Author: Younan Zhang Date: 2024-10-11T10:31:27+08:00 New Revision: 0bc02b999a9686ba240b7a68d3f1cbbf037d2170
URL: https://github.com/llvm/llvm-project/commit/0bc02b999a9686ba240b7a68d3f1cbbf037d2170 DIFF: https://github.com/llvm/llvm-project/commit/0bc02b999a9686ba240b7a68d3f1cbbf037d2170.diff LOG: [Clang] Instantiate Typedefs referenced by type alias deduction guides (#111804) TypedefNameDecl referenced by a synthesized CTAD guide for type aliases was not transformed previously, resulting in a substitution failure in BuildDeductionGuideForTypeAlias() when substituting into the right-hand-side deduction guide. This patch fixes it in the way we have been doing since https://reviews.llvm.org/D80743. We transform all the function parameters, parenting referenced TypedefNameDecls with the CXXDeductionGuideDecl. Then we instantiate these declarations in FindInstantiatedDecl() as we build up the eventual deduction guide, using the mechanism introduced in D80743 Fixes #111508 Added: Modified: clang/lib/Sema/SemaTemplateDeductionGuide.cpp clang/test/SemaCXX/cxx20-ctad-type-alias.cpp Removed: ################################################################################ diff --git a/clang/lib/Sema/SemaTemplateDeductionGuide.cpp b/clang/lib/Sema/SemaTemplateDeductionGuide.cpp index 545da21183c3c4..2d3e58548fb7ac 100644 --- a/clang/lib/Sema/SemaTemplateDeductionGuide.cpp +++ b/clang/lib/Sema/SemaTemplateDeductionGuide.cpp @@ -70,8 +70,8 @@ class ExtractTypeForDeductionGuide ExtractTypeForDeductionGuide( Sema &SemaRef, llvm::SmallVectorImpl<TypedefNameDecl *> &MaterializedTypedefs, - ClassTemplateDecl *NestedPattern, - const MultiLevelTemplateArgumentList *OuterInstantiationArgs) + ClassTemplateDecl *NestedPattern = nullptr, + const MultiLevelTemplateArgumentList *OuterInstantiationArgs = nullptr) : Base(SemaRef), MaterializedTypedefs(MaterializedTypedefs), NestedPattern(NestedPattern), OuterInstantiationArgs(OuterInstantiationArgs) { @@ -1228,10 +1228,25 @@ FunctionTemplateDecl *DeclareAggregateDeductionGuideForTypeAlias( getRHSTemplateDeclAndArgs(SemaRef, AliasTemplate).first; if (!RHSTemplate) return nullptr; + + llvm::SmallVector<TypedefNameDecl *> TypedefDecls; + llvm::SmallVector<QualType> NewParamTypes; + ExtractTypeForDeductionGuide TypeAliasTransformer(SemaRef, TypedefDecls); + for (QualType P : ParamTypes) { + QualType Type = TypeAliasTransformer.TransformType(P); + if (Type.isNull()) + return nullptr; + NewParamTypes.push_back(Type); + } + auto *RHSDeductionGuide = SemaRef.DeclareAggregateDeductionGuideFromInitList( - RHSTemplate, ParamTypes, Loc); + RHSTemplate, NewParamTypes, Loc); if (!RHSDeductionGuide) return nullptr; + + for (TypedefNameDecl *TD : TypedefDecls) + TD->setDeclContext(RHSDeductionGuide->getTemplatedDecl()); + return BuildDeductionGuideForTypeAlias(SemaRef, AliasTemplate, RHSDeductionGuide, Loc); } diff --git a/clang/test/SemaCXX/cxx20-ctad-type-alias.cpp b/clang/test/SemaCXX/cxx20-ctad-type-alias.cpp index 5392573fcdb9d5..675c32a81f1ae8 100644 --- a/clang/test/SemaCXX/cxx20-ctad-type-alias.cpp +++ b/clang/test/SemaCXX/cxx20-ctad-type-alias.cpp @@ -481,3 +481,16 @@ struct Out { Out<float>::B out(100); // deduced to Out<float>::A<float>; static_assert(__is_same(decltype(out), Out<float>::A<float>)); } + +namespace GH111508 { + +template <typename V> struct S { + using T = V; + T Data; +}; + +template <typename V> using Alias = S<V>; + +Alias A(42); + +} // namespace GH111508 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
