SemaTemplate.cpp revision aaa095b2b1db8d4cbfe67eb7e94cb8343bc7de16
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/DeclTemplate.h" 19#include "clang/Parse/DeclSpec.h" 20#include "clang/Parse/Template.h" 21#include "clang/Basic/LangOptions.h" 22#include "clang/Basic/PartialDiagnostic.h" 23#include "llvm/ADT/StringExtras.h" 24using namespace clang; 25 26/// \brief Determine whether the declaration found is acceptable as the name 27/// of a template and, if so, return that template declaration. Otherwise, 28/// returns NULL. 29static NamedDecl *isAcceptableTemplateName(ASTContext &Context, NamedDecl *D) { 30 if (!D) 31 return 0; 32 33 if (isa<TemplateDecl>(D)) 34 return D; 35 36 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) { 37 // C++ [temp.local]p1: 38 // Like normal (non-template) classes, class templates have an 39 // injected-class-name (Clause 9). The injected-class-name 40 // can be used with or without a template-argument-list. When 41 // it is used without a template-argument-list, it is 42 // equivalent to the injected-class-name followed by the 43 // template-parameters of the class template enclosed in 44 // <>. When it is used with a template-argument-list, it 45 // refers to the specified class template specialization, 46 // which could be the current specialization or another 47 // specialization. 48 if (Record->isInjectedClassName()) { 49 Record = cast<CXXRecordDecl>(Record->getDeclContext()); 50 if (Record->getDescribedClassTemplate()) 51 return Record->getDescribedClassTemplate(); 52 53 if (ClassTemplateSpecializationDecl *Spec 54 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) 55 return Spec->getSpecializedTemplate(); 56 } 57 58 return 0; 59 } 60 61 return 0; 62} 63 64static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) { 65 LookupResult::Filter filter = R.makeFilter(); 66 while (filter.hasNext()) { 67 NamedDecl *Orig = filter.next(); 68 NamedDecl *Repl = isAcceptableTemplateName(C, Orig->getUnderlyingDecl()); 69 if (!Repl) 70 filter.erase(); 71 else if (Repl != Orig) 72 filter.replace(Repl); 73 } 74 filter.done(); 75} 76 77TemplateNameKind Sema::isTemplateName(Scope *S, 78 const CXXScopeSpec &SS, 79 UnqualifiedId &Name, 80 TypeTy *ObjectTypePtr, 81 bool EnteringContext, 82 TemplateTy &TemplateResult) { 83 DeclarationName TName; 84 85 switch (Name.getKind()) { 86 case UnqualifiedId::IK_Identifier: 87 TName = DeclarationName(Name.Identifier); 88 break; 89 90 case UnqualifiedId::IK_OperatorFunctionId: 91 TName = Context.DeclarationNames.getCXXOperatorName( 92 Name.OperatorFunctionId.Operator); 93 break; 94 95 case UnqualifiedId::IK_LiteralOperatorId: 96 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier); 97 break; 98 99 default: 100 return TNK_Non_template; 101 } 102 103 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 104 105 LookupResult R(*this, TName, SourceLocation(), LookupOrdinaryName); 106 R.suppressDiagnostics(); 107 LookupTemplateName(R, S, SS, ObjectType, EnteringContext); 108 if (R.empty()) 109 return TNK_Non_template; 110 111 TemplateName Template; 112 TemplateNameKind TemplateKind; 113 114 unsigned ResultCount = R.end() - R.begin(); 115 if (ResultCount > 1) { 116 // We assume that we'll preserve the qualifier from a function 117 // template name in other ways. 118 Template = Context.getOverloadedTemplateName(R.begin(), R.end()); 119 TemplateKind = TNK_Function_template; 120 } else { 121 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl()); 122 123 if (SS.isSet() && !SS.isInvalid()) { 124 NestedNameSpecifier *Qualifier 125 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 126 Template = Context.getQualifiedTemplateName(Qualifier, false, TD); 127 } else { 128 Template = TemplateName(TD); 129 } 130 131 if (isa<FunctionTemplateDecl>(TD)) 132 TemplateKind = TNK_Function_template; 133 else { 134 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD)); 135 TemplateKind = TNK_Type_template; 136 } 137 } 138 139 TemplateResult = TemplateTy::make(Template); 140 return TemplateKind; 141} 142 143void Sema::LookupTemplateName(LookupResult &Found, 144 Scope *S, const CXXScopeSpec &SS, 145 QualType ObjectType, 146 bool EnteringContext) { 147 // Determine where to perform name lookup 148 DeclContext *LookupCtx = 0; 149 bool isDependent = false; 150 if (!ObjectType.isNull()) { 151 // This nested-name-specifier occurs in a member access expression, e.g., 152 // x->B::f, and we are looking into the type of the object. 153 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 154 LookupCtx = computeDeclContext(ObjectType); 155 isDependent = ObjectType->isDependentType(); 156 assert((isDependent || !ObjectType->isIncompleteType()) && 157 "Caller should have completed object type"); 158 } else if (SS.isSet()) { 159 // This nested-name-specifier occurs after another nested-name-specifier, 160 // so long into the context associated with the prior nested-name-specifier. 161 LookupCtx = computeDeclContext(SS, EnteringContext); 162 isDependent = isDependentScopeSpecifier(SS); 163 164 // The declaration context must be complete. 165 if (LookupCtx && RequireCompleteDeclContext(SS)) 166 return; 167 } 168 169 bool ObjectTypeSearchedInScope = false; 170 if (LookupCtx) { 171 // Perform "qualified" name lookup into the declaration context we 172 // computed, which is either the type of the base of a member access 173 // expression or the declaration context associated with a prior 174 // nested-name-specifier. 175 LookupQualifiedName(Found, LookupCtx); 176 177 if (!ObjectType.isNull() && Found.empty()) { 178 // C++ [basic.lookup.classref]p1: 179 // In a class member access expression (5.2.5), if the . or -> token is 180 // immediately followed by an identifier followed by a <, the 181 // identifier must be looked up to determine whether the < is the 182 // beginning of a template argument list (14.2) or a less-than operator. 183 // The identifier is first looked up in the class of the object 184 // expression. If the identifier is not found, it is then looked up in 185 // the context of the entire postfix-expression and shall name a class 186 // or function template. 187 // 188 // FIXME: When we're instantiating a template, do we actually have to 189 // look in the scope of the template? Seems fishy... 190 if (S) LookupName(Found, S); 191 ObjectTypeSearchedInScope = true; 192 } 193 } else if (isDependent) { 194 // We cannot look into a dependent object type or 195 return; 196 } else { 197 // Perform unqualified name lookup in the current scope. 198 LookupName(Found, S); 199 } 200 201 // FIXME: Cope with ambiguous name-lookup results. 202 assert(!Found.isAmbiguous() && 203 "Cannot handle template name-lookup ambiguities"); 204 205 FilterAcceptableTemplateNames(Context, Found); 206 if (Found.empty()) 207 return; 208 209 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) { 210 // C++ [basic.lookup.classref]p1: 211 // [...] If the lookup in the class of the object expression finds a 212 // template, the name is also looked up in the context of the entire 213 // postfix-expression and [...] 214 // 215 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(), 216 LookupOrdinaryName); 217 LookupName(FoundOuter, S); 218 FilterAcceptableTemplateNames(Context, FoundOuter); 219 // FIXME: Handle ambiguities in this lookup better 220 221 if (FoundOuter.empty()) { 222 // - if the name is not found, the name found in the class of the 223 // object expression is used, otherwise 224 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) { 225 // - if the name is found in the context of the entire 226 // postfix-expression and does not name a class template, the name 227 // found in the class of the object expression is used, otherwise 228 } else { 229 // - if the name found is a class template, it must refer to the same 230 // entity as the one found in the class of the object expression, 231 // otherwise the program is ill-formed. 232 if (!Found.isSingleResult() || 233 Found.getFoundDecl()->getCanonicalDecl() 234 != FoundOuter.getFoundDecl()->getCanonicalDecl()) { 235 Diag(Found.getNameLoc(), 236 diag::err_nested_name_member_ref_lookup_ambiguous) 237 << Found.getLookupName(); 238 Diag(Found.getRepresentativeDecl()->getLocation(), 239 diag::note_ambig_member_ref_object_type) 240 << ObjectType; 241 Diag(FoundOuter.getFoundDecl()->getLocation(), 242 diag::note_ambig_member_ref_scope); 243 244 // Recover by taking the template that we found in the object 245 // expression's type. 246 } 247 } 248 } 249} 250 251/// ActOnDependentIdExpression - Handle a dependent id-expression that 252/// was just parsed. This is only possible with an explicit scope 253/// specifier naming a dependent type. 254Sema::OwningExprResult 255Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS, 256 DeclarationName Name, 257 SourceLocation NameLoc, 258 bool isAddressOfOperand, 259 const TemplateArgumentListInfo *TemplateArgs) { 260 NestedNameSpecifier *Qualifier 261 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 262 263 if (!isAddressOfOperand && 264 isa<CXXMethodDecl>(CurContext) && 265 cast<CXXMethodDecl>(CurContext)->isInstance()) { 266 QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context); 267 268 // Since the 'this' expression is synthesized, we don't need to 269 // perform the double-lookup check. 270 NamedDecl *FirstQualifierInScope = 0; 271 272 return Owned(CXXDependentScopeMemberExpr::Create(Context, 273 /*This*/ 0, ThisType, 274 /*IsArrow*/ true, 275 /*Op*/ SourceLocation(), 276 Qualifier, SS.getRange(), 277 FirstQualifierInScope, 278 Name, NameLoc, 279 TemplateArgs)); 280 } 281 282 return BuildDependentDeclRefExpr(SS, Name, NameLoc, TemplateArgs); 283} 284 285Sema::OwningExprResult 286Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS, 287 DeclarationName Name, 288 SourceLocation NameLoc, 289 const TemplateArgumentListInfo *TemplateArgs) { 290 return Owned(DependentScopeDeclRefExpr::Create(Context, 291 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 292 SS.getRange(), 293 Name, NameLoc, 294 TemplateArgs)); 295} 296 297/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining 298/// that the template parameter 'PrevDecl' is being shadowed by a new 299/// declaration at location Loc. Returns true to indicate that this is 300/// an error, and false otherwise. 301bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { 302 assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); 303 304 // Microsoft Visual C++ permits template parameters to be shadowed. 305 if (getLangOptions().Microsoft) 306 return false; 307 308 // C++ [temp.local]p4: 309 // A template-parameter shall not be redeclared within its 310 // scope (including nested scopes). 311 Diag(Loc, diag::err_template_param_shadow) 312 << cast<NamedDecl>(PrevDecl)->getDeclName(); 313 Diag(PrevDecl->getLocation(), diag::note_template_param_here); 314 return true; 315} 316 317/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset 318/// the parameter D to reference the templated declaration and return a pointer 319/// to the template declaration. Otherwise, do nothing to D and return null. 320TemplateDecl *Sema::AdjustDeclIfTemplate(DeclPtrTy &D) { 321 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D.getAs<Decl>())) { 322 D = DeclPtrTy::make(Temp->getTemplatedDecl()); 323 return Temp; 324 } 325 return 0; 326} 327 328static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, 329 const ParsedTemplateArgument &Arg) { 330 331 switch (Arg.getKind()) { 332 case ParsedTemplateArgument::Type: { 333 TypeSourceInfo *DI; 334 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); 335 if (!DI) 336 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation()); 337 return TemplateArgumentLoc(TemplateArgument(T), DI); 338 } 339 340 case ParsedTemplateArgument::NonType: { 341 Expr *E = static_cast<Expr *>(Arg.getAsExpr()); 342 return TemplateArgumentLoc(TemplateArgument(E), E); 343 } 344 345 case ParsedTemplateArgument::Template: { 346 TemplateName Template 347 = TemplateName::getFromVoidPointer(Arg.getAsTemplate().get()); 348 return TemplateArgumentLoc(TemplateArgument(Template), 349 Arg.getScopeSpec().getRange(), 350 Arg.getLocation()); 351 } 352 } 353 354 llvm_unreachable("Unhandled parsed template argument"); 355 return TemplateArgumentLoc(); 356} 357 358/// \brief Translates template arguments as provided by the parser 359/// into template arguments used by semantic analysis. 360void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn, 361 TemplateArgumentListInfo &TemplateArgs) { 362 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) 363 TemplateArgs.addArgument(translateTemplateArgument(*this, 364 TemplateArgsIn[I])); 365} 366 367/// ActOnTypeParameter - Called when a C++ template type parameter 368/// (e.g., "typename T") has been parsed. Typename specifies whether 369/// the keyword "typename" was used to declare the type parameter 370/// (otherwise, "class" was used), and KeyLoc is the location of the 371/// "class" or "typename" keyword. ParamName is the name of the 372/// parameter (NULL indicates an unnamed template parameter) and 373/// ParamName is the location of the parameter name (if any). 374/// If the type parameter has a default argument, it will be added 375/// later via ActOnTypeParameterDefault. 376Sema::DeclPtrTy Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, 377 SourceLocation EllipsisLoc, 378 SourceLocation KeyLoc, 379 IdentifierInfo *ParamName, 380 SourceLocation ParamNameLoc, 381 unsigned Depth, unsigned Position) { 382 assert(S->isTemplateParamScope() && 383 "Template type parameter not in template parameter scope!"); 384 bool Invalid = false; 385 386 if (ParamName) { 387 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, LookupTagName); 388 if (PrevDecl && PrevDecl->isTemplateParameter()) 389 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc, 390 PrevDecl); 391 } 392 393 SourceLocation Loc = ParamNameLoc; 394 if (!ParamName) 395 Loc = KeyLoc; 396 397 TemplateTypeParmDecl *Param 398 = TemplateTypeParmDecl::Create(Context, CurContext, Loc, 399 Depth, Position, ParamName, Typename, 400 Ellipsis); 401 if (Invalid) 402 Param->setInvalidDecl(); 403 404 if (ParamName) { 405 // Add the template parameter into the current scope. 406 S->AddDecl(DeclPtrTy::make(Param)); 407 IdResolver.AddDecl(Param); 408 } 409 410 return DeclPtrTy::make(Param); 411} 412 413/// ActOnTypeParameterDefault - Adds a default argument (the type 414/// Default) to the given template type parameter (TypeParam). 415void Sema::ActOnTypeParameterDefault(DeclPtrTy TypeParam, 416 SourceLocation EqualLoc, 417 SourceLocation DefaultLoc, 418 TypeTy *DefaultT) { 419 TemplateTypeParmDecl *Parm 420 = cast<TemplateTypeParmDecl>(TypeParam.getAs<Decl>()); 421 422 TypeSourceInfo *DefaultTInfo; 423 GetTypeFromParser(DefaultT, &DefaultTInfo); 424 425 assert(DefaultTInfo && "expected source information for type"); 426 427 // C++0x [temp.param]p9: 428 // A default template-argument may be specified for any kind of 429 // template-parameter that is not a template parameter pack. 430 if (Parm->isParameterPack()) { 431 Diag(DefaultLoc, diag::err_template_param_pack_default_arg); 432 return; 433 } 434 435 // C++ [temp.param]p14: 436 // A template-parameter shall not be used in its own default argument. 437 // FIXME: Implement this check! Needs a recursive walk over the types. 438 439 // Check the template argument itself. 440 if (CheckTemplateArgument(Parm, DefaultTInfo)) { 441 Parm->setInvalidDecl(); 442 return; 443 } 444 445 Parm->setDefaultArgument(DefaultTInfo, false); 446} 447 448/// \brief Check that the type of a non-type template parameter is 449/// well-formed. 450/// 451/// \returns the (possibly-promoted) parameter type if valid; 452/// otherwise, produces a diagnostic and returns a NULL type. 453QualType 454Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { 455 // C++ [temp.param]p4: 456 // 457 // A non-type template-parameter shall have one of the following 458 // (optionally cv-qualified) types: 459 // 460 // -- integral or enumeration type, 461 if (T->isIntegralType() || T->isEnumeralType() || 462 // -- pointer to object or pointer to function, 463 (T->isPointerType() && 464 (T->getAs<PointerType>()->getPointeeType()->isObjectType() || 465 T->getAs<PointerType>()->getPointeeType()->isFunctionType())) || 466 // -- reference to object or reference to function, 467 T->isReferenceType() || 468 // -- pointer to member. 469 T->isMemberPointerType() || 470 // If T is a dependent type, we can't do the check now, so we 471 // assume that it is well-formed. 472 T->isDependentType()) 473 return T; 474 // C++ [temp.param]p8: 475 // 476 // A non-type template-parameter of type "array of T" or 477 // "function returning T" is adjusted to be of type "pointer to 478 // T" or "pointer to function returning T", respectively. 479 else if (T->isArrayType()) 480 // FIXME: Keep the type prior to promotion? 481 return Context.getArrayDecayedType(T); 482 else if (T->isFunctionType()) 483 // FIXME: Keep the type prior to promotion? 484 return Context.getPointerType(T); 485 486 Diag(Loc, diag::err_template_nontype_parm_bad_type) 487 << T; 488 489 return QualType(); 490} 491 492/// ActOnNonTypeTemplateParameter - Called when a C++ non-type 493/// template parameter (e.g., "int Size" in "template<int Size> 494/// class Array") has been parsed. S is the current scope and D is 495/// the parsed declarator. 496Sema::DeclPtrTy Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, 497 unsigned Depth, 498 unsigned Position) { 499 TypeSourceInfo *TInfo = 0; 500 QualType T = GetTypeForDeclarator(D, S, &TInfo); 501 502 assert(S->isTemplateParamScope() && 503 "Non-type template parameter not in template parameter scope!"); 504 bool Invalid = false; 505 506 IdentifierInfo *ParamName = D.getIdentifier(); 507 if (ParamName) { 508 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, LookupTagName); 509 if (PrevDecl && PrevDecl->isTemplateParameter()) 510 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 511 PrevDecl); 512 } 513 514 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); 515 if (T.isNull()) { 516 T = Context.IntTy; // Recover with an 'int' type. 517 Invalid = true; 518 } 519 520 NonTypeTemplateParmDecl *Param 521 = NonTypeTemplateParmDecl::Create(Context, CurContext, D.getIdentifierLoc(), 522 Depth, Position, ParamName, T, TInfo); 523 if (Invalid) 524 Param->setInvalidDecl(); 525 526 if (D.getIdentifier()) { 527 // Add the template parameter into the current scope. 528 S->AddDecl(DeclPtrTy::make(Param)); 529 IdResolver.AddDecl(Param); 530 } 531 return DeclPtrTy::make(Param); 532} 533 534/// \brief Adds a default argument to the given non-type template 535/// parameter. 536void Sema::ActOnNonTypeTemplateParameterDefault(DeclPtrTy TemplateParamD, 537 SourceLocation EqualLoc, 538 ExprArg DefaultE) { 539 NonTypeTemplateParmDecl *TemplateParm 540 = cast<NonTypeTemplateParmDecl>(TemplateParamD.getAs<Decl>()); 541 Expr *Default = static_cast<Expr *>(DefaultE.get()); 542 543 // C++ [temp.param]p14: 544 // A template-parameter shall not be used in its own default argument. 545 // FIXME: Implement this check! Needs a recursive walk over the types. 546 547 // Check the well-formedness of the default template argument. 548 TemplateArgument Converted; 549 if (CheckTemplateArgument(TemplateParm, TemplateParm->getType(), Default, 550 Converted)) { 551 TemplateParm->setInvalidDecl(); 552 return; 553 } 554 555 TemplateParm->setDefaultArgument(DefaultE.takeAs<Expr>()); 556} 557 558 559/// ActOnTemplateTemplateParameter - Called when a C++ template template 560/// parameter (e.g. T in template <template <typename> class T> class array) 561/// has been parsed. S is the current scope. 562Sema::DeclPtrTy Sema::ActOnTemplateTemplateParameter(Scope* S, 563 SourceLocation TmpLoc, 564 TemplateParamsTy *Params, 565 IdentifierInfo *Name, 566 SourceLocation NameLoc, 567 unsigned Depth, 568 unsigned Position) { 569 assert(S->isTemplateParamScope() && 570 "Template template parameter not in template parameter scope!"); 571 572 // Construct the parameter object. 573 TemplateTemplateParmDecl *Param = 574 TemplateTemplateParmDecl::Create(Context, CurContext, TmpLoc, Depth, 575 Position, Name, 576 (TemplateParameterList*)Params); 577 578 // Make sure the parameter is valid. 579 // FIXME: Decl object is not currently invalidated anywhere so this doesn't 580 // do anything yet. However, if the template parameter list or (eventual) 581 // default value is ever invalidated, that will propagate here. 582 bool Invalid = false; 583 if (Invalid) { 584 Param->setInvalidDecl(); 585 } 586 587 // If the tt-param has a name, then link the identifier into the scope 588 // and lookup mechanisms. 589 if (Name) { 590 S->AddDecl(DeclPtrTy::make(Param)); 591 IdResolver.AddDecl(Param); 592 } 593 594 return DeclPtrTy::make(Param); 595} 596 597/// \brief Adds a default argument to the given template template 598/// parameter. 599void Sema::ActOnTemplateTemplateParameterDefault(DeclPtrTy TemplateParamD, 600 SourceLocation EqualLoc, 601 const ParsedTemplateArgument &Default) { 602 TemplateTemplateParmDecl *TemplateParm 603 = cast<TemplateTemplateParmDecl>(TemplateParamD.getAs<Decl>()); 604 605 // C++ [temp.param]p14: 606 // A template-parameter shall not be used in its own default argument. 607 // FIXME: Implement this check! Needs a recursive walk over the types. 608 609 // Check only that we have a template template argument. We don't want to 610 // try to check well-formedness now, because our template template parameter 611 // might have dependent types in its template parameters, which we wouldn't 612 // be able to match now. 613 // 614 // If none of the template template parameter's template arguments mention 615 // other template parameters, we could actually perform more checking here. 616 // However, it isn't worth doing. 617 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); 618 if (DefaultArg.getArgument().getAsTemplate().isNull()) { 619 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) 620 << DefaultArg.getSourceRange(); 621 return; 622 } 623 624 TemplateParm->setDefaultArgument(DefaultArg); 625} 626 627/// ActOnTemplateParameterList - Builds a TemplateParameterList that 628/// contains the template parameters in Params/NumParams. 629Sema::TemplateParamsTy * 630Sema::ActOnTemplateParameterList(unsigned Depth, 631 SourceLocation ExportLoc, 632 SourceLocation TemplateLoc, 633 SourceLocation LAngleLoc, 634 DeclPtrTy *Params, unsigned NumParams, 635 SourceLocation RAngleLoc) { 636 if (ExportLoc.isValid()) 637 Diag(ExportLoc, diag::warn_template_export_unsupported); 638 639 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, 640 (NamedDecl**)Params, NumParams, 641 RAngleLoc); 642} 643 644Sema::DeclResult 645Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, 646 SourceLocation KWLoc, const CXXScopeSpec &SS, 647 IdentifierInfo *Name, SourceLocation NameLoc, 648 AttributeList *Attr, 649 TemplateParameterList *TemplateParams, 650 AccessSpecifier AS) { 651 assert(TemplateParams && TemplateParams->size() > 0 && 652 "No template parameters"); 653 assert(TUK != TUK_Reference && "Can only declare or define class templates"); 654 bool Invalid = false; 655 656 // Check that we can declare a template here. 657 if (CheckTemplateDeclScope(S, TemplateParams)) 658 return true; 659 660 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 661 assert(Kind != TagDecl::TK_enum && "can't build template of enumerated type"); 662 663 // There is no such thing as an unnamed class template. 