//===--- ParseExprCXX.cpp - C++ Expression Parsing ------------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // // This file implements the Expression parsing implementation for C++. // //===----------------------------------------------------------------------===// #include "clang/Parse/Parser.h" #include "clang/AST/ASTContext.h" #include "clang/AST/Decl.h" #include "clang/AST/DeclTemplate.h" #include "clang/AST/ExprCXX.h" #include "clang/Basic/PrettyStackTrace.h" #include "clang/Lex/LiteralSupport.h" #include "clang/Parse/ParseDiagnostic.h" #include "clang/Parse/RAIIObjectsForParser.h" #include "clang/Sema/DeclSpec.h" #include "clang/Sema/ParsedTemplate.h" #include "clang/Sema/Scope.h" #include "llvm/Support/ErrorHandling.h" #include using namespace clang; static int SelectDigraphErrorMessage(tok::TokenKind Kind) { switch (Kind) { // template name case tok::unknown: return 0; // casts case tok::kw_addrspace_cast: return 1; case tok::kw_const_cast: return 2; case tok::kw_dynamic_cast: return 3; case tok::kw_reinterpret_cast: return 4; case tok::kw_static_cast: return 5; default: llvm_unreachable("Unknown type for digraph error message."); } } // Are the two tokens adjacent in the same source file? bool Parser::areTokensAdjacent(const Token &First, const Token &Second) { SourceManager &SM = PP.getSourceManager(); SourceLocation FirstLoc = SM.getSpellingLoc(First.getLocation()); SourceLocation FirstEnd = FirstLoc.getLocWithOffset(First.getLength()); return FirstEnd == SM.getSpellingLoc(Second.getLocation()); } // Suggest fixit for "<::" after a cast. static void FixDigraph(Parser &P, Preprocessor &PP, Token &DigraphToken, Token &ColonToken, tok::TokenKind Kind, bool AtDigraph) { // Pull '<:' and ':' off token stream. if (!AtDigraph) PP.Lex(DigraphToken); PP.Lex(ColonToken); SourceRange Range; Range.setBegin(DigraphToken.getLocation()); Range.setEnd(ColonToken.getLocation()); P.Diag(DigraphToken.getLocation(), diag::err_missing_whitespace_digraph) << SelectDigraphErrorMessage(Kind) << FixItHint::CreateReplacement(Range, "< ::"); // Update token information to reflect their change in token type. ColonToken.setKind(tok::coloncolon); ColonToken.setLocation(ColonToken.getLocation().getLocWithOffset(-1)); ColonToken.setLength(2); DigraphToken.setKind(tok::less); DigraphToken.setLength(1); // Push new tokens back to token stream. PP.EnterToken(ColonToken, /*IsReinject*/ true); if (!AtDigraph) PP.EnterToken(DigraphToken, /*IsReinject*/ true); } // Check for '<::' which should be '< ::' instead of '[:' when following // a template name. void Parser::CheckForTemplateAndDigraph(Token &Next, ParsedType ObjectType, bool EnteringContext, IdentifierInfo &II, CXXScopeSpec &SS) { if (!Next.is(tok::l_square) || Next.getLength() != 2) return; Token SecondToken = GetLookAheadToken(2); if (!SecondToken.is(tok::colon) || !areTokensAdjacent(Next, SecondToken)) return; TemplateTy Template; UnqualifiedId TemplateName; TemplateName.setIdentifier(&II, Tok.getLocation()); bool MemberOfUnknownSpecialization; if (!Actions.isTemplateName(getCurScope(), SS, /*hasTemplateKeyword=*/false, TemplateName, ObjectType, EnteringContext, Template, MemberOfUnknownSpecialization)) return; FixDigraph(*this, PP, Next, SecondToken, tok::unknown, /*AtDigraph*/false); } /// Parse global scope or nested-name-specifier if present. /// /// Parses a C++ global scope specifier ('::') or nested-name-specifier (which /// may be preceded by '::'). Note that this routine will not parse ::new or /// ::delete; it will just leave them in the token stream. /// /// '::'[opt] nested-name-specifier /// '::' /// /// nested-name-specifier: /// type-name '::' /// namespace-name '::' /// nested-name-specifier identifier '::' /// nested-name-specifier 'template'[opt] simple-template-id '::' /// /// /// \param SS the scope specifier that will be set to the parsed /// nested-name-specifier (or empty) /// /// \param ObjectType if this nested-name-specifier is being parsed following /// the "." or "->" of a member access expression, this parameter provides the /// type of the object whose members are being accessed. /// /// \param ObjectHadErrors if this unqualified-id occurs within a member access /// expression, indicates whether the original subexpressions had any errors. /// When true, diagnostics for missing 'template' keyword will be supressed. /// /// \param EnteringContext whether we will be entering into the context of /// the nested-name-specifier after parsing it. /// /// \param MayBePseudoDestructor When non-NULL, points to a flag that /// indicates whether this nested-name-specifier may be part of a /// pseudo-destructor name. In this case, the flag will be set false /// if we don't actually end up parsing a destructor name. Moreover, /// if we do end up determining that we are parsing a destructor name, /// the last component of the nested-name-specifier is not parsed as /// part of the scope specifier. /// /// \param IsTypename If \c true, this nested-name-specifier is known to be /// part of a type name. This is used to improve error recovery. /// /// \param LastII When non-NULL, points to an IdentifierInfo* that will be /// filled in with the leading identifier in the last component of the /// nested-name-specifier, if any. /// /// \param OnlyNamespace If true, only considers namespaces in lookup. /// /// /// \returns true if there was an error parsing a scope specifier bool Parser::ParseOptionalCXXScopeSpecifier( CXXScopeSpec &SS, ParsedType ObjectType, bool ObjectHadErrors, bool EnteringContext, bool *MayBePseudoDestructor, bool IsTypename, IdentifierInfo **LastII, bool OnlyNamespace, bool InUsingDeclaration) { assert(getLangOpts().CPlusPlus && "Call sites of this function should be guarded by checking for C++"); if (Tok.is(tok::annot_cxxscope)) { assert(!LastII && "want last identifier but have already annotated scope"); assert(!MayBePseudoDestructor && "unexpected annot_cxxscope"); Actions.RestoreNestedNameSpecifierAnnotation(Tok.getAnnotationValue(), Tok.getAnnotationRange(), SS); ConsumeAnnotationToken(); return false; } // Has to happen before any "return false"s in this function. bool CheckForDestructor = false; if (MayBePseudoDestructor && *MayBePseudoDestructor) { CheckForDestructor = true; *MayBePseudoDestructor = false; } if (LastII) *LastII = nullptr; bool HasScopeSpecifier = false; if (Tok.is(tok::coloncolon)) { // ::new and ::delete aren't nested-name-specifiers. tok::TokenKind NextKind = NextToken().getKind(); if (NextKind == tok::kw_new || NextKind == tok::kw_delete) return false; if (NextKind == tok::l_brace) { // It is invalid to have :: {, consume the scope qualifier and pretend // like we never saw it. Diag(ConsumeToken(), diag::err_expected) << tok::identifier; } else { // '::' - Global scope qualifier. if (Actions.ActOnCXXGlobalScopeSpecifier(ConsumeToken(), SS)) return true; HasScopeSpecifier = true; } } if (Tok.is(tok::kw___super)) { SourceLocation SuperLoc = ConsumeToken(); if (!Tok.is(tok::coloncolon)) { Diag(Tok.getLocation(), diag::err_expected_coloncolon_after_super); return true; } return Actions.ActOnSuperScopeSpecifier(SuperLoc, ConsumeToken(), SS); } if (!HasScopeSpecifier && Tok.isOneOf(tok::kw_decltype, tok::annot_decltype)) { DeclSpec DS(AttrFactory); SourceLocation DeclLoc = Tok.getLocation(); SourceLocation EndLoc = ParseDecltypeSpecifier(DS); SourceLocation CCLoc; // Work around a standard defect: 'decltype(auto)::' is not a // nested-name-specifier. if (DS.getTypeSpecType() == DeclSpec::TST_decltype_auto || !TryConsumeToken(tok::coloncolon, CCLoc)) { AnnotateExistingDecltypeSpecifier(DS, DeclLoc, EndLoc); return false; } if (Actions.ActOnCXXNestedNameSpecifierDecltype(SS, DS, CCLoc)) SS.SetInvalid(SourceRange(DeclLoc, CCLoc)); HasScopeSpecifier = true; } // Preferred type might change when parsing qualifiers, we need the original. auto SavedType = PreferredType; while (true) { if (HasScopeSpecifier) { if (Tok.is(tok::code_completion)) { cutOffParsing(); // Code completion for a nested-name-specifier, where the code // completion token follows the '::'. Actions.CodeCompleteQualifiedId(getCurScope(), SS, EnteringContext, InUsingDeclaration, ObjectType.get(), SavedType.get(SS.getBeginLoc())); // Include code completion token into the range of the scope otherwise // when we try to annotate the scope tokens the dangling code completion // token will cause assertion in // Preprocessor::AnnotatePreviousCachedTokens. SS.setEndLoc(Tok.getLocation()); return true; } // C++ [basic.lookup.classref]p5: // If the qualified-id has the form // // ::class-name-or-namespace-name::... // // the class-name-or-namespace-name is looked up in global scope as a // class-name or namespace-name. // // To implement this, we clear out the object type as soon as we've // seen a leading '::' or part of a nested-name-specifier. ObjectType = nullptr; } // nested-name-specifier: // nested-name-specifier 'template'[opt] simple-template-id '::' // Parse the optional 'template' keyword, then make sure we have // 'identifier <' after it. if (Tok.is(tok::kw_template)) { // If we don't have a scope specifier or an object type, this isn't a // nested-name-specifier, since they aren't allowed to start with // 'template'. if (!HasScopeSpecifier && !ObjectType) break; TentativeParsingAction TPA(*this); SourceLocation TemplateKWLoc = ConsumeToken(); UnqualifiedId TemplateName; if (Tok.is(tok::identifier)) { // Consume the identifier. TemplateName.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation()); ConsumeToken(); } else if (Tok.is(tok::kw_operator)) { // We don't need to actually parse the unqualified-id in this case, // because a simple-template-id cannot start with 'operator', but // go ahead and parse it anyway for consistency with the case where // we already annotated the template-id. if (ParseUnqualifiedIdOperator(SS, EnteringContext, ObjectType, TemplateName)) { TPA.Commit(); break; } if (TemplateName.getKind() != UnqualifiedIdKind::IK_OperatorFunctionId && TemplateName.getKind() != UnqualifiedIdKind::IK_LiteralOperatorId) { Diag(TemplateName.getSourceRange().getBegin(), diag::err_id_after_template_in_nested_name_spec) << TemplateName.getSourceRange(); TPA.Commit(); break; } } else { TPA.Revert(); break; } // If the next token is not '<', we have a qualified-id that refers // to a template name, such as T::template apply, but is not a // template-id. if (Tok.isNot(tok::less)) { TPA.Revert(); break; } // Commit to parsing the template-id. TPA.Commit(); TemplateTy Template; TemplateNameKind TNK = Actions.ActOnTemplateName( getCurScope(), SS, TemplateKWLoc, TemplateName, ObjectType, EnteringContext, Template, /*AllowInjectedClassName*/ true); if (AnnotateTemplateIdToken(Template, TNK, SS, TemplateKWLoc, TemplateName, false)) return true; continue; } if (Tok.is(tok::annot_template_id) && NextToken().is(tok::coloncolon)) { // We have // // template-id '::' // // So we need to check whether the template-id is a simple-template-id of // the right kind (it should name a type or be dependent), and then // convert it into a type within the nested-name-specifier. TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok); if (CheckForDestructor && GetLookAheadToken(2).is(tok::tilde)) { *MayBePseudoDestructor = true; return false; } if (LastII) *LastII = TemplateId->Name; // Consume the template-id token. ConsumeAnnotationToken(); assert(Tok.is(tok::coloncolon) && "NextToken() not working properly!"); SourceLocation CCLoc = ConsumeToken(); HasScopeSpecifier = true; ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), TemplateId->NumArgs); if (TemplateId->isInvalid() || Actions.ActOnCXXNestedNameSpecifier(getCurScope(), SS, TemplateId->TemplateKWLoc, TemplateId->Template, TemplateId->TemplateNameLoc, TemplateId->LAngleLoc, TemplateArgsPtr, TemplateId->RAngleLoc, CCLoc, EnteringContext)) { SourceLocation StartLoc = SS.getBeginLoc().isValid()? SS.getBeginLoc() : TemplateId->TemplateNameLoc; SS.SetInvalid(SourceRange(StartLoc, CCLoc)); } continue; } // The rest of the nested-name-specifier possibilities start with // tok::identifier. if (Tok.isNot(tok::identifier)) break; IdentifierInfo &II = *Tok.getIdentifierInfo(); // nested-name-specifier: // type-name '::' // namespace-name '::' // nested-name-specifier identifier '::' Token Next = NextToken(); Sema::NestedNameSpecInfo IdInfo(&II, Tok.getLocation(), Next.getLocation(), ObjectType); // If we get foo:bar, this is almost certainly a typo for foo::bar. Recover // and emit a fixit hint for it. if (Next.is(tok::colon) && !ColonIsSacred) { if (Actions.IsInvalidUnlessNestedName(getCurScope(), SS, IdInfo, EnteringContext) && // If the token after the colon isn't an identifier, it's still an // error, but they probably meant something else strange so don't // recover like this. PP.LookAhead(1).is(tok::identifier)) { Diag(Next, diag::err_unexpected_colon_in_nested_name_spec) << FixItHint::CreateReplacement(Next.getLocation(), "::"); // Recover as if the user wrote '::'. Next.setKind(tok::coloncolon); } } if (Next.is(tok::coloncolon) && GetLookAheadToken(2).is(tok::l_brace)) { // It is invalid to have :: {, consume the scope qualifier and pretend // like we never saw it. Token Identifier = Tok; // Stash away the identifier. ConsumeToken(); // Eat the identifier, current token is now '::'. Diag(PP.getLocForEndOfToken(ConsumeToken()), diag::err_expected) << tok::identifier; UnconsumeToken(Identifier); // Stick the identifier back. Next = NextToken(); // Point Next at the '{' token. } if (Next.is(tok::coloncolon)) { if (CheckForDestructor && GetLookAheadToken(2).is(tok::tilde)) { *MayBePseudoDestructor = true; return false; } if (ColonIsSacred) { const Token &Next2 = GetLookAheadToken(2); if (Next2.is(tok::kw_private) || Next2.is(tok::kw_protected) || Next2.is(tok::kw_public) || Next2.is(tok::kw_virtual)) { Diag(Next2, diag::err_unexpected_token_in_nested_name_spec) << Next2.getName() << FixItHint::CreateReplacement(Next.getLocation(), ":"); Token ColonColon; PP.Lex(ColonColon); ColonColon.setKind(tok::colon); PP.EnterToken(ColonColon, /*IsReinject*/ true); break; } } if (LastII) *LastII = &II; // We have an identifier followed by a '::'. Lookup this name // as the name in a nested-name-specifier. Token Identifier = Tok; SourceLocation IdLoc = ConsumeToken(); assert(Tok.isOneOf(tok::coloncolon, tok::colon) && "NextToken() not working properly!"); Token ColonColon = Tok; SourceLocation CCLoc = ConsumeToken(); bool IsCorrectedToColon = false; bool *CorrectionFlagPtr = ColonIsSacred ? &IsCorrectedToColon : nullptr; if (Actions.ActOnCXXNestedNameSpecifier( getCurScope(), IdInfo, EnteringContext, SS, false, CorrectionFlagPtr, OnlyNamespace)) { // Identifier is not recognized as a nested name, but we can have // mistyped '::' instead of ':'. if (CorrectionFlagPtr && IsCorrectedToColon) { ColonColon.setKind(tok::colon); PP.EnterToken(Tok, /*IsReinject*/ true); PP.EnterToken(ColonColon, /*IsReinject*/ true); Tok = Identifier; break; } SS.SetInvalid(SourceRange(IdLoc, CCLoc)); } HasScopeSpecifier = true; continue; } CheckForTemplateAndDigraph(Next, ObjectType, EnteringContext, II, SS); // nested-name-specifier: // type-name '<' if (Next.is(tok::less)) { TemplateTy Template; UnqualifiedId TemplateName; TemplateName.setIdentifier(&II, Tok.getLocation()); bool MemberOfUnknownSpecialization; if (TemplateNameKind