SemaTemplate.cpp revision 486c883ca29f6b50bb8ded372ad5bb2970fd4101
1//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/ 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7//===----------------------------------------------------------------------===/ 8// 9// This file implements semantic analysis for C++ templates. 10//===----------------------------------------------------------------------===/ 11 12#include "Sema.h" 13#include "Lookup.h" 14#include "TreeTransform.h" 15#include "clang/AST/ASTContext.h" 16#include "clang/AST/Expr.h" 17#include "clang/AST/ExprCXX.h" 18#include "clang/AST/DeclFriend.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Parse/Template.h" 22#include "clang/Basic/LangOptions.h" 23#include "clang/Basic/PartialDiagnostic.h" 24#include "llvm/ADT/StringExtras.h" 25using namespace clang; 26 27/// \brief Determine whether the declaration found is acceptable as the name 28/// of a template and, if so, return that template declaration. Otherwise, 29/// returns NULL. 30static NamedDecl *isAcceptableTemplateName(ASTContext &Context, NamedDecl *D) { 31 if (!D) 32 return 0; 33 34 if (isa<TemplateDecl>(D)) 35 return D; 36 37 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) { 38 // C++ [temp.local]p1: 39 // Like normal (non-template) classes, class templates have an 40 // injected-class-name (Clause 9). The injected-class-name 41 // can be used with or without a template-argument-list. When 42 // it is used without a template-argument-list, it is 43 // equivalent to the injected-class-name followed by the 44 // template-parameters of the class template enclosed in 45 // <>. When it is used with a template-argument-list, it 46 // refers to the specified class template specialization, 47 // which could be the current specialization or another 48 // specialization. 49 if (Record->isInjectedClassName()) { 50 Record = cast<CXXRecordDecl>(Record->getDeclContext()); 51 if (Record->getDescribedClassTemplate()) 52 return Record->getDescribedClassTemplate(); 53 54 if (ClassTemplateSpecializationDecl *Spec 55 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) 56 return Spec->getSpecializedTemplate(); 57 } 58 59 return 0; 60 } 61 62 return 0; 63} 64 65static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) { 66 // The set of class templates we've already seen. 67 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates; 68 LookupResult::Filter filter = R.makeFilter(); 69 while (filter.hasNext()) { 70 NamedDecl *Orig = filter.next(); 71 NamedDecl *Repl = isAcceptableTemplateName(C, Orig->getUnderlyingDecl()); 72 if (!Repl) 73 filter.erase(); 74 else if (Repl != Orig) { 75 76 // C++ [temp.local]p3: 77 // A lookup that finds an injected-class-name (10.2) can result in an 78 // ambiguity in certain cases (for example, if it is found in more than 79 // one base class). If all of the injected-class-names that are found 80 // refer to specializations of the same class template, and if the name 81 // is followed by a template-argument-list, the reference refers to the 82 // class template itself and not a specialization thereof, and is not 83 // ambiguous. 84 // 85 // FIXME: Will we eventually have to do the same for alias templates? 86 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl)) 87 if (!ClassTemplates.insert(ClassTmpl)) { 88 filter.erase(); 89 continue; 90 } 91 92 filter.replace(Repl); 93 } 94 } 95 filter.done(); 96} 97 98TemplateNameKind Sema::isTemplateName(Scope *S, 99 CXXScopeSpec &SS, 100 UnqualifiedId &Name, 101 TypeTy *ObjectTypePtr, 102 bool EnteringContext, 103 TemplateTy &TemplateResult, 104 bool &MemberOfUnknownSpecialization) { 105 assert(getLangOptions().CPlusPlus && "No template names in C!"); 106 107 DeclarationName TName; 108 MemberOfUnknownSpecialization = false; 109 110 switch (Name.getKind()) { 111 case UnqualifiedId::IK_Identifier: 112 TName = DeclarationName(Name.Identifier); 113 break; 114 115 case UnqualifiedId::IK_OperatorFunctionId: 116 TName = Context.DeclarationNames.getCXXOperatorName( 117 Name.OperatorFunctionId.Operator); 118 break; 119 120 case UnqualifiedId::IK_LiteralOperatorId: 121 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier); 122 break; 123 124 default: 125 return TNK_Non_template; 126 } 127 128 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 129 130 LookupResult R(*this, TName, Name.getSourceRange().getBegin(), 131 LookupOrdinaryName); 132 R.suppressDiagnostics(); 133 LookupTemplateName(R, S, SS, ObjectType, EnteringContext, 134 MemberOfUnknownSpecialization); 135 if (R.empty() || R.isAmbiguous()) 136 return TNK_Non_template; 137 138 TemplateName Template; 139 TemplateNameKind TemplateKind; 140 141 unsigned ResultCount = R.end() - R.begin(); 142 if (ResultCount > 1) { 143 // We assume that we'll preserve the qualifier from a function 144 // template name in other ways. 145 Template = Context.getOverloadedTemplateName(R.begin(), R.end()); 146 TemplateKind = TNK_Function_template; 147 } else { 148 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl()); 149 150 if (SS.isSet() && !SS.isInvalid()) { 151 NestedNameSpecifier *Qualifier 152 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 153 Template = Context.getQualifiedTemplateName(Qualifier, false, TD); 154 } else { 155 Template = TemplateName(TD); 156 } 157 158 if (isa<FunctionTemplateDecl>(TD)) 159 TemplateKind = TNK_Function_template; 160 else { 161 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD)); 162 TemplateKind = TNK_Type_template; 163 } 164 } 165 166 TemplateResult = TemplateTy::make(Template); 167 return TemplateKind; 168} 169 170bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II, 171 SourceLocation IILoc, 172 Scope *S, 173 const CXXScopeSpec *SS, 174 TemplateTy &SuggestedTemplate, 175 TemplateNameKind &SuggestedKind) { 176 // We can't recover unless there's a dependent scope specifier preceding the 177 // template name. 178 // FIXME: Typo correction? 179 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) || 180 computeDeclContext(*SS)) 181 return false; 182 183 // The code is missing a 'template' keyword prior to the dependent template 184 // name. 185 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep(); 186 Diag(IILoc, diag::err_template_kw_missing) 187 << Qualifier << II.getName() 188 << FixItHint::CreateInsertion(IILoc, "template "); 189 SuggestedTemplate 190 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II)); 191 SuggestedKind = TNK_Dependent_template_name; 192 return true; 193} 194 195void Sema::LookupTemplateName(LookupResult &Found, 196 Scope *S, CXXScopeSpec &SS, 197 QualType ObjectType, 198 bool EnteringContext, 199 bool &MemberOfUnknownSpecialization) { 200 // Determine where to perform name lookup 201 MemberOfUnknownSpecialization = false; 202 DeclContext *LookupCtx = 0; 203 bool isDependent = false; 204 if (!ObjectType.isNull()) { 205 // This nested-name-specifier occurs in a member access expression, e.g., 206 // x->B::f, and we are looking into the type of the object. 207 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 208 LookupCtx = computeDeclContext(ObjectType); 209 isDependent = ObjectType->isDependentType(); 210 assert((isDependent || !ObjectType->isIncompleteType()) && 211 "Caller should have completed object type"); 212 } else if (SS.isSet()) { 213 // This nested-name-specifier occurs after another nested-name-specifier, 214 // so long into the context associated with the prior nested-name-specifier. 215 LookupCtx = computeDeclContext(SS, EnteringContext); 216 isDependent = isDependentScopeSpecifier(SS); 217 218 // The declaration context must be complete. 219 if (LookupCtx && RequireCompleteDeclContext(SS, LookupCtx)) 220 return; 221 } 222 223 bool ObjectTypeSearchedInScope = false; 224 if (LookupCtx) { 225 // Perform "qualified" name lookup into the declaration context we 226 // computed, which is either the type of the base of a member access 227 // expression or the declaration context associated with a prior 228 // nested-name-specifier. 229 LookupQualifiedName(Found, LookupCtx); 230 231 if (!ObjectType.isNull() && Found.empty()) { 232 // C++ [basic.lookup.classref]p1: 233 // In a class member access expression (5.2.5), if the . or -> token is 234 // immediately followed by an identifier followed by a <, the 235 // identifier must be looked up to determine whether the < is the 236 // beginning of a template argument list (14.2) or a less-than operator. 237 // The identifier is first looked up in the class of the object 238 // expression. If the identifier is not found, it is then looked up in 239 // the context of the entire postfix-expression and shall name a class 240 // or function template. 241 // 242 // FIXME: When we're instantiating a template, do we actually have to 243 // look in the scope of the template? Seems fishy... 244 if (S) LookupName(Found, S); 245 ObjectTypeSearchedInScope = true; 246 } 247 } else if (isDependent) { 248 // We cannot look into a dependent object type or nested nme 249 // specifier. 250 MemberOfUnknownSpecialization = true; 251 return; 252 } else { 253 // Perform unqualified name lookup in the current scope. 254 LookupName(Found, S); 255 } 256 257 if (Found.empty() && !isDependent) { 258 // If we did not find any names, attempt to correct any typos. 259 DeclarationName Name = Found.getLookupName(); 260 if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx, 261 false, CTC_CXXCasts)) { 262 FilterAcceptableTemplateNames(Context, Found); 263 if (!Found.empty() && isa<TemplateDecl>(*Found.begin())) { 264 if (LookupCtx) 265 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest) 266 << Name << LookupCtx << Found.getLookupName() << SS.getRange() 267 << FixItHint::CreateReplacement(Found.getNameLoc(), 268 Found.getLookupName().getAsString()); 269 else 270 Diag(Found.getNameLoc(), diag::err_no_template_suggest) 271 << Name << Found.getLookupName() 272 << FixItHint::CreateReplacement(Found.getNameLoc(), 273 Found.getLookupName().getAsString()); 274 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>()) 275 Diag(Template->getLocation(), diag::note_previous_decl) 276 << Template->getDeclName(); 277 } else 278 Found.clear(); 279 } else { 280 Found.clear(); 281 } 282 } 283 284 FilterAcceptableTemplateNames(Context, Found); 285 if (Found.empty()) 286 return; 287 288 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) { 289 // C++ [basic.lookup.classref]p1: 290 // [...] If the lookup in the class of the object expression finds a 291 // template, the name is also looked up in the context of the entire 292 // postfix-expression and [...] 293 // 294 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(), 295 LookupOrdinaryName); 296 LookupName(FoundOuter, S); 297 FilterAcceptableTemplateNames(Context, FoundOuter); 298 299 if (FoundOuter.empty()) { 300 // - if the name is not found, the name found in the class of the 301 // object expression is used, otherwise 302 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) { 303 // - if the name is found in the context of the entire 304 // postfix-expression and does not name a class template, the name 305 // found in the class of the object expression is used, otherwise 306 } else { 307 // - if the name found is a class template, it must refer to the same 308 // entity as the one found in the class of the object expression, 309 // otherwise the program is ill-formed. 310 if (!Found.isSingleResult() || 311 Found.getFoundDecl()->getCanonicalDecl() 312 != FoundOuter.getFoundDecl()->getCanonicalDecl()) { 313 Diag(Found.getNameLoc(), 314 diag::ext_nested_name_member_ref_lookup_ambiguous) 315 << Found.getLookupName() 316 << ObjectType; 317 Diag(Found.getRepresentativeDecl()->getLocation(), 318 diag::note_ambig_member_ref_object_type) 319 << ObjectType; 320 Diag(FoundOuter.getFoundDecl()->getLocation(), 321 diag::note_ambig_member_ref_scope); 322 323 // Recover by taking the template that we found in the object 324 // expression's type. 325 } 326 } 327 } 328} 329 330/// ActOnDependentIdExpression - Handle a dependent id-expression that 331/// was just parsed. This is only possible with an explicit scope 332/// specifier naming a dependent type. 333Sema::OwningExprResult 334Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS, 335 DeclarationName Name, 336 SourceLocation NameLoc, 337 bool isAddressOfOperand, 338 const TemplateArgumentListInfo *TemplateArgs) { 339 NestedNameSpecifier *Qualifier 340 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 341 342 DeclContext *DC = getFunctionLevelDeclContext(); 343 344 if (!isAddressOfOperand && 345 isa<CXXMethodDecl>(DC) && 346 cast<CXXMethodDecl>(DC)->isInstance()) { 347 QualType ThisType = cast<CXXMethodDecl>(DC)->getThisType(Context); 348 349 // Since the 'this' expression is synthesized, we don't need to 350 // perform the double-lookup check. 351 NamedDecl *FirstQualifierInScope = 0; 352 353 return Owned(CXXDependentScopeMemberExpr::Create(Context, 354 /*This*/ 0, ThisType, 355 /*IsArrow*/ true, 356 /*Op*/ SourceLocation(), 357 Qualifier, SS.getRange(), 358 FirstQualifierInScope, 359 Name, NameLoc, 360 TemplateArgs)); 361 } 362 363 return BuildDependentDeclRefExpr(SS, Name, NameLoc, TemplateArgs); 364} 365 366Sema::OwningExprResult 367Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS, 368 DeclarationName Name, 369 SourceLocation NameLoc, 370 const TemplateArgumentListInfo *TemplateArgs) { 371 return Owned(DependentScopeDeclRefExpr::Create(Context, 372 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 373 SS.getRange(), 374 Name, NameLoc, 375 TemplateArgs)); 376} 377 378/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining 379/// that the template parameter 'PrevDecl' is being shadowed by a new 380/// declaration at location Loc. Returns true to indicate that this is 381/// an error, and false otherwise. 382bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { 383 assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); 384 385 // Microsoft Visual C++ permits template parameters to be shadowed. 386 if (getLangOptions().Microsoft) 387 return false; 388 389 // C++ [temp.local]p4: 390 // A template-parameter shall not be redeclared within its 391 // scope (including nested scopes). 392 Diag(Loc, diag::err_template_param_shadow) 393 << cast<NamedDecl>(PrevDecl)->getDeclName(); 394 Diag(PrevDecl->getLocation(), diag::note_template_param_here); 395 return true; 396} 397 398/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset 399/// the parameter D to reference the templated declaration and return a pointer 400/// to the template declaration. Otherwise, do nothing to D and return null. 401TemplateDecl *Sema::AdjustDeclIfTemplate(DeclPtrTy &D) { 402 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D.getAs<Decl>())) { 403 D = DeclPtrTy::make(Temp->getTemplatedDecl()); 404 return Temp; 405 } 406 return 0; 407} 408 409static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, 410 const ParsedTemplateArgument &Arg) { 411 412 switch (Arg.getKind()) { 413 case ParsedTemplateArgument::Type: { 414 TypeSourceInfo *DI; 415 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); 416 if (!DI) 417 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation()); 418 return TemplateArgumentLoc(TemplateArgument(T), DI); 419 } 420 421 case ParsedTemplateArgument::NonType: { 422 Expr *E = static_cast<Expr *>(Arg.getAsExpr()); 423 return TemplateArgumentLoc(TemplateArgument(E), E); 424 } 425 426 case ParsedTemplateArgument::Template: { 427 TemplateName Template 428 = TemplateName::getFromVoidPointer(Arg.getAsTemplate().get()); 429 return TemplateArgumentLoc(TemplateArgument(Template), 430 Arg.getScopeSpec().getRange(), 431 Arg.getLocation()); 432 } 433 } 434 435 llvm_unreachable("Unhandled parsed template argument"); 436 return TemplateArgumentLoc(); 437} 438 439/// \brief Translates template arguments as provided by the parser 440/// into template arguments used by semantic analysis. 441void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn, 442 TemplateArgumentListInfo &TemplateArgs) { 443 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) 444 TemplateArgs.addArgument(translateTemplateArgument(*this, 445 TemplateArgsIn[I])); 446} 447 448/// ActOnTypeParameter - Called when a C++ template type parameter 449/// (e.g., "typename T") has been parsed. Typename specifies whether 450/// the keyword "typename" was used to declare the type parameter 451/// (otherwise, "class" was used), and KeyLoc is the location of the 452/// "class" or "typename" keyword. ParamName is the name of the 453/// parameter (NULL indicates an unnamed template parameter) and 454/// ParamName is the location of the parameter name (if any). 455/// If the type parameter has a default argument, it will be added 456/// later via ActOnTypeParameterDefault. 457Sema::DeclPtrTy Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, 458 SourceLocation EllipsisLoc, 459 SourceLocation KeyLoc, 460 IdentifierInfo *ParamName, 461 SourceLocation ParamNameLoc, 462 unsigned Depth, unsigned Position) { 463 assert(S->isTemplateParamScope() && 464 "Template type parameter not in template parameter scope!"); 465 bool Invalid = false; 466 467 if (ParamName) { 468 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, ParamNameLoc, 469 LookupOrdinaryName, 470 ForRedeclaration); 471 if (PrevDecl && PrevDecl->isTemplateParameter()) 472 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc, 473 PrevDecl); 474 } 475 476 SourceLocation Loc = ParamNameLoc; 477 if (!ParamName) 478 Loc = KeyLoc; 479 480 TemplateTypeParmDecl *Param 481 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(), 482 Loc, Depth, Position, ParamName, Typename, 483 Ellipsis); 484 if (Invalid) 485 Param->setInvalidDecl(); 486 487 if (ParamName) { 488 // Add the template parameter into the current scope. 489 S->AddDecl(DeclPtrTy::make(Param)); 490 IdResolver.AddDecl(Param); 491 } 492 493 return DeclPtrTy::make(Param); 494} 495 496/// ActOnTypeParameterDefault - Adds a default argument (the type 497/// Default) to the given template type parameter (TypeParam). 498void Sema::ActOnTypeParameterDefault(DeclPtrTy TypeParam, 499 SourceLocation EqualLoc, 500 SourceLocation DefaultLoc, 501 TypeTy *DefaultT) { 502 TemplateTypeParmDecl *Parm 503 = cast<TemplateTypeParmDecl>(TypeParam.getAs<Decl>()); 504 505 TypeSourceInfo *DefaultTInfo; 506 GetTypeFromParser(DefaultT, &DefaultTInfo); 507 508 assert(DefaultTInfo && "expected source information for type"); 509 510 // C++0x [temp.param]p9: 511 // A default template-argument may be specified for any kind of 512 // template-parameter that is not a template parameter pack. 513 if (Parm->isParameterPack()) { 514 Diag(DefaultLoc, diag::err_template_param_pack_default_arg); 515 return; 516 } 517 518 // C++ [temp.param]p14: 519 // A template-parameter shall not be used in its own default argument. 520 // FIXME: Implement this check! Needs a recursive walk over the types. 521 522 // Check the template argument itself. 523 if (CheckTemplateArgument(Parm, DefaultTInfo)) { 524 Parm->setInvalidDecl(); 525 return; 526 } 527 528 Parm->setDefaultArgument(DefaultTInfo, false); 529} 530 531/// \brief Check that the type of a non-type template parameter is 532/// well-formed. 533/// 534/// \returns the (possibly-promoted) parameter type if valid; 535/// otherwise, produces a diagnostic and returns a NULL type. 536QualType 537Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { 538 // We don't allow variably-modified types as the type of non-type template 539 // parameters. 540 if (T->isVariablyModifiedType()) { 541 Diag(Loc, diag::err_variably_modified_nontype_template_param) 542 << T; 543 return QualType(); 544 } 545 546 // C++ [temp.param]p4: 547 // 548 // A non-type template-parameter shall have one of the following 549 // (optionally cv-qualified) types: 550 // 551 // -- integral or enumeration type, 552 if (T->isIntegralType() || T->isEnumeralType() || 553 // -- pointer to object or pointer to function, 554 (T->isPointerType() && 555 (T->getAs<PointerType>()->getPointeeType()->isObjectType() || 556 T->getAs<PointerType>()->getPointeeType()->isFunctionType())) || 557 // -- reference to object or reference to function, 558 T->isReferenceType() || 559 // -- pointer to member. 560 T->isMemberPointerType() || 561 // If T is a dependent type, we can't do the check now, so we 562 // assume that it is well-formed. 563 T->isDependentType()) 564 return T; 565 // C++ [temp.param]p8: 566 // 567 // A non-type template-parameter of type "array of T" or 568 // "function returning T" is adjusted to be of type "pointer to 569 // T" or "pointer to function returning T", respectively. 570 else if (T->isArrayType()) 571 // FIXME: Keep the type prior to promotion? 572 return Context.getArrayDecayedType(T); 573 else if (T->isFunctionType()) 574 // FIXME: Keep the type prior to promotion? 575 return Context.getPointerType(T); 576 577 Diag(Loc, diag::err_template_nontype_parm_bad_type) 578 << T; 579 580 return QualType(); 581} 582 583/// ActOnNonTypeTemplateParameter - Called when a C++ non-type 584/// template parameter (e.g., "int Size" in "template<int Size> 585/// class Array") has been parsed. S is the current scope and D is 586/// the parsed declarator. 587Sema::DeclPtrTy Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, 588 unsigned Depth, 589 unsigned Position) { 590 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 591 QualType T = TInfo->getType(); 592 593 assert(S->isTemplateParamScope() && 594 "Non-type template parameter not in template parameter scope!"); 595 bool Invalid = false; 596 597 IdentifierInfo *ParamName = D.getIdentifier(); 598 if (ParamName) { 599 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, D.getIdentifierLoc(), 600 LookupOrdinaryName, 601 ForRedeclaration); 602 if (PrevDecl && PrevDecl->isTemplateParameter()) 603 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 604 PrevDecl); 605 } 606 607 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); 608 if (T.isNull()) { 609 T = Context.IntTy; // Recover with an 'int' type. 610 Invalid = true; 611 } 612 613 NonTypeTemplateParmDecl *Param 614 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 615 D.getIdentifierLoc(), 616 Depth, Position, ParamName, T, TInfo); 617 if (Invalid) 618 Param->setInvalidDecl(); 619 620 if (D.getIdentifier()) { 621 // Add the template parameter into the current scope. 622 S->AddDecl(DeclPtrTy::make(Param)); 623 IdResolver.AddDecl(Param); 624 } 625 return DeclPtrTy::make(Param); 626} 627 628/// \brief Adds a default argument to the given non-type template 629/// parameter. 630void Sema::ActOnNonTypeTemplateParameterDefault(DeclPtrTy TemplateParamD, 631 SourceLocation EqualLoc, 632 ExprArg DefaultE) { 633 NonTypeTemplateParmDecl *TemplateParm 634 = cast<NonTypeTemplateParmDecl>(TemplateParamD.getAs<Decl>()); 635 Expr *Default = static_cast<Expr *>(DefaultE.get()); 636 637 // C++ [temp.param]p14: 638 // A template-parameter shall not be used in its own default argument. 639 // FIXME: Implement this check! Needs a recursive walk over the types. 640 641 // Check the well-formedness of the default template argument. 642 TemplateArgument Converted; 643 if (CheckTemplateArgument(TemplateParm, TemplateParm->getType(), Default, 644 Converted)) { 645 TemplateParm->setInvalidDecl(); 646 return; 647 } 648 649 TemplateParm->setDefaultArgument(DefaultE.takeAs<Expr>(), false); 650} 651 652 653/// ActOnTemplateTemplateParameter - Called when a C++ template template 654/// parameter (e.g. T in template <template <typename> class T> class array) 655/// has been parsed. S is the current scope. 656Sema::DeclPtrTy Sema::ActOnTemplateTemplateParameter(Scope* S, 657 SourceLocation TmpLoc, 658 TemplateParamsTy *Params, 659 IdentifierInfo *Name, 660 SourceLocation NameLoc, 661 unsigned Depth, 662 unsigned Position) { 663 assert(S->isTemplateParamScope() && 664 "Template template parameter not in template parameter scope!"); 665 666 // Construct the parameter object. 667 TemplateTemplateParmDecl *Param = 668 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 669 TmpLoc, Depth, Position, Name, 670 (TemplateParameterList*)Params); 671 672 // Make sure the parameter is valid. 673 // FIXME: Decl object is not currently invalidated anywhere so this doesn't 674 // do anything yet. However, if the template parameter list or (eventual) 675 // default value is ever invalidated, that will propagate here. 676 bool Invalid = false; 677 if (Invalid) { 678 Param->setInvalidDecl(); 679 } 680 681 // If the tt-param has a name, then link the identifier into the scope 682 // and lookup mechanisms. 683 if (Name) { 684 S->AddDecl(DeclPtrTy::make(Param)); 685 IdResolver.AddDecl(Param); 686 } 687 688 return DeclPtrTy::make(Param); 689} 690 691/// \brief Adds a default argument to the given template template 692/// parameter. 693void Sema::ActOnTemplateTemplateParameterDefault(DeclPtrTy TemplateParamD, 694 SourceLocation EqualLoc, 695 const ParsedTemplateArgument &Default) { 696 TemplateTemplateParmDecl *TemplateParm 697 = cast<TemplateTemplateParmDecl>(TemplateParamD.getAs<Decl>()); 698 699 // C++ [temp.param]p14: 700 // A template-parameter shall not be used in its own default argument. 701 // FIXME: Implement this check! Needs a recursive walk over the types. 702 703 // Check only that we have a template template argument. We don't want to 704 // try to check well-formedness now, because our template template parameter 705 // might have dependent types in its template parameters, which we wouldn't 706 // be able to match now. 707 // 708 // If none of the template template parameter's template arguments mention 709 // other template parameters, we could actually perform more checking here. 710 // However, it isn't worth doing. 711 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); 712 if (DefaultArg.getArgument().getAsTemplate().isNull()) { 713 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) 714 << DefaultArg.getSourceRange(); 715 return; 716 } 717 718 TemplateParm->setDefaultArgument(DefaultArg, false); 719} 720 721/// ActOnTemplateParameterList - Builds a TemplateParameterList that 722/// contains the template parameters in Params/NumParams. 