SemaTemplate.cpp revision 92ae2b40f721121f8944a1bb3c69b23d96bcff31
1//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/ 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// This file implements semantic analysis for C++ templates. 10//===----------------------------------------------------------------------===/ 11 12#include "clang/Sema/SemaInternal.h" 13#include "clang/Sema/Lookup.h" 14#include "clang/Sema/Scope.h" 15#include "clang/Sema/Template.h" 16#include "clang/Sema/TemplateDeduction.h" 17#include "TreeTransform.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/Expr.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/AST/DeclFriend.h" 22#include "clang/AST/DeclTemplate.h" 23#include "clang/Sema/DeclSpec.h" 24#include "clang/Sema/ParsedTemplate.h" 25#include "clang/Basic/LangOptions.h" 26#include "clang/Basic/PartialDiagnostic.h" 27#include "llvm/ADT/StringExtras.h" 28using namespace clang; 29using namespace sema; 30 31/// \brief Determine whether the declaration found is acceptable as the name 32/// of a template and, if so, return that template declaration. Otherwise, 33/// returns NULL. 34static NamedDecl *isAcceptableTemplateName(ASTContext &Context, 35 NamedDecl *Orig) { 36 NamedDecl *D = Orig->getUnderlyingDecl(); 37 38 if (isa<TemplateDecl>(D)) 39 return Orig; 40 41 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) { 42 // C++ [temp.local]p1: 43 // Like normal (non-template) classes, class templates have an 44 // injected-class-name (Clause 9). The injected-class-name 45 // can be used with or without a template-argument-list. When 46 // it is used without a template-argument-list, it is 47 // equivalent to the injected-class-name followed by the 48 // template-parameters of the class template enclosed in 49 // <>. When it is used with a template-argument-list, it 50 // refers to the specified class template specialization, 51 // which could be the current specialization or another 52 // specialization. 53 if (Record->isInjectedClassName()) { 54 Record = cast<CXXRecordDecl>(Record->getDeclContext()); 55 if (Record->getDescribedClassTemplate()) 56 return Record->getDescribedClassTemplate(); 57 58 if (ClassTemplateSpecializationDecl *Spec 59 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) 60 return Spec->getSpecializedTemplate(); 61 } 62 63 return 0; 64 } 65 66 return 0; 67} 68 69static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) { 70 // The set of class templates we've already seen. 71 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates; 72 LookupResult::Filter filter = R.makeFilter(); 73 while (filter.hasNext()) { 74 NamedDecl *Orig = filter.next(); 75 NamedDecl *Repl = isAcceptableTemplateName(C, Orig); 76 if (!Repl) 77 filter.erase(); 78 else if (Repl != Orig) { 79 80 // C++ [temp.local]p3: 81 // A lookup that finds an injected-class-name (10.2) can result in an 82 // ambiguity in certain cases (for example, if it is found in more than 83 // one base class). If all of the injected-class-names that are found 84 // refer to specializations of the same class template, and if the name 85 // is followed by a template-argument-list, the reference refers to the 86 // class template itself and not a specialization thereof, and is not 87 // ambiguous. 88 // 89 // FIXME: Will we eventually have to do the same for alias templates? 90 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl)) 91 if (!ClassTemplates.insert(ClassTmpl)) { 92 filter.erase(); 93 continue; 94 } 95 96 // FIXME: we promote access to public here as a workaround to 97 // the fact that LookupResult doesn't let us remember that we 98 // found this template through a particular injected class name, 99 // which means we end up doing nasty things to the invariants. 100 // Pretending that access is public is *much* safer. 101 filter.replace(Repl, AS_public); 102 } 103 } 104 filter.done(); 105} 106 107TemplateNameKind Sema::isTemplateName(Scope *S, 108 CXXScopeSpec &SS, 109 bool hasTemplateKeyword, 110 UnqualifiedId &Name, 111 ParsedType ObjectTypePtr, 112 bool EnteringContext, 113 TemplateTy &TemplateResult, 114 bool &MemberOfUnknownSpecialization) { 115 assert(getLangOptions().CPlusPlus && "No template names in C!"); 116 117 DeclarationName TName; 118 MemberOfUnknownSpecialization = false; 119 120 switch (Name.getKind()) { 121 case UnqualifiedId::IK_Identifier: 122 TName = DeclarationName(Name.Identifier); 123 break; 124 125 case UnqualifiedId::IK_OperatorFunctionId: 126 TName = Context.DeclarationNames.getCXXOperatorName( 127 Name.OperatorFunctionId.Operator); 128 break; 129 130 case UnqualifiedId::IK_LiteralOperatorId: 131 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier); 132 break; 133 134 default: 135 return TNK_Non_template; 136 } 137 138 QualType ObjectType = ObjectTypePtr.get(); 139 140 LookupResult R(*this, TName, Name.getSourceRange().getBegin(), 141 LookupOrdinaryName); 142 LookupTemplateName(R, S, SS, ObjectType, EnteringContext, 143 MemberOfUnknownSpecialization); 144 if (R.empty()) return TNK_Non_template; 145 if (R.isAmbiguous()) { 146 // Suppress diagnostics; we'll redo this lookup later. 147 R.suppressDiagnostics(); 148 149 // FIXME: we might have ambiguous templates, in which case we 150 // should at least parse them properly! 151 return TNK_Non_template; 152 } 153 154 TemplateName Template; 155 TemplateNameKind TemplateKind; 156 157 unsigned ResultCount = R.end() - R.begin(); 158 if (ResultCount > 1) { 159 // We assume that we'll preserve the qualifier from a function 160 // template name in other ways. 161 Template = Context.getOverloadedTemplateName(R.begin(), R.end()); 162 TemplateKind = TNK_Function_template; 163 164 // We'll do this lookup again later. 165 R.suppressDiagnostics(); 166 } else { 167 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl()); 168 169 if (SS.isSet() && !SS.isInvalid()) { 170 NestedNameSpecifier *Qualifier 171 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 172 Template = Context.getQualifiedTemplateName(Qualifier, 173 hasTemplateKeyword, TD); 174 } else { 175 Template = TemplateName(TD); 176 } 177 178 if (isa<FunctionTemplateDecl>(TD)) { 179 TemplateKind = TNK_Function_template; 180 181 // We'll do this lookup again later. 182 R.suppressDiagnostics(); 183 } else { 184 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD)); 185 TemplateKind = TNK_Type_template; 186 } 187 } 188 189 TemplateResult = TemplateTy::make(Template); 190 return TemplateKind; 191} 192 193bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II, 194 SourceLocation IILoc, 195 Scope *S, 196 const CXXScopeSpec *SS, 197 TemplateTy &SuggestedTemplate, 198 TemplateNameKind &SuggestedKind) { 199 // We can't recover unless there's a dependent scope specifier preceding the 200 // template name. 201 // FIXME: Typo correction? 202 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) || 203 computeDeclContext(*SS)) 204 return false; 205 206 // The code is missing a 'template' keyword prior to the dependent template 207 // name. 208 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep(); 209 Diag(IILoc, diag::err_template_kw_missing) 210 << Qualifier << II.getName() 211 << FixItHint::CreateInsertion(IILoc, "template "); 212 SuggestedTemplate 213 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II)); 214 SuggestedKind = TNK_Dependent_template_name; 215 return true; 216} 217 218void Sema::LookupTemplateName(LookupResult &Found, 219 Scope *S, CXXScopeSpec &SS, 220 QualType ObjectType, 221 bool EnteringContext, 222 bool &MemberOfUnknownSpecialization) { 223 // Determine where to perform name lookup 224 MemberOfUnknownSpecialization = false; 225 DeclContext *LookupCtx = 0; 226 bool isDependent = false; 227 if (!ObjectType.isNull()) { 228 // This nested-name-specifier occurs in a member access expression, e.g., 229 // x->B::f, and we are looking into the type of the object. 230 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 231 LookupCtx = computeDeclContext(ObjectType); 232 isDependent = ObjectType->isDependentType(); 233 assert((isDependent || !ObjectType->isIncompleteType()) && 234 "Caller should have completed object type"); 235 } else if (SS.isSet()) { 236 // This nested-name-specifier occurs after another nested-name-specifier, 237 // so long into the context associated with the prior nested-name-specifier. 238 LookupCtx = computeDeclContext(SS, EnteringContext); 239 isDependent = isDependentScopeSpecifier(SS); 240 241 // The declaration context must be complete. 242 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx)) 243 return; 244 } 245 246 bool ObjectTypeSearchedInScope = false; 247 if (LookupCtx) { 248 // Perform "qualified" name lookup into the declaration context we 249 // computed, which is either the type of the base of a member access 250 // expression or the declaration context associated with a prior 251 // nested-name-specifier. 252 LookupQualifiedName(Found, LookupCtx); 253 254 if (!ObjectType.isNull() && Found.empty()) { 255 // C++ [basic.lookup.classref]p1: 256 // In a class member access expression (5.2.5), if the . or -> token is 257 // immediately followed by an identifier followed by a <, the 258 // identifier must be looked up to determine whether the < is the 259 // beginning of a template argument list (14.2) or a less-than operator. 260 // The identifier is first looked up in the class of the object 261 // expression. If the identifier is not found, it is then looked up in 262 // the context of the entire postfix-expression and shall name a class 263 // or function template. 264 if (S) LookupName(Found, S); 265 ObjectTypeSearchedInScope = true; 266 } 267 } else if (isDependent && (!S || ObjectType.isNull())) { 268 // We cannot look into a dependent object type or nested nme 269 // specifier. 270 MemberOfUnknownSpecialization = true; 271 return; 272 } else { 273 // Perform unqualified name lookup in the current scope. 274 LookupName(Found, S); 275 } 276 277 if (Found.empty() && !isDependent) { 278 // If we did not find any names, attempt to correct any typos. 279 DeclarationName Name = Found.getLookupName(); 280 if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx, 281 false, CTC_CXXCasts)) { 282 FilterAcceptableTemplateNames(Context, Found); 283 if (!Found.empty()) { 284 if (LookupCtx) 285 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest) 286 << Name << LookupCtx << Found.getLookupName() << SS.getRange() 287 << FixItHint::CreateReplacement(Found.getNameLoc(), 288 Found.getLookupName().getAsString()); 289 else 290 Diag(Found.getNameLoc(), diag::err_no_template_suggest) 291 << Name << Found.getLookupName() 292 << FixItHint::CreateReplacement(Found.getNameLoc(), 293 Found.getLookupName().getAsString()); 294 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>()) 295 Diag(Template->getLocation(), diag::note_previous_decl) 296 << Template->getDeclName(); 297 } 298 } else { 299 Found.clear(); 300 Found.setLookupName(Name); 301 } 302 } 303 304 FilterAcceptableTemplateNames(Context, Found); 305 if (Found.empty()) { 306 if (isDependent) 307 MemberOfUnknownSpecialization = true; 308 return; 309 } 310 311 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) { 312 // C++ [basic.lookup.classref]p1: 313 // [...] If the lookup in the class of the object expression finds a 314 // template, the name is also looked up in the context of the entire 315 // postfix-expression and [...] 316 // 317 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(), 318 LookupOrdinaryName); 319 LookupName(FoundOuter, S); 320 FilterAcceptableTemplateNames(Context, FoundOuter); 321 322 if (FoundOuter.empty()) { 323 // - if the name is not found, the name found in the class of the 324 // object expression is used, otherwise 325 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) { 326 // - if the name is found in the context of the entire 327 // postfix-expression and does not name a class template, the name 328 // found in the class of the object expression is used, otherwise 329 } else if (!Found.isSuppressingDiagnostics()) { 330 // - if the name found is a class template, it must refer to the same 331 // entity as the one found in the class of the object expression, 332 // otherwise the program is ill-formed. 333 if (!Found.isSingleResult() || 334 Found.getFoundDecl()->getCanonicalDecl() 335 != FoundOuter.getFoundDecl()->getCanonicalDecl()) { 336 Diag(Found.getNameLoc(), 337 diag::ext_nested_name_member_ref_lookup_ambiguous) 338 << Found.getLookupName() 339 << ObjectType; 340 Diag(Found.getRepresentativeDecl()->getLocation(), 341 diag::note_ambig_member_ref_object_type) 342 << ObjectType; 343 Diag(FoundOuter.getFoundDecl()->getLocation(), 344 diag::note_ambig_member_ref_scope); 345 346 // Recover by taking the template that we found in the object 347 // expression's type. 348 } 349 } 350 } 351} 352 353/// ActOnDependentIdExpression - Handle a dependent id-expression that 354/// was just parsed. This is only possible with an explicit scope 355/// specifier naming a dependent type. 356ExprResult 357Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS, 358 const DeclarationNameInfo &NameInfo, 359 bool isAddressOfOperand, 360 const TemplateArgumentListInfo *TemplateArgs) { 361 NestedNameSpecifier *Qualifier 362 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 363 364 DeclContext *DC = getFunctionLevelDeclContext(); 365 366 if (!isAddressOfOperand && 367 isa<CXXMethodDecl>(DC) && 368 cast<CXXMethodDecl>(DC)->isInstance()) { 369 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); 370 371 // Since the 'this' expression is synthesized, we don't need to 372 // perform the double-lookup check. 373 NamedDecl *FirstQualifierInScope = 0; 374 375 return Owned(CXXDependentScopeMemberExpr::Create(Context, 376 /*This*/ 0, ThisType, 377 /*IsArrow*/ true, 378 /*Op*/ SourceLocation(), 379 Qualifier, SS.getRange(), 380 FirstQualifierInScope, 381 NameInfo, 382 TemplateArgs)); 383 } 384 385 return BuildDependentDeclRefExpr(SS, NameInfo, TemplateArgs); 386} 387 388ExprResult 389Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS, 390 const DeclarationNameInfo &NameInfo, 391 const TemplateArgumentListInfo *TemplateArgs) { 392 return Owned(DependentScopeDeclRefExpr::Create(Context, 393 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 394 SS.getRange(), 395 NameInfo, 396 TemplateArgs)); 397} 398 399/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining 400/// that the template parameter 'PrevDecl' is being shadowed by a new 401/// declaration at location Loc. Returns true to indicate that this is 402/// an error, and false otherwise. 403bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { 404 assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); 405 406 // Microsoft Visual C++ permits template parameters to be shadowed. 407 if (getLangOptions().Microsoft) 408 return false; 409 410 // C++ [temp.local]p4: 411 // A template-parameter shall not be redeclared within its 412 // scope (including nested scopes). 413 Diag(Loc, diag::err_template_param_shadow) 414 << cast<NamedDecl>(PrevDecl)->getDeclName(); 415 Diag(PrevDecl->getLocation(), diag::note_template_param_here); 416 return true; 417} 418 419/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset 420/// the parameter D to reference the templated declaration and return a pointer 421/// to the template declaration. Otherwise, do nothing to D and return null. 422TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) { 423 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) { 424 D = Temp->getTemplatedDecl(); 425 return Temp; 426 } 427 return 0; 428} 429 430static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, 431 const ParsedTemplateArgument &Arg) { 432 433 switch (Arg.getKind()) { 434 case ParsedTemplateArgument::Type: { 435 TypeSourceInfo *DI; 436 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); 437 if (!DI) 438 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation()); 439 return TemplateArgumentLoc(TemplateArgument(T), DI); 440 } 441 442 case ParsedTemplateArgument::NonType: { 443 Expr *E = static_cast<Expr *>(Arg.getAsExpr()); 444 return TemplateArgumentLoc(TemplateArgument(E), E); 445 } 446 447 case ParsedTemplateArgument::Template: { 448 TemplateName Template = Arg.getAsTemplate().get(); 449 return TemplateArgumentLoc(TemplateArgument(Template), 450 Arg.getScopeSpec().getRange(), 451 Arg.getLocation()); 452 } 453 } 454 455 llvm_unreachable("Unhandled parsed template argument"); 456 return TemplateArgumentLoc(); 457} 458 459/// \brief Translates template arguments as provided by the parser 460/// into template arguments used by semantic analysis. 461void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn, 462 TemplateArgumentListInfo &TemplateArgs) { 463 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) 464 TemplateArgs.addArgument(translateTemplateArgument(*this, 465 TemplateArgsIn[I])); 466} 467 468/// ActOnTypeParameter - Called when a C++ template type parameter 469/// (e.g., "typename T") has been parsed. Typename specifies whether 470/// the keyword "typename" was used to declare the type parameter 471/// (otherwise, "class" was used), and KeyLoc is the location of the 472/// "class" or "typename" keyword. ParamName is the name of the 473/// parameter (NULL indicates an unnamed template parameter) and 474/// ParamName is the location of the parameter name (if any). 475/// If the type parameter has a default argument, it will be added 476/// later via ActOnTypeParameterDefault. 477Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, 478 SourceLocation EllipsisLoc, 479 SourceLocation KeyLoc, 480 IdentifierInfo *ParamName, 481 SourceLocation ParamNameLoc, 482 unsigned Depth, unsigned Position, 483 SourceLocation EqualLoc, 484 ParsedType DefaultArg) { 485 assert(S->isTemplateParamScope() && 486 "Template type parameter not in template parameter scope!"); 487 bool Invalid = false; 488 489 if (ParamName) { 490 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc, 491 LookupOrdinaryName, 492 ForRedeclaration); 493 if (PrevDecl && PrevDecl->isTemplateParameter()) 494 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc, 495 PrevDecl); 496 } 497 498 SourceLocation Loc = ParamNameLoc; 499 if (!ParamName) 500 Loc = KeyLoc; 501 502 TemplateTypeParmDecl *Param 503 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(), 504 Loc, Depth, Position, ParamName, Typename, 505 Ellipsis); 506 if (Invalid) 507 Param->setInvalidDecl(); 508 509 if (ParamName) { 510 // Add the template parameter into the current scope. 511 S->AddDecl(Param); 512 IdResolver.AddDecl(Param); 513 } 514 515 // Handle the default argument, if provided. 516 if (DefaultArg) { 517 TypeSourceInfo *DefaultTInfo; 518 GetTypeFromParser(DefaultArg, &DefaultTInfo); 519 520 assert(DefaultTInfo && "expected source information for type"); 521 522 // C++0x [temp.param]p9: 523 // A default template-argument may be specified for any kind of 524 // template-parameter that is not a template parameter pack. 525 if (Ellipsis) { 526 Diag(EqualLoc, diag::err_template_param_pack_default_arg); 527 return Param; 528 } 529 530 // Check the template argument itself. 531 if (CheckTemplateArgument(Param, DefaultTInfo)) { 532 Param->setInvalidDecl(); 533 return Param; 534 } 535 536 Param->setDefaultArgument(DefaultTInfo, false); 537 } 538 539 return Param; 540} 541 542/// \brief Check that the type of a non-type template parameter is 543/// well-formed. 544/// 545/// \returns the (possibly-promoted) parameter type if valid; 546/// otherwise, produces a diagnostic and returns a NULL type. 547QualType 548Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { 549 // We don't allow variably-modified types as the type of non-type template 550 // parameters. 551 if (T->isVariablyModifiedType()) { 552 Diag(Loc, diag::err_variably_modified_nontype_template_param) 553 << T; 554 return QualType(); 555 } 556 557 // C++ [temp.param]p4: 558 // 559 // A non-type template-parameter shall have one of the following 560 // (optionally cv-qualified) types: 561 // 562 // -- integral or enumeration type, 563 if (T->isIntegralOrEnumerationType() || 564 // -- pointer to object or pointer to function, 565 T->isPointerType() || 566 // -- reference to object or reference to function, 567 T->isReferenceType() || 568 // -- pointer to member. 569 T->isMemberPointerType() || 570 // If T is a dependent type, we can't do the check now, so we 571 // assume that it is well-formed. 572 T->isDependentType()) 573 return T; 574 // C++ [temp.param]p8: 575 // 576 // A non-type template-parameter of type "array of T" or 577 // "function returning T" is adjusted to be of type "pointer to 578 // T" or "pointer to function returning T", respectively. 579 else if (T->isArrayType()) 580 // FIXME: Keep the type prior to promotion? 581 return Context.getArrayDecayedType(T); 582 else if (T->isFunctionType()) 583 // FIXME: Keep the type prior to promotion? 584 return Context.getPointerType(T); 585 586 Diag(Loc, diag::err_template_nontype_parm_bad_type) 587 << T; 588 589 return QualType(); 590} 591 592Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, 593 unsigned Depth, 594 unsigned Position, 595 SourceLocation EqualLoc, 596 Expr *Default) { 597 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 598 QualType T = TInfo->getType(); 599 600 assert(S->isTemplateParamScope() && 601 "Non-type template parameter not in template parameter scope!"); 602 bool Invalid = false; 603 604 IdentifierInfo *ParamName = D.getIdentifier(); 605 if (ParamName) { 606 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(), 607 LookupOrdinaryName, 608 ForRedeclaration); 609 if (PrevDecl && PrevDecl->isTemplateParameter()) 610 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 611 PrevDecl); 612 } 613 614 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); 615 if (T.isNull()) { 616 T = Context.IntTy; // Recover with an 'int' type. 617 Invalid = true; 618 } 619 620 NonTypeTemplateParmDecl *Param 621 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 622 D.getIdentifierLoc(), 623 Depth, Position, ParamName, T, TInfo); 624 if (Invalid) 625 Param->setInvalidDecl(); 626 627 if (D.getIdentifier()) { 628 // Add the template parameter into the current scope. 629 S->AddDecl(Param); 630 IdResolver.AddDecl(Param); 631 } 632 633 // Check the well-formedness of the default template argument, if provided. 634 if (Default) { 635 TemplateArgument Converted; 636 if (CheckTemplateArgument(Param, Param->getType(), Default, Converted)) { 637 Param->setInvalidDecl(); 638 return Param; 639 } 640 641 Param->setDefaultArgument(Default, false); 642 } 643 644 return Param; 645} 646 647/// ActOnTemplateTemplateParameter - Called when a C++ template template 648/// parameter (e.g. T in template <template <typename> class T> class array) 649/// has been parsed. S is the current scope. 650Decl *Sema::ActOnTemplateTemplateParameter(Scope* S, 651 SourceLocation TmpLoc, 652 TemplateParamsTy *Params, 653 IdentifierInfo *Name, 654 SourceLocation NameLoc, 655 unsigned Depth, 656 unsigned Position, 657 SourceLocation EqualLoc, 658 const ParsedTemplateArgument &Default) { 659 assert(S->isTemplateParamScope() && 660 "Template template parameter not in template parameter scope!"); 661 662 // Construct the parameter object. 663 TemplateTemplateParmDecl *Param = 664 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 665 TmpLoc, Depth, Position, Name, 666 (TemplateParameterList*)Params); 667 668 // If the template template parameter has a name, then link the identifier 669 // into the scope and lookup mechanisms. 670 if (Name) { 671 S->AddDecl(Param); 672 IdResolver.AddDecl(Param); 673 } 674 675 if (!Default.isInvalid()) { 676 // Check only that we have a template template argument. We don't want to 677 // try to check well-formedness now, because our template template parameter 678 // might have dependent types in its template parameters, which we wouldn't 679 // be able to match now. 680 // 681 // If none of the template template parameter's template arguments mention 682 // other template parameters, we could actually perform more checking here. 683 // However, it isn't worth doing. 684 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); 685 if (DefaultArg.getArgument().getAsTemplate().isNull()) { 686 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) 687 << DefaultArg.getSourceRange(); 688 return Param; 689 } 690 691 Param->setDefaultArgument(DefaultArg, false); 692 } 693 694 return Param; 695} 696 697/// ActOnTemplateParameterList - Builds a TemplateParameterList that 698/// contains the template parameters in Params/NumParams. 699Sema::TemplateParamsTy * 700Sema::ActOnTemplateParameterList(unsigned Depth, 701 SourceLocation ExportLoc, 702 SourceLocation TemplateLoc, 703 SourceLocation LAngleLoc, 704 Decl **Params, unsigned NumParams, 705 SourceLocation RAngleLoc) { 706 if (ExportLoc.isValid()) 707 Diag(ExportLoc, diag::warn_template_export_unsupported); 708 709 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, 710 (NamedDecl**)Params, NumParams, 711 RAngleLoc); 712} 713 714static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) { 715 if (SS.isSet()) 716 T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 717 SS.getRange()); 718} 719 720DeclResult 721Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, 722 SourceLocation KWLoc, CXXScopeSpec &SS, 723 IdentifierInfo *Name, SourceLocation NameLoc, 724 AttributeList *Attr, 725 TemplateParameterList *TemplateParams, 726 AccessSpecifier AS) { 727 assert(TemplateParams && TemplateParams->size() > 0 && 728 "No template parameters"); 729 assert(TUK != TUK_Reference && "Can only declare or define class templates"); 730 bool Invalid = false; 731 732 // Check that we can declare a template here. 733 if (CheckTemplateDeclScope(S, TemplateParams)) 734 return true; 735 736 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 737 assert(Kind != TTK_Enum && "can't build template of enumerated type"); 738 739 // There is no such thing as an unnamed class template. 