SemaTemplate.cpp revision 2d88708cbe4e4ec5e04e4acb6bd7f5be68557379
1//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/ 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7//===----------------------------------------------------------------------===/ 8// 9// This file implements semantic analysis for C++ templates. 10//===----------------------------------------------------------------------===/ 11 12#include "clang/Sema/SemaInternal.h" 13#include "clang/Sema/Lookup.h" 14#include "clang/Sema/Scope.h" 15#include "clang/Sema/Template.h" 16#include "clang/Sema/TemplateDeduction.h" 17#include "TreeTransform.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/Expr.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/AST/DeclFriend.h" 22#include "clang/AST/DeclTemplate.h" 23#include "clang/Sema/DeclSpec.h" 24#include "clang/Sema/ParsedTemplate.h" 25#include "clang/Basic/LangOptions.h" 26#include "clang/Basic/PartialDiagnostic.h" 27#include "llvm/ADT/StringExtras.h" 28using namespace clang; 29using namespace sema; 30 31/// \brief Determine whether the declaration found is acceptable as the name 32/// of a template and, if so, return that template declaration. Otherwise, 33/// returns NULL. 34static NamedDecl *isAcceptableTemplateName(ASTContext &Context, 35 NamedDecl *Orig) { 36 NamedDecl *D = Orig->getUnderlyingDecl(); 37 38 if (isa<TemplateDecl>(D)) 39 return Orig; 40 41 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) { 42 // C++ [temp.local]p1: 43 // Like normal (non-template) classes, class templates have an 44 // injected-class-name (Clause 9). The injected-class-name 45 // can be used with or without a template-argument-list. When 46 // it is used without a template-argument-list, it is 47 // equivalent to the injected-class-name followed by the 48 // template-parameters of the class template enclosed in 49 // <>. When it is used with a template-argument-list, it 50 // refers to the specified class template specialization, 51 // which could be the current specialization or another 52 // specialization. 53 if (Record->isInjectedClassName()) { 54 Record = cast<CXXRecordDecl>(Record->getDeclContext()); 55 if (Record->getDescribedClassTemplate()) 56 return Record->getDescribedClassTemplate(); 57 58 if (ClassTemplateSpecializationDecl *Spec 59 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) 60 return Spec->getSpecializedTemplate(); 61 } 62 63 return 0; 64 } 65 66 return 0; 67} 68 69static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) { 70 // The set of class templates we've already seen. 71 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates; 72 LookupResult::Filter filter = R.makeFilter(); 73 while (filter.hasNext()) { 74 NamedDecl *Orig = filter.next(); 75 NamedDecl *Repl = isAcceptableTemplateName(C, Orig); 76 if (!Repl) 77 filter.erase(); 78 else if (Repl != Orig) { 79 80 // C++ [temp.local]p3: 81 // A lookup that finds an injected-class-name (10.2) can result in an 82 // ambiguity in certain cases (for example, if it is found in more than 83 // one base class). If all of the injected-class-names that are found 84 // refer to specializations of the same class template, and if the name 85 // is followed by a template-argument-list, the reference refers to the 86 // class template itself and not a specialization thereof, and is not 87 // ambiguous. 88 // 89 // FIXME: Will we eventually have to do the same for alias templates? 90 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl)) 91 if (!ClassTemplates.insert(ClassTmpl)) { 92 filter.erase(); 93 continue; 94 } 95 96 // FIXME: we promote access to public here as a workaround to 97 // the fact that LookupResult doesn't let us remember that we 98 // found this template through a particular injected class name, 99 // which means we end up doing nasty things to the invariants. 100 // Pretending that access is public is *much* safer. 101 filter.replace(Repl, AS_public); 102 } 103 } 104 filter.done(); 105} 106 107TemplateNameKind Sema::isTemplateName(Scope *S, 108 CXXScopeSpec &SS, 109 bool hasTemplateKeyword, 110 UnqualifiedId &Name, 111 ParsedType ObjectTypePtr, 112 bool EnteringContext, 113 TemplateTy &TemplateResult, 114 bool &MemberOfUnknownSpecialization) { 115 assert(getLangOptions().CPlusPlus && "No template names in C!"); 116 117 DeclarationName TName; 118 MemberOfUnknownSpecialization = false; 119 120 switch (Name.getKind()) { 121 case UnqualifiedId::IK_Identifier: 122 TName = DeclarationName(Name.Identifier); 123 break; 124 125 case UnqualifiedId::IK_OperatorFunctionId: 126 TName = Context.DeclarationNames.getCXXOperatorName( 127 Name.OperatorFunctionId.Operator); 128 break; 129 130 case UnqualifiedId::IK_LiteralOperatorId: 131 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier); 132 break; 133 134 default: 135 return TNK_Non_template; 136 } 137 138 QualType ObjectType = ObjectTypePtr.get(); 139 140 LookupResult R(*this, TName, Name.getSourceRange().getBegin(), 141 LookupOrdinaryName); 142 LookupTemplateName(R, S, SS, ObjectType, EnteringContext, 143 MemberOfUnknownSpecialization); 144 if (R.empty() || R.isAmbiguous()) { 145 R.suppressDiagnostics(); 146 return TNK_Non_template; 147 } 148 149 TemplateName Template; 150 TemplateNameKind TemplateKind; 151 152 unsigned ResultCount = R.end() - R.begin(); 153 if (ResultCount > 1) { 154 // We assume that we'll preserve the qualifier from a function 155 // template name in other ways. 156 Template = Context.getOverloadedTemplateName(R.begin(), R.end()); 157 TemplateKind = TNK_Function_template; 158 159 // We'll do this lookup again later. 160 R.suppressDiagnostics(); 161 } else { 162 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl()); 163 164 if (SS.isSet() && !SS.isInvalid()) { 165 NestedNameSpecifier *Qualifier 166 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 167 Template = Context.getQualifiedTemplateName(Qualifier, 168 hasTemplateKeyword, TD); 169 } else { 170 Template = TemplateName(TD); 171 } 172 173 if (isa<FunctionTemplateDecl>(TD)) { 174 TemplateKind = TNK_Function_template; 175 176 // We'll do this lookup again later. 177 R.suppressDiagnostics(); 178 } else { 179 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD)); 180 TemplateKind = TNK_Type_template; 181 } 182 } 183 184 TemplateResult = TemplateTy::make(Template); 185 return TemplateKind; 186} 187 188bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II, 189 SourceLocation IILoc, 190 Scope *S, 191 const CXXScopeSpec *SS, 192 TemplateTy &SuggestedTemplate, 193 TemplateNameKind &SuggestedKind) { 194 // We can't recover unless there's a dependent scope specifier preceding the 195 // template name. 196 // FIXME: Typo correction? 197 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) || 198 computeDeclContext(*SS)) 199 return false; 200 201 // The code is missing a 'template' keyword prior to the dependent template 202 // name. 203 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep(); 204 Diag(IILoc, diag::err_template_kw_missing) 205 << Qualifier << II.getName() 206 << FixItHint::CreateInsertion(IILoc, "template "); 207 SuggestedTemplate 208 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II)); 209 SuggestedKind = TNK_Dependent_template_name; 210 return true; 211} 212 213void Sema::LookupTemplateName(LookupResult &Found, 214 Scope *S, CXXScopeSpec &SS, 215 QualType ObjectType, 216 bool EnteringContext, 217 bool &MemberOfUnknownSpecialization) { 218 // Determine where to perform name lookup 219 MemberOfUnknownSpecialization = false; 220 DeclContext *LookupCtx = 0; 221 bool isDependent = false; 222 if (!ObjectType.isNull()) { 223 // This nested-name-specifier occurs in a member access expression, e.g., 224 // x->B::f, and we are looking into the type of the object. 225 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 226 LookupCtx = computeDeclContext(ObjectType); 227 isDependent = ObjectType->isDependentType(); 228 assert((isDependent || !ObjectType->isIncompleteType()) && 229 "Caller should have completed object type"); 230 } else if (SS.isSet()) { 231 // This nested-name-specifier occurs after another nested-name-specifier, 232 // so long into the context associated with the prior nested-name-specifier. 233 LookupCtx = computeDeclContext(SS, EnteringContext); 234 isDependent = isDependentScopeSpecifier(SS); 235 236 // The declaration context must be complete. 237 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx)) 238 return; 239 } 240 241 bool ObjectTypeSearchedInScope = false; 242 if (LookupCtx) { 243 // Perform "qualified" name lookup into the declaration context we 244 // computed, which is either the type of the base of a member access 245 // expression or the declaration context associated with a prior 246 // nested-name-specifier. 247 LookupQualifiedName(Found, LookupCtx); 248 249 if (!ObjectType.isNull() && Found.empty()) { 250 // C++ [basic.lookup.classref]p1: 251 // In a class member access expression (5.2.5), if the . or -> token is 252 // immediately followed by an identifier followed by a <, the 253 // identifier must be looked up to determine whether the < is the 254 // beginning of a template argument list (14.2) or a less-than operator. 255 // The identifier is first looked up in the class of the object 256 // expression. If the identifier is not found, it is then looked up in 257 // the context of the entire postfix-expression and shall name a class 258 // or function template. 259 if (S) LookupName(Found, S); 260 ObjectTypeSearchedInScope = true; 261 } 262 } else if (isDependent && (!S || ObjectType.isNull())) { 263 // We cannot look into a dependent object type or nested nme 264 // specifier. 265 MemberOfUnknownSpecialization = true; 266 return; 267 } else { 268 // Perform unqualified name lookup in the current scope. 269 LookupName(Found, S); 270 } 271 272 if (Found.empty() && !isDependent) { 273 // If we did not find any names, attempt to correct any typos. 274 DeclarationName Name = Found.getLookupName(); 275 if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx, 276 false, CTC_CXXCasts)) { 277 FilterAcceptableTemplateNames(Context, Found); 278 if (!Found.empty()) { 279 if (LookupCtx) 280 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest) 281 << Name << LookupCtx << Found.getLookupName() << SS.getRange() 282 << FixItHint::CreateReplacement(Found.getNameLoc(), 283 Found.getLookupName().getAsString()); 284 else 285 Diag(Found.getNameLoc(), diag::err_no_template_suggest) 286 << Name << Found.getLookupName() 287 << FixItHint::CreateReplacement(Found.getNameLoc(), 288 Found.getLookupName().getAsString()); 289 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>()) 290 Diag(Template->getLocation(), diag::note_previous_decl) 291 << Template->getDeclName(); 292 } 293 } else { 294 Found.clear(); 295 Found.setLookupName(Name); 296 } 297 } 298 299 FilterAcceptableTemplateNames(Context, Found); 300 if (Found.empty()) { 301 if (isDependent) 302 MemberOfUnknownSpecialization = true; 303 return; 304 } 305 306 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) { 307 // C++ [basic.lookup.classref]p1: 308 // [...] If the lookup in the class of the object expression finds a 309 // template, the name is also looked up in the context of the entire 310 // postfix-expression and [...] 311 // 312 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(), 313 LookupOrdinaryName); 314 LookupName(FoundOuter, S); 315 FilterAcceptableTemplateNames(Context, FoundOuter); 316 317 if (FoundOuter.empty()) { 318 // - if the name is not found, the name found in the class of the 319 // object expression is used, otherwise 320 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) { 321 // - if the name is found in the context of the entire 322 // postfix-expression and does not name a class template, the name 323 // found in the class of the object expression is used, otherwise 324 } else if (!Found.isSuppressingDiagnostics()) { 325 // - if the name found is a class template, it must refer to the same 326 // entity as the one found in the class of the object expression, 327 // otherwise the program is ill-formed. 328 if (!Found.isSingleResult() || 329 Found.getFoundDecl()->getCanonicalDecl() 330 != FoundOuter.getFoundDecl()->getCanonicalDecl()) { 331 Diag(Found.getNameLoc(), 332 diag::ext_nested_name_member_ref_lookup_ambiguous) 333 << Found.getLookupName() 334 << ObjectType; 335 Diag(Found.getRepresentativeDecl()->getLocation(), 336 diag::note_ambig_member_ref_object_type) 337 << ObjectType; 338 Diag(FoundOuter.getFoundDecl()->getLocation(), 339 diag::note_ambig_member_ref_scope); 340 341 // Recover by taking the template that we found in the object 342 // expression's type. 343 } 344 } 345 } 346} 347 348/// ActOnDependentIdExpression - Handle a dependent id-expression that 349/// was just parsed. This is only possible with an explicit scope 350/// specifier naming a dependent type. 351ExprResult 352Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS, 353 const DeclarationNameInfo &NameInfo, 354 bool isAddressOfOperand, 355 const TemplateArgumentListInfo *TemplateArgs) { 356 NestedNameSpecifier *Qualifier 357 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 358 359 DeclContext *DC = getFunctionLevelDeclContext(); 360 361 if (!isAddressOfOperand && 362 isa<CXXMethodDecl>(DC) && 363 cast<CXXMethodDecl>(DC)->isInstance()) { 364 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); 365 366 // Since the 'this' expression is synthesized, we don't need to 367 // perform the double-lookup check. 368 NamedDecl *FirstQualifierInScope = 0; 369 370 return Owned(CXXDependentScopeMemberExpr::Create(Context, 371 /*This*/ 0, ThisType, 372 /*IsArrow*/ true, 373 /*Op*/ SourceLocation(), 374 Qualifier, SS.getRange(), 375 FirstQualifierInScope, 376 NameInfo, 377 TemplateArgs)); 378 } 379 380 return BuildDependentDeclRefExpr(SS, NameInfo, TemplateArgs); 381} 382 383ExprResult 384Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS, 385 const DeclarationNameInfo &NameInfo, 386 const TemplateArgumentListInfo *TemplateArgs) { 387 return Owned(DependentScopeDeclRefExpr::Create(Context, 388 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 389 SS.getRange(), 390 NameInfo, 391 TemplateArgs)); 392} 393 394/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining 395/// that the template parameter 'PrevDecl' is being shadowed by a new 396/// declaration at location Loc. Returns true to indicate that this is 397/// an error, and false otherwise. 398bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { 399 assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); 400 401 // Microsoft Visual C++ permits template parameters to be shadowed. 402 if (getLangOptions().Microsoft) 403 return false; 404 405 // C++ [temp.local]p4: 406 // A template-parameter shall not be redeclared within its 407 // scope (including nested scopes). 408 Diag(Loc, diag::err_template_param_shadow) 409 << cast<NamedDecl>(PrevDecl)->getDeclName(); 410 Diag(PrevDecl->getLocation(), diag::note_template_param_here); 411 return true; 412} 413 414/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset 415/// the parameter D to reference the templated declaration and return a pointer 416/// to the template declaration. Otherwise, do nothing to D and return null. 417TemplateDecl *Sema::AdjustDeclIfTemplate(Decl *&D) { 418 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D)) { 419 D = Temp->getTemplatedDecl(); 420 return Temp; 421 } 422 return 0; 423} 424 425static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, 426 const ParsedTemplateArgument &Arg) { 427 428 switch (Arg.getKind()) { 429 case ParsedTemplateArgument::Type: { 430 TypeSourceInfo *DI; 431 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); 432 if (!DI) 433 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation()); 434 return TemplateArgumentLoc(TemplateArgument(T), DI); 435 } 436 437 case ParsedTemplateArgument::NonType: { 438 Expr *E = static_cast<Expr *>(Arg.getAsExpr()); 439 return TemplateArgumentLoc(TemplateArgument(E), E); 440 } 441 442 case ParsedTemplateArgument::Template: { 443 TemplateName Template = Arg.getAsTemplate().get(); 444 return TemplateArgumentLoc(TemplateArgument(Template), 445 Arg.getScopeSpec().getRange(), 446 Arg.getLocation()); 447 } 448 } 449 450 llvm_unreachable("Unhandled parsed template argument"); 451 return TemplateArgumentLoc(); 452} 453 454/// \brief Translates template arguments as provided by the parser 455/// into template arguments used by semantic analysis. 456void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn, 457 TemplateArgumentListInfo &TemplateArgs) { 458 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) 459 TemplateArgs.addArgument(translateTemplateArgument(*this, 460 TemplateArgsIn[I])); 461} 462 463/// ActOnTypeParameter - Called when a C++ template type parameter 464/// (e.g., "typename T") has been parsed. Typename specifies whether 465/// the keyword "typename" was used to declare the type parameter 466/// (otherwise, "class" was used), and KeyLoc is the location of the 467/// "class" or "typename" keyword. ParamName is the name of the 468/// parameter (NULL indicates an unnamed template parameter) and 469/// ParamName is the location of the parameter name (if any). 470/// If the type parameter has a default argument, it will be added 471/// later via ActOnTypeParameterDefault. 472Decl *Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, 473 SourceLocation EllipsisLoc, 474 SourceLocation KeyLoc, 475 IdentifierInfo *ParamName, 476 SourceLocation ParamNameLoc, 477 unsigned Depth, unsigned Position, 478 SourceLocation EqualLoc, 479 ParsedType DefaultArg) { 480 assert(S->isTemplateParamScope() && 481 "Template type parameter not in template parameter scope!"); 482 bool Invalid = false; 483 484 if (ParamName) { 485 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc, 486 LookupOrdinaryName, 487 ForRedeclaration); 488 if (PrevDecl && PrevDecl->isTemplateParameter()) 489 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc, 490 PrevDecl); 491 } 492 493 SourceLocation Loc = ParamNameLoc; 494 if (!ParamName) 495 Loc = KeyLoc; 496 497 TemplateTypeParmDecl *Param 498 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(), 499 Loc, Depth, Position, ParamName, Typename, 500 Ellipsis); 501 if (Invalid) 502 Param->setInvalidDecl(); 503 504 if (ParamName) { 505 // Add the template parameter into the current scope. 506 S->AddDecl(Param); 507 IdResolver.AddDecl(Param); 508 } 509 510 // Handle the default argument, if provided. 511 if (DefaultArg) { 512 TypeSourceInfo *DefaultTInfo; 513 GetTypeFromParser(DefaultArg, &DefaultTInfo); 514 515 assert(DefaultTInfo && "expected source information for type"); 516 517 // C++0x [temp.param]p9: 518 // A default template-argument may be specified for any kind of 519 // template-parameter that is not a template parameter pack. 520 if (Ellipsis) { 521 Diag(EqualLoc, diag::err_template_param_pack_default_arg); 522 return Param; 523 } 524 525 // Check the template argument itself. 526 if (CheckTemplateArgument(Param, DefaultTInfo)) { 527 Param->setInvalidDecl(); 528 return Param; 529 } 530 531 Param->setDefaultArgument(DefaultTInfo, false); 532 } 533 534 return Param; 535} 536 537/// \brief Check that the type of a non-type template parameter is 538/// well-formed. 539/// 540/// \returns the (possibly-promoted) parameter type if valid; 541/// otherwise, produces a diagnostic and returns a NULL type. 542QualType 543Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { 544 // We don't allow variably-modified types as the type of non-type template 545 // parameters. 546 if (T->isVariablyModifiedType()) { 547 Diag(Loc, diag::err_variably_modified_nontype_template_param) 548 << T; 549 return QualType(); 550 } 551 552 // C++ [temp.param]p4: 553 // 554 // A non-type template-parameter shall have one of the following 555 // (optionally cv-qualified) types: 556 // 557 // -- integral or enumeration type, 558 if (T->isIntegralOrEnumerationType() || 559 // -- pointer to object or pointer to function, 560 T->isPointerType() || 561 // -- reference to object or reference to function, 562 T->isReferenceType() || 563 // -- pointer to member. 564 T->isMemberPointerType() || 565 // If T is a dependent type, we can't do the check now, so we 566 // assume that it is well-formed. 567 T->isDependentType()) 568 return T; 569 // C++ [temp.param]p8: 570 // 571 // A non-type template-parameter of type "array of T" or 572 // "function returning T" is adjusted to be of type "pointer to 573 // T" or "pointer to function returning T", respectively. 574 else if (T->isArrayType()) 575 // FIXME: Keep the type prior to promotion? 576 return Context.getArrayDecayedType(T); 577 else if (T->isFunctionType()) 578 // FIXME: Keep the type prior to promotion? 579 return Context.getPointerType(T); 580 581 Diag(Loc, diag::err_template_nontype_parm_bad_type) 582 << T; 583 584 return QualType(); 585} 586 587Decl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, 588 unsigned Depth, 589 unsigned Position, 590 SourceLocation EqualLoc, 591 Expr *Default) { 592 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 593 QualType T = TInfo->getType(); 594 595 assert(S->isTemplateParamScope() && 596 "Non-type template parameter not in template parameter scope!"); 597 bool Invalid = false; 598 599 IdentifierInfo *ParamName = D.getIdentifier(); 600 if (ParamName) { 601 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(), 602 LookupOrdinaryName, 603 ForRedeclaration); 604 if (PrevDecl && PrevDecl->isTemplateParameter()) 605 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 606 PrevDecl); 607 } 608 609 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); 610 if (T.isNull()) { 611 T = Context.IntTy; // Recover with an 'int' type. 612 Invalid = true; 613 } 614 615 NonTypeTemplateParmDecl *Param 616 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 617 D.getIdentifierLoc(), 618 Depth, Position, ParamName, T, TInfo); 619 if (Invalid) 620 Param->setInvalidDecl(); 621 622 if (D.getIdentifier()) { 623 // Add the template parameter into the current scope. 624 S->AddDecl(Param); 625 IdResolver.AddDecl(Param); 626 } 627 628 // Check the well-formedness of the default template argument, if provided. 629 if (Default) { 630 TemplateArgument Converted; 631 if (CheckTemplateArgument(Param, Param->getType(), Default, Converted)) { 632 Param->setInvalidDecl(); 633 return Param; 634 } 635 636 Param->setDefaultArgument(Default, false); 637 } 638 639 return Param; 640} 641 642/// ActOnTemplateTemplateParameter - Called when a C++ template template 643/// parameter (e.g. T in template <template <typename> class T> class array) 644/// has been parsed. S is the current scope. 645Decl *Sema::ActOnTemplateTemplateParameter(Scope* S, 646 SourceLocation TmpLoc, 647 TemplateParamsTy *Params, 648 IdentifierInfo *Name, 649 SourceLocation NameLoc, 650 unsigned Depth, 651 unsigned Position, 652 SourceLocation EqualLoc, 653 const ParsedTemplateArgument &Default) { 654 assert(S->isTemplateParamScope() && 655 "Template template parameter not in template parameter scope!"); 656 657 // Construct the parameter object. 658 TemplateTemplateParmDecl *Param = 659 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 660 TmpLoc, Depth, Position, Name, 661 (TemplateParameterList*)Params); 662 663 // If the template template parameter has a name, then link the identifier 664 // into the scope and lookup mechanisms. 665 if (Name) { 666 S->AddDecl(Param); 667 IdResolver.AddDecl(Param); 668 } 669 670 if (!Default.isInvalid()) { 671 // Check only that we have a template template argument. We don't want to 672 // try to check well-formedness now, because our template template parameter 673 // might have dependent types in its template parameters, which we wouldn't 674 // be able to match now. 675 // 676 // If none of the template template parameter's template arguments mention 677 // other template parameters, we could actually perform more checking here. 678 // However, it isn't worth doing. 679 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); 680 if (DefaultArg.getArgument().getAsTemplate().isNull()) { 681 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) 682 << DefaultArg.getSourceRange(); 683 return Param; 684 } 685 686 Param->setDefaultArgument(DefaultArg, false); 687 } 688 689 return Param; 690} 691 692/// ActOnTemplateParameterList - Builds a TemplateParameterList that 693/// contains the template parameters in Params/NumParams. 694Sema::TemplateParamsTy * 695Sema::ActOnTemplateParameterList(unsigned Depth, 696 SourceLocation ExportLoc, 697 SourceLocation TemplateLoc, 698 SourceLocation LAngleLoc, 699 Decl **Params, unsigned NumParams, 700 SourceLocation RAngleLoc) { 701 if (ExportLoc.isValid()) 702 Diag(ExportLoc, diag::warn_template_export_unsupported); 703 704 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, 705 (NamedDecl**)Params, NumParams, 706 RAngleLoc); 707} 708 709static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) { 710 if (SS.isSet()) 711 T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 712 SS.getRange()); 713} 714 715Sema::DeclResult 716Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, 717 SourceLocation KWLoc, CXXScopeSpec &SS, 718 IdentifierInfo *Name, SourceLocation NameLoc, 719 AttributeList *Attr, 720 TemplateParameterList *TemplateParams, 721 AccessSpecifier AS) { 722 assert(TemplateParams && TemplateParams->size() > 0 && 723 "No template parameters"); 724 assert(TUK != TUK_Reference && "Can only declare or define class templates"); 725 bool Invalid = false; 726 727 // Check that we can declare a template here. 728 if (CheckTemplateDeclScope(S, TemplateParams)) 729 return true; 730 731 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 732 assert(Kind != TTK_Enum && "can't build template of enumerated type"); 733 734 // There is no such thing as an unnamed class template. 735 if (!Name) { 736 Diag(KWLoc, diag::err_template_unnamed_class); 737 return true; 738 } 739 740 // Find any previous declaration with this name. 741 DeclContext *SemanticContext; 742 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, 743 ForRedeclaration); 744 if (SS.isNotEmpty() && !SS.isInvalid()) { 745 SemanticContext = computeDeclContext(SS, true); 746 if (!SemanticContext) { 747 // FIXME: Produce a reasonable diagnostic here 748 return true; 749 } 750 751 if (RequireCompleteDeclContext(SS, SemanticContext)) 752 return true; 753 754 LookupQualifiedName(Previous, SemanticContext); 755 } else { 756 SemanticContext = CurContext; 757 LookupName(Previous, S); 758 } 759 760 if (Previous.isAmbiguous()) 761 return true; 762 763 NamedDecl *PrevDecl = 0; 764 if (Previous.begin() != Previous.end()) 765 PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 766 767 // If there is a previous declaration with the same name, check 768 // whether this is a valid redeclaration. 