llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: None (antangelo) <details> <summary>Changes</summary> Emit a deprecation warning when a variadic parameter in a parameter-declaration-clause is not preceded by a comma for C++26. --- Full diff: https://github.com/llvm/llvm-project/pull/117524.diff 7 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+2) - (modified) clang/include/clang/Basic/DiagnosticGroups.td (+3-1) - (modified) clang/include/clang/Basic/DiagnosticParseKinds.td (+3) - (modified) clang/lib/Parse/ParseDecl.cpp (+8) - (modified) clang/test/CXX/drs/cwg722.cpp (+1-1) - (added) clang/test/Parser/cxx2c-oxford-variadic-comma.cpp (+36) - (modified) clang/www/cxx_status.html (+1-1) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 8bd06fadfdc984..b8d5c4201aeaef 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -227,6 +227,8 @@ C++2c Feature Support - Added the ``__builtin_is_within_lifetime`` builtin, which supports `P2641R4 Checking if a union alternative is active <https://wg21.link/p2641r4>`_ +- Implemented `P3176R1 The Oxford variadic comma <https://wg21.link/P3176R1>`_ + C++23 Feature Support ^^^^^^^^^^^^^^^^^^^^^ - Removed the restriction to literal types in constexpr functions in C++23 mode. diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td index df9bf94b5d0398..7ad8ac0e7a2e46 100644 --- a/clang/include/clang/Basic/DiagnosticGroups.td +++ b/clang/include/clang/Basic/DiagnosticGroups.td @@ -211,6 +211,7 @@ def DeprecatedWritableStr : DiagGroup<"deprecated-writable-strings", [CXX11CompatDeprecatedWritableStr]>; def DeprecatedPragma : DiagGroup<"deprecated-pragma">; def DeprecatedType : DiagGroup<"deprecated-type">; +def DeprecatedMissingCommaVariadicParam : DiagGroup<"deprecated-missing-comma-variadic-parameter">; // FIXME: Why is DeprecatedImplementations not in this group? def Deprecated : DiagGroup<"deprecated", [DeprecatedAnonEnumEnumConversion, DeprecatedArrayCompare, @@ -235,7 +236,8 @@ def Deprecated : DiagGroup<"deprecated", [DeprecatedAnonEnumEnumConversion, DeprecatedType, DeprecatedVolatile, DeprecatedWritableStr, - DeprecatedRedundantConstexprStaticDef + DeprecatedRedundantConstexprStaticDef, + DeprecatedMissingCommaVariadicParam ]>, DiagCategory<"Deprecations">; diff --git a/clang/include/clang/Basic/DiagnosticParseKinds.td b/clang/include/clang/Basic/DiagnosticParseKinds.td index 77bf08453dea51..7c3961059d1d0d 100644 --- a/clang/include/clang/Basic/DiagnosticParseKinds.td +++ b/clang/include/clang/Basic/DiagnosticParseKinds.td @@ -413,6 +413,9 @@ def err_function_scope_depth_exceeded : Error< "function scope depth exceeded maximum of %0">, DefaultFatal; def err_missing_comma_before_ellipsis : Error< "C requires a comma prior to the ellipsis in a variadic function type">; +def warn_deprecated_missing_comma_before_ellipsis : Warning< + "variadic parameters that are not preceded by a comma are deprecated">, + InGroup<DeprecatedMissingCommaVariadicParam>; def err_unexpected_typedef_ident : Error< "unexpected type name %0: expected identifier">; def warn_cxx98_compat_decltype : Warning< diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp index aa5c2d28d429ac..d28a74662aefe0 100644 --- a/clang/lib/Parse/ParseDecl.cpp +++ b/clang/lib/Parse/ParseDecl.cpp @@ -8119,6 +8119,14 @@ void Parser::ParseParameterDeclarationClause( } if (TryConsumeToken(tok::ellipsis, EllipsisLoc)) { + if (getLangOpts().CPlusPlus26) { + // C++26 [dcl.dcl.fct]p3: + // A parameter-declaration-clause of the form + // parameter-list '...' is deprecated + Diag(EllipsisLoc, diag::warn_deprecated_missing_comma_before_ellipsis) + << FixItHint::CreateInsertion(EllipsisLoc, ", "); + } + if (!getLangOpts().CPlusPlus) { // We have ellipsis without a preceding ',', which is ill-formed // in C. Complain and provide the fix. diff --git a/clang/test/CXX/drs/cwg722.cpp b/clang/test/CXX/drs/cwg722.cpp index e90d9af360d9d0..6e7d4569c55381 100644 --- a/clang/test/CXX/drs/cwg722.cpp +++ b/clang/test/CXX/drs/cwg722.cpp @@ -14,7 +14,7 @@ namespace std { using nullptr_t = decltype(nullptr); } -void f(std::nullptr_t...); +void f(std::nullptr_t, ...); std::nullptr_t g(); void h() { std::nullptr_t np; diff --git a/clang/test/Parser/cxx2c-oxford-variadic-comma.cpp b/clang/test/Parser/cxx2c-oxford-variadic-comma.cpp new file mode 100644 index 00000000000000..dc78dcbb6b074f --- /dev/null +++ b/clang/test/Parser/cxx2c-oxford-variadic-comma.cpp @@ -0,0 +1,36 @@ +// RUN: %clang_cc1 -std=c++2c -fsyntax-only -verify %s + +void a(...); + +void b(auto...); +void c(auto, ...); + +void d(auto......); // expected-warning {{variadic parameters that are not preceded by a comma are deprecated}} \ + // expected-warning {{'...' in this location creates a C-style varargs function}} \ + // expected-note {{preceding '...' declares a function parameter pack}} \ + // expected-note {{insert ',' before '...' to silence this warning}} +void e(auto..., ...); + +void f(auto x...); // expected-warning {{variadic parameters that are not preceded by a comma are deprecated}} +void g(auto x, ...); + +void h(auto... x...); // expected-warning {{variadic parameters that are not preceded by a comma are deprecated}} \ + // expected-warning {{'...' in this location creates a C-style varargs function}} \ + // expected-note {{preceding '...' declares a function parameter pack}} \ + // expected-note {{insert ',' before '...' to silence this warning}} +void i(auto... x, ...); + +template<class ...T> +void j(T... t...); // expected-warning {{variadic parameters that are not preceded by a comma are deprecated}} \ + // expected-warning {{'...' in this location creates a C-style varargs function}} \ + // expected-note {{preceding '...' declares a function parameter pack}} \ + // expected-note {{insert ',' before '...' to silence this warning}} +template<class ...T> +void k(T... t, ...); + +void l(int...); // expected-warning {{variadic parameters that are not preceded by a comma are deprecated}} +void m(int, ...); + +void n(int x...); // expected-warning {{variadic parameters that are not preceded by a comma are deprecated}} +void o(int x, ...); + diff --git a/clang/www/cxx_status.html b/clang/www/cxx_status.html index da01cf6ceab59b..fdb9807b1168c7 100755 --- a/clang/www/cxx_status.html +++ b/clang/www/cxx_status.html @@ -249,7 +249,7 @@ <h2 id="cxx26">C++2c implementation status</h2> <tr> <td>The Oxford variadic comma</td> <td><a href="https://wg21.link/P3176R1";>P3176R1</a></td> - <td class="none" align="center">No</td> + <td class="unreleased" align="center">Clang 20</td> </tr> </table> </details> `````````` </details> https://github.com/llvm/llvm-project/pull/117524 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