740 if (!Name) { 741 Diag(KWLoc, diag::err_template_unnamed_class); 742 return true; 743 } 744 745 // Find any previous declaration with this name. 746 DeclContext *SemanticContext; 747 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, 748 ForRedeclaration); 749 if (SS.isNotEmpty() && !SS.isInvalid()) { 750 SemanticContext = computeDeclContext(SS, true); 751 if (!SemanticContext) { 752 // FIXME: Produce a reasonable diagnostic here 753 return true; 754 } 755 756 if (RequireCompleteDeclContext(SS, SemanticContext)) 757 return true; 758 759 LookupQualifiedName(Previous, SemanticContext); 760 } else { 761 SemanticContext = CurContext; 762 LookupName(Previous, S); 763 } 764 765 if (Previous.isAmbiguous()) 766 return true; 767 768 NamedDecl *PrevDecl = 0; 769 if (Previous.begin() != Previous.end()) 770 PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 771 772 // If there is a previous declaration with the same name, check 773 // whether this is a valid redeclaration. 774 ClassTemplateDecl *PrevClassTemplate 775 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); 776 777 // We may have found the injected-class-name of a class template, 778 // class template partial specialization, or class template specialization. 779 // In these cases, grab the template that is being defined or specialized. 780 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && 781 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { 782 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); 783 PrevClassTemplate 784 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); 785 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { 786 PrevClassTemplate 787 = cast<ClassTemplateSpecializationDecl>(PrevDecl) 788 ->getSpecializedTemplate(); 789 } 790 } 791 792 if (TUK == TUK_Friend) { 793 // C++ [namespace.memdef]p3: 794 // [...] When looking for a prior declaration of a class or a function 795 // declared as a friend, and when the name of the friend class or 796 // function is neither a qualified name nor a template-id, scopes outside 797 // the innermost enclosing namespace scope are not considered. 798 if (!SS.isSet()) { 799 DeclContext *OutermostContext = CurContext; 800 while (!OutermostContext->isFileContext()) 801 OutermostContext = OutermostContext->getLookupParent(); 802 803 if (PrevDecl && 804 (OutermostContext->Equals(PrevDecl->getDeclContext()) || 805 OutermostContext->Encloses(PrevDecl->getDeclContext()))) { 806 SemanticContext = PrevDecl->getDeclContext(); 807 } else { 808 // Declarations in outer scopes don't matter. However, the outermost 809 // context we computed is the semantic context for our new 810 // declaration. 811 PrevDecl = PrevClassTemplate = 0; 812 SemanticContext = OutermostContext; 813 } 814 } 815 816 if (CurContext->isDependentContext()) { 817 // If this is a dependent context, we don't want to link the friend 818 // class template to the template in scope, because that would perform 819 // checking of the template parameter lists that can't be performed 820 // until the outer context is instantiated. 821 PrevDecl = PrevClassTemplate = 0; 822 } 823 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) 824 PrevDecl = PrevClassTemplate = 0; 825 826 if (PrevClassTemplate) { 827 // Ensure that the template parameter lists are compatible. 828 if (!TemplateParameterListsAreEqual(TemplateParams, 829 PrevClassTemplate->getTemplateParameters(), 830 /*Complain=*/true, 831 TPL_TemplateMatch)) 832 return true; 833 834 // C++ [temp.class]p4: 835 // In a redeclaration, partial specialization, explicit 836 // specialization or explicit instantiation of a class template, 837 // the class-key shall agree in kind with the original class 838 // template declaration (7.1.5.3). 839 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); 840 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) { 841 Diag(KWLoc, diag::err_use_with_wrong_tag) 842 << Name 843 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName()); 844 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); 845 Kind = PrevRecordDecl->getTagKind(); 846 } 847 848 // Check for redefinition of this class template. 849 if (TUK == TUK_Definition) { 850 if (TagDecl *Def = PrevRecordDecl->getDefinition()) { 851 Diag(NameLoc, diag::err_redefinition) << Name; 852 Diag(Def->getLocation(), diag::note_previous_definition); 853 // FIXME: Would it make sense to try to "forget" the previous 854 // definition, as part of error recovery? 855 return true; 856 } 857 } 858 } else if (PrevDecl && PrevDecl->isTemplateParameter()) { 859 // Maybe we will complain about the shadowed template parameter. 860 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 861 // Just pretend that we didn't see the previous declaration. 862 PrevDecl = 0; 863 } else if (PrevDecl) { 864 // C++ [temp]p5: 865 // A class template shall not have the same name as any other 866 // template, class, function, object, enumeration, enumerator, 867 // namespace, or type in the same scope (3.3), except as specified 868 // in (14.5.4). 869 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 870 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 871 return true; 872 } 873 874 // Check the template parameter list of this declaration, possibly 875 // merging in the template parameter list from the previous class 876 // template declaration. 877 if (CheckTemplateParameterList(TemplateParams, 878 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0, 879 TPC_ClassTemplate)) 880 Invalid = true; 881 882 if (SS.isSet()) { 883 // If the name of the template was qualified, we must be defining the 884 // template out-of-line. 885 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate && 886 !(TUK == TUK_Friend && CurContext->isDependentContext())) 887 Diag(NameLoc, diag::err_member_def_does_not_match) 888 << Name << SemanticContext << SS.getRange(); 889 } 890 891 CXXRecordDecl *NewClass = 892 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc, 893 PrevClassTemplate? 894 PrevClassTemplate->getTemplatedDecl() : 0, 895 /*DelayTypeCreation=*/true); 896 SetNestedNameSpecifier(NewClass, SS); 897 898 ClassTemplateDecl *NewTemplate 899 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, 900 DeclarationName(Name), TemplateParams, 901 NewClass, PrevClassTemplate); 902 NewClass->setDescribedClassTemplate(NewTemplate); 903 904 // Build the type for the class template declaration now. 905 QualType T = NewTemplate->getInjectedClassNameSpecialization(); 906 T = Context.getInjectedClassNameType(NewClass, T); 907 assert(T->isDependentType() && "Class template type is not dependent?"); 908 (void)T; 909 910 // If we are providing an explicit specialization of a member that is a 911 // class template, make a note of that. 912 if (PrevClassTemplate && 913 PrevClassTemplate->getInstantiatedFromMemberTemplate()) 914 PrevClassTemplate->setMemberSpecialization(); 915 916 // Set the access specifier. 917 if (!Invalid && TUK != TUK_Friend) 918 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); 919 920 // Set the lexical context of these templates 921 NewClass->setLexicalDeclContext(CurContext); 922 NewTemplate->setLexicalDeclContext(CurContext); 923 924 if (TUK == TUK_Definition) 925 NewClass->startDefinition(); 926 927 if (Attr) 928 ProcessDeclAttributeList(S, NewClass, Attr); 929 930 if (TUK != TUK_Friend) 931 PushOnScopeChains(NewTemplate, S); 932 else { 933 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { 934 NewTemplate->setAccess(PrevClassTemplate->getAccess()); 935 NewClass->setAccess(PrevClassTemplate->getAccess()); 936 } 937 938 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ 939 PrevClassTemplate != NULL); 940 941 // Friend templates are visible in fairly strange ways. 942 if (!CurContext->isDependentContext()) { 943 DeclContext *DC = SemanticContext->getRedeclContext(); 944 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false); 945 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 946 PushOnScopeChains(NewTemplate, EnclosingScope, 947 /* AddToContext = */ false); 948 } 949 950 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 951 NewClass->getLocation(), 952 NewTemplate, 953 /*FIXME:*/NewClass->getLocation()); 954 Friend->setAccess(AS_public); 955 CurContext->addDecl(Friend); 956 } 957 958 if (Invalid) { 959 NewTemplate->setInvalidDecl(); 960 NewClass->setInvalidDecl(); 961 } 962 return NewTemplate; 963} 964 965/// \brief Diagnose the presence of a default template argument on a 966/// template parameter, which is ill-formed in certain contexts. 967/// 968/// \returns true if the default template argument should be dropped. 969static bool DiagnoseDefaultTemplateArgument(Sema &S, 970 Sema::TemplateParamListContext TPC, 971 SourceLocation ParamLoc, 972 SourceRange DefArgRange) { 973 switch (TPC) { 974 case Sema::TPC_ClassTemplate: 975 return false; 976 977 case Sema::TPC_FunctionTemplate: 978 // C++ [temp.param]p9: 979 // A default template-argument shall not be specified in a 980 // function template declaration or a function template 981 // definition [...] 982 // (This sentence is not in C++0x, per DR226). 983 if (!S.getLangOptions().CPlusPlus0x) 984 S.Diag(ParamLoc, 985 diag::err_template_parameter_default_in_function_template) 986 << DefArgRange; 987 return false; 988 989 case Sema::TPC_ClassTemplateMember: 990 // C++0x [temp.param]p9: 991 // A default template-argument shall not be specified in the 992 // template-parameter-lists of the definition of a member of a 993 // class template that appears outside of the member's class. 994 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member) 995 << DefArgRange; 996 return true; 997 998 case Sema::TPC_FriendFunctionTemplate: 999 // C++ [temp.param]p9: 1000 // A default template-argument shall not be specified in a 1001 // friend template declaration. 1002 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template) 1003 << DefArgRange; 1004 return true; 1005 1006 // FIXME: C++0x [temp.param]p9 allows default template-arguments 1007 // for friend function templates if there is only a single 1008 // declaration (and it is a definition). Strange! 1009 } 1010 1011 return false; 1012} 1013 1014/// \brief Checks the validity of a template parameter list, possibly 1015/// considering the template parameter list from a previous 1016/// declaration. 1017/// 1018/// If an "old" template parameter list is provided, it must be 1019/// equivalent (per TemplateParameterListsAreEqual) to the "new" 1020/// template parameter list. 1021/// 1022/// \param NewParams Template parameter list for a new template 1023/// declaration. This template parameter list will be updated with any 1024/// default arguments that are carried through from the previous 1025/// template parameter list. 1026/// 1027/// \param OldParams If provided, template parameter list from a 1028/// previous declaration of the same template. Default template 1029/// arguments will be merged from the old template parameter list to 1030/// the new template parameter list. 1031/// 1032/// \param TPC Describes the context in which we are checking the given 1033/// template parameter list. 1034/// 1035/// \returns true if an error occurred, false otherwise. 1036bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, 1037 TemplateParameterList *OldParams, 1038 TemplateParamListContext TPC) { 1039 bool Invalid = false; 1040 1041 // C++ [temp.param]p10: 1042 // The set of default template-arguments available for use with a 1043 // template declaration or definition is obtained by merging the 1044 // default arguments from the definition (if in scope) and all 1045 // declarations in scope in the same way default function 1046 // arguments are (8.3.6). 1047 bool SawDefaultArgument = false; 1048 SourceLocation PreviousDefaultArgLoc; 1049 1050 bool SawParameterPack = false; 1051 SourceLocation ParameterPackLoc; 1052 1053 // Dummy initialization to avoid warnings. 1054 TemplateParameterList::iterator OldParam = NewParams->end(); 1055 if (OldParams) 1056 OldParam = OldParams->begin(); 1057 1058 for (TemplateParameterList::iterator NewParam = NewParams->begin(), 1059 NewParamEnd = NewParams->end(); 1060 NewParam != NewParamEnd; ++NewParam) { 1061 // Variables used to diagnose redundant default arguments 1062 bool RedundantDefaultArg = false; 1063 SourceLocation OldDefaultLoc; 1064 SourceLocation NewDefaultLoc; 1065 1066 // Variables used to diagnose missing default arguments 1067 bool MissingDefaultArg = false; 1068 1069 // C++0x [temp.param]p11: 1070 // If a template parameter of a class template is a template parameter pack, 1071 // it must be the last template parameter. 1072 if (SawParameterPack) { 1073 Diag(ParameterPackLoc, 1074 diag::err_template_param_pack_must_be_last_template_parameter); 1075 Invalid = true; 1076 } 1077 1078 if (TemplateTypeParmDecl *NewTypeParm 1079 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { 1080 // Check the presence of a default argument here. 1081 if (NewTypeParm->hasDefaultArgument() && 1082 DiagnoseDefaultTemplateArgument(*this, TPC, 1083 NewTypeParm->getLocation(), 1084 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc() 1085 .getSourceRange())) 1086 NewTypeParm->removeDefaultArgument(); 1087 1088 // Merge default arguments for template type parameters. 1089 TemplateTypeParmDecl *OldTypeParm 1090 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; 1091 1092 if (NewTypeParm->isParameterPack()) { 1093 assert(!NewTypeParm->hasDefaultArgument() && 1094 "Parameter packs can't have a default argument!"); 1095 SawParameterPack = true; 1096 ParameterPackLoc = NewTypeParm->getLocation(); 1097 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && 1098 NewTypeParm->hasDefaultArgument()) { 1099 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); 1100 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); 1101 SawDefaultArgument = true; 1102 RedundantDefaultArg = true; 1103 PreviousDefaultArgLoc = NewDefaultLoc; 1104 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { 1105 // Merge the default argument from the old declaration to the 1106 // new declaration. 1107 SawDefaultArgument = true; 1108 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), 1109 true); 1110 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); 1111 } else if (NewTypeParm->hasDefaultArgument()) { 1112 SawDefaultArgument = true; 1113 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); 1114 } else if (SawDefaultArgument) 1115 MissingDefaultArg = true; 1116 } else if (NonTypeTemplateParmDecl *NewNonTypeParm 1117 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { 1118 // Check the presence of a default argument here. 1119 if (NewNonTypeParm->hasDefaultArgument() && 1120 DiagnoseDefaultTemplateArgument(*this, TPC, 1121 NewNonTypeParm->getLocation(), 1122 NewNonTypeParm->getDefaultArgument()->getSourceRange())) { 1123 NewNonTypeParm->removeDefaultArgument(); 1124 } 1125 1126 // Merge default arguments for non-type template parameters 1127 NonTypeTemplateParmDecl *OldNonTypeParm 1128 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; 1129 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && 1130 NewNonTypeParm->hasDefaultArgument()) { 1131 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1132 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1133 SawDefaultArgument = true; 1134 RedundantDefaultArg = true; 1135 PreviousDefaultArgLoc = NewDefaultLoc; 1136 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { 1137 // Merge the default argument from the old declaration to the 1138 // new declaration. 1139 SawDefaultArgument = true; 1140 // FIXME: We need to create a new kind of "default argument" 1141 // expression that points to a previous template template 1142 // parameter. 1143 NewNonTypeParm->setDefaultArgument( 1144 OldNonTypeParm->getDefaultArgument(), 1145 /*Inherited=*/ true); 1146 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1147 } else if (NewNonTypeParm->hasDefaultArgument()) { 1148 SawDefaultArgument = true; 1149 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1150 } else if (SawDefaultArgument) 1151 MissingDefaultArg = true; 1152 } else { 1153 // Check the presence of a default argument here. 1154 TemplateTemplateParmDecl *NewTemplateParm 1155 = cast<TemplateTemplateParmDecl>(*NewParam); 1156 if (NewTemplateParm->hasDefaultArgument() && 1157 DiagnoseDefaultTemplateArgument(*this, TPC, 1158 NewTemplateParm->getLocation(), 1159 NewTemplateParm->getDefaultArgument().getSourceRange())) 1160 NewTemplateParm->removeDefaultArgument(); 1161 1162 // Merge default arguments for template template parameters 1163 TemplateTemplateParmDecl *OldTemplateParm 1164 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; 1165 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && 1166 NewTemplateParm->hasDefaultArgument()) { 1167 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); 1168 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); 1169 SawDefaultArgument = true; 1170 RedundantDefaultArg = true; 1171 PreviousDefaultArgLoc = NewDefaultLoc; 1172 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { 1173 // Merge the default argument from the old declaration to the 1174 // new declaration. 1175 SawDefaultArgument = true; 1176 // FIXME: We need to create a new kind of "default argument" expression 1177 // that points to a previous template template parameter. 1178 NewTemplateParm->setDefaultArgument( 1179 OldTemplateParm->getDefaultArgument(), 1180 /*Inherited=*/ true); 1181 PreviousDefaultArgLoc 1182 = OldTemplateParm->getDefaultArgument().getLocation(); 1183 } else if (NewTemplateParm->hasDefaultArgument()) { 1184 SawDefaultArgument = true; 1185 PreviousDefaultArgLoc 1186 = NewTemplateParm->getDefaultArgument().getLocation(); 1187 } else if (SawDefaultArgument) 1188 MissingDefaultArg = true; 1189 } 1190 1191 if (RedundantDefaultArg) { 1192 // C++ [temp.param]p12: 1193 // A template-parameter shall not be given default arguments 1194 // by two different declarations in the same scope. 1195 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); 1196 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); 1197 Invalid = true; 1198 } else if (MissingDefaultArg) { 1199 // C++ [temp.param]p11: 1200 // If a template-parameter has a default template-argument, 1201 // all subsequent template-parameters shall have a default 1202 // template-argument supplied. 1203 Diag((*NewParam)->getLocation(), 1204 diag::err_template_param_default_arg_missing); 1205 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); 1206 Invalid = true; 1207 } 1208 1209 // If we have an old template parameter list that we're merging 1210 // in, move on to the next parameter. 1211 if (OldParams) 1212 ++OldParam; 1213 } 1214 1215 return Invalid; 1216} 1217 1218/// \brief Match the given template parameter lists to the given scope 1219/// specifier, returning the template parameter list that applies to the 1220/// name. 1221/// 1222/// \param DeclStartLoc the start of the declaration that has a scope 1223/// specifier or a template parameter list. 1224/// 1225/// \param SS the scope specifier that will be matched to the given template 1226/// parameter lists. This scope specifier precedes a qualified name that is 1227/// being declared. 1228/// 1229/// \param ParamLists the template parameter lists, from the outermost to the 1230/// innermost template parameter lists. 1231/// 1232/// \param NumParamLists the number of template parameter lists in ParamLists. 1233/// 1234/// \param IsFriend Whether to apply the slightly different rules for 1235/// matching template parameters to scope specifiers in friend 1236/// declarations. 1237/// 1238/// \param IsExplicitSpecialization will be set true if the entity being 1239/// declared is an explicit specialization, false otherwise. 1240/// 1241/// \returns the template parameter list, if any, that corresponds to the 1242/// name that is preceded by the scope specifier @p SS. This template 1243/// parameter list may be have template parameters (if we're declaring a 1244/// template) or may have no template parameters (if we're declaring a 1245/// template specialization), or may be NULL (if we were's declaring isn't 1246/// itself a template). 1247TemplateParameterList * 1248Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, 1249 const CXXScopeSpec &SS, 1250 TemplateParameterList **ParamLists, 1251 unsigned NumParamLists, 1252 bool IsFriend, 1253 bool &IsExplicitSpecialization, 1254 bool &Invalid) { 1255 IsExplicitSpecialization = false; 1256 1257 // Find the template-ids that occur within the nested-name-specifier. These 1258 // template-ids will match up with the template parameter lists. 1259 llvm::SmallVector<const TemplateSpecializationType *, 4> 1260 TemplateIdsInSpecifier; 1261 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4> 1262 ExplicitSpecializationsInSpecifier; 1263 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 1264 NNS; NNS = NNS->getPrefix()) { 1265 const Type *T = NNS->getAsType(); 1266 if (!T) break; 1267 1268 // C++0x [temp.expl.spec]p17: 1269 // A member or a member template may be nested within many 1270 // enclosing class templates. In an explicit specialization for 1271 // such a member, the member declaration shall be preceded by a 1272 // template<> for each enclosing class template that is 1273 // explicitly specialized. 1274 // 1275 // Following the existing practice of GNU and EDG, we allow a typedef of a 1276 // template specialization type. 1277 if (const TypedefType *TT = dyn_cast<TypedefType>(T)) 1278 T = TT->LookThroughTypedefs().getTypePtr(); 1279 1280 if (const TemplateSpecializationType *SpecType 1281 = dyn_cast<TemplateSpecializationType>(T)) { 1282 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl(); 1283 if (!Template) 1284 continue; // FIXME: should this be an error? probably... 1285 1286 if (const RecordType *Record = SpecType->getAs<RecordType>()) { 1287 ClassTemplateSpecializationDecl *SpecDecl 1288 = cast<ClassTemplateSpecializationDecl>(Record->getDecl()); 1289 // If the nested name specifier refers to an explicit specialization, 1290 // we don't need a template<> header. 1291 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) { 1292 ExplicitSpecializationsInSpecifier.push_back(SpecDecl); 1293 continue; 1294 } 1295 } 1296 1297 TemplateIdsInSpecifier.push_back(SpecType); 1298 } 1299 } 1300 1301 // Reverse the list of template-ids in the scope specifier, so that we can 1302 // more easily match up the template-ids and the template parameter lists. 1303 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end()); 1304 1305 SourceLocation FirstTemplateLoc = DeclStartLoc; 1306 if (NumParamLists) 1307 FirstTemplateLoc = ParamLists[0]->getTemplateLoc(); 1308 1309 // Match the template-ids found in the specifier to the template parameter 1310 // lists. 1311 unsigned Idx = 0; 1312 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size(); 1313 Idx != NumTemplateIds; ++Idx) { 1314 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0); 1315 bool DependentTemplateId = TemplateId->isDependentType(); 1316 if (Idx >= NumParamLists) { 1317 // We have a template-id without a corresponding template parameter 1318 // list. 1319 1320 // ...which is fine if this is a friend declaration. 1321 if (IsFriend) { 1322 IsExplicitSpecialization = true; 1323 break; 1324 } 1325 1326 if (DependentTemplateId) { 1327 // FIXME: the location information here isn't great. 1328 Diag(SS.getRange().getBegin(), 1329 diag::err_template_spec_needs_template_parameters) 1330 << TemplateId 1331 << SS.getRange(); 1332 Invalid = true; 1333 } else { 1334 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header) 1335 << SS.getRange() 1336 << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> "); 1337 IsExplicitSpecialization = true; 1338 } 1339 return 0; 1340 } 1341 1342 // Check the template parameter list against its corresponding template-id. 1343 if (DependentTemplateId) { 1344 TemplateParameterList *ExpectedTemplateParams = 0; 1345 1346 // Are there cases in (e.g.) friends where this won't match? 1347 if (const InjectedClassNameType *Injected 1348 = TemplateId->getAs<InjectedClassNameType>()) { 1349 CXXRecordDecl *Record = Injected->getDecl(); 1350 if (ClassTemplatePartialSpecializationDecl *Partial = 1351 dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) 1352 ExpectedTemplateParams = Partial->getTemplateParameters(); 1353 else 1354 ExpectedTemplateParams = Record->getDescribedClassTemplate() 1355 ->getTemplateParameters(); 1356 } 1357 1358 if (ExpectedTemplateParams) 1359 TemplateParameterListsAreEqual(ParamLists[Idx], 1360 ExpectedTemplateParams, 1361 true, TPL_TemplateMatch); 1362 1363 CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember); 1364 } else if (ParamLists[Idx]->size() > 0) 1365 Diag(ParamLists[Idx]->getTemplateLoc(), 1366 diag::err_template_param_list_matches_nontemplate) 1367 << TemplateId 1368 << ParamLists[Idx]->getSourceRange(); 1369 else 1370 IsExplicitSpecialization = true; 1371 } 1372 1373 // If there were at least as many template-ids as there were template 1374 // parameter lists, then there are no template parameter lists remaining for 1375 // the declaration itself. 1376 if (Idx >= NumParamLists) 1377 return 0; 1378 1379 // If there were too many template parameter lists, complain about that now. 1380 if (Idx != NumParamLists - 1) { 1381 while (Idx < NumParamLists - 1) { 1382 bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0; 1383 Diag(ParamLists[Idx]->getTemplateLoc(), 1384 isExplicitSpecHeader? diag::warn_template_spec_extra_headers 1385 : diag::err_template_spec_extra_headers) 1386 << SourceRange(ParamLists[Idx]->getTemplateLoc(), 1387 ParamLists[Idx]->getRAngleLoc()); 1388 1389 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) { 1390 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(), 1391 diag::note_explicit_template_spec_does_not_need_header) 1392 << ExplicitSpecializationsInSpecifier.back(); 1393 ExplicitSpecializationsInSpecifier.pop_back(); 1394 } 1395 1396 // We have a template parameter list with no corresponding scope, which 1397 // means that the resulting template declaration can't be instantiated 1398 // properly (we'll end up with dependent nodes when we shouldn't). 1399 if (!isExplicitSpecHeader) 1400 Invalid = true; 1401 1402 ++Idx; 1403 } 1404 } 1405 1406 // Return the last template parameter list, which corresponds to the 1407 // entity being declared. 1408 return ParamLists[NumParamLists - 1]; 1409} 1410 1411QualType Sema::CheckTemplateIdType(TemplateName Name, 1412 SourceLocation TemplateLoc, 1413 const TemplateArgumentListInfo &TemplateArgs) { 1414 TemplateDecl *Template = Name.getAsTemplateDecl(); 1415 if (!Template) { 1416 // The template name does not resolve to a template, so we just 1417 // build a dependent template-id type. 1418 return Context.getTemplateSpecializationType(Name, TemplateArgs); 1419 } 1420 1421 // Check that the template argument list is well-formed for this 1422 // template. 