return BuildResolvedCallExpr(MemExprE, Method, LParenLoc, Args,
13464 MemExpr = cast<MemberExpr>(MemExprE->IgnoreParens());
13467 QualType ResultType = Method->getReturnType();
13468 ExprValueKind VK = Expr::getValueKindForType(ResultType);
13469 ResultType = ResultType.getNonLValueExprType(Context);
13471 assert(Method && "Member call to something that isn't a method?");
13472 const auto *Proto = Method->getType()->getAs<FunctionProtoType>();
13473 CXXMemberCallExpr *TheCall =
13474 CXXMemberCallExpr::Create(Context, MemExprE, Args, ResultType, VK,
13475 RParenLoc, Proto->getNumParams());
13477 // Check for a valid return type.
13478 if (CheckCallReturnType(Method->getReturnType(), MemExpr->getMemberLoc(),
13480 return ExprError();
13482 // Convert the object argument (for a non-static member function call).
13483 // We only need to do this if there was actually an overload; otherwise
13484 // it was done at lookup.
13485 if (!Method->isStatic()) {
13486 ExprResult ObjectArg =
13487 PerformObjectArgumentInitialization(MemExpr->getBase(), Qualifier,
13488 FoundDecl, Method);
13489 if (ObjectArg.isInvalid())
13490 return ExprError();
13491 MemExpr->setBase(ObjectArg.get());
13494 // Convert the rest of the arguments
13495 if (ConvertArgumentsForCall(TheCall, MemExpr, Method, Proto, Args,
13497 return ExprError();
13499 DiagnoseSentinelCalls(Method, LParenLoc, Args);
13501 if (CheckFunctionCall(Method, TheCall, Proto))
13502 return ExprError();
13504 // In the case the method to call was not selected by the overloading
13505 // resolution process, we still need to handle the enable_if attribute. Do
13506 // that here, so it will not hide previous -- and more relevant -- errors.
13507 if (auto *MemE = dyn_cast<MemberExpr>(NakedMemExpr)) {
13508 if (const EnableIfAttr *Attr = CheckEnableIf(Method, Args, true)) {
13509 Diag(MemE->getMemberLoc(),
13510 diag::err_ovl_no_viable_member_function_in_call)
13511 << Method << Method->getSourceRange();
13512 Diag(Method->getLocation(),
13513 diag::note_ovl_candidate_disabled_by_function_cond_attr)
13514 << Attr->getCond()->getSourceRange() << Attr->getMessage();
13515 return ExprError();
13519 if ((isa<CXXConstructorDecl>(CurContext) ||
13520 isa<CXXDestructorDecl>(CurContext)) &&
13521 TheCall->getMethodDecl()->isPure()) {
13522 const CXXMethodDecl *MD = TheCall->getMethodDecl();
13524 if (isa<CXXThisExpr>(MemExpr->getBase()->IgnoreParenCasts()) &&
13525 MemExpr->performsVirtualDispatch(getLangOpts())) {
13526 Diag(MemExpr->getBeginLoc(),
13527 diag::warn_call_to_pure_virtual_member_function_from_ctor_dtor)
13528 << MD->getDeclName() << isa<CXXDestructorDecl>(CurContext)
13529 << MD->getParent()->getDeclName();
13531 Diag(MD->getBeginLoc(), diag::note_previous_decl) << MD->getDeclName();
13532 if (getLangOpts().AppleKext)
13533 Diag(MemExpr->getBeginLoc(), diag::note_pure_qualified_call_kext)
13534 << MD->getParent()->getDeclName() << MD->getDeclName();
13538 if (CXXDestructorDecl *DD =
13539 dyn_cast<CXXDestructorDecl>(TheCall->getMethodDecl())) {
13540 // a->A::f() doesn't go through the vtable, except in AppleKext mode.
13541 bool CallCanBeVirtual = !MemExpr->hasQualifier() || getLangOpts().AppleKext;
13542 CheckVirtualDtorCall(DD, MemExpr->getBeginLoc(), /*IsDelete=*/false,
13543 CallCanBeVirtual, /*WarnOnNonAbstractTypes=*/true,
13544 MemExpr->getMemberLoc());
13547 return MaybeBindToTemporary(TheCall);
13550 /// BuildCallToObjectOfClassType - Build a call to an object of class
13551 /// type (C++ [over.call.object]), which can end up invoking an
13552 /// overloaded function call operator (@c operator()) or performing a
13553 /// user-defined conversion on the object argument.
