Parser.cpp revision ab197baec16bacade82325fb274cf6b992ac5d8a
1//===--- Parser.cpp - C Language Family Parser ----------------------------===// 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// This file implements the Parser interfaces. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Parse/Parser.h" 15#include "clang/Parse/ParseDiagnostic.h" 16#include "clang/Parse/DeclSpec.h" 17#include "clang/Parse/Scope.h" 18#include "ExtensionRAIIObject.h" 19#include "ParsePragma.h" 20using namespace clang; 21 22Parser::Parser(Preprocessor &pp, Action &actions) 23 : PP(pp), Actions(actions), Diags(PP.getDiagnostics()) { 24 Tok.setKind(tok::eof); 25 CurScope = 0; 26 NumCachedScopes = 0; 27 ParenCount = BracketCount = BraceCount = 0; 28 ObjCImpDecl = 0; 29 30 // Add #pragma handlers. These are removed and destroyed in the 31 // destructor. 32 PackHandler = 33 new PragmaPackHandler(&PP.getIdentifierTable().get("pack"), actions); 34 PP.AddPragmaHandler(0, PackHandler); 35 36 // Instantiate a LexedMethodsForTopClass for all the non-nested classes. 37 PushTopClassStack(); 38} 39 40/// Out-of-line virtual destructor to provide home for Action class. 41ActionBase::~ActionBase() {} 42 43/// Out-of-line virtual destructor to provide home for Action class. 44Action::~Action() {} 45 46// Defined out-of-line here because of dependecy on AttributeList 47Action::DeclTy *Action::ActOnUsingDirective(Scope *CurScope, 48 SourceLocation UsingLoc, 49 SourceLocation NamespcLoc, 50 const CXXScopeSpec &SS, 51 SourceLocation IdentLoc, 52 IdentifierInfo *NamespcName, 53 AttributeList *AttrList) { 54 55 // FIXME: Parser seems to assume that Action::ActOn* takes ownership over 56 // passed AttributeList, however other actions don't free it, is it 57 // temporary state or bug? 58 delete AttrList; 59 return 0; 60} 61 62DiagnosticBuilder Parser::Diag(SourceLocation Loc, unsigned DiagID) { 63 return Diags.Report(FullSourceLoc(Loc,PP.getSourceManager()), DiagID); 64} 65 66DiagnosticBuilder Parser::Diag(const Token &Tok, unsigned DiagID) { 67 return Diag(Tok.getLocation(), DiagID); 68} 69 70/// MatchRHSPunctuation - For punctuation with a LHS and RHS (e.g. '['/']'), 71/// this helper function matches and consumes the specified RHS token if 72/// present. If not present, it emits the specified diagnostic indicating 73/// that the parser failed to match the RHS of the token at LHSLoc. LHSName 74/// should be the name of the unmatched LHS token. 75SourceLocation Parser::MatchRHSPunctuation(tok::TokenKind RHSTok, 76 SourceLocation LHSLoc) { 77 78 if (Tok.is(RHSTok)) 79 return ConsumeAnyToken(); 80 81 SourceLocation R = Tok.getLocation(); 82 const char *LHSName = "unknown"; 83 diag::kind DID = diag::err_parse_error; 84 switch (RHSTok) { 85 default: break; 86 case tok::r_paren : LHSName = "("; DID = diag::err_expected_rparen; break; 87 case tok::r_brace : LHSName = "{"; DID = diag::err_expected_rbrace; break; 88 case tok::r_square: LHSName = "["; DID = diag::err_expected_rsquare; break; 89 case tok::greater: LHSName = "<"; DID = diag::err_expected_greater; break; 90 } 91 Diag(Tok, DID); 92 Diag(LHSLoc, diag::note_matching) << LHSName; 93 SkipUntil(RHSTok); 94 return R; 95} 96 97/// ExpectAndConsume - The parser expects that 'ExpectedTok' is next in the 98/// input. If so, it is consumed and false is returned. 99/// 100/// If the input is malformed, this emits the specified diagnostic. Next, if 101/// SkipToTok is specified, it calls SkipUntil(SkipToTok). Finally, true is 102/// returned. 103bool Parser::ExpectAndConsume(tok::TokenKind ExpectedTok, unsigned DiagID, 104 const char *Msg, tok::TokenKind SkipToTok) { 105 if (Tok.is(ExpectedTok)) { 106 ConsumeAnyToken(); 107 return false; 108 } 109 110 Diag(Tok, DiagID) << Msg; 111 if (SkipToTok != tok::unknown) 112 SkipUntil(SkipToTok); 113 return true; 114} 115 116//===----------------------------------------------------------------------===// 117// Error recovery. 118//===----------------------------------------------------------------------===// 119 120/// SkipUntil - Read tokens until we get to the specified token, then consume 121/// it (unless DontConsume is true). Because we cannot guarantee that the 122/// token will ever occur, this skips to the next token, or to some likely 123/// good stopping point. If StopAtSemi is true, skipping will stop at a ';' 124/// character. 125/// 126/// If SkipUntil finds the specified token, it returns true, otherwise it 127/// returns false. 128bool Parser::SkipUntil(const tok::TokenKind *Toks, unsigned NumToks, 129 bool StopAtSemi, bool DontConsume) { 130 // We always want this function to skip at least one token if the first token 131 // isn't T and if not at EOF. 132 bool isFirstTokenSkipped = true; 133 while (1) { 134 // If we found one of the tokens, stop and return true. 135 for (unsigned i = 0; i != NumToks; ++i) { 136 if (Tok.is(Toks[i])) { 137 if (DontConsume) { 138 // Noop, don't consume the token. 139 } else { 140 ConsumeAnyToken(); 141 } 142 return true; 143 } 144 } 145 146 switch (Tok.getKind()) { 147 case tok::eof: 148 // Ran out of tokens. 149 return false; 150 151 case tok::l_paren: 152 // Recursively skip properly-nested parens. 153 ConsumeParen(); 154 SkipUntil(tok::r_paren, false); 155 break; 156 case tok::l_square: 157 // Recursively skip properly-nested square brackets. 158 ConsumeBracket(); 159 SkipUntil(tok::r_square, false); 160 break; 161 case tok::l_brace: 162 // Recursively skip properly-nested braces. 163 ConsumeBrace(); 164 SkipUntil(tok::r_brace, false); 165 break; 166 167 // Okay, we found a ']' or '}' or ')', which we think should be balanced. 168 // Since the user wasn't looking for this token (if they were, it would 169 // already be handled), this isn't balanced. If there is a LHS token at a 170 // higher level, we will assume that this matches the unbalanced token 171 // and return it. Otherwise, this is a spurious RHS token, which we skip. 172 case tok::r_paren: 173 if (ParenCount && !isFirstTokenSkipped) 174 return false; // Matches something. 175 ConsumeParen(); 176 break; 177 case tok::r_square: 178 if (BracketCount && !isFirstTokenSkipped) 179 return false; // Matches something. 180 ConsumeBracket(); 181 break; 182 case tok::r_brace: 183 if (BraceCount && !isFirstTokenSkipped) 184 return false; // Matches something. 185 ConsumeBrace(); 186 break; 187 188 case tok::string_literal: 189 case tok::wide_string_literal: 190 ConsumeStringToken(); 191 break; 192 case tok::semi: 193 if (StopAtSemi) 194 return false; 195 // FALL THROUGH. 196 default: 197 // Skip this token. 198 ConsumeToken(); 199 break; 200 } 201 isFirstTokenSkipped = false; 202 } 203} 204 205//===----------------------------------------------------------------------===// 206// Scope manipulation 207//===----------------------------------------------------------------------===// 208 209/// EnterScope - Start a new scope. 210void Parser::EnterScope(unsigned ScopeFlags) { 211 if (NumCachedScopes) { 212 Scope *N = ScopeCache[--NumCachedScopes]; 213 N->Init(CurScope, ScopeFlags); 214 CurScope = N; 215 } else { 216 CurScope = new Scope(CurScope, ScopeFlags); 217 } 218} 219 220/// ExitScope - Pop a scope off the scope stack. 221void Parser::ExitScope() { 222 assert(CurScope && "Scope imbalance!"); 223 224 // Inform the actions module that this scope is going away if there are any 225 // decls in it. 226 if (!CurScope->decl_empty()) 227 Actions.ActOnPopScope(Tok.getLocation(), CurScope); 228 229 Scope *OldScope = CurScope; 230 CurScope = OldScope->getParent(); 231 232 if (NumCachedScopes == ScopeCacheSize) 233 delete OldScope; 234 else 235 ScopeCache[NumCachedScopes++] = OldScope; 236} 237 238 239 240 241//===----------------------------------------------------------------------===// 242// C99 6.9: External Definitions. 