SemaTemplate.cpp revision 1c23b3ff07ff44e67f0bbc0cc55e2268da57912f
1//===------- SemaTemplate.cpp - Semantic Analysis for C++ Templates -------===/ 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7//===----------------------------------------------------------------------===/ 8// 9// This file implements semantic analysis for C++ templates. 10//===----------------------------------------------------------------------===/ 11 12#include "Sema.h" 13#include "Lookup.h" 14#include "TreeTransform.h" 15#include "clang/AST/ASTContext.h" 16#include "clang/AST/Expr.h" 17#include "clang/AST/ExprCXX.h" 18#include "clang/AST/DeclTemplate.h" 19#include "clang/Parse/DeclSpec.h" 20#include "clang/Parse/Template.h" 21#include "clang/Basic/LangOptions.h" 22#include "clang/Basic/PartialDiagnostic.h" 23#include "llvm/Support/Compiler.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 OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D); 63 if (!Ovl) 64 return 0; 65 66 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 67 FEnd = Ovl->function_end(); 68 F != FEnd; ++F) { 69 if (FunctionTemplateDecl *FuncTmpl = dyn_cast<FunctionTemplateDecl>(*F)) { 70 // We've found a function template. Determine whether there are 71 // any other function templates we need to bundle together in an 72 // OverloadedFunctionDecl 73 for (++F; F != FEnd; ++F) { 74 if (isa<FunctionTemplateDecl>(*F)) 75 break; 76 } 77 78 if (F != FEnd) { 79 // Build an overloaded function decl containing only the 80 // function templates in Ovl. 81 OverloadedFunctionDecl *OvlTemplate 82 = OverloadedFunctionDecl::Create(Context, 83 Ovl->getDeclContext(), 84 Ovl->getDeclName()); 85 OvlTemplate->addOverload(FuncTmpl); 86 OvlTemplate->addOverload(*F); 87 for (++F; F != FEnd; ++F) { 88 if (isa<FunctionTemplateDecl>(*F)) 89 OvlTemplate->addOverload(*F); 90 } 91 92 return OvlTemplate; 93 } 94 95 return FuncTmpl; 96 } 97 } 98 99 return 0; 100} 101 102TemplateNameKind Sema::isTemplateName(Scope *S, 103 const CXXScopeSpec &SS, 104 UnqualifiedId &Name, 105 TypeTy *ObjectTypePtr, 106 bool EnteringContext, 107 TemplateTy &TemplateResult) { 108 DeclarationName TName; 109 110 switch (Name.getKind()) { 111 case UnqualifiedId::IK_Identifier: 112 TName = DeclarationName(Name.Identifier); 113 break; 114 115 case UnqualifiedId::IK_OperatorFunctionId: 116 TName = Context.DeclarationNames.getCXXOperatorName( 117 Name.OperatorFunctionId.Operator); 118 break; 119 120 default: 121 return TNK_Non_template; 122 } 123 124 // Determine where to perform name lookup 125 DeclContext *LookupCtx = 0; 126 bool isDependent = false; 127 if (ObjectTypePtr) { 128 // This nested-name-specifier occurs in a member access expression, e.g., 129 // x->B::f, and we are looking into the type of the object. 130 assert(!SS.isSet() && "ObjectType and scope specifier cannot coexist"); 131 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 132 LookupCtx = computeDeclContext(ObjectType); 133 isDependent = ObjectType->isDependentType(); 134 assert((isDependent || !ObjectType->isIncompleteType()) && 135 "Caller should have completed object type"); 136 } else if (SS.isSet()) { 137 // This nested-name-specifier occurs after another nested-name-specifier, 138 // so long into the context associated with the prior nested-name-specifier. 139 LookupCtx = computeDeclContext(SS, EnteringContext); 140 isDependent = isDependentScopeSpecifier(SS); 141 142 // The declaration context must be complete. 143 if (LookupCtx && RequireCompleteDeclContext(SS)) 144 return TNK_Non_template; 145 } 146 147 LookupResult Found(*this, TName, SourceLocation(), LookupOrdinaryName); 148 bool ObjectTypeSearchedInScope = false; 149 if (LookupCtx) { 150 // Perform "qualified" name lookup into the declaration context we 151 // computed, which is either the type of the base of a member access 152 // expression or the declaration context associated with a prior 153 // nested-name-specifier. 154 LookupQualifiedName(Found, LookupCtx); 155 156 if (ObjectTypePtr && Found.empty()) { 157 // C++ [basic.lookup.classref]p1: 158 // In a class member access expression (5.2.5), if the . or -> token is 159 // immediately followed by an identifier followed by a <, the 160 // identifier must be looked up to determine whether the < is the 161 // beginning of a template argument list (14.2) or a less-than operator. 162 // The identifier is first looked up in the class of the object 163 // expression. If the identifier is not found, it is then looked up in 164 // the context of the entire postfix-expression and shall name a class 165 // or function template. 166 // 167 // FIXME: When we're instantiating a template, do we actually have to 168 // look in the scope of the template? Seems fishy... 169 LookupName(Found, S); 170 ObjectTypeSearchedInScope = true; 171 } 172 } else if (isDependent) { 173 // We cannot look into a dependent object type or 174 return TNK_Non_template; 175 } else { 176 // Perform unqualified name lookup in the current scope. 177 LookupName(Found, S); 178 } 179 180 // FIXME: Cope with ambiguous name-lookup results. 181 assert(!Found.isAmbiguous() && 182 "Cannot handle template name-lookup ambiguities"); 183 184 NamedDecl *Template 185 = isAcceptableTemplateName(Context, Found.getAsSingleDecl(Context)); 186 if (!Template) 187 return TNK_Non_template; 188 189 if (ObjectTypePtr && !ObjectTypeSearchedInScope) { 190 // C++ [basic.lookup.classref]p1: 191 // [...] If the lookup in the class of the object expression finds a 192 // template, the name is also looked up in the context of the entire 193 // postfix-expression and [...] 194 // 195 LookupResult FoundOuter(*this, TName, SourceLocation(), LookupOrdinaryName); 196 LookupName(FoundOuter, S); 197 // FIXME: Handle ambiguities in this lookup better 198 NamedDecl *OuterTemplate 199 = isAcceptableTemplateName(Context, FoundOuter.getAsSingleDecl(Context)); 200 201 if (!OuterTemplate) { 202 // - if the name is not found, the name found in the class of the 203 // object expression is used, otherwise 204 } else if (!isa<ClassTemplateDecl>(OuterTemplate)) { 205 // - if the name is found in the context of the entire 206 // postfix-expression and does not name a class template, the name 207 // found in the class of the object expression is used, otherwise 208 } else { 209 // - if the name found is a class template, it must refer to the same 210 // entity as the one found in the class of the object expression, 211 // otherwise the program is ill-formed. 212 if (OuterTemplate->getCanonicalDecl() != Template->getCanonicalDecl()) { 213 Diag(Name.getSourceRange().getBegin(), 214 diag::err_nested_name_member_ref_lookup_ambiguous) 215 << TName 216 << Name.getSourceRange(); 217 Diag(Template->getLocation(), diag::note_ambig_member_ref_object_type) 218 << QualType::getFromOpaquePtr(ObjectTypePtr); 219 Diag(OuterTemplate->getLocation(), diag::note_ambig_member_ref_scope); 220 221 // Recover by taking the template that we found in the object 222 // expression's type. 223 } 224 } 225 } 226 227 if (SS.isSet() && !SS.isInvalid()) { 228 NestedNameSpecifier *Qualifier 229 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 230 if (OverloadedFunctionDecl *Ovl 231 = dyn_cast<OverloadedFunctionDecl>(Template)) 232 TemplateResult 233 = TemplateTy::make(Context.getQualifiedTemplateName(Qualifier, false, 234 Ovl)); 235 else 236 TemplateResult 237 = TemplateTy::make(Context.getQualifiedTemplateName(Qualifier, false, 238 cast<TemplateDecl>(Template))); 239 } else if (OverloadedFunctionDecl *Ovl 240 = dyn_cast<OverloadedFunctionDecl>(Template)) { 241 TemplateResult = TemplateTy::make(TemplateName(Ovl)); 242 } else { 243 TemplateResult = TemplateTy::make( 244 TemplateName(cast<TemplateDecl>(Template))); 245 } 246 247 if (isa<ClassTemplateDecl>(Template) || 248 isa<TemplateTemplateParmDecl>(Template)) 249 return TNK_Type_template; 250 251 assert((isa<FunctionTemplateDecl>(Template) || 252 isa<OverloadedFunctionDecl>(Template)) && 253 "Unhandled template kind in Sema::isTemplateName"); 254 return TNK_Function_template; 255} 256 257/// DiagnoseTemplateParameterShadow - Produce a diagnostic complaining 258/// that the template parameter 'PrevDecl' is being shadowed by a new 259/// declaration at location Loc. Returns true to indicate that this is 260/// an error, and false otherwise. 261bool Sema::DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl) { 262 assert(PrevDecl->isTemplateParameter() && "Not a template parameter"); 263 264 // Microsoft Visual C++ permits template parameters to be shadowed. 265 if (getLangOptions().Microsoft) 266 return false; 267 268 // C++ [temp.local]p4: 269 // A template-parameter shall not be redeclared within its 270 // scope (including nested scopes). 271 Diag(Loc, diag::err_template_param_shadow) 272 << cast<NamedDecl>(PrevDecl)->getDeclName(); 273 Diag(PrevDecl->getLocation(), diag::note_template_param_here); 274 return true; 275} 276 277/// AdjustDeclIfTemplate - If the given decl happens to be a template, reset 278/// the parameter D to reference the templated declaration and return a pointer 279/// to the template declaration. Otherwise, do nothing to D and return null. 280TemplateDecl *Sema::AdjustDeclIfTemplate(DeclPtrTy &D) { 281 if (TemplateDecl *Temp = dyn_cast_or_null<TemplateDecl>(D.getAs<Decl>())) { 282 D = DeclPtrTy::make(Temp->getTemplatedDecl()); 283 return Temp; 284 } 285 return 0; 286} 287 288static TemplateArgumentLoc translateTemplateArgument(Sema &SemaRef, 289 const ParsedTemplateArgument &Arg) { 290 291 switch (Arg.getKind()) { 292 case ParsedTemplateArgument::Type: { 293 DeclaratorInfo *DI; 294 QualType T = SemaRef.GetTypeFromParser(Arg.getAsType(), &DI); 295 if (!DI) 296 DI = SemaRef.Context.getTrivialDeclaratorInfo(T, Arg.getLocation()); 297 return TemplateArgumentLoc(TemplateArgument(T), DI); 298 } 299 300 case ParsedTemplateArgument::NonType: { 301 Expr *E = static_cast<Expr *>(Arg.getAsExpr()); 302 return TemplateArgumentLoc(TemplateArgument(E), E); 303 } 304 305 case ParsedTemplateArgument::Template: { 306 TemplateName Template 307 = TemplateName::getFromVoidPointer(Arg.getAsTemplate().get()); 308 return TemplateArgumentLoc(TemplateArgument(Template), 309 Arg.getScopeSpec().getRange(), 310 Arg.getLocation()); 311 } 312 } 313 314 llvm::llvm_unreachable("Unhandled parsed template argument"); 315 return TemplateArgumentLoc(); 316} 317 318/// \brief Translates template arguments as provided by the parser 319/// into template arguments used by semantic analysis. 320void Sema::translateTemplateArguments(ASTTemplateArgsPtr &TemplateArgsIn, 321 llvm::SmallVectorImpl<TemplateArgumentLoc> &TemplateArgs) { 322 TemplateArgs.reserve(TemplateArgsIn.size()); 323 324 for (unsigned I = 0, Last = TemplateArgsIn.size(); I != Last; ++I) 325 TemplateArgs.push_back(translateTemplateArgument(*this, TemplateArgsIn[I])); 326} 327 328/// ActOnTypeParameter - Called when a C++ template type parameter 329/// (e.g., "typename T") has been parsed. Typename specifies whether 330/// the keyword "typename" was used to declare the type parameter 331/// (otherwise, "class" was used), and KeyLoc is the location of the 332/// "class" or "typename" keyword. ParamName is the name of the 333/// parameter (NULL indicates an unnamed template parameter) and 334/// ParamName is the location of the parameter name (if any). 335/// If the type parameter has a default argument, it will be added 336/// later via ActOnTypeParameterDefault. 337Sema::DeclPtrTy Sema::ActOnTypeParameter(Scope *S, bool Typename, bool Ellipsis, 338 SourceLocation EllipsisLoc, 339 SourceLocation KeyLoc, 340 IdentifierInfo *ParamName, 341 SourceLocation ParamNameLoc, 342 unsigned Depth, unsigned Position) { 343 assert(S->isTemplateParamScope() && 344 "Template type parameter not in template parameter scope!"); 345 bool Invalid = false; 346 347 if (ParamName) { 348 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, LookupTagName); 349 if (PrevDecl && PrevDecl->isTemplateParameter()) 350 Invalid = Invalid || DiagnoseTemplateParameterShadow(ParamNameLoc, 351 PrevDecl); 352 } 353 354 SourceLocation Loc = ParamNameLoc; 355 if (!ParamName) 356 Loc = KeyLoc; 357 358 TemplateTypeParmDecl *Param 359 = TemplateTypeParmDecl::Create(Context, CurContext, Loc, 360 Depth, Position, ParamName, Typename, 361 Ellipsis); 362 if (Invalid) 363 Param->setInvalidDecl(); 364 365 if (ParamName) { 366 // Add the template parameter into the current scope. 367 S->AddDecl(DeclPtrTy::make(Param)); 368 IdResolver.AddDecl(Param); 369 } 370 371 return DeclPtrTy::make(Param); 372} 373 374/// ActOnTypeParameterDefault - Adds a default argument (the type 375/// Default) to the given template type parameter (TypeParam). 376void Sema::ActOnTypeParameterDefault(DeclPtrTy TypeParam, 377 SourceLocation EqualLoc, 378 SourceLocation DefaultLoc, 379 TypeTy *DefaultT) { 380 TemplateTypeParmDecl *Parm 381 = cast<TemplateTypeParmDecl>(TypeParam.getAs<Decl>()); 382 383 DeclaratorInfo *DefaultDInfo; 384 GetTypeFromParser(DefaultT, &DefaultDInfo); 385 386 assert(DefaultDInfo && "expected source information for type"); 387 388 // C++0x [temp.param]p9: 389 // A default template-argument may be specified for any kind of 390 // template-parameter that is not a template parameter pack. 391 if (Parm->isParameterPack()) { 392 Diag(DefaultLoc, diag::err_template_param_pack_default_arg); 393 return; 394 } 395 396 // C++ [temp.param]p14: 397 // A template-parameter shall not be used in its own default argument. 398 // FIXME: Implement this check! Needs a recursive walk over the types. 399 400 // Check the template argument itself. 401 if (CheckTemplateArgument(Parm, DefaultDInfo)) { 402 Parm->setInvalidDecl(); 403 return; 404 } 405 406 Parm->setDefaultArgument(DefaultDInfo, false); 407} 408 409/// \brief Check that the type of a non-type template parameter is 410/// well-formed. 411/// 412/// \returns the (possibly-promoted) parameter type if valid; 413/// otherwise, produces a diagnostic and returns a NULL type. 414QualType 415Sema::CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc) { 416 // C++ [temp.param]p4: 417 // 418 // A non-type template-parameter shall have one of the following 419 // (optionally cv-qualified) types: 420 // 421 // -- integral or enumeration type, 422 if (T->isIntegralType() || T->isEnumeralType() || 423 // -- pointer to object or pointer to function, 424 (T->isPointerType() && 425 (T->getAs<PointerType>()->getPointeeType()->isObjectType() || 426 T->getAs<PointerType>()->getPointeeType()->isFunctionType())) || 427 // -- reference to object or reference to function, 428 T->isReferenceType() || 429 // -- pointer to member. 430 T->isMemberPointerType() || 431 // If T is a dependent type, we can't do the check now, so we 432 // assume that it is well-formed. 433 T->isDependentType()) 434 return T; 435 // C++ [temp.param]p8: 436 // 437 // A non-type template-parameter of type "array of T" or 438 // "function returning T" is adjusted to be of type "pointer to 439 // T" or "pointer to function returning T", respectively. 440 else if (T->isArrayType()) 441 // FIXME: Keep the type prior to promotion? 442 return Context.getArrayDecayedType(T); 443 else if (T->isFunctionType()) 444 // FIXME: Keep the type prior to promotion? 445 return Context.getPointerType(T); 446 447 Diag(Loc, diag::err_template_nontype_parm_bad_type) 448 << T; 449 450 return QualType(); 451} 452 453/// ActOnNonTypeTemplateParameter - Called when a C++ non-type 454/// template parameter (e.g., "int Size" in "template<int Size> 455/// class Array") has been parsed. S is the current scope and D is 456/// the parsed declarator. 457Sema::DeclPtrTy Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D, 458 unsigned Depth, 459 unsigned Position) { 460 DeclaratorInfo *DInfo = 0; 461 QualType T = GetTypeForDeclarator(D, S, &DInfo); 462 463 assert(S->isTemplateParamScope() && 464 "Non-type template parameter not in template parameter scope!"); 465 bool Invalid = false; 466 467 IdentifierInfo *ParamName = D.getIdentifier(); 468 if (ParamName) { 469 NamedDecl *PrevDecl = LookupSingleName(S, ParamName, LookupTagName); 470 if (PrevDecl && PrevDecl->isTemplateParameter()) 471 Invalid = Invalid || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 472 PrevDecl); 473 } 474 475 T = CheckNonTypeTemplateParameterType(T, D.getIdentifierLoc()); 476 if (T.isNull()) { 477 T = Context.IntTy; // Recover with an 'int' type. 478 Invalid = true; 479 } 480 481 NonTypeTemplateParmDecl *Param 482 = NonTypeTemplateParmDecl::Create(Context, CurContext, D.getIdentifierLoc(), 483 Depth, Position, ParamName, T, DInfo); 484 if (Invalid) 485 Param->setInvalidDecl(); 486 487 if (D.getIdentifier()) { 488 // Add the template parameter into the current scope. 489 S->AddDecl(DeclPtrTy::make(Param)); 490 IdResolver.AddDecl(Param); 491 } 492 return DeclPtrTy::make(Param); 493} 494 495/// \brief Adds a default argument to the given non-type template 496/// parameter. 497void Sema::ActOnNonTypeTemplateParameterDefault(DeclPtrTy TemplateParamD, 498 SourceLocation EqualLoc, 499 ExprArg DefaultE) { 500 NonTypeTemplateParmDecl *TemplateParm 501 = cast<NonTypeTemplateParmDecl>(TemplateParamD.getAs<Decl>()); 502 Expr *Default = static_cast<Expr *>(DefaultE.get()); 503 504 // C++ [temp.param]p14: 505 // A template-parameter shall not be used in its own default argument. 506 // FIXME: Implement this check! Needs a recursive walk over the types. 507 508 // Check the well-formedness of the default template argument. 509 TemplateArgument Converted; 510 if (CheckTemplateArgument(TemplateParm, TemplateParm->getType(), Default, 511 Converted)) { 512 TemplateParm->setInvalidDecl(); 513 return; 514 } 515 516 TemplateParm->setDefaultArgument(DefaultE.takeAs<Expr>()); 517} 518 519 520/// ActOnTemplateTemplateParameter - Called when a C++ template template 521/// parameter (e.g. T in template <template <typename> class T> class array) 522/// has been parsed. S is the current scope. 523Sema::DeclPtrTy Sema::ActOnTemplateTemplateParameter(Scope* S, 524 SourceLocation TmpLoc, 525 TemplateParamsTy *Params, 526 IdentifierInfo *Name, 527 SourceLocation NameLoc, 528 unsigned Depth, 529 unsigned Position) { 530 assert(S->isTemplateParamScope() && 531 "Template template parameter not in template parameter scope!"); 532 533 // Construct the parameter object. 534 TemplateTemplateParmDecl *Param = 535 TemplateTemplateParmDecl::Create(Context, CurContext, TmpLoc, Depth, 536 Position, Name, 537 (TemplateParameterList*)Params); 538 539 // Make sure the parameter is valid. 540 // FIXME: Decl object is not currently invalidated anywhere so this doesn't 541 // do anything yet. However, if the template parameter list or (eventual) 542 // default value is ever invalidated, that will propagate here. 543 bool Invalid = false; 544 if (Invalid) { 545 Param->setInvalidDecl(); 546 } 547 548 // If the tt-param has a name, then link the identifier into the scope 549 // and lookup mechanisms. 550 if (Name) { 551 S->AddDecl(DeclPtrTy::make(Param)); 552 IdResolver.AddDecl(Param); 553 } 554 555 return DeclPtrTy::make(Param); 556} 557 558/// \brief Adds a default argument to the given template template 559/// parameter. 560void Sema::ActOnTemplateTemplateParameterDefault(DeclPtrTy TemplateParamD, 561 SourceLocation EqualLoc, 562 const ParsedTemplateArgument &Default) { 563 TemplateTemplateParmDecl *TemplateParm 564 = cast<TemplateTemplateParmDecl>(TemplateParamD.getAs<Decl>()); 565 566 // C++ [temp.param]p14: 567 // A template-parameter shall not be used in its own default argument. 568 // FIXME: Implement this check! Needs a recursive walk over the types. 569 570 // Check only that we have a template template argument. We don't want to 571 // try to check well-formedness now, because our template template parameter 572 // might have dependent types in its template parameters, which we wouldn't 573 // be able to match now. 574 // 575 // If none of the template template parameter's template arguments mention 576 // other template parameters, we could actually perform more checking here. 577 // However, it isn't worth doing. 578 TemplateArgumentLoc DefaultArg = translateTemplateArgument(*this, Default); 579 if (DefaultArg.getArgument().getAsTemplate().isNull()) { 580 Diag(DefaultArg.getLocation(), diag::err_template_arg_not_class_template) 581 << DefaultArg.getSourceRange(); 582 return; 583 } 584 585 TemplateParm->setDefaultArgument(DefaultArg); 586} 587 588/// ActOnTemplateParameterList - Builds a TemplateParameterList that 589/// contains the template parameters in Params/NumParams. 590Sema::TemplateParamsTy * 591Sema::ActOnTemplateParameterList(unsigned Depth, 592 SourceLocation ExportLoc, 593 SourceLocation TemplateLoc, 594 SourceLocation LAngleLoc, 595 DeclPtrTy *Params, unsigned NumParams, 596 SourceLocation RAngleLoc) { 597 if (ExportLoc.isValid()) 598 Diag(ExportLoc, diag::note_template_export_unsupported); 599 600 return TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc, 601 (NamedDecl**)Params, NumParams, 602 RAngleLoc); 603} 604 605Sema::DeclResult 606Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK, 607 SourceLocation KWLoc, const CXXScopeSpec &SS, 608 IdentifierInfo *Name, SourceLocation NameLoc, 609 AttributeList *Attr, 610 TemplateParameterList *TemplateParams, 611 AccessSpecifier AS) { 612 assert(TemplateParams && TemplateParams->size() > 0 && 613 "No template parameters"); 614 assert(TUK != TUK_Reference && "Can only declare or define class templates"); 615 bool Invalid = false; 616 617 // Check that we can declare a template here. 618 if (CheckTemplateDeclScope(S, TemplateParams)) 619 return true; 620 621 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 622 assert(Kind != TagDecl::TK_enum && "can't build template of enumerated type"); 623 624 // There is no such thing as an unnamed class template. 625 if (!Name) { 626 Diag(KWLoc, diag::err_template_unnamed_class); 627 return true; 628 } 629 630 // Find any previous declaration with this name. 631 DeclContext *SemanticContext; 632 LookupResult Previous(*this, Name, NameLoc, LookupOrdinaryName, 633 ForRedeclaration); 634 if (SS.isNotEmpty() && !SS.isInvalid()) { 635 if (RequireCompleteDeclContext(SS)) 636 return true; 637 638 SemanticContext = computeDeclContext(SS, true); 639 if (!SemanticContext) { 640 // FIXME: Produce a reasonable diagnostic here 641 return true; 642 } 643 644 LookupQualifiedName(Previous, SemanticContext); 645 } else { 646 SemanticContext = CurContext; 647 LookupName(Previous, S); 648 } 649 650 assert(!Previous.isAmbiguous() && "Ambiguity in class template redecl?"); 651 NamedDecl *PrevDecl = 0; 652 if (Previous.begin() != Previous.end()) 653 PrevDecl = *Previous.begin(); 654 655 if (PrevDecl && TUK == TUK_Friend) { 656 // C++ [namespace.memdef]p3: 657 // [...] When looking for a prior declaration of a class or a function 658 // declared as a friend, and when the name of the friend class or 659 // function is neither a qualified name nor a template-id, scopes outside 660 // the innermost enclosing namespace scope are not considered. 