https://github.com/sdkrystian updated https://github.com/llvm/llvm-project/pull/88042
>From 9c3b78f1f37049224f31e3bcd07ae8d762b760d1 Mon Sep 17 00:00:00 2001 From: Krystian Stasiowski <sdkryst...@gmail.com> Date: Mon, 8 Apr 2024 09:46:08 -0400 Subject: [PATCH] [Clang][Sema] Implement approved resolution for CWG2858 --- clang/include/clang/Basic/DiagnosticSemaKinds.td | 7 +++---- clang/lib/Sema/SemaDecl.cpp | 13 ++++++------- .../expr.prim.id/expr.prim.id.qual/p3.cpp | 16 ++++++++++++++++ 3 files changed, 25 insertions(+), 11 deletions(-) diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index a1dda2d2461c31..2b9077173aa426 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -2402,10 +2402,6 @@ def err_selected_explicit_constructor : Error< def note_explicit_ctor_deduction_guide_here : Note< "explicit %select{constructor|deduction guide}0 declared here">; -// C++11 decltype -def err_decltype_in_declarator : Error< - "'decltype' cannot be used to name a declaration">; - // C++11 auto def warn_cxx98_compat_auto_type_specifier : Warning< "'auto' type specifier is incompatible with C++98">, @@ -8302,6 +8298,9 @@ def ext_template_after_declarative_nns : ExtWarn< def ext_alias_template_in_declarative_nns : ExtWarn< "a declarative nested name specifier cannot name an alias template">, InGroup<DiagGroup<"alias-template-in-declaration-name">>; +def err_computed_type_in_declarative_nns : Error< + "%select{a pack indexing type|'decltype'}0 cannot be used in " + "a declarative nested name specifier">; def err_no_typeid_with_fno_rtti : Error< "use of typeid requires -frtti">; diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp index c790dab72dd721..1ba6b3beb1c758 100644 --- a/clang/lib/Sema/SemaDecl.cpp +++ b/clang/lib/Sema/SemaDecl.cpp @@ -6335,16 +6335,15 @@ bool Sema::diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC, if (TST->isDependentType() && TST->isTypeAlias()) Diag(Loc, diag::ext_alias_template_in_declarative_nns) << SpecLoc.getLocalSourceRange(); - } else if (T->isDecltypeType()) { + } else if (T->isDecltypeType() || T->getAsAdjusted<PackIndexingType>()) { // C++23 [expr.prim.id.qual]p2: // [...] A declarative nested-name-specifier shall not have a - // decltype-specifier. + // computed-type-specifier. // - // FIXME: This wording appears to be defective as it does not forbid - // declarative nested-name-specifiers with pack-index-specifiers. - // See https://github.com/cplusplus/CWG/issues/499. - Diag(Loc, diag::err_decltype_in_declarator) - << SpecLoc.getTypeLoc().getSourceRange(); + // CWG2858 changed this from 'decltype-specifier' to + // 'computed-type-specifier'. + Diag(Loc, diag::err_computed_type_in_declarative_nns) + << T->isDecltypeType() << SpecLoc.getTypeLoc().getSourceRange(); } } } while ((SpecLoc = SpecLoc.getPrefix())); diff --git a/clang/test/CXX/expr/expr.prim/expr.prim.id/expr.prim.id.qual/p3.cpp b/clang/test/CXX/expr/expr.prim/expr.prim.id/expr.prim.id.qual/p3.cpp index c73ffa55a26a31..5da13cc22abef2 100644 --- a/clang/test/CXX/expr/expr.prim/expr.prim.id/expr.prim.id.qual/p3.cpp +++ b/clang/test/CXX/expr/expr.prim/expr.prim.id/expr.prim.id.qual/p3.cpp @@ -1,4 +1,5 @@ // RUN: %clang_cc1 -verify %s +// RUN: %clang_cc1 -std=c++2c -verify %s template<typename T> struct A { @@ -27,3 +28,18 @@ namespace N { template<typename T> void N::E<T>::f() { } // expected-warning {{a declarative nested name specifier cannot name an alias template}} + +#if __cplusplus > 202302L +template<typename... Ts> +struct A { + // FIXME: The nested-name-specifier in the following friend declarations are declarative, + // but we don't treat them as such (yet). + friend void Ts...[0]::f(); + template<typename U> + friend void Ts...[0]::g(); + + friend struct Ts...[0]::B; + template<typename U> + friend struct Ts...[0]::C; // expected-warning{{is not supported; ignoring this friend declaration}} +}; +#endif _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits