//===--- ParseExpr.cpp - Expression Parsing -------------------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// /// /// \file /// Provides the Expression parsing implementation. /// /// Expressions in C99 basically consist of a bunch of binary operators with /// unary operators and other random stuff at the leaves. /// /// In the C99 grammar, these unary operators bind tightest and are represented /// as the 'cast-expression' production. Everything else is either a binary /// operator (e.g. '/') or a ternary operator ("?:"). The unary leaves are /// handled by ParseCastExpression, the higher level pieces are handled by /// ParseBinaryExpression. /// //===----------------------------------------------------------------------===// #include "clang/Parse/Parser.h" #include "clang/AST/ASTContext.h" #include "clang/Basic/PrettyStackTrace.h" #include "clang/Parse/RAIIObjectsForParser.h" #include "clang/Sema/DeclSpec.h" #include "clang/Sema/ParsedTemplate.h" #include "clang/Sema/Scope.h" #include "clang/Sema/TypoCorrection.h" #include "llvm/ADT/SmallVector.h" using namespace clang; /// Simple precedence-based parser for binary/ternary operators. /// /// Note: we diverge from the C99 grammar when parsing the assignment-expression /// production. C99 specifies that the LHS of an assignment operator should be /// parsed as a unary-expression, but consistency dictates that it be a /// conditional-expession. In practice, the important thing here is that the /// LHS of an assignment has to be an l-value, which productions between /// unary-expression and conditional-expression don't produce. Because we want /// consistency, we parse the LHS as a conditional-expression, then check for /// l-value-ness in semantic analysis stages. /// /// \verbatim /// pm-expression: [C++ 5.5] /// cast-expression /// pm-expression '.*' cast-expression /// pm-expression '->*' cast-expression /// /// multiplicative-expression: [C99 6.5.5] /// Note: in C++, apply pm-expression instead of cast-expression /// cast-expression /// multiplicative-expression '*' cast-expression /// multiplicative-expression '/' cast-expression /// multiplicative-expression '%' cast-expression /// /// additive-expression: [C99 6.5.6] /// multiplicative-expression /// additive-expression '+' multiplicative-expression /// additive-expression '-' multiplicative-expression /// /// shift-expression: [C99 6.5.7] /// additive-expression /// shift-expression '<<' additive-expression /// shift-expression '>>' additive-expression /// /// compare-expression: [C++20 expr.spaceship] /// shift-expression /// compare-expression '<=>' shift-expression /// /// relational-expression: [C99 6.5.8] /// compare-expression /// relational-expression '<' compare-expression /// relational-expression '>' compare-expression /// relational-expression '<=' compare-expression /// relational-expression '>=' compare-expression /// /// equality-expression: [C99 6.5.9] /// relational-expression /// equality-expression '==' relational-expression /// equality-expression '!=' relational-expression /// /// AND-expression: [C99 6.5.10] /// equality-expression /// AND-expression '&' equality-expression /// /// exclusive-OR-expression: [C99 6.5.11] /// AND-expression /// exclusive-OR-expression '^' AND-expression /// /// inclusive-OR-expression: [C99 6.5.12] /// exclusive-OR-expression /// inclusive-OR-expression '|' exclusive-OR-expression /// /// logical-AND-expression: [C99 6.5.13] /// inclusive-OR-expression /// logical-AND-expression '&&' inclusive-OR-expression /// /// logical-OR-expression: [C99 6.5.14] /// logical-AND-expression /// logical-OR-expression '||' logical-AND-expression /// /// conditional-expression: [C99 6.5.15] /// logical-OR-expression /// logical-OR-expression '?' expression ':' conditional-expression /// [GNU] logical-OR-expression '?' ':' conditional-expression /// [C++] the third operand is an assignment-expression /// /// assignment-expression: [C99 6.5.16] /// conditional-expression /// unary-expression assignment-operator assignment-expression /// [C++] throw-expression [C++ 15] /// /// assignment-operator: one of /// = *= /= %= += -= <<= >>= &= ^= |= /// /// expression: [C99 6.5.17] /// assignment-expression ...[opt] /// expression ',' assignment-expression ...[opt] /// \endverbatim ExprResult Parser::ParseExpression(TypeCastState isTypeCast) { ExprResult LHS(ParseAssignmentExpression(isTypeCast)); return ParseRHSOfBinaryExpression(LHS, prec::Comma); } /// This routine is called when the '@' is seen and consumed. /// Current token is an Identifier and is not a 'try'. This /// routine is necessary to disambiguate \@try-statement from, /// for example, \@encode-expression. /// ExprResult Parser::ParseExpressionWithLeadingAt(SourceLocation AtLoc) { ExprResult LHS(ParseObjCAtExpression(AtLoc)); return ParseRHSOfBinaryExpression(LHS, prec::Comma); } /// This routine is called when a leading '__extension__' is seen and /// consumed. This is necessary because the token gets consumed in the /// process of disambiguating between an expression and a declaration. ExprResult Parser::ParseExpressionWithLeadingExtension(SourceLocation ExtLoc) { ExprResult LHS(true); { // Silence extension warnings in the sub-expression ExtensionRAIIObject O(Diags); LHS = ParseCastExpression(false); } if (!LHS.isInvalid()) LHS = Actions.ActOnUnaryOp(getCurScope(), ExtLoc, tok::kw___extension__, LHS.get()); return ParseRHSOfBinaryExpression(LHS, prec::Comma); } /// Parse an expr that doesn't include (top-level) commas. ExprResult Parser::ParseAssignmentExpression(TypeCastState isTypeCast) { if (Tok.is(tok::code_completion)) { Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); cutOffParsing(); return ExprError(); } if (Tok.is(tok::kw_throw)) return ParseThrowExpression(); if (Tok.is(tok::kw_co_yield)) return ParseCoyieldExpression(); ExprResult LHS = ParseCastExpression(/*isUnaryExpression=*/false, /*isAddressOfOperand=*/false, isTypeCast); return ParseRHSOfBinaryExpression(LHS, prec::Assignment); } /// Parse an assignment expression where part of an Objective-C message /// send has already been parsed. /// /// In this case \p LBracLoc indicates the location of the '[' of the message /// send, and either \p ReceiverName or \p ReceiverExpr is non-null indicating /// the receiver of the message. /// /// Since this handles full assignment-expression's, it handles postfix /// expressions and other binary operators for these expressions as well. ExprResult Parser::ParseAssignmentExprWithObjCMessageExprStart(SourceLocation LBracLoc, SourceLocation SuperLoc, ParsedType ReceiverType, Expr *ReceiverExpr) { ExprResult R = ParseObjCMessageExpressionBody(LBracLoc, SuperLoc, ReceiverType, ReceiverExpr); R = ParsePostfixExpressionSuffix(R); return ParseRHSOfBinaryExpression(R, prec::Assignment); } ExprResult Parser::ParseConstantExpressionInExprEvalContext(TypeCastState isTypeCast) { assert(Actions.ExprEvalContexts.back().Context == Sema::ExpressionEvaluationContext::ConstantEvaluated && "Call this function only if your ExpressionEvaluationContext is " "already ConstantEvaluated"); ExprResult LHS(ParseCastExpression(false, false, isTypeCast)); ExprResult Res(ParseRHSOfBinaryExpression(LHS, prec::Conditional)); return Actions.ActOnConstantExpression(Res); } ExprResult Parser::ParseConstantExpression(TypeCastState isTypeCast) { // C++03 [basic.def.odr]p2: // An expression is potentially evaluated unless it appears where an // integral constant expression is required (see 5.19) [...]. // C++98 and C++11 have no such rule, but this is only a defect in C++98. EnterExpressionEvaluationContext ConstantEvaluated( Actions, Sema::ExpressionEvaluationContext::ConstantEvaluated); return ParseConstantExpressionInExprEvalContext(isTypeCast); } /// Parse a constraint-expression. /// /// \verbatim /// constraint-expression: [Concepts TS temp.constr.decl p1] /// logical-or-expression /// \endverbatim ExprResult Parser::ParseConstraintExpression() { // FIXME: this may erroneously consume a function-body as the braced // initializer list of a compound literal // // FIXME: this may erroneously consume a parenthesized rvalue reference // declarator as a parenthesized address-of-label expression ExprResult LHS(ParseCastExpression(/*isUnaryExpression=*/false)); ExprResult Res(ParseRHSOfBinaryExpression(LHS, prec::LogicalOr)); return Res; } bool Parser::isNotExpressionStart() { tok::TokenKind K = Tok.getKind(); if (K == tok::l_brace || K == tok::r_brace || K == tok::kw_for || K == tok::kw_while || K == tok::kw_if || K == tok::kw_else || K == tok::kw_goto || K == tok::kw_try) return true; // If this is a decl-specifier, we can't be at the start of an expression. return isKnownToBeDeclarationSpecifier(); } bool Parser::isFoldOperator(prec::Level Level) const { return Level > prec::Unknown && Level != prec::Conditional && Level != prec::Spaceship; } bool Parser::isFoldOperator(tok::TokenKind Kind) const { return isFoldOperator(getBinOpPrecedence(Kind, GreaterThanIsOperator, true)); } /// Parse a binary expression that starts with \p LHS and has a /// precedence of at least \p MinPrec. ExprResult Parser::ParseRHSOfBinaryExpression(ExprResult LHS, prec::Level MinPrec) { prec::Level NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator, getLangOpts().CPlusPlus11); SourceLocation ColonLoc; while (1) { // If this token has a lower precedence than we are allowed to parse (e.g. // because we are called recursively, or because the token is not a binop), // then we are done! if (NextTokPrec < MinPrec) return LHS; // Consume the operator, saving the operator token for error reporting. Token OpToken = Tok; ConsumeToken(); if (OpToken.is(tok::caretcaret)) { return ExprError(Diag(Tok, diag::err_opencl_logical_exclusive_or)); } // If we're potentially in a template-id, we may now be able to determine // whether we're actually in one or not. if (OpToken.isOneOf(tok::comma, tok::greater, tok::greatergreater, tok::greatergreatergreater) && checkPotentialAngleBracketDelimiter(OpToken)) return ExprError(); // Bail out when encountering a comma followed by a token which can't // possibly be the start of an expression. For instance: // int f() { return 1, } // We can't do this before consuming the comma, because // isNotExpressionStart() looks at the token stream. if (OpToken.is(tok::comma) && isNotExpressionStart()) { PP.EnterToken(Tok); Tok = OpToken; return LHS; } // If the next token is an ellipsis, then this is a fold-expression. Leave // it alone so we can handle it in the paren expression. if (isFoldOperator(NextTokPrec) && Tok.is(tok::ellipsis)) { // FIXME: We can't check this via lookahead before we consume the token // because that tickles a lexer bug. PP.EnterToken(Tok); Tok = OpToken; return LHS; } // Special case handling for the ternary operator. ExprResult TernaryMiddle(true); if (NextTokPrec == prec::Conditional) { if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) { // Parse a braced-init-list here for error recovery purposes. SourceLocation BraceLoc = Tok.getLocation(); TernaryMiddle = ParseBraceInitializer(); if (!TernaryMiddle.isInvalid()) { Diag(BraceLoc, diag::err_init_list_bin_op) << /*RHS*/ 1 << PP.getSpelling(OpToken) << Actions.getExprRange(TernaryMiddle.get()); TernaryMiddle = ExprError(); } } else if (Tok.isNot(tok::colon)) { // Don't parse FOO:BAR as if it were a typo for FOO::BAR. ColonProtectionRAIIObject X(*this); // Handle this production specially: // logical-OR-expression '?' expression ':' conditional-expression // In particular, the RHS of the '?' is 'expression', not // 'logical-OR-expression' as we might expect. TernaryMiddle = ParseExpression(); } else { // Special case handling of "X ? Y : Z" where Y is empty: // logical-OR-expression '?' ':' conditional-expression [GNU] TernaryMiddle = nullptr; Diag(Tok, diag::ext_gnu_conditional_expr); } if (TernaryMiddle.isInvalid()) { Actions.CorrectDelayedTyposInExpr(LHS); LHS = ExprError(); TernaryMiddle = nullptr; } if (!TryConsumeToken(tok::colon, ColonLoc)) { // Otherwise, we're missing a ':'. Assume that this was a typo that // the user forgot. If we're not in a macro expansion, we can suggest // a fixit hint. If there were two spaces before the current token, // suggest inserting the colon in between them, otherwise insert ": ". SourceLocation FILoc = Tok.getLocation(); const char *FIText = ": "; const SourceManager &SM = PP.getSourceManager(); if (FILoc.isFileID() || PP.isAtStartOfMacroExpansion(FILoc, &FILoc)) { assert(FILoc.isFileID()); bool IsInvalid = false; const char *SourcePtr = SM.getCharacterData(FILoc.getLocWithOffset(-1), &IsInvalid); if (!IsInvalid && *SourcePtr == ' ') { SourcePtr = SM.getCharacterData(FILoc.getLocWithOffset(-2), &IsInvalid); if (!IsInvalid && *SourcePtr == ' ') { FILoc = FILoc.getLocWithOffset(-1); FIText = ":"; } } } Diag(Tok, diag::err_expected) << tok::colon << FixItHint::CreateInsertion(FILoc, FIText); Diag(OpToken, diag::note_matching) << tok::question; ColonLoc = Tok.getLocation(); } } // Code completion for the right-hand side of an assignment expression // goes through a special hook that takes the left-hand side into account. if (Tok.is(tok::code_completion) && NextTokPrec == prec::Assignment) { Actions.CodeCompleteAssignmentRHS(getCurScope(), LHS.get()); cutOffParsing(); return ExprError(); } // Parse another leaf here for the RHS of the operator. // ParseCastExpression works here because all RHS expressions in C have it // as a prefix, at least. However, in C++, an assignment-expression could // be a throw-expression, which is not a valid cast-expression. // Therefore we need some special-casing here. // Also note that the third operand of the conditional operator is // an assignment-expression in C++, and in C++11, we can have a // braced-init-list on the RHS of an assignment. For better diagnostics, // parse as if we were allowed braced-init-lists everywhere, and check that // they only appear on the RHS of assignments later. ExprResult RHS; bool RHSIsInitList = false; if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) { RHS = ParseBraceInitializer(); RHSIsInitList = true; } else if (getLangOpts().CPlusPlus && NextTokPrec <= prec::Conditional) RHS = ParseAssignmentExpression(); else RHS = ParseCastExpression(false); if (RHS.isInvalid()) { // FIXME: Errors generated by the delayed typo correction should be // printed before errors from parsing the RHS, not after. Actions.CorrectDelayedTyposInExpr(LHS); if (TernaryMiddle.isUsable()) TernaryMiddle = Actions.CorrectDelayedTyposInExpr(TernaryMiddle); LHS = ExprError(); } // Remember the precedence of this operator and get the precedence of the // operator immediately to the right of the RHS. prec::Level ThisPrec = NextTokPrec; NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator, getLangOpts().CPlusPlus11); // Assignment and conditional expressions are right-associative. bool isRightAssoc = ThisPrec == prec::Conditional || ThisPrec == prec::Assignment; // Get the precedence of the operator to the right of the RHS. If it binds // more tightly with RHS than we do, evaluate it completely first. if (ThisPrec < NextTokPrec || (ThisPrec == NextTokPrec && isRightAssoc)) { if (!RHS.isInvalid() && RHSIsInitList) { Diag(Tok, diag::err_init_list_bin_op) << /*LHS*/0 << PP.getSpelling(Tok) << Actions.getExprRange(RHS.get()); RHS = ExprError(); } // If this is left-associative, only parse things on the RHS that bind // more tightly than the current operator. If it is left-associative, it // is okay, to bind exactly as tightly. For example, compile A=B=C=D as // A=(B=(C=D)), where each paren is a level of recursion here. // The function takes ownership of the RHS. RHS = ParseRHSOfBinaryExpression(RHS, static_cast(ThisPrec + !isRightAssoc)); RHSIsInitList = false; if (RHS.isInvalid()) { // FIXME: Errors generated by the delayed typo correction should be // printed before errors from ParseRHSOfBinaryExpression, not after. Actions.CorrectDelayedTyposInExpr(LHS); if (TernaryMiddle.isUsable()) TernaryMiddle = Actions.CorrectDelayedTyposInExpr(TernaryMiddle); LHS = ExprError(); } NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator, getLangOpts().CPlusPlus11); } if (!RHS.isInvalid() && RHSIsInitList) { if (ThisPrec == prec::Assignment) { Diag(OpToken, diag::warn_cxx98_compat_generalized_initializer_lists) << Actions.getExprRange(RHS.get()); } else if (ColonLoc.isValid()) { Diag(ColonLoc, diag::err_init_list_bin_op) << /*RHS*/1 << ":" << Actions.getExprRange(RHS.get()); LHS = ExprError(); } else { Diag(OpToken, diag::err_init_list_bin_op) << /*RHS*/1 << PP.getSpelling(OpToken) << Actions.getExprRange(RHS.get()); LHS = ExprError(); } } ExprResult OrigLHS = LHS; if (!LHS.isInvalid()) { // Combine the LHS and RHS into the LHS (e.g. build AST). if (TernaryMiddle.isInvalid()) { // If we're using '>>' as an operator within a template // argument list (in C++98), suggest the addition of // parentheses so that the code remains well-formed in C++0x. if (!GreaterThanIsOperator && OpToken.is(tok::greatergreater)) SuggestParentheses(OpToken.getLocation(), diag::warn_cxx11_right_shift_in_template_arg, SourceRange(Actions.getExprRange(LHS.get()).getBegin(), Actions.getExprRange(RHS.get()).getEnd())); LHS = Actions.ActOnBinOp(getCurScope(), OpToken.getLocation(), OpToken.getKind(), LHS.get(), RHS.get()); } else { LHS = Actions.ActOnConditionalOp(OpToken.getLocation(), ColonLoc, LHS.get(), TernaryMiddle.get(), RHS.get()); } // In this case, ActOnBinOp or ActOnConditionalOp performed the // CorrectDelayedTyposInExpr check. if (!getLangOpts().CPlusPlus) continue; } // Ensure potential typos aren't left undiagnosed. if (LHS.isInvalid()) { Actions.CorrectDelayedTyposInExpr(OrigLHS); Actions.CorrectDelayedTyposInExpr(TernaryMiddle); Actions.CorrectDelayedTyposInExpr(RHS); } } } /// Parse a cast-expression, or, if \p isUnaryExpression is true, /// parse a unary-expression. /// /// \p isAddressOfOperand exists because an id-expression that is the /// operand of address-of gets special treatment due to member pointers. /// ExprResult Parser::ParseCastExpression(bool isUnaryExpression, bool isAddressOfOperand, TypeCastState isTypeCast, bool isVectorLiteral) { bool NotCastExpr; ExprResult Res = ParseCastExpression(isUnaryExpression, isAddressOfOperand, NotCastExpr, isTypeCast, isVectorLiteral); if (NotCastExpr) Diag(Tok, diag::err_expected_expression); return Res; } namespace { class CastExpressionIdValidator : public CorrectionCandidateCallback { public: CastExpressionIdValidator(Token Next, bool AllowTypes, bool AllowNonTypes) : NextToken(Next), AllowNonTypes(AllowNonTypes) { WantTypeSpecifiers = WantFunctionLikeCasts = AllowTypes; } bool ValidateCandidate(const TypoCorrection &candidate) override { NamedDecl *ND = candidate.getCorrectionDecl(); if (!ND) return candidate.isKeyword(); if (isa(ND)) return WantTypeSpecifiers; if (!AllowNonTypes || !CorrectionCandidateCallback::ValidateCandidate(candidate)) return false; if (!NextToken.isOneOf(tok::equal, tok::arrow, tok::period)) return true; for (auto *C : candidate) { NamedDecl *ND = C->getUnderlyingDecl(); if (isa(ND) && !isa(ND)) return true; } return false; } private: Token NextToken; bool AllowNonTypes; }; } /// Parse a cast-expression, or, if \pisUnaryExpression is true, parse /// a unary-expression. /// /// \p isAddressOfOperand exists because an id-expression that is the operand /// of address-of gets special treatment due to member pointers. NotCastExpr /// is set to true if the token is not the start of a cast-expression, and no /// diagnostic is emitted in this case and no tokens are consumed. /// /// \verbatim /// cast-expression: [C99 6.5.4] /// unary-expression /// '(' type-name ')' cast-expression /// /// unary-expression: [C99 6.5.3] /// postfix-expression /// '++' unary-expression /// '--' unary-expression /// [Coro] 'co_await' cast-expression /// unary-operator cast-expression /// 'sizeof' unary-expression /// 'sizeof' '(' type-name ')' /// [C++11] 'sizeof' '...' '(' identifier ')' /// [GNU] '__alignof' unary-expression /// [GNU] '__alignof' '(' type-name ')' /// [C11] '_Alignof' '(' type-name ')' /// [C++11] 'alignof' '(' type-id ')' /// [GNU] '&&' identifier /// [C++11] 'noexcept' '(' expression ')' [C++11 5.3.7] /// [C++] new-expression /// [C++] delete-expression /// /// unary-operator: one of /// '&' '*' '+' '-' '~' '!' /// [GNU] '__extension__' '__real' '__imag' /// /// primary-expression: [C99 6.5.1] /// [C99] identifier /// [C++] id-expression /// constant /// string-literal /// [C++] boolean-literal [C++ 2.13.5] /// [C++11] 'nullptr' [C++11 2.14.7] /// [C++11] user-defined-literal /// '(' expression ')' /// [C11] generic-selection /// '__func__' [C99 6.4.2.2] /// [GNU] '__FUNCTION__' /// [MS] '__FUNCDNAME__' /// [MS] 'L__FUNCTION__' /// [GNU] '__PRETTY_FUNCTION__' /// [GNU] '(' compound-statement ')' /// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' /// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' /// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' /// assign-expr ')' /// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' /// [GNU] '__null' /// [OBJC] '[' objc-message-expr ']' /// [OBJC] '\@selector' '(' objc-selector-arg ')' /// [OBJC] '\@protocol' '(' identifier ')' /// [OBJC] '\@encode' '(' type-name ')' /// [OBJC] objc-string-literal /// [C++] simple-type-specifier '(' expression-list[opt] ')' [C++ 5.2.3] /// [C++11] simple-type-specifier braced-init-list [C++11 5.2.3] /// [C++] typename-specifier '(' expression-list[opt] ')' [C++ 5.2.3] /// [C++11] typename-specifier braced-init-list [C++11 5.2.3] /// [C++] 'const_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] /// [C++] 'dynamic_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] /// [C++] 'reinterpret_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] /// [C++] 'static_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] /// [C++] 'typeid' '(' expression ')' [C++ 5.2p1] /// [C++] 'typeid' '(' type-id ')' [C++ 5.2p1] /// [C++] 'this' [C++ 9.3.2] /// [G++] unary-type-trait '(' type-id ')' /// [G++] binary-type-trait '(' type-id ',' type-id ')' [TODO] /// [EMBT] array-type-trait '(' type-id ',' integer ')' /// [clang] '^' block-literal /// /// constant: [C99 6.4.4] /// integer-constant /// floating-constant /// enumeration-constant -> identifier /// character-constant /// /// id-expression: [C++ 5.1] /// unqualified-id /// qualified-id /// /// unqualified-id: [C++ 5.1] /// identifier /// operator-function-id /// conversion-function-id /// '~' class-name /// template-id /// /// new-expression: [C++ 5.3.4] /// '::'[opt] 'new' new-placement[opt] new-type-id /// new-initializer[opt] /// '::'[opt] 'new' new-placement[opt] '(' type-id ')' /// new-initializer[opt] /// /// delete-expression: [C++ 5.3.5] /// '::'[opt] 'delete' cast-expression /// '::'[opt] 'delete' '[' ']' cast-expression /// /// [GNU/Embarcadero] unary-type-trait: /// '__is_arithmetic' /// '__is_floating_point' /// '__is_integral' /// '__is_lvalue_expr' /// '__is_rvalue_expr' /// '__is_complete_type' /// '__is_void' /// '__is_array' /// '__is_function' /// '__is_reference' /// '__is_lvalue_reference' /// '__is_rvalue_reference' /// '__is_fundamental' /// '__is_object' /// '__is_scalar' /// '__is_compound' /// '__is_pointer' /// '__is_member_object_pointer' /// '__is_member_function_pointer' /// '__is_member_pointer' /// '__is_const' /// '__is_volatile' /// '__is_trivial' /// '__is_standard_layout' /// '__is_signed' /// '__is_unsigned' /// /// [GNU] unary-type-trait: /// '__has_nothrow_assign' /// '__has_nothrow_copy' /// '__has_nothrow_constructor' /// '__has_trivial_assign' [TODO] /// '__has_trivial_copy' [TODO] /// '__has_trivial_constructor' /// '__has_trivial_destructor' /// '__has_virtual_destructor' /// '__is_abstract' [TODO] /// '__is_class' /// '__is_empty' [TODO] /// '__is_enum' /// '__is_final' /// '__is_pod' /// '__is_polymorphic' /// '__is_sealed' [MS] /// '__is_trivial' /// '__is_union' /// '__has_unique_object_representations' /// /// [Clang] unary-type-trait: /// '__is_aggregate' /// '__trivially_copyable' /// /// binary-type-trait: /// [GNU] '__is_base_of' /// [MS] '__is_convertible_to' /// '__is_convertible' /// '__is_same' /// /// [Embarcadero] array-type-trait: /// '__array_rank' /// '__array_extent' /// /// [Embarcadero] expression-trait: /// '__is_lvalue_expr' /// '__is_rvalue_expr' /// \endverbatim /// ExprResult Parser::ParseCastExpression(bool isUnaryExpression, bool isAddressOfOperand, bool &NotCastExpr, TypeCastState isTypeCast, bool isVectorLiteral) { ExprResult Res; tok::TokenKind SavedKind = Tok.getKind(); NotCastExpr = false; // This handles all of cast-expression, unary-expression, postfix-expression, // and primary-expression. We handle them together like this for efficiency // and to simplify handling of an expression starting with a '(' token: which // may be one of a parenthesized expression, cast-expression, compound literal // expression, or statement expression. // // If the parsed tokens consist of a primary-expression, the cases below // break out of the switch; at the end we call ParsePostfixExpressionSuffix // to handle the postfix expression suffixes. Cases that cannot be followed // by postfix exprs should return without invoking // ParsePostfixExpressionSuffix. switch (SavedKind) { case tok::l_paren: { // If this expression is limited to being a unary-expression, the parent can // not start a cast expression. ParenParseOption ParenExprType = (isUnaryExpression && !getLangOpts().CPlusPlus) ? CompoundLiteral : CastExpr; ParsedType CastTy; SourceLocation RParenLoc; Res = ParseParenExpression(ParenExprType, false/*stopIfCastExr*/, isTypeCast == IsTypeCast, CastTy, RParenLoc); if (isVectorLiteral) return Res; switch (ParenExprType) { case SimpleExpr: break; // Nothing else to do. case CompoundStmt: break; // Nothing else to do. case CompoundLiteral: // We parsed '(' type-name ')' '{' ... '}'. If any suffixes of // postfix-expression exist, parse them now. break; case CastExpr: // We have parsed the cast-expression and no postfix-expr pieces are // following. return Res; } break; } // primary-expression case tok::numeric_constant: // constant: integer-constant // constant: floating-constant Res = Actions.ActOnNumericConstant(Tok, /*UDLScope*/getCurScope()); ConsumeToken(); break; case tok::kw_true: case tok::kw_false: Res = ParseCXXBoolLiteral(); break; case tok::kw___objc_yes: case tok::kw___objc_no: return ParseObjCBoolLiteral(); case tok::kw_nullptr: Diag(Tok, diag::warn_cxx98_compat_nullptr); return Actions.ActOnCXXNullPtrLiteral(ConsumeToken()); case tok::annot_primary_expr: assert(Res.get() == nullptr && "Stray primary-expression annotation?"); Res = getExprAnnotation(Tok); ConsumeAnnotationToken(); if (!Res.isInvalid() && Tok.is(tok::less)) checkPotentialAngleBracket(Res); break; case tok::kw___super: case tok::kw_decltype: // Annotate the token and tail recurse. if (TryAnnotateTypeOrScopeToken()) return ExprError(); assert(Tok.isNot(tok::kw_decltype) && Tok.isNot(tok::kw___super)); return ParseCastExpression(isUnaryExpression, isAddressOfOperand); case tok::identifier: { // primary-expression: identifier // unqualified-id: identifier // constant: enumeration-constant // Turn a potentially qualified name into a annot_typename or // annot_cxxscope if it would be valid. This handles things like x::y, etc. if (getLangOpts().CPlusPlus) { // Avoid the unnecessary parse-time lookup in the common case // where the syntax forbids a type. const Token &Next = NextToken(); // If this identifier was reverted from a token ID, and the next token // is a parenthesis, this is likely to be a use of a type trait. Check // those tokens. if (Next.is(tok::l_paren) && Tok.is(tok::identifier) && Tok.getIdentifierInfo()->hasRevertedTokenIDToIdentifier()) { IdentifierInfo *II = Tok.getIdentifierInfo(); // Build up the mapping of revertible type traits, for future use. if (RevertibleTypeTraits.empty()) { #define RTT_JOIN(X,Y) X##Y #define REVERTIBLE_TYPE_TRAIT(Name) \ RevertibleTypeTraits[PP.getIdentifierInfo(#Name)] \ = RTT_JOIN(tok::kw_,Name) REVERTIBLE_TYPE_TRAIT(__is_abstract); REVERTIBLE_TYPE_TRAIT(__is_aggregate); REVERTIBLE_TYPE_TRAIT(__is_arithmetic); REVERTIBLE_TYPE_TRAIT(__is_array); REVERTIBLE_TYPE_TRAIT(__is_assignable); REVERTIBLE_TYPE_TRAIT(__is_base_of); REVERTIBLE_TYPE_TRAIT(__is_class); REVERTIBLE_TYPE_TRAIT(__is_complete_type); REVERTIBLE_TYPE_TRAIT(__is_compound); REVERTIBLE_TYPE_TRAIT(__is_const); REVERTIBLE_TYPE_TRAIT(__is_constructible); REVERTIBLE_TYPE_TRAIT(__is_convertible); REVERTIBLE_TYPE_TRAIT(__is_convertible_to); REVERTIBLE_TYPE_TRAIT(__is_destructible); REVERTIBLE_TYPE_TRAIT(__is_empty); REVERTIBLE_TYPE_TRAIT(__is_enum); REVERTIBLE_TYPE_TRAIT(__is_floating_point); REVERTIBLE_TYPE_TRAIT(__is_final); REVERTIBLE_TYPE_TRAIT(__is_function); REVERTIBLE_TYPE_TRAIT(__is_fundamental); REVERTIBLE_TYPE_TRAIT(__is_integral); REVERTIBLE_TYPE_TRAIT(__is_interface_class); REVERTIBLE_TYPE_TRAIT(__is_literal); REVERTIBLE_TYPE_TRAIT(__is_lvalue_expr); REVERTIBLE_TYPE_TRAIT(__is_lvalue_reference); REVERTIBLE_TYPE_TRAIT(__is_member_function_pointer); REVERTIBLE_TYPE_TRAIT(__is_member_object_pointer); REVERTIBLE_TYPE_TRAIT(__is_member_pointer); REVERTIBLE_TYPE_TRAIT(__is_nothrow_assignable); REVERTIBLE_TYPE_TRAIT(__is_nothrow_constructible); REVERTIBLE_TYPE_TRAIT(__is_nothrow_destructible); REVERTIBLE_TYPE_TRAIT(__is_object); REVERTIBLE_TYPE_TRAIT(__is_pod); REVERTIBLE_TYPE_TRAIT(__is_pointer); REVERTIBLE_TYPE_TRAIT(__is_polymorphic); REVERTIBLE_TYPE_TRAIT(__is_reference); REVERTIBLE_TYPE_TRAIT(__is_rvalue_expr); REVERTIBLE_TYPE_TRAIT(__is_rvalue_reference); REVERTIBLE_TYPE_TRAIT(__is_same); REVERTIBLE_TYPE_TRAIT(__is_scalar); REVERTIBLE_TYPE_TRAIT(__is_sealed); REVERTIBLE_TYPE_TRAIT(__is_signed); REVERTIBLE_TYPE_TRAIT(__is_standard_layout); REVERTIBLE_TYPE_TRAIT(__is_trivial); REVERTIBLE_TYPE_TRAIT(__is_trivially_assignable); REVERTIBLE_TYPE_TRAIT(__is_trivially_constructible); REVERTIBLE_TYPE_TRAIT(__is_trivially_copyable); REVERTIBLE_TYPE_TRAIT(__is_union); REVERTIBLE_TYPE_TRAIT(__is_unsigned); REVERTIBLE_TYPE_TRAIT(__is_void); REVERTIBLE_TYPE_TRAIT(__is_volatile); #undef REVERTIBLE_TYPE_TRAIT #undef RTT_JOIN } // If we find that this is in fact the name of a type trait, // update the token kind in place and parse again to treat it as // the appropriate kind of type trait. llvm::SmallDenseMap::iterator Known = RevertibleTypeTraits.find(II); if (Known != RevertibleTypeTraits.end()) { Tok.setKind(Known->second); return ParseCastExpression(isUnaryExpression, isAddressOfOperand, NotCastExpr, isTypeCast); } } if ((!ColonIsSacred && Next.is(tok::colon)) || Next.isOneOf(tok::coloncolon, tok::less, tok::l_paren, tok::l_brace)) { // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. if (TryAnnotateTypeOrScopeToken()) return ExprError(); if (!Tok.is(tok::identifier)) return ParseCastExpression(isUnaryExpression, isAddressOfOperand); } } // Consume the identifier so that we can see if it is followed by a '(' or // '.'. IdentifierInfo &II = *Tok.getIdentifierInfo(); SourceLocation ILoc = ConsumeToken(); // Support 'Class.property' and 'super.property' notation. if (getLangOpts().ObjC1 && Tok.is(tok::period) && (Actions.getTypeName(II, ILoc, getCurScope()) || // Allow the base to be 'super' if in an objc-method. (&II == Ident_super && getCurScope()->isInObjcMethodScope()))) { ConsumeToken(); if (Tok.is(tok::code_completion) && &II != Ident_super) { Actions.CodeCompleteObjCClassPropertyRefExpr( getCurScope(), II, ILoc, ExprStatementTokLoc == ILoc); cutOffParsing(); return ExprError(); } // Allow either an identifier or the keyword 'class' (in C++). if (Tok.isNot(tok::identifier) && !(getLangOpts().CPlusPlus && Tok.is(tok::kw_class))) { Diag(Tok, diag::err_expected_property_name); return ExprError(); } IdentifierInfo &PropertyName = *Tok.getIdentifierInfo(); SourceLocation PropertyLoc = ConsumeToken(); Res = Actions.ActOnClassPropertyRefExpr(II, PropertyName, ILoc, PropertyLoc); break; } // In an Objective-C method, if we have "super" followed by an identifier, // the token sequence is ill-formed. However, if there's a ':' or ']' after // that identifier, this is probably a message send with a missing open // bracket. Treat it as such. if (getLangOpts().ObjC1 && &II == Ident_super && !InMessageExpression && getCurScope()->isInObjcMethodScope() && ((Tok.is(tok::identifier) && (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) || Tok.is(tok::code_completion))) { Res = ParseObjCMessageExpressionBody(SourceLocation(), ILoc, nullptr, nullptr); break; } // If we have an Objective-C class name followed by an identifier // and either ':' or ']', this is an Objective-C class message // send that's missing the opening '['. Recovery // appropriately. Also take this path if we're performing code // completion after an Objective-C class name. if (getLangOpts().ObjC1 && ((Tok.is(tok::identifier) && !InMessageExpression) || Tok.is(tok::code_completion))) { const Token& Next = NextToken(); if (Tok.is(tok::code_completion) || Next.is(tok::colon) || Next.is(tok::r_square)) if (ParsedType Typ = Actions.getTypeName(II, ILoc, getCurScope())) if (Typ.get()->isObjCObjectOrInterfaceType()) { // Fake up a Declarator to use with ActOnTypeName. DeclSpec DS(AttrFactory); DS.SetRangeStart(ILoc); DS.SetRangeEnd(ILoc); const char *PrevSpec = nullptr; unsigned DiagID; DS.SetTypeSpecType(TST_typename, ILoc, PrevSpec, DiagID, Typ, Actions.getASTContext().getPrintingPolicy()); Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext); TypeResult Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); if (Ty.isInvalid()) break; Res = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), Ty.get(), nullptr); break; } } // Make sure to pass down the right value for isAddressOfOperand. if (isAddressOfOperand && isPostfixExpressionSuffixStart()) isAddressOfOperand = false; // Function designators are allowed to be undeclared (C99 6.5.1p2), so we // need to know whether or not this identifier is a function designator or // not. UnqualifiedId Name; CXXScopeSpec ScopeSpec; SourceLocation TemplateKWLoc; Token Replacement; auto Validator = llvm::make_unique( Tok, isTypeCast != NotTypeCast, isTypeCast != IsTypeCast); Validator->IsAddressOfOperand = isAddressOfOperand; if (Tok.isOneOf(tok::periodstar, tok::arrowstar)) { Validator->WantExpressionKeywords = false; Validator->WantRemainingKeywords = false; } else { Validator->WantRemainingKeywords = Tok.isNot(tok::r_paren); } Name.setIdentifier(&II, ILoc); Res = Actions.ActOnIdExpression( getCurScope(), ScopeSpec, TemplateKWLoc, Name, Tok.is(tok::l_paren), isAddressOfOperand, std::move(Validator), /*IsInlineAsmIdentifier=*/false, Tok.is(tok::r_paren) ? nullptr : &Replacement); if (!Res.isInvalid() && Res.isUnset()) { UnconsumeToken(Replacement); return ParseCastExpression(isUnaryExpression, isAddressOfOperand, NotCastExpr, isTypeCast); } if (!Res.isInvalid() && Tok.is(tok::less)) checkPotentialAngleBracket(Res); break; } case tok::char_constant: // constant: character-constant case tok::wide_char_constant: case tok::utf8_char_constant: case tok::utf16_char_constant: case tok::utf32_char_constant: Res = Actions.ActOnCharacterConstant(Tok, /*UDLScope*/getCurScope()); ConsumeToken(); break; case tok::kw___func__: // primary-expression: __func__ [C99 6.4.2.2] case tok::kw___FUNCTION__: // primary-expression: __FUNCTION__ [GNU] case tok::kw___FUNCDNAME__: // primary-expression: __FUNCDNAME__ [MS] case tok::kw___FUNCSIG__: // primary-expression: __FUNCSIG__ [MS] case tok::kw_L__FUNCTION__: // primary-expression: L__FUNCTION__ [MS] case tok::kw___PRETTY_FUNCTION__: // primary-expression: __P..Y_F..N__ [GNU] Res = Actions.ActOnPredefinedExpr(Tok.getLocation(), SavedKind); ConsumeToken(); break; case tok::string_literal: // primary-expression: string-literal case tok::wide_string_literal: case tok::utf8_string_literal: case tok::utf16_string_literal: case tok::utf32_string_literal: Res = ParseStringLiteralExpression(true); break; case tok::kw__Generic: // primary-expression: generic-selection [C11 6.5.1] Res = ParseGenericSelectionExpression(); break; case tok::kw___builtin_available: return ParseAvailabilityCheckExpr(Tok.getLocation()); case