//===--- Parser.cpp - C Language Family Parser ----------------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements the Parser interfaces. // //===----------------------------------------------------------------------===// #include "clang/Parse/Parser.h" #include "clang/Parse/ParseDiagnostic.h" #include "clang/Parse/DeclSpec.h" #include "clang/Parse/Scope.h" #include "clang/Parse/Template.h" #include "llvm/Support/raw_ostream.h" #include "RAIIObjectsForParser.h" #include "ParsePragma.h" using namespace clang; Parser::Parser(Preprocessor &pp, Action &actions) : CrashInfo(*this), PP(pp), Actions(actions), Diags(PP.getDiagnostics()), GreaterThanIsOperator(true), ColonIsSacred(false), TemplateParameterDepth(0) { Tok.setKind(tok::eof); CurScope = 0; NumCachedScopes = 0; ParenCount = BracketCount = BraceCount = 0; ObjCImpDecl = DeclPtrTy(); // Add #pragma handlers. These are removed and destroyed in the // destructor. OptionsHandler.reset(new PragmaOptionsHandler(&PP.getIdentifierTable().get("options"), actions)); PP.AddPragmaHandler(0, OptionsHandler.get()); PackHandler.reset(new PragmaPackHandler(&PP.getIdentifierTable().get("pack"), actions)); PP.AddPragmaHandler(0, PackHandler.get()); UnusedHandler.reset(new PragmaUnusedHandler(&PP.getIdentifierTable().get("unused"), actions, *this)); PP.AddPragmaHandler(0, UnusedHandler.get()); WeakHandler.reset(new PragmaWeakHandler(&PP.getIdentifierTable().get("weak"), actions)); PP.AddPragmaHandler(0, WeakHandler.get()); } /// If a crash happens while the parser is active, print out a line indicating /// what the current token is. void PrettyStackTraceParserEntry::print(llvm::raw_ostream &OS) const { const Token &Tok = P.getCurToken(); if (Tok.is(tok::eof)) { OS << " parser at end of file\n"; return; } if (Tok.getLocation().isInvalid()) { OS << " parser at unknown location\n"; return; } const Preprocessor &PP = P.getPreprocessor(); Tok.getLocation().print(OS, PP.getSourceManager()); if (Tok.isAnnotation()) OS << ": at annotation token \n"; else OS << ": current parser token '" << PP.getSpelling(Tok) << "'\n"; } DiagnosticBuilder Parser::Diag(SourceLocation Loc, unsigned DiagID) { return Diags.Report(FullSourceLoc(Loc, PP.getSourceManager()), DiagID); } DiagnosticBuilder Parser::Diag(const Token &Tok, unsigned DiagID) { return Diag(Tok.getLocation(), DiagID); } /// \brief Emits a diagnostic suggesting parentheses surrounding a /// given range. /// /// \param Loc The location where we'll emit the diagnostic. /// \param Loc The kind of diagnostic to emit. /// \param ParenRange Source range enclosing code that should be parenthesized. void Parser::SuggestParentheses(SourceLocation Loc, unsigned DK, SourceRange ParenRange) { SourceLocation EndLoc = PP.getLocForEndOfToken(ParenRange.getEnd()); if (!ParenRange.getEnd().isFileID() || EndLoc.isInvalid()) { // We can't display the parentheses, so just dig the // warning/error and return. Diag(Loc, DK); return; } Diag(Loc, DK) << FixItHint::CreateInsertion(ParenRange.getBegin(), "(") << FixItHint::CreateInsertion(EndLoc, ")"); } /// MatchRHSPunctuation - For punctuation with a LHS and RHS (e.g. '['/']'), /// this helper function matches and consumes the specified RHS token if /// present. If not present, it emits the specified diagnostic indicating /// that the parser failed to match the RHS of the token at LHSLoc. LHSName /// should be the name of the unmatched LHS token. SourceLocation Parser::MatchRHSPunctuation(tok::TokenKind RHSTok, SourceLocation LHSLoc) { if (Tok.is(RHSTok)) return ConsumeAnyToken(); SourceLocation R = Tok.getLocation(); const char *LHSName = "unknown"; diag::kind DID = diag::err_parse_error; switch (RHSTok) { default: break; case tok::r_paren : LHSName = "("; DID = diag::err_expected_rparen; break; case tok::r_brace : LHSName = "{"; DID = diag::err_expected_rbrace; break; case tok::r_square: LHSName = "["; DID = diag::err_expected_rsquare; break; case tok::greater: LHSName = "<"; DID = diag::err_expected_greater; break; } Diag(Tok, DID); Diag(LHSLoc, diag::note_matching) << LHSName; SkipUntil(RHSTok); return R; } /// ExpectAndConsume - The parser expects that 'ExpectedTok' is next in the /// input. If so, it is consumed and false is returned. /// /// If the input is malformed, this emits the specified diagnostic. Next, if /// SkipToTok is specified, it calls SkipUntil(SkipToTok). Finally, true