13555 Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj,
13556 SourceLocation LParenLoc,
13558 SourceLocation RParenLoc) {
13559 if (checkPlaceholderForOverload(*this, Obj))
13560 return ExprError();
13561 ExprResult Object = Obj;
13563 UnbridgedCastsSet UnbridgedCasts;
13564 if (checkArgPlaceholdersForOverload(*this, Args, UnbridgedCasts))
13565 return ExprError();
13567 assert(Object.get()->getType()->isRecordType() &&
13568 "Requires object type argument");
13569 const RecordType *Record = Object.get()->getType()->getAs<RecordType>();
13571 // C++ [over.call.object]p1:
13572 // If the primary-expression E in the function call syntax
13573 // evaluates to a class object of type "cv T", then the set of
13574 // candidate functions includes at least the function call
13575 // operators of T. The function call operators of T are obtained by
13576 // ordinary lookup of the name operator() in the context of
13578 OverloadCandidateSet CandidateSet(LParenLoc,
13579 OverloadCandidateSet::CSK_Operator);
13580 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call);
13582 if (RequireCompleteType(LParenLoc, Object.get()->getType(),
13583 diag::err_incomplete_object_call, Object.get()))
13586 LookupResult R(*this, OpName, LParenLoc, LookupOrdinaryName);
13587 LookupQualifiedName(R, Record->getDecl());
13588 R.suppressDiagnostics();
13590 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end();
13591 Oper != OperEnd; ++Oper) {
13592 AddMethodCandidate(Oper.getPair(), Object.get()->getType(),
13593 Object.get()->Classify(Context), Args, CandidateSet,
13594 /*SuppressUserConversion=*/false);
13597 // C++ [over.call.object]p2:
13598 // In addition, for each (non-explicit in C++0x) conversion function
13599 // declared in T of the form
13601 // operator conversion-type-id () cv-qualifier;
13603 // where cv-qualifier is the same cv-qualification as, or a
13604 // greater cv-qualification than, cv, and where conversion-type-id
13605 // denotes the type "pointer to function of (P1,...,Pn) returning
13606 // R", or the type "reference to pointer to function of
13607 // (P1,...,Pn) returning R", or the type "reference to function
13608 // of (P1,...,Pn) returning R", a surrogate call function [...]
13609 // is also considered as a candidate function. Similarly,
13610 // surrogate call functions are added to the set of candidate
13611 // functions for each conversion function declared in an
13612 // accessible base class provided the function is not hidden
13613 // within T by another intervening declaration.
13614 const auto &Conversions =
13615 cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions();
13616 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
13618 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext());
13619 if (isa<UsingShadowDecl>(D))
13620 D = cast<UsingShadowDecl>(D)->getTargetDecl();
13622 // Skip over templated conversion functions; they aren't
13624 if (isa<FunctionTemplateDecl>(D))
13627 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D);
13628 if (!Conv->isExplicit()) {
13629 // Strip the reference type (if any) and then the pointer type (if
13630 // any) to get down to what might be a function type.
13631 QualType ConvType = Conv->getConversionType().getNonReferenceType();
13632 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
13633 ConvType = ConvPtrType->getPointeeType();
13635 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>())
13637 AddSurrogateCandidate(Conv, I.getPair(), ActingContext, Proto,
13638 Object.get(), Args, CandidateSet);
13643 bool HadMultipleCandidates = (CandidateSet.size() > 1);
13645 // Perform overload resolution.