tok::kw___builtin_va_arg: case tok::kw___builtin_offsetof: case tok::kw___builtin_choose_expr: case tok::kw___builtin_astype: // primary-expression: [OCL] as_type() case tok::kw___builtin_convertvector: return ParseBuiltinPrimaryExpression(); case tok::kw___null: return Actions.ActOnGNUNullExpr(ConsumeToken()); case tok::plusplus: // unary-expression: '++' unary-expression [C99] case tok::minusminus: { // unary-expression: '--' unary-expression [C99] // C++ [expr.unary] has: // unary-expression: // ++ cast-expression // -- cast-expression Token SavedTok = Tok; ConsumeToken(); // One special case is implicitly handled here: if the preceding tokens are // an ambiguous cast expression, such as "(T())++", then we recurse to // determine whether the '++' is prefix or postfix. Res = ParseCastExpression(!getLangOpts().CPlusPlus, /*isAddressOfOperand*/false, NotCastExpr, NotTypeCast); if (NotCastExpr) { // If we return with NotCastExpr = true, we must not consume any tokens, // so put the token back where we found it. assert(Res.isInvalid()); UnconsumeToken(SavedTok); return ExprError(); } if (!Res.isInvalid()) Res = Actions.ActOnUnaryOp(getCurScope(), SavedTok.getLocation(), SavedKind, Res.get()); return Res; } case tok::amp: { // unary-expression: '&' cast-expression // Special treatment because of member pointers SourceLocation SavedLoc = ConsumeToken(); Res = ParseCastExpression(false, true); if (!Res.isInvalid()) Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); return Res; } case tok::star: // unary-expression: '*' cast-expression case tok::plus: // unary-expression: '+' cast-expression case tok::minus: // unary-expression: '-' cast-expression case tok::tilde: // unary-expression: '~' cast-expression case tok::exclaim: // unary-expression: '!' cast-expression case tok::kw___real: // unary-expression: '__real' cast-expression [GNU] case tok::kw___imag: { // unary-expression: '__imag' cast-expression [GNU] SourceLocation SavedLoc = ConsumeToken(); Res = ParseCastExpression(false); if (!Res.isInvalid()) Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); return Res; } case tok::kw_co_await: { // unary-expression: 'co_await' cast-expression SourceLocation CoawaitLoc = ConsumeToken(); Res = ParseCastExpression(false); if (!Res.isInvalid()) Res = Actions.ActOnCoawaitExpr(getCurScope(), CoawaitLoc, Res.get()); return Res; } case tok::kw___extension__:{//unary-expression:'__extension__' cast-expr [GNU] // __extension__ silences extension warnings in the subexpression. ExtensionRAIIObject O(Diags); // Use RAII to do this. SourceLocation SavedLoc = ConsumeToken(); Res = ParseCastExpression(false); if (!Res.isInvalid()) Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); return Res; } case tok::kw__Alignof: // unary-expression: '_Alignof' '(' type-name ')' if (!getLangOpts().C11) Diag(Tok, diag::ext_c11_alignment) << Tok.getName(); // fallthrough case tok::kw_alignof: // unary-expression: 'alignof' '(' type-id ')' case tok::kw___alignof: // unary-expression: '__alignof' unary-expression // unary-expression: '__alignof' '(' type-name ')' case tok::kw_sizeof: // unary-expression: 'sizeof' unary-expression // unary-expression: 'sizeof' '(' type-name ')' case tok::kw_vec_step: // unary-expression: OpenCL 'vec_step' expression // unary-expression: '__builtin_omp_required_simd_align' '(' type-name ')' case tok::kw___builtin_omp_required_simd_align: return ParseUnaryExprOrTypeTraitExpression(); case tok::ampamp: { // unary-expression: '&&' identifier SourceLocation AmpAmpLoc = ConsumeToken(); if (Tok.isNot(tok::identifier)) return ExprError(Diag(Tok, diag::err_expected) << tok::identifier); if (getCurScope()->getFnParent() == nullptr) return ExprError(Diag(Tok, diag::err_address_of_label_outside_fn)); Diag(AmpAmpLoc, diag::ext_gnu_address_of_label); LabelDecl *LD = Actions.LookupOrCreateLabel(Tok.getIdentifierInfo(), Tok.getLocation()); Res = Actions.ActOnAddrLabel(AmpAmpLoc, Tok.getLocation(), LD); ConsumeToken(); return Res; } case tok::kw_const_cast: case tok::kw_dynamic_cast: case tok::kw_reinterpret_cast: case tok::kw_static_cast: Res = ParseCXXCasts(); break; case tok::kw_typeid: Res = ParseCXXTypeid(); break; case tok::kw___uuidof: Res = ParseCXXUuidof(); break; case tok::kw_this: Res = ParseCXXThis(); break; case tok::annot_typename: if (isStartOfObjCClassMessageMissingOpenBracket()) { ParsedType Type = getTypeAnnotation(Tok); // Fake up a Declarator to use with ActOnTypeName. DeclSpec DS(AttrFactory); DS.SetRangeStart(Tok.getLocation()); DS.SetRangeEnd(Tok.getLastLoc()); const char *PrevSpec = nullptr; unsigned DiagID; DS.SetTypeSpecType(TST_typename, Tok.getAnnotationEndLoc(), PrevSpec, DiagID, Type, Actions.getASTContext().getPrintingPolicy()); Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext); TypeResult Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); if (Ty.isInvalid()) break; ConsumeAnnotationToken(); Res = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), Ty.get(), nullptr); break; } // Fall through case tok::annot_decltype: case tok::kw_char: case tok::kw_wchar_t: case tok::kw_char8_t: case tok::kw_char16_t: case tok::kw_char32_t: case tok::kw_bool: case tok::kw_short: case tok::kw_int: case tok::kw_long: case tok::kw___int64: case tok::kw___int128: case tok::kw_signed: case tok::kw_unsigned: case tok::kw_half: case tok::kw_float: case tok::kw_double: case tok::kw__Float16: case tok::kw___float128: case tok::kw_void: case tok::kw_typename: case tok::kw_typeof: case tok::kw___vector: #define GENERIC_IMAGE_TYPE(ImgType, Id) case tok::kw_##ImgType##_t: #include "clang/Basic/OpenCLImageTypes.def" { if (!getLangOpts().CPlusPlus) { Diag(Tok, diag::err_expected_expression); return ExprError(); } if (SavedKind == tok::kw_typename) { // postfix-expression: typename-specifier '(' expression-list[opt] ')' // typename-specifier braced-init-list if (TryAnnotateTypeOrScopeToken()) return ExprError(); if (!Actions.isSimpleTypeSpecifier(Tok.getKind())) // We are trying to parse a simple-type-specifier but might not get such // a token after error recovery. return ExprError(); } // postfix-expression: simple-type-specifier '(' expression-list[opt] ')' // simple-type-specifier braced-init-list // DeclSpec DS(AttrFactory); ParseCXXSimpleTypeSpecifier(DS); if (Tok.isNot(tok::l_paren) && (!getLangOpts().CPlusPlus11 || Tok.isNot(tok::l_brace))) return ExprError(Diag(Tok, diag::err_expected_lparen_after_type) << DS.getSourceRange()); if (Tok.is(tok::l_brace)) Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); Res = ParseCXXTypeConstructExpression(DS); break; } case tok::annot_cxxscope: { // [C++] id-expression: qualified-id // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. // (We can end up in this situation after tentative parsing.) if (TryAnnotateTypeOrScopeToken()) return ExprError(); if (!Tok.is(tok::annot_cxxscope)) return ParseCastExpression(isUnaryExpression, isAddressOfOperand, NotCastExpr, isTypeCast); Token Next = NextToken(); if (Next.is(tok::annot_template_id)) { TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Next); if (TemplateId->Kind == TNK_Type_template) { // We have a qualified template-id that we know refers to a // type, translate it into a type and continue parsing as a // cast expression. CXXScopeSpec SS; ParseOptionalCXXScopeSpecifier(SS, nullptr, /*EnteringContext=*/false); AnnotateTemplateIdTokenAsType(); return ParseCastExpression(isUnaryExpression, isAddressOfOperand, NotCastExpr, isTypeCast); } } // Parse as an id-expression. Res = ParseCXXIdExpression(isAddressOfOperand); break; } case tok::annot_template_id: { // [C++] template-id TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok); if (TemplateId->Kind == TNK_Type_template) { // We have a template-id that we know refers to a type, // translate it into a type and continue parsing as a cast // expression. AnnotateTemplateIdTokenAsType(); return ParseCastExpression(isUnaryExpression, isAddressOfOperand, NotCastExpr, isTypeCast); } // Fall through to treat the template-id as an id-expression. LLVM_FALLTHROUGH; } case tok::kw_operator: // [C++] id-expression: operator/conversion-function-id Res = ParseCXXIdExpression(isAddressOfOperand); break; case tok::coloncolon: { // ::foo::bar -> global qualified name etc. If TryAnnotateTypeOrScopeToken // annotates the token, tail recurse. if (TryAnnotateTypeOrScopeToken()) return ExprError(); if (!Tok.is(tok::coloncolon)) return ParseCastExpression(isUnaryExpression, isAddressOfOperand); // ::new -> [C++] new-expression // ::delete -> [C++] delete-expression SourceLocation CCLoc = ConsumeToken(); if (Tok.is(tok::kw_new)) return ParseCXXNewExpression(true, CCLoc); if (Tok.is(tok::kw_delete)) return ParseCXXDeleteExpression(true, CCLoc); // This is not a type name or scope specifier, it is an invalid expression. Diag(CCLoc, diag::err_expected_expression); return ExprError(); } case tok::kw_new: // [C++] new-expression return ParseCXXNewExpression(false, Tok.getLocation()); case tok::kw_delete: // [C++] delete-expression return ParseCXXDeleteExpression(false, Tok.getLocation()); case tok::kw_noexcept: { // [C++0x] 'noexcept' '(' expression ')' Diag(Tok, diag::warn_cxx98_compat_noexcept_expr); SourceLocation KeyLoc = ConsumeToken(); BalancedDelimiterTracker T(*this, tok::l_paren); if (T.expectAndConsume(diag::err_expected_lparen_after, "noexcept")) return ExprError(); // C++11 [expr.unary.noexcept]p1: // The noexcept operator determines whether the evaluation of its operand, // which is an unevaluated operand, can throw an exception. EnterExpressionEvaluationContext Unevaluated( Actions, Sema::ExpressionEvaluationContext::Unevaluated); ExprResult Result = ParseExpression(); T.consumeClose(); if (!Result.isInvalid()) Result = Actions.ActOnNoexceptExpr(KeyLoc, T.getOpenLocation(), Result.get(), T.getCloseLocation()); return Result; } #define TYPE_TRAIT(N,Spelling,K) \ case tok::kw_##Spelling: #include "clang/Basic/TokenKinds.def" return ParseTypeTrait(); case tok::kw___array_rank: case tok::kw___array_extent: return ParseArrayTypeTrait(); case tok::kw___is_lvalue_expr: case tok::kw___is_rvalue_expr: return ParseExpressionTrait(); case tok::at: { SourceLocation AtLoc = ConsumeToken(); return ParseObjCAtExpression(AtLoc); } case tok::caret: Res = ParseBlockLiteralExpression(); break; case tok::code_completion: { Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); cutOffParsing(); return ExprError(); } case tok::l_square: if (getLangOpts().CPlusPlus11) { if (getLangOpts().ObjC1) { // C++11 lambda expressions and Objective-C message sends both start with a // square bracket. There are three possibilities here: // we have a valid lambda expression, we have an invalid lambda // expression, or we have something that doesn't appear to be a lambda. // If we're in the last case, we fall back to ParseObjCMessageExpression. Res = TryParseLambdaExpression(); if (!Res.isInvalid() && !Res.get()) Res = ParseObjCMessageExpression(); break; } Res = ParseLambdaExpression(); break; } if (getLangOpts().ObjC1) { Res = ParseObjCMessageExpression(); break; } // FALL THROUGH. default: NotCastExpr = true; return ExprError(); } // Check to see whether Res is a function designator only. If it is and we // are compiling for OpenCL, we need to return an error as this implies // that the address of the function is being taken, which is illegal in CL. // These can be followed by postfix-expr pieces. Res = ParsePostfixExpressionSuffix(Res); if (getLangOpts().OpenCL) if (Expr *PostfixExpr = Res.get()) { QualType Ty = PostfixExpr->getType(); if (!Ty.isNull() && Ty->isFunctionType()) { Diag(PostfixExpr->getExprLoc(), diag::err_opencl_taking_function_address_parser); return ExprError(); } } return Res; } /// Once the leading part of a postfix-expression is parsed, this /// method parses any suffixes that apply. /// /// \verbatim /// postfix-expression: [C99 6.5.2] /// primary-expression /// postfix-expression '[' expression ']' /// postfix-expression '[' braced-init-list ']' /// postfix-expression '(' argument-expression-list[opt] ')' /// postfix-expression '.' identifier /// postfix-expression '->' identifier /// postfix-expression '++' /// postfix-expression '--' /// '(' type-name ')' '{' initializer-list '}' /// '(' type-name ')' '{' initializer-list ',' '}' /// /// argument-expression-list: [C99 6.5.2] /// argument-expression ...