664 if (!Name) { 665 Diag(KWLoc, diag::err_template_unnamed_class); 666 return true; 667 } 668 669 // Find any previous declaration with this name. 670 DeclContext *SemanticContext; 671 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, 672 ForRedeclaration); 673 if (SS.isNotEmpty() && !SS.isInvalid()) { 674 if (RequireCompleteDeclContext(SS)) 675 return true; 676 677 SemanticContext = computeDeclContext(SS, true); 678 if (!SemanticContext) { 679 // FIXME: Produce a reasonable diagnostic here 680 return true; 681 } 682 683 LookupQualifiedName(Previous, SemanticContext); 684 } else { 685 SemanticContext = CurContext; 686 LookupName(Previous, S); 687 } 688 689 assert(!Previous.isAmbiguous() && "Ambiguity in class template redecl?"); 690 NamedDecl *PrevDecl = 0; 691 if (Previous.begin() != Previous.end()) 692 PrevDecl = *Previous.begin(); 693 694 // If there is a previous declaration with the same name, check 695 // whether this is a valid redeclaration. 696 ClassTemplateDecl *PrevClassTemplate 697 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); 698 699 // We may have found the injected-class-name of a class template, 700 // class template partial specialization, or class template specialization. 701 // In these cases, grab the template that is being defined or specialized. 702 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && 703 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { 704 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); 705 PrevClassTemplate 706 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); 707 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { 708 PrevClassTemplate 709 = cast<ClassTemplateSpecializationDecl>(PrevDecl) 710 ->getSpecializedTemplate(); 711 } 712 } 713 714 if (TUK == TUK_Friend) { 715 // C++ [namespace.memdef]p3: 716 // [...] When looking for a prior declaration of a class or a function 717 // declared as a friend, and when the name of the friend class or 718 // function is neither a qualified name nor a template-id, scopes outside 719 // the innermost enclosing namespace scope are not considered. 720 DeclContext *OutermostContext = CurContext; 721 while (!OutermostContext->isFileContext()) 722 OutermostContext = OutermostContext->getLookupParent(); 723 724 if (PrevDecl && 725 (OutermostContext->Equals(PrevDecl->getDeclContext()) || 726 OutermostContext->Encloses(PrevDecl->getDeclContext()))) { 727 SemanticContext = PrevDecl->getDeclContext(); 728 } else { 729 // Declarations in outer scopes don't matter. However, the outermost 730 // context we computed is the semantic context for our new 731 // declaration. 732 PrevDecl = PrevClassTemplate = 0; 733 SemanticContext = OutermostContext; 734 } 735 736 if (CurContext->isDependentContext()) { 737 // If this is a dependent context, we don't want to link the friend 738 // class template to the template in scope, because that would perform 739 // checking of the template parameter lists that can't be performed 740 // until the outer context is instantiated. 741 PrevDecl = PrevClassTemplate = 0; 742 } 743 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) 744 PrevDecl = PrevClassTemplate = 0; 745 746 if (PrevClassTemplate) { 747 // Ensure that the template parameter lists are compatible. 748 if (!TemplateParameterListsAreEqual(TemplateParams, 749 PrevClassTemplate->getTemplateParameters(), 750 /*Complain=*/true, 751 TPL_TemplateMatch)) 752 return true; 753 754 // C++ [temp.class]p4: 755 // In a redeclaration, partial specialization, explicit 756 // specialization or explicit instantiation of a class template, 757 // the class-key shall agree in kind with the original class 758 // template declaration (7.1.5.3). 759 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); 760 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) { 761 Diag(KWLoc, diag::err_use_with_wrong_tag) 762 << Name 763 << CodeModificationHint::CreateReplacement(KWLoc, 764 PrevRecordDecl->getKindName()); 765 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); 766 Kind = PrevRecordDecl->getTagKind(); 767 } 768 769 // Check for redefinition of this class template. 770 if (TUK == TUK_Definition) { 771 if (TagDecl *Def = PrevRecordDecl->getDefinition(Context)) { 772 Diag(NameLoc, diag::err_redefinition) << Name; 773 Diag(Def->getLocation(), diag::note_previous_definition); 774 // FIXME: Would it make sense to try to "forget" the previous 775 // definition, as part of error recovery? 776 return true; 777 } 778 } 779 } else if (PrevDecl && PrevDecl->isTemplateParameter()) { 780 // Maybe we will complain about the shadowed template parameter. 781 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 782 // Just pretend that we didn't see the previous declaration. 783 PrevDecl = 0; 784 } else if (PrevDecl) { 785 // C++ [temp]p5: 786 // A class template shall not have the same name as any other 787 // template, class, function, object, enumeration, enumerator, 788 // namespace, or type in the same scope (3.3), except as specified 789 // in (14.5.4). 790 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 791 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 792 return true; 793 } 794 795 // Check the template parameter list of this declaration, possibly 796 // merging in the template parameter list from the previous class 797 // template declaration. 798 if (CheckTemplateParameterList(TemplateParams, 799 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0, 800 TPC_ClassTemplate)) 801 Invalid = true; 802 803 // FIXME: If we had a scope specifier, we better have a previous template 804 // declaration! 805 806 CXXRecordDecl *NewClass = 807 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc, 808 PrevClassTemplate? 809 PrevClassTemplate->getTemplatedDecl() : 0, 810 /*DelayTypeCreation=*/true); 811 812 ClassTemplateDecl *NewTemplate 813 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, 814 DeclarationName(Name), TemplateParams, 815 NewClass, PrevClassTemplate); 816 NewClass->setDescribedClassTemplate(NewTemplate); 817 818 // Build the type for the class template declaration now. 819 QualType T = 820 Context.getTypeDeclType(NewClass, 821 PrevClassTemplate? 822 PrevClassTemplate->getTemplatedDecl() : 0); 823 assert(T->isDependentType() && "Class template type is not dependent?"); 824 (void)T; 825 826 // If we are providing an explicit specialization of a member that is a 827 // class template, make a note of that. 828 if (PrevClassTemplate && 829 PrevClassTemplate->getInstantiatedFromMemberTemplate()) 830 PrevClassTemplate->setMemberSpecialization(); 831 832 // Set the access specifier. 833 if (!Invalid && TUK != TUK_Friend) 834 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); 835 836 // Set the lexical context of these templates 837 NewClass->setLexicalDeclContext(CurContext); 838 NewTemplate->setLexicalDeclContext(CurContext); 839 840 if (TUK == TUK_Definition) 841 NewClass->startDefinition(); 842 843 if (Attr) 844 ProcessDeclAttributeList(S, NewClass, Attr); 845 846 if (TUK != TUK_Friend) 847 PushOnScopeChains(NewTemplate, S); 848 else { 849 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { 850 NewTemplate->setAccess(PrevClassTemplate->getAccess()); 851 NewClass->setAccess(PrevClassTemplate->getAccess()); 852 } 853 854 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ 855 PrevClassTemplate != NULL); 856 857 // Friend templates are visible in fairly strange ways. 858 if (!CurContext->isDependentContext()) { 859 DeclContext *DC = SemanticContext->getLookupContext(); 860 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false); 861 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 862 PushOnScopeChains(NewTemplate, EnclosingScope, 863 /* AddToContext = */ false); 864 } 865 866 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 867 NewClass->getLocation(), 868 NewTemplate, 869 /*FIXME:*/NewClass->getLocation()); 870 Friend->setAccess(AS_public); 871 CurContext->addDecl(Friend); 872 } 873 874 if (Invalid) { 875 NewTemplate->setInvalidDecl(); 876 NewClass->setInvalidDecl(); 877 } 878 return DeclPtrTy::make(NewTemplate); 879} 880 881/// \brief Diagnose the presence of a default template argument on a 882/// template parameter, which is ill-formed in certain contexts. 883/// 884/// \returns true if the default template argument should be dropped. 885static bool DiagnoseDefaultTemplateArgument(Sema &S, 886 Sema::TemplateParamListContext TPC, 887 SourceLocation ParamLoc, 888 SourceRange DefArgRange) { 889 switch (TPC) { 890 case Sema::TPC_ClassTemplate: 891 return false; 892 893 case Sema::TPC_FunctionTemplate: 894 // C++ [temp.param]p9: 895 // A default template-argument shall not be specified in a 896 // function template declaration or a function template 897 // definition [...] 898 // (This sentence is not in C++0x, per DR226). 899 if (!S.getLangOptions().CPlusPlus0x) 900 S.Diag(ParamLoc, 901 diag::err_template_parameter_default_in_function_template) 902 << DefArgRange; 903 return false; 904 905 case Sema::TPC_ClassTemplateMember: 906 // C++0x [temp.param]p9: 907 // A default template-argument shall not be specified in the 908 // template-parameter-lists of the definition of a member of a 909 // class template that appears outside of the member's class. 910 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member) 911 << DefArgRange; 912 return true; 913 914 case Sema::TPC_FriendFunctionTemplate: 915 // C++ [temp.param]p9: 916 // A default template-argument shall not be specified in a 917 // friend template declaration. 918 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template) 919 << DefArgRange; 920 return true; 921 922 // FIXME: C++0x [temp.param]p9 allows default template-arguments 923 // for friend function templates if there is only a single 924 // declaration (and it is a definition). Strange! 925 } 926 927 return false; 928} 929 930/// \brief Checks the validity of a template parameter list, possibly 931/// considering the template parameter list from a previous 932/// declaration. 933/// 934/// If an "old" template parameter list is provided, it must be 935/// equivalent (per TemplateParameterListsAreEqual) to the "new" 936/// template parameter list. 937/// 938/// \param NewParams Template parameter list for a new template 939/// declaration. This template parameter list will be updated with any 940/// default arguments that are carried through from the previous 941/// template parameter list. 942/// 943/// \param OldParams If provided, template parameter list from a 944/// previous declaration of the same template. Default template 945/// arguments will be merged from the old template parameter list to 946/// the new template parameter list. 947/// 948/// \param TPC Describes the context in which we are checking the given 949/// template parameter list. 950/// 951/// \returns true if an error occurred, false otherwise. 952bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, 953 TemplateParameterList *OldParams, 954 TemplateParamListContext TPC) { 955 bool Invalid = false; 956 957 // C++ [temp.param]p10: 958 // The set of default template-arguments available for use with a 959 // template declaration or definition is obtained by merging the 960 // default arguments from the definition (if in scope) and all 961 // declarations in scope in the same way default function 962 // arguments are (8.3.6). 963 bool SawDefaultArgument = false; 964 SourceLocation PreviousDefaultArgLoc; 965 966 bool SawParameterPack = false; 967 SourceLocation ParameterPackLoc; 968 969 // Dummy initialization to avoid warnings. 970 TemplateParameterList::iterator OldParam = NewParams->end(); 971 if (OldParams) 972 OldParam = OldParams->begin(); 973 974 for (TemplateParameterList::iterator NewParam = NewParams->begin(), 975 NewParamEnd = NewParams->end(); 976 NewParam != NewParamEnd; ++NewParam) { 977 // Variables used to diagnose redundant default arguments 978 bool RedundantDefaultArg = false; 979 SourceLocation OldDefaultLoc; 980 SourceLocation NewDefaultLoc; 981 982 // Variables used to diagnose missing default arguments 983 bool MissingDefaultArg = false; 984 985 // C++0x [temp.param]p11: 986 // If a template parameter of a class template is a template parameter pack, 987 // it must be the last template parameter. 988 if (SawParameterPack) { 989 Diag(ParameterPackLoc, 990 diag::err_template_param_pack_must_be_last_template_parameter); 991 Invalid = true; 992 } 993 994 if (TemplateTypeParmDecl *NewTypeParm 995 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { 996 // Check the presence of a default argument here. 997 if (NewTypeParm->hasDefaultArgument() && 998 DiagnoseDefaultTemplateArgument(*this, TPC, 999 NewTypeParm->getLocation(), 1000 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc() 1001 .getFullSourceRange())) 1002 NewTypeParm->removeDefaultArgument(); 1003 1004 // Merge default arguments for template type parameters. 1005 TemplateTypeParmDecl *OldTypeParm 1006 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; 1007 1008 if (NewTypeParm->isParameterPack()) { 1009 assert(!NewTypeParm->hasDefaultArgument() && 1010 "Parameter packs can't have a default argument!"); 1011 SawParameterPack = true; 1012 ParameterPackLoc = NewTypeParm->getLocation(); 1013 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && 1014 NewTypeParm->hasDefaultArgument()) { 1015 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); 1016 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); 1017 SawDefaultArgument = true; 1018 RedundantDefaultArg = true; 1019 PreviousDefaultArgLoc = NewDefaultLoc; 1020 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { 1021 // Merge the default argument from the old declaration to the 1022 // new declaration. 1023 SawDefaultArgument = true; 1024 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), 1025 true); 1026 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); 1027 } else if (NewTypeParm->hasDefaultArgument()) { 1028 SawDefaultArgument = true; 1029 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); 1030 } else if (SawDefaultArgument) 1031 MissingDefaultArg = true; 1032 } else if (NonTypeTemplateParmDecl *NewNonTypeParm 1033 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { 1034 // Check the presence of a default argument here. 1035 if (NewNonTypeParm->hasDefaultArgument() && 1036 DiagnoseDefaultTemplateArgument(*this, TPC, 1037 NewNonTypeParm->getLocation(), 1038 NewNonTypeParm->getDefaultArgument()->getSourceRange())) { 1039 NewNonTypeParm->getDefaultArgument()->Destroy(Context); 1040 NewNonTypeParm->setDefaultArgument(0); 1041 } 1042 1043 // Merge default arguments for non-type template parameters 1044 NonTypeTemplateParmDecl *OldNonTypeParm 1045 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; 1046 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && 1047 NewNonTypeParm->hasDefaultArgument()) { 1048 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1049 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1050 SawDefaultArgument = true; 1051 RedundantDefaultArg = true; 1052 PreviousDefaultArgLoc = NewDefaultLoc; 1053 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { 1054 // Merge the default argument from the old declaration to the 1055 // new declaration. 1056 SawDefaultArgument = true; 1057 // FIXME: We need to create a new kind of "default argument" 1058 // expression that points to a previous template template 1059 // parameter. 1060 NewNonTypeParm->setDefaultArgument( 1061 OldNonTypeParm->getDefaultArgument()); 1062 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1063 } else if (NewNonTypeParm->hasDefaultArgument()) { 1064 SawDefaultArgument = true; 1065 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1066 } else if (SawDefaultArgument) 1067 MissingDefaultArg = true; 1068 } else { 1069 // Check the presence of a default argument here. 1070 TemplateTemplateParmDecl *NewTemplateParm 1071 = cast<TemplateTemplateParmDecl>(*NewParam); 1072 if (NewTemplateParm->hasDefaultArgument() && 1073 DiagnoseDefaultTemplateArgument(*this, TPC, 1074 NewTemplateParm->getLocation(), 1075 NewTemplateParm->getDefaultArgument().getSourceRange())) 1076 NewTemplateParm->setDefaultArgument(TemplateArgumentLoc()); 1077 1078 // Merge default arguments for template template parameters 1079 TemplateTemplateParmDecl *OldTemplateParm 1080 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; 1081 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && 1082 NewTemplateParm->hasDefaultArgument()) { 1083 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); 1084 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); 1085 SawDefaultArgument = true; 1086 RedundantDefaultArg = true; 1087 PreviousDefaultArgLoc = NewDefaultLoc; 1088 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { 1089 // Merge the default argument from the old declaration to the 1090 // new declaration. 1091 SawDefaultArgument = true; 1092 // FIXME: We need to create a new kind of "default argument" expression 1093 // that points to a previous template template parameter. 1094 NewTemplateParm->setDefaultArgument( 1095 OldTemplateParm->getDefaultArgument()); 1096 PreviousDefaultArgLoc 1097 = OldTemplateParm->getDefaultArgument().getLocation(); 1098 } else if (NewTemplateParm->hasDefaultArgument()) { 1099 SawDefaultArgument = true; 1100 PreviousDefaultArgLoc 1101 = NewTemplateParm->getDefaultArgument().getLocation(); 1102 } else if (SawDefaultArgument) 1103 MissingDefaultArg = true; 1104 } 1105 1106 if (RedundantDefaultArg) { 1107 // C++ [temp.param]p12: 1108 // A template-parameter shall not be given default arguments 1109 // by two different declarations in the same scope. 1110 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); 1111 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); 1112 Invalid = true; 1113 } else if (MissingDefaultArg) { 1114 // C++ [temp.param]p11: 1115 // If a template-parameter has a default template-argument, 1116 // all subsequent template-parameters shall have a default 1117 // template-argument supplied. 1118 Diag((*NewParam)->getLocation(), 1119 diag::err_template_param_default_arg_missing); 1120 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); 1121 Invalid = true; 1122 } 1123 1124 // If we have an old template parameter list that we're merging 1125 // in, move on to the next parameter. 1126 if (OldParams) 1127 ++OldParam; 1128 } 1129 1130 return Invalid; 1131} 1132 1133/// \brief Match the given template parameter lists to the given scope 1134/// specifier, returning the template parameter list that applies to the 1135/// name. 1136/// 1137/// \param DeclStartLoc the start of the declaration that has a scope 1138/// specifier or a template parameter list. 1139/// 1140/// \param SS the scope specifier that will be matched to the given template 1141/// parameter lists. This scope specifier precedes a qualified name that is 1142/// being declared. 1143/// 1144/// \param ParamLists the template parameter lists, from the outermost to the 1145/// innermost template parameter lists. 1146/// 1147/// \param NumParamLists the number of template parameter lists in ParamLists. 1148/// 1149/// \param IsExplicitSpecialization will be set true if the entity being 1150/// declared is an explicit specialization, false otherwise. 1151/// 1152/// \returns the template parameter list, if any, that corresponds to the 1153/// name that is preceded by the scope specifier @p SS. This template 1154/// parameter list may be have template parameters (if we're declaring a 1155/// template) or may have no template parameters (if we're declaring a 1156/// template specialization), or may be NULL (if we were's declaring isn't 1157/// itself a template). 1158TemplateParameterList * 1159Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, 1160 const CXXScopeSpec &SS, 1161 TemplateParameterList **ParamLists, 1162 unsigned NumParamLists, 1163 bool &IsExplicitSpecialization) { 1164 IsExplicitSpecialization = false; 1165 1166 // Find the template-ids that occur within the nested-name-specifier. These 1167 // template-ids will match up with the template parameter lists. 1168 llvm::SmallVector<const TemplateSpecializationType *, 4> 1169 TemplateIdsInSpecifier; 1170 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4> 1171 ExplicitSpecializationsInSpecifier; 1172 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 1173 NNS; NNS = NNS->getPrefix()) { 1174 const Type *T = NNS->getAsType(); 1175 if (!T) break; 1176 1177 // C++0x [temp.expl.spec]p17: 1178 // A member or a member template may be nested within many 1179 // enclosing class templates. In an explicit specialization for 1180 // such a member, the member declaration shall be preceded by a 1181 // template<> for each enclosing class template that is 1182 // explicitly specialized. 1183 // We interpret this as forbidding typedefs of template 1184 // specializations in the scope specifiers of out-of-line decls. 1185 if (const TypedefType *TT = dyn_cast<TypedefType>(T)) { 1186 const Type *UnderlyingT = TT->LookThroughTypedefs().getTypePtr(); 1187 if (isa<TemplateSpecializationType>(UnderlyingT)) 1188 // FIXME: better source location information. 1189 Diag(DeclStartLoc, diag::err_typedef_in_def_scope) << QualType(T,0); 1190 T = UnderlyingT; 1191 } 1192 1193 if (const TemplateSpecializationType *SpecType 1194 = dyn_cast<TemplateSpecializationType>(T)) { 1195 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl(); 1196 if (!Template) 1197 continue; // FIXME: should this be an error? probably... 1198 1199 if (const RecordType *Record = SpecType->getAs<RecordType>()) { 1200 ClassTemplateSpecializationDecl *SpecDecl 1201 = cast<ClassTemplateSpecializationDecl>(Record->getDecl()); 1202 // If the nested name specifier refers to an explicit specialization, 1203 // we don't need a template<> header. 1204 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) { 1205 ExplicitSpecializationsInSpecifier.push_back(SpecDecl); 1206 continue; 1207 } 1208 } 1209 1210 TemplateIdsInSpecifier.push_back(SpecType); 1211 } 1212 } 1213 1214 // Reverse the list of template-ids in the scope specifier, so that we can 1215 // more easily match up the template-ids and the template parameter lists. 1216 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end()); 1217 1218 SourceLocation FirstTemplateLoc = DeclStartLoc; 1219 if (NumParamLists) 1220 FirstTemplateLoc = ParamLists[0]->getTemplateLoc(); 1221 1222 // Match the template-ids found in the specifier to the template parameter 1223 // lists. 1224 unsigned Idx = 0; 1225 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size(); 1226 Idx != NumTemplateIds; ++Idx) { 1227 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0); 1228 bool DependentTemplateId = TemplateId->isDependentType(); 1229 if (Idx >= NumParamLists) { 1230 // We have a template-id without a corresponding template parameter 1231 // list. 1232 if (DependentTemplateId) { 1233 // FIXME: the location information here isn't great. 1234 Diag(SS.getRange().getBegin(), 1235 diag::err_template_spec_needs_template_parameters) 1236 << TemplateId 1237 << SS.getRange(); 1238 } else { 1239 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header) 1240 << SS.getRange() 1241 << CodeModificationHint::CreateInsertion(FirstTemplateLoc, 1242 "template<> "); 1243 IsExplicitSpecialization = true; 1244 } 1245 return 0; 1246 } 1247 1248 // Check the template parameter list against its corresponding template-id. 1249 if (DependentTemplateId) { 1250 TemplateDecl *Template 1251 = TemplateIdsInSpecifier[Idx]->getTemplateName().getAsTemplateDecl(); 1252 1253 if (ClassTemplateDecl *ClassTemplate 1254 = dyn_cast<ClassTemplateDecl>(Template)) { 1255 TemplateParameterList *ExpectedTemplateParams = 0; 1256 // Is this template-id naming the primary template? 