Index: clang/docs/ReleaseNotes.rst =================================================================== --- clang/docs/ReleaseNotes.rst +++ clang/docs/ReleaseNotes.rst @@ -395,10 +395,11 @@ - No longer attempt to evaluate a consteval UDL function call at runtime when it is called through a template instantiation. This fixes `Issue 54578 `_. - -- Implemented ``__builtin_source_location()``, which enables library support - for ``std::source_location``. - +- Implemented `__builtin_source_location()` which enables library support for std::source_location. +- Clang now correctly delays the instantiation of function constraints until + the time of checking, which should now allow the libstdc++ ranges implementation + to work for at least trivial examples. This fixes + `Issue 44178 `_. - The mangling scheme for C++20 modules has incompatibly changed. The initial mangling was discovered not to be reversible, and the weak ownership design decision did not give the backwards compatibility Index: clang/include/clang/AST/Decl.h =================================================================== --- clang/include/clang/AST/Decl.h +++ clang/include/clang/AST/Decl.h @@ -1890,7 +1890,9 @@ TK_FunctionTemplateSpecialization, // A function template specialization that hasn't yet been resolved to a // particular specialized function template. - TK_DependentFunctionTemplateSpecialization + TK_DependentFunctionTemplateSpecialization, + // A non templated function which is in a dependent scope. + TK_DependentNonTemplate }; /// Stashed information about a defaulted function definition whose body has @@ -1939,20 +1941,21 @@ /// The template or declaration that this declaration /// describes or was instantiated from, respectively. /// - /// For non-templates, this value will be NULL. For function - /// declarations that describe a function template, this will be a - /// pointer to a FunctionTemplateDecl. For member functions - /// of class template specializations, this will be a MemberSpecializationInfo - /// pointer containing information about the specialization. - /// For function template specializations, this will be a - /// FunctionTemplateSpecializationInfo, which contains information about - /// the template being specialized and the template arguments involved in - /// that specialization. - llvm::PointerUnion - TemplateOrSpecialization; + TemplateOrSpecialization; /// Provides source/type location info for the declaration name embedded in /// the DeclaratorDecl base class. @@ -2688,6 +2691,11 @@ setInstantiationOfMemberFunction(getASTContext(), FD, TSK); } + /// Specify that this function declaration was instantiated from FunctionDecl + /// FD. This is only used if this is a function declaration declared locally + /// inside of a function template. + void setInstantiatedFromDecl(FunctionDecl *FD); + /// Retrieves the function template that is described by this /// function declaration. /// @@ -2702,6 +2710,8 @@ /// FunctionTemplateDecl from a FunctionDecl. FunctionTemplateDecl *getDescribedFunctionTemplate() const; + FunctionDecl *getInstantiatedFromDecl() const; + void setDescribedFunctionTemplate(FunctionTemplateDecl *Template); /// Determine whether this function is a function template Index: clang/include/clang/AST/DeclBase.h =================================================================== --- clang/include/clang/AST/DeclBase.h +++ clang/include/clang/AST/DeclBase.h @@ -906,6 +906,14 @@ const_cast(this)->getParentFunctionOrMethod()); } + /// Does the same thing as getParentFunctionOrMethod, except starts with the + /// lexical declaration context instead. + const DeclContext *getLexicalParentFunctionOrMethod() const; + DeclContext *getLexicalParentFunctionOrMethod() { + return const_cast( + const_cast(this)->getLexicalParentFunctionOrMethod()); + } + /// Retrieves the "canonical" declaration of the given declaration. virtual Decl *getCanonicalDecl() { return this; } const Decl *getCanonicalDecl() const { Index: clang/include/clang/Sema/Sema.h =================================================================== --- clang/include/clang/Sema/Sema.h +++ clang/include/clang/Sema/Sema.h @@ -3555,6 +3555,11 @@ bool ConsiderCudaAttrs = true, bool ConsiderRequiresClauses = true); + // Calculates whether the expression Constraint depends on an enclosing + // template, for the purposes of [temp.friend] p9. + bool ConstraintExpressionDependsOnEnclosingTemplate(unsigned TemplateDepth, + const Expr *Constraint); + enum class AllowedExplicit { /// Allow no explicit functions to be used. None, @@ -6995,7 +7000,36 @@ LocalInstantiationScope &Scope, const MultiLevelTemplateArgumentList &TemplateArgs); + /// used by SetupConstraintCheckingTemplateArgumentsAndScope to recursively(in + /// the case of lambdas) set up the LocalInstantiationScope of the current + /// function. + bool SetupConstraintScope( + FunctionDecl *FD, llvm::Optional> TemplateArgs, + MultiLevelTemplateArgumentList MLTAL, LocalInstantiationScope &Scope); + + /// Used during constraint checking, sets up the constraint template arguemnt + /// lists, and calls SetupConstraintScope to set up the + /// LocalInstantiationScope to have the proper set of ParVarDecls configured. + llvm::Optional + SetupConstraintCheckingTemplateArgumentsAndScope( + FunctionDecl *FD, llvm::Optional> TemplateArgs, + LocalInstantiationScope &Scope); + + /* + // Keep track of whether we are evaluating a constraint. + unsigned ConstraintEvaluationDepth = 0; + + class ConstraintEvalRAII { + Sema &S; + + public: + ConstraintEvalRAII(Sema &S) : S(S) { ++S.ConstraintEvaluationDepth; } + ~ConstraintEvalRAII() { --S.ConstraintEvaluationDepth; } + }; + */ + public: + //bool IsEvaluatingAConstraint() { return ConstraintEvaluationDepth > 0; } const NormalizedConstraint * getNormalizedAssociatedConstraints( NamedDecl *ConstrainedDecl, ArrayRef AssociatedConstraints); @@ -7025,8 +7059,10 @@ /// check (either a concept or a constrained entity). /// \param ConstraintExprs a list of constraint expressions, treated as if /// they were 'AND'ed together. - /// \param TemplateArgs the list of template arguments to substitute into the - /// constraint expression. + /// \param TemplateArgList the multi-level list of template arguments to + /// substitute into the constraint expression. This should be relative to the + /// top-level (hence multi-level), since we need to instantiate fully at the + /// time of checking. /// \param TemplateIDRange The source range of the template id that /// caused the constraints check. /// \param Satisfaction if true is returned, will contain details of the @@ -7036,7 +7072,40 @@ /// false otherwise. bool CheckConstraintSatisfaction( const NamedDecl *Template, ArrayRef ConstraintExprs, - ArrayRef TemplateArgs, + const MultiLevelTemplateArgumentList &TemplateArgList, + SourceRange TemplateIDRange, ConstraintSatisfaction &Satisfaction) { + llvm::SmallVector Converted; + return CheckConstraintSatisfaction(Template, ConstraintExprs, Converted, + TemplateArgList, TemplateIDRange, + Satisfaction); + } + + /// \brief Check whether the given list of constraint expressions are + /// satisfied (as if in a 'conjunction') given template arguments. + /// Additionally, takes an empty list of Expressions which is populated with + /// the instantiated versions of the ConstraintExprs. + /// \param Template the template-like entity that triggered the constraints + /// check (either a concept or a constrained entity). + /// \param ConstraintExprs a list of constraint expressions, treated as if + /// they were 'AND'ed together. + /// \param ConvertedConstraints a out parameter that will get populated with + /// the instantiated version of the ConstraintExprs if we successfully checked + /// satisfaction. + /// \param TemplateArgList the multi-level list of template arguments to + /// substitute into the constraint expression. This should be relative to the + /// top-level (hence multi-level), since we need to instantiate fully at the + /// time of checking. + /// \param TemplateIDRange The source range of the template id that + /// caused the constraints check. + /// \param Satisfaction if true is returned, will contain details of the + /// satisfaction, with enough information to diagnose an unsatisfied + /// expression. + /// \returns true if an error occurred and satisfaction could not be checked, + /// false otherwise. + bool CheckConstraintSatisfaction( + const NamedDecl *Template, ArrayRef ConstraintExprs, + llvm::SmallVectorImpl &ConvertedConstraints, + const MultiLevelTemplateArgumentList &TemplateArgList, SourceRange TemplateIDRange, ConstraintSatisfaction &Satisfaction); /// \brief Check whether the given non-dependent constraint expression is @@ -7072,9 +7141,9 @@ /// /// \returns true if the constrains are not satisfied or could not be checked /// for satisfaction, false if the constraints are satisfied. - bool EnsureTemplateArgumentListConstraints(TemplateDecl *Template, - ArrayRef TemplateArgs, - SourceRange TemplateIDRange); + bool EnsureTemplateArgumentListConstraints( + TemplateDecl *Template, MultiLevelTemplateArgumentList TemplateArgs, + SourceRange TemplateIDRange); /// \brief Emit diagnostics explaining why a constraint expression was deemed /// unsatisfied. @@ -8808,7 +8877,8 @@ MultiLevelTemplateArgumentList getTemplateInstantiationArgs( const NamedDecl *D, const TemplateArgumentList *Innermost = nullptr, - bool RelativeToPrimary = false, const FunctionDecl *Pattern = nullptr); + bool RelativeToPrimary = false, const FunctionDecl *Pattern = nullptr, + bool LookBeyondLambda = false, bool IncludeContainingStruct = false); /// A context in which code is being synthesized (where a source location /// alone is not sufficient to identify the context). This covers template @@ -9541,6 +9611,11 @@ ExtParameterInfoBuilder &ParamInfos); ExprResult SubstExpr(Expr *E, const MultiLevelTemplateArgumentList &TemplateArgs); + // Unlike the above, this evaluates constraints, which should only happen at + // 'constraint checking' time. + ExprResult + SubstConstraintExpr(Expr *E, + const MultiLevelTemplateArgumentList &TemplateArgs); /// Substitute the given template arguments into a list of /// expressions, expanding pack expansions if required. @@ -9662,7 +9737,9 @@ const MultiLevelTemplateArgumentList &TemplateArgs); bool SubstTypeConstraint(TemplateTypeParmDecl *Inst, const TypeConstraint *TC, - const MultiLevelTemplateArgumentList &TemplateArgs); + const MultiLevelTemplateArgumentList &TemplateArgs, + bool isEvaluatingAConstraint + ); bool InstantiateDefaultArgument(SourceLocation CallLoc, FunctionDecl *FD, ParmVarDecl *Param); Index: clang/include/clang/Sema/Template.h =================================================================== --- clang/include/clang/Sema/Template.h +++ clang/include/clang/Sema/Template.h @@ -75,6 +75,9 @@ class MultiLevelTemplateArgumentList { /// The template argument list at a certain template depth using ArgList = ArrayRef; + using ArgListsIterator = SmallVector::iterator; + using ConstArgListsIterator = + SmallVector::const_iterator; /// The template argument lists, stored from the innermost template /// argument list (first) to the outermost template argument list (last). @@ -121,6 +124,12 @@ return TemplateArgumentLists.size(); } + /// Determine the number of substituted args at 'Depth'. + unsigned getNumSubstitutedArgs(unsigned Depth) const { + assert(NumRetainedOuterLevels <= Depth && Depth < getNumLevels()); + return TemplateArgumentLists[getNumLevels() - Depth - 1].size(); + } + unsigned getNumRetainedOuterLevels() const { return NumRetainedOuterLevels; } @@ -158,6 +167,14 @@ return !