SemaDecl.cpp revision 6943e9befee204becfae55de1298b3d5fee87934
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 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// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Initialization.h" 16#include "clang/Sema/Lookup.h" 17#include "clang/Sema/CXXFieldCollector.h" 18#include "clang/Sema/Scope.h" 19#include "clang/Sema/ScopeInfo.h" 20#include "TypeLocBuilder.h" 21#include "clang/AST/APValue.h" 22#include "clang/AST/ASTConsumer.h" 23#include "clang/AST/ASTContext.h" 24#include "clang/AST/CXXInheritance.h" 25#include "clang/AST/DeclCXX.h" 26#include "clang/AST/DeclObjC.h" 27#include "clang/AST/DeclTemplate.h" 28#include "clang/AST/EvaluatedExprVisitor.h" 29#include "clang/AST/ExprCXX.h" 30#include "clang/AST/StmtCXX.h" 31#include "clang/AST/CharUnits.h" 32#include "clang/Sema/DeclSpec.h" 33#include "clang/Sema/ParsedTemplate.h" 34#include "clang/Parse/ParseDiagnostic.h" 35#include "clang/Basic/PartialDiagnostic.h" 36#include "clang/Basic/SourceManager.h" 37#include "clang/Basic/TargetInfo.h" 38// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 39#include "clang/Lex/Preprocessor.h" 40#include "clang/Lex/HeaderSearch.h" 41#include "llvm/ADT/Triple.h" 42#include <algorithm> 43#include <cstring> 44#include <functional> 45using namespace clang; 46using namespace sema; 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(Decl *Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr)); 50} 51 52/// \brief If the identifier refers to a type name within this scope, 53/// return the declaration of that type. 54/// 55/// This routine performs ordinary name lookup of the identifier II 56/// within the given scope, with optional C++ scope specifier SS, to 57/// determine whether the name refers to a type. If so, returns an 58/// opaque pointer (actually a QualType) corresponding to that 59/// type. Otherwise, returns NULL. 60/// 61/// If name lookup results in an ambiguity, this routine will complain 62/// and then return NULL. 63ParsedType Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, bool HasTrailingDot, 66 ParsedType ObjectTypePtr, 67 bool WantNontrivialTypeSourceInfo) { 68 // Determine where we will perform name lookup. 69 DeclContext *LookupCtx = 0; 70 if (ObjectTypePtr) { 71 QualType ObjectType = ObjectTypePtr.get(); 72 if (ObjectType->isRecordType()) 73 LookupCtx = computeDeclContext(ObjectType); 74 } else if (SS && SS->isNotEmpty()) { 75 LookupCtx = computeDeclContext(*SS, false); 76 77 if (!LookupCtx) { 78 if (isDependentScopeSpecifier(*SS)) { 79 // C++ [temp.res]p3: 80 // A qualified-id that refers to a type and in which the 81 // nested-name-specifier depends on a template-parameter (14.6.2) 82 // shall be prefixed by the keyword typename to indicate that the 83 // qualified-id denotes a type, forming an 84 // elaborated-type-specifier (7.1.5.3). 85 // 86 // We therefore do not perform any name lookup if the result would 87 // refer to a member of an unknown specialization. 88 if (!isClassName) 89 return ParsedType(); 90 91 // We know from the grammar that this name refers to a type, 92 // so build a dependent node to describe the type. 93 if (WantNontrivialTypeSourceInfo) 94 return ActOnTypenameType(S, SourceLocation(), *SS, II, NameLoc).get(); 95 96 NestedNameSpecifierLoc QualifierLoc = SS->getWithLocInContext(Context); 97 QualType T = 98 CheckTypenameType(ETK_None, SourceLocation(), QualifierLoc, 99 II, NameLoc); 100 101 return ParsedType::make(T); 102 } 103 104 return ParsedType(); 105 } 106 107 if (!LookupCtx->isDependentContext() && 108 RequireCompleteDeclContext(*SS, LookupCtx)) 109 return ParsedType(); 110 } 111 112 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 113 // lookup for class-names. 114 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 115 LookupOrdinaryName; 116 LookupResult Result(*this, &II, NameLoc, Kind); 117 if (LookupCtx) { 118 // Perform "qualified" name lookup into the declaration context we 119 // computed, which is either the type of the base of a member access 120 // expression or the declaration context associated with a prior 121 // nested-name-specifier. 122 LookupQualifiedName(Result, LookupCtx); 123 124 if (ObjectTypePtr && Result.empty()) { 125 // C++ [basic.lookup.classref]p3: 126 // If the unqualified-id is ~type-name, the type-name is looked up 127 // in the context of the entire postfix-expression. If the type T of 128 // the object expression is of a class type C, the type-name is also 129 // looked up in the scope of class C. At least one of the lookups shall 130 // find a name that refers to (possibly cv-qualified) T. 131 LookupName(Result, S); 132 } 133 } else { 134 // Perform unqualified name lookup. 135 LookupName(Result, S); 136 } 137 138 NamedDecl *IIDecl = 0; 139 switch (Result.getResultKind()) { 140 case LookupResult::NotFound: 141 case LookupResult::NotFoundInCurrentInstantiation: 142 case LookupResult::FoundOverloaded: 143 case LookupResult::FoundUnresolvedValue: 144 Result.suppressDiagnostics(); 145 return ParsedType(); 146 147 case LookupResult::Ambiguous: 148 // Recover from type-hiding ambiguities by hiding the type. We'll 149 // do the lookup again when looking for an object, and we can 150 // diagnose the error then. If we don't do this, then the error 151 // about hiding the type will be immediately followed by an error 152 // that only makes sense if the identifier was treated like a type. 153 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 154 Result.suppressDiagnostics(); 155 return ParsedType(); 156 } 157 158 // Look to see if we have a type anywhere in the list of results. 159 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 160 Res != ResEnd; ++Res) { 161 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 162 if (!IIDecl || 163 (*Res)->getLocation().getRawEncoding() < 164 IIDecl->getLocation().getRawEncoding()) 165 IIDecl = *Res; 166 } 167 } 168 169 if (!IIDecl) { 170 // None of the entities we found is a type, so there is no way 171 // to even assume that the result is a type. In this case, don't 172 // complain about the ambiguity. The parser will either try to 173 // perform this lookup again (e.g., as an object name), which 174 // will produce the ambiguity, or will complain that it expected 175 // a type name. 176 Result.suppressDiagnostics(); 177 return ParsedType(); 178 } 179 180 // We found a type within the ambiguous lookup; diagnose the 181 // ambiguity and then return that type. This might be the right 182 // answer, or it might not be, but it suppresses any attempt to 183 // perform the name lookup again. 184 break; 185 186 case LookupResult::Found: 187 IIDecl = Result.getFoundDecl(); 188 break; 189 } 190 191 assert(IIDecl && "Didn't find decl"); 192 193 QualType T; 194 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 195 DiagnoseUseOfDecl(IIDecl, NameLoc); 196 197 if (T.isNull()) 198 T = Context.getTypeDeclType(TD); 199 200 if (SS && SS->isNotEmpty()) { 201 if (WantNontrivialTypeSourceInfo) { 202 // Construct a type with type-source information. 