243//===----------------------------------------------------------------------===// 244 245Parser::~Parser() { 246 // If we still have scopes active, delete the scope tree. 247 delete CurScope; 248 249 // Free the scope cache. 250 for (unsigned i = 0, e = NumCachedScopes; i != e; ++i) 251 delete ScopeCache[i]; 252 253 // Remove the pragma handlers we installed. 254 PP.RemovePragmaHandler(0, PackHandler); 255 delete PackHandler; 256} 257 258/// Initialize - Warm up the parser. 259/// 260void Parser::Initialize() { 261 // Prime the lexer look-ahead. 262 ConsumeToken(); 263 264 // Create the translation unit scope. Install it as the current scope. 265 assert(CurScope == 0 && "A scope is already active?"); 266 EnterScope(Scope::DeclScope); 267 Actions.ActOnTranslationUnitScope(Tok.getLocation(), CurScope); 268 269 if (Tok.is(tok::eof) && 270 !getLang().CPlusPlus) // Empty source file is an extension in C 271 Diag(Tok, diag::ext_empty_source_file); 272 273 // Initialization for Objective-C context sensitive keywords recognition. 274 // Referenced in Parser::ParseObjCTypeQualifierList. 275 if (getLang().ObjC1) { 276 ObjCTypeQuals[objc_in] = &PP.getIdentifierTable().get("in"); 277 ObjCTypeQuals[objc_out] = &PP.getIdentifierTable().get("out"); 278 ObjCTypeQuals[objc_inout] = &PP.getIdentifierTable().get("inout"); 279 ObjCTypeQuals[objc_oneway] = &PP.getIdentifierTable().get("oneway"); 280 ObjCTypeQuals[objc_bycopy] = &PP.getIdentifierTable().get("bycopy"); 281 ObjCTypeQuals[objc_byref] = &PP.getIdentifierTable().get("byref"); 282 } 283 284 Ident_super = &PP.getIdentifierTable().get("super"); 285} 286 287/// ParseTopLevelDecl - Parse one top-level declaration, return whatever the 288/// action tells us to. This returns true if the EOF was encountered. 289bool Parser::ParseTopLevelDecl(DeclTy*& Result) { 290 Result = 0; 291 if (Tok.is(tok::eof)) { 292 Actions.ActOnEndOfTranslationUnit(); 293 return true; 294 } 295 296 Result = ParseExternalDeclaration(); 297 return false; 298} 299 300/// ParseTranslationUnit: 301/// translation-unit: [C99 6.9] 302/// external-declaration 303/// translation-unit external-declaration 304void Parser::ParseTranslationUnit() { 305 Initialize(); 306 307 DeclTy *Res; 308 while (!ParseTopLevelDecl(Res)) 309 /*parse them all*/; 310 311 ExitScope(); 312 assert(CurScope == 0 && "Scope imbalance!"); 313} 314 315/// ParseExternalDeclaration: 316/// 317/// external-declaration: [C99 6.9], declaration: [C++ dcl.dcl] 318/// function-definition 319/// declaration 320/// [EXT] ';' 321/// [GNU] asm-definition 322/// [GNU] __extension__ external-declaration 323/// [OBJC] objc-class-definition 324/// [OBJC] objc-class-declaration 325/// [OBJC] objc-alias-declaration 326/// [OBJC] objc-protocol-definition 327/// [OBJC] objc-method-definition 328/// [OBJC] @end 329/// [C++] linkage-specification 330/// [GNU] asm-definition: 331/// simple-asm-expr ';' 332/// 333Parser::DeclTy *Parser::ParseExternalDeclaration() { 334 switch (Tok.getKind()) { 335 case tok::semi: 336 Diag(Tok, diag::ext_top_level_semi); 337 ConsumeToken(); 338 // TODO: Invoke action for top-level semicolon. 339 return 0; 340 case tok::r_brace: 341 Diag(Tok, diag::err_expected_external_declaration); 342 ConsumeBrace(); 343 return 0; 344 case tok::eof: 345 Diag(Tok, diag::err_expected_external_declaration); 346 return 0; 347 case tok::kw___extension__: { 348 // __extension__ silences extension warnings in the subexpression. 