Author: Richard Smith Date: 2021-01-27T15:52:31-08:00 New Revision: ea99c885a63de9af673a5e5cd51f44fb70c83c1b
URL: https://github.com/llvm/llvm-project/commit/ea99c885a63de9af673a5e5cd51f44fb70c83c1b DIFF: https://github.com/llvm/llvm-project/commit/ea99c885a63de9af673a5e5cd51f44fb70c83c1b.diff LOG: Permit __VA_OPT__ in all language modes and allow it to be detected with #ifdef. These changes are intended to give code a path to move away from the GNU ,##__VA_ARGS__ extension, which is non-conforming in some situations and which we'd like to disable in our conforming mode in those cases. (cherry picked from commit 0436ec2128c9775ba13b0308937238fc79673fdd) Added: Modified: clang/include/clang/Lex/Preprocessor.h clang/include/clang/Lex/VariadicMacroSupport.h clang/lib/Lex/PPDirectives.cpp clang/lib/Lex/PPExpressions.cpp clang/lib/Lex/PPMacroExpansion.cpp clang/lib/Lex/Preprocessor.cpp clang/test/Preprocessor/macro_vaopt_check.cpp clang/test/Preprocessor/macro_vaopt_expand.cpp Removed: ################################################################################ diff --git a/clang/include/clang/Lex/Preprocessor.h b/clang/include/clang/Lex/Preprocessor.h index 68139cb24b31..ba8bdaa23c4c 100644 --- a/clang/include/clang/Lex/Preprocessor.h +++ b/clang/include/clang/Lex/Preprocessor.h @@ -447,6 +447,25 @@ class Preprocessor { ElseLoc(ElseLoc) {} }; + class IfdefMacroNameScopeRAII { + Preprocessor &PP; + bool VAOPTWasPoisoned; + + public: + IfdefMacroNameScopeRAII(Preprocessor &PP) + : PP(PP), VAOPTWasPoisoned(PP.Ident__VA_OPT__->isPoisoned()) { + PP.Ident__VA_OPT__->setIsPoisoned(false); + } + IfdefMacroNameScopeRAII(const IfdefMacroNameScopeRAII&) = delete; + IfdefMacroNameScopeRAII &operator=(const IfdefMacroNameScopeRAII&) = delete; + ~IfdefMacroNameScopeRAII() { Exit(); } + + void Exit() { + if (VAOPTWasPoisoned) + PP.Ident__VA_OPT__->setIsPoisoned(true); + } + }; + private: friend class ASTReader; friend class MacroArgs; diff --git a/clang/include/clang/Lex/VariadicMacroSupport.h b/clang/include/clang/Lex/VariadicMacroSupport.h index 989e0ac703c9..119f02201fc6 100644 --- a/clang/include/clang/Lex/VariadicMacroSupport.h +++ b/clang/include/clang/Lex/VariadicMacroSupport.h @@ -39,17 +39,14 @@ namespace clang { assert(Ident__VA_ARGS__->isPoisoned() && "__VA_ARGS__ should be poisoned " "outside an ISO C/C++ variadic " "macro definition!"); - assert( - !Ident__VA_OPT__ || - (Ident__VA_OPT__->isPoisoned() && "__VA_OPT__ should be poisoned!")); + assert(Ident__VA_OPT__->isPoisoned() && "__VA_OPT__ should be poisoned!"); } /// Client code should call this function just before the Preprocessor is /// about to Lex tokens from the definition of a variadic (ISO C/C++) macro. void enterScope() { Ident__VA_ARGS__->setIsPoisoned(false); - if (Ident__VA_OPT__) - Ident__VA_OPT__->setIsPoisoned(false); + Ident__VA_OPT__->setIsPoisoned(false); } /// Client code should call this function as soon as the Preprocessor has @@ -58,8 +55,7 @@ namespace clang { /// (might be explicitly called, and then reinvoked via the destructor). void exitScope() { Ident__VA_ARGS__->setIsPoisoned(true); - if (Ident__VA_OPT__) - Ident__VA_OPT__->setIsPoisoned(true); + Ident__VA_OPT__->setIsPoisoned(true); } ~VariadicMacroScopeGuard() { exitScope(); } diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp index d6b03d85913d..e2aa93455ea5 100644 --- a/clang/lib/Lex/PPDirectives.cpp +++ b/clang/lib/Lex/PPDirectives.cpp @@ -2928,9 +2928,14 @@ void Preprocessor::HandleIfdefDirective(Token &Result, ++NumIf; Token DirectiveTok = Result; + // __VA_OPT__ is allowed as the operand of #if[n]def. + IfdefMacroNameScopeRAII IfdefMacroNameScope(*this); + Token MacroNameTok; ReadMacroName(MacroNameTok); + IfdefMacroNameScope.Exit(); + // Error reading macro name? If so, diagnostic already issued. if (MacroNameTok.is(tok::eod)) { // Skip code until we get to #endif. This helps with recovery by not diff --git a/clang/lib/Lex/PPExpressions.cpp b/clang/lib/Lex/PPExpressions.cpp index 8c120c13d7d2..952fb8f121dc 100644 --- a/clang/lib/Lex/PPExpressions.cpp +++ b/clang/lib/Lex/PPExpressions.cpp @@ -104,6 +104,9 @@ static bool EvaluateDefined(PPValue &Result, Token &PeekTok, DefinedTracker &DT, SourceLocation beginLoc(PeekTok.getLocation()); Result.setBegin(beginLoc); + // __VA_OPT__ is allowed as the operand of 'defined'. + Preprocessor::IfdefMacroNameScopeRAII IfdefMacroNameScope(PP); + // Get the next token, don't expand it. PP.LexUnexpandedNonComment(PeekTok); @@ -122,6 +125,8 @@ static bool EvaluateDefined(PPValue &Result, Token &PeekTok, DefinedTracker &DT, PP.LexUnexpandedNonComment(PeekTok); } + IfdefMacroNameScope.Exit(); + // If we don't have a pp-identifier now, this is an error. if (PP.CheckMacroName(PeekTok, MU_Other)) return true; diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp index 43d31d6c5732..f6ca04defeb9 100644 --- a/clang/lib/Lex/PPMacroExpansion.cpp +++ b/clang/lib/Lex/PPMacroExpansion.cpp @@ -323,13 +323,16 @@ void Preprocessor::dumpMacroInfo(const IdentifierInfo *II) { /// RegisterBuiltinMacro - Register the specified identifier in the identifier /// table and mark it as a builtin macro to be expanded. -static IdentifierInfo *RegisterBuiltinMacro(Preprocessor &PP, const char *Name){ +static IdentifierInfo *RegisterBuiltinMacro(Preprocessor &PP, const char *Name, + bool Disabled = false) { // Get the identifier. IdentifierInfo *Id = PP.getIdentifierInfo(Name); // Mark it as being a macro that is builtin. MacroInfo *MI = PP.AllocateMacroInfo(SourceLocation()); MI->setIsBuiltinMacro(); + if (Disabled) + MI->DisableMacro(); PP.appendDefMacroDirective(Id, MI); return Id; } @@ -343,6 +346,7 @@ void Preprocessor::RegisterBuiltinMacros() { Ident__TIME__ = RegisterBuiltinMacro(*this, "__TIME__"); Ident__COUNTER__ = RegisterBuiltinMacro(*this, "__COUNTER__"); Ident_Pragma = RegisterBuiltinMacro(*this, "_Pragma"); + Ident__VA_OPT__ = RegisterBuiltinMacro(*this, "__VA_OPT__", true); // C++ Standing Document Extensions. if (getLangOpts().CPlusPlus) diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp index 94f1ce91f884..9baba204b324 100644 --- a/clang/lib/Lex/Preprocessor.cpp +++ b/clang/lib/Lex/Preprocessor.cpp @@ -115,23 +115,20 @@ Preprocessor::Preprocessor(std::shared_ptr<PreprocessorOptions> PPOpts, BuiltinInfo = std::make_unique<Builtin::Context>(); - // "Poison" __VA_ARGS__, __VA_OPT__ which can only appear in the expansion of - // a