203 TypeLocBuilder Builder; 204 Builder.pushTypeSpec(T).setNameLoc(NameLoc); 205 206 T = getElaboratedType(ETK_None, *SS, T); 207 ElaboratedTypeLoc ElabTL = Builder.push<ElaboratedTypeLoc>(T); 208 ElabTL.setKeywordLoc(SourceLocation()); 209 ElabTL.setQualifierLoc(SS->getWithLocInContext(Context)); 210 return CreateParsedType(T, Builder.getTypeSourceInfo(Context, T)); 211 } else { 212 T = getElaboratedType(ETK_None, *SS, T); 213 } 214 } 215 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 216 (void)DiagnoseUseOfDecl(IDecl, NameLoc); 217 if (!HasTrailingDot) 218 T = Context.getObjCInterfaceType(IDecl); 219 } 220 221 if (T.isNull()) { 222 // If it's not plausibly a type, suppress diagnostics. 223 Result.suppressDiagnostics(); 224 return ParsedType(); 225 } 226 return ParsedType::make(T); 227} 228 229/// isTagName() - This method is called *for error recovery purposes only* 230/// to determine if the specified name is a valid tag name ("struct foo"). If 231/// so, this returns the TST for the tag corresponding to it (TST_enum, 232/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 233/// where the user forgot to specify the tag. 234DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 235 // Do a tag name lookup in this scope. 236 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 237 LookupName(R, S, false); 238 R.suppressDiagnostics(); 239 if (R.getResultKind() == LookupResult::Found) 240 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 241 switch (TD->getTagKind()) { 242 default: return DeclSpec::TST_unspecified; 243 case TTK_Struct: return DeclSpec::TST_struct; 244 case TTK_Union: return DeclSpec::TST_union; 245 case TTK_Class: return DeclSpec::TST_class; 246 case TTK_Enum: return DeclSpec::TST_enum; 247 } 248 } 249 250 return DeclSpec::TST_unspecified; 251} 252 253/// isMicrosoftMissingTypename - In Microsoft mode, within class scope, 254/// if a CXXScopeSpec's type is equal to the type of one of the base classes 255/// then downgrade the missing typename error to a warning. 256/// This is needed for MSVC compatibility; Example: 257/// @code 258/// template<class T> class A { 259/// public: 260/// typedef int TYPE; 261/// }; 262/// template<class T> class B : public A<T> { 263/// public: 264/// A<T>::TYPE a; // no typename required because A<T> is a base class. 265/// }; 266/// @endcode 267bool Sema::isMicrosoftMissingTypename(const CXXScopeSpec *SS) { 268 if (CurContext->isRecord()) { 269 const Type* Ty = SS->getScopeRep()->getAsType(); 270 271 CXXRecordDecl *RD = cast<CXXRecordDecl>(CurContext); 272 for (CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin(), 273 BaseEnd = RD->bases_end(); Base != BaseEnd; ++Base) 274 if (Context.hasSameUnqualifiedType(QualType(Ty, 1), Base->getType())) 275 return true; 276 } 277 return false; 278} 279 280bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 281 SourceLocation IILoc, 282 Scope *S, 283 CXXScopeSpec *SS, 284 ParsedType &SuggestedType) { 285 // We don't have anything to suggest (yet). 286 SuggestedType = ParsedType(); 287 288 // There may have been a typo in the name of the type. Look up typo 289 // results, in case we have something that we can suggest. 290 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 291 NotForRedeclaration); 292 293 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 294 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 295 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 296 !Result->isInvalidDecl()) { 297 // We found a similarly-named type or interface; suggest that. 298 if (!SS || !SS->isSet()) 299 Diag(IILoc, diag::err_unknown_typename_suggest) 300 << &II << Lookup.getLookupName() 301 << FixItHint::CreateReplacement(SourceRange(IILoc), 302 Result->getNameAsString()); 303 else if (DeclContext *DC = computeDeclContext(*SS, false)) 304 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 305 << &II << DC << Lookup.getLookupName() << SS->getRange() 306 << FixItHint::CreateReplacement(SourceRange(IILoc), 307 Result->getNameAsString()); 308 else 309 llvm_unreachable("could not have corrected a typo here"); 310 311 Diag(Result->getLocation(), diag::note_previous_decl) 312 << Result->getDeclName(); 313 314 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS, 315 false, false, ParsedType(), 316 /*NonTrivialTypeSourceInfo=*/true); 317 return true; 318 } 319 } else if (Lookup.empty()) { 320 // We corrected to a keyword. 321 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 322 Diag(IILoc, diag::err_unknown_typename_suggest) 323 << &II << Corrected; 324 return true; 325 } 326 } 327 328 if (getLangOptions().CPlusPlus) { 329 // See if II is a class template that the user forgot to pass arguments to. 330 UnqualifiedId Name; 331 Name.setIdentifier(&II, IILoc); 332 CXXScopeSpec EmptySS; 333 TemplateTy TemplateResult; 334 bool MemberOfUnknownSpecialization; 335 if (isTemplateName(S, SS ? *SS : EmptySS, /*hasTemplateKeyword=*/false, 336 Name, ParsedType(), true, TemplateResult, 337 MemberOfUnknownSpecialization) == TNK_Type_template) { 338 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 339 Diag(IILoc, diag::err_template_missing_args) << TplName; 340 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 341 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 342 << TplDecl->getTemplateParameters()->getSourceRange(); 343 } 344 return true; 345 } 346 } 347 348 // FIXME: Should we move the logic that tries to recover from a missing tag 349 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 350 351 if (!SS || (!SS->isSet() && !SS->isInvalid())) 352 Diag(IILoc, diag::err_unknown_typename) << &II; 353 else if (DeclContext *DC = computeDeclContext(*SS, false)) 354 Diag(IILoc, diag::err_typename_nested_not_found) 355 << &II << DC << SS->getRange(); 356 else if (isDependentScopeSpecifier(*SS)) { 357 unsigned DiagID = diag::err_typename_missing; 358 if (getLangOptions().Microsoft && isMicrosoftMissingTypename(SS)) 359 DiagID = diag::war_typename_missing; 360 361 Diag(SS->getRange().getBegin(), DiagID) 362 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 363 << SourceRange(SS->getRange().getBegin(), IILoc) 364 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 365 SuggestedType = ActOnTypenameType(S, SourceLocation(), *SS, II, IILoc).get(); 366 } else { 367 assert(SS && SS->isInvalid() && 368 "Invalid scope specifier has already been diagnosed"); 369 } 370 371 return true; 372} 373 374// Determines the context to return to after temporarily entering a 375// context. This depends in an unnecessarily complicated way on the 376// exact ordering of callbacks from the parser. 377DeclContext *Sema::getContainingDC(DeclContext *DC) { 378 379 // Functions defined inline within classes aren't parsed until we've 380 // finished parsing the top-level class, so the top-level class is 381 // the context we'll need to return to. 382 if (isa<FunctionDecl>(DC)) { 383 DC = DC->getLexicalParent(); 384 385 // A function not defined within a class will always return to its 386 // lexical context. 387 if (!isa<CXXRecordDecl>(DC)) 388 return DC; 389 390 // A C++ inline method/friend is parsed *after* the topmost class 391 // it was declared in is fully parsed ("complete"); the topmost 392 // class is the context we need to return to. 393 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 394 DC = RD; 395 396 // Return the declaration context of the topmost class the inline method is 397 // declared in. 398 return DC; 399 } 400 401 // ObjCMethodDecls are parsed (for some reason) outside the context 402 // of the class. 