1257 if (Context.hasSameType(TemplateId, 1258 ClassTemplate->getInjectedClassNameType(Context))) 1259 ExpectedTemplateParams = ClassTemplate->getTemplateParameters(); 1260 // ... or a partial specialization? 1261 else if (ClassTemplatePartialSpecializationDecl *PartialSpec 1262 = ClassTemplate->findPartialSpecialization(TemplateId)) 1263 ExpectedTemplateParams = PartialSpec->getTemplateParameters(); 1264 1265 if (ExpectedTemplateParams) 1266 TemplateParameterListsAreEqual(ParamLists[Idx], 1267 ExpectedTemplateParams, 1268 true, TPL_TemplateMatch); 1269 } 1270 1271 CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember); 1272 } else if (ParamLists[Idx]->size() > 0) 1273 Diag(ParamLists[Idx]->getTemplateLoc(), 1274 diag::err_template_param_list_matches_nontemplate) 1275 << TemplateId 1276 << ParamLists[Idx]->getSourceRange(); 1277 else 1278 IsExplicitSpecialization = true; 1279 } 1280 1281 // If there were at least as many template-ids as there were template 1282 // parameter lists, then there are no template parameter lists remaining for 1283 // the declaration itself. 1284 if (Idx >= NumParamLists) 1285 return 0; 1286 1287 // If there were too many template parameter lists, complain about that now. 1288 if (Idx != NumParamLists - 1) { 1289 while (Idx < NumParamLists - 1) { 1290 bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0; 1291 Diag(ParamLists[Idx]->getTemplateLoc(), 1292 isExplicitSpecHeader? diag::warn_template_spec_extra_headers 1293 : diag::err_template_spec_extra_headers) 1294 << SourceRange(ParamLists[Idx]->getTemplateLoc(), 1295 ParamLists[Idx]->getRAngleLoc()); 1296 1297 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) { 1298 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(), 1299 diag::note_explicit_template_spec_does_not_need_header) 1300 << ExplicitSpecializationsInSpecifier.back(); 1301 ExplicitSpecializationsInSpecifier.pop_back(); 1302 } 1303 1304 ++Idx; 1305 } 1306 } 1307 1308 // Return the last template parameter list, which corresponds to the 1309 // entity being declared. 1310 return ParamLists[NumParamLists - 1]; 1311} 1312 1313QualType Sema::CheckTemplateIdType(TemplateName Name, 1314 SourceLocation TemplateLoc, 1315 const TemplateArgumentListInfo &TemplateArgs) { 1316 TemplateDecl *Template = Name.getAsTemplateDecl(); 1317 if (!Template) { 1318 // The template name does not resolve to a template, so we just 1319 // build a dependent template-id type. 1320 return Context.getTemplateSpecializationType(Name, TemplateArgs); 1321 } 1322 1323 // Check that the template argument list is well-formed for this 1324 // template. 1325 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(), 1326 TemplateArgs.size()); 1327 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs, 1328 false, Converted)) 1329 return QualType(); 1330 1331 assert((Converted.structuredSize() == 1332 Template->getTemplateParameters()->size()) && 1333 "Converted template argument list is too short!"); 1334 1335 QualType CanonType; 1336 1337 if (Name.isDependent() || 1338 TemplateSpecializationType::anyDependentTemplateArguments( 1339 TemplateArgs)) { 1340 // This class template specialization is a dependent 1341 // type. Therefore, its canonical type is another class template 1342 // specialization type that contains all of the converted 1343 // arguments in canonical form. This ensures that, e.g., A<T> and 1344 // A<T, T> have identical types when A is declared as: 1345 // 1346 // template<typename T, typename U = T> struct A; 1347 TemplateName CanonName = Context.getCanonicalTemplateName(Name); 1348 CanonType = Context.getTemplateSpecializationType(CanonName, 1349 Converted.getFlatArguments(), 1350 Converted.flatSize()); 1351 1352 // FIXME: CanonType is not actually the canonical type, and unfortunately 1353 // it is a TemplateSpecializationType that we will never use again. 1354 // In the future, we need to teach getTemplateSpecializationType to only 1355 // build the canonical type and return that to us. 1356 CanonType = Context.getCanonicalType(CanonType); 1357 } else if (ClassTemplateDecl *ClassTemplate 1358 = dyn_cast<ClassTemplateDecl>(Template)) { 1359 // Find the class template specialization declaration that 1360 // corresponds to these arguments. 1361 llvm::FoldingSetNodeID ID; 1362 ClassTemplateSpecializationDecl::Profile(ID, 1363 Converted.getFlatArguments(), 1364 Converted.flatSize(), 1365 Context); 1366 void *InsertPos = 0; 1367 ClassTemplateSpecializationDecl *Decl 1368 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 1369 if (!Decl) { 1370 // This is the first time we have referenced this class template 1371 // specialization. Create the canonical declaration and add it to 1372 // the set of specializations. 1373 Decl = ClassTemplateSpecializationDecl::Create(Context, 1374 ClassTemplate->getDeclContext(), 1375 ClassTemplate->getLocation(), 1376 ClassTemplate, 1377 Converted, 0); 1378 ClassTemplate->getSpecializations().InsertNode(Decl, InsertPos); 1379 Decl->setLexicalDeclContext(CurContext); 1380 } 1381 1382 CanonType = Context.getTypeDeclType(Decl); 1383 } 1384 1385 // Build the fully-sugared type for this class template 1386 // specialization, which refers back to the class template 1387 // specialization we created or found. 1388 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); 1389} 1390 1391Action::TypeResult 1392Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc, 1393 SourceLocation LAngleLoc, 1394 ASTTemplateArgsPtr TemplateArgsIn, 1395 SourceLocation RAngleLoc) { 1396 TemplateName Template = TemplateD.getAsVal<TemplateName>(); 1397 1398 // Translate the parser's template argument list in our AST format. 1399 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 1400 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 1401 1402 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); 1403 TemplateArgsIn.release(); 1404 1405 if (Result.isNull()) 1406 return true; 1407 1408 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result); 1409 TemplateSpecializationTypeLoc TL 1410 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc()); 1411 TL.setTemplateNameLoc(TemplateLoc); 1412 TL.setLAngleLoc(LAngleLoc); 1413 TL.setRAngleLoc(RAngleLoc); 1414 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) 1415 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); 1416 1417 return CreateLocInfoType(Result, DI).getAsOpaquePtr(); 1418} 1419 1420Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult, 1421 TagUseKind TUK, 1422 DeclSpec::TST TagSpec, 1423 SourceLocation TagLoc) { 1424 if (TypeResult.isInvalid()) 1425 return Sema::TypeResult(); 1426 1427 // FIXME: preserve source info, ideally without copying the DI. 1428 TypeSourceInfo *DI; 1429 QualType Type = GetTypeFromParser(TypeResult.get(), &DI); 1430 1431 // Verify the tag specifier. 1432 TagDecl::TagKind TagKind = TagDecl::getTagKindForTypeSpec(TagSpec); 1433 1434 if (const RecordType *RT = Type->getAs<RecordType>()) { 1435 RecordDecl *D = RT->getDecl(); 1436 1437 IdentifierInfo *Id = D->getIdentifier(); 1438 assert(Id && "templated class must have an identifier"); 1439 1440 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) { 1441 Diag(TagLoc, diag::err_use_with_wrong_tag) 1442 << Type 1443 << CodeModificationHint::CreateReplacement(SourceRange(TagLoc), 1444 D->getKindName()); 1445 Diag(D->getLocation(), diag::note_previous_use); 1446 } 1447 } 1448 1449 QualType ElabType = Context.getElaboratedType(Type, TagKind); 1450 1451 return ElabType.getAsOpaquePtr(); 1452} 1453 1454Sema::OwningExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS, 1455 LookupResult &R, 1456 bool RequiresADL, 1457 const TemplateArgumentListInfo &TemplateArgs) { 1458 // FIXME: Can we do any checking at this point? I guess we could check the 1459 // template arguments that we have against the template name, if the template 1460 // name refers to a single template. That's not a terribly common case, 1461 // though. 1462 1463 // These should be filtered out by our callers. 1464 assert(!R.empty() && "empty lookup results when building templateid"); 1465 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid"); 1466 1467 NestedNameSpecifier *Qualifier = 0; 1468 SourceRange QualifierRange; 1469 if (SS.isSet()) { 1470 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 1471 QualifierRange = SS.getRange(); 1472 } 1473 1474 bool Dependent 1475 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 1476 &TemplateArgs); 1477 UnresolvedLookupExpr *ULE 1478 = UnresolvedLookupExpr::Create(Context, Dependent, 1479 Qualifier, QualifierRange, 1480 R.getLookupName(), R.getNameLoc(), 1481 RequiresADL, TemplateArgs); 1482 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 1483 ULE->addDecl(*I); 1484 1485 return Owned(ULE); 1486} 1487 1488// We actually only call this from template instantiation. 1489Sema::OwningExprResult 1490Sema::BuildQualifiedTemplateIdExpr(const CXXScopeSpec &SS, 1491 DeclarationName Name, 1492 SourceLocation NameLoc, 1493 const TemplateArgumentListInfo &TemplateArgs) { 1494 DeclContext *DC; 1495 if (!(DC = computeDeclContext(SS, false)) || 1496 DC->isDependentContext() || 1497 RequireCompleteDeclContext(SS)) 1498 return BuildDependentDeclRefExpr(SS, Name, NameLoc, &TemplateArgs); 1499 1500 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1501 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false); 1502 1503 if (R.isAmbiguous()) 1504 return ExprError(); 1505 1506 if (R.empty()) { 1507 Diag(NameLoc, diag::err_template_kw_refers_to_non_template) 1508 << Name << SS.getRange(); 1509 return ExprError(); 1510 } 1511 1512 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) { 1513 Diag(NameLoc, diag::err_template_kw_refers_to_class_template) 1514 << (NestedNameSpecifier*) SS.getScopeRep() << Name << SS.getRange(); 1515 Diag(Temp->getLocation(), diag::note_referenced_class_template); 1516 return ExprError(); 1517 } 1518 1519 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs); 1520} 1521 1522/// \brief Form a dependent template name. 1523/// 1524/// This action forms a dependent template name given the template 1525/// name and its (presumably dependent) scope specifier. For 1526/// example, given "MetaFun::template apply", the scope specifier \p 1527/// SS will be "MetaFun::", \p TemplateKWLoc contains the location 1528/// of the "template" keyword, and "apply" is the \p Name. 1529Sema::TemplateTy 1530Sema::ActOnDependentTemplateName(SourceLocation TemplateKWLoc, 1531 const CXXScopeSpec &SS, 1532 UnqualifiedId &Name, 1533 TypeTy *ObjectType, 1534 bool EnteringContext) { 1535 if ((ObjectType && 1536 computeDeclContext(QualType::getFromOpaquePtr(ObjectType))) || 1537 (SS.isSet() && computeDeclContext(SS, EnteringContext))) { 1538 // C++0x [temp.names]p5: 1539 // If a name prefixed by the keyword template is not the name of 1540 // a template, the program is ill-formed. [Note: the keyword 1541 // template may not be applied to non-template members of class 1542 // templates. -end note ] [ Note: as is the case with the 1543 // typename prefix, the template prefix is allowed in cases 1544 // where it is not strictly necessary; i.e., when the 1545 // nested-name-specifier or the expression on the left of the -> 1546 // or . is not dependent on a template-parameter, or the use 1547 // does not appear in the scope of a template. -end note] 1548 // 1549 // Note: C++03 was more strict here, because it banned the use of 1550 // the "template" keyword prior to a template-name that was not a 1551 // dependent name. C++ DR468 relaxed this requirement (the 1552 // "template" keyword is now permitted). We follow the C++0x 1553 // rules, even in C++03 mode, retroactively applying the DR. 1554 TemplateTy Template; 1555 TemplateNameKind TNK = isTemplateName(0, SS, Name, ObjectType, 1556 EnteringContext, Template); 1557 if (TNK == TNK_Non_template) { 1558 Diag(Name.getSourceRange().getBegin(), 1559 diag::err_template_kw_refers_to_non_template) 1560 << GetNameFromUnqualifiedId(Name) 1561 << Name.getSourceRange(); 1562 return TemplateTy(); 1563 } 1564 1565 return Template; 1566 } 1567 1568 NestedNameSpecifier *Qualifier 1569 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1570 1571 switch (Name.getKind()) { 1572 case UnqualifiedId::IK_Identifier: 1573 return TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1574 Name.Identifier)); 1575 1576 case UnqualifiedId::IK_OperatorFunctionId: 1577 return TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1578 Name.OperatorFunctionId.Operator)); 1579 1580 case UnqualifiedId::IK_LiteralOperatorId: 1581 assert(false && "We don't support these; Parse shouldn't have allowed propagation"); 1582 1583 default: 1584 break; 1585 } 1586 1587 Diag(Name.getSourceRange().getBegin(), 1588 diag::err_template_kw_refers_to_non_template) 1589 << GetNameFromUnqualifiedId(Name) 1590 << Name.getSourceRange(); 1591 return TemplateTy(); 1592} 1593 1594bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, 1595 const TemplateArgumentLoc &AL, 1596 TemplateArgumentListBuilder &Converted) { 1597 const TemplateArgument &Arg = AL.getArgument(); 1598 1599 // Check template type parameter. 1600 if (Arg.getKind() != TemplateArgument::Type) { 1601 // C++ [temp.arg.type]p1: 1602 // A template-argument for a template-parameter which is a 1603 // type shall be a type-id. 1604 1605 // We have a template type parameter but the template argument 1606 // is not a type. 1607 SourceRange SR = AL.getSourceRange(); 1608 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; 1609 Diag(Param->getLocation(), diag::note_template_param_here); 1610 1611 return true; 1612 } 1613 1614 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo())) 1615 return true; 1616 1617 // Add the converted template type argument. 1618 Converted.Append( 1619 TemplateArgument(Context.getCanonicalType(Arg.getAsType()))); 1620 return false; 1621} 1622 1623/// \brief Substitute template arguments into the default template argument for 1624/// the given template type parameter. 1625/// 1626/// \param SemaRef the semantic analysis object for which we are performing 1627/// the substitution. 1628/// 1629/// \param Template the template that we are synthesizing template arguments 1630/// for. 1631/// 1632/// \param TemplateLoc the location of the template name that started the 1633/// template-id we are checking. 1634/// 1635/// \param RAngleLoc the location of the right angle bracket ('>') that 1636/// terminates the template-id. 1637/// 1638/// \param Param the template template parameter whose default we are 1639/// substituting into. 1640/// 1641/// \param Converted the list of template arguments provided for template 1642/// parameters that precede \p Param in the template parameter list. 1643/// 1644/// \returns the substituted template argument, or NULL if an error occurred. 1645static TypeSourceInfo * 1646SubstDefaultTemplateArgument(Sema &SemaRef, 1647 TemplateDecl *Template, 1648 SourceLocation TemplateLoc, 1649 SourceLocation RAngleLoc, 1650 TemplateTypeParmDecl *Param, 1651 TemplateArgumentListBuilder &Converted) { 1652 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo(); 1653 1654 // If the argument type is dependent, instantiate it now based 1655 // on the previously-computed template arguments. 1656 if (ArgType->getType()->isDependentType()) { 1657 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1658 /*TakeArgs=*/false); 1659 1660 MultiLevelTemplateArgumentList AllTemplateArgs 1661 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1662 1663 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1664 Template, Converted.getFlatArguments(), 1665 Converted.flatSize(), 1666 SourceRange(TemplateLoc, RAngleLoc)); 1667 1668 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, 1669 Param->getDefaultArgumentLoc(), 1670 Param->getDeclName()); 1671 } 1672 1673 return ArgType; 1674} 1675 1676/// \brief Substitute template arguments into the default template argument for 1677/// the given non-type template parameter. 1678/// 1679/// \param SemaRef the semantic analysis object for which we are performing 1680/// the substitution. 1681/// 1682/// \param Template the template that we are synthesizing template arguments 1683/// for. 1684/// 1685/// \param TemplateLoc the location of the template name that started the 1686/// template-id we are checking. 1687/// 1688/// \param RAngleLoc the location of the right angle bracket ('>') that 1689/// terminates the template-id. 1690/// 1691/// \param Param the non-type template parameter whose default we are 1692/// substituting into. 1693/// 1694/// \param Converted the list of template arguments provided for template 1695/// parameters that precede \p Param in the template parameter list. 1696/// 1697/// \returns the substituted template argument, or NULL if an error occurred. 1698static Sema::OwningExprResult 1699SubstDefaultTemplateArgument(Sema &SemaRef, 1700 TemplateDecl *Template, 1701 SourceLocation TemplateLoc, 1702 SourceLocation RAngleLoc, 1703 NonTypeTemplateParmDecl *Param, 1704 TemplateArgumentListBuilder &Converted) { 1705 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1706 /*TakeArgs=*/false); 1707 1708 MultiLevelTemplateArgumentList AllTemplateArgs 1709 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1710 1711 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1712 Template, Converted.getFlatArguments(), 1713 Converted.flatSize(), 1714 SourceRange(TemplateLoc, RAngleLoc)); 1715 1716 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); 1717} 1718 1719/// \brief Substitute template arguments into the default template argument for 1720/// the given template template parameter. 1721/// 1722/// \param SemaRef the semantic analysis object for which we are performing 1723/// the substitution. 1724/// 1725/// \param Template the template that we are synthesizing template arguments 1726/// for. 1727/// 1728/// \param TemplateLoc the location of the template name that started the 1729/// template-id we are checking. 1730/// 1731/// \param RAngleLoc the location of the right angle bracket ('>') that 1732/// terminates the template-id. 1733/// 1734/// \param Param the template template parameter whose default we are 1735/// substituting into. 1736/// 1737/// \param Converted the list of template arguments provided for template 1738/// parameters that precede \p Param in the template parameter list. 1739/// 1740/// \returns the substituted template argument, or NULL if an error occurred. 1741static TemplateName 1742SubstDefaultTemplateArgument(Sema &SemaRef, 1743 TemplateDecl *Template, 1744 SourceLocation TemplateLoc, 1745 SourceLocation RAngleLoc, 1746 TemplateTemplateParmDecl *Param, 1747 TemplateArgumentListBuilder &Converted) { 1748 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1749 /*TakeArgs=*/false); 1750 1751 MultiLevelTemplateArgumentList AllTemplateArgs 1752 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1753 1754 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1755 Template, Converted.getFlatArguments(), 1756 Converted.flatSize(), 1757 SourceRange(TemplateLoc, RAngleLoc)); 1758 1759 return SemaRef.SubstTemplateName( 1760 Param->getDefaultArgument().getArgument().getAsTemplate(), 1761 Param->getDefaultArgument().getTemplateNameLoc(), 1762 AllTemplateArgs); 1763} 1764 1765/// \brief If the given template parameter has a default template 1766/// argument, substitute into that default template argument and 1767/// return the corresponding template argument. 1768TemplateArgumentLoc 1769Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template, 1770 SourceLocation TemplateLoc, 1771 SourceLocation RAngleLoc, 1772 Decl *Param, 1773 TemplateArgumentListBuilder &Converted) { 1774 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) { 1775 if (!TypeParm->hasDefaultArgument()) 1776 return TemplateArgumentLoc(); 1777 1778 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template, 1779 TemplateLoc, 1780 RAngleLoc, 1781 TypeParm, 1782 Converted); 1783 if (DI) 1784 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI); 1785 1786 return TemplateArgumentLoc(); 1787 } 1788 1789 if (NonTypeTemplateParmDecl *NonTypeParm 1790 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1791 if (!NonTypeParm->hasDefaultArgument()) 1792 return TemplateArgumentLoc(); 1793 1794 OwningExprResult Arg = SubstDefaultTemplateArgument(*this, Template, 1795 TemplateLoc, 1796 RAngleLoc, 1797 NonTypeParm, 1798 Converted); 1799 if (Arg.isInvalid()) 1800 return TemplateArgumentLoc(); 1801 1802 Expr *ArgE = Arg.takeAs<Expr>(); 1803 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE); 1804 } 1805 1806 TemplateTemplateParmDecl *TempTempParm 1807 = cast<TemplateTemplateParmDecl>(Param); 1808 if (!TempTempParm->hasDefaultArgument()) 1809 return TemplateArgumentLoc(); 1810 1811 TemplateName TName = SubstDefaultTemplateArgument(*this, Template, 1812 TemplateLoc, 1813 RAngleLoc, 1814 TempTempParm, 1815 Converted); 1816 if (TName.isNull()) 1817 return TemplateArgumentLoc(); 1818 1819 return TemplateArgumentLoc(TemplateArgument(TName), 1820 TempTempParm->getDefaultArgument().getTemplateQualifierRange(), 1821 TempTempParm->getDefaultArgument().getTemplateNameLoc()); 1822} 1823 1824/// \brief Check that the given template argument corresponds to the given 1825/// template parameter. 1826bool Sema::CheckTemplateArgument(NamedDecl *Param, 1827 const TemplateArgumentLoc &Arg, 1828 TemplateDecl *Template, 1829 SourceLocation TemplateLoc, 1830 SourceLocation RAngleLoc, 1831 TemplateArgumentListBuilder &Converted) { 1832 // Check template type parameters. 1833 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) 1834 return CheckTemplateTypeArgument(TTP, Arg, Converted); 1835 1836 // Check non-type template parameters. 1837 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1838 // Do substitution on the type of the non-type template parameter 1839 // with the template arguments we've seen thus far. 1840 QualType NTTPType = NTTP->getType(); 1841 if (NTTPType->isDependentType()) { 1842 // Do substitution on the type of the non-type template parameter. 1843 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 1844 NTTP, Converted.getFlatArguments(), 1845 Converted.flatSize(), 1846 SourceRange(TemplateLoc, RAngleLoc)); 1847 1848 TemplateArgumentList TemplateArgs(Context, Converted, 1849 /*TakeArgs=*/false); 1850 NTTPType = SubstType(NTTPType, 1851 MultiLevelTemplateArgumentList(TemplateArgs), 1852 NTTP->getLocation(), 1853 NTTP->getDeclName()); 1854 // If that worked, check the non-type template parameter type 1855 // for validity. 1856 if (!NTTPType.isNull()) 1857 NTTPType = CheckNonTypeTemplateParameterType(NTTPType, 1858 NTTP->getLocation()); 1859 if (NTTPType.isNull()) 1860 return true; 1861 } 1862 1863 switch (Arg.getArgument().getKind()) { 1864 case TemplateArgument::Null: 1865 assert(false && "Should never see a NULL template argument here"); 1866 return true; 1867 1868 case TemplateArgument::Expression: { 1869 Expr *E = Arg.getArgument().getAsExpr(); 1870 TemplateArgument Result; 1871 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 1872 return true; 1873 1874 Converted.Append(Result); 1875 break; 1876 } 1877 1878 case TemplateArgument::Declaration: 1879 case TemplateArgument::Integral: 1880 // We've already checked this template argument, so just copy 1881 // it to the list of converted arguments. 