TNK = Actions.isTemplateName(getCurScope(), SS, /*hasTemplateKeyword=*/false, TemplateName, ObjectType, EnteringContext, Template, MemberOfUnknownSpecialization)) { // If lookup didn't find anything, we treat the name as a template-name // anyway. C++20 requires this, and in prior language modes it improves // error recovery. But before we commit to this, check that we actually // have something that looks like a template-argument-list next. if (!IsTypename && TNK == TNK_Undeclared_template && isTemplateArgumentList(1) == TPResult::False) break; // We have found a template name, so annotate this token // with a template-id annotation. We do not permit the // template-id to be translated into a type annotation, // because some clients (e.g., the parsing of class template // specializations) still want to see the original template-id // token, and it might not be a type at all (e.g. a concept name in a // type-constraint). ConsumeToken(); if (AnnotateTemplateIdToken(Template, TNK, SS, SourceLocation(), TemplateName, false)) return true; continue; } if (MemberOfUnknownSpecialization && (ObjectType || SS.isSet()) && (IsTypename || isTemplateArgumentList(1) == TPResult::True)) { // If we had errors before, ObjectType can be dependent even without any // templates. Do not report missing template keyword in that case. if (!ObjectHadErrors) { // We have something like t::getAs, where getAs is a // member of an unknown specialization. However, this will only // parse correctly as a template, so suggest the keyword 'template' // before 'getAs' and treat this as a dependent template name. unsigned DiagID = diag::err_missing_dependent_template_keyword; if (getLangOpts().MicrosoftExt) DiagID = diag::warn_missing_dependent_template_keyword; Diag(Tok.getLocation(), DiagID) << II.getName() << FixItHint::CreateInsertion(Tok.getLocation(), "template "); } SourceLocation TemplateNameLoc = ConsumeToken(); TemplateNameKind TNK = Actions.ActOnTemplateName( getCurScope(), SS, TemplateNameLoc, TemplateName, ObjectType, EnteringContext, Template, /*AllowInjectedClassName*/ true); if (AnnotateTemplateIdToken(Template, TNK, SS, SourceLocation(), TemplateName, false)) return true; continue; } } // We don't have any tokens that form the beginning of a // nested-name-specifier, so we're done. break; } // Even if we didn't see any pieces of a nested-name-specifier, we // still check whether there is a tilde in this position, which // indicates a potential pseudo-destructor. if (CheckForDestructor && !HasScopeSpecifier && Tok.is(tok::tilde)) *MayBePseudoDestructor = true; return false; } ExprResult Parser::tryParseCXXIdExpression(CXXScopeSpec &SS, bool isAddressOfOperand, Token &Replacement) { ExprResult E; // We may have already annotated this id-expression. switch (Tok.getKind()) { case tok::annot_non_type: { NamedDecl *ND = getNonTypeAnnotation(Tok); SourceLocation Loc = ConsumeAnnotationToken(); E = Actions.ActOnNameClassifiedAsNonType(getCurScope(), SS, ND, Loc, Tok); break; } case tok::annot_non_type_dependent: { IdentifierInfo *II = getIdentifierAnnotation(Tok); SourceLocation Loc = ConsumeAnnotationToken(); // This is only the direct operand of an & operator if it is not // followed by a postfix-expression suffix. if (isAddressOfOperand && isPostfixExpressionSuffixStart()) isAddressOfOperand = false; E = Actions.ActOnNameClassifiedAsDependentNonType(SS, II, Loc, isAddressOfOperand); break; } case tok::annot_non_type_undeclared: { assert(SS.isEmpty() && "undeclared non-type annotation should be unqualified"); IdentifierInfo *II = getIdentifierAnnotation(Tok); SourceLocation Loc = ConsumeAnnotationToken(); E = Actions.ActOnNameClassifiedAsUndeclaredNonType(II, Loc); break; } default: SourceLocation TemplateKWLoc; UnqualifiedId Name; if (ParseUnqualifiedId(SS, /*ObjectType=*/nullptr, /*ObjectHadErrors=*/false, /*EnteringContext=*/false, /*AllowDestructorName=*/false, /*AllowConstructorName=*/false, /*AllowDeductionGuide=*/false, &TemplateKWLoc, Name)) return ExprError(); // This is only the direct operand of an & operator if it is not // followed by a postfix-expression suffix. if (isAddressOfOperand && isPostfixExpressionSuffixStart()) isAddressOfOperand = false; E = Actions.ActOnIdExpression( getCurScope(), SS, TemplateKWLoc, Name, Tok.is(tok::l_paren), isAddressOfOperand, /*CCC=*/nullptr, /*IsInlineAsmIdentifier=*/false, &Replacement); break; } if (!E.isInvalid() && !E.isUnset() && Tok.is(tok::less)) checkPotentialAngleBracket(E); return E; } /// ParseCXXIdExpression - Handle id-expression. /// /// id-expression: /// unqualified-id /// qualified-id /// /// qualified-id: /// '::'[opt] nested-name-specifier 'template'[opt] unqualified-id /// '::' identifier /// '::' operator-function-id /// '::' template-id /// /// NOTE: The standard specifies that, for qualified-id, the parser does not /// expect: /// /// '::' conversion-function-id /// '::' '~' class-name /// /// This may cause a slight inconsistency on diagnostics: /// /// class C {}; /// namespace A {} /// void f() { /// :: A :: ~ C(); // Some Sema error about using destructor with a /// // namespace. /// :: ~ C(); // Some Parser error like 'unexpected ~'. /// } /// /// We simplify the parser a bit and make it work like: /// /// qualified-id: /// '::'[opt] nested-name-specifier 'template'[opt] unqualified-id /// '::' unqualified-id /// /// That way Sema can handle and report similar errors for namespaces and the /// global scope. /// /// The isAddressOfOperand parameter indicates that this id-expression is a /// direct operand of the address-of operator. This is, besides member contexts, /// the only place where a qualified-id naming a non-static class member may /// appear. /// ExprResult Parser::ParseCXXIdExpression(bool isAddressOfOperand) { // qualified-id: // '::'[opt] nested-name-specifier 'template'[opt] unqualified-id // '::' unqualified-id // CXXScopeSpec SS; ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr, /*ObjectHadErrors=*/false, /*EnteringContext=*/false); Token Replacement; ExprResult Result = tryParseCXXIdExpression(SS, isAddressOfOperand, Replacement); if (Result.isUnset()) { // If the ExprResult is valid but null, then typo correction suggested a // keyword replacement that needs to be reparsed. UnconsumeToken(Replacement); Result = tryParseCXXIdExpression(SS, isAddressOfOperand, Replacement); } assert(!Result.isUnset() && "Typo correction suggested a keyword replacement " "for a previous keyword suggestion"); return Result; } /// ParseLambdaExpression - Parse a C++11 lambda expression. /// /// lambda-expression: /// lambda-introducer lambda-declarator compound-statement /// lambda-introducer '<' template-parameter-list '>' /// requires-clause[opt] lambda-declarator compound-statement /// /// lambda-introducer: /// '[' lambda-capture[opt] ']' /// /// lambda-capture: /// capture-default /// capture-list /// capture-default ',' capture-list /// /// capture-default: /// '&' /// '=' /// /// capture-list: /// capture /// capture-list ',' capture /// /// capture: /// simple-capture /// init-capture [C++1y] /// /// simple-capture: /// identifier /// '&' identifier /// 'this' /// /// init-capture: [C++1y] /// identifier initializer /// '&' identifier initializer /// /// lambda-declarator: /// lambda-specifiers [C++2b] /// '(' parameter-declaration-clause ')' lambda-specifiers /// requires-clause[opt] /// /// lambda-specifiers: /// decl-specifier-seq[opt] noexcept-specifier[opt] /// attribute-specifier-seq[opt] trailing-return-type[opt] /// ExprResult Parser::ParseLambdaExpression() { // Parse lambda-introducer. LambdaIntroducer Intro; if (ParseLambdaIntroducer(Intro)) { SkipUntil(tok::r_square, StopAtSemi); SkipUntil(tok::l_brace, StopAtSemi); SkipUntil(tok::r_brace, StopAtSemi); return ExprError(); } return ParseLambdaExpressionAfterIntroducer(Intro); } /// Use lookahead and potentially tentative parsing to determine if we are /// looking at a C++11 lambda expression, and parse it if we are. /// /// If we are not looking at a lambda expression, returns ExprError(). ExprResult Parser::TryParseLambdaExpression() { assert(getLangOpts().CPlusPlus11 && Tok.is(tok::l_square) && "Not at the start of a possible lambda expression."); const Token Next = NextToken(); if (Next.is(tok::eof)) // Nothing else to lookup here... return ExprEmpty(); const Token After = GetLookAheadToken(2); // If lookahead indicates this is a lambda... if (Next.is(tok::r_square) || // [] Next.is(tok::equal) || // [= (Next.is(tok::amp) && // [&] or [&, After.isOneOf(tok::r_square, tok::comma)) || (Next.is(tok::identifier) && // [identifier] After.is(tok::r_square)) || Next.is(tok::ellipsis)) { // [... return ParseLambdaExpression(); } // If lookahead indicates an ObjC message send... // [identifier identifier if (Next.is(tok::identifier) && After.is(tok::identifier)) return ExprEmpty(); // Here, we're stuck: lambda introducers and Objective-C message sends are // unambiguous, but it requires arbitrary lookhead. [a,b,c,d,e,f,g] is a // lambda, and [a,b,c,d,e,f,g h] is a Objective-C message send. Instead of // writing two routines to parse a lambda introducer, just try to parse // a lambda introducer first, and fall back if that fails. LambdaIntroducer Intro; { TentativeParsingAction TPA(*this); LambdaIntroducerTentativeParse Tentative; if (ParseLambdaIntroducer(Intro, &Tentative)) { TPA.Commit(); return ExprError(); } switch (Tentative) { case LambdaIntroducerTentativeParse::Success: TPA.Commit(); break; case LambdaIntroducerTentativeParse::Incomplete: // Didn't fully parse the lambda-introducer, try again with a // non-tentative parse. TPA.Revert(); Intro = LambdaIntroducer(); if (ParseLambdaIntroducer(Intro)) return ExprError(); break; case LambdaIntroducerTentativeParse::MessageSend: case LambdaIntroducerTentativeParse::Invalid: // Not a lambda-introducer, might be a message send. TPA.Revert(); return ExprEmpty(); } } return ParseLambdaExpressionAfterIntroducer(Intro); } /// Parse a lambda introducer. /// \param Intro A LambdaIntroducer filled in with information about the /// contents of the lambda-introducer. /// \param Tentative If non-null, we are disambiguating between a /// lambda-introducer and some other construct. In this mode, we do not /// produce any diagnostics or take any other irreversible action unless /// we're sure that this is a lambda-expression. /// \return \c true if parsing (or disambiguation) failed with a diagnostic and /// the caller should bail out / recover. bool Parser::ParseLambdaIntroducer(LambdaIntroducer &Intro, LambdaIntroducerTentativeParse *Tentative) { if (Tentative) *Tentative = LambdaIntroducerTentativeParse::Success; assert(Tok.is(tok::l_square) && "Lambda expressions begin with '['."); BalancedDelimiterTracker T(*this, tok::l_square); T.consumeOpen(); Intro.Range.setBegin(T.getOpenLocation()); bool First = true; // Produce a diagnostic if we're not tentatively parsing; otherwise track // that our parse has failed. auto Invalid = [&](llvm::function_ref Action) { if (Tentative) { *Tentative = LambdaIntroducerTentativeParse::Invalid; return false; } Action(); return true; }; // Perform some irreversible action if this is a non-tentative parse; // otherwise note that our actions were incomplete. auto NonTentativeAction = [&](llvm::function_ref Action) { if (Tentative) *Tentative = LambdaIntroducerTentativeParse::Incomplete; else Action(); }; // Parse capture-default. if (Tok.is(tok::amp) && (NextToken().is(tok::comma) || NextToken().is(tok::r_square))) { Intro.Default = LCD_ByRef; Intro.DefaultLoc = ConsumeToken(); First = false; if (!Tok.getIdentifierInfo()) { // This can only be a lambda; no need for tentative parsing any more. // '[[and]]' can still be an attribute, though. Tentative = nullptr; } } else if (Tok.is(tok::equal)) { Intro.Default = LCD_ByCopy; Intro.DefaultLoc = ConsumeToken(); First = false; Tentative = nullptr; } while (Tok.isNot(tok::r_square)) { if (!First) { if (Tok.isNot(tok::comma)) { // Provide a completion for a lambda introducer here. Except // in Objective-C, where this is Almost Surely meant to be a message // send. In that case, fail here and let the ObjC message // expression parser perform the completion. if (Tok.is(tok::code_completion) && !(getLangOpts().ObjC && Tentative)) { cutOffParsing(); Actions.CodeCompleteLambdaIntroducer(getCurScope(), Intro, /*AfterAmpersand=*/false); break; } return Invalid([&] { Diag(Tok.getLocation(), diag::err_expected_comma_or_rsquare); }); } ConsumeToken(); } if (Tok.is(tok::code_completion)) { cutOffParsing(); // If we're in Objective-C++ and we have a bare '[', then this is more // likely to be a message receiver. if (getLangOpts().ObjC && Tentative && First) Actions.CodeCompleteObjCMessageReceiver(getCurScope()); else Actions.CodeCompleteLambdaIntroducer(getCurScope(), Intro, /*AfterAmpersand=*/false); break; } First = false; // Parse capture. LambdaCaptureKind Kind = LCK_ByCopy; LambdaCaptureInitKind InitKind = LambdaCaptureInitKind::NoInit; SourceLocation Loc; IdentifierInfo *Id = nullptr; SourceLocation EllipsisLocs[4]; ExprResult Init; SourceLocation LocStart = Tok.getLocation(); if (Tok.is(tok::star)) { Loc = ConsumeToken(); if (Tok.is(tok::kw_this)) { ConsumeToken(); Kind = LCK_StarThis; } else { return Invalid([&] { Diag(Tok.getLocation(), diag::err_expected_star_this_capture); }); } } else if (Tok.is(tok::kw_this)) { Kind = LCK_This; Loc = ConsumeToken(); } else if (Tok.isOneOf(tok::amp, tok::equal) && NextToken().isOneOf(tok::comma, tok::r_square) && Intro.Default == LCD_None) { // We have a lone "&" or "=" which is either a misplaced capture-default // or the start of a capture (in the "&" case) with the rest of the // capture missing. Both are an error but a misplaced capture-default // is more likely if we don't already have a capture default. return Invalid( [&] { Diag(Tok.getLocation(), diag::err_capture_default_first); }); } else { TryConsumeToken(tok::ellipsis, EllipsisLocs[0]); if (Tok.is(tok::amp)) { Kind = LCK_ByRef; ConsumeToken(); if (Tok.is(tok::code_completion)) { cutOffParsing(); Actions.CodeCompleteLambdaIntroducer(getCurScope(), Intro, /*AfterAmpersand=*/true); break; } } TryConsumeToken(tok::ellipsis, EllipsisLocs[1]); if (Tok.is(tok::identifier)) { Id = Tok.getIdentifierInfo(); Loc = ConsumeToken(); } else if (Tok.is(tok::kw_this)) { return Invalid([&] { // FIXME: Suggest a fixit here. Diag(Tok.getLocation(), diag::err_this_captured_by_reference); }); } else { return Invalid([&] { Diag(Tok.getLocation(), diag::err_expected_capture); }); } TryConsumeToken(tok::ellipsis, EllipsisLocs[2]); if (Tok.is(tok::l_paren)) { BalancedDelimiterTracker Parens(*this, tok::l_paren); Parens.consumeOpen(); InitKind = LambdaCaptureInitKind::DirectInit; ExprVector Exprs; CommaLocsTy Commas; if (Tentative) { Parens.skipToEnd(); *Tentative = LambdaIntroducerTentativeParse::Incomplete; } else if (ParseExpressionList(Exprs, Commas)) { Parens.skipToEnd(); Init = ExprError(); } else { Parens.consumeClose(); Init = Actions.ActOnParenListExpr(Parens.getOpenLocation(), Parens.getCloseLocation(), Exprs); } } else if (Tok.isOneOf(tok::l_brace, tok::equal)) { // Each lambda init-capture forms its own full expression, which clears // Actions.MaybeODRUseExprs. So create an expression evaluation context // to save the necessary state, and restore it