https://github.com/Serosh-commits updated https://github.com/llvm/llvm-project/pull/180407
>From 99a7cd2f824e1c0c34200631ddca9ee41d480d06 Mon Sep 17 00:00:00 2001 From: Serosh-commits <[email protected]> Date: Sun, 8 Feb 2026 17:40:06 +0530 Subject: [PATCH] [clang][sema] fix crash on builtin template ids with dependent packs (gh180307) --- clang/lib/Sema/SemaTemplate.cpp | 23 ++++++++-------- .../builtin_templates_invalid_parameters.cpp | 26 +++++++++++++++++++ 2 files changed, 38 insertions(+), 11 deletions(-) create mode 100644 clang/test/SemaCXX/builtin_templates_invalid_parameters.cpp diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp index 3497ff7856eed..47db53f512a0c 100644 --- a/clang/lib/Sema/SemaTemplate.cpp +++ b/clang/lib/Sema/SemaTemplate.cpp @@ -3406,10 +3406,16 @@ static QualType checkBuiltinTemplateIdType( Sema &SemaRef, ElaboratedTypeKeyword Keyword, BuiltinTemplateDecl *BTD, ArrayRef<TemplateArgument> Converted, SourceLocation TemplateLoc, TemplateArgumentListInfo &TemplateArgs) { + if (Converted.size() < BTD->getTemplateParameters()->size()) + return QualType(); + ASTContext &Context = SemaRef.getASTContext(); switch (BTD->getBuiltinTemplateKind()) { case BTK__make_integer_seq: { + assert(Converted.size() == 3); + if (Converted[2].isDependent()) + return QualType(); // Specializations of __make_integer_seq<S, T, N> are treated like // S<T, 0, ..., N-1>. @@ -3423,8 +3429,6 @@ static QualType checkBuiltinTemplateIdType( } TemplateArgument NumArgsArg = Converted[2]; - if (NumArgsArg.isDependent()) - return QualType(); TemplateArgumentListInfo SyntheticTemplateArgs; // The type argument, wrapped in substitution sugar, gets reused as the @@ -3459,15 +3463,12 @@ static QualType checkBuiltinTemplateIdType( } case BTK__type_pack_element: { - // Specializations of - // __type_pack_element<Index, T_1, ..., T_N> - // are treated like T_Index. assert(Converted.size() == 2 && "__type_pack_element should be given an index and a parameter pack"); + if (Converted[0].isDependent() || Converted[1].isDependent()) + return QualType(); TemplateArgument IndexArg = Converted[0], Ts = Converted[1]; - if (IndexArg.isDependent() || Ts.isDependent()) - return QualType(); llvm::APSInt Index = IndexArg.getAsIntegral(); assert(Index >= 0 && "the index used with __type_pack_element should be of " @@ -3486,7 +3487,7 @@ static QualType checkBuiltinTemplateIdType( case BTK__builtin_common_type: { assert(Converted.size() == 4); - if (llvm::any_of(Converted, [](auto &C) { return C.isDependent(); })) + if (Converted[3].isDependent()) return QualType(); TemplateName BaseTemplate = Converted[0].getAsTemplate(); @@ -3509,14 +3510,14 @@ static QualType checkBuiltinTemplateIdType( case BTK__hlsl_spirv_type: { assert(Converted.size() == 4); + if (llvm::any_of(Converted, + [](const TemplateArgument &A) { return A.isDependent(); })) + return QualType(); if (!Context.getTargetInfo().getTriple().isSPIRV()) { SemaRef.Diag(TemplateLoc, diag::err_hlsl_spirv_only) << BTD; } - if (llvm::any_of(Converted, [](auto &C) { return C.isDependent(); })) - return QualType(); - uint64_t Opcode = Converted[0].getAsIntegral().getZExtValue(); uint64_t Size = Converted[1].getAsIntegral().getZExtValue(); uint64_t Alignment = Converted[2].getAsIntegral().getZExtValue(); diff --git a/clang/test/SemaCXX/builtin_templates_invalid_parameters.cpp b/clang/test/SemaCXX/builtin_templates_invalid_parameters.cpp new file mode 100644 index 0000000000000..0209ffad6eec5 --- /dev/null +++ b/clang/test/SemaCXX/builtin_templates_invalid_parameters.cpp @@ -0,0 +1,26 @@ +// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s +// expected-error@* {{template argument for non-type template parameter must be an expression}} + +using SizeT = decltype(sizeof(int)); + +// Dependent cases that previously crashed but now return QualType() gracefully. +template <SizeT... Seq> // expected-note {{template parameter is declared here}} +using gh180307 = __type_pack_element<Seq...>; + +template <typename T> +using gh180307_bis = __make_integer_seq<gh180307, T>; +// expected-note@-1 {{template template argument has different template parameters than its corresponding template template parameter}} + +// Eager expansion checks: Built-in templates should expand even if the +// destination template OR the type argument is dependent, provided the size is known. +template <template <typename T, T... Ints> class Seq> +using test_make_integer_seq_eager = __make_integer_seq<Seq, int, 2>; + +template <typename T, T... Ints> struct MySeq; +using check_eager = test_make_integer_seq_eager<MySeq>; +using check_eager = MySeq<int, 0, 1>; + +template <typename T> +using test_make_integer_seq_type_dependent = __make_integer_seq<MySeq, T, 2>; +using check_type_eager = test_make_integer_seq_type_dependent<int>; +using check_type_eager = MySeq<int, 0, 1>; _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