1423 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(), 1424 TemplateArgs.size()); 1425 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs, 1426 false, Converted)) 1427 return QualType(); 1428 1429 assert((Converted.structuredSize() == 1430 Template->getTemplateParameters()->size()) && 1431 "Converted template argument list is too short!"); 1432 1433 QualType CanonType; 1434 1435 if (Name.isDependent() || 1436 TemplateSpecializationType::anyDependentTemplateArguments( 1437 TemplateArgs)) { 1438 // This class template specialization is a dependent 1439 // type. Therefore, its canonical type is another class template 1440 // specialization type that contains all of the converted 1441 // arguments in canonical form. This ensures that, e.g., A<T> and 1442 // A<T, T> have identical types when A is declared as: 1443 // 1444 // template<typename T, typename U = T> struct A; 1445 TemplateName CanonName = Context.getCanonicalTemplateName(Name); 1446 CanonType = Context.getTemplateSpecializationType(CanonName, 1447 Converted.getFlatArguments(), 1448 Converted.flatSize()); 1449 1450 // FIXME: CanonType is not actually the canonical type, and unfortunately 1451 // it is a TemplateSpecializationType that we will never use again. 1452 // In the future, we need to teach getTemplateSpecializationType to only 1453 // build the canonical type and return that to us. 1454 CanonType = Context.getCanonicalType(CanonType); 1455 1456 // This might work out to be a current instantiation, in which 1457 // case the canonical type needs to be the InjectedClassNameType. 1458 // 1459 // TODO: in theory this could be a simple hashtable lookup; most 1460 // changes to CurContext don't change the set of current 1461 // instantiations. 1462 if (isa<ClassTemplateDecl>(Template)) { 1463 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) { 1464 // If we get out to a namespace, we're done. 1465 if (Ctx->isFileContext()) break; 1466 1467 // If this isn't a record, keep looking. 1468 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx); 1469 if (!Record) continue; 1470 1471 // Look for one of the two cases with InjectedClassNameTypes 1472 // and check whether it's the same template. 1473 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) && 1474 !Record->getDescribedClassTemplate()) 1475 continue; 1476 1477 // Fetch the injected class name type and check whether its 1478 // injected type is equal to the type we just built. 1479 QualType ICNT = Context.getTypeDeclType(Record); 1480 QualType Injected = cast<InjectedClassNameType>(ICNT) 1481 ->getInjectedSpecializationType(); 1482 1483 if (CanonType != Injected->getCanonicalTypeInternal()) 1484 continue; 1485 1486 // If so, the canonical type of this TST is the injected 1487 // class name type of the record we just found. 1488 assert(ICNT.isCanonical()); 1489 CanonType = ICNT; 1490 break; 1491 } 1492 } 1493 } else if (ClassTemplateDecl *ClassTemplate 1494 = dyn_cast<ClassTemplateDecl>(Template)) { 1495 // Find the class template specialization declaration that 1496 // corresponds to these arguments. 1497 void *InsertPos = 0; 1498 ClassTemplateSpecializationDecl *Decl 1499 = ClassTemplate->findSpecialization(Converted.getFlatArguments(), 1500 Converted.flatSize(), InsertPos); 1501 if (!Decl) { 1502 // This is the first time we have referenced this class template 1503 // specialization. Create the canonical declaration and add it to 1504 // the set of specializations. 1505 Decl = ClassTemplateSpecializationDecl::Create(Context, 1506 ClassTemplate->getTemplatedDecl()->getTagKind(), 1507 ClassTemplate->getDeclContext(), 1508 ClassTemplate->getLocation(), 1509 ClassTemplate, 1510 Converted, 0); 1511 ClassTemplate->AddSpecialization(Decl, InsertPos); 1512 Decl->setLexicalDeclContext(CurContext); 1513 } 1514 1515 CanonType = Context.getTypeDeclType(Decl); 1516 assert(isa<RecordType>(CanonType) && 1517 "type of non-dependent specialization is not a RecordType"); 1518 } 1519 1520 // Build the fully-sugared type for this class template 1521 // specialization, which refers back to the class template 1522 // specialization we created or found. 1523 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); 1524} 1525 1526TypeResult 1527Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc, 1528 SourceLocation LAngleLoc, 1529 ASTTemplateArgsPtr TemplateArgsIn, 1530 SourceLocation RAngleLoc) { 1531 TemplateName Template = TemplateD.getAsVal<TemplateName>(); 1532 1533 // Translate the parser's template argument list in our AST format. 1534 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 1535 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 1536 1537 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); 1538 TemplateArgsIn.release(); 1539 1540 if (Result.isNull()) 1541 return true; 1542 1543 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result); 1544 TemplateSpecializationTypeLoc TL 1545 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc()); 1546 TL.setTemplateNameLoc(TemplateLoc); 1547 TL.setLAngleLoc(LAngleLoc); 1548 TL.setRAngleLoc(RAngleLoc); 1549 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) 1550 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); 1551 1552 return CreateParsedType(Result, DI); 1553} 1554 1555TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult, 1556 TagUseKind TUK, 1557 TypeSpecifierType TagSpec, 1558 SourceLocation TagLoc) { 1559 if (TypeResult.isInvalid()) 1560 return ::TypeResult(); 1561 1562 // FIXME: preserve source info, ideally without copying the DI. 1563 TypeSourceInfo *DI; 1564 QualType Type = GetTypeFromParser(TypeResult.get(), &DI); 1565 1566 // Verify the tag specifier. 1567 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 1568 1569 if (const RecordType *RT = Type->getAs<RecordType>()) { 1570 RecordDecl *D = RT->getDecl(); 1571 1572 IdentifierInfo *Id = D->getIdentifier(); 1573 assert(Id && "templated class must have an identifier"); 1574 1575 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) { 1576 Diag(TagLoc, diag::err_use_with_wrong_tag) 1577 << Type 1578 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName()); 1579 Diag(D->getLocation(), diag::note_previous_use); 1580 } 1581 } 1582 1583 ElaboratedTypeKeyword Keyword 1584 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind); 1585 QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type); 1586 1587 return ParsedType::make(ElabType); 1588} 1589 1590ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS, 1591 LookupResult &R, 1592 bool RequiresADL, 1593 const TemplateArgumentListInfo &TemplateArgs) { 1594 // FIXME: Can we do any checking at this point? I guess we could check the 1595 // template arguments that we have against the template name, if the template 1596 // name refers to a single template. That's not a terribly common case, 1597 // though. 1598 1599 // These should be filtered out by our callers. 1600 assert(!R.empty() && "empty lookup results when building templateid"); 1601 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid"); 1602 1603 NestedNameSpecifier *Qualifier = 0; 1604 SourceRange QualifierRange; 1605 if (SS.isSet()) { 1606 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 1607 QualifierRange = SS.getRange(); 1608 } 1609 1610 // We don't want lookup warnings at this point. 1611 R.suppressDiagnostics(); 1612 1613 bool Dependent 1614 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 1615 &TemplateArgs); 1616 UnresolvedLookupExpr *ULE 1617 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1618 Qualifier, QualifierRange, 1619 R.getLookupNameInfo(), 1620 RequiresADL, TemplateArgs, 1621 R.begin(), R.end()); 1622 1623 return Owned(ULE); 1624} 1625 1626// We actually only call this from template instantiation. 1627ExprResult 1628Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS, 1629 const DeclarationNameInfo &NameInfo, 1630 const TemplateArgumentListInfo &TemplateArgs) { 1631 DeclContext *DC; 1632 if (!(DC = computeDeclContext(SS, false)) || 1633 DC->isDependentContext() || 1634 RequireCompleteDeclContext(SS, DC)) 1635 return BuildDependentDeclRefExpr(SS, NameInfo, &TemplateArgs); 1636 1637 bool MemberOfUnknownSpecialization; 1638 LookupResult R(*this, NameInfo, LookupOrdinaryName); 1639 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false, 1640 MemberOfUnknownSpecialization); 1641 1642 if (R.isAmbiguous()) 1643 return ExprError(); 1644 1645 if (R.empty()) { 1646 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_non_template) 1647 << NameInfo.getName() << SS.getRange(); 1648 return ExprError(); 1649 } 1650 1651 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) { 1652 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template) 1653 << (NestedNameSpecifier*) SS.getScopeRep() 1654 << NameInfo.getName() << SS.getRange(); 1655 Diag(Temp->getLocation(), diag::note_referenced_class_template); 1656 return ExprError(); 1657 } 1658 1659 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs); 1660} 1661 1662/// \brief Form a dependent template name. 1663/// 1664/// This action forms a dependent template name given the template 1665/// name and its (presumably dependent) scope specifier. For 1666/// example, given "MetaFun::template apply", the scope specifier \p 1667/// SS will be "MetaFun::", \p TemplateKWLoc contains the location 1668/// of the "template" keyword, and "apply" is the \p Name. 1669TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S, 1670 SourceLocation TemplateKWLoc, 1671 CXXScopeSpec &SS, 1672 UnqualifiedId &Name, 1673 ParsedType ObjectType, 1674 bool EnteringContext, 1675 TemplateTy &Result) { 1676 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent() && 1677 !getLangOptions().CPlusPlus0x) 1678 Diag(TemplateKWLoc, diag::ext_template_outside_of_template) 1679 << FixItHint::CreateRemoval(TemplateKWLoc); 1680 1681 DeclContext *LookupCtx = 0; 1682 if (SS.isSet()) 1683 LookupCtx = computeDeclContext(SS, EnteringContext); 1684 if (!LookupCtx && ObjectType) 1685 LookupCtx = computeDeclContext(ObjectType.get()); 1686 if (LookupCtx) { 1687 // C++0x [temp.names]p5: 1688 // If a name prefixed by the keyword template is not the name of 1689 // a template, the program is ill-formed. [Note: the keyword 1690 // template may not be applied to non-template members of class 1691 // templates. -end note ] [ Note: as is the case with the 1692 // typename prefix, the template prefix is allowed in cases 1693 // where it is not strictly necessary; i.e., when the 1694 // nested-name-specifier or the expression on the left of the -> 1695 // or . is not dependent on a template-parameter, or the use 1696 // does not appear in the scope of a template. -end note] 1697 // 1698 // Note: C++03 was more strict here, because it banned the use of 1699 // the "template" keyword prior to a template-name that was not a 1700 // dependent name. C++ DR468 relaxed this requirement (the 1701 // "template" keyword is now permitted). We follow the C++0x 1702 // rules, even in C++03 mode with a warning, retroactively applying the DR. 1703 bool MemberOfUnknownSpecialization; 1704 TemplateNameKind TNK = isTemplateName(0, SS, TemplateKWLoc.isValid(), Name, 1705 ObjectType, EnteringContext, Result, 1706 MemberOfUnknownSpecialization); 1707 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() && 1708 isa<CXXRecordDecl>(LookupCtx) && 1709 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) { 1710 // This is a dependent template. Handle it below. 1711 } else if (TNK == TNK_Non_template) { 1712 Diag(Name.getSourceRange().getBegin(), 1713 diag::err_template_kw_refers_to_non_template) 1714 << GetNameFromUnqualifiedId(Name).getName() 1715 << Name.getSourceRange() 1716 << TemplateKWLoc; 1717 return TNK_Non_template; 1718 } else { 1719 // We found something; return it. 1720 return TNK; 1721 } 1722 } 1723 1724 NestedNameSpecifier *Qualifier 1725 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1726 1727 switch (Name.getKind()) { 1728 case UnqualifiedId::IK_Identifier: 1729 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1730 Name.Identifier)); 1731 return TNK_Dependent_template_name; 1732 1733 case UnqualifiedId::IK_OperatorFunctionId: 1734 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1735 Name.OperatorFunctionId.Operator)); 1736 return TNK_Dependent_template_name; 1737 1738 case UnqualifiedId::IK_LiteralOperatorId: 1739 assert(false && "We don't support these; Parse shouldn't have allowed propagation"); 1740 1741 default: 1742 break; 1743 } 1744 1745 Diag(Name.getSourceRange().getBegin(), 1746 diag::err_template_kw_refers_to_non_template) 1747 << GetNameFromUnqualifiedId(Name).getName() 1748 << Name.getSourceRange() 1749 << TemplateKWLoc; 1750 return TNK_Non_template; 1751} 1752 1753bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, 1754 const TemplateArgumentLoc &AL, 1755 TemplateArgumentListBuilder &Converted) { 1756 const TemplateArgument &Arg = AL.getArgument(); 1757 1758 // Check template type parameter. 1759 switch(Arg.getKind()) { 1760 case TemplateArgument::Type: 1761 // C++ [temp.arg.type]p1: 1762 // A template-argument for a template-parameter which is a 1763 // type shall be a type-id. 1764 break; 1765 case TemplateArgument::Template: { 1766 // We have a template type parameter but the template argument 1767 // is a template without any arguments. 1768 SourceRange SR = AL.getSourceRange(); 1769 TemplateName Name = Arg.getAsTemplate(); 1770 Diag(SR.getBegin(), diag::err_template_missing_args) 1771 << Name << SR; 1772 if (TemplateDecl *Decl = Name.getAsTemplateDecl()) 1773 Diag(Decl->getLocation(), diag::note_template_decl_here); 1774 1775 return true; 1776 } 1777 default: { 1778 // We have a template type parameter but the template argument 1779 // is not a type. 1780 SourceRange SR = AL.getSourceRange(); 1781 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; 1782 Diag(Param->getLocation(), diag::note_template_param_here); 1783 1784 return true; 1785 } 1786 } 1787 1788 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo())) 1789 return true; 1790 1791 // Add the converted template type argument. 1792 Converted.Append( 1793 TemplateArgument(Context.getCanonicalType(Arg.getAsType()))); 1794 return false; 1795} 1796 1797/// \brief Substitute template arguments into the default template argument for 1798/// the given template type parameter. 1799/// 1800/// \param SemaRef the semantic analysis object for which we are performing 1801/// the substitution. 1802/// 1803/// \param Template the template that we are synthesizing template arguments 1804/// for. 1805/// 1806/// \param TemplateLoc the location of the template name that started the 1807/// template-id we are checking. 1808/// 1809/// \param RAngleLoc the location of the right angle bracket ('>') that 1810/// terminates the template-id. 1811/// 1812/// \param Param the template template parameter whose default we are 1813/// substituting into. 1814/// 1815/// \param Converted the list of template arguments provided for template 1816/// parameters that precede \p Param in the template parameter list. 1817/// 1818/// \returns the substituted template argument, or NULL if an error occurred. 1819static TypeSourceInfo * 1820SubstDefaultTemplateArgument(Sema &SemaRef, 1821 TemplateDecl *Template, 1822 SourceLocation TemplateLoc, 1823 SourceLocation RAngleLoc, 1824 TemplateTypeParmDecl *Param, 1825 TemplateArgumentListBuilder &Converted) { 1826 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo(); 1827 1828 // If the argument type is dependent, instantiate it now based 1829 // on the previously-computed template arguments. 1830 if (ArgType->getType()->isDependentType()) { 1831 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1832 /*TakeArgs=*/false); 1833 1834 MultiLevelTemplateArgumentList AllTemplateArgs 1835 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1836 1837 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1838 Template, Converted.getFlatArguments(), 1839 Converted.flatSize(), 1840 SourceRange(TemplateLoc, RAngleLoc)); 1841 1842 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, 1843 Param->getDefaultArgumentLoc(), 1844 Param->getDeclName()); 1845 } 1846 1847 return ArgType; 1848} 1849 1850/// \brief Substitute template arguments into the default template argument for 1851/// the given non-type template parameter. 1852/// 1853/// \param SemaRef the semantic analysis object for which we are performing 1854/// the substitution. 1855/// 1856/// \param Template the template that we are synthesizing template arguments 1857/// for. 1858/// 1859/// \param TemplateLoc the location of the template name that started the 1860/// template-id we are checking. 1861/// 1862/// \param RAngleLoc the location of the right angle bracket ('>') that 1863/// terminates the template-id. 1864/// 1865/// \param Param the non-type template parameter whose default we are 1866/// substituting into. 1867/// 1868/// \param Converted the list of template arguments provided for template 1869/// parameters that precede \p Param in the template parameter list. 1870/// 1871/// \returns the substituted template argument, or NULL if an error occurred. 1872static ExprResult 1873SubstDefaultTemplateArgument(Sema &SemaRef, 1874 TemplateDecl *Template, 1875 SourceLocation TemplateLoc, 1876 SourceLocation RAngleLoc, 1877 NonTypeTemplateParmDecl *Param, 1878 TemplateArgumentListBuilder &Converted) { 1879 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1880 /*TakeArgs=*/false); 1881 1882 MultiLevelTemplateArgumentList AllTemplateArgs 1883 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1884 1885 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1886 Template, Converted.getFlatArguments(), 1887 Converted.flatSize(), 1888 SourceRange(TemplateLoc, RAngleLoc)); 1889 1890 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); 1891} 1892 1893/// \brief Substitute template arguments into the default template argument for 1894/// the given template template parameter. 1895/// 1896/// \param SemaRef the semantic analysis object for which we are performing 1897/// the substitution. 1898/// 1899/// \param Template the template that we are synthesizing template arguments 1900/// for. 1901/// 1902/// \param TemplateLoc the location of the template name that started the 1903/// template-id we are checking. 1904/// 1905/// \param RAngleLoc the location of the right angle bracket ('>') that 1906/// terminates the template-id. 1907/// 1908/// \param Param the template template parameter whose default we are 1909/// substituting into. 1910/// 1911/// \param Converted the list of template arguments provided for template 1912/// parameters that precede \p Param in the template parameter list. 1913/// 1914/// \returns the substituted template argument, or NULL if an error occurred. 1915static TemplateName 1916SubstDefaultTemplateArgument(Sema &SemaRef, 1917 TemplateDecl *Template, 1918 SourceLocation TemplateLoc, 1919 SourceLocation RAngleLoc, 1920 TemplateTemplateParmDecl *Param, 1921 TemplateArgumentListBuilder &Converted) { 1922 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1923 /*TakeArgs=*/false); 1924 1925 MultiLevelTemplateArgumentList AllTemplateArgs 1926 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1927 1928 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1929 Template, Converted.getFlatArguments(), 1930 Converted.flatSize(), 1931 SourceRange(TemplateLoc, RAngleLoc)); 1932 1933 return SemaRef.SubstTemplateName( 1934 Param->getDefaultArgument().getArgument().getAsTemplate(), 1935 Param->getDefaultArgument().getTemplateNameLoc(), 1936 AllTemplateArgs); 1937} 1938 1939/// \brief If the given template parameter has a default template 1940/// argument, substitute into that default template argument and 1941/// return the corresponding template argument. 1942TemplateArgumentLoc 1943Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template, 1944 SourceLocation TemplateLoc, 1945 SourceLocation RAngleLoc, 1946 Decl *Param, 1947 TemplateArgumentListBuilder &Converted) { 1948 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) { 1949 if (!TypeParm->hasDefaultArgument()) 1950 return TemplateArgumentLoc(); 1951 1952 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template, 1953 TemplateLoc, 1954 RAngleLoc, 1955 TypeParm, 1956 Converted); 1957 if (DI) 1958 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI); 1959 1960 return TemplateArgumentLoc(); 1961 } 1962 1963 if (NonTypeTemplateParmDecl *NonTypeParm 1964 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1965 if (!NonTypeParm->hasDefaultArgument()) 1966 return TemplateArgumentLoc(); 1967 1968 ExprResult Arg = SubstDefaultTemplateArgument(*this, Template, 1969 TemplateLoc, 1970 RAngleLoc, 1971 NonTypeParm, 1972 Converted); 1973 if (Arg.isInvalid()) 1974 return TemplateArgumentLoc(); 1975 1976 Expr *ArgE = Arg.takeAs<Expr>(); 1977 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE); 1978 } 1979 1980 TemplateTemplateParmDecl *TempTempParm 1981 = cast<TemplateTemplateParmDecl>(Param); 1982 if (!TempTempParm->hasDefaultArgument()) 1983 return TemplateArgumentLoc(); 1984 1985 TemplateName TName = SubstDefaultTemplateArgument(*this, Template, 1986 TemplateLoc, 1987 RAngleLoc, 1988 TempTempParm, 1989 Converted); 1990 if (TName.isNull()) 1991 return TemplateArgumentLoc(); 1992 1993 return TemplateArgumentLoc(TemplateArgument(TName), 1994 TempTempParm->getDefaultArgument().getTemplateQualifierRange(), 1995 TempTempParm->getDefaultArgument().getTemplateNameLoc()); 1996} 1997 1998/// \brief Check that the given template argument corresponds to the given 1999/// template parameter. 2000bool Sema::CheckTemplateArgument(NamedDecl *Param, 2001 const TemplateArgumentLoc &Arg, 2002 TemplateDecl *Template, 2003 SourceLocation TemplateLoc, 2004 SourceLocation RAngleLoc, 2005 TemplateArgumentListBuilder &Converted, 2006 CheckTemplateArgumentKind CTAK) { 2007 // Check template type parameters. 2008 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) 2009 return CheckTemplateTypeArgument(TTP, Arg, Converted); 2010 2011 // Check non-type template parameters. 2012 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { 2013 // Do substitution on the type of the non-type template parameter 2014 // with the template arguments we've seen thus far. 2015 QualType NTTPType = NTTP->getType(); 2016 if (NTTPType->isDependentType()) { 2017 // Do substitution on the type of the non-type template parameter. 2018 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2019 NTTP, Converted.getFlatArguments(), 2020 Converted.flatSize(), 2021 SourceRange(TemplateLoc, RAngleLoc)); 2022 2023 TemplateArgumentList TemplateArgs(Context, Converted, 2024 /*TakeArgs=*/false); 2025 NTTPType = SubstType(NTTPType, 2026 MultiLevelTemplateArgumentList(TemplateArgs), 2027 NTTP->getLocation(), 2028 NTTP->getDeclName()); 2029 // If that worked, check the non-type template parameter type 2030 // for validity. 2031 if (!NTTPType.isNull()) 2032 NTTPType = CheckNonTypeTemplateParameterType(NTTPType, 2033 NTTP->getLocation()); 2034 if (NTTPType.isNull()) 2035 return true; 2036 } 2037 2038 switch (Arg.getArgument().getKind()) { 2039 case TemplateArgument::Null: 2040 assert(false && "Should never see a NULL template argument here"); 2041 return true; 2042 2043 case TemplateArgument::Expression: { 2044 Expr *E = Arg.getArgument().getAsExpr(); 2045 TemplateArgument Result; 2046 if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK)) 2047 return true; 2048 2049 Converted.Append(Result); 2050 break; 2051 } 2052 2053 case TemplateArgument::Declaration: 2054 case TemplateArgument::Integral: 2055 // We've already checked this template argument, so just copy 2056 // it to the list of converted arguments. 2057 Converted.Append(Arg.getArgument()); 2058 break; 2059 2060 case TemplateArgument::Template: 2061 // We were given a template template argument. It may not be ill-formed; 2062 // see below. 2063 if (DependentTemplateName *DTN 2064 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) { 2065 // We have a template argument such as \c T::template X, which we 2066 // parsed as a template template argument. However, since we now 2067 // know that we need a non-type template argument, convert this 2068 // template name into an expression. 2069 2070 DeclarationNameInfo NameInfo(DTN->getIdentifier(), 2071 Arg.getTemplateNameLoc()); 2072 2073 Expr *E = DependentScopeDeclRefExpr::Create(Context, 2074 DTN->getQualifier(), 2075 Arg.getTemplateQualifierRange(), 2076 NameInfo); 2077 2078 TemplateArgument Result; 2079 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 2080 return true; 2081 2082 Converted.Append(Result); 2083 break; 2084 } 2085 2086 // We have a template argument that actually does refer to a class 2087 // template, template alias, or template template parameter, and 2088 // therefore cannot be a non-type template argument. 2089 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) 2090 << Arg.getSourceRange(); 2091 2092 Diag(Param->getLocation(), diag::note_template_param_here); 2093 return true; 2094 2095 case TemplateArgument::Type: { 2096 // We have a non-type template parameter but the template 2097 // argument is a type. 2098 2099 // C++ [temp.arg]p2: 2100 // In a template-argument, an ambiguity between a type-id and 2101 // an expression is resolved to a type-id, regardless of the 2102 // form of the corresponding template-parameter. 2103 // 2104 // We warn specifically about this case, since it can be rather 2105 // confusing for users. 2106 QualType T = Arg.getArgument().getAsType(); 2107 SourceRange SR = Arg.getSourceRange(); 2108 if (T->isFunctionType()) 2109 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; 2110 else 2111 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; 2112 Diag(Param->getLocation(), diag::note_template_param_here); 2113 return true; 2114 } 2115 2116 case TemplateArgument::Pack: 2117 llvm_unreachable("Caller must expand template argument packs"); 2118 break; 2119 } 2120 2121 return false; 2122 } 2123 2124 2125 // Check template template parameters. 2126 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); 2127 2128 // Substitute into the template parameter list of the template 2129 // template parameter, since previously-supplied template arguments 2130 // may appear within the template template parameter. 