SemaTemplate.cpp revision 57b3f7533957905e360e48e5993a9e42f9c5a0c0
1//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/ 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7//===----------------------------------------------------------------------===/ 8// 9// This file implements semantic analysis for C++ templates. 10//===----------------------------------------------------------------------===/ 11 12#include "Sema.h" 13#include "Lookup.h" 14#include "TreeTransform.h" 15#include "clang/AST/ASTContext.h" 16#include "clang/AST/Expr.h" 17#include "clang/AST/ExprCXX.h" 18#include "clang/AST/DeclFriend.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/Parse/DeclSpec.h" 21#include "clang/Parse/Template.h" 22#include "clang/Basic/LangOptions.h" 23#include "clang/Basic/PartialDiagnostic.h" 24#include "llvm/ADT/StringExtras.h" 25using namespace clang; 26 27/// \brief Determine whether the declaration found is acceptable as the name 28/// of a template and, if so, return that template declaration. Otherwise, 29/// returns NULL. 30static NamedDecl *isAcceptableTemplateName(ASTContext &Context, NamedDecl *D) { 31 if (!D) 32 return 0; 33 34 if (isa<TemplateDecl>(D)) 35 return D; 36 37 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) { 38 // C++ [temp.local]p1: 39 // Like normal (non-template) classes, class templates have an 40 // injected-class-name (Clause 9). The injected-class-name 41 // can be used with or without a template-argument-list. When 42 // it is used without a template-argument-list, it is 43 // equivalent to the injected-class-name followed by the 44 // template-parameters of the class template enclosed in 45 // <>. When it is used with a template-argument-list, it 46 // refers to the specified class template specialization, 47 // which could be the current specialization or another 48 // specialization. 49 if (Record->isInjectedClassName()) { 50 Record = cast<CXXRecordDecl>(Record->getDeclContext()); 51 if (Record->getDescribedClassTemplate()) 52 return Record->getDescribedClassTemplate(); 53 54 if (ClassTemplateSpecializationDecl *Spec 55 = dyn_cast<ClassTemplateSpecializationDecl>(Record)) 56 return Spec->getSpecializedTemplate(); 57 } 58 59 return 0; 60 } 61 62 return 0; 63} 64 65static void FilterAcceptableTemplateNames(ASTContext &C, LookupResult &R) { 66 // The set of class templates we've already seen. 67 llvm::SmallPtrSet<ClassTemplateDecl *, 8> ClassTemplates; 68 LookupResult::Filter filter = R.makeFilter(); 69 while (filter.hasNext()) { 70 NamedDecl *Orig = filter.next(); 71 NamedDecl *Repl = isAcceptableTemplateName(C, Orig->getUnderlyingDecl()); 72 if (!Repl) 73 filter.erase(); 74 else if (Repl != Orig) { 75 76 // C++ [temp.local]p3: 77 // A lookup that finds an injected-class-name (10.2) can result in an 78 // ambiguity in certain cases (for example, if it is found in more than 79 // one base class). If all of the injected-class-names that are found 80 // refer to specializations of the same class template, and if the name 81 // is followed by a template-argument-list, the reference refers to the 82 // class template itself and not a specialization thereof, and is not 83 // ambiguous. 84 // 85 // FIXME: Will we eventually have to do the same for alias templates? 86 if (ClassTemplateDecl *ClassTmpl = dyn_cast<ClassTemplateDecl>(Repl)) 87 if (!ClassTemplates.insert(ClassTmpl)) { 88 filter.erase(); 89 continue; 90 } 91 92 filter.replace(Repl); 93 } 94 } 95 filter.done(); 96} 97 98TemplateNameKind Sema::isTemplateName(Scope *S, 99 CXXScopeSpec &SS, 100 UnqualifiedId &Name, 101 TypeTy *ObjectTypePtr, 102 bool EnteringContext, 103 TemplateTy &TemplateResult) { 104 assert(getLangOptions().CPlusPlus && "No template names in C!"); 105 106 DeclarationName TName; 107 108 switch (Name.getKind()) { 109 case UnqualifiedId::IK_Identifier: 110 TName = DeclarationName(Name.Identifier); 111 break; 112 113 case UnqualifiedId::IK_OperatorFunctionId: 114 TName = Context.DeclarationNames.getCXXOperatorName( 115 Name.OperatorFunctionId.Operator); 116 break; 117 118 case UnqualifiedId::IK_LiteralOperatorId: 119 TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier); 120 break; 121 122 default: 123 return TNK_Non_template; 124 } 125 126 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 127 128 LookupResult R(*this, TName, Name.getSourceRange().getBegin(), 129 LookupOrdinaryName); 130 R.suppressDiagnostics(); 131 LookupTemplateName(R, S, SS, ObjectType, EnteringContext); 132 if (R.empty() || R.isAmbiguous()) 133 return TNK_Non_template; 134 135 TemplateName Template; 136 TemplateNameKind TemplateKind; 137 138 unsigned ResultCount = R.end() - R.begin(); 139 if (ResultCount > 1) { 140 // We assume that we'll preserve the qualifier from a function 141 // template name in other ways. 142 Template = Context.getOverloadedTemplateName(R.begin(), R.end()); 143 TemplateKind = TNK_Function_template; 144 } else { 145 TemplateDecl *TD = cast<TemplateDecl>((*R.begin())->getUnderlyingDecl()); 146 147 if (SS.isSet() && !SS.isInvalid()) { 148 NestedNameSpecifier *Qualifier 149 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 150 Template = Context.getQualifiedTemplateName(Qualifier, false, TD); 151 } else { 152 Template = TemplateName(TD); 153 } 154 155 if (isa<FunctionTemplateDecl>(TD)) 156 TemplateKind = TNK_Function_template; 157 else { 158 assert(isa<ClassTemplateDecl>(TD) || isa<TemplateTemplateParmDecl>(TD)); 159 TemplateKind = TNK_Type_template; 160 } 161 } 162 163 TemplateResult = TemplateTy::make(Template); 164 return TemplateKind; 165} 166 167bool Sema::DiagnoseUnknownTemplateName(const IdentifierInfo &II, 168 SourceLocation IILoc, 169 Scope *S, 170 const CXXScopeSpec *SS, 171 TemplateTy &SuggestedTemplate, 172 TemplateNameKind &SuggestedKind) { 173 // We can't recover unless there's a dependent scope specifier preceding the 174 // template name. 175 if (!SS || !SS->isSet() || !isDependentScopeSpecifier(*SS) || 176 computeDeclContext(*SS)) 177 return false; 178 179 // The code is missing a 'template' keyword prior to the dependent template 180 // name. 181 NestedNameSpecifier *Qualifier = (NestedNameSpecifier*)SS->getScopeRep(); 182 Diag(IILoc, diag::err_template_kw_missing) 183 << Qualifier << II.getName() 184 << FixItHint::CreateInsertion(IILoc, "template "); 185 SuggestedTemplate 186 = TemplateTy::make(Context.getDependentTemplateName(Qualifier, &II)); 187 SuggestedKind = TNK_Dependent_template_name; 188 return true; 189} 190 191void Sema::LookupTemplateName(LookupResult &Found, 192 Scope *S, CXXScopeSpec &SS, 193 QualType ObjectType, 194 bool EnteringContext) { 195 // Determine where to perform name lookup 196 DeclContext *LookupCtx = 0; 197 bool isDependent = false; 198 if (!ObjectType.isNull()) { 199 // This nested-name-specifier occurs in a member access expression, e.g., 200 // x->B::f, and we are looking into the type of the object. 201 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 202 LookupCtx = computeDeclContext(ObjectType); 203 isDependent = ObjectType->isDependentType(); 204 assert((isDependent || !ObjectType->isIncompleteType()) && 205 "Caller should have completed object type"); 206 } else if (SS.isSet()) { 207 // This nested-name-specifier occurs after another nested-name-specifier, 208 // so long into the context associated with the prior nested-name-specifier. 209 LookupCtx = computeDeclContext(SS, EnteringContext); 210 isDependent = isDependentScopeSpecifier(SS); 211 212 // The declaration context must be complete. 213 if (LookupCtx && RequireCompleteDeclContext(SS)) 214 return; 215 } 216 217 bool ObjectTypeSearchedInScope = false; 218 if (LookupCtx) { 219 // Perform "qualified" name lookup into the declaration context we 220 // computed, which is either the type of the base of a member access 221 // expression or the declaration context associated with a prior 222 // nested-name-specifier. 223 LookupQualifiedName(Found, LookupCtx); 224 225 if (!ObjectType.isNull() && Found.empty()) { 226 // C++ [basic.lookup.classref]p1: 227 // In a class member access expression (5.2.5), if the . or -> token is 228 // immediately followed by an identifier followed by a <, the 229 // identifier must be looked up to determine whether the < is the 230 // beginning of a template argument list (14.2) or a less-than operator. 231 // The identifier is first looked up in the class of the object 232 // expression. If the identifier is not found, it is then looked up in 233 // the context of the entire postfix-expression and shall name a class 234 // or function template. 235 // 236 // FIXME: When we're instantiating a template, do we actually have to 237 // look in the scope of the template? Seems fishy... 238 if (S) LookupName(Found, S); 239 ObjectTypeSearchedInScope = true; 240 } 241 } else if (isDependent) { 242 // We cannot look into a dependent object type or nested nme 243 // specifier. 244 return; 245 } else { 246 // Perform unqualified name lookup in the current scope. 247 LookupName(Found, S); 248 } 249 250 if (Found.empty() && !isDependent) { 251 // If we did not find any names, attempt to correct any typos. 252 DeclarationName Name = Found.getLookupName(); 253 if (DeclarationName Corrected = CorrectTypo(Found, S, &SS, LookupCtx, 254 false, CTC_CXXCasts)) { 255 FilterAcceptableTemplateNames(Context, Found); 256 if (!Found.empty() && isa<TemplateDecl>(*Found.begin())) { 257 if (LookupCtx) 258 Diag(Found.getNameLoc(), diag::err_no_member_template_suggest) 259 << Name << LookupCtx << Found.getLookupName() << SS.getRange() 260 << FixItHint::CreateReplacement(Found.getNameLoc(), 261 Found.getLookupName().getAsString()); 262 else 263 Diag(Found.getNameLoc(), diag::err_no_template_suggest) 264 << Name << Found.getLookupName() 265 << FixItHint::CreateReplacement(Found.getNameLoc(), 266 Found.getLookupName().getAsString()); 267 if (TemplateDecl *Template = Found.getAsSingle<TemplateDecl>()) 268 Diag(Template->getLocation(), diag::note_previous_decl) 269 << Template->getDeclName(); 270 } else 271 Found.clear(); 272 } else { 273 Found.clear(); 274 } 275 } 276 277 FilterAcceptableTemplateNames(Context, Found); 278 if (Found.empty()) 279 return; 280 281 if (S && !ObjectType.isNull() && !ObjectTypeSearchedInScope) { 282 // C++ [basic.lookup.classref]p1: 283 // [...] If the lookup in the class of the object expression finds a 284 // template, the name is also looked up in the context of the entire 285 // postfix-expression and [...] 286 // 287 LookupResult FoundOuter(*this, Found.getLookupName(), Found.getNameLoc(), 288 LookupOrdinaryName); 289 LookupName(FoundOuter, S); 290 FilterAcceptableTemplateNames(Context, FoundOuter); 291 292 if (FoundOuter.empty()) { 293 // - if the name is not found, the name found in the class of the 294 // object expression is used, otherwise 295 } else if (!FoundOuter.getAsSingle<ClassTemplateDecl>()) { 296 // - if the name is found in the context of the entire 297 // postfix-expression and does not name a class template, the name 298 // found in the class of the object expression is used, otherwise 299 } else { 300 // - if the name found is a class template, it must refer to the same 301 // entity as the one found in the class of the object expression, 302 // otherwise the program is ill-formed. 303 if (!Found.isSingleResult() || 304 Found.getFoundDecl()->getCanonicalDecl() 305 != FoundOuter.getFoundDecl()->getCanonicalDecl()) { 306 Diag(Found.getNameLoc(), 307 diag::err_nested_name_member_ref_lookup_ambiguous) 308 << Found.getLookupName(); 309 Diag(Found.getRepresentativeDecl()->getLocation(), 310 diag::note_ambig_member_ref_object_type) 311 << ObjectType; 312 Diag(FoundOuter.getFoundDecl()->getLocation(), 313 diag::note_ambig_member_ref_scope); 314 315 // Recover by taking the template that we found in the object 316 // expression's type. 317 } 318 } 319 } 320} 321 322/// ActOnDependentIdExpression - Handle a dependent id-expression that 323/// was just parsed. This is only possible with an explicit scope 324/// specifier naming a dependent type. 325Sema::OwningExprResult 326Sema::ActOnDependentIdExpression(const CXXScopeSpec &SS, 327 DeclarationName Name, 328 SourceLocation NameLoc, 329 bool isAddressOfOperand, 330 const TemplateArgumentListInfo *TemplateArgs) { 331 NestedNameSpecifier *Qualifier 332 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 333 334 if (!isAddressOfOperand && 335 isa<CXXMethodDecl>(CurContext) && 336 cast<CXXMethodDecl>(CurContext)->isInstance()) { 337 QualType ThisType = cast<CXXMethodDecl>(CurContext)->getThisType(Context); 338 339 // Since the 'this' expression is synthesized, we don't need to 340 // perform the double-lookup check. 341 NamedDecl *FirstQualifierInScope = 0; 342 343 return Owned(CXXDependentScopeMemberExpr::Create(Context, 344 /*This*/ 0, ThisType, 345 /*IsArrow*/ true, 346 /*Op*/ SourceLocation(), 347 Qualifier, SS.getRange(), 348 FirstQualifierInScope, 349 Name, NameLoc, 350 TemplateArgs)); 351 } 352 353 return BuildDependentDeclRefExpr(SS, Name, NameLoc, TemplateArgs); 354} 355 356Sema::OwningExprResult 357Sema::BuildDependentDeclRefExpr(const CXXScopeSpec &SS, 358 DeclarationName Name, 359 SourceLocation NameLoc, 360 const TemplateArgumentListInfo *TemplateArgs) { 361 return Owned(DependentScopeDeclRefExpr::Create(Context, 362 static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 363 SS.getRange(), 364 Name, NameLoc, 365 TemplateArgs)); 366} 367 368/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining 369/// that the template parameter 'PrevDecl' is being shadowed by a new 370/// declaration at location Loc. Returns true to indicate that this is 371/// an error, and false otherwise. 372bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { 373 assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); 374 375 // Microsoft Visual C++ permits template parameters to be shadowed. 376 if (getLangOptions().Microsoft) 377 return false; 378 379 // C++ [temp.local]p4: 380 // A template-parameter shall not be redeclared within its 381 // scope (including nested scopes). 382 Diag(Loc, diag::err_template_param_shadow) 383 << cast<NamedDecl>(PrevDecl)->getDeclName(); 384 Diag(PrevDecl->getLocation(), diag::note_template_param_here); 385 return true; 386} 387 388/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset 389/// the parameter D to reference the templated declaration and return a pointer 390/// to the template declaration. Otherwise, do nothing to D and return null. 391TemplateDecl *Sema::AdjustDeclIfTemplate(DeclPtrTy &D) { 392 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D.getAs<Decl>())) { 393 D = DeclPtrTy::make(Temp->getTemplatedDecl()); 394 return Temp; 395 } 396 return 0; 397} 398 399static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, 400 const ParsedTemplateArgument &Arg) { 401 402 switch (Arg.getKind()) { 403 case ParsedTemplateArgument::Type: { 404 TypeSourceInfo *DI; 405 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); 406 if (!DI) 407 DI = SemaRef.Context.getTrivialTypeSourceInfo(T, Arg.getLocation()); 408 return TemplateArgumentLoc(TemplateArgument(T), DI); 409 } 410 411 case ParsedTemplateArgument::NonType: { 412 Expr *E = static_cast<Expr *>(Arg.getAsExpr()); 413 return TemplateArgumentLoc(TemplateArgument(E), E); 414 } 415 416 case ParsedTemplateArgument::Template: { 417 TemplateName Template 418 = TemplateName::getFromVoidPointer(Arg.getAsTemplate().get()); 419 return TemplateArgumentLoc(TemplateArgument(Template), 420 Arg.getScopeSpec().getRange(), 421 Arg.getLocation()); 422 } 423 } 424 425 llvm_unreachable("Unhandled parsed template argument"); 426 return TemplateArgumentLoc(); 427} 428 429/// \brief Translates template arguments as provided by the parser 430/// into template arguments used by semantic analysis. 431void Sema::translateTemplateArguments(const ASTTemplateArgsPtr &TemplateArgsIn, 432 TemplateArgumentListInfo &TemplateArgs) { 433 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) 434 TemplateArgs.addArgument(translateTemplateArgument(*this, 435 TemplateArgsIn[I])); 436} 437 438/// ActOnTypeParameter - Called when a C++ template type parameter 439/// (e.g., "typename T") has been parsed. Typename specifies whether 440/// the keyword "typename" was used to declare the type parameter 441/// (otherwise, "class" was used), and KeyLoc is the location of the 442/// "class" or "typename" keyword. ParamName is the name of the 443/// parameter (NULL indicates an unnamed template parameter) and 444/// ParamName is the location of the parameter name (if any). 445/// If the type parameter has a default argument, it will be added 446/// later via ActOnTypeParameterDefault. 447Sema::DeclPtrTy Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, 448 SourceLocation EllipsisLoc, 449 SourceLocation KeyLoc, 450 IdentifierInfo *ParamName, 451 SourceLocation ParamNameLoc, 452 unsigned Depth, unsigned Position) { 453 assert(S->isTemplateParamScope() && 454 "Template type parameter not in template parameter scope!"); 455 bool Invalid = false; 456 457 if (ParamName) { 458 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, LookupTagName); 459 if (PrevDecl && PrevDecl->isTemplateParameter()) 460 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc, 461 PrevDecl); 462 } 463 464 SourceLocation Loc = ParamNameLoc; 465 if (!ParamName) 466 Loc = KeyLoc; 467 468 TemplateTypeParmDecl *Param 469 = TemplateTypeParmDecl::Create(Context, Context.getTranslationUnitDecl(), 470 Loc, Depth, Position, ParamName, Typename, 471 Ellipsis); 472 if (Invalid) 473 Param->setInvalidDecl(); 474 475 if (ParamName) { 476 // Add the template parameter into the current scope. 477 S->AddDecl(DeclPtrTy::make(Param)); 478 IdResolver.AddDecl(Param); 479 } 480 481 return DeclPtrTy::make(Param); 482} 483 484/// ActOnTypeParameterDefault - Adds a default argument (the type 485/// Default) to the given template type parameter (TypeParam). 486void Sema::ActOnTypeParameterDefault(DeclPtrTy TypeParam, 487 SourceLocation EqualLoc, 488 SourceLocation DefaultLoc, 489 TypeTy *DefaultT) { 490 TemplateTypeParmDecl *Parm 491 = cast<TemplateTypeParmDecl>(TypeParam.getAs<Decl>()); 492 493 TypeSourceInfo *DefaultTInfo; 494 GetTypeFromParser(DefaultT, &DefaultTInfo); 495 496 assert(DefaultTInfo && "expected source information for type"); 497 498 // C++0x [temp.param]p9: 499 // A default template-argument may be specified for any kind of 500 // template-parameter that is not a template parameter pack. 501 if (Parm->isParameterPack()) { 502 Diag(DefaultLoc, diag::err_template_param_pack_default_arg); 503 return; 504 } 505 506 // C++ [temp.param]p14: 507 // A template-parameter shall not be used in its own default argument. 508 // FIXME: Implement this check! Needs a recursive walk over the types. 509 510 // Check the template argument itself. 511 if (CheckTemplateArgument(Parm, DefaultTInfo)) { 512 Parm->setInvalidDecl(); 513 return; 514 } 515 516 Parm->setDefaultArgument(DefaultTInfo, false); 517} 518 519/// \brief Check that the type of a non-type template parameter is 520/// well-formed. 521/// 522/// \returns the (possibly-promoted) parameter type if valid; 523/// otherwise, produces a diagnostic and returns a NULL type. 524QualType 525Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { 526 // C++ [temp.param]p4: 527 // 528 // A non-type template-parameter shall have one of the following 529 // (optionally cv-qualified) types: 530 // 531 // -- integral or enumeration type, 532 if (T->isIntegralType() || T->isEnumeralType() || 533 // -- pointer to object or pointer to function, 534 (T->isPointerType() && 535 (T->getAs<PointerType>()->getPointeeType()->isObjectType() || 536 T->getAs<PointerType>()->getPointeeType()->isFunctionType())) || 537 // -- reference to object or reference to function, 538 T->isReferenceType() || 539 // -- pointer to member. 540 T->isMemberPointerType() || 541 // If T is a dependent type, we can't do the check now, so we 542 // assume that it is well-formed. 543 T->isDependentType()) 544 return T; 545 // C++ [temp.param]p8: 546 // 547 // A non-type template-parameter of type "array of T" or 548 // "function returning T" is adjusted to be of type "pointer to 549 // T" or "pointer to function returning T", respectively. 550 else if (T->isArrayType()) 551 // FIXME: Keep the type prior to promotion? 552 return Context.getArrayDecayedType(T); 553 else if (T->isFunctionType()) 554 // FIXME: Keep the type prior to promotion? 555 return Context.getPointerType(T); 556 557 Diag(Loc, diag::err_template_nontype_parm_bad_type) 558 << T; 559 560 return QualType(); 561} 562 563/// ActOnNonTypeTemplateParameter - Called when a C++ non-type 564/// template parameter (e.g., "int Size" in "template<int Size> 565/// class Array") has been parsed. S is the current scope and D is 566/// the parsed declarator. 567Sema::DeclPtrTy Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, 568 unsigned Depth, 569 unsigned Position) { 570 TypeSourceInfo *TInfo = 0; 571 QualType T = GetTypeForDeclarator(D, S, &TInfo); 572 573 assert(S->isTemplateParamScope() && 574 "Non-type template parameter not in template parameter scope!"); 575 bool Invalid = false; 576 577 IdentifierInfo *ParamName = D.getIdentifier(); 578 if (ParamName) { 579 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, LookupTagName); 580 if (PrevDecl && PrevDecl->isTemplateParameter()) 581 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 582 PrevDecl); 583 } 584 585 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); 586 if (T.isNull()) { 587 T = Context.IntTy; // Recover with an 'int' type. 588 Invalid = true; 589 } 590 591 NonTypeTemplateParmDecl *Param 592 = NonTypeTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 593 D.getIdentifierLoc(), 594 Depth, Position, ParamName, T, TInfo); 595 if (Invalid) 596 Param->setInvalidDecl(); 597 598 if (D.getIdentifier()) { 599 // Add the template parameter into the current scope. 600 S->AddDecl(DeclPtrTy::make(Param)); 601 IdResolver.AddDecl(Param); 602 } 603 return DeclPtrTy::make(Param); 604} 605 606/// \brief Adds a default argument to the given non-type template 607/// parameter. 608void Sema::ActOnNonTypeTemplateParameterDefault(DeclPtrTy TemplateParamD, 609 SourceLocation EqualLoc, 610 ExprArg DefaultE) { 611 NonTypeTemplateParmDecl *TemplateParm 612 = cast<NonTypeTemplateParmDecl>(TemplateParamD.getAs<Decl>()); 613 Expr *Default = static_cast<Expr *>(DefaultE.get()); 614 615 // C++ [temp.param]p14: 616 // A template-parameter shall not be used in its own default argument. 617 // FIXME: Implement this check! Needs a recursive walk over the types. 618 619 // Check the well-formedness of the default template argument. 620 TemplateArgument Converted; 621 if (CheckTemplateArgument(TemplateParm, TemplateParm->getType(), Default, 622 Converted)) { 623 TemplateParm->setInvalidDecl(); 624 return; 625 } 626 627 TemplateParm->setDefaultArgument(DefaultE.takeAs<Expr>()); 628} 629 630 631/// ActOnTemplateTemplateParameter - Called when a C++ template template 632/// parameter (e.g. T in template <template <typename> class T> class array) 633/// has been parsed. S is the current scope. 634Sema::DeclPtrTy Sema::ActOnTemplateTemplateParameter(Scope* S, 635 SourceLocation TmpLoc, 636 TemplateParamsTy *Params, 637 IdentifierInfo *Name, 638 SourceLocation NameLoc, 639 unsigned Depth, 640 unsigned Position) { 641 assert(S->isTemplateParamScope() && 642 "Template template parameter not in template parameter scope!"); 643 644 // Construct the parameter object. 645 TemplateTemplateParmDecl *Param = 646 TemplateTemplateParmDecl::Create(Context, Context.getTranslationUnitDecl(), 647 TmpLoc, Depth, Position, Name, 648 (TemplateParameterList*)Params); 649 650 // Make sure the parameter is valid. 651 // FIXME: Decl object is not currently invalidated anywhere so this doesn't 652 // do anything yet. However, if the template parameter list or (eventual) 653 // default value is ever invalidated, that will propagate here. 654 bool Invalid = false; 655 if (Invalid) { 656 Param->setInvalidDecl(); 657 } 658 659 // If the tt-param has a name, then link the identifier into the scope 660 // and lookup mechanisms. 661 if (Name) { 662 S->AddDecl(DeclPtrTy::make(Param)); 663 IdResolver.AddDecl(Param); 664 } 665 666 return DeclPtrTy::make(Param); 667} 668 669/// \brief Adds a default argument to the given template template 670/// parameter. 671void Sema::ActOnTemplateTemplateParameterDefault(DeclPtrTy TemplateParamD, 672 SourceLocation EqualLoc, 673 const ParsedTemplateArgument &Default) { 674 TemplateTemplateParmDecl *TemplateParm 675 = cast<TemplateTemplateParmDecl>(TemplateParamD.getAs<Decl>()); 676 677 // C++ [temp.param]p14: 678 // A template-parameter shall not be used in its own default argument. 679 // FIXME: Implement this check! Needs a recursive walk over the types. 680 681 // Check only that we have a template template argument. We don't want to 682 // try to check well-formedness now, because our template template parameter 683 // might have dependent types in its template parameters, which we wouldn't 684 // be able to match now. 685 // 686 // If none of the template template parameter's template arguments mention 687 // other template parameters, we could actually perform more checking here. 688 // However, it isn't worth doing. 689 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); 690 if (DefaultArg.getArgument().getAsTemplate().isNull()) { 691 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) 692 << DefaultArg.getSourceRange(); 693 return; 694 } 695 696 TemplateParm->setDefaultArgument(DefaultArg); 697} 698 699/// ActOnTemplateParameterList - Builds a TemplateParameterList that 700/// contains the template parameters in Params/NumParams. 