1//===--- ParseTemplate.cpp - Template 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// This file implements parsing of C++ templates. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Parse/Parser.h" 15#include "RAIIObjectsForParser.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/DeclTemplate.h" 18#include "clang/Parse/ParseDiagnostic.h" 19#include "clang/Sema/DeclSpec.h" 20#include "clang/Sema/ParsedTemplate.h" 21#include "clang/Sema/Scope.h" 22using namespace clang; 23 24/// \brief Parse a template declaration, explicit instantiation, or 25/// explicit specialization. 26Decl * 27Parser::ParseDeclarationStartingWithTemplate(unsigned Context, 28 SourceLocation &DeclEnd, 29 AccessSpecifier AS, 30 AttributeList *AccessAttrs) { 31 ObjCDeclContextSwitch ObjCDC(*this); 32 33 if (Tok.is(tok::kw_template) && NextToken().isNot(tok::less)) { 34 return ParseExplicitInstantiation(Context, 35 SourceLocation(), ConsumeToken(), 36 DeclEnd, AS); 37 } 38 return ParseTemplateDeclarationOrSpecialization(Context, DeclEnd, AS, 39 AccessAttrs); 40} 41 42 43 44/// \brief Parse a template declaration or an explicit specialization. 45/// 46/// Template declarations include one or more template parameter lists 47/// and either the function or class template declaration. Explicit 48/// specializations contain one or more 'template < >' prefixes 49/// followed by a (possibly templated) declaration. Since the 50/// syntactic form of both features is nearly identical, we parse all 51/// of the template headers together and let semantic analysis sort 52/// the declarations from the explicit specializations. 53/// 54/// template-declaration: [C++ temp] 55/// 'export'[opt] 'template' '<' template-parameter-list '>' declaration 56/// 57/// explicit-specialization: [ C++ temp.expl.spec] 58/// 'template' '<' '>' declaration 59Decl * 60Parser::ParseTemplateDeclarationOrSpecialization(unsigned Context, 61 SourceLocation &DeclEnd, 62 AccessSpecifier AS, 63 AttributeList *AccessAttrs) { 64 assert((Tok.is(tok::kw_export) || Tok.is(tok::kw_template)) && 65 "Token does not start a template declaration."); 66 67 // Enter template-parameter scope. 68 ParseScope TemplateParmScope(this, Scope::TemplateParamScope); 69 70 // Tell the action that names should be checked in the context of 71 // the declaration to come. 72 ParsingDeclRAIIObject 73 ParsingTemplateParams(*this, ParsingDeclRAIIObject::NoParent); 74 75 // Parse multiple levels of template headers within this template 76 // parameter scope, e.g., 77 // 78 // template<typename T> 79 // template<typename U> 80 // class A<T>::B { ... }; 81 // 82 // We parse multiple levels non-recursively so that we can build a 83 // single data structure containing all of the template parameter 84 // lists to easily differentiate between the case above and: 85 // 86 // template<typename T> 87 // class A { 88 // template<typename U> class B; 89 // }; 90 // 91 // In the first case, the action for declaring A<T>::B receives 92 // both template parameter lists. In the second case, the action for 93 // defining A<T>::B receives just the inner template parameter list 94 // (and retrieves the outer template parameter list from its 95 // context). 96 bool isSpecialization = true; 97 bool LastParamListWasEmpty = false; 98 TemplateParameterLists ParamLists; 99 TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth); 100 101 do { 102 // Consume the 'export', if any. 103 SourceLocation ExportLoc; 104 if (Tok.is(tok::kw_export)) { 105 ExportLoc = ConsumeToken(); 106 } 107 108 // Consume the 'template', which should be here. 109 SourceLocation TemplateLoc; 110 if (Tok.is(tok::kw_template)) { 111 TemplateLoc = ConsumeToken(); 112 } else { 113 Diag(Tok.getLocation(), diag::err_expected_template); 114 return 0; 115 } 116 117 // Parse the '<' template-parameter-list '>' 118 SourceLocation LAngleLoc, RAngleLoc; 119 SmallVector<Decl*, 4> TemplateParams; 120 if (ParseTemplateParameters(CurTemplateDepthTracker.getDepth(), 121 TemplateParams, LAngleLoc, RAngleLoc)) { 122 // Skip until the semi-colon or a }. 123 SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch); 124 if (Tok.is(tok::semi)) 125 ConsumeToken(); 126 return 0; 127 } 128 129 ParamLists.push_back( 130 Actions.ActOnTemplateParameterList(CurTemplateDepthTracker.getDepth(), 131 ExportLoc, 132 TemplateLoc, LAngleLoc, 133 TemplateParams.data(), 134 TemplateParams.size(), RAngleLoc)); 135 136 if (!TemplateParams.empty()) { 137 isSpecialization = false; 138 ++CurTemplateDepthTracker; 139 } else { 140 LastParamListWasEmpty = true; 141 } 142 } while (Tok.is(tok::kw_export) || Tok.is(tok::kw_template)); 143 144 // Parse the actual template declaration. 145 return ParseSingleDeclarationAfterTemplate(Context, 146 ParsedTemplateInfo(&ParamLists, 147 isSpecialization, 148 LastParamListWasEmpty), 149 ParsingTemplateParams, 150 DeclEnd, AS, AccessAttrs); 151} 152 153/// \brief Parse a single declaration that declares a template, 154/// template specialization, or explicit instantiation of a template. 155/// 156/// \param DeclEnd will receive the source location of the last token 157/// within this declaration. 158/// 159/// \param AS the access specifier associated with this 160/// declaration. Will be AS_none for namespace-scope declarations. 161/// 162/// \returns the new declaration. 163Decl * 164Parser::ParseSingleDeclarationAfterTemplate( 165 unsigned Context, 166 const ParsedTemplateInfo &TemplateInfo, 167 ParsingDeclRAIIObject &DiagsFromTParams, 168 SourceLocation &DeclEnd, 169 AccessSpecifier AS, 170 AttributeList *AccessAttrs) { 171 assert(TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate && 172 "Template information required"); 173 174 if (Context == Declarator::MemberContext) { 175 // We are parsing a member template. 176 ParseCXXClassMemberDeclaration(AS, AccessAttrs, TemplateInfo, 177 &DiagsFromTParams); 178 return 0; 179 } 180 181 ParsedAttributesWithRange prefixAttrs(AttrFactory); 182 MaybeParseCXX11Attributes(prefixAttrs); 183 184 if (Tok.is(tok::kw_using)) 185 return ParseUsingDirectiveOrDeclaration(Context, TemplateInfo, DeclEnd, 186 prefixAttrs); 187 188 // Parse the declaration specifiers, stealing any diagnostics from 189 // the template parameters. 190 ParsingDeclSpec DS(*this, &DiagsFromTParams); 191 192 ParseDeclarationSpecifiers(DS, TemplateInfo, AS, 193 getDeclSpecContextFromDeclaratorContext(Context)); 194 195 if (Tok.is(tok::semi)) { 196 ProhibitAttributes(prefixAttrs); 197 DeclEnd = ConsumeToken(); 198 Decl *Decl = Actions.ParsedFreeStandingDeclSpec( 199 getCurScope(), AS, DS, 200 TemplateInfo.TemplateParams ? *TemplateInfo.TemplateParams 201 : MultiTemplateParamsArg(), 202 TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation); 203 DS.complete(Decl); 204 return Decl; 205 } 206 207 // Move the attributes from the prefix into the DS. 208 if (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation) 209 ProhibitAttributes(prefixAttrs); 210 else 211 DS.takeAttributesFrom(prefixAttrs); 212 213 // Parse the declarator. 214 ParsingDeclarator DeclaratorInfo(*this, DS, (Declarator::TheContext)Context); 215 ParseDeclarator(DeclaratorInfo); 216 // Error parsing the declarator? 217 if (!DeclaratorInfo.hasName()) { 218 // If so, skip until the semi-colon or a }. 219 SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch); 220 if (Tok.is(tok::semi)) 221 ConsumeToken(); 222 return 0; 223 } 224 225 LateParsedAttrList LateParsedAttrs(true); 226 if (DeclaratorInfo.isFunctionDeclarator()) 227 MaybeParseGNUAttributes(DeclaratorInfo, &LateParsedAttrs); 228 229 if (DeclaratorInfo.isFunctionDeclarator() && 230 isStartOfFunctionDefinition(DeclaratorInfo)) { 231 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) { 232 // Recover by ignoring the 'typedef'. This was probably supposed to be 233 // the 'typename' keyword, which we should have already suggested adding 234 // if it's appropriate. 235 Diag(DS.getStorageClassSpecLoc(), diag::err_function_declared_typedef) 236 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc()); 237 DS.ClearStorageClassSpecs(); 238 } 239 240 if (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation) { 241 if (DeclaratorInfo.getName().getKind() != UnqualifiedId::IK_TemplateId) { 242 // If the declarator-id is not a template-id, issue a diagnostic and 243 // recover by ignoring the 'template' keyword. 244 Diag(Tok, diag::err_template_defn_explicit_instantiation) << 0; 245 return ParseFunctionDefinition(DeclaratorInfo, ParsedTemplateInfo(), 246 &LateParsedAttrs); 247 } else { 248 SourceLocation LAngleLoc 249 = PP.getLocForEndOfToken(TemplateInfo.TemplateLoc); 250 Diag(DeclaratorInfo.getIdentifierLoc(), 251 diag::err_explicit_instantiation_with_definition) 252 << SourceRange(TemplateInfo.TemplateLoc) 253 << FixItHint::CreateInsertion(LAngleLoc, "<>"); 254 255 // Recover as if it were an explicit specialization. 256 TemplateParameterLists FakedParamLists; 257 FakedParamLists.push_back(Actions.ActOnTemplateParameterList( 258 0, SourceLocation(), TemplateInfo.TemplateLoc, LAngleLoc, 0, 0, 259 LAngleLoc)); 260 261 return ParseFunctionDefinition( 262 DeclaratorInfo, ParsedTemplateInfo(&FakedParamLists, 263 /*isSpecialization=*/true, 264 /*LastParamListWasEmpty=*/true), 265 &LateParsedAttrs); 266 } 267 } 268 return ParseFunctionDefinition(DeclaratorInfo, TemplateInfo, 269 &LateParsedAttrs); 270 } 271 272 // Parse this declaration. 273 Decl *ThisDecl = ParseDeclarationAfterDeclarator(DeclaratorInfo, 274 TemplateInfo); 275 276 if (Tok.is(tok::comma)) { 277 Diag(Tok, diag::err_multiple_template_declarators) 278 << (int)TemplateInfo.Kind; 279 SkipUntil(tok::semi); 280 return ThisDecl; 281 } 282 283 // Eat the semi colon after the declaration. 284 ExpectAndConsumeSemi(diag::err_expected_semi_declaration); 285 if (LateParsedAttrs.size() > 0) 286 ParseLexedAttributeList(LateParsedAttrs, ThisDecl, true, false); 287 DeclaratorInfo.complete(ThisDecl); 288 return ThisDecl; 289} 290 291/// ParseTemplateParameters - Parses a template-parameter-list enclosed in 292/// angle brackets. Depth is the depth of this template-parameter-list, which 293/// is the number of template headers directly enclosing this template header. 294/// TemplateParams is the current list of template parameters we're building. 295/// The template parameter we parse will be added to this list. LAngleLoc and 296/// RAngleLoc will receive the positions of the '<' and '>', respectively, 297/// that enclose this template parameter list. 298/// 299/// \returns true if an error occurred, false otherwise. 300bool Parser::ParseTemplateParameters(unsigned Depth, 301 SmallVectorImpl<Decl*> &TemplateParams, 302 SourceLocation &LAngleLoc, 303 SourceLocation &RAngleLoc) { 304 // Get the template parameter list. 305 if (!Tok.is(tok::less)) { 306 Diag(Tok.getLocation(), diag::err_expected_less_after) << "template"; 307 return true; 308 } 309 LAngleLoc = ConsumeToken(); 310 311 // Try to parse the template parameter list. 312 bool Failed = false; 313 if (!Tok.is(tok::greater) && !Tok.is(tok::greatergreater)) 314 Failed = ParseTemplateParameterList(Depth, TemplateParams); 315 316 if (Tok.is(tok::greatergreater)) { 317 // No diagnostic required here: a template-parameter-list can only be 318 // followed by a declaration or, for a template template parameter, the 319 // 'class' keyword. Therefore, the second '>' will be diagnosed later. 320 // This matters for elegant diagnosis of: 321 // template<template<typename>> struct S; 322 Tok.setKind(tok::greater); 323 RAngleLoc = Tok.getLocation(); 324 Tok.setLocation(Tok.getLocation().getLocWithOffset(1)); 325 } else if (Tok.is(tok::greater)) 326 RAngleLoc = ConsumeToken(); 327 else if (Failed) { 328 Diag(Tok.getLocation(), diag::err_expected_greater); 329 return true; 330 } 331 return false; 332} 333 334/// ParseTemplateParameterList - Parse a template parameter list. If 335/// the parsing fails badly (i.e., closing bracket was left out), this 336/// will try to put the token stream in a reasonable position (closing 337/// a statement, etc.) and return false. 338/// 339/// template-parameter-list: [C++ temp] 340/// template-parameter 341/// template-parameter-list ',' template-parameter 342bool 343Parser::ParseTemplateParameterList(unsigned Depth, 344 SmallVectorImpl<Decl*> &TemplateParams) { 345 while (1) { 346 if (Decl *TmpParam 347 = ParseTemplateParameter(Depth, TemplateParams.size())) { 348 TemplateParams.push_back(TmpParam); 349 } else { 350 // If we failed to parse a template parameter, skip until we find 351 // a comma or closing brace. 352 SkipUntil(tok::comma, tok::greater, tok::greatergreater, 353 StopAtSemi | StopBeforeMatch); 354 } 355 356 // Did we find a comma or the end of the template parameter list? 357 if (Tok.is(tok::comma)) { 358 ConsumeToken(); 359 } else if (Tok.is(tok::greater) || Tok.is(tok::greatergreater)) { 360 // Don't consume this... that's done by template parser. 361 break; 362 } else { 363 // Somebody probably forgot to close the template. Skip ahead and 364 // try to get out of the expression. This error is currently 365 // subsumed by whatever goes on in ParseTemplateParameter. 366 Diag(Tok.getLocation(), diag::err_expected_comma_greater); 367 SkipUntil(tok::comma, tok::greater, tok::greatergreater, 368 StopAtSemi | StopBeforeMatch); 369 return false; 370 } 371 } 372 return true; 373} 374 375/// \brief Determine whether the parser is at the start of a template 376/// type parameter. 377bool Parser::isStartOfTemplateTypeParameter() { 378 if (Tok.is(tok::kw_class)) { 379 // "class" may be the start of an elaborated-type-specifier or a 380 // type-parameter. Per C++ [temp.param]p3, we prefer the type-parameter. 381 switch (NextToken().getKind()) { 382 case tok::equal: 383 case tok::comma: 384 case tok::greater: 385 case tok::greatergreater: 386 case tok::ellipsis: 387 return true; 388 389 case tok::identifier: 390 // This may be either a type-parameter or an elaborated-type-specifier. 391 // We have to look further. 392 break; 393 394 default: 395 return false; 396 } 397 398 switch (GetLookAheadToken(2).getKind()) { 399 case tok::equal: 400 case tok::comma: 401 case tok::greater: 402 case tok::greatergreater: 403 return true; 404 405 default: 406 return false; 407 } 408 } 409 410 if (Tok.isNot(tok::kw_typename)) 411 return false; 412 413 // C++ [temp.param]p2: 414 // There is no semantic difference between class and typename in a 415 // template-parameter. typename followed by an unqualified-id 416 // names a template type parameter. typename followed by a 417 // qualified-id denotes the type in a non-type 418 // parameter-declaration. 419 Token Next = NextToken(); 420 421 // If we have an identifier, skip over it. 422 if (Next.getKind() == tok::identifier) 423 Next = GetLookAheadToken(2); 424 425 switch (Next.getKind()) { 426 case tok::equal: 427 case tok::comma: 428 case tok::greater: 429 case tok::greatergreater: 430 case tok::ellipsis: 431 return true; 432 433 default: 434 return false; 435 } 436} 437 438/// ParseTemplateParameter - Parse a template-parameter (C++ [temp.param]). 439/// 440/// template-parameter: [C++ temp.param] 441/// type-parameter 442/// parameter-declaration 443/// 444/// type-parameter: (see below) 445/// 'class' ...[opt] identifier[opt] 446/// 'class' identifier[opt] '=' type-id 447/// 'typename' ...[opt] identifier[opt] 448/// 'typename' identifier[opt] '=' type-id 449/// 'template' '<' template-parameter-list '>' 450/// 'class' ...[opt] identifier[opt] 451/// 'template' '<' template-parameter-list '>' 'class' identifier[opt] 452/// = id-expression 453Decl *Parser::ParseTemplateParameter(unsigned Depth, unsigned Position) { 454 if (isStartOfTemplateTypeParameter()) 455 return ParseTypeParameter(Depth, Position); 456 457 if (Tok.is(tok::kw_template)) 458 return ParseTemplateTemplateParameter(Depth, Position); 459 460 // If it's none of the above, then it must be a parameter declaration. 461 // NOTE: This will pick up errors in the closure of the template parameter 462 // list (e.g., template < ; Check here to implement >> style closures. 463 return ParseNonTypeTemplateParameter(Depth, Position); 464} 465 466/// ParseTypeParameter - Parse a template type parameter (C++ [temp.param]). 467/// Other kinds of template parameters are parsed in 468/// ParseTemplateTemplateParameter and ParseNonTypeTemplateParameter. 469/// 470/// type-parameter: [C++ temp.param] 471/// 'class' ...[opt][C++0x] identifier[opt] 472/// 'class' identifier[opt] '=' type-id 473/// 'typename' ...[opt][C++0x] identifier[opt] 474/// 'typename' identifier[opt] '=' type-id 475Decl *Parser::ParseTypeParameter(unsigned Depth, unsigned Position) { 476 assert((Tok.is(tok::kw_class) || Tok.is(tok::kw_typename)) && 477 "A type-parameter starts with 'class' or 'typename'"); 478 479 // Consume the 'class' or 'typename' keyword. 480 bool TypenameKeyword = Tok.is(tok::kw_typename); 481 SourceLocation KeyLoc = ConsumeToken(); 482 483 // Grab the ellipsis (if given). 484 bool Ellipsis = false; 485 SourceLocation EllipsisLoc; 486 if (Tok.is(tok::ellipsis)) { 487 Ellipsis = true; 488 EllipsisLoc = ConsumeToken(); 489 490 Diag(EllipsisLoc, 491 getLangOpts().CPlusPlus11 492 ? diag::warn_cxx98_compat_variadic_templates 493 : diag::ext_variadic_templates); 494 } 495 496 // Grab the template parameter name (if given) 497 SourceLocation NameLoc; 498 IdentifierInfo* ParamName = 0; 499 if (Tok.is(tok::identifier)) { 500 ParamName = Tok.getIdentifierInfo(); 501 NameLoc = ConsumeToken(); 502 } else if (Tok.is(tok::equal) || Tok.is(tok::comma) || 503 Tok.is(tok::greater) || Tok.is(tok::greatergreater)) { 504 // Unnamed template parameter. Don't have to do anything here, just 505 // don't consume this token. 506 } else { 507 Diag(Tok.getLocation(), diag::err_expected_ident); 508 return 0; 509 } 510 511 // Grab a default argument (if available). 512 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before 513 // we introduce the type parameter into the local scope. 514 SourceLocation EqualLoc; 515 ParsedType DefaultArg; 516 if (Tok.is(tok::equal)) { 517 EqualLoc = ConsumeToken(); 518 DefaultArg = ParseTypeName(/*Range=*/0, 519 Declarator::TemplateTypeArgContext).get(); 520 } 521 522 return Actions.ActOnTypeParameter(getCurScope(), TypenameKeyword, Ellipsis, 523 EllipsisLoc, KeyLoc, ParamName, NameLoc, 524 Depth, Position, EqualLoc, DefaultArg); 525} 526 527/// ParseTemplateTemplateParameter - Handle the parsing of template 528/// template parameters. 529/// 530/// type-parameter: [C++ temp.param] 531/// 'template' '<' template-parameter-list '>' 'class' 532/// ...[opt] identifier[opt] 533/// 'template' '<' template-parameter-list '>' 'class' identifier[opt] 534/// = id-expression 535Decl * 536Parser::ParseTemplateTemplateParameter(unsigned Depth, unsigned Position) { 537 assert(Tok.is(tok::kw_template) && "Expected 'template' keyword"); 538 539 // Handle the template <...> part. 540 SourceLocation TemplateLoc = ConsumeToken(); 541 SmallVector<Decl*,8> TemplateParams; 542 SourceLocation LAngleLoc, RAngleLoc; 543 { 544 ParseScope TemplateParmScope(this, Scope::TemplateParamScope); 545 if (ParseTemplateParameters(Depth + 1, TemplateParams, LAngleLoc, 546 RAngleLoc)) { 547 return 0; 548 } 549 } 550 551 // Generate a meaningful error if the user forgot to put class before the 552 // identifier, comma, or greater. Provide a fixit if the identifier, comma, 553 // or greater appear immediately or after 'typename' or 'struct'. In the 554 // latter case, replace the keyword with 'class'. 555 if (!Tok.is(tok::kw_class)) { 556 bool Replace = Tok.is(tok::kw_typename) || Tok.is(tok::kw_struct); 557 const Token& Next = Replace ? NextToken() : Tok; 558 if (Next.is(tok::identifier) || Next.is(tok::comma) || 559 Next.is(tok::greater) || Next.is(tok::greatergreater) || 560 Next.is(tok::ellipsis)) 561 Diag(Tok.getLocation(), diag::err_class_on_template_template_param) 562 << (Replace ? FixItHint::CreateReplacement(Tok.getLocation(), "class") 563 : FixItHint::CreateInsertion(Tok.getLocation(), "class ")); 564 else 565 Diag(Tok.getLocation(), diag::err_class_on_template_template_param); 566 567 if (Replace) 568 ConsumeToken(); 569 } else 570 ConsumeToken(); 571 572 // Parse the ellipsis, if given. 573 SourceLocation EllipsisLoc; 574 if (Tok.is(tok::ellipsis)) { 575 EllipsisLoc = ConsumeToken(); 576 577 Diag(EllipsisLoc, 578 getLangOpts().CPlusPlus11 579 ? diag::warn_cxx98_compat_variadic_templates 580 : diag::ext_variadic_templates); 581 } 582 583 // Get the identifier, if given. 584 SourceLocation NameLoc; 585 IdentifierInfo* ParamName = 0; 586 if (Tok.is(tok::identifier)) { 587 ParamName = Tok.getIdentifierInfo(); 588 NameLoc = ConsumeToken(); 589 } else if (Tok.is(tok::equal) || Tok.is(tok::comma) || 590 Tok.is(tok::greater) || Tok.is(tok::greatergreater)) { 591 // Unnamed template parameter. Don't have to do anything here, just 592 // don't consume this token. 593 } else { 594 Diag(Tok.getLocation(), diag::err_expected_ident); 595 return 0; 596 } 597 598 TemplateParameterList *ParamList = 599 Actions.ActOnTemplateParameterList(Depth, SourceLocation(), 600 TemplateLoc, LAngleLoc, 601 TemplateParams.data(), 602 TemplateParams.size(), 603 RAngleLoc); 604 605 // Grab a default argument (if available). 606 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before 607 // we introduce the template parameter into the local scope. 608 SourceLocation EqualLoc; 609 ParsedTemplateArgument DefaultArg; 610 if (Tok.is(tok::equal)) { 611 EqualLoc = ConsumeToken(); 612 DefaultArg = ParseTemplateTemplateArgument(); 613 if (DefaultArg.isInvalid()) { 614 Diag(Tok.getLocation(), 615 diag::err_default_template_template_parameter_not_template); 616 SkipUntil(tok::comma, tok::greater, tok::greatergreater, 617 StopAtSemi | StopBeforeMatch); 618 } 619 } 620 621 return Actions.ActOnTemplateTemplateParameter(getCurScope(), TemplateLoc, 622 ParamList, EllipsisLoc, 623 ParamName, NameLoc, Depth, 624 Position, EqualLoc, DefaultArg); 625} 626 627/// ParseNonTypeTemplateParameter - Handle the parsing of non-type 628/// template parameters (e.g., in "template<int Size> class array;"). 629/// 630/// template-parameter: 631/// ... 632/// parameter-declaration 633Decl * 634Parser::ParseNonTypeTemplateParameter(unsigned Depth, unsigned Position) { 635 // Parse the declaration-specifiers (i.e., the type). 636 // FIXME: The type should probably be restricted in some way... Not all 637 // declarators (parts of declarators?) are accepted for parameters. 638 DeclSpec DS(AttrFactory); 639 ParseDeclarationSpecifiers(DS); 640 641 // Parse this as a typename. 642 Declarator ParamDecl(DS, Declarator::TemplateParamContext); 643 ParseDeclarator(ParamDecl); 644 if (DS.getTypeSpecType() == DeclSpec::TST_unspecified) { 645 Diag(Tok.getLocation(), diag::err_expected_template_parameter); 646 return 0; 647 } 648 649 // If there is a default value, parse it. 650 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before 651 // we introduce the template parameter into the local scope. 652 SourceLocation EqualLoc; 653 ExprResult DefaultArg; 654 if (Tok.is(tok::equal)) { 655 EqualLoc = ConsumeToken(); 656 657 // C++ [temp.param]p15: 658 // When parsing a default template-argument for a non-type 659 // template-parameter, the first non-nested > is taken as the 660 // end of the template-parameter-list rather than a greater-than 661 // operator. 662 GreaterThanIsOperatorScope G(GreaterThanIsOperator, false); 663 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated); 664 665 DefaultArg = ParseAssignmentExpression(); 666 if (DefaultArg.isInvalid()) 667 SkipUntil(tok::comma, tok::greater, StopAtSemi | StopBeforeMatch); 668 } 669 670 // Create the parameter. 671 return Actions.ActOnNonTypeTemplateParameter(getCurScope(), ParamDecl, 672 Depth, Position, EqualLoc, 673 DefaultArg.take()); 674} 675 676/// \brief Parses a '>' at the end of a template list. 677/// 678/// If this function encounters '>>', '>>>', '>=', or '>>=', it tries 679/// to determine if these tokens were supposed to be a '>' followed by 680/// '>', '>>', '>=', or '>='. It emits an appropriate diagnostic if necessary. 681/// 682/// \param RAngleLoc the location of the consumed '>'. 683/// 684/// \param ConsumeLastToken if true, the '>' is not consumed. 685/// 686/// \returns true, if current token does not start with '>', false otherwise. 687bool Parser::ParseGreaterThanInTemplateList(SourceLocation &RAngleLoc, 688 bool ConsumeLastToken) { 689 // What will be left once we've consumed the '>'. 690 tok::TokenKind RemainingToken; 691 const char *ReplacementStr = "> >"; 692 693 switch (Tok.getKind()) { 694 default: 695 Diag(Tok.getLocation(), diag::err_expected_greater); 696 return true; 697 698 case tok::greater: 699 // Determine the location of the '>' token. Only consume this token 700 // if the caller asked us to. 701 RAngleLoc = Tok.getLocation(); 702 if (ConsumeLastToken) 703 ConsumeToken(); 704 return false; 705 706 case tok::greatergreater: 707 RemainingToken = tok::greater; 708 break; 709 710 case tok::greatergreatergreater: 711 RemainingToken = tok::greatergreater; 712 break; 713 714 case tok::greaterequal: 715 RemainingToken = tok::equal; 716 ReplacementStr = "> ="; 717 break; 718 719 case tok::greatergreaterequal: 720 RemainingToken = tok::greaterequal; 721 break; 722 } 723 724 // This template-id is terminated by a token which starts with a '>'. Outside 725 // C++11, this is now error recovery, and in C++11, this is error recovery if 726 // the token isn't '>>'. 727 728 RAngleLoc = Tok.getLocation(); 729 730 // The source range of the '>>' or '>=' at the start of the token. 731 CharSourceRange ReplacementRange = 732 CharSourceRange::getCharRange(RAngleLoc, 733 Lexer::AdvanceToTokenCharacter(RAngleLoc, 2, PP.getSourceManager(), 734 getLangOpts())); 735 736 // A hint to put a space between the '>>'s. In order to make the hint as 737 // clear as possible, we include the characters either side of the space in 738 // the replacement, rather than just inserting a space at SecondCharLoc. 739 FixItHint Hint1 = FixItHint::CreateReplacement(ReplacementRange, 740 ReplacementStr); 741 742 // A hint to put another space after the token, if it would otherwise be 743 // lexed differently. 744 FixItHint Hint2; 745 Token Next = NextToken(); 746 if ((RemainingToken == tok::greater || 747 RemainingToken == tok::greatergreater) && 748 (Next.is(tok::greater) || Next.is(tok::greatergreater) || 749 Next.is(tok::greatergreatergreater) || Next.is(tok::equal) || 750 Next.is(tok::greaterequal) || Next.is(tok::greatergreaterequal) || 751 Next.is(tok::equalequal)) && 752 areTokensAdjacent(Tok, Next)) 753 Hint2 = FixItHint::CreateInsertion(Next.getLocation(), " "); 754 755 unsigned DiagId = diag::err_two_right_angle_brackets_need_space; 756 if (getLangOpts().CPlusPlus11 && Tok.is(tok::greatergreater)) 757 DiagId = diag::warn_cxx98_compat_two_right_angle_brackets; 758 else if (Tok.is(tok::greaterequal)) 759 DiagId = diag::err_right_angle_bracket_equal_needs_space; 760 Diag(Tok.getLocation(), DiagId) << Hint1 << Hint2; 761 762 // Strip the initial '>' from the token. 763 if (RemainingToken == tok::equal && Next.is(tok::equal) && 764 areTokensAdjacent(Tok, Next)) { 765 // Join two adjacent '=' tokens into one, for cases like: 766 // void (*p)() = f<int>; 767 // return f<int>==p; 768 ConsumeToken(); 769 Tok.setKind(tok::equalequal); 770 Tok.setLength(Tok.getLength() + 1); 771 } else { 772 Tok.setKind(RemainingToken); 773 Tok.setLength(Tok.getLength() - 1); 774 } 775 Tok.setLocation(Lexer::AdvanceToTokenCharacter(RAngleLoc, 1, 776 PP.getSourceManager(), 777 getLangOpts())); 778 779 if (!ConsumeLastToken) { 780 // Since we're not supposed to consume the '>' token, we need to push 781 // this token and revert the current token back to the '>'. 782 PP.EnterToken(Tok); 783 Tok.setKind(tok::greater); 784 Tok.setLength(1); 785 Tok.setLocation(RAngleLoc); 786 } 787 return false; 788} 789 790 791/// \brief Parses a template-id that after the template name has 792/// already been parsed. 793/// 794/// This routine takes care of parsing the enclosed template argument 795/// list ('<' template-parameter-list [opt] '>') and placing the 796/// results into a form that can be transferred to semantic analysis. 797/// 798/// \param Template the template declaration produced by isTemplateName 799/// 800/// \param TemplateNameLoc the source location of the template name 801/// 802/// \param SS if non-NULL, the nested-name-specifier preceding the 803/// template name. 804/// 805/// \param ConsumeLastToken if true, then we will consume the last 806/// token that forms the template-id. Otherwise, we will leave the 807/// last token in the stream (e.g., so that it can be replaced with an 808/// annotation token). 809bool 810Parser::ParseTemplateIdAfterTemplateName(TemplateTy Template, 811 SourceLocation TemplateNameLoc, 812 const CXXScopeSpec &SS, 813 bool ConsumeLastToken, 814 SourceLocation &LAngleLoc, 815 TemplateArgList &TemplateArgs, 816 SourceLocation &RAngleLoc) { 817 assert(Tok.is(tok::less) && "Must have already parsed the template-name"); 818 819 // Consume the '<'. 820 LAngleLoc = ConsumeToken(); 821 822 // Parse the optional template-argument-list. 823 bool Invalid = false; 824 { 825 GreaterThanIsOperatorScope G(GreaterThanIsOperator, false); 826 if (Tok.isNot(tok::greater) && Tok.isNot(tok::greatergreater)) 827 Invalid = ParseTemplateArgumentList(TemplateArgs); 828 829 if (Invalid) { 830 // Try to find the closing '>'. 831 if (ConsumeLastToken) 832 SkipUntil(tok::greater, StopAtSemi); 833 else 834 SkipUntil(tok::greater, StopAtSemi | StopBeforeMatch); 835 return true; 836 } 837 } 838 839 return ParseGreaterThanInTemplateList(RAngleLoc, ConsumeLastToken); 840} 841 842/// \brief Replace the tokens that form a simple-template-id with an 843/// annotation token containing the complete template-id. 844/// 845/// The first token in the stream must be the name of a template that 846/// is followed by a '<'. This routine will parse the complete 847/// simple-template-id and replace the tokens with a single annotation 848/// token with one of two different kinds: if the template-id names a 849/// type (and \p AllowTypeAnnotation is true), the annotation token is 850/// a type annotation that includes the optional nested-name-specifier 851/// (\p SS). Otherwise, the annotation token is a template-id 852/// annotation that does not include the optional 853/// nested-name-specifier. 854/// 855/// \param Template the declaration of the template named by the first 856/// token (an identifier), as returned from \c Action::isTemplateName(). 857/// 858/// \param TNK the kind of template that \p Template 859/// refers to, as returned from \c Action::isTemplateName(). 860/// 861/// \param SS if non-NULL, the nested-name-specifier that precedes 862/// this template name. 863/// 864/// \param TemplateKWLoc if valid, specifies that this template-id 865/// annotation was preceded by the 'template' keyword and gives the 866/// location of that keyword. If invalid (the default), then this 867/// template-id was not preceded by a 'template' keyword. 