2131 { 2132 // Set up a template instantiation context. 2133 LocalInstantiationScope Scope(*this); 2134 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2135 TempParm, Converted.getFlatArguments(), 2136 Converted.flatSize(), 2137 SourceRange(TemplateLoc, RAngleLoc)); 2138 2139 TemplateArgumentList TemplateArgs(Context, Converted, 2140 /*TakeArgs=*/false); 2141 TempParm = cast_or_null<TemplateTemplateParmDecl>( 2142 SubstDecl(TempParm, CurContext, 2143 MultiLevelTemplateArgumentList(TemplateArgs))); 2144 if (!TempParm) 2145 return true; 2146 2147 // FIXME: TempParam is leaked. 2148 } 2149 2150 switch (Arg.getArgument().getKind()) { 2151 case TemplateArgument::Null: 2152 assert(false && "Should never see a NULL template argument here"); 2153 return true; 2154 2155 case TemplateArgument::Template: 2156 if (CheckTemplateArgument(TempParm, Arg)) 2157 return true; 2158 2159 Converted.Append(Arg.getArgument()); 2160 break; 2161 2162 case TemplateArgument::Expression: 2163 case TemplateArgument::Type: 2164 // We have a template template parameter but the template 2165 // argument does not refer to a template. 2166 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template); 2167 return true; 2168 2169 case TemplateArgument::Declaration: 2170 llvm_unreachable( 2171 "Declaration argument with template template parameter"); 2172 break; 2173 case TemplateArgument::Integral: 2174 llvm_unreachable( 2175 "Integral argument with template template parameter"); 2176 break; 2177 2178 case TemplateArgument::Pack: 2179 llvm_unreachable("Caller must expand template argument packs"); 2180 break; 2181 } 2182 2183 return false; 2184} 2185 2186/// \brief Check that the given template argument list is well-formed 2187/// for specializing the given template. 2188bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, 2189 SourceLocation TemplateLoc, 2190 const TemplateArgumentListInfo &TemplateArgs, 2191 bool PartialTemplateArgs, 2192 TemplateArgumentListBuilder &Converted) { 2193 TemplateParameterList *Params = Template->getTemplateParameters(); 2194 unsigned NumParams = Params->size(); 2195 unsigned NumArgs = TemplateArgs.size(); 2196 bool Invalid = false; 2197 2198 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc(); 2199 2200 bool HasParameterPack = 2201 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); 2202 2203 if ((NumArgs > NumParams && !HasParameterPack) || 2204 (NumArgs < Params->getMinRequiredArguments() && 2205 !PartialTemplateArgs)) { 2206 // FIXME: point at either the first arg beyond what we can handle, 2207 // or the '>', depending on whether we have too many or too few 2208 // arguments. 2209 SourceRange Range; 2210 if (NumArgs > NumParams) 2211 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc); 2212 Diag(TemplateLoc, diag::err_template_arg_list_different_arity) 2213 << (NumArgs > NumParams) 2214 << (isa<ClassTemplateDecl>(Template)? 0 : 2215 isa<FunctionTemplateDecl>(Template)? 1 : 2216 isa<TemplateTemplateParmDecl>(Template)? 2 : 3) 2217 << Template << Range; 2218 Diag(Template->getLocation(), diag::note_template_decl_here) 2219 << Params->getSourceRange(); 2220 Invalid = true; 2221 } 2222 2223 // C++ [temp.arg]p1: 2224 // [...] The type and form of each template-argument specified in 2225 // a template-id shall match the type and form specified for the 2226 // corresponding parameter declared by the template in its 2227 // template-parameter-list. 2228 unsigned ArgIdx = 0; 2229 for (TemplateParameterList::iterator Param = Params->begin(), 2230 ParamEnd = Params->end(); 2231 Param != ParamEnd; ++Param, ++ArgIdx) { 2232 if (ArgIdx > NumArgs && PartialTemplateArgs) 2233 break; 2234 2235 // If we have a template parameter pack, check every remaining template 2236 // argument against that template parameter pack. 2237 if ((*Param)->isTemplateParameterPack()) { 2238 Converted.BeginPack(); 2239 for (; ArgIdx < NumArgs; ++ArgIdx) { 2240 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2241 TemplateLoc, RAngleLoc, Converted)) { 2242 Invalid = true; 2243 break; 2244 } 2245 } 2246 Converted.EndPack(); 2247 continue; 2248 } 2249 2250 if (ArgIdx < NumArgs) { 2251 // Check the template argument we were given. 2252 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2253 TemplateLoc, RAngleLoc, Converted)) 2254 return true; 2255 2256 continue; 2257 } 2258 2259 // We have a default template argument that we will use. 2260 TemplateArgumentLoc Arg; 2261 2262 // Retrieve the default template argument from the template 2263 // parameter. For each kind of template parameter, we substitute the 2264 // template arguments provided thus far and any "outer" template arguments 2265 // (when the template parameter was part of a nested template) into 2266 // the default argument. 2267 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { 2268 if (!TTP->hasDefaultArgument()) { 2269 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2270 break; 2271 } 2272 2273 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this, 2274 Template, 2275 TemplateLoc, 2276 RAngleLoc, 2277 TTP, 2278 Converted); 2279 if (!ArgType) 2280 return true; 2281 2282 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), 2283 ArgType); 2284 } else if (NonTypeTemplateParmDecl *NTTP 2285 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { 2286 if (!NTTP->hasDefaultArgument()) { 2287 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2288 break; 2289 } 2290 2291 ExprResult E = SubstDefaultTemplateArgument(*this, Template, 2292 TemplateLoc, 2293 RAngleLoc, 2294 NTTP, 2295 Converted); 2296 if (E.isInvalid()) 2297 return true; 2298 2299 Expr *Ex = E.takeAs<Expr>(); 2300 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); 2301 } else { 2302 TemplateTemplateParmDecl *TempParm 2303 = cast<TemplateTemplateParmDecl>(*Param); 2304 2305 if (!TempParm->hasDefaultArgument()) { 2306 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2307 break; 2308 } 2309 2310 TemplateName Name = SubstDefaultTemplateArgument(*this, Template, 2311 TemplateLoc, 2312 RAngleLoc, 2313 TempParm, 2314 Converted); 2315 if (Name.isNull()) 2316 return true; 2317 2318 Arg = TemplateArgumentLoc(TemplateArgument(Name), 2319 TempParm->getDefaultArgument().getTemplateQualifierRange(), 2320 TempParm->getDefaultArgument().getTemplateNameLoc()); 2321 } 2322 2323 // Introduce an instantiation record that describes where we are using 2324 // the default template argument. 2325 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, 2326 Converted.getFlatArguments(), 2327 Converted.flatSize(), 2328 SourceRange(TemplateLoc, RAngleLoc)); 2329 2330 // Check the default template argument. 2331 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, 2332 RAngleLoc, Converted)) 2333 return true; 2334 } 2335 2336 return Invalid; 2337} 2338 2339/// \brief Check a template argument against its corresponding 2340/// template type parameter. 2341/// 2342/// This routine implements the semantics of C++ [temp.arg.type]. It 2343/// returns true if an error occurred, and false otherwise. 2344bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, 2345 TypeSourceInfo *ArgInfo) { 2346 assert(ArgInfo && "invalid TypeSourceInfo"); 2347 QualType Arg = ArgInfo->getType(); 2348 2349 // C++ [temp.arg.type]p2: 2350 // A local type, a type with no linkage, an unnamed type or a type 2351 // compounded from any of these types shall not be used as a 2352 // template-argument for a template type-parameter. 2353 // 2354 // FIXME: Perform the unnamed type check. 2355 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); 2356 const TagType *Tag = 0; 2357 if (const EnumType *EnumT = Arg->getAs<EnumType>()) 2358 Tag = EnumT; 2359 else if (const RecordType *RecordT = Arg->getAs<RecordType>()) 2360 Tag = RecordT; 2361 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) { 2362 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); 2363 return Diag(SR.getBegin(), diag::err_template_arg_local_type) 2364 << QualType(Tag, 0) << SR; 2365 } else if (Tag && !Tag->getDecl()->getDeclName() && 2366 !Tag->getDecl()->getTypedefForAnonDecl()) { 2367 Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR; 2368 Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here); 2369 return true; 2370 } else if (Arg->isVariablyModifiedType()) { 2371 Diag(SR.getBegin(), diag::err_variably_modified_template_arg) 2372 << Arg; 2373 return true; 2374 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) { 2375 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR; 2376 } 2377 2378 return false; 2379} 2380 2381/// \brief Checks whether the given template argument is the address 2382/// of an object or function according to C++ [temp.arg.nontype]p1. 2383static bool 2384CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S, 2385 NonTypeTemplateParmDecl *Param, 2386 QualType ParamType, 2387 Expr *ArgIn, 2388 TemplateArgument &Converted) { 2389 bool Invalid = false; 2390 Expr *Arg = ArgIn; 2391 QualType ArgType = Arg->getType(); 2392 2393 // See through any implicit casts we added to fix the type. 2394 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2395 Arg = Cast->getSubExpr(); 2396 2397 // C++ [temp.arg.nontype]p1: 2398 // 2399 // A template-argument for a non-type, non-template 2400 // template-parameter shall be one of: [...] 2401 // 2402 // -- the address of an object or function with external 2403 // linkage, including function templates and function 2404 // template-ids but excluding non-static class members, 2405 // expressed as & id-expression where the & is optional if 2406 // the name refers to a function or array, or if the 2407 // corresponding template-parameter is a reference; or 2408 DeclRefExpr *DRE = 0; 2409 2410 // Ignore (and complain about) any excess parentheses. 2411 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2412 if (!Invalid) { 2413 S.Diag(Arg->getSourceRange().getBegin(), 2414 diag::err_template_arg_extra_parens) 2415 << Arg->getSourceRange(); 2416 Invalid = true; 2417 } 2418 2419 Arg = Parens->getSubExpr(); 2420 } 2421 2422 bool AddressTaken = false; 2423 SourceLocation AddrOpLoc; 2424 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2425 if (UnOp->getOpcode() == UO_AddrOf) { 2426 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2427 AddressTaken = true; 2428 AddrOpLoc = UnOp->getOperatorLoc(); 2429 } 2430 } else 2431 DRE = dyn_cast<DeclRefExpr>(Arg); 2432 2433 if (!DRE) { 2434 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref) 2435 << Arg->getSourceRange(); 2436 S.Diag(Param->getLocation(), diag::note_template_param_here); 2437 return true; 2438 } 2439 2440 // Stop checking the precise nature of the argument if it is value dependent, 2441 // it should be checked when instantiated. 2442 if (Arg->isValueDependent()) { 2443 Converted = TemplateArgument(ArgIn->Retain()); 2444 return false; 2445 } 2446 2447 if (!isa<ValueDecl>(DRE->getDecl())) { 2448 S.Diag(Arg->getSourceRange().getBegin(), 2449 diag::err_template_arg_not_object_or_func_form) 2450 << Arg->getSourceRange(); 2451 S.Diag(Param->getLocation(), diag::note_template_param_here); 2452 return true; 2453 } 2454 2455 NamedDecl *Entity = 0; 2456 2457 // Cannot refer to non-static data members 2458 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) { 2459 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field) 2460 << Field << Arg->getSourceRange(); 2461 S.Diag(Param->getLocation(), diag::note_template_param_here); 2462 return true; 2463 } 2464 2465 // Cannot refer to non-static member functions 2466 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl())) 2467 if (!Method->isStatic()) { 2468 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method) 2469 << Method << Arg->getSourceRange(); 2470 S.Diag(Param->getLocation(), diag::note_template_param_here); 2471 return true; 2472 } 2473 2474 // Functions must have external linkage. 2475 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) { 2476 if (!isExternalLinkage(Func->getLinkage())) { 2477 S.Diag(Arg->getSourceRange().getBegin(), 2478 diag::err_template_arg_function_not_extern) 2479 << Func << Arg->getSourceRange(); 2480 S.Diag(Func->getLocation(), diag::note_template_arg_internal_object) 2481 << true; 2482 return true; 2483 } 2484 2485 // Okay: we've named a function with external linkage. 2486 Entity = Func; 2487 2488 // If the template parameter has pointer type, the function decays. 2489 if (ParamType->isPointerType() && !AddressTaken) 2490 ArgType = S.Context.getPointerType(Func->getType()); 2491 else if (AddressTaken && ParamType->isReferenceType()) { 2492 // If we originally had an address-of operator, but the 2493 // parameter has reference type, complain and (if things look 2494 // like they will work) drop the address-of operator. 2495 if (!S.Context.hasSameUnqualifiedType(Func->getType(), 2496 ParamType.getNonReferenceType())) { 2497 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2498 << ParamType; 2499 S.Diag(Param->getLocation(), diag::note_template_param_here); 2500 return true; 2501 } 2502 2503 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2504 << ParamType 2505 << FixItHint::CreateRemoval(AddrOpLoc); 2506 S.Diag(Param->getLocation(), diag::note_template_param_here); 2507 2508 ArgType = Func->getType(); 2509 } 2510 } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 2511 if (!isExternalLinkage(Var->getLinkage())) { 2512 S.Diag(Arg->getSourceRange().getBegin(), 2513 diag::err_template_arg_object_not_extern) 2514 << Var << Arg->getSourceRange(); 2515 S.Diag(Var->getLocation(), diag::note_template_arg_internal_object) 2516 << true; 2517 return true; 2518 } 2519 2520 // A value of reference type is not an object. 2521 if (Var->getType()->isReferenceType()) { 2522 S.Diag(Arg->getSourceRange().getBegin(), 2523 diag::err_template_arg_reference_var) 2524 << Var->getType() << Arg->getSourceRange(); 2525 S.Diag(Param->getLocation(), diag::note_template_param_here); 2526 return true; 2527 } 2528 2529 // Okay: we've named an object with external linkage 2530 Entity = Var; 2531 2532 // If the template parameter has pointer type, we must have taken 2533 // the address of this object. 2534 if (ParamType->isReferenceType()) { 2535 if (AddressTaken) { 2536 // If we originally had an address-of operator, but the 2537 // parameter has reference type, complain and (if things look 2538 // like they will work) drop the address-of operator. 2539 if (!S.Context.hasSameUnqualifiedType(Var->getType(), 2540 ParamType.getNonReferenceType())) { 2541 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2542 << ParamType; 2543 S.Diag(Param->getLocation(), diag::note_template_param_here); 2544 return true; 2545 } 2546 2547 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2548 << ParamType 2549 << FixItHint::CreateRemoval(AddrOpLoc); 2550 S.Diag(Param->getLocation(), diag::note_template_param_here); 2551 2552 ArgType = Var->getType(); 2553 } 2554 } else if (!AddressTaken && ParamType->isPointerType()) { 2555 if (Var->getType()->isArrayType()) { 2556 // Array-to-pointer decay. 2557 ArgType = S.Context.getArrayDecayedType(Var->getType()); 2558 } else { 2559 // If the template parameter has pointer type but the address of 2560 // this object was not taken, complain and (possibly) recover by 2561 // taking the address of the entity. 2562 ArgType = S.Context.getPointerType(Var->getType()); 2563 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) { 2564 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2565 << ParamType; 2566 S.Diag(Param->getLocation(), diag::note_template_param_here); 2567 return true; 2568 } 2569 2570 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2571 << ParamType 2572 << FixItHint::CreateInsertion(Arg->getLocStart(), "&"); 2573 2574 S.Diag(Param->getLocation(), diag::note_template_param_here); 2575 } 2576 } 2577 } else { 2578 // We found something else, but we don't know specifically what it is. 2579 S.Diag(Arg->getSourceRange().getBegin(), 2580 diag::err_template_arg_not_object_or_func) 2581 << Arg->getSourceRange(); 2582 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); 2583 return true; 2584 } 2585 2586 if (ParamType->isPointerType() && 2587 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() && 2588 S.IsQualificationConversion(ArgType, ParamType)) { 2589 // For pointer-to-object types, qualification conversions are 2590 // permitted. 2591 } else { 2592 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) { 2593 if (!ParamRef->getPointeeType()->isFunctionType()) { 2594 // C++ [temp.arg.nontype]p5b3: 2595 // For a non-type template-parameter of type reference to 2596 // object, no conversions apply. The type referred to by the 2597 // reference may be more cv-qualified than the (otherwise 2598 // identical) type of the template- argument. The 2599 // template-parameter is bound directly to the 2600 // template-argument, which shall be an lvalue. 2601 2602 // FIXME: Other qualifiers? 2603 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers(); 2604 unsigned ArgQuals = ArgType.getCVRQualifiers(); 2605 2606 if ((ParamQuals | ArgQuals) != ParamQuals) { 2607 S.Diag(Arg->getSourceRange().getBegin(), 2608 diag::err_template_arg_ref_bind_ignores_quals) 2609 << ParamType << Arg->getType() 2610 << Arg->getSourceRange(); 2611 S.Diag(Param->getLocation(), diag::note_template_param_here); 2612 return true; 2613 } 2614 } 2615 } 2616 2617 // At this point, the template argument refers to an object or 2618 // function with external linkage. We now need to check whether the 2619 // argument and parameter types are compatible. 2620 if (!S.Context.hasSameUnqualifiedType(ArgType, 2621 ParamType.getNonReferenceType())) { 2622 // We can't perform this conversion or binding. 2623 if (ParamType->isReferenceType()) 2624 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind) 2625 << ParamType << Arg->getType() << Arg->getSourceRange(); 2626 else 2627 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible) 2628 << Arg->getType() << ParamType << Arg->getSourceRange(); 2629 S.Diag(Param->getLocation(), diag::note_template_param_here); 2630 return true; 2631 } 2632 } 2633 2634 // Create the template argument. 2635 Converted = TemplateArgument(Entity->getCanonicalDecl()); 2636 S.MarkDeclarationReferenced(Arg->getLocStart(), Entity); 2637 return false; 2638} 2639 2640/// \brief Checks whether the given template argument is a pointer to 2641/// member constant according to C++ [temp.arg.nontype]p1. 2642bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, 2643 TemplateArgument &Converted) { 2644 bool Invalid = false; 2645 2646 // See through any implicit casts we added to fix the type. 2647 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2648 Arg = Cast->getSubExpr(); 2649 2650 // C++ [temp.arg.nontype]p1: 2651 // 2652 // A template-argument for a non-type, non-template 2653 // template-parameter shall be one of: [...] 2654 // 2655 // -- a pointer to member expressed as described in 5.3.1. 2656 DeclRefExpr *DRE = 0; 2657 2658 // Ignore (and complain about) any excess parentheses. 2659 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2660 if (!Invalid) { 2661 Diag(Arg->getSourceRange().getBegin(), 2662 diag::err_template_arg_extra_parens) 2663 << Arg->getSourceRange(); 2664 Invalid = true; 2665 } 2666 2667 Arg = Parens->getSubExpr(); 2668 } 2669 2670 // A pointer-to-member constant written &Class::member. 2671 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2672 if (UnOp->getOpcode() == UO_AddrOf) { 2673 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2674 if (DRE && !DRE->getQualifier()) 2675 DRE = 0; 2676 } 2677 } 2678 // A constant of pointer-to-member type. 2679 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { 2680 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { 2681 if (VD->getType()->isMemberPointerType()) { 2682 if (isa<NonTypeTemplateParmDecl>(VD) || 2683 (isa<VarDecl>(VD) && 2684 Context.getCanonicalType(VD->getType()).isConstQualified())) { 2685 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2686 Converted = TemplateArgument(Arg->Retain()); 2687 else 2688 Converted = TemplateArgument(VD->getCanonicalDecl()); 2689 return Invalid; 2690 } 2691 } 2692 } 2693 2694 DRE = 0; 2695 } 2696 2697 if (!DRE) 2698 return Diag(Arg->getSourceRange().getBegin(), 2699 diag::err_template_arg_not_pointer_to_member_form) 2700 << Arg->getSourceRange(); 2701 2702 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { 2703 assert((isa<FieldDecl>(DRE->getDecl()) || 2704 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && 2705 "Only non-static member pointers can make it here"); 2706 2707 // Okay: this is the address of a non-static member, and therefore 2708 // a member pointer constant. 2709 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2710 Converted = TemplateArgument(Arg->Retain()); 2711 else 2712 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); 2713 return Invalid; 2714 } 2715 2716 // We found something else, but we don't know specifically what it is. 2717 Diag(Arg->getSourceRange().getBegin(), 2718 diag::err_template_arg_not_pointer_to_member_form) 2719 << Arg->getSourceRange(); 2720 Diag(DRE->getDecl()->getLocation(), 2721 diag::note_template_arg_refers_here); 2722 return true; 2723} 2724 2725/// \brief Check a template argument against its corresponding 2726/// non-type template parameter. 2727/// 2728/// This routine implements the semantics of C++ [temp.arg.nontype]. 2729/// It returns true if an error occurred, and false otherwise. \p 2730/// InstantiatedParamType is the type of the non-type template 2731/// parameter after it has been instantiated. 2732/// 2733/// If no error was detected, Converted receives the converted template argument. 2734bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, 2735 QualType InstantiatedParamType, Expr *&Arg, 2736 TemplateArgument &Converted, 2737 CheckTemplateArgumentKind CTAK) { 2738 SourceLocation StartLoc = Arg->getSourceRange().getBegin(); 2739 2740 // If either the parameter has a dependent type or the argument is 2741 // type-dependent, there's nothing we can check now. 2742 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { 2743 // FIXME: Produce a cloned, canonical expression? 2744 Converted = TemplateArgument(Arg); 2745 return false; 2746 } 2747 2748 // C++ [temp.arg.nontype]p5: 2749 // The following conversions are performed on each expression used 2750 // as a non-type template-argument. If a non-type 2751 // template-argument cannot be converted to the type of the 2752 // corresponding template-parameter then the program is 2753 // ill-formed. 2754 // 2755 // -- for a non-type template-parameter of integral or 2756 // enumeration type, integral promotions (4.5) and integral 2757 // conversions (4.7) are applied. 2758 QualType ParamType = InstantiatedParamType; 2759 QualType ArgType = Arg->getType(); 2760 if (ParamType->isIntegralOrEnumerationType()) { 2761 // C++ [temp.arg.nontype]p1: 2762 // A template-argument for a non-type, non-template 2763 // template-parameter shall be one of: 2764 // 2765 // -- an integral constant-expression of integral or enumeration 2766 // type; or 2767 // -- the name of a non-type template-parameter; or 2768 SourceLocation NonConstantLoc; 2769 llvm::APSInt Value; 2770 if (!ArgType->isIntegralOrEnumerationType()) { 2771 Diag(Arg->getSourceRange().getBegin(), 2772 diag::err_template_arg_not_integral_or_enumeral) 2773 << ArgType << Arg->getSourceRange(); 2774 Diag(Param->getLocation(), diag::note_template_param_here); 2775 return true; 2776 } else if (!Arg->isValueDependent() && 2777 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) { 2778 Diag(NonConstantLoc, diag::err_template_arg_not_ice) 2779 << ArgType << Arg->getSourceRange(); 2780 return true; 2781 } 2782 2783 // From here on out, all we care about are the unqualified forms 2784 // of the parameter and argument types. 2785 ParamType = ParamType.getUnqualifiedType(); 2786 ArgType = ArgType.getUnqualifiedType(); 2787 2788 // Try to convert the argument to the parameter's type. 2789 if (Context.hasSameType(ParamType, ArgType)) { 2790 // Okay: no conversion necessary 2791 } else if (CTAK == CTAK_Deduced) { 2792 // C++ [temp.deduct.type]p17: 2793 // If, in the declaration of a function template with a non-type 2794 // template-parameter, the non-type template- parameter is used 2795 // in an expression in the function parameter-list and, if the 2796 // corresponding template-argument is deduced, the 2797 // template-argument type shall match the type of the 2798 // template-parameter exactly, except that a template-argument 2799 // deduced from an array bound may be of any integral type. 2800 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch) 2801 << ArgType << ParamType; 2802 Diag(Param->getLocation(), diag::note_template_param_here); 2803 return true; 2804 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || 2805 !ParamType->isEnumeralType()) { 2806 // This is an integral promotion or conversion. 2807 ImpCastExprToType(Arg, ParamType, CK_IntegralCast); 2808 } else { 2809 // We can't perform this conversion. 2810 Diag(Arg->getSourceRange().getBegin(), 2811 diag::err_template_arg_not_convertible) 2812 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2813 Diag(Param->getLocation(), diag::note_template_param_here); 2814 return true; 2815 } 2816 2817 QualType IntegerType = Context.getCanonicalType(ParamType); 2818 if (const EnumType *Enum = IntegerType->getAs<EnumType>()) 2819 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); 2820 2821 if (!Arg->isValueDependent()) { 2822 llvm::APSInt OldValue = Value; 2823 2824 // Coerce the template argument's value to the value it will have 2825 // based on the template parameter's type. 2826 unsigned AllowedBits = Context.getTypeSize(IntegerType); 2827 if (Value.getBitWidth() != AllowedBits) 2828 Value.extOrTrunc(AllowedBits); 2829 Value.setIsSigned(IntegerType->isSignedIntegerType()); 2830 2831 // Complain if an unsigned parameter received a negative value. 