403 if (isa<ObjCMethodDecl>(DC)) 404 return DC->getLexicalParent()->getLexicalParent(); 405 406 return DC->getLexicalParent(); 407} 408 409void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 410 assert(getContainingDC(DC) == CurContext && 411 "The next DeclContext should be lexically contained in the current one."); 412 CurContext = DC; 413 S->setEntity(DC); 414} 415 416void Sema::PopDeclContext() { 417 assert(CurContext && "DeclContext imbalance!"); 418 419 CurContext = getContainingDC(CurContext); 420 assert(CurContext && "Popped translation unit!"); 421} 422 423/// EnterDeclaratorContext - Used when we must lookup names in the context 424/// of a declarator's nested name specifier. 425/// 426void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 427 // C++0x [basic.lookup.unqual]p13: 428 // A name used in the definition of a static data member of class 429 // X (after the qualified-id of the static member) is looked up as 430 // if the name was used in a member function of X. 431 // C++0x [basic.lookup.unqual]p14: 432 // If a variable member of a namespace is defined outside of the 433 // scope of its namespace then any name used in the definition of 434 // the variable member (after the declarator-id) is looked up as 435 // if the definition of the variable member occurred in its 436 // namespace. 437 // Both of these imply that we should push a scope whose context 438 // is the semantic context of the declaration. We can't use 439 // PushDeclContext here because that context is not necessarily 440 // lexically contained in the current context. Fortunately, 441 // the containing scope should have the appropriate information. 442 443 assert(!S->getEntity() && "scope already has entity"); 444 445#ifndef NDEBUG 446 Scope *Ancestor = S->getParent(); 447 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 448 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 449#endif 450 451 CurContext = DC; 452 S->setEntity(DC); 453} 454 455void Sema::ExitDeclaratorContext(Scope *S) { 456 assert(S->getEntity() == CurContext && "Context imbalance!"); 457 458 // Switch back to the lexical context. The safety of this is 459 // enforced by an assert in EnterDeclaratorContext. 460 Scope *Ancestor = S->getParent(); 461 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 462 CurContext = (DeclContext*) Ancestor->getEntity(); 463 464 // We don't need to do anything with the scope, which is going to 465 // disappear. 466} 467 468/// \brief Determine whether we allow overloading of the function 469/// PrevDecl with another declaration. 470/// 471/// This routine determines whether overloading is possible, not 472/// whether some new function is actually an overload. It will return 473/// true in C++ (where we can always provide overloads) or, as an 474/// extension, in C when the previous function is already an 475/// overloaded function declaration or has the "overloadable" 476/// attribute. 477static bool AllowOverloadingOfFunction(LookupResult &Previous, 478 ASTContext &Context) { 479 if (Context.getLangOptions().CPlusPlus) 480 return true; 481 482 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 483 return true; 484 485 return (Previous.getResultKind() == LookupResult::Found 486 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 487} 488 489/// Add this decl to the scope shadowed decl chains. 490void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 491 // Move up the scope chain until we find the nearest enclosing 492 // non-transparent context. The declaration will be introduced into this 493 // scope. 494 while (S->getEntity() && 495 ((DeclContext *)S->getEntity())->isTransparentContext()) 496 S = S->getParent(); 497 498 // Add scoped declarations into their context, so that they can be 499 // found later. Declarations without a context won't be inserted 500 // into any context. 501 if (AddToContext) 502 CurContext->addDecl(D); 503 504 // Out-of-line definitions shouldn't be pushed into scope in C++. 505 // Out-of-line variable and function definitions shouldn't even in C. 506 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 507 D->isOutOfLine()) 508 return; 509 510 // Template instantiations should also not be pushed into scope. 511 if (isa<FunctionDecl>(D) && 512 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 513 return; 514 515 // If this replaces anything in the current scope, 516 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 517 IEnd = IdResolver.end(); 518 for (; I != IEnd; ++I) { 519 if (S->isDeclScope(*I) && D->declarationReplaces(*I)) { 520 S->RemoveDecl(*I); 521 IdResolver.RemoveDecl(*I); 522 523 // Should only need to replace one decl. 524 break; 525 } 526 } 527 528 S->AddDecl(D); 529 530 if (isa<LabelDecl>(D) && !cast<LabelDecl>(D)->isGnuLocal()) { 531 // Implicitly-generated labels may end up getting generated in an order that 532 // isn't strictly lexical, which breaks name lookup. Be careful to insert 533 // the label at the appropriate place in the identifier chain. 534 for (I = IdResolver.begin(D->getDeclName()); I != IEnd; ++I) { 535 DeclContext *IDC = (*I)->getLexicalDeclContext()->getRedeclContext(); 536 if (IDC == CurContext) { 537 if (!S->isDeclScope(*I)) 538 continue; 539 } else if (IDC->Encloses(CurContext)) 540 break; 541 } 542 543 IdResolver.InsertDeclAfter(I, D); 544 } else { 545 IdResolver.AddDecl(D); 546 } 547} 548 549bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S, 550 bool ExplicitInstantiationOrSpecialization) { 551 return IdResolver.isDeclInScope(D, Ctx, Context, S, 552 ExplicitInstantiationOrSpecialization); 553} 554 555Scope *Sema::getScopeForDeclContext(Scope *S, DeclContext *DC) { 556 DeclContext *TargetDC = DC->getPrimaryContext(); 557 do { 558 if (DeclContext *ScopeDC = (DeclContext*) S->getEntity()) 559 if (ScopeDC->getPrimaryContext() == TargetDC) 560 return S; 561 } while ((S = S->getParent())); 562 563 return 0; 564} 565 566static bool isOutOfScopePreviousDeclaration(NamedDecl *, 567 DeclContext*, 568 ASTContext&); 569 570/// Filters out lookup results that don't fall within the given scope 571/// as determined by isDeclInScope. 572static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 573 DeclContext *Ctx, Scope *S, 574 bool ConsiderLinkage, 575 bool ExplicitInstantiationOrSpecialization) { 576 LookupResult::Filter F = R.makeFilter(); 577 while (F.hasNext()) { 578 NamedDecl *D = F.next(); 579 580 if (SemaRef.isDeclInScope(D, Ctx, S, ExplicitInstantiationOrSpecialization)) 581 continue; 582 583 if (ConsiderLinkage && 584 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 585 continue; 586 587 F.erase(); 588 } 589 590 F.done(); 591} 592 593static bool isUsingDecl(NamedDecl *D) { 594 return isa<UsingShadowDecl>(D) || 595 isa<UnresolvedUsingTypenameDecl>(D) || 596 isa<UnresolvedUsingValueDecl>(D); 597} 598 599/// Removes using shadow declarations from the lookup results. 