723Sema::TemplateParamsTy * 724Sema::ActOnTemplateParameterList(unsigned Depth, 725 SourceLocation ExportLoc, 726 SourceLocation TemplateLoc, 727 SourceLocation LAngleLoc, 728 DeclPtrTy *Params, unsigned NumParams, 729 SourceLocation RAngleLoc) { 730 if (ExportLoc.isValid()) 731 Diag(ExportLoc, diag::warn_template_export_unsupported); 732 733 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, 734 (NamedDecl**)Params, NumParams, 735 RAngleLoc); 736} 737 738static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) { 739 if (SS.isSet()) 740 T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 741 SS.getRange()); 742} 743 744Sema::DeclResult 745Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, 746 SourceLocation KWLoc, CXXScopeSpec &SS, 747 IdentifierInfo *Name, SourceLocation NameLoc, 748 AttributeList *Attr, 749 TemplateParameterList *TemplateParams, 750 AccessSpecifier AS) { 751 assert(TemplateParams && TemplateParams->size() > 0 && 752 "No template parameters"); 753 assert(TUK != TUK_Reference && "Can only declare or define class templates"); 754 bool Invalid = false; 755 756 // Check that we can declare a template here. 757 if (CheckTemplateDeclScope(S, TemplateParams)) 758 return true; 759 760 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 761 assert(Kind != TTK_Enum && "can't build template of enumerated type"); 762 763 // There is no such thing as an unnamed class template. 764 if (!Name) { 765 Diag(KWLoc, diag::err_template_unnamed_class); 766 return true; 767 } 768 769 // Find any previous declaration with this name. 770 DeclContext *SemanticContext; 771 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, 772 ForRedeclaration); 773 if (SS.isNotEmpty() && !SS.isInvalid()) { 774 SemanticContext = computeDeclContext(SS, true); 775 if (!SemanticContext) { 776 // FIXME: Produce a reasonable diagnostic here 777 return true; 778 } 779 780 if (RequireCompleteDeclContext(SS, SemanticContext)) 781 return true; 782 783 LookupQualifiedName(Previous, SemanticContext); 784 } else { 785 SemanticContext = CurContext; 786 LookupName(Previous, S); 787 } 788 789 if (Previous.isAmbiguous()) 790 return true; 791 792 NamedDecl *PrevDecl = 0; 793 if (Previous.begin() != Previous.end()) 794 PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 795 796 // If there is a previous declaration with the same name, check 797 // whether this is a valid redeclaration. 798 ClassTemplateDecl *PrevClassTemplate 799 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); 800 801 // We may have found the injected-class-name of a class template, 802 // class template partial specialization, or class template specialization. 803 // In these cases, grab the template that is being defined or specialized. 804 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && 805 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { 806 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); 807 PrevClassTemplate 808 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); 809 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { 810 PrevClassTemplate 811 = cast<ClassTemplateSpecializationDecl>(PrevDecl) 812 ->getSpecializedTemplate(); 813 } 814 } 815 816 if (TUK == TUK_Friend) { 817 // C++ [namespace.memdef]p3: 818 // [...] When looking for a prior declaration of a class or a function 819 // declared as a friend, and when the name of the friend class or 820 // function is neither a qualified name nor a template-id, scopes outside 821 // the innermost enclosing namespace scope are not considered. 822 if (!SS.isSet()) { 823 DeclContext *OutermostContext = CurContext; 824 while (!OutermostContext->isFileContext()) 825 OutermostContext = OutermostContext->getLookupParent(); 826 827 if (PrevDecl && 828 (OutermostContext->Equals(PrevDecl->getDeclContext()) || 829 OutermostContext->Encloses(PrevDecl->getDeclContext()))) { 830 SemanticContext = PrevDecl->getDeclContext(); 831 } else { 832 // Declarations in outer scopes don't matter. However, the outermost 833 // context we computed is the semantic context for our new 834 // declaration. 835 PrevDecl = PrevClassTemplate = 0; 836 SemanticContext = OutermostContext; 837 } 838 } 839 840 if (CurContext->isDependentContext()) { 841 // If this is a dependent context, we don't want to link the friend 842 // class template to the template in scope, because that would perform 843 // checking of the template parameter lists that can't be performed 844 // until the outer context is instantiated. 845 PrevDecl = PrevClassTemplate = 0; 846 } 847 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) 848 PrevDecl = PrevClassTemplate = 0; 849 850 if (PrevClassTemplate) { 851 // Ensure that the template parameter lists are compatible. 852 if (!TemplateParameterListsAreEqual(TemplateParams, 853 PrevClassTemplate->getTemplateParameters(), 854 /*Complain=*/true, 855 TPL_TemplateMatch)) 856 return true; 857 858 // C++ [temp.class]p4: 859 // In a redeclaration, partial specialization, explicit 860 // specialization or explicit instantiation of a class template, 861 // the class-key shall agree in kind with the original class 862 // template declaration (7.1.5.3). 863 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); 864 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) { 865 Diag(KWLoc, diag::err_use_with_wrong_tag) 866 << Name 867 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName()); 868 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); 869 Kind = PrevRecordDecl->getTagKind(); 870 } 871 872 // Check for redefinition of this class template. 873 if (TUK == TUK_Definition) { 874 if (TagDecl *Def = PrevRecordDecl->getDefinition()) { 875 Diag(NameLoc, diag::err_redefinition) << Name; 876 Diag(Def->getLocation(), diag::note_previous_definition); 877 // FIXME: Would it make sense to try to "forget" the previous 878 // definition, as part of error recovery? 879 return true; 880 } 881 } 882 } else if (PrevDecl && PrevDecl->isTemplateParameter()) { 883 // Maybe we will complain about the shadowed template parameter. 884 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 885 // Just pretend that we didn't see the previous declaration. 886 PrevDecl = 0; 887 } else if (PrevDecl) { 888 // C++ [temp]p5: 889 // A class template shall not have the same name as any other 890 // template, class, function, object, enumeration, enumerator, 891 // namespace, or type in the same scope (3.3), except as specified 892 // in (14.5.4). 893 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 894 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 895 return true; 896 } 897 898 // Check the template parameter list of this declaration, possibly 899 // merging in the template parameter list from the previous class 900 // template declaration. 901 if (CheckTemplateParameterList(TemplateParams, 902 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0, 903 TPC_ClassTemplate)) 904 Invalid = true; 905 906 if (SS.isSet()) { 907 // If the name of the template was qualified, we must be defining the 908 // template out-of-line. 909 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate && 910 !(TUK == TUK_Friend && CurContext->isDependentContext())) 911 Diag(NameLoc, diag::err_member_def_does_not_match) 912 << Name << SemanticContext << SS.getRange(); 913 } 914 915 CXXRecordDecl *NewClass = 916 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc, 917 PrevClassTemplate? 918 PrevClassTemplate->getTemplatedDecl() : 0, 919 /*DelayTypeCreation=*/true); 920 SetNestedNameSpecifier(NewClass, SS); 921 922 ClassTemplateDecl *NewTemplate 923 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, 924 DeclarationName(Name), TemplateParams, 925 NewClass, PrevClassTemplate); 926 NewClass->setDescribedClassTemplate(NewTemplate); 927 928 // Build the type for the class template declaration now. 929 QualType T = NewTemplate->getInjectedClassNameSpecialization(Context); 930 T = Context.getInjectedClassNameType(NewClass, T); 931 assert(T->isDependentType() && "Class template type is not dependent?"); 932 (void)T; 933 934 // If we are providing an explicit specialization of a member that is a 935 // class template, make a note of that. 936 if (PrevClassTemplate && 937 PrevClassTemplate->getInstantiatedFromMemberTemplate()) 938 PrevClassTemplate->setMemberSpecialization(); 939 940 // Set the access specifier. 941 if (!Invalid && TUK != TUK_Friend) 942 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); 943 944 // Set the lexical context of these templates 945 NewClass->setLexicalDeclContext(CurContext); 946 NewTemplate->setLexicalDeclContext(CurContext); 947 948 if (TUK == TUK_Definition) 949 NewClass->startDefinition(); 950 951 if (Attr) 952 ProcessDeclAttributeList(S, NewClass, Attr); 953 954 if (TUK != TUK_Friend) 955 PushOnScopeChains(NewTemplate, S); 956 else { 957 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { 958 NewTemplate->setAccess(PrevClassTemplate->getAccess()); 959 NewClass->setAccess(PrevClassTemplate->getAccess()); 960 } 961 962 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ 963 PrevClassTemplate != NULL); 964 965 // Friend templates are visible in fairly strange ways. 966 if (!CurContext->isDependentContext()) { 967 DeclContext *DC = SemanticContext->getLookupContext(); 968 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false); 969 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 970 PushOnScopeChains(NewTemplate, EnclosingScope, 971 /* AddToContext = */ false); 972 } 973 974 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 975 NewClass->getLocation(), 976 NewTemplate, 977 /*FIXME:*/NewClass->getLocation()); 978 Friend->setAccess(AS_public); 979 CurContext->addDecl(Friend); 980 } 981 982 if (Invalid) { 983 NewTemplate->setInvalidDecl(); 984 NewClass->setInvalidDecl(); 985 } 986 return DeclPtrTy::make(NewTemplate); 987} 988 989/// \brief Diagnose the presence of a default template argument on a 990/// template parameter, which is ill-formed in certain contexts. 991/// 992/// \returns true if the default template argument should be dropped. 993static bool DiagnoseDefaultTemplateArgument(Sema &S, 994 Sema::TemplateParamListContext TPC, 995 SourceLocation ParamLoc, 996 SourceRange DefArgRange) { 997 switch (TPC) { 998 case Sema::TPC_ClassTemplate: 999 return false; 1000 1001 case Sema::TPC_FunctionTemplate: 1002 // C++ [temp.param]p9: 1003 // A default template-argument shall not be specified in a 1004 // function template declaration or a function template 1005 // definition [...] 1006 // (This sentence is not in C++0x, per DR226). 1007 if (!S.getLangOptions().CPlusPlus0x) 1008 S.Diag(ParamLoc, 1009 diag::err_template_parameter_default_in_function_template) 1010 << DefArgRange; 1011 return false; 1012 1013 case Sema::TPC_ClassTemplateMember: 1014 // C++0x [temp.param]p9: 1015 // A default template-argument shall not be specified in the 1016 // template-parameter-lists of the definition of a member of a 1017 // class template that appears outside of the member's class. 1018 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member) 1019 << DefArgRange; 1020 return true; 1021 1022 case Sema::TPC_FriendFunctionTemplate: 1023 // C++ [temp.param]p9: 1024 // A default template-argument shall not be specified in a 1025 // friend template declaration. 1026 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template) 1027 << DefArgRange; 1028 return true; 1029 1030 // FIXME: C++0x [temp.param]p9 allows default template-arguments 1031 // for friend function templates if there is only a single 1032 // declaration (and it is a definition). Strange! 1033 } 1034 1035 return false; 1036} 1037 1038/// \brief Checks the validity of a template parameter list, possibly 1039/// considering the template parameter list from a previous 1040/// declaration. 1041/// 1042/// If an "old" template parameter list is provided, it must be 1043/// equivalent (per TemplateParameterListsAreEqual) to the "new" 1044/// template parameter list. 1045/// 1046/// \param NewParams Template parameter list for a new template 1047/// declaration. This template parameter list will be updated with any 1048/// default arguments that are carried through from the previous 1049/// template parameter list. 1050/// 1051/// \param OldParams If provided, template parameter list from a 1052/// previous declaration of the same template. Default template 1053/// arguments will be merged from the old template parameter list to 1054/// the new template parameter list. 1055/// 1056/// \param TPC Describes the context in which we are checking the given 1057/// template parameter list. 1058/// 1059/// \returns true if an error occurred, false otherwise. 1060bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, 1061 TemplateParameterList *OldParams, 1062 TemplateParamListContext TPC) { 1063 bool Invalid = false; 1064 1065 // C++ [temp.param]p10: 1066 // The set of default template-arguments available for use with a 1067 // template declaration or definition is obtained by merging the 1068 // default arguments from the definition (if in scope) and all 1069 // declarations in scope in the same way default function 1070 // arguments are (8.3.6). 1071 bool SawDefaultArgument = false; 1072 SourceLocation PreviousDefaultArgLoc; 1073 1074 bool SawParameterPack = false; 1075 SourceLocation ParameterPackLoc; 1076 1077 // Dummy initialization to avoid warnings. 1078 TemplateParameterList::iterator OldParam = NewParams->end(); 1079 if (OldParams) 1080 OldParam = OldParams->begin(); 1081 1082 for (TemplateParameterList::iterator NewParam = NewParams->begin(), 1083 NewParamEnd = NewParams->end(); 1084 NewParam != NewParamEnd; ++NewParam) { 1085 // Variables used to diagnose redundant default arguments 1086 bool RedundantDefaultArg = false; 1087 SourceLocation OldDefaultLoc; 1088 SourceLocation NewDefaultLoc; 1089 1090 // Variables used to diagnose missing default arguments 1091 bool MissingDefaultArg = false; 1092 1093 // C++0x [temp.param]p11: 1094 // If a template parameter of a class template is a template parameter pack, 1095 // it must be the last template parameter. 1096 if (SawParameterPack) { 1097 Diag(ParameterPackLoc, 1098 diag::err_template_param_pack_must_be_last_template_parameter); 1099 Invalid = true; 1100 } 1101 1102 if (TemplateTypeParmDecl *NewTypeParm 1103 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { 1104 // Check the presence of a default argument here. 1105 if (NewTypeParm->hasDefaultArgument() && 1106 DiagnoseDefaultTemplateArgument(*this, TPC, 1107 NewTypeParm->getLocation(), 1108 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc() 1109 .getSourceRange())) 1110 NewTypeParm->removeDefaultArgument(); 1111 1112 // Merge default arguments for template type parameters. 1113 TemplateTypeParmDecl *OldTypeParm 1114 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; 1115 1116 if (NewTypeParm->isParameterPack()) { 1117 assert(!NewTypeParm->hasDefaultArgument() && 1118 "Parameter packs can't have a default argument!"); 1119 SawParameterPack = true; 1120 ParameterPackLoc = NewTypeParm->getLocation(); 1121 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && 1122 NewTypeParm->hasDefaultArgument()) { 1123 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); 1124 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); 1125 SawDefaultArgument = true; 1126 RedundantDefaultArg = true; 1127 PreviousDefaultArgLoc = NewDefaultLoc; 1128 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { 1129 // Merge the default argument from the old declaration to the 1130 // new declaration. 1131 SawDefaultArgument = true; 1132 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), 1133 true); 1134 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); 1135 } else if (NewTypeParm->hasDefaultArgument()) { 1136 SawDefaultArgument = true; 1137 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); 1138 } else if (SawDefaultArgument) 1139 MissingDefaultArg = true; 1140 } else if (NonTypeTemplateParmDecl *NewNonTypeParm 1141 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { 1142 // Check the presence of a default argument here. 1143 if (NewNonTypeParm->hasDefaultArgument() && 1144 DiagnoseDefaultTemplateArgument(*this, TPC, 1145 NewNonTypeParm->getLocation(), 1146 NewNonTypeParm->getDefaultArgument()->getSourceRange())) { 1147 NewNonTypeParm->getDefaultArgument()->Destroy(Context); 1148 NewNonTypeParm->removeDefaultArgument(); 1149 } 1150 1151 // Merge default arguments for non-type template parameters 1152 NonTypeTemplateParmDecl *OldNonTypeParm 1153 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; 1154 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && 1155 NewNonTypeParm->hasDefaultArgument()) { 1156 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1157 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1158 SawDefaultArgument = true; 1159 RedundantDefaultArg = true; 1160 PreviousDefaultArgLoc = NewDefaultLoc; 1161 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { 1162 // Merge the default argument from the old declaration to the 1163 // new declaration. 1164 SawDefaultArgument = true; 1165 // FIXME: We need to create a new kind of "default argument" 1166 // expression that points to a previous template template 1167 // parameter. 1168 NewNonTypeParm->setDefaultArgument( 1169 OldNonTypeParm->getDefaultArgument(), 1170 /*Inherited=*/ true); 1171 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1172 } else if (NewNonTypeParm->hasDefaultArgument()) { 1173 SawDefaultArgument = true; 1174 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1175 } else if (SawDefaultArgument) 1176 MissingDefaultArg = true; 1177 } else { 1178 // Check the presence of a default argument here. 1179 TemplateTemplateParmDecl *NewTemplateParm 1180 = cast<TemplateTemplateParmDecl>(*NewParam); 1181 if (NewTemplateParm->hasDefaultArgument() && 1182 DiagnoseDefaultTemplateArgument(*this, TPC, 1183 NewTemplateParm->getLocation(), 1184 NewTemplateParm->getDefaultArgument().getSourceRange())) 1185 NewTemplateParm->removeDefaultArgument(); 1186 1187 // Merge default arguments for template template parameters 1188 TemplateTemplateParmDecl *OldTemplateParm 1189 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; 1190 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && 1191 NewTemplateParm->hasDefaultArgument()) { 1192 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); 1193 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); 1194 SawDefaultArgument = true; 1195 RedundantDefaultArg = true; 1196 PreviousDefaultArgLoc = NewDefaultLoc; 1197 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { 1198 // Merge the default argument from the old declaration to the 1199 // new declaration. 1200 SawDefaultArgument = true; 1201 // FIXME: We need to create a new kind of "default argument" expression 1202 // that points to a previous template template parameter. 1203 NewTemplateParm->setDefaultArgument( 1204 OldTemplateParm->getDefaultArgument(), 1205 /*Inherited=*/ true); 1206 PreviousDefaultArgLoc 1207 = OldTemplateParm->getDefaultArgument().getLocation(); 1208 } else if (NewTemplateParm->hasDefaultArgument()) { 1209 SawDefaultArgument = true; 1210 PreviousDefaultArgLoc 1211 = NewTemplateParm->getDefaultArgument().getLocation(); 1212 } else if (SawDefaultArgument) 1213 MissingDefaultArg = true; 1214 } 1215 1216 if (RedundantDefaultArg) { 1217 // C++ [temp.param]p12: 1218 // A template-parameter shall not be given default arguments 1219 // by two different declarations in the same scope. 1220 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); 1221 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); 1222 Invalid = true; 1223 } else if (MissingDefaultArg) { 1224 // C++ [temp.param]p11: 1225 // If a template-parameter has a default template-argument, 1226 // all subsequent template-parameters shall have a default 1227 // template-argument supplied. 1228 Diag((*NewParam)->getLocation(), 1229 diag::err_template_param_default_arg_missing); 1230 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); 1231 Invalid = true; 1232 } 1233 1234 // If we have an old template parameter list that we're merging 1235 // in, move on to the next parameter. 1236 if (OldParams) 1237 ++OldParam; 1238 } 1239 1240 return Invalid; 1241} 1242 1243/// \brief Match the given template parameter lists to the given scope 1244/// specifier, returning the template parameter list that applies to the 1245/// name. 1246/// 1247/// \param DeclStartLoc the start of the declaration that has a scope 1248/// specifier or a template parameter list. 1249/// 1250/// \param SS the scope specifier that will be matched to the given template 1251/// parameter lists. This scope specifier precedes a qualified name that is 1252/// being declared. 1253/// 1254/// \param ParamLists the template parameter lists, from the outermost to the 1255/// innermost template parameter lists. 1256/// 1257/// \param NumParamLists the number of template parameter lists in ParamLists. 1258/// 1259/// \param IsFriend Whether to apply the slightly different rules for 1260/// matching template parameters to scope specifiers in friend 1261/// declarations. 1262/// 1263/// \param IsExplicitSpecialization will be set true if the entity being 1264/// declared is an explicit specialization, false otherwise. 1265/// 1266/// \returns the template parameter list, if any, that corresponds to the 1267/// name that is preceded by the scope specifier @p SS. This template 1268/// parameter list may be have template parameters (if we're declaring a 1269/// template) or may have no template parameters (if we're declaring a 1270/// template specialization), or may be NULL (if we were's declaring isn't 1271/// itself a template). 1272TemplateParameterList * 1273Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, 1274 const CXXScopeSpec &SS, 1275 TemplateParameterList **ParamLists, 1276 unsigned NumParamLists, 1277 bool IsFriend, 1278 bool &IsExplicitSpecialization) { 1279 IsExplicitSpecialization = false; 1280 1281 // Find the template-ids that occur within the nested-name-specifier. These 1282 // template-ids will match up with the template parameter lists. 1283 llvm::SmallVector<const TemplateSpecializationType *, 4> 1284 TemplateIdsInSpecifier; 1285 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4> 1286 ExplicitSpecializationsInSpecifier; 1287 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 1288 NNS; NNS = NNS->getPrefix()) { 1289 const Type *T = NNS->getAsType(); 1290 if (!T) break; 1291 1292 // C++0x [temp.expl.spec]p17: 1293 // A member or a member template may be nested within many 1294 // enclosing class templates. In an explicit specialization for 1295 // such a member, the member declaration shall be preceded by a 1296 // template<> for each enclosing class template that is 1297 // explicitly specialized. 1298 // 1299 // Following the existing practice of GNU and EDG, we allow a typedef of a 1300 // template specialization type. 1301 if (const TypedefType *TT = dyn_cast<TypedefType>(T)) 1302 T = TT->LookThroughTypedefs().getTypePtr(); 1303 1304 if (const TemplateSpecializationType *SpecType 1305 = dyn_cast<TemplateSpecializationType>(T)) { 1306 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl(); 1307 if (!Template) 1308 continue; // FIXME: should this be an error? probably... 1309 1310 if (const RecordType *Record = SpecType->getAs<RecordType>()) { 1311 ClassTemplateSpecializationDecl *SpecDecl 1312 = cast<ClassTemplateSpecializationDecl>(Record->getDecl()); 1313 // If the nested name specifier refers to an explicit specialization, 1314 // we don't need a template<> header. 1315 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) { 1316 ExplicitSpecializationsInSpecifier.push_back(SpecDecl); 1317 continue; 1318 } 1319 } 1320 1321 TemplateIdsInSpecifier.push_back(SpecType); 1322 } 1323 } 1324 1325 // Reverse the list of template-ids in the scope specifier, so that we can 1326 // more easily match up the template-ids and the template parameter lists. 1327 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end()); 1328 1329 SourceLocation FirstTemplateLoc = DeclStartLoc; 1330 if (NumParamLists) 1331 FirstTemplateLoc = ParamLists[0]->getTemplateLoc(); 1332 1333 // Match the template-ids found in the specifier to the template parameter 1334 // lists. 1335 unsigned Idx = 0; 1336 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size(); 1337 Idx != NumTemplateIds; ++Idx) { 1338 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0); 1339 bool DependentTemplateId = TemplateId->isDependentType(); 1340 if (Idx >= NumParamLists) { 1341 // We have a template-id without a corresponding template parameter 1342 // list. 1343 1344 // ...which is fine if this is a friend declaration. 1345 if (IsFriend) { 1346 IsExplicitSpecialization = true; 1347 break; 1348 } 1349 1350 if (DependentTemplateId) { 1351 // FIXME: the location information here isn't great. 1352 Diag(SS.getRange().getBegin(), 1353 diag::err_template_spec_needs_template_parameters) 1354 << TemplateId 1355 << SS.getRange(); 1356 } else { 1357 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header) 1358 << SS.getRange() 1359 << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> "); 1360 IsExplicitSpecialization = true; 1361 } 1362 return 0; 1363 } 1364 1365 // Check the template parameter list against its corresponding template-id. 1366 if (DependentTemplateId) { 1367 TemplateParameterList *ExpectedTemplateParams = 0; 1368 1369 // Are there cases in (e.g.) friends where this won't match? 1370 if (const InjectedClassNameType *Injected 1371 = TemplateId->getAs<InjectedClassNameType>()) { 1372 CXXRecordDecl *Record = Injected->getDecl(); 1373 if (ClassTemplatePartialSpecializationDecl *Partial = 1374 dyn_cast<ClassTemplatePartialSpecializationDecl>(Record)) 1375 ExpectedTemplateParams = Partial->getTemplateParameters(); 1376 else 1377 ExpectedTemplateParams = Record->getDescribedClassTemplate() 1378 ->getTemplateParameters(); 1379 } 1380 1381 if (ExpectedTemplateParams) 1382 TemplateParameterListsAreEqual(ParamLists[Idx], 1383 ExpectedTemplateParams, 1384 true, TPL_TemplateMatch); 1385 1386 CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember); 1387 } else if (ParamLists[Idx]->size() > 0) 1388 Diag(ParamLists[Idx]->getTemplateLoc(), 1389 diag::err_template_param_list_matches_nontemplate) 1390 << TemplateId 1391 << ParamLists[Idx]->getSourceRange(); 1392 else 1393 IsExplicitSpecialization = true; 1394 } 1395 1396 // If there were at least as many template-ids as there were template 1397 // parameter lists, then there are no template parameter lists remaining for 1398 // the declaration itself. 1399 if (Idx >= NumParamLists) 1400 return 0; 1401 1402 // If there were too many template parameter lists, complain about that now. 1403 if (Idx != NumParamLists - 1) { 1404 while (Idx < NumParamLists - 1) { 1405 bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0; 1406 Diag(ParamLists[Idx]->getTemplateLoc(), 1407 isExplicitSpecHeader? diag::warn_template_spec_extra_headers 1408 : diag::err_template_spec_extra_headers) 1409 << SourceRange(ParamLists[Idx]->getTemplateLoc(), 1410 ParamLists[Idx]->getRAngleLoc()); 1411 1412 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) { 1413 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(), 1414 diag::note_explicit_template_spec_does_not_need_header) 1415 << ExplicitSpecializationsInSpecifier.back(); 1416 ExplicitSpecializationsInSpecifier.pop_back(); 1417 } 1418 1419 ++Idx; 1420 } 1421 } 1422 1423 // Return the last template parameter list, which corresponds to the 1424 // entity being declared. 1425 return ParamLists[NumParamLists - 1]; 1426} 1427 1428QualType Sema::CheckTemplateIdType(TemplateName Name, 1429 SourceLocation TemplateLoc, 1430 const TemplateArgumentListInfo &TemplateArgs) { 1431 TemplateDecl *Template = Name.getAsTemplateDecl(); 1432 if (!Template) { 1433 // The template name does not resolve to a template, so we just 1434 // build a dependent template-id type. 1435 return Context.getTemplateSpecializationType(Name, TemplateArgs); 1436 } 1437 1438 // Check that the template argument list is well-formed for this 1439 // template. 1440 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(), 1441 TemplateArgs.size()); 1442 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs, 1443 false, Converted)) 1444 return QualType(); 1445 1446 assert((Converted.structuredSize() == 1447 Template->getTemplateParameters()->size()) && 1448 "Converted template argument list is too short!"); 1449 1450 QualType CanonType; 1451 1452 if (Name.isDependent() || 1453 TemplateSpecializationType::anyDependentTemplateArguments( 1454 TemplateArgs)) { 1455 // This class template specialization is a dependent 1456 // type. Therefore, its canonical type is another class template 1457 // specialization type that contains all of the converted 1458 // arguments in canonical form. This ensures that, e.g., A<T> and 1459 // A<T, T> have identical types when A is declared as: 1460 // 1461 // template<typename T, typename U = T> struct A; 1462 TemplateName CanonName = Context.getCanonicalTemplateName(Name); 1463 CanonType = Context.getTemplateSpecializationType(CanonName, 1464 Converted.getFlatArguments(), 1465 Converted.flatSize()); 1466 1467 // FIXME: CanonType is not actually the canonical type, and unfortunately 1468 // it is a TemplateSpecializationType that we will never use again. 1469 // In the future, we need to teach getTemplateSpecializationType to only 1470 // build the canonical type and return that to us. 1471 CanonType = Context.getCanonicalType(CanonType); 1472 1473 // This might work out to be a current instantiation, in which 1474 // case the canonical type needs to be the InjectedClassNameType. 1475 // 1476 // TODO: in theory this could be a simple hashtable lookup; most 1477 // changes to CurContext don't change the set of current 1478 // instantiations. 1479 if (isa<ClassTemplateDecl>(Template)) { 1480 for (DeclContext *Ctx = CurContext; Ctx; Ctx = Ctx->getLookupParent()) { 1481 // If we get out to a namespace, we're done. 1482 if (Ctx->isFileContext()) break; 1483 1484 // If this isn't a record, keep looking. 1485 CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx); 1486 if (!Record) continue; 1487 1488 // Look for one of the two cases with InjectedClassNameTypes 1489 // and check whether it's the same template. 1490 if (!isa<ClassTemplatePartialSpecializationDecl>(Record) && 1491 !Record->getDescribedClassTemplate()) 1492 continue; 1493 1494 // Fetch the injected class name type and check whether its 1495 // injected type is equal to the type we just built. 1496 QualType ICNT = Context.getTypeDeclType(Record); 1497 QualType Injected = cast<InjectedClassNameType>(ICNT) 1498 ->getInjectedSpecializationType(); 1499 1500 if (CanonType != Injected->getCanonicalTypeInternal()) 1501 continue; 1502 1503 // If so, the canonical type of this TST is the injected 1504 // class name type of the record we just found. 1505 assert(ICNT.isCanonical()); 1506 CanonType = ICNT; 1507 break; 1508 } 1509 } 1510 } else if (ClassTemplateDecl *ClassTemplate 1511 = dyn_cast<ClassTemplateDecl>(Template)) { 1512 // Find the class template specialization declaration that 1513 // corresponds to these arguments. 1514 llvm::FoldingSetNodeID ID; 1515 ClassTemplateSpecializationDecl::Profile(ID, 1516 Converted.getFlatArguments(), 1517 Converted.flatSize(), 1518 Context); 1519 void *InsertPos = 0; 1520 ClassTemplateSpecializationDecl *Decl 1521 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 1522 if (!Decl) { 1523 // This is the first time we have referenced this class template 1524 // specialization. Create the canonical declaration and add it to 1525 // the set of specializations. 1526 Decl = ClassTemplateSpecializationDecl::Create(Context, 1527 ClassTemplate->getTemplatedDecl()->getTagKind(), 1528 ClassTemplate->getDeclContext(), 1529 ClassTemplate->getLocation(), 1530 ClassTemplate, 1531 Converted, 0); 1532 ClassTemplate->getSpecializations().InsertNode(Decl, InsertPos); 1533 Decl->setLexicalDeclContext(CurContext); 1534 } 1535 1536 CanonType = Context.getTypeDeclType(Decl); 1537 assert(isa<RecordType>(CanonType) && 1538 "type of non-dependent specialization is not a RecordType"); 1539 } 1540 1541 // Build the fully-sugared type for this class template 1542 // specialization, which refers back to the class template 1543 // specialization we created or found. 1544 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); 1545} 1546 1547Action::TypeResult 1548Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc, 1549 SourceLocation LAngleLoc, 1550 ASTTemplateArgsPtr TemplateArgsIn, 1551 SourceLocation RAngleLoc) { 1552 TemplateName Template = TemplateD.getAsVal<TemplateName>(); 1553 1554 // Translate the parser's template argument list in our AST format. 1555 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 1556 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 1557 1558 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); 1559 TemplateArgsIn.release(); 1560 1561 if (Result.isNull()) 1562 return true; 1563 1564 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result); 1565 TemplateSpecializationTypeLoc TL 1566 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc()); 1567 TL.setTemplateNameLoc(TemplateLoc); 1568 TL.setLAngleLoc(LAngleLoc); 1569 TL.setRAngleLoc(RAngleLoc); 1570 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) 1571 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); 1572 1573 return CreateLocInfoType(Result, DI).getAsOpaquePtr(); 1574} 1575 1576Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult, 1577 TagUseKind TUK, 1578 DeclSpec::TST TagSpec, 1579 SourceLocation TagLoc) { 1580 if (TypeResult.isInvalid()) 1581 return Sema::TypeResult(); 1582 1583 // FIXME: preserve source info, ideally without copying the DI. 1584 TypeSourceInfo *DI; 1585 QualType Type = GetTypeFromParser(TypeResult.get(), &DI); 1586 1587 // Verify the tag specifier. 1588 TagTypeKind TagKind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 1589 1590 if (const RecordType *RT = Type->getAs<RecordType>()) { 1591 RecordDecl *D = RT->getDecl(); 1592 1593 IdentifierInfo *Id = D->getIdentifier(); 1594 assert(Id && "templated class must have an identifier"); 1595 1596 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) { 1597 Diag(TagLoc, diag::err_use_with_wrong_tag) 1598 << Type 1599 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName()); 1600 Diag(D->getLocation(), diag::note_previous_use); 1601 } 1602 } 1603 1604 ElaboratedTypeKeyword Keyword 1605 = TypeWithKeyword::getKeywordForTagTypeKind(TagKind); 1606 QualType ElabType = Context.getElaboratedType(Keyword, /*NNS=*/0, Type); 1607 1608 return ElabType.getAsOpaquePtr(); 1609} 1610 1611Sema::OwningExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS, 1612 LookupResult &R, 1613 bool RequiresADL, 1614 const TemplateArgumentListInfo &TemplateArgs) { 1615 // FIXME: Can we do any checking at this point? I guess we could check the 1616 // template arguments that we have against the template name, if the template 1617 // name refers to a single template. That's not a terribly common case, 1618 // though. 1619 1620 // These should be filtered out by our callers. 1621 assert(!R.empty() && "empty lookup results when building templateid"); 1622 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid"); 1623 1624 NestedNameSpecifier *Qualifier = 0; 1625 SourceRange QualifierRange; 1626 if (SS.isSet()) { 1627 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 1628 QualifierRange = SS.getRange(); 1629 } 1630 1631 // We don't want lookup warnings at this point. 1632 R.suppressDiagnostics(); 1633 1634 bool Dependent 1635 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 1636 &TemplateArgs); 1637 UnresolvedLookupExpr *ULE 1638 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1639 Qualifier, QualifierRange, 1640 R.getLookupName(), R.getNameLoc(), 1641 RequiresADL, TemplateArgs, 1642 R.begin(), R.end()); 1643 1644 return Owned(ULE); 1645} 1646 1647// We actually only call this from template instantiation. 1648Sema::OwningExprResult 1649Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS, 1650 DeclarationName Name, 1651 SourceLocation NameLoc, 1652 const TemplateArgumentListInfo &TemplateArgs) { 1653 DeclContext *DC; 1654 if (!(DC = computeDeclContext(SS, false)) || 1655 DC->isDependentContext() || 1656 RequireCompleteDeclContext(SS, DC)) 1657 return BuildDependentDeclRefExpr(SS, Name, NameLoc, &TemplateArgs); 1658 1659 bool MemberOfUnknownSpecialization; 1660 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1661 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false, 1662 MemberOfUnknownSpecialization); 1663 1664 if (R.isAmbiguous()) 1665 return ExprError(); 1666 1667 if (R.empty()) { 1668 Diag(NameLoc, diag::err_template_kw_refers_to_non_template) 1669 << Name << SS.getRange(); 1670 return ExprError(); 1671 } 1672 1673 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) { 1674 Diag(NameLoc, diag::err_template_kw_refers_to_class_template) 1675 << (NestedNameSpecifier*) SS.getScopeRep() << Name << SS.getRange(); 1676 Diag(Temp->getLocation(), diag::note_referenced_class_template); 1677 return ExprError(); 1678 } 1679 1680 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs); 1681} 1682 1683/// \brief Form a dependent template name. 1684/// 1685/// This action forms a dependent template name given the template 1686/// name and its (presumably dependent) scope specifier. For 1687/// example, given "MetaFun::template apply", the scope specifier \p 1688/// SS will be "MetaFun::", \p TemplateKWLoc contains the location 1689/// of the "template" keyword, and "apply" is the \p Name. 1690Sema::TemplateTy 1691Sema::ActOnDependentTemplateName(SourceLocation TemplateKWLoc, 1692 CXXScopeSpec &SS, 1693 UnqualifiedId &Name, 1694 TypeTy *ObjectType, 1695 bool EnteringContext) { 1696 DeclContext *LookupCtx = 0; 1697 if (SS.isSet()) 1698 LookupCtx = computeDeclContext(SS, EnteringContext); 1699 if (!LookupCtx && ObjectType) 1700 LookupCtx = computeDeclContext(QualType::getFromOpaquePtr(ObjectType)); 1701 if (LookupCtx) { 1702 // C++0x [temp.names]p5: 1703 // If a name prefixed by the keyword template is not the name of 1704 // a template, the program is ill-formed. [Note: the keyword 1705 // template may not be applied to non-template members of class 1706 // templates. -end note ] [ Note: as is the case with the 1707 // typename prefix, the template prefix is allowed in cases 1708 // where it is not strictly necessary; i.e., when the 1709 // nested-name-specifier or the expression on the left of the -> 1710 // or . is not dependent on a template-parameter, or the use 1711 // does not appear in the scope of a template. -end note] 1712 // 1713 // Note: C++03 was more strict here, because it banned the use of 1714 // the "template" keyword prior to a template-name that was not a 1715 // dependent name. C++ DR468 relaxed this requirement (the 1716 // "template" keyword is now permitted). We follow the C++0x 1717 // rules, even in C++03 mode, retroactively applying the DR. 1718 TemplateTy Template; 1719 bool MemberOfUnknownSpecialization; 1720 TemplateNameKind TNK = isTemplateName(0, SS, Name, ObjectType, 1721 EnteringContext, Template, 1722 MemberOfUnknownSpecialization); 1723 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() && 1724 isa<CXXRecordDecl>(LookupCtx) && 1725 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) { 1726 // This is a dependent template. 1727 } else if (TNK == TNK_Non_template) { 1728 Diag(Name.getSourceRange().getBegin(), 1729 diag::err_template_kw_refers_to_non_template) 1730 << GetNameFromUnqualifiedId(Name) 1731 << Name.getSourceRange() 1732 << TemplateKWLoc; 1733 return TemplateTy(); 1734 } else { 1735 // We found something; return it. 1736 return Template; 1737 } 1738 } 1739 1740 NestedNameSpecifier *Qualifier 1741 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1742 1743 switch (Name.getKind()) { 1744 case UnqualifiedId::IK_Identifier: 1745 return TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1746 Name.Identifier)); 1747 1748 case UnqualifiedId::IK_OperatorFunctionId: 1749 return TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1750 Name.OperatorFunctionId.Operator)); 1751 1752 case UnqualifiedId::IK_LiteralOperatorId: 1753 assert(false && "We don't support these; Parse shouldn't have allowed propagation"); 1754 1755 default: 1756 break; 1757 } 1758 1759 Diag(Name.getSourceRange().getBegin(), 1760 diag::err_template_kw_refers_to_non_template) 1761 << GetNameFromUnqualifiedId(Name) 1762 << Name.getSourceRange() 1763 << TemplateKWLoc; 1764 return TemplateTy(); 1765} 1766 1767bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, 1768 const TemplateArgumentLoc &AL, 1769 TemplateArgumentListBuilder &Converted) { 1770 const TemplateArgument &Arg = AL.getArgument(); 1771 1772 // Check template type parameter. 1773 switch(Arg.getKind()) { 1774 case TemplateArgument::Type: 1775 // C++ [temp.arg.type]p1: 1776 // A template-argument for a template-parameter which is a 1777 // type shall be a type-id. 1778 break; 1779 case TemplateArgument::Template: { 1780 // We have a template type parameter but the template argument 1781 // is a template without any arguments. 1782 SourceRange SR = AL.getSourceRange(); 1783 TemplateName Name = Arg.getAsTemplate(); 1784 Diag(SR.getBegin(), diag::err_template_missing_args) 1785 << Name << SR; 1786 if (TemplateDecl *Decl = Name.getAsTemplateDecl()) 1787 Diag(Decl->getLocation(), diag::note_template_decl_here); 1788 1789 return true; 1790 } 1791 default: { 1792 // We have a template type parameter but the template argument 1793 // is not a type. 1794 SourceRange SR = AL.getSourceRange(); 1795 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; 1796 Diag(Param->getLocation(), diag::note_template_param_here); 1797 1798 return true; 1799 } 1800 } 1801 1802 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo())) 1803 return true; 1804 1805 // Add the converted template type argument. 1806 Converted.Append( 1807 TemplateArgument(Context.getCanonicalType(Arg.getAsType()))); 1808 return false; 1809} 1810 1811/// \brief Substitute template arguments into the default template argument for 1812/// the given template type parameter. 1813/// 1814/// \param SemaRef the semantic analysis object for which we are performing 1815/// the substitution. 1816/// 1817/// \param Template the template that we are synthesizing template arguments 1818/// for. 1819/// 1820/// \param TemplateLoc the location of the template name that started the 1821/// template-id we are checking. 1822/// 1823/// \param RAngleLoc the location of the right angle bracket ('>') that 1824/// terminates the template-id. 1825/// 1826/// \param Param the template template parameter whose default we are 1827/// substituting into. 1828/// 1829/// \param Converted the list of template arguments provided for template 1830/// parameters that precede \p Param in the template parameter list. 1831/// 1832/// \returns the substituted template argument, or NULL if an error occurred. 1833static TypeSourceInfo * 1834SubstDefaultTemplateArgument(Sema &SemaRef, 1835 TemplateDecl *Template, 1836 SourceLocation TemplateLoc, 1837 SourceLocation RAngleLoc, 1838 TemplateTypeParmDecl *Param, 1839 TemplateArgumentListBuilder &Converted) { 1840 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo(); 1841 1842 // If the argument type is dependent, instantiate it now based 1843 // on the previously-computed template arguments. 1844 if (ArgType->getType()->isDependentType()) { 1845 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1846 /*TakeArgs=*/false); 1847 1848 MultiLevelTemplateArgumentList AllTemplateArgs 1849 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1850 1851 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1852 Template, Converted.getFlatArguments(), 1853 Converted.flatSize(), 1854 SourceRange(TemplateLoc, RAngleLoc)); 1855 1856 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, 1857 Param->getDefaultArgumentLoc(), 1858 Param->getDeclName()); 1859 } 1860 1861 return ArgType; 1862} 1863 1864/// \brief Substitute template arguments into the default template argument for 1865/// the given non-type template parameter. 1866/// 1867/// \param SemaRef the semantic analysis object for which we are performing 1868/// the substitution. 1869/// 1870/// \param Template the template that we are synthesizing template arguments 1871/// for. 1872/// 1873/// \param TemplateLoc the location of the template name that started the 1874/// template-id we are checking. 1875/// 1876/// \param RAngleLoc the location of the right angle bracket ('>') that 1877/// terminates the template-id. 1878/// 1879/// \param Param the non-type template parameter whose default we are 1880/// substituting into. 1881/// 1882/// \param Converted the list of template arguments provided for template 1883/// parameters that precede \p Param in the template parameter list. 1884/// 1885/// \returns the substituted template argument, or NULL if an error occurred. 1886static Sema::OwningExprResult 1887SubstDefaultTemplateArgument(Sema &SemaRef, 1888 TemplateDecl *Template, 1889 SourceLocation TemplateLoc, 1890 SourceLocation RAngleLoc, 1891 NonTypeTemplateParmDecl *Param, 1892 TemplateArgumentListBuilder &Converted) { 1893 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1894 /*TakeArgs=*/false); 1895 1896 MultiLevelTemplateArgumentList AllTemplateArgs 1897 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1898 1899 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1900 Template, Converted.getFlatArguments(), 1901 Converted.flatSize(), 1902 SourceRange(TemplateLoc, RAngleLoc)); 1903 1904 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); 1905} 1906 1907/// \brief Substitute template arguments into the default template argument for 1908/// the given template template parameter. 1909/// 1910/// \param SemaRef the semantic analysis object for which we are performing 1911/// the substitution. 1912/// 1913/// \param Template the template that we are synthesizing template arguments 1914/// for. 1915/// 1916/// \param TemplateLoc the location of the template name that started the 1917/// template-id we are checking. 1918/// 1919/// \param RAngleLoc the location of the right angle bracket ('>') that 1920/// terminates the template-id. 1921/// 1922/// \param Param the template template parameter whose default we are 1923/// substituting into. 1924/// 1925/// \param Converted the list of template arguments provided for template 1926/// parameters that precede \p Param in the template parameter list. 1927/// 1928/// \returns the substituted template argument, or NULL if an error occurred. 1929static TemplateName 1930SubstDefaultTemplateArgument(Sema &SemaRef, 1931 TemplateDecl *Template, 1932 SourceLocation TemplateLoc, 1933 SourceLocation RAngleLoc, 1934 TemplateTemplateParmDecl *Param, 1935 TemplateArgumentListBuilder &Converted) { 1936 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1937 /*TakeArgs=*/false); 1938 1939 MultiLevelTemplateArgumentList AllTemplateArgs 1940 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1941 1942 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1943 Template, Converted.getFlatArguments(), 1944 Converted.flatSize(), 1945 SourceRange(TemplateLoc, RAngleLoc)); 1946 1947 return SemaRef.SubstTemplateName( 1948 Param->getDefaultArgument().getArgument().getAsTemplate(), 1949 Param->getDefaultArgument().getTemplateNameLoc(), 1950 AllTemplateArgs); 1951} 1952 1953/// \brief If the given template parameter has a default template 1954/// argument, substitute into that default template argument and 1955/// return the corresponding template argument. 1956TemplateArgumentLoc 1957Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template, 1958 SourceLocation TemplateLoc, 1959 SourceLocation RAngleLoc, 1960 Decl *Param, 1961 TemplateArgumentListBuilder &Converted) { 1962 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) { 1963 if (!TypeParm->hasDefaultArgument()) 1964 return TemplateArgumentLoc(); 1965 1966 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template, 1967 TemplateLoc, 1968 RAngleLoc, 1969 TypeParm, 1970 Converted); 1971 if (DI) 1972 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI); 1973 1974 return TemplateArgumentLoc(); 1975 } 1976 1977 if (NonTypeTemplateParmDecl *NonTypeParm 1978 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1979 if (!NonTypeParm->hasDefaultArgument()) 1980 return TemplateArgumentLoc(); 1981 1982 OwningExprResult Arg = SubstDefaultTemplateArgument(*this, Template, 1983 TemplateLoc, 1984 RAngleLoc, 1985 NonTypeParm, 1986 Converted); 1987 if (Arg.isInvalid()) 1988 return TemplateArgumentLoc(); 1989 1990 Expr *ArgE = Arg.takeAs<Expr>(); 1991 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE); 1992 } 1993 1994 TemplateTemplateParmDecl *TempTempParm 1995 = cast<TemplateTemplateParmDecl>(Param); 1996 if (!TempTempParm->hasDefaultArgument()) 1997 return TemplateArgumentLoc(); 1998 1999 TemplateName TName = SubstDefaultTemplateArgument(*this, Template, 2000 TemplateLoc, 2001 RAngleLoc, 2002 TempTempParm, 2003 Converted); 2004 if (TName.isNull()) 2005 return TemplateArgumentLoc(); 2006 2007 return TemplateArgumentLoc(TemplateArgument(TName), 2008 TempTempParm->getDefaultArgument().getTemplateQualifierRange(), 2009 TempTempParm->getDefaultArgument().getTemplateNameLoc()); 2010} 2011 2012/// \brief Check that the given template argument corresponds to the given 2013/// template parameter. 2014bool Sema::CheckTemplateArgument(NamedDecl *Param, 2015 const TemplateArgumentLoc &Arg, 2016 TemplateDecl *Template, 2017 SourceLocation TemplateLoc, 2018 SourceLocation RAngleLoc, 2019 TemplateArgumentListBuilder &Converted, 2020 CheckTemplateArgumentKind CTAK) { 2021 // Check template type parameters. 2022 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) 2023 return CheckTemplateTypeArgument(TTP, Arg, Converted); 2024 2025 // Check non-type template parameters. 2026 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { 2027 // Do substitution on the type of the non-type template parameter 2028 // with the template arguments we've seen thus far. 2029 QualType NTTPType = NTTP->getType(); 2030 if (NTTPType->isDependentType()) { 2031 // Do substitution on the type of the non-type template parameter. 2032 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2033 NTTP, Converted.getFlatArguments(), 2034 Converted.flatSize(), 2035 SourceRange(TemplateLoc, RAngleLoc)); 2036 2037 TemplateArgumentList TemplateArgs(Context, Converted, 2038 /*TakeArgs=*/false); 2039 NTTPType = SubstType(NTTPType, 2040 MultiLevelTemplateArgumentList(TemplateArgs), 2041 NTTP->getLocation(), 2042 NTTP->getDeclName()); 2043 // If that worked, check the non-type template parameter type 2044 // for validity. 2045 if (!NTTPType.isNull()) 2046 NTTPType = CheckNonTypeTemplateParameterType(NTTPType, 2047 NTTP->getLocation()); 2048 if (NTTPType.isNull()) 2049 return true; 2050 } 2051 2052 switch (Arg.getArgument().getKind()) { 2053 case TemplateArgument::Null: 2054 assert(false && "Should never see a NULL template argument here"); 2055 return true; 2056 2057 case TemplateArgument::Expression: { 2058 Expr *E = Arg.getArgument().getAsExpr(); 2059 TemplateArgument Result; 2060 if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK)) 2061 return true; 2062 2063 Converted.Append(Result); 2064 break; 2065 } 2066 2067 case TemplateArgument::Declaration: 2068 case TemplateArgument::Integral: 2069 // We've already checked this template argument, so just copy 2070 // it to the list of converted arguments. 2071 Converted.Append(Arg.getArgument()); 2072 break; 2073 2074 case TemplateArgument::Template: 2075 // We were given a template template argument. It may not be ill-formed; 2076 // see below. 2077 if (DependentTemplateName *DTN 2078 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) { 2079 // We have a template argument such as \c T::template X, which we 2080 // parsed as a template template argument. However, since we now 2081 // know that we need a non-type template argument, convert this 2082 // template name into an expression. 2083 Expr *E = DependentScopeDeclRefExpr::Create(Context, 2084 DTN->getQualifier(), 2085 Arg.getTemplateQualifierRange(), 2086 DTN->getIdentifier(), 2087 Arg.getTemplateNameLoc()); 2088 2089 TemplateArgument Result; 2090 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 2091 return true; 2092 2093 Converted.Append(Result); 2094 break; 2095 } 2096 2097 // We have a template argument that actually does refer to a class 2098 // template, template alias, or template template parameter, and 2099 // therefore cannot be a non-type template argument. 2100 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) 2101 << Arg.getSourceRange(); 2102 2103 Diag(Param->getLocation(), diag::note_template_param_here); 2104 return true; 2105 2106 case TemplateArgument::Type: { 2107 // We have a non-type template parameter but the template 2108 // argument is a type. 2109 2110 // C++ [temp.arg]p2: 2111 // In a template-argument, an ambiguity between a type-id and 2112 // an expression is resolved to a type-id, regardless of the 2113 // form of the corresponding template-parameter. 2114 // 2115 // We warn specifically about this case, since it can be rather 2116 // confusing for users. 2117 QualType T = Arg.getArgument().getAsType(); 2118 SourceRange SR = Arg.getSourceRange(); 2119 if (T->isFunctionType()) 2120 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; 2121 else 2122 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; 2123 Diag(Param->getLocation(), diag::note_template_param_here); 2124 return true; 2125 } 2126 2127 case TemplateArgument::Pack: 2128 llvm_unreachable("Caller must expand template argument packs"); 2129 break; 2130 } 2131 2132 return false; 2133 } 2134 2135 2136 // Check template template parameters. 