SemaTemplate.cpp revision 210299
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 "Sema.h" 13#include "Lookup.h" 14#include "TreeTransform.h" 15#include "clang/AST/ASTContext.h" 16#include "clang/AST/Expr.h" 17#include "clang/AST/ExprCXX.h" 18#include "clang/AST/DeclFriend.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Parse/Template.h" 22#include "clang/Basic/LangOptions.h" 23#include "clang/Basic/PartialDiagnostic.h" 24#include "llvm/ADT/StringExtras.h" 25using namespace clang; 26 27/// \brief Determine whether the declaration found is acceptable as the name 28/// of a template and, if so, return that template declaration. Otherwise, 29/// returns NULL. 30static NamedDecl *isAcceptableTemplateName(ASTContext &Context, 31 NamedDecl *Orig) { 32 NamedDecl *D = Orig->getUnderlyingDecl(); 33 34 if (isa<TemplateDecl>(D)) 35 return Orig; 36 37 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) { 38 // C++ [temp.local]p1: 39 // Like normal (non-template) classes, class templates have an 40 // injected-class-name (Clause 9). The injected-class-name 41 // can be used with or without a template-argument-list. When 42 // it is used without a template-argument-list, it is 43 // equivalent to the injected-class-name followed by the 44 // template-parameters of the class template enclosed in 45 // <>. When it is used with a template-argument-list, it 46 // refers to the specified class template specialization, 47 // which could be the current specialization or another 48 // specialization. 49 if (Record->isInjectedClassName()) { 50 Record = cast<CXXRecordDecl>(Record->getDeclContext()); 51 if (Record->getDescribedClassTemplate()) 52 return Record->getDescribedClassTemplate(); 53 54 if (ClassTemplateSpecializationDecl *Spec 55 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) 56 return Spec->getSpecializedTemplate(); 57 } 58 59 return 0; 60 } 61 62 return 0; 63} 64 65static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) { 66 // The set of class templates we've already seen. 67 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates; 68 LookupResult::Filter filter = R.makeFilter(); 69 while (filter.hasNext()) { 70 NamedDecl *Orig = filter.next(); 71 NamedDecl *Repl = isAcceptableTemplateName(C, Orig); 72 if (!Repl) 73 filter.erase(); 74 else if (Repl != Orig) { 75 76 // C++ [temp.local]p3: 77 // A lookup that finds an injected-class-name (10.2) can result in an 78 // ambiguity in certain cases (for example, if it is found in more than 79 // one base class). If all of the injected-class-names that are found 80 // refer to specializations of the same class template, and if the name 81 // is followed by a template-argument-list, the reference refers to the 82 // class template itself and not a specialization thereof, and is not 83 // ambiguous. 84 // 85 // FIXME: Will we eventually have to do the same for alias templates? 86 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl)) 87 if (!ClassTemplates.insert(ClassTmpl)) { 88 filter.erase(); 89 continue; 90 } 91 92 filter.replace(Repl); 93 } 94 } 95 filter.done(); 96} 97 98TemplateNameKind Sema::isTemplateName(Scope *S, 99 CXXScopeSpec &SS, 100 UnqualifiedId &Name, 101 TypeTy *ObjectTypePtr, 102 bool EnteringContext, 103 TemplateTy &TemplateResult, 104 bool &MemberOfUnknownSpecialization) { 105 assert(getLangOptions().CPlusPlus && "No template names in C!"); 106 107 DeclarationName TName; 108 MemberOfUnknownSpecialization = false; 109 110 switch (Name.getKind()) { 111 case UnqualifiedId::IK_Identifier: 112 TName = DeclarationName(Name.Identifier); 113 break; 114 115 case UnqualifiedId::IK_OperatorFunctionId: 116 TName = Context.DeclarationNames.getCXXOperatorName( 117 Name.OperatorFunctionId.Operator); 118 break; 119 120 case UnqualifiedId::IK_LiteralOperatorId: 121 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier); 122 break; 123 124 default: 125 return TNK_Non_template; 126 } 127 128 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 129 130 LookupResult R(*this, TName, Name.getSourceRange().getBegin(), 131 LookupOrdinaryName); 132 R.suppressDiagnostics(); 133 LookupTemplateName(R, S, SS, ObjectType, EnteringContext, 134 MemberOfUnknownSpecialization); 135 if (R.empty() || R.isAmbiguous()) 136 return TNK_Non_template; 137 138 TemplateName Template; 139 TemplateNameKind TemplateKind; 140 141 unsigned ResultCount = R.end() - R.begin(); 142 if (ResultCount > 1) { 143 // We assume that we'll preserve the qualifier from a function 144 // template name in other ways. 145 Template = Context.getOverloadedTemplateName(R.begin(), R.end()); 146 TemplateKind = TNK_Function_template; 147 } else { 148 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl()); 149 150 if (SS.isSet() && !SS.isInvalid()) { 151 NestedNameSpecifier *Qualifier 152 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 153 Template = Context.getQualifiedTemplateName(Qualifier, false, TD); 154 } else { 155 Template = TemplateName(TD); 156 } 157 158 if (isa<FunctionTemplateDecl>(TD)) 159 TemplateKind = TNK_Function_template; 160 else { 161 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD)); 162 TemplateKind = TNK_Type_template; 163 } 164 } 165 166 TemplateResult = TemplateTy::make(Template); 167 return TemplateKind; 168} 169 170bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II, 171 SourceLocation IILoc, 172 Scope *S, 173 const CXXScopeSpec *SS, 174 TemplateTy &SuggestedTemplate, 175 TemplateNameKind &SuggestedKind) { 176 // We can't recover unless there's a dependent scope specifier preceding the 177 // template name. 178 // FIXME: Typo correction? 179 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) || 180 computeDeclContext(*SS)) 181 return false; 182 183 // The code is missing a 'template' keyword prior to the dependent template 184 // name. 185 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep(); 186 Diag(IILoc, diag::err_template_kw_missing) 187 << Qualifier << II.getName() 188 << FixItHint::CreateInsertion(IILoc, "template "); 189 SuggestedTemplate 190 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II)); 191 SuggestedKind = TNK_Dependent_template_name; 192 return true; 193} 194 195void Sema::LookupTemplateName(LookupResult &Found, 196 Scope *S, CXXScopeSpec &SS, 197 QualType ObjectType, 198 bool EnteringContext, 199 bool &MemberOfUnknownSpecialization) { 200 // Determine where to perform name lookup 201 MemberOfUnknownSpecialization = false; 202 DeclContext *LookupCtx = 0; 203 bool isDependent = false; 204 if (!ObjectType.isNull()) { 205 // This nested-name-specifier occurs in a member access expression, e.g., 206 // x->B::f, and we are looking into the type of the object. 207 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 208 LookupCtx = computeDeclContext(ObjectType); 209 isDependent = ObjectType->isDependentType(); 210 assert((isDependent || !ObjectType->isIncompleteType()) && 211 "Caller should have completed object type"); 212 } else if (SS.isSet()) { 213 // This nested-name-specifier occurs after another nested-name-specifier, 214 // so long into the context associated with the prior nested-name-specifier. 215 LookupCtx = computeDeclContext(SS, EnteringContext); 216 isDependent = isDependentScopeSpecifier(SS); 217 218 // The declaration context must be complete. 219 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx)) 220 return; 221 } 222 223 bool ObjectTypeSearchedInScope = false; 224 if (LookupCtx) { 225 // Perform "qualified" name lookup into the declaration context we 226 // computed, which is either the type of the base of a member access 227 // expression or the declaration context associated with a prior 228 // nested-name-specifier. 229 LookupQualifiedName(Found, LookupCtx); 230 231 if (!ObjectType.isNull() && Found.empty()) { 232 // C++ [basic.lookup.classref]p1: 233 // In a class member access expression (5.2.5), if the . or -> token is 234 // immediately followed by an identifier followed by a <, the 235 // identifier must be looked up to determine whether the < is the 236 // beginning of a template argument list (14.2) or a less-than operator. 237 // The identifier is first looked up in the class of the object 238 // expression. If the identifier is not found, it is then looked up in 239 // the context of the entire postfix-expression and shall name a class 240 // or function template. 241 // 242 // FIXME: When we're instantiating a template, do we actually have to 243 // look in the scope of the template? Seems fishy... 244 if (S) LookupName(Found, S); 245 ObjectTypeSearchedInScope = true; 246 } 247 } else if (isDependent) { 248 // We cannot look into a dependent object type or nested nme 249 // specifier. 250 MemberOfUnknownSpecialization = true; 251 return; 252 } else { 253 // Perform unqualified name lookup in the current scope. 254 LookupName(Found, S); 255 } 256 257 if (Found.empty() && !isDependent) { 258 // If we did not find any names, attempt to correct any typos. 259 DeclarationName Name = Found.getLookupName(); 260 if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx, 261 false, CTC_CXXCasts)) { 262 FilterAcceptableTemplateNames(Context, Found); 263 if (!Found.empty()) { 264 if (LookupCtx) 265 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest) 266 << Name << LookupCtx << Found.getLookupName() << SS.getRange() 267 << FixItHint::CreateReplacement(Found.getNameLoc(), 268 Found.getLookupName().getAsString()); 269 else 270 Diag(Found.getNameLoc(), diag::err_no_template_suggest) 271 << Name << Found.getLookupName() 272 << FixItHint::CreateReplacement(Found.getNameLoc(), 273 Found.getLookupName().getAsString()); 274 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>()) 275 Diag(Template->getLocation(), diag::note_previous_decl) 276 << Template->getDeclName(); 277 } 278 } else { 279 Found.clear(); 280 Found.setLookupName(Name); 281 } 282 } 283 284 FilterAcceptableTemplateNames(Context, Found); 285 if (Found.empty()) 286 return; 287 288 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) { 289 // C++ [basic.lookup.classref]p1: 290 // [...] If the lookup in the class of the object expression finds a 291 // template, the name is also looked up in the context of the entire 292 // postfix-expression and [...] 293 // 294 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(), 295 LookupOrdinaryName); 296 LookupName(FoundOuter, S); 297 FilterAcceptableTemplateNames(Context, FoundOuter); 298 299 if (FoundOuter.empty()) { 300 // - if the name is not found, the name found in the class of the 301 // object expression is used, otherwise 302 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) { 303 // - if the name is found in the context of the entire 304 // postfix-expression and does not name a class template, the name 305 // found in the class of the object expression is used, otherwise 306 } else if (!Found.isSuppressingDiagnostics()) { 307 // - if the name found is a class template, it must refer to the same 308 // entity as the one found in the class of the object expression, 309 // otherwise the program is ill-formed. 310 if (!Found.isSingleResult() || 311 Found.getFoundDecl()->getCanonicalDecl() 312 != FoundOuter.getFoundDecl()->getCanonicalDecl()) { 313 Diag(Found.getNameLoc(), 314 diag::ext_nested_name_member_ref_lookup_ambiguous) 315 << Found.getLookupName() 316 << ObjectType; 317 Diag(Found.getRepresentativeDecl()->getLocation(), 318 diag::note_ambig_member_ref_object_type) 319 << ObjectType; 320 Diag(FoundOuter.getFoundDecl()->getLocation(), 321 diag::note_ambig_member_ref_scope); 322 323 // Recover by taking the template that we found in the object 324 // expression's type. 325 } 326 } 327 } 328} 329 330/// ActOnDependentIdExpression - Handle a dependent id-expression that 331/// was just parsed. This is only possible with an explicit scope 332/// specifier naming a dependent type. 333Sema::OwningExprResult 334Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS, 335 DeclarationName Name, 336 SourceLocation NameLoc, 337 bool isAddressOfOperand, 338 const TemplateArgumentListInfo *TemplateArgs) { 339 NestedNameSpecifier *Qualifier 340 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 341 342 DeclContext *DC = getFunctionLevelDeclContext(); 343 344 if (!isAddressOfOperand && 345 isa<CXXMethodDecl>(DC) && 346 cast<CXXMethodDecl>(DC)->isInstance()) { 347 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); 348 349 // Since the 'this' expression is synthesized, we don't need to 350 // perform the double-lookup check. 351 NamedDecl *FirstQualifierInScope = 0; 352 353 return Owned(CXXDependentScopeMemberExpr::Create(Context, 354 /*This*/ 0, ThisType, 355 /*IsArrow*/ true, 356 /*Op*/ SourceLocation(), 357 Qualifier, SS.getRange(), 358 FirstQualifierInScope, 359 Name, NameLoc, 360 TemplateArgs)); 361 } 362 363 return BuildDependentDeclRefExpr(SS, Name, NameLoc, TemplateArgs); 364} 365 366Sema::OwningExprResult 367Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS, 368 DeclarationName Name, 369 SourceLocation NameLoc, 370 const TemplateArgumentListInfo *TemplateArgs) { 371 return Owned(DependentScopeDeclRefExpr::Create(Context, 372 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 373 SS.getRange(), 374 Name, NameLoc, 375 TemplateArgs)); 376} 377 378/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining 379/// that the template parameter 'PrevDecl' is being shadowed by a new 380/// declaration at location Loc. Returns true to indicate that this is 381/// an error, and false otherwise. 382bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { 383 assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); 384 385 // Microsoft Visual C++ permits template parameters to be shadowed. 386 if (getLangOptions().Microsoft) 387 return false; 388 389 // C++ [temp.local]p4: 390 // A template-parameter shall not be redeclared within its 391 // scope (including nested scopes). 392 Diag(Loc, diag::err_template_param_shadow) 393 << cast<NamedDecl>(PrevDecl)->getDeclName(); 394 Diag(PrevDecl->getLocation(), diag::note_template_param_here); 395 return true; 396} 397 398/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset 399/// the parameter D to reference the templated declaration and return a pointer 400/// to the template declaration. Otherwise, do nothing to D and return null. 401TemplateDecl *Sema::AdjustDeclIfTemplate(DeclPtrTy &D) { 402 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D.getAs<Decl>())) { 403 D = DeclPtrTy::make(Temp->getTemplatedDecl()); 404 return Temp; 405 } 406 return 0; 407} 408 409static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, 410 const ParsedTemplateArgument &Arg) { 411 412 switch (Arg.getKind()) { 413 case ParsedTemplateArgument::Type: { 414 TypeSourceInfo *DI; 415 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); 416 if (!DI) 417 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation()); 418 return TemplateArgumentLoc(TemplateArgument(T), DI); 419 } 420 421 case ParsedTemplateArgument::NonType: { 422 Expr *E = static_cast<Expr *>(Arg.getAsExpr()); 423 return TemplateArgumentLoc(TemplateArgument(E), E); 424 } 425 426 case ParsedTemplateArgument::Template: { 427 TemplateName Template 428 = TemplateName::getFromVoidPointer(Arg.getAsTemplate().get()); 429 return TemplateArgumentLoc(TemplateArgument(Template), 430 Arg.getScopeSpec().getRange(), 431 Arg.getLocation()); 432 } 433 } 434 435 llvm_unreachable("Unhandled parsed template argument"); 436 return TemplateArgumentLoc(); 437} 438 439/// \brief Translates template arguments as provided by the parser 440/// into template arguments used by semantic analysis. 441void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn, 442 TemplateArgumentListInfo &TemplateArgs) { 443 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) 444 TemplateArgs.addArgument(translateTemplateArgument(*this, 445 TemplateArgsIn[I])); 446} 447 448/// ActOnTypeParameter - Called when a C++ template type parameter 449/// (e.g., "typename T") has been parsed. Typename specifies whether 450/// the keyword "typename" was used to declare the type parameter 451/// (otherwise, "class" was used), and KeyLoc is the location of the 452/// "class" or "typename" keyword. ParamName is the name of the 453/// parameter (NULL indicates an unnamed template parameter) and 454/// ParamName is the location of the parameter name (if any). 455/// If the type parameter has a default argument, it will be added 456/// later via ActOnTypeParameterDefault. 457Sema::DeclPtrTy Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, 458 SourceLocation EllipsisLoc, 459 SourceLocation KeyLoc, 460 IdentifierInfo *ParamName, 461 SourceLocation ParamNameLoc, 462 unsigned Depth, unsigned Position, 463 SourceLocation EqualLoc, 464 TypeTy *DefaultArg) { 465 assert(S->isTemplateParamScope() && 466 "Template type parameter not in template parameter scope!"); 467 bool Invalid = false; 468 469 if (ParamName) { 470 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc, 471 LookupOrdinaryName, 472 ForRedeclaration); 473 if (PrevDecl && PrevDecl->isTemplateParameter()) 474 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc, 475 PrevDecl); 476 } 477 478 SourceLocation Loc = ParamNameLoc; 479 if (!ParamName) 480 Loc = KeyLoc; 481 482 TemplateTypeParmDecl *Param 483 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(), 484 Loc, Depth, Position, ParamName, Typename, 485 Ellipsis); 486 if (Invalid) 487 Param->setInvalidDecl(); 488 489 if (ParamName) { 490 // Add the template parameter into the current scope. 491 S->AddDecl(DeclPtrTy::make(Param)); 492 IdResolver.AddDecl(Param); 493 } 494 495 // Handle the default argument, if provided. 496 if (DefaultArg) { 497 TypeSourceInfo *DefaultTInfo; 498 GetTypeFromParser(DefaultArg, &DefaultTInfo); 499 500 assert(DefaultTInfo && "expected source information for type"); 501 502 // C++0x [temp.param]p9: 503 // A default template-argument may be specified for any kind of 504 // template-parameter that is not a template parameter pack. 505 if (Ellipsis) { 506 Diag(EqualLoc, diag::err_template_param_pack_default_arg); 507 return DeclPtrTy::make(Param); 508 } 509 510 // Check the template argument itself. 511 if (CheckTemplateArgument(Param, DefaultTInfo)) { 512 Param->setInvalidDecl(); 513 return DeclPtrTy::make(Param);; 514 } 515 516 Param->setDefaultArgument(DefaultTInfo, false); 517 } 518 519 return DeclPtrTy::make(Param); 520} 521 522/// \brief Check that the type of a non-type template parameter is 523/// well-formed. 524/// 525/// \returns the (possibly-promoted) parameter type if valid; 526/// otherwise, produces a diagnostic and returns a NULL type. 527QualType 528Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { 529 // We don't allow variably-modified types as the type of non-type template 530 // parameters. 531 if (T->isVariablyModifiedType()) { 532 Diag(Loc, diag::err_variably_modified_nontype_template_param) 533 << T; 534 return QualType(); 535 } 536 537 // C++ [temp.param]p4: 538 // 539 // A non-type template-parameter shall have one of the following 540 // (optionally cv-qualified) types: 541 // 542 // -- integral or enumeration type, 543 if (T->isIntegralOrEnumerationType() || 544 // -- pointer to object or pointer to function, 545 (T->isPointerType() && 546 (T->getAs<PointerType>()->getPointeeType()->isObjectType() || 547 T->getAs<PointerType>()->getPointeeType()->isFunctionType())) || 548 // -- reference to object or reference to function, 549 T->isReferenceType() || 550 // -- pointer to member. 551 T->isMemberPointerType() || 552 // If T is a dependent type, we can't do the check now, so we 553 // assume that it is well-formed. 554 T->isDependentType()) 555 return T; 556 // C++ [temp.param]p8: 557 // 558 // A non-type template-parameter of type "array of T" or 559 // "function returning T" is adjusted to be of type "pointer to 560 // T" or "pointer to function returning T", respectively. 561 else if (T->isArrayType()) 562 // FIXME: Keep the type prior to promotion? 563 return Context.getArrayDecayedType(T); 564 else if (T->isFunctionType()) 565 // FIXME: Keep the type prior to promotion? 566 return Context.getPointerType(T); 567 568 Diag(Loc, diag::err_template_nontype_parm_bad_type) 569 << T; 570 571 return QualType(); 572} 573 574Sema::DeclPtrTy Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, 575 unsigned Depth, 576 unsigned Position, 577 SourceLocation EqualLoc, 578 ExprArg DefaultArg) { 579 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 580 QualType T = TInfo->getType(); 581 582 assert(S->isTemplateParamScope() && 583 "Non-type template parameter not in template parameter scope!"); 584 bool Invalid = false; 585 586 IdentifierInfo *ParamName = D.getIdentifier(); 587 if (ParamName) { 588 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(), 589 LookupOrdinaryName, 590 ForRedeclaration); 591 if (PrevDecl && PrevDecl->isTemplateParameter()) 592 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 593 PrevDecl); 594 } 595 596 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); 597 if (T.isNull()) { 598 T = Context.IntTy; // Recover with an 'int' type. 599 Invalid = true; 600 } 601 602 NonTypeTemplateParmDecl *Param 603 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 604 D.getIdentifierLoc(), 605 Depth, Position, ParamName, T, TInfo); 606 if (Invalid) 607 Param->setInvalidDecl(); 608 609 if (D.getIdentifier()) { 610 // Add the template parameter into the current scope. 611 S->AddDecl(DeclPtrTy::make(Param)); 612 IdResolver.AddDecl(Param); 613 } 614 615 // Check the well-formedness of the default template argument, if provided. 616 if (Expr *Default = static_cast<Expr *>(DefaultArg.get())) { 617 TemplateArgument Converted; 618 if (CheckTemplateArgument(Param, Param->getType(), Default, Converted)) { 619 Param->setInvalidDecl(); 620 return DeclPtrTy::make(Param);; 621 } 622 623 Param->setDefaultArgument(DefaultArg.takeAs<Expr>(), false); 624 } 625 626 return DeclPtrTy::make(Param); 627} 628 629/// ActOnTemplateTemplateParameter - Called when a C++ template template 630/// parameter (e.g. T in template <template <typename> class T> class array) 631/// has been parsed. S is the current scope. 632Sema::DeclPtrTy Sema::ActOnTemplateTemplateParameter(Scope* S, 633 SourceLocation TmpLoc, 634 TemplateParamsTy *Params, 635 IdentifierInfo *Name, 636 SourceLocation NameLoc, 637 unsigned Depth, 638 unsigned Position, 639 SourceLocation EqualLoc, 640 const ParsedTemplateArgument &Default) { 641 assert(S->isTemplateParamScope() && 642 "Template template parameter not in template parameter scope!"); 643 644 // Construct the parameter object. 645 TemplateTemplateParmDecl *Param = 646 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 647 TmpLoc, Depth, Position, Name, 648 (TemplateParameterList*)Params); 649 650 // If the template template parameter has a name, then link the identifier 651 // into the scope and lookup mechanisms. 652 if (Name) { 653 S->AddDecl(DeclPtrTy::make(Param)); 654 IdResolver.AddDecl(Param); 655 } 656 657 if (!Default.isInvalid()) { 658 // Check only that we have a template template argument. We don't want to 659 // try to check well-formedness now, because our template template parameter 660 // might have dependent types in its template parameters, which we wouldn't 661 // be able to match now. 662 // 663 // If none of the template template parameter's template arguments mention 664 // other template parameters, we could actually perform more checking here. 665 // However, it isn't worth doing. 666 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); 667 if (DefaultArg.getArgument().getAsTemplate().isNull()) { 668 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) 669 << DefaultArg.getSourceRange(); 670 return DeclPtrTy::make(Param); 671 } 672 673 Param->setDefaultArgument(DefaultArg, false); 674 } 675 676 return DeclPtrTy::make(Param); 677} 678 679/// ActOnTemplateParameterList - Builds a TemplateParameterList that 680/// contains the template parameters in Params/NumParams. 681Sema::TemplateParamsTy * 682Sema::ActOnTemplateParameterList(unsigned Depth, 683 SourceLocation ExportLoc, 684 SourceLocation TemplateLoc, 685 SourceLocation LAngleLoc, 686 DeclPtrTy *Params, unsigned NumParams, 687 SourceLocation RAngleLoc) { 688 if (ExportLoc.isValid()) 689 Diag(ExportLoc, diag::warn_template_export_unsupported); 690 691 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, 692 (NamedDecl**)Params, NumParams, 693 RAngleLoc); 694} 695 696static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) { 697 if (SS.isSet()) 698 T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 699 SS.getRange()); 700} 701 702Sema::DeclResult 703Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, 704 SourceLocation KWLoc, CXXScopeSpec &SS, 705 IdentifierInfo *Name, SourceLocation NameLoc, 706 AttributeList *Attr, 707 TemplateParameterList *TemplateParams, 708 AccessSpecifier AS) { 709 assert(TemplateParams && TemplateParams->size() > 0 && 710 "No template parameters"); 711 assert(TUK != TUK_Reference && "Can only declare or define class templates"); 712 bool Invalid = false; 713 714 // Check that we can declare a template here. 715 if (CheckTemplateDeclScope(S, TemplateParams)) 716 return true; 717 718 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 719 assert(Kind != TTK_Enum && "can't build template of enumerated type"); 720 721 // There is no such thing as an unnamed class template. 722 if (!Name) { 723 Diag(KWLoc, diag::err_template_unnamed_class); 724 return true; 725 } 726 727 // Find any previous declaration with this name. 728 DeclContext *SemanticContext; 729 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, 730 ForRedeclaration); 731 if (SS.isNotEmpty() && !SS.isInvalid()) { 732 SemanticContext = computeDeclContext(SS, true); 733 if (!SemanticContext) { 734 // FIXME: Produce a reasonable diagnostic here 735 return true; 736 } 737 738 if (RequireCompleteDeclContext(SS, SemanticContext)) 739 return true; 740 741 LookupQualifiedName(Previous, SemanticContext); 742 } else { 743 SemanticContext = CurContext; 744 LookupName(Previous, S); 745 } 746 747 if (Previous.isAmbiguous()) 748 return true; 749 750 NamedDecl *PrevDecl = 0; 751 if (Previous.begin() != Previous.end()) 752 PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 753 754 // If there is a previous declaration with the same name, check 755 // whether this is a valid redeclaration. 756 ClassTemplateDecl *PrevClassTemplate 757 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); 758 759 // We may have found the injected-class-name of a class template, 760 // class template partial specialization, or class template specialization. 761 // In these cases, grab the template that is being defined or specialized. 762 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && 763 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { 764 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); 765 PrevClassTemplate 766 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); 767 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { 768 PrevClassTemplate 769 = cast<ClassTemplateSpecializationDecl>(PrevDecl) 770 ->getSpecializedTemplate(); 771 } 772 } 773 774 if (TUK == TUK_Friend) { 775 // C++ [namespace.memdef]p3: 776 // [...] When looking for a prior declaration of a class or a function 777 // declared as a friend, and when the name of the friend class or 778 // function is neither a qualified name nor a template-id, scopes outside 779 // the innermost enclosing namespace scope are not considered. 780 if (!SS.isSet()) { 781 DeclContext *OutermostContext = CurContext; 782 while (!OutermostContext->isFileContext()) 783 OutermostContext = OutermostContext->getLookupParent(); 784 785 if (PrevDecl && 786 (OutermostContext->Equals(PrevDecl->getDeclContext()) || 787 OutermostContext->Encloses(PrevDecl->getDeclContext()))) { 788 SemanticContext = PrevDecl->getDeclContext(); 789 } else { 790 // Declarations in outer scopes don't matter. However, the outermost 791 // context we computed is the semantic context for our new 792 // declaration. 793 PrevDecl = PrevClassTemplate = 0; 794 SemanticContext = OutermostContext; 795 } 796 } 797 798 if (CurContext->isDependentContext()) { 799 // If this is a dependent context, we don't want to link the friend 800 // class template to the template in scope, because that would perform 801 // checking of the template parameter lists that can't be performed 802 // until the outer context is instantiated. 803 PrevDecl = PrevClassTemplate = 0; 804 } 805 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) 806 PrevDecl = PrevClassTemplate = 0; 807 808 if (PrevClassTemplate) { 809 // Ensure that the template parameter lists are compatible. 810 if (!TemplateParameterListsAreEqual(TemplateParams, 811 PrevClassTemplate->getTemplateParameters(), 812 /*Complain=*/true, 813 TPL_TemplateMatch)) 814 return true; 815 816 // C++ [temp.class]p4: 817 // In a redeclaration, partial specialization, explicit 818 // specialization or explicit instantiation of a class template, 819 // the class-key shall agree in kind with the original class 820 // template declaration (7.1.5.3). 821 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); 822 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) { 823 Diag(KWLoc, diag::err_use_with_wrong_tag) 824 << Name 825 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName()); 826 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); 827 Kind = PrevRecordDecl->getTagKind(); 828 } 829 830 // Check for redefinition of this class template. 831 if (TUK == TUK_Definition) { 832 if (TagDecl *Def = PrevRecordDecl->getDefinition()) { 833 Diag(NameLoc, diag::err_redefinition) << Name; 834 Diag(Def->getLocation(), diag::note_previous_definition); 835 // FIXME: Would it make sense to try to "forget" the previous 836 // definition, as part of error recovery? 837 return true; 838 } 839 } 840 } else if (PrevDecl && PrevDecl->isTemplateParameter()) { 841 // Maybe we will complain about the shadowed template parameter. 842 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 843 // Just pretend that we didn't see the previous declaration. 844 PrevDecl = 0; 845 } else if (PrevDecl) { 846 // C++ [temp]p5: 847 // A class template shall not have the same name as any other 848 // template, class, function, object, enumeration, enumerator, 849 // namespace, or type in the same scope (3.3), except as specified 850 // in (14.5.4). 851 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 852 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 853 return true; 854 } 855 856 // Check the template parameter list of this declaration, possibly 857 // merging in the template parameter list from the previous class 858 // template declaration. 859 if (CheckTemplateParameterList(TemplateParams, 860 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0, 861 TPC_ClassTemplate)) 862 Invalid = true; 863 864 if (SS.isSet()) { 865 // If the name of the template was qualified, we must be defining the 866 // template out-of-line. 867 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate && 868 !(TUK == TUK_Friend && CurContext->isDependentContext())) 869 Diag(NameLoc, diag::err_member_def_does_not_match) 870 << Name << SemanticContext << SS.getRange(); 871 } 872 873 CXXRecordDecl *NewClass = 874 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc, 875 PrevClassTemplate? 876 PrevClassTemplate->getTemplatedDecl() : 0, 877 /*DelayTypeCreation=*/true); 878 SetNestedNameSpecifier(NewClass, SS); 879 880 ClassTemplateDecl *NewTemplate 881 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, 882 DeclarationName(Name), TemplateParams, 883 NewClass, PrevClassTemplate); 884 NewClass->setDescribedClassTemplate(NewTemplate); 885 886 // Build the type for the class template declaration now. 887 QualType T = NewTemplate->getInjectedClassNameSpecialization(); 888 T = Context.getInjectedClassNameType(NewClass, T); 889 assert(T->isDependentType() && "Class template type is not dependent?"); 890 (void)T; 891 892 // If we are providing an explicit specialization of a member that is a 893 // class template, make a note of that. 894 if (PrevClassTemplate && 895 PrevClassTemplate->getInstantiatedFromMemberTemplate()) 896 PrevClassTemplate->setMemberSpecialization(); 897 898 // Set the access specifier. 899 if (!Invalid && TUK != TUK_Friend) 900 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); 901 902 // Set the lexical context of these templates 903 NewClass->setLexicalDeclContext(CurContext); 904 NewTemplate->setLexicalDeclContext(CurContext); 905 906 if (TUK == TUK_Definition) 907 NewClass->startDefinition(); 908 909 if (Attr) 910 ProcessDeclAttributeList(S, NewClass, Attr); 911 912 if (TUK != TUK_Friend) 913 PushOnScopeChains(NewTemplate, S); 914 else { 915 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { 916 NewTemplate->setAccess(PrevClassTemplate->getAccess()); 917 NewClass->setAccess(PrevClassTemplate->getAccess()); 918 } 919 920 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ 921 PrevClassTemplate != NULL); 922 923 // Friend templates are visible in fairly strange ways. 924 if (!CurContext->isDependentContext()) { 925 DeclContext *DC = SemanticContext->getLookupContext(); 926 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false); 927 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 928 PushOnScopeChains(NewTemplate, EnclosingScope, 929 /* AddToContext = */ false); 930 } 931 932 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 933 NewClass->getLocation(), 934 NewTemplate, 935 /*FIXME:*/NewClass->getLocation()); 936 Friend->setAccess(AS_public); 937 CurContext->addDecl(Friend); 938 } 939 940 if (Invalid) { 941 NewTemplate->setInvalidDecl(); 942 NewClass->setInvalidDecl(); 943 } 944 return DeclPtrTy::make(NewTemplate); 945} 946 947/// \brief Diagnose the presence of a default template argument on a 948/// template parameter, which is ill-formed in certain contexts. 949/// 950/// \returns true if the default template argument should be dropped. 951static bool DiagnoseDefaultTemplateArgument(Sema &S, 952 Sema::TemplateParamListContext TPC, 953 SourceLocation ParamLoc, 954 SourceRange DefArgRange) { 955 switch (TPC) { 956 case Sema::TPC_ClassTemplate: 957 return false; 958 959 case Sema::TPC_FunctionTemplate: 960 // C++ [temp.param]p9: 961 // A default template-argument shall not be specified in a 962 // function template declaration or a function template 963 // definition [...] 964 // (This sentence is not in C++0x, per DR226). 965 if (!S.getLangOptions().CPlusPlus0x) 966 S.Diag(ParamLoc, 967 diag::err_template_parameter_default_in_function_template) 968 << DefArgRange; 969 return false; 970 971 case Sema::TPC_ClassTemplateMember: 972 // C++0x [temp.param]p9: 973 // A default template-argument shall not be specified in the 974 // template-parameter-lists of the definition of a member of a 975 // class template that appears outside of the member's class. 976 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member) 977 << DefArgRange; 978 return true; 979 980 case Sema::TPC_FriendFunctionTemplate: 981 // C++ [temp.param]p9: 982 // A default template-argument shall not be specified in a 983 // friend template declaration. 984 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template) 985 << DefArgRange; 986 return true; 987 988 // FIXME: C++0x [temp.param]p9 allows default template-arguments 989 // for friend function templates if there is only a single 990 // declaration (and it is a definition). Strange! 991 } 992 993 return false; 994} 995 996/// \brief Checks the validity of a template parameter list, possibly 997/// considering the template parameter list from a previous 998/// declaration. 999/// 1000/// If an "old" template parameter list is provided, it must be 1001/// equivalent (per TemplateParameterListsAreEqual) to the "new" 1002/// template parameter list. 1003/// 1004/// \param NewParams Template parameter list for a new template 1005/// declaration. This template parameter list will be updated with any 1006/// default arguments that are carried through from the previous 1007/// template parameter list. 1008/// 1009/// \param OldParams If provided, template parameter list from a 1010/// previous declaration of the same template. Default template 1011/// arguments will be merged from the old template parameter list to 1012/// the new template parameter list. 1013/// 1014/// \param TPC Describes the context in which we are checking the given 1015/// template parameter list. 1016/// 1017/// \returns true if an error occurred, false otherwise. 1018bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, 1019 TemplateParameterList *OldParams, 1020 TemplateParamListContext TPC) { 1021 bool Invalid = false; 1022 1023 // C++ [temp.param]p10: 1024 // The set of default template-arguments available for use with a 1025 // template declaration or definition is obtained by merging the 1026 // default arguments from the definition (if in scope) and all 1027 // declarations in scope in the same way default function 1028 // arguments are (8.3.6). 1029 bool SawDefaultArgument = false; 1030 SourceLocation PreviousDefaultArgLoc; 1031 1032 bool SawParameterPack = false; 1033 SourceLocation ParameterPackLoc; 1034 1035 // Dummy initialization to avoid warnings. 1036 TemplateParameterList::iterator OldParam = NewParams->end(); 1037 if (OldParams) 1038 OldParam = OldParams->begin(); 1039 1040 for (TemplateParameterList::iterator NewParam = NewParams->begin(), 1041 NewParamEnd = NewParams->end(); 1042 NewParam != NewParamEnd; ++NewParam) { 1043 // Variables used to diagnose redundant default arguments 1044 bool RedundantDefaultArg = false; 1045 SourceLocation OldDefaultLoc; 1046 SourceLocation NewDefaultLoc; 1047 1048 // Variables used to diagnose missing default arguments 1049 bool MissingDefaultArg = false; 1050 1051 // C++0x [temp.param]p11: 1052 // If a template parameter of a class template is a template parameter pack, 1053 // it must be the last template parameter. 1054 if (SawParameterPack) { 1055 Diag(ParameterPackLoc, 1056 diag::err_template_param_pack_must_be_last_template_parameter); 1057 Invalid = true; 1058 } 1059 1060 if (TemplateTypeParmDecl *NewTypeParm 1061 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { 1062 // Check the presence of a default argument here. 1063 if (NewTypeParm->hasDefaultArgument() && 1064 DiagnoseDefaultTemplateArgument(*this, TPC, 1065 NewTypeParm->getLocation(), 1066 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc() 1067 .getSourceRange())) 1068 NewTypeParm->removeDefaultArgument(); 1069 1070 // Merge default arguments for template type parameters. 1071 TemplateTypeParmDecl *OldTypeParm 1072 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; 1073 1074 if (NewTypeParm->isParameterPack()) { 1075 assert(!NewTypeParm->hasDefaultArgument() && 1076 "Parameter packs can't have a default argument!"); 1077 SawParameterPack = true; 1078 ParameterPackLoc = NewTypeParm->getLocation(); 1079 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && 1080 NewTypeParm->hasDefaultArgument()) { 1081 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); 1082 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); 1083 SawDefaultArgument = true; 1084 RedundantDefaultArg = true; 1085 PreviousDefaultArgLoc = NewDefaultLoc; 1086 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { 1087 // Merge the default argument from the old declaration to the 1088 // new declaration. 1089 SawDefaultArgument = true; 1090 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), 1091 true); 1092 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); 1093 } else if (NewTypeParm->hasDefaultArgument()) { 1094 SawDefaultArgument = true; 1095 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); 1096 } else if (SawDefaultArgument) 1097 MissingDefaultArg = true; 1098 } else if (NonTypeTemplateParmDecl *NewNonTypeParm 1099 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { 1100 // Check the presence of a default argument here. 1101 if (NewNonTypeParm->hasDefaultArgument() && 1102 DiagnoseDefaultTemplateArgument(*this, TPC, 1103 NewNonTypeParm->getLocation(), 1104 NewNonTypeParm->getDefaultArgument()->getSourceRange())) { 1105 NewNonTypeParm->getDefaultArgument()->Destroy(Context); 1106 NewNonTypeParm->removeDefaultArgument(); 1107 } 1108 1109 // Merge default arguments for non-type template parameters 1110 NonTypeTemplateParmDecl *OldNonTypeParm 1111 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; 1112 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && 1113 NewNonTypeParm->hasDefaultArgument()) { 1114 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1115 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1116 SawDefaultArgument = true; 1117 RedundantDefaultArg = true; 1118 PreviousDefaultArgLoc = NewDefaultLoc; 1119 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { 1120 // Merge the default argument from the old declaration to the 1121 // new declaration. 1122 SawDefaultArgument = true; 1123 // FIXME: We need to create a new kind of "default argument" 1124 // expression that points to a previous template template 1125 // parameter. 1126 NewNonTypeParm->setDefaultArgument( 1127 OldNonTypeParm->getDefaultArgument(), 1128 /*Inherited=*/ true); 1129 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1130 } else if (NewNonTypeParm->hasDefaultArgument()) { 1131 SawDefaultArgument = true; 1132 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1133 } else if (SawDefaultArgument) 1134 MissingDefaultArg = true; 1135 } else { 1136 // Check the presence of a default argument here. 1137 TemplateTemplateParmDecl *NewTemplateParm 1138 = cast<TemplateTemplateParmDecl>(*NewParam); 1139 if (NewTemplateParm->hasDefaultArgument() && 1140 DiagnoseDefaultTemplateArgument(*this, TPC, 1141 NewTemplateParm->getLocation(), 1142 NewTemplateParm->getDefaultArgument().getSourceRange())) 1143 NewTemplateParm->removeDefaultArgument(); 1144 1145 // Merge default arguments for template template parameters 1146 TemplateTemplateParmDecl *OldTemplateParm 1147 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; 1148 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && 1149 NewTemplateParm->hasDefaultArgument()) { 1150 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); 1151 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); 1152 SawDefaultArgument = true; 1153 RedundantDefaultArg = true; 1154 PreviousDefaultArgLoc = NewDefaultLoc; 1155 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { 1156 // Merge the default argument from the old declaration to the 1157 // new declaration. 1158 SawDefaultArgument = true; 1159 // FIXME: We need to create a new kind of "default argument" expression 1160 // that points to a previous template template parameter. 1161 NewTemplateParm->setDefaultArgument( 1162 OldTemplateParm->getDefaultArgument(), 1163 /*Inherited=*/ true); 1164 PreviousDefaultArgLoc 1165 = OldTemplateParm->getDefaultArgument().getLocation(); 1166 } else if (NewTemplateParm->hasDefaultArgument()) { 1167 SawDefaultArgument = true; 1168 PreviousDefaultArgLoc 1169 = NewTemplateParm->getDefaultArgument().getLocation(); 1170 } else if (SawDefaultArgument) 1171 MissingDefaultArg = true; 1172 } 1173 1174 if (RedundantDefaultArg) { 1175 // C++ [temp.param]p12: 1176 // A template-parameter shall not be given default arguments 1177 // by two different declarations in the same scope. 1178 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); 1179 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); 1180 Invalid = true; 1181 } else if (MissingDefaultArg) { 1182 // C++ [temp.param]p11: 1183 // If a template-parameter has a default template-argument, 1184 // all subsequent template-parameters shall have a default 1185 // template-argument supplied. 1186 Diag((*NewParam)->getLocation(), 1187 diag::err_template_param_default_arg_missing); 1188 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); 1189 Invalid = true; 1190 } 1191 1192 // If we have an old template parameter list that we're merging 1193 // in, move on to the next parameter. 1194 if (OldParams) 1195 ++OldParam; 1196 } 1197 1198 return Invalid; 1199} 1200 1201/// \brief Match the given template parameter lists to the given scope 1202/// specifier, returning the template parameter list that applies to the 1203/// name. 1204/// 1205/// \param DeclStartLoc the start of the declaration that has a scope 1206/// specifier or a template parameter list. 1207/// 1208/// \param SS the scope specifier that will be matched to the given template 1209/// parameter lists. This scope specifier precedes a qualified name that is 1210/// being declared. 1211/// 1212/// \param ParamLists the template parameter lists, from the outermost to the 1213/// innermost template parameter lists. 1214/// 1215/// \param NumParamLists the number of template parameter lists in ParamLists. 1216/// 1217/// \param IsFriend Whether to apply the slightly different rules for 1218/// matching template parameters to scope specifiers in friend 1219/// declarations. 1220/// 1221/// \param IsExplicitSpecialization will be set true if the entity being 1222/// declared is an explicit specialization, false otherwise. 1223/// 1224/// \returns the template parameter list, if any, that corresponds to the 1225/// name that is preceded by the scope specifier @p SS. This template 1226/// parameter list may be have template parameters (if we're declaring a 1227/// template) or may have no template parameters (if we're declaring a 1228/// template specialization), or may be NULL (if we were's declaring isn't 1229/// itself a template). 1230TemplateParameterList * 1231Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, 1232 const CXXScopeSpec &SS, 1233 TemplateParameterList **ParamLists, 1234 unsigned NumParamLists, 1235 bool IsFriend, 1236 bool &IsExplicitSpecialization, 1237 bool &Invalid) { 1238 IsExplicitSpecialization = false; 1239 1240 // Find the template-ids that occur within the nested-name-specifier. These 1241 // template-ids will match up with the template parameter lists. 1242 llvm::SmallVector<const TemplateSpecializationType *, 4> 1243 TemplateIdsInSpecifier; 1244 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4> 1245 ExplicitSpecializationsInSpecifier; 1246 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 1247 NNS; NNS = NNS->getPrefix()) { 1248 const Type *T = NNS->getAsType(); 1249 if (!T) break; 1250 1251 // C++0x [temp.expl.spec]p17: 1252 // A member or a member template may be nested within many 1253 // enclosing class templates. In an explicit specialization for 1254 // such a member, the member declaration shall be preceded by a 1255 // template<> for each enclosing class template that is 1256 // explicitly specialized. 1257 // 1258 // Following the existing practice of GNU and EDG, we allow a typedef of a 1259 // template specialization type. 1260 if (const TypedefType *TT = dyn_cast<TypedefType>(T)) 1261 T = TT->LookThroughTypedefs().getTypePtr(); 1262 1263 if (const TemplateSpecializationType *SpecType 1264 = dyn_cast<TemplateSpecializationType>(T)) { 1265 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl(); 1266 if (!Template) 1267 continue; // FIXME: should this be an error? probably... 1268 1269 if (const RecordType *Record = SpecType->getAs<RecordType>()) { 1270 ClassTemplateSpecializationDecl *SpecDecl 1271 = cast<ClassTemplateSpecializationDecl>(Record->getDecl()); 1272 // If the nested name specifier refers to an explicit specialization, 1273 // we don't need a template<> header. 1274 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) { 1275 ExplicitSpecializationsInSpecifier.push_back(SpecDecl); 1276 continue; 1277 } 1278 } 1279 1280 TemplateIdsInSpecifier.push_back(SpecType); 1281 } 1282 } 1283 1284 // Reverse the list of template-ids in the scope specifier, so that we can 1285 // more easily match up the template-ids and the template parameter lists. 1286 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end()); 1287 1288 SourceLocation FirstTemplateLoc = DeclStartLoc; 1289 if (NumParamLists) 1290 FirstTemplateLoc = ParamLists[0]->getTemplateLoc(); 1291 1292 // Match the template-ids found in the specifier to the template parameter 1293 // lists. 1294 unsigned Idx = 0; 1295 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size(); 1296 Idx != NumTemplateIds; ++Idx) { 1297 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0); 1298 bool DependentTemplateId = TemplateId->isDependentType(); 1299 if (Idx >= NumParamLists) { 1300 // We have a template-id without a corresponding template parameter 1301 // list. 1302 1303 // ...which is fine if this is a friend declaration. 1304 if (IsFriend) { 1305 IsExplicitSpecialization = true; 1306 break; 1307 } 1308 1309 if (DependentTemplateId) { 1310 // FIXME: the location information here isn't great. 1311 Diag(SS.getRange().getBegin(), 1312 diag::err_template_spec_needs_template_parameters) 1313 << TemplateId 1314 << SS.getRange(); 1315 Invalid = true; 1316 } else { 1317 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header) 1318 << SS.getRange() 1319 << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> "); 1320 IsExplicitSpecialization = true; 1321 } 1322 return 0; 1323 } 1324 1325 // Check the template parameter list against its corresponding template-id. 1326 if (DependentTemplateId) { 1327 TemplateParameterList *ExpectedTemplateParams = 0; 1328 1329 // Are there cases in (e.g.) friends where this won't match? 1330 if (const InjectedClassNameType *Injected 1331 = TemplateId->getAs<InjectedClassNameType>()) { 1332 CXXRecordDecl *Record = Injected->getDecl(); 1333 if (ClassTemplatePartialSpecializationDecl *Partial = 1334 dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) 1335 ExpectedTemplateParams = Partial->getTemplateParameters(); 1336 else 1337 ExpectedTemplateParams = Record->getDescribedClassTemplate() 1338 ->getTemplateParameters(); 1339 } 1340 1341 if (ExpectedTemplateParams) 1342 TemplateParameterListsAreEqual(ParamLists[Idx], 1343 ExpectedTemplateParams, 1344 true, TPL_TemplateMatch); 1345 1346 CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember); 1347 } else if (ParamLists[Idx]->size() > 0) 1348 Diag(ParamLists[Idx]->getTemplateLoc(), 1349 diag::err_template_param_list_matches_nontemplate) 1350 << TemplateId 1351 << ParamLists[Idx]->getSourceRange(); 1352 else 1353 IsExplicitSpecialization = true; 1354 } 1355 1356 // If there were at least as many template-ids as there were template 1357 // parameter lists, then there are no template parameter lists remaining for 1358 // the declaration itself. 1359 if (Idx >= NumParamLists) 1360 return 0; 1361 1362 // If there were too many template parameter lists, complain about that now. 1363 if (Idx != NumParamLists - 1) { 1364 while (Idx < NumParamLists - 1) { 1365 bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0; 1366 Diag(ParamLists[Idx]->getTemplateLoc(), 1367 isExplicitSpecHeader? diag::warn_template_spec_extra_headers 1368 : diag::err_template_spec_extra_headers) 1369 << SourceRange(ParamLists[Idx]->getTemplateLoc(), 1370 ParamLists[Idx]->getRAngleLoc()); 1371 1372 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) { 1373 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(), 1374 diag::note_explicit_template_spec_does_not_need_header) 1375 << ExplicitSpecializationsInSpecifier.back(); 1376 ExplicitSpecializationsInSpecifier.pop_back(); 1377 } 1378 1379 // We have a template parameter list with no corresponding scope, which 1380 // means that the resulting template declaration can't be instantiated 1381 // properly (we'll end up with dependent nodes when we shouldn't). 1382 if (!isExplicitSpecHeader) 1383 Invalid = true; 1384 1385 ++Idx; 1386 } 1387 } 1388 1389 // Return the last template parameter list, which corresponds to the 1390 // entity being declared. 1391 return ParamLists[NumParamLists - 1]; 1392} 1393 1394QualType Sema::CheckTemplateIdType(TemplateName Name, 1395 SourceLocation TemplateLoc, 1396 const TemplateArgumentListInfo &TemplateArgs) { 1397 TemplateDecl *Template = Name.getAsTemplateDecl(); 1398 if (!Template) { 1399 // The template name does not resolve to a template, so we just 1400 // build a dependent template-id type. 1401 return Context.getTemplateSpecializationType(Name, TemplateArgs); 1402 } 1403 1404 // Check that the template argument list is well-formed for this 1405 // template. 