ParseExpr.cpp revision 6bcf27bb9a4b5c3f79cb44c0e4654a6d7619ad89
1//===--- ParseExpr.cpp - Expression Parsing -------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9/// 10/// \file 11/// \brief Provides the Expression parsing implementation. 12/// 13/// Expressions in C99 basically consist of a bunch of binary operators with 14/// unary operators and other random stuff at the leaves. 15/// 16/// In the C99 grammar, these unary operators bind tightest and are represented 17/// as the 'cast-expression' production. Everything else is either a binary 18/// operator (e.g. '/') or a ternary operator ("?:"). The unary leaves are 19/// handled by ParseCastExpression, the higher level pieces are handled by 20/// ParseBinaryExpression. 21/// 22//===----------------------------------------------------------------------===// 23 24#include "clang/Parse/Parser.h" 25#include "RAIIObjectsForParser.h" 26#include "clang/AST/ASTContext.h" 27#include "clang/Basic/PrettyStackTrace.h" 28#include "clang/Sema/DeclSpec.h" 29#include "clang/Sema/ParsedTemplate.h" 30#include "clang/Sema/Scope.h" 31#include "clang/Sema/TypoCorrection.h" 32#include "llvm/ADT/SmallString.h" 33#include "llvm/ADT/SmallVector.h" 34using namespace clang; 35 36/// \brief Simple precedence-based parser for binary/ternary operators. 37/// 38/// Note: we diverge from the C99 grammar when parsing the assignment-expression 39/// production. C99 specifies that the LHS of an assignment operator should be 40/// parsed as a unary-expression, but consistency dictates that it be a 41/// conditional-expession. In practice, the important thing here is that the 42/// LHS of an assignment has to be an l-value, which productions between 43/// unary-expression and conditional-expression don't produce. Because we want 44/// consistency, we parse the LHS as a conditional-expression, then check for 45/// l-value-ness in semantic analysis stages. 46/// 47/// \verbatim 48/// pm-expression: [C++ 5.5] 49/// cast-expression 50/// pm-expression '.*' cast-expression 51/// pm-expression '->*' cast-expression 52/// 53/// multiplicative-expression: [C99 6.5.5] 54/// Note: in C++, apply pm-expression instead of cast-expression 55/// cast-expression 56/// multiplicative-expression '*' cast-expression 57/// multiplicative-expression '/' cast-expression 58/// multiplicative-expression '%' cast-expression 59/// 60/// additive-expression: [C99 6.5.6] 61/// multiplicative-expression 62/// additive-expression '+' multiplicative-expression 63/// additive-expression '-' multiplicative-expression 64/// 65/// shift-expression: [C99 6.5.7] 66/// additive-expression 67/// shift-expression '<<' additive-expression 68/// shift-expression '>>' additive-expression 69/// 70/// relational-expression: [C99 6.5.8] 71/// shift-expression 72/// relational-expression '<' shift-expression 73/// relational-expression '>' shift-expression 74/// relational-expression '<=' shift-expression 75/// relational-expression '>=' shift-expression 76/// 77/// equality-expression: [C99 6.5.9] 78/// relational-expression 79/// equality-expression '==' relational-expression 80/// equality-expression '!=' relational-expression 81/// 82/// AND-expression: [C99 6.5.10] 83/// equality-expression 84/// AND-expression '&' equality-expression 85/// 86/// exclusive-OR-expression: [C99 6.5.11] 87/// AND-expression 88/// exclusive-OR-expression '^' AND-expression 89/// 90/// inclusive-OR-expression: [C99 6.5.12] 91/// exclusive-OR-expression 92/// inclusive-OR-expression '|' exclusive-OR-expression 93/// 94/// logical-AND-expression: [C99 6.5.13] 95/// inclusive-OR-expression 96/// logical-AND-expression '&&' inclusive-OR-expression 97/// 98/// logical-OR-expression: [C99 6.5.14] 99/// logical-AND-expression 100/// logical-OR-expression '||' logical-AND-expression 101/// 102/// conditional-expression: [C99 6.5.15] 103/// logical-OR-expression 104/// logical-OR-expression '?' expression ':' conditional-expression 105/// [GNU] logical-OR-expression '?' ':' conditional-expression 106/// [C++] the third operand is an assignment-expression 107/// 108/// assignment-expression: [C99 6.5.16] 109/// conditional-expression 110/// unary-expression assignment-operator assignment-expression 111/// [C++] throw-expression [C++ 15] 112/// 113/// assignment-operator: one of 114/// = *= /= %= += -= <<= >>= &= ^= |= 115/// 116/// expression: [C99 6.5.17] 117/// assignment-expression ...[opt] 118/// expression ',' assignment-expression ...[opt] 119/// \endverbatim 120ExprResult Parser::ParseExpression(TypeCastState isTypeCast) { 121 ExprResult LHS(ParseAssignmentExpression(isTypeCast)); 122 return ParseRHSOfBinaryExpression(LHS, prec::Comma); 123} 124 125/// This routine is called when the '@' is seen and consumed. 126/// Current token is an Identifier and is not a 'try'. This 127/// routine is necessary to disambiguate \@try-statement from, 128/// for example, \@encode-expression. 129/// 130ExprResult 131Parser::ParseExpressionWithLeadingAt(SourceLocation AtLoc) { 132 ExprResult LHS(ParseObjCAtExpression(AtLoc)); 133 return ParseRHSOfBinaryExpression(LHS, prec::Comma); 134} 135 136/// This routine is called when a leading '__extension__' is seen and 137/// consumed. This is necessary because the token gets consumed in the 138/// process of disambiguating between an expression and a declaration. 139ExprResult 140Parser::ParseExpressionWithLeadingExtension(SourceLocation ExtLoc) { 141 ExprResult LHS(true); 142 { 143 // Silence extension warnings in the sub-expression 144 ExtensionRAIIObject O(Diags); 145 146 LHS = ParseCastExpression(false); 147 } 148 149 if (!LHS.isInvalid()) 150 LHS = Actions.ActOnUnaryOp(getCurScope(), ExtLoc, tok::kw___extension__, 151 LHS.take()); 152 153 return ParseRHSOfBinaryExpression(LHS, prec::Comma); 154} 155 156/// \brief Parse an expr that doesn't include (top-level) commas. 157ExprResult Parser::ParseAssignmentExpression(TypeCastState isTypeCast) { 158 if (Tok.is(tok::code_completion)) { 159 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); 160 cutOffParsing(); 161 return ExprError(); 162 } 163 164 if (Tok.is(tok::kw_throw)) 165 return ParseThrowExpression(); 166 167 ExprResult LHS = ParseCastExpression(/*isUnaryExpression=*/false, 168 /*isAddressOfOperand=*/false, 169 isTypeCast); 170 return ParseRHSOfBinaryExpression(LHS, prec::Assignment); 171} 172 173/// \brief Parse an assignment expression where part of an Objective-C message 174/// send has already been parsed. 175/// 176/// In this case \p LBracLoc indicates the location of the '[' of the message 177/// send, and either \p ReceiverName or \p ReceiverExpr is non-null indicating 178/// the receiver of the message. 179/// 180/// Since this handles full assignment-expression's, it handles postfix 181/// expressions and other binary operators for these expressions as well. 182ExprResult 183Parser::ParseAssignmentExprWithObjCMessageExprStart(SourceLocation LBracLoc, 184 SourceLocation SuperLoc, 185 ParsedType ReceiverType, 186 Expr *ReceiverExpr) { 187 ExprResult R 188 = ParseObjCMessageExpressionBody(LBracLoc, SuperLoc, 189 ReceiverType, ReceiverExpr); 190 R = ParsePostfixExpressionSuffix(R); 191 return ParseRHSOfBinaryExpression(R, prec::Assignment); 192} 193 194 195ExprResult Parser::ParseConstantExpression(TypeCastState isTypeCast) { 196 // C++03 [basic.def.odr]p2: 197 // An expression is potentially evaluated unless it appears where an 198 // integral constant expression is required (see 5.19) [...]. 199 // C++98 and C++11 have no such rule, but this is only a defect in C++98. 200 EnterExpressionEvaluationContext Unevaluated(Actions, 201 Sema::ConstantEvaluated); 202 203 ExprResult LHS(ParseCastExpression(false, false, isTypeCast)); 204 ExprResult Res(ParseRHSOfBinaryExpression(LHS, prec::Conditional)); 205 return Actions.ActOnConstantExpression(Res); 206} 207 208bool Parser::isNotExpressionStart() { 209 tok::TokenKind K = Tok.getKind(); 210 if (K == tok::l_brace || K == tok::r_brace || 211 K == tok::kw_for || K == tok::kw_while || 212 K == tok::kw_if || K == tok::kw_else || 213 K == tok::kw_goto || K == tok::kw_try) 214 return true; 215 // If this is a decl-specifier, we can't be at the start of an expression. 216 return isKnownToBeDeclarationSpecifier(); 217} 218 219/// \brief Parse a binary expression that starts with \p LHS and has a 220/// precedence of at least \p MinPrec. 221ExprResult 222Parser::ParseRHSOfBinaryExpression(ExprResult LHS, prec::Level MinPrec) { 223 prec::Level NextTokPrec = getBinOpPrecedence(Tok.getKind(), 224 GreaterThanIsOperator, 225 getLangOpts().CPlusPlus11); 226 SourceLocation ColonLoc; 227 228 while (1) { 229 // If this token has a lower precedence than we are allowed to parse (e.g. 230 // because we are called recursively, or because the token is not a binop), 231 // then we are done! 232 if (NextTokPrec < MinPrec) 233 return LHS; 234 235 // Consume the operator, saving the operator token for error reporting. 236 Token OpToken = Tok; 237 ConsumeToken(); 238 239 // Bail out when encountering a comma followed by a token which can't 240 // possibly be the start of an expression. For instance: 241 // int f() { return 1, } 242 // We can't do this before consuming the comma, because 243 // isNotExpressionStart() looks at the token stream. 244 if (OpToken.is(tok::comma) && isNotExpressionStart()) { 245 PP.EnterToken(Tok); 246 Tok = OpToken; 247 return LHS; 248 } 249 250 // Special case handling for the ternary operator. 251 ExprResult TernaryMiddle(true); 252 if (NextTokPrec == prec::Conditional) { 253 if (Tok.isNot(tok::colon)) { 254 // Don't parse FOO:BAR as if it were a typo for FOO::BAR. 255 ColonProtectionRAIIObject X(*this); 256 257 // Handle this production specially: 258 // logical-OR-expression '?' expression ':' conditional-expression 259 // In particular, the RHS of the '?' is 'expression', not 260 // 'logical-OR-expression' as we might expect. 261 TernaryMiddle = ParseExpression(); 262 if (TernaryMiddle.isInvalid()) { 263 LHS = ExprError(); 264 TernaryMiddle = nullptr; 265 } 266 } else { 267 // Special case handling of "X ? Y : Z" where Y is empty: 268 // logical-OR-expression '?' ':' conditional-expression [GNU] 269 TernaryMiddle = nullptr; 270 Diag(Tok, diag::ext_gnu_conditional_expr); 271 } 272 273 if (!TryConsumeToken(tok::colon, ColonLoc)) { 274 // Otherwise, we're missing a ':'. Assume that this was a typo that 275 // the user forgot. If we're not in a macro expansion, we can suggest 276 // a fixit hint. If there were two spaces before the current token, 277 // suggest inserting the colon in between them, otherwise insert ": ". 278 SourceLocation FILoc = Tok.getLocation(); 279 const char *FIText = ": "; 280 const SourceManager &SM = PP.getSourceManager(); 281 if (FILoc.isFileID() || PP.isAtStartOfMacroExpansion(FILoc, &FILoc)) { 282 assert(FILoc.isFileID()); 283 bool IsInvalid = false; 284 const char *SourcePtr = 285 SM.getCharacterData(FILoc.getLocWithOffset(-1), &IsInvalid); 286 if (!IsInvalid && *SourcePtr == ' ') { 287 SourcePtr = 288 SM.getCharacterData(FILoc.getLocWithOffset(-2), &IsInvalid); 289 if (!IsInvalid && *SourcePtr == ' ') { 290 FILoc = FILoc.getLocWithOffset(-1); 291 FIText = ":"; 292 } 293 } 294 } 295 296 Diag(Tok, diag::err_expected) 297 << tok::colon << FixItHint::CreateInsertion(FILoc, FIText); 298 Diag(OpToken, diag::note_matching) << tok::question; 299 ColonLoc = Tok.getLocation(); 300 } 301 } 302 303 // Code completion for the right-hand side of an assignment expression 304 // goes through a special hook that takes the left-hand side into account. 