2137 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); 2138 2139 // Substitute into the template parameter list of the template 2140 // template parameter, since previously-supplied template arguments 2141 // may appear within the template template parameter. 2142 { 2143 // Set up a template instantiation context. 2144 LocalInstantiationScope Scope(*this); 2145 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2146 TempParm, Converted.getFlatArguments(), 2147 Converted.flatSize(), 2148 SourceRange(TemplateLoc, RAngleLoc)); 2149 2150 TemplateArgumentList TemplateArgs(Context, Converted, 2151 /*TakeArgs=*/false); 2152 TempParm = cast_or_null<TemplateTemplateParmDecl>( 2153 SubstDecl(TempParm, CurContext, 2154 MultiLevelTemplateArgumentList(TemplateArgs))); 2155 if (!TempParm) 2156 return true; 2157 2158 // FIXME: TempParam is leaked. 2159 } 2160 2161 switch (Arg.getArgument().getKind()) { 2162 case TemplateArgument::Null: 2163 assert(false && "Should never see a NULL template argument here"); 2164 return true; 2165 2166 case TemplateArgument::Template: 2167 if (CheckTemplateArgument(TempParm, Arg)) 2168 return true; 2169 2170 Converted.Append(Arg.getArgument()); 2171 break; 2172 2173 case TemplateArgument::Expression: 2174 case TemplateArgument::Type: 2175 // We have a template template parameter but the template 2176 // argument does not refer to a template. 2177 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template); 2178 return true; 2179 2180 case TemplateArgument::Declaration: 2181 llvm_unreachable( 2182 "Declaration argument with template template parameter"); 2183 break; 2184 case TemplateArgument::Integral: 2185 llvm_unreachable( 2186 "Integral argument with template template parameter"); 2187 break; 2188 2189 case TemplateArgument::Pack: 2190 llvm_unreachable("Caller must expand template argument packs"); 2191 break; 2192 } 2193 2194 return false; 2195} 2196 2197/// \brief Check that the given template argument list is well-formed 2198/// for specializing the given template. 2199bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, 2200 SourceLocation TemplateLoc, 2201 const TemplateArgumentListInfo &TemplateArgs, 2202 bool PartialTemplateArgs, 2203 TemplateArgumentListBuilder &Converted) { 2204 TemplateParameterList *Params = Template->getTemplateParameters(); 2205 unsigned NumParams = Params->size(); 2206 unsigned NumArgs = TemplateArgs.size(); 2207 bool Invalid = false; 2208 2209 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc(); 2210 2211 bool HasParameterPack = 2212 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); 2213 2214 if ((NumArgs > NumParams && !HasParameterPack) || 2215 (NumArgs < Params->getMinRequiredArguments() && 2216 !PartialTemplateArgs)) { 2217 // FIXME: point at either the first arg beyond what we can handle, 2218 // or the '>', depending on whether we have too many or too few 2219 // arguments. 2220 SourceRange Range; 2221 if (NumArgs > NumParams) 2222 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc); 2223 Diag(TemplateLoc, diag::err_template_arg_list_different_arity) 2224 << (NumArgs > NumParams) 2225 << (isa<ClassTemplateDecl>(Template)? 0 : 2226 isa<FunctionTemplateDecl>(Template)? 1 : 2227 isa<TemplateTemplateParmDecl>(Template)? 2 : 3) 2228 << Template << Range; 2229 Diag(Template->getLocation(), diag::note_template_decl_here) 2230 << Params->getSourceRange(); 2231 Invalid = true; 2232 } 2233 2234 // C++ [temp.arg]p1: 2235 // [...] The type and form of each template-argument specified in 2236 // a template-id shall match the type and form specified for the 2237 // corresponding parameter declared by the template in its 2238 // template-parameter-list. 2239 unsigned ArgIdx = 0; 2240 for (TemplateParameterList::iterator Param = Params->begin(), 2241 ParamEnd = Params->end(); 2242 Param != ParamEnd; ++Param, ++ArgIdx) { 2243 if (ArgIdx > NumArgs && PartialTemplateArgs) 2244 break; 2245 2246 // If we have a template parameter pack, check every remaining template 2247 // argument against that template parameter pack. 2248 if ((*Param)->isTemplateParameterPack()) { 2249 Converted.BeginPack(); 2250 for (; ArgIdx < NumArgs; ++ArgIdx) { 2251 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2252 TemplateLoc, RAngleLoc, Converted)) { 2253 Invalid = true; 2254 break; 2255 } 2256 } 2257 Converted.EndPack(); 2258 continue; 2259 } 2260 2261 if (ArgIdx < NumArgs) { 2262 // Check the template argument we were given. 2263 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2264 TemplateLoc, RAngleLoc, Converted)) 2265 return true; 2266 2267 continue; 2268 } 2269 2270 // We have a default template argument that we will use. 2271 TemplateArgumentLoc Arg; 2272 2273 // Retrieve the default template argument from the template 2274 // parameter. For each kind of template parameter, we substitute the 2275 // template arguments provided thus far and any "outer" template arguments 2276 // (when the template parameter was part of a nested template) into 2277 // the default argument. 2278 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { 2279 if (!TTP->hasDefaultArgument()) { 2280 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2281 break; 2282 } 2283 2284 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this, 2285 Template, 2286 TemplateLoc, 2287 RAngleLoc, 2288 TTP, 2289 Converted); 2290 if (!ArgType) 2291 return true; 2292 2293 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), 2294 ArgType); 2295 } else if (NonTypeTemplateParmDecl *NTTP 2296 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { 2297 if (!NTTP->hasDefaultArgument()) { 2298 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2299 break; 2300 } 2301 2302 Sema::OwningExprResult E = SubstDefaultTemplateArgument(*this, Template, 2303 TemplateLoc, 2304 RAngleLoc, 2305 NTTP, 2306 Converted); 2307 if (E.isInvalid()) 2308 return true; 2309 2310 Expr *Ex = E.takeAs<Expr>(); 2311 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); 2312 } else { 2313 TemplateTemplateParmDecl *TempParm 2314 = cast<TemplateTemplateParmDecl>(*Param); 2315 2316 if (!TempParm->hasDefaultArgument()) { 2317 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2318 break; 2319 } 2320 2321 TemplateName Name = SubstDefaultTemplateArgument(*this, Template, 2322 TemplateLoc, 2323 RAngleLoc, 2324 TempParm, 2325 Converted); 2326 if (Name.isNull()) 2327 return true; 2328 2329 Arg = TemplateArgumentLoc(TemplateArgument(Name), 2330 TempParm->getDefaultArgument().getTemplateQualifierRange(), 2331 TempParm->getDefaultArgument().getTemplateNameLoc()); 2332 } 2333 2334 // Introduce an instantiation record that describes where we are using 2335 // the default template argument. 2336 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, 2337 Converted.getFlatArguments(), 2338 Converted.flatSize(), 2339 SourceRange(TemplateLoc, RAngleLoc)); 2340 2341 // Check the default template argument. 2342 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, 2343 RAngleLoc, Converted)) 2344 return true; 2345 } 2346 2347 return Invalid; 2348} 2349 2350/// \brief Check a template argument against its corresponding 2351/// template type parameter. 2352/// 2353/// This routine implements the semantics of C++ [temp.arg.type]. It 2354/// returns true if an error occurred, and false otherwise. 2355bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, 2356 TypeSourceInfo *ArgInfo) { 2357 assert(ArgInfo && "invalid TypeSourceInfo"); 2358 QualType Arg = ArgInfo->getType(); 2359 2360 // C++ [temp.arg.type]p2: 2361 // A local type, a type with no linkage, an unnamed type or a type 2362 // compounded from any of these types shall not be used as a 2363 // template-argument for a template type-parameter. 2364 // 2365 // FIXME: Perform the unnamed type check. 2366 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); 2367 const TagType *Tag = 0; 2368 if (const EnumType *EnumT = Arg->getAs<EnumType>()) 2369 Tag = EnumT; 2370 else if (const RecordType *RecordT = Arg->getAs<RecordType>()) 2371 Tag = RecordT; 2372 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) { 2373 SourceRange SR = ArgInfo->getTypeLoc().getSourceRange(); 2374 return Diag(SR.getBegin(), diag::err_template_arg_local_type) 2375 << QualType(Tag, 0) << SR; 2376 } else if (Tag && !Tag->getDecl()->getDeclName() && 2377 !Tag->getDecl()->getTypedefForAnonDecl()) { 2378 Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR; 2379 Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here); 2380 return true; 2381 } else if (Arg->isVariablyModifiedType()) { 2382 Diag(SR.getBegin(), diag::err_variably_modified_template_arg) 2383 << Arg; 2384 return true; 2385 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) { 2386 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR; 2387 } 2388 2389 return false; 2390} 2391 2392/// \brief Checks whether the given template argument is the address 2393/// of an object or function according to C++ [temp.arg.nontype]p1. 2394static bool 2395CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S, 2396 NonTypeTemplateParmDecl *Param, 2397 QualType ParamType, 2398 Expr *ArgIn, 2399 TemplateArgument &Converted) { 2400 bool Invalid = false; 2401 Expr *Arg = ArgIn; 2402 QualType ArgType = Arg->getType(); 2403 2404 // See through any implicit casts we added to fix the type. 2405 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2406 Arg = Cast->getSubExpr(); 2407 2408 // C++ [temp.arg.nontype]p1: 2409 // 2410 // A template-argument for a non-type, non-template 2411 // template-parameter shall be one of: [...] 2412 // 2413 // -- the address of an object or function with external 2414 // linkage, including function templates and function 2415 // template-ids but excluding non-static class members, 2416 // expressed as & id-expression where the & is optional if 2417 // the name refers to a function or array, or if the 2418 // corresponding template-parameter is a reference; or 2419 DeclRefExpr *DRE = 0; 2420 2421 // Ignore (and complain about) any excess parentheses. 2422 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2423 if (!Invalid) { 2424 S.Diag(Arg->getSourceRange().getBegin(), 2425 diag::err_template_arg_extra_parens) 2426 << Arg->getSourceRange(); 2427 Invalid = true; 2428 } 2429 2430 Arg = Parens->getSubExpr(); 2431 } 2432 2433 bool AddressTaken = false; 2434 SourceLocation AddrOpLoc; 2435 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2436 if (UnOp->getOpcode() == UnaryOperator::AddrOf) { 2437 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2438 AddressTaken = true; 2439 AddrOpLoc = UnOp->getOperatorLoc(); 2440 } 2441 } else 2442 DRE = dyn_cast<DeclRefExpr>(Arg); 2443 2444 if (!DRE) { 2445 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref) 2446 << Arg->getSourceRange(); 2447 S.Diag(Param->getLocation(), diag::note_template_param_here); 2448 return true; 2449 } 2450 2451 // Stop checking the precise nature of the argument if it is value dependent, 2452 // it should be checked when instantiated. 2453 if (Arg->isValueDependent()) { 2454 Converted = TemplateArgument(ArgIn->Retain()); 2455 return false; 2456 } 2457 2458 if (!isa<ValueDecl>(DRE->getDecl())) { 2459 S.Diag(Arg->getSourceRange().getBegin(), 2460 diag::err_template_arg_not_object_or_func_form) 2461 << Arg->getSourceRange(); 2462 S.Diag(Param->getLocation(), diag::note_template_param_here); 2463 return true; 2464 } 2465 2466 NamedDecl *Entity = 0; 2467 2468 // Cannot refer to non-static data members 2469 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) { 2470 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field) 2471 << Field << Arg->getSourceRange(); 2472 S.Diag(Param->getLocation(), diag::note_template_param_here); 2473 return true; 2474 } 2475 2476 // Cannot refer to non-static member functions 2477 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl())) 2478 if (!Method->isStatic()) { 2479 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method) 2480 << Method << Arg->getSourceRange(); 2481 S.Diag(Param->getLocation(), diag::note_template_param_here); 2482 return true; 2483 } 2484 2485 // Functions must have external linkage. 2486 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) { 2487 if (!isExternalLinkage(Func->getLinkage())) { 2488 S.Diag(Arg->getSourceRange().getBegin(), 2489 diag::err_template_arg_function_not_extern) 2490 << Func << Arg->getSourceRange(); 2491 S.Diag(Func->getLocation(), diag::note_template_arg_internal_object) 2492 << true; 2493 return true; 2494 } 2495 2496 // Okay: we've named a function with external linkage. 2497 Entity = Func; 2498 2499 // If the template parameter has pointer type, the function decays. 2500 if (ParamType->isPointerType() && !AddressTaken) 2501 ArgType = S.Context.getPointerType(Func->getType()); 2502 else if (AddressTaken && ParamType->isReferenceType()) { 2503 // If we originally had an address-of operator, but the 2504 // parameter has reference type, complain and (if things look 2505 // like they will work) drop the address-of operator. 2506 if (!S.Context.hasSameUnqualifiedType(Func->getType(), 2507 ParamType.getNonReferenceType())) { 2508 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2509 << ParamType; 2510 S.Diag(Param->getLocation(), diag::note_template_param_here); 2511 return true; 2512 } 2513 2514 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2515 << ParamType 2516 << FixItHint::CreateRemoval(AddrOpLoc); 2517 S.Diag(Param->getLocation(), diag::note_template_param_here); 2518 2519 ArgType = Func->getType(); 2520 } 2521 } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 2522 if (!isExternalLinkage(Var->getLinkage())) { 2523 S.Diag(Arg->getSourceRange().getBegin(), 2524 diag::err_template_arg_object_not_extern) 2525 << Var << Arg->getSourceRange(); 2526 S.Diag(Var->getLocation(), diag::note_template_arg_internal_object) 2527 << true; 2528 return true; 2529 } 2530 2531 // A value of reference type is not an object. 2532 if (Var->getType()->isReferenceType()) { 2533 S.Diag(Arg->getSourceRange().getBegin(), 2534 diag::err_template_arg_reference_var) 2535 << Var->getType() << Arg->getSourceRange(); 2536 S.Diag(Param->getLocation(), diag::note_template_param_here); 2537 return true; 2538 } 2539 2540 // Okay: we've named an object with external linkage 2541 Entity = Var; 2542 2543 // If the template parameter has pointer type, we must have taken 2544 // the address of this object. 2545 if (ParamType->isReferenceType()) { 2546 if (AddressTaken) { 2547 // If we originally had an address-of operator, but the 2548 // parameter has reference type, complain and (if things look 2549 // like they will work) drop the address-of operator. 2550 if (!S.Context.hasSameUnqualifiedType(Var->getType(), 2551 ParamType.getNonReferenceType())) { 2552 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2553 << ParamType; 2554 S.Diag(Param->getLocation(), diag::note_template_param_here); 2555 return true; 2556 } 2557 2558 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2559 << ParamType 2560 << FixItHint::CreateRemoval(AddrOpLoc); 2561 S.Diag(Param->getLocation(), diag::note_template_param_here); 2562 2563 ArgType = Var->getType(); 2564 } 2565 } else if (!AddressTaken && ParamType->isPointerType()) { 2566 if (Var->getType()->isArrayType()) { 2567 // Array-to-pointer decay. 2568 ArgType = S.Context.getArrayDecayedType(Var->getType()); 2569 } else { 2570 // If the template parameter has pointer type but the address of 2571 // this object was not taken, complain and (possibly) recover by 2572 // taking the address of the entity. 2573 ArgType = S.Context.getPointerType(Var->getType()); 2574 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) { 2575 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2576 << ParamType; 2577 S.Diag(Param->getLocation(), diag::note_template_param_here); 2578 return true; 2579 } 2580 2581 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2582 << ParamType 2583 << FixItHint::CreateInsertion(Arg->getLocStart(), "&"); 2584 2585 S.Diag(Param->getLocation(), diag::note_template_param_here); 2586 } 2587 } 2588 } else { 2589 // We found something else, but we don't know specifically what it is. 2590 S.Diag(Arg->getSourceRange().getBegin(), 2591 diag::err_template_arg_not_object_or_func) 2592 << Arg->getSourceRange(); 2593 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); 2594 return true; 2595 } 2596 2597 if (ParamType->isPointerType() && 2598 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() && 2599 S.IsQualificationConversion(ArgType, ParamType)) { 2600 // For pointer-to-object types, qualification conversions are 2601 // permitted. 2602 } else { 2603 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) { 2604 if (!ParamRef->getPointeeType()->isFunctionType()) { 2605 // C++ [temp.arg.nontype]p5b3: 2606 // For a non-type template-parameter of type reference to 2607 // object, no conversions apply. The type referred to by the 2608 // reference may be more cv-qualified than the (otherwise 2609 // identical) type of the template- argument. The 2610 // template-parameter is bound directly to the 2611 // template-argument, which shall be an lvalue. 2612 2613 // FIXME: Other qualifiers? 2614 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers(); 2615 unsigned ArgQuals = ArgType.getCVRQualifiers(); 2616 2617 if ((ParamQuals | ArgQuals) != ParamQuals) { 2618 S.Diag(Arg->getSourceRange().getBegin(), 2619 diag::err_template_arg_ref_bind_ignores_quals) 2620 << ParamType << Arg->getType() 2621 << Arg->getSourceRange(); 2622 S.Diag(Param->getLocation(), diag::note_template_param_here); 2623 return true; 2624 } 2625 } 2626 } 2627 2628 // At this point, the template argument refers to an object or 2629 // function with external linkage. We now need to check whether the 2630 // argument and parameter types are compatible. 2631 if (!S.Context.hasSameUnqualifiedType(ArgType, 2632 ParamType.getNonReferenceType())) { 2633 // We can't perform this conversion or binding. 2634 if (ParamType->isReferenceType()) 2635 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind) 2636 << ParamType << Arg->getType() << Arg->getSourceRange(); 2637 else 2638 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible) 2639 << Arg->getType() << ParamType << Arg->getSourceRange(); 2640 S.Diag(Param->getLocation(), diag::note_template_param_here); 2641 return true; 2642 } 2643 } 2644 2645 // Create the template argument. 2646 Converted = TemplateArgument(Entity->getCanonicalDecl()); 2647 S.MarkDeclarationReferenced(Arg->getLocStart(), Entity); 2648 return false; 2649} 2650 2651/// \brief Checks whether the given template argument is a pointer to 2652/// member constant according to C++ [temp.arg.nontype]p1. 2653bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, 2654 TemplateArgument &Converted) { 2655 bool Invalid = false; 2656 2657 // See through any implicit casts we added to fix the type. 2658 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2659 Arg = Cast->getSubExpr(); 2660 2661 // C++ [temp.arg.nontype]p1: 2662 // 2663 // A template-argument for a non-type, non-template 2664 // template-parameter shall be one of: [...] 2665 // 2666 // -- a pointer to member expressed as described in 5.3.1. 2667 DeclRefExpr *DRE = 0; 2668 2669 // Ignore (and complain about) any excess parentheses. 2670 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2671 if (!Invalid) { 2672 Diag(Arg->getSourceRange().getBegin(), 2673 diag::err_template_arg_extra_parens) 2674 << Arg->getSourceRange(); 2675 Invalid = true; 2676 } 2677 2678 Arg = Parens->getSubExpr(); 2679 } 2680 2681 // A pointer-to-member constant written &Class::member. 2682 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2683 if (UnOp->getOpcode() == UnaryOperator::AddrOf) { 2684 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2685 if (DRE && !DRE->getQualifier()) 2686 DRE = 0; 2687 } 2688 } 2689 // A constant of pointer-to-member type. 2690 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { 2691 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { 2692 if (VD->getType()->isMemberPointerType()) { 2693 if (isa<NonTypeTemplateParmDecl>(VD) || 2694 (isa<VarDecl>(VD) && 2695 Context.getCanonicalType(VD->getType()).isConstQualified())) { 2696 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2697 Converted = TemplateArgument(Arg->Retain()); 2698 else 2699 Converted = TemplateArgument(VD->getCanonicalDecl()); 2700 return Invalid; 2701 } 2702 } 2703 } 2704 2705 DRE = 0; 2706 } 2707 2708 if (!DRE) 2709 return Diag(Arg->getSourceRange().getBegin(), 2710 diag::err_template_arg_not_pointer_to_member_form) 2711 << Arg->getSourceRange(); 2712 2713 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { 2714 assert((isa<FieldDecl>(DRE->getDecl()) || 2715 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && 2716 "Only non-static member pointers can make it here"); 2717 2718 // Okay: this is the address of a non-static member, and therefore 2719 // a member pointer constant. 2720 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2721 Converted = TemplateArgument(Arg->Retain()); 2722 else 2723 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); 2724 return Invalid; 2725 } 2726 2727 // We found something else, but we don't know specifically what it is. 2728 Diag(Arg->getSourceRange().getBegin(), 2729 diag::err_template_arg_not_pointer_to_member_form) 2730 << Arg->getSourceRange(); 2731 Diag(DRE->getDecl()->getLocation(), 2732 diag::note_template_arg_refers_here); 2733 return true; 2734} 2735 2736/// \brief Check a template argument against its corresponding 2737/// non-type template parameter. 2738/// 2739/// This routine implements the semantics of C++ [temp.arg.nontype]. 2740/// It returns true if an error occurred, and false otherwise. \p 2741/// InstantiatedParamType is the type of the non-type template 2742/// parameter after it has been instantiated. 2743/// 2744/// If no error was detected, Converted receives the converted template argument. 2745bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, 2746 QualType InstantiatedParamType, Expr *&Arg, 2747 TemplateArgument &Converted, 2748 CheckTemplateArgumentKind CTAK) { 2749 SourceLocation StartLoc = Arg->getSourceRange().getBegin(); 2750 2751 // If either the parameter has a dependent type or the argument is 2752 // type-dependent, there's nothing we can check now. 2753 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { 2754 // FIXME: Produce a cloned, canonical expression? 2755 Converted = TemplateArgument(Arg); 2756 return false; 2757 } 2758 2759 // C++ [temp.arg.nontype]p5: 2760 // The following conversions are performed on each expression used 2761 // as a non-type template-argument. If a non-type 2762 // template-argument cannot be converted to the type of the 2763 // corresponding template-parameter then the program is 2764 // ill-formed. 2765 // 2766 // -- for a non-type template-parameter of integral or 2767 // enumeration type, integral promotions (4.5) and integral 2768 // conversions (4.7) are applied. 2769 QualType ParamType = InstantiatedParamType; 2770 QualType ArgType = Arg->getType(); 2771 if (ParamType->isIntegralType() || ParamType->isEnumeralType()) { 2772 // C++ [temp.arg.nontype]p1: 2773 // A template-argument for a non-type, non-template 2774 // template-parameter shall be one of: 2775 // 2776 // -- an integral constant-expression of integral or enumeration 2777 // type; or 2778 // -- the name of a non-type template-parameter; or 2779 SourceLocation NonConstantLoc; 2780 llvm::APSInt Value; 2781 if (!ArgType->isIntegralType() && !ArgType->isEnumeralType()) { 2782 Diag(Arg->getSourceRange().getBegin(), 2783 diag::err_template_arg_not_integral_or_enumeral) 2784 << ArgType << Arg->getSourceRange(); 2785 Diag(Param->getLocation(), diag::note_template_param_here); 2786 return true; 2787 } else if (!Arg->isValueDependent() && 2788 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) { 2789 Diag(NonConstantLoc, diag::err_template_arg_not_ice) 2790 << ArgType << Arg->getSourceRange(); 2791 return true; 2792 } 2793 2794 // From here on out, all we care about are the unqualified forms 2795 // of the parameter and argument types. 2796 ParamType = ParamType.getUnqualifiedType(); 2797 ArgType = ArgType.getUnqualifiedType(); 2798 2799 // Try to convert the argument to the parameter's type. 2800 if (Context.hasSameType(ParamType, ArgType)) { 2801 // Okay: no conversion necessary 2802 } else if (CTAK == CTAK_Deduced) { 2803 // C++ [temp.deduct.type]p17: 2804 // If, in the declaration of a function template with a non-type 2805 // template-parameter, the non-type template- parameter is used 2806 // in an expression in the function parameter-list and, if the 2807 // corresponding template-argument is deduced, the 2808 // template-argument type shall match the type of the 2809 // template-parameter exactly, except that a template-argument 2810 // deduced from an array bound may be of any integral type. 2811 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch) 2812 << ArgType << ParamType; 2813 Diag(Param->getLocation(), diag::note_template_param_here); 2814 return true; 2815 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || 2816 !ParamType->isEnumeralType()) { 2817 // This is an integral promotion or conversion. 2818 ImpCastExprToType(Arg, ParamType, CastExpr::CK_IntegralCast); 2819 } else { 2820 // We can't perform this conversion. 2821 Diag(Arg->getSourceRange().getBegin(), 2822 diag::err_template_arg_not_convertible) 2823 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2824 Diag(Param->getLocation(), diag::note_template_param_here); 2825 return true; 2826 } 2827 2828 QualType IntegerType = Context.getCanonicalType(ParamType); 2829 if (const EnumType *Enum = IntegerType->getAs<EnumType>()) 2830 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); 2831 2832 if (!Arg->isValueDependent()) { 2833 llvm::APSInt OldValue = Value; 2834 2835 // Coerce the template argument's value to the value it will have 2836 // based on the template parameter's type. 2837 unsigned AllowedBits = Context.getTypeSize(IntegerType); 2838 if (Value.getBitWidth() != AllowedBits) 2839 Value.extOrTrunc(AllowedBits); 2840 Value.setIsSigned(IntegerType->isSignedIntegerType()); 2841 2842 // Complain if an unsigned parameter received a negative value. 