701Sema::TemplateParamsTy * 702Sema::ActOnTemplateParameterList(unsigned Depth, 703 SourceLocation ExportLoc, 704 SourceLocation TemplateLoc, 705 SourceLocation LAngleLoc, 706 DeclPtrTy *Params, unsigned NumParams, 707 SourceLocation RAngleLoc) { 708 if (ExportLoc.isValid()) 709 Diag(ExportLoc, diag::warn_template_export_unsupported); 710 711 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, 712 (NamedDecl**)Params, NumParams, 713 RAngleLoc); 714} 715 716static void SetNestedNameSpecifier(TagDecl *T, const CXXScopeSpec &SS) { 717 if (SS.isSet()) 718 T->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 719 SS.getRange()); 720} 721 722Sema::DeclResult 723Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, 724 SourceLocation KWLoc, CXXScopeSpec &SS, 725 IdentifierInfo *Name, SourceLocation NameLoc, 726 AttributeList *Attr, 727 TemplateParameterList *TemplateParams, 728 AccessSpecifier AS) { 729 assert(TemplateParams && TemplateParams->size() > 0 && 730 "No template parameters"); 731 assert(TUK != TUK_Reference && "Can only declare or define class templates"); 732 bool Invalid = false; 733 734 // Check that we can declare a template here. 735 if (CheckTemplateDeclScope(S, TemplateParams)) 736 return true; 737 738 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 739 assert(Kind != TagDecl::TK_enum && "can't build template of enumerated type"); 740 741 // There is no such thing as an unnamed class template. 742 if (!Name) { 743 Diag(KWLoc, diag::err_template_unnamed_class); 744 return true; 745 } 746 747 // Find any previous declaration with this name. 748 DeclContext *SemanticContext; 749 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, 750 ForRedeclaration); 751 if (SS.isNotEmpty() && !SS.isInvalid()) { 752 if (RequireCompleteDeclContext(SS)) 753 return true; 754 755 SemanticContext = computeDeclContext(SS, true); 756 if (!SemanticContext) { 757 // FIXME: Produce a reasonable diagnostic here 758 return true; 759 } 760 761 LookupQualifiedName(Previous, SemanticContext); 762 } else { 763 SemanticContext = CurContext; 764 LookupName(Previous, S); 765 } 766 767 if (Previous.isAmbiguous()) 768 return true; 769 770 NamedDecl *PrevDecl = 0; 771 if (Previous.begin() != Previous.end()) 772 PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 773 774 // If there is a previous declaration with the same name, check 775 // whether this is a valid redeclaration. 776 ClassTemplateDecl *PrevClassTemplate 777 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); 778 779 // We may have found the injected-class-name of a class template, 780 // class template partial specialization, or class template specialization. 781 // In these cases, grab the template that is being defined or specialized. 782 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && 783 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { 784 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); 785 PrevClassTemplate 786 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); 787 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { 788 PrevClassTemplate 789 = cast<ClassTemplateSpecializationDecl>(PrevDecl) 790 ->getSpecializedTemplate(); 791 } 792 } 793 794 if (TUK == TUK_Friend) { 795 // C++ [namespace.memdef]p3: 796 // [...] When looking for a prior declaration of a class or a function 797 // declared as a friend, and when the name of the friend class or 798 // function is neither a qualified name nor a template-id, scopes outside 799 // the innermost enclosing namespace scope are not considered. 800 DeclContext *OutermostContext = CurContext; 801 while (!OutermostContext->isFileContext()) 802 OutermostContext = OutermostContext->getLookupParent(); 803 804 if (PrevDecl && 805 (OutermostContext->Equals(PrevDecl->getDeclContext()) || 806 OutermostContext->Encloses(PrevDecl->getDeclContext()))) { 807 SemanticContext = PrevDecl->getDeclContext(); 808 } else { 809 // Declarations in outer scopes don't matter. However, the outermost 810 // context we computed is the semantic context for our new 811 // declaration. 812 PrevDecl = PrevClassTemplate = 0; 813 SemanticContext = OutermostContext; 814 } 815 816 if (CurContext->isDependentContext()) { 817 // If this is a dependent context, we don't want to link the friend 818 // class template to the template in scope, because that would perform 819 // checking of the template parameter lists that can't be performed 820 // until the outer context is instantiated. 821 PrevDecl = PrevClassTemplate = 0; 822 } 823 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) 824 PrevDecl = PrevClassTemplate = 0; 825 826 if (PrevClassTemplate) { 827 // Ensure that the template parameter lists are compatible. 828 if (!TemplateParameterListsAreEqual(TemplateParams, 829 PrevClassTemplate->getTemplateParameters(), 830 /*Complain=*/true, 831 TPL_TemplateMatch)) 832 return true; 833 834 // C++ [temp.class]p4: 835 // In a redeclaration, partial specialization, explicit 836 // specialization or explicit instantiation of a class template, 837 // the class-key shall agree in kind with the original class 838 // template declaration (7.1.5.3). 839 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); 840 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) { 841 Diag(KWLoc, diag::err_use_with_wrong_tag) 842 << Name 843 << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName()); 844 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); 845 Kind = PrevRecordDecl->getTagKind(); 846 } 847 848 // Check for redefinition of this class template. 849 if (TUK == TUK_Definition) { 850 if (TagDecl *Def = PrevRecordDecl->getDefinition()) { 851 Diag(NameLoc, diag::err_redefinition) << Name; 852 Diag(Def->getLocation(), diag::note_previous_definition); 853 // FIXME: Would it make sense to try to "forget" the previous 854 // definition, as part of error recovery? 855 return true; 856 } 857 } 858 } else if (PrevDecl && PrevDecl->isTemplateParameter()) { 859 // Maybe we will complain about the shadowed template parameter. 860 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 861 // Just pretend that we didn't see the previous declaration. 862 PrevDecl = 0; 863 } else if (PrevDecl) { 864 // C++ [temp]p5: 865 // A class template shall not have the same name as any other 866 // template, class, function, object, enumeration, enumerator, 867 // namespace, or type in the same scope (3.3), except as specified 868 // in (14.5.4). 869 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 870 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 871 return true; 872 } 873 874 // Check the template parameter list of this declaration, possibly 875 // merging in the template parameter list from the previous class 876 // template declaration. 877 if (CheckTemplateParameterList(TemplateParams, 878 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0, 879 TPC_ClassTemplate)) 880 Invalid = true; 881 882 if (SS.isSet()) { 883 // If the name of the template was qualified, we must be defining the 884 // template out-of-line. 885 if (!SS.isInvalid() && !Invalid && !PrevClassTemplate && 886 !(TUK == TUK_Friend && CurContext->isDependentContext())) 887 Diag(NameLoc, diag::err_member_def_does_not_match) 888 << Name << SemanticContext << SS.getRange(); 889 } 890 891 CXXRecordDecl *NewClass = 892 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc, 893 PrevClassTemplate? 894 PrevClassTemplate->getTemplatedDecl() : 0, 895 /*DelayTypeCreation=*/true); 896 SetNestedNameSpecifier(NewClass, SS); 897 898 ClassTemplateDecl *NewTemplate 899 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, 900 DeclarationName(Name), TemplateParams, 901 NewClass, PrevClassTemplate); 902 NewClass->setDescribedClassTemplate(NewTemplate); 903 904 // Build the type for the class template declaration now. 905 QualType T = NewTemplate->getInjectedClassNameSpecialization(Context); 906 T = Context.getInjectedClassNameType(NewClass, T); 907 assert(T->isDependentType() && "Class template type is not dependent?"); 908 (void)T; 909 910 // If we are providing an explicit specialization of a member that is a 911 // class template, make a note of that. 912 if (PrevClassTemplate && 913 PrevClassTemplate->getInstantiatedFromMemberTemplate()) 914 PrevClassTemplate->setMemberSpecialization(); 915 916 // Set the access specifier. 917 if (!Invalid && TUK != TUK_Friend) 918 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); 919 920 // Set the lexical context of these templates 921 NewClass->setLexicalDeclContext(CurContext); 922 NewTemplate->setLexicalDeclContext(CurContext); 923 924 if (TUK == TUK_Definition) 925 NewClass->startDefinition(); 926 927 if (Attr) 928 ProcessDeclAttributeList(S, NewClass, Attr); 929 930 if (TUK != TUK_Friend) 931 PushOnScopeChains(NewTemplate, S); 932 else { 933 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { 934 NewTemplate->setAccess(PrevClassTemplate->getAccess()); 935 NewClass->setAccess(PrevClassTemplate->getAccess()); 936 } 937 938 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ 939 PrevClassTemplate != NULL); 940 941 // Friend templates are visible in fairly strange ways. 942 if (!CurContext->isDependentContext()) { 943 DeclContext *DC = SemanticContext->getLookupContext(); 944 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false); 945 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 946 PushOnScopeChains(NewTemplate, EnclosingScope, 947 /* AddToContext = */ false); 948 } 949 950 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 951 NewClass->getLocation(), 952 NewTemplate, 953 /*FIXME:*/NewClass->getLocation()); 954 Friend->setAccess(AS_public); 955 CurContext->addDecl(Friend); 956 } 957 958 if (Invalid) { 959 NewTemplate->setInvalidDecl(); 960 NewClass->setInvalidDecl(); 961 } 962 return DeclPtrTy::make(NewTemplate); 963} 964 965/// \brief Diagnose the presence of a default template argument on a 966/// template parameter, which is ill-formed in certain contexts. 967/// 968/// \returns true if the default template argument should be dropped. 969static bool DiagnoseDefaultTemplateArgument(Sema &S, 970 Sema::TemplateParamListContext TPC, 971 SourceLocation ParamLoc, 972 SourceRange DefArgRange) { 973 switch (TPC) { 974 case Sema::TPC_ClassTemplate: 975 return false; 976 977 case Sema::TPC_FunctionTemplate: 978 // C++ [temp.param]p9: 979 // A default template-argument shall not be specified in a 980 // function template declaration or a function template 981 // definition [...] 982 // (This sentence is not in C++0x, per DR226). 983 if (!S.getLangOptions().CPlusPlus0x) 984 S.Diag(ParamLoc, 985 diag::err_template_parameter_default_in_function_template) 986 << DefArgRange; 987 return false; 988 989 case Sema::TPC_ClassTemplateMember: 990 // C++0x [temp.param]p9: 991 // A default template-argument shall not be specified in the 992 // template-parameter-lists of the definition of a member of a 993 // class template that appears outside of the member's class. 994 S.Diag(ParamLoc, diag::err_template_parameter_default_template_member) 995 << DefArgRange; 996 return true; 997 998 case Sema::TPC_FriendFunctionTemplate: 999 // C++ [temp.param]p9: 1000 // A default template-argument shall not be specified in a 1001 // friend template declaration. 1002 S.Diag(ParamLoc, diag::err_template_parameter_default_friend_template) 1003 << DefArgRange; 1004 return true; 1005 1006 // FIXME: C++0x [temp.param]p9 allows default template-arguments 1007 // for friend function templates if there is only a single 1008 // declaration (and it is a definition). Strange! 1009 } 1010 1011 return false; 1012} 1013 1014/// \brief Checks the validity of a template parameter list, possibly 1015/// considering the template parameter list from a previous 1016/// declaration. 1017/// 1018/// If an "old" template parameter list is provided, it must be 1019/// equivalent (per TemplateParameterListsAreEqual) to the "new" 1020/// template parameter list. 1021/// 1022/// \param NewParams Template parameter list for a new template 1023/// declaration. This template parameter list will be updated with any 1024/// default arguments that are carried through from the previous 1025/// template parameter list. 1026/// 1027/// \param OldParams If provided, template parameter list from a 1028/// previous declaration of the same template. Default template 1029/// arguments will be merged from the old template parameter list to 1030/// the new template parameter list. 1031/// 1032/// \param TPC Describes the context in which we are checking the given 1033/// template parameter list. 1034/// 1035/// \returns true if an error occurred, false otherwise. 1036bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, 1037 TemplateParameterList *OldParams, 1038 TemplateParamListContext TPC) { 1039 bool Invalid = false; 1040 1041 // C++ [temp.param]p10: 1042 // The set of default template-arguments available for use with a 1043 // template declaration or definition is obtained by merging the 1044 // default arguments from the definition (if in scope) and all 1045 // declarations in scope in the same way default function 1046 // arguments are (8.3.6). 1047 bool SawDefaultArgument = false; 1048 SourceLocation PreviousDefaultArgLoc; 1049 1050 bool SawParameterPack = false; 1051 SourceLocation ParameterPackLoc; 1052 1053 // Dummy initialization to avoid warnings. 1054 TemplateParameterList::iterator OldParam = NewParams->end(); 1055 if (OldParams) 1056 OldParam = OldParams->begin(); 1057 1058 for (TemplateParameterList::iterator NewParam = NewParams->begin(), 1059 NewParamEnd = NewParams->end(); 1060 NewParam != NewParamEnd; ++NewParam) { 1061 // Variables used to diagnose redundant default arguments 1062 bool RedundantDefaultArg = false; 1063 SourceLocation OldDefaultLoc; 1064 SourceLocation NewDefaultLoc; 1065 1066 // Variables used to diagnose missing default arguments 1067 bool MissingDefaultArg = false; 1068 1069 // C++0x [temp.param]p11: 1070 // If a template parameter of a class template is a template parameter pack, 1071 // it must be the last template parameter. 1072 if (SawParameterPack) { 1073 Diag(ParameterPackLoc, 1074 diag::err_template_param_pack_must_be_last_template_parameter); 1075 Invalid = true; 1076 } 1077 1078 if (TemplateTypeParmDecl *NewTypeParm 1079 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { 1080 // Check the presence of a default argument here. 1081 if (NewTypeParm->hasDefaultArgument() && 1082 DiagnoseDefaultTemplateArgument(*this, TPC, 1083 NewTypeParm->getLocation(), 1084 NewTypeParm->getDefaultArgumentInfo()->getTypeLoc() 1085 .getFullSourceRange())) 1086 NewTypeParm->removeDefaultArgument(); 1087 1088 // Merge default arguments for template type parameters. 1089 TemplateTypeParmDecl *OldTypeParm 1090 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; 1091 1092 if (NewTypeParm->isParameterPack()) { 1093 assert(!NewTypeParm->hasDefaultArgument() && 1094 "Parameter packs can't have a default argument!"); 1095 SawParameterPack = true; 1096 ParameterPackLoc = NewTypeParm->getLocation(); 1097 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && 1098 NewTypeParm->hasDefaultArgument()) { 1099 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); 1100 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); 1101 SawDefaultArgument = true; 1102 RedundantDefaultArg = true; 1103 PreviousDefaultArgLoc = NewDefaultLoc; 1104 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { 1105 // Merge the default argument from the old declaration to the 1106 // new declaration. 1107 SawDefaultArgument = true; 1108 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), 1109 true); 1110 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); 1111 } else if (NewTypeParm->hasDefaultArgument()) { 1112 SawDefaultArgument = true; 1113 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); 1114 } else if (SawDefaultArgument) 1115 MissingDefaultArg = true; 1116 } else if (NonTypeTemplateParmDecl *NewNonTypeParm 1117 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { 1118 // Check the presence of a default argument here. 1119 if (NewNonTypeParm->hasDefaultArgument() && 1120 DiagnoseDefaultTemplateArgument(*this, TPC, 1121 NewNonTypeParm->getLocation(), 1122 NewNonTypeParm->getDefaultArgument()->getSourceRange())) { 1123 NewNonTypeParm->getDefaultArgument()->Destroy(Context); 1124 NewNonTypeParm->setDefaultArgument(0); 1125 } 1126 1127 // Merge default arguments for non-type template parameters 1128 NonTypeTemplateParmDecl *OldNonTypeParm 1129 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; 1130 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && 1131 NewNonTypeParm->hasDefaultArgument()) { 1132 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1133 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1134 SawDefaultArgument = true; 1135 RedundantDefaultArg = true; 1136 PreviousDefaultArgLoc = NewDefaultLoc; 1137 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { 1138 // Merge the default argument from the old declaration to the 1139 // new declaration. 1140 SawDefaultArgument = true; 1141 // FIXME: We need to create a new kind of "default argument" 1142 // expression that points to a previous template template 1143 // parameter. 1144 NewNonTypeParm->setDefaultArgument( 1145 OldNonTypeParm->getDefaultArgument()); 1146 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); 1147 } else if (NewNonTypeParm->hasDefaultArgument()) { 1148 SawDefaultArgument = true; 1149 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); 1150 } else if (SawDefaultArgument) 1151 MissingDefaultArg = true; 1152 } else { 1153 // Check the presence of a default argument here. 1154 TemplateTemplateParmDecl *NewTemplateParm 1155 = cast<TemplateTemplateParmDecl>(*NewParam); 1156 if (NewTemplateParm->hasDefaultArgument() && 1157 DiagnoseDefaultTemplateArgument(*this, TPC, 1158 NewTemplateParm->getLocation(), 1159 NewTemplateParm->getDefaultArgument().getSourceRange())) 1160 NewTemplateParm->setDefaultArgument(TemplateArgumentLoc()); 1161 1162 // Merge default arguments for template template parameters 1163 TemplateTemplateParmDecl *OldTemplateParm 1164 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; 1165 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && 1166 NewTemplateParm->hasDefaultArgument()) { 1167 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); 1168 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); 1169 SawDefaultArgument = true; 1170 RedundantDefaultArg = true; 1171 PreviousDefaultArgLoc = NewDefaultLoc; 1172 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { 1173 // Merge the default argument from the old declaration to the 1174 // new declaration. 1175 SawDefaultArgument = true; 1176 // FIXME: We need to create a new kind of "default argument" expression 1177 // that points to a previous template template parameter. 1178 NewTemplateParm->setDefaultArgument( 1179 OldTemplateParm->getDefaultArgument()); 1180 PreviousDefaultArgLoc 1181 = OldTemplateParm->getDefaultArgument().getLocation(); 1182 } else if (NewTemplateParm->hasDefaultArgument()) { 1183 SawDefaultArgument = true; 1184 PreviousDefaultArgLoc 1185 = NewTemplateParm->getDefaultArgument().getLocation(); 1186 } else if (SawDefaultArgument) 1187 MissingDefaultArg = true; 1188 } 1189 1190 if (RedundantDefaultArg) { 1191 // C++ [temp.param]p12: 1192 // A template-parameter shall not be given default arguments 1193 // by two different declarations in the same scope. 1194 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); 1195 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); 1196 Invalid = true; 1197 } else if (MissingDefaultArg) { 1198 // C++ [temp.param]p11: 1199 // If a template-parameter has a default template-argument, 1200 // all subsequent template-parameters shall have a default 1201 // template-argument supplied. 1202 Diag((*NewParam)->getLocation(), 1203 diag::err_template_param_default_arg_missing); 1204 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); 1205 Invalid = true; 1206 } 1207 1208 // If we have an old template parameter list that we're merging 1209 // in, move on to the next parameter. 1210 if (OldParams) 1211 ++OldParam; 1212 } 1213 1214 return Invalid; 1215} 1216 1217/// \brief Match the given template parameter lists to the given scope 1218/// specifier, returning the template parameter list that applies to the 1219/// name. 1220/// 1221/// \param DeclStartLoc the start of the declaration that has a scope 1222/// specifier or a template parameter list. 1223/// 1224/// \param SS the scope specifier that will be matched to the given template 1225/// parameter lists. This scope specifier precedes a qualified name that is 1226/// being declared. 1227/// 1228/// \param ParamLists the template parameter lists, from the outermost to the 1229/// innermost template parameter lists. 1230/// 1231/// \param NumParamLists the number of template parameter lists in ParamLists. 1232/// 1233/// \param IsFriend Whether to apply the slightly different rules for 1234/// matching template parameters to scope specifiers in friend 1235/// declarations. 1236/// 1237/// \param IsExplicitSpecialization will be set true if the entity being 1238/// declared is an explicit specialization, false otherwise. 1239/// 1240/// \returns the template parameter list, if any, that corresponds to the 1241/// name that is preceded by the scope specifier @p SS. This template 1242/// parameter list may be have template parameters (if we're declaring a 1243/// template) or may have no template parameters (if we're declaring a 1244/// template specialization), or may be NULL (if we were's declaring isn't 1245/// itself a template). 1246TemplateParameterList * 1247Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, 1248 const CXXScopeSpec &SS, 1249 TemplateParameterList **ParamLists, 1250 unsigned NumParamLists, 1251 bool IsFriend, 1252 bool &IsExplicitSpecialization) { 1253 IsExplicitSpecialization = false; 1254 1255 // Find the template-ids that occur within the nested-name-specifier. These 1256 // template-ids will match up with the template parameter lists. 1257 llvm::SmallVector<const TemplateSpecializationType *, 4> 1258 TemplateIdsInSpecifier; 1259 llvm::SmallVector<ClassTemplateSpecializationDecl *, 4> 1260 ExplicitSpecializationsInSpecifier; 1261 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 1262 NNS; NNS = NNS->getPrefix()) { 1263 const Type *T = NNS->getAsType(); 1264 if (!T) break; 1265 1266 // C++0x [temp.expl.spec]p17: 1267 // A member or a member template may be nested within many 1268 // enclosing class templates. In an explicit specialization for 1269 // such a member, the member declaration shall be preceded by a 1270 // template<> for each enclosing class template that is 1271 // explicitly specialized. 1272 // 1273 // Following the existing practice of GNU and EDG, we allow a typedef of a 1274 // template specialization type. 1275 if (const TypedefType *TT = dyn_cast<TypedefType>(T)) 1276 T = TT->LookThroughTypedefs().getTypePtr(); 1277 1278 if (const TemplateSpecializationType *SpecType 1279 = dyn_cast<TemplateSpecializationType>(T)) { 1280 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl(); 1281 if (!Template) 1282 continue; // FIXME: should this be an error? probably... 1283 1284 if (const RecordType *Record = SpecType->getAs<RecordType>()) { 1285 ClassTemplateSpecializationDecl *SpecDecl 1286 = cast<ClassTemplateSpecializationDecl>(Record->getDecl()); 1287 // If the nested name specifier refers to an explicit specialization, 1288 // we don't need a template<> header. 1289 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) { 1290 ExplicitSpecializationsInSpecifier.push_back(SpecDecl); 1291 continue; 1292 } 1293 } 1294 1295 TemplateIdsInSpecifier.push_back(SpecType); 1296 } 1297 } 1298 1299 // Reverse the list of template-ids in the scope specifier, so that we can 1300 // more easily match up the template-ids and the template parameter lists. 1301 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end()); 1302 1303 SourceLocation FirstTemplateLoc = DeclStartLoc; 1304 if (NumParamLists) 1305 FirstTemplateLoc = ParamLists[0]->getTemplateLoc(); 1306 1307 // Match the template-ids found in the specifier to the template parameter 1308 // lists. 1309 unsigned Idx = 0; 1310 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size(); 1311 Idx != NumTemplateIds; ++Idx) { 1312 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0); 1313 bool DependentTemplateId = TemplateId->isDependentType(); 1314 if (Idx >= NumParamLists) { 1315 // We have a template-id without a corresponding template parameter 1316 // list. 1317 1318 // ...which is fine if this is a friend declaration. 1319 if (IsFriend) { 1320 IsExplicitSpecialization = true; 1321 break; 1322 } 1323 1324 if (DependentTemplateId) { 1325 // FIXME: the location information here isn't great. 1326 Diag(SS.getRange().getBegin(), 1327 diag::err_template_spec_needs_template_parameters) 1328 << TemplateId 1329 << SS.getRange(); 1330 } else { 1331 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header) 1332 << SS.getRange() 1333 << FixItHint::CreateInsertion(FirstTemplateLoc, "template<> "); 1334 IsExplicitSpecialization = true; 1335 } 1336 return 0; 1337 } 1338 1339 // Check the template parameter list against its corresponding template-id. 1340 if (DependentTemplateId) { 1341 TemplateDecl *Template 1342 = TemplateIdsInSpecifier[Idx]->getTemplateName().getAsTemplateDecl(); 1343 1344 if (ClassTemplateDecl *ClassTemplate 1345 = dyn_cast<ClassTemplateDecl>(Template)) { 1346 TemplateParameterList *ExpectedTemplateParams = 0; 1347 // Is this template-id naming the primary template? 1348 if (Context.hasSameType(TemplateId, 1349 ClassTemplate->getInjectedClassNameSpecialization(Context))) 1350 ExpectedTemplateParams = ClassTemplate->getTemplateParameters(); 1351 // ... or a partial specialization? 