1406 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(), 1407 TemplateArgs.size()); 1408 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs, 1409 false, Converted)) 1410 return QualType(); 1411 1412 assert((Converted.structuredSize() == 1413 Template->getTemplateParameters()->size()) && 1414 "Converted template argument list is too short!"); 1415 1416 QualType CanonType; 1417 1418 if (Name.isDependent() || 1419 TemplateSpecializationType::anyDependentTemplateArguments( 1420 TemplateArgs)) { 1421 // This class template specialization is a dependent 1422 // type. Therefore, its canonical type is another class template 1423 // specialization type that contains all of the converted 1424 // arguments in canonical form. This ensures that, e.g., A<T> and 1425 // A<T, T> have identical types when A is declared as: 1426 // 1427 // template<typename T, typename U = T> struct A; 1428 TemplateName CanonName = Context.getCanonicalTemplateName(Name); 1429 CanonType = Context.getTemplateSpecializationType(CanonName, 1430 Converted.getFlatArguments(), 1431 Converted.flatSize()); 1432 1433 // FIXME: CanonType is not actually the canonical type, and unfortunately 1434 // it is a TemplateSpecializationType that we will never use again. 1435 // In the future, we need to teach getTemplateSpecializationType to only 1436 // build the canonical type and return that to us. 1437 CanonType = Context.getCanonicalType(CanonType); 1438 1439 // This might work out to be a current instantiation, in which 1440 // case the canonical type needs to be the InjectedClassNameType. 1441 // 1442 // TODO: in theory this could be a simple hashtable lookup; most 1443 // changes to CurContext don't change the set of current 1444 // instantiations. 1445 if (isa<ClassTemplateDecl>(Template)) { 1446 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) { 1447 // If we get out to a namespace, we're done. 1448 if (Ctx->isFileContext()) break; 1449 1450 // If this isn't a record, keep looking. 1451 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx); 1452 if (!Record) continue; 1453 1454 // Look for one of the two cases with InjectedClassNameTypes 1455 // and check whether it's the same template. 1456 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) && 1457 !Record->getDescribedClassTemplate()) 1458 continue; 1459 1460 // Fetch the injected class name type and check whether its 1461 // injected type is equal to the type we just built. 1462 QualType ICNT = Context.getTypeDeclType(Record); 1463 QualType Injected = cast<InjectedClassNameType>(ICNT) 1464 ->getInjectedSpecializationType(); 1465 1466 if (CanonType != Injected->getCanonicalTypeInternal()) 1467 continue; 1468 1469 // If so, the canonical type of this TST is the injected 1470 // class name type of the record we just found. 1471 assert(ICNT.isCanonical()); 1472 CanonType = ICNT; 1473 break; 1474 } 1475 } 1476 } else if (ClassTemplateDecl *ClassTemplate 1477 = dyn_cast<ClassTemplateDecl>(Template)) { 1478 // Find the class template specialization declaration that 1479 // corresponds to these arguments. 1480 llvm::FoldingSetNodeID ID; 1481 ClassTemplateSpecializationDecl::Profile(ID, 1482 Converted.getFlatArguments(), 1483 Converted.flatSize(), 1484 Context); 1485 void *InsertPos = 0; 1486 ClassTemplateSpecializationDecl *Decl 1487 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 1488 if (!Decl) { 1489 // This is the first time we have referenced this class template 1490 // specialization. Create the canonical declaration and add it to 1491 // the set of specializations. 1492 Decl = ClassTemplateSpecializationDecl::Create(Context, 1493 ClassTemplate->getTemplatedDecl()->getTagKind(), 1494 ClassTemplate->getDeclContext(), 1495 ClassTemplate->getLocation(), 1496 ClassTemplate, 1497 Converted, 0); 1498 ClassTemplate->getSpecializations().InsertNode(Decl, InsertPos); 1499 Decl->setLexicalDeclContext(CurContext); 1500 } 1501 1502 CanonType = Context.getTypeDeclType(Decl); 1503 assert(isa<RecordType>(CanonType) && 1504 "type of non-dependent specialization is not a RecordType"); 1505 } 1506 1507 // Build the fully-sugared type for this class template 1508 // specialization, which refers back to the class template 1509 // specialization we created or found. 1510 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); 1511} 1512 1513Action::TypeResult 1514Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc, 1515 SourceLocation LAngleLoc, 1516 ASTTemplateArgsPtr TemplateArgsIn, 1517 SourceLocation RAngleLoc) { 1518 TemplateName Template = TemplateD.getAsVal<TemplateName>(); 1519 1520 // Translate the parser's template argument list in our AST format. 1521 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 1522 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 1523 1524 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); 1525 TemplateArgsIn.release(); 1526 1527 if (Result.isNull()) 1528 return true; 1529 1530 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result); 1531 TemplateSpecializationTypeLoc TL 1532 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc()); 1533 TL.setTemplateNameLoc(TemplateLoc); 1534 TL.setLAngleLoc(LAngleLoc); 1535 TL.setRAngleLoc(RAngleLoc); 1536 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) 1537 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); 1538 1539 return CreateLocInfoType(Result, DI).getAsOpaquePtr(); 1540} 1541 1542Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult, 1543 TagUseKind TUK, 1544 DeclSpec::TST TagSpec, 1545 SourceLocation TagLoc) { 1546 if (TypeResult.isInvalid()) 1547 return Sema::TypeResult(); 1548 1549 // FIXME: preserve source info, ideally without copying the DI. 1550 TypeSourceInfo *DI; 1551 QualType Type = GetTypeFromParser(TypeResult.get(), &DI); 1552 1553 // Verify the tag specifier. 1554 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 1555 1556 if (const RecordType *RT = Type->getAs<RecordType>()) { 1557 RecordDecl *D = RT->getDecl(); 1558 1559 IdentifierInfo *Id = D->getIdentifier(); 1560 assert(Id && "templated class must have an identifier"); 1561 1562 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) { 1563 Diag(TagLoc, diag::err_use_with_wrong_tag) 1564 << Type 1565 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName()); 1566 Diag(D->getLocation(), diag::note_previous_use); 1567 } 1568 } 1569 1570 ElaboratedTypeKeyword Keyword 1571 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind); 1572 QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type); 1573 1574 return ElabType.getAsOpaquePtr(); 1575} 1576 1577Sema::OwningExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS, 1578 LookupResult &R, 1579 bool RequiresADL, 1580 const TemplateArgumentListInfo &TemplateArgs) { 1581 // FIXME: Can we do any checking at this point? I guess we could check the 1582 // template arguments that we have against the template name, if the template 1583 // name refers to a single template. That's not a terribly common case, 1584 // though. 1585 1586 // These should be filtered out by our callers. 1587 assert(!R.empty() && "empty lookup results when building templateid"); 1588 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid"); 1589 1590 NestedNameSpecifier *Qualifier = 0; 1591 SourceRange QualifierRange; 1592 if (SS.isSet()) { 1593 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 1594 QualifierRange = SS.getRange(); 1595 } 1596 1597 // We don't want lookup warnings at this point. 1598 R.suppressDiagnostics(); 1599 1600 bool Dependent 1601 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 1602 &TemplateArgs); 1603 UnresolvedLookupExpr *ULE 1604 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1605 Qualifier, QualifierRange, 1606 R.getLookupName(), R.getNameLoc(), 1607 RequiresADL, TemplateArgs, 1608 R.begin(), R.end()); 1609 1610 return Owned(ULE); 1611} 1612 1613// We actually only call this from template instantiation. 1614Sema::OwningExprResult 1615Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS, 1616 DeclarationName Name, 1617 SourceLocation NameLoc, 1618 const TemplateArgumentListInfo &TemplateArgs) { 1619 DeclContext *DC; 1620 if (!(DC = computeDeclContext(SS, false)) || 1621 DC->isDependentContext() || 1622 RequireCompleteDeclContext(SS, DC)) 1623 return BuildDependentDeclRefExpr(SS, Name, NameLoc, &TemplateArgs); 1624 1625 bool MemberOfUnknownSpecialization; 1626 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1627 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false, 1628 MemberOfUnknownSpecialization); 1629 1630 if (R.isAmbiguous()) 1631 return ExprError(); 1632 1633 if (R.empty()) { 1634 Diag(NameLoc, diag::err_template_kw_refers_to_non_template) 1635 << Name << SS.getRange(); 1636 return ExprError(); 1637 } 1638 1639 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) { 1640 Diag(NameLoc, diag::err_template_kw_refers_to_class_template) 1641 << (NestedNameSpecifier*) SS.getScopeRep() << Name << SS.getRange(); 1642 Diag(Temp->getLocation(), diag::note_referenced_class_template); 1643 return ExprError(); 1644 } 1645 1646 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs); 1647} 1648 1649/// \brief Form a dependent template name. 1650/// 1651/// This action forms a dependent template name given the template 1652/// name and its (presumably dependent) scope specifier. For 1653/// example, given "MetaFun::template apply", the scope specifier \p 1654/// SS will be "MetaFun::", \p TemplateKWLoc contains the location 1655/// of the "template" keyword, and "apply" is the \p Name. 1656TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S, 1657 SourceLocation TemplateKWLoc, 1658 CXXScopeSpec &SS, 1659 UnqualifiedId &Name, 1660 TypeTy *ObjectType, 1661 bool EnteringContext, 1662 TemplateTy &Result) { 1663 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent() && 1664 !getLangOptions().CPlusPlus0x) 1665 Diag(TemplateKWLoc, diag::ext_template_outside_of_template) 1666 << FixItHint::CreateRemoval(TemplateKWLoc); 1667 1668 DeclContext *LookupCtx = 0; 1669 if (SS.isSet()) 1670 LookupCtx = computeDeclContext(SS, EnteringContext); 1671 if (!LookupCtx && ObjectType) 1672 LookupCtx = computeDeclContext(QualType::getFromOpaquePtr(ObjectType)); 1673 if (LookupCtx) { 1674 // C++0x [temp.names]p5: 1675 // If a name prefixed by the keyword template is not the name of 1676 // a template, the program is ill-formed. [Note: the keyword 1677 // template may not be applied to non-template members of class 1678 // templates. -end note ] [ Note: as is the case with the 1679 // typename prefix, the template prefix is allowed in cases 1680 // where it is not strictly necessary; i.e., when the 1681 // nested-name-specifier or the expression on the left of the -> 1682 // or . is not dependent on a template-parameter, or the use 1683 // does not appear in the scope of a template. -end note] 1684 // 1685 // Note: C++03 was more strict here, because it banned the use of 1686 // the "template" keyword prior to a template-name that was not a 1687 // dependent name. C++ DR468 relaxed this requirement (the 1688 // "template" keyword is now permitted). We follow the C++0x 1689 // rules, even in C++03 mode with a warning, retroactively applying the DR. 1690 bool MemberOfUnknownSpecialization; 1691 TemplateNameKind TNK = isTemplateName(0, SS, Name, ObjectType, 1692 EnteringContext, Result, 1693 MemberOfUnknownSpecialization); 1694 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() && 1695 isa<CXXRecordDecl>(LookupCtx) && 1696 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) { 1697 // This is a dependent template. Handle it below. 1698 } else if (TNK == TNK_Non_template) { 1699 Diag(Name.getSourceRange().getBegin(), 1700 diag::err_template_kw_refers_to_non_template) 1701 << GetNameFromUnqualifiedId(Name) 1702 << Name.getSourceRange() 1703 << TemplateKWLoc; 1704 return TNK_Non_template; 1705 } else { 1706 // We found something; return it. 1707 return TNK; 1708 } 1709 } 1710 1711 NestedNameSpecifier *Qualifier 1712 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1713 1714 switch (Name.getKind()) { 1715 case UnqualifiedId::IK_Identifier: 1716 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1717 Name.Identifier)); 1718 return TNK_Dependent_template_name; 1719 1720 case UnqualifiedId::IK_OperatorFunctionId: 1721 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1722 Name.OperatorFunctionId.Operator)); 1723 return TNK_Dependent_template_name; 1724 1725 case UnqualifiedId::IK_LiteralOperatorId: 1726 assert(false && "We don't support these; Parse shouldn't have allowed propagation"); 1727 1728 default: 1729 break; 1730 } 1731 1732 Diag(Name.getSourceRange().getBegin(), 1733 diag::err_template_kw_refers_to_non_template) 1734 << GetNameFromUnqualifiedId(Name) 1735 << Name.getSourceRange() 1736 << TemplateKWLoc; 1737 return TNK_Non_template; 1738} 1739 1740bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, 1741 const TemplateArgumentLoc &AL, 1742 TemplateArgumentListBuilder &Converted) { 1743 const TemplateArgument &Arg = AL.getArgument(); 1744 1745 // Check template type parameter. 1746 switch(Arg.getKind()) { 1747 case TemplateArgument::Type: 1748 // C++ [temp.arg.type]p1: 1749 // A template-argument for a template-parameter which is a 1750 // type shall be a type-id. 1751 break; 1752 case TemplateArgument::Template: { 1753 // We have a template type parameter but the template argument 1754 // is a template without any arguments. 1755 SourceRange SR = AL.getSourceRange(); 1756 TemplateName Name = Arg.getAsTemplate(); 1757 Diag(SR.getBegin(), diag::err_template_missing_args) 1758 << Name << SR; 1759 if (TemplateDecl *Decl = Name.getAsTemplateDecl()) 1760 Diag(Decl->getLocation(), diag::note_template_decl_here); 1761 1762 return true; 1763 } 1764 default: { 1765 // We have a template type parameter but the template argument 1766 // is not a type. 1767 SourceRange SR = AL.getSourceRange(); 1768 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; 1769 Diag(Param->getLocation(), diag::note_template_param_here); 1770 1771 return true; 1772 } 1773 } 1774 1775 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo())) 1776 return true; 1777 1778 // Add the converted template type argument. 1779 Converted.Append( 1780 TemplateArgument(Context.getCanonicalType(Arg.getAsType()))); 1781 return false; 1782} 1783 1784/// \brief Substitute template arguments into the default template argument for 1785/// the given template type parameter. 1786/// 1787/// \param SemaRef the semantic analysis object for which we are performing 1788/// the substitution. 1789/// 1790/// \param Template the template that we are synthesizing template arguments 1791/// for. 1792/// 1793/// \param TemplateLoc the location of the template name that started the 1794/// template-id we are checking. 1795/// 1796/// \param RAngleLoc the location of the right angle bracket ('>') that 1797/// terminates the template-id. 1798/// 1799/// \param Param the template template parameter whose default we are 1800/// substituting into. 1801/// 1802/// \param Converted the list of template arguments provided for template 1803/// parameters that precede \p Param in the template parameter list. 1804/// 1805/// \returns the substituted template argument, or NULL if an error occurred. 1806static TypeSourceInfo * 1807SubstDefaultTemplateArgument(Sema &SemaRef, 1808 TemplateDecl *Template, 1809 SourceLocation TemplateLoc, 1810 SourceLocation RAngleLoc, 1811 TemplateTypeParmDecl *Param, 1812 TemplateArgumentListBuilder &Converted) { 1813 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo(); 1814 1815 // If the argument type is dependent, instantiate it now based 1816 // on the previously-computed template arguments. 1817 if (ArgType->getType()->isDependentType()) { 1818 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1819 /*TakeArgs=*/false); 1820 1821 MultiLevelTemplateArgumentList AllTemplateArgs 1822 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1823 1824 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1825 Template, Converted.getFlatArguments(), 1826 Converted.flatSize(), 1827 SourceRange(TemplateLoc, RAngleLoc)); 1828 1829 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, 1830 Param->getDefaultArgumentLoc(), 1831 Param->getDeclName()); 1832 } 1833 1834 return ArgType; 1835} 1836 1837/// \brief Substitute template arguments into the default template argument for 1838/// the given non-type template parameter. 1839/// 1840/// \param SemaRef the semantic analysis object for which we are performing 1841/// the substitution. 1842/// 1843/// \param Template the template that we are synthesizing template arguments 1844/// for. 1845/// 1846/// \param TemplateLoc the location of the template name that started the 1847/// template-id we are checking. 1848/// 1849/// \param RAngleLoc the location of the right angle bracket ('>') that 1850/// terminates the template-id. 1851/// 1852/// \param Param the non-type template parameter whose default we are 1853/// substituting into. 1854/// 1855/// \param Converted the list of template arguments provided for template 1856/// parameters that precede \p Param in the template parameter list. 1857/// 1858/// \returns the substituted template argument, or NULL if an error occurred. 1859static Sema::OwningExprResult 1860SubstDefaultTemplateArgument(Sema &SemaRef, 1861 TemplateDecl *Template, 1862 SourceLocation TemplateLoc, 1863 SourceLocation RAngleLoc, 1864 NonTypeTemplateParmDecl *Param, 1865 TemplateArgumentListBuilder &Converted) { 1866 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1867 /*TakeArgs=*/false); 1868 1869 MultiLevelTemplateArgumentList AllTemplateArgs 1870 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1871 1872 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1873 Template, Converted.getFlatArguments(), 1874 Converted.flatSize(), 1875 SourceRange(TemplateLoc, RAngleLoc)); 1876 1877 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); 1878} 1879 1880/// \brief Substitute template arguments into the default template argument for 1881/// the given template template parameter. 1882/// 1883/// \param SemaRef the semantic analysis object for which we are performing 1884/// the substitution. 1885/// 1886/// \param Template the template that we are synthesizing template arguments 1887/// for. 1888/// 1889/// \param TemplateLoc the location of the template name that started the 1890/// template-id we are checking. 1891/// 1892/// \param RAngleLoc the location of the right angle bracket ('>') that 1893/// terminates the template-id. 1894/// 1895/// \param Param the template template parameter whose default we are 1896/// substituting into. 1897/// 1898/// \param Converted the list of template arguments provided for template 1899/// parameters that precede \p Param in the template parameter list. 1900/// 1901/// \returns the substituted template argument, or NULL if an error occurred. 1902static TemplateName 1903SubstDefaultTemplateArgument(Sema &SemaRef, 1904 TemplateDecl *Template, 1905 SourceLocation TemplateLoc, 1906 SourceLocation RAngleLoc, 1907 TemplateTemplateParmDecl *Param, 1908 TemplateArgumentListBuilder &Converted) { 1909 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1910 /*TakeArgs=*/false); 1911 1912 MultiLevelTemplateArgumentList AllTemplateArgs 1913 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1914 1915 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1916 Template, Converted.getFlatArguments(), 1917 Converted.flatSize(), 1918 SourceRange(TemplateLoc, RAngleLoc)); 1919 1920 return SemaRef.SubstTemplateName( 1921 Param->getDefaultArgument().getArgument().getAsTemplate(), 1922 Param->getDefaultArgument().getTemplateNameLoc(), 1923 AllTemplateArgs); 1924} 1925 1926/// \brief If the given template parameter has a default template 1927/// argument, substitute into that default template argument and 1928/// return the corresponding template argument. 1929TemplateArgumentLoc 1930Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template, 1931 SourceLocation TemplateLoc, 1932 SourceLocation RAngleLoc, 1933 Decl *Param, 1934 TemplateArgumentListBuilder &Converted) { 1935 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) { 1936 if (!TypeParm->hasDefaultArgument()) 1937 return TemplateArgumentLoc(); 1938 1939 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template, 1940 TemplateLoc, 1941 RAngleLoc, 1942 TypeParm, 1943 Converted); 1944 if (DI) 1945 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI); 1946 1947 return TemplateArgumentLoc(); 1948 } 1949 1950 if (NonTypeTemplateParmDecl *NonTypeParm 1951 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1952 if (!NonTypeParm->hasDefaultArgument()) 1953 return TemplateArgumentLoc(); 1954 1955 OwningExprResult Arg = SubstDefaultTemplateArgument(*this, Template, 1956 TemplateLoc, 1957 RAngleLoc, 1958 NonTypeParm, 1959 Converted); 1960 if (Arg.isInvalid()) 1961 return TemplateArgumentLoc(); 1962 1963 Expr *ArgE = Arg.takeAs<Expr>(); 1964 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE); 1965 } 1966 1967 TemplateTemplateParmDecl *TempTempParm 1968 = cast<TemplateTemplateParmDecl>(Param); 1969 if (!TempTempParm->hasDefaultArgument()) 1970 return TemplateArgumentLoc(); 1971 1972 TemplateName TName = SubstDefaultTemplateArgument(*this, Template, 1973 TemplateLoc, 1974 RAngleLoc, 1975 TempTempParm, 1976 Converted); 1977 if (TName.isNull()) 1978 return TemplateArgumentLoc(); 1979 1980 return TemplateArgumentLoc(TemplateArgument(TName), 1981 TempTempParm->getDefaultArgument().getTemplateQualifierRange(), 1982 TempTempParm->getDefaultArgument().getTemplateNameLoc()); 1983} 1984 1985/// \brief Check that the given template argument corresponds to the given 1986/// template parameter. 1987bool Sema::CheckTemplateArgument(NamedDecl *Param, 1988 const TemplateArgumentLoc &Arg, 1989 TemplateDecl *Template, 1990 SourceLocation TemplateLoc, 1991 SourceLocation RAngleLoc, 1992 TemplateArgumentListBuilder &Converted, 1993 CheckTemplateArgumentKind CTAK) { 1994 // Check template type parameters. 1995 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) 1996 return CheckTemplateTypeArgument(TTP, Arg, Converted); 1997 1998 // Check non-type template parameters. 1999 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { 2000 // Do substitution on the type of the non-type template parameter 2001 // with the template arguments we've seen thus far. 2002 QualType NTTPType = NTTP->getType(); 2003 if (NTTPType->isDependentType()) { 2004 // Do substitution on the type of the non-type template parameter. 2005 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2006 NTTP, Converted.getFlatArguments(), 2007 Converted.flatSize(), 2008 SourceRange(TemplateLoc, RAngleLoc)); 2009 2010 TemplateArgumentList TemplateArgs(Context, Converted, 2011 /*TakeArgs=*/false); 2012 NTTPType = SubstType(NTTPType, 2013 MultiLevelTemplateArgumentList(TemplateArgs), 2014 NTTP->getLocation(), 2015 NTTP->getDeclName()); 2016 // If that worked, check the non-type template parameter type 2017 // for validity. 2018 if (!NTTPType.isNull()) 2019 NTTPType = CheckNonTypeTemplateParameterType(NTTPType, 2020 NTTP->getLocation()); 2021 if (NTTPType.isNull()) 2022 return true; 2023 } 2024 2025 switch (Arg.getArgument().getKind()) { 2026 case TemplateArgument::Null: 2027 assert(false && "Should never see a NULL template argument here"); 2028 return true; 2029 2030 case TemplateArgument::Expression: { 2031 Expr *E = Arg.getArgument().getAsExpr(); 2032 TemplateArgument Result; 2033 if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK)) 2034 return true; 2035 2036 Converted.Append(Result); 2037 break; 2038 } 2039 2040 case TemplateArgument::Declaration: 2041 case TemplateArgument::Integral: 2042 // We've already checked this template argument, so just copy 2043 // it to the list of converted arguments. 2044 Converted.Append(Arg.getArgument()); 2045 break; 2046 2047 case TemplateArgument::Template: 2048 // We were given a template template argument. It may not be ill-formed; 2049 // see below. 2050 if (DependentTemplateName *DTN 2051 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) { 2052 // We have a template argument such as \c T::template X, which we 2053 // parsed as a template template argument. However, since we now 2054 // know that we need a non-type template argument, convert this 2055 // template name into an expression. 2056 Expr *E = DependentScopeDeclRefExpr::Create(Context, 2057 DTN->getQualifier(), 2058 Arg.getTemplateQualifierRange(), 2059 DTN->getIdentifier(), 2060 Arg.getTemplateNameLoc()); 2061 2062 TemplateArgument Result; 2063 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 2064 return true; 2065 2066 Converted.Append(Result); 2067 break; 2068 } 2069 2070 // We have a template argument that actually does refer to a class 2071 // template, template alias, or template template parameter, and 2072 // therefore cannot be a non-type template argument. 2073 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) 2074 << Arg.getSourceRange(); 2075 2076 Diag(Param->getLocation(), diag::note_template_param_here); 2077 return true; 2078 2079 case TemplateArgument::Type: { 2080 // We have a non-type template parameter but the template 2081 // argument is a type. 2082 2083 // C++ [temp.arg]p2: 2084 // In a template-argument, an ambiguity between a type-id and 2085 // an expression is resolved to a type-id, regardless of the 2086 // form of the corresponding template-parameter. 2087 // 2088 // We warn specifically about this case, since it can be rather 2089 // confusing for users. 2090 QualType T = Arg.getArgument().getAsType(); 2091 SourceRange SR = Arg.getSourceRange(); 2092 if (T->isFunctionType()) 2093 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; 2094 else 2095 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; 2096 Diag(Param->getLocation(), diag::note_template_param_here); 2097 return true; 2098 } 2099 2100 case TemplateArgument::Pack: 2101 llvm_unreachable("Caller must expand template argument packs"); 2102 break; 2103 } 2104 2105 return false; 2106 } 2107 2108 2109 // Check template template parameters. 2110 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); 2111 2112 // Substitute into the template parameter list of the template 2113 // template parameter, since previously-supplied template arguments 2114 // may appear within the template template parameter. 2115 { 2116 // Set up a template instantiation context. 