2832 if (IntegerType->isUnsignedIntegerType() 2833 && (OldValue.isSigned() && OldValue.isNegative())) { 2834 Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative) 2835 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2836 << Arg->getSourceRange(); 2837 Diag(Param->getLocation(), diag::note_template_param_here); 2838 } 2839 2840 // Complain if we overflowed the template parameter's type. 2841 unsigned RequiredBits; 2842 if (IntegerType->isUnsignedIntegerType()) 2843 RequiredBits = OldValue.getActiveBits(); 2844 else if (OldValue.isUnsigned()) 2845 RequiredBits = OldValue.getActiveBits() + 1; 2846 else 2847 RequiredBits = OldValue.getMinSignedBits(); 2848 if (RequiredBits > AllowedBits) { 2849 Diag(Arg->getSourceRange().getBegin(), 2850 diag::warn_template_arg_too_large) 2851 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2852 << Arg->getSourceRange(); 2853 Diag(Param->getLocation(), diag::note_template_param_here); 2854 } 2855 } 2856 2857 // Add the value of this argument to the list of converted 2858 // arguments. We use the bitwidth and signedness of the template 2859 // parameter. 2860 if (Arg->isValueDependent()) { 2861 // The argument is value-dependent. Create a new 2862 // TemplateArgument with the converted expression. 2863 Converted = TemplateArgument(Arg); 2864 return false; 2865 } 2866 2867 Converted = TemplateArgument(Value, 2868 ParamType->isEnumeralType() ? ParamType 2869 : IntegerType); 2870 return false; 2871 } 2872 2873 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction 2874 2875 // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion 2876 // from a template argument of type std::nullptr_t to a non-type 2877 // template parameter of type pointer to object, pointer to 2878 // function, or pointer-to-member, respectively. 2879 if (ArgType->isNullPtrType() && 2880 (ParamType->isPointerType() || ParamType->isMemberPointerType())) { 2881 Converted = TemplateArgument((NamedDecl *)0); 2882 return false; 2883 } 2884 2885 // Handle pointer-to-function, reference-to-function, and 2886 // pointer-to-member-function all in (roughly) the same way. 2887 if (// -- For a non-type template-parameter of type pointer to 2888 // function, only the function-to-pointer conversion (4.3) is 2889 // applied. If the template-argument represents a set of 2890 // overloaded functions (or a pointer to such), the matching 2891 // function is selected from the set (13.4). 2892 (ParamType->isPointerType() && 2893 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || 2894 // -- For a non-type template-parameter of type reference to 2895 // function, no conversions apply. If the template-argument 2896 // represents a set of overloaded functions, the matching 2897 // function is selected from the set (13.4). 2898 (ParamType->isReferenceType() && 2899 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || 2900 // -- For a non-type template-parameter of type pointer to 2901 // member function, no conversions apply. If the 2902 // template-argument represents a set of overloaded member 2903 // functions, the matching member function is selected from 2904 // the set (13.4). 2905 (ParamType->isMemberPointerType() && 2906 ParamType->getAs<MemberPointerType>()->getPointeeType() 2907 ->isFunctionType())) { 2908 2909 if (Arg->getType() == Context.OverloadTy) { 2910 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType, 2911 true, 2912 FoundResult)) { 2913 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2914 return true; 2915 2916 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2917 ArgType = Arg->getType(); 2918 } else 2919 return true; 2920 } 2921 2922 if (!ParamType->isMemberPointerType()) 2923 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2924 ParamType, 2925 Arg, Converted); 2926 2927 if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType())) { 2928 ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg)); 2929 } else if (!Context.hasSameUnqualifiedType(ArgType, 2930 ParamType.getNonReferenceType())) { 2931 // We can't perform this conversion. 2932 Diag(Arg->getSourceRange().getBegin(), 2933 diag::err_template_arg_not_convertible) 2934 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2935 Diag(Param->getLocation(), diag::note_template_param_here); 2936 return true; 2937 } 2938 2939 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2940 } 2941 2942 if (ParamType->isPointerType()) { 2943 // -- for a non-type template-parameter of type pointer to 2944 // object, qualification conversions (4.4) and the 2945 // array-to-pointer conversion (4.2) are applied. 2946 // C++0x also allows a value of std::nullptr_t. 2947 assert(ParamType->getPointeeType()->isIncompleteOrObjectType() && 2948 "Only object pointers allowed here"); 2949 2950 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2951 ParamType, 2952 Arg, Converted); 2953 } 2954 2955 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { 2956 // -- For a non-type template-parameter of type reference to 2957 // object, no conversions apply. The type referred to by the 2958 // reference may be more cv-qualified than the (otherwise 2959 // identical) type of the template-argument. The 2960 // template-parameter is bound directly to the 2961 // template-argument, which must be an lvalue. 2962 assert(ParamRefType->getPointeeType()->isIncompleteOrObjectType() && 2963 "Only object references allowed here"); 2964 2965 if (Arg->getType() == Context.OverloadTy) { 2966 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, 2967 ParamRefType->getPointeeType(), 2968 true, 2969 FoundResult)) { 2970 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2971 return true; 2972 2973 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2974 ArgType = Arg->getType(); 2975 } else 2976 return true; 2977 } 2978 2979 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2980 ParamType, 2981 Arg, Converted); 2982 } 2983 2984 // -- For a non-type template-parameter of type pointer to data 2985 // member, qualification conversions (4.4) are applied. 2986 assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); 2987 2988 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) { 2989 // Types match exactly: nothing more to do here. 2990 } else if (IsQualificationConversion(ArgType, ParamType)) { 2991 ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg)); 2992 } else { 2993 // We can't perform this conversion. 2994 Diag(Arg->getSourceRange().getBegin(), 2995 diag::err_template_arg_not_convertible) 2996 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2997 Diag(Param->getLocation(), diag::note_template_param_here); 2998 return true; 2999 } 3000 3001 return CheckTemplateArgumentPointerToMember(Arg, Converted); 3002} 3003 3004/// \brief Check a template argument against its corresponding 3005/// template template parameter. 3006/// 3007/// This routine implements the semantics of C++ [temp.arg.template]. 3008/// It returns true if an error occurred, and false otherwise. 3009bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, 3010 const TemplateArgumentLoc &Arg) { 3011 TemplateName Name = Arg.getArgument().getAsTemplate(); 3012 TemplateDecl *Template = Name.getAsTemplateDecl(); 3013 if (!Template) { 3014 // Any dependent template name is fine. 3015 assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); 3016 return false; 3017 } 3018 3019 // C++ [temp.arg.template]p1: 3020 // A template-argument for a template template-parameter shall be 3021 // the name of a class template, expressed as id-expression. Only 3022 // primary class templates are considered when matching the 3023 // template template argument with the corresponding parameter; 3024 // partial specializations are not considered even if their 3025 // parameter lists match that of the template template parameter. 3026 // 3027 // Note that we also allow template template parameters here, which 3028 // will happen when we are dealing with, e.g., class template 3029 // partial specializations. 3030 if (!isa<ClassTemplateDecl>(Template) && 3031 !isa<TemplateTemplateParmDecl>(Template)) { 3032 assert(isa<FunctionTemplateDecl>(Template) && 3033 "Only function templates are possible here"); 3034 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); 3035 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) 3036 << Template; 3037 } 3038 3039 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), 3040 Param->getTemplateParameters(), 3041 true, 3042 TPL_TemplateTemplateArgumentMatch, 3043 Arg.getLocation()); 3044} 3045 3046/// \brief Given a non-type template argument that refers to a 3047/// declaration and the type of its corresponding non-type template 3048/// parameter, produce an expression that properly refers to that 3049/// declaration. 3050ExprResult 3051Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg, 3052 QualType ParamType, 3053 SourceLocation Loc) { 3054 assert(Arg.getKind() == TemplateArgument::Declaration && 3055 "Only declaration template arguments permitted here"); 3056 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl()); 3057 3058 if (VD->getDeclContext()->isRecord() && 3059 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) { 3060 // If the value is a class member, we might have a pointer-to-member. 3061 // Determine whether the non-type template template parameter is of 3062 // pointer-to-member type. If so, we need to build an appropriate 3063 // expression for a pointer-to-member, since a "normal" DeclRefExpr 3064 // would refer to the member itself. 3065 if (ParamType->isMemberPointerType()) { 3066 QualType ClassType 3067 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext())); 3068 NestedNameSpecifier *Qualifier 3069 = NestedNameSpecifier::Create(Context, 0, false, 3070 ClassType.getTypePtr()); 3071 CXXScopeSpec SS; 3072 SS.setScopeRep(Qualifier); 3073 ExprResult RefExpr = BuildDeclRefExpr(VD, 3074 VD->getType().getNonReferenceType(), 3075 Loc, 3076 &SS); 3077 if (RefExpr.isInvalid()) 3078 return ExprError(); 3079 3080 RefExpr = CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get()); 3081 3082 // We might need to perform a trailing qualification conversion, since 3083 // the element type on the parameter could be more qualified than the 3084 // element type in the expression we constructed. 3085 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(), 3086 ParamType.getUnqualifiedType())) { 3087 Expr *RefE = RefExpr.takeAs<Expr>(); 3088 ImpCastExprToType(RefE, ParamType.getUnqualifiedType(), CK_NoOp); 3089 RefExpr = Owned(RefE); 3090 } 3091 3092 assert(!RefExpr.isInvalid() && 3093 Context.hasSameType(((Expr*) RefExpr.get())->getType(), 3094 ParamType.getUnqualifiedType())); 3095 return move(RefExpr); 3096 } 3097 } 3098 3099 QualType T = VD->getType().getNonReferenceType(); 3100 if (ParamType->isPointerType()) { 3101 // When the non-type template parameter is a pointer, take the 3102 // address of the declaration. 3103 ExprResult RefExpr = BuildDeclRefExpr(VD, T, Loc); 3104 if (RefExpr.isInvalid()) 3105 return ExprError(); 3106 3107 if (T->isFunctionType() || T->isArrayType()) { 3108 // Decay functions and arrays. 3109 Expr *RefE = (Expr *)RefExpr.get(); 3110 DefaultFunctionArrayConversion(RefE); 3111 if (RefE != RefExpr.get()) { 3112 RefExpr.release(); 3113 RefExpr = Owned(RefE); 3114 } 3115 3116 return move(RefExpr); 3117 } 3118 3119 // Take the address of everything else 3120 return CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get()); 3121 } 3122 3123 // If the non-type template parameter has reference type, qualify the 3124 // resulting declaration reference with the extra qualifiers on the 3125 // type that the reference refers to. 3126 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) 3127 T = Context.getQualifiedType(T, TargetRef->getPointeeType().getQualifiers()); 3128 3129 return BuildDeclRefExpr(VD, T, Loc); 3130} 3131 3132/// \brief Construct a new expression that refers to the given 3133/// integral template argument with the given source-location 3134/// information. 3135/// 3136/// This routine takes care of the mapping from an integral template 3137/// argument (which may have any integral type) to the appropriate 3138/// literal value. 3139ExprResult 3140Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg, 3141 SourceLocation Loc) { 3142 assert(Arg.getKind() == TemplateArgument::Integral && 3143 "Operation is only value for integral template arguments"); 3144 QualType T = Arg.getIntegralType(); 3145 if (T->isCharType() || T->isWideCharType()) 3146 return Owned(new (Context) CharacterLiteral( 3147 Arg.getAsIntegral()->getZExtValue(), 3148 T->isWideCharType(), 3149 T, 3150 Loc)); 3151 if (T->isBooleanType()) 3152 return Owned(new (Context) CXXBoolLiteralExpr( 3153 Arg.getAsIntegral()->getBoolValue(), 3154 T, 3155 Loc)); 3156 3157 return Owned(IntegerLiteral::Create(Context, *Arg.getAsIntegral(), T, Loc)); 3158} 3159 3160 3161/// \brief Determine whether the given template parameter lists are 3162/// equivalent. 3163/// 3164/// \param New The new template parameter list, typically written in the 3165/// source code as part of a new template declaration. 3166/// 3167/// \param Old The old template parameter list, typically found via 3168/// name lookup of the template declared with this template parameter 3169/// list. 3170/// 3171/// \param Complain If true, this routine will produce a diagnostic if 3172/// the template parameter lists are not equivalent. 3173/// 3174/// \param Kind describes how we are to match the template parameter lists. 3175/// 3176/// \param TemplateArgLoc If this source location is valid, then we 3177/// are actually checking the template parameter list of a template 3178/// argument (New) against the template parameter list of its 3179/// corresponding template template parameter (Old). We produce 3180/// slightly different diagnostics in this scenario. 3181/// 3182/// \returns True if the template parameter lists are equal, false 3183/// otherwise. 3184bool 3185Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, 3186 TemplateParameterList *Old, 3187 bool Complain, 3188 TemplateParameterListEqualKind Kind, 3189 SourceLocation TemplateArgLoc) { 3190 if (Old->size() != New->size()) { 3191 if (Complain) { 3192 unsigned NextDiag = diag::err_template_param_list_different_arity; 3193 if (TemplateArgLoc.isValid()) { 3194 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3195 NextDiag = diag::note_template_param_list_different_arity; 3196 } 3197 Diag(New->getTemplateLoc(), NextDiag) 3198 << (New->size() > Old->size()) 3199 << (Kind != TPL_TemplateMatch) 3200 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); 3201 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) 3202 << (Kind != TPL_TemplateMatch) 3203 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); 3204 } 3205 3206 return false; 3207 } 3208 3209 for (TemplateParameterList::iterator OldParm = Old->begin(), 3210 OldParmEnd = Old->end(), NewParm = New->begin(); 3211 OldParm != OldParmEnd; ++OldParm, ++NewParm) { 3212 if ((*OldParm)->getKind() != (*NewParm)->getKind()) { 3213 if (Complain) { 3214 unsigned NextDiag = diag::err_template_param_different_kind; 3215 if (TemplateArgLoc.isValid()) { 3216 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3217 NextDiag = diag::note_template_param_different_kind; 3218 } 3219 Diag((*NewParm)->getLocation(), NextDiag) 3220 << (Kind != TPL_TemplateMatch); 3221 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration) 3222 << (Kind != TPL_TemplateMatch); 3223 } 3224 return false; 3225 } 3226 3227 if (TemplateTypeParmDecl *OldTTP 3228 = dyn_cast<TemplateTypeParmDecl>(*OldParm)) { 3229 // Template type parameters are equivalent if either both are template 3230 // type parameter packs or neither are (since we know we're at the same 3231 // index). 3232 TemplateTypeParmDecl *NewTTP = cast<TemplateTypeParmDecl>(*NewParm); 3233 if (OldTTP->isParameterPack() != NewTTP->isParameterPack()) { 3234 // FIXME: Implement the rules in C++0x [temp.arg.template]p5 that 3235 // allow one to match a template parameter pack in the template 3236 // parameter list of a template template parameter to one or more 3237 // template parameters in the template parameter list of the 3238 // corresponding template template argument. 3239 if (Complain) { 3240 unsigned NextDiag = diag::err_template_parameter_pack_non_pack; 3241 if (TemplateArgLoc.isValid()) { 3242 Diag(TemplateArgLoc, 3243 diag::err_template_arg_template_params_mismatch); 3244 NextDiag = diag::note_template_parameter_pack_non_pack; 3245 } 3246 Diag(NewTTP->getLocation(), NextDiag) 3247 << 0 << NewTTP->isParameterPack(); 3248 Diag(OldTTP->getLocation(), diag::note_template_parameter_pack_here) 3249 << 0 << OldTTP->isParameterPack(); 3250 } 3251 return false; 3252 } 3253 } else if (NonTypeTemplateParmDecl *OldNTTP 3254 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) { 3255 // The types of non-type template parameters must agree. 3256 NonTypeTemplateParmDecl *NewNTTP 3257 = cast<NonTypeTemplateParmDecl>(*NewParm); 3258 3259 // If we are matching a template template argument to a template 3260 // template parameter and one of the non-type template parameter types 3261 // is dependent, then we must wait until template instantiation time 3262 // to actually compare the arguments. 3263 if (Kind == TPL_TemplateTemplateArgumentMatch && 3264 (OldNTTP->getType()->isDependentType() || 3265 NewNTTP->getType()->isDependentType())) 3266 continue; 3267 3268 if (Context.getCanonicalType(OldNTTP->getType()) != 3269 Context.getCanonicalType(NewNTTP->getType())) { 3270 if (Complain) { 3271 unsigned NextDiag = diag::err_template_nontype_parm_different_type; 3272 if (TemplateArgLoc.isValid()) { 3273 Diag(TemplateArgLoc, 3274 diag::err_template_arg_template_params_mismatch); 3275 NextDiag = diag::note_template_nontype_parm_different_type; 3276 } 3277 Diag(NewNTTP->getLocation(), NextDiag) 3278 << NewNTTP->getType() 3279 << (Kind != TPL_TemplateMatch); 3280 Diag(OldNTTP->getLocation(), 3281 diag::note_template_nontype_parm_prev_declaration) 3282 << OldNTTP->getType(); 3283 } 3284 return false; 3285 } 3286 } else { 3287 // The template parameter lists of template template 3288 // parameters must agree. 3289 assert(isa<TemplateTemplateParmDecl>(*OldParm) && 3290 "Only template template parameters handled here"); 3291 TemplateTemplateParmDecl *OldTTP 3292 = cast<TemplateTemplateParmDecl>(*OldParm); 3293 TemplateTemplateParmDecl *NewTTP 3294 = cast<TemplateTemplateParmDecl>(*NewParm); 3295 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), 3296 OldTTP->getTemplateParameters(), 3297 Complain, 3298 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind), 3299 TemplateArgLoc)) 3300 return false; 3301 } 3302 } 3303 3304 return true; 3305} 3306 3307/// \brief Check whether a template can be declared within this scope. 3308/// 3309/// If the template declaration is valid in this scope, returns 3310/// false. Otherwise, issues a diagnostic and returns true. 3311bool 3312Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { 3313 // Find the nearest enclosing declaration scope. 3314 while ((S->getFlags() & Scope::DeclScope) == 0 || 3315 (S->getFlags() & Scope::TemplateParamScope) != 0) 3316 S = S->getParent(); 3317 3318 // C++ [temp]p2: 3319 // A template-declaration can appear only as a namespace scope or 3320 // class scope declaration. 3321 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 3322 if (Ctx && isa<LinkageSpecDecl>(Ctx) && 3323 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) 3324 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) 3325 << TemplateParams->getSourceRange(); 3326 3327 while (Ctx && isa<LinkageSpecDecl>(Ctx)) 3328 Ctx = Ctx->getParent(); 3329 3330 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) 3331 return false; 3332 3333 return Diag(TemplateParams->getTemplateLoc(), 3334 diag::err_template_outside_namespace_or_class_scope) 3335 << TemplateParams->getSourceRange(); 3336} 3337 3338/// \brief Determine what kind of template specialization the given declaration 3339/// is. 3340static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) { 3341 if (!D) 3342 return TSK_Undeclared; 3343 3344 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) 3345 return Record->getTemplateSpecializationKind(); 3346 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) 3347 return Function->getTemplateSpecializationKind(); 3348 if (VarDecl *Var = dyn_cast<VarDecl>(D)) 3349 return Var->getTemplateSpecializationKind(); 3350 3351 return TSK_Undeclared; 3352} 3353 3354/// \brief Check whether a specialization is well-formed in the current 3355/// context. 3356/// 3357/// This routine determines whether a template specialization can be declared 3358/// in the current context (C++ [temp.expl.spec]p2). 3359/// 3360/// \param S the semantic analysis object for which this check is being 3361/// performed. 3362/// 3363/// \param Specialized the entity being specialized or instantiated, which 3364/// may be a kind of template (class template, function template, etc.) or 3365/// a member of a class template (member function, static data member, 3366/// member class). 3367/// 3368/// \param PrevDecl the previous declaration of this entity, if any. 3369/// 3370/// \param Loc the location of the explicit specialization or instantiation of 3371/// this entity. 3372/// 3373/// \param IsPartialSpecialization whether this is a partial specialization of 3374/// a class template. 3375/// 3376/// \returns true if there was an error that we cannot recover from, false 3377/// otherwise. 3378static bool CheckTemplateSpecializationScope(Sema &S, 3379 NamedDecl *Specialized, 3380 NamedDecl *PrevDecl, 3381 SourceLocation Loc, 3382 bool IsPartialSpecialization) { 3383 // Keep these "kind" numbers in sync with the %select statements in the 3384 // various diagnostics emitted by this routine. 3385 int EntityKind = 0; 3386 bool isTemplateSpecialization = false; 3387 if (isa<ClassTemplateDecl>(Specialized)) { 3388 EntityKind = IsPartialSpecialization? 1 : 0; 3389 isTemplateSpecialization = true; 3390 } else if (isa<FunctionTemplateDecl>(Specialized)) { 3391 EntityKind = 2; 3392 isTemplateSpecialization = true; 3393 } else if (isa<CXXMethodDecl>(Specialized)) 3394 EntityKind = 3; 3395 else if (isa<VarDecl>(Specialized)) 3396 EntityKind = 4; 3397 else if (isa<RecordDecl>(Specialized)) 3398 EntityKind = 5; 3399 else { 3400 S.Diag(Loc, diag::err_template_spec_unknown_kind); 3401 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3402 return true; 3403 } 3404 3405 // C++ [temp.expl.spec]p2: 3406 // An explicit specialization shall be declared in the namespace 3407 // of which the template is a member, or, for member templates, in 3408 // the namespace of which the enclosing class or enclosing class 3409 // template is a member. An explicit specialization of a member 3410 // function, member class or static data member of a class 3411 // template shall be declared in the namespace of which the class 3412 // template is a member. Such a declaration may also be a 3413 // definition. If the declaration is not a definition, the 3414 // specialization may be defined later in the name- space in which 3415 // the explicit specialization was declared, or in a namespace 3416 // that encloses the one in which the explicit specialization was 3417 // declared. 3418 if (S.CurContext->getRedeclContext()->isFunctionOrMethod()) { 3419 S.Diag(Loc, diag::err_template_spec_decl_function_scope) 3420 << Specialized; 3421 return true; 3422 } 3423 3424 if (S.CurContext->isRecord() && !IsPartialSpecialization) { 3425 S.Diag(Loc, diag::err_template_spec_decl_class_scope) 3426 << Specialized; 3427 return true; 3428 } 3429 3430 // C++ [temp.class.spec]p6: 3431 // A class template partial specialization may be declared or redeclared 3432 // in any namespace scope in which its definition may be defined (14.5.1 3433 // and 14.5.2). 3434 bool ComplainedAboutScope = false; 3435 DeclContext *SpecializedContext 3436 = Specialized->getDeclContext()->getEnclosingNamespaceContext(); 3437 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); 3438 if ((!PrevDecl || 3439 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || 3440 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ 3441 // There is no prior declaration of this entity, so this 3442 // specialization must be in the same context as the template 3443 // itself. 3444 if (!DC->Equals(SpecializedContext)) { 3445 if (isa<TranslationUnitDecl>(SpecializedContext)) 3446 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) 3447 << EntityKind << Specialized; 3448 else if (isa<NamespaceDecl>(SpecializedContext)) 3449 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope) 3450 << EntityKind << Specialized 3451 << cast<NamedDecl>(SpecializedContext); 3452 3453 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3454 ComplainedAboutScope = true; 3455 } 3456 } 3457 3458 // Make sure that this redeclaration (or definition) occurs in an enclosing 3459 // namespace. 3460 // Note that HandleDeclarator() performs this check for explicit 3461 // specializations of function templates, static data members, and member 3462 // functions, so we skip the check here for those kinds of entities. 3463 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. 3464 // Should we refactor that check, so that it occurs later? 3465 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && 3466 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || 3467 isa<FunctionDecl>(Specialized))) { 3468 if (isa<TranslationUnitDecl>(SpecializedContext)) 3469 S.Diag(Loc, diag::err_template_spec_redecl_global_scope) 3470 << EntityKind << Specialized; 3471 else if (isa<NamespaceDecl>(SpecializedContext)) 3472 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) 3473 << EntityKind << Specialized 3474 << cast<NamedDecl>(SpecializedContext); 3475 3476 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3477 } 3478 3479 // FIXME: check for specialization-after-instantiation errors and such. 3480 3481 return false; 3482} 3483 3484/// \brief Check the non-type template arguments of a class template 3485/// partial specialization according to C++ [temp.class.spec]p9. 3486/// 3487/// \param TemplateParams the template parameters of the primary class 3488/// template. 3489/// 3490/// \param TemplateArg the template arguments of the class template 3491/// partial specialization. 3492/// 3493/// \param MirrorsPrimaryTemplate will be set true if the class 3494/// template partial specialization arguments are identical to the 3495/// implicit template arguments of the primary template. This is not 3496/// necessarily an error (C++0x), and it is left to the caller to diagnose 3497/// this condition when it is an error. 3498/// 3499/// \returns true if there was an error, false otherwise. 