1882 Converted.Append(Arg.getArgument()); 1883 break; 1884 1885 case TemplateArgument::Template: 1886 // We were given a template template argument. It may not be ill-formed; 1887 // see below. 1888 if (DependentTemplateName *DTN 1889 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) { 1890 // We have a template argument such as \c T::template X, which we 1891 // parsed as a template template argument. However, since we now 1892 // know that we need a non-type template argument, convert this 1893 // template name into an expression. 1894 Expr *E = DependentScopeDeclRefExpr::Create(Context, 1895 DTN->getQualifier(), 1896 Arg.getTemplateQualifierRange(), 1897 DTN->getIdentifier(), 1898 Arg.getTemplateNameLoc()); 1899 1900 TemplateArgument Result; 1901 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 1902 return true; 1903 1904 Converted.Append(Result); 1905 break; 1906 } 1907 1908 // We have a template argument that actually does refer to a class 1909 // template, template alias, or template template parameter, and 1910 // therefore cannot be a non-type template argument. 1911 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) 1912 << Arg.getSourceRange(); 1913 1914 Diag(Param->getLocation(), diag::note_template_param_here); 1915 return true; 1916 1917 case TemplateArgument::Type: { 1918 // We have a non-type template parameter but the template 1919 // argument is a type. 1920 1921 // C++ [temp.arg]p2: 1922 // In a template-argument, an ambiguity between a type-id and 1923 // an expression is resolved to a type-id, regardless of the 1924 // form of the corresponding template-parameter. 1925 // 1926 // We warn specifically about this case, since it can be rather 1927 // confusing for users. 1928 QualType T = Arg.getArgument().getAsType(); 1929 SourceRange SR = Arg.getSourceRange(); 1930 if (T->isFunctionType()) 1931 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; 1932 else 1933 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; 1934 Diag(Param->getLocation(), diag::note_template_param_here); 1935 return true; 1936 } 1937 1938 case TemplateArgument::Pack: 1939 llvm_unreachable("Caller must expand template argument packs"); 1940 break; 1941 } 1942 1943 return false; 1944 } 1945 1946 1947 // Check template template parameters. 1948 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); 1949 1950 // Substitute into the template parameter list of the template 1951 // template parameter, since previously-supplied template arguments 1952 // may appear within the template template parameter. 1953 { 1954 // Set up a template instantiation context. 1955 LocalInstantiationScope Scope(*this); 1956 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 1957 TempParm, Converted.getFlatArguments(), 1958 Converted.flatSize(), 1959 SourceRange(TemplateLoc, RAngleLoc)); 1960 1961 TemplateArgumentList TemplateArgs(Context, Converted, 1962 /*TakeArgs=*/false); 1963 TempParm = cast_or_null<TemplateTemplateParmDecl>( 1964 SubstDecl(TempParm, CurContext, 1965 MultiLevelTemplateArgumentList(TemplateArgs))); 1966 if (!TempParm) 1967 return true; 1968 1969 // FIXME: TempParam is leaked. 1970 } 1971 1972 switch (Arg.getArgument().getKind()) { 1973 case TemplateArgument::Null: 1974 assert(false && "Should never see a NULL template argument here"); 1975 return true; 1976 1977 case TemplateArgument::Template: 1978 if (CheckTemplateArgument(TempParm, Arg)) 1979 return true; 1980 1981 Converted.Append(Arg.getArgument()); 1982 break; 1983 1984 case TemplateArgument::Expression: 1985 case TemplateArgument::Type: 1986 // We have a template template parameter but the template 1987 // argument does not refer to a template. 1988 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template); 1989 return true; 1990 1991 case TemplateArgument::Declaration: 1992 llvm_unreachable( 1993 "Declaration argument with template template parameter"); 1994 break; 1995 case TemplateArgument::Integral: 1996 llvm_unreachable( 1997 "Integral argument with template template parameter"); 1998 break; 1999 2000 case TemplateArgument::Pack: 2001 llvm_unreachable("Caller must expand template argument packs"); 2002 break; 2003 } 2004 2005 return false; 2006} 2007 2008/// \brief Check that the given template argument list is well-formed 2009/// for specializing the given template. 2010bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, 2011 SourceLocation TemplateLoc, 2012 const TemplateArgumentListInfo &TemplateArgs, 2013 bool PartialTemplateArgs, 2014 TemplateArgumentListBuilder &Converted) { 2015 TemplateParameterList *Params = Template->getTemplateParameters(); 2016 unsigned NumParams = Params->size(); 2017 unsigned NumArgs = TemplateArgs.size(); 2018 bool Invalid = false; 2019 2020 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc(); 2021 2022 bool HasParameterPack = 2023 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); 2024 2025 if ((NumArgs > NumParams && !HasParameterPack) || 2026 (NumArgs < Params->getMinRequiredArguments() && 2027 !PartialTemplateArgs)) { 2028 // FIXME: point at either the first arg beyond what we can handle, 2029 // or the '>', depending on whether we have too many or too few 2030 // arguments. 2031 SourceRange Range; 2032 if (NumArgs > NumParams) 2033 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc); 2034 Diag(TemplateLoc, diag::err_template_arg_list_different_arity) 2035 << (NumArgs > NumParams) 2036 << (isa<ClassTemplateDecl>(Template)? 0 : 2037 isa<FunctionTemplateDecl>(Template)? 1 : 2038 isa<TemplateTemplateParmDecl>(Template)? 2 : 3) 2039 << Template << Range; 2040 Diag(Template->getLocation(), diag::note_template_decl_here) 2041 << Params->getSourceRange(); 2042 Invalid = true; 2043 } 2044 2045 // C++ [temp.arg]p1: 2046 // [...] The type and form of each template-argument specified in 2047 // a template-id shall match the type and form specified for the 2048 // corresponding parameter declared by the template in its 2049 // template-parameter-list. 2050 unsigned ArgIdx = 0; 2051 for (TemplateParameterList::iterator Param = Params->begin(), 2052 ParamEnd = Params->end(); 2053 Param != ParamEnd; ++Param, ++ArgIdx) { 2054 if (ArgIdx > NumArgs && PartialTemplateArgs) 2055 break; 2056 2057 // If we have a template parameter pack, check every remaining template 2058 // argument against that template parameter pack. 2059 if ((*Param)->isTemplateParameterPack()) { 2060 Converted.BeginPack(); 2061 for (; ArgIdx < NumArgs; ++ArgIdx) { 2062 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2063 TemplateLoc, RAngleLoc, Converted)) { 2064 Invalid = true; 2065 break; 2066 } 2067 } 2068 Converted.EndPack(); 2069 continue; 2070 } 2071 2072 if (ArgIdx < NumArgs) { 2073 // Check the template argument we were given. 2074 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2075 TemplateLoc, RAngleLoc, Converted)) 2076 return true; 2077 2078 continue; 2079 } 2080 2081 // We have a default template argument that we will use. 2082 TemplateArgumentLoc Arg; 2083 2084 // Retrieve the default template argument from the template 2085 // parameter. For each kind of template parameter, we substitute the 2086 // template arguments provided thus far and any "outer" template arguments 2087 // (when the template parameter was part of a nested template) into 2088 // the default argument. 2089 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { 2090 if (!TTP->hasDefaultArgument()) { 2091 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2092 break; 2093 } 2094 2095 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this, 2096 Template, 2097 TemplateLoc, 2098 RAngleLoc, 2099 TTP, 2100 Converted); 2101 if (!ArgType) 2102 return true; 2103 2104 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), 2105 ArgType); 2106 } else if (NonTypeTemplateParmDecl *NTTP 2107 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { 2108 if (!NTTP->hasDefaultArgument()) { 2109 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2110 break; 2111 } 2112 2113 Sema::OwningExprResult E = SubstDefaultTemplateArgument(*this, Template, 2114 TemplateLoc, 2115 RAngleLoc, 2116 NTTP, 2117 Converted); 2118 if (E.isInvalid()) 2119 return true; 2120 2121 Expr *Ex = E.takeAs<Expr>(); 2122 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); 2123 } else { 2124 TemplateTemplateParmDecl *TempParm 2125 = cast<TemplateTemplateParmDecl>(*Param); 2126 2127 if (!TempParm->hasDefaultArgument()) { 2128 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2129 break; 2130 } 2131 2132 TemplateName Name = SubstDefaultTemplateArgument(*this, Template, 2133 TemplateLoc, 2134 RAngleLoc, 2135 TempParm, 2136 Converted); 2137 if (Name.isNull()) 2138 return true; 2139 2140 Arg = TemplateArgumentLoc(TemplateArgument(Name), 2141 TempParm->getDefaultArgument().getTemplateQualifierRange(), 2142 TempParm->getDefaultArgument().getTemplateNameLoc()); 2143 } 2144 2145 // Introduce an instantiation record that describes where we are using 2146 // the default template argument. 2147 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, 2148 Converted.getFlatArguments(), 2149 Converted.flatSize(), 2150 SourceRange(TemplateLoc, RAngleLoc)); 2151 2152 // Check the default template argument. 2153 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, 2154 RAngleLoc, Converted)) 2155 return true; 2156 } 2157 2158 return Invalid; 2159} 2160 2161/// \brief Check a template argument against its corresponding 2162/// template type parameter. 2163/// 2164/// This routine implements the semantics of C++ [temp.arg.type]. It 2165/// returns true if an error occurred, and false otherwise. 2166bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, 2167 TypeSourceInfo *ArgInfo) { 2168 assert(ArgInfo && "invalid TypeSourceInfo"); 2169 QualType Arg = ArgInfo->getType(); 2170 2171 // C++ [temp.arg.type]p2: 2172 // A local type, a type with no linkage, an unnamed type or a type 2173 // compounded from any of these types shall not be used as a 2174 // template-argument for a template type-parameter. 2175 // 2176 // FIXME: Perform the recursive and no-linkage type checks. 2177 const TagType *Tag = 0; 2178 if (const EnumType *EnumT = Arg->getAs<EnumType>()) 2179 Tag = EnumT; 2180 else if (const RecordType *RecordT = Arg->getAs<RecordType>()) 2181 Tag = RecordT; 2182 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) { 2183 SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange(); 2184 return Diag(SR.getBegin(), diag::err_template_arg_local_type) 2185 << QualType(Tag, 0) << SR; 2186 } else if (Tag && !Tag->getDecl()->getDeclName() && 2187 !Tag->getDecl()->getTypedefForAnonDecl()) { 2188 SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange(); 2189 Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR; 2190 Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here); 2191 return true; 2192 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) { 2193 SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange(); 2194 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR; 2195 } 2196 2197 return false; 2198} 2199 2200/// \brief Checks whether the given template argument is the address 2201/// of an object or function according to C++ [temp.arg.nontype]p1. 2202bool Sema::CheckTemplateArgumentAddressOfObjectOrFunction(Expr *Arg, 2203 NamedDecl *&Entity) { 2204 bool Invalid = false; 2205 2206 // See through any implicit casts we added to fix the type. 2207 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2208 Arg = Cast->getSubExpr(); 2209 2210 // C++0x allows nullptr, and there's no further checking to be done for that. 2211 if (Arg->getType()->isNullPtrType()) 2212 return false; 2213 2214 // C++ [temp.arg.nontype]p1: 2215 // 2216 // A template-argument for a non-type, non-template 2217 // template-parameter shall be one of: [...] 2218 // 2219 // -- the address of an object or function with external 2220 // linkage, including function templates and function 2221 // template-ids but excluding non-static class members, 2222 // expressed as & id-expression where the & is optional if 2223 // the name refers to a function or array, or if the 2224 // corresponding template-parameter is a reference; or 2225 DeclRefExpr *DRE = 0; 2226 2227 // Ignore (and complain about) any excess parentheses. 2228 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2229 if (!Invalid) { 2230 Diag(Arg->getSourceRange().getBegin(), 2231 diag::err_template_arg_extra_parens) 2232 << Arg->getSourceRange(); 2233 Invalid = true; 2234 } 2235 2236 Arg = Parens->getSubExpr(); 2237 } 2238 2239 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2240 if (UnOp->getOpcode() == UnaryOperator::AddrOf) 2241 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2242 } else 2243 DRE = dyn_cast<DeclRefExpr>(Arg); 2244 2245 if (!DRE || !isa<ValueDecl>(DRE->getDecl())) 2246 return Diag(Arg->getSourceRange().getBegin(), 2247 diag::err_template_arg_not_object_or_func_form) 2248 << Arg->getSourceRange(); 2249 2250 // Cannot refer to non-static data members 2251 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) 2252 return Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field) 2253 << Field << Arg->getSourceRange(); 2254 2255 // Cannot refer to non-static member functions 2256 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl())) 2257 if (!Method->isStatic()) 2258 return Diag(Arg->getSourceRange().getBegin(), 2259 diag::err_template_arg_method) 2260 << Method << Arg->getSourceRange(); 2261 2262 // Functions must have external linkage. 2263 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) { 2264 if (Func->getLinkage() != NamedDecl::ExternalLinkage) { 2265 Diag(Arg->getSourceRange().getBegin(), 2266 diag::err_template_arg_function_not_extern) 2267 << Func << Arg->getSourceRange(); 2268 Diag(Func->getLocation(), diag::note_template_arg_internal_object) 2269 << true; 2270 return true; 2271 } 2272 2273 // Okay: we've named a function with external linkage. 2274 Entity = Func; 2275 return Invalid; 2276 } 2277 2278 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 2279 if (Var->getLinkage() != NamedDecl::ExternalLinkage) { 2280 Diag(Arg->getSourceRange().getBegin(), 2281 diag::err_template_arg_object_not_extern) 2282 << Var << Arg->getSourceRange(); 2283 Diag(Var->getLocation(), diag::note_template_arg_internal_object) 2284 << true; 2285 return true; 2286 } 2287 2288 // Okay: we've named an object with external linkage 2289 Entity = Var; 2290 return Invalid; 2291 } 2292 2293 // We found something else, but we don't know specifically what it is. 2294 Diag(Arg->getSourceRange().getBegin(), 2295 diag::err_template_arg_not_object_or_func) 2296 << Arg->getSourceRange(); 2297 Diag(DRE->getDecl()->getLocation(), 2298 diag::note_template_arg_refers_here); 2299 return true; 2300} 2301 2302/// \brief Checks whether the given template argument is a pointer to 2303/// member constant according to C++ [temp.arg.nontype]p1. 2304bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, 2305 TemplateArgument &Converted) { 2306 bool Invalid = false; 2307 2308 // See through any implicit casts we added to fix the type. 2309 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2310 Arg = Cast->getSubExpr(); 2311 2312 // C++0x allows nullptr, and there's no further checking to be done for that. 2313 if (Arg->getType()->isNullPtrType()) 2314 return false; 2315 2316 // C++ [temp.arg.nontype]p1: 2317 // 2318 // A template-argument for a non-type, non-template 2319 // template-parameter shall be one of: [...] 2320 // 2321 // -- a pointer to member expressed as described in 5.3.1. 2322 DeclRefExpr *DRE = 0; 2323 2324 // Ignore (and complain about) any excess parentheses. 2325 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2326 if (!Invalid) { 2327 Diag(Arg->getSourceRange().getBegin(), 2328 diag::err_template_arg_extra_parens) 2329 << Arg->getSourceRange(); 2330 Invalid = true; 2331 } 2332 2333 Arg = Parens->getSubExpr(); 2334 } 2335 2336 // A pointer-to-member constant written &Class::member. 2337 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2338 if (UnOp->getOpcode() == UnaryOperator::AddrOf) { 2339 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2340 if (DRE && !DRE->getQualifier()) 2341 DRE = 0; 2342 } 2343 } 2344 // A constant of pointer-to-member type. 2345 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { 2346 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { 2347 if (VD->getType()->isMemberPointerType()) { 2348 if (isa<NonTypeTemplateParmDecl>(VD) || 2349 (isa<VarDecl>(VD) && 2350 Context.getCanonicalType(VD->getType()).isConstQualified())) { 2351 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2352 Converted = TemplateArgument(Arg->Retain()); 2353 else 2354 Converted = TemplateArgument(VD->getCanonicalDecl()); 2355 return Invalid; 2356 } 2357 } 2358 } 2359 2360 DRE = 0; 2361 } 2362 2363 if (!DRE) 2364 return Diag(Arg->getSourceRange().getBegin(), 2365 diag::err_template_arg_not_pointer_to_member_form) 2366 << Arg->getSourceRange(); 2367 2368 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { 2369 assert((isa<FieldDecl>(DRE->getDecl()) || 2370 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && 2371 "Only non-static member pointers can make it here"); 2372 2373 // Okay: this is the address of a non-static member, and therefore 2374 // a member pointer constant. 2375 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2376 Converted = TemplateArgument(Arg->Retain()); 2377 else 2378 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); 2379 return Invalid; 2380 } 2381 2382 // We found something else, but we don't know specifically what it is. 2383 Diag(Arg->getSourceRange().getBegin(), 2384 diag::err_template_arg_not_pointer_to_member_form) 2385 << Arg->getSourceRange(); 2386 Diag(DRE->getDecl()->getLocation(), 2387 diag::note_template_arg_refers_here); 2388 return true; 2389} 2390 2391/// \brief Check a template argument against its corresponding 2392/// non-type template parameter. 2393/// 2394/// This routine implements the semantics of C++ [temp.arg.nontype]. 2395/// It returns true if an error occurred, and false otherwise. \p 2396/// InstantiatedParamType is the type of the non-type template 2397/// parameter after it has been instantiated. 2398/// 2399/// If no error was detected, Converted receives the converted template argument. 2400bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, 2401 QualType InstantiatedParamType, Expr *&Arg, 2402 TemplateArgument &Converted) { 2403 SourceLocation StartLoc = Arg->getSourceRange().getBegin(); 2404 2405 // If either the parameter has a dependent type or the argument is 2406 // type-dependent, there's nothing we can check now. 2407 // FIXME: Add template argument to Converted! 2408 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { 2409 // FIXME: Produce a cloned, canonical expression? 2410 Converted = TemplateArgument(Arg); 2411 return false; 2412 } 2413 2414 // C++ [temp.arg.nontype]p5: 2415 // The following conversions are performed on each expression used 2416 // as a non-type template-argument. If a non-type 2417 // template-argument cannot be converted to the type of the 2418 // corresponding template-parameter then the program is 2419 // ill-formed. 2420 // 2421 // -- for a non-type template-parameter of integral or 2422 // enumeration type, integral promotions (4.5) and integral 2423 // conversions (4.7) are applied. 2424 QualType ParamType = InstantiatedParamType; 2425 QualType ArgType = Arg->getType(); 2426 if (ParamType->isIntegralType() || ParamType->isEnumeralType()) { 2427 // C++ [temp.arg.nontype]p1: 2428 // A template-argument for a non-type, non-template 2429 // template-parameter shall be one of: 2430 // 2431 // -- an integral constant-expression of integral or enumeration 2432 // type; or 2433 // -- the name of a non-type template-parameter; or 2434 SourceLocation NonConstantLoc; 2435 llvm::APSInt Value; 2436 if (!ArgType->isIntegralType() && !ArgType->isEnumeralType()) { 2437 Diag(Arg->getSourceRange().getBegin(), 2438 diag::err_template_arg_not_integral_or_enumeral) 2439 << ArgType << Arg->getSourceRange(); 2440 Diag(Param->getLocation(), diag::note_template_param_here); 2441 return true; 2442 } else if (!Arg->isValueDependent() && 2443 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) { 2444 Diag(NonConstantLoc, diag::err_template_arg_not_ice) 2445 << ArgType << Arg->getSourceRange(); 2446 return true; 2447 } 2448 2449 // FIXME: We need some way to more easily get the unqualified form 2450 // of the types without going all the way to the 2451 // canonical type. 2452 if (Context.getCanonicalType(ParamType).getCVRQualifiers()) 2453 ParamType = Context.getCanonicalType(ParamType).getUnqualifiedType(); 2454 if (Context.getCanonicalType(ArgType).getCVRQualifiers()) 2455 ArgType = Context.getCanonicalType(ArgType).getUnqualifiedType(); 2456 2457 // Try to convert the argument to the parameter's type. 2458 if (Context.hasSameType(ParamType, ArgType)) { 2459 // Okay: no conversion necessary 2460 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || 2461 !ParamType->isEnumeralType()) { 2462 // This is an integral promotion or conversion. 2463 ImpCastExprToType(Arg, ParamType, CastExpr::CK_IntegralCast); 2464 } else { 2465 // We can't perform this conversion. 2466 Diag(Arg->getSourceRange().getBegin(), 2467 diag::err_template_arg_not_convertible) 2468 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2469 Diag(Param->getLocation(), diag::note_template_param_here); 2470 return true; 2471 } 2472 2473 QualType IntegerType = Context.getCanonicalType(ParamType); 2474 if (const EnumType *Enum = IntegerType->getAs<EnumType>()) 2475 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); 2476 2477 if (!Arg->isValueDependent()) { 2478 // Check that an unsigned parameter does not receive a negative 2479 // value. 2480 if (IntegerType->isUnsignedIntegerType() 2481 && (Value.isSigned() && Value.isNegative())) { 2482 Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_negative) 2483 << Value.toString(10) << Param->getType() 2484 << Arg->getSourceRange(); 2485 Diag(Param->getLocation(), diag::note_template_param_here); 2486 return true; 2487 } 2488 2489 // Check that we don't overflow the template parameter type. 2490 unsigned AllowedBits = Context.getTypeSize(IntegerType); 2491 unsigned RequiredBits; 2492 if (IntegerType->isUnsignedIntegerType()) 2493 RequiredBits = Value.getActiveBits(); 2494 else if (Value.isUnsigned()) 2495 RequiredBits = Value.getActiveBits() + 1; 2496 else 2497 RequiredBits = Value.getMinSignedBits(); 2498 if (RequiredBits > AllowedBits) { 2499 Diag(Arg->getSourceRange().getBegin(), 2500 diag::err_template_arg_too_large) 2501 << Value.toString(10) << Param->getType() 2502 << Arg->getSourceRange(); 2503 Diag(Param->getLocation(), diag::note_template_param_here); 2504 return true; 2505 } 2506 2507 if (Value.getBitWidth() != AllowedBits) 2508 Value.extOrTrunc(AllowedBits); 2509 Value.setIsSigned(IntegerType->isSignedIntegerType()); 2510 } 2511 2512 // Add the value of this argument to the list of converted 2513 // arguments. We use the bitwidth and signedness of the template 2514 // parameter. 2515 if (Arg->isValueDependent()) { 2516 // The argument is value-dependent. Create a new 2517 // TemplateArgument with the converted expression. 