13646 OverloadCandidateSet::iterator Best;
13647 switch (CandidateSet.BestViableFunction(*this, Object.get()->getBeginLoc(),
13650 // Overload resolution succeeded; we'll build the appropriate call
13654 case OR_No_Viable_Function: {
13655 PartialDiagnostic PD =
13656 CandidateSet.empty()
13657 ? (PDiag(diag::err_ovl_no_oper)
13658 << Object.get()->getType() << /*call*/ 1
13659 << Object.get()->getSourceRange())
13660 : (PDiag(diag::err_ovl_no_viable_object_call)
13661 << Object.get()->getType() << Object.get()->getSourceRange());
13662 CandidateSet.NoteCandidates(
13663 PartialDiagnosticAt(Object.get()->getBeginLoc(), PD), *this,
13664 OCD_AllCandidates, Args);
13668 CandidateSet.NoteCandidates(
13669 PartialDiagnosticAt(Object.get()->getBeginLoc(),
13670 PDiag(diag::err_ovl_ambiguous_object_call)
13671 << Object.get()->getType()
13672 << Object.get()->getSourceRange()),
13673 *this, OCD_ViableCandidates, Args);
13677 CandidateSet.NoteCandidates(
13678 PartialDiagnosticAt(Object.get()->getBeginLoc(),
13679 PDiag(diag::err_ovl_deleted_object_call)
13680 << Object.get()->getType()
13681 << Object.get()->getSourceRange()),
13682 *this, OCD_AllCandidates, Args);
13686 if (Best == CandidateSet.end())
13689 UnbridgedCasts.restore();
13691 if (Best->Function == nullptr) {
13692 // Since there is no function declaration, this is one of the
13693 // surrogate candidates. Dig out the conversion function.
13694 CXXConversionDecl *Conv
13695 = cast<CXXConversionDecl>(
13696 Best->Conversions[0].UserDefined.ConversionFunction);
13698 CheckMemberOperatorAccess(LParenLoc, Object.get(), nullptr,
13700 if (DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc))
13701 return ExprError();
13702 assert(Conv == Best->FoundDecl.getDecl() &&
13703 "Found Decl & conversion-to-functionptr should be same, right?!");
13704 // We selected one of the surrogate functions that converts the
13705 // object parameter to a function pointer. Perform the conversion
13706 // on the object argument, then let BuildCallExpr finish the job.
13708 // Create an implicit member expr to refer to the conversion operator.
13709 // and then call it.
13710 ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl,
13711 Conv, HadMultipleCandidates);
13712 if (Call.isInvalid())
13713 return ExprError();
13714 // Record usage of conversion in an implicit cast.
13715 Call = ImplicitCastExpr::Create(Context, Call.get()->getType(),
13716 CK_UserDefinedConversion, Call.get(),
13717 nullptr, VK_RValue);
13719 return BuildCallExpr(S, Call.get(), LParenLoc, Args, RParenLoc);
13722 CheckMemberOperatorAccess(LParenLoc, Object.get(), nullptr, Best->FoundDecl);
13724 // We found an overloaded operator(). Build a CXXOperatorCallExpr
13725 // that calls this method, using Object for the implicit object
13726 // parameter and passing along the remaining arguments.
13727 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function);
13729 // An error diagnostic has already been printed when parsing the declaration.
13730 if (Method->isInvalidDecl())
13731 return ExprError();
13733 const FunctionProtoType *Proto =
13734 Method->getType()->getAs<FunctionProtoType>();
13736 unsigned NumParams = Proto->getNumParams();
13738 DeclarationNameInfo OpLocInfo(
13739 Context.DeclarationNames.getCXXOperatorName(OO_Call), LParenLoc);
13740 OpLocInfo.setCXXOperatorNameRange(SourceRange(LParenLoc, RParenLoc));
13741 ExprResult NewFn = CreateFunctionRefExpr(*this, Method, Best->FoundDecl,
13742 Obj, HadMultipleCandidates,
13743 OpLocInfo.getLoc(),
13744 OpLocInfo.getInfo());
13745 if (NewFn.isInvalid())
13748 // The number of argument slots to allocate in the call. If we have default
13749 // arguments we need to allocate space for them as well. We additionally
13750 // need one more slot for the object parameter.
13751 unsigned NumArgsSlots = 1 + std::max<unsigned>(Args.size(), NumParams);
13753 // Build the full argument list for the method call (the implicit object
13754 // parameter is placed at the beginning of the list).
13755 SmallVector<Expr *, 8> MethodArgs(NumArgsSlots);
13757 bool IsError = false;
13759 // Initialize the implicit object parameter.