2843 if (IntegerType->isUnsignedIntegerType() 2844 && (OldValue.isSigned() && OldValue.isNegative())) { 2845 Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative) 2846 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2847 << Arg->getSourceRange(); 2848 Diag(Param->getLocation(), diag::note_template_param_here); 2849 } 2850 2851 // Complain if we overflowed the template parameter's type. 2852 unsigned RequiredBits; 2853 if (IntegerType->isUnsignedIntegerType()) 2854 RequiredBits = OldValue.getActiveBits(); 2855 else if (OldValue.isUnsigned()) 2856 RequiredBits = OldValue.getActiveBits() + 1; 2857 else 2858 RequiredBits = OldValue.getMinSignedBits(); 2859 if (RequiredBits > AllowedBits) { 2860 Diag(Arg->getSourceRange().getBegin(), 2861 diag::warn_template_arg_too_large) 2862 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2863 << Arg->getSourceRange(); 2864 Diag(Param->getLocation(), diag::note_template_param_here); 2865 } 2866 } 2867 2868 // Add the value of this argument to the list of converted 2869 // arguments. We use the bitwidth and signedness of the template 2870 // parameter. 2871 if (Arg->isValueDependent()) { 2872 // The argument is value-dependent. Create a new 2873 // TemplateArgument with the converted expression. 2874 Converted = TemplateArgument(Arg); 2875 return false; 2876 } 2877 2878 Converted = TemplateArgument(Value, 2879 ParamType->isEnumeralType() ? ParamType 2880 : IntegerType); 2881 return false; 2882 } 2883 2884 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction 2885 2886 // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion 2887 // from a template argument of type std::nullptr_t to a non-type 2888 // template parameter of type pointer to object, pointer to 2889 // function, or pointer-to-member, respectively. 2890 if (ArgType->isNullPtrType() && 2891 (ParamType->isPointerType() || ParamType->isMemberPointerType())) { 2892 Converted = TemplateArgument((NamedDecl *)0); 2893 return false; 2894 } 2895 2896 // Handle pointer-to-function, reference-to-function, and 2897 // pointer-to-member-function all in (roughly) the same way. 2898 if (// -- For a non-type template-parameter of type pointer to 2899 // function, only the function-to-pointer conversion (4.3) is 2900 // applied. If the template-argument represents a set of 2901 // overloaded functions (or a pointer to such), the matching 2902 // function is selected from the set (13.4). 2903 (ParamType->isPointerType() && 2904 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || 2905 // -- For a non-type template-parameter of type reference to 2906 // function, no conversions apply. If the template-argument 2907 // represents a set of overloaded functions, the matching 2908 // function is selected from the set (13.4). 2909 (ParamType->isReferenceType() && 2910 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || 2911 // -- For a non-type template-parameter of type pointer to 2912 // member function, no conversions apply. If the 2913 // template-argument represents a set of overloaded member 2914 // functions, the matching member function is selected from 2915 // the set (13.4). 2916 (ParamType->isMemberPointerType() && 2917 ParamType->getAs<MemberPointerType>()->getPointeeType() 2918 ->isFunctionType())) { 2919 2920 if (Arg->getType() == Context.OverloadTy) { 2921 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType, 2922 true, 2923 FoundResult)) { 2924 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2925 return true; 2926 2927 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2928 ArgType = Arg->getType(); 2929 } else 2930 return true; 2931 } 2932 2933 if (!ParamType->isMemberPointerType()) 2934 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2935 ParamType, 2936 Arg, Converted); 2937 2938 if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType())) { 2939 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp, 2940 Arg->isLvalue(Context) == Expr::LV_Valid); 2941 } else if (!Context.hasSameUnqualifiedType(ArgType, 2942 ParamType.getNonReferenceType())) { 2943 // We can't perform this conversion. 2944 Diag(Arg->getSourceRange().getBegin(), 2945 diag::err_template_arg_not_convertible) 2946 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2947 Diag(Param->getLocation(), diag::note_template_param_here); 2948 return true; 2949 } 2950 2951 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2952 } 2953 2954 if (ParamType->isPointerType()) { 2955 // -- for a non-type template-parameter of type pointer to 2956 // object, qualification conversions (4.4) and the 2957 // array-to-pointer conversion (4.2) are applied. 2958 // C++0x also allows a value of std::nullptr_t. 2959 assert(ParamType->getAs<PointerType>()->getPointeeType()->isObjectType() && 2960 "Only object pointers allowed here"); 2961 2962 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2963 ParamType, 2964 Arg, Converted); 2965 } 2966 2967 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { 2968 // -- For a non-type template-parameter of type reference to 2969 // object, no conversions apply. The type referred to by the 2970 // reference may be more cv-qualified than the (otherwise 2971 // identical) type of the template-argument. The 2972 // template-parameter is bound directly to the 2973 // template-argument, which must be an lvalue. 2974 assert(ParamRefType->getPointeeType()->isObjectType() && 2975 "Only object references allowed here"); 2976 2977 if (Arg->getType() == Context.OverloadTy) { 2978 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, 2979 ParamRefType->getPointeeType(), 2980 true, 2981 FoundResult)) { 2982 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2983 return true; 2984 2985 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2986 ArgType = Arg->getType(); 2987 } else 2988 return true; 2989 } 2990 2991 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2992 ParamType, 2993 Arg, Converted); 2994 } 2995 2996 // -- For a non-type template-parameter of type pointer to data 2997 // member, qualification conversions (4.4) are applied. 2998 assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); 2999 3000 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) { 3001 // Types match exactly: nothing more to do here. 3002 } else if (IsQualificationConversion(ArgType, ParamType)) { 3003 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp, 3004 Arg->isLvalue(Context) == Expr::LV_Valid); 3005 } else { 3006 // We can't perform this conversion. 3007 Diag(Arg->getSourceRange().getBegin(), 3008 diag::err_template_arg_not_convertible) 3009 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 3010 Diag(Param->getLocation(), diag::note_template_param_here); 3011 return true; 3012 } 3013 3014 return CheckTemplateArgumentPointerToMember(Arg, Converted); 3015} 3016 3017/// \brief Check a template argument against its corresponding 3018/// template template parameter. 3019/// 3020/// This routine implements the semantics of C++ [temp.arg.template]. 3021/// It returns true if an error occurred, and false otherwise. 3022bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, 3023 const TemplateArgumentLoc &Arg) { 3024 TemplateName Name = Arg.getArgument().getAsTemplate(); 3025 TemplateDecl *Template = Name.getAsTemplateDecl(); 3026 if (!Template) { 3027 // Any dependent template name is fine. 3028 assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); 3029 return false; 3030 } 3031 3032 // C++ [temp.arg.template]p1: 3033 // A template-argument for a template template-parameter shall be 3034 // the name of a class template, expressed as id-expression. Only 3035 // primary class templates are considered when matching the 3036 // template template argument with the corresponding parameter; 3037 // partial specializations are not considered even if their 3038 // parameter lists match that of the template template parameter. 3039 // 3040 // Note that we also allow template template parameters here, which 3041 // will happen when we are dealing with, e.g., class template 3042 // partial specializations. 3043 if (!isa<ClassTemplateDecl>(Template) && 3044 !isa<TemplateTemplateParmDecl>(Template)) { 3045 assert(isa<FunctionTemplateDecl>(Template) && 3046 "Only function templates are possible here"); 3047 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); 3048 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) 3049 << Template; 3050 } 3051 3052 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), 3053 Param->getTemplateParameters(), 3054 true, 3055 TPL_TemplateTemplateArgumentMatch, 3056 Arg.getLocation()); 3057} 3058 3059/// \brief Given a non-type template argument that refers to a 3060/// declaration and the type of its corresponding non-type template 3061/// parameter, produce an expression that properly refers to that 3062/// declaration. 3063Sema::OwningExprResult 3064Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg, 3065 QualType ParamType, 3066 SourceLocation Loc) { 3067 assert(Arg.getKind() == TemplateArgument::Declaration && 3068 "Only declaration template arguments permitted here"); 3069 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl()); 3070 3071 if (VD->getDeclContext()->isRecord() && 3072 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) { 3073 // If the value is a class member, we might have a pointer-to-member. 3074 // Determine whether the non-type template template parameter is of 3075 // pointer-to-member type. If so, we need to build an appropriate 3076 // expression for a pointer-to-member, since a "normal" DeclRefExpr 3077 // would refer to the member itself. 3078 if (ParamType->isMemberPointerType()) { 3079 QualType ClassType 3080 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext())); 3081 NestedNameSpecifier *Qualifier 3082 = NestedNameSpecifier::Create(Context, 0, false, ClassType.getTypePtr()); 3083 CXXScopeSpec SS; 3084 SS.setScopeRep(Qualifier); 3085 OwningExprResult RefExpr = BuildDeclRefExpr(VD, 3086 VD->getType().getNonReferenceType(), 3087 Loc, 3088 &SS); 3089 if (RefExpr.isInvalid()) 3090 return ExprError(); 3091 3092 RefExpr = CreateBuiltinUnaryOp(Loc, UnaryOperator::AddrOf, move(RefExpr)); 3093 3094 // We might need to perform a trailing qualification conversion, since 3095 // the element type on the parameter could be more qualified than the 3096 // element type in the expression we constructed. 3097 if (IsQualificationConversion(((Expr*) RefExpr.get())->getType(), 3098 ParamType.getUnqualifiedType())) { 3099 Expr *RefE = RefExpr.takeAs<Expr>(); 3100 ImpCastExprToType(RefE, ParamType.getUnqualifiedType(), 3101 CastExpr::CK_NoOp); 3102 RefExpr = Owned(RefE); 3103 } 3104 3105 assert(!RefExpr.isInvalid() && 3106 Context.hasSameType(((Expr*) RefExpr.get())->getType(), 3107 ParamType.getUnqualifiedType())); 3108 return move(RefExpr); 3109 } 3110 } 3111 3112 QualType T = VD->getType().getNonReferenceType(); 3113 if (ParamType->isPointerType()) { 3114 // When the non-type template parameter is a pointer, take the 3115 // address of the declaration. 3116 OwningExprResult RefExpr = BuildDeclRefExpr(VD, T, Loc); 3117 if (RefExpr.isInvalid()) 3118 return ExprError(); 3119 3120 if (T->isFunctionType() || T->isArrayType()) { 3121 // Decay functions and arrays. 3122 Expr *RefE = (Expr *)RefExpr.get(); 3123 DefaultFunctionArrayConversion(RefE); 3124 if (RefE != RefExpr.get()) { 3125 RefExpr.release(); 3126 RefExpr = Owned(RefE); 3127 } 3128 3129 return move(RefExpr); 3130 } 3131 3132 // Take the address of everything else 3133 return CreateBuiltinUnaryOp(Loc, UnaryOperator::AddrOf, move(RefExpr)); 3134 } 3135 3136 // If the non-type template parameter has reference type, qualify the 3137 // resulting declaration reference with the extra qualifiers on the 3138 // type that the reference refers to. 3139 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) 3140 T = Context.getQualifiedType(T, TargetRef->getPointeeType().getQualifiers()); 3141 3142 return BuildDeclRefExpr(VD, T, Loc); 3143} 3144 3145/// \brief Construct a new expression that refers to the given 3146/// integral template argument with the given source-location 3147/// information. 3148/// 3149/// This routine takes care of the mapping from an integral template 3150/// argument (which may have any integral type) to the appropriate 3151/// literal value. 3152Sema::OwningExprResult 3153Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg, 3154 SourceLocation Loc) { 3155 assert(Arg.getKind() == TemplateArgument::Integral && 3156 "Operation is only value for integral template arguments"); 3157 QualType T = Arg.getIntegralType(); 3158 if (T->isCharType() || T->isWideCharType()) 3159 return Owned(new (Context) CharacterLiteral( 3160 Arg.getAsIntegral()->getZExtValue(), 3161 T->isWideCharType(), 3162 T, 3163 Loc)); 3164 if (T->isBooleanType()) 3165 return Owned(new (Context) CXXBoolLiteralExpr( 3166 Arg.getAsIntegral()->getBoolValue(), 3167 T, 3168 Loc)); 3169 3170 return Owned(new (Context) IntegerLiteral(*Arg.getAsIntegral(), T, Loc)); 3171} 3172 3173 3174/// \brief Determine whether the given template parameter lists are 3175/// equivalent. 3176/// 3177/// \param New The new template parameter list, typically written in the 3178/// source code as part of a new template declaration. 3179/// 3180/// \param Old The old template parameter list, typically found via 3181/// name lookup of the template declared with this template parameter 3182/// list. 3183/// 3184/// \param Complain If true, this routine will produce a diagnostic if 3185/// the template parameter lists are not equivalent. 3186/// 3187/// \param Kind describes how we are to match the template parameter lists. 3188/// 3189/// \param TemplateArgLoc If this source location is valid, then we 3190/// are actually checking the template parameter list of a template 3191/// argument (New) against the template parameter list of its 3192/// corresponding template template parameter (Old). We produce 3193/// slightly different diagnostics in this scenario. 3194/// 3195/// \returns True if the template parameter lists are equal, false 3196/// otherwise. 3197bool 3198Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, 3199 TemplateParameterList *Old, 3200 bool Complain, 3201 TemplateParameterListEqualKind Kind, 3202 SourceLocation TemplateArgLoc) { 3203 if (Old->size() != New->size()) { 3204 if (Complain) { 3205 unsigned NextDiag = diag::err_template_param_list_different_arity; 3206 if (TemplateArgLoc.isValid()) { 3207 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3208 NextDiag = diag::note_template_param_list_different_arity; 3209 } 3210 Diag(New->getTemplateLoc(), NextDiag) 3211 << (New->size() > Old->size()) 3212 << (Kind != TPL_TemplateMatch) 3213 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); 3214 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) 3215 << (Kind != TPL_TemplateMatch) 3216 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); 3217 } 3218 3219 return false; 3220 } 3221 3222 for (TemplateParameterList::iterator OldParm = Old->begin(), 3223 OldParmEnd = Old->end(), NewParm = New->begin(); 3224 OldParm != OldParmEnd; ++OldParm, ++NewParm) { 3225 if ((*OldParm)->getKind() != (*NewParm)->getKind()) { 3226 if (Complain) { 3227 unsigned NextDiag = diag::err_template_param_different_kind; 3228 if (TemplateArgLoc.isValid()) { 3229 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3230 NextDiag = diag::note_template_param_different_kind; 3231 } 3232 Diag((*NewParm)->getLocation(), NextDiag) 3233 << (Kind != TPL_TemplateMatch); 3234 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration) 3235 << (Kind != TPL_TemplateMatch); 3236 } 3237 return false; 3238 } 3239 3240 if (TemplateTypeParmDecl *OldTTP 3241 = dyn_cast<TemplateTypeParmDecl>(*OldParm)) { 3242 // Template type parameters are equivalent if either both are template 3243 // type parameter packs or neither are (since we know we're at the same 3244 // index). 3245 TemplateTypeParmDecl *NewTTP = cast<TemplateTypeParmDecl>(*NewParm); 3246 if (OldTTP->isParameterPack() != NewTTP->isParameterPack()) { 3247 // FIXME: Implement the rules in C++0x [temp.arg.template]p5 that 3248 // allow one to match a template parameter pack in the template 3249 // parameter list of a template template parameter to one or more 3250 // template parameters in the template parameter list of the 3251 // corresponding template template argument. 3252 if (Complain) { 3253 unsigned NextDiag = diag::err_template_parameter_pack_non_pack; 3254 if (TemplateArgLoc.isValid()) { 3255 Diag(TemplateArgLoc, 3256 diag::err_template_arg_template_params_mismatch); 3257 NextDiag = diag::note_template_parameter_pack_non_pack; 3258 } 3259 Diag(NewTTP->getLocation(), NextDiag) 3260 << 0 << NewTTP->isParameterPack(); 3261 Diag(OldTTP->getLocation(), diag::note_template_parameter_pack_here) 3262 << 0 << OldTTP->isParameterPack(); 3263 } 3264 return false; 3265 } 3266 } else if (NonTypeTemplateParmDecl *OldNTTP 3267 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) { 3268 // The types of non-type template parameters must agree. 3269 NonTypeTemplateParmDecl *NewNTTP 3270 = cast<NonTypeTemplateParmDecl>(*NewParm); 3271 3272 // If we are matching a template template argument to a template 3273 // template parameter and one of the non-type template parameter types 3274 // is dependent, then we must wait until template instantiation time 3275 // to actually compare the arguments. 3276 if (Kind == TPL_TemplateTemplateArgumentMatch && 3277 (OldNTTP->getType()->isDependentType() || 3278 NewNTTP->getType()->isDependentType())) 3279 continue; 3280 3281 if (Context.getCanonicalType(OldNTTP->getType()) != 3282 Context.getCanonicalType(NewNTTP->getType())) { 3283 if (Complain) { 3284 unsigned NextDiag = diag::err_template_nontype_parm_different_type; 3285 if (TemplateArgLoc.isValid()) { 3286 Diag(TemplateArgLoc, 3287 diag::err_template_arg_template_params_mismatch); 3288 NextDiag = diag::note_template_nontype_parm_different_type; 3289 } 3290 Diag(NewNTTP->getLocation(), NextDiag) 3291 << NewNTTP->getType() 3292 << (Kind != TPL_TemplateMatch); 3293 Diag(OldNTTP->getLocation(), 3294 diag::note_template_nontype_parm_prev_declaration) 3295 << OldNTTP->getType(); 3296 } 3297 return false; 3298 } 3299 } else { 3300 // The template parameter lists of template template 3301 // parameters must agree. 3302 assert(isa<TemplateTemplateParmDecl>(*OldParm) && 3303 "Only template template parameters handled here"); 3304 TemplateTemplateParmDecl *OldTTP 3305 = cast<TemplateTemplateParmDecl>(*OldParm); 3306 TemplateTemplateParmDecl *NewTTP 3307 = cast<TemplateTemplateParmDecl>(*NewParm); 3308 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), 3309 OldTTP->getTemplateParameters(), 3310 Complain, 3311 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind), 3312 TemplateArgLoc)) 3313 return false; 3314 } 3315 } 3316 3317 return true; 3318} 3319 3320/// \brief Check whether a template can be declared within this scope. 3321/// 3322/// If the template declaration is valid in this scope, returns 3323/// false. Otherwise, issues a diagnostic and returns true. 3324bool 3325Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { 3326 // Find the nearest enclosing declaration scope. 3327 while ((S->getFlags() & Scope::DeclScope) == 0 || 3328 (S->getFlags() & Scope::TemplateParamScope) != 0) 3329 S = S->getParent(); 3330 3331 // C++ [temp]p2: 3332 // A template-declaration can appear only as a namespace scope or 3333 // class scope declaration. 3334 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 3335 if (Ctx && isa<LinkageSpecDecl>(Ctx) && 3336 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) 3337 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) 3338 << TemplateParams->getSourceRange(); 3339 3340 while (Ctx && isa<LinkageSpecDecl>(Ctx)) 3341 Ctx = Ctx->getParent(); 3342 3343 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) 3344 return false; 3345 3346 return Diag(TemplateParams->getTemplateLoc(), 3347 diag::err_template_outside_namespace_or_class_scope) 3348 << TemplateParams->getSourceRange(); 3349} 3350 3351/// \brief Determine what kind of template specialization the given declaration 3352/// is. 3353static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) { 3354 if (!D) 3355 return TSK_Undeclared; 3356 3357 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) 3358 return Record->getTemplateSpecializationKind(); 3359 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) 3360 return Function->getTemplateSpecializationKind(); 3361 if (VarDecl *Var = dyn_cast<VarDecl>(D)) 3362 return Var->getTemplateSpecializationKind(); 3363 3364 return TSK_Undeclared; 3365} 3366 3367/// \brief Check whether a specialization is well-formed in the current 3368/// context. 3369/// 3370/// This routine determines whether a template specialization can be declared 3371/// in the current context (C++ [temp.expl.spec]p2). 3372/// 3373/// \param S the semantic analysis object for which this check is being 3374/// performed. 3375/// 3376/// \param Specialized the entity being specialized or instantiated, which 3377/// may be a kind of template (class template, function template, etc.) or 3378/// a member of a class template (member function, static data member, 3379/// member class). 3380/// 3381/// \param PrevDecl the previous declaration of this entity, if any. 3382/// 3383/// \param Loc the location of the explicit specialization or instantiation of 3384/// this entity. 3385/// 3386/// \param IsPartialSpecialization whether this is a partial specialization of 3387/// a class template. 3388/// 3389/// \returns true if there was an error that we cannot recover from, false 3390/// otherwise. 3391static bool CheckTemplateSpecializationScope(Sema &S, 3392 NamedDecl *Specialized, 3393 NamedDecl *PrevDecl, 3394 SourceLocation Loc, 3395 bool IsPartialSpecialization) { 3396 // Keep these "kind" numbers in sync with the %select statements in the 3397 // various diagnostics emitted by this routine. 3398 int EntityKind = 0; 3399 bool isTemplateSpecialization = false; 3400 if (isa<ClassTemplateDecl>(Specialized)) { 3401 EntityKind = IsPartialSpecialization? 1 : 0; 3402 isTemplateSpecialization = true; 3403 } else if (isa<FunctionTemplateDecl>(Specialized)) { 3404 EntityKind = 2; 3405 isTemplateSpecialization = true; 3406 } else if (isa<CXXMethodDecl>(Specialized)) 3407 EntityKind = 3; 3408 else if (isa<VarDecl>(Specialized)) 3409 EntityKind = 4; 3410 else if (isa<RecordDecl>(Specialized)) 3411 EntityKind = 5; 3412 else { 3413 S.Diag(Loc, diag::err_template_spec_unknown_kind); 3414 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3415 return true; 3416 } 3417 3418 // C++ [temp.expl.spec]p2: 3419 // An explicit specialization shall be declared in the namespace 3420 // of which the template is a member, or, for member templates, in 3421 // the namespace of which the enclosing class or enclosing class 3422 // template is a member. An explicit specialization of a member 3423 // function, member class or static data member of a class 3424 // template shall be declared in the namespace of which the class 3425 // template is a member. Such a declaration may also be a 3426 // definition. If the declaration is not a definition, the 3427 // specialization may be defined later in the name- space in which 3428 // the explicit specialization was declared, or in a namespace 3429 // that encloses the one in which the explicit specialization was 3430 // declared. 3431 if (S.CurContext->getLookupContext()->isFunctionOrMethod()) { 3432 S.Diag(Loc, diag::err_template_spec_decl_function_scope) 3433 << Specialized; 3434 return true; 3435 } 3436 3437 if (S.CurContext->isRecord() && !IsPartialSpecialization) { 3438 S.Diag(Loc, diag::err_template_spec_decl_class_scope) 3439 << Specialized; 3440 return true; 3441 } 3442 3443 // C++ [temp.class.spec]p6: 3444 // A class template partial specialization may be declared or redeclared 3445 // in any namespace scope in which its definition may be defined (14.5.1 3446 // and 14.5.2). 3447 bool ComplainedAboutScope = false; 3448 DeclContext *SpecializedContext 3449 = Specialized->getDeclContext()->getEnclosingNamespaceContext(); 3450 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); 3451 if ((!PrevDecl || 3452 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || 3453 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ 3454 // There is no prior declaration of this entity, so this 3455 // specialization must be in the same context as the template 3456 // itself. 3457 if (!DC->Equals(SpecializedContext)) { 3458 if (isa<TranslationUnitDecl>(SpecializedContext)) 3459 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) 3460 << EntityKind << Specialized; 3461 else if (isa<NamespaceDecl>(SpecializedContext)) 3462 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope) 3463 << EntityKind << Specialized 3464 << cast<NamedDecl>(SpecializedContext); 3465 3466 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3467 ComplainedAboutScope = true; 3468 } 3469 } 3470 3471 // Make sure that this redeclaration (or definition) occurs in an enclosing 3472 // namespace. 3473 // Note that HandleDeclarator() performs this check for explicit 3474 // specializations of function templates, static data members, and member 3475 // functions, so we skip the check here for those kinds of entities. 3476 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. 3477 // Should we refactor that check, so that it occurs later? 3478 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && 3479 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || 3480 isa<FunctionDecl>(Specialized))) { 3481 if (isa<TranslationUnitDecl>(SpecializedContext)) 3482 S.Diag(Loc, diag::err_template_spec_redecl_global_scope) 3483 << EntityKind << Specialized; 3484 else if (isa<NamespaceDecl>(SpecializedContext)) 3485 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) 3486 << EntityKind << Specialized 3487 << cast<NamedDecl>(SpecializedContext); 3488 3489 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3490 } 3491 3492 // FIXME: check for specialization-after-instantiation errors and such. 3493 3494 return false; 3495} 3496 3497/// \brief Check the non-type template arguments of a class template 3498/// partial specialization according to C++ [temp.class.spec]p9. 3499/// 3500/// \param TemplateParams the template parameters of the primary class 3501/// template. 3502/// 3503/// \param TemplateArg the template arguments of the class template 3504/// partial specialization. 3505/// 3506/// \param MirrorsPrimaryTemplate will be set true if the class 3507/// template partial specialization arguments are identical to the 3508/// implicit template arguments of the primary template. This is not 3509/// necessarily an error (C++0x), and it is left to the caller to diagnose 3510/// this condition when it is an error. 