769 ClassTemplateDecl *PrevClassTemplate 770 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); 771 772 // We may have found the injected-class-name of a class template, 773 // class template partial specialization, or class template specialization. 774 // In these cases, grab the template that is being defined or specialized. 775 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && 776 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { 777 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); 778 PrevClassTemplate 779 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); 780 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { 781 PrevClassTemplate 782 = cast<ClassTemplateSpecializationDecl>(PrevDecl) 783 ->getSpecializedTemplate(); 784 } 785 } 786 787 if (TUK == TUK_Friend) { 788 // C++ [namespace.memdef]p3: 789 // [...] When looking for a prior declaration of a class or a function 790 // declared as a friend, and when the name of the friend class or 791 // function is neither a qualified name nor a template-id, scopes outside 792 // the innermost enclosing namespace scope are not considered. 793 if (!SS.isSet()) { 794 DeclContext *OutermostContext = CurContext; 795 while (!OutermostContext->isFileContext()) 796 OutermostContext = OutermostContext->getLookupParent(); 797 798 if (PrevDecl && 799 (OutermostContext->Equals(PrevDecl->getDeclContext()) || 800 OutermostContext->Encloses(PrevDecl->getDeclContext()))) { 801 SemanticContext = PrevDecl->getDeclContext(); 802 } else { 803 // Declarations in outer scopes don't matter. However, the outermost 804 // context we computed is the semantic context for our new 805 // declaration. 806 PrevDecl = PrevClassTemplate = 0; 807 SemanticContext = OutermostContext; 808 } 809 } 810 811 if (CurContext->isDependentContext()) { 812 // If this is a dependent context, we don't want to link the friend 813 // class template to the template in scope, because that would perform 814 // checking of the template parameter lists that can't be performed 815 // until the outer context is instantiated. 816 PrevDecl = PrevClassTemplate = 0; 817 } 818 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) 819 PrevDecl = PrevClassTemplate = 0; 820 821 if (PrevClassTemplate) { 822 // Ensure that the template parameter lists are compatible. 823 if (!TemplateParameterListsAreEqual(TemplateParams, 824 PrevClassTemplate->getTemplateParameters(), 825 /*Complain=*/true, 826 TPL_TemplateMatch)) 827 return true; 828 829 // C++ [temp.class]p4: 830 // In a redeclaration, partial specialization, explicit 831 // specialization or explicit instantiation of a class template, 832 // the class-key shall agree in kind with the original class 833 // template declaration (7.1.5.3). 834 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); 835 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) { 836 Diag(KWLoc, diag::err_use_with_wrong_tag) 837 << Name 838 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName()); 839 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); 840 Kind = PrevRecordDecl->getTagKind(); 841 } 842 843 // Check for redefinition of this class template. 844 if (TUK == TUK_Definition) { 845 if (TagDecl *Def = PrevRecordDecl->getDefinition()) { 846 Diag(NameLoc, diag::err_redefinition) << Name; 847 Diag(Def->getLocation(), diag::note_previous_definition); 848 // FIXME: Would it make sense to try to "forget" the previous 849 // definition, as part of error recovery? 850 return true; 851 } 852 } 853 } else if (PrevDecl && PrevDecl->isTemplateParameter()) { 854 // Maybe we will complain about the shadowed template parameter. 855 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 856 // Just pretend that we didn't see the previous declaration. 857 PrevDecl = 0; 858 } else if (PrevDecl) { 859 // C++ [temp]p5: 860 // A class template shall not have the same name as any other 861 // template, class, function, object, enumeration, enumerator, 862 // namespace, or type in the same scope (3.3), except as specified 863 // in (14.5.4). 864 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 865 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 866 return true; 867 } 868 869 // Check the template parameter list of this declaration, possibly 870 // merging in the template parameter list from the previous class 871 // template declaration. 872 if (CheckTemplateParameterList(TemplateParams, 873 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0, 874 TPC_ClassTemplate)) 875 Invalid = true; 876 877 if (SS.isSet()) { 878 // If the name of the template was qualified, we must be defining the 879 // template out-of-line. 880 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate && 881 !(TUK == TUK_Friend && CurContext->isDependentContext())) 882 Diag(NameLoc, diag::err_member_def_does_not_match) 883 << Name << SemanticContext << SS.getRange(); 884 } 885 886 CXXRecordDecl *NewClass = 887 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc, 888 PrevClassTemplate? 889 PrevClassTemplate->getTemplatedDecl() : 0, 890 /*DelayTypeCreation=*/true); 891 SetNestedNameSpecifier(NewClass, SS); 892 893 ClassTemplateDecl *NewTemplate 894 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, 895 DeclarationName(Name), TemplateParams, 896 NewClass, PrevClassTemplate); 897 NewClass->setDescribedClassTemplate(NewTemplate); 898 899 // Build the type for the class template declaration now. 900 QualType T = NewTemplate->getInjectedClassNameSpecialization(); 901 T = Context.getInjectedClassNameType(NewClass, T); 902 assert(T->isDependentType() && "Class template type is not dependent?"); 903 (void)T; 904 905 // If we are providing an explicit specialization of a member that is a 906 // class template, make a note of that. 907 if (PrevClassTemplate && 908 PrevClassTemplate->getInstantiatedFromMemberTemplate()) 909 PrevClassTemplate->setMemberSpecialization(); 910 911 // Set the access specifier. 912 if (!Invalid && TUK != TUK_Friend) 913 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); 914 915 // Set the lexical context of these templates 916 NewClass->setLexicalDeclContext(CurContext); 917 NewTemplate->setLexicalDeclContext(CurContext); 918 919 if (TUK == TUK_Definition) 920 NewClass->startDefinition(); 921 922 if (Attr) 923 ProcessDeclAttributeList(S, NewClass, Attr); 924 925 if (TUK != TUK_Friend) 926 PushOnScopeChains(NewTemplate, S); 927 else { 928 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { 929 NewTemplate->setAccess(PrevClassTemplate->getAccess()); 930 NewClass->setAccess(PrevClassTemplate->getAccess()); 931 } 932 933 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ 934 PrevClassTemplate != NULL); 935 936 // Friend templates are visible in fairly strange ways. 937 if (!CurContext->isDependentContext()) { 938 DeclContext *DC = SemanticContext->getLookupContext(); 939 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false); 940 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 941 PushOnScopeChains(NewTemplate, EnclosingScope, 942 /* AddToContext = */ false); 943 } 944 945 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 946 NewClass->getLocation(), 947 NewTemplate, 948 /*FIXME:*/NewClass->getLocation()); 949 Friend->setAccess(AS_public); 950 CurContext->addDecl(Friend); 951 } 952 953 if (Invalid) { 954 NewTemplate->setInvalidDecl(); 955 NewClass->setInvalidDecl(); 956 } 957 return NewTemplate; 958} 959 960/// \brief Diagnose the presence of a default template argument on a 961/// template parameter, which is ill-formed in certain contexts. 962/// 963/// \returns true if the default template argument should be dropped. 964static bool DiagnoseDefaultTemplateArgument(Sema &S, 965 Sema::TemplateParamListContext TPC, 966 SourceLocation ParamLoc, 967 SourceRange DefArgRange) { 968 switch (TPC) { 969 case Sema::TPC_ClassTemplate: 970 return false; 971 972 case Sema::TPC_FunctionTemplate: 973 // C++ [temp.param]p9: 974 // A default template-argument shall not be specified in a 975 // function template declaration or a function template 976 // definition [...] 977 // (This sentence is not in C++0x, per DR226). 978 if (!S.getLangOptions().CPlusPlus0x) 979 S.Diag(ParamLoc, 980 diag::err_template_parameter_default_in_function_template) 981 << DefArgRange; 982 return false; 983 984 case Sema::TPC_ClassTemplateMember: 985 // C++0x [temp.param]p9: 986 // A default template-argument shall not be specified in the 987 // template-parameter-lists of the definition of a member of a 988 // class template that appears outside of the member's class. 989 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member) 990 << DefArgRange; 991 return true; 992 993 case Sema::TPC_FriendFunctionTemplate: 994 // C++ [temp.param]p9: 995 // A default template-argument shall not be specified in a 996 // friend template declaration. 997 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template) 998 << DefArgRange; 999 return true; 1000 1001 // FIXME: C++0x [temp.param]p9 allows default template-arguments 1002 // for friend function templates if there is only a single 1003 // declaration (and it is a definition). Strange! 1004 } 1005 1006 return false; 1007} 1008 1009/// \brief Checks the validity of a template parameter list, possibly 1010/// considering the template parameter list from a previous 1011/// declaration. 1012/// 1013/// If an "old" template parameter list is provided, it must be 1014/// equivalent (per TemplateParameterListsAreEqual) to the "new" 1015/// template parameter list. 1016/// 1017/// \param NewParams Template parameter list for a new template 1018/// declaration. This template parameter list will be updated with any 1019/// default arguments that are carried through from the previous 1020/// template parameter list. 1021/// 1022/// \param OldParams If provided, template parameter list from a 1023/// previous declaration of the same template. Default template 1024/// arguments will be merged from the old template parameter list to 1025/// the new template parameter list. 1026/// 1027/// \param TPC Describes the context in which we are checking the given 1028/// template parameter list. 1029/// 1030/// \returns true if an error occurred, false otherwise. 1031bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, 1032 TemplateParameterList *OldParams, 1033 TemplateParamListContext TPC) { 1034 bool Invalid = false; 1035 1036 // C++ [temp.param]p10: 1037 // The set of default template-arguments available for use with a 1038 // template declaration or definition is obtained by merging the 1039 // default arguments from the definition (if in scope) and all 1040 // declarations in scope in the same way default function 1041 // arguments are (8.3.6). 1042 bool SawDefaultArgument = false; 1043 SourceLocation PreviousDefaultArgLoc; 1044 1045 bool SawParameterPack = false; 1046 SourceLocation ParameterPackLoc; 1047 1048 // Dummy initialization to avoid warnings. 1049 TemplateParameterList::iterator OldParam = NewParams->end(); 1050 if (OldParams) 1051 OldParam = OldParams->begin(); 1052 1053 for (TemplateParameterList::iterator NewParam = NewParams->begin(), 1054 NewParamEnd = NewParams->end(); 1055 NewParam != NewParamEnd; ++NewParam) { 1056 // Variables used to diagnose redundant default arguments 1057 bool RedundantDefaultArg = false; 1058 SourceLocation OldDefaultLoc; 1059 SourceLocation NewDefaultLoc; 1060 1061 // Variables used to diagnose missing default arguments 1062 bool MissingDefaultArg = false; 1063 1064 // C++0x [temp.param]p11: 1065 // If a template parameter of a class template is a template parameter pack, 1066 // it must be the last template parameter. 1067 if (SawParameterPack) { 1068 Diag(ParameterPackLoc, 1069 diag::err_template_param_pack_must_be_last_template_parameter); 1070 Invalid = true; 1071 } 1072 1073 if (TemplateTypeParmDecl *NewTypeParm 1074 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { 1075 // Check the presence of a default argument here. 1076 if (NewTypeParm->hasDefaultArgument() && 1077 DiagnoseDefaultTemplateArgument(*this, TPC, 1078 NewTypeParm->getLocation(), 1079 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc() 1080 .getSourceRange())) 1081 NewTypeParm->removeDefaultArgument(); 1082 1083 // Merge default arguments for template type parameters. 1084 TemplateTypeParmDecl *OldTypeParm 1085 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; 1086 1087 if (NewTypeParm->isParameterPack()) { 1088 assert(!NewTypeParm->hasDefaultArgument() && 1089 "Parameter packs can't have a default argument!"); 1090 SawParameterPack = true; 1091 ParameterPackLoc = NewTypeParm->getLocation(); 1092 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && 1093 NewTypeParm->hasDefaultArgument()) { 1094 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); 1095 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); 1096 SawDefaultArgument = true; 1097 RedundantDefaultArg = true; 1098 PreviousDefaultArgLoc = NewDefaultLoc; 1099 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { 1100 // Merge the default argument from the old declaration to the 1101 // new declaration. 1102 SawDefaultArgument = true; 1103 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), 1104 true); 1105 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); 1106 } else if (NewTypeParm->hasDefaultArgument()) { 1107 SawDefaultArgument = true; 1108 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); 1109 } else if (SawDefaultArgument) 1110 MissingDefaultArg = true; 1111 } else if (NonTypeTemplateParmDecl *NewNonTypeParm 1112 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { 1113 // Check the presence of a default argument here. 1114 if (NewNonTypeParm->hasDefaultArgument() && 1115 DiagnoseDefaultTemplateArgument(*this, TPC, 1116 NewNonTypeParm->getLocation(), 1117 NewNonTypeParm->getDefaultArgument()->getSourceRange())) { 1118 NewNonTypeParm->removeDefaultArgument(); 1119 } 1120 1121 // Merge default arguments for non-type template parameters 1122 NonTypeTemplateParmDecl *OldNonTypeParm 1123 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; 1124 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && 1125 NewNonTypeParm->hasDefaultArgument()) { 1126 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1127 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1128 SawDefaultArgument = true; 1129 RedundantDefaultArg = true; 1130 PreviousDefaultArgLoc = NewDefaultLoc; 1131 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { 1132 // Merge the default argument from the old declaration to the 1133 // new declaration. 1134 SawDefaultArgument = true; 1135 // FIXME: We need to create a new kind of "default argument" 1136 // expression that points to a previous template template 1137 // parameter. 1138 NewNonTypeParm->setDefaultArgument( 1139 OldNonTypeParm->getDefaultArgument(), 1140 /*Inherited=*/ true); 1141 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1142 } else if (NewNonTypeParm->hasDefaultArgument()) { 1143 SawDefaultArgument = true; 1144 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1145 } else if (SawDefaultArgument) 1146 MissingDefaultArg = true; 1147 } else { 1148 // Check the presence of a default argument here. 1149 TemplateTemplateParmDecl *NewTemplateParm 1150 = cast<TemplateTemplateParmDecl>(*NewParam); 1151 if (NewTemplateParm->hasDefaultArgument() && 1152 DiagnoseDefaultTemplateArgument(*this, TPC, 1153 NewTemplateParm->getLocation(), 1154 NewTemplateParm->getDefaultArgument().getSourceRange())) 1155 NewTemplateParm->removeDefaultArgument(); 1156 1157 // Merge default arguments for template template parameters 1158 TemplateTemplateParmDecl *OldTemplateParm 1159 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; 1160 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && 1161 NewTemplateParm->hasDefaultArgument()) { 1162 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); 1163 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); 1164 SawDefaultArgument = true; 1165 RedundantDefaultArg = true; 1166 PreviousDefaultArgLoc = NewDefaultLoc; 1167 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { 1168 // Merge the default argument from the old declaration to the 1169 // new declaration. 1170 SawDefaultArgument = true; 1171 // FIXME: We need to create a new kind of "default argument" expression 1172 // that points to a previous template template parameter. 1173 NewTemplateParm->setDefaultArgument( 1174 OldTemplateParm->getDefaultArgument(), 1175 /*Inherited=*/ true); 1176 PreviousDefaultArgLoc 1177 = OldTemplateParm->getDefaultArgument().getLocation(); 1178 } else if (NewTemplateParm->hasDefaultArgument()) { 1179 SawDefaultArgument = true; 1180 PreviousDefaultArgLoc 1181 = NewTemplateParm->getDefaultArgument().getLocation(); 1182 } else if (SawDefaultArgument) 1183 MissingDefaultArg = true; 1184 } 1185 1186 if (RedundantDefaultArg) { 1187 // C++ [temp.param]p12: 1188 // A template-parameter shall not be given default arguments 1189 // by two different declarations in the same scope. 1190 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); 1191 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); 1192 Invalid = true; 1193 } else if (MissingDefaultArg) { 1194 // C++ [temp.param]p11: 1195 // If a template-parameter has a default template-argument, 1196 // all subsequent template-parameters shall have a default 1197 // template-argument supplied. 1198 Diag((*NewParam)->getLocation(), 1199 diag::err_template_param_default_arg_missing); 1200 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); 1201 Invalid = true; 1202 } 1203 1204 // If we have an old template parameter list that we're merging 1205 // in, move on to the next parameter. 1206 if (OldParams) 1207 ++OldParam; 1208 } 1209 1210 return Invalid; 1211} 1212 1213/// \brief Match the given template parameter lists to the given scope 1214/// specifier, returning the template parameter list that applies to the 1215/// name. 1216/// 1217/// \param DeclStartLoc the start of the declaration that has a scope 1218/// specifier or a template parameter list. 1219/// 1220/// \param SS the scope specifier that will be matched to the given template 1221/// parameter lists. This scope specifier precedes a qualified name that is 1222/// being declared. 1223/// 1224/// \param ParamLists the template parameter lists, from the outermost to the 1225/// innermost template parameter lists. 1226/// 1227/// \param NumParamLists the number of template parameter lists in ParamLists. 1228/// 1229/// \param IsFriend Whether to apply the slightly different rules for 1230/// matching template parameters to scope specifiers in friend 1231/// declarations. 1232/// 1233/// \param IsExplicitSpecialization will be set true if the entity being 1234/// declared is an explicit specialization, false otherwise. 1235/// 1236/// \returns the template parameter list, if any, that corresponds to the 1237/// name that is preceded by the scope specifier @p SS. This template 1238/// parameter list may be have template parameters (if we're declaring a 1239/// template) or may have no template parameters (if we're declaring a 1240/// template specialization), or may be NULL (if we were's declaring isn't 1241/// itself a template). 1242TemplateParameterList * 1243Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, 1244 const CXXScopeSpec &SS, 1245 TemplateParameterList **ParamLists, 1246 unsigned NumParamLists, 1247 bool IsFriend, 1248 bool &IsExplicitSpecialization, 1249 bool &Invalid) { 1250 IsExplicitSpecialization = false; 1251 1252 // Find the template-ids that occur within the nested-name-specifier. These 1253 // template-ids will match up with the template parameter lists. 1254 llvm::SmallVector<const TemplateSpecializationType *, 4> 1255 TemplateIdsInSpecifier; 1256 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4> 1257 ExplicitSpecializationsInSpecifier; 1258 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 1259 NNS; NNS = NNS->getPrefix()) { 1260 const Type *T = NNS->getAsType(); 1261 if (!T) break; 1262 1263 // C++0x [temp.expl.spec]p17: 1264 // A member or a member template may be nested within many 1265 // enclosing class templates. In an explicit specialization for 1266 // such a member, the member declaration shall be preceded by a 1267 // template<> for each enclosing class template that is 1268 // explicitly specialized. 1269 // 1270 // Following the existing practice of GNU and EDG, we allow a typedef of a 1271 // template specialization type. 1272 if (const TypedefType *TT = dyn_cast<TypedefType>(T)) 1273 T = TT->LookThroughTypedefs().getTypePtr(); 1274 1275 if (const TemplateSpecializationType *SpecType 1276 = dyn_cast<TemplateSpecializationType>(T)) { 1277 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl(); 1278 if (!Template) 1279 continue; // FIXME: should this be an error? probably... 1280 1281 if (const RecordType *Record = SpecType->getAs<RecordType>()) { 1282 ClassTemplateSpecializationDecl *SpecDecl 1283 = cast<ClassTemplateSpecializationDecl>(Record->getDecl()); 1284 // If the nested name specifier refers to an explicit specialization, 1285 // we don't need a template<> header. 1286 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) { 1287 ExplicitSpecializationsInSpecifier.push_back(SpecDecl); 1288 continue; 1289 } 1290 } 1291 1292 TemplateIdsInSpecifier.push_back(SpecType); 1293 } 1294 } 1295 1296 // Reverse the list of template-ids in the scope specifier, so that we can 1297 // more easily match up the template-ids and the template parameter lists. 1298 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end()); 1299 1300 SourceLocation FirstTemplateLoc = DeclStartLoc; 1301 if (NumParamLists) 1302 FirstTemplateLoc = ParamLists[0]->getTemplateLoc(); 1303 1304 // Match the template-ids found in the specifier to the template parameter 1305 // lists. 1306 unsigned Idx = 0; 1307 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size(); 1308 Idx != NumTemplateIds; ++Idx) { 1309 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0); 1310 bool DependentTemplateId = TemplateId->isDependentType(); 1311 if (Idx >= NumParamLists) { 1312 // We have a template-id without a corresponding template parameter 1313 // list. 1314 1315 // ...which is fine if this is a friend declaration. 1316 if (IsFriend) { 1317 IsExplicitSpecialization = true; 1318 break; 1319 } 1320 1321 if (DependentTemplateId) { 1322 // FIXME: the location information here isn't great. 1323 Diag(SS.getRange().getBegin(), 1324 diag::err_template_spec_needs_template_parameters) 1325 << TemplateId 1326 << SS.getRange(); 1327 Invalid = true; 1328 } else { 1329 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header) 1330 << SS.getRange() 1331 << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> "); 1332 IsExplicitSpecialization = true; 1333 } 1334 return 0; 1335 } 1336 1337 // Check the template parameter list against its corresponding template-id. 1338 if (DependentTemplateId) { 1339 TemplateParameterList *ExpectedTemplateParams = 0; 1340 1341 // Are there cases in (e.g.) friends where this won't match? 1342 if (const InjectedClassNameType *Injected 1343 = TemplateId->getAs<InjectedClassNameType>()) { 1344 CXXRecordDecl *Record = Injected->getDecl(); 1345 if (ClassTemplatePartialSpecializationDecl *Partial = 1346 dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) 1347 ExpectedTemplateParams = Partial->getTemplateParameters(); 1348 else 1349 ExpectedTemplateParams = Record->getDescribedClassTemplate() 1350 ->getTemplateParameters(); 1351 } 1352 1353 if (ExpectedTemplateParams) 1354 TemplateParameterListsAreEqual(ParamLists[Idx], 1355 ExpectedTemplateParams, 1356 true, TPL_TemplateMatch); 1357 1358 CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember); 1359 } else if (ParamLists[Idx]->size() > 0) 1360 Diag(ParamLists[Idx]->getTemplateLoc(), 1361 diag::err_template_param_list_matches_nontemplate) 1362 << TemplateId 1363 << ParamLists[Idx]->getSourceRange(); 1364 else 1365 IsExplicitSpecialization = true; 1366 } 1367 1368 // If there were at least as many template-ids as there were template 1369 // parameter lists, then there are no template parameter lists remaining for 1370 // the declaration itself. 1371 if (Idx >= NumParamLists) 1372 return 0; 1373 1374 // If there were too many template parameter lists, complain about that now. 1375 if (Idx != NumParamLists - 1) { 1376 while (Idx < NumParamLists - 1) { 1377 bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0; 1378 Diag(ParamLists[Idx]->getTemplateLoc(), 1379 isExplicitSpecHeader? diag::warn_template_spec_extra_headers 1380 : diag::err_template_spec_extra_headers) 1381 << SourceRange(ParamLists[Idx]->getTemplateLoc(), 1382 ParamLists[Idx]->getRAngleLoc()); 1383 1384 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) { 1385 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(), 1386 diag::note_explicit_template_spec_does_not_need_header) 1387 << ExplicitSpecializationsInSpecifier.back(); 1388 ExplicitSpecializationsInSpecifier.pop_back(); 1389 } 1390 1391 // We have a template parameter list with no corresponding scope, which 1392 // means that the resulting template declaration can't be instantiated 1393 // properly (we'll end up with dependent nodes when we shouldn't). 1394 if (!isExplicitSpecHeader) 1395 Invalid = true; 1396 1397 ++Idx; 1398 } 1399 } 1400 1401 // Return the last template parameter list, which corresponds to the 1402 // entity being declared. 1403 return ParamLists[NumParamLists - 1]; 1404} 1405 1406QualType Sema::CheckTemplateIdType(TemplateName Name, 1407 SourceLocation TemplateLoc, 1408 const TemplateArgumentListInfo &TemplateArgs) { 1409 TemplateDecl *Template = Name.getAsTemplateDecl(); 1410 if (!Template) { 1411 // The template name does not resolve to a template, so we just 1412 // build a dependent template-id type. 1413 return Context.getTemplateSpecializationType(Name, TemplateArgs); 1414 } 1415 1416 // Check that the template argument list is well-formed for this 1417 // template. 