1352 else if (ClassTemplatePartialSpecializationDecl *PartialSpec 1353 = ClassTemplate->findPartialSpecialization(TemplateId)) 1354 ExpectedTemplateParams = PartialSpec->getTemplateParameters(); 1355 1356 if (ExpectedTemplateParams) 1357 TemplateParameterListsAreEqual(ParamLists[Idx], 1358 ExpectedTemplateParams, 1359 true, TPL_TemplateMatch); 1360 } 1361 1362 CheckTemplateParameterList(ParamLists[Idx], 0, TPC_ClassTemplateMember); 1363 } else if (ParamLists[Idx]->size() > 0) 1364 Diag(ParamLists[Idx]->getTemplateLoc(), 1365 diag::err_template_param_list_matches_nontemplate) 1366 << TemplateId 1367 << ParamLists[Idx]->getSourceRange(); 1368 else 1369 IsExplicitSpecialization = true; 1370 } 1371 1372 // If there were at least as many template-ids as there were template 1373 // parameter lists, then there are no template parameter lists remaining for 1374 // the declaration itself. 1375 if (Idx >= NumParamLists) 1376 return 0; 1377 1378 // If there were too many template parameter lists, complain about that now. 1379 if (Idx != NumParamLists - 1) { 1380 while (Idx < NumParamLists - 1) { 1381 bool isExplicitSpecHeader = ParamLists[Idx]->size() == 0; 1382 Diag(ParamLists[Idx]->getTemplateLoc(), 1383 isExplicitSpecHeader? diag::warn_template_spec_extra_headers 1384 : diag::err_template_spec_extra_headers) 1385 << SourceRange(ParamLists[Idx]->getTemplateLoc(), 1386 ParamLists[Idx]->getRAngleLoc()); 1387 1388 if (isExplicitSpecHeader && !ExplicitSpecializationsInSpecifier.empty()) { 1389 Diag(ExplicitSpecializationsInSpecifier.back()->getLocation(), 1390 diag::note_explicit_template_spec_does_not_need_header) 1391 << ExplicitSpecializationsInSpecifier.back(); 1392 ExplicitSpecializationsInSpecifier.pop_back(); 1393 } 1394 1395 ++Idx; 1396 } 1397 } 1398 1399 // Return the last template parameter list, which corresponds to the 1400 // entity being declared. 1401 return ParamLists[NumParamLists - 1]; 1402} 1403 1404QualType Sema::CheckTemplateIdType(TemplateName Name, 1405 SourceLocation TemplateLoc, 1406 const TemplateArgumentListInfo &TemplateArgs) { 1407 TemplateDecl *Template = Name.getAsTemplateDecl(); 1408 if (!Template) { 1409 // The template name does not resolve to a template, so we just 1410 // build a dependent template-id type. 1411 return Context.getTemplateSpecializationType(Name, TemplateArgs); 1412 } 1413 1414 // Check that the template argument list is well-formed for this 1415 // template. 1416 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(), 1417 TemplateArgs.size()); 1418 if (CheckTemplateArgumentList(Template, TemplateLoc, TemplateArgs, 1419 false, Converted)) 1420 return QualType(); 1421 1422 assert((Converted.structuredSize() == 1423 Template->getTemplateParameters()->size()) && 1424 "Converted template argument list is too short!"); 1425 1426 QualType CanonType; 1427 1428 if (Name.isDependent() || 1429 TemplateSpecializationType::anyDependentTemplateArguments( 1430 TemplateArgs)) { 1431 // This class template specialization is a dependent 1432 // type. Therefore, its canonical type is another class template 1433 // specialization type that contains all of the converted 1434 // arguments in canonical form. This ensures that, e.g., A<T> and 1435 // A<T, T> have identical types when A is declared as: 1436 // 1437 // template<typename T, typename U = T> struct A; 1438 TemplateName CanonName = Context.getCanonicalTemplateName(Name); 1439 CanonType = Context.getTemplateSpecializationType(CanonName, 1440 Converted.getFlatArguments(), 1441 Converted.flatSize()); 1442 1443 // FIXME: CanonType is not actually the canonical type, and unfortunately 1444 // it is a TemplateSpecializationType that we will never use again. 1445 // In the future, we need to teach getTemplateSpecializationType to only 1446 // build the canonical type and return that to us. 1447 CanonType = Context.getCanonicalType(CanonType); 1448 } else if (ClassTemplateDecl *ClassTemplate 1449 = dyn_cast<ClassTemplateDecl>(Template)) { 1450 // Find the class template specialization declaration that 1451 // corresponds to these arguments. 1452 llvm::FoldingSetNodeID ID; 1453 ClassTemplateSpecializationDecl::Profile(ID, 1454 Converted.getFlatArguments(), 1455 Converted.flatSize(), 1456 Context); 1457 void *InsertPos = 0; 1458 ClassTemplateSpecializationDecl *Decl 1459 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 1460 if (!Decl) { 1461 // This is the first time we have referenced this class template 1462 // specialization. Create the canonical declaration and add it to 1463 // the set of specializations. 1464 Decl = ClassTemplateSpecializationDecl::Create(Context, 1465 ClassTemplate->getDeclContext(), 1466 ClassTemplate->getLocation(), 1467 ClassTemplate, 1468 Converted, 0); 1469 ClassTemplate->getSpecializations().InsertNode(Decl, InsertPos); 1470 Decl->setLexicalDeclContext(CurContext); 1471 } 1472 1473 CanonType = Context.getTypeDeclType(Decl); 1474 assert(isa<RecordType>(CanonType) && 1475 "type of non-dependent specialization is not a RecordType"); 1476 } 1477 1478 // Build the fully-sugared type for this class template 1479 // specialization, which refers back to the class template 1480 // specialization we created or found. 1481 return Context.getTemplateSpecializationType(Name, TemplateArgs, CanonType); 1482} 1483 1484Action::TypeResult 1485Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc, 1486 SourceLocation LAngleLoc, 1487 ASTTemplateArgsPtr TemplateArgsIn, 1488 SourceLocation RAngleLoc) { 1489 TemplateName Template = TemplateD.getAsVal<TemplateName>(); 1490 1491 // Translate the parser's template argument list in our AST format. 1492 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 1493 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 1494 1495 QualType Result = CheckTemplateIdType(Template, TemplateLoc, TemplateArgs); 1496 TemplateArgsIn.release(); 1497 1498 if (Result.isNull()) 1499 return true; 1500 1501 TypeSourceInfo *DI = Context.CreateTypeSourceInfo(Result); 1502 TemplateSpecializationTypeLoc TL 1503 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc()); 1504 TL.setTemplateNameLoc(TemplateLoc); 1505 TL.setLAngleLoc(LAngleLoc); 1506 TL.setRAngleLoc(RAngleLoc); 1507 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) 1508 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); 1509 1510 return CreateLocInfoType(Result, DI).getAsOpaquePtr(); 1511} 1512 1513Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult, 1514 TagUseKind TUK, 1515 DeclSpec::TST TagSpec, 1516 SourceLocation TagLoc) { 1517 if (TypeResult.isInvalid()) 1518 return Sema::TypeResult(); 1519 1520 // FIXME: preserve source info, ideally without copying the DI. 1521 TypeSourceInfo *DI; 1522 QualType Type = GetTypeFromParser(TypeResult.get(), &DI); 1523 1524 // Verify the tag specifier. 1525 TagDecl::TagKind TagKind = TagDecl::getTagKindForTypeSpec(TagSpec); 1526 1527 if (const RecordType *RT = Type->getAs<RecordType>()) { 1528 RecordDecl *D = RT->getDecl(); 1529 1530 IdentifierInfo *Id = D->getIdentifier(); 1531 assert(Id && "templated class must have an identifier"); 1532 1533 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) { 1534 Diag(TagLoc, diag::err_use_with_wrong_tag) 1535 << Type 1536 << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName()); 1537 Diag(D->getLocation(), diag::note_previous_use); 1538 } 1539 } 1540 1541 QualType ElabType = Context.getElaboratedType(Type, TagKind); 1542 1543 return ElabType.getAsOpaquePtr(); 1544} 1545 1546Sema::OwningExprResult Sema::BuildTemplateIdExpr(const CXXScopeSpec &SS, 1547 LookupResult &R, 1548 bool RequiresADL, 1549 const TemplateArgumentListInfo &TemplateArgs) { 1550 // FIXME: Can we do any checking at this point? I guess we could check the 1551 // template arguments that we have against the template name, if the template 1552 // name refers to a single template. That's not a terribly common case, 1553 // though. 1554 1555 // These should be filtered out by our callers. 1556 assert(!R.empty() && "empty lookup results when building templateid"); 1557 assert(!R.isAmbiguous() && "ambiguous lookup when building templateid"); 1558 1559 NestedNameSpecifier *Qualifier = 0; 1560 SourceRange QualifierRange; 1561 if (SS.isSet()) { 1562 Qualifier = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 1563 QualifierRange = SS.getRange(); 1564 } 1565 1566 // We don't want lookup warnings at this point. 1567 R.suppressDiagnostics(); 1568 1569 bool Dependent 1570 = UnresolvedLookupExpr::ComputeDependence(R.begin(), R.end(), 1571 &TemplateArgs); 1572 UnresolvedLookupExpr *ULE 1573 = UnresolvedLookupExpr::Create(Context, Dependent, R.getNamingClass(), 1574 Qualifier, QualifierRange, 1575 R.getLookupName(), R.getNameLoc(), 1576 RequiresADL, TemplateArgs); 1577 ULE->addDecls(R.begin(), R.end()); 1578 1579 return Owned(ULE); 1580} 1581 1582// We actually only call this from template instantiation. 1583Sema::OwningExprResult 1584Sema::BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS, 1585 DeclarationName Name, 1586 SourceLocation NameLoc, 1587 const TemplateArgumentListInfo &TemplateArgs) { 1588 DeclContext *DC; 1589 if (!(DC = computeDeclContext(SS, false)) || 1590 DC->isDependentContext() || 1591 RequireCompleteDeclContext(SS)) 1592 return BuildDependentDeclRefExpr(SS, Name, NameLoc, &TemplateArgs); 1593 1594 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName); 1595 LookupTemplateName(R, (Scope*) 0, SS, QualType(), /*Entering*/ false); 1596 1597 if (R.isAmbiguous()) 1598 return ExprError(); 1599 1600 if (R.empty()) { 1601 Diag(NameLoc, diag::err_template_kw_refers_to_non_template) 1602 << Name << SS.getRange(); 1603 return ExprError(); 1604 } 1605 1606 if (ClassTemplateDecl *Temp = R.getAsSingle<ClassTemplateDecl>()) { 1607 Diag(NameLoc, diag::err_template_kw_refers_to_class_template) 1608 << (NestedNameSpecifier*) SS.getScopeRep() << Name << SS.getRange(); 1609 Diag(Temp->getLocation(), diag::note_referenced_class_template); 1610 return ExprError(); 1611 } 1612 1613 return BuildTemplateIdExpr(SS, R, /* ADL */ false, TemplateArgs); 1614} 1615 1616/// \brief Form a dependent template name. 1617/// 1618/// This action forms a dependent template name given the template 1619/// name and its (presumably dependent) scope specifier. For 1620/// example, given "MetaFun::template apply", the scope specifier \p 1621/// SS will be "MetaFun::", \p TemplateKWLoc contains the location 1622/// of the "template" keyword, and "apply" is the \p Name. 1623Sema::TemplateTy 1624Sema::ActOnDependentTemplateName(SourceLocation TemplateKWLoc, 1625 CXXScopeSpec &SS, 1626 UnqualifiedId &Name, 1627 TypeTy *ObjectType, 1628 bool EnteringContext) { 1629 DeclContext *LookupCtx = 0; 1630 if (SS.isSet()) 1631 LookupCtx = computeDeclContext(SS, EnteringContext); 1632 if (!LookupCtx && ObjectType) 1633 LookupCtx = computeDeclContext(QualType::getFromOpaquePtr(ObjectType)); 1634 if (LookupCtx) { 1635 // C++0x [temp.names]p5: 1636 // If a name prefixed by the keyword template is not the name of 1637 // a template, the program is ill-formed. [Note: the keyword 1638 // template may not be applied to non-template members of class 1639 // templates. -end note ] [ Note: as is the case with the 1640 // typename prefix, the template prefix is allowed in cases 1641 // where it is not strictly necessary; i.e., when the 1642 // nested-name-specifier or the expression on the left of the -> 1643 // or . is not dependent on a template-parameter, or the use 1644 // does not appear in the scope of a template. -end note] 1645 // 1646 // Note: C++03 was more strict here, because it banned the use of 1647 // the "template" keyword prior to a template-name that was not a 1648 // dependent name. C++ DR468 relaxed this requirement (the 1649 // "template" keyword is now permitted). We follow the C++0x 1650 // rules, even in C++03 mode, retroactively applying the DR. 1651 TemplateTy Template; 1652 TemplateNameKind TNK = isTemplateName(0, SS, Name, ObjectType, 1653 EnteringContext, Template); 1654 if (TNK == TNK_Non_template && LookupCtx->isDependentContext() && 1655 isa<CXXRecordDecl>(LookupCtx) && 1656 cast<CXXRecordDecl>(LookupCtx)->hasAnyDependentBases()) { 1657 // This is a dependent template. 1658 } else if (TNK == TNK_Non_template) { 1659 Diag(Name.getSourceRange().getBegin(), 1660 diag::err_template_kw_refers_to_non_template) 1661 << GetNameFromUnqualifiedId(Name) 1662 << Name.getSourceRange(); 1663 return TemplateTy(); 1664 } else { 1665 // We found something; return it. 1666 return Template; 1667 } 1668 } 1669 1670 NestedNameSpecifier *Qualifier 1671 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1672 1673 switch (Name.getKind()) { 1674 case UnqualifiedId::IK_Identifier: 1675 return TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1676 Name.Identifier)); 1677 1678 case UnqualifiedId::IK_OperatorFunctionId: 1679 return TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1680 Name.OperatorFunctionId.Operator)); 1681 1682 case UnqualifiedId::IK_LiteralOperatorId: 1683 assert(false && "We don't support these; Parse shouldn't have allowed propagation"); 1684 1685 default: 1686 break; 1687 } 1688 1689 Diag(Name.getSourceRange().getBegin(), 1690 diag::err_template_kw_refers_to_non_template) 1691 << GetNameFromUnqualifiedId(Name) 1692 << Name.getSourceRange(); 1693 return TemplateTy(); 1694} 1695 1696bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, 1697 const TemplateArgumentLoc &AL, 1698 TemplateArgumentListBuilder &Converted) { 1699 const TemplateArgument &Arg = AL.getArgument(); 1700 1701 // Check template type parameter. 1702 switch(Arg.getKind()) { 1703 case TemplateArgument::Type: 1704 // C++ [temp.arg.type]p1: 1705 // A template-argument for a template-parameter which is a 1706 // type shall be a type-id. 1707 break; 1708 case TemplateArgument::Template: { 1709 // We have a template type parameter but the template argument 1710 // is a template without any arguments. 1711 SourceRange SR = AL.getSourceRange(); 1712 TemplateName Name = Arg.getAsTemplate(); 1713 Diag(SR.getBegin(), diag::err_template_missing_args) 1714 << Name << SR; 1715 if (TemplateDecl *Decl = Name.getAsTemplateDecl()) 1716 Diag(Decl->getLocation(), diag::note_template_decl_here); 1717 1718 return true; 1719 } 1720 default: { 1721 // We have a template type parameter but the template argument 1722 // is not a type. 1723 SourceRange SR = AL.getSourceRange(); 1724 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; 1725 Diag(Param->getLocation(), diag::note_template_param_here); 1726 1727 return true; 1728 } 1729 } 1730 1731 if (CheckTemplateArgument(Param, AL.getTypeSourceInfo())) 1732 return true; 1733 1734 // Add the converted template type argument. 1735 Converted.Append( 1736 TemplateArgument(Context.getCanonicalType(Arg.getAsType()))); 1737 return false; 1738} 1739 1740/// \brief Substitute template arguments into the default template argument for 1741/// the given template type parameter. 1742/// 1743/// \param SemaRef the semantic analysis object for which we are performing 1744/// the substitution. 1745/// 1746/// \param Template the template that we are synthesizing template arguments 1747/// for. 1748/// 1749/// \param TemplateLoc the location of the template name that started the 1750/// template-id we are checking. 1751/// 1752/// \param RAngleLoc the location of the right angle bracket ('>') that 1753/// terminates the template-id. 1754/// 1755/// \param Param the template template parameter whose default we are 1756/// substituting into. 1757/// 1758/// \param Converted the list of template arguments provided for template 1759/// parameters that precede \p Param in the template parameter list. 1760/// 1761/// \returns the substituted template argument, or NULL if an error occurred. 1762static TypeSourceInfo * 1763SubstDefaultTemplateArgument(Sema &SemaRef, 1764 TemplateDecl *Template, 1765 SourceLocation TemplateLoc, 1766 SourceLocation RAngleLoc, 1767 TemplateTypeParmDecl *Param, 1768 TemplateArgumentListBuilder &Converted) { 1769 TypeSourceInfo *ArgType = Param->getDefaultArgumentInfo(); 1770 1771 // If the argument type is dependent, instantiate it now based 1772 // on the previously-computed template arguments. 1773 if (ArgType->getType()->isDependentType()) { 1774 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1775 /*TakeArgs=*/false); 1776 1777 MultiLevelTemplateArgumentList AllTemplateArgs 1778 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1779 1780 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1781 Template, Converted.getFlatArguments(), 1782 Converted.flatSize(), 1783 SourceRange(TemplateLoc, RAngleLoc)); 1784 1785 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, 1786 Param->getDefaultArgumentLoc(), 1787 Param->getDeclName()); 1788 } 1789 1790 return ArgType; 1791} 1792 1793/// \brief Substitute template arguments into the default template argument for 1794/// the given non-type template parameter. 1795/// 1796/// \param SemaRef the semantic analysis object for which we are performing 1797/// the substitution. 1798/// 1799/// \param Template the template that we are synthesizing template arguments 1800/// for. 1801/// 1802/// \param TemplateLoc the location of the template name that started the 1803/// template-id we are checking. 1804/// 1805/// \param RAngleLoc the location of the right angle bracket ('>') that 1806/// terminates the template-id. 1807/// 1808/// \param Param the non-type template parameter whose default we are 1809/// substituting into. 1810/// 1811/// \param Converted the list of template arguments provided for template 1812/// parameters that precede \p Param in the template parameter list. 1813/// 1814/// \returns the substituted template argument, or NULL if an error occurred. 1815static Sema::OwningExprResult 1816SubstDefaultTemplateArgument(Sema &SemaRef, 1817 TemplateDecl *Template, 1818 SourceLocation TemplateLoc, 1819 SourceLocation RAngleLoc, 1820 NonTypeTemplateParmDecl *Param, 1821 TemplateArgumentListBuilder &Converted) { 1822 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1823 /*TakeArgs=*/false); 1824 1825 MultiLevelTemplateArgumentList AllTemplateArgs 1826 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1827 1828 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1829 Template, Converted.getFlatArguments(), 1830 Converted.flatSize(), 1831 SourceRange(TemplateLoc, RAngleLoc)); 1832 1833 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); 1834} 1835 1836/// \brief Substitute template arguments into the default template argument for 1837/// the given template template parameter. 1838/// 1839/// \param SemaRef the semantic analysis object for which we are performing 1840/// the substitution. 1841/// 1842/// \param Template the template that we are synthesizing template arguments 1843/// for. 1844/// 1845/// \param TemplateLoc the location of the template name that started the 1846/// template-id we are checking. 1847/// 1848/// \param RAngleLoc the location of the right angle bracket ('>') that 1849/// terminates the template-id. 1850/// 1851/// \param Param the template template parameter whose default we are 1852/// substituting into. 1853/// 1854/// \param Converted the list of template arguments provided for template 1855/// parameters that precede \p Param in the template parameter list. 1856/// 1857/// \returns the substituted template argument, or NULL if an error occurred. 1858static TemplateName 1859SubstDefaultTemplateArgument(Sema &SemaRef, 1860 TemplateDecl *Template, 1861 SourceLocation TemplateLoc, 1862 SourceLocation RAngleLoc, 1863 TemplateTemplateParmDecl *Param, 1864 TemplateArgumentListBuilder &Converted) { 1865 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1866 /*TakeArgs=*/false); 1867 1868 MultiLevelTemplateArgumentList AllTemplateArgs 1869 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1870 1871 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1872 Template, Converted.getFlatArguments(), 1873 Converted.flatSize(), 1874 SourceRange(TemplateLoc, RAngleLoc)); 1875 1876 return SemaRef.SubstTemplateName( 1877 Param->getDefaultArgument().getArgument().getAsTemplate(), 1878 Param->getDefaultArgument().getTemplateNameLoc(), 1879 AllTemplateArgs); 1880} 1881 1882/// \brief If the given template parameter has a default template 1883/// argument, substitute into that default template argument and 1884/// return the corresponding template argument. 1885TemplateArgumentLoc 1886Sema::SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template, 1887 SourceLocation TemplateLoc, 1888 SourceLocation RAngleLoc, 1889 Decl *Param, 1890 TemplateArgumentListBuilder &Converted) { 1891 if (TemplateTypeParmDecl *TypeParm = dyn_cast<TemplateTypeParmDecl>(Param)) { 1892 if (!TypeParm->hasDefaultArgument()) 1893 return TemplateArgumentLoc(); 1894 1895 TypeSourceInfo *DI = SubstDefaultTemplateArgument(*this, Template, 1896 TemplateLoc, 1897 RAngleLoc, 1898 TypeParm, 1899 Converted); 1900 if (DI) 1901 return TemplateArgumentLoc(TemplateArgument(DI->getType()), DI); 1902 1903 return TemplateArgumentLoc(); 1904 } 1905 1906 if (NonTypeTemplateParmDecl *NonTypeParm 1907 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1908 if (!NonTypeParm->hasDefaultArgument()) 1909 return TemplateArgumentLoc(); 1910 1911 OwningExprResult Arg = SubstDefaultTemplateArgument(*this, Template, 1912 TemplateLoc, 1913 RAngleLoc, 1914 NonTypeParm, 1915 Converted); 1916 if (Arg.isInvalid()) 1917 return TemplateArgumentLoc(); 1918 1919 Expr *ArgE = Arg.takeAs<Expr>(); 1920 return TemplateArgumentLoc(TemplateArgument(ArgE), ArgE); 1921 } 1922 1923 TemplateTemplateParmDecl *TempTempParm 1924 = cast<TemplateTemplateParmDecl>(Param); 1925 if (!TempTempParm->hasDefaultArgument()) 1926 return TemplateArgumentLoc(); 1927 1928 TemplateName TName = SubstDefaultTemplateArgument(*this, Template, 1929 TemplateLoc, 1930 RAngleLoc, 1931 TempTempParm, 1932 Converted); 1933 if (TName.isNull()) 1934 return TemplateArgumentLoc(); 1935 1936 return TemplateArgumentLoc(TemplateArgument(TName), 1937 TempTempParm->getDefaultArgument().getTemplateQualifierRange(), 1938 TempTempParm->getDefaultArgument().getTemplateNameLoc()); 1939} 1940 1941/// \brief Check that the given template argument corresponds to the given 1942/// template parameter. 1943bool Sema::CheckTemplateArgument(NamedDecl *Param, 1944 const TemplateArgumentLoc &Arg, 1945 TemplateDecl *Template, 1946 SourceLocation TemplateLoc, 1947 SourceLocation RAngleLoc, 1948 TemplateArgumentListBuilder &Converted, 1949 CheckTemplateArgumentKind CTAK) { 1950 // Check template type parameters. 1951 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) 1952 return CheckTemplateTypeArgument(TTP, Arg, Converted); 1953 1954 // Check non-type template parameters. 1955 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1956 // Do substitution on the type of the non-type template parameter 1957 // with the template arguments we've seen thus far. 1958 QualType NTTPType = NTTP->getType(); 1959 if (NTTPType->isDependentType()) { 1960 // Do substitution on the type of the non-type template parameter. 1961 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 1962 NTTP, Converted.getFlatArguments(), 1963 Converted.flatSize(), 1964 SourceRange(TemplateLoc, RAngleLoc)); 1965 1966 TemplateArgumentList TemplateArgs(Context, Converted, 1967 /*TakeArgs=*/false); 1968 NTTPType = SubstType(NTTPType, 1969 MultiLevelTemplateArgumentList(TemplateArgs), 1970 NTTP->getLocation(), 1971 NTTP->getDeclName()); 1972 // If that worked, check the non-type template parameter type 1973 // for validity. 1974 if (!NTTPType.isNull()) 1975 NTTPType = CheckNonTypeTemplateParameterType(NTTPType, 1976 NTTP->getLocation()); 1977 if (NTTPType.isNull()) 1978 return true; 1979 } 1980 1981 switch (Arg.getArgument().getKind()) { 1982 case TemplateArgument::Null: 1983 assert(false && "Should never see a NULL template argument here"); 1984 return true; 1985 1986 case TemplateArgument::Expression: { 1987 Expr *E = Arg.getArgument().getAsExpr(); 1988 TemplateArgument Result; 1989 if (CheckTemplateArgument(NTTP, NTTPType, E, Result, CTAK)) 1990 return true; 1991 1992 Converted.Append(Result); 1993 break; 1994 } 1995 1996 case TemplateArgument::Declaration: 1997 case TemplateArgument::Integral: 1998 // We've already checked this template argument, so just copy 1999 // it to the list of converted arguments. 2000 Converted.Append(Arg.getArgument()); 2001 break; 2002 2003 case TemplateArgument::Template: 2004 // We were given a template template argument. It may not be ill-formed; 2005 // see below. 2006 if (DependentTemplateName *DTN 2007 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) { 2008 // We have a template argument such as \c T::template X, which we 2009 // parsed as a template template argument. However, since we now 2010 // know that we need a non-type template argument, convert this 2011 // template name into an expression. 2012 Expr *E = DependentScopeDeclRefExpr::Create(Context, 2013 DTN->getQualifier(), 2014 Arg.getTemplateQualifierRange(), 2015 DTN->getIdentifier(), 2016 Arg.getTemplateNameLoc()); 2017 2018 TemplateArgument Result; 2019 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 2020 return true; 2021 2022 Converted.Append(Result); 2023 break; 2024 } 2025 2026 // We have a template argument that actually does refer to a class 2027 // template, template alias, or template template parameter, and 2028 // therefore cannot be a non-type template argument. 2029 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) 2030 << Arg.getSourceRange(); 2031 2032 Diag(Param->getLocation(), diag::note_template_param_here); 2033 return true; 2034 2035 case TemplateArgument::Type: { 2036 // We have a non-type template parameter but the template 2037 // argument is a type. 2038 2039 // C++ [temp.arg]p2: 2040 // In a template-argument, an ambiguity between a type-id and 2041 // an expression is resolved to a type-id, regardless of the 2042 // form of the corresponding template-parameter. 2043 // 2044 // We warn specifically about this case, since it can be rather 2045 // confusing for users. 2046 QualType T = Arg.getArgument().getAsType(); 2047 SourceRange SR = Arg.getSourceRange(); 2048 if (T->isFunctionType()) 2049 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; 2050 else 2051 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; 2052 Diag(Param->getLocation(), diag::note_template_param_here); 2053 return true; 2054 } 2055 2056 case TemplateArgument::Pack: 2057 llvm_unreachable("Caller must expand template argument packs"); 2058 break; 2059 } 2060 2061 return false; 2062 } 2063 2064 2065 // Check template template parameters. 2066 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); 2067 2068 // Substitute into the template parameter list of the template 2069 // template parameter, since previously-supplied template arguments 2070 // may appear within the template template parameter. 2071 { 2072 // Set up a template instantiation context. 2073 LocalInstantiationScope Scope(*this); 2074 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 2075 TempParm, Converted.getFlatArguments(), 2076 Converted.flatSize(), 2077 SourceRange(TemplateLoc, RAngleLoc)); 2078 2079 TemplateArgumentList TemplateArgs(Context, Converted, 2080 /*TakeArgs=*/false); 2081 TempParm = cast_or_null<TemplateTemplateParmDecl>( 2082 SubstDecl(TempParm, CurContext, 2083 MultiLevelTemplateArgumentList(TemplateArgs))); 2084 if (!TempParm) 2085 return true; 2086 2087 // FIXME: TempParam is leaked. 2088 } 2089 2090 switch (Arg.getArgument().getKind()) { 2091 case TemplateArgument::Null: 2092 assert(false && "Should never see a NULL template argument here"); 2093 return true; 2094 2095 case TemplateArgument::Template: 2096 if (CheckTemplateArgument(TempParm, Arg)) 2097 return true; 2098 2099 Converted.Append(Arg.getArgument()); 2100 break; 2101 2102 case TemplateArgument::Expression: 2103 case TemplateArgument::Type: 2104 // We have a template template parameter but the template 2105 // argument does not refer to a template. 2106 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template); 2107 return true; 2108 2109 case TemplateArgument::Declaration: 2110 llvm_unreachable( 2111 "Declaration argument with template template parameter"); 2112 break; 2113 case TemplateArgument::Integral: 2114 llvm_unreachable( 2115 "Integral argument with template template parameter"); 2116 break; 2117 2118 case TemplateArgument::Pack: 2119 llvm_unreachable("Caller must expand template argument packs"); 2120 break; 2121 } 2122 2123 return false; 2124} 2125 2126/// \brief Check that the given template argument list is well-formed 2127/// for specializing the given template. 2128bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, 2129 SourceLocation TemplateLoc, 2130 const TemplateArgumentListInfo &TemplateArgs, 2131 bool PartialTemplateArgs, 2132 TemplateArgumentListBuilder &Converted) { 2133 TemplateParameterList *Params = Template->getTemplateParameters(); 2134 unsigned NumParams = Params->size(); 2135 unsigned NumArgs = TemplateArgs.size(); 2136 bool Invalid = false; 2137 2138 SourceLocation RAngleLoc = TemplateArgs.getRAngleLoc(); 2139 2140 bool HasParameterPack = 2141 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); 2142 2143 if ((NumArgs > NumParams && !HasParameterPack) || 2144 (NumArgs < Params->getMinRequiredArguments() && 2145 !PartialTemplateArgs)) { 2146 // FIXME: point at either the first arg beyond what we can handle, 2147 // or the '>', depending on whether we have too many or too few 2148 // arguments. 2149 SourceRange Range; 2150 if (NumArgs > NumParams) 2151 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc); 2152 Diag(TemplateLoc, diag::err_template_arg_list_different_arity) 2153 << (NumArgs > NumParams) 2154 << (isa<ClassTemplateDecl>(Template)? 0 : 2155 isa<FunctionTemplateDecl>(Template)? 1 : 2156 isa<TemplateTemplateParmDecl>(Template)? 2 : 3) 2157 << Template << Range; 2158 Diag(Template->getLocation(), diag::note_template_decl_here) 2159 << Params->getSourceRange(); 2160 Invalid = true; 2161 } 2162 2163 // C++ [temp.arg]p1: 2164 // [...] The type and form of each template-argument specified in 2165 // a template-id shall match the type and form specified for the 2166 // corresponding parameter declared by the template in its 2167 // template-parameter-list. 2168 unsigned ArgIdx = 0; 2169 for (TemplateParameterList::iterator Param = Params->begin(), 2170 ParamEnd = Params->end(); 2171 Param != ParamEnd; ++Param, ++ArgIdx) { 2172 if (ArgIdx > NumArgs && PartialTemplateArgs) 2173 break; 2174 2175 // If we have a template parameter pack, check every remaining template 2176 // argument against that template parameter pack. 2177 if ((*Param)->isTemplateParameterPack()) { 2178 Converted.BeginPack(); 2179 for (; ArgIdx < NumArgs; ++ArgIdx) { 2180 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2181 TemplateLoc, RAngleLoc, Converted)) { 2182 Invalid = true; 2183 break; 2184 } 2185 } 2186 Converted.EndPack(); 2187 continue; 2188 } 2189 2190 if (ArgIdx < NumArgs) { 2191 // Check the template argument we were given. 2192 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 2193 TemplateLoc, RAngleLoc, Converted)) 2194 return true; 2195 2196 continue; 2197 } 2198 2199 // We have a default template argument that we will use. 2200 TemplateArgumentLoc Arg; 2201 2202 // Retrieve the default template argument from the template 2203 // parameter. For each kind of template parameter, we substitute the 2204 // template arguments provided thus far and any "outer" template arguments 2205 // (when the template parameter was part of a nested template) into 2206 // the default argument. 2207 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { 2208 if (!TTP->hasDefaultArgument()) { 2209 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2210 break; 2211 } 2212 2213 TypeSourceInfo *ArgType = SubstDefaultTemplateArgument(*this, 2214 Template, 2215 TemplateLoc, 2216 RAngleLoc, 2217 TTP, 2218 Converted); 2219 if (!ArgType) 2220 return true; 2221 2222 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), 2223 ArgType); 2224 } else if (NonTypeTemplateParmDecl *NTTP 2225 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { 2226 if (!NTTP->hasDefaultArgument()) { 2227 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2228 break; 2229 } 2230 2231 Sema::OwningExprResult E = SubstDefaultTemplateArgument(*this, Template, 2232 TemplateLoc, 2233 RAngleLoc, 2234 NTTP, 2235 Converted); 2236 if (E.isInvalid()) 2237 return true; 2238 2239 Expr *Ex = E.takeAs<Expr>(); 2240 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); 2241 } else { 2242 TemplateTemplateParmDecl *TempParm 2243 = cast<TemplateTemplateParmDecl>(*Param); 2244 2245 if (!TempParm->hasDefaultArgument()) { 2246 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 2247 break; 2248 } 2249 2250 TemplateName Name = SubstDefaultTemplateArgument(*this, Template, 2251 TemplateLoc, 2252 RAngleLoc, 2253 TempParm, 2254 Converted); 2255 if (Name.isNull()) 2256 return true; 2257 2258 Arg = TemplateArgumentLoc(TemplateArgument(Name), 2259 TempParm->getDefaultArgument().getTemplateQualifierRange(), 2260 TempParm->getDefaultArgument().getTemplateNameLoc()); 2261 } 2262 2263 // Introduce an instantiation record that describes where we are using 2264 // the default template argument. 2265 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, 2266 Converted.getFlatArguments(), 2267 Converted.flatSize(), 2268 SourceRange(TemplateLoc, RAngleLoc)); 2269 2270 // Check the default template argument. 2271 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, 2272 RAngleLoc, Converted)) 2273 return true; 2274 } 2275 2276 return Invalid; 2277} 2278 2279/// \brief Check a template argument against its corresponding 2280/// template type parameter. 2281/// 2282/// This routine implements the semantics of C++ [temp.arg.type]. It 2283/// returns true if an error occurred, and false otherwise. 2284bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, 2285 TypeSourceInfo *ArgInfo) { 2286 assert(ArgInfo && "invalid TypeSourceInfo"); 2287 QualType Arg = ArgInfo->getType(); 2288 2289 // C++ [temp.arg.type]p2: 2290 // A local type, a type with no linkage, an unnamed type or a type 2291 // compounded from any of these types shall not be used as a 2292 // template-argument for a template type-parameter. 2293 // 2294 // FIXME: Perform the recursive and no-linkage type checks. 2295 const TagType *Tag = 0; 2296 if (const EnumType *EnumT = Arg->getAs<EnumType>()) 2297 Tag = EnumT; 2298 else if (const RecordType *RecordT = Arg->getAs<RecordType>()) 2299 Tag = RecordT; 2300 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) { 2301 SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange(); 2302 return Diag(SR.getBegin(), diag::err_template_arg_local_type) 2303 << QualType(Tag, 0) << SR; 2304 } else if (Tag && !Tag->getDecl()->getDeclName() && 2305 !Tag->getDecl()->getTypedefForAnonDecl()) { 2306 SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange(); 2307 Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR; 2308 Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here); 2309 return true; 2310 } else if (Context.hasSameUnqualifiedType(Arg, Context.OverloadTy)) { 2311 SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange(); 2312 return Diag(SR.getBegin(), diag::err_template_arg_overload_type) << SR; 2313 } 2314 2315 return false; 2316} 2317 2318/// \brief Checks whether the given template argument is the address 2319/// of an object or function according to C++ [temp.arg.nontype]p1. 2320static bool 2321CheckTemplateArgumentAddressOfObjectOrFunction(Sema &S, 2322 NonTypeTemplateParmDecl *Param, 2323 QualType ParamType, 2324 Expr *ArgIn, 2325 TemplateArgument &Converted) { 2326 bool Invalid = false; 2327 Expr *Arg = ArgIn; 2328 QualType ArgType = Arg->getType(); 2329 2330 // See through any implicit casts we added to fix the type. 2331 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2332 Arg = Cast->getSubExpr(); 2333 2334 // C++ [temp.arg.nontype]p1: 2335 // 2336 // A template-argument for a non-type, non-template 2337 // template-parameter shall be one of: [...] 2338 // 2339 // -- the address of an object or function with external 2340 // linkage, including function templates and function 2341 // template-ids but excluding non-static class members, 2342 // expressed as & id-expression where the & is optional if 2343 // the name refers to a function or array, or if the 2344 // corresponding template-parameter is a reference; or 2345 DeclRefExpr *DRE = 0; 2346 2347 // Ignore (and complain about) any excess parentheses. 2348 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2349 if (!Invalid) { 2350 S.Diag(Arg->getSourceRange().getBegin(), 2351 diag::err_template_arg_extra_parens) 2352 << Arg->getSourceRange(); 2353 Invalid = true; 2354 } 2355 2356 Arg = Parens->getSubExpr(); 2357 } 2358 2359 bool AddressTaken = false; 2360 SourceLocation AddrOpLoc; 2361 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2362 if (UnOp->getOpcode() == UnaryOperator::AddrOf) { 2363 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2364 AddressTaken = true; 2365 AddrOpLoc = UnOp->getOperatorLoc(); 2366 } 2367 } else 2368 DRE = dyn_cast<DeclRefExpr>(Arg); 2369 2370 if (!DRE) { 2371 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_decl_ref) 2372 << Arg->getSourceRange(); 2373 S.Diag(Param->getLocation(), diag::note_template_param_here); 2374 return true; 2375 } 2376 2377 // Stop checking the precise nature of the argument if it is value dependent, 2378 // it should be checked when instantiated. 2379 if (Arg->isValueDependent()) { 2380 Converted = TemplateArgument(ArgIn->Retain()); 2381 return false; 2382 } 2383 2384 if (!isa<ValueDecl>(DRE->getDecl())) { 2385 S.Diag(Arg->getSourceRange().getBegin(), 2386 diag::err_template_arg_not_object_or_func_form) 2387 << Arg->getSourceRange(); 2388 S.Diag(Param->getLocation(), diag::note_template_param_here); 2389 return true; 2390 } 2391 2392 NamedDecl *Entity = 0; 2393 2394 // Cannot refer to non-static data members 2395 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) { 2396 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field) 2397 << Field << Arg->getSourceRange(); 2398 S.Diag(Param->getLocation(), diag::note_template_param_here); 2399 return true; 2400 } 2401 2402 // Cannot refer to non-static member functions 2403 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl())) 2404 if (!Method->isStatic()) { 2405 S.Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_method) 2406 << Method << Arg->getSourceRange(); 2407 S.Diag(Param->getLocation(), diag::note_template_param_here); 2408 return true; 2409 } 2410 2411 // Functions must have external linkage. 2412 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) { 2413 if (!isExternalLinkage(Func->getLinkage())) { 2414 S.Diag(Arg->getSourceRange().getBegin(), 2415 diag::err_template_arg_function_not_extern) 2416 << Func << Arg->getSourceRange(); 2417 S.Diag(Func->getLocation(), diag::note_template_arg_internal_object) 2418 << true; 2419 return true; 2420 } 2421 2422 // Okay: we've named a function with external linkage. 2423 Entity = Func; 2424 2425 // If the template parameter has pointer type, the function decays. 2426 if (ParamType->isPointerType() && !AddressTaken) 2427 ArgType = S.Context.getPointerType(Func->getType()); 2428 else if (AddressTaken && ParamType->isReferenceType()) { 2429 // If we originally had an address-of operator, but the 2430 // parameter has reference type, complain and (if things look 2431 // like they will work) drop the address-of operator. 2432 if (!S.Context.hasSameUnqualifiedType(Func->getType(), 2433 ParamType.getNonReferenceType())) { 2434 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2435 << ParamType; 2436 S.Diag(Param->getLocation(), diag::note_template_param_here); 2437 return true; 2438 } 2439 2440 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2441 << ParamType 2442 << FixItHint::CreateRemoval(AddrOpLoc); 2443 S.Diag(Param->getLocation(), diag::note_template_param_here); 2444 2445 ArgType = Func->getType(); 2446 } 2447 } else if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 2448 if (!isExternalLinkage(Var->getLinkage())) { 2449 S.Diag(Arg->getSourceRange().getBegin(), 2450 diag::err_template_arg_object_not_extern) 2451 << Var << Arg->getSourceRange(); 2452 S.Diag(Var->getLocation(), diag::note_template_arg_internal_object) 2453 << true; 2454 return true; 2455 } 2456 2457 // A value of reference type is not an object. 2458 if (Var->getType()->isReferenceType()) { 2459 S.Diag(Arg->getSourceRange().getBegin(), 2460 diag::err_template_arg_reference_var) 2461 << Var->getType() << Arg->getSourceRange(); 2462 S.Diag(Param->getLocation(), diag::note_template_param_here); 2463 return true; 2464 } 2465 2466 // Okay: we've named an object with external linkage 2467 Entity = Var; 2468 2469 // If the template parameter has pointer type, we must have taken 2470 // the address of this object. 2471 if (ParamType->isReferenceType()) { 2472 if (AddressTaken) { 2473 // If we originally had an address-of operator, but the 2474 // parameter has reference type, complain and (if things look 2475 // like they will work) drop the address-of operator. 2476 if (!S.Context.hasSameUnqualifiedType(Var->getType(), 2477 ParamType.getNonReferenceType())) { 2478 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2479 << ParamType; 2480 S.Diag(Param->getLocation(), diag::note_template_param_here); 2481 return true; 2482 } 2483 2484 S.Diag(AddrOpLoc, diag::err_template_arg_address_of_non_pointer) 2485 << ParamType 2486 << FixItHint::CreateRemoval(AddrOpLoc); 2487 S.Diag(Param->getLocation(), diag::note_template_param_here); 2488 2489 ArgType = Var->getType(); 2490 } 2491 } else if (!AddressTaken && ParamType->isPointerType()) { 2492 if (Var->getType()->isArrayType()) { 2493 // Array-to-pointer decay. 2494 ArgType = S.Context.getArrayDecayedType(Var->getType()); 2495 } else { 2496 // If the template parameter has pointer type but the address of 2497 // this object was not taken, complain and (possibly) recover by 2498 // taking the address of the entity. 2499 ArgType = S.Context.getPointerType(Var->getType()); 2500 if (!S.Context.hasSameUnqualifiedType(ArgType, ParamType)) { 2501 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2502 << ParamType; 2503 S.Diag(Param->getLocation(), diag::note_template_param_here); 2504 return true; 2505 } 2506 2507 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_address_of) 2508 << ParamType 2509 << FixItHint::CreateInsertion(Arg->getLocStart(), "&"); 2510 2511 S.Diag(Param->getLocation(), diag::note_template_param_here); 2512 } 2513 } 2514 } else { 2515 // We found something else, but we don't know specifically what it is. 2516 S.Diag(Arg->getSourceRange().getBegin(), 2517 diag::err_template_arg_not_object_or_func) 2518 << Arg->getSourceRange(); 2519 S.Diag(DRE->getDecl()->getLocation(), diag::note_template_arg_refers_here); 2520 return true; 2521 } 2522 2523 if (ParamType->isPointerType() && 2524 !ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType() && 2525 S.IsQualificationConversion(ArgType, ParamType)) { 2526 // For pointer-to-object types, qualification conversions are 2527 // permitted. 2528 } else { 2529 if (const ReferenceType *ParamRef = ParamType->getAs<ReferenceType>()) { 2530 if (!ParamRef->getPointeeType()->isFunctionType()) { 2531 // C++ [temp.arg.nontype]p5b3: 2532 // For a non-type template-parameter of type reference to 2533 // object, no conversions apply. The type referred to by the 2534 // reference may be more cv-qualified than the (otherwise 2535 // identical) type of the template- argument. The 2536 // template-parameter is bound directly to the 2537 // template-argument, which shall be an lvalue. 2538 2539 // FIXME: Other qualifiers? 2540 unsigned ParamQuals = ParamRef->getPointeeType().getCVRQualifiers(); 2541 unsigned ArgQuals = ArgType.getCVRQualifiers(); 2542 2543 if ((ParamQuals | ArgQuals) != ParamQuals) { 2544 S.Diag(Arg->getSourceRange().getBegin(), 2545 diag::err_template_arg_ref_bind_ignores_quals) 2546 << ParamType << Arg->getType() 2547 << Arg->getSourceRange(); 2548 S.Diag(Param->getLocation(), diag::note_template_param_here); 2549 return true; 2550 } 2551 } 2552 } 2553 2554 // At this point, the template argument refers to an object or 2555 // function with external linkage. We now need to check whether the 2556 // argument and parameter types are compatible. 2557 if (!S.Context.hasSameUnqualifiedType(ArgType, 2558 ParamType.getNonReferenceType())) { 2559 // We can't perform this conversion or binding. 2560 if (ParamType->isReferenceType()) 2561 S.Diag(Arg->getLocStart(), diag::err_template_arg_no_ref_bind) 2562 << ParamType << Arg->getType() << Arg->getSourceRange(); 2563 else 2564 S.Diag(Arg->getLocStart(), diag::err_template_arg_not_convertible) 2565 << Arg->getType() << ParamType << Arg->getSourceRange(); 2566 S.Diag(Param->getLocation(), diag::note_template_param_here); 2567 return true; 2568 } 2569 } 2570 2571 // Create the template argument. 2572 Converted = TemplateArgument(Entity->getCanonicalDecl()); 2573 return false; 2574} 2575 2576/// \brief Checks whether the given template argument is a pointer to 2577/// member constant according to C++ [temp.arg.nontype]p1. 2578bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, 2579 TemplateArgument &Converted) { 2580 bool Invalid = false; 2581 2582 // See through any implicit casts we added to fix the type. 2583 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2584 Arg = Cast->getSubExpr(); 2585 2586 // C++ [temp.arg.nontype]p1: 2587 // 2588 // A template-argument for a non-type, non-template 2589 // template-parameter shall be one of: [...] 2590 // 2591 // -- a pointer to member expressed as described in 5.3.1. 2592 DeclRefExpr *DRE = 0; 2593 2594 // Ignore (and complain about) any excess parentheses. 2595 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2596 if (!Invalid) { 2597 Diag(Arg->getSourceRange().getBegin(), 2598 diag::err_template_arg_extra_parens) 2599 << Arg->getSourceRange(); 2600 Invalid = true; 2601 } 2602 2603 Arg = Parens->getSubExpr(); 2604 } 2605 2606 // A pointer-to-member constant written &Class::member. 2607 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2608 if (UnOp->getOpcode() == UnaryOperator::AddrOf) { 2609 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2610 if (DRE && !DRE->getQualifier()) 2611 DRE = 0; 2612 } 2613 } 2614 // A constant of pointer-to-member type. 2615 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { 2616 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { 2617 if (VD->getType()->isMemberPointerType()) { 2618 if (isa<NonTypeTemplateParmDecl>(VD) || 2619 (isa<VarDecl>(VD) && 2620 Context.getCanonicalType(VD->getType()).isConstQualified())) { 2621 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2622 Converted = TemplateArgument(Arg->Retain()); 2623 else 2624 Converted = TemplateArgument(VD->getCanonicalDecl()); 2625 return Invalid; 2626 } 2627 } 2628 } 2629 2630 DRE = 0; 2631 } 2632 2633 if (!DRE) 2634 return Diag(Arg->getSourceRange().getBegin(), 2635 diag::err_template_arg_not_pointer_to_member_form) 2636 << Arg->getSourceRange(); 2637 2638 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { 2639 assert((isa<FieldDecl>(DRE->getDecl()) || 2640 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && 2641 "Only non-static member pointers can make it here"); 2642 2643 // Okay: this is the address of a non-static member, and therefore 2644 // a member pointer constant. 2645 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2646 Converted = TemplateArgument(Arg->Retain()); 2647 else 2648 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); 2649 return Invalid; 2650 } 2651 2652 // We found something else, but we don't know specifically what it is. 2653 Diag(Arg->getSourceRange().getBegin(), 2654 diag::err_template_arg_not_pointer_to_member_form) 2655 << Arg->getSourceRange(); 2656 Diag(DRE->getDecl()->getLocation(), 2657 diag::note_template_arg_refers_here); 2658 return true; 2659} 2660 2661/// \brief Check a template argument against its corresponding 2662/// non-type template parameter. 2663/// 2664/// This routine implements the semantics of C++ [temp.arg.nontype]. 2665/// It returns true if an error occurred, and false otherwise. \p 2666/// InstantiatedParamType is the type of the non-type template 2667/// parameter after it has been instantiated. 2668/// 2669/// If no error was detected, Converted receives the converted template argument. 2670bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, 2671 QualType InstantiatedParamType, Expr *&Arg, 2672 TemplateArgument &Converted, 2673 CheckTemplateArgumentKind CTAK) { 2674 SourceLocation StartLoc = Arg->getSourceRange().getBegin(); 2675 2676 // If either the parameter has a dependent type or the argument is 2677 // type-dependent, there's nothing we can check now. 2678 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { 2679 // FIXME: Produce a cloned, canonical expression? 2680 Converted = TemplateArgument(Arg); 2681 return false; 2682 } 2683 2684 // C++ [temp.arg.nontype]p5: 2685 // The following conversions are performed on each expression used 2686 // as a non-type template-argument. If a non-type 2687 // template-argument cannot be converted to the type of the 2688 // corresponding template-parameter then the program is 2689 // ill-formed. 2690 // 2691 // -- for a non-type template-parameter of integral or 2692 // enumeration type, integral promotions (4.5) and integral 2693 // conversions (4.7) are applied. 2694 QualType ParamType = InstantiatedParamType; 2695 QualType ArgType = Arg->getType(); 2696 if (ParamType->isIntegralType() || ParamType->isEnumeralType()) { 2697 // C++ [temp.arg.nontype]p1: 2698 // A template-argument for a non-type, non-template 2699 // template-parameter shall be one of: 2700 // 2701 // -- an integral constant-expression of integral or enumeration 2702 // type; or 2703 // -- the name of a non-type template-parameter; or 2704 SourceLocation NonConstantLoc; 2705 llvm::APSInt Value; 2706 if (!ArgType->isIntegralType() && !ArgType->isEnumeralType()) { 2707 Diag(Arg->getSourceRange().getBegin(), 2708 diag::err_template_arg_not_integral_or_enumeral) 2709 << ArgType << Arg->getSourceRange(); 2710 Diag(Param->getLocation(), diag::note_template_param_here); 2711 return true; 2712 } else if (!Arg->isValueDependent() && 2713 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) { 2714 Diag(NonConstantLoc, diag::err_template_arg_not_ice) 2715 << ArgType << Arg->getSourceRange(); 2716 return true; 2717 } 2718 2719 // From here on out, all we care about are the unqualified forms 2720 // of the parameter and argument types. 2721 ParamType = ParamType.getUnqualifiedType(); 2722 ArgType = ArgType.getUnqualifiedType(); 2723 2724 // Try to convert the argument to the parameter's type. 2725 if (Context.hasSameType(ParamType, ArgType)) { 2726 // Okay: no conversion necessary 2727 } else if (CTAK == CTAK_Deduced) { 2728 // C++ [temp.deduct.type]p17: 2729 // If, in the declaration of a function template with a non-type 2730 // template-parameter, the non-type template- parameter is used 2731 // in an expression in the function parameter-list and, if the 2732 // corresponding template-argument is deduced, the 2733 // template-argument type shall match the type of the 2734 // template-parameter exactly, except that a template-argument 2735 // deduced from an array bound may be of any integral type. 2736 Diag(StartLoc, diag::err_deduced_non_type_template_arg_type_mismatch) 2737 << ArgType << ParamType; 2738 Diag(Param->getLocation(), diag::note_template_param_here); 2739 return true; 2740 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || 2741 !ParamType->isEnumeralType()) { 2742 // This is an integral promotion or conversion. 