[opt] /// argument-expression-list ',' assignment-expression ...[opt] /// \endverbatim ExprResult Parser::ParsePostfixExpressionSuffix(ExprResult LHS) { // Now that the primary-expression piece of the postfix-expression has been // parsed, see if there are any postfix-expression pieces here. SourceLocation Loc; while (1) { switch (Tok.getKind()) { case tok::code_completion: if (InMessageExpression) return LHS; Actions.CodeCompletePostfixExpression(getCurScope(), LHS); cutOffParsing(); return ExprError(); case tok::identifier: // If we see identifier: after an expression, and we're not already in a // message send, then this is probably a message send with a missing // opening bracket '['. if (getLangOpts().ObjC1 && !InMessageExpression && (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) { LHS = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), nullptr, LHS.get()); break; } // Fall through; this isn't a message send. LLVM_FALLTHROUGH; default: // Not a postfix-expression suffix. return LHS; case tok::l_square: { // postfix-expression: p-e '[' expression ']' // If we have a array postfix expression that starts on a new line and // Objective-C is enabled, it is highly likely that the user forgot a // semicolon after the base expression and that the array postfix-expr is // actually another message send. In this case, do some look-ahead to see // if the contents of the square brackets are obviously not a valid // expression and recover by pretending there is no suffix. if (getLangOpts().ObjC1 && Tok.isAtStartOfLine() && isSimpleObjCMessageExpression()) return LHS; // Reject array indices starting with a lambda-expression. '[[' is // reserved for attributes. if (CheckProhibitedCXX11Attribute()) { (void)Actions.CorrectDelayedTyposInExpr(LHS); return ExprError(); } BalancedDelimiterTracker T(*this, tok::l_square); T.consumeOpen(); Loc = T.getOpenLocation(); ExprResult Idx, Length; SourceLocation ColonLoc; if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) { Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); Idx = ParseBraceInitializer(); } else if (getLangOpts().OpenMP) { ColonProtectionRAIIObject RAII(*this); // Parse [: or [ expr or [ expr : if (!Tok.is(tok::colon)) { // [ expr Idx = ParseExpression(); } if (Tok.is(tok::colon)) { // Consume ':' ColonLoc = ConsumeToken(); if (Tok.isNot(tok::r_square)) Length = ParseExpression(); } } else Idx = ParseExpression(); SourceLocation RLoc = Tok.getLocation(); ExprResult OrigLHS = LHS; if (!LHS.isInvalid() && !Idx.isInvalid() && !Length.isInvalid() && Tok.is(tok::r_square)) { if (ColonLoc.isValid()) { LHS = Actions.ActOnOMPArraySectionExpr(LHS.get(), Loc, Idx.get(), ColonLoc, Length.get(), RLoc); } else { LHS = Actions.ActOnArraySubscriptExpr(getCurScope(), LHS.get(), Loc, Idx.get(), RLoc); } } else { LHS = ExprError(); } if (LHS.isInvalid()) { (void)Actions.CorrectDelayedTyposInExpr(OrigLHS); (void)Actions.CorrectDelayedTyposInExpr(Idx); (void)Actions.CorrectDelayedTyposInExpr(Length); LHS = ExprError(); Idx = ExprError(); } // Match the ']'. T.consumeClose(); break; } case tok::l_paren: // p-e: p-e '(' argument-expression-list[opt] ')' case tok::lesslessless: { // p-e: p-e '<<<' argument-expression-list '>>>' // '(' argument-expression-list[opt] ')' tok::TokenKind OpKind = Tok.getKind(); InMessageExpressionRAIIObject InMessage(*this, false); Expr *ExecConfig = nullptr; BalancedDelimiterTracker PT(*this, tok::l_paren); if (OpKind == tok::lesslessless) { ExprVector ExecConfigExprs; CommaLocsTy ExecConfigCommaLocs; SourceLocation OpenLoc = ConsumeToken(); if (ParseSimpleExpressionList(ExecConfigExprs, ExecConfigCommaLocs)) { (void)Actions.CorrectDelayedTyposInExpr(LHS); LHS = ExprError(); } SourceLocation CloseLoc; if (TryConsumeToken(tok::greatergreatergreater, CloseLoc)) { } else if (LHS.isInvalid()) { SkipUntil(tok::greatergreatergreater, StopAtSemi); } else { // There was an error closing the brackets Diag(Tok, diag::err_expected) << tok::greatergreatergreater; Diag(OpenLoc, diag::note_matching) << tok::lesslessless; SkipUntil(tok::greatergreatergreater, StopAtSemi); LHS = ExprError(); } if (!LHS.isInvalid()) { if (ExpectAndConsume(tok::l_paren)) LHS = ExprError(); else Loc = PrevTokLocation; } if (!LHS.isInvalid()) { ExprResult ECResult = Actions.ActOnCUDAExecConfigExpr(getCurScope(), OpenLoc, ExecConfigExprs, CloseLoc); if (ECResult.isInvalid()) LHS = ExprError(); else ExecConfig = ECResult.get(); } } else { PT.consumeOpen(); Loc = PT.getOpenLocation(); } ExprVector ArgExprs; CommaLocsTy CommaLocs; if (Tok.is(tok::code_completion)) { Actions.CodeCompleteCall(getCurScope(), LHS.get(), None); cutOffParsing(); return ExprError(); } if (OpKind == tok::l_paren || !LHS.isInvalid()) { if (Tok.isNot(tok::r_paren)) { if (ParseExpressionList(ArgExprs, CommaLocs, [&] { Actions.CodeCompleteCall(getCurScope(), LHS.get(), ArgExprs); })) { (void)Actions.CorrectDelayedTyposInExpr(LHS); LHS = ExprError(); } else if (LHS.isInvalid()) { for (auto &E : ArgExprs) Actions.CorrectDelayedTyposInExpr(E); } } } // Match the ')'. if (LHS.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); } else if (Tok.isNot(tok::r_paren)) { bool HadDelayedTypo = false; if (Actions.CorrectDelayedTyposInExpr(LHS).get() != LHS.get()) HadDelayedTypo = true; for (auto &E : ArgExprs) if (Actions.CorrectDelayedTyposInExpr(E).get() != E) HadDelayedTypo = true; // If there were delayed typos in the LHS or ArgExprs, call SkipUntil // instead of PT.consumeClose() to avoid emitting extra diagnostics for // the unmatched l_paren. if (HadDelayedTypo) SkipUntil(tok::r_paren, StopAtSemi); else PT.consumeClose(); LHS = ExprError(); } else { assert((ArgExprs.size() == 0 || ArgExprs.size()-1 == CommaLocs.size())&& "Unexpected number of commas!"); LHS = Actions.ActOnCallExpr(getCurScope(), LHS.get(), Loc, ArgExprs, Tok.getLocation(), ExecConfig); PT.consumeClose(); } break; } case tok::arrow: case tok::period: { // postfix-expression: p-e '->' template[opt] id-expression // postfix-expression: p-e '.' template[opt] id-expression tok::TokenKind OpKind = Tok.getKind(); SourceLocation OpLoc = ConsumeToken(); // Eat the "." or "->" token. CXXScopeSpec SS; ParsedType ObjectType; bool MayBePseudoDestructor = false; Expr* OrigLHS = !LHS.isInvalid() ? LHS.get() : nullptr; if (getLangOpts().CPlusPlus && !LHS.isInvalid()) { Expr *Base = OrigLHS; const Type* BaseType = Base->getType().getTypePtrOrNull(); if (BaseType && Tok.is(tok::l_paren) && (BaseType->isFunctionType() || BaseType->isSpecificPlaceholderType(BuiltinType::BoundMember))) { Diag(OpLoc, diag::err_function_is_not_record) << OpKind << Base->getSourceRange() << FixItHint::CreateRemoval(OpLoc); return ParsePostfixExpressionSuffix(Base); } LHS = Actions.ActOnStartCXXMemberReference(getCurScope(), Base, OpLoc, OpKind, ObjectType, MayBePseudoDestructor); if (LHS.isInvalid()) break; ParseOptionalCXXScopeSpecifier(SS, ObjectType, /*EnteringContext=*/false, &MayBePseudoDestructor); if (SS.isNotEmpty()) ObjectType = nullptr; } if (Tok.is(tok::code_completion)) { tok::TokenKind CorrectedOpKind = OpKind == tok::arrow ? tok::period : tok::arrow; ExprResult CorrectedLHS(/*IsInvalid=*/true); if (getLangOpts().CPlusPlus && OrigLHS) { const bool DiagsAreSuppressed = Diags.getSuppressAllDiagnostics(); Diags.setSuppressAllDiagnostics(true); CorrectedLHS = Actions.ActOnStartCXXMemberReference( getCurScope(), OrigLHS, OpLoc, CorrectedOpKind, ObjectType, MayBePseudoDestructor); Diags.setSuppressAllDiagnostics(DiagsAreSuppressed); } Expr *Base = LHS.get(); Expr *CorrectedBase = CorrectedLHS.get(); // Code completion for a member access expression. Actions.CodeCompleteMemberReferenceExpr( getCurScope(), Base, CorrectedBase, OpLoc, OpKind == tok::arrow, Base && ExprStatementTokLoc == Base->getLocStart()); cutOffParsing(); return ExprError(); } if (MayBePseudoDestructor && !LHS.isInvalid()) { LHS = ParseCXXPseudoDestructor(LHS.get(), OpLoc, OpKind, SS, ObjectType); break; } // Either the action has told us that this cannot be a // pseudo-destructor expression (based on the type of base // expression), or we didn't see a '~' in the right place. We // can still parse a destructor name here, but in that case it // names a real destructor. // Allow explicit constructor calls in Microsoft mode. // FIXME: Add support for explicit call of template constructor. SourceLocation TemplateKWLoc; UnqualifiedId Name; if (getLangOpts().ObjC2 && OpKind == tok::period && Tok.is(tok::kw_class)) { // Objective-C++: // After a '.' in a member access expression, treat the keyword // 'class' as if it were an identifier. // // This hack allows property access to the 'class' method because it is // such a common method name. For other C++ keywords that are // Objective-C method names, one must use the message send syntax. IdentifierInfo *Id = Tok.getIdentifierInfo(); SourceLocation Loc = ConsumeToken(); Name.setIdentifier(Id, Loc); } else if (ParseUnqualifiedId(SS, /*EnteringContext=*/false, /*AllowDestructorName=*/true, /*AllowConstructorName=*/ getLangOpts().MicrosoftExt, /*AllowDeductionGuide=*/false, ObjectType, &TemplateKWLoc, Name)) { (void)Actions.CorrectDelayedTyposInExpr(LHS); LHS = ExprError(); } if (!LHS.isInvalid()) LHS = Actions.ActOnMemberAccessExpr(getCurScope(), LHS.get(), OpLoc, OpKind, SS, TemplateKWLoc, Name, CurParsedObjCImpl ? CurParsedObjCImpl->Dcl : nullptr); if (!LHS.isInvalid() && Tok.is(tok::less)) checkPotentialAngleBracket(LHS); break; } case tok::plusplus: // postfix-expression: postfix-expression '++' case tok::minusminus: // postfix-expression: postfix-expression '--' if (!LHS.isInvalid()) { LHS = Actions.ActOnPostfixUnaryOp(getCurScope(), Tok.getLocation(), Tok.getKind(), LHS.get()); } ConsumeToken(); break; } } } /// ParseExprAfterUnaryExprOrTypeTrait - We parsed a typeof/sizeof/alignof/ /// vec_step and we are at the start of an expression or a parenthesized /// type-id. OpTok is the operand token (typeof/sizeof/alignof). Returns the /// expression (isCastExpr == false) or the type (isCastExpr == true). /// /// \verbatim /// unary-expression: [C99 6.5.3] /// 'sizeof' unary-expression /// 'sizeof' '(' type-name ')' /// [GNU] '__alignof' unary-expression /// [GNU] '__alignof' '(' type-name ')' /// [C11] '_Alignof' '(' type-name ')' /// [C++0x] 'alignof' '(' type-id ')' /// /// [GNU] typeof-specifier: /// typeof ( expressions ) /// typeof ( type-name ) /// [GNU/C++] typeof unary-expression /// /// [OpenCL 1.1 6.11.12] vec_step built-in function: /// vec_step ( expressions ) /// vec_step ( type-name ) /// \endverbatim ExprResult Parser::ParseExprAfterUnaryExprOrTypeTrait(const Token &OpTok, bool &isCastExpr, ParsedType &CastTy, SourceRange &CastRange) { assert(OpTok.isOneOf(tok::kw_typeof, tok::kw_sizeof, tok::kw___alignof, tok::kw_alignof, tok::kw__Alignof, tok::kw_vec_step, tok::kw___builtin_omp_required_simd_align) && "Not a typeof/sizeof/alignof/vec_step expression!"); ExprResult Operand; // If the operand doesn't start with an '(', it must be an expression. if (Tok.isNot(tok::l_paren)) { // If construct allows a form without parenthesis, user may forget to put // pathenthesis around type name. if (OpTok.isOneOf(tok::kw_sizeof, tok::kw___alignof, tok::kw_alignof, tok::kw__Alignof)) { if (isTypeIdUnambiguously()) { DeclSpec DS(AttrFactory); ParseSpecifierQualifierList(DS); Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext); ParseDeclarator(DeclaratorInfo); SourceLocation LParenLoc = PP.getLocForEndOfToken(OpTok.getLocation()); SourceLocation RParenLoc = PP.getLocForEndOfToken(PrevTokLocation); Diag(LParenLoc, diag::err_expected_parentheses_around_typename) << OpTok.getName() << FixItHint::CreateInsertion(LParenLoc, "(") << FixItHint::CreateInsertion(RParenLoc, ")"); isCastExpr = true; return ExprEmpty(); } } isCastExpr = false; if (OpTok.is(tok::kw_typeof) && !getLangOpts().CPlusPlus) { Diag(Tok, diag::err_expected_after) << OpTok.getIdentifierInfo() << tok::l_paren; return ExprError(); } Operand = ParseCastExpression(true/*isUnaryExpression*/); } else { // If it starts with a '(', we know that it is either a parenthesized // type-name, or it is a unary-expression that starts with a compound // literal, or starts with a primary-expression that is a parenthesized // expression. ParenParseOption ExprType = CastExpr; SourceLocation LParenLoc = Tok.getLocation(), RParenLoc; Operand = ParseParenExpression(ExprType, true/*stopIfCastExpr*/, false, CastTy, RParenLoc); CastRange = SourceRange(LParenLoc, RParenLoc); // If ParseParenExpression parsed a '(typename)' sequence only, then this is // a type. if (ExprType == CastExpr) { isCastExpr = true; return ExprEmpty(); } if (getLangOpts().CPlusPlus || OpTok.isNot(tok::kw_typeof)) { // GNU typeof in C requires the expression to be parenthesized. Not so for // sizeof/alignof or in C++. Therefore, the parenthesized expression is // the start of a unary-expression, but doesn't include any postfix // pieces. Parse these now if present. if (!Operand.isInvalid()) Operand = ParsePostfixExpressionSuffix(Operand.get()); } } // If we get here, the operand to the typeof/sizeof/alignof was an expression. isCastExpr = false; return Operand; } /// Parse a sizeof or alignof expression. /// /// \verbatim /// unary-expression: [C99 6.5.3] /// 'sizeof' unary-expression /// 'sizeof' '(' type-name ')' /// [C++11] 'sizeof' '...' '(' identifier ')' /// [GNU] '__alignof' unary-expression /// [GNU] '__alignof' '(' type-name ')' /// [C11] '_Alignof' '(' type-name ')' /// [C++11] 'alignof' '(' type-id ')' /// \endverbatim ExprResult Parser::ParseUnaryExprOrTypeTraitExpression() { assert(Tok.isOneOf(tok::kw_sizeof, tok::kw___alignof, tok::kw_alignof, tok::kw__Alignof, tok::kw_vec_step, tok::kw___builtin_omp_required_simd_align) && "Not a sizeof/alignof/vec_step expression!"); Token OpTok = Tok; ConsumeToken(); // [C++11] 'sizeof' '...' '(' identifier ')' if (Tok.is(tok::ellipsis) && OpTok.is(tok::kw_sizeof)) { SourceLocation EllipsisLoc = ConsumeToken(); SourceLocation LParenLoc, RParenLoc; IdentifierInfo *Name = nullptr; SourceLocation NameLoc; if (Tok.is(tok::l_paren)) { BalancedDelimiterTracker T(*this, tok::l_paren); T.consumeOpen(); LParenLoc = T.getOpenLocation(); if (Tok.is(tok::identifier)) { Name = Tok.getIdentifierInfo(); NameLoc = ConsumeToken(); T.consumeClose(); RParenLoc = T.getCloseLocation(); if (RParenLoc.isInvalid()) RParenLoc = PP.getLocForEndOfToken(NameLoc); } else { Diag(Tok, diag::err_expected_parameter_pack); SkipUntil(tok::r_paren, StopAtSemi); } } else if (Tok.is(tok::identifier)) { Name = Tok.getIdentifierInfo(); NameLoc = ConsumeToken(); LParenLoc = PP.getLocForEndOfToken(EllipsisLoc); RParenLoc = PP.getLocForEndOfToken(NameLoc); Diag(LParenLoc, diag::err_paren_sizeof_parameter_pack) << Name << FixItHint::CreateInsertion(LParenLoc, "(") << FixItHint::CreateInsertion(RParenLoc, ")"); } else { Diag(Tok, diag::err_sizeof_parameter_pack); } if (!Name) return ExprError(); EnterExpressionEvaluationContext Unevaluated( Actions, Sema::ExpressionEvaluationContext::Unevaluated, Sema::ReuseLambdaContextDecl); return Actions.ActOnSizeofParameterPackExpr(getCurScope(), OpTok.getLocation(), *Name, NameLoc, RParenLoc); } if (OpTok.isOneOf(tok::kw_alignof, tok::kw__Alignof)) Diag(OpTok, diag::warn_cxx98_compat_alignof); EnterExpressionEvaluationContext Unevaluated( Actions, Sema::ExpressionEvaluationContext::Unevaluated, Sema::ReuseLambdaContextDecl); bool isCastExpr; ParsedType CastTy; SourceRange CastRange; ExprResult Operand = ParseExprAfterUnaryExprOrTypeTrait(OpTok, isCastExpr, CastTy, CastRange); UnaryExprOrTypeTrait ExprKind = UETT_SizeOf; if (OpTok.isOneOf(tok::kw_alignof, tok::kw___alignof, tok::kw__Alignof)) ExprKind = UETT_AlignOf; else if (OpTok.is(tok::kw_vec_step)) ExprKind = UETT_VecStep; else if (OpTok.is(tok::kw___builtin_omp_required_simd_align)) ExprKind = UETT_OpenMPRequiredSimdAlign; if (isCastExpr) return Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(), ExprKind, /*isType=*/true, CastTy.getAsOpaquePtr(), CastRange); if (OpTok.isOneOf(tok::kw_alignof, tok::kw__Alignof)) Diag(OpTok, diag::ext_alignof_expr) << OpTok.getIdentifierInfo(); // If we get here, the operand to the sizeof/alignof was an expression. if (!Operand.isInvalid()) Operand = Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(), ExprKind, /*isType=*/false, Operand.get(), CastRange); return Operand; } /// ParseBuiltinPrimaryExpression /// /// \verbatim /// primary-expression: [C99 6.5.1] /// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' /// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' /// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' /// assign-expr ')' /// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' /// [OCL] '__builtin_astype' '(' assignment-expression ',' type-name ')' /// /// [GNU] offsetof-member-designator: /// [GNU] identifier /// [GNU] offsetof-member-designator '.' identifier /// [GNU] offsetof-member-designator '[' expression ']' /// \endverbatim ExprResult Parser::ParseBuiltinPrimaryExpression() { ExprResult Res; const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo(); tok::TokenKind T = Tok.getKind(); SourceLocation StartLoc = ConsumeToken(); // Eat the builtin identifier. // All of these start with an open paren. if (Tok.isNot(tok::l_paren)) return ExprError(Diag(Tok, diag::err_expected_after) << BuiltinII << tok::l_paren); BalancedDelimiterTracker PT(*this, tok::l_paren); PT.consumeOpen(); // TODO: Build AST. switch (T) { default: llvm_unreachable("Not a builtin primary expression!"); case tok::kw___builtin_va_arg: { ExprResult Expr(ParseAssignmentExpression()); if (ExpectAndConsume(tok::comma)) { SkipUntil(tok::r_paren, StopAtSemi); Expr = ExprError(); } TypeResult Ty = ParseTypeName(); if (Tok.isNot(tok::r_paren)) { Diag(Tok, diag::err_expected) << tok::r_paren; Expr = ExprError(); } if (Expr.isInvalid() || Ty.isInvalid()) Res = ExprError(); else Res = Actions.ActOnVAArg(StartLoc, Expr.get(), Ty.get(), ConsumeParen()); break; } case tok::kw___builtin_offsetof: { SourceLocation TypeLoc = Tok.getLocation(); TypeResult Ty = ParseTypeName(); if (Ty.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } if (ExpectAndConsume(tok::comma)) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } // We must have at least one identifier here. if (Tok.isNot(tok::identifier)) { Diag(Tok, diag::err_expected) << tok::identifier; SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } // Keep track of the various subcomponents we see. SmallVector Comps; Comps.push_back(Sema::OffsetOfComponent()); Comps.back().isBrackets = false; Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); Comps.back().LocStart = Comps.back().LocEnd = ConsumeToken(); // FIXME: This loop leaks the index expressions on error. while (1) { if (Tok.is(tok::period)) { // offsetof-member-designator: offsetof-member-designator '.' identifier Comps.push_back(Sema::OffsetOfComponent()); Comps.back().isBrackets = false; Comps.back().LocStart = ConsumeToken(); if (Tok.isNot(tok::identifier)) { Diag(Tok, diag::err_expected) << tok::identifier; SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); Comps.back().LocEnd = ConsumeToken(); } else if (Tok.is(tok::l_square)) { if (CheckProhibitedCXX11Attribute()) return ExprError(); // offsetof-member-designator: offsetof-member-design '[' expression ']' Comps.push_back(Sema::OffsetOfComponent()); Comps.back().isBrackets = true; BalancedDelimiterTracker ST(*this, tok::l_square); ST.consumeOpen(); Comps.back().LocStart = ST.getOpenLocation(); Res = ParseExpression(); if (Res.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return Res; } Comps.back().U.E = Res.get(); ST.consumeClose(); Comps.back().LocEnd = ST.getCloseLocation(); } else { if (Tok.isNot(tok::r_paren)) { PT.consumeClose(); Res = ExprError(); } else if (Ty.isInvalid()) { Res = ExprError(); } else { PT.consumeClose(); Res = Actions.ActOnBuiltinOffsetOf(getCurScope(), StartLoc, TypeLoc, Ty.get(), Comps, PT.getCloseLocation()); } break; } } break; } case tok::kw___builtin_choose_expr: { ExprResult Cond(ParseAssignmentExpression()); if (Cond.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return Cond; } if (ExpectAndConsume(tok::comma)) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } ExprResult Expr1(ParseAssignmentExpression()); if (Expr1.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return Expr1; } if (ExpectAndConsume(tok::comma)) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } ExprResult Expr2(ParseAssignmentExpression()); if (Expr2.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return Expr2; } if (Tok.isNot(tok::r_paren)) { Diag(Tok, diag::err_expected) << tok::r_paren; return ExprError(); } Res = Actions.ActOnChooseExpr(StartLoc, Cond.get(), Expr1.get(), Expr2.get(), ConsumeParen()); break; } case tok::kw___builtin_astype: { // The first argument is an expression to be converted, followed by a comma. ExprResult Expr(ParseAssignmentExpression()); if (Expr.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } if (ExpectAndConsume(tok::comma)) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } // Second argument is the type to bitcast to. TypeResult DestTy = ParseTypeName(); if (DestTy.isInvalid()) return ExprError(); // Attempt to consume the r-paren. if (Tok.isNot(tok::r_paren)) { Diag(Tok, diag::err_expected) << tok::r_paren; SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } Res = Actions.ActOnAsTypeExpr(Expr.get(), DestTy.get(), StartLoc, ConsumeParen()); break; } case tok::kw___builtin_convertvector: { // The first argument is an expression to be converted, followed by a comma. ExprResult Expr(ParseAssignmentExpression()); if (Expr.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } if (ExpectAndConsume(tok::comma)) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } // Second argument is the type to bitcast to. TypeResult DestTy = ParseTypeName(); if (DestTy.isInvalid()) return ExprError(); // Attempt to consume the r-paren. if (Tok.isNot(tok::r_paren)) { Diag(Tok, diag::err_expected) << tok::r_paren; SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } Res = Actions.ActOnConvertVectorExpr(Expr.get(), DestTy.get(), StartLoc, ConsumeParen()); break; } } if (Res.isInvalid()) return ExprError(); // These can be followed by postfix-expr pieces because they are // primary-expressions. return ParsePostfixExpressionSuffix(Res.get()); } /// ParseParenExpression - This parses the unit that starts with a '(' token, /// based on what is allowed by ExprType. The actual thing parsed is returned /// in ExprType. If stopIfCastExpr is true, it will only return the parsed type, /// not the parsed cast-expression. /// /// \verbatim /// primary-expression: [C99 6.5.1] /// '(' expression ')' /// [GNU] '(' compound-statement ')' (if !ParenExprOnly) /// postfix-expression: [C99 6.5.2] /// '(' type-name ')' '{' initializer-list '}' /// '(' type-name ')' '{' initializer-list ',' '}' /// cast-expression: [C99 6.5.4] /// '(' type-name ')' cast-expression /// [ARC] bridged-cast-expression /// [ARC] bridged-cast-expression: /// (__bridge type-name) cast-expression /// (__bridge_transfer type-name) cast-expression /// (__bridge_retained type-name) cast-expression /// fold-expression: [C++1z] /// '(' cast-expression fold-operator '...' ')' /// '(' '...' fold-operator cast-expression ')' /// '(' cast-expression fold-operator '...' /// fold-operator cast-expression ')' /// \endverbatim ExprResult Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr, bool isTypeCast, ParsedType &CastTy, SourceLocation &RParenLoc) { assert(Tok.is(tok::l_paren) && "Not a paren expr!"); ColonProtectionRAIIObject ColonProtection(*this, false); BalancedDelimiterTracker T(*this, tok::l_paren); if (T.consumeOpen()) return ExprError(); SourceLocation OpenLoc = T.getOpenLocation(); ExprResult Result(true); bool isAmbiguousTypeId; CastTy = nullptr; if (Tok.is(tok::code_completion)) { Actions.CodeCompleteOrdinaryName(getCurScope(), ExprType >= CompoundLiteral? Sema::PCC_ParenthesizedExpression : Sema::PCC_Expression); cutOffParsing(); return ExprError(); } // Diagnose use of bridge casts in non-arc mode. bool BridgeCast = (getLangOpts().ObjC2 && Tok.isOneOf(tok::kw___bridge, tok::kw___bridge_transfer, tok::kw___bridge_retained, tok::kw___bridge_retain)); if (BridgeCast && !getLangOpts().ObjCAutoRefCount) { if (!TryConsumeToken(tok::kw___bridge)) { StringRef BridgeCastName = Tok.getName(); SourceLocation BridgeKeywordLoc = ConsumeToken(); if (!PP.getSourceManager().isInSystemHeader(BridgeKeywordLoc)) Diag(BridgeKeywordLoc, diag::warn_arc_bridge_cast_nonarc) << BridgeCastName << FixItHint::CreateReplacement(BridgeKeywordLoc, ""); } BridgeCast = false; } // None of these cases should fall through with an invalid Result // unless they've already reported an error. if (ExprType >= CompoundStmt && Tok.is(tok::l_brace)) { Diag(Tok, diag::ext_gnu_statement_expr); if (!getCurScope()->getFnParent() && !getCurScope()->getBlockParent()) { Result = ExprError(Diag(OpenLoc, diag::err_stmtexpr_file_scope)); } else { // Find the nearest non-record decl context. Variables declared in a // statement expression behave as if they were declared in the enclosing // function, block, or other code construct. DeclContext *CodeDC = Actions.CurContext; while (CodeDC->isRecord() || isa(CodeDC)) { CodeDC = CodeDC->getParent(); assert(CodeDC && !CodeDC->isFileContext() && "statement expr not in code context"); } Sema::ContextRAII SavedContext(Actions, CodeDC, /*NewThisContext=*/false); Actions.ActOnStartStmtExpr(); StmtResult Stmt(ParseCompoundStatement(true)); ExprType = CompoundStmt; // If the substmt parsed correctly, build the AST node. if (!Stmt.isInvalid()) { Result = Actions.ActOnStmtExpr(OpenLoc, Stmt.get(), Tok.getLocation()); } else { Actions.ActOnStmtExprError(); } } } else if (ExprType >= CompoundLiteral && BridgeCast) { tok::TokenKind tokenKind = Tok.getKind(); SourceLocation BridgeKeywordLoc = ConsumeToken(); // Parse an Objective-C ARC ownership cast expression. ObjCBridgeCastKind Kind; if (tokenKind == tok::kw___bridge) Kind = OBC_Bridge; else if (tokenKind == tok::kw___bridge_transfer) Kind = OBC_BridgeTransfer; else if (tokenKind == tok::kw___bridge_retained) Kind = OBC_BridgeRetained; else { // As a hopefully temporary workaround, allow __bridge_retain as // a synonym for __bridge_retained, but only in system headers. assert(tokenKind == tok::kw___bridge_retain); Kind = OBC_BridgeRetained; if (!PP.getSourceManager().isInSystemHeader(BridgeKeywordLoc)) Diag(BridgeKeywordLoc, diag::err_arc_bridge_retain) << FixItHint::CreateReplacement(BridgeKeywordLoc, "__bridge_retained"); } TypeResult Ty = ParseTypeName(); T.consumeClose(); ColonProtection.restore(); RParenLoc = T.getCloseLocation(); ExprResult SubExpr = ParseCastExpression(/*isUnaryExpression=*/false); if (Ty.isInvalid() || SubExpr.isInvalid()) return ExprError(); return Actions.ActOnObjCBridgedCast(getCurScope(), OpenLoc, Kind, BridgeKeywordLoc, Ty.get(), RParenLoc, SubExpr.get()); } else if (ExprType >= CompoundLiteral && isTypeIdInParens(isAmbiguousTypeId)) { // Otherwise, this is a compound literal expression or cast expression. // In C++, if the type-id is ambiguous we disambiguate based on context. // If stopIfCastExpr is true the context is a typeof/sizeof/alignof // in which case we should treat it as type-id. // if stopIfCastExpr is false, we need to determine the context past the // parens, so we defer to ParseCXXAmbiguousParenExpression for that. if (isAmbiguousTypeId && !stopIfCastExpr) { ExprResult res = ParseCXXAmbiguousParenExpression(ExprType, CastTy, T, ColonProtection); RParenLoc = T.getCloseLocation(); return res; } // Parse the type declarator. DeclSpec DS(AttrFactory); ParseSpecifierQualifierList(DS); Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext); ParseDeclarator(DeclaratorInfo); // If our type is followed by an identifier and either ':' or ']', then // this is probably an Objective-C message send where the leading '[' is // missing. Recover as if that were the case. if (!DeclaratorInfo.isInvalidType() && Tok.is(tok::identifier) && !InMessageExpression && getLangOpts().ObjC1 && (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) { TypeResult Ty; { InMessageExpressionRAIIObject InMessage(*this, false); Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); } Result = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), Ty.get(), nullptr); } else { // Match the ')'. T.consumeClose(); ColonProtection.restore(); RParenLoc = T.getCloseLocation(); if (Tok.is(tok::l_brace)) { ExprType = CompoundLiteral; TypeResult Ty; { InMessageExpressionRAIIObject InMessage(*this, false); Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); } return ParseCompoundLiteralExpression(Ty.get(), OpenLoc, RParenLoc); } if (Tok.is(tok::l_paren)) { // This could be OpenCL vector Literals if (getLangOpts().OpenCL) { TypeResult Ty; { InMessageExpressionRAIIObject InMessage(*this, false); Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); } if(Ty.isInvalid()) { return ExprError(); } QualType QT = Ty.get().get().getCanonicalType(); if (QT->isVectorType()) { // We parsed '(' vector-type-name ')' followed by '(' // Parse the cast-expression that follows it next. // isVectorLiteral = true will make sure we don't parse any // Postfix expression yet Result = ParseCastExpression(/*isUnaryExpression=*/false, /*isAddressOfOperand=*/false, /*isTypeCast=*/IsTypeCast, /*isVectorLiteral=*/true); if (!Result.isInvalid()) { Result = Actions.ActOnCastExpr(getCurScope(), OpenLoc, DeclaratorInfo, CastTy, RParenLoc, Result.get()); } // After we performed the cast we can check for postfix-expr pieces. if (!Result.isInvalid()) { Result = ParsePostfixExpressionSuffix(Result); } return Result; } } } if (ExprType == CastExpr) { // We parsed '(' type-name ')' and the thing after it wasn't a '{'. if (DeclaratorInfo.isInvalidType()) return ExprError(); // Note that this doesn't parse the subsequent cast-expression, it just // returns the parsed type to the callee. if (stopIfCastExpr) { TypeResult Ty; { InMessageExpressionRAIIObject InMessage(*this, false); Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); } CastTy = Ty.get(); return ExprResult(); } // Reject the cast of super idiom in ObjC. if (Tok.is(tok::identifier) && getLangOpts().ObjC1 && Tok.getIdentifierInfo() == Ident_super && getCurScope()->isInObjcMethodScope() && GetLookAheadToken(1).isNot(tok::period)) { Diag(Tok.getLocation(), diag::err_illegal_super_cast) << SourceRange(OpenLoc, RParenLoc); return ExprError(); } // Parse the cast-expression that follows it next. // TODO: For cast expression with CastTy. Result = ParseCastExpression(/*isUnaryExpression=*/false, /*isAddressOfOperand=*/false, /*isTypeCast=*/IsTypeCast); if (!Result.isInvalid()) { Result = Actions.ActOnCastExpr(getCurScope(), OpenLoc, DeclaratorInfo, CastTy, RParenLoc, Result.get()); } return Result; } Diag(Tok, diag::err_expected_lbrace_in_compound_literal); return ExprError(); } } else if (Tok.is(tok::ellipsis) && isFoldOperator(NextToken().getKind())) { return ParseFoldExpression(ExprResult(), T); } else if (isTypeCast) { // Parse the expression-list. InMessageExpressionRAIIObject InMessage(*this, false); ExprVector ArgExprs; CommaLocsTy CommaLocs; if (!ParseSimpleExpressionList(ArgExprs, CommaLocs)) { // FIXME: If we ever support comma expressions as operands to // fold-expressions, we'll need to allow multiple ArgExprs here. if (ArgExprs.size() == 1 && isFoldOperator(Tok.getKind()) && NextToken().is(tok::ellipsis)) return ParseFoldExpression(ArgExprs[0], T); ExprType = SimpleExpr; Result = Actions.ActOnParenListExpr(OpenLoc, Tok.getLocation(), ArgExprs); } } else { InMessageExpressionRAIIObject InMessage(*this, false); Result = ParseExpression(MaybeTypeCast); if (!getLangOpts().CPlusPlus && MaybeTypeCast && Result.isUsable()) { // Correct typos in non-C++ code earlier so that implicit-cast-like // expressions are parsed correctly. Result = Actions.CorrectDelayedTyposInExpr(Result); } ExprType = SimpleExpr; if (isFoldOperator(Tok.getKind()) && NextToken().is(tok::ellipsis)) return ParseFoldExpression(Result, T); // Don't build a paren expression unless we actually match a ')'. if (!Result.isInvalid() && Tok.is(tok::r_paren)) Result = Actions.ActOnParenExpr(OpenLoc, Tok.getLocation(), Result.get()); } // Match the ')'. if (Result.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } T.consumeClose(); RParenLoc = T.getCloseLocation(); return Result; } /// ParseCompoundLiteralExpression - We have parsed the parenthesized type-name /// and we are at the left brace. /// /// \verbatim /// postfix-expression: [C99 6.5.2] /// '(' type-name ')' '{' initializer-list '}' /// '(' type-name ')' '{' initializer-list ',' '}' /// \endverbatim ExprResult Parser::ParseCompoundLiteralExpression(ParsedType Ty, SourceLocation LParenLoc, SourceLocation RParenLoc) { assert(Tok.is(tok::l_brace) && "Not a compound literal!"); if (!getLangOpts().C99) // Compound literals don't exist in C90. Diag(LParenLoc, diag::ext_c99_compound_literal); ExprResult Result = ParseInitializer(); if (!Result.isInvalid() && Ty) return Actions.ActOnCompoundLiteral(LParenLoc, Ty, RParenLoc, Result.get()); return Result; } /// ParseStringLiteralExpression - This handles the various token types that /// form string literals, and also handles string concatenation [C99 5.1.1.2, /// translation phase #6]. /// /// \verbatim /// primary-expression: [C99 6.5.1] /// string-literal /// \verbatim ExprResult Parser::ParseStringLiteralExpression(bool AllowUserDefinedLiteral) { assert(isTokenStringLiteral() && "Not a string literal!"); // String concat. Note that keywords like __func__ and __FUNCTION__ are not // considered to be strings for concatenation purposes. SmallVector StringToks; do { StringToks.push_back(Tok); ConsumeStringToken(); } while (isTokenStringLiteral()); // Pass the set of string tokens, ready for concatenation, to the actions. return Actions.ActOnStringLiteral(StringToks, AllowUserDefinedLiteral ? getCurScope() : nullptr); } /// ParseGenericSelectionExpression - Parse a C11 generic-selection /// [C11 6.5.1.1]. /// /// \verbatim /// generic-selection: /// _Generic ( assignment-expression , generic-assoc-list ) /// generic-assoc-list: /// generic-association /// generic-assoc-list , generic-association /// generic-association: /// type-name : assignment-expression /// default : assignment-expression /// \endverbatim ExprResult Parser::ParseGenericSelectionExpression() { assert(Tok.is(tok::kw__Generic) && "_Generic keyword expected"); SourceLocation KeyLoc = ConsumeToken(); if (!getLangOpts().C11) Diag(KeyLoc, diag::ext_c11_generic_selection); BalancedDelimiterTracker T(*this, tok::l_paren); if (T.expectAndConsume()) return ExprError(); ExprResult ControllingExpr; { // C11 6.5.1.1p3 "The controlling expression of a generic selection is // not evaluated." EnterExpressionEvaluationContext Unevaluated( Actions, Sema::ExpressionEvaluationContext::Unevaluated); ControllingExpr = Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression()); if (ControllingExpr.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } } if (ExpectAndConsume(tok::comma)) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } SourceLocation DefaultLoc; TypeVector Types; ExprVector Exprs; do { ParsedType Ty; if (Tok.is(tok::kw_default)) { // C11 6.5.1.1p2 "A generic selection shall have no more than one default // generic association." if (!DefaultLoc.isInvalid()) { Diag(Tok, diag::err_duplicate_default_assoc); Diag(DefaultLoc, diag::note_previous_default_assoc); SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } DefaultLoc = ConsumeToken(); Ty = nullptr; } else { ColonProtectionRAIIObject X(*this); TypeResult TR = ParseTypeName(); if (TR.