305 if (Tok.is(tok::code_completion) && NextTokPrec == prec::Assignment) { 306 Actions.CodeCompleteAssignmentRHS(getCurScope(), LHS.get()); 307 cutOffParsing(); 308 return ExprError(); 309 } 310 311 // Parse another leaf here for the RHS of the operator. 312 // ParseCastExpression works here because all RHS expressions in C have it 313 // as a prefix, at least. However, in C++, an assignment-expression could 314 // be a throw-expression, which is not a valid cast-expression. 315 // Therefore we need some special-casing here. 316 // Also note that the third operand of the conditional operator is 317 // an assignment-expression in C++, and in C++11, we can have a 318 // braced-init-list on the RHS of an assignment. For better diagnostics, 319 // parse as if we were allowed braced-init-lists everywhere, and check that 320 // they only appear on the RHS of assignments later. 321 ExprResult RHS; 322 bool RHSIsInitList = false; 323 if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) { 324 RHS = ParseBraceInitializer(); 325 RHSIsInitList = true; 326 } else if (getLangOpts().CPlusPlus && NextTokPrec <= prec::Conditional) 327 RHS = ParseAssignmentExpression(); 328 else 329 RHS = ParseCastExpression(false); 330 331 if (RHS.isInvalid()) 332 LHS = ExprError(); 333 334 // Remember the precedence of this operator and get the precedence of the 335 // operator immediately to the right of the RHS. 336 prec::Level ThisPrec = NextTokPrec; 337 NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator, 338 getLangOpts().CPlusPlus11); 339 340 // Assignment and conditional expressions are right-associative. 341 bool isRightAssoc = ThisPrec == prec::Conditional || 342 ThisPrec == prec::Assignment; 343 344 // Get the precedence of the operator to the right of the RHS. If it binds 345 // more tightly with RHS than we do, evaluate it completely first. 346 if (ThisPrec < NextTokPrec || 347 (ThisPrec == NextTokPrec && isRightAssoc)) { 348 if (!RHS.isInvalid() && RHSIsInitList) { 349 Diag(Tok, diag::err_init_list_bin_op) 350 << /*LHS*/0 << PP.getSpelling(Tok) << Actions.getExprRange(RHS.get()); 351 RHS = ExprError(); 352 } 353 // If this is left-associative, only parse things on the RHS that bind 354 // more tightly than the current operator. If it is left-associative, it 355 // is okay, to bind exactly as tightly. For example, compile A=B=C=D as 356 // A=(B=(C=D)), where each paren is a level of recursion here. 357 // The function takes ownership of the RHS. 358 RHS = ParseRHSOfBinaryExpression(RHS, 359 static_cast<prec::Level>(ThisPrec + !isRightAssoc)); 360 RHSIsInitList = false; 361 362 if (RHS.isInvalid()) 363 LHS = ExprError(); 364 365 NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator, 366 getLangOpts().CPlusPlus11); 367 } 368 assert(NextTokPrec <= ThisPrec && "Recursion didn't work!"); 369 370 if (!RHS.isInvalid() && RHSIsInitList) { 371 if (ThisPrec == prec::Assignment) { 372 Diag(OpToken, diag::warn_cxx98_compat_generalized_initializer_lists) 373 << Actions.getExprRange(RHS.get()); 374 } else { 375 Diag(OpToken, diag::err_init_list_bin_op) 376 << /*RHS*/1 << PP.getSpelling(OpToken) 377 << Actions.getExprRange(RHS.get()); 378 LHS = ExprError(); 379 } 380 } 381 382 if (!LHS.isInvalid()) { 383 // Combine the LHS and RHS into the LHS (e.g. build AST). 384 if (TernaryMiddle.isInvalid()) { 385 // If we're using '>>' as an operator within a template 386 // argument list (in C++98), suggest the addition of 387 // parentheses so that the code remains well-formed in C++0x. 388 if (!GreaterThanIsOperator && OpToken.is(tok::greatergreater)) 389 SuggestParentheses(OpToken.getLocation(), 390 diag::warn_cxx11_right_shift_in_template_arg, 391 SourceRange(Actions.getExprRange(LHS.get()).getBegin(), 392 Actions.getExprRange(RHS.get()).getEnd())); 393 394 LHS = Actions.ActOnBinOp(getCurScope(), OpToken.getLocation(), 395 OpToken.getKind(), LHS.take(), RHS.take()); 396 } else 397 LHS = Actions.ActOnConditionalOp(OpToken.getLocation(), ColonLoc, 398 LHS.take(), TernaryMiddle.take(), 399 RHS.take()); 400 } 401 } 402} 403 404/// \brief Parse a cast-expression, or, if \p isUnaryExpression is true, 405/// parse a unary-expression. 406/// 407/// \p isAddressOfOperand exists because an id-expression that is the 408/// operand of address-of gets special treatment due to member pointers. 409/// 410ExprResult Parser::ParseCastExpression(bool isUnaryExpression, 411 bool isAddressOfOperand, 412 TypeCastState isTypeCast) { 413 bool NotCastExpr; 414 ExprResult Res = ParseCastExpression(isUnaryExpression, 415 isAddressOfOperand, 416 NotCastExpr, 417 isTypeCast); 418 if (NotCastExpr) 419 Diag(Tok, diag::err_expected_expression); 420 return Res; 421} 422 423namespace { 424class CastExpressionIdValidator : public CorrectionCandidateCallback { 425 public: 426 CastExpressionIdValidator(bool AllowTypes, bool AllowNonTypes) 427 : AllowNonTypes(AllowNonTypes) { 428 WantTypeSpecifiers = AllowTypes; 429 } 430 431 bool ValidateCandidate(const TypoCorrection &candidate) override { 432 NamedDecl *ND = candidate.getCorrectionDecl(); 433 if (!ND) 434 return candidate.isKeyword(); 435 436 if (isa<TypeDecl>(ND)) 437 return WantTypeSpecifiers; 438 return AllowNonTypes; 439 } 440 441 private: 442 bool AllowNonTypes; 443}; 444} 445 446/// \brief Parse a cast-expression, or, if \pisUnaryExpression is true, parse 447/// a unary-expression. 448/// 449/// \p isAddressOfOperand exists because an id-expression that is the operand 450/// of address-of gets special treatment due to member pointers. NotCastExpr 451/// is set to true if the token is not the start of a cast-expression, and no 452/// diagnostic is emitted in this case. 453/// 454/// \verbatim 455/// cast-expression: [C99 6.5.4] 456/// unary-expression 457/// '(' type-name ')' cast-expression 458/// 459/// unary-expression: [C99 6.5.3] 460/// postfix-expression 461/// '++' unary-expression 462/// '--' unary-expression 463/// unary-operator cast-expression 464/// 'sizeof' unary-expression 465/// 'sizeof' '(' type-name ')' 466/// [C++11] 'sizeof' '...' '(' identifier ')' 467/// [GNU] '__alignof' unary-expression 468/// [GNU] '__alignof' '(' type-name ')' 469/// [C11] '_Alignof' '(' type-name ')' 470/// [C++11] 'alignof' '(' type-id ')' 471/// [GNU] '&&' identifier 472/// [C++11] 'noexcept' '(' expression ')' [C++11 5.3.7] 473/// [C++] new-expression 474/// [C++] delete-expression 475/// 476/// unary-operator: one of 477/// '&' '*' '+' '-' '~' '!' 478/// [GNU] '__extension__' '__real' '__imag' 479/// 480/// primary-expression: [C99 6.5.1] 481/// [C99] identifier 482/// [C++] id-expression 483/// constant 484/// string-literal 485/// [C++] boolean-literal [C++ 2.13.5] 486/// [C++11] 'nullptr' [C++11 2.14.7] 487/// [C++11] user-defined-literal 488/// '(' expression ')' 489/// [C11] generic-selection 490/// '__func__' [C99 6.4.2.2] 491/// [GNU] '__FUNCTION__' 492/// [MS] '__FUNCDNAME__' 493/// [MS] 'L__FUNCTION__' 494/// [GNU] '__PRETTY_FUNCTION__' 495/// [GNU] '(' compound-statement ')' 496/// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' 497/// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' 498/// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' 499/// assign-expr ')' 500/// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' 501/// [GNU] '__null' 502/// [OBJC] '[' objc-message-expr ']' 503/// [OBJC] '\@selector' '(' objc-selector-arg ')' 504/// [OBJC] '\@protocol' '(' identifier ')' 505/// [OBJC] '\@encode' '(' type-name ')' 506/// [OBJC] objc-string-literal 507/// [C++] simple-type-specifier '(' expression-list[opt] ')' [C++ 5.2.3] 508/// [C++11] simple-type-specifier braced-init-list [C++11 5.2.3] 509/// [C++] typename-specifier '(' expression-list[opt] ')' [C++ 5.2.3] 510/// [C++11] typename-specifier braced-init-list [C++11 5.2.3] 511/// [C++] 'const_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 512/// [C++] 'dynamic_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 513/// [C++] 'reinterpret_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 514/// [C++] 'static_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 515/// [C++] 'typeid' '(' expression ')' [C++ 5.2p1] 516/// [C++] 'typeid' '(' type-id ')' [C++ 5.2p1] 517/// [C++] 'this' [C++ 9.3.2] 518/// [G++] unary-type-trait '(' type-id ')' 519/// [G++] binary-type-trait '(' type-id ',' type-id ')' [TODO] 520/// [EMBT] array-type-trait '(' type-id ',' integer ')' 521/// [clang] '^' block-literal 522/// 523/// constant: [C99 6.4.4] 524/// integer-constant 525/// floating-constant 526/// enumeration-constant -> identifier 527/// character-constant 528/// 529/// id-expression: [C++ 5.1] 530/// unqualified-id 531/// qualified-id 532/// 533/// unqualified-id: [C++ 5.1] 534/// identifier 535/// operator-function-id 536/// conversion-function-id 537/// '~' class-name 538/// template-id 539/// 540/// new-expression: [C++ 5.3.4] 541/// '::'[opt] 'new' new-placement[opt] new-type-id 542/// new-initializer[opt] 543/// '::'[opt] 'new' new-placement[opt] '(' type-id ')' 544/// new-initializer[opt] 545/// 546/// delete-expression: [C++ 5.3.5] 547/// '::'[opt] 'delete' cast-expression 548/// '::'[opt] 'delete' '[' ']' cast-expression 549/// 550/// [GNU/Embarcadero] unary-type-trait: 551/// '__is_arithmetic' 552/// '__is_floating_point' 553/// '__is_integral' 554/// '__is_lvalue_expr' 555/// '__is_rvalue_expr' 556/// '__is_complete_type' 557/// '__is_void' 558/// '__is_array' 559/// '__is_function' 560/// '__is_reference' 561/// '__is_lvalue_reference' 562/// '__is_rvalue_reference' 563/// '__is_fundamental' 564/// '__is_object' 565/// '__is_scalar' 566/// '__is_compound' 567/// '__is_pointer' 568/// '__is_member_object_pointer' 569/// '__is_member_function_pointer' 570/// '__is_member_pointer' 571/// '__is_const' 572/// '__is_volatile' 573/// '__is_trivial' 574/// '__is_standard_layout' 575/// '__is_signed' 576/// '__is_unsigned' 577/// 578/// [GNU] unary-type-trait: 579/// '__has_nothrow_assign' 580/// '__has_nothrow_copy' 581/// '__has_nothrow_constructor' 582/// '__has_trivial_assign' [TODO] 583/// '__has_trivial_copy' [TODO] 584/// '__has_trivial_constructor' 585/// '__has_trivial_destructor' 586/// '__has_virtual_destructor' 587/// '__is_abstract' [TODO] 588/// '__is_class' 589/// '__is_empty' [TODO] 590/// '__is_enum' 591/// '__is_final' 592/// '__is_pod' 593/// '__is_polymorphic' 594/// '__is_sealed' [MS] 595/// '__is_trivial' 596/// '__is_union' 597/// 598/// [Clang] unary-type-trait: 599/// '__trivially_copyable' 600/// 601/// binary-type-trait: 602/// [GNU] '__is_base_of' 603/// [MS] '__is_convertible_to' 604/// '__is_convertible' 605/// '__is_same' 606/// 607/// [Embarcadero] array-type-trait: 608/// '__array_rank' 609/// '__array_extent' 610/// 611/// [Embarcadero] expression-trait: 612/// '__is_lvalue_expr' 613/// '__is_rvalue_expr' 614/// \endverbatim 615/// 616ExprResult Parser::ParseCastExpression(bool isUnaryExpression, 617 bool isAddressOfOperand, 618 bool &NotCastExpr, 619 TypeCastState isTypeCast) { 620 ExprResult Res; 621 tok::TokenKind SavedKind = Tok.getKind(); 622 NotCastExpr = false; 623 624 // This handles all of cast-expression, unary-expression, postfix-expression, 625 // and primary-expression. We handle them together like this for efficiency 626 // and to simplify handling of an expression starting with a '(' token: which 627 // may be one of a parenthesized expression, cast-expression, compound literal 628 // expression, or statement expression. 