is /// returned. bool Parser::ExpectAndConsume(tok::TokenKind ExpectedTok, unsigned DiagID, const char *Msg, tok::TokenKind SkipToTok) { if (Tok.is(ExpectedTok) || Tok.is(tok::code_completion)) { ConsumeAnyToken(); return false; } const char *Spelling = 0; SourceLocation EndLoc = PP.getLocForEndOfToken(PrevTokLocation); if (EndLoc.isValid() && (Spelling = tok::getTokenSimpleSpelling(ExpectedTok))) { // Show what code to insert to fix this problem. Diag(EndLoc, DiagID) << Msg << FixItHint::CreateInsertion(EndLoc, Spelling); } else Diag(Tok, DiagID) << Msg; if (SkipToTok != tok::unknown) SkipUntil(SkipToTok); return true; } //===----------------------------------------------------------------------===// // Error recovery. //===----------------------------------------------------------------------===// /// SkipUntil - Read tokens until we get to the specified token, then consume /// it (unless DontConsume is true). Because we cannot guarantee that the /// token will ever occur, this skips to the next token, or to some likely /// good stopping point. If StopAtSemi is true, skipping will stop at a ';' /// character. /// /// If SkipUntil finds the specified token, it returns true, otherwise it /// returns false. bool Parser::SkipUntil(const tok::TokenKind *Toks, unsigned NumToks, bool StopAtSemi, bool DontConsume) { // We always want this function to skip at least one token if the first token // isn't T and if not at EOF. bool isFirstTokenSkipped = true; while (1) { // If we found one of the tokens, stop and return true. for (unsigned i = 0; i != NumToks; ++i) { if (Tok.is(Toks[i])) { if (DontConsume) { // Noop, don't consume the token. } else { ConsumeAnyToken(); } return true; } } switch (Tok.getKind()) { case tok::eof: // Ran out of tokens. return false; case tok::code_completion: ConsumeToken(); return false; case tok::l_paren: // Recursively skip properly-nested parens. ConsumeParen(); SkipUntil(tok::r_paren, false); break; case tok::l_square: // Recursively skip properly-nested square brackets. ConsumeBracket(); SkipUntil(tok::r_square, false); break; case tok::l_brace: // Recursively skip properly-nested braces. ConsumeBrace(); SkipUntil(tok::r_brace, false); break; // Okay, we found a ']' or '}' or ')', which we think should be balanced. // Since the user wasn't looking for this token (if they were, it would // already be handled), this isn't balanced. If there is a LHS token at a // higher level, we will assume that this matches the unbalanced token // and return it. Otherwise, this is a spurious RHS token, which we skip. case tok::r_paren: if (ParenCount && !isFirstTokenSkipped) return false; // Matches something. ConsumeParen(); break; case tok::r_square: if (BracketCount && !isFirstTokenSkipped) return false; // Matches something. ConsumeBracket(); break; case tok::r_brace: if (BraceCount && !isFirstTokenSkipped) return false; // Matches something. ConsumeBrace(); break; case tok::string_literal: case tok::wide_string_literal: ConsumeStringToken(); break; case tok::semi: if (StopAtSemi) return false; // FALL THROUGH. default: // Skip this token. ConsumeToken(); break; } isFirstTokenSkipped = false; } } //===----------------------------------------------------------------------===// // Scope manipulation //===----------------------------------------------------------------------===// /// EnterScope - Start a new scope. void Parser::EnterScope(unsigned ScopeFlags) { if (NumCachedScopes) { Scope *N = ScopeCache[--NumCachedScopes]; N->Init(CurScope, ScopeFlags); CurScope = N; } else { CurScope = new Scope(CurScope, ScopeFlags); } CurScope->setNumErrorsAtStart(Diags.getNumErrors()); } /// ExitScope - Pop a scope off the scope stack. void Parser::ExitScope() { assert(CurScope && "Scope imbalance!"); // Inform the actions module that this scope is going away if there are any // decls in it. if (!CurScope->decl_empty()) Actions.ActOnPopScope(Tok.getLocation(), CurScope); Scope *OldScope = CurScope; CurScope = OldScope->getParent(); if (NumCachedScopes == ScopeCacheSize) delete OldScope; else ScopeCache[NumCachedScopes++] = OldScope; } //===----------------------------------------------------------------------===// // C99 6.9: External Definitions. //===----------------------------------------------------------------------===// Parser::~Parser() { // If we still have scopes active, delete the scope tree. delete CurScope; // Free the scope cache. for (unsigned i = 0, e = NumCachedScopes; i != e; ++i) delete ScopeCache[i]; // Remove the pragma handlers we installed. PP.RemovePragmaHandler(0, OptionsHandler.get()); OptionsHandler.reset(); PP.RemovePragmaHandler(0, PackHandler.get()); PackHandler.reset(); PP.RemovePragmaHandler(0, UnusedHandler.get()); UnusedHandler.reset(); PP.RemovePragmaHandler(0, WeakHandler.get()); WeakHandler.reset(); } /// Initialize - Warm up the parser. /// void Parser::Initialize() { // Prime the lexer look-ahead. ConsumeToken(); // Create the translation unit scope. Install it as the current scope. assert(CurScope == 0 && "A scope is already active?"); EnterScope(Scope::DeclScope); Actions.ActOnTranslationUnitScope(Tok.getLocation(), CurScope); if (Tok.is(tok::eof) && !getLang().CPlusPlus) // Empty source file is an extension in C Diag(Tok, diag::ext_empty_source_file); // Initialization for Objective-C context sensitive keywords recognition. // Referenced in Parser::ParseObjCTypeQualifierList. if (getLang().ObjC1) { ObjCTypeQuals[objc_in] = &PP.getIdentifierTable().get("in"); ObjCTypeQuals[objc_out] = &PP.getIdentifierTable().get("out"); ObjCTypeQuals[objc_inout] = &PP.getIdentifierTable().get("inout"); ObjCTypeQuals[objc_oneway] = &PP.getIdentifierTable().get("oneway"); ObjCTypeQuals[objc_bycopy] = &PP.getIdentifierTable().get("bycopy"); ObjCTypeQuals[objc_byref] = &PP.getIdentifierTable().get("byref"); } Ident_super = &PP.getIdentifierTable().get("super"); if (getLang().AltiVec) { Ident_vector = &PP.getIdentifierTable().get("vector"); Ident_pixel = &PP.getIdentifierTable().get("pixel"); } } /// ParseTopLevelDecl - Parse one top-level declaration, return whatever the /// action tells us to. This returns true if the EOF was encountered. bool Parser::ParseTopLevelDecl(DeclGroupPtrTy &Result) { Result = DeclGroupPtrTy(); if (Tok.is(tok::eof)) { Actions.ActOnEndOfTranslationUnit(); return true; } CXX0XAttributeList Attr; if (getLang().CPlusPlus0x && isCXX0XAttributeSpecifier()) Attr = ParseCXX0XAttributes(); Result = ParseExternalDeclaration(Attr); return false; } /// ParseTranslationUnit: /// translation-unit: [C99 6.9] /// external-declaration /// translation-unit external-declaration void Parser::ParseTranslationUnit() { Initialize(); DeclGroupPtrTy Res; while (!ParseTopLevelDecl(Res)) /*parse them all*/; ExitScope(); assert(CurScope == 0 && "Scope imbalance!"); } /// ParseExternalDeclaration: /// /// external-declaration: [C99 6.9], declaration: [C++ dcl.dcl] /// function-definition /// declaration /// [C++0x] empty-declaration /// [GNU] asm-definition /// [GNU] __extension__ external-declaration /// [OBJC] objc-class-definition /// [OBJC] objc-class-declaration /// [OBJC] objc-alias-declaration /// [OBJC] objc-protocol-definition /// [OBJC] objc-method-definition /// [OBJC] @end /// [C++] linkage-specification /// [GNU] asm-definition: /// simple-asm-expr ';' /// /// [C++0x] empty-declaration: /// ';' /// /// [C++0x/GNU] 'extern' 'template' declaration Parser::DeclGroupPtrTy Parser::ParseExternalDeclaration(CXX0XAttributeList Attr) { DeclPtrTy SingleDecl; switch (Tok.getKind()) { case tok::semi: if (!getLang().CPlusPlus0x) Diag(Tok, diag::ext_top_level_semi) << FixItHint::CreateRemoval(Tok.getLocation()); ConsumeToken(); // TODO: Invoke action for top-level semicolon. return DeclGroupPtrTy(); case tok::r_brace: Diag(Tok, diag::err_expected_external_declaration); ConsumeBrace(); return DeclGroupPtrTy(); case tok::eof: Diag(Tok, diag::err_expected_external_declaration); return DeclGroupPtrTy(); case tok::kw___extension__: { // __extension__ silences extension warnings in the subexpression. ExtensionRAIIObject O(Diags); // Use RAII to do this. ConsumeToken(); return ParseExternalDeclaration(Attr); } case tok::kw_asm: { if (Attr.HasAttr) Diag(Attr.Range.getBegin(), diag::err_attributes_not_allowed) << Attr.Range; OwningExprResult Result(ParseSimpleAsm()); ExpectAndConsume(tok::semi, diag::err_expected_semi_after, "top-level asm block"); if (Result.isInvalid()) return DeclGroupPtrTy(); SingleDecl = Actions.ActOnFileScopeAsmDecl(Tok.getLocation(), move(Result)); break; } case tok::at: // @ is not a legal token unless objc is enabled, no need to check for ObjC. /// FIXME: ParseObjCAtDirectives should return a DeclGroup for things