2117 LocalInstantiationScope Scope(*this); 2118 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2119 TempParm, Converted.getFlatArguments(), 2120 Converted.flatSize(), 2121 SourceRange(TemplateLoc, RAngleLoc)); 2122 2123 TemplateArgumentList TemplateArgs(Context, Converted, 2124 /*TakeArgs=*/false); 2125 TempParm = cast_or_null<TemplateTemplateParmDecl>( 2126 SubstDecl(TempParm, CurContext, 2127 MultiLevelTemplateArgumentList(TemplateArgs))); 2128 if (!TempParm) 2129 return true; 2130 2131 // FIXME: TempParam is leaked. 2132 } 2133 2134 switch (Arg.getArgument().getKind()) { 2135 case TemplateArgument::Null: 2136 assert(false && "Should never see a NULL template argument here"); 2137 return true; 2138 2139 case TemplateArgument::Template: 2140 if (CheckTemplateArgument(TempParm, Arg)) 2141 return true; 2142 2143 Converted.Append(Arg.getArgument()); 2144 break; 2145 2146 case TemplateArgument::Expression: 2147 case TemplateArgument::Type: 2148 // We have a template template parameter but the template 2149 // argument does not refer to a template. 2150 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template); 2151 return true; 2152 2153 case TemplateArgument::Declaration: 2154 llvm_unreachable( 2155 "Declaration argument with template template parameter"); 2156 break; 2157 case TemplateArgument::Integral: 2158 llvm_unreachable( 2159 "Integral argument with template template parameter"); 2160 break; 2161 2162 case TemplateArgument::Pack: 2163 llvm_unreachable("Caller must expand template argument packs"); 2164 break; 2165 } 2166 2167 return false; 2168} 2169 2170/// \brief Check that the given template argument list is well-formed 2171/// for specializing the given template. 2172bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, 2173 SourceLocation TemplateLoc, 2174 const TemplateArgumentListInfo &TemplateArgs, 2175 bool PartialTemplateArgs, 2176 TemplateArgumentListBuilder &Converted) { 2177 TemplateParameterList *Params = Template->getTemplateParameters(); 2178 unsigned NumParams = Params->size(); 2179 unsigned NumArgs = TemplateArgs.size(); 2180 bool Invalid = false; 2181 2182 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc(); 2183 2184 bool HasParameterPack = 2185 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); 2186 2187 if ((NumArgs > NumParams && !HasParameterPack) || 2188 (NumArgs < Params->getMinRequiredArguments() && 2189 !PartialTemplateArgs)) { 2190 // FIXME: point at either the first arg beyond what we can handle, 2191 // or the '>', depending on whether we have too many or too few 2192 // arguments. 2193 SourceRange Range; 2194 if (NumArgs > NumParams) 2195 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc); 2196 Diag(TemplateLoc, diag::err_template_arg_list_different_arity) 2197 << (NumArgs > NumParams) 2198 << (isa<ClassTemplateDecl>(Template)? 0 : 2199 isa<FunctionTemplateDecl>(Template)? 1 : 2200 isa<TemplateTemplateParmDecl>(Template)? 2 : 3) 2201 << Template << Range; 2202 Diag(Template->getLocation(), diag::note_template_decl_here) 2203 << Params->getSourceRange(); 2204 Invalid = true; 2205 } 2206 2207 // C++ [temp.arg]p1: 2208 // [...] The type and form of each template-argument specified in 2209 // a template-id shall match the type and form specified for the 2210 // corresponding parameter declared by the template in its 2211 // template-parameter-list. 2212 unsigned ArgIdx = 0; 2213 for (TemplateParameterList::iterator Param = Params->begin(), 2214 ParamEnd = Params->end(); 2215 Param != ParamEnd; ++Param, ++ArgIdx) { 2216 if (ArgIdx > NumArgs && PartialTemplateArgs) 2217 break; 2218 2219 // If we have a template parameter pack, check every remaining template 2220 // argument against that template parameter pack. 2221 if ((*Param)->isTemplateParameterPack()) { 2222 Converted.BeginPack(); 2223 for (; ArgIdx < NumArgs; ++ArgIdx) { 2224 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2225 TemplateLoc, RAngleLoc, Converted)) { 2226 Invalid = true; 2227 break; 2228 } 2229 } 2230 Converted.EndPack(); 2231 continue; 2232 } 2233 2234 if (ArgIdx < NumArgs) { 2235 // Check the template argument we were given. 2236 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2237 TemplateLoc, RAngleLoc, Converted)) 2238 return true; 2239 2240 continue; 2241 } 2242 2243 // We have a default template argument that we will use. 2244 TemplateArgumentLoc Arg; 2245 2246 // Retrieve the default template argument from the template 2247 // parameter. For each kind of template parameter, we substitute the 2248 // template arguments provided thus far and any "outer" template arguments 2249 // (when the template parameter was part of a nested template) into 2250 // the default argument. 2251 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { 2252 if (!TTP->hasDefaultArgument()) { 2253 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2254 break; 2255 } 2256 2257 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this, 2258 Template, 2259 TemplateLoc, 2260 RAngleLoc, 2261 TTP, 2262 Converted); 2263 if (!ArgType) 2264 return true; 2265 2266 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), 2267 ArgType); 2268 } else if (NonTypeTemplateParmDecl *NTTP 2269 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { 2270 if (!NTTP->hasDefaultArgument()) { 2271 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2272 break; 2273 } 2274 2275 Sema::OwningExprResult E = SubstDefaultTemplateArgument(*this, Template, 2276 TemplateLoc, 2277 RAngleLoc, 2278 NTTP, 2279 Converted); 2280 if (E.isInvalid()) 2281 return true; 2282 2283 Expr *Ex = E.takeAs<Expr>(); 2284 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); 2285 } else { 2286 TemplateTemplateParmDecl *TempParm 2287 = cast<TemplateTemplateParmDecl>(*Param); 2288 2289 if (!TempParm->hasDefaultArgument()) { 2290 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2291 break; 2292 } 2293 2294 TemplateName Name = SubstDefaultTemplateArgument(*this, Template, 2295 TemplateLoc, 2296 RAngleLoc, 2297 TempParm, 2298 Converted); 2299 if (Name.isNull()) 2300 return true; 2301 2302 Arg = TemplateArgumentLoc(TemplateArgument(Name), 2303 TempParm->getDefaultArgument().getTemplateQualifierRange(), 2304 TempParm->getDefaultArgument().getTemplateNameLoc()); 2305 } 2306 2307 // Introduce an instantiation record that describes where we are using 2308 // the default template argument. 2309 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, 2310 Converted.getFlatArguments(), 2311 Converted.flatSize(), 2312 SourceRange(TemplateLoc, RAngleLoc)); 2313 2314 // Check the default template argument. 2315 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, 2316 RAngleLoc, Converted)) 2317 return true; 2318 } 2319 2320 return Invalid; 2321} 2322 2323/// \brief Check a template argument against its corresponding 2324/// template type parameter. 2325/// 2326/// This routine implements the semantics of C++ [temp.arg.type]. It 2327/// returns true if an error occurred, and false otherwise. 2328bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, 2329 TypeSourceInfo *ArgInfo) { 2330 assert(ArgInfo && "invalid TypeSourceInfo"); 2331 QualType Arg = ArgInfo->getType(); 2332 2333 // C++ [temp.arg.type]p2: 2334 // A local type, a type with no linkage, an unnamed type or a type 2335 // compounded from any of these types shall not be used as a 2336 // template-argument for a template type-parameter. 2337 // 2338 // FIXME: Perform the unnamed type check. 2339 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); 2340 const TagType *Tag = 0; 2341 if (const EnumType *EnumT = Arg->getAs<EnumType>()) 2342 Tag = EnumT; 2343 else if (const RecordType *RecordT = Arg->getAs<RecordType>()) 2344 Tag = RecordT; 2345 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) { 2346 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); 2347 return Diag(SR.getBegin(), diag::err_template_arg_local_type) 2348 << QualType(Tag, 0) << SR; 2349 } else if (Tag && !Tag->getDecl()->getDeclName() && 2350 !Tag->getDecl()->getTypedefForAnonDecl()) { 2351 Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR; 2352 Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here); 2353 return true; 2354 } else if (Arg->isVariablyModifiedType()) { 2355 Diag(SR.getBegin(), diag::err_variably_modified_template_arg) 2356 << Arg; 2357 return true; 2358 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) { 2359 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR; 2360 } 2361 2362 return false; 2363} 2364 2365/// \brief Checks whether the given template argument is the address 2366/// of an object or function according to C++ [temp.arg.nontype]p1. 2367static bool 2368CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S, 2369 NonTypeTemplateParmDecl *Param, 2370 QualType ParamType, 2371 Expr *ArgIn, 2372 TemplateArgument &Converted) { 2373 bool Invalid = false; 2374 Expr *Arg = ArgIn; 2375 QualType ArgType = Arg->getType(); 2376 2377 // See through any implicit casts we added to fix the type. 2378 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2379 Arg = Cast->getSubExpr(); 2380 2381 // C++ [temp.arg.nontype]p1: 2382 // 2383 // A template-argument for a non-type, non-template 2384 // template-parameter shall be one of: [...] 2385 // 2386 // -- the address of an object or function with external 2387 // linkage, including function templates and function 2388 // template-ids but excluding non-static class members, 2389 // expressed as & id-expression where the & is optional if 2390 // the name refers to a function or array, or if the 2391 // corresponding template-parameter is a reference; or 2392 DeclRefExpr *DRE = 0; 2393 2394 // Ignore (and complain about) any excess parentheses. 2395 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2396 if (!Invalid) { 2397 S.Diag(Arg->getSourceRange().getBegin(), 2398 diag::err_template_arg_extra_parens) 2399 << Arg->getSourceRange(); 2400 Invalid = true; 2401 } 2402 2403 Arg = Parens->getSubExpr(); 2404 } 2405 2406 bool AddressTaken = false; 2407 SourceLocation AddrOpLoc; 2408 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2409 if (UnOp->getOpcode() == UnaryOperator::AddrOf) { 2410 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2411 AddressTaken = true; 2412 AddrOpLoc = UnOp->getOperatorLoc(); 2413 } 2414 } else 2415 DRE = dyn_cast<DeclRefExpr>(Arg); 2416 2417 if (!DRE) { 2418 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref) 2419 << Arg->getSourceRange(); 2420 S.Diag(Param->getLocation(), diag::note_template_param_here); 2421 return true; 2422 } 2423 2424 // Stop checking the precise nature of the argument if it is value dependent, 2425 // it should be checked when instantiated. 2426 if (Arg->isValueDependent()) { 2427 Converted = TemplateArgument(ArgIn->Retain()); 2428 return false; 2429 } 2430 2431 if (!isa<ValueDecl>(DRE->getDecl())) { 2432 S.Diag(Arg->getSourceRange().getBegin(), 2433 diag::err_template_arg_not_object_or_func_form) 2434 << Arg->getSourceRange(); 2435 S.Diag(Param->getLocation(), diag::note_template_param_here); 2436 return true; 2437 } 2438 2439 NamedDecl *Entity = 0; 2440 2441 // Cannot refer to non-static data members 2442 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) { 2443 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field) 2444 << Field << Arg->getSourceRange(); 2445 S.Diag(Param->getLocation(), diag::note_template_param_here); 2446 return true; 2447 } 2448 2449 // Cannot refer to non-static member functions 2450 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl())) 2451 if (!Method->isStatic()) { 2452 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method) 2453 << Method << Arg->getSourceRange(); 2454 S.Diag(Param->getLocation(), diag::note_template_param_here); 2455 return true; 2456 } 2457 2458 // Functions must have external linkage. 2459 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) { 2460 if (!isExternalLinkage(Func->getLinkage())) { 2461 S.Diag(Arg->getSourceRange().getBegin(), 2462 diag::err_template_arg_function_not_extern) 2463 << Func << Arg->getSourceRange(); 2464 S.Diag(Func->getLocation(), diag::note_template_arg_internal_object) 2465 << true; 2466 return true; 2467 } 2468 2469 // Okay: we've named a function with external linkage. 2470 Entity = Func; 2471 2472 // If the template parameter has pointer type, the function decays. 2473 if (ParamType->isPointerType() && !AddressTaken) 2474 ArgType = S.Context.getPointerType(Func->getType()); 2475 else if (AddressTaken && ParamType->isReferenceType()) { 2476 // If we originally had an address-of operator, but the 2477 // parameter has reference type, complain and (if things look 2478 // like they will work) drop the address-of operator. 2479 if (!S.Context.hasSameUnqualifiedType(Func->getType(), 2480 ParamType.getNonReferenceType())) { 2481 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2482 << ParamType; 2483 S.Diag(Param->getLocation(), diag::note_template_param_here); 2484 return true; 2485 } 2486 2487 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2488 << ParamType 2489 << FixItHint::CreateRemoval(AddrOpLoc); 2490 S.Diag(Param->getLocation(), diag::note_template_param_here); 2491 2492 ArgType = Func->getType(); 2493 } 2494 } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 2495 if (!isExternalLinkage(Var->getLinkage())) { 2496 S.Diag(Arg->getSourceRange().getBegin(), 2497 diag::err_template_arg_object_not_extern) 2498 << Var << Arg->getSourceRange(); 2499 S.Diag(Var->getLocation(), diag::note_template_arg_internal_object) 2500 << true; 2501 return true; 2502 } 2503 2504 // A value of reference type is not an object. 2505 if (Var->getType()->isReferenceType()) { 2506 S.Diag(Arg->getSourceRange().getBegin(), 2507 diag::err_template_arg_reference_var) 2508 << Var->getType() << Arg->getSourceRange(); 2509 S.Diag(Param->getLocation(), diag::note_template_param_here); 2510 return true; 2511 } 2512 2513 // Okay: we've named an object with external linkage 2514 Entity = Var; 2515 2516 // If the template parameter has pointer type, we must have taken 2517 // the address of this object. 2518 if (ParamType->isReferenceType()) { 2519 if (AddressTaken) { 2520 // If we originally had an address-of operator, but the 2521 // parameter has reference type, complain and (if things look 2522 // like they will work) drop the address-of operator. 2523 if (!S.Context.hasSameUnqualifiedType(Var->getType(), 2524 ParamType.getNonReferenceType())) { 2525 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2526 << ParamType; 2527 S.Diag(Param->getLocation(), diag::note_template_param_here); 2528 return true; 2529 } 2530 2531 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2532 << ParamType 2533 << FixItHint::CreateRemoval(AddrOpLoc); 2534 S.Diag(Param->getLocation(), diag::note_template_param_here); 2535 2536 ArgType = Var->getType(); 2537 } 2538 } else if (!AddressTaken && ParamType->isPointerType()) { 2539 if (Var->getType()->isArrayType()) { 2540 // Array-to-pointer decay. 2541 ArgType = S.Context.getArrayDecayedType(Var->getType()); 2542 } else { 2543 // If the template parameter has pointer type but the address of 2544 // this object was not taken, complain and (possibly) recover by 2545 // taking the address of the entity. 2546 ArgType = S.Context.getPointerType(Var->getType()); 2547 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) { 2548 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2549 << ParamType; 2550 S.Diag(Param->getLocation(), diag::note_template_param_here); 2551 return true; 2552 } 2553 2554 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2555 << ParamType 2556 << FixItHint::CreateInsertion(Arg->getLocStart(), "&"); 2557 2558 S.Diag(Param->getLocation(), diag::note_template_param_here); 2559 } 2560 } 2561 } else { 2562 // We found something else, but we don't know specifically what it is. 2563 S.Diag(Arg->getSourceRange().getBegin(), 2564 diag::err_template_arg_not_object_or_func) 2565 << Arg->getSourceRange(); 2566 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); 2567 return true; 2568 } 2569 2570 if (ParamType->isPointerType() && 2571 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() && 2572 S.IsQualificationConversion(ArgType, ParamType)) { 2573 // For pointer-to-object types, qualification conversions are 2574 // permitted. 2575 } else { 2576 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) { 2577 if (!ParamRef->getPointeeType()->isFunctionType()) { 2578 // C++ [temp.arg.nontype]p5b3: 2579 // For a non-type template-parameter of type reference to 2580 // object, no conversions apply. The type referred to by the 2581 // reference may be more cv-qualified than the (otherwise 2582 // identical) type of the template- argument. The 2583 // template-parameter is bound directly to the 2584 // template-argument, which shall be an lvalue. 2585 2586 // FIXME: Other qualifiers? 2587 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers(); 2588 unsigned ArgQuals = ArgType.getCVRQualifiers(); 2589 2590 if ((ParamQuals | ArgQuals) != ParamQuals) { 2591 S.Diag(Arg->getSourceRange().getBegin(), 2592 diag::err_template_arg_ref_bind_ignores_quals) 2593 << ParamType << Arg->getType() 2594 << Arg->getSourceRange(); 2595 S.Diag(Param->getLocation(), diag::note_template_param_here); 2596 return true; 2597 } 2598 } 2599 } 2600 2601 // At this point, the template argument refers to an object or 2602 // function with external linkage. We now need to check whether the 2603 // argument and parameter types are compatible. 2604 if (!S.Context.hasSameUnqualifiedType(ArgType, 2605 ParamType.getNonReferenceType())) { 2606 // We can't perform this conversion or binding. 2607 if (ParamType->isReferenceType()) 2608 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind) 2609 << ParamType << Arg->getType() << Arg->getSourceRange(); 2610 else 2611 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible) 2612 << Arg->getType() << ParamType << Arg->getSourceRange(); 2613 S.Diag(Param->getLocation(), diag::note_template_param_here); 2614 return true; 2615 } 2616 } 2617 2618 // Create the template argument. 2619 Converted = TemplateArgument(Entity->getCanonicalDecl()); 2620 S.MarkDeclarationReferenced(Arg->getLocStart(), Entity); 2621 return false; 2622} 2623 2624/// \brief Checks whether the given template argument is a pointer to 2625/// member constant according to C++ [temp.arg.nontype]p1. 2626bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, 2627 TemplateArgument &Converted) { 2628 bool Invalid = false; 2629 2630 // See through any implicit casts we added to fix the type. 2631 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2632 Arg = Cast->getSubExpr(); 2633 2634 // C++ [temp.arg.nontype]p1: 2635 // 2636 // A template-argument for a non-type, non-template 2637 // template-parameter shall be one of: [...] 2638 // 2639 // -- a pointer to member expressed as described in 5.3.1. 2640 DeclRefExpr *DRE = 0; 2641 2642 // Ignore (and complain about) any excess parentheses. 2643 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2644 if (!Invalid) { 2645 Diag(Arg->getSourceRange().getBegin(), 2646 diag::err_template_arg_extra_parens) 2647 << Arg->getSourceRange(); 2648 Invalid = true; 2649 } 2650 2651 Arg = Parens->getSubExpr(); 2652 } 2653 2654 // A pointer-to-member constant written &Class::member. 2655 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2656 if (UnOp->getOpcode() == UnaryOperator::AddrOf) { 2657 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2658 if (DRE && !DRE->getQualifier()) 2659 DRE = 0; 2660 } 2661 } 2662 // A constant of pointer-to-member type. 2663 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { 2664 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { 2665 if (VD->getType()->isMemberPointerType()) { 2666 if (isa<NonTypeTemplateParmDecl>(VD) || 2667 (isa<VarDecl>(VD) && 2668 Context.getCanonicalType(VD->getType()).isConstQualified())) { 2669 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2670 Converted = TemplateArgument(Arg->Retain()); 2671 else 2672 Converted = TemplateArgument(VD->getCanonicalDecl()); 2673 return Invalid; 2674 } 2675 } 2676 } 2677 2678 DRE = 0; 2679 } 2680 2681 if (!DRE) 2682 return Diag(Arg->getSourceRange().getBegin(), 2683 diag::err_template_arg_not_pointer_to_member_form) 2684 << Arg->getSourceRange(); 2685 2686 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { 2687 assert((isa<FieldDecl>(DRE->getDecl()) || 2688 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && 2689 "Only non-static member pointers can make it here"); 2690 2691 // Okay: this is the address of a non-static member, and therefore 2692 // a member pointer constant. 2693 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2694 Converted = TemplateArgument(Arg->Retain()); 2695 else 2696 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); 2697 return Invalid; 2698 } 2699 2700 // We found something else, but we don't know specifically what it is. 2701 Diag(Arg->getSourceRange().getBegin(), 2702 diag::err_template_arg_not_pointer_to_member_form) 2703 << Arg->getSourceRange(); 2704 Diag(DRE->getDecl()->getLocation(), 2705 diag::note_template_arg_refers_here); 2706 return true; 2707} 2708 2709/// \brief Check a template argument against its corresponding 2710/// non-type template parameter. 2711/// 2712/// This routine implements the semantics of C++ [temp.arg.nontype]. 2713/// It returns true if an error occurred, and false otherwise. \p 2714/// InstantiatedParamType is the type of the non-type template 2715/// parameter after it has been instantiated. 2716/// 2717/// If no error was detected, Converted receives the converted template argument. 2718bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, 2719 QualType InstantiatedParamType, Expr *&Arg, 2720 TemplateArgument &Converted, 2721 CheckTemplateArgumentKind CTAK) { 2722 SourceLocation StartLoc = Arg->getSourceRange().getBegin(); 2723 2724 // If either the parameter has a dependent type or the argument is 2725 // type-dependent, there's nothing we can check now. 2726 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { 2727 // FIXME: Produce a cloned, canonical expression? 2728 Converted = TemplateArgument(Arg); 2729 return false; 2730 } 2731 2732 // C++ [temp.arg.nontype]p5: 2733 // The following conversions are performed on each expression used 2734 // as a non-type template-argument. If a non-type 2735 // template-argument cannot be converted to the type of the 2736 // corresponding template-parameter then the program is 2737 // ill-formed. 2738 // 2739 // -- for a non-type template-parameter of integral or 2740 // enumeration type, integral promotions (4.5) and integral 2741 // conversions (4.7) are applied. 2742 QualType ParamType = InstantiatedParamType; 2743 QualType ArgType = Arg->getType(); 2744 if (ParamType->isIntegralOrEnumerationType()) { 2745 // C++ [temp.arg.nontype]p1: 2746 // A template-argument for a non-type, non-template 2747 // template-parameter shall be one of: 2748 // 2749 // -- an integral constant-expression of integral or enumeration 2750 // type; or 2751 // -- the name of a non-type template-parameter; or 2752 SourceLocation NonConstantLoc; 2753 llvm::APSInt Value; 2754 if (!ArgType->isIntegralOrEnumerationType()) { 2755 Diag(Arg->getSourceRange().getBegin(), 2756 diag::err_template_arg_not_integral_or_enumeral) 2757 << ArgType << Arg->getSourceRange(); 2758 Diag(Param->getLocation(), diag::note_template_param_here); 2759 return true; 2760 } else if (!Arg->isValueDependent() && 2761 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) { 2762 Diag(NonConstantLoc, diag::err_template_arg_not_ice) 2763 << ArgType << Arg->getSourceRange(); 2764 return true; 2765 } 2766 2767 // From here on out, all we care about are the unqualified forms 2768 // of the parameter and argument types. 2769 ParamType = ParamType.getUnqualifiedType(); 2770 ArgType = ArgType.getUnqualifiedType(); 2771 2772 // Try to convert the argument to the parameter's type. 2773 if (Context.hasSameType(ParamType, ArgType)) { 2774 // Okay: no conversion necessary 2775 } else if (CTAK == CTAK_Deduced) { 2776 // C++ [temp.deduct.type]p17: 2777 // If, in the declaration of a function template with a non-type 2778 // template-parameter, the non-type template- parameter is used 2779 // in an expression in the function parameter-list and, if the 2780 // corresponding template-argument is deduced, the 2781 // template-argument type shall match the type of the 2782 // template-parameter exactly, except that a template-argument 2783 // deduced from an array bound may be of any integral type. 2784 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch) 2785 << ArgType << ParamType; 2786 Diag(Param->getLocation(), diag::note_template_param_here); 2787 return true; 2788 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || 2789 !ParamType->isEnumeralType()) { 2790 // This is an integral promotion or conversion. 2791 ImpCastExprToType(Arg, ParamType, CastExpr::CK_IntegralCast); 2792 } else { 2793 // We can't perform this conversion. 2794 Diag(Arg->getSourceRange().getBegin(), 2795 diag::err_template_arg_not_convertible) 2796 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2797 Diag(Param->getLocation(), diag::note_template_param_here); 2798 return true; 2799 } 2800 2801 QualType IntegerType = Context.getCanonicalType(ParamType); 2802 if (const EnumType *Enum = IntegerType->getAs<EnumType>()) 2803 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); 2804 2805 if (!Arg->isValueDependent()) { 2806 llvm::APSInt OldValue = Value; 2807 2808 // Coerce the template argument's value to the value it will have 2809 // based on the template parameter's type. 2810 unsigned AllowedBits = Context.getTypeSize(IntegerType); 2811 if (Value.getBitWidth() != AllowedBits) 2812 Value.extOrTrunc(AllowedBits); 2813 Value.setIsSigned(IntegerType->isSignedIntegerType()); 2814 2815 // Complain if an unsigned parameter received a negative value. 