629 // 630 // If the parsed tokens consist of a primary-expression, the cases below 631 // break out of the switch; at the end we call ParsePostfixExpressionSuffix 632 // to handle the postfix expression suffixes. Cases that cannot be followed 633 // by postfix exprs should return without invoking 634 // ParsePostfixExpressionSuffix. 635 switch (SavedKind) { 636 case tok::l_paren: { 637 // If this expression is limited to being a unary-expression, the parent can 638 // not start a cast expression. 639 ParenParseOption ParenExprType = 640 (isUnaryExpression && !getLangOpts().CPlusPlus) ? CompoundLiteral 641 : CastExpr; 642 ParsedType CastTy; 643 SourceLocation RParenLoc; 644 Res = ParseParenExpression(ParenExprType, false/*stopIfCastExr*/, 645 isTypeCast == IsTypeCast, CastTy, RParenLoc); 646 647 switch (ParenExprType) { 648 case SimpleExpr: break; // Nothing else to do. 649 case CompoundStmt: break; // Nothing else to do. 650 case CompoundLiteral: 651 // We parsed '(' type-name ')' '{' ... '}'. If any suffixes of 652 // postfix-expression exist, parse them now. 653 break; 654 case CastExpr: 655 // We have parsed the cast-expression and no postfix-expr pieces are 656 // following. 657 return Res; 658 } 659 660 break; 661 } 662 663 // primary-expression 664 case tok::numeric_constant: 665 // constant: integer-constant 666 // constant: floating-constant 667 668 Res = Actions.ActOnNumericConstant(Tok, /*UDLScope*/getCurScope()); 669 ConsumeToken(); 670 break; 671 672 case tok::kw_true: 673 case tok::kw_false: 674 return ParseCXXBoolLiteral(); 675 676 case tok::kw___objc_yes: 677 case tok::kw___objc_no: 678 return ParseObjCBoolLiteral(); 679 680 case tok::kw_nullptr: 681 Diag(Tok, diag::warn_cxx98_compat_nullptr); 682 return Actions.ActOnCXXNullPtrLiteral(ConsumeToken()); 683 684 case tok::annot_primary_expr: 685 assert(Res.get() == nullptr && "Stray primary-expression annotation?"); 686 Res = getExprAnnotation(Tok); 687 ConsumeToken(); 688 break; 689 690 case tok::kw_decltype: 691 // Annotate the token and tail recurse. 692 if (TryAnnotateTypeOrScopeToken()) 693 return ExprError(); 694 assert(Tok.isNot(tok::kw_decltype)); 695 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 696 697 case tok::identifier: { // primary-expression: identifier 698 // unqualified-id: identifier 699 // constant: enumeration-constant 700 // Turn a potentially qualified name into a annot_typename or 701 // annot_cxxscope if it would be valid. This handles things like x::y, etc. 702 if (getLangOpts().CPlusPlus) { 703 // Avoid the unnecessary parse-time lookup in the common case 704 // where the syntax forbids a type. 705 const Token &Next = NextToken(); 706 707 // If this identifier was reverted from a token ID, and the next token 708 // is a parenthesis, this is likely to be a use of a type trait. Check 709 // those tokens. 710 if (Next.is(tok::l_paren) && Tok.is(tok::identifier) && 711 Tok.getIdentifierInfo()->hasRevertedTokenIDToIdentifier() && 712 TryIdentKeywordUpgrade()) 713 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 714 NotCastExpr, isTypeCast); 715 716 if (Next.is(tok::coloncolon) || 717 (!ColonIsSacred && Next.is(tok::colon)) || 718 Next.is(tok::less) || 719 Next.is(tok::l_paren) || 720 Next.is(tok::l_brace)) { 721 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. 722 if (TryAnnotateTypeOrScopeToken()) 723 return ExprError(); 724 if (!Tok.is(tok::identifier)) 725 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 726 } 727 } 728 729 // Consume the identifier so that we can see if it is followed by a '(' or 730 // '.'. 731 IdentifierInfo &II = *Tok.getIdentifierInfo(); 732 SourceLocation ILoc = ConsumeToken(); 733 734 // Support 'Class.property' and 'super.property' notation. 735 if (getLangOpts().ObjC1 && Tok.is(tok::period) && 736 (Actions.getTypeName(II, ILoc, getCurScope()) || 737 // Allow the base to be 'super' if in an objc-method. 738 (&II == Ident_super && getCurScope()->isInObjcMethodScope()))) { 739 ConsumeToken(); 740 741 // Allow either an identifier or the keyword 'class' (in C++). 742 if (Tok.isNot(tok::identifier) && 743 !(getLangOpts().CPlusPlus && Tok.is(tok::kw_class))) { 744 Diag(Tok, diag::err_expected_property_name); 745 return ExprError(); 746 } 747 IdentifierInfo &PropertyName = *Tok.getIdentifierInfo(); 748 SourceLocation PropertyLoc = ConsumeToken(); 749 750 Res = Actions.ActOnClassPropertyRefExpr(II, PropertyName, 751 ILoc, PropertyLoc); 752 break; 753 } 754 755 // In an Objective-C method, if we have "super" followed by an identifier, 756 // the token sequence is ill-formed. However, if there's a ':' or ']' after 757 // that identifier, this is probably a message send with a missing open 758 // bracket. Treat it as such. 759 if (getLangOpts().ObjC1 && &II == Ident_super && !InMessageExpression && 760 getCurScope()->isInObjcMethodScope() && 761 ((Tok.is(tok::identifier) && 762 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) || 763 Tok.is(tok::code_completion))) { 764 Res = ParseObjCMessageExpressionBody(SourceLocation(), ILoc, ParsedType(), 765 nullptr); 766 break; 767 } 768 769 // If we have an Objective-C class name followed by an identifier 770 // and either ':' or ']', this is an Objective-C class message 771 // send that's missing the opening '['. Recovery 772 // appropriately. Also take this path if we're performing code 773 // completion after an Objective-C class name. 774 if (getLangOpts().ObjC1 && 775 ((Tok.is(tok::identifier) && !InMessageExpression) || 776 Tok.is(tok::code_completion))) { 777 const Token& Next = NextToken(); 778 if (Tok.is(tok::code_completion) || 779 Next.is(tok::colon) || Next.is(tok::r_square)) 780 if (ParsedType Typ = Actions.getTypeName(II, ILoc, getCurScope())) 781 if (Typ.get()->isObjCObjectOrInterfaceType()) { 782 // Fake up a Declarator to use with ActOnTypeName. 783 DeclSpec DS(AttrFactory); 784 DS.SetRangeStart(ILoc); 785 DS.SetRangeEnd(ILoc); 786 const char *PrevSpec = nullptr; 787 unsigned DiagID; 788 DS.SetTypeSpecType(TST_typename, ILoc, PrevSpec, DiagID, Typ, 789 Actions.getASTContext().getPrintingPolicy()); 790 791 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 792 TypeResult Ty = Actions.ActOnTypeName(getCurScope(), 793 DeclaratorInfo); 794 if (Ty.isInvalid()) 795 break; 796 797 Res = ParseObjCMessageExpressionBody(SourceLocation(), 798 SourceLocation(), 799 Ty.get(), nullptr); 800 break; 801 } 802 } 803 804 // Make sure to pass down the right value for isAddressOfOperand. 805 if (isAddressOfOperand && isPostfixExpressionSuffixStart()) 806 isAddressOfOperand = false; 807 808 // Function designators are allowed to be undeclared (C99 6.5.1p2), so we 809 // need to know whether or not this identifier is a function designator or 810 // not. 811 UnqualifiedId Name; 812 CXXScopeSpec ScopeSpec; 813 SourceLocation TemplateKWLoc; 814 CastExpressionIdValidator Validator(isTypeCast != NotTypeCast, 815 isTypeCast != IsTypeCast); 816 Name.setIdentifier(&II, ILoc); 817 Res = Actions.ActOnIdExpression(getCurScope(), ScopeSpec, TemplateKWLoc, 818 Name, Tok.is(tok::l_paren), 819 isAddressOfOperand, &Validator); 820 break; 821 } 822 case tok::char_constant: // constant: character-constant 823 case tok::wide_char_constant: 824 case tok::utf16_char_constant: 825 case tok::utf32_char_constant: 826 Res = Actions.ActOnCharacterConstant(Tok, /*UDLScope*/getCurScope()); 827 ConsumeToken(); 828 break; 829 case tok::kw___func__: // primary-expression: __func__ [C99 6.4.2.2] 830 case tok::kw___FUNCTION__: // primary-expression: __FUNCTION__ [GNU] 831 case tok::kw___FUNCDNAME__: // primary-expression: __FUNCDNAME__ [MS] 832 case tok::kw___FUNCSIG__: // primary-expression: __FUNCSIG__ [MS] 833 case tok::kw_L__FUNCTION__: // primary-expression: L__FUNCTION__ [MS] 834 case tok::kw___PRETTY_FUNCTION__: // primary-expression: __P..Y_F..N__ [GNU] 835 Res = Actions.ActOnPredefinedExpr(Tok.getLocation(), SavedKind); 836 ConsumeToken(); 837 break; 838 case tok::string_literal: // primary-expression: string-literal 839 case tok::wide_string_literal: 840 case tok::utf8_string_literal: 841 case tok::utf16_string_literal: 842 case tok::utf32_string_literal: 843 Res = ParseStringLiteralExpression(true); 844 break; 845 case tok::kw__Generic: // primary-expression: generic-selection [C11 6.5.1] 846 Res = ParseGenericSelectionExpression(); 847 break; 848 case tok::kw___builtin_va_arg: 849 case tok::kw___builtin_offsetof: 850 case tok::kw___builtin_choose_expr: 851 case tok::kw___builtin_astype: // primary-expression: [OCL] as_type() 852 case tok::kw___builtin_convertvector: 853 return ParseBuiltinPrimaryExpression(); 854 case tok::kw___null: 855 return Actions.ActOnGNUNullExpr(ConsumeToken()); 856 857 case tok::plusplus: // unary-expression: '++' unary-expression [C99] 858 case tok::minusminus: { // unary-expression: '--' unary-expression [C99] 859 // C++ [expr.unary] has: 860 // unary-expression: 861 // ++ cast-expression 862 // -- cast-expression 863 SourceLocation SavedLoc = ConsumeToken(); 864 Res = ParseCastExpression(!getLangOpts().CPlusPlus); 865 if (!Res.isInvalid()) 866 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 867 return Res; 868 } 869 case tok::amp: { // unary-expression: '&' cast-expression 870 // Special treatment because of member pointers 871 SourceLocation SavedLoc = ConsumeToken(); 872 Res = ParseCastExpression(false, true); 873 if (!Res.isInvalid()) 874 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 875 return Res; 876 } 877 878 case tok::star: // unary-expression: '*' cast-expression 879 case tok::plus: // unary-expression: '+' cast-expression 880 case tok::minus: // unary-expression: '-' cast-expression 881 case tok::tilde: // unary-expression: '~' cast-expression 882 case tok::exclaim: // unary-expression: '!' cast-expression 883 case tok::kw___real: // unary-expression: '__real' cast-expression [GNU] 884 case tok::kw___imag: { // unary-expression: '__imag' cast-expression [GNU] 885 SourceLocation SavedLoc = ConsumeToken(); 886 Res = ParseCastExpression(false); 887 if (!Res.isInvalid()) 888 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 889 return Res; 890 } 891 892 case tok::kw___extension__:{//unary-expression:'__extension__' cast-expr [GNU] 893 // __extension__ silences extension warnings in the subexpression. 