661 DeclContext *OutermostContext = CurContext; 662 while (!OutermostContext->isFileContext()) 663 OutermostContext = OutermostContext->getLookupParent(); 664 665 if (OutermostContext->Equals(PrevDecl->getDeclContext()) || 666 OutermostContext->Encloses(PrevDecl->getDeclContext())) { 667 SemanticContext = PrevDecl->getDeclContext(); 668 } else { 669 // Declarations in outer scopes don't matter. However, the outermost 670 // context we computed is the semantic context for our new 671 // declaration. 672 PrevDecl = 0; 673 SemanticContext = OutermostContext; 674 } 675 676 if (CurContext->isDependentContext()) { 677 // If this is a dependent context, we don't want to link the friend 678 // class template to the template in scope, because that would perform 679 // checking of the template parameter lists that can't be performed 680 // until the outer context is instantiated. 681 PrevDecl = 0; 682 } 683 } else if (PrevDecl && !isDeclInScope(PrevDecl, SemanticContext, S)) 684 PrevDecl = 0; 685 686 // If there is a previous declaration with the same name, check 687 // whether this is a valid redeclaration. 688 ClassTemplateDecl *PrevClassTemplate 689 = dyn_cast_or_null<ClassTemplateDecl>(PrevDecl); 690 691 // We may have found the injected-class-name of a class template, 692 // class template partial specialization, or class template specialization. 693 // In these cases, grab the template that is being defined or specialized. 694 if (!PrevClassTemplate && PrevDecl && isa<CXXRecordDecl>(PrevDecl) && 695 cast<CXXRecordDecl>(PrevDecl)->isInjectedClassName()) { 696 PrevDecl = cast<CXXRecordDecl>(PrevDecl->getDeclContext()); 697 PrevClassTemplate 698 = cast<CXXRecordDecl>(PrevDecl)->getDescribedClassTemplate(); 699 if (!PrevClassTemplate && isa<ClassTemplateSpecializationDecl>(PrevDecl)) { 700 PrevClassTemplate 701 = cast<ClassTemplateSpecializationDecl>(PrevDecl) 702 ->getSpecializedTemplate(); 703 } 704 } 705 706 if (PrevClassTemplate) { 707 // Ensure that the template parameter lists are compatible. 708 if (!TemplateParameterListsAreEqual(TemplateParams, 709 PrevClassTemplate->getTemplateParameters(), 710 /*Complain=*/true, 711 TPL_TemplateMatch)) 712 return true; 713 714 // C++ [temp.class]p4: 715 // In a redeclaration, partial specialization, explicit 716 // specialization or explicit instantiation of a class template, 717 // the class-key shall agree in kind with the original class 718 // template declaration (7.1.5.3). 719 RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl(); 720 if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) { 721 Diag(KWLoc, diag::err_use_with_wrong_tag) 722 << Name 723 << CodeModificationHint::CreateReplacement(KWLoc, 724 PrevRecordDecl->getKindName()); 725 Diag(PrevRecordDecl->getLocation(), diag::note_previous_use); 726 Kind = PrevRecordDecl->getTagKind(); 727 } 728 729 // Check for redefinition of this class template. 730 if (TUK == TUK_Definition) { 731 if (TagDecl *Def = PrevRecordDecl->getDefinition(Context)) { 732 Diag(NameLoc, diag::err_redefinition) << Name; 733 Diag(Def->getLocation(), diag::note_previous_definition); 734 // FIXME: Would it make sense to try to "forget" the previous 735 // definition, as part of error recovery? 736 return true; 737 } 738 } 739 } else if (PrevDecl && PrevDecl->isTemplateParameter()) { 740 // Maybe we will complain about the shadowed template parameter. 741 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 742 // Just pretend that we didn't see the previous declaration. 743 PrevDecl = 0; 744 } else if (PrevDecl) { 745 // C++ [temp]p5: 746 // A class template shall not have the same name as any other 747 // template, class, function, object, enumeration, enumerator, 748 // namespace, or type in the same scope (3.3), except as specified 749 // in (14.5.4). 750 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 751 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 752 return true; 753 } 754 755 // Check the template parameter list of this declaration, possibly 756 // merging in the template parameter list from the previous class 757 // template declaration. 758 if (CheckTemplateParameterList(TemplateParams, 759 PrevClassTemplate? PrevClassTemplate->getTemplateParameters() : 0)) 760 Invalid = true; 761 762 // FIXME: If we had a scope specifier, we better have a previous template 763 // declaration! 764 765 CXXRecordDecl *NewClass = 766 CXXRecordDecl::Create(Context, Kind, SemanticContext, NameLoc, Name, KWLoc, 767 PrevClassTemplate? 768 PrevClassTemplate->getTemplatedDecl() : 0, 769 /*DelayTypeCreation=*/true); 770 771 ClassTemplateDecl *NewTemplate 772 = ClassTemplateDecl::Create(Context, SemanticContext, NameLoc, 773 DeclarationName(Name), TemplateParams, 774 NewClass, PrevClassTemplate); 775 NewClass->setDescribedClassTemplate(NewTemplate); 776 777 // Build the type for the class template declaration now. 778 QualType T = 779 Context.getTypeDeclType(NewClass, 780 PrevClassTemplate? 781 PrevClassTemplate->getTemplatedDecl() : 0); 782 assert(T->isDependentType() && "Class template type is not dependent?"); 783 (void)T; 784 785 // If we are providing an explicit specialization of a member that is a 786 // class template, make a note of that. 787 if (PrevClassTemplate && 788 PrevClassTemplate->getInstantiatedFromMemberTemplate()) 789 PrevClassTemplate->setMemberSpecialization(); 790 791 // Set the access specifier. 792 if (!Invalid && TUK != TUK_Friend) 793 SetMemberAccessSpecifier(NewTemplate, PrevClassTemplate, AS); 794 795 // Set the lexical context of these templates 796 NewClass->setLexicalDeclContext(CurContext); 797 NewTemplate->setLexicalDeclContext(CurContext); 798 799 if (TUK == TUK_Definition) 800 NewClass->startDefinition(); 801 802 if (Attr) 803 ProcessDeclAttributeList(S, NewClass, Attr); 804 805 if (TUK != TUK_Friend) 806 PushOnScopeChains(NewTemplate, S); 807 else { 808 if (PrevClassTemplate && PrevClassTemplate->getAccess() != AS_none) { 809 NewTemplate->setAccess(PrevClassTemplate->getAccess()); 810 NewClass->setAccess(PrevClassTemplate->getAccess()); 811 } 812 813 NewTemplate->setObjectOfFriendDecl(/* PreviouslyDeclared = */ 814 PrevClassTemplate != NULL); 815 816 // Friend templates are visible in fairly strange ways. 817 if (!CurContext->isDependentContext()) { 818 DeclContext *DC = SemanticContext->getLookupContext(); 819 DC->makeDeclVisibleInContext(NewTemplate, /* Recoverable = */ false); 820 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 821 PushOnScopeChains(NewTemplate, EnclosingScope, 822 /* AddToContext = */ false); 823 } 824 825 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 826 NewClass->getLocation(), 827 NewTemplate, 828 /*FIXME:*/NewClass->getLocation()); 829 Friend->setAccess(AS_public); 830 CurContext->addDecl(Friend); 831 } 832 833 if (Invalid) { 834 NewTemplate->setInvalidDecl(); 835 NewClass->setInvalidDecl(); 836 } 837 return DeclPtrTy::make(NewTemplate); 838} 839 840/// \brief Checks the validity of a template parameter list, possibly 841/// considering the template parameter list from a previous 842/// declaration. 843/// 844/// If an "old" template parameter list is provided, it must be 845/// equivalent (per TemplateParameterListsAreEqual) to the "new" 846/// template parameter list. 847/// 848/// \param NewParams Template parameter list for a new template 849/// declaration. This template parameter list will be updated with any 850/// default arguments that are carried through from the previous 851/// template parameter list. 852/// 853/// \param OldParams If provided, template parameter list from a 854/// previous declaration of the same template. Default template 855/// arguments will be merged from the old template parameter list to 856/// the new template parameter list. 857/// 858/// \returns true if an error occurred, false otherwise. 859bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams, 860 TemplateParameterList *OldParams) { 861 bool Invalid = false; 862 863 // C++ [temp.param]p10: 864 // The set of default template-arguments available for use with a 865 // template declaration or definition is obtained by merging the 866 // default arguments from the definition (if in scope) and all 867 // declarations in scope in the same way default function 868 // arguments are (8.3.6). 869 bool SawDefaultArgument = false; 870 SourceLocation PreviousDefaultArgLoc; 871 872 bool SawParameterPack = false; 873 SourceLocation ParameterPackLoc; 874 875 // Dummy initialization to avoid warnings. 876 TemplateParameterList::iterator OldParam = NewParams->end(); 877 if (OldParams) 878 OldParam = OldParams->begin(); 879 880 for (TemplateParameterList::iterator NewParam = NewParams->begin(), 881 NewParamEnd = NewParams->end(); 882 NewParam != NewParamEnd; ++NewParam) { 883 // Variables used to diagnose redundant default arguments 884 bool RedundantDefaultArg = false; 885 SourceLocation OldDefaultLoc; 886 SourceLocation NewDefaultLoc; 887 888 // Variables used to diagnose missing default arguments 889 bool MissingDefaultArg = false; 890 891 // C++0x [temp.param]p11: 892 // If a template parameter of a class template is a template parameter pack, 893 // it must be the last template parameter. 894 if (SawParameterPack) { 895 Diag(ParameterPackLoc, 896 diag::err_template_param_pack_must_be_last_template_parameter); 897 Invalid = true; 898 } 899 900 // Merge default arguments for template type parameters. 901 if (TemplateTypeParmDecl *NewTypeParm 902 = dyn_cast<TemplateTypeParmDecl>(*NewParam)) { 903 TemplateTypeParmDecl *OldTypeParm 904 = OldParams? cast<TemplateTypeParmDecl>(*OldParam) : 0; 905 906 if (NewTypeParm->isParameterPack()) { 907 assert(!NewTypeParm->hasDefaultArgument() && 908 "Parameter packs can't have a default argument!"); 909 SawParameterPack = true; 910 ParameterPackLoc = NewTypeParm->getLocation(); 911 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument() && 912 NewTypeParm->hasDefaultArgument()) { 913 OldDefaultLoc = OldTypeParm->getDefaultArgumentLoc(); 914 NewDefaultLoc = NewTypeParm->getDefaultArgumentLoc(); 915 SawDefaultArgument = true; 916 RedundantDefaultArg = true; 917 PreviousDefaultArgLoc = NewDefaultLoc; 918 } else if (OldTypeParm && OldTypeParm->hasDefaultArgument()) { 919 // Merge the default argument from the old declaration to the 920 // new declaration. 921 SawDefaultArgument = true; 922 NewTypeParm->setDefaultArgument(OldTypeParm->getDefaultArgumentInfo(), 923 true); 924 PreviousDefaultArgLoc = OldTypeParm->getDefaultArgumentLoc(); 925 } else if (NewTypeParm->hasDefaultArgument()) { 926 SawDefaultArgument = true; 927 PreviousDefaultArgLoc = NewTypeParm->getDefaultArgumentLoc(); 928 } else if (SawDefaultArgument) 929 MissingDefaultArg = true; 930 } else if (NonTypeTemplateParmDecl *NewNonTypeParm 931 = dyn_cast<NonTypeTemplateParmDecl>(*NewParam)) { 932 // Merge default arguments for non-type template parameters 933 NonTypeTemplateParmDecl *OldNonTypeParm 934 = OldParams? cast<NonTypeTemplateParmDecl>(*OldParam) : 0; 935 if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument() && 936 NewNonTypeParm->hasDefaultArgument()) { 937 OldDefaultLoc = OldNonTypeParm->getDefaultArgumentLoc(); 938 NewDefaultLoc = NewNonTypeParm->getDefaultArgumentLoc(); 939 SawDefaultArgument = true; 940 RedundantDefaultArg = true; 941 PreviousDefaultArgLoc = NewDefaultLoc; 942 } else if (OldNonTypeParm && OldNonTypeParm->hasDefaultArgument()) { 943 // Merge the default argument from the old declaration to the 944 // new declaration. 945 SawDefaultArgument = true; 946 // FIXME: We need to create a new kind of "default argument" 947 // expression that points to a previous template template 948 // parameter. 949 NewNonTypeParm->setDefaultArgument( 950 OldNonTypeParm->getDefaultArgument()); 951 PreviousDefaultArgLoc = OldNonTypeParm->getDefaultArgumentLoc(); 952 } else if (NewNonTypeParm->hasDefaultArgument()) { 953 SawDefaultArgument = true; 954 PreviousDefaultArgLoc = NewNonTypeParm->getDefaultArgumentLoc(); 955 } else if (SawDefaultArgument) 956 MissingDefaultArg = true; 957 } else { 958 // Merge default arguments for template template parameters 959 TemplateTemplateParmDecl *NewTemplateParm 960 = cast<TemplateTemplateParmDecl>(*NewParam); 961 TemplateTemplateParmDecl *OldTemplateParm 962 = OldParams? cast<TemplateTemplateParmDecl>(*OldParam) : 0; 963 if (OldTemplateParm && OldTemplateParm->hasDefaultArgument() && 964 NewTemplateParm->hasDefaultArgument()) { 965 OldDefaultLoc = OldTemplateParm->getDefaultArgument().getLocation(); 966 NewDefaultLoc = NewTemplateParm->getDefaultArgument().getLocation(); 967 SawDefaultArgument = true; 968 RedundantDefaultArg = true; 969 PreviousDefaultArgLoc = NewDefaultLoc; 970 } else if (OldTemplateParm && OldTemplateParm->hasDefaultArgument()) { 971 // Merge the default argument from the old declaration to the 972 // new declaration. 973 SawDefaultArgument = true; 974 // FIXME: We need to create a new kind of "default argument" expression 975 // that points to a previous template template parameter. 976 NewTemplateParm->setDefaultArgument( 977 OldTemplateParm->getDefaultArgument()); 978 PreviousDefaultArgLoc 979 = OldTemplateParm->getDefaultArgument().getLocation(); 980 } else if (NewTemplateParm->hasDefaultArgument()) { 981 SawDefaultArgument = true; 982 PreviousDefaultArgLoc 983 = NewTemplateParm->getDefaultArgument().getLocation(); 984 } else if (SawDefaultArgument) 985 MissingDefaultArg = true; 986 } 987 988 if (RedundantDefaultArg) { 989 // C++ [temp.param]p12: 990 // A template-parameter shall not be given default arguments 991 // by two different declarations in the same scope. 992 Diag(NewDefaultLoc, diag::err_template_param_default_arg_redefinition); 993 Diag(OldDefaultLoc, diag::note_template_param_prev_default_arg); 994 Invalid = true; 995 } else if (MissingDefaultArg) { 996 // C++ [temp.param]p11: 997 // If a template-parameter has a default template-argument, 998 // all subsequent template-parameters shall have a default 999 // template-argument supplied. 1000 Diag((*NewParam)->getLocation(), 1001 diag::err_template_param_default_arg_missing); 1002 Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg); 1003 Invalid = true; 1004 } 1005 1006 // If we have an old template parameter list that we're merging 1007 // in, move on to the next parameter. 1008 if (OldParams) 1009 ++OldParam; 1010 } 1011 1012 return Invalid; 1013} 1014 1015/// \brief Match the given template parameter lists to the given scope 1016/// specifier, returning the template parameter list that applies to the 1017/// name. 1018/// 1019/// \param DeclStartLoc the start of the declaration that has a scope 1020/// specifier or a template parameter list. 1021/// 1022/// \param SS the scope specifier that will be matched to the given template 1023/// parameter lists. This scope specifier precedes a qualified name that is 1024/// being declared. 1025/// 1026/// \param ParamLists the template parameter lists, from the outermost to the 1027/// innermost template parameter lists. 1028/// 1029/// \param NumParamLists the number of template parameter lists in ParamLists. 1030/// 1031/// \param IsExplicitSpecialization will be set true if the entity being 1032/// declared is an explicit specialization, false otherwise. 1033/// 1034/// \returns the template parameter list, if any, that corresponds to the 1035/// name that is preceded by the scope specifier @p SS. This template 1036/// parameter list may be have template parameters (if we're declaring a 1037/// template) or may have no template parameters (if we're declaring a 1038/// template specialization), or may be NULL (if we were's declaring isn't 1039/// itself a template). 1040TemplateParameterList * 1041Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc, 1042 const CXXScopeSpec &SS, 1043 TemplateParameterList **ParamLists, 1044 unsigned NumParamLists, 1045 bool &IsExplicitSpecialization) { 1046 IsExplicitSpecialization = false; 1047 1048 // Find the template-ids that occur within the nested-name-specifier. These 1049 // template-ids will match up with the template parameter lists. 1050 llvm::SmallVector<const TemplateSpecializationType *, 4> 1051 TemplateIdsInSpecifier; 1052 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 1053 NNS; NNS = NNS->getPrefix()) { 1054 if (const TemplateSpecializationType *SpecType 1055 = dyn_cast_or_null<TemplateSpecializationType>(NNS->getAsType())) { 1056 TemplateDecl *Template = SpecType->getTemplateName().getAsTemplateDecl(); 1057 if (!Template) 1058 continue; // FIXME: should this be an error? probably... 1059 1060 if (const RecordType *Record = SpecType->getAs<RecordType>()) { 1061 ClassTemplateSpecializationDecl *SpecDecl 1062 = cast<ClassTemplateSpecializationDecl>(Record->getDecl()); 1063 // If the nested name specifier refers to an explicit specialization, 1064 // we don't need a template<> header. 1065 // FIXME: revisit this approach once we cope with specializations 1066 // properly. 1067 if (SpecDecl->getSpecializationKind() == TSK_ExplicitSpecialization) 1068 continue; 1069 } 1070 1071 TemplateIdsInSpecifier.push_back(SpecType); 1072 } 1073 } 1074 1075 // Reverse the list of template-ids in the scope specifier, so that we can 1076 // more easily match up the template-ids and the template parameter lists. 1077 std::reverse(TemplateIdsInSpecifier.begin(), TemplateIdsInSpecifier.end()); 1078 1079 SourceLocation FirstTemplateLoc = DeclStartLoc; 1080 if (NumParamLists) 1081 FirstTemplateLoc = ParamLists[0]->getTemplateLoc(); 1082 1083 // Match the template-ids found in the specifier to the template parameter 1084 // lists. 1085 unsigned Idx = 0; 1086 for (unsigned NumTemplateIds = TemplateIdsInSpecifier.size(); 1087 Idx != NumTemplateIds; ++Idx) { 1088 QualType TemplateId = QualType(TemplateIdsInSpecifier[Idx], 0); 1089 bool DependentTemplateId = TemplateId->isDependentType(); 1090 if (Idx >= NumParamLists) { 1091 // We have a template-id without a corresponding template parameter 1092 // list. 1093 if (DependentTemplateId) { 1094 // FIXME: the location information here isn't great. 1095 Diag(SS.getRange().getBegin(), 1096 diag::err_template_spec_needs_template_parameters) 1097 << TemplateId 1098 << SS.getRange(); 1099 } else { 1100 Diag(SS.getRange().getBegin(), diag::err_template_spec_needs_header) 1101 << SS.getRange() 1102 << CodeModificationHint::CreateInsertion(FirstTemplateLoc, 1103 "template<> "); 1104 IsExplicitSpecialization = true; 1105 } 1106 return 0; 1107 } 1108 1109 // Check the template parameter list against its corresponding template-id. 1110 if (DependentTemplateId) { 1111 TemplateDecl *Template 1112 = TemplateIdsInSpecifier[Idx]->getTemplateName().getAsTemplateDecl(); 1113 1114 if (ClassTemplateDecl *ClassTemplate 1115 = dyn_cast<ClassTemplateDecl>(Template)) { 1116 TemplateParameterList *ExpectedTemplateParams = 0; 1117 // Is this template-id naming the primary template? 1118 if (Context.hasSameType(TemplateId, 1119 ClassTemplate->getInjectedClassNameType(Context))) 1120 ExpectedTemplateParams = ClassTemplate->getTemplateParameters(); 1121 // ... or a partial specialization? 1122 else if (ClassTemplatePartialSpecializationDecl *PartialSpec 1123 = ClassTemplate->findPartialSpecialization(TemplateId)) 1124 ExpectedTemplateParams = PartialSpec->getTemplateParameters(); 1125 1126 if (ExpectedTemplateParams) 1127 TemplateParameterListsAreEqual(ParamLists[Idx], 1128 ExpectedTemplateParams, 1129 true, TPL_TemplateMatch); 1130 } 1131 } else if (ParamLists[Idx]->size() > 0) 1132 Diag(ParamLists[Idx]->getTemplateLoc(), 1133 diag::err_template_param_list_matches_nontemplate) 1134 << TemplateId 1135 << ParamLists[Idx]->getSourceRange(); 1136 else 1137 IsExplicitSpecialization = true; 1138 } 1139 1140 // If there were at least as many template-ids as there were template 1141 // parameter lists, then there are no template parameter lists remaining for 1142 // the declaration itself. 1143 if (Idx >= NumParamLists) 1144 return 0; 1145 1146 // If there were too many template parameter lists, complain about that now. 1147 if (Idx != NumParamLists - 1) { 1148 while (Idx < NumParamLists - 1) { 1149 Diag(ParamLists[Idx]->getTemplateLoc(), 1150 diag::err_template_spec_extra_headers) 1151 << SourceRange(ParamLists[Idx]->getTemplateLoc(), 1152 ParamLists[Idx]->getRAngleLoc()); 1153 ++Idx; 1154 } 1155 } 1156 1157 // Return the last template parameter list, which corresponds to the 1158 // entity being declared. 1159 return ParamLists[NumParamLists - 1]; 1160} 1161 1162QualType Sema::CheckTemplateIdType(TemplateName Name, 1163 SourceLocation TemplateLoc, 1164 SourceLocation LAngleLoc, 1165 const TemplateArgumentLoc *TemplateArgs, 1166 unsigned NumTemplateArgs, 1167 SourceLocation RAngleLoc) { 1168 TemplateDecl *Template = Name.getAsTemplateDecl(); 1169 if (!Template) { 1170 // The template name does not resolve to a template, so we just 1171 // build a dependent template-id type. 1172 return Context.getTemplateSpecializationType(Name, TemplateArgs, 1173 NumTemplateArgs); 1174 } 1175 1176 // Check that the template argument list is well-formed for this 1177 // template. 1178 TemplateArgumentListBuilder Converted(Template->getTemplateParameters(), 1179 NumTemplateArgs); 1180 if (CheckTemplateArgumentList(Template, TemplateLoc, LAngleLoc, 1181 TemplateArgs, NumTemplateArgs, RAngleLoc, 1182 false, Converted)) 1183 return QualType(); 1184 1185 assert((Converted.structuredSize() == 1186 Template->getTemplateParameters()->size()) && 1187 "Converted template argument list is too short!"); 1188 1189 QualType CanonType; 1190 1191 if (Name.isDependent() || 1192 TemplateSpecializationType::anyDependentTemplateArguments( 1193 TemplateArgs, 1194 NumTemplateArgs)) { 1195 // This class template specialization is a dependent 1196 // type. Therefore, its canonical type is another class template 1197 // specialization type that contains all of the converted 1198 // arguments in canonical form. This ensures that, e.g., A<T> and 1199 // A<T, T> have identical types when A is declared as: 1200 // 1201 // template<typename T, typename U = T> struct A; 1202 TemplateName CanonName = Context.getCanonicalTemplateName(Name); 1203 CanonType = Context.getTemplateSpecializationType(CanonName, 1204 Converted.getFlatArguments(), 1205 Converted.flatSize()); 1206 1207 // FIXME: CanonType is not actually the canonical type, and unfortunately 1208 // it is a TemplateSpecializationType that we will never use again. 