2743 ImpCastExprToType(Arg, ParamType, CastExpr::CK_IntegralCast); 2744 } else { 2745 // We can't perform this conversion. 2746 Diag(Arg->getSourceRange().getBegin(), 2747 diag::err_template_arg_not_convertible) 2748 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2749 Diag(Param->getLocation(), diag::note_template_param_here); 2750 return true; 2751 } 2752 2753 QualType IntegerType = Context.getCanonicalType(ParamType); 2754 if (const EnumType *Enum = IntegerType->getAs<EnumType>()) 2755 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); 2756 2757 if (!Arg->isValueDependent()) { 2758 llvm::APSInt OldValue = Value; 2759 2760 // Coerce the template argument's value to the value it will have 2761 // based on the template parameter's type. 2762 unsigned AllowedBits = Context.getTypeSize(IntegerType); 2763 if (Value.getBitWidth() != AllowedBits) 2764 Value.extOrTrunc(AllowedBits); 2765 Value.setIsSigned(IntegerType->isSignedIntegerType()); 2766 2767 // Complain if an unsigned parameter received a negative value. 2768 if (IntegerType->isUnsignedIntegerType() 2769 && (OldValue.isSigned() && OldValue.isNegative())) { 2770 Diag(Arg->getSourceRange().getBegin(), diag::warn_template_arg_negative) 2771 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2772 << Arg->getSourceRange(); 2773 Diag(Param->getLocation(), diag::note_template_param_here); 2774 } 2775 2776 // Complain if we overflowed the template parameter's type. 2777 unsigned RequiredBits; 2778 if (IntegerType->isUnsignedIntegerType()) 2779 RequiredBits = OldValue.getActiveBits(); 2780 else if (OldValue.isUnsigned()) 2781 RequiredBits = OldValue.getActiveBits() + 1; 2782 else 2783 RequiredBits = OldValue.getMinSignedBits(); 2784 if (RequiredBits > AllowedBits) { 2785 Diag(Arg->getSourceRange().getBegin(), 2786 diag::warn_template_arg_too_large) 2787 << OldValue.toString(10) << Value.toString(10) << Param->getType() 2788 << Arg->getSourceRange(); 2789 Diag(Param->getLocation(), diag::note_template_param_here); 2790 } 2791 } 2792 2793 // Add the value of this argument to the list of converted 2794 // arguments. We use the bitwidth and signedness of the template 2795 // parameter. 2796 if (Arg->isValueDependent()) { 2797 // The argument is value-dependent. Create a new 2798 // TemplateArgument with the converted expression. 2799 Converted = TemplateArgument(Arg); 2800 return false; 2801 } 2802 2803 Converted = TemplateArgument(Value, 2804 ParamType->isEnumeralType() ? ParamType 2805 : IntegerType); 2806 return false; 2807 } 2808 2809 DeclAccessPair FoundResult; // temporary for ResolveOverloadedFunction 2810 2811 // C++0x [temp.arg.nontype]p5 bullets 2, 4 and 6 permit conversion 2812 // from a template argument of type std::nullptr_t to a non-type 2813 // template parameter of type pointer to object, pointer to 2814 // function, or pointer-to-member, respectively. 2815 if (ArgType->isNullPtrType() && 2816 (ParamType->isPointerType() || ParamType->isMemberPointerType())) { 2817 Converted = TemplateArgument((NamedDecl *)0); 2818 return false; 2819 } 2820 2821 // Handle pointer-to-function, reference-to-function, and 2822 // pointer-to-member-function all in (roughly) the same way. 2823 if (// -- For a non-type template-parameter of type pointer to 2824 // function, only the function-to-pointer conversion (4.3) is 2825 // applied. If the template-argument represents a set of 2826 // overloaded functions (or a pointer to such), the matching 2827 // function is selected from the set (13.4). 2828 (ParamType->isPointerType() && 2829 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || 2830 // -- For a non-type template-parameter of type reference to 2831 // function, no conversions apply. If the template-argument 2832 // represents a set of overloaded functions, the matching 2833 // function is selected from the set (13.4). 2834 (ParamType->isReferenceType() && 2835 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || 2836 // -- For a non-type template-parameter of type pointer to 2837 // member function, no conversions apply. If the 2838 // template-argument represents a set of overloaded member 2839 // functions, the matching member function is selected from 2840 // the set (13.4). 2841 (ParamType->isMemberPointerType() && 2842 ParamType->getAs<MemberPointerType>()->getPointeeType() 2843 ->isFunctionType())) { 2844 2845 if (Arg->getType() == Context.OverloadTy) { 2846 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, ParamType, 2847 true, 2848 FoundResult)) { 2849 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2850 return true; 2851 2852 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2853 ArgType = Arg->getType(); 2854 } else 2855 return true; 2856 } 2857 2858 if (!ParamType->isMemberPointerType()) 2859 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2860 ParamType, 2861 Arg, Converted); 2862 2863 if (IsQualificationConversion(ArgType, ParamType.getNonReferenceType())) { 2864 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp, 2865 Arg->isLvalue(Context) == Expr::LV_Valid); 2866 } else if (!Context.hasSameUnqualifiedType(ArgType, 2867 ParamType.getNonReferenceType())) { 2868 // We can't perform this conversion. 2869 Diag(Arg->getSourceRange().getBegin(), 2870 diag::err_template_arg_not_convertible) 2871 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2872 Diag(Param->getLocation(), diag::note_template_param_here); 2873 return true; 2874 } 2875 2876 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2877 } 2878 2879 if (ParamType->isPointerType()) { 2880 // -- for a non-type template-parameter of type pointer to 2881 // object, qualification conversions (4.4) and the 2882 // array-to-pointer conversion (4.2) are applied. 2883 // C++0x also allows a value of std::nullptr_t. 2884 assert(ParamType->getAs<PointerType>()->getPointeeType()->isObjectType() && 2885 "Only object pointers allowed here"); 2886 2887 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2888 ParamType, 2889 Arg, Converted); 2890 } 2891 2892 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { 2893 // -- For a non-type template-parameter of type reference to 2894 // object, no conversions apply. The type referred to by the 2895 // reference may be more cv-qualified than the (otherwise 2896 // identical) type of the template-argument. The 2897 // template-parameter is bound directly to the 2898 // template-argument, which must be an lvalue. 2899 assert(ParamRefType->getPointeeType()->isObjectType() && 2900 "Only object references allowed here"); 2901 2902 if (Arg->getType() == Context.OverloadTy) { 2903 if (FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Arg, 2904 ParamRefType->getPointeeType(), 2905 true, 2906 FoundResult)) { 2907 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2908 return true; 2909 2910 Arg = FixOverloadedFunctionReference(Arg, FoundResult, Fn); 2911 ArgType = Arg->getType(); 2912 } else 2913 return true; 2914 } 2915 2916 return CheckTemplateArgumentAddressOfObjectOrFunction(*this, Param, 2917 ParamType, 2918 Arg, Converted); 2919 } 2920 2921 // -- For a non-type template-parameter of type pointer to data 2922 // member, qualification conversions (4.4) are applied. 2923 assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); 2924 2925 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) { 2926 // Types match exactly: nothing more to do here. 2927 } else if (IsQualificationConversion(ArgType, ParamType)) { 2928 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp, 2929 Arg->isLvalue(Context) == Expr::LV_Valid); 2930 } else { 2931 // We can't perform this conversion. 2932 Diag(Arg->getSourceRange().getBegin(), 2933 diag::err_template_arg_not_convertible) 2934 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2935 Diag(Param->getLocation(), diag::note_template_param_here); 2936 return true; 2937 } 2938 2939 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2940} 2941 2942/// \brief Check a template argument against its corresponding 2943/// template template parameter. 2944/// 2945/// This routine implements the semantics of C++ [temp.arg.template]. 2946/// It returns true if an error occurred, and false otherwise. 2947bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, 2948 const TemplateArgumentLoc &Arg) { 2949 TemplateName Name = Arg.getArgument().getAsTemplate(); 2950 TemplateDecl *Template = Name.getAsTemplateDecl(); 2951 if (!Template) { 2952 // Any dependent template name is fine. 2953 assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); 2954 return false; 2955 } 2956 2957 // C++ [temp.arg.template]p1: 2958 // A template-argument for a template template-parameter shall be 2959 // the name of a class template, expressed as id-expression. Only 2960 // primary class templates are considered when matching the 2961 // template template argument with the corresponding parameter; 2962 // partial specializations are not considered even if their 2963 // parameter lists match that of the template template parameter. 2964 // 2965 // Note that we also allow template template parameters here, which 2966 // will happen when we are dealing with, e.g., class template 2967 // partial specializations. 2968 if (!isa<ClassTemplateDecl>(Template) && 2969 !isa<TemplateTemplateParmDecl>(Template)) { 2970 assert(isa<FunctionTemplateDecl>(Template) && 2971 "Only function templates are possible here"); 2972 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); 2973 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) 2974 << Template; 2975 } 2976 2977 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), 2978 Param->getTemplateParameters(), 2979 true, 2980 TPL_TemplateTemplateArgumentMatch, 2981 Arg.getLocation()); 2982} 2983 2984/// \brief Given a non-type template argument that refers to a 2985/// declaration and the type of its corresponding non-type template 2986/// parameter, produce an expression that properly refers to that 2987/// declaration. 2988Sema::OwningExprResult 2989Sema::BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg, 2990 QualType ParamType, 2991 SourceLocation Loc) { 2992 assert(Arg.getKind() == TemplateArgument::Declaration && 2993 "Only declaration template arguments permitted here"); 2994 ValueDecl *VD = cast<ValueDecl>(Arg.getAsDecl()); 2995 2996 if (VD->getDeclContext()->isRecord() && 2997 (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD))) { 2998 // If the value is a class member, we might have a pointer-to-member. 2999 // Determine whether the non-type template template parameter is of 3000 // pointer-to-member type. If so, we need to build an appropriate 3001 // expression for a pointer-to-member, since a "normal" DeclRefExpr 3002 // would refer to the member itself. 3003 if (ParamType->isMemberPointerType()) { 3004 QualType ClassType 3005 = Context.getTypeDeclType(cast<RecordDecl>(VD->getDeclContext())); 3006 NestedNameSpecifier *Qualifier 3007 = NestedNameSpecifier::Create(Context, 0, false, ClassType.getTypePtr()); 3008 CXXScopeSpec SS; 3009 SS.setScopeRep(Qualifier); 3010 OwningExprResult RefExpr = BuildDeclRefExpr(VD, 3011 VD->getType().getNonReferenceType(), 3012 Loc, 3013 &SS); 3014 if (RefExpr.isInvalid()) 3015 return ExprError(); 3016 3017 RefExpr = CreateBuiltinUnaryOp(Loc, UnaryOperator::AddrOf, move(RefExpr)); 3018 assert(!RefExpr.isInvalid() && 3019 Context.hasSameType(((Expr*) RefExpr.get())->getType(), 3020 ParamType)); 3021 return move(RefExpr); 3022 } 3023 } 3024 3025 QualType T = VD->getType().getNonReferenceType(); 3026 if (ParamType->isPointerType()) { 3027 // When the non-type template parameter is a pointer, take the 3028 // address of the declaration. 3029 OwningExprResult RefExpr = BuildDeclRefExpr(VD, T, Loc); 3030 if (RefExpr.isInvalid()) 3031 return ExprError(); 3032 3033 if (T->isFunctionType() || T->isArrayType()) { 3034 // Decay functions and arrays. 3035 Expr *RefE = (Expr *)RefExpr.get(); 3036 DefaultFunctionArrayConversion(RefE); 3037 if (RefE != RefExpr.get()) { 3038 RefExpr.release(); 3039 RefExpr = Owned(RefE); 3040 } 3041 3042 return move(RefExpr); 3043 } 3044 3045 // Take the address of everything else 3046 return CreateBuiltinUnaryOp(Loc, UnaryOperator::AddrOf, move(RefExpr)); 3047 } 3048 3049 // If the non-type template parameter has reference type, qualify the 3050 // resulting declaration reference with the extra qualifiers on the 3051 // type that the reference refers to. 3052 if (const ReferenceType *TargetRef = ParamType->getAs<ReferenceType>()) 3053 T = Context.getQualifiedType(T, TargetRef->getPointeeType().getQualifiers()); 3054 3055 return BuildDeclRefExpr(VD, T, Loc); 3056} 3057 3058/// \brief Construct a new expression that refers to the given 3059/// integral template argument with the given source-location 3060/// information. 3061/// 3062/// This routine takes care of the mapping from an integral template 3063/// argument (which may have any integral type) to the appropriate 3064/// literal value. 3065Sema::OwningExprResult 3066Sema::BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg, 3067 SourceLocation Loc) { 3068 assert(Arg.getKind() == TemplateArgument::Integral && 3069 "Operation is only value for integral template arguments"); 3070 QualType T = Arg.getIntegralType(); 3071 if (T->isCharType() || T->isWideCharType()) 3072 return Owned(new (Context) CharacterLiteral( 3073 Arg.getAsIntegral()->getZExtValue(), 3074 T->isWideCharType(), 3075 T, 3076 Loc)); 3077 if (T->isBooleanType()) 3078 return Owned(new (Context) CXXBoolLiteralExpr( 3079 Arg.getAsIntegral()->getBoolValue(), 3080 T, 3081 Loc)); 3082 3083 return Owned(new (Context) IntegerLiteral(*Arg.getAsIntegral(), T, Loc)); 3084} 3085 3086 3087/// \brief Determine whether the given template parameter lists are 3088/// equivalent. 3089/// 3090/// \param New The new template parameter list, typically written in the 3091/// source code as part of a new template declaration. 3092/// 3093/// \param Old The old template parameter list, typically found via 3094/// name lookup of the template declared with this template parameter 3095/// list. 3096/// 3097/// \param Complain If true, this routine will produce a diagnostic if 3098/// the template parameter lists are not equivalent. 3099/// 3100/// \param Kind describes how we are to match the template parameter lists. 3101/// 3102/// \param TemplateArgLoc If this source location is valid, then we 3103/// are actually checking the template parameter list of a template 3104/// argument (New) against the template parameter list of its 3105/// corresponding template template parameter (Old). We produce 3106/// slightly different diagnostics in this scenario. 3107/// 3108/// \returns True if the template parameter lists are equal, false 3109/// otherwise. 3110bool 3111Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, 3112 TemplateParameterList *Old, 3113 bool Complain, 3114 TemplateParameterListEqualKind Kind, 3115 SourceLocation TemplateArgLoc) { 3116 if (Old->size() != New->size()) { 3117 if (Complain) { 3118 unsigned NextDiag = diag::err_template_param_list_different_arity; 3119 if (TemplateArgLoc.isValid()) { 3120 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3121 NextDiag = diag::note_template_param_list_different_arity; 3122 } 3123 Diag(New->getTemplateLoc(), NextDiag) 3124 << (New->size() > Old->size()) 3125 << (Kind != TPL_TemplateMatch) 3126 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); 3127 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) 3128 << (Kind != TPL_TemplateMatch) 3129 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); 3130 } 3131 3132 return false; 3133 } 3134 3135 for (TemplateParameterList::iterator OldParm = Old->begin(), 3136 OldParmEnd = Old->end(), NewParm = New->begin(); 3137 OldParm != OldParmEnd; ++OldParm, ++NewParm) { 3138 if ((*OldParm)->getKind() != (*NewParm)->getKind()) { 3139 if (Complain) { 3140 unsigned NextDiag = diag::err_template_param_different_kind; 3141 if (TemplateArgLoc.isValid()) { 3142 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 3143 NextDiag = diag::note_template_param_different_kind; 3144 } 3145 Diag((*NewParm)->getLocation(), NextDiag) 3146 << (Kind != TPL_TemplateMatch); 3147 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration) 3148 << (Kind != TPL_TemplateMatch); 3149 } 3150 return false; 3151 } 3152 3153 if (isa<TemplateTypeParmDecl>(*OldParm)) { 3154 // Okay; all template type parameters are equivalent (since we 3155 // know we're at the same index). 3156 } else if (NonTypeTemplateParmDecl *OldNTTP 3157 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) { 3158 // The types of non-type template parameters must agree. 3159 NonTypeTemplateParmDecl *NewNTTP 3160 = cast<NonTypeTemplateParmDecl>(*NewParm); 3161 3162 // If we are matching a template template argument to a template 3163 // template parameter and one of the non-type template parameter types 3164 // is dependent, then we must wait until template instantiation time 3165 // to actually compare the arguments. 3166 if (Kind == TPL_TemplateTemplateArgumentMatch && 3167 (OldNTTP->getType()->isDependentType() || 3168 NewNTTP->getType()->isDependentType())) 3169 continue; 3170 3171 if (Context.getCanonicalType(OldNTTP->getType()) != 3172 Context.getCanonicalType(NewNTTP->getType())) { 3173 if (Complain) { 3174 unsigned NextDiag = diag::err_template_nontype_parm_different_type; 3175 if (TemplateArgLoc.isValid()) { 3176 Diag(TemplateArgLoc, 3177 diag::err_template_arg_template_params_mismatch); 3178 NextDiag = diag::note_template_nontype_parm_different_type; 3179 } 3180 Diag(NewNTTP->getLocation(), NextDiag) 3181 << NewNTTP->getType() 3182 << (Kind != TPL_TemplateMatch); 3183 Diag(OldNTTP->getLocation(), 3184 diag::note_template_nontype_parm_prev_declaration) 3185 << OldNTTP->getType(); 3186 } 3187 return false; 3188 } 3189 } else { 3190 // The template parameter lists of template template 3191 // parameters must agree. 3192 assert(isa<TemplateTemplateParmDecl>(*OldParm) && 3193 "Only template template parameters handled here"); 3194 TemplateTemplateParmDecl *OldTTP 3195 = cast<TemplateTemplateParmDecl>(*OldParm); 3196 TemplateTemplateParmDecl *NewTTP 3197 = cast<TemplateTemplateParmDecl>(*NewParm); 3198 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), 3199 OldTTP->getTemplateParameters(), 3200 Complain, 3201 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind), 3202 TemplateArgLoc)) 3203 return false; 3204 } 3205 } 3206 3207 return true; 3208} 3209 3210/// \brief Check whether a template can be declared within this scope. 3211/// 3212/// If the template declaration is valid in this scope, returns 3213/// false. Otherwise, issues a diagnostic and returns true. 3214bool 3215Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { 3216 // Find the nearest enclosing declaration scope. 3217 while ((S->getFlags() & Scope::DeclScope) == 0 || 3218 (S->getFlags() & Scope::TemplateParamScope) != 0) 3219 S = S->getParent(); 3220 3221 // C++ [temp]p2: 3222 // A template-declaration can appear only as a namespace scope or 3223 // class scope declaration. 3224 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 3225 if (Ctx && isa<LinkageSpecDecl>(Ctx) && 3226 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) 3227 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) 3228 << TemplateParams->getSourceRange(); 3229 3230 while (Ctx && isa<LinkageSpecDecl>(Ctx)) 3231 Ctx = Ctx->getParent(); 3232 3233 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) 3234 return false; 3235 3236 return Diag(TemplateParams->getTemplateLoc(), 3237 diag::err_template_outside_namespace_or_class_scope) 3238 << TemplateParams->getSourceRange(); 3239} 3240 3241/// \brief Determine what kind of template specialization the given declaration 3242/// is. 3243static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) { 3244 if (!D) 3245 return TSK_Undeclared; 3246 3247 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) 3248 return Record->getTemplateSpecializationKind(); 3249 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) 3250 return Function->getTemplateSpecializationKind(); 3251 if (VarDecl *Var = dyn_cast<VarDecl>(D)) 3252 return Var->getTemplateSpecializationKind(); 3253 3254 return TSK_Undeclared; 3255} 3256 3257/// \brief Check whether a specialization is well-formed in the current 3258/// context. 3259/// 3260/// This routine determines whether a template specialization can be declared 3261/// in the current context (C++ [temp.expl.spec]p2). 3262/// 3263/// \param S the semantic analysis object for which this check is being 3264/// performed. 3265/// 3266/// \param Specialized the entity being specialized or instantiated, which 3267/// may be a kind of template (class template, function template, etc.) or 3268/// a member of a class template (member function, static data member, 3269/// member class). 3270/// 3271/// \param PrevDecl the previous declaration of this entity, if any. 3272/// 3273/// \param Loc the location of the explicit specialization or instantiation of 3274/// this entity. 3275/// 3276/// \param IsPartialSpecialization whether this is a partial specialization of 3277/// a class template. 3278/// 3279/// \returns true if there was an error that we cannot recover from, false 3280/// otherwise. 3281static bool CheckTemplateSpecializationScope(Sema &S, 3282 NamedDecl *Specialized, 3283 NamedDecl *PrevDecl, 3284 SourceLocation Loc, 3285 bool IsPartialSpecialization) { 3286 // Keep these "kind" numbers in sync with the %select statements in the 3287 // various diagnostics emitted by this routine. 3288 int EntityKind = 0; 3289 bool isTemplateSpecialization = false; 3290 if (isa<ClassTemplateDecl>(Specialized)) { 3291 EntityKind = IsPartialSpecialization? 1 : 0; 3292 isTemplateSpecialization = true; 3293 } else if (isa<FunctionTemplateDecl>(Specialized)) { 3294 EntityKind = 2; 3295 isTemplateSpecialization = true; 3296 } else if (isa<CXXMethodDecl>(Specialized)) 3297 EntityKind = 3; 3298 else if (isa<VarDecl>(Specialized)) 3299 EntityKind = 4; 3300 else if (isa<RecordDecl>(Specialized)) 3301 EntityKind = 5; 3302 else { 3303 S.Diag(Loc, diag::err_template_spec_unknown_kind); 3304 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3305 return true; 3306 } 3307 3308 // C++ [temp.expl.spec]p2: 3309 // An explicit specialization shall be declared in the namespace 3310 // of which the template is a member, or, for member templates, in 3311 // the namespace of which the enclosing class or enclosing class 3312 // template is a member. An explicit specialization of a member 3313 // function, member class or static data member of a class 3314 // template shall be declared in the namespace of which the class 3315 // template is a member. Such a declaration may also be a 3316 // definition. If the declaration is not a definition, the 3317 // specialization may be defined later in the name- space in which 3318 // the explicit specialization was declared, or in a namespace 3319 // that encloses the one in which the explicit specialization was 3320 // declared. 3321 if (S.CurContext->getLookupContext()->isFunctionOrMethod()) { 3322 S.Diag(Loc, diag::err_template_spec_decl_function_scope) 3323 << Specialized; 3324 return true; 3325 } 3326 3327 if (S.CurContext->isRecord() && !IsPartialSpecialization) { 3328 S.Diag(Loc, diag::err_template_spec_decl_class_scope) 3329 << Specialized; 3330 return true; 3331 } 3332 3333 // C++ [temp.class.spec]p6: 3334 // A class template partial specialization may be declared or redeclared 3335 // in any namespace scope in which its definition may be defined (14.5.1 3336 // and 14.5.2). 3337 bool ComplainedAboutScope = false; 3338 DeclContext *SpecializedContext 3339 = Specialized->getDeclContext()->getEnclosingNamespaceContext(); 3340 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); 3341 if ((!PrevDecl || 3342 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || 3343 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ 3344 // There is no prior declaration of this entity, so this 3345 // specialization must be in the same context as the template 3346 // itself. 3347 if (!DC->Equals(SpecializedContext)) { 3348 if (isa<TranslationUnitDecl>(SpecializedContext)) 3349 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) 3350 << EntityKind << Specialized; 3351 else if (isa<NamespaceDecl>(SpecializedContext)) 3352 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope) 3353 << EntityKind << Specialized 3354 << cast<NamedDecl>(SpecializedContext); 3355 3356 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3357 ComplainedAboutScope = true; 3358 } 3359 } 3360 3361 // Make sure that this redeclaration (or definition) occurs in an enclosing 3362 // namespace. 3363 // Note that HandleDeclarator() performs this check for explicit 3364 // specializations of function templates, static data members, and member 3365 // functions, so we skip the check here for those kinds of entities. 3366 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. 3367 // Should we refactor that check, so that it occurs later? 3368 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && 3369 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || 3370 isa<FunctionDecl>(Specialized))) { 3371 if (isa<TranslationUnitDecl>(SpecializedContext)) 3372 S.Diag(Loc, diag::err_template_spec_redecl_global_scope) 3373 << EntityKind << Specialized; 3374 else if (isa<NamespaceDecl>(SpecializedContext)) 3375 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) 3376 << EntityKind << Specialized 3377 << cast<NamedDecl>(SpecializedContext); 3378 3379 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 3380 } 3381 3382 // FIXME: check for specialization-after-instantiation errors and such. 3383 3384 return false; 3385} 3386 3387/// \brief Check the non-type template arguments of a class template 3388/// partial specialization according to C++ [temp.class.spec]p9. 3389/// 3390/// \param TemplateParams the template parameters of the primary class 3391/// template. 