349 ExtensionRAIIObject O(Diags); // Use RAII to do this. 350 ConsumeToken(); 351 return ParseExternalDeclaration(); 352 } 353 case tok::kw_asm: { 354 OwningExprResult Result(ParseSimpleAsm()); 355 356 ExpectAndConsume(tok::semi, diag::err_expected_semi_after, 357 "top-level asm block"); 358 359 if (!Result.isInvalid()) 360 return Actions.ActOnFileScopeAsmDecl(Tok.getLocation(), move(Result)); 361 return 0; 362 } 363 case tok::at: 364 // @ is not a legal token unless objc is enabled, no need to check. 365 return ParseObjCAtDirectives(); 366 case tok::minus: 367 case tok::plus: 368 if (getLang().ObjC1) 369 return ParseObjCMethodDefinition(); 370 else { 371 Diag(Tok, diag::err_expected_external_declaration); 372 ConsumeToken(); 373 } 374 return 0; 375 case tok::kw_using: 376 case tok::kw_namespace: 377 case tok::kw_typedef: 378 case tok::kw_template: 379 case tok::kw_export: // As in 'export template' 380 // A function definition cannot start with a these keywords. 381 return ParseDeclaration(Declarator::FileContext); 382 default: 383 // We can't tell whether this is a function-definition or declaration yet. 384 return ParseDeclarationOrFunctionDefinition(); 385 } 386} 387 388/// ParseDeclarationOrFunctionDefinition - Parse either a function-definition or 389/// a declaration. We can't tell which we have until we read up to the 390/// compound-statement in function-definition. TemplateParams, if 391/// non-NULL, provides the template parameters when we're parsing a 392/// C++ template-declaration. 393/// 394/// function-definition: [C99 6.9.1] 395/// decl-specs declarator declaration-list[opt] compound-statement 396/// [C90] function-definition: [C99 6.7.1] - implicit int result 397/// [C90] decl-specs[opt] declarator declaration-list[opt] compound-statement 398/// 399/// declaration: [C99 6.7] 400/// declaration-specifiers init-declarator-list[opt] ';' 401/// [!C99] init-declarator-list ';' [TODO: warn in c99 mode] 402/// [OMP] threadprivate-directive [TODO] 403/// 404Parser::DeclTy * 405Parser::ParseDeclarationOrFunctionDefinition( 406 TemplateParameterLists *TemplateParams) { 407 // Parse the common declaration-specifiers piece. 408 DeclSpec DS; 409 ParseDeclarationSpecifiers(DS, TemplateParams); 410 411 // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };" 412 // declaration-specifiers init-declarator-list[opt] ';' 413 if (Tok.is(tok::semi)) { 414 ConsumeToken(); 415 return Actions.ParsedFreeStandingDeclSpec(CurScope, DS); 416 } 417 418 // ObjC2 allows prefix attributes on class interfaces and protocols. 419 // FIXME: This still needs better diagnostics. We should only accept 420 // attributes here, no types, etc. 421 if (getLang().ObjC2 && Tok.is(tok::at)) { 422 SourceLocation AtLoc = ConsumeToken(); // the "@" 423 if (!Tok.isObjCAtKeyword(tok::objc_interface) && 424 !Tok.isObjCAtKeyword(tok::objc_protocol)) { 425 Diag(Tok, diag::err_objc_unexpected_attr); 426 SkipUntil(tok::semi); // FIXME: better skip? 427 return 0; 428 } 429 const char *PrevSpec = 0; 430 if (DS.SetTypeSpecType(DeclSpec::TST_unspecified, AtLoc, PrevSpec)) 431 Diag(AtLoc, diag::err_invalid_decl_spec_combination) << PrevSpec; 432 if (Tok.isObjCAtKeyword(tok::objc_protocol)) 433 return ParseObjCAtProtocolDeclaration(AtLoc, DS.getAttributes()); 434 return ParseObjCAtInterfaceDeclaration(AtLoc, DS.getAttributes()); 435 } 436 437 // If the declspec consisted only of 'extern' and we have a string 438 // literal following it, this must be a C++ linkage specifier like 439 // 'extern "C"'. 440 if (Tok.is(tok::string_literal) && getLang().CPlusPlus && 441 DS.getStorageClassSpec() == DeclSpec::SCS_extern && 442 DS.getParsedSpecifiers() == DeclSpec::PQ_StorageClassSpecifier) 443 return ParseLinkage(Declarator::FileContext); 444 445 // Parse the first declarator. 