3500bool Sema::CheckClassTemplatePartialSpecializationArgs( 3501 TemplateParameterList *TemplateParams, 3502 const TemplateArgumentListBuilder &TemplateArgs, 3503 bool &MirrorsPrimaryTemplate) { 3504 // FIXME: the interface to this function will have to change to 3505 // accommodate variadic templates. 3506 MirrorsPrimaryTemplate = true; 3507 3508 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments(); 3509 3510 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3511 // Determine whether the template argument list of the partial 3512 // specialization is identical to the implicit argument list of 3513 // the primary template. The caller may need to diagnostic this as 3514 // an error per C++ [temp.class.spec]p9b3. 3515 if (MirrorsPrimaryTemplate) { 3516 if (TemplateTypeParmDecl *TTP 3517 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) { 3518 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) != 3519 Context.getCanonicalType(ArgList[I].getAsType())) 3520 MirrorsPrimaryTemplate = false; 3521 } else if (TemplateTemplateParmDecl *TTP 3522 = dyn_cast<TemplateTemplateParmDecl>( 3523 TemplateParams->getParam(I))) { 3524 TemplateName Name = ArgList[I].getAsTemplate(); 3525 TemplateTemplateParmDecl *ArgDecl 3526 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()); 3527 if (!ArgDecl || 3528 ArgDecl->getIndex() != TTP->getIndex() || 3529 ArgDecl->getDepth() != TTP->getDepth()) 3530 MirrorsPrimaryTemplate = false; 3531 } 3532 } 3533 3534 NonTypeTemplateParmDecl *Param 3535 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); 3536 if (!Param) { 3537 continue; 3538 } 3539 3540 Expr *ArgExpr = ArgList[I].getAsExpr(); 3541 if (!ArgExpr) { 3542 MirrorsPrimaryTemplate = false; 3543 continue; 3544 } 3545 3546 // C++ [temp.class.spec]p8: 3547 // A non-type argument is non-specialized if it is the name of a 3548 // non-type parameter. All other non-type arguments are 3549 // specialized. 3550 // 3551 // Below, we check the two conditions that only apply to 3552 // specialized non-type arguments, so skip any non-specialized 3553 // arguments. 3554 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) 3555 if (NonTypeTemplateParmDecl *NTTP 3556 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) { 3557 if (MirrorsPrimaryTemplate && 3558 (Param->getIndex() != NTTP->getIndex() || 3559 Param->getDepth() != NTTP->getDepth())) 3560 MirrorsPrimaryTemplate = false; 3561 3562 continue; 3563 } 3564 3565 // C++ [temp.class.spec]p9: 3566 // Within the argument list of a class template partial 3567 // specialization, the following restrictions apply: 3568 // -- A partially specialized non-type argument expression 3569 // shall not involve a template parameter of the partial 3570 // specialization except when the argument expression is a 3571 // simple identifier. 3572 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { 3573 Diag(ArgExpr->getLocStart(), 3574 diag::err_dependent_non_type_arg_in_partial_spec) 3575 << ArgExpr->getSourceRange(); 3576 return true; 3577 } 3578 3579 // -- The type of a template parameter corresponding to a 3580 // specialized non-type argument shall not be dependent on a 3581 // parameter of the specialization. 3582 if (Param->getType()->isDependentType()) { 3583 Diag(ArgExpr->getLocStart(), 3584 diag::err_dependent_typed_non_type_arg_in_partial_spec) 3585 << Param->getType() 3586 << ArgExpr->getSourceRange(); 3587 Diag(Param->getLocation(), diag::note_template_param_here); 3588 return true; 3589 } 3590 3591 MirrorsPrimaryTemplate = false; 3592 } 3593 3594 return false; 3595} 3596 3597/// \brief Retrieve the previous declaration of the given declaration. 3598static NamedDecl *getPreviousDecl(NamedDecl *ND) { 3599 if (VarDecl *VD = dyn_cast<VarDecl>(ND)) 3600 return VD->getPreviousDeclaration(); 3601 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) 3602 return FD->getPreviousDeclaration(); 3603 if (TagDecl *TD = dyn_cast<TagDecl>(ND)) 3604 return TD->getPreviousDeclaration(); 3605 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND)) 3606 return TD->getPreviousDeclaration(); 3607 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND)) 3608 return FTD->getPreviousDeclaration(); 3609 if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND)) 3610 return CTD->getPreviousDeclaration(); 3611 return 0; 3612} 3613 3614DeclResult 3615Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, 3616 TagUseKind TUK, 3617 SourceLocation KWLoc, 3618 CXXScopeSpec &SS, 3619 TemplateTy TemplateD, 3620 SourceLocation TemplateNameLoc, 3621 SourceLocation LAngleLoc, 3622 ASTTemplateArgsPtr TemplateArgsIn, 3623 SourceLocation RAngleLoc, 3624 AttributeList *Attr, 3625 MultiTemplateParamsArg TemplateParameterLists) { 3626 assert(TUK != TUK_Reference && "References are not specializations"); 3627 3628 // Find the class template we're specializing 3629 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 3630 ClassTemplateDecl *ClassTemplate 3631 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); 3632 3633 if (!ClassTemplate) { 3634 Diag(TemplateNameLoc, diag::err_not_class_template_specialization) 3635 << (Name.getAsTemplateDecl() && 3636 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); 3637 return true; 3638 } 3639 3640 bool isExplicitSpecialization = false; 3641 bool isPartialSpecialization = false; 3642 3643 // Check the validity of the template headers that introduce this 3644 // template. 3645 // FIXME: We probably shouldn't complain about these headers for 3646 // friend declarations. 3647 bool Invalid = false; 3648 TemplateParameterList *TemplateParams 3649 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS, 3650 (TemplateParameterList**)TemplateParameterLists.get(), 3651 TemplateParameterLists.size(), 3652 TUK == TUK_Friend, 3653 isExplicitSpecialization, 3654 Invalid); 3655 if (Invalid) 3656 return true; 3657 3658 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 3659 if (TemplateParams) 3660 --NumMatchedTemplateParamLists; 3661 3662 if (TemplateParams && TemplateParams->size() > 0) { 3663 isPartialSpecialization = true; 3664 3665 // C++ [temp.class.spec]p10: 3666 // The template parameter list of a specialization shall not 3667 // contain default template argument values. 3668 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3669 Decl *Param = TemplateParams->getParam(I); 3670 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { 3671 if (TTP->hasDefaultArgument()) { 3672 Diag(TTP->getDefaultArgumentLoc(), 3673 diag::err_default_arg_in_partial_spec); 3674 TTP->removeDefaultArgument(); 3675 } 3676 } else if (NonTypeTemplateParmDecl *NTTP 3677 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 3678 if (Expr *DefArg = NTTP->getDefaultArgument()) { 3679 Diag(NTTP->getDefaultArgumentLoc(), 3680 diag::err_default_arg_in_partial_spec) 3681 << DefArg->getSourceRange(); 3682 NTTP->removeDefaultArgument(); 3683 } 3684 } else { 3685 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); 3686 if (TTP->hasDefaultArgument()) { 3687 Diag(TTP->getDefaultArgument().getLocation(), 3688 diag::err_default_arg_in_partial_spec) 3689 << TTP->getDefaultArgument().getSourceRange(); 3690 TTP->removeDefaultArgument(); 3691 } 3692 } 3693 } 3694 } else if (TemplateParams) { 3695 if (TUK == TUK_Friend) 3696 Diag(KWLoc, diag::err_template_spec_friend) 3697 << FixItHint::CreateRemoval( 3698 SourceRange(TemplateParams->getTemplateLoc(), 3699 TemplateParams->getRAngleLoc())) 3700 << SourceRange(LAngleLoc, RAngleLoc); 3701 else 3702 isExplicitSpecialization = true; 3703 } else if (TUK != TUK_Friend) { 3704 Diag(KWLoc, diag::err_template_spec_needs_header) 3705 << FixItHint::CreateInsertion(KWLoc, "template<> "); 3706 isExplicitSpecialization = true; 3707 } 3708 3709 // Check that the specialization uses the same tag kind as the 3710 // original template. 3711 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 3712 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!"); 3713 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 3714 Kind, KWLoc, 3715 *ClassTemplate->getIdentifier())) { 3716 Diag(KWLoc, diag::err_use_with_wrong_tag) 3717 << ClassTemplate 3718 << FixItHint::CreateReplacement(KWLoc, 3719 ClassTemplate->getTemplatedDecl()->getKindName()); 3720 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 3721 diag::note_previous_use); 3722 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 3723 } 3724 3725 // Translate the parser's template argument list in our AST format. 3726 TemplateArgumentListInfo TemplateArgs; 3727 TemplateArgs.setLAngleLoc(LAngleLoc); 3728 TemplateArgs.setRAngleLoc(RAngleLoc); 3729 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 3730 3731 // Check that the template argument list is well-formed for this 3732 // template. 3733 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 3734 TemplateArgs.size()); 3735 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 3736 TemplateArgs, false, Converted)) 3737 return true; 3738 3739 assert((Converted.structuredSize() == 3740 ClassTemplate->getTemplateParameters()->size()) && 3741 "Converted template argument list is too short!"); 3742 3743 // Find the class template (partial) specialization declaration that 3744 // corresponds to these arguments. 3745 if (isPartialSpecialization) { 3746 bool MirrorsPrimaryTemplate; 3747 if (CheckClassTemplatePartialSpecializationArgs( 3748 ClassTemplate->getTemplateParameters(), 3749 Converted, MirrorsPrimaryTemplate)) 3750 return true; 3751 3752 if (MirrorsPrimaryTemplate) { 3753 // C++ [temp.class.spec]p9b3: 3754 // 3755 // -- The argument list of the specialization shall not be identical 3756 // to the implicit argument list of the primary template. 3757 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) 3758 << (TUK == TUK_Definition) 3759 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc)); 3760 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, 3761 ClassTemplate->getIdentifier(), 3762 TemplateNameLoc, 3763 Attr, 3764 TemplateParams, 3765 AS_none); 3766 } 3767 3768 // FIXME: Diagnose friend partial specializations 3769 3770 if (!Name.isDependent() && 3771 !TemplateSpecializationType::anyDependentTemplateArguments( 3772 TemplateArgs.getArgumentArray(), 3773 TemplateArgs.size())) { 3774 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized) 3775 << ClassTemplate->getDeclName(); 3776 isPartialSpecialization = false; 3777 } 3778 } 3779 3780 void *InsertPos = 0; 3781 ClassTemplateSpecializationDecl *PrevDecl = 0; 3782 3783 if (isPartialSpecialization) 3784 // FIXME: Template parameter list matters, too 3785 PrevDecl 3786 = ClassTemplate->findPartialSpecialization(Converted.getFlatArguments(), 3787 Converted.flatSize(), 3788 InsertPos); 3789 else 3790 PrevDecl 3791 = ClassTemplate->findSpecialization(Converted.getFlatArguments(), 3792 Converted.flatSize(), InsertPos); 3793 3794 ClassTemplateSpecializationDecl *Specialization = 0; 3795 3796 // Check whether we can declare a class template specialization in 3797 // the current scope. 3798 if (TUK != TUK_Friend && 3799 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, 3800 TemplateNameLoc, 3801 isPartialSpecialization)) 3802 return true; 3803 3804 // The canonical type 3805 QualType CanonType; 3806 if (PrevDecl && 3807 (PrevDecl->getSpecializationKind() == TSK_Undeclared || 3808 TUK == TUK_Friend)) { 3809 // Since the only prior class template specialization with these 3810 // arguments was referenced but not declared, or we're only 3811 // referencing this specialization as a friend, reuse that 3812 // declaration node as our own, updating its source location to 3813 // reflect our new declaration. 3814 Specialization = PrevDecl; 3815 Specialization->setLocation(TemplateNameLoc); 3816 PrevDecl = 0; 3817 CanonType = Context.getTypeDeclType(Specialization); 3818 } else if (isPartialSpecialization) { 3819 // Build the canonical type that describes the converted template 3820 // arguments of the class template partial specialization. 3821 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); 3822 CanonType = Context.getTemplateSpecializationType(CanonTemplate, 3823 Converted.getFlatArguments(), 3824 Converted.flatSize()); 3825 3826 // Create a new class template partial specialization declaration node. 3827 ClassTemplatePartialSpecializationDecl *PrevPartial 3828 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); 3829 unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber() 3830 : ClassTemplate->getNextPartialSpecSequenceNumber(); 3831 ClassTemplatePartialSpecializationDecl *Partial 3832 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind, 3833 ClassTemplate->getDeclContext(), 3834 TemplateNameLoc, 3835 TemplateParams, 3836 ClassTemplate, 3837 Converted, 3838 TemplateArgs, 3839 CanonType, 3840 PrevPartial, 3841 SequenceNumber); 3842 SetNestedNameSpecifier(Partial, SS); 3843 if (NumMatchedTemplateParamLists > 0 && SS.isSet()) { 3844 Partial->setTemplateParameterListsInfo(Context, 3845 NumMatchedTemplateParamLists, 3846 (TemplateParameterList**) TemplateParameterLists.release()); 3847 } 3848 3849 if (!PrevPartial) 3850 ClassTemplate->AddPartialSpecialization(Partial, InsertPos); 3851 Specialization = Partial; 3852 3853 // If we are providing an explicit specialization of a member class 3854 // template specialization, make a note of that. 3855 if (PrevPartial && PrevPartial->getInstantiatedFromMember()) 3856 PrevPartial->setMemberSpecialization(); 3857 3858 // Check that all of the template parameters of the class template 3859 // partial specialization are deducible from the template 3860 // arguments. If not, this class template partial specialization 3861 // will never be used. 3862 llvm::SmallVector<bool, 8> DeducibleParams; 3863 DeducibleParams.resize(TemplateParams->size()); 3864 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true, 3865 TemplateParams->getDepth(), 3866 DeducibleParams); 3867 unsigned NumNonDeducible = 0; 3868 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) 3869 if (!DeducibleParams[I]) 3870 ++NumNonDeducible; 3871 3872 if (NumNonDeducible) { 3873 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible) 3874 << (NumNonDeducible > 1) 3875 << SourceRange(TemplateNameLoc, RAngleLoc); 3876 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) { 3877 if (!DeducibleParams[I]) { 3878 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I)); 3879 if (Param->getDeclName()) 3880 Diag(Param->getLocation(), 3881 diag::note_partial_spec_unused_parameter) 3882 << Param->getDeclName(); 3883 else 3884 Diag(Param->getLocation(), 3885 diag::note_partial_spec_unused_parameter) 3886 << "<anonymous>"; 3887 } 3888 } 3889 } 3890 } else { 3891 // Create a new class template specialization declaration node for 3892 // this explicit specialization or friend declaration. 3893 Specialization 3894 = ClassTemplateSpecializationDecl::Create(Context, Kind, 3895 ClassTemplate->getDeclContext(), 3896 TemplateNameLoc, 3897 ClassTemplate, 3898 Converted, 3899 PrevDecl); 3900 SetNestedNameSpecifier(Specialization, SS); 3901 if (NumMatchedTemplateParamLists > 0 && SS.isSet()) { 3902 Specialization->setTemplateParameterListsInfo(Context, 3903 NumMatchedTemplateParamLists, 3904 (TemplateParameterList**) TemplateParameterLists.release()); 3905 } 3906 3907 if (!PrevDecl) 3908 ClassTemplate->AddSpecialization(Specialization, InsertPos); 3909 3910 CanonType = Context.getTypeDeclType(Specialization); 3911 } 3912 3913 // C++ [temp.expl.spec]p6: 3914 // If a template, a member template or the member of a class template is 3915 // explicitly specialized then that specialization shall be declared 3916 // before the first use of that specialization that would cause an implicit 3917 // instantiation to take place, in every translation unit in which such a 3918 // use occurs; no diagnostic is required. 3919 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { 3920 bool Okay = false; 3921 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 3922 // Is there any previous explicit specialization declaration? 3923 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) { 3924 Okay = true; 3925 break; 3926 } 3927 } 3928 3929 if (!Okay) { 3930 SourceRange Range(TemplateNameLoc, RAngleLoc); 3931 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) 3932 << Context.getTypeDeclType(Specialization) << Range; 3933 3934 Diag(PrevDecl->getPointOfInstantiation(), 3935 diag::note_instantiation_required_here) 3936 << (PrevDecl->getTemplateSpecializationKind() 3937 != TSK_ImplicitInstantiation); 3938 return true; 3939 } 3940 } 3941 3942 // If this is not a friend, note that this is an explicit specialization. 3943 if (TUK != TUK_Friend) 3944 Specialization->setSpecializationKind(TSK_ExplicitSpecialization); 3945 3946 // Check that this isn't a redefinition of this specialization. 3947 if (TUK == TUK_Definition) { 3948 if (RecordDecl *Def = Specialization->getDefinition()) { 3949 SourceRange Range(TemplateNameLoc, RAngleLoc); 3950 Diag(TemplateNameLoc, diag::err_redefinition) 3951 << Context.getTypeDeclType(Specialization) << Range; 3952 Diag(Def->getLocation(), diag::note_previous_definition); 3953 Specialization->setInvalidDecl(); 3954 return true; 3955 } 3956 } 3957 3958 // Build the fully-sugared type for this class template 3959 // specialization as the user wrote in the specialization 3960 // itself. This means that we'll pretty-print the type retrieved 3961 // from the specialization's declaration the way that the user 3962 // actually wrote the specialization, rather than formatting the 3963 // name based on the "canonical" representation used to store the 3964 // template arguments in the specialization. 3965 TypeSourceInfo *WrittenTy 3966 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 3967 TemplateArgs, CanonType); 3968 if (TUK != TUK_Friend) { 3969 Specialization->setTypeAsWritten(WrittenTy); 3970 if (TemplateParams) 3971 Specialization->setTemplateKeywordLoc(TemplateParams->getTemplateLoc()); 3972 } 3973 TemplateArgsIn.release(); 3974 3975 // C++ [temp.expl.spec]p9: 3976 // A template explicit specialization is in the scope of the 3977 // namespace in which the template was defined. 3978 // 3979 // We actually implement this paragraph where we set the semantic 3980 // context (in the creation of the ClassTemplateSpecializationDecl), 3981 // but we also maintain the lexical context where the actual 3982 // definition occurs. 3983 Specialization->setLexicalDeclContext(CurContext); 3984 3985 // We may be starting the definition of this specialization. 3986 if (TUK == TUK_Definition) 3987 Specialization->startDefinition(); 3988 3989 if (TUK == TUK_Friend) { 3990 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 3991 TemplateNameLoc, 3992 WrittenTy, 3993 /*FIXME:*/KWLoc); 3994 Friend->setAccess(AS_public); 3995 CurContext->addDecl(Friend); 3996 } else { 3997 // Add the specialization into its lexical context, so that it can 3998 // be seen when iterating through the list of declarations in that 3999 // context. However, specializations are not found by name lookup. 4000 CurContext->addDecl(Specialization); 4001 } 4002 return Specialization; 4003} 4004 4005Decl *Sema::ActOnTemplateDeclarator(Scope *S, 4006 MultiTemplateParamsArg TemplateParameterLists, 4007 Declarator &D) { 4008 return HandleDeclarator(S, D, move(TemplateParameterLists), false); 4009} 4010 4011Decl *Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, 4012 MultiTemplateParamsArg TemplateParameterLists, 4013 Declarator &D) { 4014 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4015 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4016 "Not a function declarator!"); 4017 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4018 4019 if (FTI.hasPrototype) { 4020 // FIXME: Diagnose arguments without names in C. 4021 } 4022 4023 Scope *ParentScope = FnBodyScope->getParent(); 4024 4025 Decl *DP = HandleDeclarator(ParentScope, D, 4026 move(TemplateParameterLists), 4027 /*IsFunctionDefinition=*/true); 4028 if (FunctionTemplateDecl *FunctionTemplate 4029 = dyn_cast_or_null<FunctionTemplateDecl>(DP)) 4030 return ActOnStartOfFunctionDef(FnBodyScope, 4031 FunctionTemplate->getTemplatedDecl()); 4032 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP)) 4033 return ActOnStartOfFunctionDef(FnBodyScope, Function); 4034 return 0; 4035} 4036 4037/// \brief Strips various properties off an implicit instantiation 4038/// that has just been explicitly specialized. 4039static void StripImplicitInstantiation(NamedDecl *D) { 4040 D->dropAttrs(); 4041 4042 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 4043 FD->setInlineSpecified(false); 4044 } 4045} 4046 4047/// \brief Diagnose cases where we have an explicit template specialization 4048/// before/after an explicit template instantiation, producing diagnostics 4049/// for those cases where they are required and determining whether the 4050/// new specialization/instantiation will have any effect. 4051/// 4052/// \param NewLoc the location of the new explicit specialization or 4053/// instantiation. 4054/// 4055/// \param NewTSK the kind of the new explicit specialization or instantiation. 4056/// 4057/// \param PrevDecl the previous declaration of the entity. 4058/// 4059/// \param PrevTSK the kind of the old explicit specialization or instantiatin. 4060/// 4061/// \param PrevPointOfInstantiation if valid, indicates where the previus 4062/// declaration was instantiated (either implicitly or explicitly). 4063/// 4064/// \param HasNoEffect will be set to true to indicate that the new 4065/// specialization or instantiation has no effect and should be ignored. 4066/// 4067/// \returns true if there was an error that should prevent the introduction of 4068/// the new declaration into the AST, false otherwise. 4069bool 4070Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, 4071 TemplateSpecializationKind NewTSK, 4072 NamedDecl *PrevDecl, 4073 TemplateSpecializationKind PrevTSK, 4074 SourceLocation PrevPointOfInstantiation, 4075 bool &HasNoEffect) { 4076 HasNoEffect = false; 4077 4078 switch (NewTSK) { 4079 case TSK_Undeclared: 4080 case TSK_ImplicitInstantiation: 4081 assert(false && "Don't check implicit instantiations here"); 4082 return false; 4083 4084 case TSK_ExplicitSpecialization: 4085 switch (PrevTSK) { 4086 case TSK_Undeclared: 4087 case TSK_ExplicitSpecialization: 4088 // Okay, we're just specializing something that is either already 4089 // explicitly specialized or has merely been mentioned without any 4090 // instantiation. 4091 return false; 4092 4093 case TSK_ImplicitInstantiation: 4094 if (PrevPointOfInstantiation.isInvalid()) { 4095 // The declaration itself has not actually been instantiated, so it is 4096 // still okay to specialize it. 4097 StripImplicitInstantiation(PrevDecl); 4098 return false; 4099 } 4100 // Fall through 4101 4102 case TSK_ExplicitInstantiationDeclaration: 4103 case TSK_ExplicitInstantiationDefinition: 4104 assert((PrevTSK == TSK_ImplicitInstantiation || 4105 PrevPointOfInstantiation.isValid()) && 4106 "Explicit instantiation without point of instantiation?"); 4107 4108 // C++ [temp.expl.spec]p6: 4109 // If a template, a member template or the member of a class template 4110 // is explicitly specialized then that specialization shall be declared 4111 // before the first use of that specialization that would cause an 4112 // implicit instantiation to take place, in every translation unit in 4113 // which such a use occurs; no diagnostic is required. 4114 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 4115 // Is there any previous explicit specialization declaration? 4116 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) 4117 return false; 4118 } 4119 4120 Diag(NewLoc, diag::err_specialization_after_instantiation) 4121 << PrevDecl; 4122 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) 4123 << (PrevTSK != TSK_ImplicitInstantiation); 4124 4125 return true; 4126 } 4127 break; 4128 4129 case TSK_ExplicitInstantiationDeclaration: 4130 switch (PrevTSK) { 4131 case TSK_ExplicitInstantiationDeclaration: 4132 // This explicit instantiation declaration is redundant (that's okay). 4133 HasNoEffect = true; 4134 return false; 4135 4136 case TSK_Undeclared: 4137 case TSK_ImplicitInstantiation: 4138 // We're explicitly instantiating something that may have already been 4139 // implicitly instantiated; that's fine. 4140 return false; 4141 4142 case TSK_ExplicitSpecialization: 4143 // C++0x [temp.explicit]p4: 4144 // For a given set of template parameters, if an explicit instantiation 4145 // of a template appears after a declaration of an explicit 4146 // specialization for that template, the explicit instantiation has no 4147 // effect. 4148 HasNoEffect = true; 4149 return false; 4150 4151 case TSK_ExplicitInstantiationDefinition: 4152 // C++0x [temp.explicit]p10: 4153 // If an entity is the subject of both an explicit instantiation 4154 // declaration and an explicit instantiation definition in the same 4155 // translation unit, the definition shall follow the declaration. 4156 Diag(NewLoc, 4157 diag::err_explicit_instantiation_declaration_after_definition); 4158 Diag(PrevPointOfInstantiation, 4159 diag::note_explicit_instantiation_definition_here); 4160 assert(PrevPointOfInstantiation.isValid() && 4161 "Explicit instantiation without point of instantiation?"); 4162 HasNoEffect = true; 4163 return false; 4164 } 4165 break; 4166 4167 case TSK_ExplicitInstantiationDefinition: 4168 switch (PrevTSK) { 4169 case TSK_Undeclared: 4170 case TSK_ImplicitInstantiation: 4171 // We're explicitly instantiating something that may have already been 4172 // implicitly instantiated; that's fine. 4173 return false; 4174 4175 case TSK_ExplicitSpecialization: 4176 // C++ DR 259, C++0x [temp.explicit]p4: 4177 // For a given set of template parameters, if an explicit 4178 // instantiation of a template appears after a declaration of 4179 // an explicit specialization for that template, the explicit 4180 // instantiation has no effect. 4181 // 4182 // In C++98/03 mode, we only give an extension warning here, because it 4183 // is not harmful to try to explicitly instantiate something that 4184 // has been explicitly specialized. 