600static void RemoveUsingDecls(LookupResult &R) { 601 LookupResult::Filter F = R.makeFilter(); 602 while (F.hasNext()) 603 if (isUsingDecl(F.next())) 604 F.erase(); 605 606 F.done(); 607} 608 609/// \brief Check for this common pattern: 610/// @code 611/// class S { 612/// S(const S&); // DO NOT IMPLEMENT 613/// void operator=(const S&); // DO NOT IMPLEMENT 614/// }; 615/// @endcode 616static bool IsDisallowedCopyOrAssign(const CXXMethodDecl *D) { 617 // FIXME: Should check for private access too but access is set after we get 618 // the decl here. 619 if (D->isThisDeclarationADefinition()) 620 return false; 621 622 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D)) 623 return CD->isCopyConstructor(); 624 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) 625 return Method->isCopyAssignmentOperator(); 626 return false; 627} 628 629bool Sema::ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const { 630 assert(D); 631 632 if (D->isInvalidDecl() || D->isUsed() || D->hasAttr<UnusedAttr>()) 633 return false; 634 635 // Ignore class templates. 636 if (D->getDeclContext()->isDependentContext() || 637 D->getLexicalDeclContext()->isDependentContext()) 638 return false; 639 640 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 641 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 642 return false; 643 644 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 645 if (MD->isVirtual() || IsDisallowedCopyOrAssign(MD)) 646 return false; 647 } else { 648 // 'static inline' functions are used in headers; don't warn. 649 if (FD->getStorageClass() == SC_Static && 650 FD->isInlineSpecified()) 651 return false; 652 } 653 654 if (FD->isThisDeclarationADefinition() && 655 Context.DeclMustBeEmitted(FD)) 656 return false; 657 658 } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 659 if (!VD->isFileVarDecl() || 660 VD->getType().isConstant(Context) || 661 Context.DeclMustBeEmitted(VD)) 662 return false; 663 664 if (VD->isStaticDataMember() && 665 VD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 666 return false; 667 668 } else { 669 return false; 670 } 671 672 // Only warn for unused decls internal to the translation unit. 673 if (D->getLinkage() == ExternalLinkage) 674 return false; 675 676 return true; 677} 678 679void Sema::MarkUnusedFileScopedDecl(const DeclaratorDecl *D) { 680 if (!D) 681 return; 682 683 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 684 const FunctionDecl *First = FD->getFirstDeclaration(); 685 if (FD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 686 return; // First should already be in the vector. 687 } 688 689 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 690 const VarDecl *First = VD->getFirstDeclaration(); 691 if (VD != First && ShouldWarnIfUnusedFileScopedDecl(First)) 692 return; // First should already be in the vector. 693 } 694 695 if (ShouldWarnIfUnusedFileScopedDecl(D)) 696 UnusedFileScopedDecls.push_back(D); 697 } 698 699static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 700 if (D->isInvalidDecl()) 701 return false; 702 703 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 704 return false; 705 706 if (isa<LabelDecl>(D)) 707 return true; 708 709 // White-list anything that isn't a local variable. 710 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 711 !D->getDeclContext()->isFunctionOrMethod()) 712 return false; 713 714 // Types of valid local variables should be complete, so this should succeed. 715 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 716 717 // White-list anything with an __attribute__((unused)) type. 718 QualType Ty = VD->getType(); 719 720 // Only look at the outermost level of typedef. 721 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 722 if (TT->getDecl()->hasAttr<UnusedAttr>()) 723 return false; 724 } 725 726 // If we failed to complete the type for some reason, or if the type is 727 // dependent, don't diagnose the variable. 728 if (Ty->isIncompleteType() || Ty->isDependentType()) 729 return false; 730 731 if (const TagType *TT = Ty->getAs<TagType>()) { 732 const TagDecl *Tag = TT->getDecl(); 733 if (Tag->hasAttr<UnusedAttr>()) 734 return false; 735 736 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 737 // FIXME: Checking for the presence of a user-declared constructor 738 // isn't completely accurate; we'd prefer to check that the initializer 739 // has no side effects. 740 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 741 return false; 742 } 743 } 744 745 // TODO: __attribute__((unused)) templates? 746 } 747 748 return true; 749} 750 751/// DiagnoseUnusedDecl - Emit warnings about declarations that are not used 752/// unless they are marked attr(unused). 753void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 754 if (!ShouldDiagnoseUnusedDecl(D)) 755 return; 756 757 unsigned DiagID; 758 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 759 DiagID = diag::warn_unused_exception_param; 760 else if (isa<LabelDecl>(D)) 761 DiagID = diag::warn_unused_label; 762 else 763 DiagID = diag::warn_unused_variable; 764 765 Diag(D->getLocation(), DiagID) << D->getDeclName(); 766} 767 768static void CheckPoppedLabel(LabelDecl *L, Sema &S) { 769 // Verify that we have no forward references left. If so, there was a goto 770 // or address of a label taken, but no definition of it. Label fwd 771 // definitions are indicated with a null substmt. 772 if (L->getStmt() == 0) 773 S.Diag(L->getLocation(), diag::err_undeclared_label_use) <<L->getDeclName(); 774} 775 776void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 777 if (S->decl_empty()) return; 778 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 779 "Scope shouldn't contain decls!"); 780 781 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 782 I != E; ++I) { 783 Decl *TmpD = (*I); 784 assert(TmpD && "This decl didn't get pushed??"); 785 786 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 787 NamedDecl *D = cast<NamedDecl>(TmpD); 788 789 if (!D->getDeclName()) continue; 790 791 // Diagnose unused variables in this scope. 792 if (!S->hasErrorOccurred()) 793 DiagnoseUnusedDecl(D); 794 795 // If this was a forward reference to a label, verify it was defined. 796 if (LabelDecl *LD = dyn_cast<LabelDecl>(D)) 797 CheckPoppedLabel(LD, *this); 798 799 // Remove this name from our lexical scope. 800 IdResolver.RemoveDecl(D); 801 } 802} 803 804/// \brief Look for an Objective-C class in the translation unit. 805/// 806/// \param Id The name of the Objective-C class we're looking for. If 807/// typo-correction fixes this name, the Id will be updated 808/// to the fixed name. 809/// 810/// \param IdLoc The location of the name in the translation unit. 811/// 812/// \param TypoCorrection If true, this routine will attempt typo correction 813/// if there is no class with the given name. 814/// 815/// \returns The declaration of the named Objective-C class, or NULL if the 816/// class could not be found. 817ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 818 SourceLocation IdLoc, 819 bool TypoCorrection) { 820 // The third "scope" argument is 0 since we aren't enabling lazy built-in 821 // creation from this context. 