https://github.com/MitalAshok created https://github.com/llvm/llvm-project/pull/108817
https://cplusplus.github.io/CWG/issues/2915.html Previously, `struct A { void f(this void); };` was accepted with `A::f` being a member function with no non-object arguments, but it was still a little wonky because it was still considered an explicit object member function. Now, this is rejected immediately. This applies to any language mode with explicit object parameters as this is a DR (C++23 and C++26) >From f283645de806c71d93ec10bc7fcb933ccbfee156 Mon Sep 17 00:00:00 2001 From: Mital Ashok <mi...@mitalashok.co.uk> Date: Mon, 16 Sep 2024 12:22:01 +0100 Subject: [PATCH] [Clang] Reject "this void" (CWG2915) --- clang/docs/ReleaseNotes.rst | 3 + .../clang/Basic/DiagnosticSemaKinds.td | 2 + clang/lib/Sema/SemaType.cpp | 8 +++ clang/test/CXX/drs/cwg29xx.cpp | 8 +++ clang/www/cxx_dr_status.html | 68 +++++++++++++++++-- 5 files changed, 84 insertions(+), 5 deletions(-) diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 485b75049927fe..9c87a0d002b4ac 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -170,6 +170,9 @@ Resolutions to C++ Defect Reports in constant expressions. These comparisons always worked in non-constant expressions. (`CWG2749: Treatment of "pointer to void" for relational comparisons <https://cplusplus.github.io/CWG/issues/2749.html>`_). +- Reject explicit object parameters with type ``void`` (``this void``). + (`CWG2915: Explicit object parameters of type void <https://cplusplus.github.io/CWG/issues/2915.html>`_). + C Language Changes ------------------ diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td index d42558d2223aae..271f96e383e57d 100644 --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -4687,6 +4687,8 @@ def err_void_only_param : Error< "'void' must be the first and only parameter if specified">; def err_void_param_qualified : Error< "'void' as parameter must not have type qualifiers">; +def err_void_explicit_object_param : Error< + "explicit object parameter cannot have 'void' type">; def err_ident_list_in_fn_declaration : Error< "a parameter list without types is only allowed in a function definition">; def ext_param_not_declared : ExtWarn< diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp index e627fee51b66b8..7b99f5d13463fe 100644 --- a/clang/lib/Sema/SemaType.cpp +++ b/clang/lib/Sema/SemaType.cpp @@ -5166,6 +5166,14 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state, if (ParamTy.hasQualifiers()) S.Diag(DeclType.Loc, diag::err_void_param_qualified); + // Reject, but continue to parse 'float(this void)' as + // 'float(void)'. + if (Param->isExplicitObjectParameter()) { + S.Diag(Param->getLocation(), + diag::err_void_explicit_object_param); + Param->setExplicitObjectParameterLoc(SourceLocation()); + } + // Do not add 'void' to the list. break; } diff --git a/clang/test/CXX/drs/cwg29xx.cpp b/clang/test/CXX/drs/cwg29xx.cpp index ca598bb39a6c31..e55e8e35e86f28 100644 --- a/clang/test/CXX/drs/cwg29xx.cpp +++ b/clang/test/CXX/drs/cwg29xx.cpp @@ -6,6 +6,14 @@ // RUN: %clang_cc1 -std=c++23 -pedantic-errors -verify=expected %s // RUN: %clang_cc1 -std=c++2c -pedantic-errors -verify=expected %s +namespace cwg2915 { // cwg2915: 20 tentatively ready 2024-08-16 +#if __cplusplus >= 202302L +struct A { + void f(this void); // expected-error {{explicit object parameter cannot have 'void' type}} +}; +#endif +} + namespace cwg2917 { // cwg2917: 20 review 2024-07-30 template <typename> class Foo; diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html index f036fc5add2413..127bfe7e0e3724 100755 --- a/clang/www/cxx_dr_status.html +++ b/clang/www/cxx_dr_status.html @@ -11809,11 +11809,11 @@ <h2 id="cxxdr">C++ defect report implementation status</h2> <td>Reference list-initialization ignores conversion functions</td> <td align="center">Not resolved</td> </tr> - <tr class="open" id="1997"> + <tr id="1997"> <td><a href="https://cplusplus.github.io/CWG/issues/1997.html";>1997</a></td> - <td>drafting</td> + <td>DRWP</td> <td>Placement new and previous initialization</td> - <td align="center">Not resolved</td> + <td class="unknown" align="center">Unknown</td> </tr> <tr id="1998"> <td><a href="https://cplusplus.github.io/CWG/issues/1998.html";>1998</a></td> @@ -17346,11 +17346,15 @@ <h2 id="cxxdr">C++ defect report implementation status</h2> <td><a href="https://cplusplus.github.io/CWG/issues/2915.html";>2915</a></td> <td>tentatively ready</td> <td>Explicit object parameters of type <TT>void</TT></td> - <td align="center">Not resolved</td> + <td align="center"> + <details> + <summary>Not resolved</summary> + Clang 20 implements 2024-08-16 resolution + </details></td> </tr> <tr class="open" id="2916"> <td><a href="https://cplusplus.github.io/CWG/issues/2916.html";>2916</a></td> - <td>tentatively ready</td> + <td>review</td> <td>Variable template partial specializations should not be declared <TT>static</TT></td> <td align="center">Not resolved</td> </tr> @@ -17427,6 +17431,60 @@ <h2 id="cxxdr">C++ defect report implementation status</h2> <td>open</td> <td>Unclear status of translation unit with <TT>module</TT> keyword</td> <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2928"> + <td><a href="https://cplusplus.github.io/CWG/issues/2928.html";>2928</a></td> + <td>open</td> + <td>No ordering for initializing thread-local variables</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2929"> + <td><a href="https://cplusplus.github.io/CWG/issues/2929.html";>2929</a></td> + <td>open</td> + <td>Lifetime of trivially-destructible static or thread-local objects</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2930"> + <td><a href="https://cplusplus.github.io/CWG/issues/2930.html";>2930</a></td> + <td>open</td> + <td>Unclear term "copy/move operation" in specification of copy elision</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2931"> + <td><a href="https://cplusplus.github.io/CWG/issues/2931.html";>2931</a></td> + <td>open</td> + <td>Restrictions on operator functions that are explicit object member functions</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2932"> + <td><a href="https://cplusplus.github.io/CWG/issues/2932.html";>2932</a></td> + <td>open</td> + <td>Value range of empty enumeration</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2933"> + <td><a href="https://cplusplus.github.io/CWG/issues/2933.html";>2933</a></td> + <td>open</td> + <td>Dangling references</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2934"> + <td><a href="https://cplusplus.github.io/CWG/issues/2934.html";>2934</a></td> + <td>open</td> + <td>Unclear semantics of exception escaping from <TT>unhandled_exception</TT></td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2935"> + <td><a href="https://cplusplus.github.io/CWG/issues/2935.html";>2935</a></td> + <td>open</td> + <td>Destroying the coroutine state when initial-await-resume-called is false</td> + <td align="center">Not resolved</td> + </tr> + <tr class="open" id="2936"> + <td><a href="https://cplusplus.github.io/CWG/issues/2936.html";>2936</a></td> + <td>open</td> + <td>Local classes of templated functions should be part of the current instantiation</td> + <td align="center">Not resolved</td> </tr></table> </div> _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