3511/// 3512/// \returns true if there was an error, false otherwise. 3513bool Sema::CheckClassTemplatePartialSpecializationArgs( 3514 TemplateParameterList *TemplateParams, 3515 const TemplateArgumentListBuilder &TemplateArgs, 3516 bool &MirrorsPrimaryTemplate) { 3517 // FIXME: the interface to this function will have to change to 3518 // accommodate variadic templates. 3519 MirrorsPrimaryTemplate = true; 3520 3521 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments(); 3522 3523 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3524 // Determine whether the template argument list of the partial 3525 // specialization is identical to the implicit argument list of 3526 // the primary template. The caller may need to diagnostic this as 3527 // an error per C++ [temp.class.spec]p9b3. 3528 if (MirrorsPrimaryTemplate) { 3529 if (TemplateTypeParmDecl *TTP 3530 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) { 3531 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) != 3532 Context.getCanonicalType(ArgList[I].getAsType())) 3533 MirrorsPrimaryTemplate = false; 3534 } else if (TemplateTemplateParmDecl *TTP 3535 = dyn_cast<TemplateTemplateParmDecl>( 3536 TemplateParams->getParam(I))) { 3537 TemplateName Name = ArgList[I].getAsTemplate(); 3538 TemplateTemplateParmDecl *ArgDecl 3539 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()); 3540 if (!ArgDecl || 3541 ArgDecl->getIndex() != TTP->getIndex() || 3542 ArgDecl->getDepth() != TTP->getDepth()) 3543 MirrorsPrimaryTemplate = false; 3544 } 3545 } 3546 3547 NonTypeTemplateParmDecl *Param 3548 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); 3549 if (!Param) { 3550 continue; 3551 } 3552 3553 Expr *ArgExpr = ArgList[I].getAsExpr(); 3554 if (!ArgExpr) { 3555 MirrorsPrimaryTemplate = false; 3556 continue; 3557 } 3558 3559 // C++ [temp.class.spec]p8: 3560 // A non-type argument is non-specialized if it is the name of a 3561 // non-type parameter. All other non-type arguments are 3562 // specialized. 3563 // 3564 // Below, we check the two conditions that only apply to 3565 // specialized non-type arguments, so skip any non-specialized 3566 // arguments. 3567 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) 3568 if (NonTypeTemplateParmDecl *NTTP 3569 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) { 3570 if (MirrorsPrimaryTemplate && 3571 (Param->getIndex() != NTTP->getIndex() || 3572 Param->getDepth() != NTTP->getDepth())) 3573 MirrorsPrimaryTemplate = false; 3574 3575 continue; 3576 } 3577 3578 // C++ [temp.class.spec]p9: 3579 // Within the argument list of a class template partial 3580 // specialization, the following restrictions apply: 3581 // -- A partially specialized non-type argument expression 3582 // shall not involve a template parameter of the partial 3583 // specialization except when the argument expression is a 3584 // simple identifier. 3585 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { 3586 Diag(ArgExpr->getLocStart(), 3587 diag::err_dependent_non_type_arg_in_partial_spec) 3588 << ArgExpr->getSourceRange(); 3589 return true; 3590 } 3591 3592 // -- The type of a template parameter corresponding to a 3593 // specialized non-type argument shall not be dependent on a 3594 // parameter of the specialization. 3595 if (Param->getType()->isDependentType()) { 3596 Diag(ArgExpr->getLocStart(), 3597 diag::err_dependent_typed_non_type_arg_in_partial_spec) 3598 << Param->getType() 3599 << ArgExpr->getSourceRange(); 3600 Diag(Param->getLocation(), diag::note_template_param_here); 3601 return true; 3602 } 3603 3604 MirrorsPrimaryTemplate = false; 3605 } 3606 3607 return false; 3608} 3609 3610/// \brief Retrieve the previous declaration of the given declaration. 3611static NamedDecl *getPreviousDecl(NamedDecl *ND) { 3612 if (VarDecl *VD = dyn_cast<VarDecl>(ND)) 3613 return VD->getPreviousDeclaration(); 3614 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) 3615 return FD->getPreviousDeclaration(); 3616 if (TagDecl *TD = dyn_cast<TagDecl>(ND)) 3617 return TD->getPreviousDeclaration(); 3618 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND)) 3619 return TD->getPreviousDeclaration(); 3620 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND)) 3621 return FTD->getPreviousDeclaration(); 3622 if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND)) 3623 return CTD->getPreviousDeclaration(); 3624 return 0; 3625} 3626 3627Sema::DeclResult 3628Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, 3629 TagUseKind TUK, 3630 SourceLocation KWLoc, 3631 CXXScopeSpec &SS, 3632 TemplateTy TemplateD, 3633 SourceLocation TemplateNameLoc, 3634 SourceLocation LAngleLoc, 3635 ASTTemplateArgsPtr TemplateArgsIn, 3636 SourceLocation RAngleLoc, 3637 AttributeList *Attr, 3638 MultiTemplateParamsArg TemplateParameterLists) { 3639 assert(TUK != TUK_Reference && "References are not specializations"); 3640 3641 // Find the class template we're specializing 3642 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 3643 ClassTemplateDecl *ClassTemplate 3644 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); 3645 3646 if (!ClassTemplate) { 3647 Diag(TemplateNameLoc, diag::err_not_class_template_specialization) 3648 << (Name.getAsTemplateDecl() && 3649 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); 3650 return true; 3651 } 3652 3653 bool isExplicitSpecialization = false; 3654 bool isPartialSpecialization = false; 3655 3656 // Check the validity of the template headers that introduce this 3657 // template. 3658 // FIXME: We probably shouldn't complain about these headers for 3659 // friend declarations. 3660 TemplateParameterList *TemplateParams 3661 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS, 3662 (TemplateParameterList**)TemplateParameterLists.get(), 3663 TemplateParameterLists.size(), 3664 TUK == TUK_Friend, 3665 isExplicitSpecialization); 3666 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 3667 if (TemplateParams) 3668 --NumMatchedTemplateParamLists; 3669 3670 if (TemplateParams && TemplateParams->size() > 0) { 3671 isPartialSpecialization = true; 3672 3673 // C++ [temp.class.spec]p10: 3674 // The template parameter list of a specialization shall not 3675 // contain default template argument values. 3676 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3677 Decl *Param = TemplateParams->getParam(I); 3678 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { 3679 if (TTP->hasDefaultArgument()) { 3680 Diag(TTP->getDefaultArgumentLoc(), 3681 diag::err_default_arg_in_partial_spec); 3682 TTP->removeDefaultArgument(); 3683 } 3684 } else if (NonTypeTemplateParmDecl *NTTP 3685 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 3686 if (Expr *DefArg = NTTP->getDefaultArgument()) { 3687 Diag(NTTP->getDefaultArgumentLoc(), 3688 diag::err_default_arg_in_partial_spec) 3689 << DefArg->getSourceRange(); 3690 NTTP->removeDefaultArgument(); 3691 DefArg->Destroy(Context); 3692 } 3693 } else { 3694 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); 3695 if (TTP->hasDefaultArgument()) { 3696 Diag(TTP->getDefaultArgument().getLocation(), 3697 diag::err_default_arg_in_partial_spec) 3698 << TTP->getDefaultArgument().getSourceRange(); 3699 TTP->removeDefaultArgument(); 3700 } 3701 } 3702 } 3703 } else if (TemplateParams) { 3704 if (TUK == TUK_Friend) 3705 Diag(KWLoc, diag::err_template_spec_friend) 3706 << FixItHint::CreateRemoval( 3707 SourceRange(TemplateParams->getTemplateLoc(), 3708 TemplateParams->getRAngleLoc())) 3709 << SourceRange(LAngleLoc, RAngleLoc); 3710 else 3711 isExplicitSpecialization = true; 3712 } else if (TUK != TUK_Friend) { 3713 Diag(KWLoc, diag::err_template_spec_needs_header) 3714 << FixItHint::CreateInsertion(KWLoc, "template<> "); 3715 isExplicitSpecialization = true; 3716 } 3717 3718 // Check that the specialization uses the same tag kind as the 3719 // original template. 3720 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 3721 assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!"); 3722 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 3723 Kind, KWLoc, 3724 *ClassTemplate->getIdentifier())) { 3725 Diag(KWLoc, diag::err_use_with_wrong_tag) 3726 << ClassTemplate 3727 << FixItHint::CreateReplacement(KWLoc, 3728 ClassTemplate->getTemplatedDecl()->getKindName()); 3729 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 3730 diag::note_previous_use); 3731 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 3732 } 3733 3734 // Translate the parser's template argument list in our AST format. 3735 TemplateArgumentListInfo TemplateArgs; 3736 TemplateArgs.setLAngleLoc(LAngleLoc); 3737 TemplateArgs.setRAngleLoc(RAngleLoc); 3738 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 3739 3740 // Check that the template argument list is well-formed for this 3741 // template. 3742 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 3743 TemplateArgs.size()); 3744 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 3745 TemplateArgs, false, Converted)) 3746 return true; 3747 3748 assert((Converted.structuredSize() == 3749 ClassTemplate->getTemplateParameters()->size()) && 3750 "Converted template argument list is too short!"); 3751 3752 // Find the class template (partial) specialization declaration that 3753 // corresponds to these arguments. 3754 llvm::FoldingSetNodeID ID; 3755 if (isPartialSpecialization) { 3756 bool MirrorsPrimaryTemplate; 3757 if (CheckClassTemplatePartialSpecializationArgs( 3758 ClassTemplate->getTemplateParameters(), 3759 Converted, MirrorsPrimaryTemplate)) 3760 return true; 3761 3762 if (MirrorsPrimaryTemplate) { 3763 // C++ [temp.class.spec]p9b3: 3764 // 3765 // -- The argument list of the specialization shall not be identical 3766 // to the implicit argument list of the primary template. 3767 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) 3768 << (TUK == TUK_Definition) 3769 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc)); 3770 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, 3771 ClassTemplate->getIdentifier(), 3772 TemplateNameLoc, 3773 Attr, 3774 TemplateParams, 3775 AS_none); 3776 } 3777 3778 // FIXME: Diagnose friend partial specializations 3779 3780 if (!Name.isDependent() && 3781 !TemplateSpecializationType::anyDependentTemplateArguments( 3782 TemplateArgs.getArgumentArray(), 3783 TemplateArgs.size())) { 3784 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized) 3785 << ClassTemplate->getDeclName(); 3786 isPartialSpecialization = false; 3787 } else { 3788 // FIXME: Template parameter list matters, too 3789 ClassTemplatePartialSpecializationDecl::Profile(ID, 3790 Converted.getFlatArguments(), 3791 Converted.flatSize(), 3792 Context); 3793 } 3794 } 3795 3796 if (!isPartialSpecialization) 3797 ClassTemplateSpecializationDecl::Profile(ID, 3798 Converted.getFlatArguments(), 3799 Converted.flatSize(), 3800 Context); 3801 void *InsertPos = 0; 3802 ClassTemplateSpecializationDecl *PrevDecl = 0; 3803 3804 if (isPartialSpecialization) 3805 PrevDecl 3806 = ClassTemplate->getPartialSpecializations().FindNodeOrInsertPos(ID, 3807 InsertPos); 3808 else 3809 PrevDecl 3810 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 3811 3812 ClassTemplateSpecializationDecl *Specialization = 0; 3813 3814 // Check whether we can declare a class template specialization in 3815 // the current scope. 3816 if (TUK != TUK_Friend && 3817 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, 3818 TemplateNameLoc, 3819 isPartialSpecialization)) 3820 return true; 3821 3822 // The canonical type 3823 QualType CanonType; 3824 if (PrevDecl && 3825 (PrevDecl->getSpecializationKind() == TSK_Undeclared || 3826 TUK == TUK_Friend)) { 3827 // Since the only prior class template specialization with these 3828 // arguments was referenced but not declared, or we're only 3829 // referencing this specialization as a friend, reuse that 3830 // declaration node as our own, updating its source location to 3831 // reflect our new declaration. 3832 Specialization = PrevDecl; 3833 Specialization->setLocation(TemplateNameLoc); 3834 PrevDecl = 0; 3835 CanonType = Context.getTypeDeclType(Specialization); 3836 } else if (isPartialSpecialization) { 3837 // Build the canonical type that describes the converted template 3838 // arguments of the class template partial specialization. 3839 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); 3840 CanonType = Context.getTemplateSpecializationType(CanonTemplate, 3841 Converted.getFlatArguments(), 3842 Converted.flatSize()); 3843 3844 // Create a new class template partial specialization declaration node. 3845 ClassTemplatePartialSpecializationDecl *PrevPartial 3846 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); 3847 unsigned SequenceNumber = PrevPartial? PrevPartial->getSequenceNumber() 3848 : ClassTemplate->getPartialSpecializations().size(); 3849 ClassTemplatePartialSpecializationDecl *Partial 3850 = ClassTemplatePartialSpecializationDecl::Create(Context, Kind, 3851 ClassTemplate->getDeclContext(), 3852 TemplateNameLoc, 3853 TemplateParams, 3854 ClassTemplate, 3855 Converted, 3856 TemplateArgs, 3857 CanonType, 3858 PrevPartial, 3859 SequenceNumber); 3860 SetNestedNameSpecifier(Partial, SS); 3861 if (NumMatchedTemplateParamLists > 0) { 3862 Partial->setTemplateParameterListsInfo(NumMatchedTemplateParamLists, 3863 (TemplateParameterList**) TemplateParameterLists.release()); 3864 } 3865 3866 if (PrevPartial) { 3867 ClassTemplate->getPartialSpecializations().RemoveNode(PrevPartial); 3868 ClassTemplate->getPartialSpecializations().GetOrInsertNode(Partial); 3869 } else { 3870 ClassTemplate->getPartialSpecializations().InsertNode(Partial, InsertPos); 3871 } 3872 Specialization = Partial; 3873 3874 // If we are providing an explicit specialization of a member class 3875 // template specialization, make a note of that. 3876 if (PrevPartial && PrevPartial->getInstantiatedFromMember()) 3877 PrevPartial->setMemberSpecialization(); 3878 3879 // Check that all of the template parameters of the class template 3880 // partial specialization are deducible from the template 3881 // arguments. If not, this class template partial specialization 3882 // will never be used. 3883 llvm::SmallVector<bool, 8> DeducibleParams; 3884 DeducibleParams.resize(TemplateParams->size()); 3885 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true, 3886 TemplateParams->getDepth(), 3887 DeducibleParams); 3888 unsigned NumNonDeducible = 0; 3889 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) 3890 if (!DeducibleParams[I]) 3891 ++NumNonDeducible; 3892 3893 if (NumNonDeducible) { 3894 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible) 3895 << (NumNonDeducible > 1) 3896 << SourceRange(TemplateNameLoc, RAngleLoc); 3897 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) { 3898 if (!DeducibleParams[I]) { 3899 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I)); 3900 if (Param->getDeclName()) 3901 Diag(Param->getLocation(), 3902 diag::note_partial_spec_unused_parameter) 3903 << Param->getDeclName(); 3904 else 3905 Diag(Param->getLocation(), 3906 diag::note_partial_spec_unused_parameter) 3907 << std::string("<anonymous>"); 3908 } 3909 } 3910 } 3911 } else { 3912 // Create a new class template specialization declaration node for 3913 // this explicit specialization or friend declaration. 3914 Specialization 3915 = ClassTemplateSpecializationDecl::Create(Context, Kind, 3916 ClassTemplate->getDeclContext(), 3917 TemplateNameLoc, 3918 ClassTemplate, 3919 Converted, 3920 PrevDecl); 3921 SetNestedNameSpecifier(Specialization, SS); 3922 if (NumMatchedTemplateParamLists > 0) { 3923 Specialization->setTemplateParameterListsInfo( 3924 NumMatchedTemplateParamLists, 3925 (TemplateParameterList**) TemplateParameterLists.release()); 3926 } 3927 3928 if (PrevDecl) { 3929 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 3930 ClassTemplate->getSpecializations().GetOrInsertNode(Specialization); 3931 } else { 3932 ClassTemplate->getSpecializations().InsertNode(Specialization, 3933 InsertPos); 3934 } 3935 3936 CanonType = Context.getTypeDeclType(Specialization); 3937 } 3938 3939 // C++ [temp.expl.spec]p6: 3940 // If a template, a member template or the member of a class template is 3941 // explicitly specialized then that specialization shall be declared 3942 // before the first use of that specialization that would cause an implicit 3943 // instantiation to take place, in every translation unit in which such a 3944 // use occurs; no diagnostic is required. 3945 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { 3946 bool Okay = false; 3947 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 3948 // Is there any previous explicit specialization declaration? 3949 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) { 3950 Okay = true; 3951 break; 3952 } 3953 } 3954 3955 if (!Okay) { 3956 SourceRange Range(TemplateNameLoc, RAngleLoc); 3957 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) 3958 << Context.getTypeDeclType(Specialization) << Range; 3959 3960 Diag(PrevDecl->getPointOfInstantiation(), 3961 diag::note_instantiation_required_here) 3962 << (PrevDecl->getTemplateSpecializationKind() 3963 != TSK_ImplicitInstantiation); 3964 return true; 3965 } 3966 } 3967 3968 // If this is not a friend, note that this is an explicit specialization. 3969 if (TUK != TUK_Friend) 3970 Specialization->setSpecializationKind(TSK_ExplicitSpecialization); 3971 3972 // Check that this isn't a redefinition of this specialization. 3973 if (TUK == TUK_Definition) { 3974 if (RecordDecl *Def = Specialization->getDefinition()) { 3975 SourceRange Range(TemplateNameLoc, RAngleLoc); 3976 Diag(TemplateNameLoc, diag::err_redefinition) 3977 << Context.getTypeDeclType(Specialization) << Range; 3978 Diag(Def->getLocation(), diag::note_previous_definition); 3979 Specialization->setInvalidDecl(); 3980 return true; 3981 } 3982 } 3983 3984 // Build the fully-sugared type for this class template 3985 // specialization as the user wrote in the specialization 3986 // itself. This means that we'll pretty-print the type retrieved 3987 // from the specialization's declaration the way that the user 3988 // actually wrote the specialization, rather than formatting the 3989 // name based on the "canonical" representation used to store the 3990 // template arguments in the specialization. 3991 TypeSourceInfo *WrittenTy 3992 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 3993 TemplateArgs, CanonType); 3994 if (TUK != TUK_Friend) { 3995 Specialization->setTypeAsWritten(WrittenTy); 3996 Specialization->setTemplateKeywordLoc(KWLoc); 3997 } 3998 TemplateArgsIn.release(); 3999 4000 // C++ [temp.expl.spec]p9: 4001 // A template explicit specialization is in the scope of the 4002 // namespace in which the template was defined. 4003 // 4004 // We actually implement this paragraph where we set the semantic 4005 // context (in the creation of the ClassTemplateSpecializationDecl), 4006 // but we also maintain the lexical context where the actual 4007 // definition occurs. 4008 Specialization->setLexicalDeclContext(CurContext); 4009 4010 // We may be starting the definition of this specialization. 4011 if (TUK == TUK_Definition) 4012 Specialization->startDefinition(); 4013 4014 if (TUK == TUK_Friend) { 4015 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 4016 TemplateNameLoc, 4017 WrittenTy, 4018 /*FIXME:*/KWLoc); 4019 Friend->setAccess(AS_public); 4020 CurContext->addDecl(Friend); 4021 } else { 4022 // Add the specialization into its lexical context, so that it can 4023 // be seen when iterating through the list of declarations in that 4024 // context. However, specializations are not found by name lookup. 4025 CurContext->addDecl(Specialization); 4026 } 4027 return DeclPtrTy::make(Specialization); 4028} 4029 4030Sema::DeclPtrTy 4031Sema::ActOnTemplateDeclarator(Scope *S, 4032 MultiTemplateParamsArg TemplateParameterLists, 4033 Declarator &D) { 4034 return HandleDeclarator(S, D, move(TemplateParameterLists), false); 4035} 4036 4037Sema::DeclPtrTy 4038Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, 4039 MultiTemplateParamsArg TemplateParameterLists, 4040 Declarator &D) { 4041 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4042 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4043 "Not a function declarator!"); 4044 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4045 4046 if (FTI.hasPrototype) { 4047 // FIXME: Diagnose arguments without names in C. 4048 } 4049 4050 Scope *ParentScope = FnBodyScope->getParent(); 4051 4052 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4053 move(TemplateParameterLists), 4054 /*IsFunctionDefinition=*/true); 4055 if (FunctionTemplateDecl *FunctionTemplate 4056 = dyn_cast_or_null<FunctionTemplateDecl>(DP.getAs<Decl>())) 4057 return ActOnStartOfFunctionDef(FnBodyScope, 4058 DeclPtrTy::make(FunctionTemplate->getTemplatedDecl())); 4059 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP.getAs<Decl>())) 4060 return ActOnStartOfFunctionDef(FnBodyScope, DeclPtrTy::make(Function)); 4061 return DeclPtrTy(); 4062} 4063 4064/// \brief Strips various properties off an implicit instantiation 4065/// that has just been explicitly specialized. 4066static void StripImplicitInstantiation(NamedDecl *D) { 4067 D->invalidateAttrs(); 4068 4069 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 4070 FD->setInlineSpecified(false); 4071 } 4072} 4073 4074/// \brief Diagnose cases where we have an explicit template specialization 4075/// before/after an explicit template instantiation, producing diagnostics 4076/// for those cases where they are required and determining whether the 4077/// new specialization/instantiation will have any effect. 4078/// 4079/// \param NewLoc the location of the new explicit specialization or 4080/// instantiation. 4081/// 4082/// \param NewTSK the kind of the new explicit specialization or instantiation. 4083/// 4084/// \param PrevDecl the previous declaration of the entity. 4085/// 4086/// \param PrevTSK the kind of the old explicit specialization or instantiatin. 4087/// 4088/// \param PrevPointOfInstantiation if valid, indicates where the previus 4089/// declaration was instantiated (either implicitly or explicitly). 4090/// 4091/// \param HasNoEffect will be set to true to indicate that the new 4092/// specialization or instantiation has no effect and should be ignored. 4093/// 4094/// \returns true if there was an error that should prevent the introduction of 4095/// the new declaration into the AST, false otherwise. 4096bool 4097Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, 4098 TemplateSpecializationKind NewTSK, 4099 NamedDecl *PrevDecl, 4100 TemplateSpecializationKind PrevTSK, 4101 SourceLocation PrevPointOfInstantiation, 4102 bool &HasNoEffect) { 4103 HasNoEffect = false; 4104 4105 switch (NewTSK) { 4106 case TSK_Undeclared: 4107 case TSK_ImplicitInstantiation: 4108 assert(false && "Don't check implicit instantiations here"); 4109 return false; 4110 4111 case TSK_ExplicitSpecialization: 4112 switch (PrevTSK) { 4113 case TSK_Undeclared: 4114 case TSK_ExplicitSpecialization: 4115 // Okay, we're just specializing something that is either already 4116 // explicitly specialized or has merely been mentioned without any 4117 // instantiation. 4118 return false; 4119 4120 case TSK_ImplicitInstantiation: 4121 if (PrevPointOfInstantiation.isInvalid()) { 4122 // The declaration itself has not actually been instantiated, so it is 4123 // still okay to specialize it. 4124 StripImplicitInstantiation(PrevDecl); 4125 return false; 4126 } 4127 // Fall through 4128 4129 case TSK_ExplicitInstantiationDeclaration: 4130 case TSK_ExplicitInstantiationDefinition: 4131 assert((PrevTSK == TSK_ImplicitInstantiation || 4132 PrevPointOfInstantiation.isValid()) && 4133 "Explicit instantiation without point of instantiation?"); 4134 4135 // C++ [temp.expl.spec]p6: 4136 // If a template, a member template or the member of a class template 4137 // is explicitly specialized then that specialization shall be declared 4138 // before the first use of that specialization that would cause an 4139 // implicit instantiation to take place, in every translation unit in 4140 // which such a use occurs; no diagnostic is required. 4141 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 4142 // Is there any previous explicit specialization declaration? 4143 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) 4144 return false; 4145 } 4146 4147 Diag(NewLoc, diag::err_specialization_after_instantiation) 4148 << PrevDecl; 4149 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) 4150 << (PrevTSK != TSK_ImplicitInstantiation); 4151 4152 return true; 4153 } 4154 break; 4155 4156 case TSK_ExplicitInstantiationDeclaration: 4157 switch (PrevTSK) { 4158 case TSK_ExplicitInstantiationDeclaration: 4159 // This explicit instantiation declaration is redundant (that's okay). 4160 HasNoEffect = true; 4161 return false; 4162 4163 case TSK_Undeclared: 4164 case TSK_ImplicitInstantiation: 4165 // We're explicitly instantiating something that may have already been 4166 // implicitly instantiated; that's fine. 4167 return false; 4168 4169 case TSK_ExplicitSpecialization: 4170 // C++0x [temp.explicit]p4: 4171 // For a given set of template parameters, if an explicit instantiation 4172 // of a template appears after a declaration of an explicit 4173 // specialization for that template, the explicit instantiation has no 4174 // effect. 4175 HasNoEffect = true; 4176 return false; 4177 4178 case TSK_ExplicitInstantiationDefinition: 4179 // C++0x [temp.explicit]p10: 4180 // If an entity is the subject of both an explicit instantiation 4181 // declaration and an explicit instantiation definition in the same 4182 // translation unit, the definition shall follow the declaration. 4183 Diag(NewLoc, 4184 diag::err_explicit_instantiation_declaration_after_definition); 4185 Diag(PrevPointOfInstantiation, 4186 diag::note_explicit_instantiation_definition_here); 4187 assert(PrevPointOfInstantiation.isValid() && 4188 "Explicit instantiation without point of instantiation?"); 4189 HasNoEffect = true; 4190 return false; 4191 } 4192 break; 4193 4194 case TSK_ExplicitInstantiationDefinition: 4195 switch (PrevTSK) { 4196 case TSK_Undeclared: 4197 case TSK_ImplicitInstantiation: 4198 // We're explicitly instantiating something that may have already been 4199 // implicitly instantiated; that's fine. 4200 return false; 4201 4202 case TSK_ExplicitSpecialization: 4203 // C++ DR 259, C++0x [temp.explicit]p4: 4204 // For a given set of template parameters, if an explicit 4205 // instantiation of a template appears after a declaration of 4206 // an explicit specialization for that template, the explicit 4207 // instantiation has no effect. 