446 Declarator DeclaratorInfo(DS, Declarator::FileContext); 447 ParseDeclarator(DeclaratorInfo); 448 // Error parsing the declarator? 449 if (!DeclaratorInfo.hasName()) { 450 // If so, skip until the semi-colon or a }. 451 SkipUntil(tok::r_brace, true, true); 452 if (Tok.is(tok::semi)) 453 ConsumeToken(); 454 return 0; 455 } 456 457 // If the declarator is the start of a function definition, handle it. 458 if (Tok.is(tok::equal) || // int X()= -> not a function def 459 Tok.is(tok::comma) || // int X(), -> not a function def 460 Tok.is(tok::semi) || // int X(); -> not a function def 461 Tok.is(tok::kw_asm) || // int X() __asm__ -> not a function def 462 Tok.is(tok::kw___attribute) || // int X() __attr__ -> not a function def 463 (getLang().CPlusPlus && 464 Tok.is(tok::l_paren)) ) { // int X(0) -> not a function def [C++] 465 // FALL THROUGH. 466 } else if (DeclaratorInfo.isFunctionDeclarator() && 467 (Tok.is(tok::l_brace) || // int X() {} 468 ( !getLang().CPlusPlus && 469 isDeclarationSpecifier() ))) { // int X(f) int f; {} 470 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) { 471 Diag(Tok, diag::err_function_declared_typedef); 472 473 if (Tok.is(tok::l_brace)) { 474 // This recovery skips the entire function body. It would be nice 475 // to simply call ParseFunctionDefinition() below, however Sema 476 // assumes the declarator represents a function, not a typedef. 477 ConsumeBrace(); 478 SkipUntil(tok::r_brace, true); 479 } else { 480 SkipUntil(tok::semi); 481 } 482 return 0; 483 } 484 return ParseFunctionDefinition(DeclaratorInfo); 485 } else { 486 if (DeclaratorInfo.isFunctionDeclarator()) 487 Diag(Tok, diag::err_expected_fn_body); 488 else 489 Diag(Tok, diag::err_expected_after_declarator); 490 SkipUntil(tok::semi); 491 return 0; 492 } 493 494 // Parse the init-declarator-list for a normal declaration. 495 return ParseInitDeclaratorListAfterFirstDeclarator(DeclaratorInfo); 496} 497 498/// ParseFunctionDefinition - We parsed and verified that the specified 499/// Declarator is well formed. If this is a K&R-style function, read the 500/// parameters declaration-list, then start the compound-statement. 501/// 502/// function-definition: [C99 6.9.1] 503/// decl-specs declarator declaration-list[opt] compound-statement 504/// [C90] function-definition: [C99 6.7.1] - implicit int result 505/// [C90] decl-specs[opt] declarator declaration-list[opt] compound-statement 506/// [C++] function-definition: [C++ 8.4] 507/// decl-specifier-seq[opt] declarator ctor-initializer[opt] function-body 508/// [C++] function-definition: [C++ 8.4] 509/// decl-specifier-seq[opt] declarator function-try-block [TODO] 510/// 511Parser::DeclTy *Parser::ParseFunctionDefinition(Declarator &D) { 512 const DeclaratorChunk &FnTypeInfo = D.getTypeObject(0); 513 assert(FnTypeInfo.Kind == DeclaratorChunk::Function && 514 "This isn't a function declarator!"); 515 const DeclaratorChunk::FunctionTypeInfo &FTI = FnTypeInfo.Fun; 516 517 // If this is C90 and the declspecs were completely missing, fudge in an 518 // implicit int. We do this here because this is the only place where 519 // declaration-specifiers are completely optional in the grammar. 520 if (getLang().ImplicitInt && D.getDeclSpec().getParsedSpecifiers() == 0) { 521 const char *PrevSpec; 522 D.getMutableDeclSpec().SetTypeSpecType(DeclSpec::TST_int, 523 D.getIdentifierLoc(), 524 PrevSpec); 525 D.SetRangeBegin(D.getDeclSpec().getSourceRange().getBegin()); 526 } 527 528 // If this declaration was formed with a K&R-style identifier list for the 529 // arguments, parse declarations for all of the args next. 530 // int foo(a,b) int a; float b; {} 531 if (!FTI.hasPrototype && FTI.NumArgs != 0) 532 ParseKNRParamDeclarations(D); 533 534 // We should have either an opening brace or, in a C++ constructor, 535 // we may have a colon. 