3392/// 3393/// \param TemplateArg the template arguments of the class template 3394/// partial specialization. 3395/// 3396/// \param MirrorsPrimaryTemplate will be set true if the class 3397/// template partial specialization arguments are identical to the 3398/// implicit template arguments of the primary template. This is not 3399/// necessarily an error (C++0x), and it is left to the caller to diagnose 3400/// this condition when it is an error. 3401/// 3402/// \returns true if there was an error, false otherwise. 3403bool Sema::CheckClassTemplatePartialSpecializationArgs( 3404 TemplateParameterList *TemplateParams, 3405 const TemplateArgumentListBuilder &TemplateArgs, 3406 bool &MirrorsPrimaryTemplate) { 3407 // FIXME: the interface to this function will have to change to 3408 // accommodate variadic templates. 3409 MirrorsPrimaryTemplate = true; 3410 3411 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments(); 3412 3413 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3414 // Determine whether the template argument list of the partial 3415 // specialization is identical to the implicit argument list of 3416 // the primary template. The caller may need to diagnostic this as 3417 // an error per C++ [temp.class.spec]p9b3. 3418 if (MirrorsPrimaryTemplate) { 3419 if (TemplateTypeParmDecl *TTP 3420 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) { 3421 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) != 3422 Context.getCanonicalType(ArgList[I].getAsType())) 3423 MirrorsPrimaryTemplate = false; 3424 } else if (TemplateTemplateParmDecl *TTP 3425 = dyn_cast<TemplateTemplateParmDecl>( 3426 TemplateParams->getParam(I))) { 3427 TemplateName Name = ArgList[I].getAsTemplate(); 3428 TemplateTemplateParmDecl *ArgDecl 3429 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()); 3430 if (!ArgDecl || 3431 ArgDecl->getIndex() != TTP->getIndex() || 3432 ArgDecl->getDepth() != TTP->getDepth()) 3433 MirrorsPrimaryTemplate = false; 3434 } 3435 } 3436 3437 NonTypeTemplateParmDecl *Param 3438 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); 3439 if (!Param) { 3440 continue; 3441 } 3442 3443 Expr *ArgExpr = ArgList[I].getAsExpr(); 3444 if (!ArgExpr) { 3445 MirrorsPrimaryTemplate = false; 3446 continue; 3447 } 3448 3449 // C++ [temp.class.spec]p8: 3450 // A non-type argument is non-specialized if it is the name of a 3451 // non-type parameter. All other non-type arguments are 3452 // specialized. 3453 // 3454 // Below, we check the two conditions that only apply to 3455 // specialized non-type arguments, so skip any non-specialized 3456 // arguments. 3457 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) 3458 if (NonTypeTemplateParmDecl *NTTP 3459 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) { 3460 if (MirrorsPrimaryTemplate && 3461 (Param->getIndex() != NTTP->getIndex() || 3462 Param->getDepth() != NTTP->getDepth())) 3463 MirrorsPrimaryTemplate = false; 3464 3465 continue; 3466 } 3467 3468 // C++ [temp.class.spec]p9: 3469 // Within the argument list of a class template partial 3470 // specialization, the following restrictions apply: 3471 // -- A partially specialized non-type argument expression 3472 // shall not involve a template parameter of the partial 3473 // specialization except when the argument expression is a 3474 // simple identifier. 3475 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { 3476 Diag(ArgExpr->getLocStart(), 3477 diag::err_dependent_non_type_arg_in_partial_spec) 3478 << ArgExpr->getSourceRange(); 3479 return true; 3480 } 3481 3482 // -- The type of a template parameter corresponding to a 3483 // specialized non-type argument shall not be dependent on a 3484 // parameter of the specialization. 3485 if (Param->getType()->isDependentType()) { 3486 Diag(ArgExpr->getLocStart(), 3487 diag::err_dependent_typed_non_type_arg_in_partial_spec) 3488 << Param->getType() 3489 << ArgExpr->getSourceRange(); 3490 Diag(Param->getLocation(), diag::note_template_param_here); 3491 return true; 3492 } 3493 3494 MirrorsPrimaryTemplate = false; 3495 } 3496 3497 return false; 3498} 3499 3500/// \brief Retrieve the previous declaration of the given declaration. 3501static NamedDecl *getPreviousDecl(NamedDecl *ND) { 3502 if (VarDecl *VD = dyn_cast<VarDecl>(ND)) 3503 return VD->getPreviousDeclaration(); 3504 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) 3505 return FD->getPreviousDeclaration(); 3506 if (TagDecl *TD = dyn_cast<TagDecl>(ND)) 3507 return TD->getPreviousDeclaration(); 3508 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND)) 3509 return TD->getPreviousDeclaration(); 3510 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND)) 3511 return FTD->getPreviousDeclaration(); 3512 if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(ND)) 3513 return CTD->getPreviousDeclaration(); 3514 return 0; 3515} 3516 3517Sema::DeclResult 3518Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, 3519 TagUseKind TUK, 3520 SourceLocation KWLoc, 3521 CXXScopeSpec &SS, 3522 TemplateTy TemplateD, 3523 SourceLocation TemplateNameLoc, 3524 SourceLocation LAngleLoc, 3525 ASTTemplateArgsPtr TemplateArgsIn, 3526 SourceLocation RAngleLoc, 3527 AttributeList *Attr, 3528 MultiTemplateParamsArg TemplateParameterLists) { 3529 assert(TUK != TUK_Reference && "References are not specializations"); 3530 3531 // Find the class template we're specializing 3532 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 3533 ClassTemplateDecl *ClassTemplate 3534 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); 3535 3536 if (!ClassTemplate) { 3537 Diag(TemplateNameLoc, diag::err_not_class_template_specialization) 3538 << (Name.getAsTemplateDecl() && 3539 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); 3540 return true; 3541 } 3542 3543 bool isExplicitSpecialization = false; 3544 bool isPartialSpecialization = false; 3545 3546 // Check the validity of the template headers that introduce this 3547 // template. 3548 // FIXME: We probably shouldn't complain about these headers for 3549 // friend declarations. 3550 TemplateParameterList *TemplateParams 3551 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS, 3552 (TemplateParameterList**)TemplateParameterLists.get(), 3553 TemplateParameterLists.size(), 3554 TUK == TUK_Friend, 3555 isExplicitSpecialization); 3556 if (TemplateParams && TemplateParams->size() > 0) { 3557 isPartialSpecialization = true; 3558 3559 // C++ [temp.class.spec]p10: 3560 // The template parameter list of a specialization shall not 3561 // contain default template argument values. 3562 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 3563 Decl *Param = TemplateParams->getParam(I); 3564 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { 3565 if (TTP->hasDefaultArgument()) { 3566 Diag(TTP->getDefaultArgumentLoc(), 3567 diag::err_default_arg_in_partial_spec); 3568 TTP->removeDefaultArgument(); 3569 } 3570 } else if (NonTypeTemplateParmDecl *NTTP 3571 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 3572 if (Expr *DefArg = NTTP->getDefaultArgument()) { 3573 Diag(NTTP->getDefaultArgumentLoc(), 3574 diag::err_default_arg_in_partial_spec) 3575 << DefArg->getSourceRange(); 3576 NTTP->setDefaultArgument(0); 3577 DefArg->Destroy(Context); 3578 } 3579 } else { 3580 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); 3581 if (TTP->hasDefaultArgument()) { 3582 Diag(TTP->getDefaultArgument().getLocation(), 3583 diag::err_default_arg_in_partial_spec) 3584 << TTP->getDefaultArgument().getSourceRange(); 3585 TTP->setDefaultArgument(TemplateArgumentLoc()); 3586 } 3587 } 3588 } 3589 } else if (TemplateParams) { 3590 if (TUK == TUK_Friend) 3591 Diag(KWLoc, diag::err_template_spec_friend) 3592 << FixItHint::CreateRemoval( 3593 SourceRange(TemplateParams->getTemplateLoc(), 3594 TemplateParams->getRAngleLoc())) 3595 << SourceRange(LAngleLoc, RAngleLoc); 3596 else 3597 isExplicitSpecialization = true; 3598 } else if (TUK != TUK_Friend) { 3599 Diag(KWLoc, diag::err_template_spec_needs_header) 3600 << FixItHint::CreateInsertion(KWLoc, "template<> "); 3601 isExplicitSpecialization = true; 3602 } 3603 3604 // Check that the specialization uses the same tag kind as the 3605 // original template. 3606 TagDecl::TagKind Kind; 3607 switch (TagSpec) { 3608 default: assert(0 && "Unknown tag type!"); 3609 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3610 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3611 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3612 } 3613 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 3614 Kind, KWLoc, 3615 *ClassTemplate->getIdentifier())) { 3616 Diag(KWLoc, diag::err_use_with_wrong_tag) 3617 << ClassTemplate 3618 << FixItHint::CreateReplacement(KWLoc, 3619 ClassTemplate->getTemplatedDecl()->getKindName()); 3620 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 3621 diag::note_previous_use); 3622 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 3623 } 3624 3625 // Translate the parser's template argument list in our AST format. 3626 TemplateArgumentListInfo TemplateArgs; 3627 TemplateArgs.setLAngleLoc(LAngleLoc); 3628 TemplateArgs.setRAngleLoc(RAngleLoc); 3629 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 3630 3631 // Check that the template argument list is well-formed for this 3632 // template. 3633 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 3634 TemplateArgs.size()); 3635 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 3636 TemplateArgs, false, Converted)) 3637 return true; 3638 3639 assert((Converted.structuredSize() == 3640 ClassTemplate->getTemplateParameters()->size()) && 3641 "Converted template argument list is too short!"); 3642 3643 // Find the class template (partial) specialization declaration that 3644 // corresponds to these arguments. 3645 llvm::FoldingSetNodeID ID; 3646 if (isPartialSpecialization) { 3647 bool MirrorsPrimaryTemplate; 3648 if (CheckClassTemplatePartialSpecializationArgs( 3649 ClassTemplate->getTemplateParameters(), 3650 Converted, MirrorsPrimaryTemplate)) 3651 return true; 3652 3653 if (MirrorsPrimaryTemplate) { 3654 // C++ [temp.class.spec]p9b3: 3655 // 3656 // -- The argument list of the specialization shall not be identical 3657 // to the implicit argument list of the primary template. 3658 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) 3659 << (TUK == TUK_Definition) 3660 << FixItHint::CreateRemoval(SourceRange(LAngleLoc, RAngleLoc)); 3661 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, 3662 ClassTemplate->getIdentifier(), 3663 TemplateNameLoc, 3664 Attr, 3665 TemplateParams, 3666 AS_none); 3667 } 3668 3669 // FIXME: Diagnose friend partial specializations 3670 3671 if (!Name.isDependent() && 3672 !TemplateSpecializationType::anyDependentTemplateArguments( 3673 TemplateArgs.getArgumentArray(), 3674 TemplateArgs.size())) { 3675 Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized) 3676 << ClassTemplate->getDeclName(); 3677 isPartialSpecialization = false; 3678 } else { 3679 // FIXME: Template parameter list matters, too 3680 ClassTemplatePartialSpecializationDecl::Profile(ID, 3681 Converted.getFlatArguments(), 3682 Converted.flatSize(), 3683 Context); 3684 } 3685 } 3686 3687 if (!isPartialSpecialization) 3688 ClassTemplateSpecializationDecl::Profile(ID, 3689 Converted.getFlatArguments(), 3690 Converted.flatSize(), 3691 Context); 3692 void *InsertPos = 0; 3693 ClassTemplateSpecializationDecl *PrevDecl = 0; 3694 3695 if (isPartialSpecialization) 3696 PrevDecl 3697 = ClassTemplate->getPartialSpecializations().FindNodeOrInsertPos(ID, 3698 InsertPos); 3699 else 3700 PrevDecl 3701 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 3702 3703 ClassTemplateSpecializationDecl *Specialization = 0; 3704 3705 // Check whether we can declare a class template specialization in 3706 // the current scope. 3707 if (TUK != TUK_Friend && 3708 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, 3709 TemplateNameLoc, 3710 isPartialSpecialization)) 3711 return true; 3712 3713 // The canonical type 3714 QualType CanonType; 3715 if (PrevDecl && 3716 (PrevDecl->getSpecializationKind() == TSK_Undeclared || 3717 TUK == TUK_Friend)) { 3718 // Since the only prior class template specialization with these 3719 // arguments was referenced but not declared, or we're only 3720 // referencing this specialization as a friend, reuse that 3721 // declaration node as our own, updating its source location to 3722 // reflect our new declaration. 3723 Specialization = PrevDecl; 3724 Specialization->setLocation(TemplateNameLoc); 3725 PrevDecl = 0; 3726 CanonType = Context.getTypeDeclType(Specialization); 3727 } else if (isPartialSpecialization) { 3728 // Build the canonical type that describes the converted template 3729 // arguments of the class template partial specialization. 3730 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); 3731 CanonType = Context.getTemplateSpecializationType(CanonTemplate, 3732 Converted.getFlatArguments(), 3733 Converted.flatSize()); 3734 3735 // Create a new class template partial specialization declaration node. 3736 ClassTemplatePartialSpecializationDecl *PrevPartial 3737 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); 3738 ClassTemplatePartialSpecializationDecl *Partial 3739 = ClassTemplatePartialSpecializationDecl::Create(Context, 3740 ClassTemplate->getDeclContext(), 3741 TemplateNameLoc, 3742 TemplateParams, 3743 ClassTemplate, 3744 Converted, 3745 TemplateArgs, 3746 CanonType, 3747 PrevPartial); 3748 SetNestedNameSpecifier(Partial, SS); 3749 3750 if (PrevPartial) { 3751 ClassTemplate->getPartialSpecializations().RemoveNode(PrevPartial); 3752 ClassTemplate->getPartialSpecializations().GetOrInsertNode(Partial); 3753 } else { 3754 ClassTemplate->getPartialSpecializations().InsertNode(Partial, InsertPos); 3755 } 3756 Specialization = Partial; 3757 3758 // If we are providing an explicit specialization of a member class 3759 // template specialization, make a note of that. 3760 if (PrevPartial && PrevPartial->getInstantiatedFromMember()) 3761 PrevPartial->setMemberSpecialization(); 3762 3763 // Check that all of the template parameters of the class template 3764 // partial specialization are deducible from the template 3765 // arguments. If not, this class template partial specialization 3766 // will never be used. 3767 llvm::SmallVector<bool, 8> DeducibleParams; 3768 DeducibleParams.resize(TemplateParams->size()); 3769 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true, 3770 TemplateParams->getDepth(), 3771 DeducibleParams); 3772 unsigned NumNonDeducible = 0; 3773 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) 3774 if (!DeducibleParams[I]) 3775 ++NumNonDeducible; 3776 3777 if (NumNonDeducible) { 3778 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible) 3779 << (NumNonDeducible > 1) 3780 << SourceRange(TemplateNameLoc, RAngleLoc); 3781 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) { 3782 if (!DeducibleParams[I]) { 3783 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I)); 3784 if (Param->getDeclName()) 3785 Diag(Param->getLocation(), 3786 diag::note_partial_spec_unused_parameter) 3787 << Param->getDeclName(); 3788 else 3789 Diag(Param->getLocation(), 3790 diag::note_partial_spec_unused_parameter) 3791 << std::string("<anonymous>"); 3792 } 3793 } 3794 } 3795 } else { 3796 // Create a new class template specialization declaration node for 3797 // this explicit specialization or friend declaration. 3798 Specialization 3799 = ClassTemplateSpecializationDecl::Create(Context, 3800 ClassTemplate->getDeclContext(), 3801 TemplateNameLoc, 3802 ClassTemplate, 3803 Converted, 3804 PrevDecl); 3805 SetNestedNameSpecifier(Specialization, SS); 3806 3807 if (PrevDecl) { 3808 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 3809 ClassTemplate->getSpecializations().GetOrInsertNode(Specialization); 3810 } else { 3811 ClassTemplate->getSpecializations().InsertNode(Specialization, 3812 InsertPos); 3813 } 3814 3815 CanonType = Context.getTypeDeclType(Specialization); 3816 } 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 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { 3825 bool Okay = false; 3826 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 3827 // Is there any previous explicit specialization declaration? 3828 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) { 3829 Okay = true; 3830 break; 3831 } 3832 } 3833 3834 if (!Okay) { 3835 SourceRange Range(TemplateNameLoc, RAngleLoc); 3836 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) 3837 << Context.getTypeDeclType(Specialization) << Range; 3838 3839 Diag(PrevDecl->getPointOfInstantiation(), 3840 diag::note_instantiation_required_here) 3841 << (PrevDecl->getTemplateSpecializationKind() 3842 != TSK_ImplicitInstantiation); 3843 return true; 3844 } 3845 } 3846 3847 // If this is not a friend, note that this is an explicit specialization. 3848 if (TUK != TUK_Friend) 3849 Specialization->setSpecializationKind(TSK_ExplicitSpecialization); 3850 3851 // Check that this isn't a redefinition of this specialization. 3852 if (TUK == TUK_Definition) { 3853 if (RecordDecl *Def = Specialization->getDefinition()) { 3854 SourceRange Range(TemplateNameLoc, RAngleLoc); 3855 Diag(TemplateNameLoc, diag::err_redefinition) 3856 << Context.getTypeDeclType(Specialization) << Range; 3857 Diag(Def->getLocation(), diag::note_previous_definition); 3858 Specialization->setInvalidDecl(); 3859 return true; 3860 } 3861 } 3862 3863 // Build the fully-sugared type for this class template 3864 // specialization as the user wrote in the specialization 3865 // itself. This means that we'll pretty-print the type retrieved 3866 // from the specialization's declaration the way that the user 3867 // actually wrote the specialization, rather than formatting the 3868 // name based on the "canonical" representation used to store the 3869 // template arguments in the specialization. 3870 TypeSourceInfo *WrittenTy 3871 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 3872 TemplateArgs, CanonType); 3873 if (TUK != TUK_Friend) 3874 Specialization->setTypeAsWritten(WrittenTy); 3875 TemplateArgsIn.release(); 3876 3877 // C++ [temp.expl.spec]p9: 3878 // A template explicit specialization is in the scope of the 3879 // namespace in which the template was defined. 3880 // 3881 // We actually implement this paragraph where we set the semantic 3882 // context (in the creation of the ClassTemplateSpecializationDecl), 3883 // but we also maintain the lexical context where the actual 3884 // definition occurs. 3885 Specialization->setLexicalDeclContext(CurContext); 3886 3887 // We may be starting the definition of this specialization. 3888 if (TUK == TUK_Definition) 3889 Specialization->startDefinition(); 3890 3891 if (TUK == TUK_Friend) { 3892 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 3893 TemplateNameLoc, 3894 WrittenTy, 3895 /*FIXME:*/KWLoc); 3896 Friend->setAccess(AS_public); 3897 CurContext->addDecl(Friend); 3898 } else { 3899 // Add the specialization into its lexical context, so that it can 3900 // be seen when iterating through the list of declarations in that 3901 // context. However, specializations are not found by name lookup. 3902 CurContext->addDecl(Specialization); 3903 } 3904 return DeclPtrTy::make(Specialization); 3905} 3906 3907Sema::DeclPtrTy 3908Sema::ActOnTemplateDeclarator(Scope *S, 3909 MultiTemplateParamsArg TemplateParameterLists, 3910 Declarator &D) { 3911 return HandleDeclarator(S, D, move(TemplateParameterLists), false); 3912} 3913 3914Sema::DeclPtrTy 3915Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, 3916 MultiTemplateParamsArg TemplateParameterLists, 3917 Declarator &D) { 3918 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3919 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3920 "Not a function declarator!"); 3921 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3922 3923 if (FTI.hasPrototype) { 3924 // FIXME: Diagnose arguments without names in C. 3925 } 3926 3927 Scope *ParentScope = FnBodyScope->getParent(); 3928 3929 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3930 move(TemplateParameterLists), 3931 /*IsFunctionDefinition=*/true); 3932 if (FunctionTemplateDecl *FunctionTemplate 3933 = dyn_cast_or_null<FunctionTemplateDecl>(DP.getAs<Decl>())) 3934 return ActOnStartOfFunctionDef(FnBodyScope, 3935 DeclPtrTy::make(FunctionTemplate->getTemplatedDecl())); 3936 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP.getAs<Decl>())) 3937 return ActOnStartOfFunctionDef(FnBodyScope, DeclPtrTy::make(Function)); 3938 return DeclPtrTy(); 3939} 3940 3941/// \brief Strips various properties off an implicit instantiation 3942/// that has just been explicitly specialized. 3943static void StripImplicitInstantiation(NamedDecl *D) { 3944 D->invalidateAttrs(); 3945 3946 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 3947 FD->setInlineSpecified(false); 3948 } 3949} 3950 3951/// \brief Diagnose cases where we have an explicit template specialization 3952/// before/after an explicit template instantiation, producing diagnostics 3953/// for those cases where they are required and determining whether the 3954/// new specialization/instantiation will have any effect. 3955/// 3956/// \param NewLoc the location of the new explicit specialization or 3957/// instantiation. 3958/// 3959/// \param NewTSK the kind of the new explicit specialization or instantiation. 3960/// 3961/// \param PrevDecl the previous declaration of the entity. 3962/// 3963/// \param PrevTSK the kind of the old explicit specialization or instantiatin. 3964/// 3965/// \param PrevPointOfInstantiation if valid, indicates where the previus 3966/// declaration was instantiated (either implicitly or explicitly). 3967/// 3968/// \param SuppressNew will be set to true to indicate that the new 3969/// specialization or instantiation has no effect and should be ignored. 3970/// 3971/// \returns true if there was an error that should prevent the introduction of 3972/// the new declaration into the AST, false otherwise. 3973bool 3974Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, 3975 TemplateSpecializationKind NewTSK, 3976 NamedDecl *PrevDecl, 3977 TemplateSpecializationKind PrevTSK, 3978 SourceLocation PrevPointOfInstantiation, 3979 bool &SuppressNew) { 3980 SuppressNew = false; 3981 3982 switch (NewTSK) { 3983 case TSK_Undeclared: 3984 case TSK_ImplicitInstantiation: 3985 assert(false && "Don't check implicit instantiations here"); 3986 return false; 3987 3988 case TSK_ExplicitSpecialization: 3989 switch (PrevTSK) { 3990 case TSK_Undeclared: 3991 case TSK_ExplicitSpecialization: 3992 // Okay, we're just specializing something that is either already 3993 // explicitly specialized or has merely been mentioned without any 3994 // instantiation. 3995 return false; 3996 3997 case TSK_ImplicitInstantiation: 3998 if (PrevPointOfInstantiation.isInvalid()) { 3999 // The declaration itself has not actually been instantiated, so it is 4000 // still okay to specialize it. 4001 StripImplicitInstantiation(PrevDecl); 4002 return false; 4003 } 4004 // Fall through 4005 4006 case TSK_ExplicitInstantiationDeclaration: 4007 case TSK_ExplicitInstantiationDefinition: 4008 assert((PrevTSK == TSK_ImplicitInstantiation || 4009 PrevPointOfInstantiation.isValid()) && 4010 "Explicit instantiation without point of instantiation?"); 4011 4012 // C++ [temp.expl.spec]p6: 4013 // If a template, a member template or the member of a class template 4014 // is explicitly specialized then that specialization shall be declared 4015 // before the first use of that specialization that would cause an 4016 // implicit instantiation to take place, in every translation unit in 4017 // which such a use occurs; no diagnostic is required. 4018 for (NamedDecl *Prev = PrevDecl; Prev; Prev = getPreviousDecl(Prev)) { 4019 // Is there any previous explicit specialization declaration? 4020 if (getTemplateSpecializationKind(Prev) == TSK_ExplicitSpecialization) 4021 return false; 4022 } 4023 4024 Diag(NewLoc, diag::err_specialization_after_instantiation) 4025 << PrevDecl; 4026 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) 4027 << (PrevTSK != TSK_ImplicitInstantiation); 4028 4029 return true; 4030 } 4031 break; 4032 4033 case TSK_ExplicitInstantiationDeclaration: 4034 switch (PrevTSK) { 4035 case TSK_ExplicitInstantiationDeclaration: 4036 // This explicit instantiation declaration is redundant (that's okay). 4037 SuppressNew = true; 4038 return false; 4039 4040 case TSK_Undeclared: 4041 case TSK_ImplicitInstantiation: 4042 // We're explicitly instantiating something that may have already been 4043 // implicitly instantiated; that's fine. 4044 return false; 4045 4046 case TSK_ExplicitSpecialization: 4047 // C++0x [temp.explicit]p4: 4048 // For a given set of template parameters, if an explicit instantiation 4049 // of a template appears after a declaration of an explicit 4050 // specialization for that template, the explicit instantiation has no 4051 // effect. 4052 SuppressNew = true; 4053 return false; 4054 4055 case TSK_ExplicitInstantiationDefinition: 4056 // C++0x [temp.explicit]p10: 4057 // If an entity is the subject of both an explicit instantiation 4058 // declaration and an explicit instantiation definition in the same 4059 // translation unit, the definition shall follow the declaration. 4060 Diag(NewLoc, 4061 diag::err_explicit_instantiation_declaration_after_definition); 4062 Diag(PrevPointOfInstantiation, 4063 diag::note_explicit_instantiation_definition_here); 4064 assert(PrevPointOfInstantiation.isValid() && 4065 "Explicit instantiation without point of instantiation?"); 4066 SuppressNew = true; 4067 return false; 4068 } 4069 break; 4070 4071 case TSK_ExplicitInstantiationDefinition: 4072 switch (PrevTSK) { 4073 case TSK_Undeclared: 4074 case TSK_ImplicitInstantiation: 4075 // We're explicitly instantiating something that may have already been 4076 // implicitly instantiated; that's fine. 4077 return false; 4078 4079 case TSK_ExplicitSpecialization: 4080 // C++ DR 259, C++0x [temp.explicit]p4: 4081 // For a given set of template parameters, if an explicit 4082 // instantiation of a template appears after a declaration of 4083 // an explicit specialization for that template, the explicit 4084 // instantiation has no effect. 