894 ExtensionRAIIObject O(Diags); // Use RAII to do this. 895 SourceLocation SavedLoc = ConsumeToken(); 896 Res = ParseCastExpression(false); 897 if (!Res.isInvalid()) 898 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 899 return Res; 900 } 901 case tok::kw__Alignof: // unary-expression: '_Alignof' '(' type-name ')' 902 if (!getLangOpts().C11) 903 Diag(Tok, diag::ext_c11_alignment) << Tok.getName(); 904 // fallthrough 905 case tok::kw_alignof: // unary-expression: 'alignof' '(' type-id ')' 906 case tok::kw___alignof: // unary-expression: '__alignof' unary-expression 907 // unary-expression: '__alignof' '(' type-name ')' 908 case tok::kw_sizeof: // unary-expression: 'sizeof' unary-expression 909 // unary-expression: 'sizeof' '(' type-name ')' 910 case tok::kw_vec_step: // unary-expression: OpenCL 'vec_step' expression 911 return ParseUnaryExprOrTypeTraitExpression(); 912 case tok::ampamp: { // unary-expression: '&&' identifier 913 SourceLocation AmpAmpLoc = ConsumeToken(); 914 if (Tok.isNot(tok::identifier)) 915 return ExprError(Diag(Tok, diag::err_expected) << tok::identifier); 916 917 if (getCurScope()->getFnParent() == nullptr) 918 return ExprError(Diag(Tok, diag::err_address_of_label_outside_fn)); 919 920 Diag(AmpAmpLoc, diag::ext_gnu_address_of_label); 921 LabelDecl *LD = Actions.LookupOrCreateLabel(Tok.getIdentifierInfo(), 922 Tok.getLocation()); 923 Res = Actions.ActOnAddrLabel(AmpAmpLoc, Tok.getLocation(), LD); 924 ConsumeToken(); 925 return Res; 926 } 927 case tok::kw_const_cast: 928 case tok::kw_dynamic_cast: 929 case tok::kw_reinterpret_cast: 930 case tok::kw_static_cast: 931 Res = ParseCXXCasts(); 932 break; 933 case tok::kw_typeid: 934 Res = ParseCXXTypeid(); 935 break; 936 case tok::kw___uuidof: 937 Res = ParseCXXUuidof(); 938 break; 939 case tok::kw_this: 940 Res = ParseCXXThis(); 941 break; 942 943 case tok::annot_typename: 944 if (isStartOfObjCClassMessageMissingOpenBracket()) { 945 ParsedType Type = getTypeAnnotation(Tok); 946 947 // Fake up a Declarator to use with ActOnTypeName. 948 DeclSpec DS(AttrFactory); 949 DS.SetRangeStart(Tok.getLocation()); 950 DS.SetRangeEnd(Tok.getLastLoc()); 951 952 const char *PrevSpec = nullptr; 953 unsigned DiagID; 954 DS.SetTypeSpecType(TST_typename, Tok.getAnnotationEndLoc(), 955 PrevSpec, DiagID, Type, 956 Actions.getASTContext().getPrintingPolicy()); 957 958 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 959 TypeResult Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 960 if (Ty.isInvalid()) 961 break; 962 963 ConsumeToken(); 964 Res = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), 965 Ty.get(), nullptr); 966 break; 967 } 968 // Fall through 969 970 case tok::annot_decltype: 971 case tok::kw_char: 972 case tok::kw_wchar_t: 973 case tok::kw_char16_t: 974 case tok::kw_char32_t: 975 case tok::kw_bool: 976 case tok::kw_short: 977 case tok::kw_int: 978 case tok::kw_long: 979 case tok::kw___int64: 980 case tok::kw___int128: 981 case tok::kw_signed: 982 case tok::kw_unsigned: 983 case tok::kw_half: 984 case tok::kw_float: 985 case tok::kw_double: 986 case tok::kw_void: 987 case tok::kw_typename: 988 case tok::kw_typeof: 989 case tok::kw___vector: { 990 if (!getLangOpts().CPlusPlus) { 991 Diag(Tok, diag::err_expected_expression); 992 return ExprError(); 993 } 994 995 if (SavedKind == tok::kw_typename) { 996 // postfix-expression: typename-specifier '(' expression-list[opt] ')' 997 // typename-specifier braced-init-list 998 if (TryAnnotateTypeOrScopeToken()) 999 return ExprError(); 1000 1001 if (!Actions.isSimpleTypeSpecifier(Tok.getKind())) 1002 // We are trying to parse a simple-type-specifier but might not get such 1003 // a token after error recovery. 1004 return ExprError(); 1005 } 1006 1007 // postfix-expression: simple-type-specifier '(' expression-list[opt] ')' 1008 // simple-type-specifier braced-init-list 1009 // 1010 DeclSpec DS(AttrFactory); 1011 1012 ParseCXXSimpleTypeSpecifier(DS); 1013 if (Tok.isNot(tok::l_paren) && 1014 (!getLangOpts().CPlusPlus11 || Tok.isNot(tok::l_brace))) 1015 return ExprError(Diag(Tok, diag::err_expected_lparen_after_type) 1016 << DS.getSourceRange()); 1017 1018 if (Tok.is(tok::l_brace)) 1019 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); 1020 1021 Res = ParseCXXTypeConstructExpression(DS); 1022 break; 1023 } 1024 1025 case tok::annot_cxxscope: { // [C++] id-expression: qualified-id 1026 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. 1027 // (We can end up in this situation after tentative parsing.) 1028 if (TryAnnotateTypeOrScopeToken()) 1029 return ExprError(); 1030 if (!Tok.is(tok::annot_cxxscope)) 1031 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 1032 NotCastExpr, isTypeCast); 1033 1034 Token Next = NextToken(); 1035 if (Next.is(tok::annot_template_id)) { 1036 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Next); 1037 if (TemplateId->Kind == TNK_Type_template) { 1038 // We have a qualified template-id that we know refers to a 1039 // type, translate it into a type and continue parsing as a 1040 // cast expression. 1041 CXXScopeSpec SS; 1042 ParseOptionalCXXScopeSpecifier(SS, ParsedType(), 1043 /*EnteringContext=*/false); 1044 AnnotateTemplateIdTokenAsType(); 1045 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 1046 NotCastExpr, isTypeCast); 1047 } 1048 } 1049 1050 // Parse as an id-expression. 1051 Res = ParseCXXIdExpression(isAddressOfOperand); 1052 break; 1053 } 1054 1055 case tok::annot_template_id: { // [C++] template-id 1056 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok); 1057 if (TemplateId->Kind == TNK_Type_template) { 1058 // We have a template-id that we know refers to a type, 1059 // translate it into a type and continue parsing as a cast 1060 // expression. 1061 AnnotateTemplateIdTokenAsType(); 1062 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 1063 NotCastExpr, isTypeCast); 1064 } 1065 1066 // Fall through to treat the template-id as an id-expression. 1067 } 1068 1069 case tok::kw_operator: // [C++] id-expression: operator/conversion-function-id 1070 Res = ParseCXXIdExpression(isAddressOfOperand); 1071 break; 1072 1073 case tok::coloncolon: { 1074 // ::foo::bar -> global qualified name etc. If TryAnnotateTypeOrScopeToken 1075 // annotates the token, tail recurse. 1076 if (TryAnnotateTypeOrScopeToken()) 1077 return ExprError(); 1078 if (!Tok.is(tok::coloncolon)) 1079 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 1080 1081 // ::new -> [C++] new-expression 1082 // ::delete -> [C++] delete-expression 1083 SourceLocation CCLoc = ConsumeToken(); 1084 if (Tok.is(tok::kw_new)) 1085 return ParseCXXNewExpression(true, CCLoc); 1086 if (Tok.is(tok::kw_delete)) 1087 return ParseCXXDeleteExpression(true, CCLoc); 1088 1089 // This is not a type name or scope specifier, it is an invalid expression. 1090 Diag(CCLoc, diag::err_expected_expression); 1091 return ExprError(); 1092 } 1093 1094 case tok::kw_new: // [C++] new-expression 1095 return ParseCXXNewExpression(false, Tok.getLocation()); 1096 1097 case tok::kw_delete: // [C++] delete-expression 1098 return ParseCXXDeleteExpression(false, Tok.getLocation()); 1099 1100 case tok::kw_noexcept: { // [C++0x] 'noexcept' '(' expression ')' 1101 Diag(Tok, diag::warn_cxx98_compat_noexcept_expr); 1102 SourceLocation KeyLoc = ConsumeToken(); 1103 BalancedDelimiterTracker T(*this, tok::l_paren); 1104 1105 if (T.expectAndConsume(diag::err_expected_lparen_after, "noexcept")) 1106 return ExprError(); 1107 // C++11 [expr.unary.noexcept]p1: 1108 // The noexcept operator determines whether the evaluation of its operand, 1109 // which is an unevaluated operand, can throw an exception. 1110 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated); 1111 ExprResult Result = ParseExpression(); 1112 1113 T.consumeClose(); 1114 1115 if (!Result.isInvalid()) 1116 Result = Actions.ActOnNoexceptExpr(KeyLoc, T.getOpenLocation(), 1117 Result.take(), T.getCloseLocation()); 1118 return Result; 1119 } 1120 1121#define TYPE_TRAIT(N,Spelling,K) \ 1122 case tok::kw_##Spelling: 1123#include "clang/Basic/TokenKinds.def" 1124 return ParseTypeTrait(); 1125 1126 case tok::kw___array_rank: 1127 case tok::kw___array_extent: 1128 return ParseArrayTypeTrait(); 1129 1130 case tok::kw___is_lvalue_expr: 1131 case tok::kw___is_rvalue_expr: 1132 return ParseExpressionTrait(); 1133 1134 case tok::at: { 1135 SourceLocation AtLoc = ConsumeToken(); 1136 return ParseObjCAtExpression(AtLoc); 1137 } 1138 case tok::caret: 1139 Res = ParseBlockLiteralExpression(); 1140 break; 1141 case tok::code_completion: { 1142 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); 1143 cutOffParsing(); 1144 return ExprError(); 1145 } 1146 case tok::l_square: 1147 if (getLangOpts().CPlusPlus11) { 1148 if (getLangOpts().ObjC1) { 1149 // C++11 lambda expressions and Objective-C message sends both start with a 1150 // square bracket. There are three possibilities here: 1151 // we have a valid lambda expression, we have an invalid lambda 1152 // expression, or we have something that doesn't appear to be a lambda. 1153 // If we're in the last case, we fall back to ParseObjCMessageExpression. 1154 Res = TryParseLambdaExpression(); 1155 if (!Res.isInvalid() && !Res.get()) 1156 Res = ParseObjCMessageExpression(); 1157 break; 1158 } 1159 Res = ParseLambdaExpression(); 1160 break; 1161 } 1162 if (getLangOpts().ObjC1) { 1163 Res = ParseObjCMessageExpression(); 1164 break; 1165 } 1166 // FALL THROUGH. 1167 default: 1168 NotCastExpr = true; 1169 return ExprError(); 1170 } 1171 1172 // These can be followed by postfix-expr pieces. 1173 return ParsePostfixExpressionSuffix(Res); 1174} 1175 1176/// \brief Once the leading part of a postfix-expression is parsed, this 1177/// method parses any suffixes that apply. 1178/// 1179/// \verbatim 1180/// postfix-expression: [C99 6.5.2] 1181/// primary-expression 1182/// postfix-expression '[' expression ']' 1183/// postfix-expression '[' braced-init-list ']' 1184/// postfix-expression '(' argument-expression-list[opt] ')' 1185/// postfix-expression '.' identifier 1186/// postfix-expression '->' identifier 1187/// postfix-expression '++' 1188/// postfix-expression '--' 1189/// '(' type-name ')' '{' initializer-list '}' 1190/// '(' type-name ')' '{' initializer-list ',' '}' 1191/// 1192/// argument-expression-list: [C99 6.5.2] 1193/// argument-expression ...[opt] 1194/// argument-expression-list ',' assignment-expression ...[opt] 1195/// \endverbatim 1196ExprResult 1197Parser::ParsePostfixExpressionSuffix(ExprResult LHS) { 1198 // Now that the primary-expression piece of the postfix-expression has been 1199 // parsed, see if there are any postfix-expression pieces here. 1200 SourceLocation Loc; 1201 while (1) { 1202 switch (Tok.getKind()) { 1203 case tok::code_completion: 1204 if (InMessageExpression) 1205 return LHS; 1206 1207 Actions.CodeCompletePostfixExpression(getCurScope(), LHS); 1208 cutOffParsing(); 1209 return ExprError(); 1210 1211 case tok::identifier: 1212 // If we see identifier: after an expression, and we're not already in a 1213 // message send, then this is probably a message send with a missing 1214 // opening bracket '['. 