later. EnterExpressionEvaluationContext EC( Actions, Sema::ExpressionEvaluationContext::PotentiallyEvaluated); if (TryConsumeToken(tok::equal)) InitKind = LambdaCaptureInitKind::CopyInit; else InitKind = LambdaCaptureInitKind::ListInit; if (!Tentative) { Init = ParseInitializer(); } else if (Tok.is(tok::l_brace)) { BalancedDelimiterTracker Braces(*this, tok::l_brace); Braces.consumeOpen(); Braces.skipToEnd(); *Tentative = LambdaIntroducerTentativeParse::Incomplete; } else { // We're disambiguating this: // // [..., x = expr // // We need to find the end of the following expression in order to // determine whether this is an Obj-C message send's receiver, a // C99 designator, or a lambda init-capture. // // Parse the expression to find where it ends, and annotate it back // onto the tokens. We would have parsed this expression the same way // in either case: both the RHS of an init-capture and the RHS of an // assignment expression are parsed as an initializer-clause, and in // neither case can anything be added to the scope between the '[' and // here. // // FIXME: This is horrible. Adding a mechanism to skip an expression // would be much cleaner. // FIXME: If there is a ',' before the next ']' or ':', we can skip to // that instead. (And if we see a ':' with no matching '?', we can // classify this as an Obj-C message send.) SourceLocation StartLoc = Tok.getLocation(); InMessageExpressionRAIIObject MaybeInMessageExpression(*this, true); Init = ParseInitializer(); if (!Init.isInvalid()) Init = Actions.CorrectDelayedTyposInExpr(Init.get()); if (Tok.getLocation() != StartLoc) { // Back out the lexing of the token after the initializer. PP.RevertCachedTokens(1); // Replace the consumed tokens with an appropriate annotation. Tok.setLocation(StartLoc); Tok.setKind(tok::annot_primary_expr); setExprAnnotation(Tok, Init); Tok.setAnnotationEndLoc(PP.getLastCachedTokenLocation()); PP.AnnotateCachedTokens(Tok); // Consume the annotated initializer. ConsumeAnnotationToken(); } } } TryConsumeToken(tok::ellipsis, EllipsisLocs[3]); } // Check if this is a message send before we act on a possible init-capture. if (Tentative && Tok.is(tok::identifier) && NextToken().isOneOf(tok::colon, tok::r_square)) { // This can only be a message send. We're done with disambiguation. *Tentative = LambdaIntroducerTentativeParse::MessageSend; return false; } // Ensure that any ellipsis was in the right place. SourceLocation EllipsisLoc; if (std::any_of(std::begin(EllipsisLocs), std::end(EllipsisLocs), [](SourceLocation Loc) { return Loc.isValid(); })) { // The '...' should appear before the identifier in an init-capture, and // after the identifier otherwise. bool InitCapture = InitKind != LambdaCaptureInitKind::NoInit; SourceLocation *ExpectedEllipsisLoc = !InitCapture ? &EllipsisLocs[2] : Kind == LCK_ByRef ? &EllipsisLocs[1] : &EllipsisLocs[0]; EllipsisLoc = *ExpectedEllipsisLoc; unsigned DiagID = 0; if (EllipsisLoc.isInvalid()) { DiagID = diag::err_lambda_capture_misplaced_ellipsis; for (SourceLocation Loc : EllipsisLocs) { if (Loc.isValid()) EllipsisLoc = Loc; } } else { unsigned NumEllipses = std::accumulate( std::begin(EllipsisLocs), std::end(EllipsisLocs), 0, [](int N, SourceLocation Loc) { return N + Loc.isValid(); }); if (NumEllipses > 1) DiagID = diag::err_lambda_capture_multiple_ellipses; } if (DiagID) { NonTentativeAction([&] { // Point the diagnostic at the first misplaced ellipsis. SourceLocation DiagLoc; for (SourceLocation &Loc : EllipsisLocs) { if (&Loc != ExpectedEllipsisLoc && Loc.isValid()) { DiagLoc = Loc; break; } } assert(DiagLoc.isValid() && "no location for diagnostic"); // Issue the diagnostic and produce fixits showing where the ellipsis // should have been written. auto &&D = Diag(DiagLoc, DiagID); if (DiagID == diag::err_lambda_capture_misplaced_ellipsis) { SourceLocation ExpectedLoc = InitCapture ? Loc : Lexer::getLocForEndOfToken( Loc, 0, PP.getSourceManager(), getLangOpts()); D << InitCapture << FixItHint::CreateInsertion(ExpectedLoc, "..."); } for (SourceLocation &Loc : EllipsisLocs) { if (&Loc != ExpectedEllipsisLoc && Loc.isValid()) D << FixItHint::CreateRemoval(Loc); } }); } } // Process the init-capture initializers now rather than delaying until we // form the lambda-expression so that they can be handled in the context // enclosing the lambda-expression, rather than in the context of the // lambda-expression itself. ParsedType InitCaptureType; if (Init.isUsable()) Init = Actions.CorrectDelayedTyposInExpr(Init.get()); if (Init.isUsable()) { NonTentativeAction([&] { // Get the pointer and store it in an lvalue, so we can use it as an // out argument. Expr *InitExpr = Init.get(); // This performs any lvalue-to-rvalue conversions if necessary, which // can affect what gets captured in the containing decl-context. InitCaptureType = Actions.actOnLambdaInitCaptureInitialization( Loc, Kind == LCK_ByRef, EllipsisLoc, Id, InitKind, InitExpr); Init = InitExpr; }); } SourceLocation LocEnd = PrevTokLocation; Intro.addCapture(Kind, Loc, Id, EllipsisLoc, InitKind, Init, InitCaptureType, SourceRange(LocStart, LocEnd)); } T.consumeClose(); Intro.Range.setEnd(T.getCloseLocation()); return false; } static void tryConsumeLambdaSpecifierToken(Parser &P, SourceLocation &MutableLoc, SourceLocation &ConstexprLoc, SourceLocation &ConstevalLoc, SourceLocation &DeclEndLoc) { assert(MutableLoc.isInvalid()); assert(ConstexprLoc.isInvalid()); // Consume constexpr-opt mutable-opt in any sequence, and set the DeclEndLoc // to the final of those locations. Emit an error if we have multiple // copies of those keywords and recover. while (true) { switch (P.getCurToken().getKind()) { case tok::kw_mutable: { if (MutableLoc.isValid()) { P.Diag(P.getCurToken().getLocation(), diag::err_lambda_decl_specifier_repeated) << 0 << FixItHint::CreateRemoval(P.getCurToken().getLocation()); } MutableLoc = P.ConsumeToken(); DeclEndLoc = MutableLoc; break /*switch*/; } case tok::kw_constexpr: if (ConstexprLoc.isValid()) { P.Diag(P.getCurToken().getLocation(), diag::err_lambda_decl_specifier_repeated) << 1 << FixItHint::CreateRemoval(P.getCurToken().getLocation()); } ConstexprLoc = P.ConsumeToken(); DeclEndLoc = ConstexprLoc; break /*switch*/; case tok::kw_consteval: if (ConstevalLoc.isValid()) { P.Diag(P.getCurToken().getLocation(), diag::err_lambda_decl_specifier_repeated) << 2 << FixItHint::CreateRemoval(P.getCurToken().getLocation()); } ConstevalLoc = P.ConsumeToken(); DeclEndLoc = ConstevalLoc; break /*switch*/; default: return; } } } static void addConstexprToLambdaDeclSpecifier(Parser &P, SourceLocation ConstexprLoc, DeclSpec &DS) { if (ConstexprLoc.isValid()) { P.Diag(ConstexprLoc, !P.getLangOpts().CPlusPlus17 ? diag::ext_constexpr_on_lambda_cxx17 : diag::warn_cxx14_compat_constexpr_on_lambda); const char *PrevSpec = nullptr; unsigned DiagID = 0; DS.SetConstexprSpec(ConstexprSpecKind::Constexpr, ConstexprLoc, PrevSpec, DiagID); assert(PrevSpec == nullptr && DiagID == 0 && "Constexpr cannot have been set previously!"); } } static void addConstevalToLambdaDeclSpecifier(Parser &P, SourceLocation ConstevalLoc, DeclSpec &DS) { if (ConstevalLoc.isValid()) { P.Diag(ConstevalLoc, diag::warn_cxx20_compat_consteval); const char *PrevSpec = nullptr; unsigned DiagID = 0; DS.SetConstexprSpec(ConstexprSpecKind::Consteval, ConstevalLoc, PrevSpec, DiagID); if (DiagID != 0) P.Diag(ConstevalLoc, DiagID) << PrevSpec; } } /// ParseLambdaExpressionAfterIntroducer - Parse the rest of a lambda /// expression. ExprResult Parser::ParseLambdaExpressionAfterIntroducer( LambdaIntroducer &Intro) { SourceLocation LambdaBeginLoc = Intro.Range.getBegin(); Diag(LambdaBeginLoc, diag::warn_cxx98_compat_lambda); PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), LambdaBeginLoc, "lambda expression parsing"); // FIXME: Call into Actions to add any init-capture declarations to the // scope while parsing the lambda-declarator and compound-statement. // Parse lambda-declarator[opt]. DeclSpec DS(AttrFactory); Declarator D(DS, DeclaratorContext::LambdaExpr); TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth); Actions.PushLambdaScope(); ParsedAttributes Attr(AttrFactory); if (getLangOpts().CUDA) { // In CUDA code, GNU attributes are allowed to appear immediately after the // "[...]", even if there is no "(...)" before the lambda body. MaybeParseGNUAttributes(D); } // Helper to emit a warning if we see a CUDA host/device/global attribute // after '(...)'. nvcc doesn't accept this. auto WarnIfHasCUDATargetAttr = [&] { if (getLangOpts().CUDA) for (const ParsedAttr &A : Attr) if (A.getKind() == ParsedAttr::AT_CUDADevice || A.getKind() == ParsedAttr::AT_CUDAHost || A.getKind() == ParsedAttr::AT_CUDAGlobal) Diag(A.getLoc(), diag::warn_cuda_attr_lambda_position) << A.getAttrName()->getName(); }; MultiParseScope TemplateParamScope(*this); if (Tok.is(tok::less)) { Diag(Tok, getLangOpts().CPlusPlus20 ? diag::warn_cxx17_compat_lambda_template_parameter_list : diag::ext_lambda_template_parameter_list); SmallVector TemplateParams; SourceLocation LAngleLoc, RAngleLoc; if (ParseTemplateParameters(TemplateParamScope, CurTemplateDepthTracker.getDepth(), TemplateParams, LAngleLoc, RAngleLoc)) { Actions.ActOnLambdaError(LambdaBeginLoc, getCurScope()); return ExprError(); } if (TemplateParams.empty()) { Diag(RAngleLoc, diag::err_lambda_template_parameter_list_empty); } else { ExprResult RequiresClause; if (TryConsumeToken(tok::kw_requires)) { RequiresClause = Actions.ActOnRequiresClause(ParseConstraintLogicalOrExpression( /*IsTrailingRequiresClause=*/false)); if (RequiresClause.isInvalid()) SkipUntil({tok::l_brace, tok::l_paren}, StopAtSemi | StopBeforeMatch); } Actions.ActOnLambdaExplicitTemplateParameterList( LAngleLoc, TemplateParams, RAngleLoc, RequiresClause); ++CurTemplateDepthTracker; } } // Implement WG21 P2173, which allows attributes immediately before the // lambda declarator and applies them to the corresponding function operator // or operator template declaration. We accept this as a conforming extension // in all language modes that support lambdas. if (isCXX11AttributeSpecifier()) { Diag(Tok, getLangOpts().CPlusPlus2b ? diag::warn_cxx20_compat_decl_attrs_on_lambda : diag::ext_decl_attrs_on_lambda); MaybeParseCXX11Attributes(D); } TypeResult TrailingReturnType; SourceLocation TrailingReturnTypeLoc; auto ParseLambdaSpecifiers = [&](SourceLocation LParenLoc, SourceLocation RParenLoc, MutableArrayRef ParamInfo, SourceLocation EllipsisLoc) { SourceLocation DeclEndLoc = RParenLoc; // GNU-style attributes must be parsed before the mutable specifier to // be compatible with GCC. MSVC-style attributes must be parsed before // the mutable specifier to be compatible with MSVC. MaybeParseAttributes(PAKM_GNU | PAKM_Declspec, Attr); // Parse mutable-opt and/or constexpr-opt or consteval-opt, and update // the DeclEndLoc. SourceLocation MutableLoc; SourceLocation ConstexprLoc; SourceLocation ConstevalLoc; tryConsumeLambdaSpecifierToken(*this, MutableLoc, ConstexprLoc, ConstevalLoc, DeclEndLoc); addConstexprToLambdaDeclSpecifier(*this, ConstexprLoc, DS); addConstevalToLambdaDeclSpecifier(*this, ConstevalLoc, DS); // Parse exception-specification[opt]. ExceptionSpecificationType ESpecType = EST_None; SourceRange ESpecRange; SmallVector DynamicExceptions; SmallVector DynamicExceptionRanges; ExprResult NoexceptExpr; CachedTokens *ExceptionSpecTokens; ESpecType = tryParseExceptionSpecification( /*Delayed=*/false, ESpecRange, DynamicExceptions, DynamicExceptionRanges, NoexceptExpr, ExceptionSpecTokens); if (ESpecType != EST_None) DeclEndLoc = ESpecRange.getEnd(); // Parse attribute-specifier[opt]. MaybeParseCXX11Attributes(Attr, &DeclEndLoc); // Parse OpenCL addr space attribute. if (Tok.isOneOf(tok::kw___private, tok::kw___global, tok::kw___local, tok::kw___constant, tok::kw___generic)) { ParseOpenCLQualifiers(DS.getAttributes()); ConsumeToken(); } SourceLocation FunLocalRangeEnd = DeclEndLoc; // Parse trailing-return-type[opt]. if (Tok.is(tok::arrow)) { FunLocalRangeEnd = Tok.getLocation(); SourceRange Range; TrailingReturnType = ParseTrailingReturnType( Range, /*MayBeFollowedByDirectInit*/ false); TrailingReturnTypeLoc = Range.getBegin(); if (Range.getEnd().isValid()) DeclEndLoc = Range.getEnd(); } SourceLocation NoLoc; D.AddTypeInfo( DeclaratorChunk::getFunction( /*HasProto=*/true, /*IsAmbiguous=*/false, LParenLoc, ParamInfo.data(), ParamInfo.size(), EllipsisLoc, RParenLoc, /*RefQualifierIsLvalueRef=*/true, /*RefQualifierLoc=*/NoLoc, MutableLoc, ESpecType, ESpecRange, DynamicExceptions.data(), DynamicExceptionRanges.data(), DynamicExceptions.size(), NoexceptExpr.isUsable() ? NoexceptExpr.get() : nullptr, /*ExceptionSpecTokens*/ nullptr, /*DeclsInPrototype=*/None, LParenLoc, FunLocalRangeEnd, D, TrailingReturnType, TrailingReturnTypeLoc, &DS), std::move(Attr), DeclEndLoc); }; if (Tok.is(tok::l_paren)) { ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope | Scope::FunctionDeclarationScope | Scope::DeclScope); BalancedDelimiterTracker T(*this, tok::l_paren); T.consumeOpen(); SourceLocation LParenLoc = T.getOpenLocation(); // Parse parameter-declaration-clause. SmallVector ParamInfo; SourceLocation EllipsisLoc; if (Tok.isNot(tok::r_paren)) { Actions.RecordParsingTemplateParameterDepth( CurTemplateDepthTracker.getOriginalDepth()); ParseParameterDeclarationClause(D.getContext(), Attr, ParamInfo, EllipsisLoc); // For a generic lambda, each 'auto' within the parameter declaration // clause creates a template type parameter, so increment the depth. // If we've parsed any explicit template parameters, then the depth will // have already been incremented. So we make sure that at most a single // depth level is added. if (Actions.getCurGenericLambda()) CurTemplateDepthTracker.setAddedDepth(1); } T.consumeClose(); // Parse lambda-specifiers. ParseLambdaSpecifiers(LParenLoc, /*DeclEndLoc=*/T.getCloseLocation(), ParamInfo, EllipsisLoc); // Parse requires-clause[opt]. if (Tok.is(tok::kw_requires)) ParseTrailingRequiresClause(D); } else if (Tok.isOneOf(tok::kw_mutable, tok::arrow, tok::kw___attribute, tok::kw_constexpr, tok::kw_consteval, tok::kw___private, tok::kw___global, tok::kw___local, tok::kw___constant, tok::kw___generic, tok::kw_requires, tok::kw_noexcept) || (Tok.is(tok::l_square) && NextToken().is(tok::l_square))) { if (!getLangOpts().CPlusPlus2b) // It's common to forget that one needs '()' before 'mutable', an // attribute specifier, the result type, or the requires clause. Deal with // this. Diag(Tok, diag::ext_lambda_missing_parens) << FixItHint::CreateInsertion(Tok.getLocation(), "() "); SourceLocation NoLoc; // Parse lambda-specifiers. std::vector EmptyParamInfo; ParseLambdaSpecifiers(/*LParenLoc=*/NoLoc, /*RParenLoc=*/NoLoc, EmptyParamInfo, /*EllipsisLoc=*/NoLoc); } WarnIfHasCUDATargetAttr(); // FIXME: Rename BlockScope -> ClosureScope if we decide to continue using // it. unsigned ScopeFlags = Scope::BlockScope | Scope::FnScope | Scope::DeclScope | Scope::CompoundStmtScope; ParseScope BodyScope(this, ScopeFlags); Actions.ActOnStartOfLambdaDefinition(Intro, D, getCurScope()); // Parse compound-statement. if (!Tok.is(tok::l_brace)) { Diag(Tok, diag::err_expected_lambda_body); Actions.ActOnLambdaError(LambdaBeginLoc, getCurScope()); return ExprError(); } StmtResult Stmt(ParseCompoundStatementBody()); BodyScope.Exit(); TemplateParamScope.Exit(); if (!Stmt.isInvalid() && !TrailingReturnType.isInvalid()) return