2816 if (IntegerType->isUnsignedIntegerType() 2817 && (OldValue.isSigned() && OldValue.isNegative())) { 2818 Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative) 2819 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2820 << Arg->getSourceRange(); 2821 Diag(Param->getLocation(), diag::note_template_param_here); 2822 } 2823 2824 // Complain if we overflowed the template parameter's type. 2825 unsigned RequiredBits; 2826 if (IntegerType->isUnsignedIntegerType()) 2827 RequiredBits = OldValue.getActiveBits(); 2828 else if (OldValue.isUnsigned()) 2829 RequiredBits = OldValue.getActiveBits() + 1; 2830 else 2831 RequiredBits = OldValue.getMinSignedBits(); 2832 if (RequiredBits > AllowedBits) { 2833 Diag(Arg->getSourceRange().getBegin(), 2834 diag::warn_template_arg_too_large) 2835 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2836 << Arg->getSourceRange(); 2837 Diag(Param->getLocation(), diag::note_template_param_here); 2838 } 2839 } 2840 2841 // Add the value of this argument to the list of converted 2842 // arguments. We use the bitwidth and signedness of the template 2843 // parameter. 2844 if (Arg->isValueDependent()) { 2845 // The argument is value-dependent. Create a new 2846 // TemplateArgument with the converted expression. 2847 Converted = TemplateArgument(Arg); 2848 return false; 2849 } 2850 2851 Converted = TemplateArgument(Value, 2852 ParamType->isEnumeralType() ? ParamType 2853 : IntegerType); 2854 return false; 2855 } 2856 2857 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction 2858 2859 // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion 2860 // from a template argument of type std::nullptr_t to a non-type 2861 // template parameter of type pointer to object, pointer to 2862 // function, or pointer-to-member, respectively. 2863 if (ArgType->isNullPtrType() && 2864 (ParamType->isPointerType() || ParamType->isMemberPointerType())) { 2865 Converted = TemplateArgument((NamedDecl *)0); 2866 return false; 2867 } 2868 2869 // Handle pointer-to-function, reference-to-function, and 2870 // pointer-to-member-function all in (roughly) the same way. 2871 if (// -- For a non-type template-parameter of type pointer to 2872 // function, only the function-to-pointer conversion (4.3) is 2873 // applied. If the template-argument represents a set of 2874 // overloaded functions (or a pointer to such), the matching 2875 // function is selected from the set (13.4). 2876 (ParamType->isPointerType() && 2877 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || 2878 // -- For a non-type template-parameter of type reference to 2879 // function, no conversions apply. If the template-argument 2880 // represents a set of overloaded functions, the matching 2881 // function is selected from the set (13.4). 2882 (ParamType->isReferenceType() && 2883 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || 2884 // -- For a non-type template-parameter of type pointer to 2885 // member function, no conversions apply. If the 2886 // template-argument represents a set of overloaded member 2887 // functions, the matching member function is selected from 2888 // the set (13.4). 2889 (ParamType->isMemberPointerType() && 2890 ParamType->getAs<MemberPointerType>()->getPointeeType() 2891 ->isFunctionType())) { 2892 2893 if (Arg->getType() == Context.OverloadTy) { 2894 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType, 2895 true, 2896 FoundResult)) { 2897 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2898 return true; 2899 2900 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2901 ArgType = Arg->getType(); 2902 } else 2903 return true; 2904 } 2905 2906 if (!ParamType->isMemberPointerType()) 2907 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2908 ParamType, 2909 Arg, Converted); 2910 2911 if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType())) { 2912 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp, 2913 Arg->isLvalue(Context) == Expr::LV_Valid); 2914 } else if (!Context.hasSameUnqualifiedType(ArgType, 2915 ParamType.getNonReferenceType())) { 2916 // We can't perform this conversion. 2917 Diag(Arg->getSourceRange().getBegin(), 2918 diag::err_template_arg_not_convertible) 2919 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2920 Diag(Param->getLocation(), diag::note_template_param_here); 2921 return true; 2922 } 2923 2924 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2925 } 2926 2927 if (ParamType->isPointerType()) { 2928 // -- for a non-type template-parameter of type pointer to 2929 // object, qualification conversions (4.4) and the 2930 // array-to-pointer conversion (4.2) are applied. 2931 // C++0x also allows a value of std::nullptr_t. 2932 assert(ParamType->getAs<PointerType>()->getPointeeType()->isObjectType() && 2933 "Only object pointers allowed here"); 2934 2935 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2936 ParamType, 2937 Arg, Converted); 2938 } 2939 2940 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { 2941 // -- For a non-type template-parameter of type reference to 2942 // object, no conversions apply. The type referred to by the 2943 // reference may be more cv-qualified than the (otherwise 2944 // identical) type of the template-argument. The 2945 // template-parameter is bound directly to the 2946 // template-argument, which must be an lvalue. 2947 assert(ParamRefType->getPointeeType()->isObjectType() && 2948 "Only object references allowed here"); 2949 2950 if (Arg->getType() == Context.OverloadTy) { 2951 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, 2952 ParamRefType->getPointeeType(), 2953 true, 2954 FoundResult)) { 2955 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2956 return true; 2957 2958 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2959 ArgType = Arg->getType(); 2960 } else 2961 return true; 2962 } 2963 2964 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2965 ParamType, 2966 Arg, Converted); 2967 } 2968 2969 // -- For a non-type template-parameter of type pointer to data 2970 // member, qualification conversions (4.4) are applied. 2971 assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); 2972 2973 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) { 2974 // Types match exactly: nothing more to do here. 2975 } else if (IsQualificationConversion(ArgType, ParamType)) { 2976 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp, 2977 Arg->isLvalue(Context) == Expr::LV_Valid); 2978 } else { 2979 // We can't perform this conversion. 2980 Diag(Arg->getSourceRange().getBegin(), 2981 diag::err_template_arg_not_convertible) 2982 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2983 Diag(Param->getLocation(), diag::note_template_param_here); 2984 return true; 2985 } 2986 2987 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2988} 2989 2990/// \brief Check a template argument against its corresponding 2991/// template template parameter. 2992/// 2993/// This routine implements the semantics of C++ [temp.arg.template]. 2994/// It returns true if an error occurred, and false otherwise. 2995bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, 2996 const TemplateArgumentLoc &Arg) { 2997 TemplateName Name = Arg.getArgument().getAsTemplate(); 2998 TemplateDecl *Template = Name.getAsTemplateDecl(); 2999 if (!Template) { 3000 // Any dependent template name is fine. 3001 assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); 3002 return false; 3003 } 3004 3005 // C++ [temp.arg.template]p1: 3006 // A template-argument for a template template-parameter shall be 3007 // the name of a class template, expressed as id-expression. Only 3008 // primary class templates are considered when matching the 3009 // template template argument with the corresponding parameter; 3010 // partial specializations are not considered even if their 3011 // parameter lists match that of the template template parameter. 3012 // 3013 // Note that we also allow template template parameters here, which 3014 // will happen when we are dealing with, e.g., class template 3015 // partial specializations. 3016 if (!isa<ClassTemplateDecl>(Template) && 3017 !isa<TemplateTemplateParmDecl>(Template)) { 3018 assert(isa<FunctionTemplateDecl>(Template) && 3019 "Only function templates are possible here"); 3020 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); 3021 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) 3022 << Template; 3023 } 3024 3025 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), 3026 Param->getTemplateParameters(), 3027 true, 3028 TPL_TemplateTemplateArgumentMatch, 3029 Arg.getLocation()); 3030} 3031 3032/// \brief Given a non-type template argument that refers to a 3033/// declaration and the type of its corresponding non-type template 3034/// parameter, produce an expression that properly refers to that 3035/// declaration. 3036Sema::OwningExprResult 3037Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg, 3038 QualType ParamType, 3039 SourceLocation Loc) { 3040 assert(Arg.getKind() == TemplateArgument::Declaration && 3041 "Only declaration template arguments permitted here"); 3042 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl()); 3043 3044 if (VD->getDeclContext()->isRecord() && 3045 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) { 3046 // If the value is a class member, we might have a pointer-to-member. 3047 // Determine whether the non-type template template parameter is of 3048 // pointer-to-member type. If so, we need to build an appropriate 3049 // expression for a pointer-to-member, since a "normal" DeclRefExpr 3050 // would refer to the member itself. 3051 if (ParamType->isMemberPointerType()) { 3052 QualType ClassType 3053 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext())); 3054 NestedNameSpecifier *Qualifier 3055 = NestedNameSpecifier::Create(Context, 0, false, ClassType.getTypePtr()); 3056 CXXScopeSpec SS; 3057 SS.setScopeRep(Qualifier); 3058 OwningExprResult RefExpr = BuildDeclRefExpr(VD, 3059 VD->getType().getNonReferenceType(), 3060 Loc, 3061 &SS); 3062 if (RefExpr.isInvalid()) 3063 return ExprError(); 3064 3065 RefExpr = CreateBuiltinUnaryOp(Loc, UnaryOperator::AddrOf, move(RefExpr)); 3066 3067 // We might need to perform a trailing qualification conversion, since 3068 // the element type on the parameter could be more qualified than the 3069 // element type in the expression we constructed. 3070 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(), 3071 ParamType.getUnqualifiedType())) { 3072 Expr *RefE = RefExpr.takeAs<Expr>(); 3073 ImpCastExprToType(RefE, ParamType.getUnqualifiedType(), 3074 CastExpr::CK_NoOp); 3075 RefExpr = Owned(RefE); 3076 } 3077 3078 assert(!RefExpr.isInvalid() && 3079 Context.hasSameType(((Expr*) RefExpr.get())->getType(), 3080 ParamType.getUnqualifiedType())); 3081 return move(RefExpr); 3082 } 3083 } 3084 3085 QualType T = VD->getType().getNonReferenceType(); 3086 if (ParamType->isPointerType()) { 3087 // When the non-type template parameter is a pointer, take the 3088 // address of the declaration. 3089 OwningExprResult RefExpr = BuildDeclRefExpr(VD, T, Loc); 3090 if (RefExpr.isInvalid()) 3091 return ExprError(); 3092 3093 if (T->isFunctionType() || T->isArrayType()) { 3094 // Decay functions and arrays. 3095 Expr *RefE = (Expr *)RefExpr.get(); 3096 DefaultFunctionArrayConversion(RefE); 3097 if (RefE != RefExpr.get()) { 3098 RefExpr.release(); 3099 RefExpr = Owned(RefE); 3100 } 3101 3102 return move(RefExpr); 3103 } 3104 3105 // Take the address of everything else 3106 return CreateBuiltinUnaryOp(Loc, UnaryOperator::AddrOf, move(RefExpr)); 3107 } 3108 3109 // If the non-type template parameter has reference type, qualify the 3110 // resulting declaration reference with the extra qualifiers on the 3111 // type that the reference refers to. 3112 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) 3113 T = Context.getQualifiedType(T, TargetRef->getPointeeType().getQualifiers()); 3114 3115 return BuildDeclRefExpr(VD, T, Loc); 3116} 3117 3118/// \brief Construct a new expression that refers to the given 3119/// integral template argument with the given source-location 3120/// information. 3121/// 3122/// This routine takes care of the mapping from an integral template 3123/// argument (which may have any integral type) to the appropriate 3124/// literal value. 3125Sema::OwningExprResult 3126Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg, 3127 SourceLocation Loc) { 3128 assert(Arg.getKind() == TemplateArgument::Integral && 3129 "Operation is only value for integral template arguments"); 3130 QualType T = Arg.getIntegralType(); 3131 if (T->isCharType() || T->isWideCharType()) 3132 return Owned(new (Context) CharacterLiteral( 3133 Arg.getAsIntegral()->getZExtValue(), 3134 T->isWideCharType(), 3135 T, 3136 Loc)); 3137 if (T->isBooleanType()) 3138 return Owned(new (Context) CXXBoolLiteralExpr( 3139 Arg.getAsIntegral()->getBoolValue(), 3140 T, 3141 Loc)); 3142 3143 return Owned(new (Context) IntegerLiteral(*Arg.getAsIntegral(), T, Loc)); 3144} 3145 3146 3147/// \brief Determine whether the given template parameter lists are 3148/// equivalent. 3149/// 3150/// \param New The new template parameter list, typically written in the 3151/// source code as part of a new template declaration. 3152/// 3153/// \param Old The old template parameter list, typically found via 3154/// name lookup of the template declared with this template parameter 3155/// list. 3156/// 3157/// \param Complain If true, this routine will produce a diagnostic if 3158/// the template parameter lists are not equivalent. 3159/// 3160/// \param Kind describes how we are to match the template parameter lists. 3161/// 3162/// \param TemplateArgLoc If this source location is valid, then we 3163/// are actually checking the template parameter list of a template 3164/// argument (New) against the template parameter list of its 3165/// corresponding template template parameter (Old). We produce 3166/// slightly different diagnostics in this scenario. 3167/// 3168/// \returns True if the template parameter lists are equal, false 3169/// otherwise. 3170bool 3171Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, 3172 TemplateParameterList *Old, 3173 bool Complain, 3174 TemplateParameterListEqualKind Kind, 3175 SourceLocation TemplateArgLoc) { 3176 if (Old->size() != New->size()) { 3177 if (Complain) { 3178 unsigned NextDiag = diag::err_template_param_list_different_arity; 3179 if (TemplateArgLoc.isValid()) { 3180 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3181 NextDiag = diag::note_template_param_list_different_arity; 3182 } 3183 Diag(New->getTemplateLoc(), NextDiag) 3184 << (New->size() > Old->size()) 3185 << (Kind != TPL_TemplateMatch) 3186 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); 3187 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) 3188 << (Kind != TPL_TemplateMatch) 3189 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); 3190 } 3191 3192 return false; 3193 } 3194 3195 for (TemplateParameterList::iterator OldParm = Old->begin(), 3196 OldParmEnd = Old->end(), NewParm = New->begin(); 3197 OldParm != OldParmEnd; ++OldParm, ++NewParm) { 3198 if ((*OldParm)->getKind() != (*NewParm)->getKind()) { 3199 if (Complain) { 3200 unsigned NextDiag = diag::err_template_param_different_kind; 3201 if (TemplateArgLoc.isValid()) { 3202 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3203 NextDiag = diag::note_template_param_different_kind; 3204 } 3205 Diag((*NewParm)->getLocation(), NextDiag) 3206 << (Kind != TPL_TemplateMatch); 3207 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration) 3208 << (Kind != TPL_TemplateMatch); 3209 } 3210 return false; 3211 } 3212 3213 if (TemplateTypeParmDecl *OldTTP 3214 = dyn_cast<TemplateTypeParmDecl>(*OldParm)) { 3215 // Template type parameters are equivalent if either both are template 3216 // type parameter packs or neither are (since we know we're at the same 3217 // index). 3218 TemplateTypeParmDecl *NewTTP = cast<TemplateTypeParmDecl>(*NewParm); 3219 if (OldTTP->isParameterPack() != NewTTP->isParameterPack()) { 3220 // FIXME: Implement the rules in C++0x [temp.arg.template]p5 that 3221 // allow one to match a template parameter pack in the template 3222 // parameter list of a template template parameter to one or more 3223 // template parameters in the template parameter list of the 3224 // corresponding template template argument. 3225 if (Complain) { 3226 unsigned NextDiag = diag::err_template_parameter_pack_non_pack; 3227 if (TemplateArgLoc.isValid()) { 3228 Diag(TemplateArgLoc, 3229 diag::err_template_arg_template_params_mismatch); 3230 NextDiag = diag::note_template_parameter_pack_non_pack; 3231 } 3232 Diag(NewTTP->getLocation(), NextDiag) 3233 << 0 << NewTTP->isParameterPack(); 3234 Diag(OldTTP->getLocation(), diag::note_template_parameter_pack_here) 3235 << 0 << OldTTP->isParameterPack(); 3236 } 3237 return false; 3238 } 3239 } else if (NonTypeTemplateParmDecl *OldNTTP 3240 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) { 3241 // The types of non-type template parameters must agree. 3242 NonTypeTemplateParmDecl *NewNTTP 3243 = cast<NonTypeTemplateParmDecl>(*NewParm); 3244 3245 // If we are matching a template template argument to a template 3246 // template parameter and one of the non-type template parameter types 3247 // is dependent, then we must wait until template instantiation time 3248 // to actually compare the arguments. 3249 if (Kind == TPL_TemplateTemplateArgumentMatch && 3250 (OldNTTP->getType()->isDependentType() || 3251 NewNTTP->getType()->isDependentType())) 3252 continue; 3253 3254 if (Context.getCanonicalType(OldNTTP->getType()) != 3255 Context.getCanonicalType(NewNTTP->getType())) { 3256 if (Complain) { 3257 unsigned NextDiag = diag::err_template_nontype_parm_different_type; 3258 if (TemplateArgLoc.isValid()) { 3259 Diag(TemplateArgLoc, 3260 diag::err_template_arg_template_params_mismatch); 3261 NextDiag = diag::note_template_nontype_parm_different_type; 3262 } 3263 Diag(NewNTTP->getLocation(), NextDiag) 3264 << NewNTTP->getType() 3265 << (Kind != TPL_TemplateMatch); 3266 Diag(OldNTTP->getLocation(), 3267 diag::note_template_nontype_parm_prev_declaration) 3268 << OldNTTP->getType(); 3269 } 3270 return false; 3271 } 3272 } else { 3273 // The template parameter lists of template template 3274 // parameters must agree. 3275 assert(isa<TemplateTemplateParmDecl>(*OldParm) && 3276 "Only template template parameters handled here"); 3277 TemplateTemplateParmDecl *OldTTP 3278 = cast<TemplateTemplateParmDecl>(*OldParm); 3279 TemplateTemplateParmDecl *NewTTP 3280 = cast<TemplateTemplateParmDecl>(*NewParm); 3281 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), 3282 OldTTP->getTemplateParameters(), 3283 Complain, 3284 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind), 3285 TemplateArgLoc)) 3286 return false; 3287 } 3288 } 3289 3290 return true; 3291} 3292 3293/// \brief Check whether a template can be declared within this scope. 3294/// 3295/// If the template declaration is valid in this scope, returns 3296/// false. Otherwise, issues a diagnostic and returns true. 3297bool 3298Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { 3299 // Find the nearest enclosing declaration scope. 3300 while ((S->getFlags() & Scope::DeclScope) == 0 || 3301 (S->getFlags() & Scope::TemplateParamScope) != 0) 3302 S = S->getParent(); 3303 3304 // C++ [temp]p2: 3305 // A template-declaration can appear only as a namespace scope or 3306 // class scope declaration. 3307 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 3308 if (Ctx && isa<LinkageSpecDecl>(Ctx) && 3309 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) 3310 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) 3311 << TemplateParams->getSourceRange(); 3312 3313 while (Ctx && isa<LinkageSpecDecl>(Ctx)) 3314 Ctx = Ctx->getParent(); 3315 3316 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) 3317 return false; 3318 3319 return Diag(TemplateParams->getTemplateLoc(), 3320 diag::err_template_outside_namespace_or_class_scope) 3321 << TemplateParams->getSourceRange(); 3322} 3323 3324/// \brief Determine what kind of template specialization the given declaration 3325/// is. 3326static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) { 3327 if (!D) 3328 return TSK_Undeclared; 3329 3330 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) 3331 return Record->getTemplateSpecializationKind(); 3332 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) 3333 return Function->getTemplateSpecializationKind(); 3334 if (VarDecl *Var = dyn_cast<VarDecl>(D)) 3335 return Var->getTemplateSpecializationKind(); 3336 3337 return TSK_Undeclared; 3338} 3339 3340/// \brief Check whether a specialization is well-formed in the current 3341/// context. 3342/// 3343/// This routine determines whether a template specialization can be declared 3344/// in the current context (C++ [temp.expl.spec]p2). 3345/// 3346/// \param S the semantic analysis object for which this check is being 3347/// performed. 3348/// 3349/// \param Specialized the entity being specialized or instantiated, which 3350/// may be a kind of template (class template, function template, etc.) or 3351/// a member of a class template (member function, static data member, 3352/// member class). 3353/// 3354/// \param PrevDecl the previous declaration of this entity, if any. 3355/// 3356/// \param Loc the location of the explicit specialization or instantiation of 3357/// this entity. 3358/// 3359/// \param IsPartialSpecialization whether this is a partial specialization of 3360/// a class template. 3361/// 3362/// \returns true if there was an error that we cannot recover from, false 3363/// otherwise. 3364static bool CheckTemplateSpecializationScope(Sema &S, 3365 NamedDecl *Specialized, 3366 NamedDecl *PrevDecl, 3367 SourceLocation Loc, 3368 bool IsPartialSpecialization) { 3369 // Keep these "kind" numbers in sync with the %select statements in the 3370 // various diagnostics emitted by this routine. 3371 int EntityKind = 0; 3372 bool isTemplateSpecialization = false; 3373 if (isa<ClassTemplateDecl>(Specialized)) { 3374 EntityKind = IsPartialSpecialization? 1 : 0; 3375 isTemplateSpecialization = true; 3376 } else if (isa<FunctionTemplateDecl>(Specialized)) { 3377 EntityKind = 2; 3378 isTemplateSpecialization = true; 3379 } else if (isa<CXXMethodDecl>(Specialized)) 3380 EntityKind = 3; 3381 else if (isa<VarDecl>(Specialized)) 3382 EntityKind = 4; 3383 else if (isa<RecordDecl>(Specialized)) 3384 EntityKind = 5; 3385 else { 3386 S.Diag(Loc, diag::err_template_spec_unknown_kind); 3387 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3388 return true; 3389 } 3390 3391 // C++ [temp.expl.spec]p2: 3392 // An explicit specialization shall be declared in the namespace 3393 // of which the template is a member, or, for member templates, in 3394 // the namespace of which the enclosing class or enclosing class 3395 // template is a member. An explicit specialization of a member 3396 // function, member class or static data member of a class 3397 // template shall be declared in the namespace of which the class 3398 // template is a member. Such a declaration may also be a 3399 // definition. If the declaration is not a definition, the 3400 // specialization may be defined later in the name- space in which 3401 // the explicit specialization was declared, or in a namespace 3402 // that encloses the one in which the explicit specialization was 3403 // declared. 3404 if (S.CurContext->getLookupContext()->isFunctionOrMethod()) { 3405 S.Diag(Loc, diag::err_template_spec_decl_function_scope) 3406 << Specialized; 3407 return true; 3408 } 3409 3410 if (S.CurContext->isRecord() && !IsPartialSpecialization) { 3411 S.Diag(Loc, diag::err_template_spec_decl_class_scope) 3412 << Specialized; 3413 return true; 3414 } 3415 3416 // C++ [temp.class.spec]p6: 3417 // A class template partial specialization may be declared or redeclared 3418 // in any namespace scope in which its definition may be defined (14.5.1 3419 // and 14.5.2). 3420 bool ComplainedAboutScope = false; 3421 DeclContext *SpecializedContext 3422 = Specialized->getDeclContext()->getEnclosingNamespaceContext(); 3423 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); 3424 if ((!PrevDecl || 3425 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || 3426 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ 3427 // There is no prior declaration of this entity, so this 3428 // specialization must be in the same context as the template 3429 // itself. 3430 if (!DC->Equals(SpecializedContext)) { 3431 if (isa<TranslationUnitDecl>(SpecializedContext)) 3432 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) 3433 << EntityKind << Specialized; 3434 else if (isa<NamespaceDecl>(SpecializedContext)) 3435 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope) 3436 << EntityKind << Specialized 3437 << cast<NamedDecl>(SpecializedContext); 3438 3439 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3440 ComplainedAboutScope = true; 3441 } 3442 } 3443 3444 // Make sure that this redeclaration (or definition) occurs in an enclosing 3445 // namespace. 3446 // Note that HandleDeclarator() performs this check for explicit 3447 // specializations of function templates, static data members, and member 3448 // functions, so we skip the check here for those kinds of entities. 3449 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. 3450 // Should we refactor that check, so that it occurs later? 3451 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && 3452 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || 3453 isa<FunctionDecl>(Specialized))) { 3454 if (isa<TranslationUnitDecl>(SpecializedContext)) 3455 S.Diag(Loc, diag::err_template_spec_redecl_global_scope) 3456 << EntityKind << Specialized; 3457 else if (isa<NamespaceDecl>(SpecializedContext)) 3458 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) 3459 << EntityKind << Specialized 3460 << cast<NamedDecl>(SpecializedContext); 3461 3462 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3463 } 3464 3465 // FIXME: check for specialization-after-instantiation errors and such. 3466 3467 return false; 3468} 3469 3470/// \brief Check the non-type template arguments of a class template 3471/// partial specialization according to C++ [temp.class.spec]p9. 3472/// 3473/// \param TemplateParams the template parameters of the primary class 3474/// template. 3475/// 3476/// \param TemplateArg the template arguments of the class template 3477/// partial specialization. 