like /// @class foo, bar; SingleDecl = ParseObjCAtDirectives(); break; case tok::minus: case tok::plus: if (!getLang().ObjC1) { Diag(Tok, diag::err_expected_external_declaration); ConsumeToken(); return DeclGroupPtrTy(); } SingleDecl = ParseObjCMethodDefinition(); break; case tok::code_completion: Actions.CodeCompleteOrdinaryName(CurScope, ObjCImpDecl? Action::CCC_ObjCImplementation : Action::CCC_Namespace); ConsumeCodeCompletionToken(); return ParseExternalDeclaration(Attr); case tok::kw_using: case tok::kw_namespace: case tok::kw_typedef: case tok::kw_template: case tok::kw_export: // As in 'export template' case tok::kw_static_assert: // A function definition cannot start with a these keywords. { SourceLocation DeclEnd; return ParseDeclaration(Declarator::FileContext, DeclEnd, Attr); } case tok::kw_extern: if (getLang().CPlusPlus && NextToken().is(tok::kw_template)) { // Extern templates SourceLocation ExternLoc = ConsumeToken(); SourceLocation TemplateLoc = ConsumeToken(); SourceLocation DeclEnd; return Actions.ConvertDeclToDeclGroup( ParseExplicitInstantiation(ExternLoc, TemplateLoc, DeclEnd)); } // FIXME: Detect C++ linkage specifications here? // Fall through to handle other declarations or function definitions. default: // We can't tell whether this is a function-definition or declaration yet. return ParseDeclarationOrFunctionDefinition(Attr.AttrList); } // This routine returns a DeclGroup, if the thing we parsed only contains a // single decl, convert it now. return Actions.ConvertDeclToDeclGroup(SingleDecl); } /// \brief Determine whether the current token, if it occurs after a /// declarator, continues a declaration or declaration list. bool Parser::isDeclarationAfterDeclarator() { return Tok.is(tok::equal) || // int X()= -> not a function def Tok.is(tok::comma) || // int X(), -> not a function def Tok.is(tok::semi) || // int X(); -> not a function def Tok.is(tok::kw_asm) || // int X() __asm__ -> not a function def Tok.is(tok::kw___attribute) || // int X() __attr__ -> not a function def (getLang().CPlusPlus && Tok.is(tok::l_paren)); // int X(0) -> not a function def [C++] } /// \brief Determine whether the current token, if it occurs after a /// declarator, indicates the start of a function definition. bool Parser::isStartOfFunctionDefinition() { if (Tok.is(tok::l_brace)) // int X() {} return true; if (!getLang().CPlusPlus) return isDeclarationSpecifier(); // int X(f) int f; {} return Tok.is(tok::colon) || // X() : Base() {} (used for ctors) Tok.is(tok::kw_try); // X() try { ... } } /// ParseDeclarationOrFunctionDefinition - Parse either a function-definition or /// a declaration. We can't tell which we have until we read up to the /// compound-statement in function-definition. TemplateParams, if /// non-NULL, provides the template parameters when we're parsing a /// C++ template-declaration. /// /// function-definition: [C99 6.9.1] /// decl-specs declarator declaration-list[opt] compound-statement /// [C90] function-definition: [C99 6.7.1] - implicit int result /// [C90] decl-specs[opt] declarator declaration-list[opt] compound-statement /// /// declaration: [C99 6.7] /// declaration-specifiers init-declarator-list[opt] ';' /// [!C99] init-declarator-list ';' [TODO: warn in c99 mode] /// [OMP] threadprivate-directive [TODO] /// Parser::DeclGroupPtrTy Parser::ParseDeclarationOrFunctionDefinition(ParsingDeclSpec &DS, AttributeList *Attr, AccessSpecifier AS) { // Parse the common declaration-specifiers piece. if (Attr) DS.AddAttributes(Attr); ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS, DSC_top_level); // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };" // declaration-specifiers init-declarator-list[opt] ';' if (Tok.is(tok::semi)) { ConsumeToken(); DeclPtrTy TheDecl = Actions.ParsedFreeStandingDeclSpec(CurScope, AS, DS); DS.complete(TheDecl); return Actions.ConvertDeclToDeclGroup(TheDecl); } // ObjC2 allows prefix attributes on class interfaces and protocols. // FIXME: This still needs better diagnostics. We should only accept // attributes here, no types, etc. if (getLang().ObjC2 && Tok.is(tok::at)) { SourceLocation AtLoc = ConsumeToken(); // the "@" if (!Tok.isObjCAtKeyword(tok::objc_interface) && !Tok.isObjCAtKeyword(tok::objc_protocol)) { Diag(Tok, diag::err_objc_unexpected_attr); SkipUntil(tok::semi); // FIXME: better skip? return DeclGroupPtrTy(); } DS.abort(); const