4185 if (!getLangOptions().CPlusPlus0x) { 4186 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization) 4187 << PrevDecl; 4188 Diag(PrevDecl->getLocation(), 4189 diag::note_previous_template_specialization); 4190 } 4191 HasNoEffect = true; 4192 return false; 4193 4194 case TSK_ExplicitInstantiationDeclaration: 4195 // We're explicity instantiating a definition for something for which we 4196 // were previously asked to suppress instantiations. That's fine. 4197 return false; 4198 4199 case TSK_ExplicitInstantiationDefinition: 4200 // C++0x [temp.spec]p5: 4201 // For a given template and a given set of template-arguments, 4202 // - an explicit instantiation definition shall appear at most once 4203 // in a program, 4204 Diag(NewLoc, diag::err_explicit_instantiation_duplicate) 4205 << PrevDecl; 4206 Diag(PrevPointOfInstantiation, 4207 diag::note_previous_explicit_instantiation); 4208 HasNoEffect = true; 4209 return false; 4210 } 4211 break; 4212 } 4213 4214 assert(false && "Missing specialization/instantiation case?"); 4215 4216 return false; 4217} 4218 4219/// \brief Perform semantic analysis for the given dependent function 4220/// template specialization. The only possible way to get a dependent 4221/// function template specialization is with a friend declaration, 4222/// like so: 4223/// 4224/// template <class T> void foo(T); 4225/// template <class T> class A { 4226/// friend void foo<>(T); 4227/// }; 4228/// 4229/// There really isn't any useful analysis we can do here, so we 4230/// just store the information. 4231bool 4232Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD, 4233 const TemplateArgumentListInfo &ExplicitTemplateArgs, 4234 LookupResult &Previous) { 4235 // Remove anything from Previous that isn't a function template in 4236 // the correct context. 4237 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext(); 4238 LookupResult::Filter F = Previous.makeFilter(); 4239 while (F.hasNext()) { 4240 NamedDecl *D = F.next()->getUnderlyingDecl(); 4241 if (!isa<FunctionTemplateDecl>(D) || 4242 !FDLookupContext->InEnclosingNamespaceSetOf( 4243 D->getDeclContext()->getRedeclContext())) 4244 F.erase(); 4245 } 4246 F.done(); 4247 4248 // Should this be diagnosed here? 4249 if (Previous.empty()) return true; 4250 4251 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(), 4252 ExplicitTemplateArgs); 4253 return false; 4254} 4255 4256/// \brief Perform semantic analysis for the given function template 4257/// specialization. 4258/// 4259/// This routine performs all of the semantic analysis required for an 4260/// explicit function template specialization. On successful completion, 4261/// the function declaration \p FD will become a function template 4262/// specialization. 4263/// 4264/// \param FD the function declaration, which will be updated to become a 4265/// function template specialization. 4266/// 4267/// \param ExplicitTemplateArgs the explicitly-provided template arguments, 4268/// if any. Note that this may be valid info even when 0 arguments are 4269/// explicitly provided as in, e.g., \c void sort<>(char*, char*); 4270/// as it anyway contains info on the angle brackets locations. 4271/// 4272/// \param PrevDecl the set of declarations that may be specialized by 4273/// this function specialization. 4274bool 4275Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, 4276 const TemplateArgumentListInfo *ExplicitTemplateArgs, 4277 LookupResult &Previous) { 4278 // The set of function template specializations that could match this 4279 // explicit function template specialization. 4280 UnresolvedSet<8> Candidates; 4281 4282 DeclContext *FDLookupContext = FD->getDeclContext()->getRedeclContext(); 4283 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4284 I != E; ++I) { 4285 NamedDecl *Ovl = (*I)->getUnderlyingDecl(); 4286 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { 4287 // Only consider templates found within the same semantic lookup scope as 4288 // FD. 4289 if (!FDLookupContext->InEnclosingNamespaceSetOf( 4290 Ovl->getDeclContext()->getRedeclContext())) 4291 continue; 4292 4293 // C++ [temp.expl.spec]p11: 4294 // A trailing template-argument can be left unspecified in the 4295 // template-id naming an explicit function template specialization 4296 // provided it can be deduced from the function argument type. 4297 // Perform template argument deduction to determine whether we may be 4298 // specializing this template. 4299 // FIXME: It is somewhat wasteful to build 4300 TemplateDeductionInfo Info(Context, FD->getLocation()); 4301 FunctionDecl *Specialization = 0; 4302 if (TemplateDeductionResult TDK 4303 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, 4304 FD->getType(), 4305 Specialization, 4306 Info)) { 4307 // FIXME: Template argument deduction failed; record why it failed, so 4308 // that we can provide nifty diagnostics. 4309 (void)TDK; 4310 continue; 4311 } 4312 4313 // Record this candidate. 4314 Candidates.addDecl(Specialization, I.getAccess()); 4315 } 4316 } 4317 4318 // Find the most specialized function template. 4319 UnresolvedSetIterator Result 4320 = getMostSpecialized(Candidates.begin(), Candidates.end(), 4321 TPOC_Other, FD->getLocation(), 4322 PDiag(diag::err_function_template_spec_no_match) 4323 << FD->getDeclName(), 4324 PDiag(diag::err_function_template_spec_ambiguous) 4325 << FD->getDeclName() << (ExplicitTemplateArgs != 0), 4326 PDiag(diag::note_function_template_spec_matched)); 4327 if (Result == Candidates.end()) 4328 return true; 4329 4330 // Ignore access information; it doesn't figure into redeclaration checking. 4331 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 4332 Specialization->setLocation(FD->getLocation()); 4333 4334 // FIXME: Check if the prior specialization has a point of instantiation. 4335 // If so, we have run afoul of . 4336 4337 // If this is a friend declaration, then we're not really declaring 4338 // an explicit specialization. 4339 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None); 4340 4341 // Check the scope of this explicit specialization. 4342 if (!isFriend && 4343 CheckTemplateSpecializationScope(*this, 4344 Specialization->getPrimaryTemplate(), 4345 Specialization, FD->getLocation(), 4346 false)) 4347 return true; 4348 4349 // C++ [temp.expl.spec]p6: 4350 // If a template, a member template or the member of a class template is 4351 // explicitly specialized then that specialization shall be declared 4352 // before the first use of that specialization that would cause an implicit 4353 // instantiation to take place, in every translation unit in which such a 4354 // use occurs; no diagnostic is required. 4355 FunctionTemplateSpecializationInfo *SpecInfo 4356 = Specialization->getTemplateSpecializationInfo(); 4357 assert(SpecInfo && "Function template specialization info missing?"); 4358 4359 bool HasNoEffect = false; 4360 if (!isFriend && 4361 CheckSpecializationInstantiationRedecl(FD->getLocation(), 4362 TSK_ExplicitSpecialization, 4363 Specialization, 4364 SpecInfo->getTemplateSpecializationKind(), 4365 SpecInfo->getPointOfInstantiation(), 4366 HasNoEffect)) 4367 return true; 4368 4369 // Mark the prior declaration as an explicit specialization, so that later 4370 // clients know that this is an explicit specialization. 4371 if (!isFriend) { 4372 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); 4373 MarkUnusedFileScopedDecl(Specialization); 4374 } 4375 4376 // Turn the given function declaration into a function template 4377 // specialization, with the template arguments from the previous 4378 // specialization. 4379 // Take copies of (semantic and syntactic) template argument lists. 4380 const TemplateArgumentList* TemplArgs = new (Context) 4381 TemplateArgumentList(Specialization->getTemplateSpecializationArgs()); 4382 const TemplateArgumentListInfo* TemplArgsAsWritten = ExplicitTemplateArgs 4383 ? new (Context) TemplateArgumentListInfo(*ExplicitTemplateArgs) : 0; 4384 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(), 4385 TemplArgs, /*InsertPos=*/0, 4386 SpecInfo->getTemplateSpecializationKind(), 4387 TemplArgsAsWritten); 4388 4389 // The "previous declaration" for this function template specialization is 4390 // the prior function template specialization. 4391 Previous.clear(); 4392 Previous.addDecl(Specialization); 4393 return false; 4394} 4395 4396/// \brief Perform semantic analysis for the given non-template member 4397/// specialization. 4398/// 4399/// This routine performs all of the semantic analysis required for an 4400/// explicit member function specialization. On successful completion, 4401/// the function declaration \p FD will become a member function 4402/// specialization. 4403/// 4404/// \param Member the member declaration, which will be updated to become a 4405/// specialization. 4406/// 4407/// \param Previous the set of declarations, one of which may be specialized 4408/// by this function specialization; the set will be modified to contain the 4409/// redeclared member. 4410bool 4411Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { 4412 assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); 4413 4414 // Try to find the member we are instantiating. 4415 NamedDecl *Instantiation = 0; 4416 NamedDecl *InstantiatedFrom = 0; 4417 MemberSpecializationInfo *MSInfo = 0; 4418 4419 if (Previous.empty()) { 4420 // Nowhere to look anyway. 4421 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { 4422 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4423 I != E; ++I) { 4424 NamedDecl *D = (*I)->getUnderlyingDecl(); 4425 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 4426 if (Context.hasSameType(Function->getType(), Method->getType())) { 4427 Instantiation = Method; 4428 InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); 4429 MSInfo = Method->getMemberSpecializationInfo(); 4430 break; 4431 } 4432 } 4433 } 4434 } else if (isa<VarDecl>(Member)) { 4435 VarDecl *PrevVar; 4436 if (Previous.isSingleResult() && 4437 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) 4438 if (PrevVar->isStaticDataMember()) { 4439 Instantiation = PrevVar; 4440 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); 4441 MSInfo = PrevVar->getMemberSpecializationInfo(); 4442 } 4443 } else if (isa<RecordDecl>(Member)) { 4444 CXXRecordDecl *PrevRecord; 4445 if (Previous.isSingleResult() && 4446 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { 4447 Instantiation = PrevRecord; 4448 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); 4449 MSInfo = PrevRecord->getMemberSpecializationInfo(); 4450 } 4451 } 4452 4453 if (!Instantiation) { 4454 // There is no previous declaration that matches. Since member 4455 // specializations are always out-of-line, the caller will complain about 4456 // this mismatch later. 4457 return false; 4458 } 4459 4460 // If this is a friend, just bail out here before we start turning 4461 // things into explicit specializations. 4462 if (Member->getFriendObjectKind() != Decl::FOK_None) { 4463 // Preserve instantiation information. 4464 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) { 4465 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction( 4466 cast<CXXMethodDecl>(InstantiatedFrom), 4467 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind()); 4468 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) { 4469 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4470 cast<CXXRecordDecl>(InstantiatedFrom), 4471 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind()); 4472 } 4473 4474 Previous.clear(); 4475 Previous.addDecl(Instantiation); 4476 return false; 4477 } 4478 4479 // Make sure that this is a specialization of a member. 4480 if (!InstantiatedFrom) { 4481 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) 4482 << Member; 4483 Diag(Instantiation->getLocation(), diag::note_specialized_decl); 4484 return true; 4485 } 4486 4487 // C++ [temp.expl.spec]p6: 4488 // If a template, a member template or the member of a class template is 4489 // explicitly specialized then that spe- cialization shall be declared 4490 // before the first use of that specialization that would cause an implicit 4491 // instantiation to take place, in every translation unit in which such a 4492 // use occurs; no diagnostic is required. 4493 assert(MSInfo && "Member specialization info missing?"); 4494 4495 bool HasNoEffect = false; 4496 if (CheckSpecializationInstantiationRedecl(Member->getLocation(), 4497 TSK_ExplicitSpecialization, 4498 Instantiation, 4499 MSInfo->getTemplateSpecializationKind(), 4500 MSInfo->getPointOfInstantiation(), 4501 HasNoEffect)) 4502 return true; 4503 4504 // Check the scope of this explicit specialization. 4505 if (CheckTemplateSpecializationScope(*this, 4506 InstantiatedFrom, 4507 Instantiation, Member->getLocation(), 4508 false)) 4509 return true; 4510 4511 // Note that this is an explicit instantiation of a member. 4512 // the original declaration to note that it is an explicit specialization 4513 // (if it was previously an implicit instantiation). This latter step 4514 // makes bookkeeping easier. 4515 if (isa<FunctionDecl>(Member)) { 4516 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); 4517 if (InstantiationFunction->getTemplateSpecializationKind() == 4518 TSK_ImplicitInstantiation) { 4519 InstantiationFunction->setTemplateSpecializationKind( 4520 TSK_ExplicitSpecialization); 4521 InstantiationFunction->setLocation(Member->getLocation()); 4522 } 4523 4524 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( 4525 cast<CXXMethodDecl>(InstantiatedFrom), 4526 TSK_ExplicitSpecialization); 4527 MarkUnusedFileScopedDecl(InstantiationFunction); 4528 } else if (isa<VarDecl>(Member)) { 4529 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); 4530 if (InstantiationVar->getTemplateSpecializationKind() == 4531 TSK_ImplicitInstantiation) { 4532 InstantiationVar->setTemplateSpecializationKind( 4533 TSK_ExplicitSpecialization); 4534 InstantiationVar->setLocation(Member->getLocation()); 4535 } 4536 4537 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), 4538 cast<VarDecl>(InstantiatedFrom), 4539 TSK_ExplicitSpecialization); 4540 MarkUnusedFileScopedDecl(InstantiationVar); 4541 } else { 4542 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain"); 4543 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); 4544 if (InstantiationClass->getTemplateSpecializationKind() == 4545 TSK_ImplicitInstantiation) { 4546 InstantiationClass->setTemplateSpecializationKind( 4547 TSK_ExplicitSpecialization); 4548 InstantiationClass->setLocation(Member->getLocation()); 4549 } 4550 4551 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4552 cast<CXXRecordDecl>(InstantiatedFrom), 4553 TSK_ExplicitSpecialization); 4554 } 4555 4556 // Save the caller the trouble of having to figure out which declaration 4557 // this specialization matches. 4558 Previous.clear(); 4559 Previous.addDecl(Instantiation); 4560 return false; 4561} 4562 4563/// \brief Check the scope of an explicit instantiation. 4564/// 4565/// \returns true if a serious error occurs, false otherwise. 4566static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, 4567 SourceLocation InstLoc, 4568 bool WasQualifiedName) { 4569 DeclContext *OrigContext= D->getDeclContext()->getEnclosingNamespaceContext(); 4570 DeclContext *CurContext = S.CurContext->getRedeclContext(); 4571 4572 if (CurContext->isRecord()) { 4573 S.Diag(InstLoc, diag::err_explicit_instantiation_in_class) 4574 << D; 4575 return true; 4576 } 4577 4578 // C++0x [temp.explicit]p2: 4579 // An explicit instantiation shall appear in an enclosing namespace of its 4580 // template. 4581 // 4582 // This is DR275, which we do not retroactively apply to C++98/03. 4583 if (S.getLangOptions().CPlusPlus0x && 4584 !CurContext->Encloses(OrigContext)) { 4585 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(OrigContext)) 4586 S.Diag(InstLoc, 4587 S.getLangOptions().CPlusPlus0x? 4588 diag::err_explicit_instantiation_out_of_scope 4589 : diag::warn_explicit_instantiation_out_of_scope_0x) 4590 << D << NS; 4591 else 4592 S.Diag(InstLoc, 4593 S.getLangOptions().CPlusPlus0x? 4594 diag::err_explicit_instantiation_must_be_global 4595 : diag::warn_explicit_instantiation_out_of_scope_0x) 4596 << D; 4597 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4598 return false; 4599 } 4600 4601 // C++0x [temp.explicit]p2: 4602 // If the name declared in the explicit instantiation is an unqualified 4603 // name, the explicit instantiation shall appear in the namespace where 4604 // its template is declared or, if that namespace is inline (7.3.1), any 4605 // namespace from its enclosing namespace set. 4606 if (WasQualifiedName) 4607 return false; 4608 4609 if (CurContext->InEnclosingNamespaceSetOf(OrigContext)) 4610 return false; 4611 4612 S.Diag(InstLoc, 4613 S.getLangOptions().CPlusPlus0x? 4614 diag::err_explicit_instantiation_unqualified_wrong_namespace 4615 : diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x) 4616 << D << OrigContext; 4617 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4618 return false; 4619} 4620 4621/// \brief Determine whether the given scope specifier has a template-id in it. 4622static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { 4623 if (!SS.isSet()) 4624 return false; 4625 4626 // C++0x [temp.explicit]p2: 4627 // If the explicit instantiation is for a member function, a member class 4628 // or a static data member of a class template specialization, the name of 4629 // the class template specialization in the qualified-id for the member 4630 // name shall be a simple-template-id. 4631 // 4632 // C++98 has the same restriction, just worded differently. 4633 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 4634 NNS; NNS = NNS->getPrefix()) 4635 if (Type *T = NNS->getAsType()) 4636 if (isa<TemplateSpecializationType>(T)) 4637 return true; 4638 4639 return false; 4640} 4641 4642// Explicit instantiation of a class template specialization 4643DeclResult 4644Sema::ActOnExplicitInstantiation(Scope *S, 4645 SourceLocation ExternLoc, 4646 SourceLocation TemplateLoc, 4647 unsigned TagSpec, 4648 SourceLocation KWLoc, 4649 const CXXScopeSpec &SS, 4650 TemplateTy TemplateD, 4651 SourceLocation TemplateNameLoc, 4652 SourceLocation LAngleLoc, 4653 ASTTemplateArgsPtr TemplateArgsIn, 4654 SourceLocation RAngleLoc, 4655 AttributeList *Attr) { 4656 // Find the class template we're specializing 4657 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 4658 ClassTemplateDecl *ClassTemplate 4659 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); 4660 4661 // Check that the specialization uses the same tag kind as the 4662 // original template. 4663 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 4664 assert(Kind != TTK_Enum && 4665 "Invalid enum tag in class template explicit instantiation!"); 4666 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 4667 Kind, KWLoc, 4668 *ClassTemplate->getIdentifier())) { 4669 Diag(KWLoc, diag::err_use_with_wrong_tag) 4670 << ClassTemplate 4671 << FixItHint::CreateReplacement(KWLoc, 4672 ClassTemplate->getTemplatedDecl()->getKindName()); 4673 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 4674 diag::note_previous_use); 4675 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 4676 } 4677 4678 // C++0x [temp.explicit]p2: 4679 // There are two forms of explicit instantiation: an explicit instantiation 4680 // definition and an explicit instantiation declaration. An explicit 4681 // instantiation declaration begins with the extern keyword. [...] 4682 TemplateSpecializationKind TSK 4683 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4684 : TSK_ExplicitInstantiationDeclaration; 4685 4686 // Translate the parser's template argument list in our AST format. 4687 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 4688 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 4689 4690 // Check that the template argument list is well-formed for this 4691 // template. 4692 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 4693 TemplateArgs.size()); 4694 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 4695 TemplateArgs, false, Converted)) 4696 return true; 4697 4698 assert((Converted.structuredSize() == 4699 ClassTemplate->getTemplateParameters()->size()) && 4700 "Converted template argument list is too short!"); 4701 4702 // Find the class template specialization declaration that 4703 // corresponds to these arguments. 4704 void *InsertPos = 0; 4705 ClassTemplateSpecializationDecl *PrevDecl 4706 = ClassTemplate->findSpecialization(Converted.getFlatArguments(), 4707 Converted.flatSize(), InsertPos); 4708 4709 TemplateSpecializationKind PrevDecl_TSK 4710 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared; 4711 4712 // C++0x [temp.explicit]p2: 4713 // [...] An explicit instantiation shall appear in an enclosing 4714 // namespace of its template. [...] 4715 // 4716 // This is C++ DR 275. 4717 if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, 4718 SS.isSet())) 4719 return true; 4720 4721 ClassTemplateSpecializationDecl *Specialization = 0; 4722 4723 bool ReusedDecl = false; 4724 bool HasNoEffect = false; 4725 if (PrevDecl) { 4726 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, 4727 PrevDecl, PrevDecl_TSK, 4728 PrevDecl->getPointOfInstantiation(), 4729 HasNoEffect)) 4730 return PrevDecl; 4731 4732 // Even though HasNoEffect == true means that this explicit instantiation 4733 // has no effect on semantics, we go on to put its syntax in the AST. 4734 4735 if (PrevDecl_TSK == TSK_ImplicitInstantiation || 4736 PrevDecl_TSK == TSK_Undeclared) { 4737 // Since the only prior class template specialization with these 4738 // arguments was referenced but not declared, reuse that 4739 // declaration node as our own, updating the source location 4740 // for the template name to reflect our new declaration. 4741 // (Other source locations will be updated later.) 4742 Specialization = PrevDecl; 4743 Specialization->setLocation(TemplateNameLoc); 4744 PrevDecl = 0; 4745 ReusedDecl = true; 4746 } 4747 } 4748 4749 if (!Specialization) { 4750 // Create a new class template specialization declaration node for 4751 // this explicit specialization. 4752 Specialization 4753 = ClassTemplateSpecializationDecl::Create(Context, Kind, 4754 ClassTemplate->getDeclContext(), 4755 TemplateNameLoc, 4756 ClassTemplate, 4757 Converted, PrevDecl); 4758 SetNestedNameSpecifier(Specialization, SS); 4759 4760 if (!HasNoEffect && !PrevDecl) { 4761 // Insert the new specialization. 4762 ClassTemplate->AddSpecialization(Specialization, InsertPos); 4763 } 4764 } 4765 4766 // Build the fully-sugared type for this explicit instantiation as 4767 // the user wrote in the explicit instantiation itself. This means 4768 // that we'll pretty-print the type retrieved from the 4769 // specialization's declaration the way that the user actually wrote 4770 // the explicit instantiation, rather than formatting the name based 4771 // on the "canonical" representation used to store the template 4772 // arguments in the specialization. 4773 TypeSourceInfo *WrittenTy 4774 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 4775 TemplateArgs, 4776 Context.getTypeDeclType(Specialization)); 4777 Specialization->setTypeAsWritten(WrittenTy); 4778 TemplateArgsIn.release(); 4779 4780 // Set source locations for keywords. 4781 Specialization->setExternLoc(ExternLoc); 4782 Specialization->setTemplateKeywordLoc(TemplateLoc); 4783 4784 // Add the explicit instantiation into its lexical context. However, 4785 // since explicit instantiations are never found by name lookup, we 4786 // just put it into the declaration context directly. 4787 Specialization->setLexicalDeclContext(CurContext); 4788 CurContext->addDecl(Specialization); 4789 4790 // Syntax is now OK, so return if it has no other effect on semantics. 4791 if (HasNoEffect) { 4792 // Set the template specialization kind. 4793 Specialization->setTemplateSpecializationKind(TSK); 4794 return Specialization; 4795 } 4796 4797 // C++ [temp.explicit]p3: 4798 // A definition of a class template or class member template 4799 // shall be in scope at the point of the explicit instantiation of 4800 // the class template or class member template. 4801 // 4802 // This check comes when we actually try to perform the 4803 // instantiation. 4804 ClassTemplateSpecializationDecl *Def 4805 = cast_or_null<ClassTemplateSpecializationDecl>( 4806 Specialization->getDefinition()); 4807 if (!Def) 4808 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); 4809 else if (TSK == TSK_ExplicitInstantiationDefinition) { 4810 MarkVTableUsed(TemplateNameLoc, Specialization, true); 4811 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation()); 4812 } 4813 4814 // Instantiate the members of this class template specialization. 4815 Def = cast_or_null<ClassTemplateSpecializationDecl>( 4816 Specialization->getDefinition()); 4817 if (Def) { 4818 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind(); 4819 4820 // Fix a TSK_ExplicitInstantiationDeclaration followed by a 4821 // TSK_ExplicitInstantiationDefinition 4822 if (Old_TSK == TSK_ExplicitInstantiationDeclaration && 4823 TSK == TSK_ExplicitInstantiationDefinition) 4824 Def->setTemplateSpecializationKind(TSK); 4825 4826 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); 4827 } 4828 4829 // Set the template specialization kind. 4830 Specialization->setTemplateSpecializationKind(TSK); 4831 return Specialization; 4832} 4833 4834// Explicit instantiation of a member class of a class template. 4835DeclResult 4836Sema::ActOnExplicitInstantiation(Scope *S, 4837 SourceLocation ExternLoc, 4838 SourceLocation TemplateLoc, 4839 unsigned TagSpec, 4840 SourceLocation KWLoc, 4841 CXXScopeSpec &SS, 4842 IdentifierInfo *Name, 4843 SourceLocation NameLoc, 4844 AttributeList *Attr) { 4845 4846 bool Owned = false; 4847 bool IsDependent = false; 4848 Decl *TagD = ActOnTag(S, TagSpec, Sema::TUK_Reference, 4849 KWLoc, SS, Name, NameLoc, Attr, AS_none, 4850 MultiTemplateParamsArg(*this, 0, 0), 4851 Owned, IsDependent); 4852 assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); 4853 4854 if (!TagD) 4855 return true; 4856 4857 TagDecl *Tag = cast<TagDecl>(TagD); 4858 if (Tag->isEnum()) { 4859 Diag(TemplateLoc, diag::err_explicit_instantiation_enum) 4860 << Context.getTypeDeclType(Tag); 4861 return true; 4862 } 4863 4864 if (Tag->isInvalidDecl()) 4865 return true; 4866 4867 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); 4868 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); 4869 if (!Pattern) { 4870 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) 4871 << Context.getTypeDeclType(Record); 4872 Diag(Record->getLocation(), diag::note_nontemplate_decl_here); 4873 return true; 4874 } 4875 4876 // C++0x [temp.explicit]p2: 4877 // If the explicit instantiation is for a class or member class, the 4878 // elaborated-type-specifier in the declaration shall include a 4879 // simple-template-id. 4880 // 4881 // C++98 has the same restriction, just worded differently. 