Author: Aaron Ballman Date: 2024-02-16T15:08:04-05:00 New Revision: 97434cb318d170a14914126f33181b759197ba41
URL: https://github.com/llvm/llvm-project/commit/97434cb318d170a14914126f33181b759197ba41 DIFF: https://github.com/llvm/llvm-project/commit/97434cb318d170a14914126f33181b759197ba41.diff LOG: [C11] Diagnose C11 keywords as being incompatible w/earlier standards (#82015) Our usual pattern when issuing an extension warning is to also issue a default-off diagnostic about the keywords not being compatible with standards before a certain point. This adds those diagnostics for C11 keywords. Added: clang/test/Parser/c11-keywords.c Modified: clang/docs/ReleaseNotes.rst clang/include/clang/Basic/DiagnosticGroups.td clang/include/clang/Basic/DiagnosticParseKinds.td clang/include/clang/Parse/Parser.h clang/lib/Parse/ParseDecl.cpp clang/lib/Parse/ParseDeclCXX.cpp clang/lib/Parse/ParseExpr.cpp clang/lib/Parse/Parser.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 16f79a349c20c8..06c7d57d73ca70 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -185,6 +185,9 @@ Improvements to Clang's diagnostics - Clang now diagnoses friend declarations with an ``enum`` elaborated-type-specifier in language modes after C++98. +- Added diagnostics for C11 keywords being incompatible with language standards + before C11, under a new warning group: ``-Wpre-c11-compat``. + Improvements to Clang's time-trace ---------------------------------- diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td index 7679b8528a4197..e8b4139d7893ce 100644 --- a/clang/include/clang/Basic/DiagnosticGroups.td +++ b/clang/include/clang/Basic/DiagnosticGroups.td @@ -290,6 +290,9 @@ def : DiagGroup<"c++1z-compat-mangling", [CXX17CompatMangling]>; def NoexceptType : DiagGroup<"noexcept-type", [CXX17CompatMangling]>; // Warnings for C code which is not compatible with previous C standards. +def CPre11Compat : DiagGroup<"pre-c11-compat">; +def CPre11CompatPedantic : DiagGroup<"pre-c11-compat-pedantic", + [CPre11Compat]>; def CPre23Compat : DiagGroup<"pre-c23-compat">; def CPre23CompatPedantic : DiagGroup<"pre-c23-compat-pedantic", [CPre23Compat]>; diff --git a/clang/include/clang/Basic/DiagnosticParseKinds.td b/clang/include/clang/Basic/DiagnosticParseKinds.td index 11b490a0928e60..c0dbc25a0c3265 100644 --- a/clang/include/clang/Basic/DiagnosticParseKinds.td +++ b/clang/include/clang/Basic/DiagnosticParseKinds.td @@ -165,6 +165,9 @@ def ext_c99_feature : Extension< "'%0' is a C99 extension">, InGroup<C99>; def ext_c11_feature : Extension< "'%0' is a C11 extension">, InGroup<C11>; +def warn_c11_compat_keyword : Warning< + "'%0' is incompatible with C standards before C11">, + InGroup<CPre11Compat>, DefaultIgnore; def warn_c23_compat_keyword : Warning< "'%0' is incompatible with C standards before C23">, InGroup<CPre23Compat>, DefaultIgnore; diff --git a/clang/include/clang/Parse/Parser.h b/clang/include/clang/Parse/Parser.h index 69b9e837fe8bef..071520f535bc95 100644 --- a/clang/include/clang/Parse/Parser.h +++ b/clang/include/clang/Parse/Parser.h @@ -1122,6 +1122,8 @@ class Parser : public CodeCompletionHandler { void checkCompoundToken(SourceLocation FirstTokLoc, tok::TokenKind FirstTokKind, CompoundToken Op); + void