13760 ExprResult ObjRes =
13761 PerformObjectArgumentInitialization(Object.get(), /*Qualifier=*/nullptr,
13762 Best->FoundDecl, Method);
13763 if (ObjRes.isInvalid())
13767 MethodArgs[0] = Object.get();
13769 // Check the argument types.
13770 for (unsigned i = 0; i != NumParams; i++) {
13772 if (i < Args.size()) {
13775 // Pass the argument.
13777 ExprResult InputInit
13778 = PerformCopyInitialization(InitializedEntity::InitializeParameter(
13780 Method->getParamDecl(i)),
13781 SourceLocation(), Arg);
13783 IsError |= InputInit.isInvalid();
13784 Arg = InputInit.getAs<Expr>();
13787 = BuildCXXDefaultArgExpr(LParenLoc, Method, Method->getParamDecl(i));
13788 if (DefArg.isInvalid()) {
13793 Arg = DefArg.getAs<Expr>();
13796 MethodArgs[i + 1] = Arg;
13799 // If this is a variadic call, handle args passed through "...".
13800 if (Proto->isVariadic()) {
13801 // Promote the arguments (C99 6.5.2.2p7).
13802 for (unsigned i = NumParams, e = Args.size(); i < e; i++) {
13803 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod,
13805 IsError |= Arg.isInvalid();
13806 MethodArgs[i + 1] = Arg.get();
13813 DiagnoseSentinelCalls(Method, LParenLoc, Args);
13815 // Once we've built TheCall, all of the expressions are properly owned.
13816 QualType ResultTy = Method->getReturnType();
13817 ExprValueKind VK = Expr::getValueKindForType(ResultTy);
13818 ResultTy = ResultTy.getNonLValueExprType(Context);
13820 CXXOperatorCallExpr *TheCall =
13821 CXXOperatorCallExpr::Create(Context, OO_Call, NewFn.get(), MethodArgs,
13822 ResultTy, VK, RParenLoc, FPOptions());
13824 if (CheckCallReturnType(Method->getReturnType(), LParenLoc, TheCall, Method))
13827 if (CheckFunctionCall(Method, TheCall, Proto))
13830 return MaybeBindToTemporary(TheCall);
13833 /// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator->
13834 /// (if one exists), where @c Base is an expression of class type and
13835 /// @c Member is the name of the member we're trying to find.
13837 Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc,
13838 bool *NoArrowOperatorFound) {
13839 assert(Base->getType()->isRecordType() &&
13840 "left-hand side must have class type");
13842 if (checkPlaceholderForOverload(*this, Base))
13843 return ExprError();
13845 SourceLocation Loc = Base->getExprLoc();
13847 // C++ [over.ref]p1:
13849 // [...] An expression x->m is interpreted as (x.operator->())->m
13850 // for a class object x of type T if T::operator->() exists and if
13851 // the operator is selected as the best match function by the
13852 // overload resolution mechanism (13.3).
13853 DeclarationName OpName =
13854 Context.DeclarationNames.getCXXOperatorName(OO_Arrow);
13855 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Operator);
13856 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>();
13858 if (RequireCompleteType(Loc, Base->getType(),
13859 diag::err_typecheck_incomplete_tag, Base))
13860 return ExprError();
13862 LookupResult R(*this, OpName, OpLoc, LookupOrdinaryName);
13863 LookupQualifiedName(R, BaseRecord->getDecl());
13864 R.suppressDiagnostics();
13866 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end();
13867 Oper != OperEnd; ++Oper) {
13868 AddMethodCandidate(Oper.getPair(), Base->getType(), Base->Classify(Context),
13869 None, CandidateSet, /*SuppressUserConversion=*/false);
13872 bool HadMultipleCandidates = (CandidateSet.size() > 1);
13874 // Perform overload resolution.
13875 OverloadCandidateSet::iterator Best;
13876 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) {
13878 // Overload resolution succeeded; we'll build the call below.
13881 case OR_No_Viable_Function: {
13882 auto Cands = CandidateSet.CompleteCandidates(*this, OCD_AllCandidates, Base);
13883 if (CandidateSet.empty()) {
13884 QualType BaseType = Base->getType();
13885 if (NoArrowOperatorFound) {
13886 // Report this specific error to the caller instead of emitting a
13887 // diagnostic, as requested.