822 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 823 824 if (!IDecl && TypoCorrection) { 825 // Perform typo correction at the given location, but only if we 826 // find an Objective-C class name. 827 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 828 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 829 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 830 Diag(IdLoc, diag::err_undef_interface_suggest) 831 << Id << IDecl->getDeclName() 832 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 833 Diag(IDecl->getLocation(), diag::note_previous_decl) 834 << IDecl->getDeclName(); 835 836 Id = IDecl->getIdentifier(); 837 } 838 } 839 840 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 841} 842 843/// getNonFieldDeclScope - Retrieves the innermost scope, starting 844/// from S, where a non-field would be declared. This routine copes 845/// with the difference between C and C++ scoping rules in structs and 846/// unions. For example, the following code is well-formed in C but 847/// ill-formed in C++: 848/// @code 849/// struct S6 { 850/// enum { BAR } e; 851/// }; 852/// 853/// void test_S6() { 854/// struct S6 a; 855/// a.e = BAR; 856/// } 857/// @endcode 858/// For the declaration of BAR, this routine will return a different 859/// scope. The scope S will be the scope of the unnamed enumeration 860/// within S6. In C++, this routine will return the scope associated 861/// with S6, because the enumeration's scope is a transparent 862/// context but structures can contain non-field names. In C, this 863/// routine will return the translation unit scope, since the 864/// enumeration's scope is a transparent context and structures cannot 865/// contain non-field names. 866Scope *Sema::getNonFieldDeclScope(Scope *S) { 867 while (((S->getFlags() & Scope::DeclScope) == 0) || 868 (S->getEntity() && 869 ((DeclContext *)S->getEntity())->isTransparentContext()) || 870 (S->isClassScope() && !getLangOptions().CPlusPlus)) 871 S = S->getParent(); 872 return S; 873} 874 875/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 876/// file scope. lazily create a decl for it. ForRedeclaration is true 877/// if we're creating this built-in in anticipation of redeclaring the 878/// built-in. 879NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 880 Scope *S, bool ForRedeclaration, 881 SourceLocation Loc) { 882 Builtin::ID BID = (Builtin::ID)bid; 883 884 ASTContext::GetBuiltinTypeError Error; 885 QualType R = Context.GetBuiltinType(BID, Error); 886 switch (Error) { 887 case ASTContext::GE_None: 888 // Okay 889 break; 890 891 case ASTContext::GE_Missing_stdio: 892 if (ForRedeclaration) 893 Diag(Loc, diag::warn_implicit_decl_requires_stdio) 894 << Context.BuiltinInfo.GetName(BID); 895 return 0; 896 897 case ASTContext::GE_Missing_setjmp: 898 if (ForRedeclaration) 899 Diag(Loc, diag::warn_implicit_decl_requires_setjmp) 900 << Context.BuiltinInfo.GetName(BID); 901 return 0; 902 } 903 904 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 905 Diag(Loc, diag::ext_implicit_lib_function_decl) 906 << Context.BuiltinInfo.GetName(BID) 907 << R; 908 if (Context.BuiltinInfo.getHeaderName(BID) && 909 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl, Loc) 910 != Diagnostic::Ignored) 911 Diag(Loc, diag::note_please_include_header) 912 << Context.BuiltinInfo.getHeaderName(BID) 913 << Context.BuiltinInfo.GetName(BID); 914 } 915 916 FunctionDecl *New = FunctionDecl::Create(Context, 917 Context.getTranslationUnitDecl(), 918 Loc, Loc, II, R, /*TInfo=*/0, 919 SC_Extern, 920 SC_None, false, 921 /*hasPrototype=*/true); 922 New->setImplicit(); 923 924 // Create Decl objects for each parameter, adding them to the 925 // FunctionDecl. 926 if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 927 llvm::SmallVector<ParmVarDecl*, 16> Params; 928 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 929 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 930 SourceLocation(), 0, 931 FT->getArgType(i), /*TInfo=*/0, 932 SC_None, SC_None, 0)); 933 New->setParams(Params.data(), Params.size()); 934 } 935 936 AddKnownFunctionAttributes(New); 937 938 // TUScope is the translation-unit scope to insert this function into. 939 // FIXME: This is hideous. We need to teach PushOnScopeChains to 940 // relate Scopes to DeclContexts, and probably eliminate CurContext 941 // entirely, but we're not there yet. 942 DeclContext *SavedContext = CurContext; 943 CurContext = Context.getTranslationUnitDecl(); 944 PushOnScopeChains(New, TUScope); 945 CurContext = SavedContext; 946 return New; 947} 948 949/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 950/// same name and scope as a previous declaration 'Old'. Figure out 951/// how to resolve this situation, merging decls or emitting 952/// diagnostics as appropriate. If there was an error, set New to be invalid. 953/// 954void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 955 // If the new decl is known invalid already, don't bother doing any 956 // merging checks. 957 if (New->isInvalidDecl()) return; 958 959 // Allow multiple definitions for ObjC built-in typedefs. 960 // FIXME: Verify the underlying types are equivalent! 961 if (getLangOptions().ObjC1) { 962 const IdentifierInfo *TypeID = New->getIdentifier(); 963 switch (TypeID->getLength()) { 964 default: break; 965 case 2: 966 if (!TypeID->isStr("id")) 967 break; 968 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 969 // Install the built-in type for 'id', ignoring the current definition. 970 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 971 return; 972 case 5: 973 if (!TypeID->isStr("Class")) 974 break; 975 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 976 // Install the built-in type for 'Class', ignoring the current definition. 977 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 978 return; 979 case 3: 980 if (!TypeID->isStr("SEL")) 981 break; 982 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 983 // Install the built-in type for 'SEL', ignoring the current definition. 984 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 985 return; 986 case 8: 987 if (!TypeID->isStr("Protocol")) 988 break; 989 Context.setObjCProtoType(New->getUnderlyingType()); 990 return; 991 } 992 // Fall through - the typedef name was not a builtin type. 993 } 994 995 // Verify the old decl was also a type. 996 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 997 if (!Old) { 998 Diag(New->getLocation(), diag::err_redefinition_different_kind) 999 << New->getDeclName(); 1000 1001 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 1002 if (OldD->getLocation().isValid()) 1003 Diag(OldD->getLocation(), diag::note_previous_definition); 1004 1005 return New->setInvalidDecl(); 1006 } 1007 1008 // If the old declaration is invalid, just give up here. 1009 if (Old->isInvalidDecl()) 1010 return New->setInvalidDecl(); 1011 1012 // Determine the "old" type we'll use for checking and diagnostics. 1013 QualType OldType; 1014 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 1015 OldType = OldTypedef->getUnderlyingType(); 1016 else 1017 OldType = Context.getTypeDeclType(Old); 1018 1019 // If the typedef types are not identical, reject them in all languages and 1020 // with any extensions enabled. 