4085 // 4086 // In C++98/03 mode, we only give an extension warning here, because it 4087 // is not harmful to try to explicitly instantiate something that 4088 // has been explicitly specialized. 4089 if (!getLangOptions().CPlusPlus0x) { 4090 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization) 4091 << PrevDecl; 4092 Diag(PrevDecl->getLocation(), 4093 diag::note_previous_template_specialization); 4094 } 4095 SuppressNew = true; 4096 return false; 4097 4098 case TSK_ExplicitInstantiationDeclaration: 4099 // We're explicity instantiating a definition for something for which we 4100 // were previously asked to suppress instantiations. That's fine. 4101 return false; 4102 4103 case TSK_ExplicitInstantiationDefinition: 4104 // C++0x [temp.spec]p5: 4105 // For a given template and a given set of template-arguments, 4106 // - an explicit instantiation definition shall appear at most once 4107 // in a program, 4108 Diag(NewLoc, diag::err_explicit_instantiation_duplicate) 4109 << PrevDecl; 4110 Diag(PrevPointOfInstantiation, 4111 diag::note_previous_explicit_instantiation); 4112 SuppressNew = true; 4113 return false; 4114 } 4115 break; 4116 } 4117 4118 assert(false && "Missing specialization/instantiation case?"); 4119 4120 return false; 4121} 4122 4123/// \brief Perform semantic analysis for the given dependent function 4124/// template specialization. The only possible way to get a dependent 4125/// function template specialization is with a friend declaration, 4126/// like so: 4127/// 4128/// template <class T> void foo(T); 4129/// template <class T> class A { 4130/// friend void foo<>(T); 4131/// }; 4132/// 4133/// There really isn't any useful analysis we can do here, so we 4134/// just store the information. 4135bool 4136Sema::CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD, 4137 const TemplateArgumentListInfo &ExplicitTemplateArgs, 4138 LookupResult &Previous) { 4139 // Remove anything from Previous that isn't a function template in 4140 // the correct context. 4141 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 4142 LookupResult::Filter F = Previous.makeFilter(); 4143 while (F.hasNext()) { 4144 NamedDecl *D = F.next()->getUnderlyingDecl(); 4145 if (!isa<FunctionTemplateDecl>(D) || 4146 !FDLookupContext->Equals(D->getDeclContext()->getLookupContext())) 4147 F.erase(); 4148 } 4149 F.done(); 4150 4151 // Should this be diagnosed here? 4152 if (Previous.empty()) return true; 4153 4154 FD->setDependentTemplateSpecialization(Context, Previous.asUnresolvedSet(), 4155 ExplicitTemplateArgs); 4156 return false; 4157} 4158 4159/// \brief Perform semantic analysis for the given function template 4160/// specialization. 4161/// 4162/// This routine performs all of the semantic analysis required for an 4163/// explicit function template specialization. On successful completion, 4164/// the function declaration \p FD will become a function template 4165/// specialization. 4166/// 4167/// \param FD the function declaration, which will be updated to become a 4168/// function template specialization. 4169/// 4170/// \param HasExplicitTemplateArgs whether any template arguments were 4171/// explicitly provided. 4172/// 4173/// \param LAngleLoc the location of the left angle bracket ('<'), if 4174/// template arguments were explicitly provided. 4175/// 4176/// \param ExplicitTemplateArgs the explicitly-provided template arguments, 4177/// if any. 4178/// 4179/// \param NumExplicitTemplateArgs the number of explicitly-provided template 4180/// arguments. This number may be zero even when HasExplicitTemplateArgs is 4181/// true as in, e.g., \c void sort<>(char*, char*); 4182/// 4183/// \param RAngleLoc the location of the right angle bracket ('>'), if 4184/// template arguments were explicitly provided. 4185/// 4186/// \param PrevDecl the set of declarations that 4187bool 4188Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, 4189 const TemplateArgumentListInfo *ExplicitTemplateArgs, 4190 LookupResult &Previous) { 4191 // The set of function template specializations that could match this 4192 // explicit function template specialization. 4193 UnresolvedSet<8> Candidates; 4194 4195 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 4196 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4197 I != E; ++I) { 4198 NamedDecl *Ovl = (*I)->getUnderlyingDecl(); 4199 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { 4200 // Only consider templates found within the same semantic lookup scope as 4201 // FD. 4202 if (!FDLookupContext->Equals(Ovl->getDeclContext()->getLookupContext())) 4203 continue; 4204 4205 // C++ [temp.expl.spec]p11: 4206 // A trailing template-argument can be left unspecified in the 4207 // template-id naming an explicit function template specialization 4208 // provided it can be deduced from the function argument type. 4209 // Perform template argument deduction to determine whether we may be 4210 // specializing this template. 4211 // FIXME: It is somewhat wasteful to build 4212 TemplateDeductionInfo Info(Context, FD->getLocation()); 4213 FunctionDecl *Specialization = 0; 4214 if (TemplateDeductionResult TDK 4215 = DeduceTemplateArguments(FunTmpl, ExplicitTemplateArgs, 4216 FD->getType(), 4217 Specialization, 4218 Info)) { 4219 // FIXME: Template argument deduction failed; record why it failed, so 4220 // that we can provide nifty diagnostics. 4221 (void)TDK; 4222 continue; 4223 } 4224 4225 // Record this candidate. 4226 Candidates.addDecl(Specialization, I.getAccess()); 4227 } 4228 } 4229 4230 // Find the most specialized function template. 4231 UnresolvedSetIterator Result 4232 = getMostSpecialized(Candidates.begin(), Candidates.end(), 4233 TPOC_Other, FD->getLocation(), 4234 PDiag(diag::err_function_template_spec_no_match) 4235 << FD->getDeclName(), 4236 PDiag(diag::err_function_template_spec_ambiguous) 4237 << FD->getDeclName() << (ExplicitTemplateArgs != 0), 4238 PDiag(diag::note_function_template_spec_matched)); 4239 if (Result == Candidates.end()) 4240 return true; 4241 4242 // Ignore access information; it doesn't figure into redeclaration checking. 4243 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 4244 Specialization->setLocation(FD->getLocation()); 4245 4246 // FIXME: Check if the prior specialization has a point of instantiation. 4247 // If so, we have run afoul of . 4248 4249 // If this is a friend declaration, then we're not really declaring 4250 // an explicit specialization. 4251 bool isFriend = (FD->getFriendObjectKind() != Decl::FOK_None); 4252 4253 // Check the scope of this explicit specialization. 4254 if (!isFriend && 4255 CheckTemplateSpecializationScope(*this, 4256 Specialization->getPrimaryTemplate(), 4257 Specialization, FD->getLocation(), 4258 false)) 4259 return true; 4260 4261 // C++ [temp.expl.spec]p6: 4262 // If a template, a member template or the member of a class template is 4263 // explicitly specialized then that specialization shall be declared 4264 // before the first use of that specialization that would cause an implicit 4265 // instantiation to take place, in every translation unit in which such a 4266 // use occurs; no diagnostic is required. 4267 FunctionTemplateSpecializationInfo *SpecInfo 4268 = Specialization->getTemplateSpecializationInfo(); 4269 assert(SpecInfo && "Function template specialization info missing?"); 4270 4271 bool SuppressNew = false; 4272 if (!isFriend && 4273 CheckSpecializationInstantiationRedecl(FD->getLocation(), 4274 TSK_ExplicitSpecialization, 4275 Specialization, 4276 SpecInfo->getTemplateSpecializationKind(), 4277 SpecInfo->getPointOfInstantiation(), 4278 SuppressNew)) 4279 return true; 4280 4281 // Mark the prior declaration as an explicit specialization, so that later 4282 // clients know that this is an explicit specialization. 4283 if (!isFriend) 4284 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); 4285 4286 // Turn the given function declaration into a function template 4287 // specialization, with the template arguments from the previous 4288 // specialization. 4289 FD->setFunctionTemplateSpecialization(Specialization->getPrimaryTemplate(), 4290 new (Context) TemplateArgumentList( 4291 *Specialization->getTemplateSpecializationArgs()), 4292 /*InsertPos=*/0, 4293 SpecInfo->getTemplateSpecializationKind()); 4294 4295 // The "previous declaration" for this function template specialization is 4296 // the prior function template specialization. 4297 Previous.clear(); 4298 Previous.addDecl(Specialization); 4299 return false; 4300} 4301 4302/// \brief Perform semantic analysis for the given non-template member 4303/// specialization. 4304/// 4305/// This routine performs all of the semantic analysis required for an 4306/// explicit member function specialization. On successful completion, 4307/// the function declaration \p FD will become a member function 4308/// specialization. 4309/// 4310/// \param Member the member declaration, which will be updated to become a 4311/// specialization. 4312/// 4313/// \param Previous the set of declarations, one of which may be specialized 4314/// by this function specialization; the set will be modified to contain the 4315/// redeclared member. 4316bool 4317Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { 4318 assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); 4319 4320 // Try to find the member we are instantiating. 4321 NamedDecl *Instantiation = 0; 4322 NamedDecl *InstantiatedFrom = 0; 4323 MemberSpecializationInfo *MSInfo = 0; 4324 4325 if (Previous.empty()) { 4326 // Nowhere to look anyway. 4327 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { 4328 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 4329 I != E; ++I) { 4330 NamedDecl *D = (*I)->getUnderlyingDecl(); 4331 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 4332 if (Context.hasSameType(Function->getType(), Method->getType())) { 4333 Instantiation = Method; 4334 InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); 4335 MSInfo = Method->getMemberSpecializationInfo(); 4336 break; 4337 } 4338 } 4339 } 4340 } else if (isa<VarDecl>(Member)) { 4341 VarDecl *PrevVar; 4342 if (Previous.isSingleResult() && 4343 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) 4344 if (PrevVar->isStaticDataMember()) { 4345 Instantiation = PrevVar; 4346 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); 4347 MSInfo = PrevVar->getMemberSpecializationInfo(); 4348 } 4349 } else if (isa<RecordDecl>(Member)) { 4350 CXXRecordDecl *PrevRecord; 4351 if (Previous.isSingleResult() && 4352 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { 4353 Instantiation = PrevRecord; 4354 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); 4355 MSInfo = PrevRecord->getMemberSpecializationInfo(); 4356 } 4357 } 4358 4359 if (!Instantiation) { 4360 // There is no previous declaration that matches. Since member 4361 // specializations are always out-of-line, the caller will complain about 4362 // this mismatch later. 4363 return false; 4364 } 4365 4366 // If this is a friend, just bail out here before we start turning 4367 // things into explicit specializations. 4368 if (Member->getFriendObjectKind() != Decl::FOK_None) { 4369 // Preserve instantiation information. 4370 if (InstantiatedFrom && isa<CXXMethodDecl>(Member)) { 4371 cast<CXXMethodDecl>(Member)->setInstantiationOfMemberFunction( 4372 cast<CXXMethodDecl>(InstantiatedFrom), 4373 cast<CXXMethodDecl>(Instantiation)->getTemplateSpecializationKind()); 4374 } else if (InstantiatedFrom && isa<CXXRecordDecl>(Member)) { 4375 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4376 cast<CXXRecordDecl>(InstantiatedFrom), 4377 cast<CXXRecordDecl>(Instantiation)->getTemplateSpecializationKind()); 4378 } 4379 4380 Previous.clear(); 4381 Previous.addDecl(Instantiation); 4382 return false; 4383 } 4384 4385 // Make sure that this is a specialization of a member. 4386 if (!InstantiatedFrom) { 4387 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) 4388 << Member; 4389 Diag(Instantiation->getLocation(), diag::note_specialized_decl); 4390 return true; 4391 } 4392 4393 // C++ [temp.expl.spec]p6: 4394 // If a template, a member template or the member of a class template is 4395 // explicitly specialized then that spe- cialization shall be declared 4396 // before the first use of that specialization that would cause an implicit 4397 // instantiation to take place, in every translation unit in which such a 4398 // use occurs; no diagnostic is required. 4399 assert(MSInfo && "Member specialization info missing?"); 4400 4401 bool SuppressNew = false; 4402 if (CheckSpecializationInstantiationRedecl(Member->getLocation(), 4403 TSK_ExplicitSpecialization, 4404 Instantiation, 4405 MSInfo->getTemplateSpecializationKind(), 4406 MSInfo->getPointOfInstantiation(), 4407 SuppressNew)) 4408 return true; 4409 4410 // Check the scope of this explicit specialization. 4411 if (CheckTemplateSpecializationScope(*this, 4412 InstantiatedFrom, 4413 Instantiation, Member->getLocation(), 4414 false)) 4415 return true; 4416 4417 // Note that this is an explicit instantiation of a member. 4418 // the original declaration to note that it is an explicit specialization 4419 // (if it was previously an implicit instantiation). This latter step 4420 // makes bookkeeping easier. 4421 if (isa<FunctionDecl>(Member)) { 4422 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); 4423 if (InstantiationFunction->getTemplateSpecializationKind() == 4424 TSK_ImplicitInstantiation) { 4425 InstantiationFunction->setTemplateSpecializationKind( 4426 TSK_ExplicitSpecialization); 4427 InstantiationFunction->setLocation(Member->getLocation()); 4428 } 4429 4430 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( 4431 cast<CXXMethodDecl>(InstantiatedFrom), 4432 TSK_ExplicitSpecialization); 4433 } else if (isa<VarDecl>(Member)) { 4434 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); 4435 if (InstantiationVar->getTemplateSpecializationKind() == 4436 TSK_ImplicitInstantiation) { 4437 InstantiationVar->setTemplateSpecializationKind( 4438 TSK_ExplicitSpecialization); 4439 InstantiationVar->setLocation(Member->getLocation()); 4440 } 4441 4442 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), 4443 cast<VarDecl>(InstantiatedFrom), 4444 TSK_ExplicitSpecialization); 4445 } else { 4446 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain"); 4447 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); 4448 if (InstantiationClass->getTemplateSpecializationKind() == 4449 TSK_ImplicitInstantiation) { 4450 InstantiationClass->setTemplateSpecializationKind( 4451 TSK_ExplicitSpecialization); 4452 InstantiationClass->setLocation(Member->getLocation()); 4453 } 4454 4455 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 4456 cast<CXXRecordDecl>(InstantiatedFrom), 4457 TSK_ExplicitSpecialization); 4458 } 4459 4460 // Save the caller the trouble of having to figure out which declaration 4461 // this specialization matches. 4462 Previous.clear(); 4463 Previous.addDecl(Instantiation); 4464 return false; 4465} 4466 4467/// \brief Check the scope of an explicit instantiation. 4468static void CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, 4469 SourceLocation InstLoc, 4470 bool WasQualifiedName) { 4471 DeclContext *ExpectedContext 4472 = D->getDeclContext()->getEnclosingNamespaceContext()->getLookupContext(); 4473 DeclContext *CurContext = S.CurContext->getLookupContext(); 4474 4475 // C++0x [temp.explicit]p2: 4476 // An explicit instantiation shall appear in an enclosing namespace of its 4477 // template. 4478 // 4479 // This is DR275, which we do not retroactively apply to C++98/03. 4480 if (S.getLangOptions().CPlusPlus0x && 4481 !CurContext->Encloses(ExpectedContext)) { 4482 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(ExpectedContext)) 4483 S.Diag(InstLoc, diag::err_explicit_instantiation_out_of_scope) 4484 << D << NS; 4485 else 4486 S.Diag(InstLoc, diag::err_explicit_instantiation_must_be_global) 4487 << D; 4488 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4489 return; 4490 } 4491 4492 // C++0x [temp.explicit]p2: 4493 // If the name declared in the explicit instantiation is an unqualified 4494 // name, the explicit instantiation shall appear in the namespace where 4495 // its template is declared or, if that namespace is inline (7.3.1), any 4496 // namespace from its enclosing namespace set. 4497 if (WasQualifiedName) 4498 return; 4499 4500 if (CurContext->Equals(ExpectedContext)) 4501 return; 4502 4503 S.Diag(InstLoc, diag::err_explicit_instantiation_unqualified_wrong_namespace) 4504 << D << ExpectedContext; 4505 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 4506} 4507 4508/// \brief Determine whether the given scope specifier has a template-id in it. 4509static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { 4510 if (!SS.isSet()) 4511 return false; 4512 4513 // C++0x [temp.explicit]p2: 4514 // If the explicit instantiation is for a member function, a member class 4515 // or a static data member of a class template specialization, the name of 4516 // the class template specialization in the qualified-id for the member 4517 // name shall be a simple-template-id. 4518 // 4519 // C++98 has the same restriction, just worded differently. 4520 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 4521 NNS; NNS = NNS->getPrefix()) 4522 if (Type *T = NNS->getAsType()) 4523 if (isa<TemplateSpecializationType>(T)) 4524 return true; 4525 4526 return false; 4527} 4528 4529// Explicit instantiation of a class template specialization 4530// FIXME: Implement extern template semantics 4531Sema::DeclResult 4532Sema::ActOnExplicitInstantiation(Scope *S, 4533 SourceLocation ExternLoc, 4534 SourceLocation TemplateLoc, 4535 unsigned TagSpec, 4536 SourceLocation KWLoc, 4537 const CXXScopeSpec &SS, 4538 TemplateTy TemplateD, 4539 SourceLocation TemplateNameLoc, 4540 SourceLocation LAngleLoc, 4541 ASTTemplateArgsPtr TemplateArgsIn, 4542 SourceLocation RAngleLoc, 4543 AttributeList *Attr) { 4544 // Find the class template we're specializing 4545 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 4546 ClassTemplateDecl *ClassTemplate 4547 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); 4548 4549 // Check that the specialization uses the same tag kind as the 4550 // original template. 4551 TagDecl::TagKind Kind; 4552 switch (TagSpec) { 4553 default: assert(0 && "Unknown tag type!"); 4554 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 4555 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 4556 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 4557 } 4558 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 4559 Kind, KWLoc, 4560 *ClassTemplate->getIdentifier())) { 4561 Diag(KWLoc, diag::err_use_with_wrong_tag) 4562 << ClassTemplate 4563 << FixItHint::CreateReplacement(KWLoc, 4564 ClassTemplate->getTemplatedDecl()->getKindName()); 4565 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 4566 diag::note_previous_use); 4567 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 4568 } 4569 4570 // C++0x [temp.explicit]p2: 4571 // There are two forms of explicit instantiation: an explicit instantiation 4572 // definition and an explicit instantiation declaration. An explicit 4573 // instantiation declaration begins with the extern keyword. [...] 4574 TemplateSpecializationKind TSK 4575 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4576 : TSK_ExplicitInstantiationDeclaration; 4577 4578 // Translate the parser's template argument list in our AST format. 4579 TemplateArgumentListInfo TemplateArgs(LAngleLoc, RAngleLoc); 4580 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 4581 4582 // Check that the template argument list is well-formed for this 4583 // template. 4584 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 4585 TemplateArgs.size()); 4586 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, 4587 TemplateArgs, false, Converted)) 4588 return true; 4589 4590 assert((Converted.structuredSize() == 4591 ClassTemplate->getTemplateParameters()->size()) && 4592 "Converted template argument list is too short!"); 4593 4594 // Find the class template specialization declaration that 4595 // corresponds to these arguments. 4596 llvm::FoldingSetNodeID ID; 4597 ClassTemplateSpecializationDecl::Profile(ID, 4598 Converted.getFlatArguments(), 4599 Converted.flatSize(), 4600 Context); 4601 void *InsertPos = 0; 4602 ClassTemplateSpecializationDecl *PrevDecl 4603 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 4604 4605 // C++0x [temp.explicit]p2: 4606 // [...] An explicit instantiation shall appear in an enclosing 4607 // namespace of its template. [...] 4608 // 4609 // This is C++ DR 275. 4610 CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, 4611 SS.isSet()); 4612 4613 ClassTemplateSpecializationDecl *Specialization = 0; 4614 4615 bool ReusedDecl = false; 4616 if (PrevDecl) { 4617 bool SuppressNew = false; 4618 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, 4619 PrevDecl, 4620 PrevDecl->getSpecializationKind(), 4621 PrevDecl->getPointOfInstantiation(), 4622 SuppressNew)) 4623 return DeclPtrTy::make(PrevDecl); 4624 4625 if (SuppressNew) 4626 return DeclPtrTy::make(PrevDecl); 4627 4628 if (PrevDecl->getSpecializationKind() == TSK_ImplicitInstantiation || 4629 PrevDecl->getSpecializationKind() == TSK_Undeclared) { 4630 // Since the only prior class template specialization with these 4631 // arguments was referenced but not declared, reuse that 4632 // declaration node as our own, updating its source location to 4633 // reflect our new declaration. 4634 Specialization = PrevDecl; 4635 Specialization->setLocation(TemplateNameLoc); 4636 PrevDecl = 0; 4637 ReusedDecl = true; 4638 } 4639 } 4640 4641 if (!Specialization) { 4642 // Create a new class template specialization declaration node for 4643 // this explicit specialization. 4644 Specialization 4645 = ClassTemplateSpecializationDecl::Create(Context, 4646 ClassTemplate->getDeclContext(), 4647 TemplateNameLoc, 4648 ClassTemplate, 4649 Converted, PrevDecl); 4650 SetNestedNameSpecifier(Specialization, SS); 4651 4652 if (PrevDecl) { 4653 // Remove the previous declaration from the folding set, since we want 4654 // to introduce a new declaration. 4655 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 4656 ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 4657 } 4658 4659 // Insert the new specialization. 4660 ClassTemplate->getSpecializations().InsertNode(Specialization, InsertPos); 4661 } 4662 4663 // Build the fully-sugared type for this explicit instantiation as 4664 // the user wrote in the explicit instantiation itself. This means 4665 // that we'll pretty-print the type retrieved from the 4666 // specialization's declaration the way that the user actually wrote 4667 // the explicit instantiation, rather than formatting the name based 4668 // on the "canonical" representation used to store the template 4669 // arguments in the specialization. 4670 TypeSourceInfo *WrittenTy 4671 = Context.getTemplateSpecializationTypeInfo(Name, TemplateNameLoc, 4672 TemplateArgs, 4673 Context.getTypeDeclType(Specialization)); 4674 Specialization->setTypeAsWritten(WrittenTy); 4675 TemplateArgsIn.release(); 4676 4677 if (!ReusedDecl) { 4678 // Add the explicit instantiation into its lexical context. However, 4679 // since explicit instantiations are never found by name lookup, we 4680 // just put it into the declaration context directly. 4681 Specialization->setLexicalDeclContext(CurContext); 4682 CurContext->addDecl(Specialization); 4683 } 4684 4685 // C++ [temp.explicit]p3: 4686 // A definition of a class template or class member template 4687 // shall be in scope at the point of the explicit instantiation of 4688 // the class template or class member template. 4689 // 4690 // This check comes when we actually try to perform the 4691 // instantiation. 4692 ClassTemplateSpecializationDecl *Def 4693 = cast_or_null<ClassTemplateSpecializationDecl>( 4694 Specialization->getDefinition()); 4695 if (!Def) 4696 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); 4697 4698 // Instantiate the members of this class template specialization. 4699 Def = cast_or_null<ClassTemplateSpecializationDecl>( 4700 Specialization->getDefinition()); 4701 if (Def) { 4702 TemplateSpecializationKind Old_TSK = Def->getTemplateSpecializationKind(); 4703 4704 // Fix a TSK_ExplicitInstantiationDeclaration followed by a 4705 // TSK_ExplicitInstantiationDefinition 4706 if (Old_TSK == TSK_ExplicitInstantiationDeclaration && 4707 TSK == TSK_ExplicitInstantiationDefinition) 4708 Def->setTemplateSpecializationKind(TSK); 4709 4710 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); 4711 } 4712 4713 return DeclPtrTy::make(Specialization); 4714} 4715 4716// Explicit instantiation of a member class of a class template. 4717Sema::DeclResult 4718Sema::ActOnExplicitInstantiation(Scope *S, 4719 SourceLocation ExternLoc, 4720 SourceLocation TemplateLoc, 4721 unsigned TagSpec, 4722 SourceLocation KWLoc, 4723 CXXScopeSpec &SS, 4724 IdentifierInfo *Name, 4725 SourceLocation NameLoc, 4726 AttributeList *Attr) { 4727 4728 bool Owned = false; 4729 bool IsDependent = false; 4730 DeclPtrTy TagD = ActOnTag(S, TagSpec, Action::TUK_Reference, 4731 KWLoc, SS, Name, NameLoc, Attr, AS_none, 4732 MultiTemplateParamsArg(*this, 0, 0), 4733 Owned, IsDependent); 4734 assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); 4735 4736 if (!TagD) 4737 return true; 4738 4739 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4740 if (Tag->isEnum()) { 4741 Diag(TemplateLoc, diag::err_explicit_instantiation_enum) 4742 << Context.getTypeDeclType(Tag); 4743 return true; 4744 } 4745 4746 if (Tag->isInvalidDecl()) 4747 return true; 4748 4749 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); 4750 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); 4751 if (!Pattern) { 4752 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) 4753 << Context.getTypeDeclType(Record); 4754 Diag(Record->getLocation(), diag::note_nontemplate_decl_here); 4755 return true; 4756 } 4757 4758 // C++0x [temp.explicit]p2: 4759 // If the explicit instantiation is for a class or member class, the 4760 // elaborated-type-specifier in the declaration shall include a 4761 // simple-template-id. 4762 // 4763 // C++98 has the same restriction, just worded differently. 