char *PrevSpec = 0; unsigned DiagID; if (DS.SetTypeSpecType(DeclSpec::TST_unspecified, AtLoc, PrevSpec, DiagID)) Diag(AtLoc, DiagID) << PrevSpec; DeclPtrTy TheDecl; if (Tok.isObjCAtKeyword(tok::objc_protocol)) TheDecl = ParseObjCAtProtocolDeclaration(AtLoc, DS.getAttributes()); else TheDecl = ParseObjCAtInterfaceDeclaration(AtLoc, DS.getAttributes()); return Actions.ConvertDeclToDeclGroup(TheDecl); } // If the declspec consisted only of 'extern' and we have a string // literal following it, this must be a C++ linkage specifier like // 'extern "C"'. if (Tok.is(tok::string_literal) && getLang().CPlusPlus && DS.getStorageClassSpec() == DeclSpec::SCS_extern && DS.getParsedSpecifiers() == DeclSpec::PQ_StorageClassSpecifier) { DeclPtrTy TheDecl = ParseLinkage(DS, Declarator::FileContext); return Actions.ConvertDeclToDeclGroup(TheDecl); } return ParseDeclGroup(DS, Declarator::FileContext, true); } Parser::DeclGroupPtrTy Parser::ParseDeclarationOrFunctionDefinition(AttributeList *Attr, AccessSpecifier AS) { ParsingDeclSpec DS(*this); return ParseDeclarationOrFunctionDefinition(DS, Attr, AS); } /// ParseFunctionDefinition - We parsed and verified that the specified /// Declarator is well formed. If this is a K&R-style function, read the /// parameters declaration-list, then start the compound-statement. /// /// function-definition: [C99 6.9.1] /// decl-specs declarator declaration-list[opt] compound-statement /// [C90] function-definition: [C99 6.7.1] - implicit int result /// [C90] decl-specs[opt] declarator declaration-list[opt] compound-statement /// [C++] function-definition: [C++ 8.4] /// decl-specifier-seq[opt] declarator ctor-initializer[opt] /// function-body /// [C++] function-definition: [C++ 8.4] /// decl-specifier-seq[opt] declarator function-try-block /// Parser::DeclPtrTy Parser::ParseFunctionDefinition(ParsingDeclarator &D, const ParsedTemplateInfo &TemplateInfo) { const DeclaratorChunk &FnTypeInfo = D.getTypeObject(0); assert(FnTypeInfo.Kind == DeclaratorChunk::Function && "This isn't a function declarator!"); const DeclaratorChunk::FunctionTypeInfo &FTI = FnTypeInfo.Fun; // If this is C90 and the declspecs were completely missing, fudge in an // implicit int. We do this here because this is the only place where // declaration-specifiers are completely optional in the grammar. if (getLang().ImplicitInt && D.getDeclSpec().isEmpty()) { const char *PrevSpec; unsigned DiagID; D.getMutableDeclSpec().SetTypeSpecType(DeclSpec::TST_int, D.getIdentifierLoc(), PrevSpec, DiagID); D.SetRangeBegin(D.getDeclSpec().getSourceRange().getBegin()); } // If this declaration was formed with a K&R-style identifier list for the // arguments, parse declarations for all of the args next. // int foo(a,b) int a; float b; {} if (!FTI.hasPrototype && FTI.NumArgs != 0) ParseKNRParamDeclarations(D); // We should have either an opening brace or, in a C++ constructor, // we may have a colon. if (Tok.isNot(tok::l_brace) && Tok.isNot(tok::colon) && Tok.isNot(tok::kw_try)) { Diag(Tok, diag::err_expected_fn_body); // Skip over garbage, until we get to '{'. Don't eat the '{'. SkipUntil(tok::l_brace, true, true); // If we didn't find the '{', bail out. if (Tok.isNot(tok::l_brace)) return DeclPtrTy(); } // Enter a scope for the function body. ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope); // Tell the actions module that we have entered a function definition with the // specified Declarator for the function. DeclPtrTy Res = TemplateInfo.TemplateParams? Actions.ActOnStartOfFunctionTemplateDef(CurScope, Action::MultiTemplateParamsArg(Actions, TemplateInfo.TemplateParams->data(), TemplateInfo.TemplateParams->size()), D) : Actions.ActOnStartOfFunctionDef(CurScope, D); // Break out of the ParsingDeclarator context before we parse the body. D.complete(Res); // Break out of the ParsingDeclSpec context, too. This const_cast is // safe because we're always the sole owner. D.getMutableDeclSpec().abort(); if (Tok.is(tok::kw_try)) return ParseFunctionTryBlock(Res); // If we have a colon, then we're probably parsing a C++ // ctor-initializer. if (Tok.is(tok::colon)) { ParseConstructorInitializer(Res); // Recover from error. if (!Tok.is(tok::l_brace)) { Actions.ActOnFinishFunctionBody(Res, Action::StmtArg(Actions)); return Res; } } else Actions.ActOnDefaultCtorInitializers(Res); return ParseFunctionStatementBody(Res); } /// ParseKNRParamDeclarations - Parse 'declaration-list[opt]' which provides /// types for a function with a K&R-style identifier list for arguments. void Parser::ParseKNRParamDeclarations(Declarator &D) { // We know that the top-level of this declarator is a function. DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; // Enter function-declaration scope, limiting any declarators to the // function prototype scope, including parameter declarators. ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope|Scope::DeclScope); // Read all the argument declarations. while (isDeclarationSpecifier()) { SourceLocation DSStart = Tok.getLocation(); // Parse the common declaration-specifiers piece. DeclSpec DS; ParseDeclarationSpecifiers(DS); // C99 6.9.1p6: 'each declaration in the declaration list shall have at // least one declarator'. // NOTE: GCC just makes this an ext-warn. It's not clear what it does with // the declarations though. It's trivial to ignore them, really hard to do // anything else with them. if (Tok.is(tok::semi)) { Diag(DSStart, diag::err_declaration_does_not_declare_param); ConsumeToken(); continue; } // C99 6.9.1p6: Declarations shall contain no storage-class specifiers other // than register. if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && DS.getStorageClassSpec() != DeclSpec::SCS_register) { Diag(DS.getStorageClassSpecLoc(), diag::err_invalid_storage_class_in_func_decl); DS.ClearStorageClassSpecs(); } if (DS.isThreadSpecified()) { Diag(DS.getThreadSpecLoc(), diag::err_invalid_storage_class_in_func_decl); DS.ClearStorageClassSpecs(); } // Parse the first declarator attached to this declspec. Declarator ParmDeclarator(DS, Declarator::KNRTypeListContext); ParseDeclarator(ParmDeclarator); // Handle the full declarator list. while (1) { // If attributes are present, parse them. if (Tok.is(tok::kw___attribute)) { SourceLocation Loc; AttributeList *AttrList = ParseGNUAttributes(&Loc); ParmDeclarator.AddAttributes(AttrList, Loc); } // Ask the actions module to compute the type for this declarator. Action::DeclPtrTy Param = Actions.ActOnParamDeclarator(CurScope, ParmDeclarator); if (Param && // A missing identifier has already been diagnosed. ParmDeclarator.getIdentifier()) { // Scan the argument list looking for the correct param to apply this // type. for (unsigned i = 0; ; ++i) { // C99 6.9.1p6: those declarators shall declare only identifiers from // the identifier list. if (i == FTI.NumArgs) { Diag(ParmDeclarator.getIdentifierLoc(), diag::err_no_matching_param) << ParmDeclarator.getIdentifier(); break; } if (FTI.ArgInfo[i].Ident == ParmDeclarator.getIdentifier()) { // Reject redefinitions of parameters. if (FTI.ArgInfo[i].Param) { Diag(ParmDeclarator.getIdentifierLoc(), diag::err_param_redefinition) << ParmDeclarator.getIdentifier(); } else { FTI.ArgInfo[i].Param = Param; } break; } } } // If we don't have a comma, it is either the end of the list (a ';') or // an error, bail out. if (Tok.isNot(tok::comma)) break; // Consume the comma. ConsumeToken(); // Parse the next declarator. ParmDeclarator.clear(); ParseDeclarator(ParmDeclarator); } if (Tok.is(tok::semi)) { ConsumeToken(); } else { Diag(Tok, diag::err_parse_error); // Skip to end of block or statement SkipUntil(tok::semi, true); if (Tok.is(tok::semi)) ConsumeToken(); } } // The actions module must verify that all arguments were declared. Actions.ActOnFinishKNRParamDeclarations(CurScope, D, Tok.getLocation()); } /// ParseAsmStringLiteral - This is just a normal string-literal, but is not /// allowed to be a wide string, and is not subject to character translation. /// /// [GNU] asm-string-literal: /// string-literal /// Parser::OwningExprResult Parser::ParseAsmStringLiteral() { if (!isTokenStringLiteral()) { Diag(Tok, diag::err_expected_string_literal); return ExprError(); } OwningExprResult Res(ParseStringLiteralExpression()); if (Res.isInvalid()) return move(Res); // TODO: Diagnose: wide string literal in 'asm' return move(Res); } /// ParseSimpleAsm /// /// [GNU] simple-asm-expr: /// 'asm' '(' asm-string-literal ')' /// Parser::OwningExprResult Parser::ParseSimpleAsm(SourceLocation *EndLoc) { assert(Tok.is(tok::kw_asm) && "Not an asm!"); SourceLocation Loc = ConsumeToken(); if (Tok.is(tok::kw_volatile)) { // Remove from the end of 'asm' to the end of 'volatile'. SourceRange