1418 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(), 1419 TemplateArgs.size()); 1420 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs, 1421 false, Converted)) 1422 return QualType(); 1423 1424 assert((Converted.structuredSize() == 1425 Template->getTemplateParameters()->size()) && 1426 "Converted template argument list is too short!"); 1427 1428 QualType CanonType; 1429 1430 if (Name.isDependent() || 1431 TemplateSpecializationType::anyDependentTemplateArguments( 1432 TemplateArgs)) { 1433 // This class template specialization is a dependent 1434 // type. Therefore, its canonical type is another class template 1435 // specialization type that contains all of the converted 1436 // arguments in canonical form. This ensures that, e.g., A<T> and 1437 // A<T, T> have identical types when A is declared as: 1438 // 1439 // template<typename T, typename U = T> struct A; 1440 TemplateName CanonName = Context.getCanonicalTemplateName(Name); 1441 CanonType = Context.getTemplateSpecializationType(CanonName, 1442 Converted.getFlatArguments(), 1443 Converted.flatSize()); 1444 1445 // FIXME: CanonType is not actually the canonical type, and unfortunately 1446 // it is a TemplateSpecializationType that we will never use again. 1447 // In the future, we need to teach getTemplateSpecializationType to only 1448 // build the canonical type and return that to us. 1449 CanonType = Context.getCanonicalType(CanonType); 1450 1451 // This might work out to be a current instantiation, in which 1452 // case the canonical type needs to be the InjectedClassNameType. 1453 // 1454 // TODO: in theory this could be a simple hashtable lookup; most 1455 // changes to CurContext don't change the set of current 1456 // instantiations. 1457 if (isa<ClassTemplateDecl>(Template)) { 1458 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) { 1459 // If we get out to a namespace, we're done. 1460 if (Ctx->isFileContext()) break; 1461 1462 // If this isn't a record, keep looking. 1463 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx); 1464 if (!Record) continue; 1465 1466 // Look for one of the two cases with InjectedClassNameTypes 1467 // and check whether it's the same template. 1468 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) && 1469 !Record->getDescribedClassTemplate()) 1470 continue; 1471 1472 // Fetch the injected class name type and check whether its 1473 // injected type is equal to the type we just built. 1474 QualType ICNT = Context.getTypeDeclType(Record); 1475 QualType Injected = cast<InjectedClassNameType>(ICNT) 1476 ->getInjectedSpecializationType(); 1477 1478 if (CanonType != Injected->getCanonicalTypeInternal()) 1479 continue; 1480 1481 // If so, the canonical type of this TST is the injected 1482 // class name type of the record we just found. 1483 assert(ICNT.isCanonical()); 1484 CanonType = ICNT; 1485 break; 1486 } 1487 } 1488 } else if (ClassTemplateDecl *ClassTemplate 1489 = dyn_cast<ClassTemplateDecl>(Template)) { 1490 // Find the class template specialization declaration that 1491 // corresponds to these arguments. 1492 void *InsertPos = 0; 1493 ClassTemplateSpecializationDecl *Decl 1494 = ClassTemplate->findSpecialization(Converted.getFlatArguments(), 1495 Converted.flatSize(), InsertPos); 1496 if (!Decl) { 1497 // This is the first time we have referenced this class template 1498 // specialization. Create the canonical declaration and add it to 1499 // the set of specializations. 1500 Decl = ClassTemplateSpecializationDecl::Create(Context, 1501 ClassTemplate->getTemplatedDecl()->getTagKind(), 1502 ClassTemplate->getDeclContext(), 1503 ClassTemplate->getLocation(), 1504 ClassTemplate, 1505 Converted, 0); 1506 ClassTemplate->AddSpecialization(Decl, InsertPos); 1507 Decl->setLexicalDeclContext(CurContext); 1508 } 1509 1510 CanonType = Context.getTypeDeclType(Decl); 1511 assert(isa<RecordType>(CanonType) && 1512 "type of non-dependent specialization is not a RecordType"); 1513 } 1514 1515 // Build the fully-sugared type for this class template 1516 // specialization, which refers back to the class template 1517 // specialization we created or found. 1518 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); 1519} 1520 1521Action::TypeResult 1522Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc, 1523 SourceLocation LAngleLoc, 1524 ASTTemplateArgsPtr TemplateArgsIn, 1525 SourceLocation RAngleLoc) { 1526 TemplateName Template = TemplateD.getAsVal<TemplateName>(); 1527 1528 // Translate the parser's template argument list in our AST format. 1529 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 1530 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 1531 1532 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); 1533 TemplateArgsIn.release(); 1534 1535 if (Result.isNull()) 1536 return true; 1537 1538 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result); 1539 TemplateSpecializationTypeLoc TL 1540 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc()); 1541 TL.setTemplateNameLoc(TemplateLoc); 1542 TL.setLAngleLoc(LAngleLoc); 1543 TL.setRAngleLoc(RAngleLoc); 1544 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) 1545 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); 1546 1547 return CreateParsedType(Result, DI); 1548} 1549 1550Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult, 1551 TagUseKind TUK, 1552 DeclSpec::TST TagSpec, 1553 SourceLocation TagLoc) { 1554 if (TypeResult.isInvalid()) 1555 return Sema::TypeResult(); 1556 1557 // FIXME: preserve source info, ideally without copying the DI. 1558 TypeSourceInfo *DI; 1559 QualType Type = GetTypeFromParser(TypeResult.get(), &DI); 1560 1561 // Verify the tag specifier. 1562 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 1563 1564 if (const RecordType *RT = Type->getAs<RecordType>()) { 1565 RecordDecl *D = RT->getDecl(); 1566 1567 IdentifierInfo *Id = D->getIdentifier(); 1568 assert(Id && "templated class must have an identifier"); 1569 1570 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) { 1571 Diag(TagLoc, diag::err_use_with_wrong_tag) 1572 << Type 1573 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName()); 1574 Diag(D->getLocation(), diag::note_previous_use); 1575 } 1576 } 1577 1578 ElaboratedTypeKeyword Keyword 1579 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind); 1580 QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type); 1581 1582 return ParsedType::make(ElabType); 1583} 1584 1585ExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS, 1586 LookupResult &R, 1587 bool RequiresADL, 1588 const TemplateArgumentListInfo &TemplateArgs) { 1589 // FIXME: Can we do any checking at this point? I guess we could check the 1590 // template arguments that we have against the template name, if the template 1591 // name refers to a single template. That's not a terribly common case, 1592 // though. 1593 1594 // These should be filtered out by our callers. 1595 assert(!R.empty() && "empty lookup results when building templateid"); 1596 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid"); 1597 1598 NestedNameSpecifier *Qualifier = 0; 1599 SourceRange QualifierRange; 1600 if (SS.isSet()) { 1601 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 1602 QualifierRange = SS.getRange(); 1603 } 1604 1605 // We don't want lookup warnings at this point. 1606 R.suppressDiagnostics(); 1607 1608 bool Dependent 1609 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 1610 &TemplateArgs); 1611 UnresolvedLookupExpr *ULE 1612 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1613 Qualifier, QualifierRange, 1614 R.getLookupNameInfo(), 1615 RequiresADL, TemplateArgs, 1616 R.begin(), R.end()); 1617 1618 return Owned(ULE); 1619} 1620 1621// We actually only call this from template instantiation. 1622ExprResult 1623Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS, 1624 const DeclarationNameInfo &NameInfo, 1625 const TemplateArgumentListInfo &TemplateArgs) { 1626 DeclContext *DC; 1627 if (!(DC = computeDeclContext(SS, false)) || 1628 DC->isDependentContext() || 1629 RequireCompleteDeclContext(SS, DC)) 1630 return BuildDependentDeclRefExpr(SS, NameInfo, &TemplateArgs); 1631 1632 bool MemberOfUnknownSpecialization; 1633 LookupResult R(*this, NameInfo, LookupOrdinaryName); 1634 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false, 1635 MemberOfUnknownSpecialization); 1636 1637 if (R.isAmbiguous()) 1638 return ExprError(); 1639 1640 if (R.empty()) { 1641 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_non_template) 1642 << NameInfo.getName() << SS.getRange(); 1643 return ExprError(); 1644 } 1645 1646 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) { 1647 Diag(NameInfo.getLoc(), diag::err_template_kw_refers_to_class_template) 1648 << (NestedNameSpecifier*) SS.getScopeRep() 1649 << NameInfo.getName() << SS.getRange(); 1650 Diag(Temp->getLocation(), diag::note_referenced_class_template); 1651 return ExprError(); 1652 } 1653 1654 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs); 1655} 1656 1657/// \brief Form a dependent template name. 1658/// 1659/// This action forms a dependent template name given the template 1660/// name and its (presumably dependent) scope specifier. For 1661/// example, given "MetaFun::template apply", the scope specifier \p 1662/// SS will be "MetaFun::", \p TemplateKWLoc contains the location 1663/// of the "template" keyword, and "apply" is the \p Name. 1664TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S, 1665 SourceLocation TemplateKWLoc, 1666 CXXScopeSpec &SS, 1667 UnqualifiedId &Name, 1668 ParsedType ObjectType, 1669 bool EnteringContext, 1670 TemplateTy &Result) { 1671 if (TemplateKWLoc.isValid() && S && !S->getTemplateParamParent() && 1672 !getLangOptions().CPlusPlus0x) 1673 Diag(TemplateKWLoc, diag::ext_template_outside_of_template) 1674 << FixItHint::CreateRemoval(TemplateKWLoc); 1675 1676 DeclContext *LookupCtx = 0; 1677 if (SS.isSet()) 1678 LookupCtx = computeDeclContext(SS, EnteringContext); 1679 if (!LookupCtx && ObjectType) 1680 LookupCtx = computeDeclContext(ObjectType.get()); 1681 if (LookupCtx) { 1682 // C++0x [temp.names]p5: 1683 // If a name prefixed by the keyword template is not the name of 1684 // a template, the program is ill-formed. [Note: the keyword 1685 // template may not be applied to non-template members of class 1686 // templates. -end note ] [ Note: as is the case with the 1687 // typename prefix, the template prefix is allowed in cases 1688 // where it is not strictly necessary; i.e., when the 1689 // nested-name-specifier or the expression on the left of the -> 1690 // or . is not dependent on a template-parameter, or the use 1691 // does not appear in the scope of a template. -end note] 1692 // 1693 // Note: C++03 was more strict here, because it banned the use of 1694 // the "template" keyword prior to a template-name that was not a 1695 // dependent name. C++ DR468 relaxed this requirement (the 1696 // "template" keyword is now permitted). We follow the C++0x 1697 // rules, even in C++03 mode with a warning, retroactively applying the DR. 1698 bool MemberOfUnknownSpecialization; 1699 TemplateNameKind TNK = isTemplateName(0, SS, TemplateKWLoc.isValid(), Name, 1700 ObjectType, EnteringContext, Result, 1701 MemberOfUnknownSpecialization); 1702 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() && 1703 isa<CXXRecordDecl>(LookupCtx) && 1704 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) { 1705 // This is a dependent template. Handle it below. 1706 } else if (TNK == TNK_Non_template) { 1707 Diag(Name.getSourceRange().getBegin(), 1708 diag::err_template_kw_refers_to_non_template) 1709 << GetNameFromUnqualifiedId(Name).getName() 1710 << Name.getSourceRange() 1711 << TemplateKWLoc; 1712 return TNK_Non_template; 1713 } else { 1714 // We found something; return it. 1715 return TNK; 1716 } 1717 } 1718 1719 NestedNameSpecifier *Qualifier 1720 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1721 1722 switch (Name.getKind()) { 1723 case UnqualifiedId::IK_Identifier: 1724 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1725 Name.Identifier)); 1726 return TNK_Dependent_template_name; 1727 1728 case UnqualifiedId::IK_OperatorFunctionId: 1729 Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1730 Name.OperatorFunctionId.Operator)); 1731 return TNK_Dependent_template_name; 1732 1733 case UnqualifiedId::IK_LiteralOperatorId: 1734 assert(false && "We don't support these; Parse shouldn't have allowed propagation"); 1735 1736 default: 1737 break; 1738 } 1739 1740 Diag(Name.getSourceRange().getBegin(), 1741 diag::err_template_kw_refers_to_non_template) 1742 << GetNameFromUnqualifiedId(Name).getName() 1743 << Name.getSourceRange() 1744 << TemplateKWLoc; 1745 return TNK_Non_template; 1746} 1747 1748bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, 1749 const TemplateArgumentLoc &AL, 1750 TemplateArgumentListBuilder &Converted) { 1751 const TemplateArgument &Arg = AL.getArgument(); 1752 1753 // Check template type parameter. 1754 switch(Arg.getKind()) { 1755 case TemplateArgument::Type: 1756 // C++ [temp.arg.type]p1: 1757 // A template-argument for a template-parameter which is a 1758 // type shall be a type-id. 1759 break; 1760 case TemplateArgument::Template: { 1761 // We have a template type parameter but the template argument 1762 // is a template without any arguments. 1763 SourceRange SR = AL.getSourceRange(); 1764 TemplateName Name = Arg.getAsTemplate(); 1765 Diag(SR.getBegin(), diag::err_template_missing_args) 1766 << Name << SR; 1767 if (TemplateDecl *Decl = Name.getAsTemplateDecl()) 1768 Diag(Decl->getLocation(), diag::note_template_decl_here); 1769 1770 return true; 1771 } 1772 default: { 1773 // We have a template type parameter but the template argument 1774 // is not a type. 1775 SourceRange SR = AL.getSourceRange(); 1776 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; 1777 Diag(Param->getLocation(), diag::note_template_param_here); 1778 1779 return true; 1780 } 1781 } 1782 1783 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo())) 1784 return true; 1785 1786 // Add the converted template type argument. 1787 Converted.Append( 1788 TemplateArgument(Context.getCanonicalType(Arg.getAsType()))); 1789 return false; 1790} 1791 1792/// \brief Substitute template arguments into the default template argument for 1793/// the given template type parameter. 1794/// 1795/// \param SemaRef the semantic analysis object for which we are performing 1796/// the substitution. 1797/// 1798/// \param Template the template that we are synthesizing template arguments 1799/// for. 1800/// 1801/// \param TemplateLoc the location of the template name that started the 1802/// template-id we are checking. 1803/// 1804/// \param RAngleLoc the location of the right angle bracket ('>') that 1805/// terminates the template-id. 1806/// 1807/// \param Param the template template parameter whose default we are 1808/// substituting into. 1809/// 1810/// \param Converted the list of template arguments provided for template 1811/// parameters that precede \p Param in the template parameter list. 1812/// 1813/// \returns the substituted template argument, or NULL if an error occurred. 1814static TypeSourceInfo * 1815SubstDefaultTemplateArgument(Sema &SemaRef, 1816 TemplateDecl *Template, 1817 SourceLocation TemplateLoc, 1818 SourceLocation RAngleLoc, 1819 TemplateTypeParmDecl *Param, 1820 TemplateArgumentListBuilder &Converted) { 1821 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo(); 1822 1823 // If the argument type is dependent, instantiate it now based 1824 // on the previously-computed template arguments. 1825 if (ArgType->getType()->isDependentType()) { 1826 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1827 /*TakeArgs=*/false); 1828 1829 MultiLevelTemplateArgumentList AllTemplateArgs 1830 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1831 1832 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1833 Template, Converted.getFlatArguments(), 1834 Converted.flatSize(), 1835 SourceRange(TemplateLoc, RAngleLoc)); 1836 1837 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, 1838 Param->getDefaultArgumentLoc(), 1839 Param->getDeclName()); 1840 } 1841 1842 return ArgType; 1843} 1844 1845/// \brief Substitute template arguments into the default template argument for 1846/// the given non-type template parameter. 1847/// 1848/// \param SemaRef the semantic analysis object for which we are performing 1849/// the substitution. 1850/// 1851/// \param Template the template that we are synthesizing template arguments 1852/// for. 1853/// 1854/// \param TemplateLoc the location of the template name that started the 1855/// template-id we are checking. 1856/// 1857/// \param RAngleLoc the location of the right angle bracket ('>') that 1858/// terminates the template-id. 1859/// 1860/// \param Param the non-type template parameter whose default we are 1861/// substituting into. 1862/// 1863/// \param Converted the list of template arguments provided for template 1864/// parameters that precede \p Param in the template parameter list. 1865/// 1866/// \returns the substituted template argument, or NULL if an error occurred. 1867static ExprResult 1868SubstDefaultTemplateArgument(Sema &SemaRef, 1869 TemplateDecl *Template, 1870 SourceLocation TemplateLoc, 1871 SourceLocation RAngleLoc, 1872 NonTypeTemplateParmDecl *Param, 1873 TemplateArgumentListBuilder &Converted) { 1874 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1875 /*TakeArgs=*/false); 1876 1877 MultiLevelTemplateArgumentList AllTemplateArgs 1878 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1879 1880 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1881 Template, Converted.getFlatArguments(), 1882 Converted.flatSize(), 1883 SourceRange(TemplateLoc, RAngleLoc)); 1884 1885 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); 1886} 1887 1888/// \brief Substitute template arguments into the default template argument for 1889/// the given template template parameter. 1890/// 1891/// \param SemaRef the semantic analysis object for which we are performing 1892/// the substitution. 1893/// 1894/// \param Template the template that we are synthesizing template arguments 1895/// for. 1896/// 1897/// \param TemplateLoc the location of the template name that started the 1898/// template-id we are checking. 1899/// 1900/// \param RAngleLoc the location of the right angle bracket ('>') that 1901/// terminates the template-id. 1902/// 1903/// \param Param the template template parameter whose default we are 1904/// substituting into. 1905/// 1906/// \param Converted the list of template arguments provided for template 1907/// parameters that precede \p Param in the template parameter list. 1908/// 1909/// \returns the substituted template argument, or NULL if an error occurred. 1910static TemplateName 1911SubstDefaultTemplateArgument(Sema &SemaRef, 1912 TemplateDecl *Template, 1913 SourceLocation TemplateLoc, 1914 SourceLocation RAngleLoc, 1915 TemplateTemplateParmDecl *Param, 1916 TemplateArgumentListBuilder &Converted) { 1917 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1918 /*TakeArgs=*/false); 1919 1920 MultiLevelTemplateArgumentList AllTemplateArgs 1921 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1922 1923 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1924 Template, Converted.getFlatArguments(), 1925 Converted.flatSize(), 1926 SourceRange(TemplateLoc, RAngleLoc)); 1927 1928 return SemaRef.SubstTemplateName( 1929 Param->getDefaultArgument().getArgument().getAsTemplate(), 1930 Param->getDefaultArgument().getTemplateNameLoc(), 1931 AllTemplateArgs); 1932} 1933 1934/// \brief If the given template parameter has a default template 1935/// argument, substitute into that default template argument and 1936/// return the corresponding template argument. 1937TemplateArgumentLoc 1938Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template, 1939 SourceLocation TemplateLoc, 1940 SourceLocation RAngleLoc, 1941 Decl *Param, 1942 TemplateArgumentListBuilder &Converted) { 1943 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) { 1944 if (!TypeParm->hasDefaultArgument()) 1945 return TemplateArgumentLoc(); 1946 1947 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template, 1948 TemplateLoc, 1949 RAngleLoc, 1950 TypeParm, 1951 Converted); 1952 if (DI) 1953 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI); 1954 1955 return TemplateArgumentLoc(); 1956 } 1957 1958 if (NonTypeTemplateParmDecl *NonTypeParm 1959 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1960 if (!NonTypeParm->hasDefaultArgument()) 1961 return TemplateArgumentLoc(); 1962 1963 ExprResult Arg = SubstDefaultTemplateArgument(*this, Template, 1964 TemplateLoc, 1965 RAngleLoc, 1966 NonTypeParm, 1967 Converted); 1968 if (Arg.isInvalid()) 1969 return TemplateArgumentLoc(); 1970 1971 Expr *ArgE = Arg.takeAs<Expr>(); 1972 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE); 1973 } 1974 1975 TemplateTemplateParmDecl *TempTempParm 1976 = cast<TemplateTemplateParmDecl>(Param); 1977 if (!TempTempParm->hasDefaultArgument()) 1978 return TemplateArgumentLoc(); 1979 1980 TemplateName TName = SubstDefaultTemplateArgument(*this, Template, 1981 TemplateLoc, 1982 RAngleLoc, 1983 TempTempParm, 1984 Converted); 1985 if (TName.isNull()) 1986 return TemplateArgumentLoc(); 1987 1988 return TemplateArgumentLoc(TemplateArgument(TName), 1989 TempTempParm->getDefaultArgument().getTemplateQualifierRange(), 1990 TempTempParm->getDefaultArgument().getTemplateNameLoc()); 1991} 1992 1993/// \brief Check that the given template argument corresponds to the given 1994/// template parameter. 1995bool Sema::CheckTemplateArgument(NamedDecl *Param, 1996 const TemplateArgumentLoc &Arg, 1997 TemplateDecl *Template, 1998 SourceLocation TemplateLoc, 1999 SourceLocation RAngleLoc, 2000 TemplateArgumentListBuilder &Converted, 2001 CheckTemplateArgumentKind CTAK) { 2002 // Check template type parameters. 2003 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) 2004 return CheckTemplateTypeArgument(TTP, Arg, Converted); 2005 2006 // Check non-type template parameters. 2007 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { 2008 // Do substitution on the type of the non-type template parameter 2009 // with the template arguments we've seen thus far. 2010 QualType NTTPType = NTTP->getType(); 2011 if (NTTPType->isDependentType()) { 2012 // Do substitution on the type of the non-type template parameter. 2013 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2014 NTTP, Converted.getFlatArguments(), 2015 Converted.flatSize(), 2016 SourceRange(TemplateLoc, RAngleLoc)); 2017 2018 TemplateArgumentList TemplateArgs(Context, Converted, 2019 /*TakeArgs=*/false); 2020 NTTPType = SubstType(NTTPType, 2021 MultiLevelTemplateArgumentList(TemplateArgs), 2022 NTTP->getLocation(), 2023 NTTP->getDeclName()); 2024 // If that worked, check the non-type template parameter type 2025 // for validity. 2026 if (!NTTPType.isNull()) 2027 NTTPType = CheckNonTypeTemplateParameterType(NTTPType, 2028 NTTP->getLocation()); 2029 if (NTTPType.isNull()) 2030 return true; 2031 } 2032 2033 switch (Arg.getArgument().getKind()) { 2034 case TemplateArgument::Null: 2035 assert(false && "Should never see a NULL template argument here"); 2036 return true; 2037 2038 case TemplateArgument::Expression: { 2039 Expr *E = Arg.getArgument().getAsExpr(); 2040 TemplateArgument Result; 2041 if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK)) 2042 return true; 2043 2044 Converted.Append(Result); 2045 break; 2046 } 2047 2048 case TemplateArgument::Declaration: 2049 case TemplateArgument::Integral: 2050 // We've already checked this template argument, so just copy 2051 // it to the list of converted arguments. 2052 Converted.Append(Arg.getArgument()); 2053 break; 2054 2055 case TemplateArgument::Template: 2056 // We were given a template template argument. It may not be ill-formed; 2057 // see below. 2058 if (DependentTemplateName *DTN 2059 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) { 2060 // We have a template argument such as \c T::template X, which we 2061 // parsed as a template template argument. However, since we now 2062 // know that we need a non-type template argument, convert this 2063 // template name into an expression. 2064 2065 DeclarationNameInfo NameInfo(DTN->getIdentifier(), 2066 Arg.getTemplateNameLoc()); 2067 2068 Expr *E = DependentScopeDeclRefExpr::Create(Context, 2069 DTN->getQualifier(), 2070 Arg.getTemplateQualifierRange(), 2071 NameInfo); 2072 2073 TemplateArgument Result; 2074 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 2075 return true; 2076 2077 Converted.Append(Result); 2078 break; 2079 } 2080 2081 // We have a template argument that actually does refer to a class 2082 // template, template alias, or template template parameter, and 2083 // therefore cannot be a non-type template argument. 2084 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) 2085 << Arg.getSourceRange(); 2086 2087 Diag(Param->getLocation(), diag::note_template_param_here); 2088 return true; 2089 2090 case TemplateArgument::Type: { 2091 // We have a non-type template parameter but the template 2092 // argument is a type. 2093 2094 // C++ [temp.arg]p2: 2095 // In a template-argument, an ambiguity between a type-id and 2096 // an expression is resolved to a type-id, regardless of the 2097 // form of the corresponding template-parameter. 2098 // 2099 // We warn specifically about this case, since it can be rather 2100 // confusing for users. 2101 QualType T = Arg.getArgument().getAsType(); 2102 SourceRange SR = Arg.getSourceRange(); 2103 if (T->isFunctionType()) 2104 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; 2105 else 2106 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; 2107 Diag(Param->getLocation(), diag::note_template_param_here); 2108 return true; 2109 } 2110 2111 case TemplateArgument::Pack: 2112 llvm_unreachable("Caller must expand template argument packs"); 2113 break; 2114 } 2115 2116 return false; 2117 } 2118 2119 2120 // Check template template parameters. 2121 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); 2122 2123 // Substitute into the template parameter list of the template 2124 // template parameter, since previously-supplied template arguments 2125 // may appear within the template template parameter. 2126 { 2127 // Set up a template instantiation context. 