diagnoseUseOfC11Keyword(const Token &Tok); + public: //===--------------------------------------------------------------------===// // Scope manipulation diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp index 9640d7ee70d27f..0728113ba7c936 100644 --- a/clang/lib/Parse/ParseDecl.cpp +++ b/clang/lib/Parse/ParseDecl.cpp @@ -3520,8 +3520,7 @@ void Parser::ParseDeclarationSpecifiers( // alignment-specifier case tok::kw__Alignas: - if (!getLangOpts().C11) - Diag(Tok, diag::ext_c11_feature) << Tok.getName(); + diagnoseUseOfC11Keyword(Tok); [[fallthrough]]; case tok::kw_alignas: // _Alignas and alignas (C23, not C++) should parse the same way. The C++ @@ -4184,8 +4183,7 @@ void Parser::ParseDeclarationSpecifiers( isStorageClass = true; break; case tok::kw__Thread_local: - if (!getLangOpts().C11) - Diag(Tok, diag::ext_c11_feature) << Tok.getName(); + diagnoseUseOfC11Keyword(Tok); isInvalid = DS.SetStorageClassSpecThread(DeclSpec::TSCS__Thread_local, Loc, PrevSpec, DiagID); isStorageClass = true; @@ -4245,8 +4243,7 @@ void Parser::ParseDeclarationSpecifiers( break; } case tok::kw__Noreturn: - if (!getLangOpts().C11) - Diag(Tok, diag::ext_c11_feature) << Tok.getName(); + diagnoseUseOfC11Keyword(Tok); isInvalid = DS.setFunctionSpecNoreturn(Loc, PrevSpec, DiagID); break; @@ -4576,9 +4573,7 @@ void Parser::ParseDeclarationSpecifiers( // If the _Atomic keyword is immediately followed by a left parenthesis, // it is interpreted as a type specifier (with a type name), not as a // type qualifier. - if (!getLangOpts().C11) - Diag(Tok, diag::ext_c11_feature) << Tok.getName(); - + diagnoseUseOfC11Keyword(Tok); if (NextToken().is(tok::l_paren)) { ParseAtomicSpecifier(DS); continue; @@ -6154,8 +6149,7 @@ void Parser::ParseTypeQualifierListOpt( case tok::kw__Atomic: if (!AtomicAllowed) goto DoneWithTypeQuals; - if (!getLangOpts().C11) - Diag(Tok, diag::ext_c11_feature) << Tok.getName(); + diagnoseUseOfC11Keyword(Tok); isInvalid = DS.SetTypeQual(DeclSpec::TQ_atomic, Loc, PrevSpec, DiagID, getLangOpts()); break; diff --git a/clang/lib/Parse/ParseDeclCXX.cpp b/clang/lib/Parse/ParseDeclCXX.cpp index 7d0dbc4ac69490..62632b2d79792e 100644 --- a/clang/lib/Parse/ParseDeclCXX.cpp +++ b/clang/lib/Parse/ParseDeclCXX.cpp @@ -968,9 +968,9 @@ Decl *Parser::ParseStaticAssertDeclaration(SourceLocation &DeclEnd) { // Save the token name used for static assertion. const char *TokName = Tok.getName(); - if (Tok.is(tok::kw__Static_assert) && !getLangOpts().C11) - Diag(Tok, diag::ext_c11_feature) << Tok.getName(); - if (Tok.is(tok::kw_static_assert)) { + if (Tok.is(tok::kw__Static_assert)) + diagnoseUseOfC11Keyword(Tok); + else if (Tok.is(tok::kw_static_assert)) { if (!getLangOpts().CPlusPlus) { if (getLangOpts().C23) Diag(Tok, diag::warn_c23_compat_keyword) << Tok.getName(); diff --git a/clang/lib/Parse/ParseExpr.cpp b/clang/lib/Parse/ParseExpr.cpp index 52cebdb6f64bac..f1417456ffe510 100644 --- a/clang/lib/Parse/ParseExpr.cpp +++ b/clang/lib/Parse/ParseExpr.cpp @@ -1462,8 +1462,7 @@ ExprResult Parser::ParseCastExpression(CastParseKind ParseKind, return Res; } case tok::kw__Alignof: // unary-expression: '_Alignof' '(' type-name ')' - if (!getLangOpts().C11) - Diag(Tok, diag::ext_c11_feature) << Tok.getName(); + diagnoseUseOfC11Keyword(Tok); [[fallthrough]]; case