868/// 869/// \param AllowTypeAnnotation if true (the default), then a 870/// simple-template-id that refers to a class template, template 871/// template parameter, or other template that produces a type will be 872/// replaced with a type annotation token. Otherwise, the 873/// simple-template-id is always replaced with a template-id 874/// annotation token. 875/// 876/// If an unrecoverable parse error occurs and no annotation token can be 877/// formed, this function returns true. 878/// 879bool Parser::AnnotateTemplateIdToken(TemplateTy Template, TemplateNameKind TNK, 880 CXXScopeSpec &SS, 881 SourceLocation TemplateKWLoc, 882 UnqualifiedId &TemplateName, 883 bool AllowTypeAnnotation) { 884 assert(getLangOpts().CPlusPlus && "Can only annotate template-ids in C++"); 885 assert(Template && Tok.is(tok::less) && 886 "Parser isn't at the beginning of a template-id"); 887 888 // Consume the template-name. 889 SourceLocation TemplateNameLoc = TemplateName.getSourceRange().getBegin(); 890 891 // Parse the enclosed template argument list. 892 SourceLocation LAngleLoc, RAngleLoc; 893 TemplateArgList TemplateArgs; 894 bool Invalid = ParseTemplateIdAfterTemplateName(Template, 895 TemplateNameLoc, 896 SS, false, LAngleLoc, 897 TemplateArgs, 898 RAngleLoc); 899 900 if (Invalid) { 901 // If we failed to parse the template ID but skipped ahead to a >, we're not 902 // going to be able to form a token annotation. Eat the '>' if present. 903 if (Tok.is(tok::greater)) 904 ConsumeToken(); 905 return true; 906 } 907 908 ASTTemplateArgsPtr TemplateArgsPtr(TemplateArgs); 909 910 // Build the annotation token. 911 if (TNK == TNK_Type_template && AllowTypeAnnotation) { 912 TypeResult Type 913 = Actions.ActOnTemplateIdType(SS, TemplateKWLoc, 914 Template, TemplateNameLoc, 915 LAngleLoc, TemplateArgsPtr, RAngleLoc); 916 if (Type.isInvalid()) { 917 // If we failed to parse the template ID but skipped ahead to a >, we're not 918 // going to be able to form a token annotation. Eat the '>' if present. 919 if (Tok.is(tok::greater)) 920 ConsumeToken(); 921 return true; 922 } 923 924 Tok.setKind(tok::annot_typename); 925 setTypeAnnotation(Tok, Type.get()); 926 if (SS.isNotEmpty()) 927 Tok.setLocation(SS.getBeginLoc()); 928 else if (TemplateKWLoc.isValid()) 929 Tok.setLocation(TemplateKWLoc); 930 else 931 Tok.setLocation(TemplateNameLoc); 932 } else { 933 // Build a template-id annotation token that can be processed 934 // later. 935 Tok.setKind(tok::annot_template_id); 936 TemplateIdAnnotation *TemplateId 937 = TemplateIdAnnotation::Allocate(TemplateArgs.size(), TemplateIds); 938 TemplateId->TemplateNameLoc = TemplateNameLoc; 939 if (TemplateName.getKind() == UnqualifiedId::IK_Identifier) { 940 TemplateId->Name = TemplateName.Identifier; 941 TemplateId->Operator = OO_None; 942 } else { 943 TemplateId->Name = 0; 944 TemplateId->Operator = TemplateName.OperatorFunctionId.Operator; 945 } 946 TemplateId->SS = SS; 947 TemplateId->TemplateKWLoc = TemplateKWLoc; 948 TemplateId->Template = Template; 949 TemplateId->Kind = TNK; 950 TemplateId->LAngleLoc = LAngleLoc; 951 TemplateId->RAngleLoc = RAngleLoc; 952 ParsedTemplateArgument *Args = TemplateId->getTemplateArgs(); 953 for (unsigned Arg = 0, ArgEnd = TemplateArgs.size(); Arg != ArgEnd; ++Arg) 954 Args[Arg] = ParsedTemplateArgument(TemplateArgs[Arg]); 955 Tok.setAnnotationValue(TemplateId); 956 if (TemplateKWLoc.isValid()) 957 Tok.setLocation(TemplateKWLoc); 958 else 959 Tok.setLocation(TemplateNameLoc); 960 } 961 962 // Common fields for the annotation token 963 Tok.setAnnotationEndLoc(RAngleLoc); 964 965 // In case the tokens were cached, have Preprocessor replace them with the 966 // annotation token. 967 PP.AnnotateCachedTokens(Tok); 968 return false; 969} 970 971/// \brief Replaces a template-id annotation token with a type 972/// annotation token. 973/// 974/// If there was a failure when forming the type from the template-id, 975/// a type annotation token will still be created, but will have a 976/// NULL type pointer to signify an error. 977void Parser::AnnotateTemplateIdTokenAsType() { 978 assert(Tok.is(tok::annot_template_id) && "Requires template-id tokens"); 979 980 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok); 981 assert((TemplateId->Kind == TNK_Type_template || 982 TemplateId->Kind == TNK_Dependent_template_name) && 983 "Only works for type and dependent templates"); 984 985 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(), 986 TemplateId->NumArgs); 987 988 TypeResult Type 989 = Actions.ActOnTemplateIdType(TemplateId->SS, 990 TemplateId->TemplateKWLoc, 991 TemplateId->Template, 992 TemplateId->TemplateNameLoc, 993 TemplateId->LAngleLoc, 994 TemplateArgsPtr, 995 TemplateId->RAngleLoc); 996 // Create the new "type" annotation token. 997 Tok.setKind(tok::annot_typename); 998 setTypeAnnotation(Tok, Type.isInvalid() ? ParsedType() : Type.get()); 999 if (TemplateId->SS.isNotEmpty()) // it was a C++ qualified type name. 1000 Tok.setLocation(TemplateId->SS.getBeginLoc()); 1001 // End location stays the same 1002 1003 // Replace the template-id annotation token, and possible the scope-specifier 1004 // that precedes it, with the typename annotation token. 1005 PP.AnnotateCachedTokens(Tok); 1006} 1007 1008/// \brief Determine whether the given token can end a template argument. 1009static bool isEndOfTemplateArgument(Token Tok) { 1010 return Tok.is(tok::comma) || Tok.is(tok::greater) || 1011 Tok.is(tok::greatergreater); 1012} 1013 1014/// \brief Parse a C++ template template argument. 1015ParsedTemplateArgument Parser::ParseTemplateTemplateArgument() { 1016 if (!Tok.is(tok::identifier) && !Tok.is(tok::coloncolon) && 1017 !Tok.is(tok::annot_cxxscope)) 1018 return ParsedTemplateArgument(); 1019 1020 // C++0x [temp.arg.template]p1: 1021 // A template-argument for a template template-parameter shall be the name 1022 // of a class template or an alias template, expressed as id-expression. 1023 // 1024 // We parse an id-expression that refers to a class template or alias 1025 // template. The grammar we parse is: 1026 // 1027 // nested-name-specifier[opt] template[opt] identifier ...[opt] 1028 // 1029 // followed by a token that terminates a template argument, such as ',', 1030 // '>', or (in some cases) '>>'. 