2128 LocalInstantiationScope Scope(*this); 2129 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2130 TempParm, Converted.getFlatArguments(), 2131 Converted.flatSize(), 2132 SourceRange(TemplateLoc, RAngleLoc)); 2133 2134 TemplateArgumentList TemplateArgs(Context, Converted, 2135 /*TakeArgs=*/false); 2136 TempParm = cast_or_null<TemplateTemplateParmDecl>( 2137 SubstDecl(TempParm, CurContext, 2138 MultiLevelTemplateArgumentList(TemplateArgs))); 2139 if (!TempParm) 2140 return true; 2141 2142 // FIXME: TempParam is leaked. 2143 } 2144 2145 switch (Arg.getArgument().getKind()) { 2146 case TemplateArgument::Null: 2147 assert(false && "Should never see a NULL template argument here"); 2148 return true; 2149 2150 case TemplateArgument::Template: 2151 if (CheckTemplateArgument(TempParm, Arg)) 2152 return true; 2153 2154 Converted.Append(Arg.getArgument()); 2155 break; 2156 2157 case TemplateArgument::Expression: 2158 case TemplateArgument::Type: 2159 // We have a template template parameter but the template 2160 // argument does not refer to a template. 2161 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template); 2162 return true; 2163 2164 case TemplateArgument::Declaration: 2165 llvm_unreachable( 2166 "Declaration argument with template template parameter"); 2167 break; 2168 case TemplateArgument::Integral: 2169 llvm_unreachable( 2170 "Integral argument with template template parameter"); 2171 break; 2172 2173 case TemplateArgument::Pack: 2174 llvm_unreachable("Caller must expand template argument packs"); 2175 break; 2176 } 2177 2178 return false; 2179} 2180 2181/// \brief Check that the given template argument list is well-formed 2182/// for specializing the given template. 2183bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, 2184 SourceLocation TemplateLoc, 2185 const TemplateArgumentListInfo &TemplateArgs, 2186 bool PartialTemplateArgs, 2187 TemplateArgumentListBuilder &Converted) { 2188 TemplateParameterList *Params = Template->getTemplateParameters(); 2189 unsigned NumParams = Params->size(); 2190 unsigned NumArgs = TemplateArgs.size(); 2191 bool Invalid = false; 2192 2193 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc(); 2194 2195 bool HasParameterPack = 2196 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); 2197 2198 if ((NumArgs > NumParams && !HasParameterPack) || 2199 (NumArgs < Params->getMinRequiredArguments() && 2200 !PartialTemplateArgs)) { 2201 // FIXME: point at either the first arg beyond what we can handle, 2202 // or the '>', depending on whether we have too many or too few 2203 // arguments. 2204 SourceRange Range; 2205 if (NumArgs > NumParams) 2206 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc); 2207 Diag(TemplateLoc, diag::err_template_arg_list_different_arity) 2208 << (NumArgs > NumParams) 2209 << (isa<ClassTemplateDecl>(Template)? 0 : 2210 isa<FunctionTemplateDecl>(Template)? 1 : 2211 isa<TemplateTemplateParmDecl>(Template)? 2 : 3) 2212 << Template << Range; 2213 Diag(Template->getLocation(), diag::note_template_decl_here) 2214 << Params->getSourceRange(); 2215 Invalid = true; 2216 } 2217 2218 // C++ [temp.arg]p1: 2219 // [...] The type and form of each template-argument specified in 2220 // a template-id shall match the type and form specified for the 2221 // corresponding parameter declared by the template in its 2222 // template-parameter-list. 2223 unsigned ArgIdx = 0; 2224 for (TemplateParameterList::iterator Param = Params->begin(), 2225 ParamEnd = Params->end(); 2226 Param != ParamEnd; ++Param, ++ArgIdx) { 2227 if (ArgIdx > NumArgs && PartialTemplateArgs) 2228 break; 2229 2230 // If we have a template parameter pack, check every remaining template 2231 // argument against that template parameter pack. 2232 if ((*Param)->isTemplateParameterPack()) { 2233 Converted.BeginPack(); 2234 for (; ArgIdx < NumArgs; ++ArgIdx) { 2235 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2236 TemplateLoc, RAngleLoc, Converted)) { 2237 Invalid = true; 2238 break; 2239 } 2240 } 2241 Converted.EndPack(); 2242 continue; 2243 } 2244 2245 if (ArgIdx < NumArgs) { 2246 // Check the template argument we were given. 2247 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2248 TemplateLoc, RAngleLoc, Converted)) 2249 return true; 2250 2251 continue; 2252 } 2253 2254 // We have a default template argument that we will use. 2255 TemplateArgumentLoc Arg; 2256 2257 // Retrieve the default template argument from the template 2258 // parameter. For each kind of template parameter, we substitute the 2259 // template arguments provided thus far and any "outer" template arguments 2260 // (when the template parameter was part of a nested template) into 2261 // the default argument. 2262 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { 2263 if (!TTP->hasDefaultArgument()) { 2264 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2265 break; 2266 } 2267 2268 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this, 2269 Template, 2270 TemplateLoc, 2271 RAngleLoc, 2272 TTP, 2273 Converted); 2274 if (!ArgType) 2275 return true; 2276 2277 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), 2278 ArgType); 2279 } else if (NonTypeTemplateParmDecl *NTTP 2280 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { 2281 if (!NTTP->hasDefaultArgument()) { 2282 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2283 break; 2284 } 2285 2286 ExprResult E = SubstDefaultTemplateArgument(*this, Template, 2287 TemplateLoc, 2288 RAngleLoc, 2289 NTTP, 2290 Converted); 2291 if (E.isInvalid()) 2292 return true; 2293 2294 Expr *Ex = E.takeAs<Expr>(); 2295 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); 2296 } else { 2297 TemplateTemplateParmDecl *TempParm 2298 = cast<TemplateTemplateParmDecl>(*Param); 2299 2300 if (!TempParm->hasDefaultArgument()) { 2301 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2302 break; 2303 } 2304 2305 TemplateName Name = SubstDefaultTemplateArgument(*this, Template, 2306 TemplateLoc, 2307 RAngleLoc, 2308 TempParm, 2309 Converted); 2310 if (Name.isNull()) 2311 return true; 2312 2313 Arg = TemplateArgumentLoc(TemplateArgument(Name), 2314 TempParm->getDefaultArgument().getTemplateQualifierRange(), 2315 TempParm->getDefaultArgument().getTemplateNameLoc()); 2316 } 2317 2318 // Introduce an instantiation record that describes where we are using 2319 // the default template argument. 2320 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, 2321 Converted.getFlatArguments(), 2322 Converted.flatSize(), 2323 SourceRange(TemplateLoc, RAngleLoc)); 2324 2325 // Check the default template argument. 2326 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, 2327 RAngleLoc, Converted)) 2328 return true; 2329 } 2330 2331 return Invalid; 2332} 2333 2334/// \brief Check a template argument against its corresponding 2335/// template type parameter. 2336/// 2337/// This routine implements the semantics of C++ [temp.arg.type]. It 2338/// returns true if an error occurred, and false otherwise. 2339bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, 2340 TypeSourceInfo *ArgInfo) { 2341 assert(ArgInfo && "invalid TypeSourceInfo"); 2342 QualType Arg = ArgInfo->getType(); 2343 2344 // C++ [temp.arg.type]p2: 2345 // A local type, a type with no linkage, an unnamed type or a type 2346 // compounded from any of these types shall not be used as a 2347 // template-argument for a template type-parameter. 2348 // 2349 // FIXME: Perform the unnamed type check. 2350 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); 2351 const TagType *Tag = 0; 2352 if (const EnumType *EnumT = Arg->getAs<EnumType>()) 2353 Tag = EnumT; 2354 else if (const RecordType *RecordT = Arg->getAs<RecordType>()) 2355 Tag = RecordT; 2356 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) { 2357 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); 2358 return Diag(SR.getBegin(), diag::err_template_arg_local_type) 2359 << QualType(Tag, 0) << SR; 2360 } else if (Tag && !Tag->getDecl()->getDeclName() && 2361 !Tag->getDecl()->getTypedefForAnonDecl()) { 2362 Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR; 2363 Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here); 2364 return true; 2365 } else if (Arg->isVariablyModifiedType()) { 2366 Diag(SR.getBegin(), diag::err_variably_modified_template_arg) 2367 << Arg; 2368 return true; 2369 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) { 2370 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR; 2371 } 2372 2373 return false; 2374} 2375 2376/// \brief Checks whether the given template argument is the address 2377/// of an object or function according to C++ [temp.arg.nontype]p1. 2378static bool 2379CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S, 2380 NonTypeTemplateParmDecl *Param, 2381 QualType ParamType, 2382 Expr *ArgIn, 2383 TemplateArgument &Converted) { 2384 bool Invalid = false; 2385 Expr *Arg = ArgIn; 2386 QualType ArgType = Arg->getType(); 2387 2388 // See through any implicit casts we added to fix the type. 2389 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2390 Arg = Cast->getSubExpr(); 2391 2392 // C++ [temp.arg.nontype]p1: 2393 // 2394 // A template-argument for a non-type, non-template 2395 // template-parameter shall be one of: [...] 2396 // 2397 // -- the address of an object or function with external 2398 // linkage, including function templates and function 2399 // template-ids but excluding non-static class members, 2400 // expressed as & id-expression where the & is optional if 2401 // the name refers to a function or array, or if the 2402 // corresponding template-parameter is a reference; or 2403 DeclRefExpr *DRE = 0; 2404 2405 // Ignore (and complain about) any excess parentheses. 2406 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2407 if (!Invalid) { 2408 S.Diag(Arg->getSourceRange().getBegin(), 2409 diag::err_template_arg_extra_parens) 2410 << Arg->getSourceRange(); 2411 Invalid = true; 2412 } 2413 2414 Arg = Parens->getSubExpr(); 2415 } 2416 2417 bool AddressTaken = false; 2418 SourceLocation AddrOpLoc; 2419 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2420 if (UnOp->getOpcode() == UO_AddrOf) { 2421 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2422 AddressTaken = true; 2423 AddrOpLoc = UnOp->getOperatorLoc(); 2424 } 2425 } else 2426 DRE = dyn_cast<DeclRefExpr>(Arg); 2427 2428 if (!DRE) { 2429 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref) 2430 << Arg->getSourceRange(); 2431 S.Diag(Param->getLocation(), diag::note_template_param_here); 2432 return true; 2433 } 2434 2435 // Stop checking the precise nature of the argument if it is value dependent, 2436 // it should be checked when instantiated. 2437 if (Arg->isValueDependent()) { 2438 Converted = TemplateArgument(ArgIn->Retain()); 2439 return false; 2440 } 2441 2442 if (!isa<ValueDecl>(DRE->getDecl())) { 2443 S.Diag(Arg->getSourceRange().getBegin(), 2444 diag::err_template_arg_not_object_or_func_form) 2445 << Arg->getSourceRange(); 2446 S.Diag(Param->getLocation(), diag::note_template_param_here); 2447 return true; 2448 } 2449 2450 NamedDecl *Entity = 0; 2451 2452 // Cannot refer to non-static data members 2453 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) { 2454 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field) 2455 << Field << Arg->getSourceRange(); 2456 S.Diag(Param->getLocation(), diag::note_template_param_here); 2457 return true; 2458 } 2459 2460 // Cannot refer to non-static member functions 2461 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl())) 2462 if (!Method->isStatic()) { 2463 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method) 2464 << Method << Arg->getSourceRange(); 2465 S.Diag(Param->getLocation(), diag::note_template_param_here); 2466 return true; 2467 } 2468 2469 // Functions must have external linkage. 2470 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) { 2471 if (!isExternalLinkage(Func->getLinkage())) { 2472 S.Diag(Arg->getSourceRange().getBegin(), 2473 diag::err_template_arg_function_not_extern) 2474 << Func << Arg->getSourceRange(); 2475 S.Diag(Func->getLocation(), diag::note_template_arg_internal_object) 2476 << true; 2477 return true; 2478 } 2479 2480 // Okay: we've named a function with external linkage. 2481 Entity = Func; 2482 2483 // If the template parameter has pointer type, the function decays. 2484 if (ParamType->isPointerType() && !AddressTaken) 2485 ArgType = S.Context.getPointerType(Func->getType()); 2486 else if (AddressTaken && ParamType->isReferenceType()) { 2487 // If we originally had an address-of operator, but the 2488 // parameter has reference type, complain and (if things look 2489 // like they will work) drop the address-of operator. 2490 if (!S.Context.hasSameUnqualifiedType(Func->getType(), 2491 ParamType.getNonReferenceType())) { 2492 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2493 << ParamType; 2494 S.Diag(Param->getLocation(), diag::note_template_param_here); 2495 return true; 2496 } 2497 2498 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2499 << ParamType 2500 << FixItHint::CreateRemoval(AddrOpLoc); 2501 S.Diag(Param->getLocation(), diag::note_template_param_here); 2502 2503 ArgType = Func->getType(); 2504 } 2505 } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 2506 if (!isExternalLinkage(Var->getLinkage())) { 2507 S.Diag(Arg->getSourceRange().getBegin(), 2508 diag::err_template_arg_object_not_extern) 2509 << Var << Arg->getSourceRange(); 2510 S.Diag(Var->getLocation(), diag::note_template_arg_internal_object) 2511 << true; 2512 return true; 2513 } 2514 2515 // A value of reference type is not an object. 2516 if (Var->getType()->isReferenceType()) { 2517 S.Diag(Arg->getSourceRange().getBegin(), 2518 diag::err_template_arg_reference_var) 2519 << Var->getType() << Arg->getSourceRange(); 2520 S.Diag(Param->getLocation(), diag::note_template_param_here); 2521 return true; 2522 } 2523 2524 // Okay: we've named an object with external linkage 2525 Entity = Var; 2526 2527 // If the template parameter has pointer type, we must have taken 2528 // the address of this object. 2529 if (ParamType->isReferenceType()) { 2530 if (AddressTaken) { 2531 // If we originally had an address-of operator, but the 2532 // parameter has reference type, complain and (if things look 2533 // like they will work) drop the address-of operator. 2534 if (!S.Context.hasSameUnqualifiedType(Var->getType(), 2535 ParamType.getNonReferenceType())) { 2536 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2537 << ParamType; 2538 S.Diag(Param->getLocation(), diag::note_template_param_here); 2539 return true; 2540 } 2541 2542 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2543 << ParamType 2544 << FixItHint::CreateRemoval(AddrOpLoc); 2545 S.Diag(Param->getLocation(), diag::note_template_param_here); 2546 2547 ArgType = Var->getType(); 2548 } 2549 } else if (!AddressTaken && ParamType->isPointerType()) { 2550 if (Var->getType()->isArrayType()) { 2551 // Array-to-pointer decay. 2552 ArgType = S.Context.getArrayDecayedType(Var->getType()); 2553 } else { 2554 // If the template parameter has pointer type but the address of 2555 // this object was not taken, complain and (possibly) recover by 2556 // taking the address of the entity. 2557 ArgType = S.Context.getPointerType(Var->getType()); 2558 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) { 2559 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2560 << ParamType; 2561 S.Diag(Param->getLocation(), diag::note_template_param_here); 2562 return true; 2563 } 2564 2565 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2566 << ParamType 2567 << FixItHint::CreateInsertion(Arg->getLocStart(), "&"); 2568 2569 S.Diag(Param->getLocation(), diag::note_template_param_here); 2570 } 2571 } 2572 } else { 2573 // We found something else, but we don't know specifically what it is. 2574 S.Diag(Arg->getSourceRange().getBegin(), 2575 diag::err_template_arg_not_object_or_func) 2576 << Arg->getSourceRange(); 2577 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); 2578 return true; 2579 } 2580 2581 if (ParamType->isPointerType() && 2582 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() && 2583 S.IsQualificationConversion(ArgType, ParamType)) { 2584 // For pointer-to-object types, qualification conversions are 2585 // permitted. 2586 } else { 2587 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) { 2588 if (!ParamRef->getPointeeType()->isFunctionType()) { 2589 // C++ [temp.arg.nontype]p5b3: 2590 // For a non-type template-parameter of type reference to 2591 // object, no conversions apply. The type referred to by the 2592 // reference may be more cv-qualified than the (otherwise 2593 // identical) type of the template- argument. The 2594 // template-parameter is bound directly to the 2595 // template-argument, which shall be an lvalue. 2596 2597 // FIXME: Other qualifiers? 2598 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers(); 2599 unsigned ArgQuals = ArgType.getCVRQualifiers(); 2600 2601 if ((ParamQuals | ArgQuals) != ParamQuals) { 2602 S.Diag(Arg->getSourceRange().getBegin(), 2603 diag::err_template_arg_ref_bind_ignores_quals) 2604 << ParamType << Arg->getType() 2605 << Arg->getSourceRange(); 2606 S.Diag(Param->getLocation(), diag::note_template_param_here); 2607 return true; 2608 } 2609 } 2610 } 2611 2612 // At this point, the template argument refers to an object or 2613 // function with external linkage. We now need to check whether the 2614 // argument and parameter types are compatible. 2615 if (!S.Context.hasSameUnqualifiedType(ArgType, 2616 ParamType.getNonReferenceType())) { 2617 // We can't perform this conversion or binding. 2618 if (ParamType->isReferenceType()) 2619 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind) 2620 << ParamType << Arg->getType() << Arg->getSourceRange(); 2621 else 2622 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible) 2623 << Arg->getType() << ParamType << Arg->getSourceRange(); 2624 S.Diag(Param->getLocation(), diag::note_template_param_here); 2625 return true; 2626 } 2627 } 2628 2629 // Create the template argument. 2630 Converted = TemplateArgument(Entity->getCanonicalDecl()); 2631 S.MarkDeclarationReferenced(Arg->getLocStart(), Entity); 2632 return false; 2633} 2634 2635/// \brief Checks whether the given template argument is a pointer to 2636/// member constant according to C++ [temp.arg.nontype]p1. 2637bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, 2638 TemplateArgument &Converted) { 2639 bool Invalid = false; 2640 2641 // See through any implicit casts we added to fix the type. 2642 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2643 Arg = Cast->getSubExpr(); 2644 2645 // C++ [temp.arg.nontype]p1: 2646 // 2647 // A template-argument for a non-type, non-template 2648 // template-parameter shall be one of: [...] 2649 // 2650 // -- a pointer to member expressed as described in 5.3.1. 2651 DeclRefExpr *DRE = 0; 2652 2653 // Ignore (and complain about) any excess parentheses. 2654 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2655 if (!Invalid) { 2656 Diag(Arg->getSourceRange().getBegin(), 2657 diag::err_template_arg_extra_parens) 2658 << Arg->getSourceRange(); 2659 Invalid = true; 2660 } 2661 2662 Arg = Parens->getSubExpr(); 2663 } 2664 2665 // A pointer-to-member constant written &Class::member. 2666 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2667 if (UnOp->getOpcode() == UO_AddrOf) { 2668 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2669 if (DRE && !DRE->getQualifier()) 2670 DRE = 0; 2671 } 2672 } 2673 // A constant of pointer-to-member type. 2674 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { 2675 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { 2676 if (VD->getType()->isMemberPointerType()) { 2677 if (isa<NonTypeTemplateParmDecl>(VD) || 2678 (isa<VarDecl>(VD) && 2679 Context.getCanonicalType(VD->getType()).isConstQualified())) { 2680 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2681 Converted = TemplateArgument(Arg->Retain()); 2682 else 2683 Converted = TemplateArgument(VD->getCanonicalDecl()); 2684 return Invalid; 2685 } 2686 } 2687 } 2688 2689 DRE = 0; 2690 } 2691 2692 if (!DRE) 2693 return Diag(Arg->getSourceRange().getBegin(), 2694 diag::err_template_arg_not_pointer_to_member_form) 2695 << Arg->getSourceRange(); 2696 2697 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { 2698 assert((isa<FieldDecl>(DRE->getDecl()) || 2699 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && 2700 "Only non-static member pointers can make it here"); 2701 2702 // Okay: this is the address of a non-static member, and therefore 2703 // a member pointer constant. 2704 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2705 Converted = TemplateArgument(Arg->Retain()); 2706 else 2707 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); 2708 return Invalid; 2709 } 2710 2711 // We found something else, but we don't know specifically what it is. 2712 Diag(Arg->getSourceRange().getBegin(), 2713 diag::err_template_arg_not_pointer_to_member_form) 2714 << Arg->getSourceRange(); 2715 Diag(DRE->getDecl()->getLocation(), 2716 diag::note_template_arg_refers_here); 2717 return true; 2718} 2719 2720/// \brief Check a template argument against its corresponding 2721/// non-type template parameter. 2722/// 2723/// This routine implements the semantics of C++ [temp.arg.nontype]. 2724/// It returns true if an error occurred, and false otherwise. \p 2725/// InstantiatedParamType is the type of the non-type template 2726/// parameter after it has been instantiated. 2727/// 2728/// If no error was detected, Converted receives the converted template argument. 2729bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, 2730 QualType InstantiatedParamType, Expr *&Arg, 2731 TemplateArgument &Converted, 2732 CheckTemplateArgumentKind CTAK) { 2733 SourceLocation StartLoc = Arg->getSourceRange().getBegin(); 2734 2735 // If either the parameter has a dependent type or the argument is 2736 // type-dependent, there's nothing we can check now. 2737 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { 2738 // FIXME: Produce a cloned, canonical expression? 2739 Converted = TemplateArgument(Arg); 2740 return false; 2741 } 2742 2743 // C++ [temp.arg.nontype]p5: 2744 // The following conversions are performed on each expression used 2745 // as a non-type template-argument. If a non-type 2746 // template-argument cannot be converted to the type of the 2747 // corresponding template-parameter then the program is 2748 // ill-formed. 2749 // 2750 // -- for a non-type template-parameter of integral or 2751 // enumeration type, integral promotions (4.5) and integral 2752 // conversions (4.7) are applied. 2753 QualType ParamType = InstantiatedParamType; 2754 QualType ArgType = Arg->getType(); 2755 if (ParamType->isIntegralOrEnumerationType()) { 2756 // C++ [temp.arg.nontype]p1: 2757 // A template-argument for a non-type, non-template 2758 // template-parameter shall be one of: 2759 // 2760 // -- an integral constant-expression of integral or enumeration 2761 // type; or 2762 // -- the name of a non-type template-parameter; or 2763 SourceLocation NonConstantLoc; 2764 llvm::APSInt Value; 2765 if (!ArgType->isIntegralOrEnumerationType()) { 2766 Diag(Arg->getSourceRange().getBegin(), 2767 diag::err_template_arg_not_integral_or_enumeral) 2768 << ArgType << Arg->getSourceRange(); 2769 Diag(Param->getLocation(), diag::note_template_param_here); 2770 return true; 2771 } else if (!Arg->isValueDependent() && 2772 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) { 2773 Diag(NonConstantLoc, diag::err_template_arg_not_ice) 2774 << ArgType << Arg->getSourceRange(); 2775 return true; 2776 } 2777 2778 // From here on out, all we care about are the unqualified forms 2779 // of the parameter and argument types. 2780 ParamType = ParamType.getUnqualifiedType(); 2781 ArgType = ArgType.getUnqualifiedType(); 2782 2783 // Try to convert the argument to the parameter's type. 2784 if (Context.hasSameType(ParamType, ArgType)) { 2785 // Okay: no conversion necessary 2786 } else if (CTAK == CTAK_Deduced) { 2787 // C++ [temp.deduct.type]p17: 2788 // If, in the declaration of a function template with a non-type 2789 // template-parameter, the non-type template- parameter is used 2790 // in an expression in the function parameter-list and, if the 2791 // corresponding template-argument is deduced, the 2792 // template-argument type shall match the type of the 2793 // template-parameter exactly, except that a template-argument 2794 // deduced from an array bound may be of any integral type. 2795 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch) 2796 << ArgType << ParamType; 2797 Diag(Param->getLocation(), diag::note_template_param_here); 2798 return true; 2799 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || 2800 !ParamType->isEnumeralType()) { 2801 // This is an integral promotion or conversion. 2802 ImpCastExprToType(Arg, ParamType, CK_IntegralCast); 2803 } else { 2804 // We can't perform this conversion. 2805 Diag(Arg->getSourceRange().getBegin(), 2806 diag::err_template_arg_not_convertible) 2807 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2808 Diag(Param->getLocation(), diag::note_template_param_here); 2809 return true; 2810 } 2811 2812 QualType IntegerType = Context.getCanonicalType(ParamType); 2813 if (const EnumType *Enum = IntegerType->getAs<EnumType>()) 2814 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); 2815 2816 if (!Arg->isValueDependent()) { 2817 llvm::APSInt OldValue = Value; 2818 2819 // Coerce the template argument's value to the value it will have 2820 // based on the template parameter's type. 2821 unsigned AllowedBits = Context.getTypeSize(IntegerType); 2822 if (Value.getBitWidth() != AllowedBits) 2823 Value.extOrTrunc(AllowedBits); 2824 Value.setIsSigned(IntegerType->isSignedIntegerType()); 2825 2826 // Complain if an unsigned parameter received a negative value. 