13888 *NoArrowOperatorFound = true;
13889 return ExprError();
13891 Diag(OpLoc, diag::err_typecheck_member_reference_arrow)
13892 << BaseType << Base->getSourceRange();
13893 if (BaseType->isRecordType() && !BaseType->isPointerType()) {
13894 Diag(OpLoc, diag::note_typecheck_member_reference_suggestion)
13895 << FixItHint::CreateReplacement(OpLoc, ".");
13898 Diag(OpLoc, diag::err_ovl_no_viable_oper)
13899 << "operator->" << Base->getSourceRange();
13900 CandidateSet.NoteCandidates(*this, Base, Cands);
13901 return ExprError();
13904 CandidateSet.NoteCandidates(
13905 PartialDiagnosticAt(OpLoc, PDiag(diag::err_ovl_ambiguous_oper_unary)
13906 << "->" << Base->getType()
13907 << Base->getSourceRange()),
13908 *this, OCD_ViableCandidates, Base);
13909 return ExprError();
13912 CandidateSet.NoteCandidates(
13913 PartialDiagnosticAt(OpLoc, PDiag(diag::err_ovl_deleted_oper)
13914 << "->" << Base->getSourceRange()),
13915 *this, OCD_AllCandidates, Base);
13916 return ExprError();
13919 CheckMemberOperatorAccess(OpLoc, Base, nullptr, Best->FoundDecl);
13921 // Convert the object parameter.
13922 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function);
13923 ExprResult BaseResult =
13924 PerformObjectArgumentInitialization(Base, /*Qualifier=*/nullptr,
13925 Best->FoundDecl, Method);
13926 if (BaseResult.isInvalid())
13927 return ExprError();
13928 Base = BaseResult.get();
13930 // Build the operator call.
13931 ExprResult FnExpr = CreateFunctionRefExpr(*this, Method, Best->FoundDecl,
13932 Base, HadMultipleCandidates, OpLoc);
13933 if (FnExpr.isInvalid())
13934 return ExprError();
13936 QualType ResultTy = Method->getReturnType();
13937 ExprValueKind VK = Expr::getValueKindForType(ResultTy);
13938 ResultTy = ResultTy.getNonLValueExprType(Context);
13939 CXXOperatorCallExpr *TheCall = CXXOperatorCallExpr::Create(
13940 Context, OO_Arrow, FnExpr.get(), Base, ResultTy, VK, OpLoc, FPOptions());
13942 if (CheckCallReturnType(Method->getReturnType(), OpLoc, TheCall, Method))
13943 return ExprError();
13945 if (CheckFunctionCall(Method, TheCall,
13946 Method->getType()->castAs<FunctionProtoType>()))
13947 return ExprError();
13949 return MaybeBindToTemporary(TheCall);
13952 /// BuildLiteralOperatorCall - Build a UserDefinedLiteral by creating a call to
13953 /// a literal operator described by the provided lookup results.
13954 ExprResult Sema::BuildLiteralOperatorCall(LookupResult &R,
13955 DeclarationNameInfo &SuffixInfo,
13956 ArrayRef<Expr*> Args,
13957 SourceLocation LitEndLoc,
13958 TemplateArgumentListInfo *TemplateArgs) {
13959 SourceLocation UDSuffixLoc = SuffixInfo.getCXXLiteralOperatorNameLoc();
13961 OverloadCandidateSet CandidateSet(UDSuffixLoc,
13962 OverloadCandidateSet::CSK_Normal);
13963 AddNonMemberOperatorCandidates(R.asUnresolvedSet(), Args, CandidateSet,
13966 bool HadMultipleCandidates = (CandidateSet.size() > 1);
13968 // Perform overload resolution. This will usually be trivial, but might need
13969 // to perform substitutions for a literal operator template.