macro. They get unpoisoned where it is allowed. - (Ident__VA_ARGS__ = getIdentifierInfo("__VA_ARGS__"))->setIsPoisoned(); - SetPoisonReason(Ident__VA_ARGS__,diag::ext_pp_bad_vaargs_use); - if (getLangOpts().CPlusPlus20) { - (Ident__VA_OPT__ = getIdentifierInfo("__VA_OPT__"))->setIsPoisoned(); - SetPoisonReason(Ident__VA_OPT__,diag::ext_pp_bad_vaopt_use); - } else { - Ident__VA_OPT__ = nullptr; - } - // Initialize the pragma handlers. RegisterBuiltinPragmas(); // Initialize builtin macros like __LINE__ and friends. RegisterBuiltinMacros(); + // "Poison" __VA_ARGS__, __VA_OPT__ which can only appear in the expansion of + // a macro. They get unpoisoned where it is allowed. Note that we model + // __VA_OPT__ as a builtin macro to allow #ifdef and friends to detect it. + (Ident__VA_ARGS__ = getIdentifierInfo("__VA_ARGS__"))->setIsPoisoned(); + SetPoisonReason(Ident__VA_ARGS__, diag::ext_pp_bad_vaargs_use); + Ident__VA_OPT__->setIsPoisoned(); + SetPoisonReason(Ident__VA_OPT__, diag::ext_pp_bad_vaopt_use); + if(LangOpts.Borland) { Ident__exception_info = getIdentifierInfo("_exception_info"); Ident___exception_info = getIdentifierInfo("__exception_info"); diff --git a/clang/test/Preprocessor/macro_vaopt_check.cpp b/clang/test/Preprocessor/macro_vaopt_check.cpp index fb52e9946af3..84f3b85871dd 100644 --- a/clang/test/Preprocessor/macro_vaopt_check.cpp +++ b/clang/test/Preprocessor/macro_vaopt_check.cpp @@ -1,4 +1,20 @@ -// RUN: %clang_cc1 %s -Eonly -verify -Wno-all -pedantic -std=c++2a +// RUN: %clang_cc1 %s -Eonly -verify -Wno-all -pedantic -std=c++20 +// RUN: %clang_cc1 %s -Eonly -verify -Wno-all -pedantic -std=c++11 +// RUN: %clang_cc1 -x c %s -Eonly -verify -Wno-all -pedantic -std=c99 + +// Check that support for __VA_OPT__ can be detected by #ifdef. +#ifndef __VA_OPT__ +#error should be defined +#endif + +#ifdef __VA_OPT__ +#else +#error should be defined +#endif + +#if !defined(__VA_OPT__) +#error should be defined +#endif //expected-error@+1{{missing '('}} #define V1(...) __VA_OPT__ @@ -62,3 +78,16 @@ #define V1(...) __VA_OPT__ ((()) #undef V1 +// __VA_OPT__ can't appear anywhere else. +#if __VA_OPT__ // expected-warning {{__VA_OPT__ can only appear in the expansion of a variadic macro}} +#endif + +#define BAD __VA_OPT__ // expected-warning {{__VA_OPT__ can only appear in the expansion of a variadic macro}} + +// Check defined(__VA_OPT__) doesn't leave __VA_OPT__ poisoned. +#define Z(...) (0 __VA_OPT__(|| 1)) +#if defined(__VA_OPT__) && Z(hello) +// OK +#else +#error bad +#endif diff --git a/clang/test/Preprocessor/macro_vaopt_expand.cpp b/clang/test/Preprocessor/macro_vaopt_expand.cpp index 7ec4f6128cfa..5eb0facb83f7 100644 --- a/clang/test/Preprocessor/macro_vaopt_expand.cpp +++ b/clang/test/Preprocessor/macro_vaopt_expand.cpp @@ -1,4 +1,6 @@ -// RUN: %clang_cc1 -E %s -pedantic -std=c++2a | FileCheck -strict-whitespace %s +// RUN: %clang_cc1 -E %s -pedantic -std=c++20 | FileCheck -strict-whitespace %s +// RUN: %clang_cc1 -E %s -pedantic -std=c++11 | FileCheck -strict-whitespace %s +// RUN: %clang_cc1 -E -x c %s -pedantic -std=c99 | FileCheck -strict-whitespace %s #define LPAREN ( #define RPAREN ) _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