tok::kw_alignof: // unary-expression: 'alignof' '(' type-id ')' case tok::kw___alignof: // unary-expression: '__alignof' unary-expression @@ -3389,8 +3388,8 @@ ExprResult Parser::ParseStringLiteralExpression(bool AllowUserDefinedLiteral, /// \endverbatim ExprResult Parser::ParseGenericSelectionExpression() { assert(Tok.is(tok::kw__Generic) && "_Generic keyword expected"); - if (!getLangOpts().C11) - Diag(Tok, diag::ext_c11_feature) << Tok.getName(); + + diagnoseUseOfC11Keyword(Tok); SourceLocation KeyLoc = ConsumeToken(); BalancedDelimiterTracker T(*this, tok::l_paren); diff --git a/clang/lib/Parse/Parser.cpp b/clang/lib/Parse/Parser.cpp index 2dd4a73bfbc262..1701d153bd0eca 100644 --- a/clang/lib/Parse/Parser.cpp +++ b/clang/lib/Parse/Parser.cpp @@ -2742,6 +2742,15 @@ bool Parser::parseMisplacedModuleImport() { return false; } +void Parser::diagnoseUseOfC11Keyword(const Token &Tok) { + // Warn that this is a C11 extension if in an older mode or if in C++. + // Otherwise, warn that it is incompatible with standards before C11 if in + // C11 or later. + Diag(Tok, getLangOpts().C11 ? diag::warn_c11_compat_keyword + : diag::ext_c11_feature) + << Tok.getName(); +} + bool BalancedDelimiterTracker::diagnoseOverflow() { P.Diag(P.Tok, diag::err_bracket_depth_exceeded) << P.getLangOpts().BracketDepth; diff --git a/clang/test/Parser/c11-keywords.c b/clang/test/Parser/c11-keywords.c new file mode 100644 index 00000000000000..2621e1a1a8595d --- /dev/null +++ b/clang/test/Parser/c11-keywords.c @@ -0,0 +1,37 @@ +// RUN: %clang_cc1 %s -std=c11 -fsyntax-only -verify=compat -Wpre-c11-compat +// RUN: %clang_cc1 %s -std=c99 -fsyntax-only -verify=ext -pedantic +// RUN: %clang_cc1 %s -std=c11 -fsyntax-only -verify=good +// RUN: %clang_cc1 -x c++ %s -fsyntax-only -verify=ext -pedantic + +// good-no-diagnostics + +extern _Noreturn void exit(int); /* compat-warning {{'_Noreturn' is incompatible with C standards before C11}} + ext-warning {{'_Noreturn' is a C11 extension}} + */ + +void func(void) { + static _Thread_local int tl; /* compat-warning {{'_Thread_local' is incompatible with C standards before C11}} + ext-warning {{'_Thread_local' is a C11 extension}} + */ + _Alignas(8) char c; /* compat-warning {{'_Alignas' is incompatible with C standards before C11}} + ext-warning {{'_Alignas' is a C11 extension}} + */ + _Atomic int i1; /* compat-warning {{'_Atomic' is incompatible with C standards before C11}} + ext-warning {{'_Atomic' is a C11 extension}} + */ + _Atomic(int) i2; /* compat-warning {{'_Atomic' is incompatible with C standards before C11}} + ext-warning {{'_Atomic' is a C11 extension}} + */ + + _Static_assert(1, ""); /* compat-warning {{'_Static_assert' is incompatible with C standards before C11}} + ext-warning {{'_Static_assert' is a C11 extension}} + */ + + (void)_Generic(1, int : 1); /* compat-warning {{'_Generic' is incompatible with C standards before C11}} + ext-warning {{'_Generic' is a C11 extension}} + */ + (void)_Alignof(int); /* compat-warning {{'_Alignof' is incompatible with C standards before C11}} + ext-warning {{'_Alignof' is a C11 extension}} + */ +} + _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