2518 Converted = TemplateArgument(Arg); 2519 return false; 2520 } 2521 2522 Converted = TemplateArgument(Value, 2523 ParamType->isEnumeralType() ? ParamType 2524 : IntegerType); 2525 return false; 2526 } 2527 2528 // Handle pointer-to-function, reference-to-function, and 2529 // pointer-to-member-function all in (roughly) the same way. 2530 if (// -- For a non-type template-parameter of type pointer to 2531 // function, only the function-to-pointer conversion (4.3) is 2532 // applied. If the template-argument represents a set of 2533 // overloaded functions (or a pointer to such), the matching 2534 // function is selected from the set (13.4). 2535 // In C++0x, any std::nullptr_t value can be converted. 2536 (ParamType->isPointerType() && 2537 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || 2538 // -- For a non-type template-parameter of type reference to 2539 // function, no conversions apply. If the template-argument 2540 // represents a set of overloaded functions, the matching 2541 // function is selected from the set (13.4). 2542 (ParamType->isReferenceType() && 2543 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || 2544 // -- For a non-type template-parameter of type pointer to 2545 // member function, no conversions apply. If the 2546 // template-argument represents a set of overloaded member 2547 // functions, the matching member function is selected from 2548 // the set (13.4). 2549 // Again, C++0x allows a std::nullptr_t value. 2550 (ParamType->isMemberPointerType() && 2551 ParamType->getAs<MemberPointerType>()->getPointeeType() 2552 ->isFunctionType())) { 2553 if (Context.hasSameUnqualifiedType(ArgType, 2554 ParamType.getNonReferenceType())) { 2555 // We don't have to do anything: the types already match. 2556 } else if (ArgType->isNullPtrType() && (ParamType->isPointerType() || 2557 ParamType->isMemberPointerType())) { 2558 ArgType = ParamType; 2559 if (ParamType->isMemberPointerType()) 2560 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NullToMemberPointer); 2561 else 2562 ImpCastExprToType(Arg, ParamType, CastExpr::CK_BitCast); 2563 } else if (ArgType->isFunctionType() && ParamType->isPointerType()) { 2564 ArgType = Context.getPointerType(ArgType); 2565 ImpCastExprToType(Arg, ArgType, CastExpr::CK_FunctionToPointerDecay); 2566 } else if (FunctionDecl *Fn 2567 = ResolveAddressOfOverloadedFunction(Arg, ParamType, true)) { 2568 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2569 return true; 2570 2571 Arg = FixOverloadedFunctionReference(Arg, Fn); 2572 ArgType = Arg->getType(); 2573 if (ArgType->isFunctionType() && ParamType->isPointerType()) { 2574 ArgType = Context.getPointerType(Arg->getType()); 2575 ImpCastExprToType(Arg, ArgType, CastExpr::CK_FunctionToPointerDecay); 2576 } 2577 } 2578 2579 if (!Context.hasSameUnqualifiedType(ArgType, 2580 ParamType.getNonReferenceType())) { 2581 // We can't perform this conversion. 2582 Diag(Arg->getSourceRange().getBegin(), 2583 diag::err_template_arg_not_convertible) 2584 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2585 Diag(Param->getLocation(), diag::note_template_param_here); 2586 return true; 2587 } 2588 2589 if (ParamType->isMemberPointerType()) 2590 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2591 2592 NamedDecl *Entity = 0; 2593 if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity)) 2594 return true; 2595 2596 if (Entity) 2597 Entity = cast<NamedDecl>(Entity->getCanonicalDecl()); 2598 Converted = TemplateArgument(Entity); 2599 return false; 2600 } 2601 2602 if (ParamType->isPointerType()) { 2603 // -- for a non-type template-parameter of type pointer to 2604 // object, qualification conversions (4.4) and the 2605 // array-to-pointer conversion (4.2) are applied. 2606 // C++0x also allows a value of std::nullptr_t. 2607 assert(ParamType->getAs<PointerType>()->getPointeeType()->isObjectType() && 2608 "Only object pointers allowed here"); 2609 2610 if (ArgType->isNullPtrType()) { 2611 ArgType = ParamType; 2612 ImpCastExprToType(Arg, ParamType, CastExpr::CK_BitCast); 2613 } else if (ArgType->isArrayType()) { 2614 ArgType = Context.getArrayDecayedType(ArgType); 2615 ImpCastExprToType(Arg, ArgType, CastExpr::CK_ArrayToPointerDecay); 2616 } 2617 2618 if (IsQualificationConversion(ArgType, ParamType)) { 2619 ArgType = ParamType; 2620 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp); 2621 } 2622 2623 if (!Context.hasSameUnqualifiedType(ArgType, ParamType)) { 2624 // We can't perform this conversion. 2625 Diag(Arg->getSourceRange().getBegin(), 2626 diag::err_template_arg_not_convertible) 2627 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2628 Diag(Param->getLocation(), diag::note_template_param_here); 2629 return true; 2630 } 2631 2632 NamedDecl *Entity = 0; 2633 if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity)) 2634 return true; 2635 2636 if (Entity) 2637 Entity = cast<NamedDecl>(Entity->getCanonicalDecl()); 2638 Converted = TemplateArgument(Entity); 2639 return false; 2640 } 2641 2642 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { 2643 // -- For a non-type template-parameter of type reference to 2644 // object, no conversions apply. The type referred to by the 2645 // reference may be more cv-qualified than the (otherwise 2646 // identical) type of the template-argument. The 2647 // template-parameter is bound directly to the 2648 // template-argument, which must be an lvalue. 2649 assert(ParamRefType->getPointeeType()->isObjectType() && 2650 "Only object references allowed here"); 2651 2652 if (!Context.hasSameUnqualifiedType(ParamRefType->getPointeeType(), ArgType)) { 2653 Diag(Arg->getSourceRange().getBegin(), 2654 diag::err_template_arg_no_ref_bind) 2655 << InstantiatedParamType << Arg->getType() 2656 << Arg->getSourceRange(); 2657 Diag(Param->getLocation(), diag::note_template_param_here); 2658 return true; 2659 } 2660 2661 unsigned ParamQuals 2662 = Context.getCanonicalType(ParamType).getCVRQualifiers(); 2663 unsigned ArgQuals = Context.getCanonicalType(ArgType).getCVRQualifiers(); 2664 2665 if ((ParamQuals | ArgQuals) != ParamQuals) { 2666 Diag(Arg->getSourceRange().getBegin(), 2667 diag::err_template_arg_ref_bind_ignores_quals) 2668 << InstantiatedParamType << Arg->getType() 2669 << Arg->getSourceRange(); 2670 Diag(Param->getLocation(), diag::note_template_param_here); 2671 return true; 2672 } 2673 2674 NamedDecl *Entity = 0; 2675 if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity)) 2676 return true; 2677 2678 Entity = cast<NamedDecl>(Entity->getCanonicalDecl()); 2679 Converted = TemplateArgument(Entity); 2680 return false; 2681 } 2682 2683 // -- For a non-type template-parameter of type pointer to data 2684 // member, qualification conversions (4.4) are applied. 2685 // C++0x allows std::nullptr_t values. 2686 assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); 2687 2688 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) { 2689 // Types match exactly: nothing more to do here. 2690 } else if (ArgType->isNullPtrType()) { 2691 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NullToMemberPointer); 2692 } else if (IsQualificationConversion(ArgType, ParamType)) { 2693 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp); 2694 } else { 2695 // We can't perform this conversion. 2696 Diag(Arg->getSourceRange().getBegin(), 2697 diag::err_template_arg_not_convertible) 2698 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2699 Diag(Param->getLocation(), diag::note_template_param_here); 2700 return true; 2701 } 2702 2703 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2704} 2705 2706/// \brief Check a template argument against its corresponding 2707/// template template parameter. 2708/// 2709/// This routine implements the semantics of C++ [temp.arg.template]. 2710/// It returns true if an error occurred, and false otherwise. 2711bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, 2712 const TemplateArgumentLoc &Arg) { 2713 TemplateName Name = Arg.getArgument().getAsTemplate(); 2714 TemplateDecl *Template = Name.getAsTemplateDecl(); 2715 if (!Template) { 2716 // Any dependent template name is fine. 2717 assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); 2718 return false; 2719 } 2720 2721 // C++ [temp.arg.template]p1: 2722 // A template-argument for a template template-parameter shall be 2723 // the name of a class template, expressed as id-expression. Only 2724 // primary class templates are considered when matching the 2725 // template template argument with the corresponding parameter; 2726 // partial specializations are not considered even if their 2727 // parameter lists match that of the template template parameter. 2728 // 2729 // Note that we also allow template template parameters here, which 2730 // will happen when we are dealing with, e.g., class template 2731 // partial specializations. 2732 if (!isa<ClassTemplateDecl>(Template) && 2733 !isa<TemplateTemplateParmDecl>(Template)) { 2734 assert(isa<FunctionTemplateDecl>(Template) && 2735 "Only function templates are possible here"); 2736 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); 2737 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) 2738 << Template; 2739 } 2740 2741 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), 2742 Param->getTemplateParameters(), 2743 true, 2744 TPL_TemplateTemplateArgumentMatch, 2745 Arg.getLocation()); 2746} 2747 2748/// \brief Determine whether the given template parameter lists are 2749/// equivalent. 2750/// 2751/// \param New The new template parameter list, typically written in the 2752/// source code as part of a new template declaration. 2753/// 2754/// \param Old The old template parameter list, typically found via 2755/// name lookup of the template declared with this template parameter 2756/// list. 2757/// 2758/// \param Complain If true, this routine will produce a diagnostic if 2759/// the template parameter lists are not equivalent. 2760/// 2761/// \param Kind describes how we are to match the template parameter lists. 2762/// 2763/// \param TemplateArgLoc If this source location is valid, then we 2764/// are actually checking the template parameter list of a template 2765/// argument (New) against the template parameter list of its 2766/// corresponding template template parameter (Old). We produce 2767/// slightly different diagnostics in this scenario. 2768/// 2769/// \returns True if the template parameter lists are equal, false 2770/// otherwise. 2771bool 2772Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, 2773 TemplateParameterList *Old, 2774 bool Complain, 2775 TemplateParameterListEqualKind Kind, 2776 SourceLocation TemplateArgLoc) { 2777 if (Old->size() != New->size()) { 2778 if (Complain) { 2779 unsigned NextDiag = diag::err_template_param_list_different_arity; 2780 if (TemplateArgLoc.isValid()) { 2781 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 2782 NextDiag = diag::note_template_param_list_different_arity; 2783 } 2784 Diag(New->getTemplateLoc(), NextDiag) 2785 << (New->size() > Old->size()) 2786 << (Kind != TPL_TemplateMatch) 2787 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); 2788 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) 2789 << (Kind != TPL_TemplateMatch) 2790 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); 2791 } 2792 2793 return false; 2794 } 2795 2796 for (TemplateParameterList::iterator OldParm = Old->begin(), 2797 OldParmEnd = Old->end(), NewParm = New->begin(); 2798 OldParm != OldParmEnd; ++OldParm, ++NewParm) { 2799 if ((*OldParm)->getKind() != (*NewParm)->getKind()) { 2800 if (Complain) { 2801 unsigned NextDiag = diag::err_template_param_different_kind; 2802 if (TemplateArgLoc.isValid()) { 2803 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 2804 NextDiag = diag::note_template_param_different_kind; 2805 } 2806 Diag((*NewParm)->getLocation(), NextDiag) 2807 << (Kind != TPL_TemplateMatch); 2808 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration) 2809 << (Kind != TPL_TemplateMatch); 2810 } 2811 return false; 2812 } 2813 2814 if (isa<TemplateTypeParmDecl>(*OldParm)) { 2815 // Okay; all template type parameters are equivalent (since we 2816 // know we're at the same index). 2817 } else if (NonTypeTemplateParmDecl *OldNTTP 2818 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) { 2819 // The types of non-type template parameters must agree. 2820 NonTypeTemplateParmDecl *NewNTTP 2821 = cast<NonTypeTemplateParmDecl>(*NewParm); 2822 2823 // If we are matching a template template argument to a template 2824 // template parameter and one of the non-type template parameter types 2825 // is dependent, then we must wait until template instantiation time 2826 // to actually compare the arguments. 2827 if (Kind == TPL_TemplateTemplateArgumentMatch && 2828 (OldNTTP->getType()->isDependentType() || 2829 NewNTTP->getType()->isDependentType())) 2830 continue; 2831 2832 if (Context.getCanonicalType(OldNTTP->getType()) != 2833 Context.getCanonicalType(NewNTTP->getType())) { 2834 if (Complain) { 2835 unsigned NextDiag = diag::err_template_nontype_parm_different_type; 2836 if (TemplateArgLoc.isValid()) { 2837 Diag(TemplateArgLoc, 2838 diag::err_template_arg_template_params_mismatch); 2839 NextDiag = diag::note_template_nontype_parm_different_type; 2840 } 2841 Diag(NewNTTP->getLocation(), NextDiag) 2842 << NewNTTP->getType() 2843 << (Kind != TPL_TemplateMatch); 2844 Diag(OldNTTP->getLocation(), 2845 diag::note_template_nontype_parm_prev_declaration) 2846 << OldNTTP->getType(); 2847 } 2848 return false; 2849 } 2850 } else { 2851 // The template parameter lists of template template 2852 // parameters must agree. 2853 assert(isa<TemplateTemplateParmDecl>(*OldParm) && 2854 "Only template template parameters handled here"); 2855 TemplateTemplateParmDecl *OldTTP 2856 = cast<TemplateTemplateParmDecl>(*OldParm); 2857 TemplateTemplateParmDecl *NewTTP 2858 = cast<TemplateTemplateParmDecl>(*NewParm); 2859 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), 2860 OldTTP->getTemplateParameters(), 2861 Complain, 2862 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind), 2863 TemplateArgLoc)) 2864 return false; 2865 } 2866 } 2867 2868 return true; 2869} 2870 2871/// \brief Check whether a template can be declared within this scope. 2872/// 2873/// If the template declaration is valid in this scope, returns 2874/// false. Otherwise, issues a diagnostic and returns true. 2875bool 2876Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { 2877 // Find the nearest enclosing declaration scope. 2878 while ((S->getFlags() & Scope::DeclScope) == 0 || 2879 (S->getFlags() & Scope::TemplateParamScope) != 0) 2880 S = S->getParent(); 2881 2882 // C++ [temp]p2: 2883 // A template-declaration can appear only as a namespace scope or 2884 // class scope declaration. 2885 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 2886 if (Ctx && isa<LinkageSpecDecl>(Ctx) && 2887 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) 2888 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) 2889 << TemplateParams->getSourceRange(); 2890 2891 while (Ctx && isa<LinkageSpecDecl>(Ctx)) 2892 Ctx = Ctx->getParent(); 2893 2894 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) 2895 return false; 2896 2897 return Diag(TemplateParams->getTemplateLoc(), 2898 diag::err_template_outside_namespace_or_class_scope) 2899 << TemplateParams->getSourceRange(); 2900} 2901 2902/// \brief Determine what kind of template specialization the given declaration 2903/// is. 2904static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) { 2905 if (!D) 2906 return TSK_Undeclared; 2907 2908 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) 2909 return Record->getTemplateSpecializationKind(); 2910 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) 2911 return Function->getTemplateSpecializationKind(); 2912 if (VarDecl *Var = dyn_cast<VarDecl>(D)) 2913 return Var->getTemplateSpecializationKind(); 2914 2915 return TSK_Undeclared; 2916} 2917 2918/// \brief Check whether a specialization is well-formed in the current 2919/// context. 2920/// 2921/// This routine determines whether a template specialization can be declared 2922/// in the current context (C++ [temp.expl.spec]p2). 2923/// 2924/// \param S the semantic analysis object for which this check is being 2925/// performed. 2926/// 2927/// \param Specialized the entity being specialized or instantiated, which 2928/// may be a kind of template (class template, function template, etc.) or 2929/// a member of a class template (member function, static data member, 2930/// member class). 2931/// 2932/// \param PrevDecl the previous declaration of this entity, if any. 2933/// 2934/// \param Loc the location of the explicit specialization or instantiation of 2935/// this entity. 2936/// 2937/// \param IsPartialSpecialization whether this is a partial specialization of 2938/// a class template. 2939/// 2940/// \returns true if there was an error that we cannot recover from, false 2941/// otherwise. 2942static bool CheckTemplateSpecializationScope(Sema &S, 2943 NamedDecl *Specialized, 2944 NamedDecl *PrevDecl, 2945 SourceLocation Loc, 2946 bool IsPartialSpecialization) { 2947 // Keep these "kind" numbers in sync with the %select statements in the 2948 // various diagnostics emitted by this routine. 2949 int EntityKind = 0; 2950 bool isTemplateSpecialization = false; 2951 if (isa<ClassTemplateDecl>(Specialized)) { 2952 EntityKind = IsPartialSpecialization? 1 : 0; 2953 isTemplateSpecialization = true; 2954 } else if (isa<FunctionTemplateDecl>(Specialized)) { 2955 EntityKind = 2; 2956 isTemplateSpecialization = true; 2957 } else if (isa<CXXMethodDecl>(Specialized)) 2958 EntityKind = 3; 2959 else if (isa<VarDecl>(Specialized)) 2960 EntityKind = 4; 2961 else if (isa<RecordDecl>(Specialized)) 2962 EntityKind = 5; 2963 else { 2964 S.Diag(Loc, diag::err_template_spec_unknown_kind); 2965 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 2966 return true; 2967 } 2968 2969 // C++ [temp.expl.spec]p2: 2970 // An explicit specialization shall be declared in the namespace 2971 // of which the template is a member, or, for member templates, in 2972 // the namespace of which the enclosing class or enclosing class 2973 // template is a member. An explicit specialization of a member 2974 // function, member class or static data member of a class 2975 // template shall be declared in the namespace of which the class 2976 // template is a member. Such a declaration may also be a 2977 // definition. If the declaration is not a definition, the 2978 // specialization may be defined later in the name- space in which 2979 // the explicit specialization was declared, or in a namespace 2980 // that encloses the one in which the explicit specialization was 2981 // declared. 2982 if (S.CurContext->getLookupContext()->isFunctionOrMethod()) { 2983 S.Diag(Loc, diag::err_template_spec_decl_function_scope) 2984 << Specialized; 2985 return true; 2986 } 2987 2988 if (S.CurContext->isRecord() && !IsPartialSpecialization) { 2989 S.Diag(Loc, diag::err_template_spec_decl_class_scope) 2990 << Specialized; 2991 return true; 2992 } 2993 2994 // C++ [temp.class.spec]p6: 2995 // A class template partial specialization may be declared or redeclared 2996 // in any namespace scope in which its definition may be defined (14.5.1 2997 // and 14.5.2). 2998 bool ComplainedAboutScope = false; 2999 DeclContext *SpecializedContext 3000 = Specialized->getDeclContext()->getEnclosingNamespaceContext(); 3001 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); 3002 if ((!PrevDecl || 3003 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || 3004 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ 3005 // There is no prior declaration of this entity, so this 3006 // specialization must be in the same context as the template 3007 // itself. 3008 if (!DC->Equals(SpecializedContext)) { 3009 if (isa<TranslationUnitDecl>(SpecializedContext)) 3010 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) 3011 << EntityKind << Specialized; 3012 else if (isa<NamespaceDecl>(SpecializedContext)) 3013 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope) 3014 << EntityKind << Specialized 3015 << cast<NamedDecl>(SpecializedContext); 3016 3017 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3018 ComplainedAboutScope = true; 3019 } 3020 } 3021 3022 // Make sure that this redeclaration (or definition) occurs in an enclosing 3023 // namespace. 3024 // Note that HandleDeclarator() performs this check for explicit 3025 // specializations of function templates, static data members, and member 3026 // functions, so we skip the check here for those kinds of entities. 3027 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. 3028 // Should we refactor that check, so that it occurs later? 3029 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && 3030 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || 3031 isa<FunctionDecl>(Specialized))) { 3032 if (isa<TranslationUnitDecl>(SpecializedContext)) 3033 S.Diag(Loc, diag::err_template_spec_redecl_global_scope) 3034 << EntityKind << Specialized; 3035 else if (isa<NamespaceDecl>(SpecializedContext)) 3036 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) 3037 << EntityKind << Specialized 3038 << cast<NamedDecl>(SpecializedContext); 3039 3040 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3041 } 3042 3043 // FIXME: check for specialization-after-instantiation errors and such. 3044 3045 return false; 3046} 3047 3048/// \brief Check the non-type template arguments of a class template 3049/// partial specialization according to C++ [temp.class.spec]p9. 3050/// 3051/// \param TemplateParams the template parameters of the primary class 3052/// template. 3053/// 3054/// \param TemplateArg the template arguments of the class template 3055/// partial specialization. 3056/// 3057/// \param MirrorsPrimaryTemplate will be set true if the class 3058/// template partial specialization arguments are identical to the 3059/// implicit template arguments of the primary template. This is not 3060/// necessarily an error (C++0x), and it is left to the caller to diagnose 3061/// this condition when it is an error. 3062/// 3063/// \returns true if there was an error, false otherwise. 3064bool Sema::CheckClassTemplatePartialSpecializationArgs( 3065 TemplateParameterList *TemplateParams, 3066 const TemplateArgumentListBuilder &TemplateArgs, 3067 bool &MirrorsPrimaryTemplate) { 3068 // FIXME: the interface to this function will have to change to 3069 // accommodate variadic templates. 3070 MirrorsPrimaryTemplate = true; 3071 3072 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments(); 3073 3074 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3075 // Determine whether the template argument list of the partial 3076 // specialization is identical to the implicit argument list of 3077 // the primary template. The caller may need to diagnostic this as 3078 // an error per C++ [temp.class.spec]p9b3. 