1215 if (getLangOpts().ObjC1 && !InMessageExpression && 1216 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) { 1217 LHS = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), 1218 ParsedType(), LHS.get()); 1219 break; 1220 } 1221 1222 // Fall through; this isn't a message send. 1223 1224 default: // Not a postfix-expression suffix. 1225 return LHS; 1226 case tok::l_square: { // postfix-expression: p-e '[' expression ']' 1227 // If we have a array postfix expression that starts on a new line and 1228 // Objective-C is enabled, it is highly likely that the user forgot a 1229 // semicolon after the base expression and that the array postfix-expr is 1230 // actually another message send. In this case, do some look-ahead to see 1231 // if the contents of the square brackets are obviously not a valid 1232 // expression and recover by pretending there is no suffix. 1233 if (getLangOpts().ObjC1 && Tok.isAtStartOfLine() && 1234 isSimpleObjCMessageExpression()) 1235 return LHS; 1236 1237 // Reject array indices starting with a lambda-expression. '[[' is 1238 // reserved for attributes. 1239 if (CheckProhibitedCXX11Attribute()) 1240 return ExprError(); 1241 1242 BalancedDelimiterTracker T(*this, tok::l_square); 1243 T.consumeOpen(); 1244 Loc = T.getOpenLocation(); 1245 ExprResult Idx; 1246 if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) { 1247 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); 1248 Idx = ParseBraceInitializer(); 1249 } else 1250 Idx = ParseExpression(); 1251 1252 SourceLocation RLoc = Tok.getLocation(); 1253 1254 if (!LHS.isInvalid() && !Idx.isInvalid() && Tok.is(tok::r_square)) { 1255 LHS = Actions.ActOnArraySubscriptExpr(getCurScope(), LHS.take(), Loc, 1256 Idx.take(), RLoc); 1257 } else 1258 LHS = ExprError(); 1259 1260 // Match the ']'. 1261 T.consumeClose(); 1262 break; 1263 } 1264 1265 case tok::l_paren: // p-e: p-e '(' argument-expression-list[opt] ')' 1266 case tok::lesslessless: { // p-e: p-e '<<<' argument-expression-list '>>>' 1267 // '(' argument-expression-list[opt] ')' 1268 tok::TokenKind OpKind = Tok.getKind(); 1269 InMessageExpressionRAIIObject InMessage(*this, false); 1270 1271 Expr *ExecConfig = nullptr; 1272 1273 BalancedDelimiterTracker PT(*this, tok::l_paren); 1274 1275 if (OpKind == tok::lesslessless) { 1276 ExprVector ExecConfigExprs; 1277 CommaLocsTy ExecConfigCommaLocs; 1278 SourceLocation OpenLoc = ConsumeToken(); 1279 1280 if (ParseSimpleExpressionList(ExecConfigExprs, ExecConfigCommaLocs)) { 1281 LHS = ExprError(); 1282 } 1283 1284 SourceLocation CloseLoc; 1285 if (TryConsumeToken(tok::greatergreatergreater, CloseLoc)) { 1286 } else if (LHS.isInvalid()) { 1287 SkipUntil(tok::greatergreatergreater, StopAtSemi); 1288 } else { 1289 // There was an error closing the brackets 1290 Diag(Tok, diag::err_expected) << tok::greatergreatergreater; 1291 Diag(OpenLoc, diag::note_matching) << tok::lesslessless; 1292 SkipUntil(tok::greatergreatergreater, StopAtSemi); 1293 LHS = ExprError(); 1294 } 1295 1296 if (!LHS.isInvalid()) { 1297 if (ExpectAndConsume(tok::l_paren)) 1298 LHS = ExprError(); 1299 else 1300 Loc = PrevTokLocation; 1301 } 1302 1303 if (!LHS.isInvalid()) { 1304 ExprResult ECResult = Actions.ActOnCUDAExecConfigExpr(getCurScope(), 1305 OpenLoc, 1306 ExecConfigExprs, 1307 CloseLoc); 1308 if (ECResult.isInvalid()) 1309 LHS = ExprError(); 1310 else 1311 ExecConfig = ECResult.get(); 1312 } 1313 } else { 1314 PT.consumeOpen(); 1315 Loc = PT.getOpenLocation(); 1316 } 1317 1318 ExprVector ArgExprs; 1319 CommaLocsTy CommaLocs; 1320 1321 if (Tok.is(tok::code_completion)) { 1322 Actions.CodeCompleteCall(getCurScope(), LHS.get(), None); 1323 cutOffParsing(); 1324 return ExprError(); 1325 } 1326 1327 if (OpKind == tok::l_paren || !LHS.isInvalid()) { 1328 if (Tok.isNot(tok::r_paren)) { 1329 if (ParseExpressionList(ArgExprs, CommaLocs, &Sema::CodeCompleteCall, 1330 LHS.get())) { 1331 LHS = ExprError(); 1332 } 1333 } 1334 } 1335 1336 // Match the ')'. 1337 if (LHS.isInvalid()) { 1338 SkipUntil(tok::r_paren, StopAtSemi); 1339 } else if (Tok.isNot(tok::r_paren)) { 1340 PT.consumeClose(); 1341 LHS = ExprError(); 1342 } else { 1343 assert((ArgExprs.size() == 0 || 1344 ArgExprs.size()-1 == CommaLocs.size())&& 1345 "Unexpected number of commas!"); 1346 LHS = Actions.ActOnCallExpr(getCurScope(), LHS.take(), Loc, 1347 ArgExprs, Tok.getLocation(), 1348 ExecConfig); 1349 PT.consumeClose(); 1350 } 1351 1352 break; 1353 } 1354 case tok::arrow: 1355 case tok::period: { 1356 // postfix-expression: p-e '->' template[opt] id-expression 1357 // postfix-expression: p-e '.' template[opt] id-expression 1358 tok::TokenKind OpKind = Tok.getKind(); 1359 SourceLocation OpLoc = ConsumeToken(); // Eat the "." or "->" token. 1360 1361 CXXScopeSpec SS; 1362 ParsedType ObjectType; 1363 bool MayBePseudoDestructor = false; 1364 if (getLangOpts().CPlusPlus && !LHS.isInvalid()) { 1365 Expr *Base = LHS.take(); 1366 const Type* BaseType = Base->getType().getTypePtrOrNull(); 1367 if (BaseType && Tok.is(tok::l_paren) && 1368 (BaseType->isFunctionType() || 1369 BaseType->isSpecificPlaceholderType(BuiltinType::BoundMember))) { 1370 Diag(OpLoc, diag::err_function_is_not_record) 1371 << OpKind << Base->getSourceRange() 1372 << FixItHint::CreateRemoval(OpLoc); 1373 return ParsePostfixExpressionSuffix(Base); 1374 } 1375 1376 LHS = Actions.ActOnStartCXXMemberReference(getCurScope(), Base, 1377 OpLoc, OpKind, ObjectType, 1378 MayBePseudoDestructor); 1379 if (LHS.isInvalid()) 1380 break; 1381 1382 ParseOptionalCXXScopeSpecifier(SS, ObjectType, 1383 /*EnteringContext=*/false, 1384 &MayBePseudoDestructor); 1385 if (SS.isNotEmpty()) 1386 ObjectType = ParsedType(); 1387 } 1388 1389 if (Tok.is(tok::code_completion)) { 1390 // Code completion for a member access expression. 1391 Actions.CodeCompleteMemberReferenceExpr(getCurScope(), LHS.get(), 1392 OpLoc, OpKind == tok::arrow); 1393 1394 cutOffParsing(); 1395 return ExprError(); 1396 } 1397 1398 if (MayBePseudoDestructor && !LHS.isInvalid()) { 1399 LHS = ParseCXXPseudoDestructor(LHS.take(), OpLoc, OpKind, SS, 1400 ObjectType); 1401 break; 1402 } 1403 1404 // Either the action has told is that this cannot be a 1405 // pseudo-destructor expression (based on the type of base 1406 // expression), or we didn't see a '~' in the right place. We 1407 // can still parse a destructor name here, but in that case it 1408 // names a real destructor. 1409 // Allow explicit constructor calls in Microsoft mode. 1410 // FIXME: Add support for explicit call of template constructor. 1411 SourceLocation TemplateKWLoc; 1412 UnqualifiedId Name; 1413 if (getLangOpts().ObjC2 && OpKind == tok::period && Tok.is(tok::kw_class)) { 1414 // Objective-C++: 1415 // After a '.' in a member access expression, treat the keyword 1416 // 'class' as if it were an identifier. 1417 // 1418 // This hack allows property access to the 'class' method because it is 1419 // such a common method name. For other C++ keywords that are 1420 // Objective-C method names, one must use the message send syntax. 1421 IdentifierInfo *Id = Tok.getIdentifierInfo(); 1422 SourceLocation Loc = ConsumeToken(); 1423 Name.setIdentifier(Id, Loc); 1424 } else if (ParseUnqualifiedId(SS, 1425 /*EnteringContext=*/false, 1426 /*AllowDestructorName=*/true, 1427 /*AllowConstructorName=*/ 1428 getLangOpts().MicrosoftExt, 1429 ObjectType, TemplateKWLoc, Name)) 1430 LHS = ExprError(); 1431 1432 if (!LHS.isInvalid()) 1433 LHS = Actions.ActOnMemberAccessExpr(getCurScope(), LHS.take(), OpLoc, 1434 OpKind, SS, TemplateKWLoc, Name, 1435 CurParsedObjCImpl ? CurParsedObjCImpl->Dcl 1436 : nullptr, 1437 Tok.is(tok::l_paren)); 1438 break; 1439 } 1440 case tok::plusplus: // postfix-expression: postfix-expression '++' 1441 case tok::minusminus: // postfix-expression: postfix-expression '--' 1442 if (!LHS.isInvalid()) { 1443 LHS = Actions.ActOnPostfixUnaryOp(getCurScope(), Tok.getLocation(), 1444 Tok.getKind(), LHS.take()); 1445 } 1446 ConsumeToken(); 1447 break; 1448 } 1449 } 1450} 1451 1452/// ParseExprAfterUnaryExprOrTypeTrait - We parsed a typeof/sizeof/alignof/ 1453/// vec_step and we are at the start of an expression or a parenthesized 1454/// type-id. OpTok is the operand token (typeof/sizeof/alignof). Returns the 1455/// expression (isCastExpr == false) or the type (isCastExpr == true). 1456/// 1457/// \verbatim 1458/// unary-expression: [C99 6.5.3] 1459/// 'sizeof' unary-expression 1460/// 'sizeof' '(' type-name ')' 1461/// [GNU] '__alignof' unary-expression 1462/// [GNU] '__alignof' '(' type-name ')' 1463/// [C11] '_Alignof' '(' type-name ')' 1464/// [C++0x] 'alignof' '(' type-id ')' 1465/// 1466/// [GNU] typeof-specifier: 1467/// typeof ( expressions ) 1468/// typeof ( type-name ) 1469/// [GNU/C++] typeof unary-expression 1470/// 1471/// [OpenCL 1.1 6.11.12] vec_step built-in function: 1472/// vec_step ( expressions ) 1473/// vec_step ( type-name ) 1474/// \endverbatim 1475ExprResult 1476Parser::ParseExprAfterUnaryExprOrTypeTrait(const Token &OpTok, 1477 bool &isCastExpr, 1478 ParsedType &CastTy, 1479 SourceRange &CastRange) { 1480 1481 assert((OpTok.is(tok::kw_typeof) || OpTok.is(tok::kw_sizeof) || 1482 OpTok.is(tok::kw___alignof) || OpTok.is(tok::kw_alignof) || 1483 OpTok.is(tok::kw__Alignof) || OpTok.is(tok::kw_vec_step)) && 1484 "Not a typeof/sizeof/alignof/vec_step expression!"); 1485 1486 ExprResult Operand; 1487 1488 // If the operand doesn't start with an '(', it must be an expression. 1489 if (Tok.isNot(tok::l_paren)) { 1490 // If construct allows a form without parenthesis, user may forget to put 1491 // pathenthesis around type name. 1492 if (OpTok.is(tok::kw_sizeof) || OpTok.is(tok::kw___alignof) || 1493 OpTok.is(tok::kw_alignof) || OpTok.is(tok::kw__Alignof)) { 1494 if (isTypeIdUnambiguously()) { 1495 DeclSpec DS(AttrFactory); 1496 ParseSpecifierQualifierList(DS); 1497 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 1498 ParseDeclarator(DeclaratorInfo); 1499 1500 SourceLocation LParenLoc = PP.getLocForEndOfToken(OpTok.getLocation()); 1501 SourceLocation RParenLoc = PP.getLocForEndOfToken(PrevTokLocation); 1502 Diag(LParenLoc, diag::err_expected_parentheses_around_typename) 1503 << OpTok.getName() 1504 << FixItHint::CreateInsertion(LParenLoc, "(") 1505 << FixItHint::CreateInsertion(RParenLoc, ")"); 1506 isCastExpr = true; 1507 return ExprEmpty(); 1508 } 1509 } 1510 1511 isCastExpr = false; 1512 if (OpTok.is(tok::kw_typeof) && !getLangOpts().CPlusPlus) { 1513 Diag(Tok, diag::err_expected_after) << OpTok.getIdentifierInfo() 1514 << tok::l_paren; 1515 return ExprError(); 1516 } 1517 1518 Operand = ParseCastExpression(true/*isUnaryExpression*/); 1519 } else { 1520 // If it starts with a '(', we know that it is either a parenthesized 1521 // type-name, or it is a unary-expression that starts with a compound 1522 // literal, or starts with a primary-expression that is a parenthesized 1523 // expression. 