1209 // In the future, we need to teach getTemplateSpecializationType to only 1210 // build the canonical type and return that to us. 1211 CanonType = Context.getCanonicalType(CanonType); 1212 } else if (ClassTemplateDecl *ClassTemplate 1213 = dyn_cast<ClassTemplateDecl>(Template)) { 1214 // Find the class template specialization declaration that 1215 // corresponds to these arguments. 1216 llvm::FoldingSetNodeID ID; 1217 ClassTemplateSpecializationDecl::Profile(ID, 1218 Converted.getFlatArguments(), 1219 Converted.flatSize(), 1220 Context); 1221 void *InsertPos = 0; 1222 ClassTemplateSpecializationDecl *Decl 1223 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 1224 if (!Decl) { 1225 // This is the first time we have referenced this class template 1226 // specialization. Create the canonical declaration and add it to 1227 // the set of specializations. 1228 Decl = ClassTemplateSpecializationDecl::Create(Context, 1229 ClassTemplate->getDeclContext(), 1230 ClassTemplate->getLocation(), 1231 ClassTemplate, 1232 Converted, 0); 1233 ClassTemplate->getSpecializations().InsertNode(Decl, InsertPos); 1234 Decl->setLexicalDeclContext(CurContext); 1235 } 1236 1237 CanonType = Context.getTypeDeclType(Decl); 1238 } 1239 1240 // Build the fully-sugared type for this class template 1241 // specialization, which refers back to the class template 1242 // specialization we created or found. 1243 return Context.getTemplateSpecializationType(Name, TemplateArgs, 1244 NumTemplateArgs, CanonType); 1245} 1246 1247Action::TypeResult 1248Sema::ActOnTemplateIdType(TemplateTy TemplateD, SourceLocation TemplateLoc, 1249 SourceLocation LAngleLoc, 1250 ASTTemplateArgsPtr TemplateArgsIn, 1251 SourceLocation RAngleLoc) { 1252 TemplateName Template = TemplateD.getAsVal<TemplateName>(); 1253 1254 // Translate the parser's template argument list in our AST format. 1255 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 1256 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 1257 1258 QualType Result = CheckTemplateIdType(Template, TemplateLoc, LAngleLoc, 1259 TemplateArgs.data(), 1260 TemplateArgs.size(), 1261 RAngleLoc); 1262 TemplateArgsIn.release(); 1263 1264 if (Result.isNull()) 1265 return true; 1266 1267 DeclaratorInfo *DI = Context.CreateDeclaratorInfo(Result); 1268 TemplateSpecializationTypeLoc TL 1269 = cast<TemplateSpecializationTypeLoc>(DI->getTypeLoc()); 1270 TL.setTemplateNameLoc(TemplateLoc); 1271 TL.setLAngleLoc(LAngleLoc); 1272 TL.setRAngleLoc(RAngleLoc); 1273 for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) 1274 TL.setArgLocInfo(i, TemplateArgs[i].getLocInfo()); 1275 1276 return CreateLocInfoType(Result, DI).getAsOpaquePtr(); 1277} 1278 1279Sema::TypeResult Sema::ActOnTagTemplateIdType(TypeResult TypeResult, 1280 TagUseKind TUK, 1281 DeclSpec::TST TagSpec, 1282 SourceLocation TagLoc) { 1283 if (TypeResult.isInvalid()) 1284 return Sema::TypeResult(); 1285 1286 // FIXME: preserve source info, ideally without copying the DI. 1287 DeclaratorInfo *DI; 1288 QualType Type = GetTypeFromParser(TypeResult.get(), &DI); 1289 1290 // Verify the tag specifier. 1291 TagDecl::TagKind TagKind = TagDecl::getTagKindForTypeSpec(TagSpec); 1292 1293 if (const RecordType *RT = Type->getAs<RecordType>()) { 1294 RecordDecl *D = RT->getDecl(); 1295 1296 IdentifierInfo *Id = D->getIdentifier(); 1297 assert(Id && "templated class must have an identifier"); 1298 1299 if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) { 1300 Diag(TagLoc, diag::err_use_with_wrong_tag) 1301 << Type 1302 << CodeModificationHint::CreateReplacement(SourceRange(TagLoc), 1303 D->getKindName()); 1304 Diag(D->getLocation(), diag::note_previous_use); 1305 } 1306 } 1307 1308 QualType ElabType = Context.getElaboratedType(Type, TagKind); 1309 1310 return ElabType.getAsOpaquePtr(); 1311} 1312 1313Sema::OwningExprResult Sema::BuildTemplateIdExpr(NestedNameSpecifier *Qualifier, 1314 SourceRange QualifierRange, 1315 TemplateName Template, 1316 SourceLocation TemplateNameLoc, 1317 SourceLocation LAngleLoc, 1318 const TemplateArgumentLoc *TemplateArgs, 1319 unsigned NumTemplateArgs, 1320 SourceLocation RAngleLoc) { 1321 // FIXME: Can we do any checking at this point? I guess we could check the 1322 // template arguments that we have against the template name, if the template 1323 // name refers to a single template. That's not a terribly common case, 1324 // though. 1325 1326 // Cope with an implicit member access in a C++ non-static member function. 1327 NamedDecl *D = Template.getAsTemplateDecl(); 1328 if (!D) 1329 D = Template.getAsOverloadedFunctionDecl(); 1330 1331 CXXScopeSpec SS; 1332 SS.setRange(QualifierRange); 1333 SS.setScopeRep(Qualifier); 1334 QualType ThisType, MemberType; 1335 if (D && isImplicitMemberReference(&SS, D, TemplateNameLoc, 1336 ThisType, MemberType)) { 1337 Expr *This = new (Context) CXXThisExpr(SourceLocation(), ThisType); 1338 return Owned(MemberExpr::Create(Context, This, true, 1339 Qualifier, QualifierRange, 1340 D, TemplateNameLoc, true, 1341 LAngleLoc, TemplateArgs, 1342 NumTemplateArgs, RAngleLoc, 1343 Context.OverloadTy)); 1344 } 1345 1346 return Owned(TemplateIdRefExpr::Create(Context, Context.OverloadTy, 1347 Qualifier, QualifierRange, 1348 Template, TemplateNameLoc, LAngleLoc, 1349 TemplateArgs, 1350 NumTemplateArgs, RAngleLoc)); 1351} 1352 1353Sema::OwningExprResult Sema::ActOnTemplateIdExpr(const CXXScopeSpec &SS, 1354 TemplateTy TemplateD, 1355 SourceLocation TemplateNameLoc, 1356 SourceLocation LAngleLoc, 1357 ASTTemplateArgsPtr TemplateArgsIn, 1358 SourceLocation RAngleLoc) { 1359 TemplateName Template = TemplateD.getAsVal<TemplateName>(); 1360 1361 // Translate the parser's template argument list in our AST format. 1362 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 1363 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 1364 TemplateArgsIn.release(); 1365 1366 return BuildTemplateIdExpr((NestedNameSpecifier *)SS.getScopeRep(), 1367 SS.getRange(), 1368 Template, TemplateNameLoc, LAngleLoc, 1369 TemplateArgs.data(), TemplateArgs.size(), 1370 RAngleLoc); 1371} 1372 1373/// \brief Form a dependent template name. 1374/// 1375/// This action forms a dependent template name given the template 1376/// name and its (presumably dependent) scope specifier. For 1377/// example, given "MetaFun::template apply", the scope specifier \p 1378/// SS will be "MetaFun::", \p TemplateKWLoc contains the location 1379/// of the "template" keyword, and "apply" is the \p Name. 1380Sema::TemplateTy 1381Sema::ActOnDependentTemplateName(SourceLocation TemplateKWLoc, 1382 const CXXScopeSpec &SS, 1383 UnqualifiedId &Name, 1384 TypeTy *ObjectType) { 1385 if ((ObjectType && 1386 computeDeclContext(QualType::getFromOpaquePtr(ObjectType))) || 1387 (SS.isSet() && computeDeclContext(SS, false))) { 1388 // C++0x [temp.names]p5: 1389 // If a name prefixed by the keyword template is not the name of 1390 // a template, the program is ill-formed. [Note: the keyword 1391 // template may not be applied to non-template members of class 1392 // templates. -end note ] [ Note: as is the case with the 1393 // typename prefix, the template prefix is allowed in cases 1394 // where it is not strictly necessary; i.e., when the 1395 // nested-name-specifier or the expression on the left of the -> 1396 // or . is not dependent on a template-parameter, or the use 1397 // does not appear in the scope of a template. -end note] 1398 // 1399 // Note: C++03 was more strict here, because it banned the use of 1400 // the "template" keyword prior to a template-name that was not a 1401 // dependent name. C++ DR468 relaxed this requirement (the 1402 // "template" keyword is now permitted). We follow the C++0x 1403 // rules, even in C++03 mode, retroactively applying the DR. 1404 TemplateTy Template; 1405 TemplateNameKind TNK = isTemplateName(0, SS, Name, ObjectType, 1406 false, Template); 1407 if (TNK == TNK_Non_template) { 1408 Diag(Name.getSourceRange().getBegin(), 1409 diag::err_template_kw_refers_to_non_template) 1410 << GetNameFromUnqualifiedId(Name) 1411 << Name.getSourceRange(); 1412 return TemplateTy(); 1413 } 1414 1415 return Template; 1416 } 1417 1418 NestedNameSpecifier *Qualifier 1419 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 1420 1421 switch (Name.getKind()) { 1422 case UnqualifiedId::IK_Identifier: 1423 return TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1424 Name.Identifier)); 1425 1426 case UnqualifiedId::IK_OperatorFunctionId: 1427 return TemplateTy::make(Context.getDependentTemplateName(Qualifier, 1428 Name.OperatorFunctionId.Operator)); 1429 1430 default: 1431 break; 1432 } 1433 1434 Diag(Name.getSourceRange().getBegin(), 1435 diag::err_template_kw_refers_to_non_template) 1436 << GetNameFromUnqualifiedId(Name) 1437 << Name.getSourceRange(); 1438 return TemplateTy(); 1439} 1440 1441bool Sema::CheckTemplateTypeArgument(TemplateTypeParmDecl *Param, 1442 const TemplateArgumentLoc &AL, 1443 TemplateArgumentListBuilder &Converted) { 1444 const TemplateArgument &Arg = AL.getArgument(); 1445 1446 // Check template type parameter. 1447 if (Arg.getKind() != TemplateArgument::Type) { 1448 // C++ [temp.arg.type]p1: 1449 // A template-argument for a template-parameter which is a 1450 // type shall be a type-id. 1451 1452 // We have a template type parameter but the template argument 1453 // is not a type. 1454 SourceRange SR = AL.getSourceRange(); 1455 Diag(SR.getBegin(), diag::err_template_arg_must_be_type) << SR; 1456 Diag(Param->getLocation(), diag::note_template_param_here); 1457 1458 return true; 1459 } 1460 1461 if (CheckTemplateArgument(Param, AL.getSourceDeclaratorInfo())) 1462 return true; 1463 1464 // Add the converted template type argument. 1465 Converted.Append( 1466 TemplateArgument(Context.getCanonicalType(Arg.getAsType()))); 1467 return false; 1468} 1469 1470/// \brief Substitute template arguments into the default template argument for 1471/// the given template type parameter. 1472/// 1473/// \param SemaRef the semantic analysis object for which we are performing 1474/// the substitution. 1475/// 1476/// \param Template the template that we are synthesizing template arguments 1477/// for. 1478/// 1479/// \param TemplateLoc the location of the template name that started the 1480/// template-id we are checking. 1481/// 1482/// \param RAngleLoc the location of the right angle bracket ('>') that 1483/// terminates the template-id. 1484/// 1485/// \param Param the template template parameter whose default we are 1486/// substituting into. 1487/// 1488/// \param Converted the list of template arguments provided for template 1489/// parameters that precede \p Param in the template parameter list. 1490/// 1491/// \returns the substituted template argument, or NULL if an error occurred. 1492static DeclaratorInfo * 1493SubstDefaultTemplateArgument(Sema &SemaRef, 1494 TemplateDecl *Template, 1495 SourceLocation TemplateLoc, 1496 SourceLocation RAngleLoc, 1497 TemplateTypeParmDecl *Param, 1498 TemplateArgumentListBuilder &Converted) { 1499 DeclaratorInfo *ArgType = Param->getDefaultArgumentInfo(); 1500 1501 // If the argument type is dependent, instantiate it now based 1502 // on the previously-computed template arguments. 1503 if (ArgType->getType()->isDependentType()) { 1504 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1505 /*TakeArgs=*/false); 1506 1507 MultiLevelTemplateArgumentList AllTemplateArgs 1508 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1509 1510 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1511 Template, Converted.getFlatArguments(), 1512 Converted.flatSize(), 1513 SourceRange(TemplateLoc, RAngleLoc)); 1514 1515 ArgType = SemaRef.SubstType(ArgType, AllTemplateArgs, 1516 Param->getDefaultArgumentLoc(), 1517 Param->getDeclName()); 1518 } 1519 1520 return ArgType; 1521} 1522 1523/// \brief Substitute template arguments into the default template argument for 1524/// the given non-type template parameter. 1525/// 1526/// \param SemaRef the semantic analysis object for which we are performing 1527/// the substitution. 1528/// 1529/// \param Template the template that we are synthesizing template arguments 1530/// for. 1531/// 1532/// \param TemplateLoc the location of the template name that started the 1533/// template-id we are checking. 1534/// 1535/// \param RAngleLoc the location of the right angle bracket ('>') that 1536/// terminates the template-id. 1537/// 1538/// \param Param the non-type template parameter whose default we are 1539/// substituting into. 1540/// 1541/// \param Converted the list of template arguments provided for template 1542/// parameters that precede \p Param in the template parameter list. 1543/// 1544/// \returns the substituted template argument, or NULL if an error occurred. 1545static Sema::OwningExprResult 1546SubstDefaultTemplateArgument(Sema &SemaRef, 1547 TemplateDecl *Template, 1548 SourceLocation TemplateLoc, 1549 SourceLocation RAngleLoc, 1550 NonTypeTemplateParmDecl *Param, 1551 TemplateArgumentListBuilder &Converted) { 1552 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1553 /*TakeArgs=*/false); 1554 1555 MultiLevelTemplateArgumentList AllTemplateArgs 1556 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1557 1558 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1559 Template, Converted.getFlatArguments(), 1560 Converted.flatSize(), 1561 SourceRange(TemplateLoc, RAngleLoc)); 1562 1563 return SemaRef.SubstExpr(Param->getDefaultArgument(), AllTemplateArgs); 1564} 1565 1566/// \brief Substitute template arguments into the default template argument for 1567/// the given template template parameter. 1568/// 1569/// \param SemaRef the semantic analysis object for which we are performing 1570/// the substitution. 1571/// 1572/// \param Template the template that we are synthesizing template arguments 1573/// for. 1574/// 1575/// \param TemplateLoc the location of the template name that started the 1576/// template-id we are checking. 1577/// 1578/// \param RAngleLoc the location of the right angle bracket ('>') that 1579/// terminates the template-id. 1580/// 1581/// \param Param the template template parameter whose default we are 1582/// substituting into. 1583/// 1584/// \param Converted the list of template arguments provided for template 1585/// parameters that precede \p Param in the template parameter list. 1586/// 1587/// \returns the substituted template argument, or NULL if an error occurred. 1588static TemplateName 1589SubstDefaultTemplateArgument(Sema &SemaRef, 1590 TemplateDecl *Template, 1591 SourceLocation TemplateLoc, 1592 SourceLocation RAngleLoc, 1593 TemplateTemplateParmDecl *Param, 1594 TemplateArgumentListBuilder &Converted) { 1595 TemplateArgumentList TemplateArgs(SemaRef.Context, Converted, 1596 /*TakeArgs=*/false); 1597 1598 MultiLevelTemplateArgumentList AllTemplateArgs 1599 = SemaRef.getTemplateInstantiationArgs(Template, &TemplateArgs); 1600 1601 Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, 1602 Template, Converted.getFlatArguments(), 1603 Converted.flatSize(), 1604 SourceRange(TemplateLoc, RAngleLoc)); 1605 1606 return SemaRef.SubstTemplateName( 1607 Param->getDefaultArgument().getArgument().getAsTemplate(), 1608 Param->getDefaultArgument().getTemplateNameLoc(), 1609 AllTemplateArgs); 1610} 1611 1612/// \brief Check that the given template argument corresponds to the given 1613/// template parameter. 1614bool Sema::CheckTemplateArgument(NamedDecl *Param, 1615 const TemplateArgumentLoc &Arg, 1616 TemplateDecl *Template, 1617 SourceLocation TemplateLoc, 1618 SourceLocation RAngleLoc, 1619 TemplateArgumentListBuilder &Converted) { 1620 // Check template type parameters. 1621 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) 1622 return CheckTemplateTypeArgument(TTP, Arg, Converted); 1623 1624 // Check non-type template parameters. 1625 if (NonTypeTemplateParmDecl *NTTP =dyn_cast<NonTypeTemplateParmDecl>(Param)) { 1626 // Do substitution on the type of the non-type template parameter 1627 // with the template arguments we've seen thus far. 1628 QualType NTTPType = NTTP->getType(); 1629 if (NTTPType->isDependentType()) { 1630 // Do substitution on the type of the non-type template parameter. 1631 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 1632 NTTP, Converted.getFlatArguments(), 1633 Converted.flatSize(), 1634 SourceRange(TemplateLoc, RAngleLoc)); 1635 1636 TemplateArgumentList TemplateArgs(Context, Converted, 1637 /*TakeArgs=*/false); 1638 NTTPType = SubstType(NTTPType, 1639 MultiLevelTemplateArgumentList(TemplateArgs), 1640 NTTP->getLocation(), 1641 NTTP->getDeclName()); 1642 // If that worked, check the non-type template parameter type 1643 // for validity. 1644 if (!NTTPType.isNull()) 1645 NTTPType = CheckNonTypeTemplateParameterType(NTTPType, 1646 NTTP->getLocation()); 1647 if (NTTPType.isNull()) 1648 return true; 1649 } 1650 1651 switch (Arg.getArgument().getKind()) { 1652 case TemplateArgument::Null: 1653 assert(false && "Should never see a NULL template argument here"); 1654 return true; 1655 1656 case TemplateArgument::Expression: { 1657 Expr *E = Arg.getArgument().getAsExpr(); 1658 TemplateArgument Result; 1659 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 1660 return true; 1661 1662 Converted.Append(Result); 1663 break; 1664 } 1665 1666 case TemplateArgument::Declaration: 1667 case TemplateArgument::Integral: 1668 // We've already checked this template argument, so just copy 1669 // it to the list of converted arguments. 1670 Converted.Append(Arg.getArgument()); 1671 break; 1672 1673 case TemplateArgument::Template: 1674 // We were given a template template argument. It may not be ill-formed; 1675 // see below. 1676 if (DependentTemplateName *DTN 1677 = Arg.getArgument().getAsTemplate().getAsDependentTemplateName()) { 1678 // We have a template argument such as \c T::template X, which we 1679 // parsed as a template template argument. However, since we now 1680 // know that we need a non-type template argument, convert this 1681 // template name into an expression. 1682 Expr *E = new (Context) UnresolvedDeclRefExpr(DTN->getIdentifier(), 1683 Context.DependentTy, 1684 Arg.getTemplateNameLoc(), 1685 Arg.getTemplateQualifierRange(), 1686 DTN->getQualifier(), 1687 /*isAddressOfOperand=*/false); 1688 1689 TemplateArgument Result; 1690 if (CheckTemplateArgument(NTTP, NTTPType, E, Result)) 1691 return true; 1692 1693 Converted.Append(Result); 1694 break; 1695 } 1696 1697 // We have a template argument that actually does refer to a class 1698 // template, template alias, or template template parameter, and 1699 // therefore cannot be a non-type template argument. 1700 Diag(Arg.getLocation(), diag::err_template_arg_must_be_expr) 1701 << Arg.getSourceRange(); 1702 1703 Diag(Param->getLocation(), diag::note_template_param_here); 1704 return true; 1705 1706 case TemplateArgument::Type: { 1707 // We have a non-type template parameter but the template 1708 // argument is a type. 1709 1710 // C++ [temp.arg]p2: 1711 // In a template-argument, an ambiguity between a type-id and 1712 // an expression is resolved to a type-id, regardless of the 1713 // form of the corresponding template-parameter. 1714 // 1715 // We warn specifically about this case, since it can be rather 1716 // confusing for users. 1717 QualType T = Arg.getArgument().getAsType(); 1718 SourceRange SR = Arg.getSourceRange(); 1719 if (T->isFunctionType()) 1720 Diag(SR.getBegin(), diag::err_template_arg_nontype_ambig) << SR << T; 1721 else 1722 Diag(SR.getBegin(), diag::err_template_arg_must_be_expr) << SR; 1723 Diag(Param->getLocation(), diag::note_template_param_here); 1724 return true; 1725 } 1726 1727 case TemplateArgument::Pack: 1728 llvm::llvm_unreachable("Caller must expand template argument packs"); 1729 break; 1730 } 1731 1732 return false; 1733 } 1734 1735 1736 // Check template template parameters. 1737 TemplateTemplateParmDecl *TempParm = cast<TemplateTemplateParmDecl>(Param); 1738 1739 // Substitute into the template parameter list of the template 1740 // template parameter, since previously-supplied template arguments 1741 // may appear within the template template parameter. 1742 { 1743 // Set up a template instantiation context. 1744 LocalInstantiationScope Scope(*this); 1745 InstantiatingTemplate Inst(*this, TemplateLoc, Template, 1746 TempParm, Converted.getFlatArguments(), 1747 Converted.flatSize(), 1748 SourceRange(TemplateLoc, RAngleLoc)); 1749 1750 TemplateArgumentList TemplateArgs(Context, Converted, 1751 /*TakeArgs=*/false); 1752 TempParm = cast_or_null<TemplateTemplateParmDecl>( 1753 SubstDecl(TempParm, CurContext, 1754 MultiLevelTemplateArgumentList(TemplateArgs))); 1755 if (!TempParm) 1756 return true; 1757 1758 // FIXME: TempParam is leaked. 1759 } 1760 1761 switch (Arg.getArgument().getKind()) { 1762 case TemplateArgument::Null: 1763 assert(false && "Should never see a NULL template argument here"); 1764 return true; 1765 1766 case TemplateArgument::Template: 1767 if (CheckTemplateArgument(TempParm, Arg)) 1768 return true; 1769 1770 Converted.Append(Arg.getArgument()); 1771 break; 1772 1773 case TemplateArgument::Expression: 1774 case TemplateArgument::Type: 1775 // We have a template template parameter but the template 1776 // argument does not refer to a template. 1777 Diag(Arg.getLocation(), diag::err_template_arg_must_be_template); 1778 return true; 1779 1780 case TemplateArgument::Declaration: 1781 llvm::llvm_unreachable( 1782 "Declaration argument with template template parameter"); 1783 break; 1784 case TemplateArgument::Integral: 1785 llvm::llvm_unreachable( 1786 "Integral argument with template template parameter"); 1787 break; 1788 1789 case TemplateArgument::Pack: 1790 llvm::llvm_unreachable("Caller must expand template argument packs"); 1791 break; 1792 } 1793 1794 return false; 1795} 1796 1797/// \brief Check that the given template argument list is well-formed 1798/// for specializing the given template. 1799bool Sema::CheckTemplateArgumentList(TemplateDecl *Template, 1800 SourceLocation TemplateLoc, 1801 SourceLocation LAngleLoc, 1802 const TemplateArgumentLoc *TemplateArgs, 1803 unsigned NumTemplateArgs, 1804 SourceLocation RAngleLoc, 1805 bool PartialTemplateArgs, 1806 TemplateArgumentListBuilder &Converted) { 1807 TemplateParameterList *Params = Template->getTemplateParameters(); 1808 unsigned NumParams = Params->size(); 1809 unsigned NumArgs = NumTemplateArgs; 1810 bool Invalid = false; 1811 1812 bool HasParameterPack = 1813 NumParams > 0 && Params->getParam(NumParams - 1)->isTemplateParameterPack(); 1814 1815 if ((NumArgs > NumParams && !HasParameterPack) || 1816 (NumArgs < Params->getMinRequiredArguments() && 1817 !PartialTemplateArgs)) { 1818 // FIXME: point at either the first arg beyond what we can handle, 1819 // or the '>', depending on whether we have too many or too few 1820 // arguments. 