Actions.ActOnLambdaExpr(LambdaBeginLoc, Stmt.get(), getCurScope()); Actions.ActOnLambdaError(LambdaBeginLoc, getCurScope()); return ExprError(); } /// ParseCXXCasts - This handles the various ways to cast expressions to another /// type. /// /// postfix-expression: [C++ 5.2p1] /// 'dynamic_cast' '<' type-name '>' '(' expression ')' /// 'static_cast' '<' type-name '>' '(' expression ')' /// 'reinterpret_cast' '<' type-name '>' '(' expression ')' /// 'const_cast' '<' type-name '>' '(' expression ')' /// /// C++ for OpenCL s2.3.1 adds: /// 'addrspace_cast' '<' type-name '>' '(' expression ')' ExprResult Parser::ParseCXXCasts() { tok::TokenKind Kind = Tok.getKind(); const char *CastName = nullptr; // For error messages switch (Kind) { default: llvm_unreachable("Unknown C++ cast!"); case tok::kw_addrspace_cast: CastName = "addrspace_cast"; break; case tok::kw_const_cast: CastName = "const_cast"; break; case tok::kw_dynamic_cast: CastName = "dynamic_cast"; break; case tok::kw_reinterpret_cast: CastName = "reinterpret_cast"; break; case tok::kw_static_cast: CastName = "static_cast"; break; } SourceLocation OpLoc = ConsumeToken(); SourceLocation LAngleBracketLoc = Tok.getLocation(); // Check for "<::" which is parsed as "[:". If found, fix token stream, // diagnose error, suggest fix, and recover parsing. if (Tok.is(tok::l_square) && Tok.getLength() == 2) { Token Next = NextToken(); if (Next.is(tok::colon) && areTokensAdjacent(Tok, Next)) FixDigraph(*this, PP, Tok, Next, Kind, /*AtDigraph*/true); } if (ExpectAndConsume(tok::less, diag::err_expected_less_after, CastName)) return ExprError(); // Parse the common declaration-specifiers piece. DeclSpec DS(AttrFactory); ParseSpecifierQualifierList(DS); // Parse the abstract-declarator, if present. Declarator DeclaratorInfo(DS, DeclaratorContext::TypeName); ParseDeclarator(DeclaratorInfo); SourceLocation RAngleBracketLoc = Tok.getLocation(); if (ExpectAndConsume(tok::greater)) return ExprError(Diag(LAngleBracketLoc, diag::note_matching) << tok::less); BalancedDelimiterTracker T(*this, tok::l_paren); if (T.expectAndConsume(diag::err_expected_lparen_after, CastName)) return ExprError(); ExprResult Result = ParseExpression(); // Match the ')'. T.consumeClose(); if (!Result.isInvalid() && !DeclaratorInfo.isInvalidType()) Result = Actions.ActOnCXXNamedCast(OpLoc, Kind, LAngleBracketLoc, DeclaratorInfo, RAngleBracketLoc, T.getOpenLocation(), Result.get(), T.getCloseLocation()); return Result; } /// ParseCXXTypeid - This handles the C++ typeid expression. /// /// postfix-expression: [C++ 5.2p1] /// 'typeid' '(' expression ')' /// 'typeid' '(' type-id ')' /// ExprResult Parser::ParseCXXTypeid() { assert(Tok.is(tok::kw_typeid) && "Not 'typeid'!"); SourceLocation OpLoc = ConsumeToken(); SourceLocation LParenLoc, RParenLoc; BalancedDelimiterTracker T(*this, tok::l_paren); // typeid expressions are always parenthesized. if (T.expectAndConsume(diag::err_expected_lparen_after, "typeid")) return ExprError(); LParenLoc = T.getOpenLocation(); ExprResult Result; // C++0x [expr.typeid]p3: // When typeid is applied to an expression other than an lvalue of a // polymorphic class type [...] The expression is an unevaluated // operand (Clause 5). // // Note that we can't tell whether the expression is an lvalue of a // polymorphic class type until after we've parsed the expression; we // speculatively assume the subexpression is unevaluated, and fix it up // later. // // We enter the unevaluated context before trying to determine whether we // have a type-id, because the tentative parse logic will try to resolve // names, and must treat them as unevaluated. EnterExpressionEvaluationContext Unevaluated( Actions, Sema::ExpressionEvaluationContext::Unevaluated, Sema::ReuseLambdaContextDecl); if (isTypeIdInParens()) { TypeResult Ty = ParseTypeName(); // Match the ')'. T.consumeClose(); RParenLoc = T.getCloseLocation(); if (Ty.isInvalid() || RParenLoc.isInvalid()) return ExprError(); Result = Actions.ActOnCXXTypeid(OpLoc, LParenLoc, /*isType=*/true, Ty.get().getAsOpaquePtr(), RParenLoc); } else { Result = ParseExpression(); // Match the ')'. if (Result.isInvalid()) SkipUntil(tok::r_paren, StopAtSemi); else { T.consumeClose(); RParenLoc = T.getCloseLocation(); if (RParenLoc.isInvalid()) return ExprError(); Result = Actions.ActOnCXXTypeid(OpLoc, LParenLoc, /*isType=*/false, Result.get(), RParenLoc); } } return Result; } /// ParseCXXUuidof - This handles the Microsoft C++ __uuidof expression. /// /// '__uuidof' '(' expression ')' /// '__uuidof' '(' type-id ')' /// ExprResult Parser::ParseCXXUuidof() { assert(Tok.is(tok::kw___uuidof) && "Not '__uuidof'!"); SourceLocation OpLoc = ConsumeToken(); BalancedDelimiterTracker T(*this, tok::l_paren); // __uuidof expressions are always parenthesized. if (T.expectAndConsume(diag::err_expected_lparen_after, "__uuidof")) return ExprError(); ExprResult Result; if (isTypeIdInParens()) { TypeResult Ty = ParseTypeName(); // Match the ')'. T.consumeClose(); if (Ty.isInvalid()) return ExprError(); Result = Actions.ActOnCXXUuidof(OpLoc, T.getOpenLocation(), /*isType=*/true, Ty.get().getAsOpaquePtr(), T.getCloseLocation()); } else { EnterExpressionEvaluationContext Unevaluated( Actions, Sema::ExpressionEvaluationContext::Unevaluated); Result = ParseExpression(); // Match the ')'. if (Result.isInvalid()) SkipUntil(tok::r_paren, StopAtSemi); else { T.consumeClose(); Result = Actions.ActOnCXXUuidof(OpLoc, T.getOpenLocation(), /*isType=*/false, Result.get(), T.getCloseLocation()); } } return Result; } /// Parse a C++ pseudo-destructor expression after the base, /// . or -> operator, and nested-name-specifier have already been /// parsed. We're handling this fragment of the grammar: /// /// postfix-expression: [C++2a expr.post] /// postfix-expression . template[opt] id-expression /// postfix-expression -> template[opt] id-expression /// /// id-expression: /// qualified-id /// unqualified-id /// /// qualified-id: /// nested-name-specifier template[opt] unqualified-id /// /// nested-name-specifier: /// type-name :: /// decltype-specifier :: FIXME: not implemented, but probably only /// allowed in C++ grammar by accident /// nested-name-specifier identifier :: /// nested-name-specifier template[opt] simple-template-id :: /// [...] /// /// unqualified-id: /// ~ type-name /// ~ decltype-specifier /// [...] /// /// ... where the all but the last component of the nested-name-specifier /// has already been parsed, and the base expression is not of a non-dependent /// class type. ExprResult Parser::ParseCXXPseudoDestructor(Expr *Base, SourceLocation OpLoc, tok::TokenKind OpKind, CXXScopeSpec &SS, ParsedType ObjectType) { // If the last component of the (optional) nested-name-specifier is // template[opt] simple-template-id, it has already been annotated. UnqualifiedId FirstTypeName; SourceLocation CCLoc; if (Tok.is(tok::identifier)) { FirstTypeName.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation()); ConsumeToken(); assert(Tok.is(tok::coloncolon) &&"ParseOptionalCXXScopeSpecifier fail"); CCLoc = ConsumeToken(); } else if (Tok.is(tok::annot_template_id)) { TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok); // FIXME: Carry on and build an AST representation for tooling. if (TemplateId->isInvalid()) return ExprError(); FirstTypeName.setTemplateId(TemplateId); ConsumeAnnotationToken(); assert(Tok.is(tok::coloncolon) &&"ParseOptionalCXXScopeSpecifier fail"); CCLoc = ConsumeToken(); } else { assert(SS.isEmpty() && "missing last component of nested name specifier"); FirstTypeName.setIdentifier(nullptr, SourceLocation()); } // Parse the tilde. assert(Tok.is(tok::tilde) && "ParseOptionalCXXScopeSpecifier fail"); SourceLocation TildeLoc = ConsumeToken(); if (Tok.is(tok::kw_decltype) && !FirstTypeName.isValid()) { DeclSpec DS(AttrFactory); ParseDecltypeSpecifier(DS); if (DS.getTypeSpecType() == TST_error) return ExprError(); return Actions.ActOnPseudoDestructorExpr(getCurScope(), Base, OpLoc, OpKind, TildeLoc, DS); } if (!Tok.is(tok::identifier)) { Diag(Tok, diag::err_destructor_tilde_identifier); return ExprError(); } // Parse the second type. UnqualifiedId SecondTypeName; IdentifierInfo *Name = Tok.getIdentifierInfo(); SourceLocation NameLoc = ConsumeToken(); SecondTypeName.setIdentifier(Name, NameLoc); // If there is a '<', the second type name is a template-id. Parse // it as such. // // FIXME: This is not a context in which a '<' is assumed to start a template // argument list. This affects examples such as // void f(auto *p) { p->~X(); } // ... but there's no ambiguity, and nowhere to write 'template' in such an // example, so we accept it anyway. if (Tok.is(tok::less) && ParseUnqualifiedIdTemplateId( SS, ObjectType, Base && Base->containsErrors(), SourceLocation(), Name, NameLoc, false, SecondTypeName, /*AssumeTemplateId=*/true)) return ExprError(); return Actions.ActOnPseudoDestructorExpr(getCurScope(), Base, OpLoc, OpKind, SS, FirstTypeName, CCLoc, TildeLoc, SecondTypeName); } /// ParseCXXBoolLiteral - This handles the C++ Boolean literals. /// /// boolean-literal: [C++ 2.13.5] /// 'true' /// 'false' ExprResult Parser::ParseCXXBoolLiteral() { tok::TokenKind Kind = Tok.getKind(); return Actions.ActOnCXXBoolLiteral(ConsumeToken(), Kind); } /// ParseThrowExpression - This handles the C++ throw expression. /// /// throw-expression: [C++ 15] /// 'throw' assignment-expression[opt] ExprResult Parser::ParseThrowExpression() { assert(Tok.is(tok::kw_throw) && "Not throw!"); SourceLocation ThrowLoc = ConsumeToken(); // Eat the throw token. // If the current token isn't the start of an assignment-expression, // then the expression is not present. This handles things like: // "C ? throw : (void)42", which is crazy but legal. switch (Tok.getKind()) { // FIXME: move this predicate somewhere common. case tok::semi: case tok::r_paren: case tok::r_square: case tok::r_brace: case tok::colon: case tok::comma: return Actions.ActOnCXXThrow(getCurScope(), ThrowLoc, nullptr); default: ExprResult Expr(ParseAssignmentExpression()); if (Expr.isInvalid()) return Expr; return Actions.ActOnCXXThrow(getCurScope(), ThrowLoc, Expr.get()); } } /// Parse the C++ Coroutines co_yield expression. /// /// co_yield-expression: /// 'co_yield' assignment-expression[opt] ExprResult Parser::ParseCoyieldExpression() { assert(Tok.is(tok::kw_co_yield) && "Not co_yield!"); SourceLocation Loc = ConsumeToken(); ExprResult Expr = Tok.is(tok::l_brace) ? ParseBraceInitializer() : ParseAssignmentExpression(); if (!Expr.isInvalid()) Expr = Actions.ActOnCoyieldExpr(getCurScope(), Loc, Expr.get()); return Expr; } /// ParseCXXThis - This handles the C++ 'this' pointer. /// /// C++ 9.3.2: In the body of a non-static member function, the keyword this is /// a non-lvalue expression whose value is the address of the object for which /// the function is called. ExprResult Parser::ParseCXXThis() { assert(Tok.is(tok::kw_this) && "Not 'this'!"); SourceLocation ThisLoc = ConsumeToken(); return Actions.ActOnCXXThis(ThisLoc); } /// ParseCXXTypeConstructExpression - Parse construction of a specified type. /// Can be interpreted either as function-style casting ("int(x)") /// or class type construction ("ClassType(x,y,z)") /// or creation of a value-initialized type ("int()"). /// See [C++ 5.2.3]. /// /// postfix-expression: [C++ 5.2p1] /// simple-type-specifier '(' expression-list[opt] ')' /// [C++0x] simple-type-specifier braced-init-list /// typename-specifier '(' expression-list[opt] ')' /// [C++0x] typename-specifier braced-init-list /// /// In C++1z onwards, the type specifier can also be a template-name. ExprResult Parser::ParseCXXTypeConstructExpression(const DeclSpec &DS) { Declarator DeclaratorInfo(DS, DeclaratorContext::FunctionalCast); ParsedType TypeRep = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo).get(); assert((Tok.is(tok::l_paren) || (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace))) && "Expected '(' or '{'!"); if (Tok.is(tok::l_brace)) { PreferredType.enterTypeCast(Tok.getLocation(), TypeRep.get()); ExprResult Init = ParseBraceInitializer(); if (Init.isInvalid()) return Init; Expr *InitList = Init.get(); return Actions.ActOnCXXTypeConstructExpr( TypeRep, InitList->getBeginLoc(), MultiExprArg(&InitList, 1), InitList->getEndLoc(), /*ListInitialization=*/true); } else { BalancedDelimiterTracker T(*this, tok::l_paren); T.consumeOpen(); PreferredType.enterTypeCast(Tok.getLocation(), TypeRep.get()); ExprVector Exprs; CommaLocsTy CommaLocs; auto RunSignatureHelp = [&]() { QualType PreferredType; if (TypeRep) PreferredType = Actions.ProduceConstructorSignatureHelp( getCurScope(), TypeRep.get()->getCanonicalTypeInternal(), DS.getEndLoc(), Exprs, T.getOpenLocation()); CalledSignatureHelp = true; return PreferredType; }; if (Tok.isNot(tok::r_paren)) { if (ParseExpressionList(Exprs, CommaLocs, [&] { PreferredType.enterFunctionArgument(Tok.getLocation(), RunSignatureHelp); })) { if (PP.isCodeCompletionReached() && !CalledSignatureHelp) RunSignatureHelp(); SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } } // Match the ')'. T.consumeClose(); // TypeRep could be null, if it references an invalid typedef. if (!TypeRep) return ExprError(); assert((Exprs.size() == 0 || Exprs.size()-1 == CommaLocs.size())&& "Unexpected number of commas!"); return Actions.ActOnCXXTypeConstructExpr(TypeRep, T.getOpenLocation(), Exprs, T.getCloseLocation(), /*ListInitialization=*/false); } } /// ParseCXXCondition - if/switch/while condition expression. /// /// condition: /// expression /// type-specifier-seq declarator '=' assignment-expression /// [C++11] type-specifier-seq declarator '=' initializer-clause /// [C++11] type-specifier-seq declarator braced-init-list /// [Clang] type-specifier-seq ref-qualifier[opt] '[' identifier-list ']' /// brace-or-equal-initializer /// [GNU] type-specifier-seq declarator simple-asm-expr[opt] attributes[opt] /// '=' assignment-expression /// /// In C++1z, a condition may in some contexts be preceded by an /// optional init-statement. This function will parse that too. /// /// \param InitStmt If non-null, an init-statement is permitted, and if present /// will be parsed and stored here. /// /// \param Loc The location of the start of the statement that requires this /// condition, e.g., the "for" in a for loop. /// /// \param FRI If non-null, a for range declaration is permitted, and if /// present will be parsed and stored here, and a null result will be returned. /// /// \param EnterForConditionScope If true, enter a continue/break scope at the /// appropriate moment for a 'for' loop. /// /// \returns The parsed condition. Sema::ConditionResult Parser::ParseCXXCondition(StmtResult *InitStmt, SourceLocation Loc, Sema::ConditionKind CK, ForRangeInfo *FRI, bool EnterForConditionScope) { // Helper to ensure we always enter a continue/break scope if requested. struct ForConditionScopeRAII { Scope *S; void enter(bool IsConditionVariable) { if (S) { S->AddFlags(Scope::BreakScope | Scope::ContinueScope); S->setIsConditionVarScope(IsConditionVariable); } } ~ForConditionScopeRAII() { if (S) S->setIsConditionVarScope(false); } } ForConditionScope{EnterForConditionScope ? getCurScope() : nullptr}; ParenBraceBracketBalancer BalancerRAIIObj(*this); PreferredType.enterCondition(Actions, Tok.getLocation()); if (Tok.is(tok::code_completion)) { cutOffParsing(); Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Condition); return Sema::ConditionError(); } ParsedAttributesWithRange attrs(AttrFactory); MaybeParseCXX11Attributes(attrs); const auto WarnOnInit = [this, &CK] { Diag(Tok.getLocation(), getLangOpts().CPlusPlus17 ? diag::warn_cxx14_compat_init_statement : diag::ext_init_statement) << (CK == Sema::ConditionKind::Switch); }; // Determine what kind of thing we have. switch (isCXXConditionDeclarationOrInitStatement(InitStmt, FRI)) { case ConditionOrInitStatement::Expression: { // If this is a for loop, we're entering its condition. ForConditionScope.enter(/*IsConditionVariable=*/false); ProhibitAttributes(attrs); // We can have an empty expression here. // if (; true); if (InitStmt && Tok.is(tok::semi)) { WarnOnInit(); SourceLocation SemiLoc = Tok.getLocation(); if (!Tok.hasLeadingEmptyMacro() && !SemiLoc.isMacroID()) { Diag(SemiLoc, diag::warn_empty_init_statement) << (CK == Sema::ConditionKind::Switch) << FixItHint::CreateRemoval(SemiLoc); } ConsumeToken(); *InitStmt = Actions.ActOnNullStmt(SemiLoc); return ParseCXXCondition(nullptr, Loc, CK); } // Parse the expression. ExprResult Expr = ParseExpression(); // expression if (Expr.isInvalid()) return Sema::ConditionError(); if (InitStmt && Tok.is(tok::semi)) { WarnOnInit(); *InitStmt = Actions.ActOnExprStmt(Expr.get()); ConsumeToken(); return ParseCXXCondition(nullptr, Loc, CK); } return Actions.ActOnCondition(getCurScope(), Loc, Expr.get(), CK); } case ConditionOrInitStatement::InitStmtDecl: { WarnOnInit(); SourceLocation DeclStart = Tok.getLocation(), DeclEnd; DeclGroupPtrTy DG = ParseSimpleDeclaration( DeclaratorContext::SelectionInit, DeclEnd, attrs, /*RequireSemi=*/true); *InitStmt = Actions.ActOnDeclStmt(DG, DeclStart, DeclEnd); return ParseCXXCondition(nullptr, Loc, CK); } case ConditionOrInitStatement::ForRangeDecl: { // This is 'for (init-stmt; for-range-decl : range-expr)'. // We're not actually in a for loop yet, so 'break' and 'continue' aren't // permitted here. assert(FRI && "should not parse a for range declaration here"); SourceLocation DeclStart = Tok.getLocation(), DeclEnd; DeclGroupPtrTy DG = ParseSimpleDeclaration(DeclaratorContext::ForInit, DeclEnd, attrs, false, FRI); FRI->LoopVar = Actions.ActOnDeclStmt(DG, DeclStart, Tok.getLocation()); assert((FRI->ColonLoc.isValid() || !DG) && "cannot find for range declaration"); return Sema::ConditionResult(); } case ConditionOrInitStatement::ConditionDecl: case ConditionOrInitStatement::Error: break; } // If this is a for loop, we're entering its condition. ForConditionScope.enter(/*IsConditionVariable=*/true); // type-specifier-seq DeclSpec DS(AttrFactory); DS.takeAttributesFrom(attrs); ParseSpecifierQualifierList(DS, AS_none, DeclSpecContext::DSC_condition); // declarator Declarator DeclaratorInfo(DS, DeclaratorContext::Condition); ParseDeclarator(DeclaratorInfo); // simple-asm-expr[opt] if (Tok.is(tok::kw_asm)) { SourceLocation Loc; ExprResult AsmLabel(ParseSimpleAsm(/*ForAsmLabel*/ true, &Loc)); if (AsmLabel.isInvalid()) { SkipUntil(tok::semi, StopAtSemi); return Sema::ConditionError(); } DeclaratorInfo.setAsmLabel(AsmLabel.get()); DeclaratorInfo.SetRangeEnd(Loc); } // If attributes are present, parse them. MaybeParseGNUAttributes(DeclaratorInfo); // Type-check the declaration itself. DeclResult Dcl = Actions.ActOnCXXConditionDeclaration(getCurScope(), DeclaratorInfo); if (Dcl.isInvalid()) return Sema::ConditionError(); Decl *DeclOut = Dcl.get(); // '=' assignment-expression // If a '==' or '+=' is found, suggest a fixit to '='. bool CopyInitialization = isTokenEqualOrEqualTypo(); if (CopyInitialization) ConsumeToken(); ExprResult InitExpr = ExprError(); if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) { Diag(Tok.getLocation(), diag::warn_cxx98_compat_generalized_initializer_lists); InitExpr = ParseBraceInitializer(); } else if (CopyInitialization) { PreferredType.enterVariableInit(Tok.getLocation(), DeclOut); InitExpr = ParseAssignmentExpression(); } else if (Tok.is(tok::l_paren)) { // This was probably an attempt to initialize the variable. SourceLocation LParen = ConsumeParen(), RParen = LParen; if (SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch)) RParen = ConsumeParen(); Diag(DeclOut->getLocation(), diag::err_expected_init_in_condition_lparen) << SourceRange(LParen, RParen); } else { Diag(DeclOut->getLocation(), diag::err_expected_init_in_condition); } if (!InitExpr.isInvalid()) Actions.AddInitializerToDecl(DeclOut, InitExpr.get(), !CopyInitialization); else Actions.ActOnInitializerError(DeclOut); Actions.FinalizeDeclaration(DeclOut); return Actions.ActOnConditionVariable(DeclOut, Loc, CK); } /// ParseCXXSimpleTypeSpecifier - [C++ 7.1.5.2] Simple type specifiers. /// This should only be called when the current token is known to be part of /// simple-type-specifier. /// /// simple-type-specifier: /// '::'[opt] nested-name-specifier[opt] type-name /// '::'[opt] nested-name-specifier 'template' simple-template-id [TODO] /// char /// wchar_t /// bool /// short /// int /// long /// signed /// unsigned /// float /// double /// void /// [GNU] typeof-specifier /// [C++0x] auto [TODO] /// /// type-name: /// class-name /// enum-name /// typedef-name /// void Parser::ParseCXXSimpleTypeSpecifier(DeclSpec &DS) { DS.SetRangeStart(Tok.getLocation()); const char *PrevSpec; unsigned DiagID; SourceLocation Loc = Tok.getLocation(); const clang::PrintingPolicy &Policy = Actions.getASTContext().getPrintingPolicy(); switch (Tok.getKind()) { case tok::identifier: // foo::bar case tok::coloncolon: // ::foo::bar llvm_unreachable("Annotation token should already be formed!"); default: llvm_unreachable("Not a simple-type-specifier token!"); // type-name case tok::annot_typename: { DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec, DiagID, getTypeAnnotation(Tok), Policy); DS.SetRangeEnd(Tok.getAnnotationEndLoc()); ConsumeAnnotationToken(); DS.Finish(Actions, Policy); return; } case tok::kw__ExtInt: { ExprResult ER = ParseExtIntegerArgument(); if (ER.isInvalid()) DS.SetTypeSpecError(); else DS.SetExtIntType(Loc, ER.get(), PrevSpec, DiagID, Policy); // Do this here because we have already consumed the close paren. DS.SetRangeEnd(PrevTokLocation); DS.Finish(Actions, Policy); return; } // builtin types case tok::kw_short: DS.SetTypeSpecWidth(TypeSpecifierWidth::Short, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_long: DS.SetTypeSpecWidth(TypeSpecifierWidth::Long, Loc, PrevSpec, DiagID, Policy); break; case tok::kw___int64: DS.SetTypeSpecWidth(TypeSpecifierWidth::LongLong, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_signed: DS.SetTypeSpecSign(TypeSpecifierSign::Signed, Loc, PrevSpec, DiagID); break; case tok::kw_unsigned: DS.SetTypeSpecSign(TypeSpecifierSign::Unsigned, Loc, PrevSpec, DiagID); break; case tok::kw_void: DS.SetTypeSpecType(DeclSpec::TST_void, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_char: DS.SetTypeSpecType(DeclSpec::TST_char, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_int: DS.SetTypeSpecType(DeclSpec::TST_int, Loc, PrevSpec, DiagID, Policy); break; case tok::kw___int128: DS.SetTypeSpecType(DeclSpec::TST_int128, Loc, PrevSpec, DiagID, Policy); break; case tok::kw___bf16: DS.SetTypeSpecType(DeclSpec::TST_BFloat16, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_half: DS.SetTypeSpecType(DeclSpec::TST_half, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_float: DS.SetTypeSpecType(DeclSpec::TST_float, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_double: DS.SetTypeSpecType(DeclSpec::TST_double, Loc, PrevSpec, DiagID, Policy); break; case tok::kw__Float16: DS.SetTypeSpecType(DeclSpec::TST_float16, Loc, PrevSpec, DiagID, Policy); break; case tok::kw___float128: DS.SetTypeSpecType(DeclSpec::TST_float128, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_wchar_t: DS.SetTypeSpecType(DeclSpec::TST_wchar, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_char8_t: DS.SetTypeSpecType(DeclSpec::TST_char8, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_char16_t: DS.SetTypeSpecType(DeclSpec::TST_char16, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_char32_t: DS.SetTypeSpecType(DeclSpec::TST_char32, Loc, PrevSpec, DiagID, Policy); break; case tok::kw_bool: DS.SetTypeSpecType(DeclSpec::TST_bool, Loc, PrevSpec, DiagID, Policy); break; #define GENERIC_IMAGE_TYPE(ImgType, Id) \ case tok::kw_##ImgType##_t: \ DS.SetTypeSpecType(DeclSpec::TST_##ImgType##_t, Loc, PrevSpec, DiagID, \ Policy); \ break; #include "clang/Basic/OpenCLImageTypes.def" case tok::annot_decltype: case tok::kw_decltype: DS.SetRangeEnd(ParseDecltypeSpecifier(DS)); return DS.Finish(Actions, Policy); // GNU typeof support. case tok::kw_typeof: ParseTypeofSpecifier(DS); DS.Finish(Actions, Policy); return; } ConsumeAnyToken(); DS.SetRangeEnd(PrevTokLocation); DS.Finish(Actions, Policy); } /// ParseCXXTypeSpecifierSeq - Parse a C++ type-specifier-seq (C++ /// [dcl.name]), which is a non-empty sequence of type-specifiers, /// e.g., "const short int". Note that the DeclSpec is *not* finished /// by parsing the type-specifier-seq, because these sequences are /// typically followed by some form of declarator. Returns true and /// emits diagnostics if this is not a type-specifier-seq, false /// otherwise. /// /// type-specifier-seq: [C++ 8.1] /// type-specifier type-specifier-seq[opt] /// bool Parser::ParseCXXTypeSpecifierSeq(DeclSpec &DS) { ParseSpecifierQualifierList(DS, AS_none, DeclSpecContext::DSC_type_specifier); DS.Finish(Actions, Actions.getASTContext().getPrintingPolicy()); return false; } /// Finish parsing a C++ unqualified-id that is a template-id of /// some form. /// /// This routine is invoked when a '<' is encountered after an identifier or /// operator-function-id is parsed by \c ParseUnqualifiedId() to determine /// whether the unqualified-id is actually a template-id. This routine will /// then parse the template arguments and form the appropriate template-id to /// return to the caller. /// /// \param SS the nested-name-specifier that precedes this template-id, if /// we're actually parsing a qualified-id. /// /// \param ObjectType if this unqualified-id occurs within a member access /// expression, the type of the base object whose member is being accessed. /// /// \param ObjectHadErrors this unqualified-id occurs within a member access /// expression, indicates whether the original subexpressions had any errors. /// /// \param Name for constructor and destructor names, this is the actual /// identifier that may be a template-name. /// /// \param NameLoc the location of the class-name in a constructor or /// destructor. /// /// \param EnteringContext whether we're entering the scope of the /// nested-name-specifier. /// /// \param Id as input, describes the template-name or operator-function-id /// that precedes the '<'. If template arguments were parsed successfully, /// will be updated with the template-id. /// /// \param AssumeTemplateId When true, this routine will assume that the name /// refers to a template without performing name lookup to verify. /// /// \returns true if a parse error occurred, false otherwise. bool Parser::ParseUnqualifiedIdTemplateId( CXXScopeSpec &SS, ParsedType ObjectType, bool ObjectHadErrors, SourceLocation TemplateKWLoc, IdentifierInfo *Name, SourceLocation NameLoc, bool EnteringContext, UnqualifiedId &Id, bool AssumeTemplateId) { assert(Tok.is(tok::less) && "Expected '<' to finish parsing a template-id"); TemplateTy Template; TemplateNameKind TNK = TNK_Non_template; switch (Id.getKind()) { case UnqualifiedIdKind::IK_Identifier: case UnqualifiedIdKind::IK_OperatorFunctionId: case UnqualifiedIdKind::IK_LiteralOperatorId: if (AssumeTemplateId) { // We defer the injected-class-name checks until we've found whether // this template-id is used to form a nested-name-specifier or not. TNK = Actions.ActOnTemplateName(getCurScope(), SS, TemplateKWLoc, Id, ObjectType, EnteringContext, Template, /*AllowInjectedClassName*/ true); } else { bool MemberOfUnknownSpecialization; TNK = Actions.isTemplateName(getCurScope(), SS, TemplateKWLoc.isValid(), Id, ObjectType, EnteringContext, Template, MemberOfUnknownSpecialization); // If lookup found nothing but we're assuming that this is a template // name, double-check that makes sense syntactically before committing // to it. if (TNK == TNK_Undeclared_template && isTemplateArgumentList(0) == TPResult::False) return false; if (TNK == TNK_Non_template && MemberOfUnknownSpecialization && ObjectType && isTemplateArgumentList(0) == TPResult::True) { // If we had errors before, ObjectType can be dependent even without any // templates, do not report missing template keyword in that case. if (!ObjectHadErrors) { // We have something like t->getAs(), where getAs is a // member of an unknown specialization. However, this will only // parse correctly as a template, so suggest the keyword 'template' // before 'getAs' and treat this as a dependent template name. std::string Name; if (Id.getKind() == UnqualifiedIdKind::IK_Identifier) Name = std::string(Id.Identifier->getName()); else { Name = "operator "; if (Id.getKind() == UnqualifiedIdKind::IK_OperatorFunctionId) Name += getOperatorSpelling(Id.OperatorFunctionId.Operator); else Name += Id.Identifier->getName(); } Diag(Id.StartLocation, diag::err_missing_dependent_template_keyword) << Name << FixItHint::CreateInsertion(Id.StartLocation, "template "); } TNK = Actions.ActOnTemplateName( getCurScope(), SS, TemplateKWLoc, Id, ObjectType, EnteringContext, Template, /*AllowInjectedClassName*/ true); } else if (TNK == TNK_Non_template) { return false; } } break; case UnqualifiedIdKind::IK_ConstructorName: { UnqualifiedId TemplateName; bool MemberOfUnknownSpecialization; TemplateName.setIdentifier(Name, NameLoc); TNK = Actions.isTemplateName(getCurScope(), SS, TemplateKWLoc.isValid(), TemplateName, ObjectType, EnteringContext, Template, MemberOfUnknownSpecialization); if (TNK == TNK_Non_template) return false; break; } case UnqualifiedIdKind::IK_DestructorName: { UnqualifiedId TemplateName; bool MemberOfUnknownSpecialization; TemplateName.setIdentifier(Name, NameLoc); if (ObjectType) { TNK = Actions.ActOnTemplateName( getCurScope(), SS, TemplateKWLoc, TemplateName, ObjectType, EnteringContext, Template, /*AllowInjectedClassName*/ true); } else { TNK = Actions.isTemplateName(getCurScope(), SS, TemplateKWLoc.isValid(), TemplateName, ObjectType, EnteringContext, Template, MemberOfUnknownSpecialization); if (TNK == TNK_Non_template && !Id.DestructorName.get()) { Diag(NameLoc, diag::err_destructor_template_id) << Name << SS.getRange(); // Carry on to parse the template arguments before bailing out. } } break; } default: return false; } // Parse the enclosed template argument list. SourceLocation LAngleLoc, RAngleLoc; TemplateArgList TemplateArgs; if (ParseTemplateIdAfterTemplateName(true, LAngleLoc, TemplateArgs, RAngleLoc)) return true; // If this is a non-template, we already issued a diagnostic. if (TNK == TNK_Non_template) return true; if (Id.getKind() == UnqualifiedIdKind::IK_Identifier || Id.getKind() == UnqualifiedIdKind::IK_OperatorFunctionId || Id.