3478/// 3479/// \param MirrorsPrimaryTemplate will be set true if the class 3480/// template partial specialization arguments are identical to the 3481/// implicit template arguments of the primary template. This is not 3482/// necessarily an error (C++0x), and it is left to the caller to diagnose 3483/// this condition when it is an error. 3484/// 3485/// \returns true if there was an error, false otherwise. 3486bool Sema::CheckClassTemplatePartialSpecializationArgs( 3487 TemplateParameterList *TemplateParams, 3488 const TemplateArgumentListBuilder &TemplateArgs, 3489 bool &MirrorsPrimaryTemplate) { 3490 // FIXME: the interface to this function will have to change to 3491 // accommodate variadic templates. 3492 MirrorsPrimaryTemplate = true; 3493 3494 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments(); 3495 3496 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3497 // Determine whether the template argument list of the partial 3498 // specialization is identical to the implicit argument list of 3499 // the primary template. The caller may need to diagnostic this as 3500 // an error per C++ [temp.class.spec]p9b3. 3501 if (MirrorsPrimaryTemplate) { 3502 if (TemplateTypeParmDecl *TTP 3503 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) { 3504 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) != 3505 Context.getCanonicalType(ArgList[I].getAsType())) 3506 MirrorsPrimaryTemplate = false; 3507 } else if (TemplateTemplateParmDecl *TTP 3508 = dyn_cast<TemplateTemplateParmDecl>( 3509 TemplateParams->getParam(I))) { 3510 TemplateName Name = ArgList[I].getAsTemplate(); 3511 TemplateTemplateParmDecl *ArgDecl 3512 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()); 3513 if (!ArgDecl || 3514 ArgDecl->getIndex() != TTP->getIndex() || 3515 ArgDecl->getDepth() != TTP->getDepth()) 3516 MirrorsPrimaryTemplate = false; 3517 } 3518 } 3519 3520 NonTypeTemplateParmDecl *Param 3521 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); 3522 if (!Param) { 3523 continue; 3524 } 3525 3526 Expr *ArgExpr = ArgList[I].getAsExpr(); 3527 if (!ArgExpr) { 3528 MirrorsPrimaryTemplate = false; 3529 continue; 3530 } 3531 3532 // C++ [temp.class.spec]p8: 3533 // A non-type argument is non-specialized if it is the name of a 3534 // non-type parameter. All other non-type arguments are 3535 // specialized. 3536 // 3537 // Below, we check the two conditions that only apply to 3538 // specialized non-type arguments, so skip any non-specialized 3539 // arguments. 3540 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) 3541 if (NonTypeTemplateParmDecl *NTTP 3542 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) { 3543 if (MirrorsPrimaryTemplate && 3544 (Param->getIndex() != NTTP->getIndex() || 3545 Param->getDepth() != NTTP->getDepth())) 3546 MirrorsPrimaryTemplate = false; 3547 3548 continue; 3549 } 3550 3551 // C++ [temp.class.spec]p9: 3552 // Within the argument list of a class template partial 3553 // specialization, the following restrictions apply: 3554 // -- A partially specialized non-type argument expression 3555 // shall not involve a template parameter of the partial 3556 // specialization except when the argument expression is a 3557 // simple identifier. 3558 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { 3559 Diag(ArgExpr->getLocStart(), 3560 diag::err_dependent_non_type_arg_in_partial_spec) 3561 << ArgExpr->getSourceRange(); 3562 return true; 3563 } 3564 3565 // -- The type of a template parameter corresponding to a 3566 // specialized non-type argument shall not be dependent on a 3567 // parameter of the specialization. 3568 if (Param->getType()->isDependentType()) { 3569 Diag(ArgExpr->getLocStart(), 3570 diag::err_dependent_typed_non_type_arg_in_partial_spec) 3571 << Param->getType() 3572 << ArgExpr->getSourceRange(); 3573 Diag(Param->getLocation(), diag::note_template_param_here); 3574 return true; 3575 } 3576 3577 MirrorsPrimaryTemplate = false; 3578 } 3579 3580 return false; 3581} 3582 3583/// \brief Retrieve the previous declaration of the given declaration. 3584static NamedDecl *getPreviousDecl(NamedDecl *ND) { 3585 if (VarDecl *VD = dyn_cast<VarDecl>(ND)) 3586 return VD->getPreviousDeclaration(); 3587 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) 3588 return FD->getPreviousDeclaration(); 3589 if (TagDecl *TD = dyn_cast<TagDecl>(ND)) 3590 return TD->getPreviousDeclaration(); 3591 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND)) 3592 return TD->getPreviousDeclaration(); 3593 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND)) 3594 return FTD->getPreviousDeclaration(); 3595 if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND)) 3596 return CTD->getPreviousDeclaration(); 3597 return 0; 3598} 3599 3600Sema::DeclResult 3601Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, 3602 TagUseKind TUK, 3603 SourceLocation KWLoc, 3604 CXXScopeSpec &SS, 3605 TemplateTy TemplateD, 3606 SourceLocation TemplateNameLoc, 3607 SourceLocation LAngleLoc, 3608 ASTTemplateArgsPtr TemplateArgsIn, 3609 SourceLocation RAngleLoc, 3610 AttributeList *Attr, 3611 MultiTemplateParamsArg TemplateParameterLists) { 3612 assert(TUK != TUK_Reference && "References are not specializations"); 3613 3614 // Find the class template we're specializing 3615 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 3616 ClassTemplateDecl *ClassTemplate 3617 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); 3618 3619 if (!ClassTemplate) { 3620 Diag(TemplateNameLoc, diag::err_not_class_template_specialization) 3621 << (Name.getAsTemplateDecl() && 3622 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); 3623 return true; 3624 } 3625 3626 bool isExplicitSpecialization = false; 3627 bool isPartialSpecialization = false; 3628 3629 // Check the validity of the template headers that introduce this 3630 // template. 3631 // FIXME: We probably shouldn't complain about these headers for 3632 // friend declarations. 3633 bool Invalid = false; 3634 TemplateParameterList *TemplateParams 3635 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS, 3636 (TemplateParameterList**)TemplateParameterLists.get(), 3637 TemplateParameterLists.size(), 3638 TUK == TUK_Friend, 3639 isExplicitSpecialization, 3640 Invalid); 3641 if (Invalid) 3642 return true; 3643 3644 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 3645 if (TemplateParams) 3646 --NumMatchedTemplateParamLists; 3647 3648 if (TemplateParams && TemplateParams->size() > 0) { 3649 isPartialSpecialization = true; 3650 3651 // C++ [temp.class.spec]p10: 3652 // The template parameter list of a specialization shall not 3653 // contain default template argument values. 3654 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3655 Decl *Param = TemplateParams->getParam(I); 3656 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { 3657 if (TTP->hasDefaultArgument()) { 3658 Diag(TTP->getDefaultArgumentLoc(), 3659 diag::err_default_arg_in_partial_spec); 3660 TTP->removeDefaultArgument(); 3661 } 3662 } else if (NonTypeTemplateParmDecl *NTTP 3663 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 3664 if (Expr *DefArg = NTTP->getDefaultArgument()) { 3665 Diag(NTTP->getDefaultArgumentLoc(), 3666 diag::err_default_arg_in_partial_spec) 3667 << DefArg->getSourceRange(); 3668 NTTP->removeDefaultArgument(); 3669 DefArg->Destroy(Context); 3670 } 3671 } else { 3672 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); 3673 if (TTP->hasDefaultArgument()) { 3674 Diag(TTP->getDefaultArgument().getLocation(), 3675 diag::err_default_arg_in_partial_spec) 3676 << TTP->getDefaultArgument().getSourceRange(); 3677 TTP->removeDefaultArgument(); 3678 } 3679 } 3680 } 3681 } else if (TemplateParams) { 3682 if (TUK == TUK_Friend) 3683 Diag(KWLoc, diag::err_template_spec_friend) 3684 << FixItHint::CreateRemoval( 3685 SourceRange(TemplateParams->getTemplateLoc(), 3686 TemplateParams->getRAngleLoc())) 3687 << SourceRange(LAngleLoc, RAngleLoc); 3688 else 3689 isExplicitSpecialization = true; 3690 } else if (TUK != TUK_Friend) { 3691 Diag(KWLoc, diag::err_template_spec_needs_header) 3692 << FixItHint::CreateInsertion(KWLoc, "template<> "); 3693 isExplicitSpecialization = true; 3694 } 3695 3696 // Check that the specialization uses the same tag kind as the 3697 // original template. 3698 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 3699 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!"); 3700 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 3701 Kind, KWLoc, 3702 *ClassTemplate->getIdentifier())) { 3703 Diag(KWLoc, diag::err_use_with_wrong_tag) 3704 << ClassTemplate 3705 << FixItHint::CreateReplacement(KWLoc, 3706 ClassTemplate->getTemplatedDecl()->getKindName()); 3707 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 3708 diag::note_previous_use); 3709 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 3710 } 3711 3712 // Translate the parser's template argument list in our AST format. 3713 TemplateArgumentListInfo TemplateArgs; 3714 TemplateArgs.setLAngleLoc(LAngleLoc); 3715 TemplateArgs.setRAngleLoc(RAngleLoc); 3716 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 3717 3718 // Check that the template argument list is well-formed for this 3719 // template. 3720 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 3721 TemplateArgs.size()); 3722 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 3723 TemplateArgs, false, Converted)) 3724 return true; 3725 3726 assert((Converted.structuredSize() == 3727 ClassTemplate->getTemplateParameters()->size()) && 3728 "Converted template argument list is too short!"); 3729 3730 // Find the class template (partial) specialization declaration that 3731 // corresponds to these arguments. 3732 llvm::FoldingSetNodeID ID; 3733 if (isPartialSpecialization) { 3734 bool MirrorsPrimaryTemplate; 3735 if (CheckClassTemplatePartialSpecializationArgs( 3736 ClassTemplate->getTemplateParameters(), 3737 Converted, MirrorsPrimaryTemplate)) 3738 return true; 3739 3740 if (MirrorsPrimaryTemplate) { 3741 // C++ [temp.class.spec]p9b3: 3742 // 3743 // -- The argument list of the specialization shall not be identical 3744 // to the implicit argument list of the primary template. 3745 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) 3746 << (TUK == TUK_Definition) 3747 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc)); 3748 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, 3749 ClassTemplate->getIdentifier(), 3750 TemplateNameLoc, 3751 Attr, 3752 TemplateParams, 3753 AS_none); 3754 } 3755 3756 // FIXME: Diagnose friend partial specializations 3757 3758 if (!Name.isDependent() && 3759 !TemplateSpecializationType::anyDependentTemplateArguments( 3760 TemplateArgs.getArgumentArray(), 3761 TemplateArgs.size())) { 3762 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized) 3763 << ClassTemplate->getDeclName(); 3764 isPartialSpecialization = false; 3765 } else { 3766 // FIXME: Template parameter list matters, too 3767 ClassTemplatePartialSpecializationDecl::Profile(ID, 3768 Converted.getFlatArguments(), 3769 Converted.flatSize(), 3770 Context); 3771 } 3772 } 3773 3774 if (!isPartialSpecialization) 3775 ClassTemplateSpecializationDecl::Profile(ID, 3776 Converted.getFlatArguments(), 3777 Converted.flatSize(), 3778 Context); 3779 void *InsertPos = 0; 3780 ClassTemplateSpecializationDecl *PrevDecl = 0; 3781 3782 if (isPartialSpecialization) 3783 PrevDecl 3784 = ClassTemplate->getPartialSpecializations().FindNodeOrInsertPos(ID, 3785 InsertPos); 3786 else 3787 PrevDecl 3788 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 3789 3790 ClassTemplateSpecializationDecl *Specialization = 0; 3791 3792 // Check whether we can declare a class template specialization in 3793 // the current scope. 3794 if (TUK != TUK_Friend && 3795 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, 3796 TemplateNameLoc, 3797 isPartialSpecialization)) 3798 return true; 3799 3800 // The canonical type 3801 QualType CanonType; 3802 if (PrevDecl && 3803 (PrevDecl->getSpecializationKind() == TSK_Undeclared || 3804 TUK == TUK_Friend)) { 3805 // Since the only prior class template specialization with these 3806 // arguments was referenced but not declared, or we're only 3807 // referencing this specialization as a friend, reuse that 3808 // declaration node as our own, updating its source location to 3809 // reflect our new declaration. 3810 Specialization = PrevDecl; 3811 Specialization->setLocation(TemplateNameLoc); 3812 PrevDecl = 0; 3813 CanonType = Context.getTypeDeclType(Specialization); 3814 } else if (isPartialSpecialization) { 3815 // Build the canonical type that describes the converted template 3816 // arguments of the class template partial specialization. 3817 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); 3818 CanonType = Context.getTemplateSpecializationType(CanonTemplate, 3819 Converted.getFlatArguments(), 3820 Converted.flatSize()); 3821 3822 // Create a new class template partial specialization declaration node. 3823 ClassTemplatePartialSpecializationDecl *PrevPartial 3824 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); 3825 unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber() 3826 : ClassTemplate->getPartialSpecializations().size(); 3827 ClassTemplatePartialSpecializationDecl *Partial 3828 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind, 3829 ClassTemplate->getDeclContext(), 3830 TemplateNameLoc, 3831 TemplateParams, 3832 ClassTemplate, 3833 Converted, 3834 TemplateArgs, 3835 CanonType, 3836 PrevPartial, 3837 SequenceNumber); 3838 SetNestedNameSpecifier(Partial, SS); 3839 if (NumMatchedTemplateParamLists > 0) { 3840 Partial->setTemplateParameterListsInfo(Context, 3841 NumMatchedTemplateParamLists, 3842 (TemplateParameterList**) TemplateParameterLists.release()); 3843 } 3844 3845 if (PrevPartial) { 3846 ClassTemplate->getPartialSpecializations().RemoveNode(PrevPartial); 3847 ClassTemplate->getPartialSpecializations().GetOrInsertNode(Partial); 3848 } else { 3849 ClassTemplate->getPartialSpecializations().InsertNode(Partial, InsertPos); 3850 } 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 << std::string("<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) { 3902 Specialization->setTemplateParameterListsInfo(Context, 3903 NumMatchedTemplateParamLists, 3904 (TemplateParameterList**) TemplateParameterLists.release()); 3905 } 3906 3907 if (PrevDecl) { 3908 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 3909 ClassTemplate->getSpecializations().GetOrInsertNode(Specialization); 3910 } else { 3911 ClassTemplate->getSpecializations().InsertNode(Specialization, 3912 InsertPos); 3913 } 3914 3915 CanonType = Context.getTypeDeclType(Specialization); 3916 } 3917 3918 // C++ [temp.expl.spec]p6: 3919 // If a template, a member template or the member of a class template is 3920 // explicitly specialized then that specialization shall be declared 3921 // before the first use of that specialization that would cause an implicit 3922 // instantiation to take place, in every translation unit in which such a 3923 // use occurs; no diagnostic is required. 3924 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { 3925 bool Okay = false; 3926 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 3927 // Is there any previous explicit specialization declaration? 3928 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) { 3929 Okay = true; 3930 break; 3931 } 3932 } 3933 3934 if (!Okay) { 3935 SourceRange Range(TemplateNameLoc, RAngleLoc); 3936 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) 3937 << Context.getTypeDeclType(Specialization) << Range; 3938 3939 Diag(PrevDecl->getPointOfInstantiation(), 3940 diag::note_instantiation_required_here) 3941 << (PrevDecl->getTemplateSpecializationKind() 3942 != TSK_ImplicitInstantiation); 3943 return true; 3944 } 3945 } 3946 3947 // If this is not a friend, note that this is an explicit specialization. 3948 if (TUK != TUK_Friend) 3949 Specialization->setSpecializationKind(TSK_ExplicitSpecialization); 3950 3951 // Check that this isn't a redefinition of this specialization. 3952 if (TUK == TUK_Definition) { 3953 if (RecordDecl *Def = Specialization->getDefinition()) { 3954 SourceRange Range(TemplateNameLoc, RAngleLoc); 3955 Diag(TemplateNameLoc, diag::err_redefinition) 3956 << Context.getTypeDeclType(Specialization) << Range; 3957 Diag(Def->getLocation(), diag::note_previous_definition); 3958 Specialization->setInvalidDecl(); 3959 return true; 3960 } 3961 } 3962 3963 // Build the fully-sugared type for this class template 3964 // specialization as the user wrote in the specialization 3965 // itself. This means that we'll pretty-print the type retrieved 3966 // from the specialization's declaration the way that the user 3967 // actually wrote the specialization, rather than formatting the 3968 // name based on the "canonical" representation used to store the 3969 // template arguments in the specialization. 3970 TypeSourceInfo *WrittenTy 3971 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 3972 TemplateArgs, CanonType); 3973 if (TUK != TUK_Friend) { 3974 Specialization->setTypeAsWritten(WrittenTy); 3975 if (TemplateParams) 3976 Specialization->setTemplateKeywordLoc(TemplateParams->getTemplateLoc()); 3977 } 3978 TemplateArgsIn.release(); 3979 3980 // C++ [temp.expl.spec]p9: 3981 // A template explicit specialization is in the scope of the 3982 // namespace in which the template was defined. 3983 // 3984 // We actually implement this paragraph where we set the semantic 3985 // context (in the creation of the ClassTemplateSpecializationDecl), 3986 // but we also maintain the lexical context where the actual 3987 // definition occurs. 3988 Specialization->setLexicalDeclContext(CurContext); 3989 3990 // We may be starting the definition of this specialization. 3991 if (TUK == TUK_Definition) 3992 Specialization->startDefinition(); 3993 3994 if (TUK == TUK_Friend) { 3995 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 3996 TemplateNameLoc, 3997 WrittenTy, 3998 /*FIXME:*/KWLoc); 3999 Friend->setAccess(AS_public); 4000 CurContext->addDecl(Friend); 4001 } else { 4002 // Add the specialization into its lexical context, so that it can 4003 // be seen when iterating through the list of declarations in that 4004 // context. However, specializations are not found by name lookup. 4005 CurContext->addDecl(Specialization); 4006 } 4007 return DeclPtrTy::make(Specialization); 4008} 4009 4010Sema::DeclPtrTy 4011Sema::ActOnTemplateDeclarator(Scope *S, 4012 MultiTemplateParamsArg TemplateParameterLists, 4013 Declarator &D) { 4014 return HandleDeclarator(S, D, move(TemplateParameterLists), false); 4015} 4016 4017Sema::DeclPtrTy 4018Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, 4019 MultiTemplateParamsArg TemplateParameterLists, 4020 Declarator &D) { 4021 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4022 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4023 "Not a function declarator!"); 4024 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4025 4026 if (FTI.hasPrototype) { 4027 // FIXME: Diagnose arguments without names in C. 4028 } 4029 4030 Scope *ParentScope = FnBodyScope->getParent(); 4031 4032 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4033 move(TemplateParameterLists), 4034 /*IsFunctionDefinition=*/true); 4035 if (FunctionTemplateDecl *FunctionTemplate 4036 = dyn_cast_or_null<FunctionTemplateDecl>(DP.getAs<Decl>())) 4037 return ActOnStartOfFunctionDef(FnBodyScope, 4038 DeclPtrTy::make(FunctionTemplate->getTemplatedDecl())); 4039 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP.getAs<Decl>())) 4040 return ActOnStartOfFunctionDef(FnBodyScope, DeclPtrTy::make(Function)); 4041 return DeclPtrTy(); 4042} 4043 4044/// \brief Strips various properties off an implicit instantiation 4045/// that has just been explicitly specialized. 4046static void StripImplicitInstantiation(NamedDecl *D) { 4047 D->invalidateAttrs(); 4048 4049 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 4050 FD->setInlineSpecified(false); 4051 } 4052} 4053 4054/// \brief Diagnose cases where we have an explicit template specialization 4055/// before/after an explicit template instantiation, producing diagnostics 4056/// for those cases where they are required and determining whether the 4057/// new specialization/instantiation will have any effect. 4058/// 4059/// \param NewLoc the location of the new explicit specialization or 4060/// instantiation. 4061/// 4062/// \param NewTSK the kind of the new explicit specialization or instantiation. 4063/// 4064/// \param PrevDecl the previous declaration of the entity. 4065/// 4066/// \param PrevTSK the kind of the old explicit specialization or instantiatin. 4067/// 4068/// \param PrevPointOfInstantiation if valid, indicates where the previus 4069/// declaration was instantiated (either implicitly or explicitly). 4070/// 4071/// \param HasNoEffect will be set to true to indicate that the new 4072/// specialization or instantiation has no effect and should be ignored. 4073/// 4074/// \returns true if there was an error that should prevent the introduction of 4075/// the new declaration into the AST, false otherwise. 4076bool 4077Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, 4078 TemplateSpecializationKind NewTSK, 4079 NamedDecl *PrevDecl, 4080 TemplateSpecializationKind PrevTSK, 4081 SourceLocation PrevPointOfInstantiation, 4082 bool &HasNoEffect) { 4083 HasNoEffect = false; 4084 4085 switch (NewTSK) { 4086 case TSK_Undeclared: 4087 case TSK_ImplicitInstantiation: 4088 assert(false && "Don't check implicit instantiations here"); 4089 return false; 4090 4091 case TSK_ExplicitSpecialization: 4092 switch (PrevTSK) { 4093 case TSK_Undeclared: 4094 case TSK_ExplicitSpecialization: 4095 // Okay, we're just specializing something that is either already 4096 // explicitly specialized or has merely been mentioned without any 4097 // instantiation. 4098 return false; 4099 4100 case TSK_ImplicitInstantiation: 4101 if (PrevPointOfInstantiation.isInvalid()) { 4102 // The declaration itself has not actually been instantiated, so it is 4103 // still okay to specialize it. 4104 StripImplicitInstantiation(PrevDecl); 4105 return false; 4106 } 4107 // Fall through 4108 4109 case TSK_ExplicitInstantiationDeclaration: 4110 case TSK_ExplicitInstantiationDefinition: 4111 assert((PrevTSK == TSK_ImplicitInstantiation || 4112 PrevPointOfInstantiation.isValid()) && 4113 "Explicit instantiation without point of instantiation?"); 4114 4115 // C++ [temp.expl.spec]p6: 4116 // If a template, a member template or the member of a class template 4117 // is explicitly specialized then that specialization shall be declared 4118 // before the first use of that specialization that would cause an 4119 // implicit instantiation to take place, in every translation unit in 4120 // which such a use occurs; no diagnostic is required. 4121 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 4122 // Is there any previous explicit specialization declaration? 4123 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) 4124 return false; 4125 } 4126 4127 Diag(NewLoc, diag::err_specialization_after_instantiation) 4128 << PrevDecl; 4129 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) 4130 << (PrevTSK != TSK_ImplicitInstantiation); 4131 4132 return true; 4133 } 4134 break; 4135 4136 case TSK_ExplicitInstantiationDeclaration: 4137 switch (PrevTSK) { 4138 case TSK_ExplicitInstantiationDeclaration: 4139 // This explicit instantiation declaration is redundant (that's okay). 4140 HasNoEffect = true; 4141 return false; 4142 4143 case TSK_Undeclared: 4144 case TSK_ImplicitInstantiation: 4145 // We're explicitly instantiating something that may have already been 4146 // implicitly instantiated; that's fine. 4147 return false; 4148 4149 case TSK_ExplicitSpecialization: 4150 // C++0x [temp.explicit]p4: 4151 // For a given set of template parameters, if an explicit instantiation 4152 // of a template appears after a declaration of an explicit 4153 // specialization for that template, the explicit instantiation has no 4154 // effect. 4155 HasNoEffect = true; 4156 return false; 4157 4158 case TSK_ExplicitInstantiationDefinition: 4159 // C++0x [temp.explicit]p10: 4160 // If an entity is the subject of both an explicit instantiation 4161 // declaration and an explicit instantiation definition in the same 4162 // translation unit, the definition shall follow the declaration. 4163 Diag(NewLoc, 4164 diag::err_explicit_instantiation_declaration_after_definition); 4165 Diag(PrevPointOfInstantiation, 4166 diag::note_explicit_instantiation_definition_here); 4167 assert(PrevPointOfInstantiation.isValid() && 4168 "Explicit instantiation without point of instantiation?"); 4169 HasNoEffect = true; 4170 return false; 4171 } 4172 break; 4173 4174 case TSK_ExplicitInstantiationDefinition: 4175 switch (PrevTSK) { 4176 case TSK_Undeclared: 4177 case TSK_ImplicitInstantiation: 4178 // We're explicitly instantiating something that may have already been 4179 // implicitly instantiated; that's fine. 4180 return false; 4181 4182 case TSK_ExplicitSpecialization: 4183 // C++ DR 259, C++0x [temp.explicit]p4: 4184 // For a given set of template parameters, if an explicit 4185 // instantiation of a template appears after a declaration of 4186 // an explicit specialization for that template, the explicit 4187 // instantiation has no effect. 4188 // 4189 // In C++98/03 mode, we only give an extension warning here, because it 4190 // is not harmful to try to explicitly instantiate something that 4191 // has been explicitly specialized. 4192 if (!getLangOptions().CPlusPlus0x) { 4193 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization) 4194 << PrevDecl; 4195 Diag(PrevDecl->getLocation(), 4196 diag::note_previous_template_specialization); 4197 } 4198 HasNoEffect = true; 4199 return false; 4200 4201 case TSK_ExplicitInstantiationDeclaration: 4202 // We're explicity instantiating a definition for something for which we 4203 // were previously asked to suppress instantiations. That's fine. 4204 return false; 4205 4206 case TSK_ExplicitInstantiationDefinition: 4207 // C++0x [temp.spec]p5: 4208 // For a given template and a given set of template-arguments, 4209 // - an explicit instantiation definition shall appear at most once 4210 // in a program, 4211 Diag(NewLoc, diag::err_explicit_instantiation_duplicate) 4212 << PrevDecl; 4213 Diag(PrevPointOfInstantiation, 4214 diag::note_previous_explicit_instantiation); 4215 HasNoEffect = true; 4216 return false; 4217 } 4218 break; 4219 } 4220 4221 assert(false && "Missing specialization/instantiation case?"); 4222 4223 return false; 4224} 4225 4226/// \brief Perform semantic analysis for the given dependent function 4227/// template specialization. The only possible way to get a dependent 4228/// function template specialization is with a friend declaration, 4229/// like so: 4230/// 4231/// template <class T> void foo(T); 4232/// template <class T> class A { 4233/// friend void foo<>(T); 4234/// }; 4235/// 4236/// There really isn't any useful analysis we can do here, so we 4237/// just store the information. 