2827 if (IntegerType->isUnsignedIntegerType() 2828 && (OldValue.isSigned() && OldValue.isNegative())) { 2829 Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative) 2830 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2831 << Arg->getSourceRange(); 2832 Diag(Param->getLocation(), diag::note_template_param_here); 2833 } 2834 2835 // Complain if we overflowed the template parameter's type. 2836 unsigned RequiredBits; 2837 if (IntegerType->isUnsignedIntegerType()) 2838 RequiredBits = OldValue.getActiveBits(); 2839 else if (OldValue.isUnsigned()) 2840 RequiredBits = OldValue.getActiveBits() + 1; 2841 else 2842 RequiredBits = OldValue.getMinSignedBits(); 2843 if (RequiredBits > AllowedBits) { 2844 Diag(Arg->getSourceRange().getBegin(), 2845 diag::warn_template_arg_too_large) 2846 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2847 << Arg->getSourceRange(); 2848 Diag(Param->getLocation(), diag::note_template_param_here); 2849 } 2850 } 2851 2852 // Add the value of this argument to the list of converted 2853 // arguments. We use the bitwidth and signedness of the template 2854 // parameter. 2855 if (Arg->isValueDependent()) { 2856 // The argument is value-dependent. Create a new 2857 // TemplateArgument with the converted expression. 2858 Converted = TemplateArgument(Arg); 2859 return false; 2860 } 2861 2862 Converted = TemplateArgument(Value, 2863 ParamType->isEnumeralType() ? ParamType 2864 : IntegerType); 2865 return false; 2866 } 2867 2868 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction 2869 2870 // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion 2871 // from a template argument of type std::nullptr_t to a non-type 2872 // template parameter of type pointer to object, pointer to 2873 // function, or pointer-to-member, respectively. 2874 if (ArgType->isNullPtrType() && 2875 (ParamType->isPointerType() || ParamType->isMemberPointerType())) { 2876 Converted = TemplateArgument((NamedDecl *)0); 2877 return false; 2878 } 2879 2880 // Handle pointer-to-function, reference-to-function, and 2881 // pointer-to-member-function all in (roughly) the same way. 2882 if (// -- For a non-type template-parameter of type pointer to 2883 // function, only the function-to-pointer conversion (4.3) is 2884 // applied. If the template-argument represents a set of 2885 // overloaded functions (or a pointer to such), the matching 2886 // function is selected from the set (13.4). 2887 (ParamType->isPointerType() && 2888 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || 2889 // -- For a non-type template-parameter of type reference to 2890 // function, no conversions apply. If the template-argument 2891 // represents a set of overloaded functions, the matching 2892 // function is selected from the set (13.4). 2893 (ParamType->isReferenceType() && 2894 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || 2895 // -- For a non-type template-parameter of type pointer to 2896 // member function, no conversions apply. If the 2897 // template-argument represents a set of overloaded member 2898 // functions, the matching member function is selected from 2899 // the set (13.4). 2900 (ParamType->isMemberPointerType() && 2901 ParamType->getAs<MemberPointerType>()->getPointeeType() 2902 ->isFunctionType())) { 2903 2904 if (Arg->getType() == Context.OverloadTy) { 2905 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType, 2906 true, 2907 FoundResult)) { 2908 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2909 return true; 2910 2911 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2912 ArgType = Arg->getType(); 2913 } else 2914 return true; 2915 } 2916 2917 if (!ParamType->isMemberPointerType()) 2918 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2919 ParamType, 2920 Arg, Converted); 2921 2922 if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType())) { 2923 ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg)); 2924 } else if (!Context.hasSameUnqualifiedType(ArgType, 2925 ParamType.getNonReferenceType())) { 2926 // We can't perform this conversion. 2927 Diag(Arg->getSourceRange().getBegin(), 2928 diag::err_template_arg_not_convertible) 2929 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2930 Diag(Param->getLocation(), diag::note_template_param_here); 2931 return true; 2932 } 2933 2934 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2935 } 2936 2937 if (ParamType->isPointerType()) { 2938 // -- for a non-type template-parameter of type pointer to 2939 // object, qualification conversions (4.4) and the 2940 // array-to-pointer conversion (4.2) are applied. 2941 // C++0x also allows a value of std::nullptr_t. 2942 assert(ParamType->getPointeeType()->isIncompleteOrObjectType() && 2943 "Only object pointers allowed here"); 2944 2945 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2946 ParamType, 2947 Arg, Converted); 2948 } 2949 2950 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { 2951 // -- For a non-type template-parameter of type reference to 2952 // object, no conversions apply. The type referred to by the 2953 // reference may be more cv-qualified than the (otherwise 2954 // identical) type of the template-argument. The 2955 // template-parameter is bound directly to the 2956 // template-argument, which must be an lvalue. 2957 assert(ParamRefType->getPointeeType()->isIncompleteOrObjectType() && 2958 "Only object references allowed here"); 2959 2960 if (Arg->getType() == Context.OverloadTy) { 2961 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, 2962 ParamRefType->getPointeeType(), 2963 true, 2964 FoundResult)) { 2965 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2966 return true; 2967 2968 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2969 ArgType = Arg->getType(); 2970 } else 2971 return true; 2972 } 2973 2974 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2975 ParamType, 2976 Arg, Converted); 2977 } 2978 2979 // -- For a non-type template-parameter of type pointer to data 2980 // member, qualification conversions (4.4) are applied. 2981 assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); 2982 2983 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) { 2984 // Types match exactly: nothing more to do here. 2985 } else if (IsQualificationConversion(ArgType, ParamType)) { 2986 ImpCastExprToType(Arg, ParamType, CK_NoOp, CastCategory(Arg)); 2987 } else { 2988 // We can't perform this conversion. 2989 Diag(Arg->getSourceRange().getBegin(), 2990 diag::err_template_arg_not_convertible) 2991 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2992 Diag(Param->getLocation(), diag::note_template_param_here); 2993 return true; 2994 } 2995 2996 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2997} 2998 2999/// \brief Check a template argument against its corresponding 3000/// template template parameter. 3001/// 3002/// This routine implements the semantics of C++ [temp.arg.template]. 3003/// It returns true if an error occurred, and false otherwise. 3004bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, 3005 const TemplateArgumentLoc &Arg) { 3006 TemplateName Name = Arg.getArgument().getAsTemplate(); 3007 TemplateDecl *Template = Name.getAsTemplateDecl(); 3008 if (!Template) { 3009 // Any dependent template name is fine. 3010 assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); 3011 return false; 3012 } 3013 3014 // C++ [temp.arg.template]p1: 3015 // A template-argument for a template template-parameter shall be 3016 // the name of a class template, expressed as id-expression. Only 3017 // primary class templates are considered when matching the 3018 // template template argument with the corresponding parameter; 3019 // partial specializations are not considered even if their 3020 // parameter lists match that of the template template parameter. 3021 // 3022 // Note that we also allow template template parameters here, which 3023 // will happen when we are dealing with, e.g., class template 3024 // partial specializations. 3025 if (!isa<ClassTemplateDecl>(Template) && 3026 !isa<TemplateTemplateParmDecl>(Template)) { 3027 assert(isa<FunctionTemplateDecl>(Template) && 3028 "Only function templates are possible here"); 3029 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); 3030 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) 3031 << Template; 3032 } 3033 3034 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), 3035 Param->getTemplateParameters(), 3036 true, 3037 TPL_TemplateTemplateArgumentMatch, 3038 Arg.getLocation()); 3039} 3040 3041/// \brief Given a non-type template argument that refers to a 3042/// declaration and the type of its corresponding non-type template 3043/// parameter, produce an expression that properly refers to that 3044/// declaration. 3045ExprResult 3046Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg, 3047 QualType ParamType, 3048 SourceLocation Loc) { 3049 assert(Arg.getKind() == TemplateArgument::Declaration && 3050 "Only declaration template arguments permitted here"); 3051 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl()); 3052 3053 if (VD->getDeclContext()->isRecord() && 3054 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) { 3055 // If the value is a class member, we might have a pointer-to-member. 3056 // Determine whether the non-type template template parameter is of 3057 // pointer-to-member type. If so, we need to build an appropriate 3058 // expression for a pointer-to-member, since a "normal" DeclRefExpr 3059 // would refer to the member itself. 3060 if (ParamType->isMemberPointerType()) { 3061 QualType ClassType 3062 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext())); 3063 NestedNameSpecifier *Qualifier 3064 = NestedNameSpecifier::Create(Context, 0, false, 3065 ClassType.getTypePtr()); 3066 CXXScopeSpec SS; 3067 SS.setScopeRep(Qualifier); 3068 ExprResult RefExpr = BuildDeclRefExpr(VD, 3069 VD->getType().getNonReferenceType(), 3070 Loc, 3071 &SS); 3072 if (RefExpr.isInvalid()) 3073 return ExprError(); 3074 3075 RefExpr = CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get()); 3076 3077 // We might need to perform a trailing qualification conversion, since 3078 // the element type on the parameter could be more qualified than the 3079 // element type in the expression we constructed. 3080 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(), 3081 ParamType.getUnqualifiedType())) { 3082 Expr *RefE = RefExpr.takeAs<Expr>(); 3083 ImpCastExprToType(RefE, ParamType.getUnqualifiedType(), CK_NoOp); 3084 RefExpr = Owned(RefE); 3085 } 3086 3087 assert(!RefExpr.isInvalid() && 3088 Context.hasSameType(((Expr*) RefExpr.get())->getType(), 3089 ParamType.getUnqualifiedType())); 3090 return move(RefExpr); 3091 } 3092 } 3093 3094 QualType T = VD->getType().getNonReferenceType(); 3095 if (ParamType->isPointerType()) { 3096 // When the non-type template parameter is a pointer, take the 3097 // address of the declaration. 3098 ExprResult RefExpr = BuildDeclRefExpr(VD, T, Loc); 3099 if (RefExpr.isInvalid()) 3100 return ExprError(); 3101 3102 if (T->isFunctionType() || T->isArrayType()) { 3103 // Decay functions and arrays. 3104 Expr *RefE = (Expr *)RefExpr.get(); 3105 DefaultFunctionArrayConversion(RefE); 3106 if (RefE != RefExpr.get()) { 3107 RefExpr.release(); 3108 RefExpr = Owned(RefE); 3109 } 3110 3111 return move(RefExpr); 3112 } 3113 3114 // Take the address of everything else 3115 return CreateBuiltinUnaryOp(Loc, UO_AddrOf, RefExpr.get()); 3116 } 3117 3118 // If the non-type template parameter has reference type, qualify the 3119 // resulting declaration reference with the extra qualifiers on the 3120 // type that the reference refers to. 3121 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) 3122 T = Context.getQualifiedType(T, TargetRef->getPointeeType().getQualifiers()); 3123 3124 return BuildDeclRefExpr(VD, T, Loc); 3125} 3126 3127/// \brief Construct a new expression that refers to the given 3128/// integral template argument with the given source-location 3129/// information. 3130/// 3131/// This routine takes care of the mapping from an integral template 3132/// argument (which may have any integral type) to the appropriate 3133/// literal value. 3134ExprResult 3135Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg, 3136 SourceLocation Loc) { 3137 assert(Arg.getKind() == TemplateArgument::Integral && 3138 "Operation is only value for integral template arguments"); 3139 QualType T = Arg.getIntegralType(); 3140 if (T->isCharType() || T->isWideCharType()) 3141 return Owned(new (Context) CharacterLiteral( 3142 Arg.getAsIntegral()->getZExtValue(), 3143 T->isWideCharType(), 3144 T, 3145 Loc)); 3146 if (T->isBooleanType()) 3147 return Owned(new (Context) CXXBoolLiteralExpr( 3148 Arg.getAsIntegral()->getBoolValue(), 3149 T, 3150 Loc)); 3151 3152 return Owned(new (Context) IntegerLiteral(*Arg.getAsIntegral(), T, Loc)); 3153} 3154 3155 3156/// \brief Determine whether the given template parameter lists are 3157/// equivalent. 3158/// 3159/// \param New The new template parameter list, typically written in the 3160/// source code as part of a new template declaration. 3161/// 3162/// \param Old The old template parameter list, typically found via 3163/// name lookup of the template declared with this template parameter 3164/// list. 3165/// 3166/// \param Complain If true, this routine will produce a diagnostic if 3167/// the template parameter lists are not equivalent. 3168/// 3169/// \param Kind describes how we are to match the template parameter lists. 3170/// 3171/// \param TemplateArgLoc If this source location is valid, then we 3172/// are actually checking the template parameter list of a template 3173/// argument (New) against the template parameter list of its 3174/// corresponding template template parameter (Old). We produce 3175/// slightly different diagnostics in this scenario. 3176/// 3177/// \returns True if the template parameter lists are equal, false 3178/// otherwise. 3179bool 3180Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, 3181 TemplateParameterList *Old, 3182 bool Complain, 3183 TemplateParameterListEqualKind Kind, 3184 SourceLocation TemplateArgLoc) { 3185 if (Old->size() != New->size()) { 3186 if (Complain) { 3187 unsigned NextDiag = diag::err_template_param_list_different_arity; 3188 if (TemplateArgLoc.isValid()) { 3189 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3190 NextDiag = diag::note_template_param_list_different_arity; 3191 } 3192 Diag(New->getTemplateLoc(), NextDiag) 3193 << (New->size() > Old->size()) 3194 << (Kind != TPL_TemplateMatch) 3195 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); 3196 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) 3197 << (Kind != TPL_TemplateMatch) 3198 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); 3199 } 3200 3201 return false; 3202 } 3203 3204 for (TemplateParameterList::iterator OldParm = Old->begin(), 3205 OldParmEnd = Old->end(), NewParm = New->begin(); 3206 OldParm != OldParmEnd; ++OldParm, ++NewParm) { 3207 if ((*OldParm)->getKind() != (*NewParm)->getKind()) { 3208 if (Complain) { 3209 unsigned NextDiag = diag::err_template_param_different_kind; 3210 if (TemplateArgLoc.isValid()) { 3211 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3212 NextDiag = diag::note_template_param_different_kind; 3213 } 3214 Diag((*NewParm)->getLocation(), NextDiag) 3215 << (Kind != TPL_TemplateMatch); 3216 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration) 3217 << (Kind != TPL_TemplateMatch); 3218 } 3219 return false; 3220 } 3221 3222 if (TemplateTypeParmDecl *OldTTP 3223 = dyn_cast<TemplateTypeParmDecl>(*OldParm)) { 3224 // Template type parameters are equivalent if either both are template 3225 // type parameter packs or neither are (since we know we're at the same 3226 // index). 3227 TemplateTypeParmDecl *NewTTP = cast<TemplateTypeParmDecl>(*NewParm); 3228 if (OldTTP->isParameterPack() != NewTTP->isParameterPack()) { 3229 // FIXME: Implement the rules in C++0x [temp.arg.template]p5 that 3230 // allow one to match a template parameter pack in the template 3231 // parameter list of a template template parameter to one or more 3232 // template parameters in the template parameter list of the 3233 // corresponding template template argument. 3234 if (Complain) { 3235 unsigned NextDiag = diag::err_template_parameter_pack_non_pack; 3236 if (TemplateArgLoc.isValid()) { 3237 Diag(TemplateArgLoc, 3238 diag::err_template_arg_template_params_mismatch); 3239 NextDiag = diag::note_template_parameter_pack_non_pack; 3240 } 3241 Diag(NewTTP->getLocation(), NextDiag) 3242 << 0 << NewTTP->isParameterPack(); 3243 Diag(OldTTP->getLocation(), diag::note_template_parameter_pack_here) 3244 << 0 << OldTTP->isParameterPack(); 3245 } 3246 return false; 3247 } 3248 } else if (NonTypeTemplateParmDecl *OldNTTP 3249 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) { 3250 // The types of non-type template parameters must agree. 3251 NonTypeTemplateParmDecl *NewNTTP 3252 = cast<NonTypeTemplateParmDecl>(*NewParm); 3253 3254 // If we are matching a template template argument to a template 3255 // template parameter and one of the non-type template parameter types 3256 // is dependent, then we must wait until template instantiation time 3257 // to actually compare the arguments. 3258 if (Kind == TPL_TemplateTemplateArgumentMatch && 3259 (OldNTTP->getType()->isDependentType() || 3260 NewNTTP->getType()->isDependentType())) 3261 continue; 3262 3263 if (Context.getCanonicalType(OldNTTP->getType()) != 3264 Context.getCanonicalType(NewNTTP->getType())) { 3265 if (Complain) { 3266 unsigned NextDiag = diag::err_template_nontype_parm_different_type; 3267 if (TemplateArgLoc.isValid()) { 3268 Diag(TemplateArgLoc, 3269 diag::err_template_arg_template_params_mismatch); 3270 NextDiag = diag::note_template_nontype_parm_different_type; 3271 } 3272 Diag(NewNTTP->getLocation(), NextDiag) 3273 << NewNTTP->getType() 3274 << (Kind != TPL_TemplateMatch); 3275 Diag(OldNTTP->getLocation(), 3276 diag::note_template_nontype_parm_prev_declaration) 3277 << OldNTTP->getType(); 3278 } 3279 return false; 3280 } 3281 } else { 3282 // The template parameter lists of template template 3283 // parameters must agree. 3284 assert(isa<TemplateTemplateParmDecl>(*OldParm) && 3285 "Only template template parameters handled here"); 3286 TemplateTemplateParmDecl *OldTTP 3287 = cast<TemplateTemplateParmDecl>(*OldParm); 3288 TemplateTemplateParmDecl *NewTTP 3289 = cast<TemplateTemplateParmDecl>(*NewParm); 3290 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), 3291 OldTTP->getTemplateParameters(), 3292 Complain, 3293 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind), 3294 TemplateArgLoc)) 3295 return false; 3296 } 3297 } 3298 3299 return true; 3300} 3301 3302/// \brief Check whether a template can be declared within this scope. 3303/// 3304/// If the template declaration is valid in this scope, returns 3305/// false. Otherwise, issues a diagnostic and returns true. 3306bool 3307Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { 3308 // Find the nearest enclosing declaration scope. 3309 while ((S->getFlags() & Scope::DeclScope) == 0 || 3310 (S->getFlags() & Scope::TemplateParamScope) != 0) 3311 S = S->getParent(); 3312 3313 // C++ [temp]p2: 3314 // A template-declaration can appear only as a namespace scope or 3315 // class scope declaration. 3316 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 3317 if (Ctx && isa<LinkageSpecDecl>(Ctx) && 3318 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) 3319 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) 3320 << TemplateParams->getSourceRange(); 3321 3322 while (Ctx && isa<LinkageSpecDecl>(Ctx)) 3323 Ctx = Ctx->getParent(); 3324 3325 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) 3326 return false; 3327 3328 return Diag(TemplateParams->getTemplateLoc(), 3329 diag::err_template_outside_namespace_or_class_scope) 3330 << TemplateParams->getSourceRange(); 3331} 3332 3333/// \brief Determine what kind of template specialization the given declaration 3334/// is. 3335static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) { 3336 if (!D) 3337 return TSK_Undeclared; 3338 3339 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) 3340 return Record->getTemplateSpecializationKind(); 3341 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) 3342 return Function->getTemplateSpecializationKind(); 3343 if (VarDecl *Var = dyn_cast<VarDecl>(D)) 3344 return Var->getTemplateSpecializationKind(); 3345 3346 return TSK_Undeclared; 3347} 3348 3349/// \brief Check whether a specialization is well-formed in the current 3350/// context. 3351/// 3352/// This routine determines whether a template specialization can be declared 3353/// in the current context (C++ [temp.expl.spec]p2). 3354/// 3355/// \param S the semantic analysis object for which this check is being 3356/// performed. 3357/// 3358/// \param Specialized the entity being specialized or instantiated, which 3359/// may be a kind of template (class template, function template, etc.) or 3360/// a member of a class template (member function, static data member, 3361/// member class). 3362/// 3363/// \param PrevDecl the previous declaration of this entity, if any. 3364/// 3365/// \param Loc the location of the explicit specialization or instantiation of 3366/// this entity. 3367/// 3368/// \param IsPartialSpecialization whether this is a partial specialization of 3369/// a class template. 3370/// 3371/// \returns true if there was an error that we cannot recover from, false 3372/// otherwise. 3373static bool CheckTemplateSpecializationScope(Sema &S, 3374 NamedDecl *Specialized, 3375 NamedDecl *PrevDecl, 3376 SourceLocation Loc, 3377 bool IsPartialSpecialization) { 3378 // Keep these "kind" numbers in sync with the %select statements in the 3379 // various diagnostics emitted by this routine. 3380 int EntityKind = 0; 3381 bool isTemplateSpecialization = false; 3382 if (isa<ClassTemplateDecl>(Specialized)) { 3383 EntityKind = IsPartialSpecialization? 1 : 0; 3384 isTemplateSpecialization = true; 3385 } else if (isa<FunctionTemplateDecl>(Specialized)) { 3386 EntityKind = 2; 3387 isTemplateSpecialization = true; 3388 } else if (isa<CXXMethodDecl>(Specialized)) 3389 EntityKind = 3; 3390 else if (isa<VarDecl>(Specialized)) 3391 EntityKind = 4; 3392 else if (isa<RecordDecl>(Specialized)) 3393 EntityKind = 5; 3394 else { 3395 S.Diag(Loc, diag::err_template_spec_unknown_kind); 3396 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3397 return true; 3398 } 3399 3400 // C++ [temp.expl.spec]p2: 3401 // An explicit specialization shall be declared in the namespace 3402 // of which the template is a member, or, for member templates, in 3403 // the namespace of which the enclosing class or enclosing class 3404 // template is a member. An explicit specialization of a member 3405 // function, member class or static data member of a class 3406 // template shall be declared in the namespace of which the class 3407 // template is a member. Such a declaration may also be a 3408 // definition. If the declaration is not a definition, the 3409 // specialization may be defined later in the name- space in which 3410 // the explicit specialization was declared, or in a namespace 3411 // that encloses the one in which the explicit specialization was 3412 // declared. 3413 if (S.CurContext->getLookupContext()->isFunctionOrMethod()) { 3414 S.Diag(Loc, diag::err_template_spec_decl_function_scope) 3415 << Specialized; 3416 return true; 3417 } 3418 3419 if (S.CurContext->isRecord() && !IsPartialSpecialization) { 3420 S.Diag(Loc, diag::err_template_spec_decl_class_scope) 3421 << Specialized; 3422 return true; 3423 } 3424 3425 // C++ [temp.class.spec]p6: 3426 // A class template partial specialization may be declared or redeclared 3427 // in any namespace scope in which its definition may be defined (14.5.1 3428 // and 14.5.2). 3429 bool ComplainedAboutScope = false; 3430 DeclContext *SpecializedContext 3431 = Specialized->getDeclContext()->getEnclosingNamespaceContext(); 3432 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); 3433 if ((!PrevDecl || 3434 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || 3435 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ 3436 // There is no prior declaration of this entity, so this 3437 // specialization must be in the same context as the template 3438 // itself. 3439 if (!DC->Equals(SpecializedContext)) { 3440 if (isa<TranslationUnitDecl>(SpecializedContext)) 3441 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) 3442 << EntityKind << Specialized; 3443 else if (isa<NamespaceDecl>(SpecializedContext)) 3444 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope) 3445 << EntityKind << Specialized 3446 << cast<NamedDecl>(SpecializedContext); 3447 3448 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3449 ComplainedAboutScope = true; 3450 } 3451 } 3452 3453 // Make sure that this redeclaration (or definition) occurs in an enclosing 3454 // namespace. 3455 // Note that HandleDeclarator() performs this check for explicit 3456 // specializations of function templates, static data members, and member 3457 // functions, so we skip the check here for those kinds of entities. 3458 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. 3459 // Should we refactor that check, so that it occurs later? 3460 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && 3461 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || 3462 isa<FunctionDecl>(Specialized))) { 3463 if (isa<TranslationUnitDecl>(SpecializedContext)) 3464 S.Diag(Loc, diag::err_template_spec_redecl_global_scope) 3465 << EntityKind << Specialized; 3466 else if (isa<NamespaceDecl>(SpecializedContext)) 3467 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) 3468 << EntityKind << Specialized 3469 << cast<NamedDecl>(SpecializedContext); 3470 3471 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3472 } 3473 3474 // FIXME: check for specialization-after-instantiation errors and such. 3475 3476 return false; 3477} 3478 3479/// \brief Check the non-type template arguments of a class template 3480/// partial specialization according to C++ [temp.class.spec]p9. 3481/// 3482/// \param TemplateParams the template parameters of the primary class 3483/// template. 3484/// 3485/// \param TemplateArg the template arguments of the class template 3486/// partial specialization. 3487/// 3488/// \param MirrorsPrimaryTemplate will be set true if the class 3489/// template partial specialization arguments are identical to the 3490/// implicit template arguments of the primary template. This is not 3491/// necessarily an error (C++0x), and it is left to the caller to diagnose 3492/// this condition when it is an error. 3493/// 3494/// \returns true if there was an error, false otherwise. 3495bool Sema::CheckClassTemplatePartialSpecializationArgs( 3496 TemplateParameterList *TemplateParams, 3497 const TemplateArgumentListBuilder &TemplateArgs, 3498 bool &MirrorsPrimaryTemplate) { 3499 // FIXME: the interface to this function will have to change to 3500 // accommodate variadic templates. 