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId) { // Form a parsed representation of the template-id to be stored in the // UnqualifiedId. // FIXME: Store name for literal operator too. IdentifierInfo *TemplateII = Id.getKind() == UnqualifiedIdKind::IK_Identifier ? Id.Identifier : nullptr; OverloadedOperatorKind OpKind = Id.getKind() == UnqualifiedIdKind::IK_Identifier ? OO_None : Id.OperatorFunctionId.Operator; TemplateIdAnnotation *TemplateId = TemplateIdAnnotation::Create( TemplateKWLoc, Id.StartLocation, TemplateII, OpKind, Template, TNK, LAngleLoc, RAngleLoc, TemplateArgs, /*ArgsInvalid*/false, TemplateIds); Id.setTemplateId(TemplateId); return false; } // Bundle the template arguments together. ASTTemplateArgsPtr TemplateArgsPtr(TemplateArgs); // Constructor and destructor names. TypeResult Type = Actions.ActOnTemplateIdType( getCurScope(), SS, TemplateKWLoc, Template, Name, NameLoc, LAngleLoc, TemplateArgsPtr, RAngleLoc, /*IsCtorOrDtorName=*/true); if (Type.isInvalid()) return true; if (Id.getKind() == UnqualifiedIdKind::IK_ConstructorName) Id.setConstructorName(Type.get(), NameLoc, RAngleLoc); else Id.setDestructorName(Id.StartLocation, Type.get(), RAngleLoc); return false; } /// Parse an operator-function-id or conversion-function-id as part /// of a C++ unqualified-id. /// /// This routine is responsible only for parsing the operator-function-id or /// conversion-function-id; it does not handle template arguments in any way. /// /// \code /// operator-function-id: [C++ 13.5] /// 'operator' operator /// /// operator: one of /// new delete new[] delete[] /// + - * / % ^ & | ~ /// ! = < > += -= *= /= %= /// ^= &= |= << >> >>= <<= == != /// <= >= && || ++ -- , ->* -> /// () [] <=> /// /// conversion-function-id: [C++ 12.3.2] /// operator conversion-type-id /// /// conversion-type-id: /// type-specifier-seq conversion-declarator[opt] /// /// conversion-declarator: /// ptr-operator conversion-declarator[opt] /// \endcode /// /// \param SS The nested-name-specifier that preceded this unqualified-id. If /// non-empty, then we are parsing the unqualified-id of a qualified-id. /// /// \param EnteringContext whether we are entering the scope of the /// nested-name-specifier. /// /// \param ObjectType if this unqualified-id occurs within a member access /// expression, the type of the base object whose member is being accessed. /// /// \param Result on a successful parse, contains the parsed unqualified-id. /// /// \returns true if parsing fails, false otherwise. bool Parser::ParseUnqualifiedIdOperator(CXXScopeSpec &SS, bool EnteringContext, ParsedType ObjectType, UnqualifiedId &Result) { assert(Tok.is(tok::kw_operator) && "Expected 'operator' keyword"); // Consume the 'operator' keyword. SourceLocation KeywordLoc = ConsumeToken(); // Determine what kind of operator name we have. unsigned SymbolIdx = 0; SourceLocation SymbolLocations[3]; OverloadedOperatorKind Op = OO_None; switch (Tok.getKind()) { case tok::kw_new: case tok::kw_delete: { bool isNew = Tok.getKind() == tok::kw_new; // Consume the 'new' or 'delete'. SymbolLocations[SymbolIdx++] = ConsumeToken(); // Check for array new/delete. if (Tok.is(tok::l_square) && (!getLangOpts().CPlusPlus11 || NextToken().isNot(tok::l_square))) { // Consume the '[' and ']'. BalancedDelimiterTracker T(*this, tok::l_square); T.consumeOpen(); T.consumeClose(); if (T.getCloseLocation().isInvalid()) return true; SymbolLocations[SymbolIdx++] = T.getOpenLocation(); SymbolLocations[SymbolIdx++] = T.getCloseLocation(); Op = isNew? OO_Array_New : OO_Array_Delete; } else { Op = isNew? OO_New : OO_Delete; } break; } #define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ case tok::Token: \ SymbolLocations[SymbolIdx++] = ConsumeToken(); \ Op = OO_##Name; \ break; #define OVERLOADED_OPERATOR_MULTI(Name,Spelling,Unary,Binary,MemberOnly) #include "clang/Basic/OperatorKinds.def" case tok::l_paren: { // Consume the '(' and ')'. BalancedDelimiterTracker T(*this, tok::l_paren); T.consumeOpen(); T.consumeClose(); if (T.getCloseLocation().isInvalid()) return true; SymbolLocations[SymbolIdx++] = T.getOpenLocation(); SymbolLocations[SymbolIdx++] = T.getCloseLocation(); Op = OO_Call; break; } case tok::l_square: { // Consume the '[' and ']'. BalancedDelimiterTracker T(*this, tok::l_square); T.consumeOpen(); T.consumeClose(); if (T.getCloseLocation().isInvalid()) return true; SymbolLocations[SymbolIdx++] = T.getOpenLocation(); SymbolLocations[SymbolIdx++] = T.getCloseLocation(); Op = OO_Subscript; break; } case tok::code_completion: { // Don't try to parse any further. cutOffParsing(); // Code completion for the operator name. Actions.CodeCompleteOperatorName(getCurScope()); return true; } default: break; } if (Op != OO_None) { // We have parsed an operator-function-id. Result.setOperatorFunctionId(KeywordLoc, Op, SymbolLocations); return false; } // Parse a literal-operator-id. // // literal-operator-id: C++11 [over.literal] // operator string-literal identifier // operator user-defined-string-literal if (getLangOpts().CPlusPlus11 && isTokenStringLiteral()) { Diag(Tok.getLocation(), diag::warn_cxx98_compat_literal_operator); SourceLocation DiagLoc; unsigned DiagId = 0; // We're past translation phase 6, so perform string literal concatenation // before checking for "". SmallVector Toks; SmallVector TokLocs; while (isTokenStringLiteral()) { if (!Tok.is(tok::string_literal) && !DiagId) { // C++11 [over.literal]p1: // The string-literal or user-defined-string-literal in a // literal-operator-id shall have no encoding-prefix [...]. DiagLoc = Tok.getLocation(); DiagId = diag::err_literal_operator_string_prefix; } Toks.push_back(Tok); TokLocs.push_back(ConsumeStringToken()); } StringLiteralParser Literal(Toks, PP); if (Literal.hadError) return true; // Grab the literal operator's suffix, which will be either the next token // or a ud-suffix from the string literal. IdentifierInfo *II = nullptr; SourceLocation SuffixLoc; if (!Literal.getUDSuffix().empty()) { II = &PP.getIdentifierTable().get(Literal.getUDSuffix()); SuffixLoc = Lexer::AdvanceToTokenCharacter(TokLocs[Literal.getUDSuffixToken()], Literal.getUDSuffixOffset(), PP.getSourceManager(), getLangOpts()); } else if (Tok.is(tok::identifier)) { II = Tok.getIdentifierInfo(); SuffixLoc = ConsumeToken(); TokLocs.push_back(SuffixLoc); } else { Diag(Tok.getLocation(), diag::err_expected) << tok::identifier; return true; } // The string literal must be empty. if (!Literal.GetString().empty() || Literal.Pascal) { // C++11 [over.literal]p1: // The string-literal or user-defined-string-literal in a // literal-operator-id shall [...] contain no characters // other than the implicit terminating '\0'. DiagLoc = TokLocs.front(); DiagId = diag::err_literal_operator_string_not_empty; } if (DiagId) { // This isn't a valid literal-operator-id, but we think we know // what the user meant. Tell them what they should have written. SmallString<32> Str; Str += "\"\""; Str += II->getName(); Diag(DiagLoc, DiagId) << FixItHint::CreateReplacement( SourceRange(TokLocs.front(), TokLocs.back()), Str); } Result.setLiteralOperatorId(II, KeywordLoc, SuffixLoc); return Actions.checkLiteralOperatorId(SS, Result); } // Parse a conversion-function-id. // // conversion-function-id: [C++ 12.3.2] // operator conversion-type-id // // conversion-type-id: // type-specifier-seq conversion-declarator[opt] // // conversion-declarator: // ptr-operator conversion-declarator[opt] // Parse the type-specifier-seq. DeclSpec DS(AttrFactory); if (ParseCXXTypeSpecifierSeq(DS)) // FIXME: ObjectType? return true; // Parse the conversion-declarator, which is merely a sequence of // ptr-operators. Declarator D(DS, DeclaratorContext::ConversionId); ParseDeclaratorInternal(D, /*DirectDeclParser=*/nullptr); // Finish up the type. TypeResult Ty = Actions.ActOnTypeName(getCurScope(), D); if (Ty.isInvalid()) return true; // Note that this is a conversion-function-id. Result.setConversionFunctionId(KeywordLoc, Ty.get(), D.getSourceRange().getEnd()); return false; } /// Parse a C++ unqualified-id (or a C identifier), which describes the /// name of an entity. /// /// \code /// unqualified-id: [C++ expr.prim.general] /// identifier /// operator-function-id /// conversion-function-id /// [C++0x] literal-operator-id [TODO] /// ~ class-name /// template-id /// /// \endcode /// /// \param SS The nested-name-specifier that preceded this unqualified-id. If /// non-empty, then we are parsing the unqualified-id of a qualified-id. /// /// \param ObjectType if this unqualified-id occurs within a member access /// expression, the type of the base object whose member is being accessed. /// /// \param ObjectHadErrors if this unqualified-id occurs within a member access /// expression, indicates whether the original subexpressions had any errors. /// When true, diagnostics for missing 'template' keyword will be supressed. /// /// \param EnteringContext whether we are entering the scope of the /// nested-name-specifier. /// /// \param AllowDestructorName whether we allow parsing of a destructor name. /// /// \param AllowConstructorName whether we allow parsing a constructor name. /// /// \param AllowDeductionGuide whether we allow parsing a deduction guide name. /// /// \param Result on a successful parse, contains the parsed unqualified-id. /// /// \returns true if parsing fails, false otherwise. bool Parser::ParseUnqualifiedId(CXXScopeSpec &SS, ParsedType ObjectType, bool ObjectHadErrors, bool EnteringContext, bool AllowDestructorName, bool AllowConstructorName, bool AllowDeductionGuide, SourceLocation *TemplateKWLoc, UnqualifiedId &Result) { if (TemplateKWLoc) *TemplateKWLoc = SourceLocation(); // Handle 'A::template B'. This is for template-ids which have not // already been annotated by ParseOptionalCXXScopeSpecifier(). bool TemplateSpecified = false; if (Tok.is(tok::kw_template)) { if (TemplateKWLoc && (ObjectType || SS.isSet())) { TemplateSpecified = true; *TemplateKWLoc = ConsumeToken(); } else { SourceLocation TemplateLoc = ConsumeToken(); Diag(TemplateLoc, diag::err_unexpected_template_in_unqualified_id) << FixItHint::CreateRemoval(TemplateLoc); } } // unqualified-id: // identifier // template-id (when it hasn't already been annotated) if (Tok.is(tok::identifier)) { // Consume the identifier. IdentifierInfo *Id = Tok.getIdentifierInfo(); SourceLocation IdLoc = ConsumeToken(); if (!getLangOpts().CPlusPlus) { // If we're not in C++, only identifiers matter. Record the // identifier and return. Result.setIdentifier(Id, IdLoc); return false; } ParsedTemplateTy TemplateName; if (AllowConstructorName && Actions.isCurrentClassName(*Id, getCurScope(), &SS)) { // We have parsed a constructor name. ParsedType Ty = Actions.getConstructorName(*Id, IdLoc, getCurScope(), SS, EnteringContext); if (!Ty) return true; Result.setConstructorName(Ty, IdLoc, IdLoc); } else if (getLangOpts().CPlusPlus17 && AllowDeductionGuide && SS.isEmpty() && Actions.isDeductionGuideName(getCurScope(), *Id, IdLoc, &TemplateName)) { // We have parsed a template-name naming a deduction guide. Result.setDeductionGuideName(TemplateName, IdLoc); } else { // We have parsed an identifier. Result.setIdentifier(Id, IdLoc); } // If the next token is a '<', we may have a template. TemplateTy Template; if (Tok.is(tok::less)) return ParseUnqualifiedIdTemplateId( SS, ObjectType, ObjectHadErrors, TemplateKWLoc ? *TemplateKWLoc : SourceLocation(), Id, IdLoc, EnteringContext, Result, TemplateSpecified); else if (TemplateSpecified && Actions.ActOnTemplateName( getCurScope(), SS, *TemplateKWLoc, Result, ObjectType, EnteringContext, Template, /*AllowInjectedClassName*/ true) == TNK_Non_template) return true; return false; } // unqualified-id: // template-id (already parsed and annotated) if (Tok.is(tok::annot_template_id)) { TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok); // FIXME: Consider passing invalid template-ids on to callers; they may // be able to recover better than we can. if (TemplateId->isInvalid()) { ConsumeAnnotationToken(); return true; } // If the template-name names the current class, then this is a constructor if (AllowConstructorName && TemplateId->Name && Actions.isCurrentClassName(*TemplateId->Name, getCurScope(), &SS)) { if (SS.isSet()) { // C++ [class.qual]p2 specifies that a qualified template-name // is taken as the constructor name where a constructor can be // declared. Thus, the template arguments are extraneous, so // complain about them and remove them entirely. Diag(TemplateId->TemplateNameLoc, diag::err_out_of_line_constructor_template_id) << TemplateId->Name << FixItHint::CreateRemoval( SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc)); ParsedType Ty = Actions.getConstructorName( *TemplateId->Name, TemplateId->TemplateNameLoc, getCurScope(), SS, EnteringContext); if (!Ty) return true; Result.setConstructorName(Ty, TemplateId->TemplateNameLoc, TemplateId->RAngleLoc); ConsumeAnnotationToken(); return false; } Result.setConstructorTemplateId(TemplateId); ConsumeAnnotationToken(); return false; } // We have already parsed a template-id; consume the annotation token as // our unqualified-id. Result.setTemplateId(TemplateId); SourceLocation TemplateLoc = TemplateId->TemplateKWLoc; if (TemplateLoc.isValid()) { if (TemplateKWLoc && (ObjectType || SS.isSet())) *TemplateKWLoc = TemplateLoc; else Diag(TemplateLoc, diag::err_unexpected_template_in_unqualified_id) << FixItHint::CreateRemoval(TemplateLoc); } ConsumeAnnotationToken(); return false; } // unqualified-id: // operator-function-id // conversion-function-id if (Tok.is(tok::kw_operator)) { if (ParseUnqualifiedIdOperator(SS, EnteringContext, ObjectType, Result)) return true; // If we have an operator-function-id or a literal-operator-id and the next // token is a '<', we may have a // // template-id: // operator-function-id < template-argument-list[opt] > TemplateTy Template; if ((Result.getKind() == UnqualifiedIdKind::IK_OperatorFunctionId || Result.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId) && Tok.is(tok::less)) return ParseUnqualifiedIdTemplateId( SS, ObjectType, ObjectHadErrors, TemplateKWLoc ? *TemplateKWLoc : SourceLocation(), nullptr, SourceLocation(), EnteringContext, Result, TemplateSpecified); else if (TemplateSpecified && Actions.ActOnTemplateName( getCurScope(), SS, *TemplateKWLoc, Result, ObjectType, EnteringContext, Template, /*AllowInjectedClassName*/ true) == TNK_Non_template) return true; return false; } if (getLangOpts().CPlusPlus && (AllowDestructorName || SS.isSet()) && Tok.is(tok::tilde)) { // C++ [expr.unary.op]p10: // There is an ambiguity in the unary-expression ~X(), where X is a // class-name. The ambiguity is resolved in favor of treating ~ as a // unary complement rather than treating ~X as referring to a destructor. // Parse the '~'. SourceLocation TildeLoc = ConsumeToken(); if (TemplateSpecified) { // C++ [temp.names]p3: // A name prefixed by the keyword template shall be a template-id [...] // // A template-id cannot begin with a '~' token. This would never work // anyway: x.