4238bool 4239Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD, 4240 const TemplateArgumentListInfo &ExplicitTemplateArgs, 4241 LookupResult &Previous) { 4242 // Remove anything from Previous that isn't a function template in 4243 // the correct context. 4244 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 4245 LookupResult::Filter F = Previous.makeFilter(); 4246 while (F.hasNext()) { 4247 NamedDecl *D = F.next()->getUnderlyingDecl(); 4248 if (!isa<FunctionTemplateDecl>(D) || 4249 !FDLookupContext->Equals(D->getDeclContext()->getLookupContext())) 4250 F.erase(); 4251 } 4252 F.done(); 4253 4254 // Should this be diagnosed here? 4255 if (Previous.empty()) return true; 4256 4257 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(), 4258 ExplicitTemplateArgs); 4259 return false; 4260} 4261 4262/// \brief Perform semantic analysis for the given function template 4263/// specialization. 4264/// 4265/// This routine performs all of the semantic analysis required for an 4266/// explicit function template specialization. On successful completion, 4267/// the function declaration \p FD will become a function template 4268/// specialization. 4269/// 4270/// \param FD the function declaration, which will be updated to become a 4271/// function template specialization. 4272/// 4273/// \param ExplicitTemplateArgs the explicitly-provided template arguments, 4274/// if any. Note that this may be valid info even when 0 arguments are 4275/// explicitly provided as in, e.g., \c void sort<>(char*, char*); 4276/// as it anyway contains info on the angle brackets locations. 4277/// 4278/// \param PrevDecl the set of declarations that may be specialized by 4279/// this function specialization. 4280bool 4281Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, 4282 const TemplateArgumentListInfo *ExplicitTemplateArgs, 4283 LookupResult &Previous) { 4284 // The set of function template specializations that could match this 4285 // explicit function template specialization. 4286 UnresolvedSet<8> Candidates; 4287 4288 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 4289 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4290 I != E; ++I) { 4291 NamedDecl *Ovl = (*I)->getUnderlyingDecl(); 4292 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { 4293 // Only consider templates found within the same semantic lookup scope as 4294 // FD. 4295 if (!FDLookupContext->Equals(Ovl->getDeclContext()->getLookupContext())) 4296 continue; 4297 4298 // C++ [temp.expl.spec]p11: 4299 // A trailing template-argument can be left unspecified in the 4300 // template-id naming an explicit function template specialization 4301 // provided it can be deduced from the function argument type. 4302 // Perform template argument deduction to determine whether we may be 4303 // specializing this template. 4304 // FIXME: It is somewhat wasteful to build 4305 TemplateDeductionInfo Info(Context, FD->getLocation()); 4306 FunctionDecl *Specialization = 0; 4307 if (TemplateDeductionResult TDK 4308 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, 4309 FD->getType(), 4310 Specialization, 4311 Info)) { 4312 // FIXME: Template argument deduction failed; record why it failed, so 4313 // that we can provide nifty diagnostics. 4314 (void)TDK; 4315 continue; 4316 } 4317 4318 // Record this candidate. 4319 Candidates.addDecl(Specialization, I.getAccess()); 4320 } 4321 } 4322 4323 // Find the most specialized function template. 4324 UnresolvedSetIterator Result 4325 = getMostSpecialized(Candidates.begin(), Candidates.end(), 4326 TPOC_Other, FD->getLocation(), 4327 PDiag(diag::err_function_template_spec_no_match) 4328 << FD->getDeclName(), 4329 PDiag(diag::err_function_template_spec_ambiguous) 4330 << FD->getDeclName() << (ExplicitTemplateArgs != 0), 4331 PDiag(diag::note_function_template_spec_matched)); 4332 if (Result == Candidates.end()) 4333 return true; 4334 4335 // Ignore access information; it doesn't figure into redeclaration checking. 4336 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 4337 Specialization->setLocation(FD->getLocation()); 4338 4339 // FIXME: Check if the prior specialization has a point of instantiation. 4340 // If so, we have run afoul of . 4341 4342 // If this is a friend declaration, then we're not really declaring 4343 // an explicit specialization. 4344 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None); 4345 4346 // Check the scope of this explicit specialization. 4347 if (!isFriend && 4348 CheckTemplateSpecializationScope(*this, 4349 Specialization->getPrimaryTemplate(), 4350 Specialization, FD->getLocation(), 4351 false)) 4352 return true; 4353 4354 // C++ [temp.expl.spec]p6: 4355 // If a template, a member template or the member of a class template is 4356 // explicitly specialized then that specialization shall be declared 4357 // before the first use of that specialization that would cause an implicit 4358 // instantiation to take place, in every translation unit in which such a 4359 // use occurs; no diagnostic is required. 4360 FunctionTemplateSpecializationInfo *SpecInfo 4361 = Specialization->getTemplateSpecializationInfo(); 4362 assert(SpecInfo && "Function template specialization info missing?"); 4363 4364 bool HasNoEffect = false; 4365 if (!isFriend && 4366 CheckSpecializationInstantiationRedecl(FD->getLocation(), 4367 TSK_ExplicitSpecialization, 4368 Specialization, 4369 SpecInfo->getTemplateSpecializationKind(), 4370 SpecInfo->getPointOfInstantiation(), 4371 HasNoEffect)) 4372 return true; 4373 4374 // Mark the prior declaration as an explicit specialization, so that later 4375 // clients know that this is an explicit specialization. 4376 if (!isFriend) 4377 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); 4378 4379 // Turn the given function declaration into a function template 4380 // specialization, with the template arguments from the previous 4381 // specialization. 4382 // Take copies of (semantic and syntactic) template argument lists. 4383 const TemplateArgumentList* TemplArgs = new (Context) 4384 TemplateArgumentList(Specialization->getTemplateSpecializationArgs()); 4385 const TemplateArgumentListInfo* TemplArgsAsWritten = ExplicitTemplateArgs 4386 ? new (Context) TemplateArgumentListInfo(*ExplicitTemplateArgs) : 0; 4387 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(), 4388 TemplArgs, /*InsertPos=*/0, 4389 SpecInfo->getTemplateSpecializationKind(), 4390 TemplArgsAsWritten); 4391 4392 // The "previous declaration" for this function template specialization is 4393 // the prior function template specialization. 4394 Previous.clear(); 4395 Previous.addDecl(Specialization); 4396 return false; 4397} 4398 4399/// \brief Perform semantic analysis for the given non-template member 4400/// specialization. 4401/// 4402/// This routine performs all of the semantic analysis required for an 4403/// explicit member function specialization. On successful completion, 4404/// the function declaration \p FD will become a member function 4405/// specialization. 4406/// 4407/// \param Member the member declaration, which will be updated to become a 4408/// specialization. 4409/// 4410/// \param Previous the set of declarations, one of which may be specialized 4411/// by this function specialization; the set will be modified to contain the 4412/// redeclared member. 4413bool 4414Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { 4415 assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); 4416 4417 // Try to find the member we are instantiating. 4418 NamedDecl *Instantiation = 0; 4419 NamedDecl *InstantiatedFrom = 0; 4420 MemberSpecializationInfo *MSInfo = 0; 4421 4422 if (Previous.empty()) { 4423 // Nowhere to look anyway. 4424 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { 4425 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4426 I != E; ++I) { 4427 NamedDecl *D = (*I)->getUnderlyingDecl(); 4428 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 4429 if (Context.hasSameType(Function->getType(), Method->getType())) { 4430 Instantiation = Method; 4431 InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); 4432 MSInfo = Method->getMemberSpecializationInfo(); 4433 break; 4434 } 4435 } 4436 } 4437 } else if (isa<VarDecl>(Member)) { 4438 VarDecl *PrevVar; 4439 if (Previous.isSingleResult() && 4440 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) 4441 if (PrevVar->isStaticDataMember()) { 4442 Instantiation = PrevVar; 4443 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); 4444 MSInfo = PrevVar->getMemberSpecializationInfo(); 4445 } 4446 } else if (isa<RecordDecl>(Member)) { 4447 CXXRecordDecl *PrevRecord; 4448 if (Previous.isSingleResult() && 4449 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { 4450 Instantiation = PrevRecord; 4451 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); 4452 MSInfo = PrevRecord->getMemberSpecializationInfo(); 4453 } 4454 } 4455 4456 if (!Instantiation) { 4457 // There is no previous declaration that matches. Since member 4458 // specializations are always out-of-line, the caller will complain about 4459 // this mismatch later. 4460 return false; 4461 } 4462 4463 // If this is a friend, just bail out here before we start turning 4464 // things into explicit specializations. 4465 if (Member->getFriendObjectKind() != Decl::FOK_None) { 4466 // Preserve instantiation information. 4467 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) { 4468 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction( 4469 cast<CXXMethodDecl>(InstantiatedFrom), 4470 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind()); 4471 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) { 4472 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4473 cast<CXXRecordDecl>(InstantiatedFrom), 4474 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind()); 4475 } 4476 4477 Previous.clear(); 4478 Previous.addDecl(Instantiation); 4479 return false; 4480 } 4481 4482 // Make sure that this is a specialization of a member. 4483 if (!InstantiatedFrom) { 4484 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) 4485 << Member; 4486 Diag(Instantiation->getLocation(), diag::note_specialized_decl); 4487 return true; 4488 } 4489 4490 // C++ [temp.expl.spec]p6: 4491 // If a template, a member template or the member of a class template is 4492 // explicitly specialized then that spe- cialization shall be declared 4493 // before the first use of that specialization that would cause an implicit 4494 // instantiation to take place, in every translation unit in which such a 4495 // use occurs; no diagnostic is required. 4496 assert(MSInfo && "Member specialization info missing?"); 4497 4498 bool HasNoEffect = false; 4499 if (CheckSpecializationInstantiationRedecl(Member->getLocation(), 4500 TSK_ExplicitSpecialization, 4501 Instantiation, 4502 MSInfo->getTemplateSpecializationKind(), 4503 MSInfo->getPointOfInstantiation(), 4504 HasNoEffect)) 4505 return true; 4506 4507 // Check the scope of this explicit specialization. 4508 if (CheckTemplateSpecializationScope(*this, 4509 InstantiatedFrom, 4510 Instantiation, Member->getLocation(), 4511 false)) 4512 return true; 4513 4514 // Note that this is an explicit instantiation of a member. 4515 // the original declaration to note that it is an explicit specialization 4516 // (if it was previously an implicit instantiation). This latter step 4517 // makes bookkeeping easier. 4518 if (isa<FunctionDecl>(Member)) { 4519 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); 4520 if (InstantiationFunction->getTemplateSpecializationKind() == 4521 TSK_ImplicitInstantiation) { 4522 InstantiationFunction->setTemplateSpecializationKind( 4523 TSK_ExplicitSpecialization); 4524 InstantiationFunction->setLocation(Member->getLocation()); 4525 } 4526 4527 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( 4528 cast<CXXMethodDecl>(InstantiatedFrom), 4529 TSK_ExplicitSpecialization); 4530 } else if (isa<VarDecl>(Member)) { 4531 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); 4532 if (InstantiationVar->getTemplateSpecializationKind() == 4533 TSK_ImplicitInstantiation) { 4534 InstantiationVar->setTemplateSpecializationKind( 4535 TSK_ExplicitSpecialization); 4536 InstantiationVar->setLocation(Member->getLocation()); 4537 } 4538 4539 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), 4540 cast<VarDecl>(InstantiatedFrom), 4541 TSK_ExplicitSpecialization); 4542 } else { 4543 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain"); 4544 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); 4545 if (InstantiationClass->getTemplateSpecializationKind() == 4546 TSK_ImplicitInstantiation) { 4547 InstantiationClass->setTemplateSpecializationKind( 4548 TSK_ExplicitSpecialization); 4549 InstantiationClass->setLocation(Member->getLocation()); 4550 } 4551 4552 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4553 cast<CXXRecordDecl>(InstantiatedFrom), 4554 TSK_ExplicitSpecialization); 4555 } 4556 4557 // Save the caller the trouble of having to figure out which declaration 4558 // this specialization matches. 4559 Previous.clear(); 4560 Previous.addDecl(Instantiation); 4561 return false; 4562} 4563 4564/// \brief Check the scope of an explicit instantiation. 4565/// 4566/// \returns true if a serious error occurs, false otherwise. 4567static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, 4568 SourceLocation InstLoc, 4569 bool WasQualifiedName) { 4570 DeclContext *ExpectedContext 4571 = D->getDeclContext()->getEnclosingNamespaceContext()->getLookupContext(); 4572 DeclContext *CurContext = S.CurContext->getLookupContext(); 4573 4574 if (CurContext->isRecord()) { 4575 S.Diag(InstLoc, diag::err_explicit_instantiation_in_class) 4576 << D; 4577 return true; 4578 } 4579 4580 // C++0x [temp.explicit]p2: 4581 // An explicit instantiation shall appear in an enclosing namespace of its 4582 // template. 4583 // 4584 // This is DR275, which we do not retroactively apply to C++98/03. 4585 if (S.getLangOptions().CPlusPlus0x && 4586 !CurContext->Encloses(ExpectedContext)) { 4587 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(ExpectedContext)) 4588 S.Diag(InstLoc, 4589 S.getLangOptions().CPlusPlus0x? 4590 diag::err_explicit_instantiation_out_of_scope 4591 : diag::warn_explicit_instantiation_out_of_scope_0x) 4592 << D << NS; 4593 else 4594 S.Diag(InstLoc, 4595 S.getLangOptions().CPlusPlus0x? 4596 diag::err_explicit_instantiation_must_be_global 4597 : diag::warn_explicit_instantiation_out_of_scope_0x) 4598 << D; 4599 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4600 return false; 4601 } 4602 4603 // C++0x [temp.explicit]p2: 4604 // If the name declared in the explicit instantiation is an unqualified 4605 // name, the explicit instantiation shall appear in the namespace where 4606 // its template is declared or, if that namespace is inline (7.3.1), any 4607 // namespace from its enclosing namespace set. 4608 if (WasQualifiedName) 4609 return false; 4610 4611 if (CurContext->Equals(ExpectedContext)) 4612 return false; 4613 4614 S.Diag(InstLoc, 4615 S.getLangOptions().CPlusPlus0x? 4616 diag::err_explicit_instantiation_unqualified_wrong_namespace 4617 : diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x) 4618 << D << ExpectedContext; 4619 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4620 return false; 4621} 4622 4623/// \brief Determine whether the given scope specifier has a template-id in it. 4624static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { 4625 if (!SS.isSet()) 4626 return false; 4627 4628 // C++0x [temp.explicit]p2: 4629 // If the explicit instantiation is for a member function, a member class 4630 // or a static data member of a class template specialization, the name of 4631 // the class template specialization in the qualified-id for the member 4632 // name shall be a simple-template-id. 4633 // 4634 // C++98 has the same restriction, just worded differently. 4635 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 4636 NNS; NNS = NNS->getPrefix()) 4637 if (Type *T = NNS->getAsType()) 4638 if (isa<TemplateSpecializationType>(T)) 4639 return true; 4640 4641 return false; 4642} 4643 4644// Explicit instantiation of a class template specialization 4645Sema::DeclResult 4646Sema::ActOnExplicitInstantiation(Scope *S, 4647 SourceLocation ExternLoc, 4648 SourceLocation TemplateLoc, 4649 unsigned TagSpec, 4650 SourceLocation KWLoc, 4651 const CXXScopeSpec &SS, 4652 TemplateTy TemplateD, 4653 SourceLocation TemplateNameLoc, 4654 SourceLocation LAngleLoc, 4655 ASTTemplateArgsPtr TemplateArgsIn, 4656 SourceLocation RAngleLoc, 4657 AttributeList *Attr) { 4658 // Find the class template we're specializing 4659 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 4660 ClassTemplateDecl *ClassTemplate 4661 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); 4662 4663 // Check that the specialization uses the same tag kind as the 4664 // original template. 4665 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 4666 assert(Kind != TTK_Enum && 4667 "Invalid enum tag in class template explicit instantiation!"); 4668 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 4669 Kind, KWLoc, 4670 *ClassTemplate->getIdentifier())) { 4671 Diag(KWLoc, diag::err_use_with_wrong_tag) 4672 << ClassTemplate 4673 << FixItHint::CreateReplacement(KWLoc, 4674 ClassTemplate->getTemplatedDecl()->getKindName()); 4675 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 4676 diag::note_previous_use); 4677 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 4678 } 4679 4680 // C++0x [temp.explicit]p2: 4681 // There are two forms of explicit instantiation: an explicit instantiation 4682 // definition and an explicit instantiation declaration. An explicit 4683 // instantiation declaration begins with the extern keyword. [...] 4684 TemplateSpecializationKind TSK 4685 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4686 : TSK_ExplicitInstantiationDeclaration; 4687 4688 // Translate the parser's template argument list in our AST format. 4689 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 4690 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 4691 4692 // Check that the template argument list is well-formed for this 4693 // template. 4694 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 4695 TemplateArgs.size()); 4696 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 4697 TemplateArgs, false, Converted)) 4698 return true; 4699 4700 assert((Converted.structuredSize() == 4701 ClassTemplate->getTemplateParameters()->size()) && 4702 "Converted template argument list is too short!"); 4703 4704 // Find the class template specialization declaration that 4705 // corresponds to these arguments. 4706 llvm::FoldingSetNodeID ID; 4707 ClassTemplateSpecializationDecl::Profile(ID, 4708 Converted.getFlatArguments(), 4709 Converted.flatSize(), 4710 Context); 4711 void *InsertPos = 0; 4712 ClassTemplateSpecializationDecl *PrevDecl 4713 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 4714 4715 TemplateSpecializationKind PrevDecl_TSK 4716 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared; 4717 4718 // C++0x [temp.explicit]p2: 4719 // [...] An explicit instantiation shall appear in an enclosing 4720 // namespace of its template. [...] 4721 // 4722 // This is C++ DR 275. 4723 if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, 4724 SS.isSet())) 4725 return true; 4726 4727 ClassTemplateSpecializationDecl *Specialization = 0; 4728 4729 bool ReusedDecl = false; 4730 bool HasNoEffect = false; 4731 if (PrevDecl) { 4732 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, 4733 PrevDecl, PrevDecl_TSK, 4734 PrevDecl->getPointOfInstantiation(), 4735 HasNoEffect)) 4736 return DeclPtrTy::make(PrevDecl); 4737 4738 // Even though HasNoEffect == true means that this explicit instantiation 4739 // has no effect on semantics, we go on to put its syntax in the AST. 4740 4741 if (PrevDecl_TSK == TSK_ImplicitInstantiation || 4742 PrevDecl_TSK == TSK_Undeclared) { 4743 // Since the only prior class template specialization with these 4744 // arguments was referenced but not declared, reuse that 4745 // declaration node as our own, updating the source location 4746 // for the template name to reflect our new declaration. 4747 // (Other source locations will be updated later.) 4748 Specialization = PrevDecl; 4749 Specialization->setLocation(TemplateNameLoc); 4750 PrevDecl = 0; 4751 ReusedDecl = true; 4752 } 4753 } 4754 4755 if (!Specialization) { 4756 // Create a new class template specialization declaration node for 4757 // this explicit specialization. 4758 Specialization 4759 = ClassTemplateSpecializationDecl::Create(Context, Kind, 4760 ClassTemplate->getDeclContext(), 4761 TemplateNameLoc, 4762 ClassTemplate, 4763 Converted, PrevDecl); 4764 SetNestedNameSpecifier(Specialization, SS); 4765 4766 if (!HasNoEffect) { 4767 if (PrevDecl) { 4768 // Remove the previous declaration from the folding set, since we want 4769 // to introduce a new declaration. 4770 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 4771 ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 4772 } 4773 // Insert the new specialization. 4774 ClassTemplate->getSpecializations().InsertNode(Specialization, InsertPos); 4775 } 4776 } 4777 4778 // Build the fully-sugared type for this explicit instantiation as 4779 // the user wrote in the explicit instantiation itself. This means 4780 // that we'll pretty-print the type retrieved from the 4781 // specialization's declaration the way that the user actually wrote 4782 // the explicit instantiation, rather than formatting the name based 4783 // on the "canonical" representation used to store the template 4784 // arguments in the specialization. 4785 TypeSourceInfo *WrittenTy 4786 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 4787 TemplateArgs, 4788 Context.getTypeDeclType(Specialization)); 4789 Specialization->setTypeAsWritten(WrittenTy); 4790 TemplateArgsIn.release(); 4791 4792 // Set source locations for keywords. 4793 Specialization->setExternLoc(ExternLoc); 4794 Specialization->setTemplateKeywordLoc(TemplateLoc); 4795 4796 // Add the explicit instantiation into its lexical context. However, 4797 // since explicit instantiations are never found by name lookup, we 4798 // just put it into the declaration context directly. 4799 Specialization->setLexicalDeclContext(CurContext); 4800 CurContext->addDecl(Specialization); 4801 4802 // Syntax is now OK, so return if it has no other effect on semantics. 4803 if (HasNoEffect) { 4804 // Set the template specialization kind. 4805 Specialization->setTemplateSpecializationKind(TSK); 4806 return DeclPtrTy::make(Specialization); 4807 } 4808 4809 // C++ [temp.explicit]p3: 4810 // A definition of a class template or class member template 4811 // shall be in scope at the point of the explicit instantiation of 4812 // the class template or class member template. 4813 // 4814 // This check comes when we actually try to perform the 4815 // instantiation. 4816 ClassTemplateSpecializationDecl *Def 4817 = cast_or_null<ClassTemplateSpecializationDecl>( 4818 Specialization->getDefinition()); 4819 if (!Def) 4820 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); 4821 else if (TSK == TSK_ExplicitInstantiationDefinition) { 4822 MarkVTableUsed(TemplateNameLoc, Specialization, true); 4823 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation()); 4824 } 4825 4826 // Instantiate the members of this class template specialization. 4827 Def = cast_or_null<ClassTemplateSpecializationDecl>( 4828 Specialization->getDefinition()); 4829 if (Def) { 4830 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind(); 4831 4832 // Fix a TSK_ExplicitInstantiationDeclaration followed by a 4833 // TSK_ExplicitInstantiationDefinition 4834 if (Old_TSK == TSK_ExplicitInstantiationDeclaration && 4835 TSK == TSK_ExplicitInstantiationDefinition) 4836 Def->setTemplateSpecializationKind(TSK); 4837 4838 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); 4839 } 4840 4841 // Set the template specialization kind. 4842 Specialization->setTemplateSpecializationKind(TSK); 4843 return DeclPtrTy::make(Specialization); 4844} 4845 4846// Explicit instantiation of a member class of a class template. 4847Sema::DeclResult 4848Sema::ActOnExplicitInstantiation(Scope *S, 4849 SourceLocation ExternLoc, 4850 SourceLocation TemplateLoc, 4851 unsigned TagSpec, 4852 SourceLocation KWLoc, 4853 CXXScopeSpec &SS, 4854 IdentifierInfo *Name, 4855 SourceLocation NameLoc, 4856 AttributeList *Attr) { 4857 4858 bool Owned = false; 4859 bool IsDependent = false; 4860 DeclPtrTy TagD = ActOnTag(S, TagSpec, Action::TUK_Reference, 4861 KWLoc, SS, Name, NameLoc, Attr, AS_none, 4862 MultiTemplateParamsArg(*this, 0, 0), 4863 Owned, IsDependent); 4864 assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); 4865 4866 if (!TagD) 4867 return true; 4868 4869 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4870 if (Tag->isEnum()) { 4871 Diag(TemplateLoc, diag::err_explicit_instantiation_enum) 4872 << Context.getTypeDeclType(Tag); 4873 return true; 4874 } 4875 4876 if (Tag->isInvalidDecl()) 4877 return true; 4878 4879 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); 4880 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); 4881 if (!Pattern) { 4882 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) 4883 << Context.getTypeDeclType(Record); 4884 Diag(Record->getLocation(), diag::note_nontemplate_decl_here); 4885 return true; 4886 } 4887 4888 // C++0x [temp.explicit]p2: 4889 // If the explicit instantiation is for a class or member class, the 4890 // elaborated-type-specifier in the declaration shall include a 4891 // simple-template-id. 4892 // 4893 // C++98 has the same restriction, just worded differently. 