13970 OverloadCandidateSet::iterator Best;
13971 switch (CandidateSet.BestViableFunction(*this, UDSuffixLoc, Best)) {
13976 case OR_No_Viable_Function:
13977 CandidateSet.NoteCandidates(
13978 PartialDiagnosticAt(UDSuffixLoc,
13979 PDiag(diag::err_ovl_no_viable_function_in_call)
13980 << R.getLookupName()),
13981 *this, OCD_AllCandidates, Args);
13982 return ExprError();
13985 CandidateSet.NoteCandidates(
13986 PartialDiagnosticAt(R.getNameLoc(), PDiag(diag::err_ovl_ambiguous_call)
13987 << R.getLookupName()),
13988 *this, OCD_ViableCandidates, Args);
13989 return ExprError();
13992 FunctionDecl *FD = Best->Function;
13993 ExprResult Fn = CreateFunctionRefExpr(*this, FD, Best->FoundDecl,
13994 nullptr, HadMultipleCandidates,
13995 SuffixInfo.getLoc(),
13996 SuffixInfo.getInfo());
13997 if (Fn.isInvalid())
14000 // Check the argument types. This should almost always be a no-op, except
14001 // that array-to-pointer decay is applied to string literals.
14003 for (unsigned ArgIdx = 0, N = Args.size(); ArgIdx != N; ++ArgIdx) {
14004 ExprResult InputInit = PerformCopyInitialization(
14005 InitializedEntity::InitializeParameter(Context, FD->getParamDecl(ArgIdx)),
14006 SourceLocation(), Args[ArgIdx]);
14007 if (InputInit.isInvalid())
14009 ConvArgs[ArgIdx] = InputInit.get();
14012 QualType ResultTy = FD->getReturnType();
14013 ExprValueKind VK = Expr::getValueKindForType(ResultTy);
14014 ResultTy = ResultTy.getNonLValueExprType(Context);
14016 UserDefinedLiteral *UDL = UserDefinedLiteral::Create(
14017 Context, Fn.get(), llvm::makeArrayRef(ConvArgs, Args.size()), ResultTy,
14018 VK, LitEndLoc, UDSuffixLoc);
14020 if (CheckCallReturnType(FD->getReturnType(), UDSuffixLoc, UDL, FD))
14021 return ExprError();
14023 if (CheckFunctionCall(FD, UDL, nullptr))
14024 return ExprError();
14026 return MaybeBindToTemporary(UDL);
14029 /// Build a call to 'begin' or 'end' for a C++11 for-range statement. If the
14030 /// given LookupResult is non-empty, it is assumed to describe a member which
14031 /// will be invoked. Otherwise, the function will be found via argument
14032 /// dependent lookup.
14033 /// CallExpr is set to a valid expression and FRS_Success returned on success,
14034 /// otherwise CallExpr is set to ExprError() and some non-success value
14036 Sema::ForRangeStatus
14037 Sema::BuildForRangeBeginEndCall(SourceLocation Loc,
14038 SourceLocation RangeLoc,
14039 const DeclarationNameInfo &NameInfo,
14040 LookupResult &MemberLookup,
14041 OverloadCandidateSet *CandidateSet,
14042 Expr *Range, ExprResult *CallExpr) {
14043 Scope *S = nullptr;
14045 CandidateSet->clear(OverloadCandidateSet::CSK_Normal);
14046 if (!MemberLookup.empty()) {
14047 ExprResult MemberRef =
14048 BuildMemberReferenceExpr(Range, Range->getType(), Loc,
14049 /*IsPtr=*/false, CXXScopeSpec(),
14050 /*TemplateKWLoc=*/SourceLocation(),
14051 /*FirstQualifierInScope=*/nullptr,
14053 /*TemplateArgs=*/nullptr, S);
14054 if (MemberRef.isInvalid()) {
14055 *CallExpr = ExprError();
14056 return FRS_DiagnosticIssued;
14058 *CallExpr = BuildCallExpr(S, MemberRef.get(), Loc, None, Loc, nullptr);
14059 if (CallExpr->isInvalid()) {
14060 *CallExpr = ExprError();
14061 return FRS_DiagnosticIssued;
14064 UnresolvedSet<0> FoundNames;
14065 UnresolvedLookupExpr *Fn =
14066 UnresolvedLookupExpr::Create(Context, /*NamingClass=*/nullptr,
14067 NestedNameSpecifierLoc(), NameInfo,
14068 /*NeedsADL=*/true, /*Overloaded=*/false,
14069 FoundNames.begin(), FoundNames.end());
14071 bool CandidateSetError = buildOverloadedCallSet(S, Fn, Fn, Range, Loc,
14072 CandidateSet, CallExpr);
14073 if (CandidateSet->empty() || CandidateSetError) {
14074 *CallExpr = ExprError();
14075 return FRS_NoViableFunction;