3079 if (MirrorsPrimaryTemplate) { 3080 if (TemplateTypeParmDecl *TTP 3081 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) { 3082 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) != 3083 Context.getCanonicalType(ArgList[I].getAsType())) 3084 MirrorsPrimaryTemplate = false; 3085 } else if (TemplateTemplateParmDecl *TTP 3086 = dyn_cast<TemplateTemplateParmDecl>( 3087 TemplateParams->getParam(I))) { 3088 TemplateName Name = ArgList[I].getAsTemplate(); 3089 TemplateTemplateParmDecl *ArgDecl 3090 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()); 3091 if (!ArgDecl || 3092 ArgDecl->getIndex() != TTP->getIndex() || 3093 ArgDecl->getDepth() != TTP->getDepth()) 3094 MirrorsPrimaryTemplate = false; 3095 } 3096 } 3097 3098 NonTypeTemplateParmDecl *Param 3099 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); 3100 if (!Param) { 3101 continue; 3102 } 3103 3104 Expr *ArgExpr = ArgList[I].getAsExpr(); 3105 if (!ArgExpr) { 3106 MirrorsPrimaryTemplate = false; 3107 continue; 3108 } 3109 3110 // C++ [temp.class.spec]p8: 3111 // A non-type argument is non-specialized if it is the name of a 3112 // non-type parameter. All other non-type arguments are 3113 // specialized. 3114 // 3115 // Below, we check the two conditions that only apply to 3116 // specialized non-type arguments, so skip any non-specialized 3117 // arguments. 3118 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) 3119 if (NonTypeTemplateParmDecl *NTTP 3120 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) { 3121 if (MirrorsPrimaryTemplate && 3122 (Param->getIndex() != NTTP->getIndex() || 3123 Param->getDepth() != NTTP->getDepth())) 3124 MirrorsPrimaryTemplate = false; 3125 3126 continue; 3127 } 3128 3129 // C++ [temp.class.spec]p9: 3130 // Within the argument list of a class template partial 3131 // specialization, the following restrictions apply: 3132 // -- A partially specialized non-type argument expression 3133 // shall not involve a template parameter of the partial 3134 // specialization except when the argument expression is a 3135 // simple identifier. 3136 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { 3137 Diag(ArgExpr->getLocStart(), 3138 diag::err_dependent_non_type_arg_in_partial_spec) 3139 << ArgExpr->getSourceRange(); 3140 return true; 3141 } 3142 3143 // -- The type of a template parameter corresponding to a 3144 // specialized non-type argument shall not be dependent on a 3145 // parameter of the specialization. 3146 if (Param->getType()->isDependentType()) { 3147 Diag(ArgExpr->getLocStart(), 3148 diag::err_dependent_typed_non_type_arg_in_partial_spec) 3149 << Param->getType() 3150 << ArgExpr->getSourceRange(); 3151 Diag(Param->getLocation(), diag::note_template_param_here); 3152 return true; 3153 } 3154 3155 MirrorsPrimaryTemplate = false; 3156 } 3157 3158 return false; 3159} 3160 3161Sema::DeclResult 3162Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, 3163 TagUseKind TUK, 3164 SourceLocation KWLoc, 3165 const CXXScopeSpec &SS, 3166 TemplateTy TemplateD, 3167 SourceLocation TemplateNameLoc, 3168 SourceLocation LAngleLoc, 3169 ASTTemplateArgsPtr TemplateArgsIn, 3170 SourceLocation RAngleLoc, 3171 AttributeList *Attr, 3172 MultiTemplateParamsArg TemplateParameterLists) { 3173 assert(TUK != TUK_Reference && "References are not specializations"); 3174 3175 // Find the class template we're specializing 3176 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 3177 ClassTemplateDecl *ClassTemplate 3178 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); 3179 3180 if (!ClassTemplate) { 3181 Diag(TemplateNameLoc, diag::err_not_class_template_specialization) 3182 << (Name.getAsTemplateDecl() && 3183 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); 3184 return true; 3185 } 3186 3187 bool isExplicitSpecialization = false; 3188 bool isPartialSpecialization = false; 3189 3190 // Check the validity of the template headers that introduce this 3191 // template. 3192 // FIXME: We probably shouldn't complain about these headers for 3193 // friend declarations. 3194 TemplateParameterList *TemplateParams 3195 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS, 3196 (TemplateParameterList**)TemplateParameterLists.get(), 3197 TemplateParameterLists.size(), 3198 isExplicitSpecialization); 3199 if (TemplateParams && TemplateParams->size() > 0) { 3200 isPartialSpecialization = true; 3201 3202 // C++ [temp.class.spec]p10: 3203 // The template parameter list of a specialization shall not 3204 // contain default template argument values. 3205 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3206 Decl *Param = TemplateParams->getParam(I); 3207 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { 3208 if (TTP->hasDefaultArgument()) { 3209 Diag(TTP->getDefaultArgumentLoc(), 3210 diag::err_default_arg_in_partial_spec); 3211 TTP->removeDefaultArgument(); 3212 } 3213 } else if (NonTypeTemplateParmDecl *NTTP 3214 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 3215 if (Expr *DefArg = NTTP->getDefaultArgument()) { 3216 Diag(NTTP->getDefaultArgumentLoc(), 3217 diag::err_default_arg_in_partial_spec) 3218 << DefArg->getSourceRange(); 3219 NTTP->setDefaultArgument(0); 3220 DefArg->Destroy(Context); 3221 } 3222 } else { 3223 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); 3224 if (TTP->hasDefaultArgument()) { 3225 Diag(TTP->getDefaultArgument().getLocation(), 3226 diag::err_default_arg_in_partial_spec) 3227 << TTP->getDefaultArgument().getSourceRange(); 3228 TTP->setDefaultArgument(TemplateArgumentLoc()); 3229 } 3230 } 3231 } 3232 } else if (TemplateParams) { 3233 if (TUK == TUK_Friend) 3234 Diag(KWLoc, diag::err_template_spec_friend) 3235 << CodeModificationHint::CreateRemoval( 3236 SourceRange(TemplateParams->getTemplateLoc(), 3237 TemplateParams->getRAngleLoc())) 3238 << SourceRange(LAngleLoc, RAngleLoc); 3239 else 3240 isExplicitSpecialization = true; 3241 } else if (TUK != TUK_Friend) { 3242 Diag(KWLoc, diag::err_template_spec_needs_header) 3243 << CodeModificationHint::CreateInsertion(KWLoc, "template<> "); 3244 isExplicitSpecialization = true; 3245 } 3246 3247 // Check that the specialization uses the same tag kind as the 3248 // original template. 3249 TagDecl::TagKind Kind; 3250 switch (TagSpec) { 3251 default: assert(0 && "Unknown tag type!"); 3252 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3253 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3254 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3255 } 3256 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 3257 Kind, KWLoc, 3258 *ClassTemplate->getIdentifier())) { 3259 Diag(KWLoc, diag::err_use_with_wrong_tag) 3260 << ClassTemplate 3261 << CodeModificationHint::CreateReplacement(KWLoc, 3262 ClassTemplate->getTemplatedDecl()->getKindName()); 3263 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 3264 diag::note_previous_use); 3265 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 3266 } 3267 3268 // Translate the parser's template argument list in our AST format. 3269 TemplateArgumentListInfo TemplateArgs; 3270 TemplateArgs.setLAngleLoc(LAngleLoc); 3271 TemplateArgs.setRAngleLoc(RAngleLoc); 3272 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 3273 3274 // Check that the template argument list is well-formed for this 3275 // template. 3276 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 3277 TemplateArgs.size()); 3278 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 3279 TemplateArgs, false, Converted)) 3280 return true; 3281 3282 assert((Converted.structuredSize() == 3283 ClassTemplate->getTemplateParameters()->size()) && 3284 "Converted template argument list is too short!"); 3285 3286 // Find the class template (partial) specialization declaration that 3287 // corresponds to these arguments. 3288 llvm::FoldingSetNodeID ID; 3289 if (isPartialSpecialization) { 3290 bool MirrorsPrimaryTemplate; 3291 if (CheckClassTemplatePartialSpecializationArgs( 3292 ClassTemplate->getTemplateParameters(), 3293 Converted, MirrorsPrimaryTemplate)) 3294 return true; 3295 3296 if (MirrorsPrimaryTemplate) { 3297 // C++ [temp.class.spec]p9b3: 3298 // 3299 // -- The argument list of the specialization shall not be identical 3300 // to the implicit argument list of the primary template. 3301 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) 3302 << (TUK == TUK_Definition) 3303 << CodeModificationHint::CreateRemoval(SourceRange(LAngleLoc, 3304 RAngleLoc)); 3305 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, 3306 ClassTemplate->getIdentifier(), 3307 TemplateNameLoc, 3308 Attr, 3309 TemplateParams, 3310 AS_none); 3311 } 3312 3313 // FIXME: Diagnose friend partial specializations 3314 3315 // FIXME: Template parameter list matters, too 3316 ClassTemplatePartialSpecializationDecl::Profile(ID, 3317 Converted.getFlatArguments(), 3318 Converted.flatSize(), 3319 Context); 3320 } else 3321 ClassTemplateSpecializationDecl::Profile(ID, 3322 Converted.getFlatArguments(), 3323 Converted.flatSize(), 3324 Context); 3325 void *InsertPos = 0; 3326 ClassTemplateSpecializationDecl *PrevDecl = 0; 3327 3328 if (isPartialSpecialization) 3329 PrevDecl 3330 = ClassTemplate->getPartialSpecializations().FindNodeOrInsertPos(ID, 3331 InsertPos); 3332 else 3333 PrevDecl 3334 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 3335 3336 ClassTemplateSpecializationDecl *Specialization = 0; 3337 3338 // Check whether we can declare a class template specialization in 3339 // the current scope. 3340 if (TUK != TUK_Friend && 3341 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, 3342 TemplateNameLoc, 3343 isPartialSpecialization)) 3344 return true; 3345 3346 // The canonical type 3347 QualType CanonType; 3348 if (PrevDecl && 3349 (PrevDecl->getSpecializationKind() == TSK_Undeclared || 3350 TUK == TUK_Friend)) { 3351 // Since the only prior class template specialization with these 3352 // arguments was referenced but not declared, or we're only 3353 // referencing this specialization as a friend, reuse that 3354 // declaration node as our own, updating its source location to 3355 // reflect our new declaration. 3356 Specialization = PrevDecl; 3357 Specialization->setLocation(TemplateNameLoc); 3358 PrevDecl = 0; 3359 CanonType = Context.getTypeDeclType(Specialization); 3360 } else if (isPartialSpecialization) { 3361 // Build the canonical type that describes the converted template 3362 // arguments of the class template partial specialization. 3363 CanonType = Context.getTemplateSpecializationType( 3364 TemplateName(ClassTemplate), 3365 Converted.getFlatArguments(), 3366 Converted.flatSize()); 3367 3368 // Create a new class template partial specialization declaration node. 3369 ClassTemplatePartialSpecializationDecl *PrevPartial 3370 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); 3371 ClassTemplatePartialSpecializationDecl *Partial 3372 = ClassTemplatePartialSpecializationDecl::Create(Context, 3373 ClassTemplate->getDeclContext(), 3374 TemplateNameLoc, 3375 TemplateParams, 3376 ClassTemplate, 3377 Converted, 3378 TemplateArgs, 3379 PrevPartial); 3380 3381 if (PrevPartial) { 3382 ClassTemplate->getPartialSpecializations().RemoveNode(PrevPartial); 3383 ClassTemplate->getPartialSpecializations().GetOrInsertNode(Partial); 3384 } else { 3385 ClassTemplate->getPartialSpecializations().InsertNode(Partial, InsertPos); 3386 } 3387 Specialization = Partial; 3388 3389 // If we are providing an explicit specialization of a member class 3390 // template specialization, make a note of that. 3391 if (PrevPartial && PrevPartial->getInstantiatedFromMember()) 3392 PrevPartial->setMemberSpecialization(); 3393 3394 // Check that all of the template parameters of the class template 3395 // partial specialization are deducible from the template 3396 // arguments. If not, this class template partial specialization 3397 // will never be used. 3398 llvm::SmallVector<bool, 8> DeducibleParams; 3399 DeducibleParams.resize(TemplateParams->size()); 3400 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true, 3401 TemplateParams->getDepth(), 3402 DeducibleParams); 3403 unsigned NumNonDeducible = 0; 3404 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) 3405 if (!DeducibleParams[I]) 3406 ++NumNonDeducible; 3407 3408 if (NumNonDeducible) { 3409 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible) 3410 << (NumNonDeducible > 1) 3411 << SourceRange(TemplateNameLoc, RAngleLoc); 3412 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) { 3413 if (!DeducibleParams[I]) { 3414 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I)); 3415 if (Param->getDeclName()) 3416 Diag(Param->getLocation(), 3417 diag::note_partial_spec_unused_parameter) 3418 << Param->getDeclName(); 3419 else 3420 Diag(Param->getLocation(), 3421 diag::note_partial_spec_unused_parameter) 3422 << std::string("<anonymous>"); 3423 } 3424 } 3425 } 3426 } else { 3427 // Create a new class template specialization declaration node for 3428 // this explicit specialization or friend declaration. 3429 Specialization 3430 = ClassTemplateSpecializationDecl::Create(Context, 3431 ClassTemplate->getDeclContext(), 3432 TemplateNameLoc, 3433 ClassTemplate, 3434 Converted, 3435 PrevDecl); 3436 3437 if (PrevDecl) { 3438 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 3439 ClassTemplate->getSpecializations().GetOrInsertNode(Specialization); 3440 } else { 3441 ClassTemplate->getSpecializations().InsertNode(Specialization, 3442 InsertPos); 3443 } 3444 3445 CanonType = Context.getTypeDeclType(Specialization); 3446 } 3447 3448 // C++ [temp.expl.spec]p6: 3449 // If a template, a member template or the member of a class template is 3450 // explicitly specialized then that specialization shall be declared 3451 // before the first use of that specialization that would cause an implicit 3452 // instantiation to take place, in every translation unit in which such a 3453 // use occurs; no diagnostic is required. 3454 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { 3455 SourceRange Range(TemplateNameLoc, RAngleLoc); 3456 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) 3457 << Context.getTypeDeclType(Specialization) << Range; 3458 3459 Diag(PrevDecl->getPointOfInstantiation(), 3460 diag::note_instantiation_required_here) 3461 << (PrevDecl->getTemplateSpecializationKind() 3462 != TSK_ImplicitInstantiation); 3463 return true; 3464 } 3465 3466 // If this is not a friend, note that this is an explicit specialization. 3467 if (TUK != TUK_Friend) 3468 Specialization->setSpecializationKind(TSK_ExplicitSpecialization); 3469 3470 // Check that this isn't a redefinition of this specialization. 3471 if (TUK == TUK_Definition) { 3472 if (RecordDecl *Def = Specialization->getDefinition(Context)) { 3473 SourceRange Range(TemplateNameLoc, RAngleLoc); 3474 Diag(TemplateNameLoc, diag::err_redefinition) 3475 << Context.getTypeDeclType(Specialization) << Range; 3476 Diag(Def->getLocation(), diag::note_previous_definition); 3477 Specialization->setInvalidDecl(); 3478 return true; 3479 } 3480 } 3481 3482 // Build the fully-sugared type for this class template 3483 // specialization as the user wrote in the specialization 3484 // itself. This means that we'll pretty-print the type retrieved 3485 // from the specialization's declaration the way that the user 3486 // actually wrote the specialization, rather than formatting the 3487 // name based on the "canonical" representation used to store the 3488 // template arguments in the specialization. 3489 QualType WrittenTy 3490 = Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); 3491 if (TUK != TUK_Friend) 3492 Specialization->setTypeAsWritten(WrittenTy); 3493 TemplateArgsIn.release(); 3494 3495 // C++ [temp.expl.spec]p9: 3496 // A template explicit specialization is in the scope of the 3497 // namespace in which the template was defined. 3498 // 3499 // We actually implement this paragraph where we set the semantic 3500 // context (in the creation of the ClassTemplateSpecializationDecl), 3501 // but we also maintain the lexical context where the actual 3502 // definition occurs. 3503 Specialization->setLexicalDeclContext(CurContext); 3504 3505 // We may be starting the definition of this specialization. 3506 if (TUK == TUK_Definition) 3507 Specialization->startDefinition(); 3508 3509 if (TUK == TUK_Friend) { 3510 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 3511 TemplateNameLoc, 3512 WrittenTy.getTypePtr(), 3513 /*FIXME:*/KWLoc); 3514 Friend->setAccess(AS_public); 3515 CurContext->addDecl(Friend); 3516 } else { 3517 // Add the specialization into its lexical context, so that it can 3518 // be seen when iterating through the list of declarations in that 3519 // context. However, specializations are not found by name lookup. 3520 CurContext->addDecl(Specialization); 3521 } 3522 return DeclPtrTy::make(Specialization); 3523} 3524 3525Sema::DeclPtrTy 3526Sema::ActOnTemplateDeclarator(Scope *S, 3527 MultiTemplateParamsArg TemplateParameterLists, 3528 Declarator &D) { 3529 return HandleDeclarator(S, D, move(TemplateParameterLists), false); 3530} 3531 3532Sema::DeclPtrTy 3533Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, 3534 MultiTemplateParamsArg TemplateParameterLists, 3535 Declarator &D) { 3536 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3537 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3538 "Not a function declarator!"); 3539 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3540 3541 if (FTI.hasPrototype) { 3542 // FIXME: Diagnose arguments without names in C. 3543 } 3544 3545 Scope *ParentScope = FnBodyScope->getParent(); 3546 3547 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3548 move(TemplateParameterLists), 3549 /*IsFunctionDefinition=*/true); 3550 if (FunctionTemplateDecl *FunctionTemplate 3551 = dyn_cast_or_null<FunctionTemplateDecl>(DP.getAs<Decl>())) 3552 return ActOnStartOfFunctionDef(FnBodyScope, 3553 DeclPtrTy::make(FunctionTemplate->getTemplatedDecl())); 3554 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP.getAs<Decl>())) 3555 return ActOnStartOfFunctionDef(FnBodyScope, DeclPtrTy::make(Function)); 3556 return DeclPtrTy(); 3557} 3558 3559/// \brief Diagnose cases where we have an explicit template specialization 3560/// before/after an explicit template instantiation, producing diagnostics 3561/// for those cases where they are required and determining whether the 3562/// new specialization/instantiation will have any effect. 3563/// 3564/// \param NewLoc the location of the new explicit specialization or 3565/// instantiation. 3566/// 3567/// \param NewTSK the kind of the new explicit specialization or instantiation. 3568/// 3569/// \param PrevDecl the previous declaration of the entity. 3570/// 3571/// \param PrevTSK the kind of the old explicit specialization or instantiatin. 3572/// 3573/// \param PrevPointOfInstantiation if valid, indicates where the previus 3574/// declaration was instantiated (either implicitly or explicitly). 3575/// 3576/// \param SuppressNew will be set to true to indicate that the new 3577/// specialization or instantiation has no effect and should be ignored. 3578/// 3579/// \returns true if there was an error that should prevent the introduction of 3580/// the new declaration into the AST, false otherwise. 3581bool 3582Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, 3583 TemplateSpecializationKind NewTSK, 3584 NamedDecl *PrevDecl, 3585 TemplateSpecializationKind PrevTSK, 3586 SourceLocation PrevPointOfInstantiation, 3587 bool &SuppressNew) { 3588 SuppressNew = false; 3589 3590 switch (NewTSK) { 3591 case TSK_Undeclared: 3592 case TSK_ImplicitInstantiation: 3593 assert(false && "Don't check implicit instantiations here"); 3594 return false; 3595 3596 case TSK_ExplicitSpecialization: 3597 switch (PrevTSK) { 3598 case TSK_Undeclared: 3599 case TSK_ExplicitSpecialization: 3600 // Okay, we're just specializing something that is either already 3601 // explicitly specialized or has merely been mentioned without any 3602 // instantiation. 3603 return false; 3604 3605 case TSK_ImplicitInstantiation: 3606 if (PrevPointOfInstantiation.isInvalid()) { 3607 // The declaration itself has not actually been instantiated, so it is 3608 // still okay to specialize it. 3609 return false; 3610 } 3611 // Fall through 3612 3613 case TSK_ExplicitInstantiationDeclaration: 3614 case TSK_ExplicitInstantiationDefinition: 3615 assert((PrevTSK == TSK_ImplicitInstantiation || 3616 PrevPointOfInstantiation.isValid()) && 3617 "Explicit instantiation without point of instantiation?"); 3618 3619 // C++ [temp.expl.spec]p6: 3620 // If a template, a member template or the member of a class template 3621 // is explicitly specialized then that specialization shall be declared 3622 // before the first use of that specialization that would cause an 3623 // implicit instantiation to take place, in every translation unit in 3624 // which such a use occurs; no diagnostic is required. 3625 Diag(NewLoc, diag::err_specialization_after_instantiation) 3626 << PrevDecl; 3627 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) 3628 << (PrevTSK != TSK_ImplicitInstantiation); 3629 3630 return true; 3631 } 3632 break; 3633 3634 case TSK_ExplicitInstantiationDeclaration: 3635 switch (PrevTSK) { 3636 case TSK_ExplicitInstantiationDeclaration: 3637 // This explicit instantiation declaration is redundant (that's okay). 3638 SuppressNew = true; 3639 return false; 3640 3641 case TSK_Undeclared: 3642 case TSK_ImplicitInstantiation: 3643 // We're explicitly instantiating something that may have already been 3644 // implicitly instantiated; that's fine. 3645 return false; 3646 3647 case TSK_ExplicitSpecialization: 3648 // C++0x [temp.explicit]p4: 3649 // For a given set of template parameters, if an explicit instantiation 3650 // of a template appears after a declaration of an explicit 3651 // specialization for that template, the explicit instantiation has no 3652 // effect. 3653 return false; 3654 3655 case TSK_ExplicitInstantiationDefinition: 3656 // C++0x [temp.explicit]p10: 3657 // If an entity is the subject of both an explicit instantiation 3658 // declaration and an explicit instantiation definition in the same 3659 // translation unit, the definition shall follow the declaration. 3660 Diag(NewLoc, 3661 diag::err_explicit_instantiation_declaration_after_definition); 3662 Diag(PrevPointOfInstantiation, 3663 diag::note_explicit_instantiation_definition_here); 3664 assert(PrevPointOfInstantiation.isValid() && 3665 "Explicit instantiation without point of instantiation?"); 3666 SuppressNew = true; 3667 return false; 3668 } 3669 break; 3670 3671 case TSK_ExplicitInstantiationDefinition: 3672 switch (PrevTSK) { 3673 case TSK_Undeclared: 3674 case TSK_ImplicitInstantiation: 3675 // We're explicitly instantiating something that may have already been 3676 // implicitly instantiated; that's fine. 3677 return false; 3678 3679 case TSK_ExplicitSpecialization: 3680 // C++ DR 259, C++0x [temp.explicit]p4: 3681 // For a given set of template parameters, if an explicit 3682 // instantiation of a template appears after a declaration of 3683 // an explicit specialization for that template, the explicit 3684 // instantiation has no effect. 3685 // 3686 // In C++98/03 mode, we only give an extension warning here, because it 3687 // is not not harmful to try to explicitly instantiate something that 3688 // has been explicitly specialized. 3689 if (!getLangOptions().CPlusPlus0x) { 3690 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization) 3691 << PrevDecl; 3692 Diag(PrevDecl->getLocation(), 3693 diag::note_previous_template_specialization); 3694 } 3695 SuppressNew = true; 3696 return false; 3697 3698 case TSK_ExplicitInstantiationDeclaration: 3699 // We're explicity instantiating a definition for something for which we 3700 // were previously asked to suppress instantiations. That's fine. 3701 return false; 3702 3703 case TSK_ExplicitInstantiationDefinition: 3704 // C++0x [temp.spec]p5: 3705 // For a given template and a given set of template-arguments, 3706 // - an explicit instantiation definition shall appear at most once 3707 // in a program, 3708 Diag(NewLoc, diag::err_explicit_instantiation_duplicate) 3709 << PrevDecl; 3710 Diag(PrevPointOfInstantiation, 3711 diag::note_previous_explicit_instantiation); 3712 SuppressNew = true; 3713 return false; 3714 } 3715 break; 3716 } 3717 3718 assert(false && "Missing specialization/instantiation case?"); 3719 3720 return false; 3721} 3722 3723/// \brief Perform semantic analysis for the given function template 3724/// specialization. 