diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index e44aefa90ab38..adce4c1e3a63a 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -256,6 +256,8 @@ C++2c Feature Support - Added the ``__builtin_is_within_lifetime`` builtin, which supports `P2641R4 Checking if a union alternative is active `_ +- Implemented `P3176R1 The Oxford variadic comma `_ + 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 438655a7eaca7..ac0e178d1cb41 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 77bf08453dea5..9fa8d5901bd0a 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< + "declaration of a variadic function without a comma before '...' is deprecated">, + InGroup; 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 aa5c2d28d429a..937a94b02458c 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 e90d9af360d9d..6e7d4569c5538 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 0000000000000..b8015b4815b2e --- /dev/null +++ b/clang/test/Parser/cxx2c-oxford-variadic-comma.cpp @@ -0,0 +1,54 @@ +// RUN: %clang_cc1 -std=c++2c -fsyntax-only -fblocks -verify %s + +void a(...); + +void b(auto...); +void c(auto, ...); + +void d(auto......); // expected-warning {{declaration of a variadic function without a comma before '...' is 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 {{declaration of a variadic function without a comma before '...' is deprecated}} +void g(auto x, ...); + +void h(auto... x...); // expected-warning {{declaration of a variadic function without a comma before '...' is 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 +void j(Ts... t...) {}; // expected-warning {{declaration of a variadic function without a comma before '...' is 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 +void k(Ts... t, ...) {} + +void l(int...); // expected-warning {{declaration of a variadic function without a comma before '...' is deprecated}} +void m(int, ...); + +void n(int x...); // expected-warning {{declaration of a variadic function without a comma before '...' is deprecated}} +void o(int x, ...); + +struct S { + void p(this S...) {} // expected-warning {{declaration of a variadic function without a comma before '...' is deprecated}} +}; + +template +void q(Ts......) {} // expected-warning {{declaration of a variadic function without a comma before '...' is 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 +void r(T...) {} // expected-warning {{declaration of a variadic function without a comma before '...' is deprecated}} + +auto type_specifier = (void (*)(int...)) nullptr; // expected-warning {{declaration of a variadic function without a comma before '...' is deprecated}} + +auto lambda = [](int...) {}; // expected-warning {{declaration of a variadic function without a comma before '...' is deprecated}} + +auto block = ^(int...){}; // expected-warning {{declaration of a variadic function without a comma before '...' is deprecated}} diff --git a/clang/www/cxx_status.html b/clang/www/cxx_status.html index da01cf6ceab59..fdb9807b1168c 100755 --- a/clang/www/cxx_status.html +++ b/clang/www/cxx_status.html @@ -249,7 +249,7 @@

C++2c implementation status

The Oxford variadic comma P3176R1 - No + Clang 20