1031 CXXScopeSpec SS; // nested-name-specifier, if present 1032 ParseOptionalCXXScopeSpecifier(SS, ParsedType(), 1033 /*EnteringContext=*/false); 1034 1035 ParsedTemplateArgument Result; 1036 SourceLocation EllipsisLoc; 1037 if (SS.isSet() && Tok.is(tok::kw_template)) { 1038 // Parse the optional 'template' keyword following the 1039 // nested-name-specifier. 1040 SourceLocation TemplateKWLoc = ConsumeToken(); 1041 1042 if (Tok.is(tok::identifier)) { 1043 // We appear to have a dependent template name. 1044 UnqualifiedId Name; 1045 Name.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation()); 1046 ConsumeToken(); // the identifier 1047 1048 // Parse the ellipsis. 1049 if (Tok.is(tok::ellipsis)) 1050 EllipsisLoc = ConsumeToken(); 1051 1052 // If the next token signals the end of a template argument, 1053 // then we have a dependent template name that could be a template 1054 // template argument. 1055 TemplateTy Template; 1056 if (isEndOfTemplateArgument(Tok) && 1057 Actions.ActOnDependentTemplateName(getCurScope(), 1058 SS, TemplateKWLoc, Name, 1059 /*ObjectType=*/ ParsedType(), 1060 /*EnteringContext=*/false, 1061 Template)) 1062 Result = ParsedTemplateArgument(SS, Template, Name.StartLocation); 1063 } 1064 } else if (Tok.is(tok::identifier)) { 1065 // We may have a (non-dependent) template name. 1066 TemplateTy Template; 1067 UnqualifiedId Name; 1068 Name.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation()); 1069 ConsumeToken(); // the identifier 1070 1071 // Parse the ellipsis. 1072 if (Tok.is(tok::ellipsis)) 1073 EllipsisLoc = ConsumeToken(); 1074 1075 if (isEndOfTemplateArgument(Tok)) { 1076 bool MemberOfUnknownSpecialization; 1077 TemplateNameKind TNK = Actions.isTemplateName(getCurScope(), SS, 1078 /*hasTemplateKeyword=*/false, 1079 Name, 1080 /*ObjectType=*/ ParsedType(), 1081 /*EnteringContext=*/false, 1082 Template, 1083 MemberOfUnknownSpecialization); 1084 if (TNK == TNK_Dependent_template_name || TNK == TNK_Type_template) { 1085 // We have an id-expression that refers to a class template or 1086 // (C++0x) alias template. 1087 Result = ParsedTemplateArgument(SS, Template, Name.StartLocation); 1088 } 1089 } 1090 } 1091 1092 // If this is a pack expansion, build it as such. 1093 if (EllipsisLoc.isValid() && !Result.isInvalid()) 1094 Result = Actions.ActOnPackExpansion(Result, EllipsisLoc); 1095 1096 return Result; 1097} 1098 1099/// ParseTemplateArgument - Parse a C++ template argument (C++ [temp.names]). 1100/// 1101/// template-argument: [C++ 14.2] 1102/// constant-expression 1103/// type-id 1104/// id-expression 1105ParsedTemplateArgument Parser::ParseTemplateArgument() { 1106 // C++ [temp.arg]p2: 1107 // In a template-argument, an ambiguity between a type-id and an 1108 // expression is resolved to a type-id, regardless of the form of 1109 // the corresponding template-parameter. 1110 // 1111 // Therefore, we initially try to parse a type-id. 1112 if (isCXXTypeId(TypeIdAsTemplateArgument)) { 1113 SourceLocation Loc = Tok.getLocation(); 1114 TypeResult TypeArg = ParseTypeName(/*Range=*/0, 1115 Declarator::TemplateTypeArgContext); 1116 if (TypeArg.isInvalid()) 1117 return ParsedTemplateArgument(); 1118 1119 return ParsedTemplateArgument(ParsedTemplateArgument::Type, 1120 TypeArg.get().getAsOpaquePtr(), 1121 Loc); 1122 } 1123 1124 // Try to parse a template template argument. 1125 { 1126 TentativeParsingAction TPA(*this); 1127 1128 ParsedTemplateArgument TemplateTemplateArgument 1129 = ParseTemplateTemplateArgument(); 1130 if (!TemplateTemplateArgument.isInvalid()) { 1131 TPA.Commit(); 1132 return TemplateTemplateArgument; 1133 } 1134 1135 // Revert this tentative parse to parse a non-type template argument. 1136 TPA.Revert(); 1137 } 1138 1139 // Parse a non-type template argument. 1140 SourceLocation Loc = Tok.getLocation(); 1141 ExprResult ExprArg = ParseConstantExpression(MaybeTypeCast); 1142 if (ExprArg.isInvalid() || !ExprArg.get()) 1143 return ParsedTemplateArgument(); 1144 1145 return ParsedTemplateArgument(ParsedTemplateArgument::NonType, 1146 ExprArg.release(), Loc); 1147} 1148 1149/// \brief Determine whether the current tokens can only be parsed as a 1150/// template argument list (starting with the '<') and never as a '<' 1151/// expression. 1152bool Parser::IsTemplateArgumentList(unsigned Skip) { 1153 struct AlwaysRevertAction : TentativeParsingAction { 1154 AlwaysRevertAction(Parser &P) : TentativeParsingAction(P) { } 1155 ~AlwaysRevertAction() { Revert(); } 1156 } Tentative(*this); 1157 1158 while (Skip) { 1159 ConsumeToken(); 1160 --Skip; 1161 } 1162 1163 // '<' 1164 if (!Tok.is(tok::less)) 1165 return false; 1166 ConsumeToken(); 1167 1168 // An empty template argument list. 1169 if (Tok.is(tok::greater)) 1170 return true; 1171 1172 // See whether we have declaration specifiers, which indicate a type. 1173 while (isCXXDeclarationSpecifier() == TPResult::True()) 1174 ConsumeToken(); 1175 1176 // If we have a '>' or a ',' then this is a template argument list. 1177 return Tok.is(tok::greater) || Tok.is(tok::comma); 1178} 1179 1180/// ParseTemplateArgumentList - Parse a C++ template-argument-list 1181/// (C++ [temp.names]). Returns true if there was an error. 1182/// 1183/// template-argument-list: [C++ 14.2] 1184/// template-argument 1185/// template-argument-list ',' template-argument 1186bool 1187Parser::ParseTemplateArgumentList(TemplateArgList &TemplateArgs) { 1188 // Template argument lists are constant-evaluation contexts. 1189 EnterExpressionEvaluationContext EvalContext(Actions,Sema::ConstantEvaluated); 1190 1191 while (true) { 1192 ParsedTemplateArgument Arg = ParseTemplateArgument(); 1193 if (Tok.is(tok::ellipsis)) { 1194 SourceLocation EllipsisLoc = ConsumeToken(); 1195 Arg = Actions.ActOnPackExpansion(Arg, EllipsisLoc); 1196 } 1197 1198 if (Arg.isInvalid()) { 1199 SkipUntil(tok::comma, tok::greater, StopAtSemi | StopBeforeMatch); 1200 return true; 1201 } 1202 1203 // Save this template argument. 1204 TemplateArgs.push_back(Arg); 1205 1206 // If the next token is a comma, consume it and keep reading 1207 // arguments. 1208 if (Tok.isNot(tok::comma)) break; 1209 1210 // Consume the comma. 