3725/// 3726/// This routine performs all of the semantic analysis required for an 3727/// explicit function template specialization. On successful completion, 3728/// the function declaration \p FD will become a function template 3729/// specialization. 3730/// 3731/// \param FD the function declaration, which will be updated to become a 3732/// function template specialization. 3733/// 3734/// \param HasExplicitTemplateArgs whether any template arguments were 3735/// explicitly provided. 3736/// 3737/// \param LAngleLoc the location of the left angle bracket ('<'), if 3738/// template arguments were explicitly provided. 3739/// 3740/// \param ExplicitTemplateArgs the explicitly-provided template arguments, 3741/// if any. 3742/// 3743/// \param NumExplicitTemplateArgs the number of explicitly-provided template 3744/// arguments. This number may be zero even when HasExplicitTemplateArgs is 3745/// true as in, e.g., \c void sort<>(char*, char*); 3746/// 3747/// \param RAngleLoc the location of the right angle bracket ('>'), if 3748/// template arguments were explicitly provided. 3749/// 3750/// \param PrevDecl the set of declarations that 3751bool 3752Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, 3753 const TemplateArgumentListInfo *ExplicitTemplateArgs, 3754 LookupResult &Previous) { 3755 // The set of function template specializations that could match this 3756 // explicit function template specialization. 3757 typedef llvm::SmallVector<FunctionDecl *, 8> CandidateSet; 3758 CandidateSet Candidates; 3759 3760 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 3761 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 3762 I != E; ++I) { 3763 NamedDecl *Ovl = (*I)->getUnderlyingDecl(); 3764 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { 3765 // Only consider templates found within the same semantic lookup scope as 3766 // FD. 3767 if (!FDLookupContext->Equals(Ovl->getDeclContext()->getLookupContext())) 3768 continue; 3769 3770 // C++ [temp.expl.spec]p11: 3771 // A trailing template-argument can be left unspecified in the 3772 // template-id naming an explicit function template specialization 3773 // provided it can be deduced from the function argument type. 3774 // Perform template argument deduction to determine whether we may be 3775 // specializing this template. 3776 // FIXME: It is somewhat wasteful to build 3777 TemplateDeductionInfo Info(Context); 3778 FunctionDecl *Specialization = 0; 3779 if (TemplateDeductionResult TDK 3780 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, 3781 FD->getType(), 3782 Specialization, 3783 Info)) { 3784 // FIXME: Template argument deduction failed; record why it failed, so 3785 // that we can provide nifty diagnostics. 3786 (void)TDK; 3787 continue; 3788 } 3789 3790 // Record this candidate. 3791 Candidates.push_back(Specialization); 3792 } 3793 } 3794 3795 // Find the most specialized function template. 3796 FunctionDecl *Specialization = getMostSpecialized(Candidates.data(), 3797 Candidates.size(), 3798 TPOC_Other, 3799 FD->getLocation(), 3800 PartialDiagnostic(diag::err_function_template_spec_no_match) 3801 << FD->getDeclName(), 3802 PartialDiagnostic(diag::err_function_template_spec_ambiguous) 3803 << FD->getDeclName() << (ExplicitTemplateArgs != 0), 3804 PartialDiagnostic(diag::note_function_template_spec_matched)); 3805 if (!Specialization) 3806 return true; 3807 3808 // FIXME: Check if the prior specialization has a point of instantiation. 3809 // If so, we have run afoul of . 3810 3811 // Check the scope of this explicit specialization. 3812 if (CheckTemplateSpecializationScope(*this, 3813 Specialization->getPrimaryTemplate(), 3814 Specialization, FD->getLocation(), 3815 false)) 3816 return true; 3817 3818 // C++ [temp.expl.spec]p6: 3819 // If a template, a member template or the member of a class template is 3820 // explicitly specialized then that specialization shall be declared 3821 // before the first use of that specialization that would cause an implicit 3822 // instantiation to take place, in every translation unit in which such a 3823 // use occurs; no diagnostic is required. 3824 FunctionTemplateSpecializationInfo *SpecInfo 3825 = Specialization->getTemplateSpecializationInfo(); 3826 assert(SpecInfo && "Function template specialization info missing?"); 3827 if (SpecInfo->getPointOfInstantiation().isValid()) { 3828 Diag(FD->getLocation(), diag::err_specialization_after_instantiation) 3829 << FD; 3830 Diag(SpecInfo->getPointOfInstantiation(), 3831 diag::note_instantiation_required_here) 3832 << (Specialization->getTemplateSpecializationKind() 3833 != TSK_ImplicitInstantiation); 3834 return true; 3835 } 3836 3837 // Mark the prior declaration as an explicit specialization, so that later 3838 // clients know that this is an explicit specialization. 3839 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); 3840 3841 // Turn the given function declaration into a function template 3842 // specialization, with the template arguments from the previous 3843 // specialization. 3844 FD->setFunctionTemplateSpecialization(Context, 3845 Specialization->getPrimaryTemplate(), 3846 new (Context) TemplateArgumentList( 3847 *Specialization->getTemplateSpecializationArgs()), 3848 /*InsertPos=*/0, 3849 TSK_ExplicitSpecialization); 3850 3851 // The "previous declaration" for this function template specialization is 3852 // the prior function template specialization. 3853 Previous.clear(); 3854 Previous.addDecl(Specialization); 3855 return false; 3856} 3857 3858/// \brief Perform semantic analysis for the given non-template member 3859/// specialization. 3860/// 3861/// This routine performs all of the semantic analysis required for an 3862/// explicit member function specialization. On successful completion, 3863/// the function declaration \p FD will become a member function 3864/// specialization. 3865/// 3866/// \param Member the member declaration, which will be updated to become a 3867/// specialization. 3868/// 3869/// \param Previous the set of declarations, one of which may be specialized 3870/// by this function specialization; the set will be modified to contain the 3871/// redeclared member. 3872bool 3873Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { 3874 assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); 3875 3876 // Try to find the member we are instantiating. 3877 NamedDecl *Instantiation = 0; 3878 NamedDecl *InstantiatedFrom = 0; 3879 MemberSpecializationInfo *MSInfo = 0; 3880 3881 if (Previous.empty()) { 3882 // Nowhere to look anyway. 3883 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { 3884 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 3885 I != E; ++I) { 3886 NamedDecl *D = (*I)->getUnderlyingDecl(); 3887 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 3888 if (Context.hasSameType(Function->getType(), Method->getType())) { 3889 Instantiation = Method; 3890 InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); 3891 MSInfo = Method->getMemberSpecializationInfo(); 3892 break; 3893 } 3894 } 3895 } 3896 } else if (isa<VarDecl>(Member)) { 3897 VarDecl *PrevVar; 3898 if (Previous.isSingleResult() && 3899 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) 3900 if (PrevVar->isStaticDataMember()) { 3901 Instantiation = PrevVar; 3902 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); 3903 MSInfo = PrevVar->getMemberSpecializationInfo(); 3904 } 3905 } else if (isa<RecordDecl>(Member)) { 3906 CXXRecordDecl *PrevRecord; 3907 if (Previous.isSingleResult() && 3908 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { 3909 Instantiation = PrevRecord; 3910 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); 3911 MSInfo = PrevRecord->getMemberSpecializationInfo(); 3912 } 3913 } 3914 3915 if (!Instantiation) { 3916 // There is no previous declaration that matches. Since member 3917 // specializations are always out-of-line, the caller will complain about 3918 // this mismatch later. 3919 return false; 3920 } 3921 3922 // Make sure that this is a specialization of a member. 3923 if (!InstantiatedFrom) { 3924 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) 3925 << Member; 3926 Diag(Instantiation->getLocation(), diag::note_specialized_decl); 3927 return true; 3928 } 3929 3930 // C++ [temp.expl.spec]p6: 3931 // If a template, a member template or the member of a class template is 3932 // explicitly specialized then that spe- cialization shall be declared 3933 // before the first use of that specialization that would cause an implicit 3934 // instantiation to take place, in every translation unit in which such a 3935 // use occurs; no diagnostic is required. 3936 assert(MSInfo && "Member specialization info missing?"); 3937 if (MSInfo->getPointOfInstantiation().isValid()) { 3938 Diag(Member->getLocation(), diag::err_specialization_after_instantiation) 3939 << Member; 3940 Diag(MSInfo->getPointOfInstantiation(), 3941 diag::note_instantiation_required_here) 3942 << (MSInfo->getTemplateSpecializationKind() != TSK_ImplicitInstantiation); 3943 return true; 3944 } 3945 3946 // Check the scope of this explicit specialization. 3947 if (CheckTemplateSpecializationScope(*this, 3948 InstantiatedFrom, 3949 Instantiation, Member->getLocation(), 3950 false)) 3951 return true; 3952 3953 // Note that this is an explicit instantiation of a member. 3954 // the original declaration to note that it is an explicit specialization 3955 // (if it was previously an implicit instantiation). This latter step 3956 // makes bookkeeping easier. 3957 if (isa<FunctionDecl>(Member)) { 3958 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); 3959 if (InstantiationFunction->getTemplateSpecializationKind() == 3960 TSK_ImplicitInstantiation) { 3961 InstantiationFunction->setTemplateSpecializationKind( 3962 TSK_ExplicitSpecialization); 3963 InstantiationFunction->setLocation(Member->getLocation()); 3964 } 3965 3966 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( 3967 cast<CXXMethodDecl>(InstantiatedFrom), 3968 TSK_ExplicitSpecialization); 3969 } else if (isa<VarDecl>(Member)) { 3970 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); 3971 if (InstantiationVar->getTemplateSpecializationKind() == 3972 TSK_ImplicitInstantiation) { 3973 InstantiationVar->setTemplateSpecializationKind( 3974 TSK_ExplicitSpecialization); 3975 InstantiationVar->setLocation(Member->getLocation()); 3976 } 3977 3978 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), 3979 cast<VarDecl>(InstantiatedFrom), 3980 TSK_ExplicitSpecialization); 3981 } else { 3982 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain"); 3983 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); 3984 if (InstantiationClass->getTemplateSpecializationKind() == 3985 TSK_ImplicitInstantiation) { 3986 InstantiationClass->setTemplateSpecializationKind( 3987 TSK_ExplicitSpecialization); 3988 InstantiationClass->setLocation(Member->getLocation()); 3989 } 3990 3991 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 3992 cast<CXXRecordDecl>(InstantiatedFrom), 3993 TSK_ExplicitSpecialization); 3994 } 3995 3996 // Save the caller the trouble of having to figure out which declaration 3997 // this specialization matches. 3998 Previous.clear(); 3999 Previous.addDecl(Instantiation); 4000 return false; 4001} 4002 4003/// \brief Check the scope of an explicit instantiation. 4004static void CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, 4005 SourceLocation InstLoc, 4006 bool WasQualifiedName) { 4007 DeclContext *ExpectedContext 4008 = D->getDeclContext()->getEnclosingNamespaceContext()->getLookupContext(); 4009 DeclContext *CurContext = S.CurContext->getLookupContext(); 4010 4011 // C++0x [temp.explicit]p2: 4012 // An explicit instantiation shall appear in an enclosing namespace of its 4013 // template. 4014 // 4015 // This is DR275, which we do not retroactively apply to C++98/03. 4016 if (S.getLangOptions().CPlusPlus0x && 4017 !CurContext->Encloses(ExpectedContext)) { 4018 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(ExpectedContext)) 4019 S.Diag(InstLoc, diag::err_explicit_instantiation_out_of_scope) 4020 << D << NS; 4021 else 4022 S.Diag(InstLoc, diag::err_explicit_instantiation_must_be_global) 4023 << D; 4024 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4025 return; 4026 } 4027 4028 // C++0x [temp.explicit]p2: 4029 // If the name declared in the explicit instantiation is an unqualified 4030 // name, the explicit instantiation shall appear in the namespace where 4031 // its template is declared or, if that namespace is inline (7.3.1), any 4032 // namespace from its enclosing namespace set. 4033 if (WasQualifiedName) 4034 return; 4035 4036 if (CurContext->Equals(ExpectedContext)) 4037 return; 4038 4039 S.Diag(InstLoc, diag::err_explicit_instantiation_unqualified_wrong_namespace) 4040 << D << ExpectedContext; 4041 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4042} 4043 4044/// \brief Determine whether the given scope specifier has a template-id in it. 4045static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { 4046 if (!SS.isSet()) 4047 return false; 4048 4049 // C++0x [temp.explicit]p2: 4050 // If the explicit instantiation is for a member function, a member class 4051 // or a static data member of a class template specialization, the name of 4052 // the class template specialization in the qualified-id for the member 4053 // name shall be a simple-template-id. 4054 // 4055 // C++98 has the same restriction, just worded differently. 4056 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 4057 NNS; NNS = NNS->getPrefix()) 4058 if (Type *T = NNS->getAsType()) 4059 if (isa<TemplateSpecializationType>(T)) 4060 return true; 4061 4062 return false; 4063} 4064 4065// Explicit instantiation of a class template specialization 4066// FIXME: Implement extern template semantics 4067Sema::DeclResult 4068Sema::ActOnExplicitInstantiation(Scope *S, 4069 SourceLocation ExternLoc, 4070 SourceLocation TemplateLoc, 4071 unsigned TagSpec, 4072 SourceLocation KWLoc, 4073 const CXXScopeSpec &SS, 4074 TemplateTy TemplateD, 4075 SourceLocation TemplateNameLoc, 4076 SourceLocation LAngleLoc, 4077 ASTTemplateArgsPtr TemplateArgsIn, 4078 SourceLocation RAngleLoc, 4079 AttributeList *Attr) { 4080 // Find the class template we're specializing 4081 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 4082 ClassTemplateDecl *ClassTemplate 4083 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); 4084 4085 // Check that the specialization uses the same tag kind as the 4086 // original template. 4087 TagDecl::TagKind Kind; 4088 switch (TagSpec) { 4089 default: assert(0 && "Unknown tag type!"); 4090 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 4091 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 4092 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 4093 } 4094 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 4095 Kind, KWLoc, 4096 *ClassTemplate->getIdentifier())) { 4097 Diag(KWLoc, diag::err_use_with_wrong_tag) 4098 << ClassTemplate 4099 << CodeModificationHint::CreateReplacement(KWLoc, 4100 ClassTemplate->getTemplatedDecl()->getKindName()); 4101 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 4102 diag::note_previous_use); 4103 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 4104 } 4105 4106 // C++0x [temp.explicit]p2: 4107 // There are two forms of explicit instantiation: an explicit instantiation 4108 // definition and an explicit instantiation declaration. An explicit 4109 // instantiation declaration begins with the extern keyword. [...] 4110 TemplateSpecializationKind TSK 4111 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4112 : TSK_ExplicitInstantiationDeclaration; 4113 4114 // Translate the parser's template argument list in our AST format. 4115 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 4116 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 4117 4118 // Check that the template argument list is well-formed for this 4119 // template. 4120 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 4121 TemplateArgs.size()); 4122 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 4123 TemplateArgs, false, Converted)) 4124 return true; 4125 4126 assert((Converted.structuredSize() == 4127 ClassTemplate->getTemplateParameters()->size()) && 4128 "Converted template argument list is too short!"); 4129 4130 // Find the class template specialization declaration that 4131 // corresponds to these arguments. 4132 llvm::FoldingSetNodeID ID; 4133 ClassTemplateSpecializationDecl::Profile(ID, 4134 Converted.getFlatArguments(), 4135 Converted.flatSize(), 4136 Context); 4137 void *InsertPos = 0; 4138 ClassTemplateSpecializationDecl *PrevDecl 4139 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 4140 4141 // C++0x [temp.explicit]p2: 4142 // [...] An explicit instantiation shall appear in an enclosing 4143 // namespace of its template. [...] 4144 // 4145 // This is C++ DR 275. 4146 CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, 4147 SS.isSet()); 4148 4149 ClassTemplateSpecializationDecl *Specialization = 0; 4150 4151 bool ReusedDecl = false; 4152 if (PrevDecl) { 4153 bool SuppressNew = false; 4154 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, 4155 PrevDecl, 4156 PrevDecl->getSpecializationKind(), 4157 PrevDecl->getPointOfInstantiation(), 4158 SuppressNew)) 4159 return DeclPtrTy::make(PrevDecl); 4160 4161 if (SuppressNew) 4162 return DeclPtrTy::make(PrevDecl); 4163 4164 if (PrevDecl->getSpecializationKind() == TSK_ImplicitInstantiation || 4165 PrevDecl->getSpecializationKind() == TSK_Undeclared) { 4166 // Since the only prior class template specialization with these 4167 // arguments was referenced but not declared, reuse that 4168 // declaration node as our own, updating its source location to 4169 // reflect our new declaration. 4170 Specialization = PrevDecl; 4171 Specialization->setLocation(TemplateNameLoc); 4172 PrevDecl = 0; 4173 ReusedDecl = true; 4174 } 4175 } 4176 4177 if (!Specialization) { 4178 // Create a new class template specialization declaration node for 4179 // this explicit specialization. 4180 Specialization 4181 = ClassTemplateSpecializationDecl::Create(Context, 4182 ClassTemplate->getDeclContext(), 4183 TemplateNameLoc, 4184 ClassTemplate, 4185 Converted, PrevDecl); 4186 4187 if (PrevDecl) { 4188 // Remove the previous declaration from the folding set, since we want 4189 // to introduce a new declaration. 4190 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 4191 ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 4192 } 4193 4194 // Insert the new specialization. 4195 ClassTemplate->getSpecializations().InsertNode(Specialization, InsertPos); 4196 } 4197 4198 // Build the fully-sugared type for this explicit instantiation as 4199 // the user wrote in the explicit instantiation itself. This means 4200 // that we'll pretty-print the type retrieved from the 4201 // specialization's declaration the way that the user actually wrote 4202 // the explicit instantiation, rather than formatting the name based 4203 // on the "canonical" representation used to store the template 4204 // arguments in the specialization. 4205 QualType WrittenTy 4206 = Context.getTemplateSpecializationType(Name, TemplateArgs, 4207 Context.getTypeDeclType(Specialization)); 4208 Specialization->setTypeAsWritten(WrittenTy); 4209 TemplateArgsIn.release(); 4210 4211 if (!ReusedDecl) { 4212 // Add the explicit instantiation into its lexical context. However, 4213 // since explicit instantiations are never found by name lookup, we 4214 // just put it into the declaration context directly. 4215 Specialization->setLexicalDeclContext(CurContext); 4216 CurContext->addDecl(Specialization); 4217 } 4218 4219 // C++ [temp.explicit]p3: 4220 // A definition of a class template or class member template 4221 // shall be in scope at the point of the explicit instantiation of 4222 // the class template or class member template. 4223 // 4224 // This check comes when we actually try to perform the 4225 // instantiation. 4226 ClassTemplateSpecializationDecl *Def 4227 = cast_or_null<ClassTemplateSpecializationDecl>( 4228 Specialization->getDefinition(Context)); 4229 if (!Def) 4230 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); 4231 4232 // Instantiate the members of this class template specialization. 4233 Def = cast_or_null<ClassTemplateSpecializationDecl>( 4234 Specialization->getDefinition(Context)); 4235 if (Def) 4236 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); 4237 4238 return DeclPtrTy::make(Specialization); 4239} 4240 4241// Explicit instantiation of a member class of a class template. 4242Sema::DeclResult 4243Sema::ActOnExplicitInstantiation(Scope *S, 4244 SourceLocation ExternLoc, 4245 SourceLocation TemplateLoc, 4246 unsigned TagSpec, 4247 SourceLocation KWLoc, 4248 const CXXScopeSpec &SS, 4249 IdentifierInfo *Name, 4250 SourceLocation NameLoc, 4251 AttributeList *Attr) { 4252 4253 bool Owned = false; 4254 bool IsDependent = false; 4255 DeclPtrTy TagD = ActOnTag(S, TagSpec, Action::TUK_Reference, 4256 KWLoc, SS, Name, NameLoc, Attr, AS_none, 4257 MultiTemplateParamsArg(*this, 0, 0), 4258 Owned, IsDependent); 4259 assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); 4260 4261 if (!TagD) 4262 return true; 4263 4264 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4265 if (Tag->isEnum()) { 4266 Diag(TemplateLoc, diag::err_explicit_instantiation_enum) 4267 << Context.getTypeDeclType(Tag); 4268 return true; 4269 } 4270 4271 if (Tag->isInvalidDecl()) 4272 return true; 4273 4274 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); 4275 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); 4276 if (!Pattern) { 4277 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) 4278 << Context.getTypeDeclType(Record); 4279 Diag(Record->getLocation(), diag::note_nontemplate_decl_here); 4280 return true; 4281 } 4282 4283 // C++0x [temp.explicit]p2: 4284 // If the explicit instantiation is for a class or member class, the 4285 // elaborated-type-specifier in the declaration shall include a 4286 // simple-template-id. 4287 // 4288 // C++98 has the same restriction, just worded differently. 4289 if (!ScopeSpecifierHasTemplateId(SS)) 4290 Diag(TemplateLoc, diag::err_explicit_instantiation_without_qualified_id) 4291 << Record << SS.getRange(); 4292 4293 // C++0x [temp.explicit]p2: 4294 // There are two forms of explicit instantiation: an explicit instantiation 4295 // definition and an explicit instantiation declaration. An explicit 4296 // instantiation declaration begins with the extern keyword. [...] 4297 TemplateSpecializationKind TSK 4298 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4299 : TSK_ExplicitInstantiationDeclaration; 4300 4301 // C++0x [temp.explicit]p2: 4302 // [...] An explicit instantiation shall appear in an enclosing 4303 // namespace of its template. [...] 4304 // 4305 // This is C++ DR 275. 