1021 1022 if (OldType != New->getUnderlyingType() && 1023 Context.getCanonicalType(OldType) != 1024 Context.getCanonicalType(New->getUnderlyingType())) { 1025 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 1026 << New->getUnderlyingType() << OldType; 1027 if (Old->getLocation().isValid()) 1028 Diag(Old->getLocation(), diag::note_previous_definition); 1029 return New->setInvalidDecl(); 1030 } 1031 1032 // The types match. Link up the redeclaration chain if the old 1033 // declaration was a typedef. 1034 // FIXME: this is a potential source of wierdness if the type 1035 // spellings don't match exactly. 1036 if (isa<TypedefDecl>(Old)) 1037 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 1038 1039 if (getLangOptions().Microsoft) 1040 return; 1041 1042 if (getLangOptions().CPlusPlus) { 1043 // C++ [dcl.typedef]p2: 1044 // In a given non-class scope, a typedef specifier can be used to 1045 // redefine the name of any type declared in that scope to refer 1046 // to the type to which it already refers. 1047 if (!isa<CXXRecordDecl>(CurContext)) 1048 return; 1049 1050 // C++0x [dcl.typedef]p4: 1051 // In a given class scope, a typedef specifier can be used to redefine 1052 // any class-name declared in that scope that is not also a typedef-name 1053 // to refer to the type to which it already refers. 1054 // 1055 // This wording came in via DR424, which was a correction to the 1056 // wording in DR56, which accidentally banned code like: 1057 // 1058 // struct S { 1059 // typedef struct A { } A; 1060 // }; 1061 // 1062 // in the C++03 standard. We implement the C++0x semantics, which 1063 // allow the above but disallow 1064 // 1065 // struct S { 1066 // typedef int I; 1067 // typedef int I; 1068 // }; 1069 // 1070 // since that was the intent of DR56. 1071 if (!isa<TypedefDecl >(Old)) 1072 return; 1073 1074 Diag(New->getLocation(), diag::err_redefinition) 1075 << New->getDeclName(); 1076 Diag(Old->getLocation(), diag::note_previous_definition); 1077 return New->setInvalidDecl(); 1078 } 1079 1080 // If we have a redefinition of a typedef in C, emit a warning. This warning 1081 // is normally mapped to an error, but can be controlled with 1082 // -Wtypedef-redefinition. If either the original or the redefinition is 1083 // in a system header, don't emit this for compatibility with GCC. 1084 if (getDiagnostics().getSuppressSystemWarnings() && 1085 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 1086 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 1087 return; 1088 1089 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 1090 << New->getDeclName(); 1091 Diag(Old->getLocation(), diag::note_previous_definition); 1092 return; 1093} 1094 1095/// DeclhasAttr - returns true if decl Declaration already has the target 1096/// attribute. 1097static bool 1098DeclHasAttr(const Decl *D, const Attr *A) { 1099 const OwnershipAttr *OA = dyn_cast<OwnershipAttr>(A); 1100 for (Decl::attr_iterator i = D->attr_begin(), e = D->attr_end(); i != e; ++i) 1101 if ((*i)->getKind() == A->getKind()) { 1102 // FIXME: Don't hardcode this check 1103 if (OA && isa<OwnershipAttr>(*i)) 1104 return OA->getOwnKind() == cast<OwnershipAttr>(*i)->getOwnKind(); 1105 return true; 1106 } 1107 1108 return false; 1109} 1110 1111/// mergeDeclAttributes - Copy attributes from the Old decl to the New one. 1112static void mergeDeclAttributes(Decl *newDecl, const Decl *oldDecl, 1113 ASTContext &C) { 1114 if (!oldDecl->hasAttrs()) 1115 return; 1116 1117 bool foundAny = newDecl->hasAttrs(); 1118 1119 // Ensure that any moving of objects within the allocated map is done before 1120 // we process them. 1121 if (!foundAny) newDecl->setAttrs(AttrVec()); 1122 1123 for (specific_attr_iterator<InheritableAttr> 1124 i = oldDecl->specific_attr_begin<InheritableAttr>(), 1125 e = oldDecl->specific_attr_end<InheritableAttr>(); i != e; ++i) { 1126 if (!DeclHasAttr(newDecl, *i)) { 1127 InheritableAttr *newAttr = cast<InheritableAttr>((*i)->clone(C)); 1128 newAttr->setInherited(true); 1129 newDecl->addAttr(newAttr); 1130 foundAny = true; 1131 } 1132 } 1133 1134 if (!foundAny) newDecl->dropAttrs(); 1135} 1136 1137/// mergeParamDeclAttributes - Copy attributes from the old parameter 1138/// to the new one. 1139static void mergeParamDeclAttributes(ParmVarDecl *newDecl, 1140 const ParmVarDecl *oldDecl, 1141 ASTContext &C) { 1142 if (!oldDecl->hasAttrs()) 1143 return; 1144 1145 bool foundAny = newDecl->hasAttrs(); 1146 1147 // Ensure that any moving of objects within the allocated map is 1148 // done before we process them. 1149 if (!foundAny) newDecl->setAttrs(AttrVec()); 1150 1151 for (specific_attr_iterator<InheritableParamAttr> 1152 i = oldDecl->specific_attr_begin<InheritableParamAttr>(), 1153 e = oldDecl->specific_attr_end<InheritableParamAttr>(); i != e; ++i) { 1154 if (!DeclHasAttr(newDecl, *i)) { 1155 InheritableAttr *newAttr = cast<InheritableParamAttr>((*i)->clone(C)); 1156 newAttr->setInherited(true); 1157 newDecl->addAttr(newAttr); 1158 foundAny = true; 1159 } 1160 } 1161 1162 if (!foundAny) newDecl->dropAttrs(); 1163} 1164 1165namespace { 1166 1167/// Used in MergeFunctionDecl to keep track of function parameters in 1168/// C. 1169struct GNUCompatibleParamWarning { 1170 ParmVarDecl *OldParm; 1171 ParmVarDecl *NewParm; 1172 QualType PromotedType; 1173}; 1174 1175} 1176 1177/// getSpecialMember - get the special member enum for a method. 1178Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 1179 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 1180 if (Ctor->isCopyConstructor()) 1181 return Sema::CXXCopyConstructor; 1182 1183 return Sema::CXXConstructor; 1184 } 1185 1186 if (isa<CXXDestructorDecl>(MD)) 1187 return Sema::CXXDestructor; 1188 1189 assert(MD->isCopyAssignmentOperator() && 1190 "Must have copy assignment operator"); 1191 return Sema::CXXCopyAssignment; 1192} 1193 1194/// canRedefineFunction - checks if a function can be redefined. Currently, 1195/// only extern inline functions can be redefined, and even then only in 1196/// GNU89 mode. 1197static bool canRedefineFunction(const FunctionDecl *FD, 1198 const LangOptions& LangOpts) { 1199 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 1200 FD->isInlineSpecified() && 1201 FD->getStorageClass() == SC_Extern); 1202} 1203 1204/// MergeFunctionDecl - We just parsed a function 'New' from 1205/// declarator D which has the same name and scope as a previous 1206/// declaration 'Old'. Figure out how to resolve this situation, 1207/// merging decls or emitting diagnostics as appropriate. 1208/// 1209/// In C++, New and Old must be declarations that are not 1210/// overloaded. Use IsOverload to determine whether New and Old are 1211/// overloaded, and to select the Old declaration that New should be 1212/// merged with. 1213/// 1214/// Returns true if there was an error, false otherwise. 1215bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 1216 // Verify the old decl was also a function. 