3501 MirrorsPrimaryTemplate = true; 3502 3503 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments(); 3504 3505 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3506 // Determine whether the template argument list of the partial 3507 // specialization is identical to the implicit argument list of 3508 // the primary template. The caller may need to diagnostic this as 3509 // an error per C++ [temp.class.spec]p9b3. 3510 if (MirrorsPrimaryTemplate) { 3511 if (TemplateTypeParmDecl *TTP 3512 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) { 3513 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) != 3514 Context.getCanonicalType(ArgList[I].getAsType())) 3515 MirrorsPrimaryTemplate = false; 3516 } else if (TemplateTemplateParmDecl *TTP 3517 = dyn_cast<TemplateTemplateParmDecl>( 3518 TemplateParams->getParam(I))) { 3519 TemplateName Name = ArgList[I].getAsTemplate(); 3520 TemplateTemplateParmDecl *ArgDecl 3521 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()); 3522 if (!ArgDecl || 3523 ArgDecl->getIndex() != TTP->getIndex() || 3524 ArgDecl->getDepth() != TTP->getDepth()) 3525 MirrorsPrimaryTemplate = false; 3526 } 3527 } 3528 3529 NonTypeTemplateParmDecl *Param 3530 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); 3531 if (!Param) { 3532 continue; 3533 } 3534 3535 Expr *ArgExpr = ArgList[I].getAsExpr(); 3536 if (!ArgExpr) { 3537 MirrorsPrimaryTemplate = false; 3538 continue; 3539 } 3540 3541 // C++ [temp.class.spec]p8: 3542 // A non-type argument is non-specialized if it is the name of a 3543 // non-type parameter. All other non-type arguments are 3544 // specialized. 3545 // 3546 // Below, we check the two conditions that only apply to 3547 // specialized non-type arguments, so skip any non-specialized 3548 // arguments. 3549 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) 3550 if (NonTypeTemplateParmDecl *NTTP 3551 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) { 3552 if (MirrorsPrimaryTemplate && 3553 (Param->getIndex() != NTTP->getIndex() || 3554 Param->getDepth() != NTTP->getDepth())) 3555 MirrorsPrimaryTemplate = false; 3556 3557 continue; 3558 } 3559 3560 // C++ [temp.class.spec]p9: 3561 // Within the argument list of a class template partial 3562 // specialization, the following restrictions apply: 3563 // -- A partially specialized non-type argument expression 3564 // shall not involve a template parameter of the partial 3565 // specialization except when the argument expression is a 3566 // simple identifier. 3567 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { 3568 Diag(ArgExpr->getLocStart(), 3569 diag::err_dependent_non_type_arg_in_partial_spec) 3570 << ArgExpr->getSourceRange(); 3571 return true; 3572 } 3573 3574 // -- The type of a template parameter corresponding to a 3575 // specialized non-type argument shall not be dependent on a 3576 // parameter of the specialization. 3577 if (Param->getType()->isDependentType()) { 3578 Diag(ArgExpr->getLocStart(), 3579 diag::err_dependent_typed_non_type_arg_in_partial_spec) 3580 << Param->getType() 3581 << ArgExpr->getSourceRange(); 3582 Diag(Param->getLocation(), diag::note_template_param_here); 3583 return true; 3584 } 3585 3586 MirrorsPrimaryTemplate = false; 3587 } 3588 3589 return false; 3590} 3591 3592/// \brief Retrieve the previous declaration of the given declaration. 3593static NamedDecl *getPreviousDecl(NamedDecl *ND) { 3594 if (VarDecl *VD = dyn_cast<VarDecl>(ND)) 3595 return VD->getPreviousDeclaration(); 3596 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) 3597 return FD->getPreviousDeclaration(); 3598 if (TagDecl *TD = dyn_cast<TagDecl>(ND)) 3599 return TD->getPreviousDeclaration(); 3600 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND)) 3601 return TD->getPreviousDeclaration(); 3602 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND)) 3603 return FTD->getPreviousDeclaration(); 3604 if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND)) 3605 return CTD->getPreviousDeclaration(); 3606 return 0; 3607} 3608 3609DeclResult 3610Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, 3611 TagUseKind TUK, 3612 SourceLocation KWLoc, 3613 CXXScopeSpec &SS, 3614 TemplateTy TemplateD, 3615 SourceLocation TemplateNameLoc, 3616 SourceLocation LAngleLoc, 3617 ASTTemplateArgsPtr TemplateArgsIn, 3618 SourceLocation RAngleLoc, 3619 AttributeList *Attr, 3620 MultiTemplateParamsArg TemplateParameterLists) { 3621 assert(TUK != TUK_Reference && "References are not specializations"); 3622 3623 // Find the class template we're specializing 3624 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 3625 ClassTemplateDecl *ClassTemplate 3626 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); 3627 3628 if (!ClassTemplate) { 3629 Diag(TemplateNameLoc, diag::err_not_class_template_specialization) 3630 << (Name.getAsTemplateDecl() && 3631 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); 3632 return true; 3633 } 3634 3635 bool isExplicitSpecialization = false; 3636 bool isPartialSpecialization = false; 3637 3638 // Check the validity of the template headers that introduce this 3639 // template. 3640 // FIXME: We probably shouldn't complain about these headers for 3641 // friend declarations. 3642 bool Invalid = false; 3643 TemplateParameterList *TemplateParams 3644 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS, 3645 (TemplateParameterList**)TemplateParameterLists.get(), 3646 TemplateParameterLists.size(), 3647 TUK == TUK_Friend, 3648 isExplicitSpecialization, 3649 Invalid); 3650 if (Invalid) 3651 return true; 3652 3653 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 3654 if (TemplateParams) 3655 --NumMatchedTemplateParamLists; 3656 3657 if (TemplateParams && TemplateParams->size() > 0) { 3658 isPartialSpecialization = true; 3659 3660 // C++ [temp.class.spec]p10: 3661 // The template parameter list of a specialization shall not 3662 // contain default template argument values. 3663 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3664 Decl *Param = TemplateParams->getParam(I); 3665 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { 3666 if (TTP->hasDefaultArgument()) { 3667 Diag(TTP->getDefaultArgumentLoc(), 3668 diag::err_default_arg_in_partial_spec); 3669 TTP->removeDefaultArgument(); 3670 } 3671 } else if (NonTypeTemplateParmDecl *NTTP 3672 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 3673 if (Expr *DefArg = NTTP->getDefaultArgument()) { 3674 Diag(NTTP->getDefaultArgumentLoc(), 3675 diag::err_default_arg_in_partial_spec) 3676 << DefArg->getSourceRange(); 3677 NTTP->removeDefaultArgument(); 3678 } 3679 } else { 3680 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); 3681 if (TTP->hasDefaultArgument()) { 3682 Diag(TTP->getDefaultArgument().getLocation(), 3683 diag::err_default_arg_in_partial_spec) 3684 << TTP->getDefaultArgument().getSourceRange(); 3685 TTP->removeDefaultArgument(); 3686 } 3687 } 3688 } 3689 } else if (TemplateParams) { 3690 if (TUK == TUK_Friend) 3691 Diag(KWLoc, diag::err_template_spec_friend) 3692 << FixItHint::CreateRemoval( 3693 SourceRange(TemplateParams->getTemplateLoc(), 3694 TemplateParams->getRAngleLoc())) 3695 << SourceRange(LAngleLoc, RAngleLoc); 3696 else 3697 isExplicitSpecialization = true; 3698 } else if (TUK != TUK_Friend) { 3699 Diag(KWLoc, diag::err_template_spec_needs_header) 3700 << FixItHint::CreateInsertion(KWLoc, "template<> "); 3701 isExplicitSpecialization = true; 3702 } 3703 3704 // Check that the specialization uses the same tag kind as the 3705 // original template. 3706 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 3707 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!"); 3708 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 3709 Kind, KWLoc, 3710 *ClassTemplate->getIdentifier())) { 3711 Diag(KWLoc, diag::err_use_with_wrong_tag) 3712 << ClassTemplate 3713 << FixItHint::CreateReplacement(KWLoc, 3714 ClassTemplate->getTemplatedDecl()->getKindName()); 3715 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 3716 diag::note_previous_use); 3717 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 3718 } 3719 3720 // Translate the parser's template argument list in our AST format. 3721 TemplateArgumentListInfo TemplateArgs; 3722 TemplateArgs.setLAngleLoc(LAngleLoc); 3723 TemplateArgs.setRAngleLoc(RAngleLoc); 3724 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 3725 3726 // Check that the template argument list is well-formed for this 3727 // template. 3728 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 3729 TemplateArgs.size()); 3730 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 3731 TemplateArgs, false, Converted)) 3732 return true; 3733 3734 assert((Converted.structuredSize() == 3735 ClassTemplate->getTemplateParameters()->size()) && 3736 "Converted template argument list is too short!"); 3737 3738 // Find the class template (partial) specialization declaration that 3739 // corresponds to these arguments. 3740 if (isPartialSpecialization) { 3741 bool MirrorsPrimaryTemplate; 3742 if (CheckClassTemplatePartialSpecializationArgs( 3743 ClassTemplate->getTemplateParameters(), 3744 Converted, MirrorsPrimaryTemplate)) 3745 return true; 3746 3747 if (MirrorsPrimaryTemplate) { 3748 // C++ [temp.class.spec]p9b3: 3749 // 3750 // -- The argument list of the specialization shall not be identical 3751 // to the implicit argument list of the primary template. 3752 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) 3753 << (TUK == TUK_Definition) 3754 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc)); 3755 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, 3756 ClassTemplate->getIdentifier(), 3757 TemplateNameLoc, 3758 Attr, 3759 TemplateParams, 3760 AS_none); 3761 } 3762 3763 // FIXME: Diagnose friend partial specializations 3764 3765 if (!Name.isDependent() && 3766 !TemplateSpecializationType::anyDependentTemplateArguments( 3767 TemplateArgs.getArgumentArray(), 3768 TemplateArgs.size())) { 3769 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized) 3770 << ClassTemplate->getDeclName(); 3771 isPartialSpecialization = false; 3772 } 3773 } 3774 3775 void *InsertPos = 0; 3776 ClassTemplateSpecializationDecl *PrevDecl = 0; 3777 3778 if (isPartialSpecialization) 3779 // FIXME: Template parameter list matters, too 3780 PrevDecl 3781 = ClassTemplate->findPartialSpecialization(Converted.getFlatArguments(), 3782 Converted.flatSize(), 3783 InsertPos); 3784 else 3785 PrevDecl 3786 = ClassTemplate->findSpecialization(Converted.getFlatArguments(), 3787 Converted.flatSize(), InsertPos); 3788 3789 ClassTemplateSpecializationDecl *Specialization = 0; 3790 3791 // Check whether we can declare a class template specialization in 3792 // the current scope. 3793 if (TUK != TUK_Friend && 3794 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, 3795 TemplateNameLoc, 3796 isPartialSpecialization)) 3797 return true; 3798 3799 // The canonical type 3800 QualType CanonType; 3801 if (PrevDecl && 3802 (PrevDecl->getSpecializationKind() == TSK_Undeclared || 3803 TUK == TUK_Friend)) { 3804 // Since the only prior class template specialization with these 3805 // arguments was referenced but not declared, or we're only 3806 // referencing this specialization as a friend, reuse that 3807 // declaration node as our own, updating its source location to 3808 // reflect our new declaration. 3809 Specialization = PrevDecl; 3810 Specialization->setLocation(TemplateNameLoc); 3811 PrevDecl = 0; 3812 CanonType = Context.getTypeDeclType(Specialization); 3813 } else if (isPartialSpecialization) { 3814 // Build the canonical type that describes the converted template 3815 // arguments of the class template partial specialization. 3816 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); 3817 CanonType = Context.getTemplateSpecializationType(CanonTemplate, 3818 Converted.getFlatArguments(), 3819 Converted.flatSize()); 3820 3821 // Create a new class template partial specialization declaration node. 3822 ClassTemplatePartialSpecializationDecl *PrevPartial 3823 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); 3824 unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber() 3825 : ClassTemplate->getNextPartialSpecSequenceNumber(); 3826 ClassTemplatePartialSpecializationDecl *Partial 3827 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind, 3828 ClassTemplate->getDeclContext(), 3829 TemplateNameLoc, 3830 TemplateParams, 3831 ClassTemplate, 3832 Converted, 3833 TemplateArgs, 3834 CanonType, 3835 PrevPartial, 3836 SequenceNumber); 3837 SetNestedNameSpecifier(Partial, SS); 3838 if (NumMatchedTemplateParamLists > 0 && SS.isSet()) { 3839 Partial->setTemplateParameterListsInfo(Context, 3840 NumMatchedTemplateParamLists, 3841 (TemplateParameterList**) TemplateParameterLists.release()); 3842 } 3843 3844 if (!PrevPartial) 3845 ClassTemplate->AddPartialSpecialization(Partial, InsertPos); 3846 Specialization = Partial; 3847 3848 // If we are providing an explicit specialization of a member class 3849 // template specialization, make a note of that. 3850 if (PrevPartial && PrevPartial->getInstantiatedFromMember()) 3851 PrevPartial->setMemberSpecialization(); 3852 3853 // Check that all of the template parameters of the class template 3854 // partial specialization are deducible from the template 3855 // arguments. If not, this class template partial specialization 3856 // will never be used. 3857 llvm::SmallVector<bool, 8> DeducibleParams; 3858 DeducibleParams.resize(TemplateParams->size()); 3859 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true, 3860 TemplateParams->getDepth(), 3861 DeducibleParams); 3862 unsigned NumNonDeducible = 0; 3863 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) 3864 if (!DeducibleParams[I]) 3865 ++NumNonDeducible; 3866 3867 if (NumNonDeducible) { 3868 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible) 3869 << (NumNonDeducible > 1) 3870 << SourceRange(TemplateNameLoc, RAngleLoc); 3871 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) { 3872 if (!DeducibleParams[I]) { 3873 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I)); 3874 if (Param->getDeclName()) 3875 Diag(Param->getLocation(), 3876 diag::note_partial_spec_unused_parameter) 3877 << Param->getDeclName(); 3878 else 3879 Diag(Param->getLocation(), 3880 diag::note_partial_spec_unused_parameter) 3881 << "<anonymous>"; 3882 } 3883 } 3884 } 3885 } else { 3886 // Create a new class template specialization declaration node for 3887 // this explicit specialization or friend declaration. 3888 Specialization 3889 = ClassTemplateSpecializationDecl::Create(Context, Kind, 3890 ClassTemplate->getDeclContext(), 3891 TemplateNameLoc, 3892 ClassTemplate, 3893 Converted, 3894 PrevDecl); 3895 SetNestedNameSpecifier(Specialization, SS); 3896 if (NumMatchedTemplateParamLists > 0 && SS.isSet()) { 3897 Specialization->setTemplateParameterListsInfo(Context, 3898 NumMatchedTemplateParamLists, 3899 (TemplateParameterList**) TemplateParameterLists.release()); 3900 } 3901 3902 if (!PrevDecl) 3903 ClassTemplate->AddSpecialization(Specialization, InsertPos); 3904 3905 CanonType = Context.getTypeDeclType(Specialization); 3906 } 3907 3908 // C++ [temp.expl.spec]p6: 3909 // If a template, a member template or the member of a class template is 3910 // explicitly specialized then that specialization shall be declared 3911 // before the first use of that specialization that would cause an implicit 3912 // instantiation to take place, in every translation unit in which such a 3913 // use occurs; no diagnostic is required. 3914 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { 3915 bool Okay = false; 3916 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 3917 // Is there any previous explicit specialization declaration? 3918 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) { 3919 Okay = true; 3920 break; 3921 } 3922 } 3923 3924 if (!Okay) { 3925 SourceRange Range(TemplateNameLoc, RAngleLoc); 3926 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) 3927 << Context.getTypeDeclType(Specialization) << Range; 3928 3929 Diag(PrevDecl->getPointOfInstantiation(), 3930 diag::note_instantiation_required_here) 3931 << (PrevDecl->getTemplateSpecializationKind() 3932 != TSK_ImplicitInstantiation); 3933 return true; 3934 } 3935 } 3936 3937 // If this is not a friend, note that this is an explicit specialization. 3938 if (TUK != TUK_Friend) 3939 Specialization->setSpecializationKind(TSK_ExplicitSpecialization); 3940 3941 // Check that this isn't a redefinition of this specialization. 3942 if (TUK == TUK_Definition) { 3943 if (RecordDecl *Def = Specialization->getDefinition()) { 3944 SourceRange Range(TemplateNameLoc, RAngleLoc); 3945 Diag(TemplateNameLoc, diag::err_redefinition) 3946 << Context.getTypeDeclType(Specialization) << Range; 3947 Diag(Def->getLocation(), diag::note_previous_definition); 3948 Specialization->setInvalidDecl(); 3949 return true; 3950 } 3951 } 3952 3953 // Build the fully-sugared type for this class template 3954 // specialization as the user wrote in the specialization 3955 // itself. This means that we'll pretty-print the type retrieved 3956 // from the specialization's declaration the way that the user 3957 // actually wrote the specialization, rather than formatting the 3958 // name based on the "canonical" representation used to store the 3959 // template arguments in the specialization. 3960 TypeSourceInfo *WrittenTy 3961 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 3962 TemplateArgs, CanonType); 3963 if (TUK != TUK_Friend) { 3964 Specialization->setTypeAsWritten(WrittenTy); 3965 if (TemplateParams) 3966 Specialization->setTemplateKeywordLoc(TemplateParams->getTemplateLoc()); 3967 } 3968 TemplateArgsIn.release(); 3969 3970 // C++ [temp.expl.spec]p9: 3971 // A template explicit specialization is in the scope of the 3972 // namespace in which the template was defined. 3973 // 3974 // We actually implement this paragraph where we set the semantic 3975 // context (in the creation of the ClassTemplateSpecializationDecl), 3976 // but we also maintain the lexical context where the actual 3977 // definition occurs. 3978 Specialization->setLexicalDeclContext(CurContext); 3979 3980 // We may be starting the definition of this specialization. 3981 if (TUK == TUK_Definition) 3982 Specialization->startDefinition(); 3983 3984 if (TUK == TUK_Friend) { 3985 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 3986 TemplateNameLoc, 3987 WrittenTy, 3988 /*FIXME:*/KWLoc); 3989 Friend->setAccess(AS_public); 3990 CurContext->addDecl(Friend); 3991 } else { 3992 // Add the specialization into its lexical context, so that it can 3993 // be seen when iterating through the list of declarations in that 3994 // context. However, specializations are not found by name lookup. 3995 CurContext->addDecl(Specialization); 3996 } 3997 return Specialization; 3998} 3999 4000Decl *Sema::ActOnTemplateDeclarator(Scope *S, 4001 MultiTemplateParamsArg TemplateParameterLists, 4002 Declarator &D) { 4003 return HandleDeclarator(S, D, move(TemplateParameterLists), false); 4004} 4005 4006Decl *Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, 4007 MultiTemplateParamsArg TemplateParameterLists, 4008 Declarator &D) { 4009 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4010 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4011 "Not a function declarator!"); 4012 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4013 4014 if (FTI.hasPrototype) { 4015 // FIXME: Diagnose arguments without names in C. 4016 } 4017 4018 Scope *ParentScope = FnBodyScope->getParent(); 4019 4020 Decl *DP = HandleDeclarator(ParentScope, D, 4021 move(TemplateParameterLists), 4022 /*IsFunctionDefinition=*/true); 4023 if (FunctionTemplateDecl *FunctionTemplate 4024 = dyn_cast_or_null<FunctionTemplateDecl>(DP)) 4025 return ActOnStartOfFunctionDef(FnBodyScope, 4026 FunctionTemplate->getTemplatedDecl()); 4027 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP)) 4028 return ActOnStartOfFunctionDef(FnBodyScope, Function); 4029 return 0; 4030} 4031 4032/// \brief Strips various properties off an implicit instantiation 4033/// that has just been explicitly specialized. 4034static void StripImplicitInstantiation(NamedDecl *D) { 4035 D->dropAttrs(); 4036 4037 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 4038 FD->setInlineSpecified(false); 4039 } 4040} 4041 4042/// \brief Diagnose cases where we have an explicit template specialization 4043/// before/after an explicit template instantiation, producing diagnostics 4044/// for those cases where they are required and determining whether the 4045/// new specialization/instantiation will have any effect. 4046/// 4047/// \param NewLoc the location of the new explicit specialization or 4048/// instantiation. 4049/// 4050/// \param NewTSK the kind of the new explicit specialization or instantiation. 4051/// 4052/// \param PrevDecl the previous declaration of the entity. 4053/// 4054/// \param PrevTSK the kind of the old explicit specialization or instantiatin. 4055/// 4056/// \param PrevPointOfInstantiation if valid, indicates where the previus 4057/// declaration was instantiated (either implicitly or explicitly). 4058/// 4059/// \param HasNoEffect will be set to true to indicate that the new 4060/// specialization or instantiation has no effect and should be ignored. 4061/// 4062/// \returns true if there was an error that should prevent the introduction of 4063/// the new declaration into the AST, false otherwise. 4064bool 4065Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, 4066 TemplateSpecializationKind NewTSK, 4067 NamedDecl *PrevDecl, 4068 TemplateSpecializationKind PrevTSK, 4069 SourceLocation PrevPointOfInstantiation, 4070 bool &HasNoEffect) { 4071 HasNoEffect = false; 4072 4073 switch (NewTSK) { 4074 case TSK_Undeclared: 4075 case TSK_ImplicitInstantiation: 4076 assert(false && "Don't check implicit instantiations here"); 4077 return false; 4078 4079 case TSK_ExplicitSpecialization: 4080 switch (PrevTSK) { 4081 case TSK_Undeclared: 4082 case TSK_ExplicitSpecialization: 4083 // Okay, we're just specializing something that is either already 4084 // explicitly specialized or has merely been mentioned without any 4085 // instantiation. 4086 return false; 4087 4088 case TSK_ImplicitInstantiation: 4089 if (PrevPointOfInstantiation.isInvalid()) { 4090 // The declaration itself has not actually been instantiated, so it is 4091 // still okay to specialize it. 4092 StripImplicitInstantiation(PrevDecl); 4093 return false; 4094 } 4095 // Fall through 4096 4097 case TSK_ExplicitInstantiationDeclaration: 4098 case TSK_ExplicitInstantiationDefinition: 4099 assert((PrevTSK == TSK_ImplicitInstantiation || 4100 PrevPointOfInstantiation.isValid()) && 4101 "Explicit instantiation without point of instantiation?"); 4102 4103 // C++ [temp.expl.spec]p6: 4104 // If a template, a member template or the member of a class template 4105 // is explicitly specialized then that specialization shall be declared 4106 // before the first use of that specialization that would cause an 4107 // implicit instantiation to take place, in every translation unit in 4108 // which such a use occurs; no diagnostic is required. 4109 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 4110 // Is there any previous explicit specialization declaration? 4111 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) 4112 return false; 4113 } 4114 4115 Diag(NewLoc, diag::err_specialization_after_instantiation) 4116 << PrevDecl; 4117 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) 4118 << (PrevTSK != TSK_ImplicitInstantiation); 4119 4120 return true; 4121 } 4122 break; 4123 4124 case TSK_ExplicitInstantiationDeclaration: 4125 switch (PrevTSK) { 4126 case TSK_ExplicitInstantiationDeclaration: 4127 // This explicit instantiation declaration is redundant (that's okay). 4128 HasNoEffect = true; 4129 return false; 4130 4131 case TSK_Undeclared: 4132 case TSK_ImplicitInstantiation: 4133 // We're explicitly instantiating something that may have already been 4134 // implicitly instantiated; that's fine. 4135 return false; 4136 4137 case TSK_ExplicitSpecialization: 4138 // C++0x [temp.explicit]p4: 4139 // For a given set of template parameters, if an explicit instantiation 4140 // of a template appears after a declaration of an explicit 4141 // specialization for that template, the explicit instantiation has no 4142 // effect. 4143 HasNoEffect = true; 4144 return false; 4145 4146 case TSK_ExplicitInstantiationDefinition: 4147 // C++0x [temp.explicit]p10: 4148 // If an entity is the subject of both an explicit instantiation 4149 // declaration and an explicit instantiation definition in the same 4150 // translation unit, the definition shall follow the declaration. 4151 Diag(NewLoc, 4152 diag::err_explicit_instantiation_declaration_after_definition); 4153 Diag(PrevPointOfInstantiation, 4154 diag::note_explicit_instantiation_definition_here); 4155 assert(PrevPointOfInstantiation.isValid() && 4156 "Explicit instantiation without point of instantiation?"); 4157 HasNoEffect = true; 4158 return false; 4159 } 4160 break; 4161 4162 case TSK_ExplicitInstantiationDefinition: 4163 switch (PrevTSK) { 4164 case TSK_Undeclared: 4165 case TSK_ImplicitInstantiation: 4166 // We're explicitly instantiating something that may have already been 4167 // implicitly instantiated; that's fine. 4168 return false; 4169 4170 case TSK_ExplicitSpecialization: 4171 // C++ DR 259, C++0x [temp.explicit]p4: 4172 // For a given set of template parameters, if an explicit 4173 // instantiation of a template appears after a declaration of 4174 // an explicit specialization for that template, the explicit 4175 // instantiation has no effect. 4176 // 4177 // In C++98/03 mode, we only give an extension warning here, because it 4178 // is not harmful to try to explicitly instantiate something that 4179 // has been explicitly specialized. 