1821 SourceRange Range; 1822 if (NumArgs > NumParams) 1823 Range = SourceRange(TemplateArgs[NumParams].getLocation(), RAngleLoc); 1824 Diag(TemplateLoc, diag::err_template_arg_list_different_arity) 1825 << (NumArgs > NumParams) 1826 << (isa<ClassTemplateDecl>(Template)? 0 : 1827 isa<FunctionTemplateDecl>(Template)? 1 : 1828 isa<TemplateTemplateParmDecl>(Template)? 2 : 3) 1829 << Template << Range; 1830 Diag(Template->getLocation(), diag::note_template_decl_here) 1831 << Params->getSourceRange(); 1832 Invalid = true; 1833 } 1834 1835 // C++ [temp.arg]p1: 1836 // [...] The type and form of each template-argument specified in 1837 // a template-id shall match the type and form specified for the 1838 // corresponding parameter declared by the template in its 1839 // template-parameter-list. 1840 unsigned ArgIdx = 0; 1841 for (TemplateParameterList::iterator Param = Params->begin(), 1842 ParamEnd = Params->end(); 1843 Param != ParamEnd; ++Param, ++ArgIdx) { 1844 if (ArgIdx > NumArgs && PartialTemplateArgs) 1845 break; 1846 1847 // If we have a template parameter pack, check every remaining template 1848 // argument against that template parameter pack. 1849 if ((*Param)->isTemplateParameterPack()) { 1850 Converted.BeginPack(); 1851 for (; ArgIdx < NumArgs; ++ArgIdx) { 1852 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 1853 TemplateLoc, RAngleLoc, Converted)) { 1854 Invalid = true; 1855 break; 1856 } 1857 } 1858 Converted.EndPack(); 1859 continue; 1860 } 1861 1862 if (ArgIdx < NumArgs) { 1863 // Check the template argument we were given. 1864 if (CheckTemplateArgument(*Param, TemplateArgs[ArgIdx], Template, 1865 TemplateLoc, RAngleLoc, Converted)) 1866 return true; 1867 1868 continue; 1869 } 1870 1871 // We have a default template argument that we will use. 1872 TemplateArgumentLoc Arg; 1873 1874 // Retrieve the default template argument from the template 1875 // parameter. For each kind of template parameter, we substitute the 1876 // template arguments provided thus far and any "outer" template arguments 1877 // (when the template parameter was part of a nested template) into 1878 // the default argument. 1879 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(*Param)) { 1880 if (!TTP->hasDefaultArgument()) { 1881 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 1882 break; 1883 } 1884 1885 DeclaratorInfo *ArgType = SubstDefaultTemplateArgument(*this, 1886 Template, 1887 TemplateLoc, 1888 RAngleLoc, 1889 TTP, 1890 Converted); 1891 if (!ArgType) 1892 return true; 1893 1894 Arg = TemplateArgumentLoc(TemplateArgument(ArgType->getType()), 1895 ArgType); 1896 } else if (NonTypeTemplateParmDecl *NTTP 1897 = dyn_cast<NonTypeTemplateParmDecl>(*Param)) { 1898 if (!NTTP->hasDefaultArgument()) { 1899 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 1900 break; 1901 } 1902 1903 Sema::OwningExprResult E = SubstDefaultTemplateArgument(*this, Template, 1904 TemplateLoc, 1905 RAngleLoc, 1906 NTTP, 1907 Converted); 1908 if (E.isInvalid()) 1909 return true; 1910 1911 Expr *Ex = E.takeAs<Expr>(); 1912 Arg = TemplateArgumentLoc(TemplateArgument(Ex), Ex); 1913 } else { 1914 TemplateTemplateParmDecl *TempParm 1915 = cast<TemplateTemplateParmDecl>(*Param); 1916 1917 if (!TempParm->hasDefaultArgument()) { 1918 assert((Invalid || PartialTemplateArgs) && "Missing default argument"); 1919 break; 1920 } 1921 1922 TemplateName Name = SubstDefaultTemplateArgument(*this, Template, 1923 TemplateLoc, 1924 RAngleLoc, 1925 TempParm, 1926 Converted); 1927 if (Name.isNull()) 1928 return true; 1929 1930 Arg = TemplateArgumentLoc(TemplateArgument(Name), 1931 TempParm->getDefaultArgument().getTemplateQualifierRange(), 1932 TempParm->getDefaultArgument().getTemplateNameLoc()); 1933 } 1934 1935 // Introduce an instantiation record that describes where we are using 1936 // the default template argument. 1937 InstantiatingTemplate Instantiating(*this, RAngleLoc, Template, *Param, 1938 Converted.getFlatArguments(), 1939 Converted.flatSize(), 1940 SourceRange(TemplateLoc, RAngleLoc)); 1941 1942 // Check the default template argument. 1943 if (CheckTemplateArgument(*Param, Arg, Template, TemplateLoc, 1944 RAngleLoc, Converted)) 1945 return true; 1946 } 1947 1948 return Invalid; 1949} 1950 1951/// \brief Check a template argument against its corresponding 1952/// template type parameter. 1953/// 1954/// This routine implements the semantics of C++ [temp.arg.type]. It 1955/// returns true if an error occurred, and false otherwise. 1956bool Sema::CheckTemplateArgument(TemplateTypeParmDecl *Param, 1957 DeclaratorInfo *ArgInfo) { 1958 assert(ArgInfo && "invalid DeclaratorInfo"); 1959 QualType Arg = ArgInfo->getType(); 1960 1961 // C++ [temp.arg.type]p2: 1962 // A local type, a type with no linkage, an unnamed type or a type 1963 // compounded from any of these types shall not be used as a 1964 // template-argument for a template type-parameter. 1965 // 1966 // FIXME: Perform the recursive and no-linkage type checks. 1967 const TagType *Tag = 0; 1968 if (const EnumType *EnumT = Arg->getAs<EnumType>()) 1969 Tag = EnumT; 1970 else if (const RecordType *RecordT = Arg->getAs<RecordType>()) 1971 Tag = RecordT; 1972 if (Tag && Tag->getDecl()->getDeclContext()->isFunctionOrMethod()) { 1973 SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange(); 1974 return Diag(SR.getBegin(), diag::err_template_arg_local_type) 1975 << QualType(Tag, 0) << SR; 1976 } else if (Tag && !Tag->getDecl()->getDeclName() && 1977 !Tag->getDecl()->getTypedefForAnonDecl()) { 1978 SourceRange SR = ArgInfo->getTypeLoc().getFullSourceRange(); 1979 Diag(SR.getBegin(), diag::err_template_arg_unnamed_type) << SR; 1980 Diag(Tag->getDecl()->getLocation(), diag::note_template_unnamed_type_here); 1981 return true; 1982 } 1983 1984 return false; 1985} 1986 1987/// \brief Checks whether the given template argument is the address 1988/// of an object or function according to C++ [temp.arg.nontype]p1. 1989bool Sema::CheckTemplateArgumentAddressOfObjectOrFunction(Expr *Arg, 1990 NamedDecl *&Entity) { 1991 bool Invalid = false; 1992 1993 // See through any implicit casts we added to fix the type. 1994 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 1995 Arg = Cast->getSubExpr(); 1996 1997 // C++0x allows nullptr, and there's no further checking to be done for that. 1998 if (Arg->getType()->isNullPtrType()) 1999 return false; 2000 2001 // C++ [temp.arg.nontype]p1: 2002 // 2003 // A template-argument for a non-type, non-template 2004 // template-parameter shall be one of: [...] 2005 // 2006 // -- the address of an object or function with external 2007 // linkage, including function templates and function 2008 // template-ids but excluding non-static class members, 2009 // expressed as & id-expression where the & is optional if 2010 // the name refers to a function or array, or if the 2011 // corresponding template-parameter is a reference; or 2012 DeclRefExpr *DRE = 0; 2013 2014 // Ignore (and complain about) any excess parentheses. 2015 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2016 if (!Invalid) { 2017 Diag(Arg->getSourceRange().getBegin(), 2018 diag::err_template_arg_extra_parens) 2019 << Arg->getSourceRange(); 2020 Invalid = true; 2021 } 2022 2023 Arg = Parens->getSubExpr(); 2024 } 2025 2026 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2027 if (UnOp->getOpcode() == UnaryOperator::AddrOf) 2028 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2029 } else 2030 DRE = dyn_cast<DeclRefExpr>(Arg); 2031 2032 if (!DRE || !isa<ValueDecl>(DRE->getDecl())) 2033 return Diag(Arg->getSourceRange().getBegin(), 2034 diag::err_template_arg_not_object_or_func_form) 2035 << Arg->getSourceRange(); 2036 2037 // Cannot refer to non-static data members 2038 if (FieldDecl *Field = dyn_cast<FieldDecl>(DRE->getDecl())) 2039 return Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_field) 2040 << Field << Arg->getSourceRange(); 2041 2042 // Cannot refer to non-static member functions 2043 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(DRE->getDecl())) 2044 if (!Method->isStatic()) 2045 return Diag(Arg->getSourceRange().getBegin(), 2046 diag::err_template_arg_method) 2047 << Method << Arg->getSourceRange(); 2048 2049 // Functions must have external linkage. 2050 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(DRE->getDecl())) { 2051 if (Func->getStorageClass() == FunctionDecl::Static) { 2052 Diag(Arg->getSourceRange().getBegin(), 2053 diag::err_template_arg_function_not_extern) 2054 << Func << Arg->getSourceRange(); 2055 Diag(Func->getLocation(), diag::note_template_arg_internal_object) 2056 << true; 2057 return true; 2058 } 2059 2060 // Okay: we've named a function with external linkage. 2061 Entity = Func; 2062 return Invalid; 2063 } 2064 2065 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) { 2066 if (!Var->hasGlobalStorage()) { 2067 Diag(Arg->getSourceRange().getBegin(), 2068 diag::err_template_arg_object_not_extern) 2069 << Var << Arg->getSourceRange(); 2070 Diag(Var->getLocation(), diag::note_template_arg_internal_object) 2071 << true; 2072 return true; 2073 } 2074 2075 // Okay: we've named an object with external linkage 2076 Entity = Var; 2077 return Invalid; 2078 } 2079 2080 // We found something else, but we don't know specifically what it is. 2081 Diag(Arg->getSourceRange().getBegin(), 2082 diag::err_template_arg_not_object_or_func) 2083 << Arg->getSourceRange(); 2084 Diag(DRE->getDecl()->getLocation(), 2085 diag::note_template_arg_refers_here); 2086 return true; 2087} 2088 2089/// \brief Checks whether the given template argument is a pointer to 2090/// member constant according to C++ [temp.arg.nontype]p1. 2091bool Sema::CheckTemplateArgumentPointerToMember(Expr *Arg, 2092 TemplateArgument &Converted) { 2093 bool Invalid = false; 2094 2095 // See through any implicit casts we added to fix the type. 2096 while (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Arg)) 2097 Arg = Cast->getSubExpr(); 2098 2099 // C++0x allows nullptr, and there's no further checking to be done for that. 2100 if (Arg->getType()->isNullPtrType()) 2101 return false; 2102 2103 // C++ [temp.arg.nontype]p1: 2104 // 2105 // A template-argument for a non-type, non-template 2106 // template-parameter shall be one of: [...] 2107 // 2108 // -- a pointer to member expressed as described in 5.3.1. 2109 DeclRefExpr *DRE = 0; 2110 2111 // Ignore (and complain about) any excess parentheses. 2112 while (ParenExpr *Parens = dyn_cast<ParenExpr>(Arg)) { 2113 if (!Invalid) { 2114 Diag(Arg->getSourceRange().getBegin(), 2115 diag::err_template_arg_extra_parens) 2116 << Arg->getSourceRange(); 2117 Invalid = true; 2118 } 2119 2120 Arg = Parens->getSubExpr(); 2121 } 2122 2123 // A pointer-to-member constant written &Class::member. 2124 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(Arg)) { 2125 if (UnOp->getOpcode() == UnaryOperator::AddrOf) { 2126 DRE = dyn_cast<DeclRefExpr>(UnOp->getSubExpr()); 2127 if (DRE && !DRE->getQualifier()) 2128 DRE = 0; 2129 } 2130 } 2131 // A constant of pointer-to-member type. 2132 else if ((DRE = dyn_cast<DeclRefExpr>(Arg))) { 2133 if (ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl())) { 2134 if (VD->getType()->isMemberPointerType()) { 2135 if (isa<NonTypeTemplateParmDecl>(VD) || 2136 (isa<VarDecl>(VD) && 2137 Context.getCanonicalType(VD->getType()).isConstQualified())) { 2138 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2139 Converted = TemplateArgument(Arg->Retain()); 2140 else 2141 Converted = TemplateArgument(VD->getCanonicalDecl()); 2142 return Invalid; 2143 } 2144 } 2145 } 2146 2147 DRE = 0; 2148 } 2149 2150 if (!DRE) 2151 return Diag(Arg->getSourceRange().getBegin(), 2152 diag::err_template_arg_not_pointer_to_member_form) 2153 << Arg->getSourceRange(); 2154 2155 if (isa<FieldDecl>(DRE->getDecl()) || isa<CXXMethodDecl>(DRE->getDecl())) { 2156 assert((isa<FieldDecl>(DRE->getDecl()) || 2157 !cast<CXXMethodDecl>(DRE->getDecl())->isStatic()) && 2158 "Only non-static member pointers can make it here"); 2159 2160 // Okay: this is the address of a non-static member, and therefore 2161 // a member pointer constant. 2162 if (Arg->isTypeDependent() || Arg->isValueDependent()) 2163 Converted = TemplateArgument(Arg->Retain()); 2164 else 2165 Converted = TemplateArgument(DRE->getDecl()->getCanonicalDecl()); 2166 return Invalid; 2167 } 2168 2169 // We found something else, but we don't know specifically what it is. 2170 Diag(Arg->getSourceRange().getBegin(), 2171 diag::err_template_arg_not_pointer_to_member_form) 2172 << Arg->getSourceRange(); 2173 Diag(DRE->getDecl()->getLocation(), 2174 diag::note_template_arg_refers_here); 2175 return true; 2176} 2177 2178/// \brief Check a template argument against its corresponding 2179/// non-type template parameter. 2180/// 2181/// This routine implements the semantics of C++ [temp.arg.nontype]. 2182/// It returns true if an error occurred, and false otherwise. \p 2183/// InstantiatedParamType is the type of the non-type template 2184/// parameter after it has been instantiated. 2185/// 2186/// If no error was detected, Converted receives the converted template argument. 2187bool Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param, 2188 QualType InstantiatedParamType, Expr *&Arg, 2189 TemplateArgument &Converted) { 2190 SourceLocation StartLoc = Arg->getSourceRange().getBegin(); 2191 2192 // If either the parameter has a dependent type or the argument is 2193 // type-dependent, there's nothing we can check now. 2194 // FIXME: Add template argument to Converted! 2195 if (InstantiatedParamType->isDependentType() || Arg->isTypeDependent()) { 2196 // FIXME: Produce a cloned, canonical expression? 2197 Converted = TemplateArgument(Arg); 2198 return false; 2199 } 2200 2201 // C++ [temp.arg.nontype]p5: 2202 // The following conversions are performed on each expression used 2203 // as a non-type template-argument. If a non-type 2204 // template-argument cannot be converted to the type of the 2205 // corresponding template-parameter then the program is 2206 // ill-formed. 2207 // 2208 // -- for a non-type template-parameter of integral or 2209 // enumeration type, integral promotions (4.5) and integral 2210 // conversions (4.7) are applied. 2211 QualType ParamType = InstantiatedParamType; 2212 QualType ArgType = Arg->getType(); 2213 if (ParamType->isIntegralType() || ParamType->isEnumeralType()) { 2214 // C++ [temp.arg.nontype]p1: 2215 // A template-argument for a non-type, non-template 2216 // template-parameter shall be one of: 2217 // 2218 // -- an integral constant-expression of integral or enumeration 2219 // type; or 2220 // -- the name of a non-type template-parameter; or 2221 SourceLocation NonConstantLoc; 2222 llvm::APSInt Value; 2223 if (!ArgType->isIntegralType() && !ArgType->isEnumeralType()) { 2224 Diag(Arg->getSourceRange().getBegin(), 2225 diag::err_template_arg_not_integral_or_enumeral) 2226 << ArgType << Arg->getSourceRange(); 2227 Diag(Param->getLocation(), diag::note_template_param_here); 2228 return true; 2229 } else if (!Arg->isValueDependent() && 2230 !Arg->isIntegerConstantExpr(Value, Context, &NonConstantLoc)) { 2231 Diag(NonConstantLoc, diag::err_template_arg_not_ice) 2232 << ArgType << Arg->getSourceRange(); 2233 return true; 2234 } 2235 2236 // FIXME: We need some way to more easily get the unqualified form 2237 // of the types without going all the way to the 2238 // canonical type. 2239 if (Context.getCanonicalType(ParamType).getCVRQualifiers()) 2240 ParamType = Context.getCanonicalType(ParamType).getUnqualifiedType(); 2241 if (Context.getCanonicalType(ArgType).getCVRQualifiers()) 2242 ArgType = Context.getCanonicalType(ArgType).getUnqualifiedType(); 2243 2244 // Try to convert the argument to the parameter's type. 2245 if (Context.hasSameType(ParamType, ArgType)) { 2246 // Okay: no conversion necessary 2247 } else if (IsIntegralPromotion(Arg, ArgType, ParamType) || 2248 !ParamType->isEnumeralType()) { 2249 // This is an integral promotion or conversion. 2250 ImpCastExprToType(Arg, ParamType, CastExpr::CK_IntegralCast); 2251 } else { 2252 // We can't perform this conversion. 2253 Diag(Arg->getSourceRange().getBegin(), 2254 diag::err_template_arg_not_convertible) 2255 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2256 Diag(Param->getLocation(), diag::note_template_param_here); 2257 return true; 2258 } 2259 2260 QualType IntegerType = Context.getCanonicalType(ParamType); 2261 if (const EnumType *Enum = IntegerType->getAs<EnumType>()) 2262 IntegerType = Context.getCanonicalType(Enum->getDecl()->getIntegerType()); 2263 2264 if (!Arg->isValueDependent()) { 2265 // Check that an unsigned parameter does not receive a negative 2266 // value. 2267 if (IntegerType->isUnsignedIntegerType() 2268 && (Value.isSigned() && Value.isNegative())) { 2269 Diag(Arg->getSourceRange().getBegin(), diag::err_template_arg_negative) 2270 << Value.toString(10) << Param->getType() 2271 << Arg->getSourceRange(); 2272 Diag(Param->getLocation(), diag::note_template_param_here); 2273 return true; 2274 } 2275 2276 // Check that we don't overflow the template parameter type. 2277 unsigned AllowedBits = Context.getTypeSize(IntegerType); 2278 if (Value.getActiveBits() > AllowedBits) { 2279 Diag(Arg->getSourceRange().getBegin(), 2280 diag::err_template_arg_too_large) 2281 << Value.toString(10) << Param->getType() 2282 << Arg->getSourceRange(); 2283 Diag(Param->getLocation(), diag::note_template_param_here); 2284 return true; 2285 } 2286 2287 if (Value.getBitWidth() != AllowedBits) 2288 Value.extOrTrunc(AllowedBits); 2289 Value.setIsSigned(IntegerType->isSignedIntegerType()); 2290 } 2291 2292 // Add the value of this argument to the list of converted 2293 // arguments. We use the bitwidth and signedness of the template 2294 // parameter. 2295 if (Arg->isValueDependent()) { 2296 // The argument is value-dependent. Create a new 2297 // TemplateArgument with the converted expression. 2298 Converted = TemplateArgument(Arg); 2299 return false; 2300 } 2301 2302 Converted = TemplateArgument(Value, 2303 ParamType->isEnumeralType() ? ParamType 2304 : IntegerType); 2305 return false; 2306 } 2307 2308 // Handle pointer-to-function, reference-to-function, and 2309 // pointer-to-member-function all in (roughly) the same way. 2310 if (// -- For a non-type template-parameter of type pointer to 2311 // function, only the function-to-pointer conversion (4.3) is 2312 // applied. If the template-argument represents a set of 2313 // overloaded functions (or a pointer to such), the matching 2314 // function is selected from the set (13.4). 2315 // In C++0x, any std::nullptr_t value can be converted. 2316 (ParamType->isPointerType() && 2317 ParamType->getAs<PointerType>()->getPointeeType()->isFunctionType()) || 2318 // -- For a non-type template-parameter of type reference to 2319 // function, no conversions apply. If the template-argument 2320 // represents a set of overloaded functions, the matching 2321 // function is selected from the set (13.4). 2322 (ParamType->isReferenceType() && 2323 ParamType->getAs<ReferenceType>()->getPointeeType()->isFunctionType()) || 2324 // -- For a non-type template-parameter of type pointer to 2325 // member function, no conversions apply. If the 2326 // template-argument represents a set of overloaded member 2327 // functions, the matching member function is selected from 2328 // the set (13.4). 2329 // Again, C++0x allows a std::nullptr_t value. 2330 (ParamType->isMemberPointerType() && 2331 ParamType->getAs<MemberPointerType>()->getPointeeType() 2332 ->isFunctionType())) { 2333 if (Context.hasSameUnqualifiedType(ArgType, 2334 ParamType.getNonReferenceType())) { 2335 // We don't have to do anything: the types already match. 2336 } else if (ArgType->isNullPtrType() && (ParamType->isPointerType() || 2337 ParamType->isMemberPointerType())) { 2338 ArgType = ParamType; 2339 if (ParamType->isMemberPointerType()) 2340 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NullToMemberPointer); 2341 else 2342 ImpCastExprToType(Arg, ParamType, CastExpr::CK_BitCast); 2343 } else if (ArgType->isFunctionType() && ParamType->isPointerType()) { 2344 ArgType = Context.getPointerType(ArgType); 2345 ImpCastExprToType(Arg, ArgType, CastExpr::CK_FunctionToPointerDecay); 2346 } else if (FunctionDecl *Fn 2347 = ResolveAddressOfOverloadedFunction(Arg, ParamType, true)) { 2348 if (DiagnoseUseOfDecl(Fn, Arg->getSourceRange().getBegin())) 2349 return true; 2350 2351 Arg = FixOverloadedFunctionReference(Arg, Fn); 2352 ArgType = Arg->getType(); 2353 if (ArgType->isFunctionType() && ParamType->isPointerType()) { 2354 ArgType = Context.getPointerType(Arg->getType()); 2355 ImpCastExprToType(Arg, ArgType, CastExpr::CK_FunctionToPointerDecay); 2356 } 2357 } 2358 2359 if (!Context.hasSameUnqualifiedType(ArgType, 2360 ParamType.getNonReferenceType())) { 2361 // We can't perform this conversion. 2362 Diag(Arg->getSourceRange().getBegin(), 2363 diag::err_template_arg_not_convertible) 2364 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2365 Diag(Param->getLocation(), diag::note_template_param_here); 2366 return true; 2367 } 2368 2369 if (ParamType->isMemberPointerType()) 2370 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2371 2372 NamedDecl *Entity = 0; 2373 if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity)) 2374 return true; 2375 2376 if (Entity) 2377 Entity = cast<NamedDecl>(Entity->getCanonicalDecl()); 2378 Converted = TemplateArgument(Entity); 2379 return false; 2380 } 2381 2382 if (ParamType->isPointerType()) { 2383 // -- for a non-type template-parameter of type pointer to 2384 // object, qualification conversions (4.4) and the 2385 // array-to-pointer conversion (4.2) are applied. 2386 // C++0x also allows a value of std::nullptr_t. 2387 assert(ParamType->getAs<PointerType>()->getPointeeType()->isObjectType() && 2388 "Only object pointers allowed here"); 2389 2390 if (ArgType->isNullPtrType()) { 2391 ArgType = ParamType; 2392 ImpCastExprToType(Arg, ParamType, CastExpr::CK_BitCast); 2393 } else if (ArgType->isArrayType()) { 2394 ArgType = Context.getArrayDecayedType(ArgType); 2395 ImpCastExprToType(Arg, ArgType, CastExpr::CK_ArrayToPointerDecay); 2396 } 2397 2398 if (IsQualificationConversion(ArgType, ParamType)) { 2399 ArgType = ParamType; 2400 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp); 2401 } 2402 2403 if (!Context.hasSameUnqualifiedType(ArgType, ParamType)) { 2404 // We can't perform this conversion. 