Author: Aaron Ballman Date: 2022-05-05T14:00:01-04:00 New Revision: 967137ca3cb7cf38b2fedf0415946ff3ffd0ef50
URL: https://github.com/llvm/llvm-project/commit/967137ca3cb7cf38b2fedf0415946ff3ffd0ef50 DIFF: https://github.com/llvm/llvm-project/commit/967137ca3cb7cf38b2fedf0415946ff3ffd0ef50.diff LOG: No longer accept scoped enumerations in C We had a think-o that would allow a user to declare a scoped enumeration in C language modes "as a C++11 extension". This is a think-o because there's no way for the user to spell the name of the enumerators; C does not have '::' for a fully-qualified name. See commit d0d87b597259a2b74ae5c2825a081c7e336cb1d0 for details on why this is unintentional for C. Fixes #42372 Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Parse/ParseDecl.cpp clang/test/Sema/enum.c Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index f5e9cd941e091..87e4df50ae0f2 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -142,6 +142,11 @@ Bug Fixes - Fixed a false positive diagnostic about an unevaluated expression having no side effects when the expression is of VLA type and is an operand of the ``sizeof`` operator. Fixes `Issue 48010 <https://github.com/llvm/llvm-project/issues/48010>`_. +- Fixed a false positive diagnostic about scoped enumerations being a C++11 + extension in C mode. A scoped enumeration's enumerators cannot be named in C + because there is no way to fully qualify the enumerator name, so this + "extension" was unintentional and useless. This fixes + `Issue 42372 <https://github.com/llvm/llvm-project/issues/42372>`_. Improvements to Clang's diagnostics ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp index 3d18ffe07ee6b..8d6e84b924c32 100644 --- a/clang/lib/Parse/ParseDecl.cpp +++ b/clang/lib/Parse/ParseDecl.cpp @@ -4531,7 +4531,7 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS, bool IsScopedUsingClassTag = false; // In C++11, recognize 'enum class' and 'enum struct'. - if (Tok.isOneOf(tok::kw_class, tok::kw_struct)) { + if (Tok.isOneOf(tok::kw_class, tok::kw_struct) && getLangOpts().CPlusPlus) { Diag(Tok, getLangOpts().CPlusPlus11 ? diag::warn_cxx98_compat_scoped_enum : diag::ext_scoped_enum); IsScopedUsingClassTag = Tok.is(tok::kw_class); diff --git a/clang/test/Sema/enum.c b/clang/test/Sema/enum.c index ae4a8a357e179..0fe54d791aff5 100644 --- a/clang/test/Sema/enum.c +++ b/clang/test/Sema/enum.c @@ -159,3 +159,16 @@ struct EnumRedeclStruct { PR15071_One // expected-error {{redefinition of enumerator 'PR15071_One'}} } e; }; + +enum struct GH42372_1 { // expected-error {{expected identifier or '{'}} expected-warning {{declaration does not declare anything}} + One +}; + +// Because class is not a keyword in C, this looks like a forward declaration. +// expected-error@+4 {{expected ';' after top level declarator}} +// expected-error@+3 {{tentative definition has type 'enum class' that is never completed}} +// expected-warning@+2 {{ISO C forbids forward references to 'enum' types}} +// expected-note@+1 {{forward declaration of 'enum class'}} +enum class GH42372_2 { + One +}; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