4764 if (!ScopeSpecifierHasTemplateId(SS)) 4765 Diag(TemplateLoc, diag::err_explicit_instantiation_without_qualified_id) 4766 << Record << SS.getRange(); 4767 4768 // C++0x [temp.explicit]p2: 4769 // There are two forms of explicit instantiation: an explicit instantiation 4770 // definition and an explicit instantiation declaration. An explicit 4771 // instantiation declaration begins with the extern keyword. [...] 4772 TemplateSpecializationKind TSK 4773 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4774 : TSK_ExplicitInstantiationDeclaration; 4775 4776 // C++0x [temp.explicit]p2: 4777 // [...] An explicit instantiation shall appear in an enclosing 4778 // namespace of its template. [...] 4779 // 4780 // This is C++ DR 275. 4781 CheckExplicitInstantiationScope(*this, Record, NameLoc, true); 4782 4783 // Verify that it is okay to explicitly instantiate here. 4784 CXXRecordDecl *PrevDecl 4785 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration()); 4786 if (!PrevDecl && Record->getDefinition()) 4787 PrevDecl = Record; 4788 if (PrevDecl) { 4789 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); 4790 bool SuppressNew = false; 4791 assert(MSInfo && "No member specialization information?"); 4792 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, 4793 PrevDecl, 4794 MSInfo->getTemplateSpecializationKind(), 4795 MSInfo->getPointOfInstantiation(), 4796 SuppressNew)) 4797 return true; 4798 if (SuppressNew) 4799 return TagD; 4800 } 4801 4802 CXXRecordDecl *RecordDef 4803 = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4804 if (!RecordDef) { 4805 // C++ [temp.explicit]p3: 4806 // A definition of a member class of a class template shall be in scope 4807 // at the point of an explicit instantiation of the member class. 4808 CXXRecordDecl *Def 4809 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition()); 4810 if (!Def) { 4811 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) 4812 << 0 << Record->getDeclName() << Record->getDeclContext(); 4813 Diag(Pattern->getLocation(), diag::note_forward_declaration) 4814 << Pattern; 4815 return true; 4816 } else { 4817 if (InstantiateClass(NameLoc, Record, Def, 4818 getTemplateInstantiationArgs(Record), 4819 TSK)) 4820 return true; 4821 4822 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition()); 4823 if (!RecordDef) 4824 return true; 4825 } 4826 } 4827 4828 // Instantiate all of the members of the class. 4829 InstantiateClassMembers(NameLoc, RecordDef, 4830 getTemplateInstantiationArgs(Record), TSK); 4831 4832 // FIXME: We don't have any representation for explicit instantiations of 4833 // member classes. Such a representation is not needed for compilation, but it 4834 // should be available for clients that want to see all of the declarations in 4835 // the source code. 4836 return TagD; 4837} 4838 4839Sema::DeclResult Sema::ActOnExplicitInstantiation(Scope *S, 4840 SourceLocation ExternLoc, 4841 SourceLocation TemplateLoc, 4842 Declarator &D) { 4843 // Explicit instantiations always require a name. 4844 DeclarationName Name = GetNameForDeclarator(D); 4845 if (!Name) { 4846 if (!D.isInvalidType()) 4847 Diag(D.getDeclSpec().getSourceRange().getBegin(), 4848 diag::err_explicit_instantiation_requires_name) 4849 << D.getDeclSpec().getSourceRange() 4850 << D.getSourceRange(); 4851 4852 return true; 4853 } 4854 4855 // The scope passed in may not be a decl scope. Zip up the scope tree until 4856 // we find one that is. 4857 while ((S->getFlags() & Scope::DeclScope) == 0 || 4858 (S->getFlags() & Scope::TemplateParamScope) != 0) 4859 S = S->getParent(); 4860 4861 // Determine the type of the declaration. 4862 QualType R = GetTypeForDeclarator(D, S, 0); 4863 if (R.isNull()) 4864 return true; 4865 4866 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 4867 // Cannot explicitly instantiate a typedef. 4868 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) 4869 << Name; 4870 return true; 4871 } 4872 4873 // C++0x [temp.explicit]p1: 4874 // [...] An explicit instantiation of a function template shall not use the 4875 // inline or constexpr specifiers. 4876 // Presumably, this also applies to member functions of class templates as 4877 // well. 4878 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x) 4879 Diag(D.getDeclSpec().getInlineSpecLoc(), 4880 diag::err_explicit_instantiation_inline) 4881 <<FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 4882 4883 // FIXME: check for constexpr specifier. 4884 4885 // C++0x [temp.explicit]p2: 4886 // There are two forms of explicit instantiation: an explicit instantiation 4887 // definition and an explicit instantiation declaration. An explicit 4888 // instantiation declaration begins with the extern keyword. [...] 4889 TemplateSpecializationKind TSK 4890 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4891 : TSK_ExplicitInstantiationDeclaration; 4892 4893 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName); 4894 LookupParsedName(Previous, S, &D.getCXXScopeSpec()); 4895 4896 if (!R->isFunctionType()) { 4897 // C++ [temp.explicit]p1: 4898 // A [...] static data member of a class template can be explicitly 4899 // instantiated from the member definition associated with its class 4900 // template. 4901 if (Previous.isAmbiguous()) 4902 return true; 4903 4904 VarDecl *Prev = Previous.getAsSingle<VarDecl>(); 4905 if (!Prev || !Prev->isStaticDataMember()) { 4906 // We expect to see a data data member here. 4907 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) 4908 << Name; 4909 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 4910 P != PEnd; ++P) 4911 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); 4912 return true; 4913 } 4914 4915 if (!Prev->getInstantiatedFromStaticDataMember()) { 4916 // FIXME: Check for explicit specialization? 4917 Diag(D.getIdentifierLoc(), 4918 diag::err_explicit_instantiation_data_member_not_instantiated) 4919 << Prev; 4920 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); 4921 // FIXME: Can we provide a note showing where this was declared? 4922 return true; 4923 } 4924 4925 // C++0x [temp.explicit]p2: 4926 // If the explicit instantiation is for a member function, a member class 4927 // or a static data member of a class template specialization, the name of 4928 // the class template specialization in the qualified-id for the member 4929 // name shall be a simple-template-id. 4930 // 4931 // C++98 has the same restriction, just worded differently. 4932 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 4933 Diag(D.getIdentifierLoc(), 4934 diag::err_explicit_instantiation_without_qualified_id) 4935 << Prev << D.getCXXScopeSpec().getRange(); 4936 4937 // Check the scope of this explicit instantiation. 4938 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); 4939 4940 // Verify that it is okay to explicitly instantiate here. 4941 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); 4942 assert(MSInfo && "Missing static data member specialization info?"); 4943 bool SuppressNew = false; 4944 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, 4945 MSInfo->getTemplateSpecializationKind(), 4946 MSInfo->getPointOfInstantiation(), 4947 SuppressNew)) 4948 return true; 4949 if (SuppressNew) 4950 return DeclPtrTy(); 4951 4952 // Instantiate static data member. 4953 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 4954 if (TSK == TSK_ExplicitInstantiationDefinition) 4955 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev, false, 4956 /*DefinitionRequired=*/true); 4957 4958 // FIXME: Create an ExplicitInstantiation node? 4959 return DeclPtrTy(); 4960 } 4961 4962 // If the declarator is a template-id, translate the parser's template 4963 // argument list into our AST format. 4964 bool HasExplicitTemplateArgs = false; 4965 TemplateArgumentListInfo TemplateArgs; 4966 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4967 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4968 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4969 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4970 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4971 TemplateId->getTemplateArgs(), 4972 TemplateId->NumArgs); 4973 translateTemplateArguments(TemplateArgsPtr, TemplateArgs); 4974 HasExplicitTemplateArgs = true; 4975 TemplateArgsPtr.release(); 4976 } 4977 4978 // C++ [temp.explicit]p1: 4979 // A [...] function [...] can be explicitly instantiated from its template. 4980 // A member function [...] of a class template can be explicitly 4981 // instantiated from the member definition associated with its class 4982 // template. 4983 UnresolvedSet<8> Matches; 4984 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 4985 P != PEnd; ++P) { 4986 NamedDecl *Prev = *P; 4987 if (!HasExplicitTemplateArgs) { 4988 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { 4989 if (Context.hasSameUnqualifiedType(Method->getType(), R)) { 4990 Matches.clear(); 4991 4992 Matches.addDecl(Method, P.getAccess()); 4993 if (Method->getTemplateSpecializationKind() == TSK_Undeclared) 4994 break; 4995 } 4996 } 4997 } 4998 4999 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); 5000 if (!FunTmpl) 5001 continue; 5002 5003 TemplateDeductionInfo Info(Context, D.getIdentifierLoc()); 5004 FunctionDecl *Specialization = 0; 5005 if (TemplateDeductionResult TDK 5006 = DeduceTemplateArguments(FunTmpl, 5007 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 5008 R, Specialization, Info)) { 5009 // FIXME: Keep track of almost-matches? 5010 (void)TDK; 5011 continue; 5012 } 5013 5014 Matches.addDecl(Specialization, P.getAccess()); 5015 } 5016 5017 // Find the most specialized function template specialization. 5018 UnresolvedSetIterator Result 5019 = getMostSpecialized(Matches.begin(), Matches.end(), TPOC_Other, 5020 D.getIdentifierLoc(), 5021 PDiag(diag::err_explicit_instantiation_not_known) << Name, 5022 PDiag(diag::err_explicit_instantiation_ambiguous) << Name, 5023 PDiag(diag::note_explicit_instantiation_candidate)); 5024 5025 if (Result == Matches.end()) 5026 return true; 5027 5028 // Ignore access control bits, we don't need them for redeclaration checking. 5029 FunctionDecl *Specialization = cast<FunctionDecl>(*Result); 5030 5031 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { 5032 Diag(D.getIdentifierLoc(), 5033 diag::err_explicit_instantiation_member_function_not_instantiated) 5034 << Specialization 5035 << (Specialization->getTemplateSpecializationKind() == 5036 TSK_ExplicitSpecialization); 5037 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); 5038 return true; 5039 } 5040 5041 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration(); 5042 if (!PrevDecl && Specialization->isThisDeclarationADefinition()) 5043 PrevDecl = Specialization; 5044 5045 if (PrevDecl) { 5046 bool SuppressNew = false; 5047 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, 5048 PrevDecl, 5049 PrevDecl->getTemplateSpecializationKind(), 5050 PrevDecl->getPointOfInstantiation(), 5051 SuppressNew)) 5052 return true; 5053 5054 // FIXME: We may still want to build some representation of this 5055 // explicit specialization. 5056 if (SuppressNew) 5057 return DeclPtrTy(); 5058 } 5059 5060 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 5061 5062 if (TSK == TSK_ExplicitInstantiationDefinition) 5063 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization, 5064 false, /*DefinitionRequired=*/true); 5065 5066 // C++0x [temp.explicit]p2: 5067 // If the explicit instantiation is for a member function, a member class 5068 // or a static data member of a class template specialization, the name of 5069 // the class template specialization in the qualified-id for the member 5070 // name shall be a simple-template-id. 5071 // 5072 // C++98 has the same restriction, just worded differently. 5073 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); 5074 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && 5075 D.getCXXScopeSpec().isSet() && 5076 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 5077 Diag(D.getIdentifierLoc(), 5078 diag::err_explicit_instantiation_without_qualified_id) 5079 << Specialization << D.getCXXScopeSpec().getRange(); 5080 5081 CheckExplicitInstantiationScope(*this, 5082 FunTmpl? (NamedDecl *)FunTmpl 5083 : Specialization->getInstantiatedFromMemberFunction(), 5084 D.getIdentifierLoc(), 5085 D.getCXXScopeSpec().isSet()); 5086 5087 // FIXME: Create some kind of ExplicitInstantiationDecl here. 5088 return DeclPtrTy(); 5089} 5090 5091Sema::TypeResult 5092Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5093 const CXXScopeSpec &SS, IdentifierInfo *Name, 5094 SourceLocation TagLoc, SourceLocation NameLoc) { 5095 // This has to hold, because SS is expected to be defined. 5096 assert(Name && "Expected a name in a dependent tag"); 5097 5098 NestedNameSpecifier *NNS 5099 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5100 if (!NNS) 5101 return true; 5102 5103 ElaboratedTypeKeyword Keyword = ETK_None; 5104 switch (TagDecl::getTagKindForTypeSpec(TagSpec)) { 5105 case TagDecl::TK_struct: Keyword = ETK_Struct; break; 5106 case TagDecl::TK_class: Keyword = ETK_Class; break; 5107 case TagDecl::TK_union: Keyword = ETK_Union; break; 5108 case TagDecl::TK_enum: Keyword = ETK_Enum; break; 5109 } 5110 assert(Keyword != ETK_None && "Invalid tag kind!"); 5111 5112 return Context.getDependentNameType(Keyword, NNS, Name).getAsOpaquePtr(); 5113} 5114 5115Sema::TypeResult 5116Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS, 5117 const IdentifierInfo &II, SourceLocation IdLoc) { 5118 NestedNameSpecifier *NNS 5119 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5120 if (!NNS) 5121 return true; 5122 5123 QualType T = CheckTypenameType(NNS, II, SourceRange(TypenameLoc, IdLoc)); 5124 if (T.isNull()) 5125 return true; 5126 return T.getAsOpaquePtr(); 5127} 5128 5129Sema::TypeResult 5130Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS, 5131 SourceLocation TemplateLoc, TypeTy *Ty) { 5132 QualType T = GetTypeFromParser(Ty); 5133 NestedNameSpecifier *NNS 5134 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 5135 const TemplateSpecializationType *TemplateId 5136 = T->getAs<TemplateSpecializationType>(); 5137 assert(TemplateId && "Expected a template specialization type"); 5138 5139 if (computeDeclContext(SS, false)) { 5140 // If we can compute a declaration context, then the "typename" 5141 // keyword was superfluous. Just build a QualifiedNameType to keep 5142 // track of the nested-name-specifier. 5143 5144 // FIXME: Note that the QualifiedNameType had the "typename" keyword! 5145 return Context.getQualifiedNameType(NNS, T).getAsOpaquePtr(); 5146 } 5147 5148 return Context.getDependentNameType(ETK_Typename, NNS, TemplateId) 5149 .getAsOpaquePtr(); 5150} 5151 5152/// \brief Build the type that describes a C++ typename specifier, 5153/// e.g., "typename T::type". 5154QualType 5155Sema::CheckTypenameType(NestedNameSpecifier *NNS, const IdentifierInfo &II, 5156 SourceRange Range) { 5157 CXXRecordDecl *CurrentInstantiation = 0; 5158 if (NNS->isDependent()) { 5159 CurrentInstantiation = getCurrentInstantiationOf(NNS); 5160 5161 // If the nested-name-specifier does not refer to the current 5162 // instantiation, then build a typename type. 5163 if (!CurrentInstantiation) 5164 return Context.getDependentNameType(ETK_Typename, NNS, &II); 5165 5166 // The nested-name-specifier refers to the current instantiation, so the 5167 // "typename" keyword itself is superfluous. In C++03, the program is 5168 // actually ill-formed. However, DR 382 (in C++0x CD1) allows such 5169 // extraneous "typename" keywords, and we retroactively apply this DR to 5170 // C++03 code. 5171 } 5172 5173 DeclContext *Ctx = 0; 5174 5175 if (CurrentInstantiation) 5176 Ctx = CurrentInstantiation; 5177 else { 5178 CXXScopeSpec SS; 5179 SS.setScopeRep(NNS); 5180 SS.setRange(Range); 5181 if (RequireCompleteDeclContext(SS)) 5182 return QualType(); 5183 5184 Ctx = computeDeclContext(SS); 5185 } 5186 assert(Ctx && "No declaration context?"); 5187 5188 DeclarationName Name(&II); 5189 LookupResult Result(*this, Name, Range.getEnd(), LookupOrdinaryName); 5190 LookupQualifiedName(Result, Ctx); 5191 unsigned DiagID = 0; 5192 Decl *Referenced = 0; 5193 switch (Result.getResultKind()) { 5194 case LookupResult::NotFound: 5195 DiagID = diag::err_typename_nested_not_found; 5196 break; 5197 5198 case LookupResult::NotFoundInCurrentInstantiation: 5199 // Okay, it's a member of an unknown instantiation. 5200 return Context.getDependentNameType(ETK_Typename, NNS, &II); 5201 5202 case LookupResult::Found: 5203 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { 5204 // We found a type. Build a QualifiedNameType, since the 5205 // typename-specifier was just sugar. FIXME: Tell 5206 // QualifiedNameType that it has a "typename" prefix. 5207 return Context.getQualifiedNameType(NNS, Context.getTypeDeclType(Type)); 5208 } 5209 5210 DiagID = diag::err_typename_nested_not_type; 5211 Referenced = Result.getFoundDecl(); 5212 break; 5213 5214 case LookupResult::FoundUnresolvedValue: 5215 llvm_unreachable("unresolved using decl in non-dependent context"); 5216 return QualType(); 5217 5218 case LookupResult::FoundOverloaded: 5219 DiagID = diag::err_typename_nested_not_type; 5220 Referenced = *Result.begin(); 5221 break; 5222 5223 case LookupResult::Ambiguous: 5224 return QualType(); 5225 } 5226 5227 // If we get here, it's because name lookup did not find a 5228 // type. Emit an appropriate diagnostic and return an error. 5229 Diag(Range.getEnd(), DiagID) << Range << Name << Ctx; 5230 if (Referenced) 5231 Diag(Referenced->getLocation(), diag::note_typename_refers_here) 5232 << Name; 5233 return QualType(); 5234} 5235 5236namespace { 5237 // See Sema::RebuildTypeInCurrentInstantiation 5238 class CurrentInstantiationRebuilder 5239 : public TreeTransform<CurrentInstantiationRebuilder> { 5240 SourceLocation Loc; 5241 DeclarationName Entity; 5242 5243 public: 5244 CurrentInstantiationRebuilder(Sema &SemaRef, 5245 SourceLocation Loc, 5246 DeclarationName Entity) 5247 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), 5248 Loc(Loc), Entity(Entity) { } 5249 5250 /// \brief Determine whether the given type \p T has already been 5251 /// transformed. 5252 /// 5253 /// For the purposes of type reconstruction, a type has already been 5254 /// transformed if it is NULL or if it is not dependent. 5255 bool AlreadyTransformed(QualType T) { 5256 return T.isNull() || !T->isDependentType(); 5257 } 5258 5259 /// \brief Returns the location of the entity whose type is being 5260 /// rebuilt. 5261 SourceLocation getBaseLocation() { return Loc; } 5262 5263 /// \brief Returns the name of the entity whose type is being rebuilt. 5264 DeclarationName getBaseEntity() { return Entity; } 5265 5266 /// \brief Sets the "base" location and entity when that 5267 /// information is known based on another transformation. 5268 void setBase(SourceLocation Loc, DeclarationName Entity) { 5269 this->Loc = Loc; 5270 this->Entity = Entity; 5271 } 5272 5273 /// \brief Transforms an expression by returning the expression itself 5274 /// (an identity function). 5275 /// 5276 /// FIXME: This is completely unsafe; we will need to actually clone the 5277 /// expressions. 5278 Sema::OwningExprResult TransformExpr(Expr *E) { 5279 return getSema().Owned(E); 5280 } 5281 5282 /// \brief Transforms a typename type by determining whether the type now 5283 /// refers to a member of the current instantiation, and then 5284 /// type-checking and building a QualifiedNameType (when possible). 5285 QualType TransformDependentNameType(TypeLocBuilder &TLB, DependentNameTypeLoc TL, 5286 QualType ObjectType); 5287 }; 5288} 5289 5290QualType 5291CurrentInstantiationRebuilder::TransformDependentNameType(TypeLocBuilder &TLB, 5292 DependentNameTypeLoc TL, 5293 QualType ObjectType) { 5294 DependentNameType *T = TL.getTypePtr(); 5295 5296 NestedNameSpecifier *NNS 5297 = TransformNestedNameSpecifier(T->getQualifier(), 5298 /*FIXME:*/SourceRange(getBaseLocation()), 5299 ObjectType); 5300 if (!NNS) 5301 return QualType(); 5302 5303 // If the nested-name-specifier did not change, and we cannot compute the 5304 // context corresponding to the nested-name-specifier, then this 5305 // typename type will not change; exit early. 5306 CXXScopeSpec SS; 5307 SS.setRange(SourceRange(getBaseLocation())); 5308 SS.setScopeRep(NNS); 5309 5310 QualType Result; 5311 if (NNS == T->getQualifier() && getSema().computeDeclContext(SS) == 0) 5312 Result = QualType(T, 0); 5313 5314 // Rebuild the typename type, which will probably turn into a 5315 // QualifiedNameType. 5316 else if (const TemplateSpecializationType *TemplateId = T->getTemplateId()) { 5317 QualType NewTemplateId 5318 = TransformType(QualType(TemplateId, 0)); 5319 if (NewTemplateId.isNull()) 5320 return QualType(); 5321 5322 if (NNS == T->getQualifier() && 5323 NewTemplateId == QualType(TemplateId, 0)) 5324 Result = QualType(T, 0); 5325 else 5326 Result = getDerived().RebuildDependentNameType(T->getKeyword(), 5327 NNS, NewTemplateId); 5328 } else 5329 Result = getDerived().RebuildDependentNameType(T->getKeyword(), 5330 NNS, T->getIdentifier(), 5331 SourceRange(TL.getNameLoc())); 5332 5333 if (Result.isNull()) 5334 return QualType(); 5335 5336 DependentNameTypeLoc NewTL = TLB.push<DependentNameTypeLoc>(Result); 5337 NewTL.setNameLoc(TL.getNameLoc()); 5338 return Result; 5339} 5340 5341/// \brief Rebuilds a type within the context of the current instantiation. 5342/// 5343/// The type \p T is part of the type of an out-of-line member definition of 5344/// a class template (or class template partial specialization) that was parsed 5345/// and constructed before we entered the scope of the class template (or 5346/// partial specialization thereof). This routine will rebuild that type now 5347/// that we have entered the declarator's scope, which may produce different 5348/// canonical types, e.g., 5349/// 5350/// \code 5351/// template<typename T> 5352/// struct X { 5353/// typedef T* pointer; 5354/// pointer data(); 5355/// }; 5356/// 5357/// template<typename T> 5358/// typename X<T>::pointer X<T>::data() { ... } 5359/// \endcode 5360/// 5361/// Here, the type "typename X<T>::pointer" will be created as a DependentNameType, 5362/// since we do not know that we can look into X<T> when we parsed the type. 5363/// This function will rebuild the type, performing the lookup of "pointer" 5364/// in X<T> and returning a QualifiedNameType whose canonical type is the same 5365/// as the canonical type of T*, allowing the return types of the out-of-line 5366/// definition and the declaration to match. 5367QualType Sema::RebuildTypeInCurrentInstantiation(QualType T, SourceLocation Loc, 5368 DeclarationName Name) { 5369 if (T.isNull() || !T->isDependentType()) 5370 return T; 5371 5372 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); 5373 return Rebuilder.TransformType(T); 5374} 5375 5376/// \brief Produces a formatted string that describes the binding of 5377/// template parameters to template arguments. 5378std::string 5379Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5380 const TemplateArgumentList &Args) { 5381 // FIXME: For variadic templates, we'll need to get the structured list. 5382 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(), 5383 Args.flat_size()); 5384} 5385 5386std::string 5387Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 5388 const TemplateArgument *Args, 5389 unsigned NumArgs) { 5390 std::string Result; 5391 5392 if (!Params || Params->size() == 0 || NumArgs == 0) 5393 return Result; 5394 5395 for (unsigned I = 0, N = Params->size(); I != N; ++I) { 5396 if (I >= NumArgs) 5397 break; 5398 5399 if (I == 0) 5400 Result += "[with "; 5401 else 5402 Result += ", "; 5403 5404 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { 5405 Result += Id->getName(); 5406 } else { 5407 Result += '$'; 5408 Result += llvm::utostr(I); 5409 } 5410 5411 Result += " = "; 5412 5413 switch (Args[I].getKind()) { 5414 case TemplateArgument::Null: 5415 Result += "<no value>"; 5416 break; 5417 5418 case TemplateArgument::Type: { 5419 std::string TypeStr; 5420 Args[I].getAsType().getAsStringInternal(TypeStr, 5421 Context.PrintingPolicy); 5422 Result += TypeStr; 5423 break; 5424 } 5425 5426 case TemplateArgument::Declaration: { 5427 bool Unnamed = true; 5428 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) { 5429 if (ND->getDeclName()) { 5430 Unnamed = false; 5431 Result += ND->getNameAsString(); 5432 } 5433 } 5434 5435 if (Unnamed) { 5436 Result += "<anonymous>"; 5437 } 5438 break; 5439 } 5440 5441 case TemplateArgument::Template: { 5442 std::string Str; 5443 llvm::raw_string_ostream OS(Str); 5444 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy); 5445 Result += OS.str(); 5446 break; 5447 } 5448 5449 case TemplateArgument::Integral: { 5450 Result += Args[I].getAsIntegral()->toString(10); 5451 break; 5452 } 5453 5454 case TemplateArgument::Expression: { 5455 assert(false && "No expressions in deduced template arguments!"); 5456 Result += "<expression>"; 5457 break; 5458 } 5459 5460 case TemplateArgument::Pack: 5461 // FIXME: Format template argument packs 5462 Result += "<template argument pack>"; 5463 break; 5464 } 5465 } 5466 5467 Result += ']'; 5468 return Result; 5469} 5470