536 // FIXME: In C++, we might also find the 'try' keyword. 537 if (Tok.isNot(tok::l_brace) && Tok.isNot(tok::colon)) { 538 Diag(Tok, diag::err_expected_fn_body); 539 540 // Skip over garbage, until we get to '{'. Don't eat the '{'. 541 SkipUntil(tok::l_brace, true, true); 542 543 // If we didn't find the '{', bail out. 544 if (Tok.isNot(tok::l_brace)) 545 return 0; 546 } 547 548 // Enter a scope for the function body. 549 ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope); 550 551 // Tell the actions module that we have entered a function definition with the 552 // specified Declarator for the function. 553 DeclTy *Res = Actions.ActOnStartOfFunctionDef(CurScope, D); 554 555 // If we have a colon, then we're probably parsing a C++ 556 // ctor-initializer. 557 if (Tok.is(tok::colon)) 558 ParseConstructorInitializer(Res); 559 560 SourceLocation BraceLoc = Tok.getLocation(); 561 return ParseFunctionStatementBody(Res, BraceLoc, BraceLoc); 562} 563 564/// ParseKNRParamDeclarations - Parse 'declaration-list[opt]' which provides 565/// types for a function with a K&R-style identifier list for arguments. 566void Parser::ParseKNRParamDeclarations(Declarator &D) { 567 // We know that the top-level of this declarator is a function. 568 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 569 570 // Enter function-declaration scope, limiting any declarators to the 571 // function prototype scope, including parameter declarators. 572 ParseScope PrototypeScope(this, Scope::FunctionPrototypeScope|Scope::DeclScope); 573 574 // Read all the argument declarations. 575 while (isDeclarationSpecifier()) { 576 SourceLocation DSStart = Tok.getLocation(); 577 578 // Parse the common declaration-specifiers piece. 579 DeclSpec DS; 580 ParseDeclarationSpecifiers(DS); 581 582 // C99 6.9.1p6: 'each declaration in the declaration list shall have at 583 // least one declarator'. 584 // NOTE: GCC just makes this an ext-warn. It's not clear what it does with 585 // the declarations though. It's trivial to ignore them, really hard to do 586 // anything else with them. 587 if (Tok.is(tok::semi)) { 588 Diag(DSStart, diag::err_declaration_does_not_declare_param); 589 ConsumeToken(); 590 continue; 591 } 592 593 // C99 6.9.1p6: Declarations shall contain no storage-class specifiers other 594 // than register. 595 if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 596 DS.getStorageClassSpec() != DeclSpec::SCS_register) { 597 Diag(DS.getStorageClassSpecLoc(), 598 diag::err_invalid_storage_class_in_func_decl); 599 DS.ClearStorageClassSpecs(); 600 } 601 if (DS.isThreadSpecified()) { 602 Diag(DS.getThreadSpecLoc(), 603 diag::err_invalid_storage_class_in_func_decl); 604 DS.ClearStorageClassSpecs(); 605 } 606 607 // Parse the first declarator attached to this declspec. 608 Declarator ParmDeclarator(DS, Declarator::KNRTypeListContext); 609 ParseDeclarator(ParmDeclarator); 610 611 // Handle the full declarator list. 612 while (1) { 613 DeclTy *AttrList; 614 // If attributes are present, parse them. 615 if (Tok.is(tok::kw___attribute)) 616 // FIXME: attach attributes too. 617 AttrList = ParseAttributes(); 618 619 // Ask the actions module to compute the type for this declarator. 620 Action::DeclTy *Param = 621 Actions.ActOnParamDeclarator(CurScope, ParmDeclarator); 622 623 if (Param && 624 // A missing identifier has already been diagnosed. 625 ParmDeclarator.getIdentifier()) { 626 627 // Scan the argument list looking for the correct param to apply this 628 // type. 629 for (unsigned i = 0; ; ++i) { 630 // C99 6.9.1p6: those declarators shall declare only identifiers from 631 // the identifier list. 632 if (i == FTI.NumArgs) { 633 Diag(ParmDeclarator.getIdentifierLoc(), diag::err_no_matching_param) 634 << ParmDeclarator.getIdentifier(); 635 break; 636 } 637 638 if (FTI.ArgInfo[i].Ident == ParmDeclarator.getIdentifier()) { 639 // Reject redefinitions of parameters. 