4306 CheckExplicitInstantiationScope(*this, Record, NameLoc, true); 4307 4308 // Verify that it is okay to explicitly instantiate here. 4309 CXXRecordDecl *PrevDecl 4310 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration()); 4311 if (!PrevDecl && Record->getDefinition(Context)) 4312 PrevDecl = Record; 4313 if (PrevDecl) { 4314 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); 4315 bool SuppressNew = false; 4316 assert(MSInfo && "No member specialization information?"); 4317 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, 4318 PrevDecl, 4319 MSInfo->getTemplateSpecializationKind(), 4320 MSInfo->getPointOfInstantiation(), 4321 SuppressNew)) 4322 return true; 4323 if (SuppressNew) 4324 return TagD; 4325 } 4326 4327 CXXRecordDecl *RecordDef 4328 = cast_or_null<CXXRecordDecl>(Record->getDefinition(Context)); 4329 if (!RecordDef) { 4330 // C++ [temp.explicit]p3: 4331 // A definition of a member class of a class template shall be in scope 4332 // at the point of an explicit instantiation of the member class. 4333 CXXRecordDecl *Def 4334 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition(Context)); 4335 if (!Def) { 4336 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) 4337 << 0 << Record->getDeclName() << Record->getDeclContext(); 4338 Diag(Pattern->getLocation(), diag::note_forward_declaration) 4339 << Pattern; 4340 return true; 4341 } else { 4342 if (InstantiateClass(NameLoc, Record, Def, 4343 getTemplateInstantiationArgs(Record), 4344 TSK)) 4345 return true; 4346 4347 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition(Context)); 4348 if (!RecordDef) 4349 return true; 4350 } 4351 } 4352 4353 // Instantiate all of the members of the class. 4354 InstantiateClassMembers(NameLoc, RecordDef, 4355 getTemplateInstantiationArgs(Record), TSK); 4356 4357 // FIXME: We don't have any representation for explicit instantiations of 4358 // member classes. Such a representation is not needed for compilation, but it 4359 // should be available for clients that want to see all of the declarations in 4360 // the source code. 4361 return TagD; 4362} 4363 4364Sema::DeclResult Sema::ActOnExplicitInstantiation(Scope *S, 4365 SourceLocation ExternLoc, 4366 SourceLocation TemplateLoc, 4367 Declarator &D) { 4368 // Explicit instantiations always require a name. 4369 DeclarationName Name = GetNameForDeclarator(D); 4370 if (!Name) { 4371 if (!D.isInvalidType()) 4372 Diag(D.getDeclSpec().getSourceRange().getBegin(), 4373 diag::err_explicit_instantiation_requires_name) 4374 << D.getDeclSpec().getSourceRange() 4375 << D.getSourceRange(); 4376 4377 return true; 4378 } 4379 4380 // The scope passed in may not be a decl scope. Zip up the scope tree until 4381 // we find one that is. 4382 while ((S->getFlags() & Scope::DeclScope) == 0 || 4383 (S->getFlags() & Scope::TemplateParamScope) != 0) 4384 S = S->getParent(); 4385 4386 // Determine the type of the declaration. 4387 QualType R = GetTypeForDeclarator(D, S, 0); 4388 if (R.isNull()) 4389 return true; 4390 4391 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 4392 // Cannot explicitly instantiate a typedef. 4393 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) 4394 << Name; 4395 return true; 4396 } 4397 4398 // C++0x [temp.explicit]p1: 4399 // [...] An explicit instantiation of a function template shall not use the 4400 // inline or constexpr specifiers. 4401 // Presumably, this also applies to member functions of class templates as 4402 // well. 4403 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x) 4404 Diag(D.getDeclSpec().getInlineSpecLoc(), 4405 diag::err_explicit_instantiation_inline) 4406 <<CodeModificationHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 4407 4408 // FIXME: check for constexpr specifier. 4409 4410 // C++0x [temp.explicit]p2: 4411 // There are two forms of explicit instantiation: an explicit instantiation 4412 // definition and an explicit instantiation declaration. An explicit 4413 // instantiation declaration begins with the extern keyword. [...] 4414 TemplateSpecializationKind TSK 4415 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4416 : TSK_ExplicitInstantiationDeclaration; 4417 4418 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName); 4419 LookupParsedName(Previous, S, &D.getCXXScopeSpec()); 4420 4421 if (!R->isFunctionType()) { 4422 // C++ [temp.explicit]p1: 4423 // A [...] static data member of a class template can be explicitly 4424 // instantiated from the member definition associated with its class 4425 // template. 4426 if (Previous.isAmbiguous()) 4427 return true; 4428 4429 VarDecl *Prev = Previous.getAsSingle<VarDecl>(); 4430 if (!Prev || !Prev->isStaticDataMember()) { 4431 // We expect to see a data data member here. 4432 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) 4433 << Name; 4434 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 4435 P != PEnd; ++P) 4436 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); 4437 return true; 4438 } 4439 4440 if (!Prev->getInstantiatedFromStaticDataMember()) { 4441 // FIXME: Check for explicit specialization? 4442 Diag(D.getIdentifierLoc(), 4443 diag::err_explicit_instantiation_data_member_not_instantiated) 4444 << Prev; 4445 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); 4446 // FIXME: Can we provide a note showing where this was declared? 4447 return true; 4448 } 4449 4450 // C++0x [temp.explicit]p2: 4451 // If the explicit instantiation is for a member function, a member class 4452 // or a static data member of a class template specialization, the name of 4453 // the class template specialization in the qualified-id for the member 4454 // name shall be a simple-template-id. 4455 // 4456 // C++98 has the same restriction, just worded differently. 4457 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 4458 Diag(D.getIdentifierLoc(), 4459 diag::err_explicit_instantiation_without_qualified_id) 4460 << Prev << D.getCXXScopeSpec().getRange(); 4461 4462 // Check the scope of this explicit instantiation. 4463 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); 4464 4465 // Verify that it is okay to explicitly instantiate here. 4466 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); 4467 assert(MSInfo && "Missing static data member specialization info?"); 4468 bool SuppressNew = false; 4469 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, 4470 MSInfo->getTemplateSpecializationKind(), 4471 MSInfo->getPointOfInstantiation(), 4472 SuppressNew)) 4473 return true; 4474 if (SuppressNew) 4475 return DeclPtrTy(); 4476 4477 // Instantiate static data member. 4478 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 4479 if (TSK == TSK_ExplicitInstantiationDefinition) 4480 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev, false, 4481 /*DefinitionRequired=*/true); 4482 4483 // FIXME: Create an ExplicitInstantiation node? 4484 return DeclPtrTy(); 4485 } 4486 4487 // If the declarator is a template-id, translate the parser's template 4488 // argument list into our AST format. 4489 bool HasExplicitTemplateArgs = false; 4490 TemplateArgumentListInfo TemplateArgs; 4491 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4492 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4493 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4494 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4495 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4496 TemplateId->getTemplateArgs(), 4497 TemplateId->NumArgs); 4498 translateTemplateArguments(TemplateArgsPtr, TemplateArgs); 4499 HasExplicitTemplateArgs = true; 4500 TemplateArgsPtr.release(); 4501 } 4502 4503 // C++ [temp.explicit]p1: 4504 // A [...] function [...] can be explicitly instantiated from its template. 4505 // A member function [...] of a class template can be explicitly 4506 // instantiated from the member definition associated with its class 4507 // template. 4508 llvm::SmallVector<FunctionDecl *, 8> Matches; 4509 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 4510 P != PEnd; ++P) { 4511 NamedDecl *Prev = *P; 4512 if (!HasExplicitTemplateArgs) { 4513 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { 4514 if (Context.hasSameUnqualifiedType(Method->getType(), R)) { 4515 Matches.clear(); 4516 Matches.push_back(Method); 4517 break; 4518 } 4519 } 4520 } 4521 4522 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); 4523 if (!FunTmpl) 4524 continue; 4525 4526 TemplateDeductionInfo Info(Context); 4527 FunctionDecl *Specialization = 0; 4528 if (TemplateDeductionResult TDK 4529 = DeduceTemplateArguments(FunTmpl, 4530 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 4531 R, Specialization, Info)) { 4532 // FIXME: Keep track of almost-matches? 4533 (void)TDK; 4534 continue; 4535 } 4536 4537 Matches.push_back(Specialization); 4538 } 4539 4540 // Find the most specialized function template specialization. 4541 FunctionDecl *Specialization 4542 = getMostSpecialized(Matches.data(), Matches.size(), TPOC_Other, 4543 D.getIdentifierLoc(), 4544 PartialDiagnostic(diag::err_explicit_instantiation_not_known) << Name, 4545 PartialDiagnostic(diag::err_explicit_instantiation_ambiguous) << Name, 4546 PartialDiagnostic(diag::note_explicit_instantiation_candidate)); 4547 4548 if (!Specialization) 4549 return true; 4550 4551 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { 4552 Diag(D.getIdentifierLoc(), 4553 diag::err_explicit_instantiation_member_function_not_instantiated) 4554 << Specialization 4555 << (Specialization->getTemplateSpecializationKind() == 4556 TSK_ExplicitSpecialization); 4557 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); 4558 return true; 4559 } 4560 4561 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration(); 4562 if (!PrevDecl && Specialization->isThisDeclarationADefinition()) 4563 PrevDecl = Specialization; 4564 4565 if (PrevDecl) { 4566 bool SuppressNew = false; 4567 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, 4568 PrevDecl, 4569 PrevDecl->getTemplateSpecializationKind(), 4570 PrevDecl->getPointOfInstantiation(), 4571 SuppressNew)) 4572 return true; 4573 4574 // FIXME: We may still want to build some representation of this 4575 // explicit specialization. 4576 if (SuppressNew) 4577 return DeclPtrTy(); 4578 } 4579 4580 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 4581 4582 if (TSK == TSK_ExplicitInstantiationDefinition) 4583 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization, 4584 false, /*DefinitionRequired=*/true); 4585 4586 // C++0x [temp.explicit]p2: 4587 // If the explicit instantiation is for a member function, a member class 4588 // or a static data member of a class template specialization, the name of 4589 // the class template specialization in the qualified-id for the member 4590 // name shall be a simple-template-id. 4591 // 4592 // C++98 has the same restriction, just worded differently. 4593 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); 4594 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && 4595 D.getCXXScopeSpec().isSet() && 4596 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 4597 Diag(D.getIdentifierLoc(), 4598 diag::err_explicit_instantiation_without_qualified_id) 4599 << Specialization << D.getCXXScopeSpec().getRange(); 4600 4601 CheckExplicitInstantiationScope(*this, 4602 FunTmpl? (NamedDecl *)FunTmpl 4603 : Specialization->getInstantiatedFromMemberFunction(), 4604 D.getIdentifierLoc(), 4605 D.getCXXScopeSpec().isSet()); 4606 4607 // FIXME: Create some kind of ExplicitInstantiationDecl here. 4608 return DeclPtrTy(); 4609} 4610 4611Sema::TypeResult 4612Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4613 const CXXScopeSpec &SS, IdentifierInfo *Name, 4614 SourceLocation TagLoc, SourceLocation NameLoc) { 4615 // This has to hold, because SS is expected to be defined. 4616 assert(Name && "Expected a name in a dependent tag"); 4617 4618 NestedNameSpecifier *NNS 4619 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 4620 if (!NNS) 4621 return true; 4622 4623 QualType T = CheckTypenameType(NNS, *Name, SourceRange(TagLoc, NameLoc)); 4624 if (T.isNull()) 4625 return true; 4626 4627 TagDecl::TagKind TagKind = TagDecl::getTagKindForTypeSpec(TagSpec); 4628 QualType ElabType = Context.getElaboratedType(T, TagKind); 4629 4630 return ElabType.getAsOpaquePtr(); 4631} 4632 4633Sema::TypeResult 4634Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS, 4635 const IdentifierInfo &II, SourceLocation IdLoc) { 4636 NestedNameSpecifier *NNS 4637 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 4638 if (!NNS) 4639 return true; 4640 4641 QualType T = CheckTypenameType(NNS, II, SourceRange(TypenameLoc, IdLoc)); 4642 if (T.isNull()) 4643 return true; 4644 return T.getAsOpaquePtr(); 4645} 4646 4647Sema::TypeResult 4648Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS, 4649 SourceLocation TemplateLoc, TypeTy *Ty) { 4650 QualType T = GetTypeFromParser(Ty); 4651 NestedNameSpecifier *NNS 4652 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 4653 const TemplateSpecializationType *TemplateId 4654 = T->getAs<TemplateSpecializationType>(); 4655 assert(TemplateId && "Expected a template specialization type"); 4656 4657 if (computeDeclContext(SS, false)) { 4658 // If we can compute a declaration context, then the "typename" 4659 // keyword was superfluous. Just build a QualifiedNameType to keep 4660 // track of the nested-name-specifier. 4661 4662 // FIXME: Note that the QualifiedNameType had the "typename" keyword! 4663 return Context.getQualifiedNameType(NNS, T).getAsOpaquePtr(); 4664 } 4665 4666 return Context.getTypenameType(NNS, TemplateId).getAsOpaquePtr(); 4667} 4668 4669/// \brief Build the type that describes a C++ typename specifier, 4670/// e.g., "typename T::type". 4671QualType 4672Sema::CheckTypenameType(NestedNameSpecifier *NNS, const IdentifierInfo &II, 4673 SourceRange Range) { 4674 CXXRecordDecl *CurrentInstantiation = 0; 4675 if (NNS->isDependent()) { 4676 CurrentInstantiation = getCurrentInstantiationOf(NNS); 4677 4678 // If the nested-name-specifier does not refer to the current 4679 // instantiation, then build a typename type. 4680 if (!CurrentInstantiation) 4681 return Context.getTypenameType(NNS, &II); 4682 4683 // The nested-name-specifier refers to the current instantiation, so the 4684 // "typename" keyword itself is superfluous. In C++03, the program is 4685 // actually ill-formed. However, DR 382 (in C++0x CD1) allows such 4686 // extraneous "typename" keywords, and we retroactively apply this DR to 4687 // C++03 code. 4688 } 4689 4690 DeclContext *Ctx = 0; 4691 4692 if (CurrentInstantiation) 4693 Ctx = CurrentInstantiation; 4694 else { 4695 CXXScopeSpec SS; 4696 SS.setScopeRep(NNS); 4697 SS.setRange(Range); 4698 if (RequireCompleteDeclContext(SS)) 4699 return QualType(); 4700 4701 Ctx = computeDeclContext(SS); 4702 } 4703 assert(Ctx && "No declaration context?"); 4704 4705 DeclarationName Name(&II); 4706 LookupResult Result(*this, Name, Range.getEnd(), LookupOrdinaryName); 4707 LookupQualifiedName(Result, Ctx); 4708 unsigned DiagID = 0; 4709 Decl *Referenced = 0; 4710 switch (Result.getResultKind()) { 4711 case LookupResult::NotFound: 4712 DiagID = diag::err_typename_nested_not_found; 4713 break; 4714 4715 case LookupResult::Found: 4716 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { 4717 // We found a type. Build a QualifiedNameType, since the 4718 // typename-specifier was just sugar. FIXME: Tell 4719 // QualifiedNameType that it has a "typename" prefix. 4720 return Context.getQualifiedNameType(NNS, Context.getTypeDeclType(Type)); 4721 } 4722 4723 DiagID = diag::err_typename_nested_not_type; 4724 Referenced = Result.getFoundDecl(); 4725 break; 4726 4727 case LookupResult::FoundUnresolvedValue: 4728 llvm_unreachable("unresolved using decl in non-dependent context"); 4729 return QualType(); 4730 4731 case LookupResult::FoundOverloaded: 4732 DiagID = diag::err_typename_nested_not_type; 4733 Referenced = *Result.begin(); 4734 break; 4735 4736 case LookupResult::Ambiguous: 4737 return QualType(); 4738 } 4739 4740 // If we get here, it's because name lookup did not find a 4741 // type. Emit an appropriate diagnostic and return an error. 4742 Diag(Range.getEnd(), DiagID) << Range << Name << Ctx; 4743 if (Referenced) 4744 Diag(Referenced->getLocation(), diag::note_typename_refers_here) 4745 << Name; 4746 return QualType(); 4747} 4748 4749namespace { 4750 // See Sema::RebuildTypeInCurrentInstantiation 4751 class CurrentInstantiationRebuilder 4752 : public TreeTransform<CurrentInstantiationRebuilder> { 4753 SourceLocation Loc; 4754 DeclarationName Entity; 4755 4756 public: 4757 CurrentInstantiationRebuilder(Sema &SemaRef, 4758 SourceLocation Loc, 4759 DeclarationName Entity) 4760 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), 4761 Loc(Loc), Entity(Entity) { } 4762 4763 /// \brief Determine whether the given type \p T has already been 4764 /// transformed. 4765 /// 4766 /// For the purposes of type reconstruction, a type has already been 4767 /// transformed if it is NULL or if it is not dependent. 4768 bool AlreadyTransformed(QualType T) { 4769 return T.isNull() || !T->isDependentType(); 4770 } 4771 4772 /// \brief Returns the location of the entity whose type is being 4773 /// rebuilt. 4774 SourceLocation getBaseLocation() { return Loc; } 4775 4776 /// \brief Returns the name of the entity whose type is being rebuilt. 4777 DeclarationName getBaseEntity() { return Entity; } 4778 4779 /// \brief Sets the "base" location and entity when that 4780 /// information is known based on another transformation. 4781 void setBase(SourceLocation Loc, DeclarationName Entity) { 4782 this->Loc = Loc; 4783 this->Entity = Entity; 4784 } 4785 4786 /// \brief Transforms an expression by returning the expression itself 4787 /// (an identity function). 4788 /// 4789 /// FIXME: This is completely unsafe; we will need to actually clone the 4790 /// expressions. 4791 Sema::OwningExprResult TransformExpr(Expr *E) { 4792 return getSema().Owned(E); 4793 } 4794 4795 /// \brief Transforms a typename type by determining whether the type now 4796 /// refers to a member of the current instantiation, and then 4797 /// type-checking and building a QualifiedNameType (when possible). 4798 QualType TransformTypenameType(TypeLocBuilder &TLB, TypenameTypeLoc TL); 4799 }; 4800} 4801 4802QualType 4803CurrentInstantiationRebuilder::TransformTypenameType(TypeLocBuilder &TLB, 4804 TypenameTypeLoc TL) { 4805 TypenameType *T = TL.getTypePtr(); 4806 4807 NestedNameSpecifier *NNS 4808 = TransformNestedNameSpecifier(T->getQualifier(), 4809 /*FIXME:*/SourceRange(getBaseLocation())); 4810 if (!NNS) 4811 return QualType(); 4812 4813 // If the nested-name-specifier did not change, and we cannot compute the 4814 // context corresponding to the nested-name-specifier, then this 4815 // typename type will not change; exit early. 4816 CXXScopeSpec SS; 4817 SS.setRange(SourceRange(getBaseLocation())); 4818 SS.setScopeRep(NNS); 4819 4820 QualType Result; 4821 if (NNS == T->getQualifier() && getSema().computeDeclContext(SS) == 0) 4822 Result = QualType(T, 0); 4823 4824 // Rebuild the typename type, which will probably turn into a 4825 // QualifiedNameType. 4826 else if (const TemplateSpecializationType *TemplateId = T->getTemplateId()) { 4827 QualType NewTemplateId 4828 = TransformType(QualType(TemplateId, 0)); 4829 if (NewTemplateId.isNull()) 4830 return QualType(); 4831 4832 if (NNS == T->getQualifier() && 4833 NewTemplateId == QualType(TemplateId, 0)) 4834 Result = QualType(T, 0); 4835 else 4836 Result = getDerived().RebuildTypenameType(NNS, NewTemplateId); 4837 } else 4838 Result = getDerived().RebuildTypenameType(NNS, T->getIdentifier(), 4839 SourceRange(TL.getNameLoc())); 4840 4841 TypenameTypeLoc NewTL = TLB.push<TypenameTypeLoc>(Result); 4842 NewTL.setNameLoc(TL.getNameLoc()); 4843 return Result; 4844} 4845 4846/// \brief Rebuilds a type within the context of the current instantiation. 4847/// 4848/// The type \p T is part of the type of an out-of-line member definition of 4849/// a class template (or class template partial specialization) that was parsed 4850/// and constructed before we entered the scope of the class template (or 4851/// partial specialization thereof). This routine will rebuild that type now 4852/// that we have entered the declarator's scope, which may produce different 4853/// canonical types, e.g., 4854/// 4855/// \code 4856/// template<typename T> 4857/// struct X { 4858/// typedef T* pointer; 4859/// pointer data(); 4860/// }; 4861/// 4862/// template<typename T> 4863/// typename X<T>::pointer X<T>::data() { ... } 4864/// \endcode 4865/// 4866/// Here, the type "typename X<T>::pointer" will be created as a TypenameType, 4867/// since we do not know that we can look into X<T> when we parsed the type. 4868/// This function will rebuild the type, performing the lookup of "pointer" 4869/// in X<T> and returning a QualifiedNameType whose canonical type is the same 4870/// as the canonical type of T*, allowing the return types of the out-of-line 4871/// definition and the declaration to match. 4872QualType Sema::RebuildTypeInCurrentInstantiation(QualType T, SourceLocation Loc, 4873 DeclarationName Name) { 4874 if (T.isNull() || !T->isDependentType()) 4875 return T; 4876 4877 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); 4878 return Rebuilder.TransformType(T); 4879} 4880 4881/// \brief Produces a formatted string that describes the binding of 4882/// template parameters to template arguments. 4883std::string 4884Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 4885 const TemplateArgumentList &Args) { 4886 // FIXME: For variadic templates, we'll need to get the structured list. 4887 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(), 4888 Args.flat_size()); 4889} 4890 4891std::string 4892Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 4893 const TemplateArgument *Args, 4894 unsigned NumArgs) { 4895 std::string Result; 4896 4897 if (!Params || Params->size() == 0 || NumArgs == 0) 4898 return Result; 4899 4900 for (unsigned I = 0, N = Params->size(); I != N; ++I) { 4901 if (I >= NumArgs) 4902 break; 4903 4904 if (I == 0) 4905 Result += "[with "; 4906 else 4907 Result += ", "; 4908 4909 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { 4910 Result += Id->getName(); 4911 } else { 4912 Result += '$'; 4913 Result += llvm::utostr(I); 4914 } 4915 4916 Result += " = "; 4917 4918 switch (Args[I].getKind()) { 4919 case TemplateArgument::Null: 4920 Result += "<no value>"; 4921 break; 4922 4923 case TemplateArgument::Type: { 4924 std::string TypeStr; 4925 Args[I].getAsType().getAsStringInternal(TypeStr, 4926 Context.PrintingPolicy); 4927 Result += TypeStr; 4928 break; 4929 } 4930 4931 case TemplateArgument::Declaration: { 4932 bool Unnamed = true; 4933 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) { 4934 if (ND->getDeclName()) { 4935 Unnamed = false; 4936 Result += ND->getNameAsString(); 4937 } 4938 } 4939 4940 if (Unnamed) { 4941 Result += "<anonymous>"; 4942 } 4943 break; 4944 } 4945 4946 case TemplateArgument::Template: { 4947 std::string Str; 4948 llvm::raw_string_ostream OS(Str); 4949 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy); 4950 Result += OS.str(); 4951 break; 4952 } 4953 4954 case TemplateArgument::Integral: { 4955 Result += Args[I].getAsIntegral()->toString(10); 4956 break; 4957 } 4958 4959 case TemplateArgument::Expression: { 4960 assert(false && "No expressions in deduced template arguments!"); 4961 Result += "<expression>"; 4962 break; 4963 } 4964 4965 case TemplateArgument::Pack: 4966 // FIXME: Format template argument packs 4967 Result += "<template argument pack>"; 4968 break; 4969 } 4970 } 4971 4972 Result += ']'; 4973 return Result; 4974} 4975