14077 OverloadCandidateSet::iterator Best;
14078 OverloadingResult OverloadResult =
14079 CandidateSet->BestViableFunction(*this, Fn->getBeginLoc(), Best);
14081 if (OverloadResult == OR_No_Viable_Function) {
14082 *CallExpr = ExprError();
14083 return FRS_NoViableFunction;
14085 *CallExpr = FinishOverloadedCallExpr(*this, S, Fn, Fn, Loc, Range,
14086 Loc, nullptr, CandidateSet, &Best,
14088 /*AllowTypoCorrection=*/false);
14089 if (CallExpr->isInvalid() || OverloadResult != OR_Success) {
14090 *CallExpr = ExprError();
14091 return FRS_DiagnosticIssued;
14094 return FRS_Success;
14098 /// FixOverloadedFunctionReference - E is an expression that refers to
14099 /// a C++ overloaded function (possibly with some parentheses and
14100 /// perhaps a '&' around it). We have resolved the overloaded function
14101 /// to the function declaration Fn, so patch up the expression E to
14102 /// refer (possibly indirectly) to Fn. Returns the new expr.
14103 Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found,
14104 FunctionDecl *Fn) {
14105 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
14106 Expr *SubExpr = FixOverloadedFunctionReference(PE->getSubExpr(),
14108 if (SubExpr == PE->getSubExpr())
14111 return new (Context) ParenExpr(PE->getLParen(), PE->getRParen(), SubExpr);
14114 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
14115 Expr *SubExpr = FixOverloadedFunctionReference(ICE->getSubExpr(),
14117 assert(Context.hasSameType(ICE->getSubExpr()->getType(),
14118 SubExpr->getType()) &&
14119 "Implicit cast type cannot be determined from overload");
14120 assert(ICE->path_empty() && "fixing up hierarchy conversion?");
14121 if (SubExpr == ICE->getSubExpr())
14124 return ImplicitCastExpr::Create(Context, ICE->getType(),
14125 ICE->getCastKind(),
14127 ICE->getValueKind());
14130 if (auto *GSE = dyn_cast<GenericSelectionExpr>(E)) {
14131 if (!GSE->isResultDependent()) {
14133 FixOverloadedFunctionReference(GSE->getResultExpr(), Found, Fn);
14134 if (SubExpr == GSE->getResultExpr())
14137 // Replace the resulting type information before rebuilding the generic
14138 // selection expression.
14139 ArrayRef<Expr *> A = GSE->getAssocExprs();
14140 SmallVector<Expr *, 4> AssocExprs(A.begin(), A.end());
14141 unsigned ResultIdx = GSE->getResultIndex();
14142 AssocExprs[ResultIdx] = SubExpr;
14144 return GenericSelectionExpr::Create(
14145 Context, GSE->getGenericLoc(), GSE->getControllingExpr(),
14146 GSE->getAssocTypeSourceInfos(), AssocExprs, GSE->getDefaultLoc(),
14147 GSE->getRParenLoc(), GSE->containsUnexpandedParameterPack(),
14150 // Rather than fall through to the unreachable, return the original generic
14151 // selection expression.
14155 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) {
14156 assert(UnOp->getOpcode() == UO_AddrOf &&
14157 "Can only take the address of an overloaded function");
14158 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) {
14159 if (Method->isStatic()) {
14160 // Do nothing: static member functions aren't any different
14161 // from non-member functions.
14163 // Fix the subexpression, which really has to be an
14164 // UnresolvedLookupExpr holding an overloaded member function
14166 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(),
14168 if (SubExpr == UnOp->getSubExpr())
14171 assert(isa<DeclRefExpr>(SubExpr)
14172 && "fixed to something other than a decl ref");
14173 assert(cast<DeclRefExpr>(SubExpr)->getQualifier()
14174 && "fixed to a member ref with no nested name qualifier");
14176 // We have taken the address of a pointer to member
14177 // function. Perform the computation here so that we get the
14178 // appropriate pointer to member type.