4180 if (!getLangOptions().CPlusPlus0x) { 4181 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization) 4182 << PrevDecl; 4183 Diag(PrevDecl->getLocation(), 4184 diag::note_previous_template_specialization); 4185 } 4186 HasNoEffect = true; 4187 return false; 4188 4189 case TSK_ExplicitInstantiationDeclaration: 4190 // We're explicity instantiating a definition for something for which we 4191 // were previously asked to suppress instantiations. That's fine. 4192 return false; 4193 4194 case TSK_ExplicitInstantiationDefinition: 4195 // C++0x [temp.spec]p5: 4196 // For a given template and a given set of template-arguments, 4197 // - an explicit instantiation definition shall appear at most once 4198 // in a program, 4199 Diag(NewLoc, diag::err_explicit_instantiation_duplicate) 4200 << PrevDecl; 4201 Diag(PrevPointOfInstantiation, 4202 diag::note_previous_explicit_instantiation); 4203 HasNoEffect = true; 4204 return false; 4205 } 4206 break; 4207 } 4208 4209 assert(false && "Missing specialization/instantiation case?"); 4210 4211 return false; 4212} 4213 4214/// \brief Perform semantic analysis for the given dependent function 4215/// template specialization. The only possible way to get a dependent 4216/// function template specialization is with a friend declaration, 4217/// like so: 4218/// 4219/// template <class T> void foo(T); 4220/// template <class T> class A { 4221/// friend void foo<>(T); 4222/// }; 4223/// 4224/// There really isn't any useful analysis we can do here, so we 4225/// just store the information. 4226bool 4227Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD, 4228 const TemplateArgumentListInfo &ExplicitTemplateArgs, 4229 LookupResult &Previous) { 4230 // Remove anything from Previous that isn't a function template in 4231 // the correct context. 4232 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 4233 LookupResult::Filter F = Previous.makeFilter(); 4234 while (F.hasNext()) { 4235 NamedDecl *D = F.next()->getUnderlyingDecl(); 4236 if (!isa<FunctionTemplateDecl>(D) || 4237 !FDLookupContext->Equals(D->getDeclContext()->getLookupContext())) 4238 F.erase(); 4239 } 4240 F.done(); 4241 4242 // Should this be diagnosed here? 4243 if (Previous.empty()) return true; 4244 4245 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(), 4246 ExplicitTemplateArgs); 4247 return false; 4248} 4249 4250/// \brief Perform semantic analysis for the given function template 4251/// specialization. 4252/// 4253/// This routine performs all of the semantic analysis required for an 4254/// explicit function template specialization. On successful completion, 4255/// the function declaration \p FD will become a function template 4256/// specialization. 4257/// 4258/// \param FD the function declaration, which will be updated to become a 4259/// function template specialization. 4260/// 4261/// \param ExplicitTemplateArgs the explicitly-provided template arguments, 4262/// if any. Note that this may be valid info even when 0 arguments are 4263/// explicitly provided as in, e.g., \c void sort<>(char*, char*); 4264/// as it anyway contains info on the angle brackets locations. 4265/// 4266/// \param PrevDecl the set of declarations that may be specialized by 4267/// this function specialization. 4268bool 4269Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, 4270 const TemplateArgumentListInfo *ExplicitTemplateArgs, 4271 LookupResult &Previous) { 4272 // The set of function template specializations that could match this 4273 // explicit function template specialization. 4274 UnresolvedSet<8> Candidates; 4275 4276 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 4277 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4278 I != E; ++I) { 4279 NamedDecl *Ovl = (*I)->getUnderlyingDecl(); 4280 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { 4281 // Only consider templates found within the same semantic lookup scope as 4282 // FD. 4283 if (!FDLookupContext->Equals(Ovl->getDeclContext()->getLookupContext())) 4284 continue; 4285 4286 // C++ [temp.expl.spec]p11: 4287 // A trailing template-argument can be left unspecified in the 4288 // template-id naming an explicit function template specialization 4289 // provided it can be deduced from the function argument type. 4290 // Perform template argument deduction to determine whether we may be 4291 // specializing this template. 4292 // FIXME: It is somewhat wasteful to build 4293 TemplateDeductionInfo Info(Context, FD->getLocation()); 4294 FunctionDecl *Specialization = 0; 4295 if (TemplateDeductionResult TDK 4296 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, 4297 FD->getType(), 4298 Specialization, 4299 Info)) { 4300 // FIXME: Template argument deduction failed; record why it failed, so 4301 // that we can provide nifty diagnostics. 4302 (void)TDK; 4303 continue; 4304 } 4305 4306 // Record this candidate. 4307 Candidates.addDecl(Specialization, I.getAccess()); 4308 } 4309 } 4310 4311 // Find the most specialized function template. 4312 UnresolvedSetIterator Result 4313 = getMostSpecialized(Candidates.begin(), Candidates.end(), 4314 TPOC_Other, FD->getLocation(), 4315 PDiag(diag::err_function_template_spec_no_match) 4316 << FD->getDeclName(), 4317 PDiag(diag::err_function_template_spec_ambiguous) 4318 << FD->getDeclName() << (ExplicitTemplateArgs != 0), 4319 PDiag(diag::note_function_template_spec_matched)); 4320 if (Result == Candidates.end()) 4321 return true; 4322 4323 // Ignore access information; it doesn't figure into redeclaration checking. 4324 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 4325 Specialization->setLocation(FD->getLocation()); 4326 4327 // FIXME: Check if the prior specialization has a point of instantiation. 4328 // If so, we have run afoul of . 4329 4330 // If this is a friend declaration, then we're not really declaring 4331 // an explicit specialization. 4332 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None); 4333 4334 // Check the scope of this explicit specialization. 4335 if (!isFriend && 4336 CheckTemplateSpecializationScope(*this, 4337 Specialization->getPrimaryTemplate(), 4338 Specialization, FD->getLocation(), 4339 false)) 4340 return true; 4341 4342 // C++ [temp.expl.spec]p6: 4343 // If a template, a member template or the member of a class template is 4344 // explicitly specialized then that specialization shall be declared 4345 // before the first use of that specialization that would cause an implicit 4346 // instantiation to take place, in every translation unit in which such a 4347 // use occurs; no diagnostic is required. 4348 FunctionTemplateSpecializationInfo *SpecInfo 4349 = Specialization->getTemplateSpecializationInfo(); 4350 assert(SpecInfo && "Function template specialization info missing?"); 4351 4352 bool HasNoEffect = false; 4353 if (!isFriend && 4354 CheckSpecializationInstantiationRedecl(FD->getLocation(), 4355 TSK_ExplicitSpecialization, 4356 Specialization, 4357 SpecInfo->getTemplateSpecializationKind(), 4358 SpecInfo->getPointOfInstantiation(), 4359 HasNoEffect)) 4360 return true; 4361 4362 // Mark the prior declaration as an explicit specialization, so that later 4363 // clients know that this is an explicit specialization. 4364 if (!isFriend) { 4365 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); 4366 MarkUnusedFileScopedDecl(Specialization); 4367 } 4368 4369 // Turn the given function declaration into a function template 4370 // specialization, with the template arguments from the previous 4371 // specialization. 4372 // Take copies of (semantic and syntactic) template argument lists. 4373 const TemplateArgumentList* TemplArgs = new (Context) 4374 TemplateArgumentList(Specialization->getTemplateSpecializationArgs()); 4375 const TemplateArgumentListInfo* TemplArgsAsWritten = ExplicitTemplateArgs 4376 ? new (Context) TemplateArgumentListInfo(*ExplicitTemplateArgs) : 0; 4377 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(), 4378 TemplArgs, /*InsertPos=*/0, 4379 SpecInfo->getTemplateSpecializationKind(), 4380 TemplArgsAsWritten); 4381 4382 // The "previous declaration" for this function template specialization is 4383 // the prior function template specialization. 4384 Previous.clear(); 4385 Previous.addDecl(Specialization); 4386 return false; 4387} 4388 4389/// \brief Perform semantic analysis for the given non-template member 4390/// specialization. 4391/// 4392/// This routine performs all of the semantic analysis required for an 4393/// explicit member function specialization. On successful completion, 4394/// the function declaration \p FD will become a member function 4395/// specialization. 4396/// 4397/// \param Member the member declaration, which will be updated to become a 4398/// specialization. 4399/// 4400/// \param Previous the set of declarations, one of which may be specialized 4401/// by this function specialization; the set will be modified to contain the 4402/// redeclared member. 4403bool 4404Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { 4405 assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); 4406 4407 // Try to find the member we are instantiating. 4408 NamedDecl *Instantiation = 0; 4409 NamedDecl *InstantiatedFrom = 0; 4410 MemberSpecializationInfo *MSInfo = 0; 4411 4412 if (Previous.empty()) { 4413 // Nowhere to look anyway. 4414 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { 4415 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4416 I != E; ++I) { 4417 NamedDecl *D = (*I)->getUnderlyingDecl(); 4418 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 4419 if (Context.hasSameType(Function->getType(), Method->getType())) { 4420 Instantiation = Method; 4421 InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); 4422 MSInfo = Method->getMemberSpecializationInfo(); 4423 break; 4424 } 4425 } 4426 } 4427 } else if (isa<VarDecl>(Member)) { 4428 VarDecl *PrevVar; 4429 if (Previous.isSingleResult() && 4430 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) 4431 if (PrevVar->isStaticDataMember()) { 4432 Instantiation = PrevVar; 4433 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); 4434 MSInfo = PrevVar->getMemberSpecializationInfo(); 4435 } 4436 } else if (isa<RecordDecl>(Member)) { 4437 CXXRecordDecl *PrevRecord; 4438 if (Previous.isSingleResult() && 4439 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { 4440 Instantiation = PrevRecord; 4441 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); 4442 MSInfo = PrevRecord->getMemberSpecializationInfo(); 4443 } 4444 } 4445 4446 if (!Instantiation) { 4447 // There is no previous declaration that matches. Since member 4448 // specializations are always out-of-line, the caller will complain about 4449 // this mismatch later. 4450 return false; 4451 } 4452 4453 // If this is a friend, just bail out here before we start turning 4454 // things into explicit specializations. 4455 if (Member->getFriendObjectKind() != Decl::FOK_None) { 4456 // Preserve instantiation information. 4457 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) { 4458 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction( 4459 cast<CXXMethodDecl>(InstantiatedFrom), 4460 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind()); 4461 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) { 4462 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4463 cast<CXXRecordDecl>(InstantiatedFrom), 4464 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind()); 4465 } 4466 4467 Previous.clear(); 4468 Previous.addDecl(Instantiation); 4469 return false; 4470 } 4471 4472 // Make sure that this is a specialization of a member. 4473 if (!InstantiatedFrom) { 4474 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) 4475 << Member; 4476 Diag(Instantiation->getLocation(), diag::note_specialized_decl); 4477 return true; 4478 } 4479 4480 // C++ [temp.expl.spec]p6: 4481 // If a template, a member template or the member of a class template is 4482 // explicitly specialized then that spe- cialization shall be declared 4483 // before the first use of that specialization that would cause an implicit 4484 // instantiation to take place, in every translation unit in which such a 4485 // use occurs; no diagnostic is required. 4486 assert(MSInfo && "Member specialization info missing?"); 4487 4488 bool HasNoEffect = false; 4489 if (CheckSpecializationInstantiationRedecl(Member->getLocation(), 4490 TSK_ExplicitSpecialization, 4491 Instantiation, 4492 MSInfo->getTemplateSpecializationKind(), 4493 MSInfo->getPointOfInstantiation(), 4494 HasNoEffect)) 4495 return true; 4496 4497 // Check the scope of this explicit specialization. 4498 if (CheckTemplateSpecializationScope(*this, 4499 InstantiatedFrom, 4500 Instantiation, Member->getLocation(), 4501 false)) 4502 return true; 4503 4504 // Note that this is an explicit instantiation of a member. 4505 // the original declaration to note that it is an explicit specialization 4506 // (if it was previously an implicit instantiation). This latter step 4507 // makes bookkeeping easier. 4508 if (isa<FunctionDecl>(Member)) { 4509 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); 4510 if (InstantiationFunction->getTemplateSpecializationKind() == 4511 TSK_ImplicitInstantiation) { 4512 InstantiationFunction->setTemplateSpecializationKind( 4513 TSK_ExplicitSpecialization); 4514 InstantiationFunction->setLocation(Member->getLocation()); 4515 } 4516 4517 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( 4518 cast<CXXMethodDecl>(InstantiatedFrom), 4519 TSK_ExplicitSpecialization); 4520 MarkUnusedFileScopedDecl(InstantiationFunction); 4521 } else if (isa<VarDecl>(Member)) { 4522 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); 4523 if (InstantiationVar->getTemplateSpecializationKind() == 4524 TSK_ImplicitInstantiation) { 4525 InstantiationVar->setTemplateSpecializationKind( 4526 TSK_ExplicitSpecialization); 4527 InstantiationVar->setLocation(Member->getLocation()); 4528 } 4529 4530 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), 4531 cast<VarDecl>(InstantiatedFrom), 4532 TSK_ExplicitSpecialization); 4533 MarkUnusedFileScopedDecl(InstantiationVar); 4534 } else { 4535 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain"); 4536 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); 4537 if (InstantiationClass->getTemplateSpecializationKind() == 4538 TSK_ImplicitInstantiation) { 4539 InstantiationClass->setTemplateSpecializationKind( 4540 TSK_ExplicitSpecialization); 4541 InstantiationClass->setLocation(Member->getLocation()); 4542 } 4543 4544 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4545 cast<CXXRecordDecl>(InstantiatedFrom), 4546 TSK_ExplicitSpecialization); 4547 } 4548 4549 // Save the caller the trouble of having to figure out which declaration 4550 // this specialization matches. 4551 Previous.clear(); 4552 Previous.addDecl(Instantiation); 4553 return false; 4554} 4555 4556/// \brief Check the scope of an explicit instantiation. 4557/// 4558/// \returns true if a serious error occurs, false otherwise. 4559static bool CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, 4560 SourceLocation InstLoc, 4561 bool WasQualifiedName) { 4562 DeclContext *ExpectedContext 4563 = D->getDeclContext()->getEnclosingNamespaceContext()->getLookupContext(); 4564 DeclContext *CurContext = S.CurContext->getLookupContext(); 4565 4566 if (CurContext->isRecord()) { 4567 S.Diag(InstLoc, diag::err_explicit_instantiation_in_class) 4568 << D; 4569 return true; 4570 } 4571 4572 // C++0x [temp.explicit]p2: 4573 // An explicit instantiation shall appear in an enclosing namespace of its 4574 // template. 4575 // 4576 // This is DR275, which we do not retroactively apply to C++98/03. 4577 if (S.getLangOptions().CPlusPlus0x && 4578 !CurContext->Encloses(ExpectedContext)) { 4579 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(ExpectedContext)) 4580 S.Diag(InstLoc, 4581 S.getLangOptions().CPlusPlus0x? 4582 diag::err_explicit_instantiation_out_of_scope 4583 : diag::warn_explicit_instantiation_out_of_scope_0x) 4584 << D << NS; 4585 else 4586 S.Diag(InstLoc, 4587 S.getLangOptions().CPlusPlus0x? 4588 diag::err_explicit_instantiation_must_be_global 4589 : diag::warn_explicit_instantiation_out_of_scope_0x) 4590 << D; 4591 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4592 return false; 4593 } 4594 4595 // C++0x [temp.explicit]p2: 4596 // If the name declared in the explicit instantiation is an unqualified 4597 // name, the explicit instantiation shall appear in the namespace where 4598 // its template is declared or, if that namespace is inline (7.3.1), any 4599 // namespace from its enclosing namespace set. 4600 if (WasQualifiedName) 4601 return false; 4602 4603 if (CurContext->Equals(ExpectedContext)) 4604 return false; 4605 4606 S.Diag(InstLoc, 4607 S.getLangOptions().CPlusPlus0x? 4608 diag::err_explicit_instantiation_unqualified_wrong_namespace 4609 : diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x) 4610 << D << ExpectedContext; 4611 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4612 return false; 4613} 4614 4615/// \brief Determine whether the given scope specifier has a template-id in it. 4616static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { 4617 if (!SS.isSet()) 4618 return false; 4619 4620 // C++0x [temp.explicit]p2: 4621 // If the explicit instantiation is for a member function, a member class 4622 // or a static data member of a class template specialization, the name of 4623 // the class template specialization in the qualified-id for the member 4624 // name shall be a simple-template-id. 4625 // 4626 // C++98 has the same restriction, just worded differently. 4627 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 4628 NNS; NNS = NNS->getPrefix()) 4629 if (Type *T = NNS->getAsType()) 4630 if (isa<TemplateSpecializationType>(T)) 4631 return true; 4632 4633 return false; 4634} 4635 4636// Explicit instantiation of a class template specialization 4637Sema::DeclResult 4638Sema::ActOnExplicitInstantiation(Scope *S, 4639 SourceLocation ExternLoc, 4640 SourceLocation TemplateLoc, 4641 unsigned TagSpec, 4642 SourceLocation KWLoc, 4643 const CXXScopeSpec &SS, 4644 TemplateTy TemplateD, 4645 SourceLocation TemplateNameLoc, 4646 SourceLocation LAngleLoc, 4647 ASTTemplateArgsPtr TemplateArgsIn, 4648 SourceLocation RAngleLoc, 4649 AttributeList *Attr) { 4650 // Find the class template we're specializing 4651 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 4652 ClassTemplateDecl *ClassTemplate 4653 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); 4654 4655 // Check that the specialization uses the same tag kind as the 4656 // original template. 4657 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 4658 assert(Kind != TTK_Enum && 4659 "Invalid enum tag in class template explicit instantiation!"); 4660 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 4661 Kind, KWLoc, 4662 *ClassTemplate->getIdentifier())) { 4663 Diag(KWLoc, diag::err_use_with_wrong_tag) 4664 << ClassTemplate 4665 << FixItHint::CreateReplacement(KWLoc, 4666 ClassTemplate->getTemplatedDecl()->getKindName()); 4667 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 4668 diag::note_previous_use); 4669 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 4670 } 4671 4672 // C++0x [temp.explicit]p2: 4673 // There are two forms of explicit instantiation: an explicit instantiation 4674 // definition and an explicit instantiation declaration. An explicit 4675 // instantiation declaration begins with the extern keyword. [...] 4676 TemplateSpecializationKind TSK 4677 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4678 : TSK_ExplicitInstantiationDeclaration; 4679 4680 // Translate the parser's template argument list in our AST format. 4681 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 4682 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 4683 4684 // Check that the template argument list is well-formed for this 4685 // template. 4686 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 4687 TemplateArgs.size()); 4688 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 4689 TemplateArgs, false, Converted)) 4690 return true; 4691 4692 assert((Converted.structuredSize() == 4693 ClassTemplate->getTemplateParameters()->size()) && 4694 "Converted template argument list is too short!"); 4695 4696 // Find the class template specialization declaration that 4697 // corresponds to these arguments. 4698 void *InsertPos = 0; 4699 ClassTemplateSpecializationDecl *PrevDecl 4700 = ClassTemplate->findSpecialization(Converted.getFlatArguments(), 4701 Converted.flatSize(), InsertPos); 4702 4703 TemplateSpecializationKind PrevDecl_TSK 4704 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared; 4705 4706 // C++0x [temp.explicit]p2: 4707 // [...] An explicit instantiation shall appear in an enclosing 4708 // namespace of its template. [...] 4709 // 4710 // This is C++ DR 275. 4711 if (CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, 4712 SS.isSet())) 4713 return true; 4714 4715 ClassTemplateSpecializationDecl *Specialization = 0; 4716 4717 bool ReusedDecl = false; 4718 bool HasNoEffect = false; 4719 if (PrevDecl) { 4720 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, 4721 PrevDecl, PrevDecl_TSK, 4722 PrevDecl->getPointOfInstantiation(), 4723 HasNoEffect)) 4724 return PrevDecl; 4725 4726 // Even though HasNoEffect == true means that this explicit instantiation 4727 // has no effect on semantics, we go on to put its syntax in the AST. 4728 4729 if (PrevDecl_TSK == TSK_ImplicitInstantiation || 4730 PrevDecl_TSK == TSK_Undeclared) { 4731 // Since the only prior class template specialization with these 4732 // arguments was referenced but not declared, reuse that 4733 // declaration node as our own, updating the source location 4734 // for the template name to reflect our new declaration. 4735 // (Other source locations will be updated later.) 4736 Specialization = PrevDecl; 4737 Specialization->setLocation(TemplateNameLoc); 4738 PrevDecl = 0; 4739 ReusedDecl = true; 4740 } 4741 } 4742 4743 if (!Specialization) { 4744 // Create a new class template specialization declaration node for 4745 // this explicit specialization. 4746 Specialization 4747 = ClassTemplateSpecializationDecl::Create(Context, Kind, 4748 ClassTemplate->getDeclContext(), 4749 TemplateNameLoc, 4750 ClassTemplate, 4751 Converted, PrevDecl); 4752 SetNestedNameSpecifier(Specialization, SS); 4753 4754 if (!HasNoEffect && !PrevDecl) { 4755 // Insert the new specialization. 4756 ClassTemplate->AddSpecialization(Specialization, InsertPos); 4757 } 4758 } 4759 4760 // Build the fully-sugared type for this explicit instantiation as 4761 // the user wrote in the explicit instantiation itself. This means 4762 // that we'll pretty-print the type retrieved from the 4763 // specialization's declaration the way that the user actually wrote 4764 // the explicit instantiation, rather than formatting the name based 4765 // on the "canonical" representation used to store the template 4766 // arguments in the specialization. 4767 TypeSourceInfo *WrittenTy 4768 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 4769 TemplateArgs, 4770 Context.getTypeDeclType(Specialization)); 4771 Specialization->setTypeAsWritten(WrittenTy); 4772 TemplateArgsIn.release(); 4773 4774 // Set source locations for keywords. 4775 Specialization->setExternLoc(ExternLoc); 4776 Specialization->setTemplateKeywordLoc(TemplateLoc); 4777 4778 // Add the explicit instantiation into its lexical context. However, 4779 // since explicit instantiations are never found by name lookup, we 4780 // just put it into the declaration context directly. 4781 Specialization->setLexicalDeclContext(CurContext); 4782 CurContext->addDecl(Specialization); 4783 4784 // Syntax is now OK, so return if it has no other effect on semantics. 4785 if (HasNoEffect) { 4786 // Set the template specialization kind. 4787 Specialization->setTemplateSpecializationKind(TSK); 4788 return Specialization; 4789 } 4790 4791 // C++ [temp.explicit]p3: 4792 // A definition of a class template or class member template 4793 // shall be in scope at the point of the explicit instantiation of 4794 // the class template or class member template. 4795 // 4796 // This check comes when we actually try to perform the 4797 // instantiation. 4798 ClassTemplateSpecializationDecl *Def 4799 = cast_or_null<ClassTemplateSpecializationDecl>( 4800 Specialization->getDefinition()); 4801 if (!Def) 4802 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); 4803 else if (TSK == TSK_ExplicitInstantiationDefinition) { 4804 MarkVTableUsed(TemplateNameLoc, Specialization, true); 4805 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation()); 4806 } 4807 4808 // Instantiate the members of this class template specialization. 4809 Def = cast_or_null<ClassTemplateSpecializationDecl>( 4810 Specialization->getDefinition()); 4811 if (Def) { 4812 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind(); 4813 4814 // Fix a TSK_ExplicitInstantiationDeclaration followed by a 4815 // TSK_ExplicitInstantiationDefinition 4816 if (Old_TSK == TSK_ExplicitInstantiationDeclaration && 4817 TSK == TSK_ExplicitInstantiationDefinition) 4818 Def->setTemplateSpecializationKind(TSK); 4819 4820 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); 4821 } 4822 4823 // Set the template specialization kind. 4824 Specialization->setTemplateSpecializationKind(TSK); 4825 return Specialization; 4826} 4827 4828// Explicit instantiation of a member class of a class template. 4829DeclResult 4830Sema::ActOnExplicitInstantiation(Scope *S, 4831 SourceLocation ExternLoc, 4832 SourceLocation TemplateLoc, 4833 unsigned TagSpec, 4834 SourceLocation KWLoc, 4835 CXXScopeSpec &SS, 4836 IdentifierInfo *Name, 4837 SourceLocation NameLoc, 4838 AttributeList *Attr) { 4839 4840 bool Owned = false; 4841 bool IsDependent = false; 4842 Decl *TagD = ActOnTag(S, TagSpec, Action::TUK_Reference, 4843 KWLoc, SS, Name, NameLoc, Attr, AS_none, 4844 MultiTemplateParamsArg(*this, 0, 0), 4845 Owned, IsDependent); 4846 assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); 4847 4848 if (!TagD) 4849 return true; 4850 4851 TagDecl *Tag = cast<TagDecl>(TagD); 4852 if (Tag->isEnum()) { 4853 Diag(TemplateLoc, diag::err_explicit_instantiation_enum) 4854 << Context.getTypeDeclType(Tag); 4855 return true; 4856 } 4857 4858 if (Tag->isInvalidDecl()) 4859 return true; 4860 4861 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); 4862 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); 4863 if (!Pattern) { 4864 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) 4865 << Context.getTypeDeclType(Record); 4866 Diag(Record->getLocation(), diag::note_nontemplate_decl_here); 4867 return true; 4868 } 4869 4870 // C++0x [temp.explicit]p2: 4871 // If the explicit instantiation is for a class or member class, the 4872 // elaborated-type-specifier in the declaration shall include a 4873 // simple-template-id. 4874 // 4875 // C++98 has the same restriction, just worded differently. 