llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: None (offsetof) <details> <summary>Changes</summary> CWG2815 "Overload resolution for references/pointers to `noexcept` functions" --- Full diff: https://github.com/llvm/llvm-project/pull/132778.diff 5 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+4) - (modified) clang/lib/Sema/SemaExprCXX.cpp (+2-1) - (modified) clang/lib/Sema/SemaOverload.cpp (+21-13) - (modified) clang/test/CXX/drs/cwg28xx.cpp (+22) - (modified) clang/www/cxx_dr_status.html (+40-4) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 8182bccdd2da8..a3af19f79d9c3 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -110,12 +110,16 @@ Resolutions to C++ Defect Reports two releases. The improvements to template template parameter matching implemented in the previous release, as described in P3310 and P3579, made this flag unnecessary. +- Implemented |CWG2815|_ - Implemented `CWG2918 Consideration of constraints for address of overloaded ` `function <https://cplusplus.github.io/CWG/issues/2918.html>`_ - Bumped the ``__cpp_constexpr`` feature-test macro to ``202002L`` in C++20 mode as indicated in `P2493R0 <https://wg21.link/P2493R0>`_. +.. |CWG2815| replace:: CWG2815 Overload resolution for references/pointers to ``noexcept`` functions +.. _CWG2815: https://cplusplus.github.io/CWG/issues/2815 + C Language Changes ------------------ diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp index 856b505e92214..da13c9c7db401 100644 --- a/clang/lib/Sema/SemaExprCXX.cpp +++ b/clang/lib/Sema/SemaExprCXX.cpp @@ -4907,7 +4907,8 @@ Sema::PerformImplicitConversion(Expr *From, QualType ToType, if (CheckExceptionSpecCompatibility(From, ToType)) return ExprError(); - From = ImpCastExprToType(From, ToType, CK_NoOp, VK_PRValue, + From = ImpCastExprToType(From, ToType.getNonReferenceType(), CK_NoOp, + From->getValueKind(), /*BasePath=*/nullptr, CCK) .get(); break; diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp index 6d8006b35dcf4..aa55bf03edaa0 100644 --- a/clang/lib/Sema/SemaOverload.cpp +++ b/clang/lib/Sema/SemaOverload.cpp @@ -5229,10 +5229,23 @@ TryReferenceInit(Sema &S, Expr *Init, QualType DeclType, S.CompareReferenceRelationship(DeclLoc, T1, T2, &RefConv); auto SetAsReferenceBinding = [&](bool BindsDirectly) { + // C++2c [over.ics.ref] p1: + // When a parameter of type "reference to cv T" binds directly + // to an argument expression: + // * If the argument expression has a type that is a derived class + // of the parameter type, the implicit conversion sequence is a + // derived-to-base conversion. + // * Otherwise, if the type of the argument is possibly cv-qualified T, + // or if T is an array type of unknown bound with element type U + // and the argument has an array type of known bound whose element + // type is possibly cv-qualified U, the implicit conversion + // sequence is the identity conversion. + // * Otherwise, if T is a function type, the implicit conversion + // sequence is a function pointer conversion. + // * Otherwise, the implicit conversion sequence is a qualification + // conversion. ICS.setStandard(); ICS.Standard.First = ICK_Identity; - // FIXME: A reference binding can be a function conversion too. We should - // consider that when ordering reference-to-function bindings. ICS.Standard.Second = (RefConv & Sema::ReferenceConversions::DerivedToBase) ? ICK_Derived_To_Base : (RefConv & Sema::ReferenceConversions::ObjC) @@ -5242,10 +5255,12 @@ TryReferenceInit(Sema &S, Expr *Init, QualType DeclType, // FIXME: As a speculative fix to a defect introduced by CWG2352, we rank // a reference binding that performs a non-top-level qualification // conversion as a qualification conversion, not as an identity conversion. - ICS.Standard.Third = (RefConv & - Sema::ReferenceConversions::NestedQualification) - ? ICK_Qualification - : ICK_Identity; + ICS.Standard.Third = + (RefConv & Sema::ReferenceConversions::Function) + ? ICK_Function_Conversion + : (RefConv & Sema::ReferenceConversions::NestedQualification) + ? ICK_Qualification + : ICK_Identity; ICS.Standard.setFromType(T2); ICS.Standard.setToType(0, T2); ICS.Standard.setToType(1, T1); @@ -5273,13 +5288,6 @@ TryReferenceInit(Sema &S, Expr *Init, QualType DeclType, // // Per C++ [over.ics.ref]p4, we don't check the bit-field property here. if (InitCategory.isLValue() && RefRelationship == Sema::Ref_Compatible) { - // C++ [over.ics.ref]p1: - // When a parameter of reference type binds directly (8.5.3) - // to an argument expression, the implicit conversion sequence - // is the identity conversion, unless the argument expression - // has a type that is a derived class of the parameter type, - // in which case the implicit conversion sequence is a - // derived-to-base Conversion (13.3.3.1). SetAsReferenceBinding(/*BindsDirectly=*/true); // Nothing more to do: the inaccessibility/ambiguity check for diff --git a/clang/test/CXX/drs/cwg28xx.cpp b/clang/test/CXX/drs/cwg28xx.cpp index b32e649374893..3f65b7b7e46da 100644 --- a/clang/test/CXX/drs/cwg28xx.cpp +++ b/clang/test/CXX/drs/cwg28xx.cpp @@ -47,6 +47,28 @@ void f() { #endif } // namespace cwg2813 +namespace cwg2815 { // cwg2815: 21 +#if __cpp_noexcept_function_type >= 201510 +int arg() noexcept; + +int f(int (&)() noexcept); +void f(int (&)()); +int i = f(arg); + +int g(int (*)() noexcept); +void g(int (&)()); +int j = g(arg); + +int h(int (&)() noexcept); +void h(int (*)()); +int k = h(arg); + +int a(int (*)()); // expected-note {{candidate function}} +int a(int (&)()); // expected-note {{candidate function}} +int x = a(arg); // expected-error {{call to 'a' is ambiguous}} +#endif +} // namespace cwg2815 + namespace cwg2819 { // cwg2819: 19 c++26 #if __cplusplus >= 201103L // CWG 2024-04-19: This issue is not a DR. diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html index 16a9b26052f87..4590bcec6df9e 100755 --- a/clang/www/cxx_dr_status.html +++ b/clang/www/cxx_dr_status.html @@ -12529,11 +12529,11 @@ <h2 id="cxxdr">C++ defect report implementation status</h2> <td>Direct or copy initialization for omitted aggregate initializers</td> <td class="unknown" align="center">Unknown</td> </tr> - <tr class="open" id="2117"> + <tr id="2117"> <td><a href="https://cplusplus.github.io/CWG/issues/2117.html";>2117</a></td> - <td>open</td> + <td>NAD</td> <td>Explicit specializations and <TT>constexpr</TT> function templates</td> - <td align="center">Not resolved</td> + <td class="unknown" align="center">Unknown</td> </tr> <tr class="open" id="2118"> <td><a href="https://cplusplus.github.io/CWG/issues/2118.html";>2118</a></td> @@ -16738,7 +16738,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2> <td><a href="https://cplusplus.github.io/CWG/issues/2815.html";>2815</a></td> <td>DR</td> <td>Overload resolution for references/pointers to <TT>noexcept</TT> functions</td> - <td class="unknown" align="center">Unknown</td> + <td class="unreleased" align="center">Clang 21</td> </tr> <tr class="open" id="2816"> <td><a href="https://cplusplus.github.io/CWG/issues/2816.html";>2816</a></td> @@ -17909,6 +17909,42 @@ <h2 id="cxxdr">C++ defect report implementation status</h2> <td>open</td> <td>Missing Annex C entry for <TT>void</TT> object declarations</td> <td align="center">Not resolved</td> + </tr> + <tr class="open" id="3009"> + <td><a href="https://cplusplus.github.io/CWG/issues/3009.html";>3009</a></td> + <td>open</td> + <td>Unclear rules for constant initialization</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="3010"> + <td><a href="https://cplusplus.github.io/CWG/issues/3010.html";>3010</a></td> + <td>open</td> + <td>constexpr placement-new should require transparent replaceability</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="3011"> + <td><a href="https://cplusplus.github.io/CWG/issues/3011.html";>3011</a></td> + <td>open</td> + <td>Parenthesized aggregate initialization for <I>new-expression</I>s</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="3012"> + <td><a href="https://cplusplus.github.io/CWG/issues/3012.html";>3012</a></td> + <td>open</td> + <td>Deviating <TT>constexpr</TT> or <TT>consteval</TT> across translation units</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="3013"> + <td><a href="https://cplusplus.github.io/CWG/issues/3013.html";>3013</a></td> + <td>open</td> + <td>Disallowing macros for <TT>#embed</TT> parameters</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="3014"> + <td><a href="https://cplusplus.github.io/CWG/issues/3014.html";>3014</a></td> + <td>open</td> + <td>Comma-delimited vs. comma-separated output for <TT>#embed</TT></td> + <td align="center">Not resolved</td> </tr></table> </div> `````````` </details> https://github.com/llvm/llvm-project/pull/132778 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
