Author: Matheus Izvekov Date: 2025-03-25T16:56:10-07:00 New Revision: ecde8c235e5e09ff71789725c96416f8daf93cd7
URL: https://github.com/llvm/llvm-project/commit/ecde8c235e5e09ff71789725c96416f8daf93cd7 DIFF: https://github.com/llvm/llvm-project/commit/ecde8c235e5e09ff71789725c96416f8daf93cd7.diff LOG: [clang] fix matching of nested template template parameters When checking the template template parameters of template template parameters, the PartialOrdering context was not correctly propagated. This also has a few drive-by fixes, such as checking the template parameter lists of template template parameters, which was previously missing and would have been it's own bug, but we need to fix it in order to prevent crashes in error recovery in a simple way. Fixes #130362 Backport of: https://github.com/llvm/llvm-project/pull/130447 Added: Modified: clang/docs/ReleaseNotes.rst clang/include/clang/Sema/Sema.h clang/lib/Sema/SemaDecl.cpp clang/lib/Sema/SemaDeclCXX.cpp clang/lib/Sema/SemaTemplate.cpp clang/lib/Sema/SemaTemplateDeduction.cpp clang/lib/Sema/SemaTemplateInstantiateDecl.cpp clang/test/SemaTemplate/cwg2398.cpp clang/test/SemaTemplate/temp_arg_template_p0522.cpp clang/unittests/AST/DeclPrinterTest.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 955325026f369..c921ac3518f01 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -1058,6 +1058,9 @@ Bug Fixes to C++ Support - Fixed a substitution bug in transforming CTAD aliases when the type alias contains a non-pack template argument corresponding to a pack parameter (#GH124715) - Clang is now better at keeping track of friend function template instance contexts. (#GH55509) +- Fixes matching of nested template template parameters. (#GH130362) +- Correctly diagnoses template template paramters which have a pack parameter + not in the last position. - Fixed an integer overflow bug in computing template parameter depths when synthesizing CTAD guides. (#GH128691) - Fixed an incorrect pointer access when checking access-control on concepts. (#GH131530) - Fixed various alias CTAD bugs involving variadic template arguments. (#GH123591), (#GH127539), (#GH129077), diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h index cecf5cff332f4..d8cc0171c22c6 100644 --- a/clang/include/clang/Sema/Sema.h +++ b/clang/include/clang/Sema/Sema.h @@ -11279,14 +11279,16 @@ class Sema final : public SemaBase { /// The context in which we are checking a template parameter list. enum TemplateParamListContext { - TPC_ClassTemplate, - TPC_VarTemplate, + // For this context, Class, Variable, TypeAlias, and non-pack Template + // Template Parameters are treated uniformly. + TPC_Other, + TPC_FunctionTemplate, TPC_ClassTemplateMember, TPC_FriendClassTemplate, TPC_FriendFunctionTemplate, TPC_FriendFunctionTemplateDefinition, - TPC_TypeAliasTemplate + TPC_TemplateTemplateParameterPack, }; /// Checks the validity of a template parameter list, possibly diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp index f70401ea33b4a..41d5f9f2f3420 100644 --- a/clang/lib/Sema/SemaDecl.cpp +++ b/clang/lib/Sema/SemaDecl.cpp @@ -8145,7 +8145,7 @@ NamedDecl *Sema::ActOnVariableDeclarator( (D.getCXXScopeSpec().isSet() && DC && DC->isRecord() && DC->isDependentContext()) ? TPC_ClassTemplateMember - : TPC_VarTemplate)) + : TPC_Other)) NewVD->setInvalidDecl(); // If we are providing an explicit specialization of a static variable diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp index e4e3bbad1f520..85de46c9adab4 100644 --- a/clang/lib/Sema/SemaDeclCXX.cpp +++ b/clang/lib/Sema/SemaDeclCXX.cpp @@ -13533,7 +13533,7 @@ Decl *Sema::ActOnAliasDeclaration(Scope *S, AccessSpecifier AS, // Merge any previous default template arguments into our parameters, // and check the parameter list. if (CheckTemplateParameterList(TemplateParams, OldTemplateParams, - TPC_TypeAliasTemplate)) + TPC_Other)) return nullptr; TypeAliasTemplateDecl *NewDecl = diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp index 938671055333c..1c555b38277b0 100644 --- a/clang/lib/Sema/SemaTemplate.cpp +++ b/clang/lib/Sema/SemaTemplate.cpp @@ -1591,8 +1591,16 @@ NamedDecl *Sema::ActOnTemplateTemplateParameter( assert(S->isTemplateParamScope() && "Template template parameter not in template parameter scope!"); - // Construct the parameter object. bool IsParameterPack = EllipsisLoc.isValid(); + + bool Invalid = false; + if (CheckTemplateParameterList( + Params, + /*OldParams=*/nullptr, + IsParameterPack ? TPC_TemplateTemplateParameterPack : TPC_Other)) + Invalid = true; + + // Construct the parameter object. TemplateTemplateParmDecl *Param = TemplateTemplateParmDecl::Create( Context, Context.getTranslationUnitDecl(), NameLoc.isInvalid() ? TmpLoc : NameLoc, Depth, Position, IsParameterPack, @@ -1615,9 +1623,12 @@ NamedDecl *Sema::ActOnTemplateTemplateParameter( if (Params->size() == 0) { Diag(Param->getLocation(), diag::err_template_template_parm_no_parms) << SourceRange(Params->getLAngleLoc(), Params->getRAngleLoc()); - Param->setInvalidDecl(); + Invalid = true; } + if (Invalid) + Param->setInvalidDecl(); + // C++0x [temp.param]p9: // A default template-argument may be specified for any kind of // template-parameter that is not a template parameter pack. @@ -2066,7 +2077,7 @@ DeclResult Sema::CheckClassTemplate( SemanticContext->isDependentContext()) ? TPC_ClassTemplateMember : TUK == TagUseKind::Friend ? TPC_FriendClassTemplate - : TPC_ClassTemplate, + : TPC_Other, SkipBody)) Invalid = true; @@ -2208,9 +2219,8 @@ static bool DiagnoseDefaultTemplateArgument(Sema &S, SourceLocation ParamLoc, SourceRange DefArgRange) { switch (TPC) { - case Sema::TPC_ClassTemplate: - case Sema::TPC_VarTemplate: - case Sema::TPC_TypeAliasTemplate: + case Sema::TPC_Other: + case Sema::TPC_TemplateTemplateParameterPack: return false; case Sema::TPC_FunctionTemplate: @@ -2383,8 +2393,11 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, MissingDefaultArg = true; } else if (NonTypeTemplateParmDecl *NewNonTypeParm = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { - // Check for unexpanded parameter packs. - if (!NewNonTypeParm->isParameterPack() && + // Check for unexpanded parameter packs, except in a template template + // parameter pack, as in those any unexpanded packs should be expanded + // along with the parameter itself. + if (TPC != TPC_TemplateTemplateParameterPack && + !NewNonTypeParm->isParameterPack() && DiagnoseUnexpandedParameterPack(NewNonTypeParm->getLocation(), NewNonTypeParm->getTypeSourceInfo(), UPPC_NonTypeTemplateParameterType)) { @@ -2492,8 +2505,7 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, // If a template parameter of a primary class template or alias template // is a template parameter pack, it shall be the last template parameter. if (SawParameterPack && (NewParam + 1) != NewParamEnd && - (TPC == TPC_ClassTemplate || TPC == TPC_VarTemplate || - TPC == TPC_TypeAliasTemplate)) { + (TPC == TPC_Other || TPC == TPC_TemplateTemplateParameterPack)) { Diag((*NewParam)->getLocation(), diag::err_template_param_pack_must_be_last_template_parameter); Invalid = true; @@ -2526,8 +2538,8 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, << PrevModuleName; Invalid = true; } else if (MissingDefaultArg && - (TPC == TPC_ClassTemplate || TPC == TPC_FriendClassTemplate || - TPC == TPC_VarTemplate || TPC == TPC_TypeAliasTemplate)) { + (TPC == TPC_Other || TPC == TPC_TemplateTemplateParameterPack || + TPC == TPC_FriendClassTemplate)) { // C++ 23[temp.param]p14: // If a template-parameter of a class template, variable template, or // alias template has a default template argument, each subsequent diff --git a/clang/lib/Sema/SemaTemplateDeduction.cpp b/clang/lib/Sema/SemaTemplateDeduction.cpp index 5304b5a2155b4..7a880505a53ff 100644 --- a/clang/lib/Sema/SemaTemplateDeduction.cpp +++ b/clang/lib/Sema/SemaTemplateDeduction.cpp @@ -3427,9 +3427,9 @@ static TemplateDeductionResult FinishTemplateArgumentDeduction( if (!P.isPackExpansion() && !A.isPackExpansion()) { Info.Param = makeTemplateParameter(Template->getTemplateParameters()->getParam( - (PsStack.empty() ? TemplateArgs.end() - : PsStack.front().begin()) - - TemplateArgs.begin())); + (AsStack.empty() ? CTAI.CanonicalConverted.end() + : AsStack.front().begin()) - + 1 - CTAI.CanonicalConverted.begin())); Info.FirstArg = P; Info.SecondArg = A; return TemplateDeductionResult::NonDeducedMismatch; @@ -6625,17 +6625,19 @@ bool Sema::isTemplateTemplateParameterAtLeastAsSpecializedAs( TemplateDeductionResult TDK; runWithSufficientStackSpace(Info.getLocation(), [&] { - TDK = ::FinishTemplateArgumentDeduction( - *this, AArg, /*IsPartialOrdering=*/true, PArgs, Deduced, Info); + TDK = ::FinishTemplateArgumentDeduction(*this, AArg, PartialOrdering, PArgs, + Deduced, Info); }); switch (TDK) { case TemplateDeductionResult::Success: return true; // It doesn't seem possible to get a non-deduced mismatch when partial - // ordering TTPs. + // ordering TTPs, except with an invalid template parameter list which has + // a parameter after a pack. case TemplateDeductionResult::NonDeducedMismatch: - llvm_unreachable("Unexpected NonDeducedMismatch"); + assert(PArg->isInvalidDecl() && "Unexpected NonDeducedMismatch"); + return false; // Substitution failures should have already been diagnosed. case TemplateDeductionResult::AlreadyDiagnosed: diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp index 89ad2a0a9b7bb..0c25b87439a95 100644 --- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp +++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp @@ -1827,7 +1827,7 @@ Decl *TemplateDeclInstantiator::VisitClassTemplateDecl(ClassTemplateDecl *D) { // Do some additional validation, then merge default arguments // from the existing declarations. if (SemaRef.CheckTemplateParameterList(InstParams, PrevParams, - Sema::TPC_ClassTemplate)) + Sema::TPC_Other)) return nullptr; Inst->setAccess(PrevClassTemplate->getAccess()); diff --git a/clang/test/SemaTemplate/cwg2398.cpp b/clang/test/SemaTemplate/cwg2398.cpp index 8592be469bb50..33b288acce82a 100644 --- a/clang/test/SemaTemplate/cwg2398.cpp +++ b/clang/test/SemaTemplate/cwg2398.cpp @@ -650,6 +650,11 @@ namespace regression3 { template struct A<B, Node<None>>; // old-error@-1 {{ diff erent template}} } // namespace regression3 +namespace GH130362 { + template <template <template <class... T1> class TT1> class TT2> struct A {}; + template <template <class U1> class UU1> struct B {}; + template struct A<B>; +} // namespace GH130362 namespace nttp_auto { namespace t1 { @@ -658,26 +663,19 @@ namespace nttp_auto { template struct A<B>; } // namespace t1 namespace t2 { - // FIXME: Shouldn't accept parameters after a parameter pack. template<template<auto... Va1, auto Va2> class> struct A {}; - // new-error@-1 {{deduced non-type template argument does not have the same type as the corresponding template parameter ('auto' vs 'int')}} - // expected-note@-2 {{previous template template parameter is here}} + // expected-error@-1 {{template parameter pack must be the last template parameter}} + // old-note@-2 {{previous template template parameter is here}} template<int... Vi> struct B; - // new-note@-1 {{template parameter is declared here}} - // old-note@-2 {{too few template parameters}} + // old-note@-1 {{too few template parameters}} template struct A<B>; - // new-note@-1 {{ diff erent template parameters}} - // old-error@-2 {{ diff erent template parameters}} + // old-error@-1 {{ diff erent template parameters}} } // namespace t2 namespace t3 { - // FIXME: Shouldn't accept parameters after a parameter pack. template<template<auto... Va1, auto... Va2> class> struct A {}; - // new-error@-1 {{deduced non-type template argument does not have the same type as the corresponding template parameter ('auto' vs 'int')}} - // new-note@-2 {{previous template template parameter is here}} + // expected-error@-1 {{template parameter pack must be the last template parameter}} template<int... Vi> struct B; - // new-note@-1 {{template parameter is declared here}} template struct A<B>; - // new-note@-1 {{ diff erent template parameters}} } // namespace t3 } // namespace nttp_auto diff --git a/clang/test/SemaTemplate/temp_arg_template_p0522.cpp b/clang/test/SemaTemplate/temp_arg_template_p0522.cpp index 2e5a36ae6ed08..d8a81bb363112 100644 --- a/clang/test/SemaTemplate/temp_arg_template_p0522.cpp +++ b/clang/test/SemaTemplate/temp_arg_template_p0522.cpp @@ -7,7 +7,8 @@ template<template<int> typename> struct Ti; // #Ti template<template<int...> typename> struct TPi; // #TPi template<template<int, int...> typename> struct TiPi; -template<template<int..., int...> typename> struct TPiPi; // FIXME: Why is this not ill-formed? +template<template<int..., int...> typename> struct TPiPi; +// expected-error@-1 {{template parameter pack must be the last template parameter}} template<typename T, template<T> typename> struct tT0; // #tT0 template<template<typename T, T> typename> struct Tt0; // #Tt0 diff --git a/clang/unittests/AST/DeclPrinterTest.cpp b/clang/unittests/AST/DeclPrinterTest.cpp index 6945dff537cae..124b1a166cb18 100644 --- a/clang/unittests/AST/DeclPrinterTest.cpp +++ b/clang/unittests/AST/DeclPrinterTest.cpp @@ -1196,21 +1196,21 @@ TEST(DeclPrinter, TestUnnamedTemplateParameters) { } TEST(DeclPrinter, TestUnnamedTemplateParametersPacks) { - ASSERT_TRUE(PrintedDeclCXX17Matches( - "template <typename ..., int ...," - " template <typename ..., bool ...> class ...> void A();", - functionTemplateDecl(hasName("A")).bind("id"), - "template <typename ..., int ...," - " template <typename ..., bool ...> class ...> void A()")); + ASSERT_TRUE( + PrintedDeclCXX17Matches("template <typename ..., int ...," + " template <typename ...> class ...> void A();", + functionTemplateDecl(hasName("A")).bind("id"), + "template <typename ..., int ...," + " template <typename ...> class ...> void A()")); } TEST(DeclPrinter, TestNamedTemplateParametersPacks) { ASSERT_TRUE(PrintedDeclCXX17Matches( "template <typename ...T, int ...I," - " template <typename ...X, bool ...B> class ...Z> void A();", + " template <typename ...X> class ...Z> void A();", functionTemplateDecl(hasName("A")).bind("id"), "template <typename ...T, int ...I," - " template <typename ...X, bool ...B> class ...Z> void A()")); + " template <typename ...X> class ...Z> void A()")); } TEST(DeclPrinter, TestTemplateTemplateParameterWrittenWithTypename) { _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