2405 Diag(Arg->getSourceRange().getBegin(), 2406 diag::err_template_arg_not_convertible) 2407 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2408 Diag(Param->getLocation(), diag::note_template_param_here); 2409 return true; 2410 } 2411 2412 NamedDecl *Entity = 0; 2413 if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity)) 2414 return true; 2415 2416 if (Entity) 2417 Entity = cast<NamedDecl>(Entity->getCanonicalDecl()); 2418 Converted = TemplateArgument(Entity); 2419 return false; 2420 } 2421 2422 if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) { 2423 // -- For a non-type template-parameter of type reference to 2424 // object, no conversions apply. The type referred to by the 2425 // reference may be more cv-qualified than the (otherwise 2426 // identical) type of the template-argument. The 2427 // template-parameter is bound directly to the 2428 // template-argument, which must be an lvalue. 2429 assert(ParamRefType->getPointeeType()->isObjectType() && 2430 "Only object references allowed here"); 2431 2432 if (!Context.hasSameUnqualifiedType(ParamRefType->getPointeeType(), ArgType)) { 2433 Diag(Arg->getSourceRange().getBegin(), 2434 diag::err_template_arg_no_ref_bind) 2435 << InstantiatedParamType << Arg->getType() 2436 << Arg->getSourceRange(); 2437 Diag(Param->getLocation(), diag::note_template_param_here); 2438 return true; 2439 } 2440 2441 unsigned ParamQuals 2442 = Context.getCanonicalType(ParamType).getCVRQualifiers(); 2443 unsigned ArgQuals = Context.getCanonicalType(ArgType).getCVRQualifiers(); 2444 2445 if ((ParamQuals | ArgQuals) != ParamQuals) { 2446 Diag(Arg->getSourceRange().getBegin(), 2447 diag::err_template_arg_ref_bind_ignores_quals) 2448 << InstantiatedParamType << Arg->getType() 2449 << Arg->getSourceRange(); 2450 Diag(Param->getLocation(), diag::note_template_param_here); 2451 return true; 2452 } 2453 2454 NamedDecl *Entity = 0; 2455 if (CheckTemplateArgumentAddressOfObjectOrFunction(Arg, Entity)) 2456 return true; 2457 2458 Entity = cast<NamedDecl>(Entity->getCanonicalDecl()); 2459 Converted = TemplateArgument(Entity); 2460 return false; 2461 } 2462 2463 // -- For a non-type template-parameter of type pointer to data 2464 // member, qualification conversions (4.4) are applied. 2465 // C++0x allows std::nullptr_t values. 2466 assert(ParamType->isMemberPointerType() && "Only pointers to members remain"); 2467 2468 if (Context.hasSameUnqualifiedType(ParamType, ArgType)) { 2469 // Types match exactly: nothing more to do here. 2470 } else if (ArgType->isNullPtrType()) { 2471 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NullToMemberPointer); 2472 } else if (IsQualificationConversion(ArgType, ParamType)) { 2473 ImpCastExprToType(Arg, ParamType, CastExpr::CK_NoOp); 2474 } else { 2475 // We can't perform this conversion. 2476 Diag(Arg->getSourceRange().getBegin(), 2477 diag::err_template_arg_not_convertible) 2478 << Arg->getType() << InstantiatedParamType << Arg->getSourceRange(); 2479 Diag(Param->getLocation(), diag::note_template_param_here); 2480 return true; 2481 } 2482 2483 return CheckTemplateArgumentPointerToMember(Arg, Converted); 2484} 2485 2486/// \brief Check a template argument against its corresponding 2487/// template template parameter. 2488/// 2489/// This routine implements the semantics of C++ [temp.arg.template]. 2490/// It returns true if an error occurred, and false otherwise. 2491bool Sema::CheckTemplateArgument(TemplateTemplateParmDecl *Param, 2492 const TemplateArgumentLoc &Arg) { 2493 TemplateName Name = Arg.getArgument().getAsTemplate(); 2494 TemplateDecl *Template = Name.getAsTemplateDecl(); 2495 if (!Template) { 2496 // Any dependent template name is fine. 2497 assert(Name.isDependent() && "Non-dependent template isn't a declaration?"); 2498 return false; 2499 } 2500 2501 // C++ [temp.arg.template]p1: 2502 // A template-argument for a template template-parameter shall be 2503 // the name of a class template, expressed as id-expression. Only 2504 // primary class templates are considered when matching the 2505 // template template argument with the corresponding parameter; 2506 // partial specializations are not considered even if their 2507 // parameter lists match that of the template template parameter. 2508 // 2509 // Note that we also allow template template parameters here, which 2510 // will happen when we are dealing with, e.g., class template 2511 // partial specializations. 2512 if (!isa<ClassTemplateDecl>(Template) && 2513 !isa<TemplateTemplateParmDecl>(Template)) { 2514 assert(isa<FunctionTemplateDecl>(Template) && 2515 "Only function templates are possible here"); 2516 Diag(Arg.getLocation(), diag::err_template_arg_not_class_template); 2517 Diag(Template->getLocation(), diag::note_template_arg_refers_here_func) 2518 << Template; 2519 } 2520 2521 return !TemplateParameterListsAreEqual(Template->getTemplateParameters(), 2522 Param->getTemplateParameters(), 2523 true, 2524 TPL_TemplateTemplateArgumentMatch, 2525 Arg.getLocation()); 2526} 2527 2528/// \brief Determine whether the given template parameter lists are 2529/// equivalent. 2530/// 2531/// \param New The new template parameter list, typically written in the 2532/// source code as part of a new template declaration. 2533/// 2534/// \param Old The old template parameter list, typically found via 2535/// name lookup of the template declared with this template parameter 2536/// list. 2537/// 2538/// \param Complain If true, this routine will produce a diagnostic if 2539/// the template parameter lists are not equivalent. 2540/// 2541/// \param Kind describes how we are to match the template parameter lists. 2542/// 2543/// \param TemplateArgLoc If this source location is valid, then we 2544/// are actually checking the template parameter list of a template 2545/// argument (New) against the template parameter list of its 2546/// corresponding template template parameter (Old). We produce 2547/// slightly different diagnostics in this scenario. 2548/// 2549/// \returns True if the template parameter lists are equal, false 2550/// otherwise. 2551bool 2552Sema::TemplateParameterListsAreEqual(TemplateParameterList *New, 2553 TemplateParameterList *Old, 2554 bool Complain, 2555 TemplateParameterListEqualKind Kind, 2556 SourceLocation TemplateArgLoc) { 2557 if (Old->size() != New->size()) { 2558 if (Complain) { 2559 unsigned NextDiag = diag::err_template_param_list_different_arity; 2560 if (TemplateArgLoc.isValid()) { 2561 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 2562 NextDiag = diag::note_template_param_list_different_arity; 2563 } 2564 Diag(New->getTemplateLoc(), NextDiag) 2565 << (New->size() > Old->size()) 2566 << (Kind != TPL_TemplateMatch) 2567 << SourceRange(New->getTemplateLoc(), New->getRAngleLoc()); 2568 Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration) 2569 << (Kind != TPL_TemplateMatch) 2570 << SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc()); 2571 } 2572 2573 return false; 2574 } 2575 2576 for (TemplateParameterList::iterator OldParm = Old->begin(), 2577 OldParmEnd = Old->end(), NewParm = New->begin(); 2578 OldParm != OldParmEnd; ++OldParm, ++NewParm) { 2579 if ((*OldParm)->getKind() != (*NewParm)->getKind()) { 2580 if (Complain) { 2581 unsigned NextDiag = diag::err_template_param_different_kind; 2582 if (TemplateArgLoc.isValid()) { 2583 Diag(TemplateArgLoc, diag::err_template_arg_template_params_mismatch); 2584 NextDiag = diag::note_template_param_different_kind; 2585 } 2586 Diag((*NewParm)->getLocation(), NextDiag) 2587 << (Kind != TPL_TemplateMatch); 2588 Diag((*OldParm)->getLocation(), diag::note_template_prev_declaration) 2589 << (Kind != TPL_TemplateMatch); 2590 } 2591 return false; 2592 } 2593 2594 if (isa<TemplateTypeParmDecl>(*OldParm)) { 2595 // Okay; all template type parameters are equivalent (since we 2596 // know we're at the same index). 2597 } else if (NonTypeTemplateParmDecl *OldNTTP 2598 = dyn_cast<NonTypeTemplateParmDecl>(*OldParm)) { 2599 // The types of non-type template parameters must agree. 2600 NonTypeTemplateParmDecl *NewNTTP 2601 = cast<NonTypeTemplateParmDecl>(*NewParm); 2602 2603 // If we are matching a template template argument to a template 2604 // template parameter and one of the non-type template parameter types 2605 // is dependent, then we must wait until template instantiation time 2606 // to actually compare the arguments. 2607 if (Kind == TPL_TemplateTemplateArgumentMatch && 2608 (OldNTTP->getType()->isDependentType() || 2609 NewNTTP->getType()->isDependentType())) 2610 continue; 2611 2612 if (Context.getCanonicalType(OldNTTP->getType()) != 2613 Context.getCanonicalType(NewNTTP->getType())) { 2614 if (Complain) { 2615 unsigned NextDiag = diag::err_template_nontype_parm_different_type; 2616 if (TemplateArgLoc.isValid()) { 2617 Diag(TemplateArgLoc, 2618 diag::err_template_arg_template_params_mismatch); 2619 NextDiag = diag::note_template_nontype_parm_different_type; 2620 } 2621 Diag(NewNTTP->getLocation(), NextDiag) 2622 << NewNTTP->getType() 2623 << (Kind != TPL_TemplateMatch); 2624 Diag(OldNTTP->getLocation(), 2625 diag::note_template_nontype_parm_prev_declaration) 2626 << OldNTTP->getType(); 2627 } 2628 return false; 2629 } 2630 } else { 2631 // The template parameter lists of template template 2632 // parameters must agree. 2633 assert(isa<TemplateTemplateParmDecl>(*OldParm) && 2634 "Only template template parameters handled here"); 2635 TemplateTemplateParmDecl *OldTTP 2636 = cast<TemplateTemplateParmDecl>(*OldParm); 2637 TemplateTemplateParmDecl *NewTTP 2638 = cast<TemplateTemplateParmDecl>(*NewParm); 2639 if (!TemplateParameterListsAreEqual(NewTTP->getTemplateParameters(), 2640 OldTTP->getTemplateParameters(), 2641 Complain, 2642 (Kind == TPL_TemplateMatch? TPL_TemplateTemplateParmMatch : Kind), 2643 TemplateArgLoc)) 2644 return false; 2645 } 2646 } 2647 2648 return true; 2649} 2650 2651/// \brief Check whether a template can be declared within this scope. 2652/// 2653/// If the template declaration is valid in this scope, returns 2654/// false. Otherwise, issues a diagnostic and returns true. 2655bool 2656Sema::CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams) { 2657 // Find the nearest enclosing declaration scope. 2658 while ((S->getFlags() & Scope::DeclScope) == 0 || 2659 (S->getFlags() & Scope::TemplateParamScope) != 0) 2660 S = S->getParent(); 2661 2662 // C++ [temp]p2: 2663 // A template-declaration can appear only as a namespace scope or 2664 // class scope declaration. 2665 DeclContext *Ctx = static_cast<DeclContext *>(S->getEntity()); 2666 if (Ctx && isa<LinkageSpecDecl>(Ctx) && 2667 cast<LinkageSpecDecl>(Ctx)->getLanguage() != LinkageSpecDecl::lang_cxx) 2668 return Diag(TemplateParams->getTemplateLoc(), diag::err_template_linkage) 2669 << TemplateParams->getSourceRange(); 2670 2671 while (Ctx && isa<LinkageSpecDecl>(Ctx)) 2672 Ctx = Ctx->getParent(); 2673 2674 if (Ctx && (Ctx->isFileContext() || Ctx->isRecord())) 2675 return false; 2676 2677 return Diag(TemplateParams->getTemplateLoc(), 2678 diag::err_template_outside_namespace_or_class_scope) 2679 << TemplateParams->getSourceRange(); 2680} 2681 2682/// \brief Determine what kind of template specialization the given declaration 2683/// is. 2684static TemplateSpecializationKind getTemplateSpecializationKind(NamedDecl *D) { 2685 if (!D) 2686 return TSK_Undeclared; 2687 2688 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) 2689 return Record->getTemplateSpecializationKind(); 2690 if (FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) 2691 return Function->getTemplateSpecializationKind(); 2692 if (VarDecl *Var = dyn_cast<VarDecl>(D)) 2693 return Var->getTemplateSpecializationKind(); 2694 2695 return TSK_Undeclared; 2696} 2697 2698/// \brief Check whether a specialization is well-formed in the current 2699/// context. 2700/// 2701/// This routine determines whether a template specialization can be declared 2702/// in the current context (C++ [temp.expl.spec]p2). 2703/// 2704/// \param S the semantic analysis object for which this check is being 2705/// performed. 2706/// 2707/// \param Specialized the entity being specialized or instantiated, which 2708/// may be a kind of template (class template, function template, etc.) or 2709/// a member of a class template (member function, static data member, 2710/// member class). 2711/// 2712/// \param PrevDecl the previous declaration of this entity, if any. 2713/// 2714/// \param Loc the location of the explicit specialization or instantiation of 2715/// this entity. 2716/// 2717/// \param IsPartialSpecialization whether this is a partial specialization of 2718/// a class template. 2719/// 2720/// \returns true if there was an error that we cannot recover from, false 2721/// otherwise. 2722static bool CheckTemplateSpecializationScope(Sema &S, 2723 NamedDecl *Specialized, 2724 NamedDecl *PrevDecl, 2725 SourceLocation Loc, 2726 bool IsPartialSpecialization) { 2727 // Keep these "kind" numbers in sync with the %select statements in the 2728 // various diagnostics emitted by this routine. 2729 int EntityKind = 0; 2730 bool isTemplateSpecialization = false; 2731 if (isa<ClassTemplateDecl>(Specialized)) { 2732 EntityKind = IsPartialSpecialization? 1 : 0; 2733 isTemplateSpecialization = true; 2734 } else if (isa<FunctionTemplateDecl>(Specialized)) { 2735 EntityKind = 2; 2736 isTemplateSpecialization = true; 2737 } else if (isa<CXXMethodDecl>(Specialized)) 2738 EntityKind = 3; 2739 else if (isa<VarDecl>(Specialized)) 2740 EntityKind = 4; 2741 else if (isa<RecordDecl>(Specialized)) 2742 EntityKind = 5; 2743 else { 2744 S.Diag(Loc, diag::err_template_spec_unknown_kind); 2745 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 2746 return true; 2747 } 2748 2749 // C++ [temp.expl.spec]p2: 2750 // An explicit specialization shall be declared in the namespace 2751 // of which the template is a member, or, for member templates, in 2752 // the namespace of which the enclosing class or enclosing class 2753 // template is a member. An explicit specialization of a member 2754 // function, member class or static data member of a class 2755 // template shall be declared in the namespace of which the class 2756 // template is a member. Such a declaration may also be a 2757 // definition. If the declaration is not a definition, the 2758 // specialization may be defined later in the name- space in which 2759 // the explicit specialization was declared, or in a namespace 2760 // that encloses the one in which the explicit specialization was 2761 // declared. 2762 if (S.CurContext->getLookupContext()->isFunctionOrMethod()) { 2763 S.Diag(Loc, diag::err_template_spec_decl_function_scope) 2764 << Specialized; 2765 return true; 2766 } 2767 2768 if (S.CurContext->isRecord() && !IsPartialSpecialization) { 2769 S.Diag(Loc, diag::err_template_spec_decl_class_scope) 2770 << Specialized; 2771 return true; 2772 } 2773 2774 // C++ [temp.class.spec]p6: 2775 // A class template partial specialization may be declared or redeclared 2776 // in any namespace scope in which its definition may be defined (14.5.1 2777 // and 14.5.2). 2778 bool ComplainedAboutScope = false; 2779 DeclContext *SpecializedContext 2780 = Specialized->getDeclContext()->getEnclosingNamespaceContext(); 2781 DeclContext *DC = S.CurContext->getEnclosingNamespaceContext(); 2782 if ((!PrevDecl || 2783 getTemplateSpecializationKind(PrevDecl) == TSK_Undeclared || 2784 getTemplateSpecializationKind(PrevDecl) == TSK_ImplicitInstantiation)){ 2785 // There is no prior declaration of this entity, so this 2786 // specialization must be in the same context as the template 2787 // itself. 2788 if (!DC->Equals(SpecializedContext)) { 2789 if (isa<TranslationUnitDecl>(SpecializedContext)) 2790 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope_global) 2791 << EntityKind << Specialized; 2792 else if (isa<NamespaceDecl>(SpecializedContext)) 2793 S.Diag(Loc, diag::err_template_spec_decl_out_of_scope) 2794 << EntityKind << Specialized 2795 << cast<NamedDecl>(SpecializedContext); 2796 2797 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 2798 ComplainedAboutScope = true; 2799 } 2800 } 2801 2802 // Make sure that this redeclaration (or definition) occurs in an enclosing 2803 // namespace. 2804 // Note that HandleDeclarator() performs this check for explicit 2805 // specializations of function templates, static data members, and member 2806 // functions, so we skip the check here for those kinds of entities. 2807 // FIXME: HandleDeclarator's diagnostics aren't quite as good, though. 2808 // Should we refactor that check, so that it occurs later? 2809 if (!ComplainedAboutScope && !DC->Encloses(SpecializedContext) && 2810 !(isa<FunctionTemplateDecl>(Specialized) || isa<VarDecl>(Specialized) || 2811 isa<FunctionDecl>(Specialized))) { 2812 if (isa<TranslationUnitDecl>(SpecializedContext)) 2813 S.Diag(Loc, diag::err_template_spec_redecl_global_scope) 2814 << EntityKind << Specialized; 2815 else if (isa<NamespaceDecl>(SpecializedContext)) 2816 S.Diag(Loc, diag::err_template_spec_redecl_out_of_scope) 2817 << EntityKind << Specialized 2818 << cast<NamedDecl>(SpecializedContext); 2819 2820 S.Diag(Specialized->getLocation(), diag::note_specialized_entity); 2821 } 2822 2823 // FIXME: check for specialization-after-instantiation errors and such. 2824 2825 return false; 2826} 2827 2828/// \brief Check the non-type template arguments of a class template 2829/// partial specialization according to C++ [temp.class.spec]p9. 2830/// 2831/// \param TemplateParams the template parameters of the primary class 2832/// template. 2833/// 2834/// \param TemplateArg the template arguments of the class template 2835/// partial specialization. 2836/// 2837/// \param MirrorsPrimaryTemplate will be set true if the class 2838/// template partial specialization arguments are identical to the 2839/// implicit template arguments of the primary template. This is not 2840/// necessarily an error (C++0x), and it is left to the caller to diagnose 2841/// this condition when it is an error. 2842/// 2843/// \returns true if there was an error, false otherwise. 2844bool Sema::CheckClassTemplatePartialSpecializationArgs( 2845 TemplateParameterList *TemplateParams, 2846 const TemplateArgumentListBuilder &TemplateArgs, 2847 bool &MirrorsPrimaryTemplate) { 2848 // FIXME: the interface to this function will have to change to 2849 // accommodate variadic templates. 2850 MirrorsPrimaryTemplate = true; 2851 2852 const TemplateArgument *ArgList = TemplateArgs.getFlatArguments(); 2853 2854 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 2855 // Determine whether the template argument list of the partial 2856 // specialization is identical to the implicit argument list of 2857 // the primary template. The caller may need to diagnostic this as 2858 // an error per C++ [temp.class.spec]p9b3. 2859 if (MirrorsPrimaryTemplate) { 2860 if (TemplateTypeParmDecl *TTP 2861 = dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(I))) { 2862 if (Context.getCanonicalType(Context.getTypeDeclType(TTP)) != 2863 Context.getCanonicalType(ArgList[I].getAsType())) 2864 MirrorsPrimaryTemplate = false; 2865 } else if (TemplateTemplateParmDecl *TTP 2866 = dyn_cast<TemplateTemplateParmDecl>( 2867 TemplateParams->getParam(I))) { 2868 TemplateName Name = ArgList[I].getAsTemplate(); 2869 TemplateTemplateParmDecl *ArgDecl 2870 = dyn_cast_or_null<TemplateTemplateParmDecl>(Name.getAsTemplateDecl()); 2871 if (!ArgDecl || 2872 ArgDecl->getIndex() != TTP->getIndex() || 2873 ArgDecl->getDepth() != TTP->getDepth()) 2874 MirrorsPrimaryTemplate = false; 2875 } 2876 } 2877 2878 NonTypeTemplateParmDecl *Param 2879 = dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(I)); 2880 if (!Param) { 2881 continue; 2882 } 2883 2884 Expr *ArgExpr = ArgList[I].getAsExpr(); 2885 if (!ArgExpr) { 2886 MirrorsPrimaryTemplate = false; 2887 continue; 2888 } 2889 2890 // C++ [temp.class.spec]p8: 2891 // A non-type argument is non-specialized if it is the name of a 2892 // non-type parameter. All other non-type arguments are 2893 // specialized. 2894 // 2895 // Below, we check the two conditions that only apply to 2896 // specialized non-type arguments, so skip any non-specialized 2897 // arguments. 2898 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ArgExpr)) 2899 if (NonTypeTemplateParmDecl *NTTP 2900 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl())) { 2901 if (MirrorsPrimaryTemplate && 2902 (Param->getIndex() != NTTP->getIndex() || 2903 Param->getDepth() != NTTP->getDepth())) 2904 MirrorsPrimaryTemplate = false; 2905 2906 continue; 2907 } 2908 2909 // C++ [temp.class.spec]p9: 2910 // Within the argument list of a class template partial 2911 // specialization, the following restrictions apply: 2912 // -- A partially specialized non-type argument expression 2913 // shall not involve a template parameter of the partial 2914 // specialization except when the argument expression is a 2915 // simple identifier. 2916 if (ArgExpr->isTypeDependent() || ArgExpr->isValueDependent()) { 2917 Diag(ArgExpr->getLocStart(), 2918 diag::err_dependent_non_type_arg_in_partial_spec) 2919 << ArgExpr->getSourceRange(); 2920 return true; 2921 } 2922 2923 // -- The type of a template parameter corresponding to a 2924 // specialized non-type argument shall not be dependent on a 2925 // parameter of the specialization. 2926 if (Param->getType()->isDependentType()) { 2927 Diag(ArgExpr->getLocStart(), 2928 diag::err_dependent_typed_non_type_arg_in_partial_spec) 2929 << Param->getType() 2930 << ArgExpr->getSourceRange(); 2931 Diag(Param->getLocation(), diag::note_template_param_here); 2932 return true; 2933 } 2934 2935 MirrorsPrimaryTemplate = false; 2936 } 2937 2938 return false; 2939} 2940 2941Sema::DeclResult 2942Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec, 2943 TagUseKind TUK, 2944 SourceLocation KWLoc, 2945 const CXXScopeSpec &SS, 2946 TemplateTy TemplateD, 2947 SourceLocation TemplateNameLoc, 2948 SourceLocation LAngleLoc, 2949 ASTTemplateArgsPtr TemplateArgsIn, 2950 SourceLocation RAngleLoc, 2951 AttributeList *Attr, 2952 MultiTemplateParamsArg TemplateParameterLists) { 2953 assert(TUK != TUK_Reference && "References are not specializations"); 2954 2955 // Find the class template we're specializing 2956 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 2957 ClassTemplateDecl *ClassTemplate 2958 = dyn_cast_or_null<ClassTemplateDecl>(Name.getAsTemplateDecl()); 2959 2960 if (!ClassTemplate) { 2961 Diag(TemplateNameLoc, diag::err_not_class_template_specialization) 2962 << (Name.getAsTemplateDecl() && 2963 isa<TemplateTemplateParmDecl>(Name.getAsTemplateDecl())); 2964 return true; 2965 } 2966 2967 bool isExplicitSpecialization = false; 2968 bool isPartialSpecialization = false; 2969 2970 // Check the validity of the template headers that introduce this 2971 // template. 2972 // FIXME: We probably shouldn't complain about these headers for 2973 // friend declarations. 