4208 // 4209 // In C++98/03 mode, we only give an extension warning here, because it 4210 // is not harmful to try to explicitly instantiate something that 4211 // has been explicitly specialized. 4212 if (!getLangOptions().CPlusPlus0x) { 4213 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization) 4214 << PrevDecl; 4215 Diag(PrevDecl->getLocation(), 4216 diag::note_previous_template_specialization); 4217 } 4218 HasNoEffect = true; 4219 return false; 4220 4221 case TSK_ExplicitInstantiationDeclaration: 4222 // We're explicity instantiating a definition for something for which we 4223 // were previously asked to suppress instantiations. That's fine. 4224 return false; 4225 4226 case TSK_ExplicitInstantiationDefinition: 4227 // C++0x [temp.spec]p5: 4228 // For a given template and a given set of template-arguments, 4229 // - an explicit instantiation definition shall appear at most once 4230 // in a program, 4231 Diag(NewLoc, diag::err_explicit_instantiation_duplicate) 4232 << PrevDecl; 4233 Diag(PrevPointOfInstantiation, 4234 diag::note_previous_explicit_instantiation); 4235 HasNoEffect = true; 4236 return false; 4237 } 4238 break; 4239 } 4240 4241 assert(false && "Missing specialization/instantiation case?"); 4242 4243 return false; 4244} 4245 4246/// \brief Perform semantic analysis for the given dependent function 4247/// template specialization. The only possible way to get a dependent 4248/// function template specialization is with a friend declaration, 4249/// like so: 4250/// 4251/// template <class T> void foo(T); 4252/// template <class T> class A { 4253/// friend void foo<>(T); 4254/// }; 4255/// 4256/// There really isn't any useful analysis we can do here, so we 4257/// just store the information. 4258bool 4259Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD, 4260 const TemplateArgumentListInfo &ExplicitTemplateArgs, 4261 LookupResult &Previous) { 4262 // Remove anything from Previous that isn't a function template in 4263 // the correct context. 4264 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 4265 LookupResult::Filter F = Previous.makeFilter(); 4266 while (F.hasNext()) { 4267 NamedDecl *D = F.next()->getUnderlyingDecl(); 4268 if (!isa<FunctionTemplateDecl>(D) || 4269 !FDLookupContext->Equals(D->getDeclContext()->getLookupContext())) 4270 F.erase(); 4271 } 4272 F.done(); 4273 4274 // Should this be diagnosed here? 4275 if (Previous.empty()) return true; 4276 4277 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(), 4278 ExplicitTemplateArgs); 4279 return false; 4280} 4281 4282/// \brief Perform semantic analysis for the given function template 4283/// specialization. 4284/// 4285/// This routine performs all of the semantic analysis required for an 4286/// explicit function template specialization. On successful completion, 4287/// the function declaration \p FD will become a function template 4288/// specialization. 4289/// 4290/// \param FD the function declaration, which will be updated to become a 4291/// function template specialization. 4292/// 4293/// \param ExplicitTemplateArgs the explicitly-provided template arguments, 4294/// if any. Note that this may be valid info even when 0 arguments are 4295/// explicitly provided as in, e.g., \c void sort<>(char*, char*); 4296/// as it anyway contains info on the angle brackets locations. 4297/// 4298/// \param PrevDecl the set of declarations that may be specialized by 4299/// this function specialization. 4300bool 4301Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, 4302 const TemplateArgumentListInfo *ExplicitTemplateArgs, 4303 LookupResult &Previous) { 4304 // The set of function template specializations that could match this 4305 // explicit function template specialization. 4306 UnresolvedSet<8> Candidates; 4307 4308 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 4309 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4310 I != E; ++I) { 4311 NamedDecl *Ovl = (*I)->getUnderlyingDecl(); 4312 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { 4313 // Only consider templates found within the same semantic lookup scope as 4314 // FD. 4315 if (!FDLookupContext->Equals(Ovl->getDeclContext()->getLookupContext())) 4316 continue; 4317 4318 // C++ [temp.expl.spec]p11: 4319 // A trailing template-argument can be left unspecified in the 4320 // template-id naming an explicit function template specialization 4321 // provided it can be deduced from the function argument type. 4322 // Perform template argument deduction to determine whether we may be 4323 // specializing this template. 4324 // FIXME: It is somewhat wasteful to build 4325 TemplateDeductionInfo Info(Context, FD->getLocation()); 4326 FunctionDecl *Specialization = 0; 4327 if (TemplateDeductionResult TDK 4328 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, 4329 FD->getType(), 4330 Specialization, 4331 Info)) { 4332 // FIXME: Template argument deduction failed; record why it failed, so 4333 // that we can provide nifty diagnostics. 4334 (void)TDK; 4335 continue; 4336 } 4337 4338 // Record this candidate. 4339 Candidates.addDecl(Specialization, I.getAccess()); 4340 } 4341 } 4342 4343 // Find the most specialized function template. 4344 UnresolvedSetIterator Result 4345 = getMostSpecialized(Candidates.begin(), Candidates.end(), 4346 TPOC_Other, FD->getLocation(), 4347 PDiag(diag::err_function_template_spec_no_match) 4348 << FD->getDeclName(), 4349 PDiag(diag::err_function_template_spec_ambiguous) 4350 << FD->getDeclName() << (ExplicitTemplateArgs != 0), 4351 PDiag(diag::note_function_template_spec_matched)); 4352 if (Result == Candidates.end()) 4353 return true; 4354 4355 // Ignore access information; it doesn't figure into redeclaration checking. 4356 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 4357 Specialization->setLocation(FD->getLocation()); 4358 4359 // FIXME: Check if the prior specialization has a point of instantiation. 4360 // If so, we have run afoul of . 4361 4362 // If this is a friend declaration, then we're not really declaring 4363 // an explicit specialization. 4364 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None); 4365 4366 // Check the scope of this explicit specialization. 4367 if (!isFriend && 4368 CheckTemplateSpecializationScope(*this, 4369 Specialization->getPrimaryTemplate(), 4370 Specialization, FD->getLocation(), 4371 false)) 4372 return true; 4373 4374 // C++ [temp.expl.spec]p6: 4375 // If a template, a member template or the member of a class template is 4376 // explicitly specialized then that specialization shall be declared 4377 // before the first use of that specialization that would cause an implicit 4378 // instantiation to take place, in every translation unit in which such a 4379 // use occurs; no diagnostic is required. 4380 FunctionTemplateSpecializationInfo *SpecInfo 4381 = Specialization->getTemplateSpecializationInfo(); 4382 assert(SpecInfo && "Function template specialization info missing?"); 4383 4384 bool HasNoEffect = false; 4385 if (!isFriend && 4386 CheckSpecializationInstantiationRedecl(FD->getLocation(), 4387 TSK_ExplicitSpecialization, 4388 Specialization, 4389 SpecInfo->getTemplateSpecializationKind(), 4390 SpecInfo->getPointOfInstantiation(), 4391 HasNoEffect)) 4392 return true; 4393 4394 // Mark the prior declaration as an explicit specialization, so that later 4395 // clients know that this is an explicit specialization. 4396 if (!isFriend) 4397 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); 4398 4399 // Turn the given function declaration into a function template 4400 // specialization, with the template arguments from the previous 4401 // specialization. 4402 // Take copies of (semantic and syntactic) template argument lists. 4403 const TemplateArgumentList* TemplArgs = new (Context) 4404 TemplateArgumentList(Specialization->getTemplateSpecializationArgs()); 4405 const TemplateArgumentListInfo* TemplArgsAsWritten = ExplicitTemplateArgs 4406 ? new (Context) TemplateArgumentListInfo(*ExplicitTemplateArgs) : 0; 4407 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(), 4408 TemplArgs, /*InsertPos=*/0, 4409 SpecInfo->getTemplateSpecializationKind(), 4410 TemplArgsAsWritten); 4411 4412 // The "previous declaration" for this function template specialization is 4413 // the prior function template specialization. 4414 Previous.clear(); 4415 Previous.addDecl(Specialization); 4416 return false; 4417} 4418 4419/// \brief Perform semantic analysis for the given non-template member 4420/// specialization. 4421/// 4422/// This routine performs all of the semantic analysis required for an 4423/// explicit member function specialization. On successful completion, 4424/// the function declaration \p FD will become a member function 4425/// specialization. 4426/// 4427/// \param Member the member declaration, which will be updated to become a 4428/// specialization. 4429/// 4430/// \param Previous the set of declarations, one of which may be specialized 4431/// by this function specialization; the set will be modified to contain the 4432/// redeclared member. 4433bool 4434Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { 4435 assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); 4436 4437 // Try to find the member we are instantiating. 4438 NamedDecl *Instantiation = 0; 4439 NamedDecl *InstantiatedFrom = 0; 4440 MemberSpecializationInfo *MSInfo = 0; 4441 4442 if (Previous.empty()) { 4443 // Nowhere to look anyway. 4444 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { 4445 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4446 I != E; ++I) { 4447 NamedDecl *D = (*I)->getUnderlyingDecl(); 4448 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 4449 if (Context.hasSameType(Function->getType(), Method->getType())) { 4450 Instantiation = Method; 4451 InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); 4452 MSInfo = Method->getMemberSpecializationInfo(); 4453 break; 4454 } 4455 } 4456 } 4457 } else if (isa<VarDecl>(Member)) { 4458 VarDecl *PrevVar; 4459 if (Previous.isSingleResult() && 4460 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) 4461 if (PrevVar->isStaticDataMember()) { 4462 Instantiation = PrevVar; 4463 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); 4464 MSInfo = PrevVar->getMemberSpecializationInfo(); 4465 } 4466 } else if (isa<RecordDecl>(Member)) { 4467 CXXRecordDecl *PrevRecord; 4468 if (Previous.isSingleResult() && 4469 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { 4470 Instantiation = PrevRecord; 4471 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); 4472 MSInfo = PrevRecord->getMemberSpecializationInfo(); 4473 } 4474 } 4475 4476 if (!Instantiation) { 4477 // There is no previous declaration that matches. Since member 4478 // specializations are always out-of-line, the caller will complain about 4479 // this mismatch later. 4480 return false; 4481 } 4482 4483 // If this is a friend, just bail out here before we start turning 4484 // things into explicit specializations. 4485 if (Member->getFriendObjectKind() != Decl::FOK_None) { 4486 // Preserve instantiation information. 4487 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) { 4488 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction( 4489 cast<CXXMethodDecl>(InstantiatedFrom), 4490 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind()); 4491 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) { 4492 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4493 cast<CXXRecordDecl>(InstantiatedFrom), 4494 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind()); 4495 } 4496 4497 Previous.clear(); 4498 Previous.addDecl(Instantiation); 4499 return false; 4500 } 4501 4502 // Make sure that this is a specialization of a member. 4503 if (!InstantiatedFrom) { 4504 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) 4505 << Member; 4506 Diag(Instantiation->getLocation(), diag::note_specialized_decl); 4507 return true; 4508 } 4509 4510 // C++ [temp.expl.spec]p6: 4511 // If a template, a member template or the member of a class template is 4512 // explicitly specialized then that spe- cialization shall be declared 4513 // before the first use of that specialization that would cause an implicit 4514 // instantiation to take place, in every translation unit in which such a 4515 // use occurs; no diagnostic is required. 4516 assert(MSInfo && "Member specialization info missing?"); 4517 4518 bool HasNoEffect = false; 4519 if (CheckSpecializationInstantiationRedecl(Member->getLocation(), 4520 TSK_ExplicitSpecialization, 4521 Instantiation, 4522 MSInfo->getTemplateSpecializationKind(), 4523 MSInfo->getPointOfInstantiation(), 4524 HasNoEffect)) 4525 return true; 4526 4527 // Check the scope of this explicit specialization. 4528 if (CheckTemplateSpecializationScope(*this, 4529 InstantiatedFrom, 4530 Instantiation, Member->getLocation(), 4531 false)) 4532 return true; 4533 4534 // Note that this is an explicit instantiation of a member. 4535 // the original declaration to note that it is an explicit specialization 4536 // (if it was previously an implicit instantiation). This latter step 4537 // makes bookkeeping easier. 4538 if (isa<FunctionDecl>(Member)) { 4539 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); 4540 if (InstantiationFunction->getTemplateSpecializationKind() == 4541 TSK_ImplicitInstantiation) { 4542 InstantiationFunction->setTemplateSpecializationKind( 4543 TSK_ExplicitSpecialization); 4544 InstantiationFunction->setLocation(Member->getLocation()); 4545 } 4546 4547 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( 4548 cast<CXXMethodDecl>(InstantiatedFrom), 4549 TSK_ExplicitSpecialization); 4550 } else if (isa<VarDecl>(Member)) { 4551 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); 4552 if (InstantiationVar->getTemplateSpecializationKind() == 4553 TSK_ImplicitInstantiation) { 4554 InstantiationVar->setTemplateSpecializationKind( 4555 TSK_ExplicitSpecialization); 4556 InstantiationVar->setLocation(Member->getLocation()); 4557 } 4558 4559 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), 4560 cast<VarDecl>(InstantiatedFrom), 4561 TSK_ExplicitSpecialization); 4562 } else { 4563 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain"); 4564 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); 4565 if (InstantiationClass->getTemplateSpecializationKind() == 4566 TSK_ImplicitInstantiation) { 4567 InstantiationClass->setTemplateSpecializationKind( 4568 TSK_ExplicitSpecialization); 4569 InstantiationClass->setLocation(Member->getLocation()); 4570 } 4571 4572 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4573 cast<CXXRecordDecl>(InstantiatedFrom), 4574 TSK_ExplicitSpecialization); 4575 } 4576 4577 // Save the caller the trouble of having to figure out which declaration 4578 // this specialization matches. 4579 Previous.clear(); 4580 Previous.addDecl(Instantiation); 4581 return false; 4582} 4583 4584/// \brief Check the scope of an explicit instantiation. 4585static void CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, 4586 SourceLocation InstLoc, 4587 bool WasQualifiedName) { 4588 DeclContext *ExpectedContext 4589 = D->getDeclContext()->getEnclosingNamespaceContext()->getLookupContext(); 4590 DeclContext *CurContext = S.CurContext->getLookupContext(); 4591 4592 // C++0x [temp.explicit]p2: 4593 // An explicit instantiation shall appear in an enclosing namespace of its 4594 // template. 4595 // 4596 // This is DR275, which we do not retroactively apply to C++98/03. 4597 if (S.getLangOptions().CPlusPlus0x && 4598 !CurContext->Encloses(ExpectedContext)) { 4599 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(ExpectedContext)) 4600 S.Diag(InstLoc, 4601 S.getLangOptions().CPlusPlus0x? 4602 diag::err_explicit_instantiation_out_of_scope 4603 : diag::warn_explicit_instantiation_out_of_scope_0x) 4604 << D << NS; 4605 else 4606 S.Diag(InstLoc, 4607 S.getLangOptions().CPlusPlus0x? 4608 diag::err_explicit_instantiation_must_be_global 4609 : diag::warn_explicit_instantiation_out_of_scope_0x) 4610 << D; 4611 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4612 return; 4613 } 4614 4615 // C++0x [temp.explicit]p2: 4616 // If the name declared in the explicit instantiation is an unqualified 4617 // name, the explicit instantiation shall appear in the namespace where 4618 // its template is declared or, if that namespace is inline (7.3.1), any 4619 // namespace from its enclosing namespace set. 4620 if (WasQualifiedName) 4621 return; 4622 4623 if (CurContext->Equals(ExpectedContext)) 4624 return; 4625 4626 S.Diag(InstLoc, 4627 S.getLangOptions().CPlusPlus0x? 4628 diag::err_explicit_instantiation_unqualified_wrong_namespace 4629 : diag::warn_explicit_instantiation_unqualified_wrong_namespace_0x) 4630 << D << ExpectedContext; 4631 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4632} 4633 4634/// \brief Determine whether the given scope specifier has a template-id in it. 4635static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { 4636 if (!SS.isSet()) 4637 return false; 4638 4639 // C++0x [temp.explicit]p2: 4640 // If the explicit instantiation is for a member function, a member class 4641 // or a static data member of a class template specialization, the name of 4642 // the class template specialization in the qualified-id for the member 4643 // name shall be a simple-template-id. 4644 // 4645 // C++98 has the same restriction, just worded differently. 4646 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 4647 NNS; NNS = NNS->getPrefix()) 4648 if (Type *T = NNS->getAsType()) 4649 if (isa<TemplateSpecializationType>(T)) 4650 return true; 4651 4652 return false; 4653} 4654 4655// Explicit instantiation of a class template specialization 4656Sema::DeclResult 4657Sema::ActOnExplicitInstantiation(Scope *S, 4658 SourceLocation ExternLoc, 4659 SourceLocation TemplateLoc, 4660 unsigned TagSpec, 4661 SourceLocation KWLoc, 4662 const CXXScopeSpec &SS, 4663 TemplateTy TemplateD, 4664 SourceLocation TemplateNameLoc, 4665 SourceLocation LAngleLoc, 4666 ASTTemplateArgsPtr TemplateArgsIn, 4667 SourceLocation RAngleLoc, 4668 AttributeList *Attr) { 4669 // Find the class template we're specializing 4670 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 4671 ClassTemplateDecl *ClassTemplate 4672 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); 4673 4674 // Check that the specialization uses the same tag kind as the 4675 // original template. 4676 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 4677 assert(Kind != TTK_Enum && 4678 "Invalid enum tag in class template explicit instantiation!"); 4679 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 4680 Kind, KWLoc, 4681 *ClassTemplate->getIdentifier())) { 4682 Diag(KWLoc, diag::err_use_with_wrong_tag) 4683 << ClassTemplate 4684 << FixItHint::CreateReplacement(KWLoc, 4685 ClassTemplate->getTemplatedDecl()->getKindName()); 4686 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 4687 diag::note_previous_use); 4688 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 4689 } 4690 4691 // C++0x [temp.explicit]p2: 4692 // There are two forms of explicit instantiation: an explicit instantiation 4693 // definition and an explicit instantiation declaration. An explicit 4694 // instantiation declaration begins with the extern keyword. [...] 4695 TemplateSpecializationKind TSK 4696 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4697 : TSK_ExplicitInstantiationDeclaration; 4698 4699 // Translate the parser's template argument list in our AST format. 4700 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 4701 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 4702 4703 // Check that the template argument list is well-formed for this 4704 // template. 4705 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 4706 TemplateArgs.size()); 4707 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 4708 TemplateArgs, false, Converted)) 4709 return true; 4710 4711 assert((Converted.structuredSize() == 4712 ClassTemplate->getTemplateParameters()->size()) && 4713 "Converted template argument list is too short!"); 4714 4715 // Find the class template specialization declaration that 4716 // corresponds to these arguments. 4717 llvm::FoldingSetNodeID ID; 4718 ClassTemplateSpecializationDecl::Profile(ID, 4719 Converted.getFlatArguments(), 4720 Converted.flatSize(), 4721 Context); 4722 void *InsertPos = 0; 4723 ClassTemplateSpecializationDecl *PrevDecl 4724 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 4725 4726 TemplateSpecializationKind PrevDecl_TSK 4727 = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared; 4728 4729 // C++0x [temp.explicit]p2: 4730 // [...] An explicit instantiation shall appear in an enclosing 4731 // namespace of its template. [...] 4732 // 4733 // This is C++ DR 275. 4734 CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, 4735 SS.isSet()); 4736 4737 ClassTemplateSpecializationDecl *Specialization = 0; 4738 4739 bool ReusedDecl = false; 4740 bool HasNoEffect = false; 4741 if (PrevDecl) { 4742 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, 4743 PrevDecl, PrevDecl_TSK, 4744 PrevDecl->getPointOfInstantiation(), 4745 HasNoEffect)) 4746 return DeclPtrTy::make(PrevDecl); 4747 4748 // Even though HasNoEffect == true means that this explicit instantiation 4749 // has no effect on semantics, we go on to put its syntax in the AST. 4750 4751 if (PrevDecl_TSK == TSK_ImplicitInstantiation || 4752 PrevDecl_TSK == TSK_Undeclared) { 4753 // Since the only prior class template specialization with these 4754 // arguments was referenced but not declared, reuse that 4755 // declaration node as our own, updating the source location 4756 // for the template name to reflect our new declaration. 4757 // (Other source locations will be updated later.) 4758 Specialization = PrevDecl; 4759 Specialization->setLocation(TemplateNameLoc); 4760 PrevDecl = 0; 4761 ReusedDecl = true; 4762 } 4763 } 4764 4765 if (!Specialization) { 4766 // Create a new class template specialization declaration node for 4767 // this explicit specialization. 4768 Specialization 4769 = ClassTemplateSpecializationDecl::Create(Context, Kind, 4770 ClassTemplate->getDeclContext(), 4771 TemplateNameLoc, 4772 ClassTemplate, 4773 Converted, PrevDecl); 4774 SetNestedNameSpecifier(Specialization, SS); 4775 4776 if (!HasNoEffect) { 4777 if (PrevDecl) { 4778 // Remove the previous declaration from the folding set, since we want 4779 // to introduce a new declaration. 4780 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 4781 ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 4782 } 4783 // Insert the new specialization. 4784 ClassTemplate->getSpecializations().InsertNode(Specialization, InsertPos); 4785 } 4786 } 4787 4788 // Build the fully-sugared type for this explicit instantiation as 4789 // the user wrote in the explicit instantiation itself. This means 4790 // that we'll pretty-print the type retrieved from the 4791 // specialization's declaration the way that the user actually wrote 4792 // the explicit instantiation, rather than formatting the name based 4793 // on the "canonical" representation used to store the template 4794 // arguments in the specialization. 4795 TypeSourceInfo *WrittenTy 4796 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 4797 TemplateArgs, 4798 Context.getTypeDeclType(Specialization)); 4799 Specialization->setTypeAsWritten(WrittenTy); 4800 TemplateArgsIn.release(); 4801 4802 // Set source locations for keywords. 4803 Specialization->setExternLoc(ExternLoc); 4804 Specialization->setTemplateKeywordLoc(TemplateLoc); 4805 4806 // Add the explicit instantiation into its lexical context. However, 4807 // since explicit instantiations are never found by name lookup, we 4808 // just put it into the declaration context directly. 4809 Specialization->setLexicalDeclContext(CurContext); 4810 CurContext->addDecl(Specialization); 4811 4812 // Syntax is now OK, so return if it has no other effect on semantics. 4813 if (HasNoEffect) { 4814 // Set the template specialization kind. 4815 Specialization->setTemplateSpecializationKind(TSK); 4816 return DeclPtrTy::make(Specialization); 4817 } 4818 4819 // C++ [temp.explicit]p3: 4820 // A definition of a class template or class member template 4821 // shall be in scope at the point of the explicit instantiation of 4822 // the class template or class member template. 4823 // 4824 // This check comes when we actually try to perform the 4825 // instantiation. 4826 ClassTemplateSpecializationDecl *Def 4827 = cast_or_null<ClassTemplateSpecializationDecl>( 4828 Specialization->getDefinition()); 4829 if (!Def) 4830 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); 4831 else if (TSK == TSK_ExplicitInstantiationDefinition) { 4832 MarkVTableUsed(TemplateNameLoc, Specialization, true); 4833 Specialization->setPointOfInstantiation(Def->getPointOfInstantiation()); 4834 } 4835 4836 // Instantiate the members of this class template specialization. 4837 Def = cast_or_null<ClassTemplateSpecializationDecl>( 4838 Specialization->getDefinition()); 4839 if (Def) { 4840 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind(); 4841 4842 // Fix a TSK_ExplicitInstantiationDeclaration followed by a 4843 // TSK_ExplicitInstantiationDefinition 4844 if (Old_TSK == TSK_ExplicitInstantiationDeclaration && 4845 TSK == TSK_ExplicitInstantiationDefinition) 4846 Def->setTemplateSpecializationKind(TSK); 4847 4848 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); 4849 } 4850 4851 // Set the template specialization kind. 4852 Specialization->setTemplateSpecializationKind(TSK); 4853 return DeclPtrTy::make(Specialization); 4854} 4855 4856// Explicit instantiation of a member class of a class template. 4857Sema::DeclResult 4858Sema::ActOnExplicitInstantiation(Scope *S, 4859 SourceLocation ExternLoc, 4860 SourceLocation TemplateLoc, 4861 unsigned TagSpec, 4862 SourceLocation KWLoc, 4863 CXXScopeSpec &SS, 4864 IdentifierInfo *Name, 4865 SourceLocation NameLoc, 4866 AttributeList *Attr) { 4867 4868 bool Owned = false; 4869 bool IsDependent = false; 4870 DeclPtrTy TagD = ActOnTag(S, TagSpec, Action::TUK_Reference, 4871 KWLoc, SS, Name, NameLoc, Attr, AS_none, 4872 MultiTemplateParamsArg(*this, 0, 0), 4873 Owned, IsDependent); 4874 assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); 4875 4876 if (!TagD) 4877 return true; 4878 4879 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4880 if (Tag->isEnum()) { 4881 Diag(TemplateLoc, diag::err_explicit_instantiation_enum) 4882 << Context.getTypeDeclType(Tag); 4883 return true; 4884 } 4885 4886 if (Tag->isInvalidDecl()) 4887 return true; 4888 4889 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); 4890 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); 4891 if (!Pattern) { 4892 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) 4893 << Context.getTypeDeclType(Record); 4894 Diag(Record->getLocation(), diag::note_nontemplate_decl_here); 4895 return true; 4896 } 4897 4898 // C++0x [temp.explicit]p2: 4899 // If the explicit instantiation is for a class or member class, the 4900 // elaborated-type-specifier in the declaration shall include a 4901 // simple-template-id. 4902 // 4903 // C++98 has the same restriction, just worded differently. 