14180 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext()));
14181 QualType MemPtrType
14182 = Context.getMemberPointerType(Fn->getType(), ClassType.getTypePtr());
14183 // Under the MS ABI, lock down the inheritance model now.
14184 if (Context.getTargetInfo().getCXXABI().isMicrosoft())
14185 (void)isCompleteType(UnOp->getOperatorLoc(), MemPtrType);
14187 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType,
14188 VK_RValue, OK_Ordinary,
14189 UnOp->getOperatorLoc(), false);
14192 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(),
14194 if (SubExpr == UnOp->getSubExpr())
14197 return new (Context) UnaryOperator(SubExpr, UO_AddrOf,
14198 Context.getPointerType(SubExpr->getType()),
14199 VK_RValue, OK_Ordinary,
14200 UnOp->getOperatorLoc(), false);
14203 // C++ [except.spec]p17:
14204 // An exception-specification is considered to be needed when:
14205 // - in an expression the function is the unique lookup result or the
14206 // selected member of a set of overloaded functions
14207 if (auto *FPT = Fn->getType()->getAs<FunctionProtoType>())
14208 ResolveExceptionSpec(E->getExprLoc(), FPT);
14210 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) {
14211 // FIXME: avoid copy.
14212 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = nullptr;
14213 if (ULE->hasExplicitTemplateArgs()) {
14214 ULE->copyTemplateArgumentsInto(TemplateArgsBuffer);
14215 TemplateArgs = &TemplateArgsBuffer;
14219 BuildDeclRefExpr(Fn, Fn->getType(), VK_LValue, ULE->getNameInfo(),
14220 ULE->getQualifierLoc(), Found.getDecl(),
14221 ULE->getTemplateKeywordLoc(), TemplateArgs);
14222 DRE->setHadMultipleCandidates(ULE->getNumDecls() > 1);
14226 if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) {
14227 // FIXME: avoid copy.
14228 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = nullptr;
14229 if (MemExpr->hasExplicitTemplateArgs()) {
14230 MemExpr->copyTemplateArgumentsInto(TemplateArgsBuffer);
14231 TemplateArgs = &TemplateArgsBuffer;
14236 // If we're filling in a static method where we used to have an
14237 // implicit member access, rewrite to a simple decl ref.
14238 if (MemExpr->isImplicitAccess()) {
14239 if (cast<CXXMethodDecl>(Fn)->isStatic()) {
14240 DeclRefExpr *DRE = BuildDeclRefExpr(
14241 Fn, Fn->getType(), VK_LValue, MemExpr->getNameInfo(),
14242 MemExpr->getQualifierLoc(), Found.getDecl(),
14243 MemExpr->getTemplateKeywordLoc(), TemplateArgs);
14244 DRE->setHadMultipleCandidates(MemExpr->getNumDecls() > 1);
14247 SourceLocation Loc = MemExpr->getMemberLoc();
14248 if (MemExpr->getQualifier())
14249 Loc = MemExpr->getQualifierLoc().getBeginLoc();
14251 BuildCXXThisExpr(Loc, MemExpr->getBaseType(), /*IsImplicit=*/true);
14254 Base = MemExpr->getBase();
14256 ExprValueKind valueKind;
14258 if (cast<CXXMethodDecl>(Fn)->isStatic()) {
14259 valueKind = VK_LValue;
14260 type = Fn->getType();
14262 valueKind = VK_RValue;
14263 type = Context.BoundMemberTy;
14266 return BuildMemberExpr(
14267 Base, MemExpr->isArrow(), MemExpr->getOperatorLoc(),
14268 MemExpr->getQualifierLoc(), MemExpr->getTemplateKeywordLoc(), Fn, Found,
14269 /*HadMultipleCandidates=*/true, MemExpr->getMemberNameInfo(),
14270 type, valueKind, OK_Ordinary, TemplateArgs);
14273 llvm_unreachable("Invalid reference to overloaded function");
14276 ExprResult Sema::FixOverloadedFunctionReference(ExprResult E,
14277 DeclAccessPair Found,
14278 FunctionDecl *Fn) {
14279 return FixOverloadedFunctionReference(E.get(), Found, Fn);