1211 ConsumeToken(); 1212 } 1213 1214 return false; 1215} 1216 1217/// \brief Parse a C++ explicit template instantiation 1218/// (C++ [temp.explicit]). 1219/// 1220/// explicit-instantiation: 1221/// 'extern' [opt] 'template' declaration 1222/// 1223/// Note that the 'extern' is a GNU extension and C++11 feature. 1224Decl *Parser::ParseExplicitInstantiation(unsigned Context, 1225 SourceLocation ExternLoc, 1226 SourceLocation TemplateLoc, 1227 SourceLocation &DeclEnd, 1228 AccessSpecifier AS) { 1229 // This isn't really required here. 1230 ParsingDeclRAIIObject 1231 ParsingTemplateParams(*this, ParsingDeclRAIIObject::NoParent); 1232 1233 return ParseSingleDeclarationAfterTemplate(Context, 1234 ParsedTemplateInfo(ExternLoc, 1235 TemplateLoc), 1236 ParsingTemplateParams, 1237 DeclEnd, AS); 1238} 1239 1240SourceRange Parser::ParsedTemplateInfo::getSourceRange() const { 1241 if (TemplateParams) 1242 return getTemplateParamsRange(TemplateParams->data(), 1243 TemplateParams->size()); 1244 1245 SourceRange R(TemplateLoc); 1246 if (ExternLoc.isValid()) 1247 R.setBegin(ExternLoc); 1248 return R; 1249} 1250 1251void Parser::LateTemplateParserCallback(void *P, LateParsedTemplate &LPT) { 1252 ((Parser *)P)->ParseLateTemplatedFuncDef(LPT); 1253} 1254 1255/// \brief Late parse a C++ function template in Microsoft mode. 1256void Parser::ParseLateTemplatedFuncDef(LateParsedTemplate &LPT) { 1257 if (!LPT.D) 1258 return; 1259 1260 // Get the FunctionDecl. 1261 FunctionTemplateDecl *FunTmplD = dyn_cast<FunctionTemplateDecl>(LPT.D); 1262 FunctionDecl *FunD = 1263 FunTmplD ? FunTmplD->getTemplatedDecl() : cast<FunctionDecl>(LPT.D); 1264 // Track template parameter depth. 1265 TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth); 1266 1267 // To restore the context after late parsing. 1268 Sema::ContextRAII GlobalSavedContext(Actions, Actions.CurContext); 1269 1270 SmallVector<ParseScope*, 4> TemplateParamScopeStack; 1271 1272 // Get the list of DeclContexts to reenter. 1273 SmallVector<DeclContext*, 4> DeclContextsToReenter; 1274 DeclContext *DD = FunD->getLexicalParent(); 1275 while (DD && !DD->isTranslationUnit()) { 1276 DeclContextsToReenter.push_back(DD); 1277 DD = DD->getLexicalParent(); 1278 } 1279 1280 // Reenter template scopes from outermost to innermost. 1281 SmallVectorImpl<DeclContext *>::reverse_iterator II = 1282 DeclContextsToReenter.rbegin(); 1283 for (; II != DeclContextsToReenter.rend(); ++II) { 1284 if (ClassTemplatePartialSpecializationDecl *MD = 1285 dyn_cast_or_null<ClassTemplatePartialSpecializationDecl>(*II)) { 1286 TemplateParamScopeStack.push_back( 1287 new ParseScope(this, Scope::TemplateParamScope)); 1288 Actions.ActOnReenterTemplateScope(getCurScope(), MD); 1289 ++CurTemplateDepthTracker; 1290 } else if (CXXRecordDecl *MD = dyn_cast_or_null<CXXRecordDecl>(*II)) { 1291 bool IsClassTemplate = MD->getDescribedClassTemplate() != 0; 1292 TemplateParamScopeStack.push_back( 1293 new ParseScope(this, Scope::TemplateParamScope, 1294 /*ManageScope*/IsClassTemplate)); 1295 Actions.ActOnReenterTemplateScope(getCurScope(), 1296 MD->getDescribedClassTemplate()); 1297 if (IsClassTemplate) 1298 ++CurTemplateDepthTracker; 1299 } 1300 TemplateParamScopeStack.push_back(new ParseScope(this, Scope::DeclScope)); 1301 Actions.PushDeclContext(Actions.getCurScope(), *II); 1302 } 1303 TemplateParamScopeStack.push_back( 1304 new ParseScope(this, Scope::TemplateParamScope)); 1305 1306 DeclaratorDecl *Declarator = dyn_cast<DeclaratorDecl>(FunD); 1307 if (Declarator && Declarator->getNumTemplateParameterLists() != 0) { 1308 Actions.ActOnReenterDeclaratorTemplateScope(getCurScope(), Declarator); 1309 ++CurTemplateDepthTracker; 1310 } 1311 Actions.ActOnReenterTemplateScope(getCurScope(), LPT.D); 1312 ++CurTemplateDepthTracker; 1313 1314 assert(!LPT.Toks.empty() && "Empty body!"); 1315 1316 // Append the current token at the end of the new token stream so that it 1317 // doesn't get lost. 1318 LPT.Toks.push_back(Tok); 1319 PP.EnterTokenStream(LPT.Toks.data(), LPT.Toks.size(), true, false); 1320 1321 // Consume the previously pushed token. 1322 ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true); 1323 assert((Tok.is(tok::l_brace) || Tok.is(tok::colon) || Tok.is(tok::kw_try)) 1324 && "Inline method not starting with '{', ':' or 'try'"); 1325 1326 // Parse the method body. Function body parsing code is similar enough 1327 // to be re-used for method bodies as well. 1328 ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope); 1329 1330 // Recreate the containing function DeclContext. 1331 Sema::ContextRAII FunctionSavedContext(Actions, Actions.getContainingDC(FunD)); 1332 1333 Actions.ActOnStartOfFunctionDef(getCurScope(), FunD); 1334 1335 if (Tok.is(tok::kw_try)) { 1336 ParseFunctionTryBlock(LPT.D, FnScope); 1337 } else { 1338 if (Tok.is(tok::colon)) 1339 ParseConstructorInitializer(LPT.D); 1340 else 1341 Actions.ActOnDefaultCtorInitializers(LPT.D); 1342 1343 if (Tok.is(tok::l_brace)) { 1344 assert((!FunTmplD || FunTmplD->getTemplateParameters()->getDepth() < 1345 TemplateParameterDepth) && 1346 "TemplateParameterDepth should be greater than the depth of " 1347 "current template being instantiated!"); 1348 ParseFunctionStatementBody(LPT.D, FnScope); 1349 Actions.UnmarkAsLateParsedTemplate(FunD); 1350 } else 1351 Actions.ActOnFinishFunctionBody(LPT.D, 0); 1352 } 1353 1354 // Exit scopes. 1355 FnScope.Exit(); 1356 SmallVectorImpl<ParseScope *>::reverse_iterator I = 1357 TemplateParamScopeStack.rbegin(); 1358 for (; I != TemplateParamScopeStack.rend(); ++I) 1359 delete *I; 1360} 1361 1362/// \brief Lex a delayed template function for late parsing. 1363void Parser::LexTemplateFunctionForLateParsing(CachedTokens &Toks) { 1364 tok::TokenKind kind = Tok.getKind(); 1365 if (!ConsumeAndStoreFunctionPrologue(Toks)) { 1366 // Consume everything up to (and including) the matching right brace. 1367 ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false); 1368 } 1369 1370 // If we're in a function-try-block, we need to store all the catch blocks. 1371 if (kind == tok::kw_try) { 1372 while (Tok.is(tok::kw_catch)) { 1373 ConsumeAndStoreUntil(tok::l_brace, Toks, /*StopAtSemi=*/false); 1374 ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false); 1375 } 1376 } 1377} 1378