2974 TemplateParameterList *TemplateParams 2975 = MatchTemplateParametersToScopeSpecifier(TemplateNameLoc, SS, 2976 (TemplateParameterList**)TemplateParameterLists.get(), 2977 TemplateParameterLists.size(), 2978 isExplicitSpecialization); 2979 if (TemplateParams && TemplateParams->size() > 0) { 2980 isPartialSpecialization = true; 2981 2982 // C++ [temp.class.spec]p10: 2983 // The template parameter list of a specialization shall not 2984 // contain default template argument values. 2985 for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) { 2986 Decl *Param = TemplateParams->getParam(I); 2987 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) { 2988 if (TTP->hasDefaultArgument()) { 2989 Diag(TTP->getDefaultArgumentLoc(), 2990 diag::err_default_arg_in_partial_spec); 2991 TTP->removeDefaultArgument(); 2992 } 2993 } else if (NonTypeTemplateParmDecl *NTTP 2994 = dyn_cast<NonTypeTemplateParmDecl>(Param)) { 2995 if (Expr *DefArg = NTTP->getDefaultArgument()) { 2996 Diag(NTTP->getDefaultArgumentLoc(), 2997 diag::err_default_arg_in_partial_spec) 2998 << DefArg->getSourceRange(); 2999 NTTP->setDefaultArgument(0); 3000 DefArg->Destroy(Context); 3001 } 3002 } else { 3003 TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(Param); 3004 if (TTP->hasDefaultArgument()) { 3005 Diag(TTP->getDefaultArgument().getLocation(), 3006 diag::err_default_arg_in_partial_spec) 3007 << TTP->getDefaultArgument().getSourceRange(); 3008 TTP->setDefaultArgument(TemplateArgumentLoc()); 3009 } 3010 } 3011 } 3012 } else if (TemplateParams) { 3013 if (TUK == TUK_Friend) 3014 Diag(KWLoc, diag::err_template_spec_friend) 3015 << CodeModificationHint::CreateRemoval( 3016 SourceRange(TemplateParams->getTemplateLoc(), 3017 TemplateParams->getRAngleLoc())) 3018 << SourceRange(LAngleLoc, RAngleLoc); 3019 else 3020 isExplicitSpecialization = true; 3021 } else if (TUK != TUK_Friend) { 3022 Diag(KWLoc, diag::err_template_spec_needs_header) 3023 << CodeModificationHint::CreateInsertion(KWLoc, "template<> "); 3024 isExplicitSpecialization = true; 3025 } 3026 3027 // Check that the specialization uses the same tag kind as the 3028 // original template. 3029 TagDecl::TagKind Kind; 3030 switch (TagSpec) { 3031 default: assert(0 && "Unknown tag type!"); 3032 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3033 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3034 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3035 } 3036 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 3037 Kind, KWLoc, 3038 *ClassTemplate->getIdentifier())) { 3039 Diag(KWLoc, diag::err_use_with_wrong_tag) 3040 << ClassTemplate 3041 << CodeModificationHint::CreateReplacement(KWLoc, 3042 ClassTemplate->getTemplatedDecl()->getKindName()); 3043 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 3044 diag::note_previous_use); 3045 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 3046 } 3047 3048 // Translate the parser's template argument list in our AST format. 3049 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 3050 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 3051 3052 // Check that the template argument list is well-formed for this 3053 // template. 3054 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 3055 TemplateArgs.size()); 3056 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, LAngleLoc, 3057 TemplateArgs.data(), TemplateArgs.size(), 3058 RAngleLoc, false, Converted)) 3059 return true; 3060 3061 assert((Converted.structuredSize() == 3062 ClassTemplate->getTemplateParameters()->size()) && 3063 "Converted template argument list is too short!"); 3064 3065 // Find the class template (partial) specialization declaration that 3066 // corresponds to these arguments. 3067 llvm::FoldingSetNodeID ID; 3068 if (isPartialSpecialization) { 3069 bool MirrorsPrimaryTemplate; 3070 if (CheckClassTemplatePartialSpecializationArgs( 3071 ClassTemplate->getTemplateParameters(), 3072 Converted, MirrorsPrimaryTemplate)) 3073 return true; 3074 3075 if (MirrorsPrimaryTemplate) { 3076 // C++ [temp.class.spec]p9b3: 3077 // 3078 // -- The argument list of the specialization shall not be identical 3079 // to the implicit argument list of the primary template. 3080 Diag(TemplateNameLoc, diag::err_partial_spec_args_match_primary_template) 3081 << (TUK == TUK_Definition) 3082 << CodeModificationHint::CreateRemoval(SourceRange(LAngleLoc, 3083 RAngleLoc)); 3084 return CheckClassTemplate(S, TagSpec, TUK, KWLoc, SS, 3085 ClassTemplate->getIdentifier(), 3086 TemplateNameLoc, 3087 Attr, 3088 TemplateParams, 3089 AS_none); 3090 } 3091 3092 // FIXME: Diagnose friend partial specializations 3093 3094 // FIXME: Template parameter list matters, too 3095 ClassTemplatePartialSpecializationDecl::Profile(ID, 3096 Converted.getFlatArguments(), 3097 Converted.flatSize(), 3098 Context); 3099 } else 3100 ClassTemplateSpecializationDecl::Profile(ID, 3101 Converted.getFlatArguments(), 3102 Converted.flatSize(), 3103 Context); 3104 void *InsertPos = 0; 3105 ClassTemplateSpecializationDecl *PrevDecl = 0; 3106 3107 if (isPartialSpecialization) 3108 PrevDecl 3109 = ClassTemplate->getPartialSpecializations().FindNodeOrInsertPos(ID, 3110 InsertPos); 3111 else 3112 PrevDecl 3113 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 3114 3115 ClassTemplateSpecializationDecl *Specialization = 0; 3116 3117 // Check whether we can declare a class template specialization in 3118 // the current scope. 3119 if (TUK != TUK_Friend && 3120 CheckTemplateSpecializationScope(*this, ClassTemplate, PrevDecl, 3121 TemplateNameLoc, 3122 isPartialSpecialization)) 3123 return true; 3124 3125 // The canonical type 3126 QualType CanonType; 3127 if (PrevDecl && 3128 (PrevDecl->getSpecializationKind() == TSK_Undeclared || 3129 TUK == TUK_Friend)) { 3130 // Since the only prior class template specialization with these 3131 // arguments was referenced but not declared, or we're only 3132 // referencing this specialization as a friend, reuse that 3133 // declaration node as our own, updating its source location to 3134 // reflect our new declaration. 3135 Specialization = PrevDecl; 3136 Specialization->setLocation(TemplateNameLoc); 3137 PrevDecl = 0; 3138 CanonType = Context.getTypeDeclType(Specialization); 3139 } else if (isPartialSpecialization) { 3140 // Build the canonical type that describes the converted template 3141 // arguments of the class template partial specialization. 3142 CanonType = Context.getTemplateSpecializationType( 3143 TemplateName(ClassTemplate), 3144 Converted.getFlatArguments(), 3145 Converted.flatSize()); 3146 3147 // Create a new class template partial specialization declaration node. 3148 ClassTemplatePartialSpecializationDecl *PrevPartial 3149 = cast_or_null<ClassTemplatePartialSpecializationDecl>(PrevDecl); 3150 ClassTemplatePartialSpecializationDecl *Partial 3151 = ClassTemplatePartialSpecializationDecl::Create(Context, 3152 ClassTemplate->getDeclContext(), 3153 TemplateNameLoc, 3154 TemplateParams, 3155 ClassTemplate, 3156 Converted, 3157 TemplateArgs.data(), 3158 TemplateArgs.size(), 3159 PrevPartial); 3160 3161 if (PrevPartial) { 3162 ClassTemplate->getPartialSpecializations().RemoveNode(PrevPartial); 3163 ClassTemplate->getPartialSpecializations().GetOrInsertNode(Partial); 3164 } else { 3165 ClassTemplate->getPartialSpecializations().InsertNode(Partial, InsertPos); 3166 } 3167 Specialization = Partial; 3168 3169 // If we are providing an explicit specialization of a member class 3170 // template specialization, make a note of that. 3171 if (PrevPartial && PrevPartial->getInstantiatedFromMember()) 3172 PrevPartial->setMemberSpecialization(); 3173 3174 // Check that all of the template parameters of the class template 3175 // partial specialization are deducible from the template 3176 // arguments. If not, this class template partial specialization 3177 // will never be used. 3178 llvm::SmallVector<bool, 8> DeducibleParams; 3179 DeducibleParams.resize(TemplateParams->size()); 3180 MarkUsedTemplateParameters(Partial->getTemplateArgs(), true, 3181 TemplateParams->getDepth(), 3182 DeducibleParams); 3183 unsigned NumNonDeducible = 0; 3184 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) 3185 if (!DeducibleParams[I]) 3186 ++NumNonDeducible; 3187 3188 if (NumNonDeducible) { 3189 Diag(TemplateNameLoc, diag::warn_partial_specs_not_deducible) 3190 << (NumNonDeducible > 1) 3191 << SourceRange(TemplateNameLoc, RAngleLoc); 3192 for (unsigned I = 0, N = DeducibleParams.size(); I != N; ++I) { 3193 if (!DeducibleParams[I]) { 3194 NamedDecl *Param = cast<NamedDecl>(TemplateParams->getParam(I)); 3195 if (Param->getDeclName()) 3196 Diag(Param->getLocation(), 3197 diag::note_partial_spec_unused_parameter) 3198 << Param->getDeclName(); 3199 else 3200 Diag(Param->getLocation(), 3201 diag::note_partial_spec_unused_parameter) 3202 << std::string("<anonymous>"); 3203 } 3204 } 3205 } 3206 } else { 3207 // Create a new class template specialization declaration node for 3208 // this explicit specialization or friend declaration. 3209 Specialization 3210 = ClassTemplateSpecializationDecl::Create(Context, 3211 ClassTemplate->getDeclContext(), 3212 TemplateNameLoc, 3213 ClassTemplate, 3214 Converted, 3215 PrevDecl); 3216 3217 if (PrevDecl) { 3218 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 3219 ClassTemplate->getSpecializations().GetOrInsertNode(Specialization); 3220 } else { 3221 ClassTemplate->getSpecializations().InsertNode(Specialization, 3222 InsertPos); 3223 } 3224 3225 CanonType = Context.getTypeDeclType(Specialization); 3226 } 3227 3228 // C++ [temp.expl.spec]p6: 3229 // If a template, a member template or the member of a class template is 3230 // explicitly specialized then that specialization shall be declared 3231 // before the first use of that specialization that would cause an implicit 3232 // instantiation to take place, in every translation unit in which such a 3233 // use occurs; no diagnostic is required. 3234 if (PrevDecl && PrevDecl->getPointOfInstantiation().isValid()) { 3235 SourceRange Range(TemplateNameLoc, RAngleLoc); 3236 Diag(TemplateNameLoc, diag::err_specialization_after_instantiation) 3237 << Context.getTypeDeclType(Specialization) << Range; 3238 3239 Diag(PrevDecl->getPointOfInstantiation(), 3240 diag::note_instantiation_required_here) 3241 << (PrevDecl->getTemplateSpecializationKind() 3242 != TSK_ImplicitInstantiation); 3243 return true; 3244 } 3245 3246 // If this is not a friend, note that this is an explicit specialization. 3247 if (TUK != TUK_Friend) 3248 Specialization->setSpecializationKind(TSK_ExplicitSpecialization); 3249 3250 // Check that this isn't a redefinition of this specialization. 3251 if (TUK == TUK_Definition) { 3252 if (RecordDecl *Def = Specialization->getDefinition(Context)) { 3253 SourceRange Range(TemplateNameLoc, RAngleLoc); 3254 Diag(TemplateNameLoc, diag::err_redefinition) 3255 << Context.getTypeDeclType(Specialization) << Range; 3256 Diag(Def->getLocation(), diag::note_previous_definition); 3257 Specialization->setInvalidDecl(); 3258 return true; 3259 } 3260 } 3261 3262 // Build the fully-sugared type for this class template 3263 // specialization as the user wrote in the specialization 3264 // itself. This means that we'll pretty-print the type retrieved 3265 // from the specialization's declaration the way that the user 3266 // actually wrote the specialization, rather than formatting the 3267 // name based on the "canonical" representation used to store the 3268 // template arguments in the specialization. 3269 QualType WrittenTy 3270 = Context.getTemplateSpecializationType(Name, 3271 TemplateArgs.data(), 3272 TemplateArgs.size(), 3273 CanonType); 3274 if (TUK != TUK_Friend) 3275 Specialization->setTypeAsWritten(WrittenTy); 3276 TemplateArgsIn.release(); 3277 3278 // C++ [temp.expl.spec]p9: 3279 // A template explicit specialization is in the scope of the 3280 // namespace in which the template was defined. 3281 // 3282 // We actually implement this paragraph where we set the semantic 3283 // context (in the creation of the ClassTemplateSpecializationDecl), 3284 // but we also maintain the lexical context where the actual 3285 // definition occurs. 3286 Specialization->setLexicalDeclContext(CurContext); 3287 3288 // We may be starting the definition of this specialization. 3289 if (TUK == TUK_Definition) 3290 Specialization->startDefinition(); 3291 3292 if (TUK == TUK_Friend) { 3293 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, 3294 TemplateNameLoc, 3295 WrittenTy.getTypePtr(), 3296 /*FIXME:*/KWLoc); 3297 Friend->setAccess(AS_public); 3298 CurContext->addDecl(Friend); 3299 } else { 3300 // Add the specialization into its lexical context, so that it can 3301 // be seen when iterating through the list of declarations in that 3302 // context. However, specializations are not found by name lookup. 3303 CurContext->addDecl(Specialization); 3304 } 3305 return DeclPtrTy::make(Specialization); 3306} 3307 3308Sema::DeclPtrTy 3309Sema::ActOnTemplateDeclarator(Scope *S, 3310 MultiTemplateParamsArg TemplateParameterLists, 3311 Declarator &D) { 3312 return HandleDeclarator(S, D, move(TemplateParameterLists), false); 3313} 3314 3315Sema::DeclPtrTy 3316Sema::ActOnStartOfFunctionTemplateDef(Scope *FnBodyScope, 3317 MultiTemplateParamsArg TemplateParameterLists, 3318 Declarator &D) { 3319 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3320 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3321 "Not a function declarator!"); 3322 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3323 3324 if (FTI.hasPrototype) { 3325 // FIXME: Diagnose arguments without names in C. 3326 } 3327 3328 Scope *ParentScope = FnBodyScope->getParent(); 3329 3330 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3331 move(TemplateParameterLists), 3332 /*IsFunctionDefinition=*/true); 3333 if (FunctionTemplateDecl *FunctionTemplate 3334 = dyn_cast_or_null<FunctionTemplateDecl>(DP.getAs<Decl>())) 3335 return ActOnStartOfFunctionDef(FnBodyScope, 3336 DeclPtrTy::make(FunctionTemplate->getTemplatedDecl())); 3337 if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(DP.getAs<Decl>())) 3338 return ActOnStartOfFunctionDef(FnBodyScope, DeclPtrTy::make(Function)); 3339 return DeclPtrTy(); 3340} 3341 3342/// \brief Diagnose cases where we have an explicit template specialization 3343/// before/after an explicit template instantiation, producing diagnostics 3344/// for those cases where they are required and determining whether the 3345/// new specialization/instantiation will have any effect. 3346/// 3347/// \param NewLoc the location of the new explicit specialization or 3348/// instantiation. 3349/// 3350/// \param NewTSK the kind of the new explicit specialization or instantiation. 3351/// 3352/// \param PrevDecl the previous declaration of the entity. 3353/// 3354/// \param PrevTSK the kind of the old explicit specialization or instantiatin. 3355/// 3356/// \param PrevPointOfInstantiation if valid, indicates where the previus 3357/// declaration was instantiated (either implicitly or explicitly). 3358/// 3359/// \param SuppressNew will be set to true to indicate that the new 3360/// specialization or instantiation has no effect and should be ignored. 3361/// 3362/// \returns true if there was an error that should prevent the introduction of 3363/// the new declaration into the AST, false otherwise. 3364bool 3365Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc, 3366 TemplateSpecializationKind NewTSK, 3367 NamedDecl *PrevDecl, 3368 TemplateSpecializationKind PrevTSK, 3369 SourceLocation PrevPointOfInstantiation, 3370 bool &SuppressNew) { 3371 SuppressNew = false; 3372 3373 switch (NewTSK) { 3374 case TSK_Undeclared: 3375 case TSK_ImplicitInstantiation: 3376 assert(false && "Don't check implicit instantiations here"); 3377 return false; 3378 3379 case TSK_ExplicitSpecialization: 3380 switch (PrevTSK) { 3381 case TSK_Undeclared: 3382 case TSK_ExplicitSpecialization: 3383 // Okay, we're just specializing something that is either already 3384 // explicitly specialized or has merely been mentioned without any 3385 // instantiation. 3386 return false; 3387 3388 case TSK_ImplicitInstantiation: 3389 if (PrevPointOfInstantiation.isInvalid()) { 3390 // The declaration itself has not actually been instantiated, so it is 3391 // still okay to specialize it. 3392 return false; 3393 } 3394 // Fall through 3395 3396 case TSK_ExplicitInstantiationDeclaration: 3397 case TSK_ExplicitInstantiationDefinition: 3398 assert((PrevTSK == TSK_ImplicitInstantiation || 3399 PrevPointOfInstantiation.isValid()) && 3400 "Explicit instantiation without point of instantiation?"); 3401 3402 // C++ [temp.expl.spec]p6: 3403 // If a template, a member template or the member of a class template 3404 // is explicitly specialized then that specialization shall be declared 3405 // before the first use of that specialization that would cause an 3406 // implicit instantiation to take place, in every translation unit in 3407 // which such a use occurs; no diagnostic is required. 3408 Diag(NewLoc, diag::err_specialization_after_instantiation) 3409 << PrevDecl; 3410 Diag(PrevPointOfInstantiation, diag::note_instantiation_required_here) 3411 << (PrevTSK != TSK_ImplicitInstantiation); 3412 3413 return true; 3414 } 3415 break; 3416 3417 case TSK_ExplicitInstantiationDeclaration: 3418 switch (PrevTSK) { 3419 case TSK_ExplicitInstantiationDeclaration: 3420 // This explicit instantiation declaration is redundant (that's okay). 3421 SuppressNew = true; 3422 return false; 3423 3424 case TSK_Undeclared: 3425 case TSK_ImplicitInstantiation: 3426 // We're explicitly instantiating something that may have already been 3427 // implicitly instantiated; that's fine. 3428 return false; 3429 3430 case TSK_ExplicitSpecialization: 3431 // C++0x [temp.explicit]p4: 3432 // For a given set of template parameters, if an explicit instantiation 3433 // of a template appears after a declaration of an explicit 3434 // specialization for that template, the explicit instantiation has no 3435 // effect. 3436 return false; 3437 3438 case TSK_ExplicitInstantiationDefinition: 3439 // C++0x [temp.explicit]p10: 3440 // If an entity is the subject of both an explicit instantiation 3441 // declaration and an explicit instantiation definition in the same 3442 // translation unit, the definition shall follow the declaration. 3443 Diag(NewLoc, 3444 diag::err_explicit_instantiation_declaration_after_definition); 3445 Diag(PrevPointOfInstantiation, 3446 diag::note_explicit_instantiation_definition_here); 3447 assert(PrevPointOfInstantiation.isValid() && 3448 "Explicit instantiation without point of instantiation?"); 3449 SuppressNew = true; 3450 return false; 3451 } 3452 break; 3453 3454 case TSK_ExplicitInstantiationDefinition: 3455 switch (PrevTSK) { 3456 case TSK_Undeclared: 3457 case TSK_ImplicitInstantiation: 3458 // We're explicitly instantiating something that may have already been 3459 // implicitly instantiated; that's fine. 3460 return false; 3461 3462 case TSK_ExplicitSpecialization: 3463 // C++ DR 259, C++0x [temp.explicit]p4: 3464 // For a given set of template parameters, if an explicit 3465 // instantiation of a template appears after a declaration of 3466 // an explicit specialization for that template, the explicit 3467 // instantiation has no effect. 3468 // 3469 // In C++98/03 mode, we only give an extension warning here, because it 3470 // is not not harmful to try to explicitly instantiate something that 3471 // has been explicitly specialized. 3472 if (!getLangOptions().CPlusPlus0x) { 3473 Diag(NewLoc, diag::ext_explicit_instantiation_after_specialization) 3474 << PrevDecl; 3475 Diag(PrevDecl->getLocation(), 3476 diag::note_previous_template_specialization); 3477 } 3478 SuppressNew = true; 3479 return false; 3480 3481 case TSK_ExplicitInstantiationDeclaration: 3482 // We're explicity instantiating a definition for something for which we 3483 // were previously asked to suppress instantiations. That's fine. 3484 return false; 3485 3486 case TSK_ExplicitInstantiationDefinition: 3487 // C++0x [temp.spec]p5: 3488 // For a given template and a given set of template-arguments, 3489 // - an explicit instantiation definition shall appear at most once 3490 // in a program, 3491 Diag(NewLoc, diag::err_explicit_instantiation_duplicate) 3492 << PrevDecl; 3493 Diag(PrevPointOfInstantiation, 3494 diag::note_previous_explicit_instantiation); 3495 SuppressNew = true; 3496 return false; 3497 } 3498 break; 3499 } 3500 3501 assert(false && "Missing specialization/instantiation case?"); 3502 3503 return false; 3504} 3505 3506/// \brief Perform semantic analysis for the given function template 3507/// specialization. 3508/// 3509/// This routine performs all of the semantic analysis required for an 3510/// explicit function template specialization. On successful completion, 3511/// the function declaration \p FD will become a function template 3512/// specialization. 3513/// 3514/// \param FD the function declaration, which will be updated to become a 3515/// function template specialization. 3516/// 3517/// \param HasExplicitTemplateArgs whether any template arguments were 3518/// explicitly provided. 3519/// 3520/// \param LAngleLoc the location of the left angle bracket ('<'), if 3521/// template arguments were explicitly provided. 3522/// 3523/// \param ExplicitTemplateArgs the explicitly-provided template arguments, 3524/// if any. 3525/// 3526/// \param NumExplicitTemplateArgs the number of explicitly-provided template 3527/// arguments. This number may be zero even when HasExplicitTemplateArgs is 3528/// true as in, e.g., \c void sort<>(char*, char*); 3529/// 3530/// \param RAngleLoc the location of the right angle bracket ('>'), if 3531/// template arguments were explicitly provided. 3532/// 3533/// \param PrevDecl the set of declarations that 3534bool 3535Sema::CheckFunctionTemplateSpecialization(FunctionDecl *FD, 3536 bool HasExplicitTemplateArgs, 3537 SourceLocation LAngleLoc, 3538 const TemplateArgumentLoc *ExplicitTemplateArgs, 3539 unsigned NumExplicitTemplateArgs, 3540 SourceLocation RAngleLoc, 3541 LookupResult &Previous) { 3542 // The set of function template specializations that could match this 3543 // explicit function template specialization. 3544 typedef llvm::SmallVector<FunctionDecl *, 8> CandidateSet; 3545 CandidateSet Candidates; 3546 3547 DeclContext *FDLookupContext = FD->getDeclContext()->getLookupContext(); 3548 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 3549 I != E; ++I) { 3550 NamedDecl *Ovl = (*I)->getUnderlyingDecl(); 3551 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Ovl)) { 3552 // Only consider templates found within the same semantic lookup scope as 3553 // FD. 3554 if (!FDLookupContext->Equals(Ovl->getDeclContext()->getLookupContext())) 3555 continue; 3556 3557 // C++ [temp.expl.spec]p11: 3558 // A trailing template-argument can be left unspecified in the 3559 // template-id naming an explicit function template specialization 3560 // provided it can be deduced from the function argument type. 3561 // Perform template argument deduction to determine whether we may be 3562 // specializing this template. 