640 if (FTI.ArgInfo[i].Param) { 641 Diag(ParmDeclarator.getIdentifierLoc(), 642 diag::err_param_redefinition) 643 << ParmDeclarator.getIdentifier(); 644 } else { 645 FTI.ArgInfo[i].Param = Param; 646 } 647 break; 648 } 649 } 650 } 651 652 // If we don't have a comma, it is either the end of the list (a ';') or 653 // an error, bail out. 654 if (Tok.isNot(tok::comma)) 655 break; 656 657 // Consume the comma. 658 ConsumeToken(); 659 660 // Parse the next declarator. 661 ParmDeclarator.clear(); 662 ParseDeclarator(ParmDeclarator); 663 } 664 665 if (Tok.is(tok::semi)) { 666 ConsumeToken(); 667 } else { 668 Diag(Tok, diag::err_parse_error); 669 // Skip to end of block or statement 670 SkipUntil(tok::semi, true); 671 if (Tok.is(tok::semi)) 672 ConsumeToken(); 673 } 674 } 675 676 // The actions module must verify that all arguments were declared. 677 Actions.ActOnFinishKNRParamDeclarations(CurScope, D); 678} 679 680 681/// ParseAsmStringLiteral - This is just a normal string-literal, but is not 682/// allowed to be a wide string, and is not subject to character translation. 683/// 684/// [GNU] asm-string-literal: 685/// string-literal 686/// 687Parser::OwningExprResult Parser::ParseAsmStringLiteral() { 688 if (!isTokenStringLiteral()) { 689 Diag(Tok, diag::err_expected_string_literal); 690 return ExprError(); 691 } 692 693 OwningExprResult Res(ParseStringLiteralExpression()); 694 if (Res.isInvalid()) return move(Res); 695 696 // TODO: Diagnose: wide string literal in 'asm' 697 698 return move(Res); 699} 700 701/// ParseSimpleAsm 702/// 703/// [GNU] simple-asm-expr: 704/// 'asm' '(' asm-string-literal ')' 705/// 706Parser::OwningExprResult Parser::ParseSimpleAsm(SourceLocation *EndLoc) { 707 assert(Tok.is(tok::kw_asm) && "Not an asm!"); 708 SourceLocation Loc = ConsumeToken(); 709 710 if (Tok.isNot(tok::l_paren)) { 711 Diag(Tok, diag::err_expected_lparen_after) << "asm"; 712 return ExprError(); 713 } 714 715 Loc = ConsumeParen(); 716 717 OwningExprResult Result(ParseAsmStringLiteral()); 718 719 if (Result.isInvalid()) { 720 SkipUntil(tok::r_paren, true, true); 721 if (EndLoc) 722 *EndLoc = Tok.getLocation(); 723 ConsumeAnyToken(); 724 } else { 725 Loc = MatchRHSPunctuation(tok::r_paren, Loc); 726 if (EndLoc) 727 *EndLoc = Loc; 728 } 729 730 return move(Result); 731} 732 733/// TryAnnotateTypeOrScopeToken - If the current token position is on a 734/// typename (possibly qualified in C++) or a C++ scope specifier not followed 735/// by a typename, TryAnnotateTypeOrScopeToken will replace one or more tokens 736/// with a single annotation token representing the typename or C++ scope 737/// respectively. 738/// This simplifies handling of C++ scope specifiers and allows efficient 739/// backtracking without the need to re-parse and resolve nested-names and 740/// typenames. 741/// It will mainly be called when we expect to treat identifiers as typenames 742/// (if they are typenames). For example, in C we do not expect identifiers 743/// inside expressions to be treated as typenames so it will not be called 744/// for expressions in C. 745/// The benefit for C/ObjC is that a typename will be annotated and 746/// Actions.getTypeName will not be needed to be called again (e.g. getTypeName 747/// will not be called twice, once to check whether we have a declaration 748/// specifier, and another one to get the actual type inside 749/// ParseDeclarationSpecifiers). 750/// 751/// This returns true if the token was annotated. 