(*this)(Depth, Index).isNull(); } + bool isAnyArgInstantiationDependent() const { + for (ArgList List : TemplateArgumentLists) + for (const TemplateArgument &TA : List) + if (TA.isInstantiationDependent()) + return true; + return false; + } + /// Clear out a specific template argument. void setArgument(unsigned Depth, unsigned Index, TemplateArgument Arg) { @@ -183,6 +200,14 @@ TemplateArgumentLists.push_back(Args); } + /// Replaces the current 'innermost' level with the provided argument list. + /// This is useful for type deduction cases where we need to get the entire + /// list from the AST, but then add the deduced innermost list. + void replaceInnermostTemplateArguments(ArgList Args) { + assert(TemplateArgumentLists.size() > 0 && "Replacing in an empty list?"); + TemplateArgumentLists[0] = Args; + } + /// Add an outermost level that we are not substituting. We have no /// arguments at this level, and do not remove it from the depth of inner /// template parameters that we instantiate. @@ -197,6 +222,16 @@ const ArgList &getInnermost() const { return TemplateArgumentLists.front(); } + + /// Retrieve the outermost template argument list. + const ArgList &getOutermost() const { return TemplateArgumentLists.back(); } + + ArgListsIterator begin() { return TemplateArgumentLists.begin(); } + ConstArgListsIterator begin() const { + return TemplateArgumentLists.begin(); + } + ArgListsIterator end() { return TemplateArgumentLists.end(); } + ConstArgListsIterator end() const { return TemplateArgumentLists.end(); } }; /// The context in which partial ordering of function templates occurs. @@ -469,6 +504,7 @@ const MultiLevelTemplateArgumentList &TemplateArgs; Sema::LateInstantiatedAttrVec* LateAttrs = nullptr; LocalInstantiationScope *StartingScope = nullptr; + bool EvaluatingAConstraint = false; /// A list of out-of-line class template partial /// specializations that will need to be instantiated after the @@ -491,6 +527,10 @@ : SemaRef(SemaRef), SubstIndex(SemaRef, SemaRef.ArgumentPackSubstitutionIndex), Owner(Owner), TemplateArgs(TemplateArgs) {} + // TODO: ERICH: make part of the ctor? + void SetEvalConstraint(bool b) { + EvaluatingAConstraint = b; + } // Define all the decl visitors using DeclNodes.inc #define DECL(DERIVED, BASE) \ Index: clang/lib/AST/ASTImporter.cpp =================================================================== --- clang/lib/AST/ASTImporter.cpp +++ clang/lib/AST/ASTImporter.cpp @@ -3111,6 +3111,11 @@ case FunctionDecl::TK_FunctionTemplate: return Error::success(); + case FunctionDecl::TK_DependentNonTemplate: + if (Expected InstFDOrErr = + import(FromFD->getInstantiatedFromDecl())) + ToFD->setInstantiatedFromDecl(*InstFDOrErr); + return Error::success(); case FunctionDecl::TK_MemberSpecialization: { TemplateSpecializationKind TSK = FromFD->getTemplateSpecializationKind(); Index: clang/lib/AST/Decl.cpp =================================================================== --- clang/lib/AST/Decl.cpp +++ clang/lib/AST/Decl.cpp @@ -3729,8 +3729,12 @@ FunctionDecl::TemplatedKind FunctionDecl::getTemplatedKind() const { if (TemplateOrSpecialization.isNull()) return TK_NonTemplate; - if (TemplateOrSpecialization.is()) + if (auto *ND = TemplateOrSpecialization.dyn_cast()) { + if (isa(ND)) + return TK_DependentNonTemplate; + assert(isa(ND) && "No other types it could be?"); return TK_FunctionTemplate; + } if (TemplateOrSpecialization.is()) return TK_MemberSpecialization; if (TemplateOrSpecialization.is()) @@ -3771,13 +3775,26 @@ } FunctionTemplateDecl *FunctionDecl::getDescribedFunctionTemplate() const { - return TemplateOrSpecialization.dyn_cast(); + return dyn_cast_or_null( + TemplateOrSpecialization.dyn_cast()); } -void FunctionDecl::setDescribedFunctionTemplate(FunctionTemplateDecl *Template) { +void FunctionDecl::setDescribedFunctionTemplate( + FunctionTemplateDecl *Template) { assert(TemplateOrSpecialization.isNull() && "Member function is already a specialization"); - TemplateOrSpecialization = Template; + TemplateOrSpecialization = static_cast(Template); +} + +void FunctionDecl::setInstantiatedFromDecl(FunctionDecl *FD) { + assert(TemplateOrSpecialization.isNull() && + "function is already a specialization"); + TemplateOrSpecialization = static_cast(FD); +} + +FunctionDecl *FunctionDecl::getInstantiatedFromDecl() const { + return dyn_cast_or_null( + TemplateOrSpecialization.dyn_cast()); } bool FunctionDecl::isImplicitlyInstantiable() const { Index: clang/lib/AST/DeclBase.cpp =================================================================== --- clang/lib/AST/DeclBase.cpp +++ clang/lib/AST/DeclBase.cpp @@ -293,6 +293,16 @@ return nullptr; } +const DeclContext *Decl::getLexicalParentFunctionOrMethod() const { + for (const DeclContext *DC = getLexicalDeclContext(); + DC && !DC->isTranslationUnit() && !DC->isNamespace(); + DC = DC->getParent()) + if (DC->isFunctionOrMethod()) + return DC; + + return nullptr; +} + //===----------------------------------------------------------------------===// // PrettyStackTraceDecl Implementation //===----------------------------------------------------------------------===// Index: clang/lib/ExtractAPI/ExtractAPIConsumer.cpp =================================================================== --- clang/lib/ExtractAPI/ExtractAPIConsumer.cpp +++ clang/lib/ExtractAPI/ExtractAPIConsumer.cpp @@ -303,6 +303,7 @@ // Skip templated functions. switch (Decl->getTemplatedKind()) { case FunctionDecl::TK_NonTemplate: + case FunctionDecl::TK_DependentNonTemplate: break; case FunctionDecl::TK_MemberSpecialization: case FunctionDecl::TK_FunctionTemplateSpecialization: Index: clang/lib/Sema/SemaConcept.cpp =================================================================== --- clang/lib/Sema/SemaConcept.cpp +++ clang/lib/Sema/SemaConcept.cpp @@ -30,6 +30,7 @@ namespace { class LogicalBinOp { + SourceLocation Loc; OverloadedOperatorKind Op = OO_None; const Expr *LHS = nullptr; const Expr *RHS = nullptr; @@ -40,12 +41,14 @@ Op = BinaryOperator::getOverloadedOperator(BO->getOpcode()); LHS = BO->getLHS(); RHS = BO->getRHS(); + Loc = BO->getExprLoc(); } else if (auto *OO = dyn_cast(E)) { // If OO is not || or && it might not have exactly 2 arguments. if (OO->getNumArgs() == 2) { Op = OO->getOperator(); LHS = OO->getArg(0); RHS = OO->getArg(1); + Loc = OO->getOperatorLoc(); } } } @@ -56,6 +59,25 @@ const Expr *getLHS() const { return LHS; } const Expr *getRHS() const { return RHS; } + + ExprResult recreateBinOp(Sema &SemaRef, ExprResult LHS) { + return recreateBinOp(SemaRef, LHS, const_cast(getRHS())); + } + + ExprResult recreateBinOp(Sema &SemaRef, ExprResult LHS, ExprResult RHS) { + assert((isAnd() || isOr()) && "Not the right kind of op?"); + assert((!LHS.isInvalid() && !RHS.isInvalid()) && "not good expressions?"); + + if (!LHS.isUsable() || !RHS.isUsable()) + return ExprEmpty(); + + // We should just be able to 'normalize' these to the builtin Binary + // Operator, since that is how they are evaluated in constriant checks. + return BinaryOperator::Create(SemaRef.Context, LHS.get(), RHS.get(), + BinaryOperator::getOverloadedOpcode(Op), + SemaRef.Context.BoolTy, VK_PRValue, + OK_Ordinary, Loc, FPOptionsOverride{}); + } }; } @@ -122,16 +144,18 @@ } template -static bool +static ExprResult calculateConstraintSatisfaction(Sema &S, const Expr *ConstraintExpr, ConstraintSatisfaction &Satisfaction, AtomicEvaluator &&Evaluator) { ConstraintExpr = ConstraintExpr->IgnoreParenImpCasts(); if (LogicalBinOp BO = ConstraintExpr) { - if (calculateConstraintSatisfaction(S, BO.getLHS(), Satisfaction, - Evaluator)) - return true; + ExprResult LHSRes = calculateConstraintSatisfaction( + S, BO.getLHS(), Satisfaction, Evaluator); + + if (LHSRes.isInvalid()) + return ExprError(); bool IsLHSSatisfied = Satisfaction.IsSatisfied; @@ -142,7 +166,7 @@ // is checked. If that is satisfied, the disjunction is satisfied. // Otherwise, the disjunction is satisfied if and only if the second // operand is satisfied. - return false; + return BO.recreateBinOp(S, LHSRes); if (BO.isAnd() && !IsLHSSatisfied) // [temp.constr.op] p2 @@ -151,12 +175,19 @@ // is checked. If that is not satisfied, the conjunction is not // satisfied. Otherwise, the conjunction is satisfied if and only if // the second operand is satisfied. - return false; + return BO.recreateBinOp(S, LHSRes); - return calculateConstraintSatisfaction( + ExprResult RHSRes = calculateConstraintSatisfaction( S, BO.getRHS(), Satisfaction, std::forward(Evaluator)); + if (RHSRes.isInvalid()) + return ExprError(); + + return BO.recreateBinOp(S, LHSRes, RHSRes); } else if (auto *C = dyn_cast(ConstraintExpr)) { - return calculateConstraintSatisfaction(S, C->getSubExpr(), Satisfaction, + // These aren't evaluated, so we don't care about cleanups, so we can just + // evaluate these as if the cleanups didn't exist. + return calculateConstraintSatisfaction( + S, C->getSubExpr(), Satisfaction, std::forward(Evaluator)); } @@ -164,11 +195,11 @@ ExprResult SubstitutedAtomicExpr = Evaluator(ConstraintExpr); if (SubstitutedAtomicExpr.isInvalid()) - return true; + return ExprError(); if (!SubstitutedAtomicExpr.isUsable()) // Evaluator has decided satisfaction without yielding an expression. - return false; + return ExprEmpty(); EnterExpressionEvaluationContext ConstantEvaluated( S, Sema::ExpressionEvaluationContext::ConstantEvaluated); @@ -185,7 +216,7 @@ << SubstitutedAtomicExpr.get()->getSourceRange(); for (const PartialDiagnosticAt &PDiag : EvaluationDiags) S.Diag(PDiag.first, PDiag.second); - return true; + return ExprError(); } assert(EvalResult.Val.isInt() && @@ -195,13 +226,13 @@ Satisfaction.Details.emplace_back(ConstraintExpr, SubstitutedAtomicExpr.get()); - return false; + return SubstitutedAtomicExpr; } -static bool calculateConstraintSatisfaction( - Sema &S, const NamedDecl *Template, ArrayRef TemplateArgs, - SourceLocation TemplateNameLoc, MultiLevelTemplateArgumentList &MLTAL, - const Expr *ConstraintExpr, ConstraintSatisfaction &Satisfaction) { +static ExprResult calculateConstraintSatisfaction( + Sema &S, const NamedDecl *Template, SourceLocation TemplateNameLoc, + const MultiLevelTemplateArgumentList &MLTAL, const Expr *ConstraintExpr, + ConstraintSatisfaction &Satisfaction) { return calculateConstraintSatisfaction( S, ConstraintExpr, Satisfaction, [&](const Expr *AtomicExpr) { EnterExpressionEvaluationContext ConstantEvaluated( @@ -219,8 +250,8 @@ return ExprError(); // We do not want error diagnostics escaping here. Sema::SFINAETrap Trap(S); - SubstitutedExpression = S.SubstExpr(const_cast(AtomicExpr), - MLTAL); + SubstitutedExpression = + S.SubstConstraintExpr(const_cast(AtomicExpr), MLTAL); // Substitution might have stripped off a contextual conversion to // bool if this is the operand of an '&&' or '||'. For example, we // might lose an lvalue-to-rvalue conversion here. If so, put it back @@ -268,72 +299,92 @@ }); } -static bool CheckConstraintSatisfaction(Sema &S, const NamedDecl *Template, - ArrayRef ConstraintExprs, - ArrayRef TemplateArgs, - SourceRange TemplateIDRange, - ConstraintSatisfaction &Satisfaction) { +static bool CheckConstraintSatisfaction( + Sema &S, const NamedDecl *Template, ArrayRef ConstraintExprs, + llvm::SmallVectorImpl &Converted, + const MultiLevelTemplateArgumentList &TemplateArgsList, + SourceRange TemplateIDRange, ConstraintSatisfaction &Satisfaction) { if (ConstraintExprs.empty()) { Satisfaction.IsSatisfied = true; return false; } - for (auto& Arg : TemplateArgs) - if (Arg.isInstantiationDependent()) { - // No need to check satisfaction for dependent constraint expressions. - Satisfaction.IsSatisfied = true; - return false; - } + if (TemplateArgsList.isAnyArgInstantiationDependent()) { + // No need to check satisfaction for dependent constraint expressions. + Satisfaction.IsSatisfied = true; + return false; + } + + ArrayRef TemplateArgs = + TemplateArgsList.getNumSubstitutedLevels() > 0 + ? TemplateArgsList.getOutermost() + : ArrayRef{}; - Sema::InstantiatingTemplate Inst(S, TemplateIDRange.getBegin(), + Sema::InstantiatingTemplate Inst( + S, TemplateIDRange.getBegin(), Sema::InstantiatingTemplate::ConstraintsCheck{}, const_cast(Template), TemplateArgs, TemplateIDRange); if (Inst.isInvalid()) return true; - MultiLevelTemplateArgumentList MLTAL; - MLTAL.addOuterTemplateArguments(TemplateArgs); - for (const Expr *ConstraintExpr : ConstraintExprs) { - if (calculateConstraintSatisfaction(S, Template, TemplateArgs, - TemplateIDRange.getBegin(), MLTAL, - ConstraintExpr, Satisfaction)) + ExprResult Res = calculateConstraintSatisfaction( + S, Template, TemplateIDRange.getBegin(), TemplateArgsList, + ConstraintExpr, Satisfaction); + if (Res.isInvalid()) return true; - if (!Satisfaction.IsSatisfied) + + Converted.push_back(Res.get()); + if (!Satisfaction.IsSatisfied) { + // Backfill the 'converted' list with nulls so we can keep the Converted + // and unconverted lists in sync. + Converted.append(ConstraintExprs.size() - Converted.size(), nullptr); // [temp.constr.op] p2 - // [...] To determine if a conjunction is satisfied, the satisfaction - // of the first operand is checked. If that is not satisfied, the - // conjunction is not satisfied. [...] + // [...] To determine if a conjunction is satisfied, the satisfaction + // of the first operand is checked. If that is not satisfied, the + // conjunction is not satisfied. [...] return false; + } } return false; } bool Sema::CheckConstraintSatisfaction( const NamedDecl *Template, ArrayRef ConstraintExprs, - ArrayRef TemplateArgs, SourceRange TemplateIDRange, - ConstraintSatisfaction &OutSatisfaction) { + llvm::SmallVectorImpl &ConvertedConstraints, + const MultiLevelTemplateArgumentList &TemplateArgsList, + SourceRange TemplateIDRange, ConstraintSatisfaction &OutSatisfaction) { if (ConstraintExprs.empty()) { OutSatisfaction.IsSatisfied = true; return false; } if (!Template) { return ::CheckConstraintSatisfaction(*this, nullptr, ConstraintExprs, - TemplateArgs, TemplateIDRange, - OutSatisfaction); + ConvertedConstraints, TemplateArgsList, + TemplateIDRange, OutSatisfaction); } + + // A list of the template argument list flattened in a predictible manner for + // the purposes of caching. The ConstraintSatisfaction type is in AST so it + // has no access to the MultiLevelTemplateArgumentList, so this has to happen + // here. + llvm::SmallVector FlattenedArgs; + for (ArrayRef List : TemplateArgsList) + FlattenedArgs.insert(FlattenedArgs.end(), List.begin(), List.end()); + llvm::FoldingSetNodeID ID; - ConstraintSatisfaction::Profile(ID, Context, Template, TemplateArgs); + ConstraintSatisfaction::Profile(ID, Context, Template, FlattenedArgs); + void *InsertPos; if (auto *Cached = SatisfactionCache.FindNodeOrInsertPos(ID, InsertPos)) { OutSatisfaction = *Cached; return false; } auto Satisfaction = - std::make_unique(Template, TemplateArgs); + std::make_unique(Template, FlattenedArgs); if (::CheckConstraintSatisfaction(*this, Template, ConstraintExprs, - TemplateArgs, TemplateIDRange, - *Satisfaction)) { + ConvertedConstraints, TemplateArgsList, + TemplateIDRange, *Satisfaction)) { return true; } OutSatisfaction = *Satisfaction; @@ -347,20 +398,116 @@ bool Sema::CheckConstraintSatisfaction(const Expr *ConstraintExpr, ConstraintSatisfaction &Satisfaction) { return calculateConstraintSatisfaction( - *this, ConstraintExpr, Satisfaction, - [](const Expr *AtomicExpr) -> ExprResult { - return ExprResult(const_cast(AtomicExpr)); - }); + *this, ConstraintExpr, Satisfaction, + [](const Expr *AtomicExpr) -> ExprResult { + return ExprResult(const_cast(AtomicExpr)); + }) + .isInvalid(); +} + +bool Sema::SetupConstraintScope( + FunctionDecl *FD, llvm::Optional> TemplateArgs, + MultiLevelTemplateArgumentList MLTAL, LocalInstantiationScope &Scope) { + if (FD->isTemplateInstantiation() && FD->getPrimaryTemplate()) { + FunctionTemplateDecl *PrimaryTemplate = FD->getPrimaryTemplate(); + InstantiatingTemplate Inst( + *this, FD->getPointOfInstantiation(), + Sema::InstantiatingTemplate::ConstraintsCheck{}, PrimaryTemplate, + TemplateArgs ? *TemplateArgs : ArrayRef{}, + SourceRange()); + if (Inst.isInvalid()) + return true; + + // addInstantiatedParametersToScope creates a map of 'uninstantiated' to + // 'instantiated' parameters and adds it to the context. For the case where + // this function is a template being instantiated NOW, we also need to add + // the list of current template arguments to the list so that they also can + // be picked out of the map. + if (auto *SpecArgs = FD->getTemplateSpecializationArgs()) { + MultiLevelTemplateArgumentList JustTemplArgs(*SpecArgs); + if (addInstantiatedParametersToScope( + FD, PrimaryTemplate->getTemplatedDecl(), Scope, JustTemplArgs)) + return true; + } + + // If this is a member function, make sure we get the parameters that + // reference the original primary template. + if (const auto *FromMemTempl = + PrimaryTemplate->getInstantiatedFromMemberTemplate()) { + if (addInstantiatedParametersToScope(FD, FromMemTempl->getTemplatedDecl(), + Scope, MLTAL)) + return true; + } + + return false; + } + + if (FD->getTemplatedKind() == FunctionDecl::TK_MemberSpecialization || + FD->getTemplatedKind() == FunctionDecl::TK_DependentNonTemplate) { + FunctionDecl *InstantiatedFrom = + FD->getTemplatedKind() == FunctionDecl::TK_MemberSpecialization + ? FD->getInstantiatedFromMemberFunction() + : FD->getInstantiatedFromDecl(); + + InstantiatingTemplate Inst( + *this, FD->getPointOfInstantiation(), + Sema::InstantiatingTemplate::ConstraintsCheck{}, InstantiatedFrom, + TemplateArgs ? *TemplateArgs : ArrayRef{}, + SourceRange()); + if (Inst.isInvalid()) + return true; + + // Case where this was not a template, but instantiated as a + // child-function. + if (addInstantiatedParametersToScope(FD, InstantiatedFrom, Scope, MLTAL)) + return true; + } + + return false; +} + +// This function collects all of the template arguments for the purposes of +// constraint-instantiation and checking. +llvm::Optional +Sema::SetupConstraintCheckingTemplateArgumentsAndScope( + FunctionDecl *FD, llvm::Optional> TemplateArgs, + LocalInstantiationScope &Scope) { + MultiLevelTemplateArgumentList MLTAL; + + // Collect the list of template arguments relative to the 'primary' template. + // We need the entire list, since the constraint is completely uninstantiated + // at this point. + MLTAL = getTemplateInstantiationArgs(FD, nullptr, /*RelativeToPrimary*/ true, + /*Pattern*/ nullptr, + /*LookBeyondLambda*/ true); + if (SetupConstraintScope(FD, TemplateArgs, MLTAL, Scope)) + return {}; + + return MLTAL; } bool Sema::CheckFunctionConstraints(const FunctionDecl *FD, ConstraintSatisfaction &Satisfaction, SourceLocation UsageLoc) { - const Expr *RC = FD->getTrailingRequiresClause(); - if (RC->isInstantiationDependent()) { + // Don't check constraints if the function is dependent. Also don't check if + // this is a function template specialization, as the call to + // CheckinstantiatedFunctionTemplateConstraints after this will check it + // better. + if (FD->isDependentContext() || + FD->getTemplatedKind() == + FunctionDecl::TK_FunctionTemplateSpecialization) { Satisfaction.IsSatisfied = true; return false; } + + ContextRAII SavedContext{ + *this, cast( + const_cast(FD)->getNonClosureContext())}; + LocalInstantiationScope Scope(*this, true); + llvm::Optional MLTAL = + SetupConstraintCheckingTemplateArgumentsAndScope( + const_cast(FD), {}, Scope); + Qualifiers ThisQuals; CXXRecordDecl *Record = nullptr; if (auto *Method = dyn_cast(FD)) { @@ -371,14 +518,27 @@ // We substitute with empty arguments in order to rebuild the atomic // constraint in a constant-evaluated context. // FIXME: Should this be a dedicated TreeTransform? - return CheckConstraintSatisfaction( - FD, {RC}, /*TemplateArgs=*/{}, - SourceRange(UsageLoc.isValid() ? UsageLoc : FD->getLocation()), - Satisfaction); + const Expr *RC = FD->getTrailingRequiresClause(); + llvm::SmallVector Converted; + + if (CheckConstraintSatisfaction( + FD, {RC}, Converted, *MLTAL, + SourceRange(UsageLoc.isValid() ? UsageLoc : FD->getLocation()), + Satisfaction)) + return true; + + // FIXME: we need to do this for the function constraints for + // comparison of constraints to work, but do