3563 // FIXME: It is somewhat wasteful to build 3564 TemplateDeductionInfo Info(Context); 3565 FunctionDecl *Specialization = 0; 3566 if (TemplateDeductionResult TDK 3567 = DeduceTemplateArguments(FunTmpl, HasExplicitTemplateArgs, 3568 ExplicitTemplateArgs, 3569 NumExplicitTemplateArgs, 3570 FD->getType(), 3571 Specialization, 3572 Info)) { 3573 // FIXME: Template argument deduction failed; record why it failed, so 3574 // that we can provide nifty diagnostics. 3575 (void)TDK; 3576 continue; 3577 } 3578 3579 // Record this candidate. 3580 Candidates.push_back(Specialization); 3581 } 3582 } 3583 3584 // Find the most specialized function template. 3585 FunctionDecl *Specialization = getMostSpecialized(Candidates.data(), 3586 Candidates.size(), 3587 TPOC_Other, 3588 FD->getLocation(), 3589 PartialDiagnostic(diag::err_function_template_spec_no_match) 3590 << FD->getDeclName(), 3591 PartialDiagnostic(diag::err_function_template_spec_ambiguous) 3592 << FD->getDeclName() << HasExplicitTemplateArgs, 3593 PartialDiagnostic(diag::note_function_template_spec_matched)); 3594 if (!Specialization) 3595 return true; 3596 3597 // FIXME: Check if the prior specialization has a point of instantiation. 3598 // If so, we have run afoul of . 3599 3600 // Check the scope of this explicit specialization. 3601 if (CheckTemplateSpecializationScope(*this, 3602 Specialization->getPrimaryTemplate(), 3603 Specialization, FD->getLocation(), 3604 false)) 3605 return true; 3606 3607 // C++ [temp.expl.spec]p6: 3608 // If a template, a member template or the member of a class template is 3609 // explicitly specialized then that specialization shall be declared 3610 // before the first use of that specialization that would cause an implicit 3611 // instantiation to take place, in every translation unit in which such a 3612 // use occurs; no diagnostic is required. 3613 FunctionTemplateSpecializationInfo *SpecInfo 3614 = Specialization->getTemplateSpecializationInfo(); 3615 assert(SpecInfo && "Function template specialization info missing?"); 3616 if (SpecInfo->getPointOfInstantiation().isValid()) { 3617 Diag(FD->getLocation(), diag::err_specialization_after_instantiation) 3618 << FD; 3619 Diag(SpecInfo->getPointOfInstantiation(), 3620 diag::note_instantiation_required_here) 3621 << (Specialization->getTemplateSpecializationKind() 3622 != TSK_ImplicitInstantiation); 3623 return true; 3624 } 3625 3626 // Mark the prior declaration as an explicit specialization, so that later 3627 // clients know that this is an explicit specialization. 3628 SpecInfo->setTemplateSpecializationKind(TSK_ExplicitSpecialization); 3629 3630 // Turn the given function declaration into a function template 3631 // specialization, with the template arguments from the previous 3632 // specialization. 3633 FD->setFunctionTemplateSpecialization(Context, 3634 Specialization->getPrimaryTemplate(), 3635 new (Context) TemplateArgumentList( 3636 *Specialization->getTemplateSpecializationArgs()), 3637 /*InsertPos=*/0, 3638 TSK_ExplicitSpecialization); 3639 3640 // The "previous declaration" for this function template specialization is 3641 // the prior function template specialization. 3642 Previous.clear(); 3643 Previous.addDecl(Specialization); 3644 return false; 3645} 3646 3647/// \brief Perform semantic analysis for the given non-template member 3648/// specialization. 3649/// 3650/// This routine performs all of the semantic analysis required for an 3651/// explicit member function specialization. On successful completion, 3652/// the function declaration \p FD will become a member function 3653/// specialization. 3654/// 3655/// \param Member the member declaration, which will be updated to become a 3656/// specialization. 3657/// 3658/// \param Previous the set of declarations, one of which may be specialized 3659/// by this function specialization; the set will be modified to contain the 3660/// redeclared member. 3661bool 3662Sema::CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous) { 3663 assert(!isa<TemplateDecl>(Member) && "Only for non-template members"); 3664 3665 // Try to find the member we are instantiating. 3666 NamedDecl *Instantiation = 0; 3667 NamedDecl *InstantiatedFrom = 0; 3668 MemberSpecializationInfo *MSInfo = 0; 3669 3670 if (Previous.empty()) { 3671 // Nowhere to look anyway. 3672 } else if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Member)) { 3673 for (LookupResult::iterator I = Previous.begin(), E = Previous.end(); 3674 I != E; ++I) { 3675 NamedDecl *D = (*I)->getUnderlyingDecl(); 3676 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) { 3677 if (Context.hasSameType(Function->getType(), Method->getType())) { 3678 Instantiation = Method; 3679 InstantiatedFrom = Method->getInstantiatedFromMemberFunction(); 3680 MSInfo = Method->getMemberSpecializationInfo(); 3681 break; 3682 } 3683 } 3684 } 3685 } else if (isa<VarDecl>(Member)) { 3686 VarDecl *PrevVar; 3687 if (Previous.isSingleResult() && 3688 (PrevVar = dyn_cast<VarDecl>(Previous.getFoundDecl()))) 3689 if (PrevVar->isStaticDataMember()) { 3690 Instantiation = PrevVar; 3691 InstantiatedFrom = PrevVar->getInstantiatedFromStaticDataMember(); 3692 MSInfo = PrevVar->getMemberSpecializationInfo(); 3693 } 3694 } else if (isa<RecordDecl>(Member)) { 3695 CXXRecordDecl *PrevRecord; 3696 if (Previous.isSingleResult() && 3697 (PrevRecord = dyn_cast<CXXRecordDecl>(Previous.getFoundDecl()))) { 3698 Instantiation = PrevRecord; 3699 InstantiatedFrom = PrevRecord->getInstantiatedFromMemberClass(); 3700 MSInfo = PrevRecord->getMemberSpecializationInfo(); 3701 } 3702 } 3703 3704 if (!Instantiation) { 3705 // There is no previous declaration that matches. Since member 3706 // specializations are always out-of-line, the caller will complain about 3707 // this mismatch later. 3708 return false; 3709 } 3710 3711 // Make sure that this is a specialization of a member. 3712 if (!InstantiatedFrom) { 3713 Diag(Member->getLocation(), diag::err_spec_member_not_instantiated) 3714 << Member; 3715 Diag(Instantiation->getLocation(), diag::note_specialized_decl); 3716 return true; 3717 } 3718 3719 // C++ [temp.expl.spec]p6: 3720 // If a template, a member template or the member of a class template is 3721 // explicitly specialized then that spe- cialization shall be declared 3722 // before the first use of that specialization that would cause an implicit 3723 // instantiation to take place, in every translation unit in which such a 3724 // use occurs; no diagnostic is required. 3725 assert(MSInfo && "Member specialization info missing?"); 3726 if (MSInfo->getPointOfInstantiation().isValid()) { 3727 Diag(Member->getLocation(), diag::err_specialization_after_instantiation) 3728 << Member; 3729 Diag(MSInfo->getPointOfInstantiation(), 3730 diag::note_instantiation_required_here) 3731 << (MSInfo->getTemplateSpecializationKind() != TSK_ImplicitInstantiation); 3732 return true; 3733 } 3734 3735 // Check the scope of this explicit specialization. 3736 if (CheckTemplateSpecializationScope(*this, 3737 InstantiatedFrom, 3738 Instantiation, Member->getLocation(), 3739 false)) 3740 return true; 3741 3742 // Note that this is an explicit instantiation of a member. 3743 // the original declaration to note that it is an explicit specialization 3744 // (if it was previously an implicit instantiation). This latter step 3745 // makes bookkeeping easier. 3746 if (isa<FunctionDecl>(Member)) { 3747 FunctionDecl *InstantiationFunction = cast<FunctionDecl>(Instantiation); 3748 if (InstantiationFunction->getTemplateSpecializationKind() == 3749 TSK_ImplicitInstantiation) { 3750 InstantiationFunction->setTemplateSpecializationKind( 3751 TSK_ExplicitSpecialization); 3752 InstantiationFunction->setLocation(Member->getLocation()); 3753 } 3754 3755 cast<FunctionDecl>(Member)->setInstantiationOfMemberFunction( 3756 cast<CXXMethodDecl>(InstantiatedFrom), 3757 TSK_ExplicitSpecialization); 3758 } else if (isa<VarDecl>(Member)) { 3759 VarDecl *InstantiationVar = cast<VarDecl>(Instantiation); 3760 if (InstantiationVar->getTemplateSpecializationKind() == 3761 TSK_ImplicitInstantiation) { 3762 InstantiationVar->setTemplateSpecializationKind( 3763 TSK_ExplicitSpecialization); 3764 InstantiationVar->setLocation(Member->getLocation()); 3765 } 3766 3767 Context.setInstantiatedFromStaticDataMember(cast<VarDecl>(Member), 3768 cast<VarDecl>(InstantiatedFrom), 3769 TSK_ExplicitSpecialization); 3770 } else { 3771 assert(isa<CXXRecordDecl>(Member) && "Only member classes remain"); 3772 CXXRecordDecl *InstantiationClass = cast<CXXRecordDecl>(Instantiation); 3773 if (InstantiationClass->getTemplateSpecializationKind() == 3774 TSK_ImplicitInstantiation) { 3775 InstantiationClass->setTemplateSpecializationKind( 3776 TSK_ExplicitSpecialization); 3777 InstantiationClass->setLocation(Member->getLocation()); 3778 } 3779 3780 cast<CXXRecordDecl>(Member)->setInstantiationOfMemberClass( 3781 cast<CXXRecordDecl>(InstantiatedFrom), 3782 TSK_ExplicitSpecialization); 3783 } 3784 3785 // Save the caller the trouble of having to figure out which declaration 3786 // this specialization matches. 3787 Previous.clear(); 3788 Previous.addDecl(Instantiation); 3789 return false; 3790} 3791 3792/// \brief Check the scope of an explicit instantiation. 3793static void CheckExplicitInstantiationScope(Sema &S, NamedDecl *D, 3794 SourceLocation InstLoc, 3795 bool WasQualifiedName) { 3796 DeclContext *ExpectedContext 3797 = D->getDeclContext()->getEnclosingNamespaceContext()->getLookupContext(); 3798 DeclContext *CurContext = S.CurContext->getLookupContext(); 3799 3800 // C++0x [temp.explicit]p2: 3801 // An explicit instantiation shall appear in an enclosing namespace of its 3802 // template. 3803 // 3804 // This is DR275, which we do not retroactively apply to C++98/03. 3805 if (S.getLangOptions().CPlusPlus0x && 3806 !CurContext->Encloses(ExpectedContext)) { 3807 if (NamespaceDecl *NS = dyn_cast<NamespaceDecl>(ExpectedContext)) 3808 S.Diag(InstLoc, diag::err_explicit_instantiation_out_of_scope) 3809 << D << NS; 3810 else 3811 S.Diag(InstLoc, diag::err_explicit_instantiation_must_be_global) 3812 << D; 3813 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 3814 return; 3815 } 3816 3817 // C++0x [temp.explicit]p2: 3818 // If the name declared in the explicit instantiation is an unqualified 3819 // name, the explicit instantiation shall appear in the namespace where 3820 // its template is declared or, if that namespace is inline (7.3.1), any 3821 // namespace from its enclosing namespace set. 3822 if (WasQualifiedName) 3823 return; 3824 3825 if (CurContext->Equals(ExpectedContext)) 3826 return; 3827 3828 S.Diag(InstLoc, diag::err_explicit_instantiation_unqualified_wrong_namespace) 3829 << D << ExpectedContext; 3830 S.Diag(D->getLocation(), diag::note_explicit_instantiation_here); 3831} 3832 3833/// \brief Determine whether the given scope specifier has a template-id in it. 3834static bool ScopeSpecifierHasTemplateId(const CXXScopeSpec &SS) { 3835 if (!SS.isSet()) 3836 return false; 3837 3838 // C++0x [temp.explicit]p2: 3839 // If the explicit instantiation is for a member function, a member class 3840 // or a static data member of a class template specialization, the name of 3841 // the class template specialization in the qualified-id for the member 3842 // name shall be a simple-template-id. 3843 // 3844 // C++98 has the same restriction, just worded differently. 3845 for (NestedNameSpecifier *NNS = (NestedNameSpecifier *)SS.getScopeRep(); 3846 NNS; NNS = NNS->getPrefix()) 3847 if (Type *T = NNS->getAsType()) 3848 if (isa<TemplateSpecializationType>(T)) 3849 return true; 3850 3851 return false; 3852} 3853 3854// Explicit instantiation of a class template specialization 3855// FIXME: Implement extern template semantics 3856Sema::DeclResult 3857Sema::ActOnExplicitInstantiation(Scope *S, 3858 SourceLocation ExternLoc, 3859 SourceLocation TemplateLoc, 3860 unsigned TagSpec, 3861 SourceLocation KWLoc, 3862 const CXXScopeSpec &SS, 3863 TemplateTy TemplateD, 3864 SourceLocation TemplateNameLoc, 3865 SourceLocation LAngleLoc, 3866 ASTTemplateArgsPtr TemplateArgsIn, 3867 SourceLocation RAngleLoc, 3868 AttributeList *Attr) { 3869 // Find the class template we're specializing 3870 TemplateName Name = TemplateD.getAsVal<TemplateName>(); 3871 ClassTemplateDecl *ClassTemplate 3872 = cast<ClassTemplateDecl>(Name.getAsTemplateDecl()); 3873 3874 // Check that the specialization uses the same tag kind as the 3875 // original template. 3876 TagDecl::TagKind Kind; 3877 switch (TagSpec) { 3878 default: assert(0 && "Unknown tag type!"); 3879 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3880 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3881 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3882 } 3883 if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(), 3884 Kind, KWLoc, 3885 *ClassTemplate->getIdentifier())) { 3886 Diag(KWLoc, diag::err_use_with_wrong_tag) 3887 << ClassTemplate 3888 << CodeModificationHint::CreateReplacement(KWLoc, 3889 ClassTemplate->getTemplatedDecl()->getKindName()); 3890 Diag(ClassTemplate->getTemplatedDecl()->getLocation(), 3891 diag::note_previous_use); 3892 Kind = ClassTemplate->getTemplatedDecl()->getTagKind(); 3893 } 3894 3895 // C++0x [temp.explicit]p2: 3896 // There are two forms of explicit instantiation: an explicit instantiation 3897 // definition and an explicit instantiation declaration. An explicit 3898 // instantiation declaration begins with the extern keyword. [...] 3899 TemplateSpecializationKind TSK 3900 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 3901 : TSK_ExplicitInstantiationDeclaration; 3902 3903 // Translate the parser's template argument list in our AST format. 3904 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 3905 translateTemplateArguments(TemplateArgsIn, TemplateArgs); 3906 3907 // Check that the template argument list is well-formed for this 3908 // template. 3909 TemplateArgumentListBuilder Converted(ClassTemplate->getTemplateParameters(), 3910 TemplateArgs.size()); 3911 if (CheckTemplateArgumentList(ClassTemplate, TemplateNameLoc, LAngleLoc, 3912 TemplateArgs.data(), TemplateArgs.size(), 3913 RAngleLoc, false, Converted)) 3914 return true; 3915 3916 assert((Converted.structuredSize() == 3917 ClassTemplate->getTemplateParameters()->size()) && 3918 "Converted template argument list is too short!"); 3919 3920 // Find the class template specialization declaration that 3921 // corresponds to these arguments. 3922 llvm::FoldingSetNodeID ID; 3923 ClassTemplateSpecializationDecl::Profile(ID, 3924 Converted.getFlatArguments(), 3925 Converted.flatSize(), 3926 Context); 3927 void *InsertPos = 0; 3928 ClassTemplateSpecializationDecl *PrevDecl 3929 = ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 3930 3931 // C++0x [temp.explicit]p2: 3932 // [...] An explicit instantiation shall appear in an enclosing 3933 // namespace of its template. [...] 3934 // 3935 // This is C++ DR 275. 3936 CheckExplicitInstantiationScope(*this, ClassTemplate, TemplateNameLoc, 3937 SS.isSet()); 3938 3939 ClassTemplateSpecializationDecl *Specialization = 0; 3940 3941 if (PrevDecl) { 3942 bool SuppressNew = false; 3943 if (CheckSpecializationInstantiationRedecl(TemplateNameLoc, TSK, 3944 PrevDecl, 3945 PrevDecl->getSpecializationKind(), 3946 PrevDecl->getPointOfInstantiation(), 3947 SuppressNew)) 3948 return DeclPtrTy::make(PrevDecl); 3949 3950 if (SuppressNew) 3951 return DeclPtrTy::make(PrevDecl); 3952 3953 if (PrevDecl->getSpecializationKind() == TSK_ImplicitInstantiation || 3954 PrevDecl->getSpecializationKind() == TSK_Undeclared) { 3955 // Since the only prior class template specialization with these 3956 // arguments was referenced but not declared, reuse that 3957 // declaration node as our own, updating its source location to 3958 // reflect our new declaration. 3959 Specialization = PrevDecl; 3960 Specialization->setLocation(TemplateNameLoc); 3961 PrevDecl = 0; 3962 } 3963 } 3964 3965 if (!Specialization) { 3966 // Create a new class template specialization declaration node for 3967 // this explicit specialization. 3968 Specialization 3969 = ClassTemplateSpecializationDecl::Create(Context, 3970 ClassTemplate->getDeclContext(), 3971 TemplateNameLoc, 3972 ClassTemplate, 3973 Converted, PrevDecl); 3974 3975 if (PrevDecl) { 3976 // Remove the previous declaration from the folding set, since we want 3977 // to introduce a new declaration. 3978 ClassTemplate->getSpecializations().RemoveNode(PrevDecl); 3979 ClassTemplate->getSpecializations().FindNodeOrInsertPos(ID, InsertPos); 3980 } 3981 3982 // Insert the new specialization. 3983 ClassTemplate->getSpecializations().InsertNode(Specialization, InsertPos); 3984 } 3985 3986 // Build the fully-sugared type for this explicit instantiation as 3987 // the user wrote in the explicit instantiation itself. This means 3988 // that we'll pretty-print the type retrieved from the 3989 // specialization's declaration the way that the user actually wrote 3990 // the explicit instantiation, rather than formatting the name based 3991 // on the "canonical" representation used to store the template 3992 // arguments in the specialization. 3993 QualType WrittenTy 3994 = Context.getTemplateSpecializationType(Name, 3995 TemplateArgs.data(), 3996 TemplateArgs.size(), 3997 Context.getTypeDeclType(Specialization)); 3998 Specialization->setTypeAsWritten(WrittenTy); 3999 TemplateArgsIn.release(); 4000 4001 // Add the explicit instantiation into its lexical context. However, 4002 // since explicit instantiations are never found by name lookup, we 4003 // just put it into the declaration context directly. 4004 Specialization->setLexicalDeclContext(CurContext); 4005 CurContext->addDecl(Specialization); 4006 4007 // C++ [temp.explicit]p3: 4008 // A definition of a class template or class member template 4009 // shall be in scope at the point of the explicit instantiation of 4010 // the class template or class member template. 4011 // 4012 // This check comes when we actually try to perform the 4013 // instantiation. 4014 ClassTemplateSpecializationDecl *Def 4015 = cast_or_null<ClassTemplateSpecializationDecl>( 4016 Specialization->getDefinition(Context)); 4017 if (!Def) 4018 InstantiateClassTemplateSpecialization(TemplateNameLoc, Specialization, TSK); 4019 4020 // Instantiate the members of this class template specialization. 4021 Def = cast_or_null<ClassTemplateSpecializationDecl>( 4022 Specialization->getDefinition(Context)); 4023 if (Def) 4024 InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK); 4025 4026 return DeclPtrTy::make(Specialization); 4027} 4028 4029// Explicit instantiation of a member class of a class template. 4030Sema::DeclResult 4031Sema::ActOnExplicitInstantiation(Scope *S, 4032 SourceLocation ExternLoc, 4033 SourceLocation TemplateLoc, 4034 unsigned TagSpec, 4035 SourceLocation KWLoc, 4036 const CXXScopeSpec &SS, 4037 IdentifierInfo *Name, 4038 SourceLocation NameLoc, 4039 AttributeList *Attr) { 4040 4041 bool Owned = false; 4042 bool IsDependent = false; 4043 DeclPtrTy TagD = ActOnTag(S, TagSpec, Action::TUK_Reference, 4044 KWLoc, SS, Name, NameLoc, Attr, AS_none, 4045 MultiTemplateParamsArg(*this, 0, 0), 4046 Owned, IsDependent); 4047 assert(!IsDependent && "explicit instantiation of dependent name not yet handled"); 4048 4049 if (!TagD) 4050 return true; 4051 4052 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4053 if (Tag->isEnum()) { 4054 Diag(TemplateLoc, diag::err_explicit_instantiation_enum) 4055 << Context.getTypeDeclType(Tag); 4056 return true; 4057 } 4058 4059 if (Tag->isInvalidDecl()) 4060 return true; 4061 4062 CXXRecordDecl *Record = cast<CXXRecordDecl>(Tag); 4063 CXXRecordDecl *Pattern = Record->getInstantiatedFromMemberClass(); 4064 if (!Pattern) { 4065 Diag(TemplateLoc, diag::err_explicit_instantiation_nontemplate_type) 4066 << Context.getTypeDeclType(Record); 4067 Diag(Record->getLocation(), diag::note_nontemplate_decl_here); 4068 return true; 4069 } 4070 4071 // C++0x [temp.explicit]p2: 4072 // If the explicit instantiation is for a class or member class, the 4073 // elaborated-type-specifier in the declaration shall include a 4074 // simple-template-id. 4075 // 4076 // C++98 has the same restriction, just worded differently. 4077 if (!ScopeSpecifierHasTemplateId(SS)) 4078 Diag(TemplateLoc, diag::err_explicit_instantiation_without_qualified_id) 4079 << Record << SS.getRange(); 4080 4081 // C++0x [temp.explicit]p2: 4082 // There are two forms of explicit instantiation: an explicit instantiation 4083 // definition and an explicit instantiation declaration. An explicit 4084 // instantiation declaration begins with the extern keyword. [...] 4085 TemplateSpecializationKind TSK 4086 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4087 : TSK_ExplicitInstantiationDeclaration; 4088 4089 // C++0x [temp.explicit]p2: 4090 // [...] An explicit instantiation shall appear in an enclosing 4091 // namespace of its template. [...] 4092 // 4093 // This is C++ DR 275. 4094 CheckExplicitInstantiationScope(*this, Record, NameLoc, true); 4095 4096 // Verify that it is okay to explicitly instantiate here. 4097 CXXRecordDecl *PrevDecl 4098 = cast_or_null<CXXRecordDecl>(Record->getPreviousDeclaration()); 4099 if (!PrevDecl && Record->getDefinition(Context)) 4100 PrevDecl = Record; 4101 if (PrevDecl) { 4102 MemberSpecializationInfo *MSInfo = PrevDecl->getMemberSpecializationInfo(); 4103 bool SuppressNew = false; 4104 assert(MSInfo && "No member specialization information?"); 4105 if (CheckSpecializationInstantiationRedecl(TemplateLoc, TSK, 4106 PrevDecl, 4107 MSInfo->getTemplateSpecializationKind(), 4108 MSInfo->getPointOfInstantiation(), 4109 SuppressNew)) 4110 return true; 4111 if (SuppressNew) 4112 return TagD; 4113 } 4114 4115 CXXRecordDecl *RecordDef 4116 = cast_or_null<CXXRecordDecl>(Record->getDefinition(Context)); 4117 if (!RecordDef) { 4118 // C++ [temp.explicit]p3: 4119 // A definition of a member class of a class template shall be in scope 4120 // at the point of an explicit instantiation of the member class. 