RemovalRange(PP.getLocForEndOfToken(Loc), PP.getLocForEndOfToken(Tok.getLocation())); Diag(Tok, diag::warn_file_asm_volatile) << FixItHint::CreateRemoval(RemovalRange); ConsumeToken(); } if (Tok.isNot(tok::l_paren)) { Diag(Tok, diag::err_expected_lparen_after) << "asm"; return ExprError(); } Loc = ConsumeParen(); OwningExprResult Result(ParseAsmStringLiteral()); if (Result.isInvalid()) { SkipUntil(tok::r_paren, true, true); if (EndLoc) *EndLoc = Tok.getLocation(); ConsumeAnyToken(); } else { Loc = MatchRHSPunctuation(tok::r_paren, Loc); if (EndLoc) *EndLoc = Loc; } return move(Result); } /// TryAnnotateTypeOrScopeToken - If the current token position is on a /// typename (possibly qualified in C++) or a C++ scope specifier not followed /// by a typename, TryAnnotateTypeOrScopeToken will replace one or more tokens /// with a single annotation token representing the typename or C++ scope /// respectively. /// This simplifies handling of C++ scope specifiers and allows efficient /// backtracking without the need to re-parse and resolve nested-names and /// typenames. /// It will mainly be called when we expect to treat identifiers as typenames /// (if they are typenames). For example, in C we do not expect identifiers /// inside expressions to be treated as typenames so it will not be called /// for expressions in C. /// The benefit for C/ObjC is that a typename will be annotated and /// Actions.getTypeName will not be needed to be called again (e.g. getTypeName /// will not be called twice, once to check whether we have a declaration /// specifier, and another one to get the actual type inside /// ParseDeclarationSpecifiers). /// /// This returns true if an error occurred. /// /// Note that this routine emits an error if you call it with ::new or ::delete /// as the current tokens, so only call it in contexts where these are invalid. bool Parser::TryAnnotateTypeOrScopeToken(bool EnteringContext) { assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon) || Tok.is(tok::kw_typename) || Tok.is(tok::annot_cxxscope)) && "Cannot be a type or scope token!"); if (Tok.is(tok::kw_typename)) { // Parse a C++ typename-specifier, e.g., "typename T::type". // // typename-specifier: // 'typename' '::' [opt] nested-name-specifier identifier // 'typename' '::' [opt] nested-name-specifier template [opt] // simple-template-id SourceLocation TypenameLoc = ConsumeToken(); CXXScopeSpec SS; if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/0, false)) return true; if (!SS.isSet()) { Diag(Tok.getLocation(), diag::err_expected_qualified_after_typename); return true; } TypeResult Ty; if (Tok.is(tok::identifier)) { // FIXME: check whether the next token is '<', first! Ty = Actions.ActOnTypenameType(TypenameLoc, SS, *Tok.getIdentifierInfo(), Tok.getLocation()); } else if (Tok.is(tok::annot_template_id)) { TemplateIdAnnotation *TemplateId = static_cast(Tok.getAnnotationValue()); if (TemplateId->Kind == TNK_Function_template) { Diag(Tok, diag::err_typename_refers_to_non_type_template) << Tok.getAnnotationRange(); return true; } AnnotateTemplateIdTokenAsType(0); assert(Tok.is(tok::annot_typename) && "AnnotateTemplateIdTokenAsType isn't working properly"); if (Tok.getAnnotationValue()) Ty = Actions.ActOnTypenameType(TypenameLoc, SS, SourceLocation(), Tok.getAnnotationValue()); else Ty = true; } else { Diag(Tok, diag::err_expected_type_name_after_typename) << SS.getRange(); return true; } SourceLocation EndLoc = Tok.getLastLoc(); Tok.setKind(tok::annot_typename); Tok.setAnnotationValue(Ty.isInvalid()? 0 : Ty.get()); Tok.setAnnotationEndLoc(EndLoc); Tok.setLocation(TypenameLoc); PP.AnnotateCachedTokens(Tok); return false; } // Remembers whether the token was originally a scope annotation. bool wasScopeAnnotation = Tok.is(tok::annot_cxxscope); CXXScopeSpec SS; if (getLang().CPlusPlus) if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/0, EnteringContext)) return true; if (Tok.is(tok::identifier)) { // Determine whether the identifier is a type name. if (TypeTy *Ty = Actions.getTypeName(*Tok.getIdentifierInfo(), Tok.getLocation(), CurScope, &SS)) { // This is a typename. Replace the current token in-place with an // annotation type token. Tok.setKind(tok::annot_typename); Tok.setAnnotationValue(Ty); Tok.setAnnotationEndLoc(Tok.getLocation()); if (SS.isNotEmpty()) // it was a C++ qualified type name. Tok.setLocation(SS.getBeginLoc()); // In case the tokens were cached, have Preprocessor replace // them with the annotation token. PP.AnnotateCachedTokens(Tok); return false; } if (!getLang().CPlusPlus) { // If we're in C, we can't have :: tokens at all (the lexer won't return // them). If the identifier is not a type, then it can't be scope either, // just early exit. return false; } // If this is a template-id, annotate with a template-id or type token. if (NextToken().is(tok::less)) { TemplateTy Template; UnqualifiedId TemplateName; TemplateName.