4904 if (!ScopeSpecifierHasTemplateId(SS)) 4905 Diag(TemplateLoc, diag::err_explicit_instantiation_without_qualified_id) 4906 << Record << SS.getRange(); 4907 4908 // C++0x [temp.explicit]p2: 4909 // There are two forms of explicit instantiation: an explicit instantiation 4910 // definition and an explicit instantiation declaration. An explicit 4911 // instantiation declaration begins with the extern keyword. [...] 4912 TemplateSpecializationKind TSK 4913 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4914 : TSK_ExplicitInstantiationDeclaration; 4915 4916 // C++0x [temp.explicit]p2: 4917 // [...] An explicit instantiation shall appear in an enclosing 4918 // namespace of its template. [...] 4919 // 4920 // This is C++ DR 275. 4921 CheckExplicitInstantiationScope(*this, Record, NameLoc, true); 4922 4923 // Verify that it is okay to explicitly instantiate here. 4924 CXXRecordDecl *PrevDecl 4925 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration()); 4926 if (!PrevDecl && Record->getDefinition()) 4927 PrevDecl = Record; 4928 if (PrevDecl) { 4929 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); 4930 bool HasNoEffect = false; 4931 assert(MSInfo && "No member specialization information?"); 4932 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, 4933 PrevDecl, 4934 MSInfo->getTemplateSpecializationKind(), 4935 MSInfo->getPointOfInstantiation(), 4936 HasNoEffect)) 4937 return true; 4938 if (HasNoEffect) 4939 return TagD; 4940 } 4941 4942 CXXRecordDecl *RecordDef 4943 = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4944 if (!RecordDef) { 4945 // C++ [temp.explicit]p3: 4946 // A definition of a member class of a class template shall be in scope 4947 // at the point of an explicit instantiation of the member class. 4948 CXXRecordDecl *Def 4949 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition()); 4950 if (!Def) { 4951 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) 4952 << 0 << Record->getDeclName() << Record->getDeclContext(); 4953 Diag(Pattern->getLocation(), diag::note_forward_declaration) 4954 << Pattern; 4955 return true; 4956 } else { 4957 if (InstantiateClass(NameLoc, Record, Def, 4958 getTemplateInstantiationArgs(Record), 4959 TSK)) 4960 return true; 4961 4962 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4963 if (!RecordDef) 4964 return true; 4965 } 4966 } 4967 4968 // Instantiate all of the members of the class. 4969 InstantiateClassMembers(NameLoc, RecordDef, 4970 getTemplateInstantiationArgs(Record), TSK); 4971 4972 if (TSK == TSK_ExplicitInstantiationDefinition) 4973 MarkVTableUsed(NameLoc, RecordDef, true); 4974 4975 // FIXME: We don't have any representation for explicit instantiations of 4976 // member classes. Such a representation is not needed for compilation, but it 4977 // should be available for clients that want to see all of the declarations in 4978 // the source code. 4979 return TagD; 4980} 4981 4982Sema::DeclResult Sema::ActOnExplicitInstantiation(Scope *S, 4983 SourceLocation ExternLoc, 4984 SourceLocation TemplateLoc, 4985 Declarator &D) { 4986 // Explicit instantiations always require a name. 4987 DeclarationName Name = GetNameForDeclarator(D); 4988 if (!Name) { 4989 if (!D.isInvalidType()) 4990 Diag(D.getDeclSpec().getSourceRange().getBegin(), 4991 diag::err_explicit_instantiation_requires_name) 4992 << D.getDeclSpec().getSourceRange() 4993 << D.getSourceRange(); 4994 4995 return true; 4996 } 4997 4998 // The scope passed in may not be a decl scope. Zip up the scope tree until 4999 // we find one that is. 5000 while ((S->getFlags() & Scope::DeclScope) == 0 || 5001 (S->getFlags() & Scope::TemplateParamScope) != 0) 5002 S = S->getParent(); 5003 5004 // Determine the type of the declaration. 5005 TypeSourceInfo *T = GetTypeForDeclarator(D, S); 5006 QualType R = T->getType(); 5007 if (R.isNull()) 5008 return true; 5009 5010 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 5011 // Cannot explicitly instantiate a typedef. 5012 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) 5013 << Name; 5014 return true; 5015 } 5016 5017 // C++0x [temp.explicit]p1: 5018 // [...] An explicit instantiation of a function template shall not use the 5019 // inline or constexpr specifiers. 5020 // Presumably, this also applies to member functions of class templates as 5021 // well. 5022 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x) 5023 Diag(D.getDeclSpec().getInlineSpecLoc(), 5024 diag::err_explicit_instantiation_inline) 5025 <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 5026 5027 // FIXME: check for constexpr specifier. 5028 5029 // C++0x [temp.explicit]p2: 5030 // There are two forms of explicit instantiation: an explicit instantiation 5031 // definition and an explicit instantiation declaration. An explicit 5032 // instantiation declaration begins with the extern keyword. [...] 5033 TemplateSpecializationKind TSK 5034 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 5035 : TSK_ExplicitInstantiationDeclaration; 5036 5037 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName); 5038 LookupParsedName(Previous, S, &D.getCXXScopeSpec()); 5039 5040 if (!R->isFunctionType()) { 5041 // C++ [temp.explicit]p1: 5042 // A [...] static data member of a class template can be explicitly 5043 // instantiated from the member definition associated with its class 5044 // template. 5045 if (Previous.isAmbiguous()) 5046 return true; 5047 5048 VarDecl *Prev = Previous.getAsSingle<VarDecl>(); 5049 if (!Prev || !Prev->isStaticDataMember()) { 5050 // We expect to see a data data member here. 5051 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) 5052 << Name; 5053 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 5054 P != PEnd; ++P) 5055 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); 5056 return true; 5057 } 5058 5059 if (!Prev->getInstantiatedFromStaticDataMember()) { 5060 // FIXME: Check for explicit specialization? 5061 Diag(D.getIdentifierLoc(), 5062 diag::err_explicit_instantiation_data_member_not_instantiated) 5063 << Prev; 5064 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); 5065 // FIXME: Can we provide a note showing where this was declared? 5066 return true; 5067 } 5068 5069 // C++0x [temp.explicit]p2: 5070 // If the explicit instantiation is for a member function, a member class 5071 // or a static data member of a class template specialization, the name of 5072 // the class template specialization in the qualified-id for the member 5073 // name shall be a simple-template-id. 5074 // 5075 // C++98 has the same restriction, just worded differently. 5076 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5077 Diag(D.getIdentifierLoc(), 5078 diag::err_explicit_instantiation_without_qualified_id) 5079 << Prev << D.getCXXScopeSpec().getRange(); 5080 5081 // Check the scope of this explicit instantiation. 5082 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); 5083 5084 // Verify that it is okay to explicitly instantiate here. 5085 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); 5086 assert(MSInfo && "Missing static data member specialization info?"); 5087 bool HasNoEffect = false; 5088 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, 5089 MSInfo->getTemplateSpecializationKind(), 5090 MSInfo->getPointOfInstantiation(), 5091 HasNoEffect)) 5092 return true; 5093 if (HasNoEffect) 5094 return DeclPtrTy(); 5095 5096 // Instantiate static data member. 5097 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5098 if (TSK == TSK_ExplicitInstantiationDefinition) 5099 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev, false, 5100 /*DefinitionRequired=*/true); 5101 5102 // FIXME: Create an ExplicitInstantiation node? 5103 return DeclPtrTy(); 5104 } 5105 5106 // If the declarator is a template-id, translate the parser's template 5107 // argument list into our AST format. 5108 bool HasExplicitTemplateArgs = false; 5109 TemplateArgumentListInfo TemplateArgs; 5110 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 5111 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 5112 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 5113 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 5114 ASTTemplateArgsPtr TemplateArgsPtr(*this, 5115 TemplateId->getTemplateArgs(), 5116 TemplateId->NumArgs); 5117 translateTemplateArguments(TemplateArgsPtr, TemplateArgs); 5118 HasExplicitTemplateArgs = true; 5119 TemplateArgsPtr.release(); 5120 } 5121 5122 // C++ [temp.explicit]p1: 5123 // A [...] function [...] can be explicitly instantiated from its template. 5124 // A member function [...] of a class template can be explicitly 5125 // instantiated from the member definition associated with its class 5126 // template. 5127 UnresolvedSet<8> Matches; 5128 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 5129 P != PEnd; ++P) { 5130 NamedDecl *Prev = *P; 5131 if (!HasExplicitTemplateArgs) { 5132 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { 5133 if (Context.hasSameUnqualifiedType(Method->getType(), R)) { 5134 Matches.clear(); 5135 5136 Matches.addDecl(Method, P.getAccess()); 5137 if (Method->getTemplateSpecializationKind() == TSK_Undeclared) 5138 break; 5139 } 5140 } 5141 } 5142 5143 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); 5144 if (!FunTmpl) 5145 continue; 5146 5147 TemplateDeductionInfo Info(Context, D.getIdentifierLoc()); 5148 FunctionDecl *Specialization = 0; 5149 if (TemplateDeductionResult TDK 5150 = DeduceTemplateArguments(FunTmpl, 5151 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 5152 R, Specialization, Info)) { 5153 // FIXME: Keep track of almost-matches? 5154 (void)TDK; 5155 continue; 5156 } 5157 5158 Matches.addDecl(Specialization, P.getAccess()); 5159 } 5160 5161 // Find the most specialized function template specialization. 5162 UnresolvedSetIterator Result 5163 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, 5164 D.getIdentifierLoc(), 5165 PDiag(diag::err_explicit_instantiation_not_known) << Name, 5166 PDiag(diag::err_explicit_instantiation_ambiguous) << Name, 5167 PDiag(diag::note_explicit_instantiation_candidate)); 5168 5169 if (Result == Matches.end()) 5170 return true; 5171 5172 // Ignore access control bits, we don't need them for redeclaration checking. 5173 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 5174 5175 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { 5176 Diag(D.getIdentifierLoc(), 5177 diag::err_explicit_instantiation_member_function_not_instantiated) 5178 << Specialization 5179 << (Specialization->getTemplateSpecializationKind() == 5180 TSK_ExplicitSpecialization); 5181 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); 5182 return true; 5183 } 5184 5185 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration(); 5186 if (!PrevDecl && Specialization->isThisDeclarationADefinition()) 5187 PrevDecl = Specialization; 5188 5189 if (PrevDecl) { 5190 bool HasNoEffect = false; 5191 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, 5192 PrevDecl, 5193 PrevDecl->getTemplateSpecializationKind(), 5194 PrevDecl->getPointOfInstantiation(), 5195 HasNoEffect)) 5196 return true; 5197 5198 // FIXME: We may still want to build some representation of this 5199 // explicit specialization. 5200 if (HasNoEffect) 5201 return DeclPtrTy(); 5202 } 5203 5204 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5205 5206 if (TSK == TSK_ExplicitInstantiationDefinition) 5207 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization, 5208 false, /*DefinitionRequired=*/true); 5209 5210 // C++0x [temp.explicit]p2: 5211 // If the explicit instantiation is for a member function, a member class 5212 // or a static data member of a class template specialization, the name of 5213 // the class template specialization in the qualified-id for the member 5214 // name shall be a simple-template-id. 5215 // 5216 // C++98 has the same restriction, just worded differently. 5217 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); 5218 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && 5219 D.getCXXScopeSpec().isSet() && 5220 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5221 Diag(D.getIdentifierLoc(), 5222 diag::err_explicit_instantiation_without_qualified_id) 5223 << Specialization << D.getCXXScopeSpec().getRange(); 5224 5225 CheckExplicitInstantiationScope(*this, 5226 FunTmpl? (NamedDecl *)FunTmpl 5227 : Specialization->getInstantiatedFromMemberFunction(), 5228 D.getIdentifierLoc(), 5229 D.getCXXScopeSpec().isSet()); 5230 5231 // FIXME: Create some kind of ExplicitInstantiationDecl here. 5232 return DeclPtrTy(); 5233} 5234 5235Sema::TypeResult 5236Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5237 const CXXScopeSpec &SS, IdentifierInfo *Name, 5238 SourceLocation TagLoc, SourceLocation NameLoc) { 5239 // This has to hold, because SS is expected to be defined. 5240 assert(Name && "Expected a name in a dependent tag"); 5241 5242 NestedNameSpecifier *NNS 5243 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5244 if (!NNS) 5245 return true; 5246 5247 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5248 5249 if (TUK == TUK_Declaration || TUK == TUK_Definition) { 5250 Diag(NameLoc, diag::err_dependent_tag_decl) 5251 << (TUK == TUK_Definition) << Kind << SS.getRange(); 5252 return true; 5253 } 5254 5255 ElaboratedTypeKeyword Kwd = TypeWithKeyword::getKeywordForTagTypeKind(Kind); 5256 return Context.getDependentNameType(Kwd, NNS, Name).getAsOpaquePtr(); 5257} 5258 5259Sema::TypeResult 5260Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS, 5261 const IdentifierInfo &II, SourceLocation IdLoc) { 5262 NestedNameSpecifier *NNS 5263 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5264 if (!NNS) 5265 return true; 5266 5267 QualType T = CheckTypenameType(ETK_Typename, NNS, II, 5268 TypenameLoc, SS.getRange(), IdLoc); 5269 if (T.isNull()) 5270 return true; 5271 5272 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); 5273 if (isa<DependentNameType>(T)) { 5274 DependentNameTypeLoc TL = cast<DependentNameTypeLoc>(TSI->getTypeLoc()); 5275 TL.setKeywordLoc(TypenameLoc); 5276 TL.setQualifierRange(SS.getRange()); 5277 TL.setNameLoc(IdLoc); 5278 } else { 5279 ElaboratedTypeLoc TL = cast<ElaboratedTypeLoc>(TSI->getTypeLoc()); 5280 TL.setKeywordLoc(TypenameLoc); 5281 TL.setQualifierRange(SS.getRange()); 5282 cast<TypeSpecTypeLoc>(TL.getNamedTypeLoc()).setNameLoc(IdLoc); 5283 } 5284 5285 return CreateLocInfoType(T, TSI).getAsOpaquePtr(); 5286} 5287 5288Sema::TypeResult 5289Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS, 5290 SourceLocation TemplateLoc, TypeTy *Ty) { 5291 TypeSourceInfo *InnerTSI = 0; 5292 QualType T = GetTypeFromParser(Ty, &InnerTSI); 5293 NestedNameSpecifier *NNS 5294 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5295 5296 assert(isa<TemplateSpecializationType>(T) && 5297 "Expected a template specialization type"); 5298 5299 if (computeDeclContext(SS, false)) { 5300 // If we can compute a declaration context, then the "typename" 5301 // keyword was superfluous. Just build an ElaboratedType to keep 5302 // track of the nested-name-specifier. 5303 5304 // Push the inner type, preserving its source locations if possible. 5305 TypeLocBuilder Builder; 5306 if (InnerTSI) 5307 Builder.pushFullCopy(InnerTSI->getTypeLoc()); 5308 else 5309 Builder.push<TemplateSpecializationTypeLoc>(T).initialize(TemplateLoc); 5310 5311 T = Context.getElaboratedType(ETK_Typename, NNS, T); 5312 ElaboratedTypeLoc TL = Builder.push<ElaboratedTypeLoc>(T); 5313 TL.setKeywordLoc(TypenameLoc); 5314 TL.setQualifierRange(SS.getRange()); 5315 5316 TypeSourceInfo *TSI = Builder.getTypeSourceInfo(Context, T); 5317 return CreateLocInfoType(T, TSI).getAsOpaquePtr(); 5318 } 5319 5320 // TODO: it's really silly that we make a template specialization 5321 // type earlier only to drop it again here. 5322 TemplateSpecializationType *TST = cast<TemplateSpecializationType>(T); 5323 DependentTemplateName *DTN = 5324 TST->getTemplateName().getAsDependentTemplateName(); 5325 assert(DTN && "dependent template has non-dependent name?"); 5326 T = Context.getDependentTemplateSpecializationType(ETK_Typename, NNS, 5327 DTN->getIdentifier(), 5328 TST->getNumArgs(), 5329 TST->getArgs()); 5330 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T); 5331 DependentTemplateSpecializationTypeLoc TL = 5332 cast<DependentTemplateSpecializationTypeLoc>(TSI->getTypeLoc()); 5333 if (InnerTSI) { 5334 TemplateSpecializationTypeLoc TSTL = 5335 cast<TemplateSpecializationTypeLoc>(InnerTSI->getTypeLoc()); 5336 TL.setLAngleLoc(TSTL.getLAngleLoc()); 5337 TL.setRAngleLoc(TSTL.getRAngleLoc()); 5338 for (unsigned I = 0, E = TST->getNumArgs(); I != E; ++I) 5339 TL.setArgLocInfo(I, TSTL.getArgLocInfo(I)); 5340 } else { 5341 TL.initializeLocal(SourceLocation()); 5342 } 5343 TL.setKeywordLoc(TypenameLoc); 5344 TL.setQualifierRange(SS.getRange()); 5345 return CreateLocInfoType(T, TSI).getAsOpaquePtr(); 5346} 5347 5348/// \brief Build the type that describes a C++ typename specifier, 5349/// e.g., "typename T::type". 5350QualType 5351Sema::CheckTypenameType(ElaboratedTypeKeyword Keyword, 5352 NestedNameSpecifier *NNS, const IdentifierInfo &II, 5353 SourceLocation KeywordLoc, SourceRange NNSRange, 5354 SourceLocation IILoc) { 5355 CXXScopeSpec SS; 5356 SS.setScopeRep(NNS); 5357 SS.setRange(NNSRange); 5358 5359 DeclContext *Ctx = computeDeclContext(SS); 5360 if (!Ctx) { 5361 // If the nested-name-specifier is dependent and couldn't be 5362 // resolved to a type, build a typename type. 5363 assert(NNS->isDependent()); 5364 return Context.getDependentNameType(Keyword, NNS, &II); 5365 } 5366 5367 // If the nested-name-specifier refers to the current instantiation, 5368 // the "typename" keyword itself is superfluous. In C++03, the 5369 // program is actually ill-formed. However, DR 382 (in C++0x CD1) 5370 // allows such extraneous "typename" keywords, and we retroactively 5371 // apply this DR to C++03 code. In any case we continue. 5372 5373 if (RequireCompleteDeclContext(SS, Ctx)) 5374 return QualType(); 5375 5376 DeclarationName Name(&II); 5377 LookupResult Result(*this, Name, IILoc, LookupOrdinaryName); 5378 LookupQualifiedName(Result, Ctx); 5379 unsigned DiagID = 0; 5380 Decl *Referenced = 0; 5381 switch (Result.getResultKind()) { 5382 case LookupResult::NotFound: 5383 DiagID = diag::err_typename_nested_not_found; 5384 break; 5385 5386 case LookupResult::NotFoundInCurrentInstantiation: 5387 // Okay, it's a member of an unknown instantiation. 5388 return Context.getDependentNameType(Keyword, NNS, &II); 5389 5390 case LookupResult::Found: 5391 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { 5392 // We found a type. Build an ElaboratedType, since the 5393 // typename-specifier was just sugar. 5394 return Context.getElaboratedType(ETK_Typename, NNS, 5395 Context.getTypeDeclType(Type)); 5396 } 5397 5398 DiagID = diag::err_typename_nested_not_type; 5399 Referenced = Result.getFoundDecl(); 5400 break; 5401 5402 case LookupResult::FoundUnresolvedValue: 5403 llvm_unreachable("unresolved using decl in non-dependent context"); 5404 return QualType(); 5405 5406 case LookupResult::FoundOverloaded: 5407 DiagID = diag::err_typename_nested_not_type; 5408 Referenced = *Result.begin(); 5409 break; 5410 5411 case LookupResult::Ambiguous: 5412 return QualType(); 5413 } 5414 5415 // If we get here, it's because name lookup did not find a 5416 // type. Emit an appropriate diagnostic and return an error. 5417 SourceRange FullRange(KeywordLoc.isValid() ? KeywordLoc : NNSRange.getBegin(), 5418 IILoc); 5419 Diag(IILoc, DiagID) << FullRange << Name << Ctx; 5420 if (Referenced) 5421 Diag(Referenced->getLocation(), diag::note_typename_refers_here) 5422 << Name; 5423 return QualType(); 5424} 5425 5426namespace { 5427 // See Sema::RebuildTypeInCurrentInstantiation 5428 class CurrentInstantiationRebuilder 5429 : public TreeTransform<CurrentInstantiationRebuilder> { 5430 SourceLocation Loc; 5431 DeclarationName Entity; 5432 5433 public: 5434 typedef TreeTransform<CurrentInstantiationRebuilder> inherited; 5435 5436 CurrentInstantiationRebuilder(Sema &SemaRef, 5437 SourceLocation Loc, 5438 DeclarationName Entity) 5439 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), 5440 Loc(Loc), Entity(Entity) { } 5441 5442 /// \brief Determine whether the given type \p T has already been 5443 /// transformed. 5444 /// 5445 /// For the purposes of type reconstruction, a type has already been 5446 /// transformed if it is NULL or if it is not dependent. 5447 bool AlreadyTransformed(QualType T) { 5448 return T.isNull() || !T->isDependentType(); 5449 } 5450 5451 /// \brief Returns the location of the entity whose type is being 5452 /// rebuilt. 5453 SourceLocation getBaseLocation() { return Loc; } 5454 5455 /// \brief Returns the name of the entity whose type is being rebuilt. 5456 DeclarationName getBaseEntity() { return Entity; } 5457 5458 /// \brief Sets the "base" location and entity when that 5459 /// information is known based on another transformation. 5460 void setBase(SourceLocation Loc, DeclarationName Entity) { 5461 this->Loc = Loc; 5462 this->Entity = Entity; 5463 } 5464 5465 /// \brief Transforms an expression by returning the expression itself 5466 /// (an identity function). 5467 /// 5468 /// FIXME: This is completely unsafe; we will need to actually clone the 5469 /// expressions. 5470 Sema::OwningExprResult TransformExpr(Expr *E) { 5471 return getSema().Owned(E->Retain()); 5472 } 5473 }; 5474} 5475 5476/// \brief Rebuilds a type within the context of the current instantiation. 5477/// 5478/// The type \p T is part of the type of an out-of-line member definition of 5479/// a class template (or class template partial specialization) that was parsed 5480/// and constructed before we entered the scope of the class template (or 5481/// partial specialization thereof). This routine will rebuild that type now 5482/// that we have entered the declarator's scope, which may produce different 5483/// canonical types, e.g., 5484/// 5485/// \code 5486/// template<typename T> 5487/// struct X { 5488/// typedef T* pointer; 5489/// pointer data(); 5490/// }; 5491/// 5492/// template<typename T> 5493/// typename X<T>::pointer X<T>::data() { ... } 5494/// \endcode 5495/// 5496/// Here, the type "typename X<T>::pointer" will be created as a DependentNameType, 5497/// since we do not know that we can look into X<T> when we parsed the type. 5498/// This function will rebuild the type, performing the lookup of "pointer" 5499/// in X<T> and returning an ElaboratedType whose canonical type is the same 5500/// as the canonical type of T*, allowing the return types of the out-of-line 5501/// definition and the declaration to match. 5502TypeSourceInfo *Sema::RebuildTypeInCurrentInstantiation(TypeSourceInfo *T, 5503 SourceLocation Loc, 5504 DeclarationName Name) { 5505 if (!T || !T->getType()->isDependentType()) 5506 return T; 5507 5508 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); 5509 return Rebuilder.TransformType(T); 5510} 5511 5512bool Sema::RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS) { 5513 if (SS.isInvalid()) return true; 5514 5515 NestedNameSpecifier *NNS = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5516 CurrentInstantiationRebuilder Rebuilder(*this, SS.getRange().getBegin(), 5517 DeclarationName()); 5518 NestedNameSpecifier *Rebuilt = 5519 Rebuilder.TransformNestedNameSpecifier(NNS, SS.getRange()); 5520 if (!Rebuilt) return true; 5521 5522 SS.setScopeRep(Rebuilt); 5523 return false; 5524} 5525 5526/// \brief Produces a formatted string that describes the binding of 5527/// template parameters to template arguments. 5528std::string 5529Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5530 const TemplateArgumentList &Args) { 5531 // FIXME: For variadic templates, we'll need to get the structured list. 5532 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(), 5533 Args.flat_size()); 5534} 5535 5536std::string 5537Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5538 const TemplateArgument *Args, 5539 unsigned NumArgs) { 5540 std::string Result; 5541 5542 if (!Params || Params->size() == 0 || NumArgs == 0) 5543 return Result; 5544 5545 for (unsigned I = 0, N = Params->size(); I != N; ++I) { 5546 if (I >= NumArgs) 5547 break; 5548 5549 if (I == 0) 5550 Result += "[with "; 5551 else 5552 Result += ", "; 5553 5554 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { 5555 Result += Id->getName(); 5556 } else { 5557 Result += '$'; 5558 Result += llvm::utostr(I); 5559 } 5560 5561 Result += " = "; 5562 5563 switch (Args[I].getKind()) { 5564 case TemplateArgument::Null: 5565 Result += "<no value>"; 5566 break; 5567 5568 case TemplateArgument::Type: { 5569 std::string TypeStr; 5570 Args[I].getAsType().getAsStringInternal(TypeStr, 5571 Context.PrintingPolicy); 5572 Result += TypeStr; 5573 break; 5574 } 5575 5576 case TemplateArgument::Declaration: { 5577 bool Unnamed = true; 5578 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) { 5579 if (ND->getDeclName()) { 5580 Unnamed = false; 5581 Result += ND->getNameAsString(); 5582 } 5583 } 5584 5585 if (Unnamed) { 5586 Result += "<anonymous>"; 5587 } 5588 break; 5589 } 5590 5591 case TemplateArgument::Template: { 5592 std::string Str; 5593 llvm::raw_string_ostream OS(Str); 5594 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy); 5595 Result += OS.str(); 5596 break; 5597 } 5598 5599 case TemplateArgument::Integral: { 5600 Result += Args[I].getAsIntegral()->toString(10); 5601 break; 5602 } 5603 5604 case TemplateArgument::Expression: { 5605 // FIXME: This is non-optimal, since we're regurgitating the 5606 // expression we were given. 5607 std::string Str; 5608 { 5609 llvm::raw_string_ostream OS(Str); 5610 Args[I].getAsExpr()->printPretty(OS, Context, 0, 5611 Context.PrintingPolicy); 5612 } 5613 Result += Str; 5614 break; 5615 } 5616 5617 case TemplateArgument::Pack: 5618 // FIXME: Format template argument packs 5619 Result += "<template argument pack>"; 5620 break; 5621 } 5622 } 5623 5624 Result += ']'; 5625 return Result; 5626} 5627