~A() would specify that the destructor is a template, // not that 'A' is a template. // // FIXME: Suggest replacing the attempted destructor name with a correct // destructor name and recover. (This is not trivial if this would become // a pseudo-destructor name). Diag(*TemplateKWLoc, diag::err_unexpected_template_in_destructor_name) << Tok.getLocation(); return true; } if (SS.isEmpty() && Tok.is(tok::kw_decltype)) { DeclSpec DS(AttrFactory); SourceLocation EndLoc = ParseDecltypeSpecifier(DS); if (ParsedType Type = Actions.getDestructorTypeForDecltype(DS, ObjectType)) { Result.setDestructorName(TildeLoc, Type, EndLoc); return false; } return true; } // Parse the class-name. if (Tok.isNot(tok::identifier)) { Diag(Tok, diag::err_destructor_tilde_identifier); return true; } // If the user wrote ~T::T, correct it to T::~T. DeclaratorScopeObj DeclScopeObj(*this, SS); if (NextToken().is(tok::coloncolon)) { // Don't let ParseOptionalCXXScopeSpecifier() "correct" // `int A; struct { ~A::A(); };` to `int A; struct { ~A:A(); };`, // it will confuse this recovery logic. ColonProtectionRAIIObject ColonRAII(*this, false); if (SS.isSet()) { AnnotateScopeToken(SS, /*NewAnnotation*/true); SS.clear(); } if (ParseOptionalCXXScopeSpecifier(SS, ObjectType, ObjectHadErrors, EnteringContext)) return true; if (SS.isNotEmpty()) ObjectType = nullptr; if (Tok.isNot(tok::identifier) || NextToken().is(tok::coloncolon) || !SS.isSet()) { Diag(TildeLoc, diag::err_destructor_tilde_scope); return true; } // Recover as if the tilde had been written before the identifier. Diag(TildeLoc, diag::err_destructor_tilde_scope) << FixItHint::CreateRemoval(TildeLoc) << FixItHint::CreateInsertion(Tok.getLocation(), "~"); // Temporarily enter the scope for the rest of this function. if (Actions.ShouldEnterDeclaratorScope(getCurScope(), SS)) DeclScopeObj.EnterDeclaratorScope(); } // Parse the class-name (or template-name in a simple-template-id). IdentifierInfo *ClassName = Tok.getIdentifierInfo(); SourceLocation ClassNameLoc = ConsumeToken(); if (Tok.is(tok::less)) { Result.setDestructorName(TildeLoc, nullptr, ClassNameLoc); return ParseUnqualifiedIdTemplateId( SS, ObjectType, ObjectHadErrors, TemplateKWLoc ? *TemplateKWLoc : SourceLocation(), ClassName, ClassNameLoc, EnteringContext, Result, TemplateSpecified); } // Note that this is a destructor name. ParsedType Ty = Actions.getDestructorName(TildeLoc, *ClassName, ClassNameLoc, getCurScope(), SS, ObjectType, EnteringContext); if (!Ty) return true; Result.setDestructorName(TildeLoc, Ty, ClassNameLoc); return false; } Diag(Tok, diag::err_expected_unqualified_id) << getLangOpts().CPlusPlus; return true; } /// ParseCXXNewExpression - Parse a C++ new-expression. New is used to allocate /// memory in a typesafe manner and call constructors. /// /// This method is called to parse the new expression after the optional :: has /// been already parsed. If the :: was present, "UseGlobal" is true and "Start" /// is its location. Otherwise, "Start" is the location of the 'new' token. /// /// new-expression: /// '::'[opt] 'new' new-placement[opt] new-type-id /// new-initializer[opt] /// '::'[opt] 'new' new-placement[opt] '(' type-id ')' /// new-initializer[opt] /// /// new-placement: /// '(' expression-list ')' /// /// new-type-id: /// type-specifier-seq new-declarator[opt] /// [GNU] attributes type-specifier-seq new-declarator[opt] /// /// new-declarator: /// ptr-operator new-declarator[opt] /// direct-new-declarator /// /// new-initializer: /// '(' expression-list[opt] ')' /// [C++0x] braced-init-list /// ExprResult Parser::ParseCXXNewExpression(bool UseGlobal, SourceLocation Start) { assert(Tok.is(tok::kw_new) && "expected 'new' token"); ConsumeToken(); // Consume 'new' // A '(' now can be a new-placement or the '(' wrapping the type-id in the // second form of new-expression. It can't be a new-type-id. ExprVector PlacementArgs; SourceLocation PlacementLParen, PlacementRParen; SourceRange TypeIdParens; DeclSpec DS(AttrFactory); Declarator DeclaratorInfo(DS, DeclaratorContext::CXXNew); if (Tok.is(tok::l_paren)) { // If it turns out to be a placement, we change the type location. BalancedDelimiterTracker T(*this, tok::l_paren); T.consumeOpen(); PlacementLParen = T.getOpenLocation(); if (ParseExpressionListOrTypeId(PlacementArgs, DeclaratorInfo)) { SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch); return ExprError(); } T.consumeClose(); PlacementRParen = T.getCloseLocation(); if (PlacementRParen.isInvalid()) { SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch); return ExprError(); } if (PlacementArgs.empty()) { // Reset the placement locations. There was no placement. TypeIdParens = T.getRange(); PlacementLParen = PlacementRParen = SourceLocation(); } else { // We still need the type. if (Tok.is(tok::l_paren)) { BalancedDelimiterTracker T(*this, tok::l_paren); T.consumeOpen(); MaybeParseGNUAttributes(DeclaratorInfo); ParseSpecifierQualifierList(DS); DeclaratorInfo.SetSourceRange(DS.getSourceRange()); ParseDeclarator(DeclaratorInfo); T.consumeClose(); TypeIdParens = T.getRange(); } else { MaybeParseGNUAttributes(DeclaratorInfo); if (ParseCXXTypeSpecifierSeq(DS)) DeclaratorInfo.setInvalidType(true); else { DeclaratorInfo.SetSourceRange(DS.getSourceRange()); ParseDeclaratorInternal(DeclaratorInfo, &Parser::ParseDirectNewDeclarator); } } } } else { // A new-type-id is a simplified type-id, where essentially the // direct-declarator is replaced by a direct-new-declarator. MaybeParseGNUAttributes(DeclaratorInfo); if (ParseCXXTypeSpecifierSeq(DS)) DeclaratorInfo.setInvalidType(true); else { DeclaratorInfo.SetSourceRange(DS.getSourceRange()); ParseDeclaratorInternal(DeclaratorInfo, &Parser::ParseDirectNewDeclarator); } } if (DeclaratorInfo.isInvalidType()) { SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch); return ExprError(); } ExprResult Initializer; if (Tok.is(tok::l_paren)) { SourceLocation ConstructorLParen, ConstructorRParen; ExprVector ConstructorArgs; BalancedDelimiterTracker T(*this, tok::l_paren); T.consumeOpen(); ConstructorLParen = T.getOpenLocation(); if (Tok.isNot(tok::r_paren)) { CommaLocsTy CommaLocs; auto RunSignatureHelp = [&]() { ParsedType TypeRep = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo).get(); QualType PreferredType; // ActOnTypeName might adjust DeclaratorInfo and return a null type even // the passing DeclaratorInfo is valid, e.g. running SignatureHelp on // `new decltype(invalid) (^)`. if (TypeRep) PreferredType = Actions.ProduceConstructorSignatureHelp( getCurScope(), TypeRep.get()->getCanonicalTypeInternal(), DeclaratorInfo.getEndLoc(), ConstructorArgs, ConstructorLParen); CalledSignatureHelp = true; return PreferredType; }; if (ParseExpressionList(ConstructorArgs, CommaLocs, [&] { PreferredType.enterFunctionArgument(Tok.getLocation(), RunSignatureHelp); })) { if (PP.isCodeCompletionReached() && !CalledSignatureHelp) RunSignatureHelp(); SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch); return ExprError(); } } T.consumeClose(); ConstructorRParen = T.getCloseLocation(); if (ConstructorRParen.isInvalid()) { SkipUntil(tok::semi, StopAtSemi | StopBeforeMatch); return ExprError(); } Initializer = Actions.ActOnParenListExpr(ConstructorLParen, ConstructorRParen, ConstructorArgs); } else if (Tok.is(tok::l_brace) && getLangOpts().CPlusPlus11) { Diag(Tok.getLocation(), diag::warn_cxx98_compat_generalized_initializer_lists); Initializer = ParseBraceInitializer(); } if (Initializer.isInvalid()) return Initializer; return Actions.ActOnCXXNew(Start, UseGlobal, PlacementLParen, PlacementArgs, PlacementRParen, TypeIdParens, DeclaratorInfo, Initializer.get()); } /// ParseDirectNewDeclarator - Parses a direct-new-declarator. Intended to be /// passed to ParseDeclaratorInternal. /// /// direct-new-declarator: /// '[' expression[opt] ']' /// direct-new-declarator '[' constant-expression ']' /// void Parser::ParseDirectNewDeclarator(Declarator &D) { // Parse the array dimensions. bool First = true; while (Tok.is(tok::l_square)) { // An array-size expression can't start with a lambda. if (CheckProhibitedCXX11Attribute()) continue; BalancedDelimiterTracker T(*this, tok::l_square); T.consumeOpen(); ExprResult Size = First ? (Tok.is(tok::r_square) ? ExprResult() : ParseExpression()) : ParseConstantExpression(); if (Size.isInvalid()) { // Recover SkipUntil(tok::r_square, StopAtSemi); return; } First = false; T.consumeClose(); // Attributes here appertain to the array type. C++11 [expr.new]p5. ParsedAttributes Attrs(AttrFactory); MaybeParseCXX11Attributes(Attrs); D.AddTypeInfo(DeclaratorChunk::getArray(0, /*isStatic=*/false, /*isStar=*/false, Size.get(), T.getOpenLocation(), T.getCloseLocation()), std::move(Attrs), T.getCloseLocation()); if (T.getCloseLocation().isInvalid()) return; } } /// ParseExpressionListOrTypeId - Parse either an expression-list or a type-id. /// This ambiguity appears in the syntax of the C++ new operator. /// /// new-expression: /// '::'[opt] 'new' new-placement[opt] '(' type-id ')' /// new-initializer[opt] /// /// new-placement: /// '(' expression-list ')' /// bool Parser::ParseExpressionListOrTypeId( SmallVectorImpl &PlacementArgs, Declarator &D) { // The '(' was already consumed. if (isTypeIdInParens()) { ParseSpecifierQualifierList(D.getMutableDeclSpec()); D.SetSourceRange(D.getDeclSpec().getSourceRange()); ParseDeclarator(D); return D.isInvalidType(); } // It's not a type, it has to be an expression list. // Discard the comma locations - ActOnCXXNew has enough parameters. CommaLocsTy CommaLocs; return ParseExpressionList(PlacementArgs, CommaLocs); } /// ParseCXXDeleteExpression - Parse a C++ delete-expression. Delete is used /// to free memory allocated by new. /// /// This method is called to parse the 'delete' expression after the optional /// '::' has been already parsed. If the '::' was present, "UseGlobal" is true /// and "Start" is its location. Otherwise, "Start" is the location of the /// 'delete' token. /// /// delete-expression: /// '::'[opt] 'delete' cast-expression /// '::'[opt] 'delete' '[' ']' cast-expression ExprResult Parser::ParseCXXDeleteExpression(bool UseGlobal, SourceLocation Start) { assert(Tok.is(tok::kw_delete) && "Expected 'delete' keyword"); ConsumeToken(); // Consume 'delete' // Array delete? bool ArrayDelete = false; if (Tok.is(tok::l_square) && NextToken().is(tok::r_square)) { // C++11 [expr.delete]p1: // Whenever the delete keyword is followed by empty square brackets, it // shall be interpreted as [array delete]. // [Footnote: A lambda expression with a lambda-introducer that consists // of empty square brackets can follow the delete keyword if // the lambda expression is enclosed in parentheses.] const Token Next = GetLookAheadToken(2); // Basic lookahead to check if we have a lambda expression. if (Next.isOneOf(tok::l_brace, tok::less) || (Next.is(tok::l_paren) && (GetLookAheadToken(3).is(tok::r_paren) || (GetLookAheadToken(3).is(tok::identifier) && GetLookAheadToken(4).is(tok::identifier))))) { TentativeParsingAction TPA(*this); SourceLocation LSquareLoc = Tok.getLocation(); SourceLocation RSquareLoc = NextToken().getLocation(); // SkipUntil can't skip pairs of ; don't emit a FixIt in this // case. SkipUntil({tok::l_brace, tok::less}, StopBeforeMatch); SourceLocation RBraceLoc; bool EmitFixIt = false; if (Tok.is(tok::l_brace)) { ConsumeBrace(); SkipUntil(tok::r_brace, StopBeforeMatch); RBraceLoc = Tok.getLocation(); EmitFixIt = true; } TPA.Revert(); if (EmitFixIt) Diag(Start, diag::err_lambda_after_delete) << SourceRange(Start, RSquareLoc) << FixItHint::CreateInsertion(LSquareLoc, "(") << FixItHint::CreateInsertion( Lexer::getLocForEndOfToken( RBraceLoc, 0, Actions.getSourceManager(), getLangOpts()), ")"); else Diag(Start, diag::err_lambda_after_delete) << SourceRange(Start, RSquareLoc); // Warn that the non-capturing lambda isn't surrounded by parentheses // to disambiguate it from 'delete[]'. ExprResult Lambda = ParseLambdaExpression(); if (Lambda.isInvalid()) return ExprError(); // Evaluate any postfix expressions used on the lambda. Lambda = ParsePostfixExpressionSuffix(Lambda); if (Lambda.isInvalid()) return ExprError(); return Actions.ActOnCXXDelete(Start, UseGlobal, /*ArrayForm=*/false, Lambda.get()); } ArrayDelete = true; BalancedDelimiterTracker T(*this, tok::l_square); T.consumeOpen(); T.consumeClose(); if (T.getCloseLocation().isInvalid()) return ExprError(); } ExprResult Operand(ParseCastExpression(AnyCastExpr)); if (Operand.isInvalid()) return Operand; return Actions.ActOnCXXDelete(Start, UseGlobal, ArrayDelete, Operand.get()); } /// ParseRequiresExpression - Parse a C++2a requires-expression. /// C++2a [expr.prim.req]p1 /// A requires-expression provides a concise way to express requirements on /// template arguments. A requirement is one that can be checked by name /// lookup (6.4) or by checking properties of types and expressions. /// /// requires-expression: /// 'requires' requirement-parameter-list[opt] requirement-body /// /// requirement-parameter-list: /// '(' parameter-declaration-clause[opt] ')' /// /// requirement-body: /// '{' requirement-seq '}' /// /// requirement-seq: /// requirement /// requirement-seq requirement /// /// requirement: /// simple-requirement /// type-requirement /// compound-requirement /// nested-requirement ExprResult Parser::ParseRequiresExpression() { assert(Tok.is(tok::kw_requires) && "Expected 'requires' keyword"); SourceLocation RequiresKWLoc = ConsumeToken(); // Consume 'requires' llvm::SmallVector LocalParameterDecls; if (Tok.is(tok::l_paren)) { // requirement parameter list is present. ParseScope LocalParametersScope(this, Scope::FunctionPrototypeScope | Scope::DeclScope); BalancedDelimiterTracker Parens(*this, tok::l_paren); Parens.consumeOpen(); if (!Tok.is(tok::r_paren)) { ParsedAttributes FirstArgAttrs(getAttrFactory()); SourceLocation EllipsisLoc; llvm::SmallVector LocalParameters; ParseParameterDeclarationClause(DeclaratorContext::RequiresExpr, FirstArgAttrs, LocalParameters, EllipsisLoc); if (EllipsisLoc.isValid()) Diag(EllipsisLoc, diag::err_requires_expr_parameter_list_ellipsis); for (auto &ParamInfo : LocalParameters) LocalParameterDecls.push_back(cast(ParamInfo.Param)); } Parens.consumeClose(); } BalancedDelimiterTracker Braces(*this, tok::l_brace); if (Braces.expectAndConsume()) return ExprError(); // Start of requirement list llvm::SmallVector Requirements; // C++2a [expr.prim.req]p2 // Expressions appearing within a requirement-body are unevaluated operands. EnterExpressionEvaluationContext Ctx( Actions, Sema::ExpressionEvaluationContext::Unevaluated); ParseScope BodyScope(this, Scope::DeclScope); RequiresExprBodyDecl *Body = Actions.ActOnStartRequiresExpr( RequiresKWLoc, LocalParameterDecls, getCurScope()); if (Tok.is(tok::r_brace)) { // Grammar does not allow an empty body. // requirement-body: // { requirement-seq } // requirement-seq: // requirement // requirement-seq requirement Diag(Tok, diag::err_empty_requires_expr); // Continue anyway and produce a requires expr with no requirements. } else { while (!Tok.is(tok::r_brace)) { switch (Tok.getKind()) { case tok::l_brace: { // Compound requirement // C++ [expr.prim.req.compound] // compound-requirement: // '{' expression '}' 'noexcept'[opt] // return-type-requirement[opt] ';' // return-type-requirement: // trailing-return-type // '->' cv-qualifier-seq[opt] constrained-parameter // cv-qualifier-seq[opt] abstract-declarator[opt] BalancedDelimiterTracker ExprBraces(*this, tok::l_brace); ExprBraces.consumeOpen(); ExprResult Expression = Actions.CorrectDelayedTyposInExpr(ParseExpression()); if (!Expression.isUsable()) { ExprBraces.skipToEnd(); SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } if (ExprBraces.consumeClose()) ExprBraces.skipToEnd(); concepts::Requirement *Req = nullptr; SourceLocation NoexceptLoc; TryConsumeToken(tok::kw_noexcept, NoexceptLoc); if (Tok.is(tok::semi)) { Req = Actions.ActOnCompoundRequirement(Expression.get(), NoexceptLoc); if (Req) Requirements.push_back(Req); break; } if (!TryConsumeToken(tok::arrow)) // User probably forgot the arrow, remind them and try to continue. Diag(Tok, diag::err_requires_expr_missing_arrow) << FixItHint::CreateInsertion(Tok.getLocation(), "->"); // Try to parse a 'type-constraint' if (TryAnnotateTypeConstraint()) { SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } if (!isTypeConstraintAnnotation()) { Diag(Tok, diag::err_requires_expr_expected_type_constraint); SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } CXXScopeSpec SS; if (Tok.is(tok::annot_cxxscope)) { Actions.RestoreNestedNameSpecifierAnnotation(Tok.getAnnotationValue(), Tok.getAnnotationRange(), SS); ConsumeAnnotationToken(); } Req = Actions.ActOnCompoundRequirement( Expression.get(), NoexceptLoc, SS, takeTemplateIdAnnotation(Tok), TemplateParameterDepth); ConsumeAnnotationToken(); if (Req) Requirements.push_back(Req); break; } default: { bool PossibleRequiresExprInSimpleRequirement = false; if (Tok.is(tok::kw_requires)) { auto IsNestedRequirement = [&] { RevertingTentativeParsingAction TPA(*this); ConsumeToken(); // 'requires' if (Tok.is(tok::l_brace)) // This is a requires expression // requires (T t) { // requires { t++; }; // ... ^ // } return false; if (Tok.is(tok::l_paren)) { // This might be the parameter list of a requires expression ConsumeParen(); auto Res = TryParseParameterDeclarationClause(); if (Res != TPResult::False) { // Skip to the closing parenthesis // FIXME: Don't traverse these tokens twice (here and in // TryParseParameterDeclarationClause). unsigned Depth = 1; while (Depth != 0) { if (Tok.is(tok::l_paren)) Depth++; else if (Tok.is(tok::r_paren)) Depth--; ConsumeAnyToken(); } // requires (T t) { // requires () ? // ... ^ // - OR - // requires (int x) ? // ... ^ // } if (Tok.is(tok::l_brace)) // requires (...) { // ^ - a requires expression as a // simple-requirement. return false; } } return true; }; if (IsNestedRequirement()) { ConsumeToken(); // Nested requirement // C++ [expr.prim.req.nested] // nested-requirement: // 'requires' constraint-expression ';' ExprResult ConstraintExpr = Actions.CorrectDelayedTyposInExpr(ParseConstraintExpression()); if (ConstraintExpr.isInvalid() || !ConstraintExpr.isUsable()) { SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } if (auto *Req = Actions.ActOnNestedRequirement(ConstraintExpr.get())) Requirements.push_back(Req); else { SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } break; } else PossibleRequiresExprInSimpleRequirement = true; } else if (Tok.is(tok::kw_typename)) { // This might be 'typename T::value_type;' (a type requirement) or // 'typename T::value_type{};' (a simple requirement). TentativeParsingAction TPA(*this); // We need to consume the typename to allow 'requires { typename a; }' SourceLocation TypenameKWLoc = ConsumeToken(); if (TryAnnotateCXXScopeToken()) { TPA.Commit(); SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } CXXScopeSpec SS; if (Tok.is(tok::annot_cxxscope)) { Actions.RestoreNestedNameSpecifierAnnotation( Tok.getAnnotationValue(), Tok.getAnnotationRange(), SS); ConsumeAnnotationToken(); } if (Tok.isOneOf(tok::identifier, tok::annot_template_id) && !NextToken().isOneOf(tok::l_brace, tok::l_paren)) { TPA.Commit(); SourceLocation NameLoc = Tok.getLocation(); IdentifierInfo *II = nullptr; TemplateIdAnnotation *TemplateId = nullptr; if (Tok.is(tok::identifier)) { II = Tok.getIdentifierInfo(); ConsumeToken(); } else { TemplateId = takeTemplateIdAnnotation(Tok); ConsumeAnnotationToken(); if (TemplateId->isInvalid()) break; } if (auto *Req = Actions.ActOnTypeRequirement(TypenameKWLoc, SS, NameLoc, II, TemplateId)) { Requirements.push_back(Req); } break; } TPA.Revert(); } // Simple requirement // C++ [expr.prim.req.simple] // simple-requirement: // expression ';' SourceLocation StartLoc = Tok.getLocation(); ExprResult Expression = Actions.CorrectDelayedTyposInExpr(ParseExpression()); if (!Expression.isUsable()) { SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } if (!Expression.isInvalid() && PossibleRequiresExprInSimpleRequirement) Diag(StartLoc, diag::warn_requires_expr_in_simple_requirement) << FixItHint::CreateInsertion(StartLoc, "requires"); if (auto *Req = Actions.ActOnSimpleRequirement(Expression.get())) Requirements.push_back(Req); else { SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } // User may have tried to put some compound requirement stuff here if (Tok.is(tok::kw_noexcept)) { Diag(Tok, diag::err_requires_expr_simple_requirement_noexcept) << FixItHint::CreateInsertion(StartLoc, "{") << FixItHint::CreateInsertion(Tok.getLocation(), "}"); SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); break; } break; } } if (ExpectAndConsumeSemi(diag::err_expected_semi_requirement)) { SkipUntil(tok::semi, tok::r_brace, SkipUntilFlags::StopBeforeMatch); TryConsumeToken(tok::semi); break; } } if (Requirements.empty()) { // Don't emit an empty requires expr here to avoid confusing the user with // other diagnostics quoting an empty requires expression they never // wrote. Braces.consumeClose(); Actions.ActOnFinishRequiresExpr(); return ExprError(); } } Braces.consumeClose(); Actions.ActOnFinishRequiresExpr(); return Actions.ActOnRequiresExpr(RequiresKWLoc, Body, LocalParameterDecls, Requirements, Braces.getCloseLocation()); } static TypeTrait TypeTraitFromTokKind(tok::TokenKind kind) { switch (kind) { default: llvm_unreachable("Not a known type trait"); #define TYPE_TRAIT_1(Spelling, Name, Key) \ case tok::kw_ ## Spelling: return UTT_ ## Name; #define TYPE_TRAIT_2(Spelling, Name, Key) \ case tok::kw_ ## Spelling: return BTT_ ## Name; #include "clang/Basic/TokenKinds.def" #define TYPE_TRAIT_N(Spelling, Name, Key) \ case tok::kw_ ## Spelling: return TT_ ## Name; #include "clang/Basic/TokenKinds.def" } } static ArrayTypeTrait ArrayTypeTraitFromTokKind(tok::TokenKind kind) { switch (kind) { default: llvm_unreachable("Not a known array type trait"); #define ARRAY_TYPE_TRAIT(Spelling, Name, Key) \ case tok::kw_##Spelling: \ return ATT_##Name; #include "clang/Basic/TokenKinds.def" } } static ExpressionTrait ExpressionTraitFromTokKind(tok::TokenKind kind) { switch (kind) { default: llvm_unreachable("Not a known unary expression trait."); #define EXPRESSION_TRAIT(Spelling, Name, Key) \ case tok::kw_##Spelling: \ return ET_##Name; #include "clang/Basic/TokenKinds.def" } } static unsigned TypeTraitArity(tok::TokenKind kind) { switch (kind) { default: llvm_unreachable("Not a known type trait"); #define TYPE_TRAIT(N,Spelling,K) case tok::kw_##Spelling: return N; #include "clang/Basic/TokenKinds.def" } } /// Parse the built-in type-trait pseudo-functions that allow /// implementation of the TR1/C++11 type traits templates. /// /// primary-expression: /// unary-type-trait '(' type-id ')' /// binary-type-trait '(' type-id ',' type-id ')' /// type-trait '(' type-id-seq ')' /// /// type-id-seq: /// type-id ...[opt] type-id-seq[opt] /// ExprResult Parser::ParseTypeTrait() { tok::TokenKind Kind = Tok.getKind(); unsigned Arity = TypeTraitArity(Kind); SourceLocation Loc = ConsumeToken(); BalancedDelimiterTracker Parens(*this, tok::l_paren); if (Parens.expectAndConsume()) return ExprError(); SmallVector Args; do { // Parse the next type. TypeResult Ty = ParseTypeName(); if (Ty.isInvalid()) { Parens.skipToEnd(); return ExprError(); } // Parse the ellipsis, if present. if (Tok.is(tok::ellipsis)) { Ty = Actions.ActOnPackExpansion(Ty.get(), ConsumeToken()); if (Ty.isInvalid()) { Parens.skipToEnd(); return ExprError(); } } // Add this type to the list of arguments. Args.push_back(Ty.get()); } while (TryConsumeToken(tok::comma)); if (Parens.consumeClose()) return ExprError(); SourceLocation EndLoc = Parens.getCloseLocation(); if (Arity && Args.size() != Arity) { Diag(EndLoc, diag::err_type_trait_arity) << Arity << 0 << (Arity > 1) << (int)Args.size() << SourceRange(Loc); return ExprError(); } if (!Arity && Args.empty()) { Diag(EndLoc, diag::err_type_trait_arity) << 1 << 1 << 1 << (int)Args.size() << SourceRange(Loc); return ExprError(); } return Actions.ActOnTypeTrait(TypeTraitFromTokKind(Kind), Loc, Args, EndLoc); } /// ParseArrayTypeTrait - Parse the built-in array type-trait /// pseudo-functions. /// /// primary-expression: /// [Embarcadero] '__array_rank' '(' type-id ')' /// [Embarcadero] '__array_extent' '(' type-id ',' expression ')' /// ExprResult Parser::ParseArrayTypeTrait() { ArrayTypeTrait ATT = ArrayTypeTraitFromTokKind(Tok.getKind()); SourceLocation Loc = ConsumeToken(); BalancedDelimiterTracker T(*this, tok::l_paren); if (T.expectAndConsume()) return ExprError(); TypeResult Ty = ParseTypeName(); if (Ty.isInvalid()) { SkipUntil(tok::comma, StopAtSemi); SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } switch (ATT) { case ATT_ArrayRank: { T.consumeClose(); return Actions.ActOnArrayTypeTrait(ATT, Loc, Ty.get(), nullptr, T.getCloseLocation()); } case ATT_ArrayExtent: { if (ExpectAndConsume(tok::comma)) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } ExprResult DimExpr = ParseExpression(); T.consumeClose(); return Actions.ActOnArrayTypeTrait(ATT, Loc, Ty.get(), DimExpr.get(), T.getCloseLocation()); } } llvm_unreachable("Invalid ArrayTypeTrait!"); } /// ParseExpressionTrait - Parse built-in expression-trait /// pseudo-functions like __is_lvalue_expr( xxx ). /// /// primary-expression: /// [Embarcadero] expression-trait '(' expression ')' /// ExprResult Parser::ParseExpressionTrait() { ExpressionTrait ET = ExpressionTraitFromTokKind(Tok.getKind()); SourceLocation Loc = ConsumeToken(); BalancedDelimiterTracker T(*this, tok::l_paren); if (T.expectAndConsume()) return ExprError(); ExprResult Expr = ParseExpression(); T.consumeClose(); return Actions.ActOnExpressionTrait(ET, Loc, Expr.get(), T.getCloseLocation()); } /// ParseCXXAmbiguousParenExpression - We have parsed the left paren of a /// parenthesized ambiguous type-id. This uses tentative parsing to disambiguate /// based on the context past the parens. ExprResult Parser::ParseCXXAmbiguousParenExpression(ParenParseOption &ExprType, ParsedType &CastTy, BalancedDelimiterTracker &Tracker, ColonProtectionRAIIObject &ColonProt) { assert(getLangOpts().CPlusPlus && "Should only be called for C++!"); assert(ExprType == CastExpr && "Compound literals are not ambiguous!"); assert(isTypeIdInParens() && "Not a type-id!"); ExprResult Result(true); CastTy = nullptr; // We need to disambiguate a very ugly part of the C++ syntax: // // (T())x; - type-id // (T())*x; - type-id // (T())/x; - expression // (T()); - expression // // The bad news is that we cannot use the specialized tentative parser, since // it can only verify that the thing inside the parens can be parsed as // type-id, it is not useful for determining the context past the parens. // // The good news is that the parser can disambiguate this part without // making any unnecessary Action calls. // // It uses a scheme similar to parsing inline methods. The parenthesized // tokens are cached, the context that follows is determined (possibly by // parsing a cast-expression), and then we re-introduce the cached tokens // into the token stream and parse them appropriately. ParenParseOption ParseAs; CachedTokens Toks; // Store the tokens of the parentheses. We will parse them after we determine // the context that follows them. if (!ConsumeAndStoreUntil(tok::r_paren, Toks)) { // We didn't find the ')' we expected. Tracker.consumeClose(); return ExprError(); } if (Tok.is(tok::l_brace)) { ParseAs = CompoundLiteral; } else { bool NotCastExpr; if (Tok.is(tok::l_paren) && NextToken().is(tok::r_paren)) { NotCastExpr = true; } else { // Try parsing the cast-expression that may follow. // If it is not a cast-expression, NotCastExpr will be true and no token // will be consumed. ColonProt.restore(); Result = ParseCastExpression(AnyCastExpr, false/*isAddressofOperand*/, NotCastExpr, // type-id has priority. IsTypeCast); } // If we parsed a cast-expression, it's really a type-id, otherwise it's // an expression. ParseAs = NotCastExpr ? SimpleExpr : CastExpr; } // Create a fake EOF to mark end of Toks buffer. Token AttrEnd; AttrEnd.startToken(); AttrEnd.setKind(tok::eof); AttrEnd.setLocation(Tok.getLocation()); AttrEnd.setEofData(Toks.data()); Toks.push_back(AttrEnd); // The current token should go after the cached tokens. Toks.push_back(Tok); // Re-enter the stored parenthesized tokens into the token stream, so we may // parse them now. PP.EnterTokenStream(Toks, /*DisableMacroExpansion*/ true, /*IsReinject*/ true); // Drop the current token and bring the first cached one. It's the same token // as when we entered this function. ConsumeAnyToken(); if (ParseAs >= CompoundLiteral) { // Parse the type declarator. DeclSpec DS(AttrFactory); Declarator DeclaratorInfo(DS, DeclaratorContext::TypeName); { ColonProtectionRAIIObject InnerColonProtection(*this); ParseSpecifierQualifierList(DS); ParseDeclarator(DeclaratorInfo); } // Match the ')'. Tracker.consumeClose(); ColonProt.restore(); // Consume EOF marker for Toks buffer. assert(Tok.is(tok::eof) && Tok.getEofData() == AttrEnd.getEofData()); ConsumeAnyToken(); if (ParseAs == CompoundLiteral) { ExprType = CompoundLiteral; if (DeclaratorInfo.isInvalidType()) return ExprError(); TypeResult Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); return ParseCompoundLiteralExpression(Ty.get(), Tracker.getOpenLocation(), Tracker.getCloseLocation()); } // We parsed '(' type-id ')' and the thing after it wasn't a '{'. assert(ParseAs == CastExpr); if (DeclaratorInfo.isInvalidType()) return ExprError(); // Result is what ParseCastExpression returned earlier. if (!Result.isInvalid()) Result = Actions.ActOnCastExpr(getCurScope(), Tracker.getOpenLocation(), DeclaratorInfo, CastTy, Tracker.getCloseLocation(), Result.get()); return Result; } // Not a compound literal, and not followed by a cast-expression. assert(ParseAs == SimpleExpr); ExprType = SimpleExpr; Result = ParseExpression(); if (!Result.isInvalid() && Tok.is(tok::r_paren)) Result = Actions.ActOnParenExpr(Tracker.getOpenLocation(), Tok.getLocation(), Result.get()); // Match the ')'. if (Result.isInvalid()) { while (Tok.isNot(tok::eof)) ConsumeAnyToken(); assert(Tok.getEofData() == AttrEnd.getEofData()); ConsumeAnyToken(); return ExprError(); } Tracker.consumeClose(); // Consume EOF marker for Toks buffer. assert(Tok.is(tok::eof) && Tok.getEofData() == AttrEnd.getEofData()); ConsumeAnyToken(); return Result; } /// Parse a __builtin_bit_cast(T, E). ExprResult Parser::ParseBuiltinBitCast() { SourceLocation KWLoc = ConsumeToken(); BalancedDelimiterTracker T(*this, tok::l_paren); if (T.expectAndConsume(diag::err_expected_lparen_after, "__builtin_bit_cast")) return ExprError(); // Parse the common declaration-specifiers piece. DeclSpec DS(AttrFactory); ParseSpecifierQualifierList(DS); // Parse the abstract-declarator, if present. Declarator DeclaratorInfo(DS, DeclaratorContext::TypeName); ParseDeclarator(DeclaratorInfo); if (ExpectAndConsume(tok::comma)) { Diag(Tok.getLocation(), diag::err_expected) << tok::comma; SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } ExprResult Operand = ParseExpression(); if (T.consumeClose()) return ExprError(); if (Operand.isInvalid() || DeclaratorInfo.isInvalidType()) return ExprError(); return Actions.ActOnBuiltinBitCastExpr(KWLoc, DeclaratorInfo, Operand, T.getCloseLocation()); }