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation()); bool MemberOfUnknownSpecialization; if (TemplateNameKind TNK = Actions.isTemplateName(CurScope, SS, TemplateName, /*ObjectType=*/0, EnteringContext, Template, MemberOfUnknownSpecialization)) { // Consume the identifier. ConsumeToken(); if (AnnotateTemplateIdToken(Template, TNK, &SS, TemplateName)) { // If an unrecoverable error occurred, we need to return true here, // because the token stream is in a damaged state. We may not return // a valid identifier. return true; } } } // The current token, which is either an identifier or a // template-id, is not part of the annotation. Fall through to // push that token back into the stream and complete the C++ scope // specifier annotation. } if (Tok.is(tok::annot_template_id)) { TemplateIdAnnotation *TemplateId = static_cast(Tok.getAnnotationValue()); if (TemplateId->Kind == TNK_Type_template) { // A template-id that refers to a type was parsed into a // template-id annotation in a context where we weren't allowed // to produce a type annotation token. Update the template-id // annotation token to a type annotation token now. AnnotateTemplateIdTokenAsType(&SS); return false; } } if (SS.isEmpty()) return false; // A C++ scope specifier that isn't followed by a typename. // Push the current token back into the token stream (or revert it if it is // cached) and use an annotation scope token for current token. if (PP.isBacktrackEnabled()) PP.RevertCachedTokens(1); else PP.EnterToken(Tok); Tok.setKind(tok::annot_cxxscope); Tok.setAnnotationValue(SS.getScopeRep()); Tok.setAnnotationRange(SS.getRange()); // In case the tokens were cached, have Preprocessor replace them // with the annotation token. We don't need to do this if we've // just reverted back to the state we were in before being called. if (!wasScopeAnnotation) PP.AnnotateCachedTokens(Tok); return false; } /// TryAnnotateScopeToken - Like TryAnnotateTypeOrScopeToken but only /// annotates C++ scope specifiers and template-ids. This returns /// true if the token was annotated or there was an error that could not be /// recovered from. /// /// Note that this routine emits an error if you call it with ::new or ::delete /// as the current tokens, so only call it in contexts where these are invalid. bool Parser::TryAnnotateCXXScopeToken(bool EnteringContext) { assert(getLang().CPlusPlus && "Call sites of this function should be guarded by checking for C++"); assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon)) && "Cannot be a type or scope token!"); CXXScopeSpec SS; if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/0, EnteringContext)) return true; if (SS.isEmpty()) return false; // Push the current token back into the token stream (or revert it if it is // cached) and use an annotation scope token for current token. if (PP.isBacktrackEnabled()) PP.RevertCachedTokens(1); else PP.EnterToken(Tok); Tok.setKind(tok::annot_cxxscope); Tok.setAnnotationValue(SS.getScopeRep()); Tok.setAnnotationRange(SS.getRange()); // In case the tokens were cached, have Preprocessor replace them with the // annotation token. PP.AnnotateCachedTokens(Tok); return false; } void Parser::CodeCompletionRecovery() { for (Scope *S = CurScope; S; S = S->getParent()) { if (S->getFlags() & Scope::FnScope) { Actions.CodeCompleteOrdinaryName(CurScope, Action::CCC_RecoveryInFunction); return; } if (S->getFlags() & Scope::ClassScope) { Actions.CodeCompleteOrdinaryName(CurScope, Action::CCC_Class); return; } } Actions.CodeCompleteOrdinaryName(CurScope, Action::CCC_Namespace); } // Anchor the Parser::FieldCallback vtable to this translation unit. // We use a spurious method instead of the destructor because // destroying FieldCallbacks can actually be slightly // performance-sensitive. void Parser::FieldCallback::_anchor() { }