4876 if (!ScopeSpecifierHasTemplateId(SS)) 4877 Diag(TemplateLoc, diag::ext_explicit_instantiation_without_qualified_id) 4878 << Record << SS.getRange(); 4879 4880 // C++0x [temp.explicit]p2: 4881 // There are two forms of explicit instantiation: an explicit instantiation 4882 // definition and an explicit instantiation declaration. An explicit 4883 // instantiation declaration begins with the extern keyword. [...] 4884 TemplateSpecializationKind TSK 4885 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4886 : TSK_ExplicitInstantiationDeclaration; 4887 4888 // C++0x [temp.explicit]p2: 4889 // [...] An explicit instantiation shall appear in an enclosing 4890 // namespace of its template. [...] 4891 // 4892 // This is C++ DR 275. 4893 CheckExplicitInstantiationScope(*this, Record, NameLoc, true); 4894 4895 // Verify that it is okay to explicitly instantiate here. 4896 CXXRecordDecl *PrevDecl 4897 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration()); 4898 if (!PrevDecl && Record->getDefinition()) 4899 PrevDecl = Record; 4900 if (PrevDecl) { 4901 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); 4902 bool HasNoEffect = false; 4903 assert(MSInfo && "No member specialization information?"); 4904 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, 4905 PrevDecl, 4906 MSInfo->getTemplateSpecializationKind(), 4907 MSInfo->getPointOfInstantiation(), 4908 HasNoEffect)) 4909 return true; 4910 if (HasNoEffect) 4911 return TagD; 4912 } 4913 4914 CXXRecordDecl *RecordDef 4915 = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4916 if (!RecordDef) { 4917 // C++ [temp.explicit]p3: 4918 // A definition of a member class of a class template shall be in scope 4919 // at the point of an explicit instantiation of the member class. 4920 CXXRecordDecl *Def 4921 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition()); 4922 if (!Def) { 4923 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) 4924 << 0 << Record->getDeclName() << Record->getDeclContext(); 4925 Diag(Pattern->getLocation(), diag::note_forward_declaration) 4926 << Pattern; 4927 return true; 4928 } else { 4929 if (InstantiateClass(NameLoc, Record, Def, 4930 getTemplateInstantiationArgs(Record), 4931 TSK)) 4932 return true; 4933 4934 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4935 if (!RecordDef) 4936 return true; 4937 } 4938 } 4939 4940 // Instantiate all of the members of the class. 4941 InstantiateClassMembers(NameLoc, RecordDef, 4942 getTemplateInstantiationArgs(Record), TSK); 4943 4944 if (TSK == TSK_ExplicitInstantiationDefinition) 4945 MarkVTableUsed(NameLoc, RecordDef, true); 4946 4947 // FIXME: We don't have any representation for explicit instantiations of 4948 // member classes. Such a representation is not needed for compilation, but it 4949 // should be available for clients that want to see all of the declarations in 4950 // the source code. 4951 return TagD; 4952} 4953 4954Sema::DeclResult Sema::ActOnExplicitInstantiation(Scope *S, 4955 SourceLocation ExternLoc, 4956 SourceLocation TemplateLoc, 4957 Declarator &D) { 4958 // Explicit instantiations always require a name. 4959 // TODO: check if/when DNInfo should replace Name. 4960 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 4961 DeclarationName Name = NameInfo.getName(); 4962 if (!Name) { 4963 if (!D.isInvalidType()) 4964 Diag(D.getDeclSpec().getSourceRange().getBegin(), 4965 diag::err_explicit_instantiation_requires_name) 4966 << D.getDeclSpec().getSourceRange() 4967 << D.getSourceRange(); 4968 4969 return true; 4970 } 4971 4972 // The scope passed in may not be a decl scope. Zip up the scope tree until 4973 // we find one that is. 4974 while ((S->getFlags() & Scope::DeclScope) == 0 || 4975 (S->getFlags() & Scope::TemplateParamScope) != 0) 4976 S = S->getParent(); 4977 4978 // Determine the type of the declaration. 4979 TypeSourceInfo *T = GetTypeForDeclarator(D, S); 4980 QualType R = T->getType(); 4981 if (R.isNull()) 4982 return true; 4983 4984 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 4985 // Cannot explicitly instantiate a typedef. 4986 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) 4987 << Name; 4988 return true; 4989 } 4990 4991 // C++0x [temp.explicit]p1: 4992 // [...] An explicit instantiation of a function template shall not use the 4993 // inline or constexpr specifiers. 4994 // Presumably, this also applies to member functions of class templates as 4995 // well. 4996 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x) 4997 Diag(D.getDeclSpec().getInlineSpecLoc(), 4998 diag::err_explicit_instantiation_inline) 4999 <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 5000 5001 // FIXME: check for constexpr specifier. 5002 5003 // C++0x [temp.explicit]p2: 5004 // There are two forms of explicit instantiation: an explicit instantiation 5005 // definition and an explicit instantiation declaration. An explicit 5006 // instantiation declaration begins with the extern keyword. [...] 5007 TemplateSpecializationKind TSK 5008 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 5009 : TSK_ExplicitInstantiationDeclaration; 5010 5011 LookupResult Previous(*this, NameInfo, LookupOrdinaryName); 5012 LookupParsedName(Previous, S, &D.getCXXScopeSpec()); 5013 5014 if (!R->isFunctionType()) { 5015 // C++ [temp.explicit]p1: 5016 // A [...] static data member of a class template can be explicitly 5017 // instantiated from the member definition associated with its class 5018 // template. 5019 if (Previous.isAmbiguous()) 5020 return true; 5021 5022 VarDecl *Prev = Previous.getAsSingle<VarDecl>(); 5023 if (!Prev || !Prev->isStaticDataMember()) { 5024 // We expect to see a data data member here. 5025 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) 5026 << Name; 5027 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 5028 P != PEnd; ++P) 5029 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); 5030 return true; 5031 } 5032 5033 if (!Prev->getInstantiatedFromStaticDataMember()) { 5034 // FIXME: Check for explicit specialization? 5035 Diag(D.getIdentifierLoc(), 5036 diag::err_explicit_instantiation_data_member_not_instantiated) 5037 << Prev; 5038 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); 5039 // FIXME: Can we provide a note showing where this was declared? 5040 return true; 5041 } 5042 5043 // C++0x [temp.explicit]p2: 5044 // If the explicit instantiation is for a member function, a member class 5045 // or a static data member of a class template specialization, the name of 5046 // the class template specialization in the qualified-id for the member 5047 // name shall be a simple-template-id. 5048 // 5049 // C++98 has the same restriction, just worded differently. 5050 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5051 Diag(D.getIdentifierLoc(), 5052 diag::ext_explicit_instantiation_without_qualified_id) 5053 << Prev << D.getCXXScopeSpec().getRange(); 5054 5055 // Check the scope of this explicit instantiation. 5056 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); 5057 5058 // Verify that it is okay to explicitly instantiate here. 5059 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); 5060 assert(MSInfo && "Missing static data member specialization info?"); 5061 bool HasNoEffect = false; 5062 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, 5063 MSInfo->getTemplateSpecializationKind(), 5064 MSInfo->getPointOfInstantiation(), 5065 HasNoEffect)) 5066 return true; 5067 if (HasNoEffect) 5068 return (Decl*) 0; 5069 5070 // Instantiate static data member. 5071 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5072 if (TSK == TSK_ExplicitInstantiationDefinition) 5073 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev); 5074 5075 // FIXME: Create an ExplicitInstantiation node? 5076 return (Decl*) 0; 5077 } 5078 5079 // If the declarator is a template-id, translate the parser's template 5080 // argument list into our AST format. 5081 bool HasExplicitTemplateArgs = false; 5082 TemplateArgumentListInfo TemplateArgs; 5083 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 5084 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 5085 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 5086 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 5087 ASTTemplateArgsPtr TemplateArgsPtr(*this, 5088 TemplateId->getTemplateArgs(), 5089 TemplateId->NumArgs); 5090 translateTemplateArguments(TemplateArgsPtr, TemplateArgs); 5091 HasExplicitTemplateArgs = true; 5092 TemplateArgsPtr.release(); 5093 } 5094 5095 // C++ [temp.explicit]p1: 5096 // A [...] function [...] can be explicitly instantiated from its template. 5097 // A member function [...] of a class template can be explicitly 5098 // instantiated from the member definition associated with its class 5099 // template. 5100 UnresolvedSet<8> Matches; 5101 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 5102 P != PEnd; ++P) { 5103 NamedDecl *Prev = *P; 5104 if (!HasExplicitTemplateArgs) { 5105 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { 5106 if (Context.hasSameUnqualifiedType(Method->getType(), R)) { 5107 Matches.clear(); 5108 5109 Matches.addDecl(Method, P.getAccess()); 5110 if (Method->getTemplateSpecializationKind() == TSK_Undeclared) 5111 break; 5112 } 5113 } 5114 } 5115 5116 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); 5117 if (!FunTmpl) 5118 continue; 5119 5120 TemplateDeductionInfo Info(Context, D.getIdentifierLoc()); 5121 FunctionDecl *Specialization = 0; 5122 if (TemplateDeductionResult TDK 5123 = DeduceTemplateArguments(FunTmpl, 5124 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 5125 R, Specialization, Info)) { 5126 // FIXME: Keep track of almost-matches? 5127 (void)TDK; 5128 continue; 5129 } 5130 5131 Matches.addDecl(Specialization, P.getAccess()); 5132 } 5133 5134 // Find the most specialized function template specialization. 5135 UnresolvedSetIterator Result 5136 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, 5137 D.getIdentifierLoc(), 5138 PDiag(diag::err_explicit_instantiation_not_known) << Name, 5139 PDiag(diag::err_explicit_instantiation_ambiguous) << Name, 5140 PDiag(diag::note_explicit_instantiation_candidate)); 5141 5142 if (Result == Matches.end()) 5143 return true; 5144 5145 // Ignore access control bits, we don't need them for redeclaration checking. 5146 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 5147 5148 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { 5149 Diag(D.getIdentifierLoc(), 5150 diag::err_explicit_instantiation_member_function_not_instantiated) 5151 << Specialization 5152 << (Specialization->getTemplateSpecializationKind() == 5153 TSK_ExplicitSpecialization); 5154 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); 5155 return true; 5156 } 5157 5158 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration(); 5159 if (!PrevDecl && Specialization->isThisDeclarationADefinition()) 5160 PrevDecl = Specialization; 5161 5162 if (PrevDecl) { 5163 bool HasNoEffect = false; 5164 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, 5165 PrevDecl, 5166 PrevDecl->getTemplateSpecializationKind(), 5167 PrevDecl->getPointOfInstantiation(), 5168 HasNoEffect)) 5169 return true; 5170 5171 // FIXME: We may still want to build some representation of this 5172 // explicit specialization. 5173 if (HasNoEffect) 5174 return (Decl*) 0; 5175 } 5176 5177 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5178 5179 if (TSK == TSK_ExplicitInstantiationDefinition) 5180 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization); 5181 5182 // C++0x [temp.explicit]p2: 5183 // If the explicit instantiation is for a member function, a member class 5184 // or a static data member of a class template specialization, the name of 5185 // the class template specialization in the qualified-id for the member 5186 // name shall be a simple-template-id. 5187 // 5188 // C++98 has the same restriction, just worded differently. 5189 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); 5190 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && 5191 D.getCXXScopeSpec().isSet() && 5192 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5193 Diag(D.getIdentifierLoc(), 5194 diag::ext_explicit_instantiation_without_qualified_id) 5195 << Specialization << D.getCXXScopeSpec().getRange(); 5196 5197 CheckExplicitInstantiationScope(*this, 5198 FunTmpl? (NamedDecl *)FunTmpl 5199 : Specialization->getInstantiatedFromMemberFunction(), 5200 D.getIdentifierLoc(), 5201 D.getCXXScopeSpec().isSet()); 5202 5203 // FIXME: Create some kind of ExplicitInstantiationDecl here. 5204 return (Decl*) 0; 5205} 5206 5207Sema::TypeResult 5208Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5209 const CXXScopeSpec &SS, IdentifierInfo *Name, 5210 SourceLocation TagLoc, SourceLocation NameLoc) { 5211 // This has to hold, because SS is expected to be defined. 5212 assert(Name && "Expected a name in a dependent tag"); 5213 5214 NestedNameSpecifier *NNS 5215 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5216 if (!NNS) 5217 return true; 5218 5219 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5220 5221 if (TUK == TUK_Declaration || TUK == TUK_Definition) { 5222 Diag(NameLoc, diag::err_dependent_tag_decl) 5223 << (TUK == TUK_Definition) << Kind << SS.getRange(); 5224 return true; 5225 } 5226 5227 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind); 5228 return ParsedType::make(Context.getDependentNameType(Kwd, NNS, Name)); 5229} 5230 5231Sema::TypeResult 5232Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, 5233 const CXXScopeSpec &SS, const IdentifierInfo &II, 5234 SourceLocation IdLoc) { 5235 NestedNameSpecifier *NNS 5236 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5237 if (!NNS) 5238 return true; 5239 5240 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() && 5241 !getLangOptions().CPlusPlus0x) 5242 Diag(TypenameLoc, diag::ext_typename_outside_of_template) 5243 << FixItHint::CreateRemoval(TypenameLoc); 5244 5245 QualType T = CheckTypenameType(ETK_Typename, NNS, II, 5246 TypenameLoc, SS.getRange(), IdLoc); 5247 if (T.isNull()) 5248 return true; 5249 5250 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); 5251 if (isa<DependentNameType>(T)) { 5252 DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc()); 5253 TL.setKeywordLoc(TypenameLoc); 5254 TL.setQualifierRange(SS.getRange()); 5255 TL.setNameLoc(IdLoc); 5256 } else { 5257 ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc()); 5258 TL.setKeywordLoc(TypenameLoc); 5259 TL.setQualifierRange(SS.getRange()); 5260 cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc); 5261 } 5262 5263 return CreateParsedType(T, TSI); 5264} 5265 5266Sema::TypeResult 5267Sema::ActOnTypenameType(Scope *S, SourceLocation TypenameLoc, 5268 const CXXScopeSpec &SS, SourceLocation TemplateLoc, 5269 ParsedType Ty) { 5270 if (TypenameLoc.isValid() && S && !S->getTemplateParamParent() && 5271 !getLangOptions().CPlusPlus0x) 5272 Diag(TypenameLoc, diag::ext_typename_outside_of_template) 5273 << FixItHint::CreateRemoval(TypenameLoc); 5274 5275 TypeSourceInfo *InnerTSI = 0; 5276 QualType T = GetTypeFromParser(Ty, &InnerTSI); 5277 5278 assert(isa<TemplateSpecializationType>(T) && 5279 "Expected a template specialization type"); 5280 5281 if (computeDeclContext(SS, false)) { 5282 // If we can compute a declaration context, then the "typename" 5283 // keyword was superfluous. Just build an ElaboratedType to keep 5284 // track of the nested-name-specifier. 5285 5286 // Push the inner type, preserving its source locations if possible. 5287 TypeLocBuilder Builder; 5288 if (InnerTSI) 5289 Builder.pushFullCopy(InnerTSI->getTypeLoc()); 5290 else 5291 Builder.push<TemplateSpecializationTypeLoc>(T).initialize(TemplateLoc); 5292 5293 /* Note: NNS already embedded in template specialization type T. */ 5294 T = Context.getElaboratedType(ETK_Typename, /*NNS=*/0, T); 5295 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T); 5296 TL.setKeywordLoc(TypenameLoc); 5297 TL.setQualifierRange(SS.getRange()); 5298 5299 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T); 5300 return CreateParsedType(T, TSI); 5301 } 5302 5303 // TODO: it's really silly that we make a template specialization 5304 // type earlier only to drop it again here. 5305 TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T); 5306 DependentTemplateName *DTN = 5307 TST->getTemplateName().getAsDependentTemplateName(); 5308 assert(DTN && "dependent template has non-dependent name?"); 5309 assert(DTN->getQualifier() 5310 == static_cast<NestedNameSpecifier*>(SS.getScopeRep())); 5311 T = Context.getDependentTemplateSpecializationType(ETK_Typename, 5312 DTN->getQualifier(), 5313 DTN->getIdentifier(), 5314 TST->getNumArgs(), 5315 TST->getArgs()); 5316 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); 5317 DependentTemplateSpecializationTypeLoc TL = 5318 cast<DependentTemplateSpecializationTypeLoc>(TSI->getTypeLoc()); 5319 if (InnerTSI) { 5320 TemplateSpecializationTypeLoc TSTL = 5321 cast<TemplateSpecializationTypeLoc>(InnerTSI->getTypeLoc()); 5322 TL.setLAngleLoc(TSTL.getLAngleLoc()); 5323 TL.setRAngleLoc(TSTL.getRAngleLoc()); 5324 for (unsigned I = 0, E = TST->getNumArgs(); I != E; ++I) 5325 TL.setArgLocInfo(I, TSTL.getArgLocInfo(I)); 5326 } else { 5327 TL.initializeLocal(SourceLocation()); 5328 } 5329 TL.setKeywordLoc(TypenameLoc); 5330 TL.setQualifierRange(SS.getRange()); 5331 return CreateParsedType(T, TSI); 5332} 5333 5334/// \brief Build the type that describes a C++ typename specifier, 5335/// e.g., "typename T::type". 5336QualType 5337Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword, 5338 NestedNameSpecifier *NNS, const IdentifierInfo &II, 5339 SourceLocation KeywordLoc, SourceRange NNSRange, 5340 SourceLocation IILoc) { 5341 CXXScopeSpec SS; 5342 SS.setScopeRep(NNS); 5343 SS.setRange(NNSRange); 5344 5345 DeclContext *Ctx = computeDeclContext(SS); 5346 if (!Ctx) { 5347 // If the nested-name-specifier is dependent and couldn't be 5348 // resolved to a type, build a typename type. 5349 assert(NNS->isDependent()); 5350 return Context.getDependentNameType(Keyword, NNS, &II); 5351 } 5352 5353 // If the nested-name-specifier refers to the current instantiation, 5354 // the "typename" keyword itself is superfluous. In C++03, the 5355 // program is actually ill-formed. However, DR 382 (in C++0x CD1) 5356 // allows such extraneous "typename" keywords, and we retroactively 5357 // apply this DR to C++03 code with only a warning. In any case we continue. 5358 5359 if (RequireCompleteDeclContext(SS, Ctx)) 5360 return QualType(); 5361 5362 DeclarationName Name(&II); 5363 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName); 5364 LookupQualifiedName(Result, Ctx); 5365 unsigned DiagID = 0; 5366 Decl *Referenced = 0; 5367 switch (Result.getResultKind()) { 5368 case LookupResult::NotFound: 5369 DiagID = diag::err_typename_nested_not_found; 5370 break; 5371 5372 case LookupResult::NotFoundInCurrentInstantiation: 5373 // Okay, it's a member of an unknown instantiation. 5374 return Context.getDependentNameType(Keyword, NNS, &II); 5375 5376 case LookupResult::Found: 5377 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { 5378 // We found a type. Build an ElaboratedType, since the 5379 // typename-specifier was just sugar. 5380 return Context.getElaboratedType(ETK_Typename, NNS, 5381 Context.getTypeDeclType(Type)); 5382 } 5383 5384 DiagID = diag::err_typename_nested_not_type; 5385 Referenced = Result.getFoundDecl(); 5386 break; 5387 5388 case LookupResult::FoundUnresolvedValue: 5389 llvm_unreachable("unresolved using decl in non-dependent context"); 5390 return QualType(); 5391 5392 case LookupResult::FoundOverloaded: 5393 DiagID = diag::err_typename_nested_not_type; 5394 Referenced = *Result.begin(); 5395 break; 5396 5397 case LookupResult::Ambiguous: 5398 return QualType(); 5399 } 5400 5401 // If we get here, it's because name lookup did not find a 5402 // type. Emit an appropriate diagnostic and return an error. 5403 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(), 5404 IILoc); 5405 Diag(IILoc, DiagID) << FullRange << Name << Ctx; 5406 if (Referenced) 5407 Diag(Referenced->getLocation(), diag::note_typename_refers_here) 5408 << Name; 5409 return QualType(); 5410} 5411 5412namespace { 5413 // See Sema::RebuildTypeInCurrentInstantiation 5414 class CurrentInstantiationRebuilder 5415 : public TreeTransform<CurrentInstantiationRebuilder> { 5416 SourceLocation Loc; 5417 DeclarationName Entity; 5418 5419 public: 5420 typedef TreeTransform<CurrentInstantiationRebuilder> inherited; 5421 5422 CurrentInstantiationRebuilder(Sema &SemaRef, 5423 SourceLocation Loc, 5424 DeclarationName Entity) 5425 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), 5426 Loc(Loc), Entity(Entity) { } 5427 5428 /// \brief Determine whether the given type \p T has already been 5429 /// transformed. 5430 /// 5431 /// For the purposes of type reconstruction, a type has already been 5432 /// transformed if it is NULL or if it is not dependent. 5433 bool AlreadyTransformed(QualType T) { 5434 return T.isNull() || !T->isDependentType(); 5435 } 5436 5437 /// \brief Returns the location of the entity whose type is being 5438 /// rebuilt. 5439 SourceLocation getBaseLocation() { return Loc; } 5440 5441 /// \brief Returns the name of the entity whose type is being rebuilt. 5442 DeclarationName getBaseEntity() { return Entity; } 5443 5444 /// \brief Sets the "base" location and entity when that 5445 /// information is known based on another transformation. 5446 void setBase(SourceLocation Loc, DeclarationName Entity) { 5447 this->Loc = Loc; 5448 this->Entity = Entity; 5449 } 5450 }; 5451} 5452 5453/// \brief Rebuilds a type within the context of the current instantiation. 5454/// 5455/// The type \p T is part of the type of an out-of-line member definition of 5456/// a class template (or class template partial specialization) that was parsed 5457/// and constructed before we entered the scope of the class template (or 5458/// partial specialization thereof). This routine will rebuild that type now 5459/// that we have entered the declarator's scope, which may produce different 5460/// canonical types, e.g., 5461/// 5462/// \code 5463/// template<typename T> 5464/// struct X { 5465/// typedef T* pointer; 5466/// pointer data(); 5467/// }; 5468/// 5469/// template<typename T> 5470/// typename X<T>::pointer X<T>::data() { ... } 5471/// \endcode 5472/// 5473/// Here, the type "typename X<T>::pointer" will be created as a DependentNameType, 5474/// since we do not know that we can look into X<T> when we parsed the type. 5475/// This function will rebuild the type, performing the lookup of "pointer" 5476/// in X<T> and returning an ElaboratedType whose canonical type is the same 5477/// as the canonical type of T*, allowing the return types of the out-of-line 5478/// definition and the declaration to match. 5479TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T, 5480 SourceLocation Loc, 5481 DeclarationName Name) { 5482 if (!T || !T->getType()->isDependentType()) 5483 return T; 5484 5485 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); 5486 return Rebuilder.TransformType(T); 5487} 5488 5489ExprResult Sema::RebuildExprInCurrentInstantiation(Expr *E) { 5490 CurrentInstantiationRebuilder Rebuilder(*this, E->getExprLoc(), 5491 DeclarationName()); 5492 return Rebuilder.TransformExpr(E); 5493} 5494 5495bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) { 5496 if (SS.isInvalid()) return true; 5497 5498 NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5499 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(), 5500 DeclarationName()); 5501 NestedNameSpecifier *Rebuilt = 5502 Rebuilder.TransformNestedNameSpecifier(NNS, SS.getRange()); 5503 if (!Rebuilt) return true; 5504 5505 SS.setScopeRep(Rebuilt); 5506 return false; 5507} 5508 5509/// \brief Produces a formatted string that describes the binding of 5510/// template parameters to template arguments. 5511std::string 5512Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5513 const TemplateArgumentList &Args) { 5514 // FIXME: For variadic templates, we'll need to get the structured list. 5515 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(), 5516 Args.flat_size()); 5517} 5518 5519std::string 5520Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5521 const TemplateArgument *Args, 5522 unsigned NumArgs) { 5523 std::string Result; 5524 5525 if (!Params || Params->size() == 0 || NumArgs == 0) 5526 return Result; 5527 5528 for (unsigned I = 0, N = Params->size(); I != N; ++I) { 5529 if (I >= NumArgs) 5530 break; 5531 5532 if (I == 0) 5533 Result += "[with "; 5534 else 5535 Result += ", "; 5536 5537 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { 5538 Result += Id->getName(); 5539 } else { 5540 Result += '$'; 5541 Result += llvm::utostr(I); 5542 } 5543 5544 Result += " = "; 5545 5546 switch (Args[I].getKind()) { 5547 case TemplateArgument::Null: 5548 Result += "<no value>"; 5549 break; 5550 5551 case TemplateArgument::Type: { 5552 std::string TypeStr; 5553 Args[I].getAsType().getAsStringInternal(TypeStr, 5554 Context.PrintingPolicy); 5555 Result += TypeStr; 5556 break; 5557 } 5558 5559 case TemplateArgument::Declaration: { 5560 bool Unnamed = true; 5561 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) { 5562 if (ND->getDeclName()) { 5563 Unnamed = false; 5564 Result += ND->getNameAsString(); 5565 } 5566 } 5567 5568 if (Unnamed) { 5569 Result += "<anonymous>"; 5570 } 5571 break; 5572 } 5573 5574 case TemplateArgument::Template: { 5575 std::string Str; 5576 llvm::raw_string_ostream OS(Str); 5577 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy); 5578 Result += OS.str(); 5579 break; 5580 } 5581 5582 case TemplateArgument::Integral: { 5583 Result += Args[I].getAsIntegral()->toString(10); 5584 break; 5585 } 5586 5587 case TemplateArgument::Expression: { 5588 // FIXME: This is non-optimal, since we're regurgitating the 5589 // expression we were given. 5590 std::string Str; 5591 { 5592 llvm::raw_string_ostream OS(Str); 5593 Args[I].getAsExpr()->printPretty(OS, Context, 0, 5594 Context.PrintingPolicy); 5595 } 5596 Result += Str; 5597 break; 5598 } 5599 5600 case TemplateArgument::Pack: 5601 // FIXME: Format template argument packs 5602 Result += "<template argument pack>"; 5603 break; 5604 } 5605 } 5606 5607 Result += ']'; 5608 return Result; 5609} 5610