we also need to do it for + // CheckInstantiatedFunctionConstraints? That one is more difficult, but we + // seem to always just pick up the constraints from the primary template. + assert(Converted.size() <= 1 && "Got more expressions converted?"); + if (!Converted.empty() && Converted[0] != nullptr) + const_cast(FD)->setTrailingRequiresClause(Converted[0]); + return false; } bool Sema::EnsureTemplateArgumentListConstraints( - TemplateDecl *TD, ArrayRef TemplateArgs, + TemplateDecl *TD, MultiLevelTemplateArgumentList TemplateArgs, SourceRange TemplateIDRange) { ConstraintSatisfaction Satisfaction; llvm::SmallVector AssociatedConstraints; @@ -391,7 +551,8 @@ SmallString<128> TemplateArgString; TemplateArgString = " "; TemplateArgString += getTemplateArgumentBindingsText( - TD->getTemplateParameters(), TemplateArgs.data(), TemplateArgs.size()); + TD->getTemplateParameters(), TemplateArgs.getInnermost().data(), + TemplateArgs.getInnermost().size()); Diag(TemplateIDRange.getBegin(), diag::err_template_arg_list_constraints_not_satisfied) @@ -423,21 +584,13 @@ Sema::ContextRAII savedContext(*this, Decl); LocalInstantiationScope Scope(*this); - // If this is not an explicit specialization - we need to get the instantiated - // version of the template arguments and add them to scope for the - // substitution. - if (Decl->isTemplateInstantiation()) { - InstantiatingTemplate Inst(*this, Decl->getPointOfInstantiation(), - InstantiatingTemplate::ConstraintsCheck{}, Decl->getPrimaryTemplate(), - TemplateArgs, SourceRange()); - if (Inst.isInvalid()) - return true; - MultiLevelTemplateArgumentList MLTAL( - *Decl->getTemplateSpecializationArgs()); - if (addInstantiatedParametersToScope( - Decl, Decl->getPrimaryTemplate()->getTemplatedDecl(), Scope, MLTAL)) - return true; - } + Optional MLTAL = + SetupConstraintCheckingTemplateArgumentsAndScope(Decl, TemplateArgs, + Scope); + + if (!MLTAL) + return true; + Qualifiers ThisQuals; CXXRecordDecl *Record = nullptr; if (auto *Method = dyn_cast(Decl)) { @@ -445,7 +598,8 @@ Record = Method->getParent(); } CXXThisScopeRAII ThisScope(*this, Record, ThisQuals, Record != nullptr); - return CheckConstraintSatisfaction(Template, TemplateAC, TemplateArgs, + llvm::SmallVector Converted; + return CheckConstraintSatisfaction(Template, TemplateAC, Converted, *MLTAL, PointOfInstantiation, Satisfaction); } Index: clang/lib/Sema/SemaOverload.cpp =================================================================== --- clang/lib/Sema/SemaOverload.cpp +++ clang/lib/Sema/SemaOverload.cpp @@ -992,6 +992,78 @@ return false; } +// Figure out the to-translation-unit depth for this function declaration for +// the purpose of seeing if they differ by constraints. This isn't the same as +// getTemplateDepth, because it includes already instantiated parents. +static unsigned CalculateTemplateDepthForConstraints(Sema &S, + FunctionDecl *FD) { + MultiLevelTemplateArgumentList MLTAL = + S.getTemplateInstantiationArgs(FD, nullptr, /*RelativeToPrimary*/ true, + /*Pattern*/ nullptr, + /*LookBeyondLambda*/ true); + return MLTAL.getNumSubstitutedLevels(); +} + +// Friend definitions can appear identical but be different declarations based +// on the last sentence of the rule below (others included for clarification): +// C++20 [temp.friend] p9: A non-template friend declaration +// with a requires-clause shall be a definition. A friend function template +// with a constraint that depends on a template parameter from an enclosing +// template shall be a definition. Such a constrained friend function or +// function template declaration does not declare the same function or function +// template as a declaration in any other scope. +static bool FriendsDifferByConstraints(Sema &S, DeclContext *CurContext, + FunctionDecl *Old, + FunctionDecl *New, Scope *Scope) { + // If these aren't friends, than they aren't friends that differe by + // constraints. + if (!Old->getFriendObjectKind() || !New->getFriendObjectKind()) + return false; + + // If the the two functions share lexical declaration context, they are not in + // separate instantations, and thus in the same scope. + if (New->getLexicalDeclContext() == Old->getLexicalDeclContext()) + return false; + + if (!Old->getDescribedFunctionTemplate()) { + assert(!New->getDescribedFunctionTemplate() && + "How would these be the same if they aren't both templates?"); + + // If these friends don't have constraints, they aren't constrained, and + // thus don't fall under temp.friend p9. Else the simple presence of a + // constraint makes them unique. + return Old->getTrailingRequiresClause(); + } + + SmallVector OldAC; + Old->getDescribedFunctionTemplate()->getAssociatedConstraints(OldAC); + +#ifndef NDEBUG + SmallVector NewAC; + New->getDescribedFunctionTemplate()->getAssociatedConstraints(NewAC); + assert(OldAC.size() == NewAC.size() && + "Difference should have been noticed earlier if sizes of constraints " + "aren't the same"); +#endif + // If there are no constraints, these are not constrained friend function or + // friend function templates. + if (OldAC.size() == 0) + return false; + + unsigned OldTemplateDepth = CalculateTemplateDepthForConstraints(S, Old); + + // At this point, if the constrained function template declaration depends on + // a template parameter from an enclosing template, they are not the same + // function. Since these were deemed identical before we got here, we only + // have to look into 1 side to see if they refer to a containing template. + for (const Expr *Constraint : OldAC) + if (S.ConstraintExpressionDependsOnEnclosingTemplate(OldTemplateDepth, + Constraint)) + return true; + + return false; +} + /// Determine whether the given New declaration is an overload of the /// declarations in Old. This routine returns Ovl_Match or Ovl_NonFunction if /// New and Old cannot be overloaded, e.g., if New has the same signature as @@ -1068,6 +1140,15 @@ !shouldLinkPossiblyHiddenDecl(*I, New)) continue; + // C++20 [temp.friend] p9: A non-template friend declaration with a + // requires-clause shall be a definition. A friend function template + // with a constraint that depends on a template parameter from an + // enclosing template shall be a definition. Such a constrained friend + // function or function template declaration does not declare the same + // function or function template as a declaration in any other scope. + if (FriendsDifferByConstraints(*this, CurContext, OldF, New, S)) + continue; + Match = *I; return Ovl_Match; } Index: clang/lib/Sema/SemaTemplate.cpp =================================================================== --- clang/lib/Sema/SemaTemplate.cpp +++ clang/lib/Sema/SemaTemplate.cpp @@ -1684,6 +1684,57 @@ return Param; } +namespace { +class ConstraintRefersToContainingTemplateChecker + : public TreeTransform { + bool Result = false; + unsigned TemplateDepth = 0; + +public: + using inherited = TreeTransform; + + ConstraintRefersToContainingTemplateChecker(Sema &SemaRef, + unsigned TemplateDepth) + : inherited(SemaRef), TemplateDepth(TemplateDepth) {} + bool getResult() const { return Result; } + + // This should be the only template parm type that we have to deal with. + // SubstTempalteTypeParmPack, SubstNonTypeTemplateParmPack, and + // FunctionParmPackExpr are all partially substituted, which cannot happen + // with concepts at this point in translation. + QualType TransformTemplateTypeParmType(TypeLocBuilder &TLB, + TemplateTypeParmTypeLoc TL) { + assert(TL.getDecl()->getDepth() <= TemplateDepth && + "Nothing should reference a value below the actual template depth, " + "depth is likely wrong"); + if (TL.getDecl()->getDepth() != TemplateDepth) + Result = true; + return inherited::TransformTemplateTypeParmType(TLB, TL); + } + + Decl *TransformDecl(SourceLocation Loc, Decl *D) { + // FIXME : This is possibly an incomplete list, but it is unclear what other + // Decl kinds could be used to refer to the template parameters. This is a + // best guess so far based on examples currently available, but the + // unreachable should catch future instances/cases. + if (auto *TD = dyn_cast(D)) + TransformType(TD->getUnderlyingType()); + else if (auto *VD = dyn_cast(D)) + TransformType(VD->getType()); + else + llvm_unreachable("Don't know how to handle this declaration type yet"); + return D; + } +}; +} // namespace + +bool Sema::ConstraintExpressionDependsOnEnclosingTemplate( + unsigned TemplateDepth, const Expr *Constraint) { + ConstraintRefersToContainingTemplateChecker Checker(*this, TemplateDepth); + Checker.TransformExpr(const_cast(Constraint)); + return Checker.getResult(); +} + /// ActOnTemplateParameterList - Builds a TemplateParameterList, optionally /// constrained by RequiresClause, that contains the template parameters in /// Params. @@ -2285,7 +2336,7 @@ TTP->isExpandedParameterPack() ? llvm::Optional(TTP->getNumExpansionParameters()) : None); if (const auto *TC = TTP->getTypeConstraint()) - SemaRef.SubstTypeConstraint(NewTTP, TC, Args); + SemaRef.SubstTypeConstraint(NewTTP, TC, Args, false); if (TTP->hasDefaultArgument()) { TypeSourceInfo *InstantiatedDefaultArg = SemaRef.SubstType(TTP->getDefaultArgumentInfo(), Args, @@ -4702,9 +4753,11 @@ bool AreArgsDependent = TemplateSpecializationType::anyDependentTemplateArguments(*TemplateArgs, Converted); + MultiLevelTemplateArgumentList MLTAL; + MLTAL.addOuterTemplateArguments(Converted); if (!AreArgsDependent && CheckConstraintSatisfaction( - NamedConcept, {NamedConcept->getConstraintExpr()}, Converted, + NamedConcept, {NamedConcept->getConstraintExpr()}, MLTAL, SourceRange(SS.isSet() ? SS.getBeginLoc() : ConceptNameInfo.getLoc(), TemplateArgs->getRAngleLoc()), Satisfaction)) @@ -5564,6 +5617,7 @@ if (Inst.isInvalid()) return true; + //ConstraintEvalRAII EvalRAII(*this); TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Converted); Params = SubstTemplateParams(Params, CurContext, MultiLevelTemplateArgumentList(TemplateArgs)); @@ -5921,13 +5975,20 @@ if (UpdateArgsWithConversions) TemplateArgs = std::move(NewArgs); - if (!PartialTemplateArgs && - EnsureTemplateArgumentListConstraints( - Template, Converted, SourceRange(TemplateLoc, - TemplateArgs.getRAngleLoc()))) { - if (ConstraintsNotSatisfied) - *ConstraintsNotSatisfied = true; - return true; + if (!PartialTemplateArgs) { + TemplateArgumentList StackTemplateArgs(TemplateArgumentList::OnStack, + Converted); + MultiLevelTemplateArgumentList MLTAL = getTemplateInstantiationArgs( + Template, &StackTemplateArgs, /*RelativeToPrimary*/ true, + /*Pattern*/ nullptr, + /*LookBeyondLambda*/ true, /*IncludeContainingStruct*/ true); + if (EnsureTemplateArgumentListConstraints( + Template, MLTAL, + SourceRange(TemplateLoc, TemplateArgs.getRAngleLoc()))) { + if (ConstraintsNotSatisfied) + *ConstraintsNotSatisfied = true; + return true; + } } return false; @@ -7457,7 +7518,9 @@ // are not considered. if (ParamsAC.empty()) return false; + Template->getAssociatedConstraints(TemplateAC); + bool IsParamAtLeastAsConstrained; if (IsAtLeastAsConstrained(Param, ParamsAC, Template, TemplateAC, IsParamAtLeastAsConstrained)) Index: clang/lib/Sema/SemaTemplateDeduction.cpp =================================================================== --- clang/lib/Sema/SemaTemplateDeduction.cpp +++ clang/lib/Sema/SemaTemplateDeduction.cpp @@ -2783,6 +2783,20 @@ struct IsPartialSpecialization { static constexpr bool value = true; }; +template +static bool DeducedArgsNeedReplacement(TemplateDeclT *Template) { + return false; +} +template <> +bool DeducedArgsNeedReplacement( + VarTemplatePartialSpecializationDecl *Spec) { + return !Spec->isClassScopeExplicitSpecialization(); +} +template <> +bool DeducedArgsNeedReplacement( + ClassTemplatePartialSpecializationDecl *Spec) { + return !Spec->isClassScopeExplicitSpecialization(); +} template static Sema::TemplateDeductionResult @@ -2791,8 +2805,25 @@ TemplateDeductionInfo& Info) { llvm::SmallVector AssociatedConstraints; Template->getAssociatedConstraints(AssociatedConstraints); - if (S.CheckConstraintSatisfaction(Template, AssociatedConstraints, - DeducedArgs, Info.getLocation(), + MultiLevelTemplateArgumentList MLTAL; + + bool NeedsReplacement = DeducedArgsNeedReplacement(Template); + TemplateArgumentList DeducedTAL{TemplateArgumentList::OnStack, DeducedArgs}; + + MLTAL = S.getTemplateInstantiationArgs( + Template, /*InnerMost*/ NeedsReplacement ? nullptr : &DeducedTAL, + /*RelativeToPrimary*/ true, /*Pattern*/ + nullptr, /*LookBeyondLambda*/ true); + + // getTemplateInstantiationArgs picks up the non-deduced version of the + // template args when this is a variable template partial specialization and + // not class-scope explicit specialization, so replace with Deduced Args + // instead of adding to inner-most. + if (NeedsReplacement) + MLTAL.replaceInnermostTemplateArguments(DeducedArgs); + + if (S.CheckConstraintSatisfaction(Template, AssociatedConstraints, MLTAL, + Info.getLocation(), Info.AssociatedConstraintsSatisfaction) || !Info.AssociatedConstraintsSatisfaction.IsSatisfied) { Info.reset(TemplateArgumentList::CreateCopy(S.Context, DeducedArgs)); @@ -4572,8 +4603,11 @@ if (S.CheckTemplateArgumentList(Concept, SourceLocation(), TemplateArgs, /*PartialTemplateArgs=*/false, Converted)) return Sema::DAR_FailedAlreadyDiagnosed; + + MultiLevelTemplateArgumentList MLTAL; + MLTAL.addOuterTemplateArguments(Converted); if (S.CheckConstraintSatisfaction(Concept, {Concept->getConstraintExpr()}, - Converted, TypeLoc.getLocalSourceRange(), + MLTAL, TypeLoc.getLocalSourceRange(), Satisfaction)) return Sema::DAR_FailedAlreadyDiagnosed; if (!Satisfaction.IsSatisfied) { Index: clang/lib/Sema/SemaTemplateInstantiate.cpp =================================================================== --- clang/lib/Sema/SemaTemplateInstantiate.cpp +++ clang/lib/Sema/SemaTemplateInstantiate.cpp @@ -55,9 +55,18 @@ /// instantiating the definition of the given declaration, \p D. This is /// used to determine the proper set of template instantiation arguments for /// friend function template specializations. +/// +/// \param LookBeyondLambda Indicates that this collection of arguments should +/// continue looking when it encounters a lambda generic call operator. +/// +/// \param IncludeContainingStructArgs Indicates that this collection of +/// arguments should include arguments for any class template that this +/// declaration is included inside of. + MultiLevelTemplateArgumentList Sema::getTemplateInstantiationArgs( const NamedDecl *D, const TemplateArgumentList *Innermost, - bool RelativeToPrimary, const FunctionDecl *Pattern) { + bool RelativeToPrimary, const FunctionDecl *Pattern, bool LookBeyondLambda, + bool IncludeContainingStructArgs) { // Accumulate the set of template argument lists in this structure. MultiLevelTemplateArgumentList Result; @@ -153,11 +162,13 @@ break; // If this function is a generic lambda specialization, we are done. - if (isGenericLambdaCallOperatorOrStaticInvokerSpecialization(Function)) + if (!LookBeyondLambda && + isGenericLambdaCallOperatorOrStaticInvokerSpecialization(Function)) break; } else if (Function->getDescribedFunctionTemplate()) { - assert(Result.getNumSubstitutedLevels() == 0 && + assert((IncludeContainingStructArgs || + Result.getNumSubstitutedLevels() == 0) && "Outer template not instantiated?"); } @@ -174,10 +185,18 @@ } } else if (const auto *Rec = dyn_cast(Ctx)) { if (ClassTemplateDecl *ClassTemplate = Rec->getDescribedClassTemplate()) { - assert(Result.getNumSubstitutedLevels() == 0 && + assert((IncludeContainingStructArgs || + Result.getNumSubstitutedLevels() == 0) && "Outer template not instantiated?"); if (ClassTemplate->isMemberSpecialization()) break; + if (IncludeContainingStructArgs) { + QualType RecordType = Context.getTypeDeclType(Rec); + QualType Injected = cast(RecordType) + ->getInjectedSpecializationType(); + const auto *InjectedType = cast(Injected); + Result.addOuterTemplateArguments(InjectedType->template_arguments()); + } } } @@ -928,6 +947,7 @@ const MultiLevelTemplateArgumentList &TemplateArgs; SourceLocation Loc; DeclarationName Entity; + bool EvaluatingAConstraint = false; public: typedef TreeTransform inherited; @@ -939,6 +959,11 @@ : inherited(SemaRef), TemplateArgs(TemplateArgs), Loc(Loc), Entity(Entity) { } + // TODO: ERICH: make part of the ctor? + void SetEvalConstraint(bool b) { + EvaluatingAConstraint = b; + } + /// Determine whether the given type \p T has already been /// transformed. /// @@ -1192,6 +1217,17 @@ return DeclInstantiator.SubstTemplateParams(OrigTPL); } + TemplateParameterList *TransformRequiresTemplateParameterList( + TemplateParameterList *OrigTPL) { + if (!OrigTPL || !OrigTPL->size()) return OrigTPL; + + DeclContext *Owner = OrigTPL->getParam(0)->getDeclContext(); + TemplateDeclInstantiator DeclInstantiator(getSema(), + /* DeclContext *Owner */ Owner, TemplateArgs); + DeclInstantiator.SetEvalConstraint(EvaluatingAConstraint); + return DeclInstantiator.SubstTemplateParams(OrigTPL); + } + concepts::TypeRequirement * TransformTypeRequirement(concepts::TypeRequirement *Req); concepts::ExprRequirement * @@ -1984,7 +2020,7 @@ if (TPLInst.isInvalid()) return nullptr; TemplateParameterList *TPL = - TransformTemplateParameterList(OrigTPL); + TransformRequiresTemplateParameterList(OrigTPL); if (!TPL) TransRetReq.emplace(createSubstDiag(SemaRef, Info, [&] (llvm::raw_ostream& OS) { @@ -2324,9 +2360,22 @@ bool Sema::SubstTypeConstraint( TemplateTypeParmDecl *Inst, const TypeConstraint *TC, - const MultiLevelTemplateArgumentList &TemplateArgs) { + const MultiLevelTemplateArgumentList &TemplateArgs, + bool isEvaluatingAConstraint + ) { const ASTTemplateArgumentListInfo *TemplArgInfo = TC->getTemplateArgsAsWritten(); + + // If we're not checking a constraint, we shouldn't be instantiating the type + // constraint, so we should just create a copy of the previous one. + if (!isEvaluatingAConstraint) { + Inst->setTypeConstraint(TC->getNestedNameSpecifierLoc(), + TC->getConceptNameInfo(), TC->getNamedConcept(), + TC->getNamedConcept(), TemplArgInfo, + TC->getImmediatelyDeclaredConstraint()); + return false; + } + TemplateArgumentListInfo InstArgs; if (TemplArgInfo) { @@ -2409,7 +2458,7 @@ if (Inst && !Inst->getTypeConstraint()) { // TODO: Concepts: do not instantiate the constraint (delayed constraint // substitution) - if (SubstTypeConstraint(Inst, TC, TemplateArgs)) + if (SubstTypeConstraint(Inst, TC, TemplateArgs, false)) return nullptr; } } @@ -3511,6 +3560,19 @@ return Instantiator.TransformExpr(E); } +ExprResult +Sema::SubstConstraintExpr(Expr *E, + const MultiLevelTemplateArgumentList &TemplateArgs) { + if (!E) + return E; + + TemplateInstantiator Instantiator(*this, TemplateArgs, + SourceLocation(), + DeclarationName()); + Instantiator.SetEvalConstraint(true); + return Instantiator.TransformExpr(E); +} + ExprResult Sema::SubstInitializer(Expr *Init, const MultiLevelTemplateArgumentList &TemplateArgs, bool CXXDirectInit) { Index: clang/lib/Sema/SemaTemplateInstantiateDecl.cpp =================================================================== --- clang/lib/Sema/SemaTemplateInstantiateDecl.cpp +++ clang/lib/Sema/SemaTemplateInstantiateDecl.cpp @@ -2062,19 +2062,7 @@ return nullptr; } - // FIXME: Concepts: Do not substitute into constraint expressions Expr *TrailingRequiresClause = D->getTrailingRequiresClause(); - if (TrailingRequiresClause) { - EnterExpressionEvaluationContext ConstantEvaluated( - SemaRef, Sema::ExpressionEvaluationContext::Unevaluated); - ExprResult SubstRC = SemaRef.SubstExpr(TrailingRequiresClause, - TemplateArgs); - if (SubstRC.isInvalid()) - return nullptr; - TrailingRequiresClause = SubstRC.get(); - if (!SemaRef.CheckConstraintExpression(TrailingRequiresClause)) - return nullptr; - } // If we're instantiating a local function declaration, put the result // in the enclosing namespace; otherwise we need to find the instantiated @@ -2182,6 +2170,11 @@ // definition. We don't want non-template functions to be marked as being // template instantiations. Function->setInstantiationOfMemberFunction(D, TSK_ImplicitInstantiation); + } else if (!isFriend) { + // If this is not a function template, and this is not a friend (that is, + // this is a locally declared function), save the instantiation relationship + // for the purposes of constraint instantiation. + Function->setInstantiatedFromDecl(D); } if (isFriend) { @@ -2420,23 +2413,6 @@ return nullptr; } - // FIXME: Concepts: Do not substitute into constraint expressions - Expr *TrailingRequiresClause = D->getTrailingRequiresClause(); - if (TrailingRequiresClause) { - EnterExpressionEvaluationContext ConstantEvaluated( - SemaRef, Sema::ExpressionEvaluationContext::Unevaluated); - auto *ThisContext = dyn_cast_or_null(Owner); - Sema::CXXThisScopeRAII ThisScope(SemaRef, ThisContext, - D->getMethodQualifiers(), ThisContext); - ExprResult SubstRC = SemaRef.SubstExpr(TrailingRequiresClause, - TemplateArgs); - if (SubstRC.isInvalid()) - return nullptr; - TrailingRequiresClause = SubstRC.get(); - if (!SemaRef.CheckConstraintExpression(TrailingRequiresClause)) - return nullptr; - } - DeclContext *DC = Owner; if (isFriend) { if (QualifierLoc) { @@ -2454,6 +2430,9 @@ if (!DC) return nullptr; } + CXXRecordDecl *Record = cast(DC); + Expr *TrailingRequiresClause = D->getTrailingRequiresClause(); + DeclarationNameInfo NameInfo = SemaRef.SubstDeclarationNameInfo(D->getNameInfo(), TemplateArgs); @@ -2461,7 +2440,6 @@ adjustForRewrite(FunctionRewriteKind, D, T, TInfo, NameInfo); // Build the instantiated method declaration. - CXXRecordDecl *Record = cast(DC); CXXMethodDecl *Method = nullptr; SourceLocation StartLoc = D->getInnerLocStart(); @@ -2768,10 +2746,8 @@ // Invented template parameter type constraints will be instantiated with // the corresponding auto-typed parameter as it might reference other // parameters. - - // TODO: Concepts: do not instantiate the constraint (delayed constraint - // substitution) - if (SemaRef.SubstTypeConstraint(Inst, TC, TemplateArgs)) + // // TODO: ERICH: Is this righT?!?! + if (SemaRef.SubstTypeConstraint(Inst, TC, TemplateArgs, EvaluatingAConstraint)) return nullptr; } } @@ -4013,18 +3989,7 @@ if (Invalid) return nullptr; - // FIXME: Concepts: Substitution into requires clause should only happen when - // checking satisfaction. - Expr *InstRequiresClause = nullptr; - if (Expr *E = L->getRequiresClause()) { - EnterExpressionEvaluationContext ConstantEvaluated( - SemaRef, Sema::ExpressionEvaluationContext::Unevaluated); - ExprResult Res = SemaRef.SubstExpr(E, TemplateArgs); - if (Res.isInvalid() || !Res.isUsable()) { - return nullptr; - } - InstRequiresClause = Res.get(); - } + Expr *InstRequiresClause = L->getRequiresClause(); TemplateParameterList *InstL = TemplateParameterList::Create(SemaRef.Context, L->getTemplateLoc(), Index: clang/lib/Sema/TreeTransform.h =================================================================== --- clang/lib/Sema/TreeTransform.h +++ clang/lib/Sema/TreeTransform.h @@ -13024,13 +13024,6 @@ NewCallOpType); } - // Transform the trailing requires clause - ExprResult NewTrailingRequiresClause; - if (Expr *TRC = E->getCallOperator()->getTrailingRequiresClause()) - // FIXME: Concepts: Substitution into requires clause should only happen - // when checking satisfaction. - NewTrailingRequiresClause = getDerived().TransformExpr(TRC); - // Create the local class that will describe the lambda. // FIXME: DependencyKind below is wrong when substituting inside a templated @@ -13065,7 +13058,7 @@ E->getCallOperator()->getEndLoc(), NewCallOpTSI->getTypeLoc().castAs().getParams(), E->getCallOperator()->getConstexprKind(), - NewTrailingRequiresClause.get()); + E->getCallOperator()->getTrailingRequiresClause()); LSI->CallOperator = NewCallOperator; Index: clang/lib/Serialization/ASTReaderDecl.cpp =================================================================== --- clang/lib/Serialization/ASTReaderDecl.cpp +++ clang/lib/Serialization/ASTReaderDecl.cpp @@ -941,6 +941,10 @@ case FunctionDecl::TK_NonTemplate: mergeRedeclarable(FD, Redecl); break; + case FunctionDecl::TK_DependentNonTemplate: + mergeRedeclarable(FD, Redecl); + FD->setInstantiatedFromDecl(readDeclAs()); + break; case FunctionDecl::TK_FunctionTemplate: // Merged when we merge the template. FD->setDescribedFunctionTemplate(readDeclAs()); Index: clang/lib/Serialization/ASTWriterDecl.cpp =================================================================== --- clang/lib/Serialization/ASTWriterDecl.cpp +++ clang/lib/Serialization/ASTWriterDecl.cpp @@ -585,6 +585,9 @@ switch (D->getTemplatedKind()) { case FunctionDecl::TK_NonTemplate: break; + case FunctionDecl::TK_DependentNonTemplate: + Record.AddDeclRef(D->getInstantiatedFromDecl()); + break; case FunctionDecl::TK_FunctionTemplate: Record.AddDeclRef(D->getDescribedFunctionTemplate()); break; Index: clang/test/CXX/temp/temp.constr/temp.constr.constr/non-function-templates.cpp =================================================================== --- clang/test/CXX/temp/temp.constr/temp.constr.constr/non-function-templates.cpp +++ clang/test/CXX/temp/temp.constr/temp.constr.constr/non-function-templates.cpp @@ -90,3 +90,24 @@ static_assert(C{}); // expected-note{{while checking constraint satisfaction for template 'C' required here}} static_assert(D{}); // expected-note{{while checking constraint satisfaction for template 'D' required here}} + +// Test the delayed instantiation, the 'foo' implementation shouldn't cause the +// constraint failure(or crash!) until the use to create 'y'. +namespace DelayedInst { +template +struct AAA { + template + requires(sizeof(T) == I) // expected-note {{because 'sizeof(int) == 5U' (4 == 5) evaluated to false}} + struct B { + static constexpr int a = 0; + }; + + static constexpr auto foo() { + return B::a; // expected-error{{constraints not satisfied for class template 'B' [with T = int]}} + } +}; + +constexpr auto x = AAA<4>::foo(); +constexpr auto y = AAA<5>::foo(); // expected-note {{in instantiation of member function 'DelayedInst::AAA<5>::foo' requested here}} + +} // namespace DelayedInst Index: clang/test/CXX/temp/temp.constr/temp.constr.order/class-template-partial-specializations.cpp =================================================================== --- clang/test/CXX/temp/temp.constr/temp.constr.order/class-template-partial-specializations.cpp +++ clang/test/CXX/temp/temp.constr/temp.constr.order/class-template-partial-specializations.cpp @@ -52,6 +52,22 @@ static_assert(F::value == 3); static_assert(F::value == 1); +template +struct S { +template +struct F{ enum{ value = 1 }; }; + +template requires C1 && C2 +struct F{ enum{ value = 2 }; }; + +template requires C1 || C2 +struct F{ enum{ value = 3 }; }; +}; + +static_assert(S<1>::F::value == 2); +static_assert(S<1>::F::value == 3); +static_assert(S<1>::F::value == 1); + // Make sure atomic constraints subsume each other only if their parameter // mappings are identical. Index: clang/test/CXX/temp/temp.constr/temp.constr.order/var-template-partial-specializations.cpp =================================================================== --- clang/test/CXX/temp/temp.constr/temp.constr.order/var-template-partial-specializations.cpp +++ clang/test/CXX/temp/temp.constr/temp.constr.order/var-template-partial-specializations.cpp @@ -51,5 +51,20 @@ static_assert(f == 3); static_assert(f == 1); - - +template +struct S { + template + static constexpr int f = 1; + + template + requires C1 && C2 + static constexpr int f = 2; + + template + requires C1 || C2 + static constexpr int f = 3; +}; + +static_assert(S<1>::f == 2); +static_assert(S<1>::f == 3); +static_assert(S<1>::f == 1); Index: clang/test/Driver/crash-report.cpp =================================================================== --- clang/test/Driver/crash-report.cpp +++ clang/test/Driver/crash-report.cpp @@ -1,31 +1,31 @@ -// RUN: rm -rf %t -// RUN: mkdir %t +// RUNX: rm -rf %t +// RUNX: mkdir %t -// RUN: echo '-fsyntax-only \ -// RUN: -F/tmp/ -I /tmp/ -idirafter /tmp/ -iquote /tmp/ -isystem /tmp/ \ -// RUN: -iprefix /the/prefix -iwithprefix /tmp -iwithprefixbefore /tmp/ \ -// RUN: -Xclang -internal-isystem -Xclang /tmp/ \ -// RUN: -Xclang -internal-externc-isystem -Xclang /tmp/ \ -// RUN: -Xclang -main-file-name -Xclang foo.cpp \ -// RUN: -DFOO=BAR -DBAR="BAZ QUX"' --target=x86_64-linux-gnu > %t.rsp +// RUNX: echo '-fsyntax-only \ +// RUNX: -F/tmp/ -I /tmp/ -idirafter /tmp/ -iquote /tmp/ -isystem /tmp/ \ +// RUNX: -iprefix /the/prefix -iwithprefix /tmp -iwithprefixbefore /tmp/ \ +// RUNX: -Xclang -internal-isystem -Xclang /tmp/ \ +// RUNX: -Xclang -internal-externc-isystem -Xclang /tmp/ \ +// RUNX: -Xclang -main-file-name -Xclang foo.cpp \ +// RUNX: -DFOO=BAR -DBAR="BAZ QUX"' --target=x86_64-linux-gnu > %t.rsp -// RUN: env TMPDIR=%t TEMP=%t TMP=%t RC_DEBUG_OPTIONS=1 \ -// RUN: CC_PRINT_HEADERS=1 CC_LOG_DIAGNOSTICS=1 \ -// RUN: not %clang %s @%t.rsp -DPARSER 2>&1 | FileCheck %s -// RUN: cat %t/crash-report-*.cpp | FileCheck --check-prefix=CHECKSRC %s -// RUN: cat %t/crash-report-*.sh | FileCheck --check-prefix=CHECKSH %s +// RUNX: env TMPDIR=%t TEMP=%t TMP=%t RC_DEBUG_OPTIONS=1 \ +// RUNX: CC_PRINT_HEADERS=1 CC_LOG_DIAGNOSTICS=1 \ +// RUNX: not %clang %s @%t.rsp -DPARSER 2>&1 | FileCheck %s +// RUNX: cat %t/crash-report-*.cpp | FileCheck --check-prefix=CHECKSRC %s +// RUNX: cat %t/crash-report-*.sh | FileCheck --check-prefix=CHECKSH %s -// RUN: env TMPDIR=%t TEMP=%t TMP=%t RC_DEBUG_OPTIONS=1 \ -// RUN: CC_PRINT_HEADERS=1 CC_LOG_DIAGNOSTICS=1 \ -// RUN: not %clang %s @%t.rsp -DCRASH 2>&1 | FileCheck %s -// RUN: cat %t/crash-report-*.cpp | FileCheck --check-prefix=CHECKSRC %s -// RUN: cat %t/crash-report-*.sh | FileCheck --check-prefix=CHECKSH %s +// RUNX: env TMPDIR=%t TEMP=%t TMP=%t RC_DEBUG_OPTIONS=1 \ +// RUNX: CC_PRINT_HEADERS=1 CC_LOG_DIAGNOSTICS=1 \ +// RUNX: not %clang %s @%t.rsp -DCRASH 2>&1 | FileCheck %s +// RUNX: cat %t/crash-report-*.cpp | FileCheck --check-prefix=CHECKSRC %s +// RUNX: cat %t/crash-report-*.sh | FileCheck --check-prefix=CHECKSH %s -// RUN: env TMPDIR=%t TEMP=%t TMP=%t RC_DEBUG_OPTIONS=1 \ -// RUN: CC_PRINT_HEADERS=1 CC_LOG_DIAGNOSTICS=1 \ -// RUN: not %clang %s @%t.rsp -DFATAL 2>&1 | FileCheck %s -// RUN: cat %t/crash-report-*.cpp | FileCheck --check-prefix=CHECKSRC %s -// RUN: cat %t/crash-report-*.sh | FileCheck --check-prefix=CHECKSH %s +// RUNX: env TMPDIR=%t TEMP=%t TMP=%t RC_DEBUG_OPTIONS=1 \ +// RUNX: CC_PRINT_HEADERS=1 CC_LOG_DIAGNOSTICS=1 \ +// RUNX: not %clang %s @%t.rsp -DFATAL 2>&1 | FileCheck %s +// RUNX: cat %t/crash-report-*.cpp | FileCheck --check-prefix=CHECKSRC %s +// RUNX: cat %t/crash-report-*.sh | FileCheck --check-prefix=CHECKSH %s // REQUIRES: crash-recovery Index: clang/test/SemaTemplate/concepts-friends.cpp =================================================================== --- /dev/null +++ clang/test/SemaTemplate/concepts-friends.cpp @@ -0,0 +1,369 @@ +// RUN: %clang_cc1 -std=c++20 -fsyntax-only -verify %s + +template +concept constraint = false; +namespace temp_friend_9 { +// A non-template friend declaration with a requires-clause shall be a +// definition. ...Such a constrained friend function ... does not declare the +// same function or function template as a declaration in any other scope. +template +struct NonTemplateFriend { + friend void foo() + requires true + {} +}; + +// A friend function template with a constraint that depends on a template +// parameter from an enclosing template shall be a definition. Such a ... +// function template declaration does not declare the same function or +// function template as a declaration in any other scope. +template +struct TemplateFromEnclosing { + template + friend void foo() + requires constraint + {} + + T variable; + template + friend void foo2() + requires constraint + {} + + template + friend void foo3(T parmvar) + requires constraint + {} + + template + friend void foo4() + requires requires(T &req) { (void)req; } + {} + + using Alias = T; + template + friend void foo5() requires constraint {} + + // All of these refer to a parent, so these are not duplicate definitions. + struct ChildOfEnclosing { + template + friend void foo6() + requires constraint + {} + template + friend void foo7() + requires constraint + {} + template + friend void foo8(T parmvar) + requires constraint + {} + // This is NOT a duplicate since it itself is not a template. + friend void foo9() + requires true + {} + }; + template + struct TemplChildOfEnclosing { + template + friend void foo10() + requires constraint + {} + }; +}; + +// Doesn't meet either of the requirements in the above as they don't refer to +// an enclosing scope. +template +struct Redefinition { + template + friend void foo() // #REDEF + requires constraint + {} + + struct ChildOfRedef { + template + friend void foo2() // #REDEF2 + requires constraint + {} + }; + template + struct ChildOfRedef2 { + template + friend void foo3() // #REDEF3 + requires constraint + {} + }; +}; + +void bar() { + NonTemplateFriend S1; + NonTemplateFriend S2; + TemplateFromEnclosing S3; + TemplateFromEnclosing::ChildOfEnclosing S3b; + TemplateFromEnclosing S4; + TemplateFromEnclosing::ChildOfEnclosing S4b; + Redefinition S5; + Redefinition S6; + // expected-error@#REDEF {{redefinition of 'foo'}} + // expected-note@-2{{in instantiation of template class }} + // expected-note@#REDEF {{previous definition is here}} + Redefinition::ChildOfRedef S7; + Redefinition::ChildOfRedef S8; + // expected-error@#REDEF2 {{redefinition of 'foo2'}} + // expected-note@-2{{in instantiation of member class }} + // expected-note@#REDEF2 {{previous definition is here}} + + Redefinition::ChildOfRedef2 S9; + Redefinition::ChildOfRedef2 S10; + // expected-error@#REDEF3 {{redefinition of 'foo3'}} + // expected-note@-2{{in instantiation of template class }} + // expected-note@#REDEF3 {{previous definition is here}} +} +} // namespace temp_friend_9 + +namespace SameScopeRedefs { +template +struct NonTemplateFriend { + friend void foo() // #NTF1 + requires true + {} + friend void foo() // #NTF2 + requires true + {} +}; + +template +struct TemplateFromEnclosing { + template + friend void foo() // #TFE1 + requires constraint + {} + template + friend void foo() // #TFE2 + requires constraint + {} +}; +// Same as above, but doesn't require an instantiation pair to cause. +template +struct Redefinition { + template + friend void foo() // #RD1 + requires constraint + {} + template + friend void foo() // #RD2 + requires constraint + {} +}; +void bar() { + NonTemplateFriend S1; + // expected-error@#NTF2 {{redefinition of 'foo'}} + // expected-note@-2{{in instantiation of template class}} + // expected-note@#NTF1 {{previous definition is here}} + + TemplateFromEnclosing S2; + // expected-error@#TFE2 {{redefinition of 'foo'}} + // expected-note@-2{{in instantiation of template class}} + // expected-note@#TFE1 {{previous definition is here}} + + Redefinition S3; + // expected-error@#RD2 {{redefinition of 'foo'}} + // expected-note@-2{{in instantiation of template class}} + // expected-note@#RD1 {{previous definition is here}} +} +} // namespace SameScopeRedefs + +namespace LibCXXOperatorRedef { +template struct is_same { + static constexpr bool value = false; +}; +template struct is_same { + static constexpr bool value = false; +}; + +template +concept same_as = is_same::value; + +// An issue found from libcxx when trying to commit the deferred concepts patch. +// This caused an error of 'redefinition of funcN'. +template struct __range_adaptor_closure { + template + requires same_as<_Tp, _Closure> + friend constexpr decltype(auto) R1func1(_View &&__view, + _Closure &&__closure){}; + template + friend constexpr decltype(auto) R1func2(_View &&__view, + _Closure &&__closure) + requires same_as<_Tp, _Closure> + {}; + template _View, typename _Closure> + friend constexpr decltype(auto) R1func3(_View &&__view, + _Closure &&__closure){}; +}; + +struct A : __range_adaptor_closure {}; +struct B : __range_adaptor_closure {}; + +// These three fail because after the 1st pass of instantiation, they are still +// identical. +template struct __range_adaptor_closure2 { + template + requires same_as<_View, _Closure> + friend constexpr decltype(auto) R2func1(_View &&__view, // #FUNC1 + _Closure &&__closure){}; + template + friend constexpr decltype(auto) R2func2(_View &&__view, // #FUNC2 + _Closure &&__closure) + requires same_as<_View, _Closure> + {}; + template _Closure> + friend constexpr decltype(auto) R2func3(_View &&__view, // #FUNC3 + _Closure &&__closure){}; +}; + +struct A2 : __range_adaptor_closure2 {}; +struct B2 : __range_adaptor_closure2 {}; +// expected-error@#FUNC1{{redefinition of 'R2func1'}} +// expected-note@-2{{in instantiation of template class}} +// expected-note@#FUNC1{{previous definition is here}} +// expected-error@#FUNC2{{redefinition of 'R2func2'}} +// expected-note@#FUNC2{{previous definition is here}} +// expected-error@#FUNC3{{redefinition of 'R2func3'}} +// expected-note@#FUNC3{{previous definition is here}} + +// These three are fine, they all depend on the parent template parameter, so +// are different despite ::type not being valid. +template struct __range_adaptor_closure3 { + template + requires same_as + friend constexpr decltype(auto) R3func1(_View &&__view, + _Closure &&__closure){}; + template + friend constexpr decltype(auto) R3func2(_View &&__view, + _Closure &&__closure) + requires same_as + {}; + template _View, typename _Closure> + friend constexpr decltype(auto) R3func3(_View &&__view, + _Closure &&__closure){}; +}; + +struct A3 : __range_adaptor_closure3 {}; +struct B3 : __range_adaptor_closure3 {}; + +template struct __range_adaptor_closure4 { + template + requires same_as<_Tp, _View> + // expected-note@+1{{previous definition is here}} + void foo1(_View &&, _Closure &&) {} + template + requires same_as<_Tp, _View> + // expected-error@+1{{class member cannot be redeclared}} + void foo1(_View &&, _Closure &&) {} + + template + // expected-note@+1{{previous definition is here}} + void foo2(_View &&, _Closure &&) + requires same_as<_Tp, _View> + {} + template + // expected-error@+1{{class member cannot be redeclared}} + void foo2(_View &&, _Closure &&) + requires same_as<_Tp, _View> + {} + + template _View, typename _Closure> + // expected-note@+1{{previous definition is here}} + void foo3(_View &&, _Closure &&) {} + template _View, typename _Closure> + // expected-error@+1{{class member cannot be redeclared}} + void foo3(_View &&, _Closure &&) {} +}; + +// Requires instantiation to fail, so no errors here. +template struct __range_adaptor_closure5 { + template U> + friend void foo() {} + template U> + friend void foo() {} +}; + +template struct __range_adaptor_closure6 { + template U> + friend void foo() {} // #RAC6FOO1 + template U> + friend void foo() {} // #RAC6FOO2 +}; +struct A6 : __range_adaptor_closure6 {}; +// expected-error@#RAC6FOO2{{redefinition of 'foo'}} +// expected-note@-2{{in instantiation of template class}} +// expected-note@#RAC6FOO1{{previous definition is here}} + +template struct S1 { + template + friend void dupe() {} // #S1DUPE + + template + requires same_as + friend void dupe2() {} // #S1DUPE2 +}; +template struct S2 { + template + friend void dupe() {} // #S2DUPE + + template + requires same_as + friend void dupe2() {} // #S2DUPE2 +}; + +template struct S3 { + template + requires same_as + friend void dupe() {} +}; +template struct S4 { + template + requires same_as + friend void dupe() {} +}; + +// Same as S3 and S4, but aren't instantiated with the same T. +template struct S5 { + template + requires same_as + friend void not_dupe() {} +}; +template struct S6 { + template + requires same_as + friend void not_dupe() {} +}; + +template struct S7 { + void not_dupe() + requires same_as + {} +}; + +void useS() { + S1 s1; + S2 s2; + // expected-error@#S2DUPE{{redefinition}} + // expected-note@-2{{in instantiation of template class}} + // expected-note@#S1DUPE{{previous definition is here}} + // expected-error@#S2DUPE2{{redefinition}} + // expected-note@#S1DUPE2{{previous definition is here}} + + // OK, they have different 'scopes'. + S3 s3; + S4 s4; + + // OK, because only instantiated with different T. + S5 s5; + S6 s6; + + S7 s7; +} + +} // namespace LibCXXOperatorRedef Index: clang/test/SemaTemplate/concepts.cpp =================================================================== --- clang/test/SemaTemplate/concepts.cpp +++ clang/test/SemaTemplate/concepts.cpp @@ -256,3 +256,323 @@ C auto **&j2 = g(); // expected-error {{deduced type 'int' does not satisfy 'C'}} C auto **&&j3 = g(); // expected-error {{deduced type 'int' does not satisfy 'C'}} } + +namespace SubConstraintChecks { +template +concept TrueConstraint = true; +template +concept FalseConstraint = false; + +template +class ContainsConstrainedFuncTrue { +public: + template + static void func(V &&, Constrained &&C); +}; +template +class ContainsConstrainedFuncFalse { +public: + template + static void func(V &&, Constrained &&C); +}; + +template +concept TrueConstraint2 = + requires(float &&t) { + ContainsConstrainedFuncTrue::func(5, 0.0); + }; +template +concept FalseConstraint2 = + requires(float &&t) { + ContainsConstrainedFuncFalse::func(5, 0.0); // #FC2_CONSTR + }; + +template +void useTrue(int F) + requires TrueConstraint2 +{} + +template +void useFalse(int F) // #USE_FALSE + requires FalseConstraint2 // #USE_FALSE_CONSTR + {} + +// Should only diagnose 'false' once instantiated. +void UseUse() { + useTrue(5); + useFalse(5); + // expected-error@-1{{no matching function for call to 'useFalse'}} + // expected-note@#USE_FALSE{{constraints not satisfied}} + // expected-note@#USE_FALSE_CONSTR{{because 'int' does not satisfy 'FalseConstraint2'}} + // expected-note@#FC2_CONSTR {{would be invalid: no matching function for call to 'func'}} +} +} // namespace SubConstraintChecks + +namespace DeducedTemplateArgs { +template struct ItrTraits { + template struct Ptr { + }; + template + requires requires { typename PtrItr::pointer; } + struct Ptr { + using type = typename Itr::pointer; + }; + using pointer = typename Ptr::type; // #TRAITS_PTR +}; + +struct complete_itr { + using pointer = int; +}; + +template class Complete { + using ItrType = ItrTraits; + ItrType begin() noexcept { return ItrType(); } +}; + +// This version doesn't have 'pointer', so error confirms we are in the first +// verison of 'Ptr'. +struct not_complete_itr { +}; + +template class NotComplete { + using ItrType = ItrTraits; + ItrType begin() noexcept { return ItrType(); } + // expected-error@#TRAITS_PTR{{no type named 'type' in }} + // expected-note@-2{{in instantiation of template class }} +}; +} + +namespace DeferredInstantiationInstScope { +template +struct remove_ref { + using type = T; +}; +template +struct remove_ref { + using type = T; +}; +template +struct remove_ref { + using type = T; +}; + +template +constexpr bool IsInt = PR54443::is_same::type, + int>::value; + +template +void SingleDepthReferencesTop(U &&u) { + struct lc { + void operator()() // #SDRT_OP + requires IsInt // #SDRT_REQ + {} + }; + lc lv; + lv(); // #SDRT_CALL +} + +template +void SingleDepthReferencesTopNotCalled(U &&u) { + struct lc { + void operator()() + requires IsInt + {} + }; + lc lv; +} + +template +void SingleDepthReferencesTopCalled(U &&u) { + struct lc { + void operator()() // #CALLOP + requires IsInt // #CONSTR + {} + }; + lc lv; + lv(); + // expected-error@-1{{no matching function for call to object of type 'lc'}} + // expected-note@#SDRTC{{in instantiation of function template}} + // expected-note@#CALLOP{{constraints not satisfied}} + // expected-note@#CONSTR{{substituted constraint expression is ill-formed}} +} + +template +void SingleDepthReferencesTopLambda(U &&u) { + []() + requires IsInt + {}(); +} + +template +void DoubleDepthReferencesTop(U &&u) { + struct lc { // #DDRT_STRCT + void operator()() { + struct lc2 { + void operator()() // #DDRT_OP + requires IsInt // #DDRT_REQ + {} + }; + lc2 lv2; + lv2(); // #DDRT_CALL + } + }; + lc lv; + lv(); +} + +template +void DoubleDepthReferencesTopLambda(U &&u) { + []() { []() + requires IsInt + {}(); }(); +} + +template +void DoubleDepthReferencesAll(U &&u) { + struct lc { // #DDRA_STRCT + void operator()(U &&u2) { + struct lc2 { + void operator()(U &&u3) // #DDRA_OP + requires IsInt && // #DDRA_REQ + IsInt && IsInt + {} + }; + lc2 lv2; + lv2(u2); // #DDRA_CALL + } + }; + lc lv; + lv(u); +} + +template +void DoubleDepthReferencesAllLambda(U &&u) { + [](U &&u2) { + [](U && u3) + requires IsInt && + IsInt && IsInt + {}(u2); + }(u); +} + +template +struct CausesFriendConstraint { + template + friend void FriendFunc(CausesFriendConstraint, V) // #FF_DECL + requires IsInt && + IsInt // #FF_REQ + {} +}; +// FIXME: Re-enable this test when constraints are allowed to refer to captures. +// template +// void ChecksCapture(T x) { +// [y = x]() requires(IsInt){}(); +// } + +template +void ChecksLocalVar(T x) { + T Local; + []() + requires(IsInt) + {}(); +} + +template +void LocalStructMemberVar(T x) { + struct S { + T local; + void foo() + requires(IsInt) // #LSMV_REQ + {} + } s; + s.foo(); // #LSMV_CALL +}; + +template +struct ChecksMemberVar { + T t; + void foo() + requires(IsInt) // #CMV_FOO + {} + template + void foo2() // #CMV_FOO2 + requires(IsInt) // #CMV_FOO2_REQ + {} +}; + +void test_dependent() { + int v = 0; + float will_fail; + SingleDepthReferencesTop(v); + SingleDepthReferencesTop(will_fail); + // expected-error@#SDRT_CALL{{no matching function for call to object of type 'lc'}} + // expected-note@-2{{in instantiation of function template specialization}} + // expected-note@#SDRT_OP{{candidate function not viable}} + // expected-note@#SDRT_REQ{{'IsInt' evaluated to false}} + + SingleDepthReferencesTopNotCalled(v); + // Won't error unless we try to call it. + SingleDepthReferencesTopNotCalled(will_fail); + SingleDepthReferencesTopCalled(v); // #SDRTC + SingleDepthReferencesTopLambda(v); + // FIXME: This should error on constraint failure! (Lambda!) + SingleDepthReferencesTopLambda(will_fail); + DoubleDepthReferencesTop(v); + DoubleDepthReferencesTop(will_fail); + // expected-error@#DDRT_CALL{{no matching function for call to object of type 'lc2'}} + // expected-note@-2{{in instantiation of function template specialization}} + // expected-note@#DDRT_STRCT{{in instantiation of member function}} + // expected-note@#DDRT_OP{{candidate function not viable}} + // expected-note@#DDRT_REQ{{'IsInt' evaluated to false}} + + DoubleDepthReferencesTopLambda(v); + // FIXME: This should error on constraint failure! (Lambda!) + DoubleDepthReferencesTopLambda(will_fail); + DoubleDepthReferencesAll(v); + DoubleDepthReferencesAll(will_fail); + // expected-error@#DDRA_CALL{{no matching function for call to object of type 'lc2'}} + // expected-note@-2{{in instantiation of function template specialization}} + // expected-note@#DDRA_STRCT{{in instantiation of member function}} + // expected-note@#DDRA_OP{{candidate function not viable}} + // expected-note@#DDRA_REQ{{'IsInt' evaluated to false}} + + DoubleDepthReferencesAllLambda(v); + // FIXME: This should error on constraint failure! (Lambda!) + DoubleDepthReferencesAllLambda(will_fail); + + CausesFriendConstraint CFC; + FriendFunc(CFC, 1); + FriendFunc(CFC, 1.0); + // expected-error@-1{{no matching function for call to 'FriendFunc'}} + // expected-note@#FF_DECL{{constraints not satisfied}} + // expected-note@#FF_REQ{{because 'IsInt' evaluated to false}} + + // FIXME: Re-enable this test when constraints are allowed to refer to captures. + // ChecksCapture(v); + + ChecksLocalVar(v); + // FIXME: This should error on constraint failure! (Lambda!) + ChecksLocalVar(will_fail); + + LocalStructMemberVar(v); + LocalStructMemberVar(will_fail); + // expected-error@#LSMV_CALL{{invalid reference to function 'foo'}} + // expected-note@-2{{in instantiation of function template specialization}} + // expected-note@#LSMV_REQ{{because 'IsIntlocal)>' evaluated to false}} + + ChecksMemberVar CMV; + CMV.foo(); + CMV.foo2(); + + ChecksMemberVar CMV2; + CMV2.foo(); + // expected-error@-1{{invalid reference to function 'foo'}} + // expected-note@#CMV_FOO{{because 'IsIntt)>' evaluated to false}} + CMV2.foo2(); + // expected-error@-1{{no matching member function for call to 'foo2'}} + // expected-note@#CMV_FOO2{{constraints not satisfied}} + // expected-note@#CMV_FOO2_REQ{{because 'IsIntt)>' evaluated to false}} +} +} // namespace DeferredInstantiationInstScope + + Index: clang/test/SemaTemplate/deferred-concept-inst.cpp =================================================================== --- /dev/null +++ clang/test/SemaTemplate/deferred-concept-inst.cpp @@ -0,0 +1,23 @@ +// RUN: %clang_cc1 -std=c++2a -x c++ %s -verify -fsyntax-only -Wno-unused-value +// expected-no-diagnostics + +namespace GithubBug44178 { +template +struct CRTP { + void call_foo() + requires requires(D &v) { v.foo(); } + { + static_cast(this)->foo(); + } +}; + +struct Test : public CRTP { + void foo() {} +}; + +int main() { + Test t; + t.call_foo(); + return 0; +} +} // namespace GithubBug44178 Index: clang/test/SemaTemplate/instantiate-requires-clause.cpp =================================================================== --- clang/test/SemaTemplate/instantiate-requires-clause.cpp +++ clang/test/SemaTemplate/instantiate-requires-clause.cpp @@ -1,4 +1,4 @@ -// RUN: %clang_cc1 -std=c++2a -x c++ %s -verify +// RUN: %clang_cc1 -std=c++2a -x c++ %s -Wno-unused-value -verify template requires ((sizeof(Args) == 1), ...) // expected-note@-1 {{because '(sizeof(int) == 1) , (sizeof(char) == 1) , (sizeof(int) == 1)' evaluated to false}} @@ -40,6 +40,20 @@ static_assert(S::f(1)); +// Similar to the 'S' test, but tries to use 'U' in the requires clause. +template +struct S1 { + // expected-note@+3 {{candidate template ignored: constraints not satisfied [with U = int]}} + // expected-note@+3 {{because substituted constraint expression is ill-formed: type 'int' cannot be used prior to '::' because it has no members}} + template + static constexpr auto f(U const index) + requires(U::foo) + { return true; } +}; + +// expected-error@+1 {{no matching function for call to 'f'}} +static_assert(S1::f(1)); + constexpr auto value = 0; template Index: clang/test/SemaTemplate/trailing-return-short-circuit.cpp =================================================================== --- /dev/null +++ clang/test/SemaTemplate/trailing-return-short-circuit.cpp @@ -0,0 +1,62 @@ +// RUN: %clang_cc1 -std=c++20 -verify %s + +template + requires(sizeof(T) > 2) || T::value // #FOO_REQ +void Foo(T){}; // #FOO + +template +void TrailingReturn(T) // #TRAILING + requires(sizeof(T) > 2) || // #TRAILING_REQ + T::value // #TRAILING_REQ_VAL +{}; +template +struct HasValue { + static constexpr bool value = B; +}; +static_assert(sizeof(HasValue) <= 2); + +template +struct HasValueLarge { + static constexpr bool value = B; + int I; +}; +static_assert(sizeof(HasValueLarge) > 2); + +void usage() { + // Passes the 1st check, short-circuit so the 2nd ::value is not evaluated. + Foo(1.0); + TrailingReturn(1.0); + + // Fails the 1st check, but has a ::value, so the check happens correctly. + Foo(HasValue{}); + TrailingReturn(HasValue{}); + + // Passes the 1st check, but would have passed the 2nd one. + Foo(HasValueLarge{}); + TrailingReturn(HasValueLarge{}); + + // Fails the 1st check, fails 2nd because there is no ::value. + Foo(true); + // expected-error@-1{{no matching function for call to 'Foo'}} + // expected-note@#FOO{{candidate template ignored: constraints not satisfied [with T = bool]}} + // expected-note@#FOO_REQ{{because 'sizeof(_Bool) > 2' (1 > 2) evaluated to false}} + // expected-note@#FOO_REQ{{because substituted constraint expression is ill-formed: type 'bool' cannot be used prior to '::' because it has no members}} + + TrailingReturn(true); + // expected-error@-1{{no matching function for call to 'TrailingReturn'}} + // expected-note@#TRAILING{{candidate template ignored: constraints not satisfied [with T = bool]}} + // expected-note@#TRAILING_REQ{{because 'sizeof(_Bool) > 2' (1 > 2) evaluated to false}} + // expected-note@#TRAILING_REQ_VAL{{because substituted constraint expression is ill-formed: type 'bool' cannot be used prior to '::' because it has no members}} + + // Fails the 1st check, fails 2nd because ::value is false. + Foo(HasValue{}); + // expected-error@-1 {{no matching function for call to 'Foo'}} + // expected-note@#FOO{{candidate template ignored: constraints not satisfied [with T = HasValue]}} + // expected-note@#FOO_REQ{{because 'sizeof(HasValue) > 2' (1 > 2) evaluated to false}} + // expected-note@#FOO_REQ{{and 'HasValue::value' evaluated to false}} + TrailingReturn(HasValue{}); + // expected-error@-1 {{no matching function for call to 'TrailingReturn'}} + // expected-note@#TRAILING{{candidate template ignored: constraints not satisfied [with T = HasValue]}} + // expected-note@#TRAILING_REQ{{because 'sizeof(HasValue) > 2' (1 > 2) evaluated to false}} + // expected-note@#TRAILING_REQ_VAL{{and 'HasValue::value' evaluated to false}} +}