4882 if (!ScopeSpecifierHasTemplateId(SS)) 4883 Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id) 4884 << Record << SS.getRange(); 4885 4886 // C++0x [temp.explicit]p2: 4887 // There are two forms of explicit instantiation: an explicit instantiation 4888 // definition and an explicit instantiation declaration. An explicit 4889 // instantiation declaration begins with the extern keyword. [...] 4890 TemplateSpecializationKind TSK 4891 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4892 : TSK_ExplicitInstantiationDeclaration; 4893 4894 // C++0x [temp.explicit]p2: 4895 // [...] An explicit instantiation shall appear in an enclosing 4896 // namespace of its template. [...] 4897 // 4898 // This is C++ DR 275. 4899 CheckExplicitInstantiationScope(*this, Record, NameLoc, true); 4900 4901 // Verify that it is okay to explicitly instantiate here. 4902 CXXRecordDecl *PrevDecl 4903 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration()); 4904 if (!PrevDecl && Record->getDefinition()) 4905 PrevDecl = Record; 4906 if (PrevDecl) { 4907 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); 4908 bool HasNoEffect = false; 4909 assert(MSInfo && "No member specialization information?"); 4910 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, 4911 PrevDecl, 4912 MSInfo->getTemplateSpecializationKind(), 4913 MSInfo->getPointOfInstantiation(), 4914 HasNoEffect)) 4915 return true; 4916 if (HasNoEffect) 4917 return TagD; 4918 } 4919 4920 CXXRecordDecl *RecordDef 4921 = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4922 if (!RecordDef) { 4923 // C++ [temp.explicit]p3: 4924 // A definition of a member class of a class template shall be in scope 4925 // at the point of an explicit instantiation of the member class. 4926 CXXRecordDecl *Def 4927 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition()); 4928 if (!Def) { 4929 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) 4930 << 0 << Record->getDeclName() << Record->getDeclContext(); 4931 Diag(Pattern->getLocation(), diag::note_forward_declaration) 4932 << Pattern; 4933 return true; 4934 } else { 4935 if (InstantiateClass(NameLoc, Record, Def, 4936 getTemplateInstantiationArgs(Record), 4937 TSK)) 4938 return true; 4939 4940 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4941 if (!RecordDef) 4942 return true; 4943 } 4944 } 4945 4946 // Instantiate all of the members of the class. 4947 InstantiateClassMembers(NameLoc, RecordDef, 4948 getTemplateInstantiationArgs(Record), TSK); 4949 4950 if (TSK == TSK_ExplicitInstantiationDefinition) 4951 MarkVTableUsed(NameLoc, RecordDef, true); 4952 4953 // FIXME: We don't have any representation for explicit instantiations of 4954 // member classes. Such a representation is not needed for compilation, but it 4955 // should be available for clients that want to see all of the declarations in 4956 // the source code. 4957 return TagD; 4958} 4959 4960DeclResult Sema::ActOnExplicitInstantiation(Scope *S, 4961 SourceLocation ExternLoc, 4962 SourceLocation TemplateLoc, 4963 Declarator &D) { 4964 // Explicit instantiations always require a name. 4965 // TODO: check if/when DNInfo should replace Name. 4966 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 4967 DeclarationName Name = NameInfo.getName(); 4968 if (!Name) { 4969 if (!D.isInvalidType()) 4970 Diag(D.getDeclSpec().getSourceRange().getBegin(), 4971 diag::err_explicit_instantiation_requires_name) 4972 << D.getDeclSpec().getSourceRange() 4973 << D.getSourceRange(); 4974 4975 return true; 4976 } 4977 4978 // The scope passed in may not be a decl scope. Zip up the scope tree until 4979 // we find one that is. 4980 while ((S->getFlags() & Scope::DeclScope) == 0 || 4981 (S->getFlags() & Scope::TemplateParamScope) != 0) 4982 S = S->getParent(); 4983 4984 // Determine the type of the declaration. 4985 TypeSourceInfo *T = GetTypeForDeclarator(D, S); 4986 QualType R = T->getType(); 4987 if (R.isNull()) 4988 return true; 4989 4990 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 4991 // Cannot explicitly instantiate a typedef. 4992 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) 4993 << Name; 4994 return true; 4995 } 4996 4997 // C++0x [temp.explicit]p1: 4998 // [...] An explicit instantiation of a function template shall not use the 4999 // inline or constexpr specifiers. 5000 // Presumably, this also applies to member functions of class templates as 5001 // well. 5002 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x) 5003 Diag(D.getDeclSpec().getInlineSpecLoc(), 5004 diag::err_explicit_instantiation_inline) 5005 <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 5006 5007 // FIXME: check for constexpr specifier. 5008 5009 // C++0x [temp.explicit]p2: 5010 // There are two forms of explicit instantiation: an explicit instantiation 5011 // definition and an explicit instantiation declaration. An explicit 5012 // instantiation declaration begins with the extern keyword. [...] 5013 TemplateSpecializationKind TSK 5014 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 5015 : TSK_ExplicitInstantiationDeclaration; 5016 5017 LookupResult Previous(*this, NameInfo, LookupOrdinaryName); 5018 LookupParsedName(Previous, S, &D.getCXXScopeSpec()); 5019 5020 if (!R->isFunctionType()) { 5021 // C++ [temp.explicit]p1: 5022 // A [...] static data member of a class template can be explicitly 5023 // instantiated from the member definition associated with its class 5024 // template. 5025 if (Previous.isAmbiguous()) 5026 return true; 5027 5028 VarDecl *Prev = Previous.getAsSingle<VarDecl>(); 5029 if (!Prev || !Prev->isStaticDataMember()) { 5030 // We expect to see a data data member here. 5031 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) 5032 << Name; 5033 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 5034 P != PEnd; ++P) 5035 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); 5036 return true; 5037 } 5038 5039 if (!Prev->getInstantiatedFromStaticDataMember()) { 5040 // FIXME: Check for explicit specialization? 5041 Diag(D.getIdentifierLoc(), 5042 diag::err_explicit_instantiation_data_member_not_instantiated) 5043 << Prev; 5044 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); 5045 // FIXME: Can we provide a note showing where this was declared? 5046 return true; 5047 } 5048 5049 // C++0x [temp.explicit]p2: 5050 // If the explicit instantiation is for a member function, a member class 5051 // or a static data member of a class template specialization, the name of 5052 // the class template specialization in the qualified-id for the member 5053 // name shall be a simple-template-id. 5054 // 5055 // C++98 has the same restriction, just worded differently. 5056 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5057 Diag(D.getIdentifierLoc(), 5058 diag::ext_explicit_instantiation_without_qualified_id) 5059 << Prev << D.getCXXScopeSpec().getRange(); 5060 5061 // Check the scope of this explicit instantiation. 5062 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); 5063 5064 // Verify that it is okay to explicitly instantiate here. 5065 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); 5066 assert(MSInfo && "Missing static data member specialization info?"); 5067 bool HasNoEffect = false; 5068 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, 5069 MSInfo->getTemplateSpecializationKind(), 5070 MSInfo->getPointOfInstantiation(), 5071 HasNoEffect)) 5072 return true; 5073 if (HasNoEffect) 5074 return (Decl*) 0; 5075 5076 // Instantiate static data member. 5077 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5078 if (TSK == TSK_ExplicitInstantiationDefinition) 5079 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev); 5080 5081 // FIXME: Create an ExplicitInstantiation node? 5082 return (Decl*) 0; 5083 } 5084 5085 // If the declarator is a template-id, translate the parser's template 5086 // argument list into our AST format. 5087 bool HasExplicitTemplateArgs = false; 5088 TemplateArgumentListInfo TemplateArgs; 5089 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 5090 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 5091 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 5092 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 5093 ASTTemplateArgsPtr TemplateArgsPtr(*this, 5094 TemplateId->getTemplateArgs(), 5095 TemplateId->NumArgs); 5096 translateTemplateArguments(TemplateArgsPtr, TemplateArgs); 5097 HasExplicitTemplateArgs = true; 5098 TemplateArgsPtr.release(); 5099 } 5100 5101 // C++ [temp.explicit]p1: 5102 // A [...] function [...] can be explicitly instantiated from its template. 5103 // A member function [...] of a class template can be explicitly 5104 // instantiated from the member definition associated with its class 5105 // template. 5106 UnresolvedSet<8> Matches; 5107 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 5108 P != PEnd; ++P) { 5109 NamedDecl *Prev = *P; 5110 if (!HasExplicitTemplateArgs) { 5111 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { 5112 if (Context.hasSameUnqualifiedType(Method->getType(), R)) { 5113 Matches.clear(); 5114 5115 Matches.addDecl(Method, P.getAccess()); 5116 if (Method->getTemplateSpecializationKind() == TSK_Undeclared) 5117 break; 5118 } 5119 } 5120 } 5121 5122 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); 5123 if (!FunTmpl) 5124 continue; 5125 5126 TemplateDeductionInfo Info(Context, D.getIdentifierLoc()); 5127 FunctionDecl *Specialization = 0; 5128 if (TemplateDeductionResult TDK 5129 = DeduceTemplateArguments(FunTmpl, 5130 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 5131 R, Specialization, Info)) { 5132 // FIXME: Keep track of almost-matches? 5133 (void)TDK; 5134 continue; 5135 } 5136 5137 Matches.addDecl(Specialization, P.getAccess()); 5138 } 5139 5140 // Find the most specialized function template specialization. 5141 UnresolvedSetIterator Result 5142 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, 5143 D.getIdentifierLoc(), 5144 PDiag(diag::err_explicit_instantiation_not_known) << Name, 5145 PDiag(diag::err_explicit_instantiation_ambiguous) << Name, 5146 PDiag(diag::note_explicit_instantiation_candidate)); 5147 5148 if (Result == Matches.end()) 5149 return true; 5150 5151 // Ignore access control bits, we don't need them for redeclaration checking. 5152 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 5153 5154 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { 5155 Diag(D.getIdentifierLoc(), 5156 diag::err_explicit_instantiation_member_function_not_instantiated) 5157 << Specialization 5158 << (Specialization->getTemplateSpecializationKind() == 5159 TSK_ExplicitSpecialization); 5160 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); 5161 return true; 5162 } 5163 5164 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration(); 5165 if (!PrevDecl && Specialization->isThisDeclarationADefinition()) 5166 PrevDecl = Specialization; 5167 5168 if (PrevDecl) { 5169 bool HasNoEffect = false; 5170 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, 5171 PrevDecl, 5172 PrevDecl->getTemplateSpecializationKind(), 5173 PrevDecl->getPointOfInstantiation(), 5174 HasNoEffect)) 5175 return true; 5176 5177 // FIXME: We may still want to build some representation of this 5178 // explicit specialization. 5179 if (HasNoEffect) 5180 return (Decl*) 0; 5181 } 5182 5183 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5184 5185 if (TSK == TSK_ExplicitInstantiationDefinition) 5186 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization); 5187 5188 // C++0x [temp.explicit]p2: 5189 // If the explicit instantiation is for a member function, a member class 5190 // or a static data member of a class template specialization, the name of 5191 // the class template specialization in the qualified-id for the member 5192 // name shall be a simple-template-id. 5193 // 5194 // C++98 has the same restriction, just worded differently. 5195 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); 5196 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && 5197 D.getCXXScopeSpec().isSet() && 5198 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5199 Diag(D.getIdentifierLoc(), 5200 diag::ext_explicit_instantiation_without_qualified_id) 5201 << Specialization << D.getCXXScopeSpec().getRange(); 5202 5203 CheckExplicitInstantiationScope(*this, 5204 FunTmpl? (NamedDecl *)FunTmpl 5205 : Specialization->getInstantiatedFromMemberFunction(), 5206 D.getIdentifierLoc(), 5207 D.getCXXScopeSpec().isSet()); 5208 5209 // FIXME: Create some kind of ExplicitInstantiationDecl here. 5210 return (Decl*) 0; 5211} 5212 5213TypeResult 5214Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5215 const CXXScopeSpec &SS, IdentifierInfo *Name, 5216 SourceLocation TagLoc, SourceLocation NameLoc) { 5217 // This has to hold, because SS is expected to be defined. 5218 assert(Name && "Expected a name in a dependent tag"); 5219 5220 NestedNameSpecifier *NNS 5221 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5222 if (!NNS) 5223 return true; 5224 5225 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5226 5227 if (TUK == TUK_Declaration || TUK == TUK_Definition) { 5228 Diag(NameLoc, diag::err_dependent_tag_decl) 5229 << (TUK == TUK_Definition) << Kind << SS.getRange(); 5230 return true; 5231 } 5232 5233 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind); 5234 return ParsedType::make(Context.getDependentNameType(Kwd, NNS, Name)); 5235} 5236 5237TypeResult 5238Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, 5239 const CXXScopeSpec &SS, const IdentifierInfo &II, 5240 SourceLocation IdLoc) { 5241 NestedNameSpecifier *NNS 5242 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5243 if (!NNS) 5244 return true; 5245 5246 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() && 5247 !getLangOptions().CPlusPlus0x) 5248 Diag(TypenameLoc, diag::ext_typename_outside_of_template) 5249 << FixItHint::CreateRemoval(TypenameLoc); 5250 5251 QualType T = CheckTypenameType(ETK_Typename, NNS, II, 5252 TypenameLoc, SS.getRange(), IdLoc); 5253 if (T.isNull()) 5254 return true; 5255 5256 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); 5257 if (isa<DependentNameType>(T)) { 5258 DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc()); 5259 TL.setKeywordLoc(TypenameLoc); 5260 TL.setQualifierRange(SS.getRange()); 5261 TL.setNameLoc(IdLoc); 5262 } else { 5263 ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc()); 5264 TL.setKeywordLoc(TypenameLoc); 5265 TL.setQualifierRange(SS.getRange()); 5266 cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc); 5267 } 5268 5269 return CreateParsedType(T, TSI); 5270} 5271 5272TypeResult 5273Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, 5274 const CXXScopeSpec &SS, SourceLocation TemplateLoc, 5275 ParsedType Ty) { 5276 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() && 5277 !getLangOptions().CPlusPlus0x) 5278 Diag(TypenameLoc, diag::ext_typename_outside_of_template) 5279 << FixItHint::CreateRemoval(TypenameLoc); 5280 5281 TypeSourceInfo *InnerTSI = 0; 5282 QualType T = GetTypeFromParser(Ty, &InnerTSI); 5283 5284 assert(isa<TemplateSpecializationType>(T) && 5285 "Expected a template specialization type"); 5286 5287 if (computeDeclContext(SS, false)) { 5288 // If we can compute a declaration context, then the "typename" 5289 // keyword was superfluous. Just build an ElaboratedType to keep 5290 // track of the nested-name-specifier. 5291 5292 // Push the inner type, preserving its source locations if possible. 5293 TypeLocBuilder Builder; 5294 if (InnerTSI) 5295 Builder.pushFullCopy(InnerTSI->getTypeLoc()); 5296 else 5297 Builder.push<TemplateSpecializationTypeLoc>(T).initialize(TemplateLoc); 5298 5299 /* Note: NNS already embedded in template specialization type T. */ 5300 T = Context.getElaboratedType(ETK_Typename, /*NNS=*/0, T); 5301 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T); 5302 TL.setKeywordLoc(TypenameLoc); 5303 TL.setQualifierRange(SS.getRange()); 5304 5305 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T); 5306 return CreateParsedType(T, TSI); 5307 } 5308 5309 // TODO: it's really silly that we make a template specialization 5310 // type earlier only to drop it again here. 5311 TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T); 5312 DependentTemplateName *DTN = 5313 TST->getTemplateName().getAsDependentTemplateName(); 5314 assert(DTN && "dependent template has non-dependent name?"); 5315 assert(DTN->getQualifier() 5316 == static_cast<NestedNameSpecifier*>(SS.getScopeRep())); 5317 T = Context.getDependentTemplateSpecializationType(ETK_Typename, 5318 DTN->getQualifier(), 5319 DTN->getIdentifier(), 5320 TST->getNumArgs(), 5321 TST->getArgs()); 5322 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); 5323 DependentTemplateSpecializationTypeLoc TL = 5324 cast<DependentTemplateSpecializationTypeLoc>(TSI->getTypeLoc()); 5325 if (InnerTSI) { 5326 TemplateSpecializationTypeLoc TSTL = 5327 cast<TemplateSpecializationTypeLoc>(InnerTSI->getTypeLoc()); 5328 TL.setLAngleLoc(TSTL.getLAngleLoc()); 5329 TL.setRAngleLoc(TSTL.getRAngleLoc()); 5330 for (unsigned I = 0, E = TST->getNumArgs(); I != E; ++I) 5331 TL.setArgLocInfo(I, TSTL.getArgLocInfo(I)); 5332 } else { 5333 TL.initializeLocal(SourceLocation()); 5334 } 5335 TL.setKeywordLoc(TypenameLoc); 5336 TL.setQualifierRange(SS.getRange()); 5337 return CreateParsedType(T, TSI); 5338} 5339 5340/// \brief Build the type that describes a C++ typename specifier, 5341/// e.g., "typename T::type". 5342QualType 5343Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword, 5344 NestedNameSpecifier *NNS, const IdentifierInfo &II, 5345 SourceLocation KeywordLoc, SourceRange NNSRange, 5346 SourceLocation IILoc) { 5347 CXXScopeSpec SS; 5348 SS.setScopeRep(NNS); 5349 SS.setRange(NNSRange); 5350 5351 DeclContext *Ctx = computeDeclContext(SS); 5352 if (!Ctx) { 5353 // If the nested-name-specifier is dependent and couldn't be 5354 // resolved to a type, build a typename type. 5355 assert(NNS->isDependent()); 5356 return Context.getDependentNameType(Keyword, NNS, &II); 5357 } 5358 5359 // If the nested-name-specifier refers to the current instantiation, 5360 // the "typename" keyword itself is superfluous. In C++03, the 5361 // program is actually ill-formed. However, DR 382 (in C++0x CD1) 5362 // allows such extraneous "typename" keywords, and we retroactively 5363 // apply this DR to C++03 code with only a warning. In any case we continue. 5364 5365 if (RequireCompleteDeclContext(SS, Ctx)) 5366 return QualType(); 5367 5368 DeclarationName Name(&II); 5369 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName); 5370 LookupQualifiedName(Result, Ctx); 5371 unsigned DiagID = 0; 5372 Decl *Referenced = 0; 5373 switch (Result.getResultKind()) { 5374 case LookupResult::NotFound: 5375 DiagID = diag::err_typename_nested_not_found; 5376 break; 5377 5378 case LookupResult::NotFoundInCurrentInstantiation: 5379 // Okay, it's a member of an unknown instantiation. 5380 return Context.getDependentNameType(Keyword, NNS, &II); 5381 5382 case LookupResult::Found: 5383 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { 5384 // We found a type. Build an ElaboratedType, since the 5385 // typename-specifier was just sugar. 5386 return Context.getElaboratedType(ETK_Typename, NNS, 5387 Context.getTypeDeclType(Type)); 5388 } 5389 5390 DiagID = diag::err_typename_nested_not_type; 5391 Referenced = Result.getFoundDecl(); 5392 break; 5393 5394 case LookupResult::FoundUnresolvedValue: 5395 llvm_unreachable("unresolved using decl in non-dependent context"); 5396 return QualType(); 5397 5398 case LookupResult::FoundOverloaded: 5399 DiagID = diag::err_typename_nested_not_type; 5400 Referenced = *Result.begin(); 5401 break; 5402 5403 case LookupResult::Ambiguous: 5404 return QualType(); 5405 } 5406 5407 // If we get here, it's because name lookup did not find a 5408 // type. Emit an appropriate diagnostic and return an error. 5409 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(), 5410 IILoc); 5411 Diag(IILoc, DiagID) << FullRange << Name << Ctx; 5412 if (Referenced) 5413 Diag(Referenced->getLocation(), diag::note_typename_refers_here) 5414 << Name; 5415 return QualType(); 5416} 5417 5418namespace { 5419 // See Sema::RebuildTypeInCurrentInstantiation 5420 class CurrentInstantiationRebuilder 5421 : public TreeTransform<CurrentInstantiationRebuilder> { 5422 SourceLocation Loc; 5423 DeclarationName Entity; 5424 5425 public: 5426 typedef TreeTransform<CurrentInstantiationRebuilder> inherited; 5427 5428 CurrentInstantiationRebuilder(Sema &SemaRef, 5429 SourceLocation Loc, 5430 DeclarationName Entity) 5431 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), 5432 Loc(Loc), Entity(Entity) { } 5433 5434 /// \brief Determine whether the given type \p T has already been 5435 /// transformed. 5436 /// 5437 /// For the purposes of type reconstruction, a type has already been 5438 /// transformed if it is NULL or if it is not dependent. 5439 bool AlreadyTransformed(QualType T) { 5440 return T.isNull() || !T->isDependentType(); 5441 } 5442 5443 /// \brief Returns the location of the entity whose type is being 5444 /// rebuilt. 5445 SourceLocation getBaseLocation() { return Loc; } 5446 5447 /// \brief Returns the name of the entity whose type is being rebuilt. 5448 DeclarationName getBaseEntity() { return Entity; } 5449 5450 /// \brief Sets the "base" location and entity when that 5451 /// information is known based on another transformation. 5452 void setBase(SourceLocation Loc, DeclarationName Entity) { 5453 this->Loc = Loc; 5454 this->Entity = Entity; 5455 } 5456 }; 5457} 5458 5459/// \brief Rebuilds a type within the context of the current instantiation. 5460/// 5461/// The type \p T is part of the type of an out-of-line member definition of 5462/// a class template (or class template partial specialization) that was parsed 5463/// and constructed before we entered the scope of the class template (or 5464/// partial specialization thereof). This routine will rebuild that type now 5465/// that we have entered the declarator's scope, which may produce different 5466/// canonical types, e.g., 5467/// 5468/// \code 5469/// template<typename T> 5470/// struct X { 5471/// typedef T* pointer; 5472/// pointer data(); 5473/// }; 5474/// 5475/// template<typename T> 5476/// typename X<T>::pointer X<T>::data() { ... } 5477/// \endcode 5478/// 5479/// Here, the type "typename X<T>::pointer" will be created as a DependentNameType, 5480/// since we do not know that we can look into X<T> when we parsed the type. 5481/// This function will rebuild the type, performing the lookup of "pointer" 5482/// in X<T> and returning an ElaboratedType whose canonical type is the same 5483/// as the canonical type of T*, allowing the return types of the out-of-line 5484/// definition and the declaration to match. 5485TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T, 5486 SourceLocation Loc, 5487 DeclarationName Name) { 5488 if (!T || !T->getType()->isDependentType()) 5489 return T; 5490 5491 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); 5492 return Rebuilder.TransformType(T); 5493} 5494 5495ExprResult Sema::RebuildExprInCurrentInstantiation(Expr *E) { 5496 CurrentInstantiationRebuilder Rebuilder(*this, E->getExprLoc(), 5497 DeclarationName()); 5498 return Rebuilder.TransformExpr(E); 5499} 5500 5501bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) { 5502 if (SS.isInvalid()) return true; 5503 5504 NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5505 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(), 5506 DeclarationName()); 5507 NestedNameSpecifier *Rebuilt = 5508 Rebuilder.TransformNestedNameSpecifier(NNS, SS.getRange()); 5509 if (!Rebuilt) return true; 5510 5511 SS.setScopeRep(Rebuilt); 5512 return false; 5513} 5514 5515/// \brief Produces a formatted string that describes the binding of 5516/// template parameters to template arguments. 5517std::string 5518Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5519 const TemplateArgumentList &Args) { 5520 // FIXME: For variadic templates, we'll need to get the structured list. 5521 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(), 5522 Args.flat_size()); 5523} 5524 5525std::string 5526Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5527 const TemplateArgument *Args, 5528 unsigned NumArgs) { 5529 std::string Result; 5530 5531 if (!Params || Params->size() == 0 || NumArgs == 0) 5532 return Result; 5533 5534 for (unsigned I = 0, N = Params->size(); I != N; ++I) { 5535 if (I >= NumArgs) 5536 break; 5537 5538 if (I == 0) 5539 Result += "[with "; 5540 else 5541 Result += ", "; 5542 5543 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { 5544 Result += Id->getName(); 5545 } else { 5546 Result += '$'; 5547 Result += llvm::utostr(I); 5548 } 5549 5550 Result += " = "; 5551 5552 switch (Args[I].getKind()) { 5553 case TemplateArgument::Null: 5554 Result += "<no value>"; 5555 break; 5556 5557 case TemplateArgument::Type: { 5558 std::string TypeStr; 5559 Args[I].getAsType().getAsStringInternal(TypeStr, 5560 Context.PrintingPolicy); 5561 Result += TypeStr; 5562 break; 5563 } 5564 5565 case TemplateArgument::Declaration: { 5566 bool Unnamed = true; 5567 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) { 5568 if (ND->getDeclName()) { 5569 Unnamed = false; 5570 Result += ND->getNameAsString(); 5571 } 5572 } 5573 5574 if (Unnamed) { 5575 Result += "<anonymous>"; 5576 } 5577 break; 5578 } 5579 5580 case TemplateArgument::Template: { 5581 std::string Str; 5582 llvm::raw_string_ostream OS(Str); 5583 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy); 5584 Result += OS.str(); 5585 break; 5586 } 5587 5588 case TemplateArgument::Integral: { 5589 Result += Args[I].getAsIntegral()->toString(10); 5590 break; 5591 } 5592 5593 case TemplateArgument::Expression: { 5594 // FIXME: This is non-optimal, since we're regurgitating the 5595 // expression we were given. 5596 std::string Str; 5597 { 5598 llvm::raw_string_ostream OS(Str); 5599 Args[I].getAsExpr()->printPretty(OS, Context, 0, 5600 Context.PrintingPolicy); 5601 } 5602 Result += Str; 5603 break; 5604 } 5605 5606 case TemplateArgument::Pack: 5607 // FIXME: Format template argument packs 5608 Result += "<template argument pack>"; 5609 break; 5610 } 5611 } 5612 5613 Result += ']'; 5614 return Result; 5615} 5616