4121 CXXRecordDecl *Def 4122 = cast_or_null<CXXRecordDecl>(Pattern->getDefinition(Context)); 4123 if (!Def) { 4124 Diag(TemplateLoc, diag::err_explicit_instantiation_undefined_member) 4125 << 0 << Record->getDeclName() << Record->getDeclContext(); 4126 Diag(Pattern->getLocation(), diag::note_forward_declaration) 4127 << Pattern; 4128 return true; 4129 } else { 4130 if (InstantiateClass(NameLoc, Record, Def, 4131 getTemplateInstantiationArgs(Record), 4132 TSK)) 4133 return true; 4134 4135 RecordDef = cast_or_null<CXXRecordDecl>(Record->getDefinition(Context)); 4136 if (!RecordDef) 4137 return true; 4138 } 4139 } 4140 4141 // Instantiate all of the members of the class. 4142 InstantiateClassMembers(NameLoc, RecordDef, 4143 getTemplateInstantiationArgs(Record), TSK); 4144 4145 // FIXME: We don't have any representation for explicit instantiations of 4146 // member classes. Such a representation is not needed for compilation, but it 4147 // should be available for clients that want to see all of the declarations in 4148 // the source code. 4149 return TagD; 4150} 4151 4152Sema::DeclResult Sema::ActOnExplicitInstantiation(Scope *S, 4153 SourceLocation ExternLoc, 4154 SourceLocation TemplateLoc, 4155 Declarator &D) { 4156 // Explicit instantiations always require a name. 4157 DeclarationName Name = GetNameForDeclarator(D); 4158 if (!Name) { 4159 if (!D.isInvalidType()) 4160 Diag(D.getDeclSpec().getSourceRange().getBegin(), 4161 diag::err_explicit_instantiation_requires_name) 4162 << D.getDeclSpec().getSourceRange() 4163 << D.getSourceRange(); 4164 4165 return true; 4166 } 4167 4168 // The scope passed in may not be a decl scope. Zip up the scope tree until 4169 // we find one that is. 4170 while ((S->getFlags() & Scope::DeclScope) == 0 || 4171 (S->getFlags() & Scope::TemplateParamScope) != 0) 4172 S = S->getParent(); 4173 4174 // Determine the type of the declaration. 4175 QualType R = GetTypeForDeclarator(D, S, 0); 4176 if (R.isNull()) 4177 return true; 4178 4179 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 4180 // Cannot explicitly instantiate a typedef. 4181 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_of_typedef) 4182 << Name; 4183 return true; 4184 } 4185 4186 // C++0x [temp.explicit]p1: 4187 // [...] An explicit instantiation of a function template shall not use the 4188 // inline or constexpr specifiers. 4189 // Presumably, this also applies to member functions of class templates as 4190 // well. 4191 if (D.getDeclSpec().isInlineSpecified() && getLangOptions().CPlusPlus0x) 4192 Diag(D.getDeclSpec().getInlineSpecLoc(), 4193 diag::err_explicit_instantiation_inline) 4194 << CodeModificationHint::CreateRemoval( 4195 SourceRange(D.getDeclSpec().getInlineSpecLoc())); 4196 4197 // FIXME: check for constexpr specifier. 4198 4199 // C++0x [temp.explicit]p2: 4200 // There are two forms of explicit instantiation: an explicit instantiation 4201 // definition and an explicit instantiation declaration. An explicit 4202 // instantiation declaration begins with the extern keyword. [...] 4203 TemplateSpecializationKind TSK 4204 = ExternLoc.isInvalid()? TSK_ExplicitInstantiationDefinition 4205 : TSK_ExplicitInstantiationDeclaration; 4206 4207 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName); 4208 LookupParsedName(Previous, S, &D.getCXXScopeSpec()); 4209 4210 if (!R->isFunctionType()) { 4211 // C++ [temp.explicit]p1: 4212 // A [...] static data member of a class template can be explicitly 4213 // instantiated from the member definition associated with its class 4214 // template. 4215 if (Previous.isAmbiguous()) 4216 return true; 4217 4218 VarDecl *Prev = dyn_cast_or_null<VarDecl>( 4219 Previous.getAsSingleDecl(Context)); 4220 if (!Prev || !Prev->isStaticDataMember()) { 4221 // We expect to see a data data member here. 4222 Diag(D.getIdentifierLoc(), diag::err_explicit_instantiation_not_known) 4223 << Name; 4224 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 4225 P != PEnd; ++P) 4226 Diag((*P)->getLocation(), diag::note_explicit_instantiation_here); 4227 return true; 4228 } 4229 4230 if (!Prev->getInstantiatedFromStaticDataMember()) { 4231 // FIXME: Check for explicit specialization? 4232 Diag(D.getIdentifierLoc(), 4233 diag::err_explicit_instantiation_data_member_not_instantiated) 4234 << Prev; 4235 Diag(Prev->getLocation(), diag::note_explicit_instantiation_here); 4236 // FIXME: Can we provide a note showing where this was declared? 4237 return true; 4238 } 4239 4240 // C++0x [temp.explicit]p2: 4241 // If the explicit instantiation is for a member function, a member class 4242 // or a static data member of a class template specialization, the name of 4243 // the class template specialization in the qualified-id for the member 4244 // name shall be a simple-template-id. 4245 // 4246 // C++98 has the same restriction, just worded differently. 4247 if (!ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 4248 Diag(D.getIdentifierLoc(), 4249 diag::err_explicit_instantiation_without_qualified_id) 4250 << Prev << D.getCXXScopeSpec().getRange(); 4251 4252 // Check the scope of this explicit instantiation. 4253 CheckExplicitInstantiationScope(*this, Prev, D.getIdentifierLoc(), true); 4254 4255 // Verify that it is okay to explicitly instantiate here. 4256 MemberSpecializationInfo *MSInfo = Prev->getMemberSpecializationInfo(); 4257 assert(MSInfo && "Missing static data member specialization info?"); 4258 bool SuppressNew = false; 4259 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, Prev, 4260 MSInfo->getTemplateSpecializationKind(), 4261 MSInfo->getPointOfInstantiation(), 4262 SuppressNew)) 4263 return true; 4264 if (SuppressNew) 4265 return DeclPtrTy(); 4266 4267 // Instantiate static data member. 4268 Prev->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 4269 if (TSK == TSK_ExplicitInstantiationDefinition) 4270 InstantiateStaticDataMemberDefinition(D.getIdentifierLoc(), Prev, false, 4271 /*DefinitionRequired=*/true); 4272 4273 // FIXME: Create an ExplicitInstantiation node? 4274 return DeclPtrTy(); 4275 } 4276 4277 // If the declarator is a template-id, translate the parser's template 4278 // argument list into our AST format. 4279 bool HasExplicitTemplateArgs = false; 4280 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 4281 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4282 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4283 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4284 TemplateId->getTemplateArgs(), 4285 TemplateId->NumArgs); 4286 translateTemplateArguments(TemplateArgsPtr, 4287 TemplateArgs); 4288 HasExplicitTemplateArgs = true; 4289 TemplateArgsPtr.release(); 4290 } 4291 4292 // C++ [temp.explicit]p1: 4293 // A [...] function [...] can be explicitly instantiated from its template. 4294 // A member function [...] of a class template can be explicitly 4295 // instantiated from the member definition associated with its class 4296 // template. 4297 llvm::SmallVector<FunctionDecl *, 8> Matches; 4298 for (LookupResult::iterator P = Previous.begin(), PEnd = Previous.end(); 4299 P != PEnd; ++P) { 4300 NamedDecl *Prev = *P; 4301 if (!HasExplicitTemplateArgs) { 4302 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Prev)) { 4303 if (Context.hasSameUnqualifiedType(Method->getType(), R)) { 4304 Matches.clear(); 4305 Matches.push_back(Method); 4306 break; 4307 } 4308 } 4309 } 4310 4311 FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Prev); 4312 if (!FunTmpl) 4313 continue; 4314 4315 TemplateDeductionInfo Info(Context); 4316 FunctionDecl *Specialization = 0; 4317 if (TemplateDeductionResult TDK 4318 = DeduceTemplateArguments(FunTmpl, HasExplicitTemplateArgs, 4319 TemplateArgs.data(), TemplateArgs.size(), 4320 R, Specialization, Info)) { 4321 // FIXME: Keep track of almost-matches? 4322 (void)TDK; 4323 continue; 4324 } 4325 4326 Matches.push_back(Specialization); 4327 } 4328 4329 // Find the most specialized function template specialization. 4330 FunctionDecl *Specialization 4331 = getMostSpecialized(Matches.data(), Matches.size(), TPOC_Other, 4332 D.getIdentifierLoc(), 4333 PartialDiagnostic(diag::err_explicit_instantiation_not_known) << Name, 4334 PartialDiagnostic(diag::err_explicit_instantiation_ambiguous) << Name, 4335 PartialDiagnostic(diag::note_explicit_instantiation_candidate)); 4336 4337 if (!Specialization) 4338 return true; 4339 4340 if (Specialization->getTemplateSpecializationKind() == TSK_Undeclared) { 4341 Diag(D.getIdentifierLoc(), 4342 diag::err_explicit_instantiation_member_function_not_instantiated) 4343 << Specialization 4344 << (Specialization->getTemplateSpecializationKind() == 4345 TSK_ExplicitSpecialization); 4346 Diag(Specialization->getLocation(), diag::note_explicit_instantiation_here); 4347 return true; 4348 } 4349 4350 FunctionDecl *PrevDecl = Specialization->getPreviousDeclaration(); 4351 if (!PrevDecl && Specialization->isThisDeclarationADefinition()) 4352 PrevDecl = Specialization; 4353 4354 if (PrevDecl) { 4355 bool SuppressNew = false; 4356 if (CheckSpecializationInstantiationRedecl(D.getIdentifierLoc(), TSK, 4357 PrevDecl, 4358 PrevDecl->getTemplateSpecializationKind(), 4359 PrevDecl->getPointOfInstantiation(), 4360 SuppressNew)) 4361 return true; 4362 4363 // FIXME: We may still want to build some representation of this 4364 // explicit specialization. 4365 if (SuppressNew) 4366 return DeclPtrTy(); 4367 } 4368 4369 if (TSK == TSK_ExplicitInstantiationDefinition) 4370 InstantiateFunctionDefinition(D.getIdentifierLoc(), Specialization, 4371 false, /*DefinitionRequired=*/true); 4372 4373 Specialization->setTemplateSpecializationKind(TSK, D.getIdentifierLoc()); 4374 4375 // C++0x [temp.explicit]p2: 4376 // If the explicit instantiation is for a member function, a member class 4377 // or a static data member of a class template specialization, the name of 4378 // the class template specialization in the qualified-id for the member 4379 // name shall be a simple-template-id. 4380 // 4381 // C++98 has the same restriction, just worded differently. 4382 FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate(); 4383 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl && 4384 D.getCXXScopeSpec().isSet() && 4385 !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec())) 4386 Diag(D.getIdentifierLoc(), 4387 diag::err_explicit_instantiation_without_qualified_id) 4388 << Specialization << D.getCXXScopeSpec().getRange(); 4389 4390 CheckExplicitInstantiationScope(*this, 4391 FunTmpl? (NamedDecl *)FunTmpl 4392 : Specialization->getInstantiatedFromMemberFunction(), 4393 D.getIdentifierLoc(), 4394 D.getCXXScopeSpec().isSet()); 4395 4396 // FIXME: Create some kind of ExplicitInstantiationDecl here. 4397 return DeclPtrTy(); 4398} 4399 4400Sema::TypeResult 4401Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4402 const CXXScopeSpec &SS, IdentifierInfo *Name, 4403 SourceLocation TagLoc, SourceLocation NameLoc) { 4404 // This has to hold, because SS is expected to be defined. 4405 assert(Name && "Expected a name in a dependent tag"); 4406 4407 NestedNameSpecifier *NNS 4408 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 4409 if (!NNS) 4410 return true; 4411 4412 QualType T = CheckTypenameType(NNS, *Name, SourceRange(TagLoc, NameLoc)); 4413 if (T.isNull()) 4414 return true; 4415 4416 TagDecl::TagKind TagKind = TagDecl::getTagKindForTypeSpec(TagSpec); 4417 QualType ElabType = Context.getElaboratedType(T, TagKind); 4418 4419 return ElabType.getAsOpaquePtr(); 4420} 4421 4422Sema::TypeResult 4423Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS, 4424 const IdentifierInfo &II, SourceLocation IdLoc) { 4425 NestedNameSpecifier *NNS 4426 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 4427 if (!NNS) 4428 return true; 4429 4430 QualType T = CheckTypenameType(NNS, II, SourceRange(TypenameLoc, IdLoc)); 4431 if (T.isNull()) 4432 return true; 4433 return T.getAsOpaquePtr(); 4434} 4435 4436Sema::TypeResult 4437Sema::ActOnTypenameType(SourceLocation TypenameLoc, const CXXScopeSpec &SS, 4438 SourceLocation TemplateLoc, TypeTy *Ty) { 4439 QualType T = GetTypeFromParser(Ty); 4440 NestedNameSpecifier *NNS 4441 = static_cast<NestedNameSpecifier *>(SS.getScopeRep()); 4442 const TemplateSpecializationType *TemplateId 4443 = T->getAs<TemplateSpecializationType>(); 4444 assert(TemplateId && "Expected a template specialization type"); 4445 4446 if (computeDeclContext(SS, false)) { 4447 // If we can compute a declaration context, then the "typename" 4448 // keyword was superfluous. Just build a QualifiedNameType to keep 4449 // track of the nested-name-specifier. 4450 4451 // FIXME: Note that the QualifiedNameType had the "typename" keyword! 4452 return Context.getQualifiedNameType(NNS, T).getAsOpaquePtr(); 4453 } 4454 4455 return Context.getTypenameType(NNS, TemplateId).getAsOpaquePtr(); 4456} 4457 4458/// \brief Build the type that describes a C++ typename specifier, 4459/// e.g., "typename T::type". 4460QualType 4461Sema::CheckTypenameType(NestedNameSpecifier *NNS, const IdentifierInfo &II, 4462 SourceRange Range) { 4463 CXXRecordDecl *CurrentInstantiation = 0; 4464 if (NNS->isDependent()) { 4465 CurrentInstantiation = getCurrentInstantiationOf(NNS); 4466 4467 // If the nested-name-specifier does not refer to the current 4468 // instantiation, then build a typename type. 4469 if (!CurrentInstantiation) 4470 return Context.getTypenameType(NNS, &II); 4471 4472 // The nested-name-specifier refers to the current instantiation, so the 4473 // "typename" keyword itself is superfluous. In C++03, the program is 4474 // actually ill-formed. However, DR 382 (in C++0x CD1) allows such 4475 // extraneous "typename" keywords, and we retroactively apply this DR to 4476 // C++03 code. 4477 } 4478 4479 DeclContext *Ctx = 0; 4480 4481 if (CurrentInstantiation) 4482 Ctx = CurrentInstantiation; 4483 else { 4484 CXXScopeSpec SS; 4485 SS.setScopeRep(NNS); 4486 SS.setRange(Range); 4487 if (RequireCompleteDeclContext(SS)) 4488 return QualType(); 4489 4490 Ctx = computeDeclContext(SS); 4491 } 4492 assert(Ctx && "No declaration context?"); 4493 4494 DeclarationName Name(&II); 4495 LookupResult Result(*this, Name, Range.getEnd(), LookupOrdinaryName); 4496 LookupQualifiedName(Result, Ctx); 4497 unsigned DiagID = 0; 4498 Decl *Referenced = 0; 4499 switch (Result.getResultKind()) { 4500 case LookupResult::NotFound: 4501 DiagID = diag::err_typename_nested_not_found; 4502 break; 4503 4504 case LookupResult::Found: 4505 if (TypeDecl *Type = dyn_cast<TypeDecl>(Result.getFoundDecl())) { 4506 // We found a type. Build a QualifiedNameType, since the 4507 // typename-specifier was just sugar. FIXME: Tell 4508 // QualifiedNameType that it has a "typename" prefix. 4509 return Context.getQualifiedNameType(NNS, Context.getTypeDeclType(Type)); 4510 } 4511 4512 DiagID = diag::err_typename_nested_not_type; 4513 Referenced = Result.getFoundDecl(); 4514 break; 4515 4516 case LookupResult::FoundUnresolvedValue: 4517 llvm::llvm_unreachable("unresolved using decl in non-dependent context"); 4518 return QualType(); 4519 4520 case LookupResult::FoundOverloaded: 4521 DiagID = diag::err_typename_nested_not_type; 4522 Referenced = *Result.begin(); 4523 break; 4524 4525 case LookupResult::Ambiguous: 4526 return QualType(); 4527 } 4528 4529 // If we get here, it's because name lookup did not find a 4530 // type. Emit an appropriate diagnostic and return an error. 4531 Diag(Range.getEnd(), DiagID) << Range << Name << Ctx; 4532 if (Referenced) 4533 Diag(Referenced->getLocation(), diag::note_typename_refers_here) 4534 << Name; 4535 return QualType(); 4536} 4537 4538namespace { 4539 // See Sema::RebuildTypeInCurrentInstantiation 4540 class VISIBILITY_HIDDEN CurrentInstantiationRebuilder 4541 : public TreeTransform<CurrentInstantiationRebuilder> { 4542 SourceLocation Loc; 4543 DeclarationName Entity; 4544 4545 public: 4546 CurrentInstantiationRebuilder(Sema &SemaRef, 4547 SourceLocation Loc, 4548 DeclarationName Entity) 4549 : TreeTransform<CurrentInstantiationRebuilder>(SemaRef), 4550 Loc(Loc), Entity(Entity) { } 4551 4552 /// \brief Determine whether the given type \p T has already been 4553 /// transformed. 4554 /// 4555 /// For the purposes of type reconstruction, a type has already been 4556 /// transformed if it is NULL or if it is not dependent. 4557 bool AlreadyTransformed(QualType T) { 4558 return T.isNull() || !T->isDependentType(); 4559 } 4560 4561 /// \brief Returns the location of the entity whose type is being 4562 /// rebuilt. 4563 SourceLocation getBaseLocation() { return Loc; } 4564 4565 /// \brief Returns the name of the entity whose type is being rebuilt. 4566 DeclarationName getBaseEntity() { return Entity; } 4567 4568 /// \brief Sets the "base" location and entity when that 4569 /// information is known based on another transformation. 4570 void setBase(SourceLocation Loc, DeclarationName Entity) { 4571 this->Loc = Loc; 4572 this->Entity = Entity; 4573 } 4574 4575 /// \brief Transforms an expression by returning the expression itself 4576 /// (an identity function). 4577 /// 4578 /// FIXME: This is completely unsafe; we will need to actually clone the 4579 /// expressions. 4580 Sema::OwningExprResult TransformExpr(Expr *E) { 4581 return getSema().Owned(E); 4582 } 4583 4584 /// \brief Transforms a typename type by determining whether the type now 4585 /// refers to a member of the current instantiation, and then 4586 /// type-checking and building a QualifiedNameType (when possible). 4587 QualType TransformTypenameType(TypeLocBuilder &TLB, TypenameTypeLoc TL); 4588 }; 4589} 4590 4591QualType 4592CurrentInstantiationRebuilder::TransformTypenameType(TypeLocBuilder &TLB, 4593 TypenameTypeLoc TL) { 4594 TypenameType *T = TL.getTypePtr(); 4595 4596 NestedNameSpecifier *NNS 4597 = TransformNestedNameSpecifier(T->getQualifier(), 4598 /*FIXME:*/SourceRange(getBaseLocation())); 4599 if (!NNS) 4600 return QualType(); 4601 4602 // If the nested-name-specifier did not change, and we cannot compute the 4603 // context corresponding to the nested-name-specifier, then this 4604 // typename type will not change; exit early. 4605 CXXScopeSpec SS; 4606 SS.setRange(SourceRange(getBaseLocation())); 4607 SS.setScopeRep(NNS); 4608 4609 QualType Result; 4610 if (NNS == T->getQualifier() && getSema().computeDeclContext(SS) == 0) 4611 Result = QualType(T, 0); 4612 4613 // Rebuild the typename type, which will probably turn into a 4614 // QualifiedNameType. 4615 else if (const TemplateSpecializationType *TemplateId = T->getTemplateId()) { 4616 QualType NewTemplateId 4617 = TransformType(QualType(TemplateId, 0)); 4618 if (NewTemplateId.isNull()) 4619 return QualType(); 4620 4621 if (NNS == T->getQualifier() && 4622 NewTemplateId == QualType(TemplateId, 0)) 4623 Result = QualType(T, 0); 4624 else 4625 Result = getDerived().RebuildTypenameType(NNS, NewTemplateId); 4626 } else 4627 Result = getDerived().RebuildTypenameType(NNS, T->getIdentifier(), 4628 SourceRange(TL.getNameLoc())); 4629 4630 TypenameTypeLoc NewTL = TLB.push<TypenameTypeLoc>(Result); 4631 NewTL.setNameLoc(TL.getNameLoc()); 4632 return Result; 4633} 4634 4635/// \brief Rebuilds a type within the context of the current instantiation. 4636/// 4637/// The type \p T is part of the type of an out-of-line member definition of 4638/// a class template (or class template partial specialization) that was parsed 4639/// and constructed before we entered the scope of the class template (or 4640/// partial specialization thereof). This routine will rebuild that type now 4641/// that we have entered the declarator's scope, which may produce different 4642/// canonical types, e.g., 4643/// 4644/// \code 4645/// template<typename T> 4646/// struct X { 4647/// typedef T* pointer; 4648/// pointer data(); 4649/// }; 4650/// 4651/// template<typename T> 4652/// typename X<T>::pointer X<T>::data() { ... } 4653/// \endcode 4654/// 4655/// Here, the type "typename X<T>::pointer" will be created as a TypenameType, 4656/// since we do not know that we can look into X<T> when we parsed the type. 4657/// This function will rebuild the type, performing the lookup of "pointer" 4658/// in X<T> and returning a QualifiedNameType whose canonical type is the same 4659/// as the canonical type of T*, allowing the return types of the out-of-line 4660/// definition and the declaration to match. 4661QualType Sema::RebuildTypeInCurrentInstantiation(QualType T, SourceLocation Loc, 4662 DeclarationName Name) { 4663 if (T.isNull() || !T->isDependentType()) 4664 return T; 4665 4666 CurrentInstantiationRebuilder Rebuilder(*this, Loc, Name); 4667 return Rebuilder.TransformType(T); 4668} 4669 4670/// \brief Produces a formatted string that describes the binding of 4671/// template parameters to template arguments. 4672std::string 4673Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 4674 const TemplateArgumentList &Args) { 4675 // FIXME: For variadic templates, we'll need to get the structured list. 4676 return getTemplateArgumentBindingsText(Params, Args.getFlatArgumentList(), 4677 Args.flat_size()); 4678} 4679 4680std::string 4681Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params, 4682 const TemplateArgument *Args, 4683 unsigned NumArgs) { 4684 std::string Result; 4685 4686 if (!Params || Params->size() == 0 || NumArgs == 0) 4687 return Result; 4688 4689 for (unsigned I = 0, N = Params->size(); I != N; ++I) { 4690 if (I >= NumArgs) 4691 break; 4692 4693 if (I == 0) 4694 Result += "[with "; 4695 else 4696 Result += ", "; 4697 4698 if (const IdentifierInfo *Id = Params->getParam(I)->getIdentifier()) { 4699 Result += Id->getName(); 4700 } else { 4701 Result += '$'; 4702 Result += llvm::utostr(I); 4703 } 4704 4705 Result += " = "; 4706 4707 switch (Args[I].getKind()) { 4708 case TemplateArgument::Null: 4709 Result += "<no value>"; 4710 break; 4711 4712 case TemplateArgument::Type: { 4713 std::string TypeStr; 4714 Args[I].getAsType().getAsStringInternal(TypeStr, 4715 Context.PrintingPolicy); 4716 Result += TypeStr; 4717 break; 4718 } 4719 4720 case TemplateArgument::Declaration: { 4721 bool Unnamed = true; 4722 if (NamedDecl *ND = dyn_cast_or_null<NamedDecl>(Args[I].getAsDecl())) { 4723 if (ND->getDeclName()) { 4724 Unnamed = false; 4725 Result += ND->getNameAsString(); 4726 } 4727 } 4728 4729 if (Unnamed) { 4730 Result += "<anonymous>"; 4731 } 4732 break; 4733 } 4734 4735 case TemplateArgument::Template: { 4736 std::string Str; 4737 llvm::raw_string_ostream OS(Str); 4738 Args[I].getAsTemplate().print(OS, Context.PrintingPolicy); 4739 Result += OS.str(); 4740 break; 4741 } 4742 4743 case TemplateArgument::Integral: { 4744 Result += Args[I].getAsIntegral()->toString(10); 4745 break; 4746 } 4747 4748 case TemplateArgument::Expression: { 4749 assert(false && "No expressions in deduced template arguments!"); 4750 Result += "<expression>"; 4751 break; 4752 } 4753 4754 case TemplateArgument::Pack: 4755 // FIXME: Format template argument packs 4756 Result += "<template argument pack>"; 4757 break; 4758 } 4759 } 4760 4761 Result += ']'; 4762 return Result; 4763} 4764