1217 FunctionDecl *Old = 0; 1218 if (FunctionTemplateDecl *OldFunctionTemplate 1219 = dyn_cast<FunctionTemplateDecl>(OldD)) 1220 Old = OldFunctionTemplate->getTemplatedDecl(); 1221 else 1222 Old = dyn_cast<FunctionDecl>(OldD); 1223 if (!Old) { 1224 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 1225 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 1226 Diag(Shadow->getTargetDecl()->getLocation(), 1227 diag::note_using_decl_target); 1228 Diag(Shadow->getUsingDecl()->getLocation(), 1229 diag::note_using_decl) << 0; 1230 return true; 1231 } 1232 1233 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1234 << New->getDeclName(); 1235 Diag(OldD->getLocation(), diag::note_previous_definition); 1236 return true; 1237 } 1238 1239 // Determine whether the previous declaration was a definition, 1240 // implicit declaration, or a declaration. 1241 diag::kind PrevDiag; 1242 if (Old->isThisDeclarationADefinition()) 1243 PrevDiag = diag::note_previous_definition; 1244 else if (Old->isImplicit()) 1245 PrevDiag = diag::note_previous_implicit_declaration; 1246 else 1247 PrevDiag = diag::note_previous_declaration; 1248 1249 QualType OldQType = Context.getCanonicalType(Old->getType()); 1250 QualType NewQType = Context.getCanonicalType(New->getType()); 1251 1252 // Don't complain about this if we're in GNU89 mode and the old function 1253 // is an extern inline function. 1254 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1255 New->getStorageClass() == SC_Static && 1256 Old->getStorageClass() != SC_Static && 1257 !canRedefineFunction(Old, getLangOptions())) { 1258 Diag(New->getLocation(), diag::err_static_non_static) 1259 << New; 1260 Diag(Old->getLocation(), PrevDiag); 1261 return true; 1262 } 1263 1264 // If a function is first declared with a calling convention, but is 1265 // later declared or defined without one, the second decl assumes the 1266 // calling convention of the first. 1267 // 1268 // For the new decl, we have to look at the NON-canonical type to tell the 1269 // difference between a function that really doesn't have a calling 1270 // convention and one that is declared cdecl. That's because in 1271 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1272 // because it is the default calling convention. 1273 // 1274 // Note also that we DO NOT return at this point, because we still have 1275 // other tests to run. 1276 const FunctionType *OldType = cast<FunctionType>(OldQType); 1277 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1278 FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1279 FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1280 bool RequiresAdjustment = false; 1281 if (OldTypeInfo.getCC() != CC_Default && 1282 NewTypeInfo.getCC() == CC_Default) { 1283 NewTypeInfo = NewTypeInfo.withCallingConv(OldTypeInfo.getCC()); 1284 RequiresAdjustment = true; 1285 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1286 NewTypeInfo.getCC())) { 1287 // Calling conventions really aren't compatible, so complain. 1288 Diag(New->getLocation(), diag::err_cconv_change) 1289 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1290 << (OldTypeInfo.getCC() == CC_Default) 1291 << (OldTypeInfo.getCC() == CC_Default ? "" : 1292 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1293 Diag(Old->getLocation(), diag::note_previous_declaration); 1294 return true; 1295 } 1296 1297 // FIXME: diagnose the other way around? 1298 if (OldTypeInfo.getNoReturn() && !NewTypeInfo.getNoReturn()) { 1299 NewTypeInfo = NewTypeInfo.withNoReturn(true); 1300 RequiresAdjustment = true; 1301 } 1302 1303 // Merge regparm attribute. 1304 if (OldTypeInfo.getHasRegParm() != NewTypeInfo.getHasRegParm() || 1305 OldTypeInfo.getRegParm() != NewTypeInfo.getRegParm()) { 1306 if (NewTypeInfo.getHasRegParm()) { 1307 Diag(New->getLocation(), diag::err_regparm_mismatch) 1308 << NewType->getRegParmType() 1309 << OldType->getRegParmType(); 1310 Diag(Old->getLocation(), diag::note_previous_declaration); 1311 return true; 1312 } 1313 1314 NewTypeInfo = NewTypeInfo.withRegParm(OldTypeInfo.getRegParm()); 1315 RequiresAdjustment = true; 1316 } 1317 1318 if (RequiresAdjustment) { 1319 NewType = Context.adjustFunctionType(NewType, NewTypeInfo); 1320 New->setType(QualType(NewType, 0)); 1321 NewQType = Context.getCanonicalType(New->getType()); 1322 } 1323 1324 if (getLangOptions().CPlusPlus) { 1325 // (C++98 13.1p2): 1326 // Certain function declarations cannot be overloaded: 1327 // -- Function declarations that differ only in the return type 1328 // cannot be overloaded. 1329 QualType OldReturnType = OldType->getResultType(); 1330 QualType NewReturnType = cast<FunctionType>(NewQType)->getResultType(); 1331 QualType ResQT; 1332 if (OldReturnType != NewReturnType) { 1333 if (NewReturnType->isObjCObjectPointerType() 1334 && OldReturnType->isObjCObjectPointerType()) 1335 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1336 if (ResQT.isNull()) { 1337 if (New->isCXXClassMember() && New->isOutOfLine()) 1338 Diag(New->getLocation(), 1339 diag::err_member_def_does_not_match_ret_type) << New; 1340 else 1341 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1342 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1343 return true; 1344 } 1345 else 1346 NewQType = ResQT; 1347 } 1348 1349 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1350 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1351 if (OldMethod && NewMethod) { 1352 // Preserve triviality. 1353 NewMethod->setTrivial(OldMethod->isTrivial()); 1354 1355 bool isFriend = NewMethod->getFriendObjectKind(); 1356 1357 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1358 // -- Member function declarations with the same name and the 1359 // same parameter types cannot be overloaded if any of them 1360 // is a static member function declaration. 1361 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1362 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1363 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1364 return true; 1365 } 1366 1367 // C++ [class.mem]p1: 1368 // [...] A member shall not be declared twice in the 1369 // member-specification, except that a nested class or member 1370 // class template can be declared and then later defined. 1371 unsigned NewDiag; 1372 if (isa<CXXConstructorDecl>(OldMethod)) 1373 NewDiag = diag::err_constructor_redeclared; 1374 else if (isa<CXXDestructorDecl>(NewMethod)) 1375 NewDiag = diag::err_destructor_redeclared; 1376 else if (isa<CXXConversionDecl>(NewMethod)) 1377 NewDiag = diag::err_conv_function_redeclared; 1378 else 1379 NewDiag = diag::err_member_redeclared; 1380 1381 Diag(New->getLocation(), NewDiag); 1382 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1383 1384 // Complain if this is an explicit declaration of a special 1385 // member that was initially declared implicitly. 1386 // 1387 // As an exception, it's okay to befriend such methods in order 1388 // to permit the implicit constructor/destructor/operator calls. 1389 } else if (OldMethod->isImplicit()) { 1390 if (isFriend) { 1391 NewMethod->setImplicit(); 1392 } else { 1393 Diag(NewMethod->getLocation(), 1394 diag::err_definition_of_implicitly_declared_member) 1395 << New << getSpecialMember(OldMethod); 1396 return true; 1397 } 1398 } 1399 } 1400 1401 // (C++98 8.3.5p3): 1402 // All declarations for a function shall agree exactly in both the 1403 // return type and the parameter-type-list. 1404 // We also want to respect all the extended bits except noreturn. 