752/// 753/// Note that this routine emits an error if you call it with ::new or ::delete 754/// as the current tokens, so only call it in contexts where these are invalid. 755bool Parser::TryAnnotateTypeOrScopeToken() { 756 assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon)) && 757 "Cannot be a type or scope token!"); 758 759 // FIXME: Implement template-ids 760 CXXScopeSpec SS; 761 if (getLang().CPlusPlus) 762 ParseOptionalCXXScopeSpecifier(SS); 763 764 if (Tok.is(tok::identifier)) { 765 // Determine whether the identifier is a type name. 766 if (TypeTy *Ty = Actions.getTypeName(*Tok.getIdentifierInfo(), 767 Tok.getLocation(), CurScope, &SS)) { 768 // This is a typename. Replace the current token in-place with an 769 // annotation type token. 770 Tok.setKind(tok::annot_typename); 771 Tok.setAnnotationValue(Ty); 772 Tok.setAnnotationEndLoc(Tok.getLocation()); 773 if (SS.isNotEmpty()) // it was a C++ qualified type name. 774 Tok.setLocation(SS.getBeginLoc()); 775 776 // In case the tokens were cached, have Preprocessor replace 777 // them with the annotation token. 778 PP.AnnotateCachedTokens(Tok); 779 return true; 780 } else if (!getLang().CPlusPlus) { 781 // If we're in C, we can't have :: tokens at all (the lexer won't return 782 // them). If the identifier is not a type, then it can't be scope either, 783 // just early exit. 784 return false; 785 } 786 787 // If this is a template-id, annotate the template-id token. 788 if (NextToken().is(tok::less)) 789 if (DeclTy *Template = 790 Actions.isTemplateName(*Tok.getIdentifierInfo(), CurScope, &SS)) 791 AnnotateTemplateIdToken(Template, &SS); 792 793 // We either have an identifier that is not a type name or we have 794 // just created a template-id that might be a type name. Both 795 // cases will be handled below. 796 } 797 798 // FIXME: check for a template-id token here, and look it up if it 799 // names a type. 800 801 if (SS.isEmpty()) 802 return false; 803 804 // A C++ scope specifier that isn't followed by a typename. 805 // Push the current token back into the token stream (or revert it if it is 806 // cached) and use an annotation scope token for current token. 807 if (PP.isBacktrackEnabled()) 808 PP.RevertCachedTokens(1); 809 else 810 PP.EnterToken(Tok); 811 Tok.setKind(tok::annot_cxxscope); 812 Tok.setAnnotationValue(SS.getScopeRep()); 813 Tok.setAnnotationRange(SS.getRange()); 814 815 // In case the tokens were cached, have Preprocessor replace them with the 816 // annotation token. 817 PP.AnnotateCachedTokens(Tok); 818 return true; 819} 820 821/// TryAnnotateScopeToken - Like TryAnnotateTypeOrScopeToken but only 822/// annotates C++ scope specifiers. This returns true if the token was 823/// annotated. 824/// 825/// Note that this routine emits an error if you call it with ::new or ::delete 826/// as the current tokens, so only call it in contexts where these are invalid. 827bool Parser::TryAnnotateCXXScopeToken() { 828 assert(getLang().CPlusPlus && 829 "Call sites of this function should be guarded by checking for C++"); 830 assert((Tok.is(tok::identifier) || Tok.is(tok::coloncolon)) && 831 "Cannot be a type or scope token!"); 832 833 CXXScopeSpec SS; 834 if (!ParseOptionalCXXScopeSpecifier(SS)) 835 return false; 836 837 // Push the current token back into the token stream (or revert it if it is 838 // cached) and use an annotation scope token for current token. 839 if (PP.isBacktrackEnabled()) 840 PP.RevertCachedTokens(1); 841 else 842 PP.EnterToken(Tok); 843 Tok.setKind(tok::annot_cxxscope); 844 Tok.setAnnotationValue(SS.getScopeRep()); 845 Tok.setAnnotationRange(SS.getRange()); 846 847 // In case the tokens were cached, have Preprocessor replace them with the 848 // annotation token. 849 PP.AnnotateCachedTokens(Tok); 850 return true; 851} 852