4894 if (!ScopeSpecifierHasTemplateId(SS)) 4895 Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id) 4896 << Record << SS.getRange(); 4897 4898 // C++0x [temp.explicit]p2: 4899 // There are two forms of explicit instantiation: an explicit instantiation 4900 // definition and an explicit instantiation declaration. An explicit 4901 // instantiation declaration begins with the extern keyword. [...] 4902 TemplateSpecializationKind TSK 4903 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4904 : TSK_ExplicitInstantiationDeclaration; 4905 4906 // C++0x [temp.explicit]p2: 4907 // [...] An explicit instantiation shall appear in an enclosing 4908 // namespace of its template. [...] 4909 // 4910 // This is C++ DR 275. 4911 CheckExplicitInstantiationScope(*this, Record, NameLoc, true); 4912 4913 // Verify that it is okay to explicitly instantiate here. 4914 CXXRecordDecl *PrevDecl 4915 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration()); 4916 if (!PrevDecl && Record->getDefinition()) 4917 PrevDecl = Record; 4918 if (PrevDecl) { 4919 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); 4920 bool HasNoEffect = false; 4921 assert(MSInfo && "No member specialization information?"); 4922 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, 4923 PrevDecl, 4924 MSInfo->getTemplateSpecializationKind(), 4925 MSInfo->getPointOfInstantiation(), 4926 HasNoEffect)) 4927 return true; 4928 if (HasNoEffect) 4929 return TagD; 4930 } 4931 4932 CXXRecordDecl *RecordDef 4933 = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4934 if (!RecordDef) { 4935 // C++ [temp.explicit]p3: 4936 // A definition of a member class of a class template shall be in scope 4937 // at the point of an explicit instantiation of the member class. 4938 CXXRecordDecl *Def 4939 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition()); 4940 if (!Def) { 4941 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) 4942 << 0 << Record->getDeclName() << Record->getDeclContext(); 4943 Diag(Pattern->getLocation(), diag::note_forward_declaration) 4944 << Pattern; 4945 return true; 4946 } else { 4947 if (InstantiateClass(NameLoc, Record, Def, 4948 getTemplateInstantiationArgs(Record), 4949 TSK)) 4950 return true; 4951 4952 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4953 if (!RecordDef) 4954 return true; 4955 } 4956 } 4957 4958 // Instantiate all of the members of the class. 4959 InstantiateClassMembers(NameLoc, RecordDef, 4960 getTemplateInstantiationArgs(Record), TSK); 4961 4962 if (TSK == TSK_ExplicitInstantiationDefinition) 4963 MarkVTableUsed(NameLoc, RecordDef, true); 4964 4965 // FIXME: We don't have any representation for explicit instantiations of 4966 // member classes. Such a representation is not needed for compilation, but it 4967 // should be available for clients that want to see all of the declarations in 4968 // the source code. 4969 return TagD; 4970} 4971 4972Sema::DeclResult Sema::ActOnExplicitInstantiation(Scope *S, 4973 SourceLocation ExternLoc, 4974 SourceLocation TemplateLoc, 4975 Declarator &D) { 4976 // Explicit instantiations always require a name. 4977 DeclarationName Name = GetNameForDeclarator(D); 4978 if (!Name) { 4979 if (!D.isInvalidType()) 4980 Diag(D.getDeclSpec().getSourceRange().getBegin(), 4981 diag::err_explicit_instantiation_requires_name) 4982 << D.getDeclSpec().getSourceRange() 4983 << D.getSourceRange(); 4984 4985 return true; 4986 } 4987 4988 // The scope passed in may not be a decl scope. Zip up the scope tree until 4989 // we find one that is. 4990 while ((S->getFlags() & Scope::DeclScope) == 0 || 4991 (S->getFlags() & Scope::TemplateParamScope) != 0) 4992 S = S->getParent(); 4993 4994 // Determine the type of the declaration. 4995 TypeSourceInfo *T = GetTypeForDeclarator(D, S); 4996 QualType R = T->getType(); 4997 if (R.isNull()) 4998 return true; 4999 5000 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 5001 // Cannot explicitly instantiate a typedef. 5002 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) 5003 << Name; 5004 return true; 5005 } 5006 5007 // C++0x [temp.explicit]p1: 5008 // [...] An explicit instantiation of a function template shall not use the 5009 // inline or constexpr specifiers. 5010 // Presumably, this also applies to member functions of class templates as 5011 // well. 5012 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x) 5013 Diag(D.getDeclSpec().getInlineSpecLoc(), 5014 diag::err_explicit_instantiation_inline) 5015 <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 5016 5017 // FIXME: check for constexpr specifier. 5018 5019 // C++0x [temp.explicit]p2: 5020 // There are two forms of explicit instantiation: an explicit instantiation 5021 // definition and an explicit instantiation declaration. An explicit 5022 // instantiation declaration begins with the extern keyword. [...] 5023 TemplateSpecializationKind TSK 5024 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 5025 : TSK_ExplicitInstantiationDeclaration; 5026 5027 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName); 5028 LookupParsedName(Previous, S, &D.getCXXScopeSpec()); 5029 5030 if (!R->isFunctionType()) { 5031 // C++ [temp.explicit]p1: 5032 // A [...] static data member of a class template can be explicitly 5033 // instantiated from the member definition associated with its class 5034 // template. 5035 if (Previous.isAmbiguous()) 5036 return true; 5037 5038 VarDecl *Prev = Previous.getAsSingle<VarDecl>(); 5039 if (!Prev || !Prev->isStaticDataMember()) { 5040 // We expect to see a data data member here. 5041 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) 5042 << Name; 5043 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 5044 P != PEnd; ++P) 5045 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); 5046 return true; 5047 } 5048 5049 if (!Prev->getInstantiatedFromStaticDataMember()) { 5050 // FIXME: Check for explicit specialization? 5051 Diag(D.getIdentifierLoc(), 5052 diag::err_explicit_instantiation_data_member_not_instantiated) 5053 << Prev; 5054 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); 5055 // FIXME: Can we provide a note showing where this was declared? 5056 return true; 5057 } 5058 5059 // C++0x [temp.explicit]p2: 5060 // If the explicit instantiation is for a member function, a member class 5061 // or a static data member of a class template specialization, the name of 5062 // the class template specialization in the qualified-id for the member 5063 // name shall be a simple-template-id. 5064 // 5065 // C++98 has the same restriction, just worded differently. 5066 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5067 Diag(D.getIdentifierLoc(), 5068 diag::ext_explicit_instantiation_without_qualified_id) 5069 << Prev << D.getCXXScopeSpec().getRange(); 5070 5071 // Check the scope of this explicit instantiation. 5072 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); 5073 5074 // Verify that it is okay to explicitly instantiate here. 5075 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); 5076 assert(MSInfo && "Missing static data member specialization info?"); 5077 bool HasNoEffect = false; 5078 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, 5079 MSInfo->getTemplateSpecializationKind(), 5080 MSInfo->getPointOfInstantiation(), 5081 HasNoEffect)) 5082 return true; 5083 if (HasNoEffect) 5084 return DeclPtrTy(); 5085 5086 // Instantiate static data member. 5087 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5088 if (TSK == TSK_ExplicitInstantiationDefinition) 5089 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev, false, 5090 /*DefinitionRequired=*/true); 5091 5092 // FIXME: Create an ExplicitInstantiation node? 5093 return DeclPtrTy(); 5094 } 5095 5096 // If the declarator is a template-id, translate the parser's template 5097 // argument list into our AST format. 5098 bool HasExplicitTemplateArgs = false; 5099 TemplateArgumentListInfo TemplateArgs; 5100 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 5101 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 5102 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 5103 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 5104 ASTTemplateArgsPtr TemplateArgsPtr(*this, 5105 TemplateId->getTemplateArgs(), 5106 TemplateId->NumArgs); 5107 translateTemplateArguments(TemplateArgsPtr, TemplateArgs); 5108 HasExplicitTemplateArgs = true; 5109 TemplateArgsPtr.release(); 5110 } 5111 5112 // C++ [temp.explicit]p1: 5113 // A [...] function [...] can be explicitly instantiated from its template. 5114 // A member function [...] of a class template can be explicitly 5115 // instantiated from the member definition associated with its class 5116 // template. 5117 UnresolvedSet<8> Matches; 5118 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 5119 P != PEnd; ++P) { 5120 NamedDecl *Prev = *P; 5121 if (!HasExplicitTemplateArgs) { 5122 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { 5123 if (Context.hasSameUnqualifiedType(Method->getType(), R)) { 5124 Matches.clear(); 5125 5126 Matches.addDecl(Method, P.getAccess()); 5127 if (Method->getTemplateSpecializationKind() == TSK_Undeclared) 5128 break; 5129 } 5130 } 5131 } 5132 5133 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); 5134 if (!FunTmpl) 5135 continue; 5136 5137 TemplateDeductionInfo Info(Context, D.getIdentifierLoc()); 5138 FunctionDecl *Specialization = 0; 5139 if (TemplateDeductionResult TDK 5140 = DeduceTemplateArguments(FunTmpl, 5141 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 5142 R, Specialization, Info)) { 5143 // FIXME: Keep track of almost-matches? 5144 (void)TDK; 5145 continue; 5146 } 5147 5148 Matches.addDecl(Specialization, P.getAccess()); 5149 } 5150 5151 // Find the most specialized function template specialization. 5152 UnresolvedSetIterator Result 5153 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, 5154 D.getIdentifierLoc(), 5155 PDiag(diag::err_explicit_instantiation_not_known) << Name, 5156 PDiag(diag::err_explicit_instantiation_ambiguous) << Name, 5157 PDiag(diag::note_explicit_instantiation_candidate)); 5158 5159 if (Result == Matches.end()) 5160 return true; 5161 5162 // Ignore access control bits, we don't need them for redeclaration checking. 5163 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 5164 5165 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { 5166 Diag(D.getIdentifierLoc(), 5167 diag::err_explicit_instantiation_member_function_not_instantiated) 5168 << Specialization 5169 << (Specialization->getTemplateSpecializationKind() == 5170 TSK_ExplicitSpecialization); 5171 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); 5172 return true; 5173 } 5174 5175 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration(); 5176 if (!PrevDecl && Specialization->isThisDeclarationADefinition()) 5177 PrevDecl = Specialization; 5178 5179 if (PrevDecl) { 5180 bool HasNoEffect = false; 5181 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, 5182 PrevDecl, 5183 PrevDecl->getTemplateSpecializationKind(), 5184 PrevDecl->getPointOfInstantiation(), 5185 HasNoEffect)) 5186 return true; 5187 5188 // FIXME: We may still want to build some representation of this 5189 // explicit specialization. 5190 if (HasNoEffect) 5191 return DeclPtrTy(); 5192 } 5193 5194 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5195 5196 if (TSK == TSK_ExplicitInstantiationDefinition) 5197 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization, 5198 false, /*DefinitionRequired=*/true); 5199 5200 // C++0x [temp.explicit]p2: 5201 // If the explicit instantiation is for a member function, a member class 5202 // or a static data member of a class template specialization, the name of 5203 // the class template specialization in the qualified-id for the member 5204 // name shall be a simple-template-id. 5205 // 5206 // C++98 has the same restriction, just worded differently. 5207 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); 5208 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && 5209 D.getCXXScopeSpec().isSet() && 5210 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5211 Diag(D.getIdentifierLoc(), 5212 diag::ext_explicit_instantiation_without_qualified_id) 5213 << Specialization << D.getCXXScopeSpec().getRange(); 5214 5215 CheckExplicitInstantiationScope(*this, 5216 FunTmpl? (NamedDecl *)FunTmpl 5217 : Specialization->getInstantiatedFromMemberFunction(), 5218 D.getIdentifierLoc(), 5219 D.getCXXScopeSpec().isSet()); 5220 5221 // FIXME: Create some kind of ExplicitInstantiationDecl here. 5222 return DeclPtrTy(); 5223} 5224 5225Sema::TypeResult 5226Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5227 const CXXScopeSpec &SS, IdentifierInfo *Name, 5228 SourceLocation TagLoc, SourceLocation NameLoc) { 5229 // This has to hold, because SS is expected to be defined. 5230 assert(Name && "Expected a name in a dependent tag"); 5231 5232 NestedNameSpecifier *NNS 5233 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5234 if (!NNS) 5235 return true; 5236 5237 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5238 5239 if (TUK == TUK_Declaration || TUK == TUK_Definition) { 5240 Diag(NameLoc, diag::err_dependent_tag_decl) 5241 << (TUK == TUK_Definition) << Kind << SS.getRange(); 5242 return true; 5243 } 5244 5245 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind); 5246 return Context.getDependentNameType(Kwd, NNS, Name).getAsOpaquePtr(); 5247} 5248 5249Sema::TypeResult 5250Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, 5251 const CXXScopeSpec &SS, const IdentifierInfo &II, 5252 SourceLocation IdLoc) { 5253 NestedNameSpecifier *NNS 5254 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5255 if (!NNS) 5256 return true; 5257 5258 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() && 5259 !getLangOptions().CPlusPlus0x) 5260 Diag(TypenameLoc, diag::ext_typename_outside_of_template) 5261 << FixItHint::CreateRemoval(TypenameLoc); 5262 5263 QualType T = CheckTypenameType(ETK_Typename, NNS, II, 5264 TypenameLoc, SS.getRange(), IdLoc); 5265 if (T.isNull()) 5266 return true; 5267 5268 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); 5269 if (isa<DependentNameType>(T)) { 5270 DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc()); 5271 TL.setKeywordLoc(TypenameLoc); 5272 TL.setQualifierRange(SS.getRange()); 5273 TL.setNameLoc(IdLoc); 5274 } else { 5275 ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc()); 5276 TL.setKeywordLoc(TypenameLoc); 5277 TL.setQualifierRange(SS.getRange()); 5278 cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc); 5279 } 5280 5281 return CreateLocInfoType(T, TSI).getAsOpaquePtr(); 5282} 5283 5284Sema::TypeResult 5285Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, 5286 const CXXScopeSpec &SS, SourceLocation TemplateLoc, 5287 TypeTy *Ty) { 5288 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() && 5289 !getLangOptions().CPlusPlus0x) 5290 Diag(TypenameLoc, diag::ext_typename_outside_of_template) 5291 << FixItHint::CreateRemoval(TypenameLoc); 5292 5293 TypeSourceInfo *InnerTSI = 0; 5294 QualType T = GetTypeFromParser(Ty, &InnerTSI); 5295 NestedNameSpecifier *NNS 5296 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5297 5298 assert(isa<TemplateSpecializationType>(T) && 5299 "Expected a template specialization type"); 5300 5301 if (computeDeclContext(SS, false)) { 5302 // If we can compute a declaration context, then the "typename" 5303 // keyword was superfluous. Just build an ElaboratedType to keep 5304 // track of the nested-name-specifier. 5305 5306 // Push the inner type, preserving its source locations if possible. 5307 TypeLocBuilder Builder; 5308 if (InnerTSI) 5309 Builder.pushFullCopy(InnerTSI->getTypeLoc()); 5310 else 5311 Builder.push<TemplateSpecializationTypeLoc>(T).initialize(TemplateLoc); 5312 5313 T = Context.getElaboratedType(ETK_Typename, NNS, T); 5314 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T); 5315 TL.setKeywordLoc(TypenameLoc); 5316 TL.setQualifierRange(SS.getRange()); 5317 5318 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T); 5319 return CreateLocInfoType(T, TSI).getAsOpaquePtr(); 5320 } 5321 5322 // TODO: it's really silly that we make a template specialization 5323 // type earlier only to drop it again here. 5324 TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T); 5325 DependentTemplateName *DTN = 5326 TST->getTemplateName().getAsDependentTemplateName(); 5327 assert(DTN && "dependent template has non-dependent name?"); 5328 T = Context.getDependentTemplateSpecializationType(ETK_Typename, NNS, 5329 DTN->getIdentifier(), 5330 TST->getNumArgs(), 5331 TST->getArgs()); 5332 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); 5333 DependentTemplateSpecializationTypeLoc TL = 5334 cast<DependentTemplateSpecializationTypeLoc>(TSI->getTypeLoc()); 5335 if (InnerTSI) { 5336 TemplateSpecializationTypeLoc TSTL = 5337 cast<TemplateSpecializationTypeLoc>(InnerTSI->getTypeLoc()); 5338 TL.setLAngleLoc(TSTL.getLAngleLoc()); 5339 TL.setRAngleLoc(TSTL.getRAngleLoc()); 5340 for (unsigned I = 0, E = TST->getNumArgs(); I != E; ++I) 5341 TL.setArgLocInfo(I, TSTL.getArgLocInfo(I)); 5342 } else { 5343 TL.initializeLocal(SourceLocation()); 5344 } 5345 TL.setKeywordLoc(TypenameLoc); 5346 TL.setQualifierRange(SS.getRange()); 5347 return CreateLocInfoType(T, TSI).getAsOpaquePtr(); 5348} 5349 5350/// \brief Build the type that describes a C++ typename specifier, 5351/// e.g., "typename T::type". 5352QualType 5353Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword, 5354 NestedNameSpecifier *NNS, const IdentifierInfo &II, 5355 SourceLocation KeywordLoc, SourceRange NNSRange, 5356 SourceLocation IILoc) { 5357 CXXScopeSpec SS; 5358 SS.setScopeRep(NNS); 5359 SS.setRange(NNSRange); 5360 5361 DeclContext *Ctx = computeDeclContext(SS); 5362 if (!Ctx) { 5363 // If the nested-name-specifier is dependent and couldn't be 5364 // resolved to a type, build a typename type. 5365 assert(NNS->isDependent()); 5366 return Context.getDependentNameType(Keyword, NNS, &II); 5367 } 5368 5369 // If the nested-name-specifier refers to the current instantiation, 5370 // the "typename" keyword itself is superfluous. In C++03, the 5371 // program is actually ill-formed. However, DR 382 (in C++0x CD1) 5372 // allows such extraneous "typename" keywords, and we retroactively 5373 // apply this DR to C++03 code with only a warning. In any case we continue. 5374 5375 if (RequireCompleteDeclContext(SS, Ctx)) 5376 return QualType(); 5377 5378 DeclarationName Name(&II); 5379 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName); 5380 LookupQualifiedName(Result, Ctx); 5381 unsigned DiagID = 0; 5382 Decl *Referenced = 0; 5383 switch (Result.getResultKind()) { 5384 case LookupResult::NotFound: 5385 DiagID = diag::err_typename_nested_not_found; 5386 break; 5387 5388 case LookupResult::NotFoundInCurrentInstantiation: 5389 // Okay, it's a member of an unknown instantiation. 5390 return Context.getDependentNameType(Keyword, NNS, &II); 5391 5392 case LookupResult::Found: 5393 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { 5394 // We found a type. Build an ElaboratedType, since the 5395 // typename-specifier was just sugar. 5396 return Context.getElaboratedType(ETK_Typename, NNS, 5397 Context.getTypeDeclType(Type)); 5398 } 5399 5400 DiagID = diag::err_typename_nested_not_type; 5401 Referenced = Result.getFoundDecl(); 5402 break; 5403 5404 case LookupResult::FoundUnresolvedValue: 5405 llvm_unreachable("unresolved using decl in non-dependent context"); 5406 return QualType(); 5407 5408 case LookupResult::FoundOverloaded: 5409 DiagID = diag::err_typename_nested_not_type; 5410 Referenced = *Result.begin(); 5411 break; 5412 5413 case LookupResult::Ambiguous: 5414 return QualType(); 5415 } 5416 5417 // If we get here, it's because name lookup did not find a 5418 // type. Emit an appropriate diagnostic and return an error. 5419 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(), 5420 IILoc); 5421 Diag(IILoc, DiagID) << FullRange << Name << Ctx; 5422 if (Referenced) 5423 Diag(Referenced->getLocation(), diag::note_typename_refers_here) 5424 << Name; 5425 return QualType(); 5426} 5427 5428namespace { 5429 // See Sema::RebuildTypeInCurrentInstantiation 5430 class CurrentInstantiationRebuilder 5431 : public TreeTransform<CurrentInstantiationRebuilder> { 5432 SourceLocation Loc; 5433 DeclarationName Entity; 5434 5435 public: 5436 typedef TreeTransform<CurrentInstantiationRebuilder> inherited; 5437 5438 CurrentInstantiationRebuilder(Sema &SemaRef, 5439 SourceLocation Loc, 5440 DeclarationName Entity) 5441 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), 5442 Loc(Loc), Entity(Entity) { } 5443 5444 /// \brief Determine whether the given type \p T has already been 5445 /// transformed. 5446 /// 5447 /// For the purposes of type reconstruction, a type has already been 5448 /// transformed if it is NULL or if it is not dependent. 5449 bool AlreadyTransformed(QualType T) { 5450 return T.isNull() || !T->isDependentType(); 5451 } 5452 5453 /// \brief Returns the location of the entity whose type is being 5454 /// rebuilt. 5455 SourceLocation getBaseLocation() { return Loc; } 5456 5457 /// \brief Returns the name of the entity whose type is being rebuilt. 5458 DeclarationName getBaseEntity() { return Entity; } 5459 5460 /// \brief Sets the "base" location and entity when that 5461 /// information is known based on another transformation. 5462 void setBase(SourceLocation Loc, DeclarationName Entity) { 5463 this->Loc = Loc; 5464 this->Entity = Entity; 5465 } 5466 5467 /// \brief Transforms an expression by returning the expression itself 5468 /// (an identity function). 5469 /// 5470 /// FIXME: This is completely unsafe; we will need to actually clone the 5471 /// expressions. 5472 Sema::OwningExprResult TransformExpr(Expr *E) { 5473 return getSema().Owned(E->Retain()); 5474 } 5475 }; 5476} 5477 5478/// \brief Rebuilds a type within the context of the current instantiation. 5479/// 5480/// The type \p T is part of the type of an out-of-line member definition of 5481/// a class template (or class template partial specialization) that was parsed 5482/// and constructed before we entered the scope of the class template (or 5483/// partial specialization thereof). This routine will rebuild that type now 5484/// that we have entered the declarator's scope, which may produce different 5485/// canonical types, e.g., 5486/// 5487/// \code 5488/// template<typename T> 5489/// struct X { 5490/// typedef T* pointer; 5491/// pointer data(); 5492/// }; 5493/// 5494/// template<typename T> 5495/// typename X<T>::pointer X<T>::data() { ... } 5496/// \endcode 5497/// 5498/// Here, the type "typename X<T>::pointer" will be created as a DependentNameType, 5499/// since we do not know that we can look into X<T> when we parsed the type. 5500/// This function will rebuild the type, performing the lookup of "pointer" 5501/// in X<T> and returning an ElaboratedType whose canonical type is the same 5502/// as the canonical type of T*, allowing the return types of the out-of-line 5503/// definition and the declaration to match. 5504TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T, 5505 SourceLocation Loc, 5506 DeclarationName Name) { 5507 if (!T || !T->getType()->isDependentType()) 5508 return T; 5509 5510 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); 5511 return Rebuilder.TransformType(T); 5512} 5513 5514bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) { 5515 if (SS.isInvalid()) return true; 5516 5517 NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5518 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(), 5519 DeclarationName()); 5520 NestedNameSpecifier *Rebuilt = 5521 Rebuilder.TransformNestedNameSpecifier(NNS, SS.getRange()); 5522 if (!Rebuilt) return true; 5523 5524 SS.setScopeRep(Rebuilt); 5525 return false; 5526} 5527 5528/// \brief Produces a formatted string that describes the binding of 5529/// template parameters to template arguments. 5530std::string 5531Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5532 const TemplateArgumentList &Args) { 5533 // FIXME: For variadic templates, we'll need to get the structured list. 5534 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(), 5535 Args.flat_size()); 5536} 5537 5538std::string 5539Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5540 const TemplateArgument *Args, 5541 unsigned NumArgs) { 5542 std::string Result; 5543 5544 if (!Params || Params->size() == 0 || NumArgs == 0) 5545 return Result; 5546 5547 for (unsigned I = 0, N = Params->size(); I != N; ++I) { 5548 if (I >= NumArgs) 5549 break; 5550 5551 if (I == 0) 5552 Result += "[with "; 5553 else 5554 Result += ", "; 5555 5556 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { 5557 Result += Id->getName(); 5558 } else { 5559 Result += '$'; 5560 Result += llvm::utostr(I); 5561 } 5562 5563 Result += " = "; 5564 5565 switch (Args[I].getKind()) { 5566 case TemplateArgument::Null: 5567 Result += "<no value>"; 5568 break; 5569 5570 case TemplateArgument::Type: { 5571 std::string TypeStr; 5572 Args[I].getAsType().getAsStringInternal(TypeStr, 5573 Context.PrintingPolicy); 5574 Result += TypeStr; 5575 break; 5576 } 5577 5578 case TemplateArgument::Declaration: { 5579 bool Unnamed = true; 5580 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) { 5581 if (ND->getDeclName()) { 5582 Unnamed = false; 5583 Result += ND->getNameAsString(); 5584 } 5585 } 5586 5587 if (Unnamed) { 5588 Result += "<anonymous>"; 5589 } 5590 break; 5591 } 5592 5593 case TemplateArgument::Template: { 5594 std::string Str; 5595 llvm::raw_string_ostream OS(Str); 5596 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy); 5597 Result += OS.str(); 5598 break; 5599 } 5600 5601 case TemplateArgument::Integral: { 5602 Result += Args[I].getAsIntegral()->toString(10); 5603 break; 5604 } 5605 5606 case TemplateArgument::Expression: { 5607 // FIXME: This is non-optimal, since we're regurgitating the 5608 // expression we were given. 5609 std::string Str; 5610 { 5611 llvm::raw_string_ostream OS(Str); 5612 Args[I].getAsExpr()->printPretty(OS, Context, 0, 5613 Context.PrintingPolicy); 5614 } 5615 Result += Str; 5616 break; 5617 } 5618 5619 case TemplateArgument::Pack: 5620 // FIXME: Format template argument packs 5621 Result += "<template argument pack>"; 5622 break; 5623 } 5624 } 5625 5626 Result += ']'; 5627 return Result; 5628} 5629