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } Ty = TR.get(); } Types.push_back(Ty); if (ExpectAndConsume(tok::colon)) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } // FIXME: These expressions should be parsed in a potentially potentially // evaluated context. ExprResult ER( Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression())); if (ER.isInvalid()) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } Exprs.push_back(ER.get()); } while (TryConsumeToken(tok::comma)); T.consumeClose(); if (T.getCloseLocation().isInvalid()) return ExprError(); return Actions.ActOnGenericSelectionExpr(KeyLoc, DefaultLoc, T.getCloseLocation(), ControllingExpr.get(), Types, Exprs); } /// Parse A C++1z fold-expression after the opening paren and optional /// left-hand-side expression. /// /// \verbatim /// fold-expression: /// ( cast-expression fold-operator ... ) /// ( ... fold-operator cast-expression ) /// ( cast-expression fold-operator ... fold-operator cast-expression ) ExprResult Parser::ParseFoldExpression(ExprResult LHS, BalancedDelimiterTracker &T) { if (LHS.isInvalid()) { T.skipToEnd(); return true; } tok::TokenKind Kind = tok::unknown; SourceLocation FirstOpLoc; if (LHS.isUsable()) { Kind = Tok.getKind(); assert(isFoldOperator(Kind) && "missing fold-operator"); FirstOpLoc = ConsumeToken(); } assert(Tok.is(tok::ellipsis) && "not a fold-expression"); SourceLocation EllipsisLoc = ConsumeToken(); ExprResult RHS; if (Tok.isNot(tok::r_paren)) { if (!isFoldOperator(Tok.getKind())) return Diag(Tok.getLocation(), diag::err_expected_fold_operator); if (Kind != tok::unknown && Tok.getKind() != Kind) Diag(Tok.getLocation(), diag::err_fold_operator_mismatch) << SourceRange(FirstOpLoc); Kind = Tok.getKind(); ConsumeToken(); RHS = ParseExpression(); if (RHS.isInvalid()) { T.skipToEnd(); return true; } } Diag(EllipsisLoc, getLangOpts().CPlusPlus17 ? diag::warn_cxx14_compat_fold_expression : diag::ext_fold_expression); T.consumeClose(); return Actions.ActOnCXXFoldExpr(T.getOpenLocation(), LHS.get(), Kind, EllipsisLoc, RHS.get(), T.getCloseLocation()); } /// ParseExpressionList - Used for C/C++ (argument-)expression-list. /// /// \verbatim /// argument-expression-list: /// assignment-expression /// argument-expression-list , assignment-expression /// /// [C++] expression-list: /// [C++] assignment-expression /// [C++] expression-list , assignment-expression /// /// [C++0x] expression-list: /// [C++0x] initializer-list /// /// [C++0x] initializer-list /// [C++0x] initializer-clause ...[opt] /// [C++0x] initializer-list , initializer-clause ...[opt] /// /// [C++0x] initializer-clause: /// [C++0x] assignment-expression /// [C++0x] braced-init-list /// \endverbatim bool Parser::ParseExpressionList(SmallVectorImpl &Exprs, SmallVectorImpl &CommaLocs, llvm::function_ref Completer) { bool SawError = false; while (1) { if (Tok.is(tok::code_completion)) { if (Completer) Completer(); else Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); cutOffParsing(); return true; } ExprResult Expr; if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) { Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); Expr = ParseBraceInitializer(); } else Expr = ParseAssignmentExpression(); if (Tok.is(tok::ellipsis)) Expr = Actions.ActOnPackExpansion(Expr.get(), ConsumeToken()); if (Expr.isInvalid()) { SkipUntil(tok::comma, tok::r_paren, StopBeforeMatch); SawError = true; } else { Exprs.push_back(Expr.get()); } if (Tok.isNot(tok::comma)) break; // Move to the next argument, remember where the comma was. Token Comma = Tok; CommaLocs.push_back(ConsumeToken()); checkPotentialAngleBracketDelimiter(Comma); } if (SawError) { // Ensure typos get diagnosed when errors were encountered while parsing the // expression list. for (auto &E : Exprs) { ExprResult Expr = Actions.CorrectDelayedTyposInExpr(E); if (Expr.isUsable()) E = Expr.get(); } } return SawError; } /// ParseSimpleExpressionList - A simple comma-separated list of expressions, /// used for misc language extensions. /// /// \verbatim /// simple-expression-list: /// assignment-expression /// simple-expression-list , assignment-expression /// \endverbatim bool Parser::ParseSimpleExpressionList(SmallVectorImpl &Exprs, SmallVectorImpl &CommaLocs) { while (1) { ExprResult Expr = ParseAssignmentExpression(); if (Expr.isInvalid()) return true; Exprs.push_back(Expr.get()); if (Tok.isNot(tok::comma)) return false; // Move to the next argument, remember where the comma was. Token Comma = Tok; CommaLocs.push_back(ConsumeToken()); checkPotentialAngleBracketDelimiter(Comma); } } /// ParseBlockId - Parse a block-id, which roughly looks like int (int x). /// /// \verbatim /// [clang] block-id: /// [clang] specifier-qualifier-list block-declarator /// \endverbatim void Parser::ParseBlockId(SourceLocation CaretLoc) { if (Tok.is(tok::code_completion)) { Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Type); return cutOffParsing(); } // Parse the specifier-qualifier-list piece. DeclSpec DS(AttrFactory); ParseSpecifierQualifierList(DS); // Parse the block-declarator. Declarator DeclaratorInfo(DS, DeclaratorContext::BlockLiteralContext); DeclaratorInfo.setFunctionDefinitionKind(FDK_Definition); ParseDeclarator(DeclaratorInfo); MaybeParseGNUAttributes(DeclaratorInfo); // Inform sema that we are starting a block. Actions.ActOnBlockArguments(CaretLoc, DeclaratorInfo, getCurScope()); } /// ParseBlockLiteralExpression - Parse a block literal, which roughly looks /// like ^(int x){ return x+1; } /// /// \verbatim /// block-literal: /// [clang] '^' block-args[opt] compound-statement /// [clang] '^' block-id compound-statement /// [clang] block-args: /// [clang] '(' parameter-list ')' /// \endverbatim ExprResult Parser::ParseBlockLiteralExpression() { assert(Tok.is(tok::caret) && "block literal starts with ^"); SourceLocation CaretLoc = ConsumeToken(); PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), CaretLoc, "block literal parsing"); // Enter a scope to hold everything within the block. This includes the // argument decls, decls within the compound expression, etc. This also // allows determining whether a variable reference inside the block is // within or outside of the block. ParseScope BlockScope(this, Scope::BlockScope | Scope::FnScope | Scope::CompoundStmtScope | Scope::DeclScope); // Inform sema that we are starting a block. Actions.ActOnBlockStart(CaretLoc, getCurScope()); // Parse the return type if present. DeclSpec DS(AttrFactory); Declarator ParamInfo(DS, DeclaratorContext::BlockLiteralContext); ParamInfo.setFunctionDefinitionKind(FDK_Definition); // FIXME: Since the return type isn't actually parsed, it can't be used to // fill ParamInfo with an initial valid range, so do it manually. ParamInfo.SetSourceRange(SourceRange(Tok.getLocation(), Tok.getLocation())); // If this block has arguments, parse them. There is no ambiguity here with // the expression case, because the expression case requires a parameter list. if (Tok.is(tok::l_paren)) { ParseParenDeclarator(ParamInfo); // Parse the pieces after the identifier as if we had "int(...)". // SetIdentifier sets the source range end, but in this case we're past // that location. SourceLocation Tmp = ParamInfo.getSourceRange().getEnd(); ParamInfo.SetIdentifier(nullptr, CaretLoc); ParamInfo.SetRangeEnd(Tmp); if (ParamInfo.isInvalidType()) { // If there was an error parsing the arguments, they may have // tried to use ^(x+y) which requires an argument list. Just // skip the whole block literal. Actions.ActOnBlockError(CaretLoc, getCurScope()); return ExprError(); } MaybeParseGNUAttributes(ParamInfo); // Inform sema that we are starting a block. Actions.ActOnBlockArguments(CaretLoc, ParamInfo, getCurScope()); } else if (!Tok.is(tok::l_brace)) { ParseBlockId(CaretLoc); } else { // Otherwise, pretend we saw (void). SourceLocation NoLoc; ParamInfo.AddTypeInfo( DeclaratorChunk::getFunction(/*HasProto=*/true, /*IsAmbiguous=*/false, /*RParenLoc=*/NoLoc, /*ArgInfo=*/nullptr, /*NumArgs=*/0, /*EllipsisLoc=*/NoLoc, /*RParenLoc=*/NoLoc, /*TypeQuals=*/0, /*RefQualifierIsLvalueRef=*/true, /*RefQualifierLoc=*/NoLoc, /*ConstQualifierLoc=*/NoLoc, /*VolatileQualifierLoc=*/NoLoc, /*RestrictQualifierLoc=*/NoLoc, /*MutableLoc=*/NoLoc, EST_None, /*ESpecRange=*/SourceRange(), /*Exceptions=*/nullptr, /*ExceptionRanges=*/nullptr, /*NumExceptions=*/0, /*NoexceptExpr=*/nullptr, /*ExceptionSpecTokens=*/nullptr, /*DeclsInPrototype=*/None, CaretLoc, CaretLoc, ParamInfo), CaretLoc); MaybeParseGNUAttributes(ParamInfo); // Inform sema that we are starting a block. Actions.ActOnBlockArguments(CaretLoc, ParamInfo, getCurScope()); } ExprResult Result(true); if (!Tok.is(tok::l_brace)) { // Saw something like: ^expr Diag(Tok, diag::err_expected_expression); Actions.ActOnBlockError(CaretLoc, getCurScope()); return ExprError(); } StmtResult Stmt(ParseCompoundStatementBody()); BlockScope.Exit(); if (!Stmt.isInvalid()) Result = Actions.ActOnBlockStmtExpr(CaretLoc, Stmt.get(), getCurScope()); else Actions.ActOnBlockError(CaretLoc, getCurScope()); return Result; } /// ParseObjCBoolLiteral - This handles the objective-c Boolean literals. /// /// '__objc_yes' /// '__objc_no' ExprResult Parser::ParseObjCBoolLiteral() { tok::TokenKind Kind = Tok.getKind(); return Actions.ActOnObjCBoolLiteral(ConsumeToken(), Kind); } /// Validate availability spec list, emitting diagnostics if necessary. Returns /// true if invalid. static bool CheckAvailabilitySpecList(Parser &P, ArrayRef AvailSpecs) { llvm::SmallSet Platforms; bool HasOtherPlatformSpec = false; bool Valid = true; for (const auto &Spec : AvailSpecs) { if (Spec.isOtherPlatformSpec()) { if (HasOtherPlatformSpec) { P.Diag(Spec.getBeginLoc(), diag::err_availability_query_repeated_star); Valid = false; } HasOtherPlatformSpec = true; continue; } bool Inserted = Platforms.insert(Spec.getPlatform()).second; if (!Inserted) { // Rule out multiple version specs referring to the same platform. // For example, we emit an error for: // @available(macos 10.10, macos 10.11, *) StringRef Platform = Spec.getPlatform(); P.Diag(Spec.getBeginLoc(), diag::err_availability_query_repeated_platform) << Spec.getEndLoc() << Platform; Valid = false; } } if (!HasOtherPlatformSpec) { SourceLocation InsertWildcardLoc = AvailSpecs.back().getEndLoc(); P.Diag(InsertWildcardLoc, diag::err_availability_query_wildcard_required) << FixItHint::CreateInsertion(InsertWildcardLoc, ", *"); return true; } return !Valid; } /// Parse availability query specification. /// /// availability-spec: /// '*' /// identifier version-tuple Optional Parser::ParseAvailabilitySpec() { if (Tok.is(tok::star)) { return AvailabilitySpec(ConsumeToken()); } else { // Parse the platform name. if (Tok.is(tok::code_completion)) { Actions.CodeCompleteAvailabilityPlatformName(); cutOffParsing(); return None; } if (Tok.isNot(tok::identifier)) { Diag(Tok, diag::err_avail_query_expected_platform_name); return None; } IdentifierLoc *PlatformIdentifier = ParseIdentifierLoc(); SourceRange VersionRange; VersionTuple Version = ParseVersionTuple(VersionRange); if (Version.empty()) return None; StringRef GivenPlatform = PlatformIdentifier->Ident->getName(); StringRef Platform = AvailabilityAttr::canonicalizePlatformName(GivenPlatform); if (AvailabilityAttr::getPrettyPlatformName(Platform).empty()) { Diag(PlatformIdentifier->Loc, diag::err_avail_query_unrecognized_platform_name) << GivenPlatform; return None; } return AvailabilitySpec(Version, Platform, PlatformIdentifier->Loc, VersionRange.getEnd()); } } ExprResult Parser::ParseAvailabilityCheckExpr(SourceLocation BeginLoc) { assert(Tok.is(tok::kw___builtin_available) || Tok.isObjCAtKeyword(tok::objc_available)); // Eat the available or __builtin_available. ConsumeToken(); BalancedDelimiterTracker Parens(*this, tok::l_paren); if (Parens.expectAndConsume()) return ExprError(); SmallVector AvailSpecs; bool HasError = false; while (true) { Optional Spec = ParseAvailabilitySpec(); if (!Spec) HasError = true; else AvailSpecs.push_back(*Spec); if (!TryConsumeToken(tok::comma)) break; } if (HasError) { SkipUntil(tok::r_paren, StopAtSemi); return ExprError(); } CheckAvailabilitySpecList(*this, AvailSpecs); if (Parens.consumeClose()) return ExprError(); return Actions.ActOnObjCAvailabilityCheckExpr(AvailSpecs, BeginLoc, Parens.getCloseLocation()); }