1524 ParenParseOption ExprType = CastExpr; 1525 SourceLocation LParenLoc = Tok.getLocation(), RParenLoc; 1526 1527 Operand = ParseParenExpression(ExprType, true/*stopIfCastExpr*/, 1528 false, CastTy, RParenLoc); 1529 CastRange = SourceRange(LParenLoc, RParenLoc); 1530 1531 // If ParseParenExpression parsed a '(typename)' sequence only, then this is 1532 // a type. 1533 if (ExprType == CastExpr) { 1534 isCastExpr = true; 1535 return ExprEmpty(); 1536 } 1537 1538 if (getLangOpts().CPlusPlus || OpTok.isNot(tok::kw_typeof)) { 1539 // GNU typeof in C requires the expression to be parenthesized. Not so for 1540 // sizeof/alignof or in C++. Therefore, the parenthesized expression is 1541 // the start of a unary-expression, but doesn't include any postfix 1542 // pieces. Parse these now if present. 1543 if (!Operand.isInvalid()) 1544 Operand = ParsePostfixExpressionSuffix(Operand.get()); 1545 } 1546 } 1547 1548 // If we get here, the operand to the typeof/sizeof/alignof was an expresion. 1549 isCastExpr = false; 1550 return Operand; 1551} 1552 1553 1554/// \brief Parse a sizeof or alignof expression. 1555/// 1556/// \verbatim 1557/// unary-expression: [C99 6.5.3] 1558/// 'sizeof' unary-expression 1559/// 'sizeof' '(' type-name ')' 1560/// [C++11] 'sizeof' '...' '(' identifier ')' 1561/// [GNU] '__alignof' unary-expression 1562/// [GNU] '__alignof' '(' type-name ')' 1563/// [C11] '_Alignof' '(' type-name ')' 1564/// [C++11] 'alignof' '(' type-id ')' 1565/// \endverbatim 1566ExprResult Parser::ParseUnaryExprOrTypeTraitExpression() { 1567 assert((Tok.is(tok::kw_sizeof) || Tok.is(tok::kw___alignof) || 1568 Tok.is(tok::kw_alignof) || Tok.is(tok::kw__Alignof) || 1569 Tok.is(tok::kw_vec_step)) && 1570 "Not a sizeof/alignof/vec_step expression!"); 1571 Token OpTok = Tok; 1572 ConsumeToken(); 1573 1574 // [C++11] 'sizeof' '...' '(' identifier ')' 1575 if (Tok.is(tok::ellipsis) && OpTok.is(tok::kw_sizeof)) { 1576 SourceLocation EllipsisLoc = ConsumeToken(); 1577 SourceLocation LParenLoc, RParenLoc; 1578 IdentifierInfo *Name = nullptr; 1579 SourceLocation NameLoc; 1580 if (Tok.is(tok::l_paren)) { 1581 BalancedDelimiterTracker T(*this, tok::l_paren); 1582 T.consumeOpen(); 1583 LParenLoc = T.getOpenLocation(); 1584 if (Tok.is(tok::identifier)) { 1585 Name = Tok.getIdentifierInfo(); 1586 NameLoc = ConsumeToken(); 1587 T.consumeClose(); 1588 RParenLoc = T.getCloseLocation(); 1589 if (RParenLoc.isInvalid()) 1590 RParenLoc = PP.getLocForEndOfToken(NameLoc); 1591 } else { 1592 Diag(Tok, diag::err_expected_parameter_pack); 1593 SkipUntil(tok::r_paren, StopAtSemi); 1594 } 1595 } else if (Tok.is(tok::identifier)) { 1596 Name = Tok.getIdentifierInfo(); 1597 NameLoc = ConsumeToken(); 1598 LParenLoc = PP.getLocForEndOfToken(EllipsisLoc); 1599 RParenLoc = PP.getLocForEndOfToken(NameLoc); 1600 Diag(LParenLoc, diag::err_paren_sizeof_parameter_pack) 1601 << Name 1602 << FixItHint::CreateInsertion(LParenLoc, "(") 1603 << FixItHint::CreateInsertion(RParenLoc, ")"); 1604 } else { 1605 Diag(Tok, diag::err_sizeof_parameter_pack); 1606 } 1607 1608 if (!Name) 1609 return ExprError(); 1610 1611 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated, 1612 Sema::ReuseLambdaContextDecl); 1613 1614 return Actions.ActOnSizeofParameterPackExpr(getCurScope(), 1615 OpTok.getLocation(), 1616 *Name, NameLoc, 1617 RParenLoc); 1618 } 1619 1620 if (OpTok.is(tok::kw_alignof) || OpTok.is(tok::kw__Alignof)) 1621 Diag(OpTok, diag::warn_cxx98_compat_alignof); 1622 1623 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated, 1624 Sema::ReuseLambdaContextDecl); 1625 1626 bool isCastExpr; 1627 ParsedType CastTy; 1628 SourceRange CastRange; 1629 ExprResult Operand = ParseExprAfterUnaryExprOrTypeTrait(OpTok, 1630 isCastExpr, 1631 CastTy, 1632 CastRange); 1633 1634 UnaryExprOrTypeTrait ExprKind = UETT_SizeOf; 1635 if (OpTok.is(tok::kw_alignof) || OpTok.is(tok::kw___alignof) || 1636 OpTok.is(tok::kw__Alignof)) 1637 ExprKind = UETT_AlignOf; 1638 else if (OpTok.is(tok::kw_vec_step)) 1639 ExprKind = UETT_VecStep; 1640 1641 if (isCastExpr) 1642 return Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(), 1643 ExprKind, 1644 /*isType=*/true, 1645 CastTy.getAsOpaquePtr(), 1646 CastRange); 1647 1648 if (OpTok.is(tok::kw_alignof) || OpTok.is(tok::kw__Alignof)) 1649 Diag(OpTok, diag::ext_alignof_expr) << OpTok.getIdentifierInfo(); 1650 1651 // If we get here, the operand to the sizeof/alignof was an expresion. 1652 if (!Operand.isInvalid()) 1653 Operand = Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(), 1654 ExprKind, 1655 /*isType=*/false, 1656 Operand.release(), 1657 CastRange); 1658 return Operand; 1659} 1660 1661/// ParseBuiltinPrimaryExpression 1662/// 1663/// \verbatim 1664/// primary-expression: [C99 6.5.1] 1665/// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' 1666/// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' 1667/// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' 1668/// assign-expr ')' 1669/// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' 1670/// [OCL] '__builtin_astype' '(' assignment-expression ',' type-name ')' 1671/// 1672/// [GNU] offsetof-member-designator: 1673/// [GNU] identifier 1674/// [GNU] offsetof-member-designator '.' identifier 1675/// [GNU] offsetof-member-designator '[' expression ']' 1676/// \endverbatim 1677ExprResult Parser::ParseBuiltinPrimaryExpression() { 1678 ExprResult Res; 1679 const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo(); 1680 1681 tok::TokenKind T = Tok.getKind(); 1682 SourceLocation StartLoc = ConsumeToken(); // Eat the builtin identifier. 1683 1684 // All of these start with an open paren. 1685 if (Tok.isNot(tok::l_paren)) 1686 return ExprError(Diag(Tok, diag::err_expected_after) << BuiltinII 1687 << tok::l_paren); 1688 1689 BalancedDelimiterTracker PT(*this, tok::l_paren); 1690 PT.consumeOpen(); 1691 1692 // TODO: Build AST. 1693 1694 switch (T) { 1695 default: llvm_unreachable("Not a builtin primary expression!"); 1696 case tok::kw___builtin_va_arg: { 1697 ExprResult Expr(ParseAssignmentExpression()); 1698 1699 if (ExpectAndConsume(tok::comma)) { 1700 SkipUntil(tok::r_paren, StopAtSemi); 1701 Expr = ExprError(); 1702 } 1703 1704 TypeResult Ty = ParseTypeName(); 1705 1706 if (Tok.isNot(tok::r_paren)) { 1707 Diag(Tok, diag::err_expected) << tok::r_paren; 1708 Expr = ExprError(); 1709 } 1710 1711 if (Expr.isInvalid() || Ty.isInvalid()) 1712 Res = ExprError(); 1713 else 1714 Res = Actions.ActOnVAArg(StartLoc, Expr.take(), Ty.get(), ConsumeParen()); 1715 break; 1716 } 1717 case tok::kw___builtin_offsetof: { 1718 SourceLocation TypeLoc = Tok.getLocation(); 1719 TypeResult Ty = ParseTypeName(); 1720 if (Ty.isInvalid()) { 1721 SkipUntil(tok::r_paren, StopAtSemi); 1722 return ExprError(); 1723 } 1724 1725 if (ExpectAndConsume(tok::comma)) { 1726 SkipUntil(tok::r_paren, StopAtSemi); 1727 return ExprError(); 1728 } 1729 1730 // We must have at least one identifier here. 1731 if (Tok.isNot(tok::identifier)) { 1732 Diag(Tok, diag::err_expected) << tok::identifier; 1733 SkipUntil(tok::r_paren, StopAtSemi); 1734 return ExprError(); 1735 } 1736 1737 // Keep track of the various subcomponents we see. 1738 SmallVector<Sema::OffsetOfComponent, 4> Comps; 1739 1740 Comps.push_back(Sema::OffsetOfComponent()); 1741 Comps.back().isBrackets = false; 1742 Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); 1743 Comps.back().LocStart = Comps.back().LocEnd = ConsumeToken(); 1744 1745 // FIXME: This loop leaks the index expressions on error. 1746 while (1) { 1747 if (Tok.is(tok::period)) { 1748 // offsetof-member-designator: offsetof-member-designator '.' identifier 1749 Comps.push_back(Sema::OffsetOfComponent()); 1750 Comps.back().isBrackets = false; 1751 Comps.back().LocStart = ConsumeToken(); 1752 1753 if (Tok.isNot(tok::identifier)) { 1754 Diag(Tok, diag::err_expected) << tok::identifier; 1755 SkipUntil(tok::r_paren, StopAtSemi); 1756 return ExprError(); 1757 } 1758 Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); 1759 Comps.back().LocEnd = ConsumeToken(); 1760 1761 } else if (Tok.is(tok::l_square)) { 1762 if (CheckProhibitedCXX11Attribute()) 1763 return ExprError(); 1764 1765 // offsetof-member-designator: offsetof-member-design '[' expression ']' 1766 Comps.push_back(Sema::OffsetOfComponent()); 1767 Comps.back().isBrackets = true; 1768 BalancedDelimiterTracker ST(*this, tok::l_square); 1769 ST.consumeOpen(); 1770 Comps.back().LocStart = ST.getOpenLocation(); 1771 Res = ParseExpression(); 1772 if (Res.isInvalid()) { 1773 SkipUntil(tok::r_paren, StopAtSemi); 1774 return Res; 1775 } 1776 Comps.back().U.E = Res.release(); 1777 1778 ST.consumeClose(); 1779 Comps.back().LocEnd = ST.getCloseLocation(); 1780 } else { 1781 if (Tok.isNot(tok::r_paren)) { 1782 PT.consumeClose(); 1783 Res = ExprError(); 1784 } else if (Ty.isInvalid()) { 1785 Res = ExprError(); 1786 } else { 1787 PT.consumeClose(); 1788 Res = Actions.ActOnBuiltinOffsetOf(getCurScope(), StartLoc, TypeLoc, 1789 Ty.get(), &Comps[0], Comps.size(), 1790 PT.getCloseLocation()); 1791 } 1792 break; 1793 } 1794 } 1795 break; 1796 } 1797 case tok::kw___builtin_choose_expr: { 1798 ExprResult Cond(ParseAssignmentExpression()); 1799 if (Cond.isInvalid()) { 1800 SkipUntil(tok::r_paren, StopAtSemi); 1801 return Cond; 1802 } 1803 if (ExpectAndConsume(tok::comma)) { 1804 SkipUntil(tok::r_paren, StopAtSemi); 1805 return ExprError(); 1806 } 1807 1808 ExprResult Expr1(ParseAssignmentExpression()); 1809 if (Expr1.isInvalid()) { 1810 SkipUntil(tok::r_paren, StopAtSemi); 1811 return Expr1; 1812 } 1813 if (ExpectAndConsume(tok::comma)) { 1814 SkipUntil(tok::r_paren, StopAtSemi); 1815 return ExprError(); 1816 } 1817 1818 ExprResult Expr2(ParseAssignmentExpression()); 1819 if (Expr2.isInvalid()) { 1820 SkipUntil(tok::r_paren, StopAtSemi); 1821 return Expr2; 1822 } 1823 if (Tok.isNot(tok::r_paren)) { 1824 Diag(Tok, diag::err_expected) << tok::r_paren; 1825 return ExprError(); 1826 } 1827 Res = Actions.ActOnChooseExpr(StartLoc, Cond.take(), Expr1.take(), 1828 Expr2.take(), ConsumeParen()); 1829 break; 1830 } 1831 case tok::kw___builtin_astype: { 1832 // The first argument is an expression to be converted, followed by a comma. 1833 ExprResult Expr(ParseAssignmentExpression()); 1834 if (Expr.isInvalid()) { 1835 SkipUntil(tok::r_paren, StopAtSemi); 1836 return ExprError(); 1837 } 1838 1839 if (ExpectAndConsume(tok::comma)) { 1840 SkipUntil(tok::r_paren, StopAtSemi); 1841 return ExprError(); 1842 } 1843 1844 // Second argument is the type to bitcast to. 1845 TypeResult DestTy = ParseTypeName(); 1846 if (DestTy.isInvalid()) 1847 return ExprError(); 1848 1849 // Attempt to consume the r-paren. 1850 if (Tok.isNot(tok::r_paren)) { 1851 Diag(Tok, diag::err_expected) << tok::r_paren; 1852 SkipUntil(tok::r_paren, StopAtSemi); 1853 return ExprError(); 1854 } 1855 1856 Res = Actions.ActOnAsTypeExpr(Expr.take(), DestTy.get(), StartLoc, 1857 ConsumeParen()); 1858 break; 1859 } 1860 case tok::kw___builtin_convertvector: { 1861 // The first argument is an expression to be converted, followed by a comma. 1862 ExprResult Expr(ParseAssignmentExpression()); 1863 if (Expr.isInvalid()) { 1864 SkipUntil(tok::r_paren, StopAtSemi); 1865 return ExprError(); 1866 } 1867 1868 if (ExpectAndConsume(tok::comma)) { 1869 SkipUntil(tok::r_paren, StopAtSemi); 1870 return ExprError(); 1871 } 1872 1873 // Second argument is the type to bitcast to. 1874 TypeResult DestTy = ParseTypeName(); 1875 if (DestTy.isInvalid()) 1876 return ExprError(); 1877 1878 // Attempt to consume the r-paren. 1879 if (Tok.isNot(tok::r_paren)) { 1880 Diag(Tok, diag::err_expected) << tok::r_paren; 1881 SkipUntil(tok::r_paren, StopAtSemi); 1882 return ExprError(); 1883 } 1884 1885 Res = Actions.ActOnConvertVectorExpr(Expr.take(), DestTy.get(), StartLoc, 1886 ConsumeParen()); 1887 break; 1888 } 1889 } 1890 1891 if (Res.isInvalid()) 1892 return ExprError(); 1893 1894 // These can be followed by postfix-expr pieces because they are 1895 // primary-expressions. 1896 return ParsePostfixExpressionSuffix(Res.take()); 1897} 1898 1899/// ParseParenExpression - This parses the unit that starts with a '(' token, 1900/// based on what is allowed by ExprType. The actual thing parsed is returned 1901/// in ExprType. If stopIfCastExpr is true, it will only return the parsed type, 1902/// not the parsed cast-expression. 1903/// 1904/// \verbatim 1905/// primary-expression: [C99 6.5.1] 1906/// '(' expression ')' 1907/// [GNU] '(' compound-statement ')' (if !ParenExprOnly) 1908/// postfix-expression: [C99 6.5.2] 1909/// '(' type-name ')' '{' initializer-list '}' 1910/// '(' type-name ')' '{' initializer-list ',' '}' 1911/// cast-expression: [C99 6.5.4] 1912/// '(' type-name ')' cast-expression 1913/// [ARC] bridged-cast-expression 1914/// 1915/// [ARC] bridged-cast-expression: 1916/// (__bridge type-name) cast-expression 1917/// (__bridge_transfer type-name) cast-expression 1918/// (__bridge_retained type-name) cast-expression 1919/// \endverbatim 1920ExprResult 1921Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr, 1922 bool isTypeCast, ParsedType &CastTy, 1923 SourceLocation &RParenLoc) { 1924 assert(Tok.is(tok::l_paren) && "Not a paren expr!"); 1925 ColonProtectionRAIIObject ColonProtection(*this, false); 1926 BalancedDelimiterTracker T(*this, tok::l_paren); 1927 if (T.consumeOpen()) 1928 return ExprError(); 1929 SourceLocation OpenLoc = T.getOpenLocation(); 1930 1931 ExprResult Result(true); 1932 bool isAmbiguousTypeId; 1933 CastTy = ParsedType(); 1934 1935 if (Tok.is(tok::code_completion)) { 1936 Actions.CodeCompleteOrdinaryName(getCurScope(), 1937 ExprType >= CompoundLiteral? Sema::PCC_ParenthesizedExpression 1938 : Sema::PCC_Expression); 1939 cutOffParsing(); 1940 return ExprError(); 1941 } 1942 1943 // Diagnose use of bridge casts in non-arc mode. 1944 bool BridgeCast = (getLangOpts().ObjC2 && 1945 (Tok.is(tok::kw___bridge) || 1946 Tok.is(tok::kw___bridge_transfer) || 1947 Tok.is(tok::kw___bridge_retained) || 1948 Tok.is(tok::kw___bridge_retain))); 1949 if (BridgeCast && !getLangOpts().ObjCAutoRefCount) { 1950 if (!TryConsumeToken(tok::kw___bridge)) { 1951 StringRef BridgeCastName = Tok.getName(); 1952 SourceLocation BridgeKeywordLoc = ConsumeToken(); 1953 if (!PP.getSourceManager().isInSystemHeader(BridgeKeywordLoc)) 1954 Diag(BridgeKeywordLoc, diag::warn_arc_bridge_cast_nonarc) 1955 << BridgeCastName 1956 << FixItHint::CreateReplacement(BridgeKeywordLoc, ""); 1957 } 1958 BridgeCast = false; 1959 } 1960 1961 // None of these cases should fall through with an invalid Result 1962 // unless they've already reported an error. 1963 if (ExprType >= CompoundStmt && Tok.is(tok::l_brace)) { 1964 Diag(Tok, diag::ext_gnu_statement_expr); 1965 Actions.ActOnStartStmtExpr(); 1966 1967 StmtResult Stmt(ParseCompoundStatement(true)); 1968 ExprType = CompoundStmt; 1969 1970 // If the substmt parsed correctly, build the AST node. 1971 if (!Stmt.isInvalid()) { 1972 Result = Actions.ActOnStmtExpr(OpenLoc, Stmt.take(), Tok.getLocation()); 1973 } else { 1974 Actions.ActOnStmtExprError(); 1975 } 1976 } else if (ExprType >= CompoundLiteral && BridgeCast) { 1977 tok::TokenKind tokenKind = Tok.getKind(); 1978 SourceLocation BridgeKeywordLoc = ConsumeToken(); 1979 1980 // Parse an Objective-C ARC ownership cast expression. 1981 ObjCBridgeCastKind Kind; 1982 if (tokenKind == tok::kw___bridge) 1983 Kind = OBC_Bridge; 1984 else if (tokenKind == tok::kw___bridge_transfer) 1985 Kind = OBC_BridgeTransfer; 1986 else if (tokenKind == tok::kw___bridge_retained) 1987 Kind = OBC_BridgeRetained; 1988 else { 1989 // As a hopefully temporary workaround, allow __bridge_retain as 1990 // a synonym for __bridge_retained, but only in system headers. 1991 assert(tokenKind == tok::kw___bridge_retain); 1992 Kind = OBC_BridgeRetained; 1993 if (!PP.getSourceManager().isInSystemHeader(BridgeKeywordLoc)) 1994 Diag(BridgeKeywordLoc, diag::err_arc_bridge_retain) 1995 << FixItHint::CreateReplacement(BridgeKeywordLoc, 1996 "__bridge_retained"); 1997 } 1998 1999 TypeResult Ty = ParseTypeName(); 2000 T.consumeClose(); 2001 ColonProtection.restore(); 2002 RParenLoc = T.getCloseLocation(); 2003 ExprResult SubExpr = ParseCastExpression(/*isUnaryExpression=*/false); 2004 2005 if (Ty.isInvalid() || SubExpr.isInvalid()) 2006 return ExprError(); 2007 2008 return Actions.ActOnObjCBridgedCast(getCurScope(), OpenLoc, Kind, 2009 BridgeKeywordLoc, Ty.get(), 2010 RParenLoc, SubExpr.get()); 2011 } else if (ExprType >= CompoundLiteral && 2012 isTypeIdInParens(isAmbiguousTypeId)) { 2013 2014 // Otherwise, this is a compound literal expression or cast expression. 2015 2016 // In C++, if the type-id is ambiguous we disambiguate based on context. 2017 // If stopIfCastExpr is true the context is a typeof/sizeof/alignof 2018 // in which case we should treat it as type-id. 2019 // if stopIfCastExpr is false, we need to determine the context past the 2020 // parens, so we defer to ParseCXXAmbiguousParenExpression for that. 2021 if (isAmbiguousTypeId && !stopIfCastExpr) { 2022 ExprResult res = ParseCXXAmbiguousParenExpression(ExprType, CastTy, T, 2023 ColonProtection); 2024 RParenLoc = T.getCloseLocation(); 2025 return res; 2026 } 2027 2028 // Parse the type declarator. 2029 DeclSpec DS(AttrFactory); 2030 ParseSpecifierQualifierList(DS); 2031 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 2032 ParseDeclarator(DeclaratorInfo); 2033 2034 // If our type is followed by an identifier and either ':' or ']', then 2035 // this is probably an Objective-C message send where the leading '[' is 2036 // missing. Recover as if that were the case. 2037 if (!DeclaratorInfo.isInvalidType() && Tok.is(tok::identifier) && 2038 !InMessageExpression && getLangOpts().ObjC1 && 2039 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) { 2040 TypeResult Ty; 2041 { 2042 InMessageExpressionRAIIObject InMessage(*this, false); 2043 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 2044 } 2045 Result = ParseObjCMessageExpressionBody(SourceLocation(), 2046 SourceLocation(), 2047 Ty.get(), nullptr); 2048 } else { 2049 // Match the ')'. 2050 T.consumeClose(); 2051 ColonProtection.restore(); 2052 RParenLoc = T.getCloseLocation(); 2053 if (Tok.is(tok::l_brace)) { 2054 ExprType = CompoundLiteral; 2055 TypeResult Ty; 2056 { 2057 InMessageExpressionRAIIObject InMessage(*this, false); 2058 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 2059 } 2060 return ParseCompoundLiteralExpression(Ty.get(), OpenLoc, RParenLoc); 2061 } 2062 2063 if (ExprType == CastExpr) { 2064 // We parsed '(' type-name ')' and the thing after it wasn't a '{'. 2065 2066 if (DeclaratorInfo.isInvalidType()) 2067 return ExprError(); 2068 2069 // Note that this doesn't parse the subsequent cast-expression, it just 2070 // returns the parsed type to the callee. 2071 if (stopIfCastExpr) { 2072 TypeResult Ty; 2073 { 2074 InMessageExpressionRAIIObject InMessage(*this, false); 2075 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 2076 } 2077 CastTy = Ty.get(); 2078 return ExprResult(); 2079 } 2080 2081 // Reject the cast of super idiom in ObjC. 2082 if (Tok.is(tok::identifier) && getLangOpts().ObjC1 && 2083 Tok.getIdentifierInfo() == Ident_super && 2084 getCurScope()->isInObjcMethodScope() && 2085 GetLookAheadToken(1).isNot(tok::period)) { 2086 Diag(Tok.getLocation(), diag::err_illegal_super_cast) 2087 << SourceRange(OpenLoc, RParenLoc); 2088 return ExprError(); 2089 } 2090 2091 // Parse the cast-expression that follows it next. 2092 // TODO: For cast expression with CastTy. 2093 Result = ParseCastExpression(/*isUnaryExpression=*/false, 2094 /*isAddressOfOperand=*/false, 2095 /*isTypeCast=*/IsTypeCast); 2096 if (!Result.isInvalid()) { 2097 Result = Actions.ActOnCastExpr(getCurScope(), OpenLoc, 2098 DeclaratorInfo, CastTy, 2099 RParenLoc, Result.take()); 2100 } 2101 return Result; 2102 } 2103 2104 Diag(Tok, diag::err_expected_lbrace_in_compound_literal); 2105 return ExprError(); 2106 } 2107 } else if (isTypeCast) { 2108 // Parse the expression-list. 2109 InMessageExpressionRAIIObject InMessage(*this, false); 2110 2111 ExprVector ArgExprs; 2112 CommaLocsTy CommaLocs; 2113 2114 if (!ParseSimpleExpressionList(ArgExprs, CommaLocs)) { 2115 ExprType = SimpleExpr; 2116 Result = Actions.ActOnParenListExpr(OpenLoc, Tok.getLocation(), 2117 ArgExprs); 2118 } 2119 } else { 2120 InMessageExpressionRAIIObject InMessage(*this, false); 2121 2122 Result = ParseExpression(MaybeTypeCast); 2123 ExprType = SimpleExpr; 2124 2125 // Don't build a paren expression unless we actually match a ')'. 2126 if (!Result.isInvalid() && Tok.is(tok::r_paren)) 2127 Result = 2128 Actions.ActOnParenExpr(OpenLoc, Tok.getLocation(), Result.take()); 2129 } 2130 2131 // Match the ')'. 2132 if (Result.isInvalid()) { 2133 SkipUntil(tok::r_paren, StopAtSemi); 2134 return ExprError(); 2135 } 2136 2137 T.consumeClose(); 2138 RParenLoc = T.getCloseLocation(); 2139 return Result; 2140} 2141 2142/// ParseCompoundLiteralExpression - We have parsed the parenthesized type-name 2143/// and we are at the left brace. 2144/// 2145/// \verbatim 2146/// postfix-expression: [C99 6.5.2] 2147/// '(' type-name ')' '{' initializer-list '}' 2148/// '(' type-name ')' '{' initializer-list ',' '}' 2149/// \endverbatim 2150ExprResult 2151Parser::ParseCompoundLiteralExpression(ParsedType Ty, 2152 SourceLocation LParenLoc, 2153 SourceLocation RParenLoc) { 2154 assert(Tok.is(tok::l_brace) && "Not a compound literal!"); 2155 if (!getLangOpts().C99) // Compound literals don't exist in C90. 2156 Diag(LParenLoc, diag::ext_c99_compound_literal); 2157 ExprResult Result = ParseInitializer(); 2158 if (!Result.isInvalid() && Ty) 2159 return Actions.ActOnCompoundLiteral(LParenLoc, Ty, RParenLoc, Result.take()); 2160 return Result; 2161} 2162 2163/// ParseStringLiteralExpression - This handles the various token types that 2164/// form string literals, and also handles string concatenation [C99 5.1.1.2, 2165/// translation phase #6]. 2166/// 2167/// \verbatim 2168/// primary-expression: [C99 6.5.1] 2169/// string-literal 2170/// \verbatim 2171ExprResult Parser::ParseStringLiteralExpression(bool AllowUserDefinedLiteral) { 2172 assert(isTokenStringLiteral() && "Not a string literal!"); 2173 2174 // String concat. Note that keywords like __func__ and __FUNCTION__ are not 2175 // considered to be strings for concatenation purposes. 2176 SmallVector<Token, 4> StringToks; 2177 2178 do { 2179 StringToks.push_back(Tok); 2180 ConsumeStringToken(); 2181 } while (isTokenStringLiteral()); 2182 2183 // Pass the set of string tokens, ready for concatenation, to the actions. 2184 return Actions.ActOnStringLiteral(&StringToks[0], StringToks.size(), 2185 AllowUserDefinedLiteral ? getCurScope() 2186 : nullptr); 2187} 2188 2189/// ParseGenericSelectionExpression - Parse a C11 generic-selection 2190/// [C11 6.5.1.1]. 2191/// 2192/// \verbatim 2193/// generic-selection: 2194/// _Generic ( assignment-expression , generic-assoc-list ) 2195/// generic-assoc-list: 2196/// generic-association 2197/// generic-assoc-list , generic-association 2198/// generic-association: 2199/// type-name : assignment-expression 2200/// default : assignment-expression 2201/// \endverbatim 2202ExprResult Parser::ParseGenericSelectionExpression() { 2203 assert(Tok.is(tok::kw__Generic) && "_Generic keyword expected"); 2204 SourceLocation KeyLoc = ConsumeToken(); 2205 2206 if (!getLangOpts().C11) 2207 Diag(KeyLoc, diag::ext_c11_generic_selection); 2208 2209 BalancedDelimiterTracker T(*this, tok::l_paren); 2210 if (T.expectAndConsume()) 2211 return ExprError(); 2212 2213 ExprResult ControllingExpr; 2214 { 2215 // C11 6.5.1.1p3 "The controlling expression of a generic selection is 2216 // not evaluated." 2217 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated); 2218 ControllingExpr = ParseAssignmentExpression(); 2219 if (ControllingExpr.isInvalid()) { 2220 SkipUntil(tok::r_paren, StopAtSemi); 2221 return ExprError(); 2222 } 2223 } 2224 2225 if (ExpectAndConsume(tok::comma)) { 2226 SkipUntil(tok::r_paren, StopAtSemi); 2227 return ExprError(); 2228 } 2229 2230 SourceLocation DefaultLoc; 2231 TypeVector Types; 2232 ExprVector Exprs; 2233 do { 2234 ParsedType Ty; 2235 if (Tok.is(tok::kw_default)) { 2236 // C11 6.5.1.1p2 "A generic selection shall have no more than one default 2237 // generic association." 2238 if (!DefaultLoc.isInvalid()) { 2239 Diag(Tok, diag::err_duplicate_default_assoc); 2240 Diag(DefaultLoc, diag::note_previous_default_assoc); 2241 SkipUntil(tok::r_paren, StopAtSemi); 2242 return ExprError(); 2243 } 2244 DefaultLoc = ConsumeToken(); 2245 Ty = ParsedType(); 2246 } else { 2247 ColonProtectionRAIIObject X(*this); 2248 TypeResult TR = ParseTypeName(); 2249 if (TR.isInvalid()) { 2250 SkipUntil(tok::r_paren, StopAtSemi); 2251 return ExprError(); 2252 } 2253 Ty = TR.release(); 2254 } 2255 Types.push_back(Ty); 2256 2257 if (ExpectAndConsume(tok::colon)) { 2258 SkipUntil(tok::r_paren, StopAtSemi); 2259 return ExprError(); 2260 } 2261 2262 // FIXME: These expressions should be parsed in a potentially potentially 2263 // evaluated context. 2264 ExprResult ER(ParseAssignmentExpression()); 2265 if (ER.isInvalid()) { 2266 SkipUntil(tok::r_paren, StopAtSemi); 2267 return ExprError(); 2268 } 2269 Exprs.push_back(ER.release()); 2270 } while (TryConsumeToken(tok::comma)); 2271 2272 T.consumeClose(); 2273 if (T.getCloseLocation().isInvalid()) 2274 return ExprError(); 2275 2276 return Actions.ActOnGenericSelectionExpr(KeyLoc, DefaultLoc, 2277 T.getCloseLocation(), 2278 ControllingExpr.release(), 2279 Types, Exprs); 2280} 2281 2282/// ParseExpressionList - Used for C/C++ (argument-)expression-list. 2283/// 2284/// \verbatim 2285/// argument-expression-list: 2286/// assignment-expression 2287/// argument-expression-list , assignment-expression 2288/// 2289/// [C++] expression-list: 2290/// [C++] assignment-expression 2291/// [C++] expression-list , assignment-expression 2292/// 2293/// [C++0x] expression-list: 2294/// [C++0x] initializer-list 2295/// 2296/// [C++0x] initializer-list 2297/// [C++0x] initializer-clause ...[opt] 2298/// [C++0x] initializer-list , initializer-clause ...[opt] 2299/// 2300/// [C++0x] initializer-clause: 2301/// [C++0x] assignment-expression 2302/// [C++0x] braced-init-list 2303/// \endverbatim 2304bool Parser::ParseExpressionList(SmallVectorImpl<Expr*> &Exprs, 2305 SmallVectorImpl<SourceLocation> &CommaLocs, 2306 void (Sema::*Completer)(Scope *S, 2307 Expr *Data, 2308 ArrayRef<Expr *> Args), 2309 Expr *Data) { 2310 while (1) { 2311 if (Tok.is(tok::code_completion)) { 2312 if (Completer) 2313 (Actions.*Completer)(getCurScope(), Data, Exprs); 2314 else 2315 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); 2316 cutOffParsing(); 2317 return true; 2318 } 2319 2320 ExprResult Expr; 2321 if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) { 2322 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); 2323 Expr = ParseBraceInitializer(); 2324 } else 2325 Expr = ParseAssignmentExpression(); 2326 2327 if (Tok.is(tok::ellipsis)) 2328 Expr = Actions.ActOnPackExpansion(Expr.get(), ConsumeToken()); 2329 if (Expr.isInvalid()) 2330 return true; 2331 2332 Exprs.push_back(Expr.release()); 2333 2334 if (Tok.isNot(tok::comma)) 2335 return false; 2336 // Move to the next argument, remember where the comma was. 2337 CommaLocs.push_back(ConsumeToken()); 2338 } 2339} 2340 2341/// ParseSimpleExpressionList - A simple comma-separated list of expressions, 2342/// used for misc language extensions. 2343/// 2344/// \verbatim 2345/// simple-expression-list: 2346/// assignment-expression 2347/// simple-expression-list , assignment-expression 2348/// \endverbatim 2349bool 2350Parser::ParseSimpleExpressionList(SmallVectorImpl<Expr*> &Exprs, 2351 SmallVectorImpl<SourceLocation> &CommaLocs) { 2352 while (1) { 2353 ExprResult Expr = ParseAssignmentExpression(); 2354 if (Expr.isInvalid()) 2355 return true; 2356 2357 Exprs.push_back(Expr.release()); 2358 2359 if (Tok.isNot(tok::comma)) 2360 return false; 2361 2362 // Move to the next argument, remember where the comma was. 2363 CommaLocs.push_back(ConsumeToken()); 2364 } 2365} 2366 2367/// ParseBlockId - Parse a block-id, which roughly looks like int (int x). 2368/// 2369/// \verbatim 2370/// [clang] block-id: 2371/// [clang] specifier-qualifier-list block-declarator 2372/// \endverbatim 2373void Parser::ParseBlockId(SourceLocation CaretLoc) { 2374 if (Tok.is(tok::code_completion)) { 2375 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Type); 2376 return cutOffParsing(); 2377 } 2378 2379 // Parse the specifier-qualifier-list piece. 2380 DeclSpec DS(AttrFactory); 2381 ParseSpecifierQualifierList(DS); 2382 2383 // Parse the block-declarator. 2384 Declarator DeclaratorInfo(DS, Declarator::BlockLiteralContext); 2385 ParseDeclarator(DeclaratorInfo); 2386 2387 // We do this for: ^ __attribute__((noreturn)) {, as DS has the attributes. 2388 DeclaratorInfo.takeAttributes(DS.getAttributes(), SourceLocation()); 2389 2390 MaybeParseGNUAttributes(DeclaratorInfo); 2391 2392 // Inform sema that we are starting a block. 2393 Actions.ActOnBlockArguments(CaretLoc, DeclaratorInfo, getCurScope()); 2394} 2395 2396/// ParseBlockLiteralExpression - Parse a block literal, which roughly looks 2397/// like ^(int x){ return x+1; } 2398/// 2399/// \verbatim 2400/// block-literal: 2401/// [clang] '^' block-args[opt] compound-statement 2402/// [clang] '^' block-id compound-statement 2403/// [clang] block-args: 2404/// [clang] '(' parameter-list ')' 2405/// \endverbatim 2406ExprResult Parser::ParseBlockLiteralExpression() { 2407 assert(Tok.is(tok::caret) && "block literal starts with ^"); 2408 SourceLocation CaretLoc = ConsumeToken(); 2409 2410 PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), CaretLoc, 2411 "block literal parsing"); 2412 2413 // Enter a scope to hold everything within the block. This includes the 2414 // argument decls, decls within the compound expression, etc. This also 2415 // allows determining whether a variable reference inside the block is 2416 // within or outside of the block. 2417 ParseScope BlockScope(this, Scope::BlockScope | Scope::FnScope | 2418 Scope::DeclScope); 2419 2420 // Inform sema that we are starting a block. 2421 Actions.ActOnBlockStart(CaretLoc, getCurScope()); 2422 2423 // Parse the return type if present. 2424 DeclSpec DS(AttrFactory); 2425 Declarator ParamInfo(DS, Declarator::BlockLiteralContext); 2426 // FIXME: Since the return type isn't actually parsed, it can't be used to 2427 // fill ParamInfo with an initial valid range, so do it manually. 2428 ParamInfo.SetSourceRange(SourceRange(Tok.getLocation(), Tok.getLocation())); 2429 2430 // If this block has arguments, parse them. There is no ambiguity here with 2431 // the expression case, because the expression case requires a parameter list. 2432 if (Tok.is(tok::l_paren)) { 2433 ParseParenDeclarator(ParamInfo); 2434 // Parse the pieces after the identifier as if we had "int(...)". 2435 // SetIdentifier sets the source range end, but in this case we're past 2436 // that location. 2437 SourceLocation Tmp = ParamInfo.getSourceRange().getEnd(); 2438 ParamInfo.SetIdentifier(nullptr, CaretLoc); 2439 ParamInfo.SetRangeEnd(Tmp); 2440 if (ParamInfo.isInvalidType()) { 2441 // If there was an error parsing the arguments, they may have 2442 // tried to use ^(x+y) which requires an argument list. Just 2443 // skip the whole block literal. 2444 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2445 return ExprError(); 2446 } 2447 2448 MaybeParseGNUAttributes(ParamInfo); 2449 2450 // Inform sema that we are starting a block. 2451 Actions.ActOnBlockArguments(CaretLoc, ParamInfo, getCurScope()); 2452 } else if (!Tok.is(tok::l_brace)) { 2453 ParseBlockId(CaretLoc); 2454 } else { 2455 // Otherwise, pretend we saw (void). 2456 ParsedAttributes attrs(AttrFactory); 2457 SourceLocation NoLoc; 2458 ParamInfo.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/true, 2459 /*IsAmbiguous=*/false, 2460 /*RParenLoc=*/NoLoc, 2461 /*ArgInfo=*/nullptr, 2462 /*NumArgs=*/0, 2463 /*EllipsisLoc=*/NoLoc, 2464 /*RParenLoc=*/NoLoc, 2465 /*TypeQuals=*/0, 2466 /*RefQualifierIsLvalueRef=*/true, 2467 /*RefQualifierLoc=*/NoLoc, 2468 /*ConstQualifierLoc=*/NoLoc, 2469 /*VolatileQualifierLoc=*/NoLoc, 2470 /*MutableLoc=*/NoLoc, 2471 EST_None, 2472 /*ESpecLoc=*/NoLoc, 2473 /*Exceptions=*/nullptr, 2474 /*ExceptionRanges=*/nullptr, 2475 /*NumExceptions=*/0, 2476 /*NoexceptExpr=*/nullptr, 2477 CaretLoc, CaretLoc, 2478 ParamInfo), 2479 attrs, CaretLoc); 2480 2481 MaybeParseGNUAttributes(ParamInfo); 2482 2483 // Inform sema that we are starting a block. 2484 Actions.ActOnBlockArguments(CaretLoc, ParamInfo, getCurScope()); 2485 } 2486 2487 2488 ExprResult Result(true); 2489 if (!Tok.is(tok::l_brace)) { 2490 // Saw something like: ^expr 2491 Diag(Tok, diag::err_expected_expression); 2492 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2493 return ExprError(); 2494 } 2495 2496 StmtResult Stmt(ParseCompoundStatementBody()); 2497 BlockScope.Exit(); 2498 if (!Stmt.isInvalid()) 2499 Result = Actions.ActOnBlockStmtExpr(CaretLoc, Stmt.take(), getCurScope()); 2500 else 2501 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2502 return Result; 2503} 2504 2505/// ParseObjCBoolLiteral - This handles the objective-c Boolean literals. 2506/// 2507/// '__objc_yes' 2508/// '__objc_no' 2509ExprResult Parser::ParseObjCBoolLiteral() { 2510 tok::TokenKind Kind = Tok.getKind(); 2511 return Actions.ActOnObjCBoolLiteral(ConsumeToken(), Kind); 2512} 2513