1405 1406 // noreturn should now match unless the old type info didn't have it. 1407 QualType OldQTypeForComparison = OldQType; 1408 if (!OldTypeInfo.getNoReturn() && NewTypeInfo.getNoReturn()) { 1409 assert(OldQType == QualType(OldType, 0)); 1410 const FunctionType *OldTypeForComparison 1411 = Context.adjustFunctionType(OldType, OldTypeInfo.withNoReturn(true)); 1412 OldQTypeForComparison = QualType(OldTypeForComparison, 0); 1413 assert(OldQTypeForComparison.isCanonical()); 1414 } 1415 1416 if (OldQTypeForComparison == NewQType) 1417 return MergeCompatibleFunctionDecls(New, Old); 1418 1419 // Fall through for conflicting redeclarations and redefinitions. 1420 } 1421 1422 // C: Function types need to be compatible, not identical. This handles 1423 // duplicate function decls like "void f(int); void f(enum X);" properly. 1424 if (!getLangOptions().CPlusPlus && 1425 Context.typesAreCompatible(OldQType, NewQType)) { 1426 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1427 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1428 const FunctionProtoType *OldProto = 0; 1429 if (isa<FunctionNoProtoType>(NewFuncType) && 1430 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1431 // The old declaration provided a function prototype, but the 1432 // new declaration does not. Merge in the prototype. 1433 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1434 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1435 OldProto->arg_type_end()); 1436 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1437 ParamTypes.data(), ParamTypes.size(), 1438 OldProto->getExtProtoInfo()); 1439 New->setType(NewQType); 1440 New->setHasInheritedPrototype(); 1441 1442 // Synthesize a parameter for each argument type. 1443 llvm::SmallVector<ParmVarDecl*, 16> Params; 1444 for (FunctionProtoType::arg_type_iterator 1445 ParamType = OldProto->arg_type_begin(), 1446 ParamEnd = OldProto->arg_type_end(); 1447 ParamType != ParamEnd; ++ParamType) { 1448 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1449 SourceLocation(), 1450 SourceLocation(), 0, 1451 *ParamType, /*TInfo=*/0, 1452 SC_None, SC_None, 1453 0); 1454 Param->setImplicit(); 1455 Params.push_back(Param); 1456 } 1457 1458 New->setParams(Params.data(), Params.size()); 1459 } 1460 1461 return MergeCompatibleFunctionDecls(New, Old); 1462 } 1463 1464 // GNU C permits a K&R definition to follow a prototype declaration 1465 // if the declared types of the parameters in the K&R definition 1466 // match the types in the prototype declaration, even when the 1467 // promoted types of the parameters from the K&R definition differ 1468 // from the types in the prototype. GCC then keeps the types from 1469 // the prototype. 1470 // 1471 // If a variadic prototype is followed by a non-variadic K&R definition, 1472 // the K&R definition becomes variadic. This is sort of an edge case, but 1473 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1474 // C99 6.9.1p8. 1475 if (!getLangOptions().CPlusPlus && 1476 Old->hasPrototype() && !New->hasPrototype() && 1477 New->getType()->getAs<FunctionProtoType>() && 1478 Old->getNumParams() == New->getNumParams()) { 1479 llvm::SmallVector<QualType, 16> ArgTypes; 1480 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1481 const FunctionProtoType *OldProto 1482 = Old->getType()->getAs<FunctionProtoType>(); 1483 const FunctionProtoType *NewProto 1484 = New->getType()->getAs<FunctionProtoType>(); 1485 1486 // Determine whether this is the GNU C extension. 1487 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1488 NewProto->getResultType()); 1489 bool LooseCompatible = !MergedReturn.isNull(); 1490 for (unsigned Idx = 0, End = Old->getNumParams(); 1491 LooseCompatible && Idx != End; ++Idx) { 1492 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1493 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1494 if (Context.typesAreCompatible(OldParm->getType(), 1495 NewProto->getArgType(Idx))) { 1496 ArgTypes.push_back(NewParm->getType()); 1497 } else if (Context.typesAreCompatible(OldParm->getType(), 1498 NewParm->getType(), 1499 /*CompareUnqualified=*/true)) { 1500 GNUCompatibleParamWarning Warn 1501 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1502 Warnings.push_back(Warn); 1503 ArgTypes.push_back(NewParm->getType()); 1504 } else 1505 LooseCompatible = false; 1506 } 1507 1508 if (LooseCompatible) { 1509 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1510 Diag(Warnings[Warn].NewParm->getLocation(), 1511 diag::ext_param_promoted_not_compatible_with_prototype) 1512 << Warnings[Warn].PromotedType 1513 << Warnings[Warn].OldParm->getType(); 1514 if (Warnings[Warn].OldParm->getLocation().isValid()) 1515 Diag(Warnings[Warn].OldParm->getLocation(), 1516 diag::note_previous_declaration); 1517 } 1518 1519 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1520 ArgTypes.size(), 1521 OldProto->getExtProtoInfo())); 1522 return MergeCompatibleFunctionDecls(New, Old); 1523 } 1524 1525 // Fall through to diagnose conflicting types. 1526 } 1527 1528 // A function that has already been declared has been redeclared or defined 1529 // with a different type- show appropriate diagnostic 1530 if (unsigned BuiltinID = Old->getBuiltinID()) { 1531 // The user has declared a builtin function with an incompatible 1532 // signature. 1533 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1534 // The function the user is redeclaring is a library-defined 1535 // function like 'malloc' or 'printf'. Warn about the 1536 // redeclaration, then pretend that we don't know about this 1537 // library built-in. 1538 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1539 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1540 << Old << Old->getType(); 1541 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1542 Old->setInvalidDecl(); 1543 return false; 1544 } 1545 1546 PrevDiag = diag::note_previous_builtin_declaration; 1547 } 1548 1549 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1550 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1551 return true; 1552} 1553 1554/// \brief Completes the merge of two function declarations that are 1555/// known to be compatible. 1556/// 1557/// This routine handles the merging of attributes and other 1558/// properties of function declarations form the old declaration to 1559/// the new declaration, once we know that New is in fact a 1560/// redeclaration of Old. 1561/// 1562/// \returns false 1563bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1564 // Merge the attributes 1565 mergeDeclAttributes(New, Old, Context); 1566 1567 // Merge the storage class. 1568 if (Old->getStorageClass() != SC_Extern && 1569 Old->getStorageClass() != SC_None) 1570 New->setStorageClass(Old->getStorageClass()); 1571 1572 // Merge "pure" flag. 1573 if (Old->isPure()) 1574 New->setPure(); 1575 1576 // Merge the "deleted" flag. 1577 if (Old->isDeleted()) 1578 New->setDeleted(); 1579 1580 // Merge attributes from the parameters. These can mismatch with K&R 1581 // declarations. 1582 if (New->getNumParams() == Old->getNumParams()) 1583 for (unsigned i = 0, e = New->getNumParams(); i != e; ++i) 1584 mergeParamDeclAttributes(New->getParamDecl(i), Old->getParamDecl(i), 1585 Context); 1586 1587 if (getLangOptions().CPlusPlus) 1588 return MergeCXXFunctionDecl(New, Old); 1589 1590 return false; 1591} 1592 1593void Sema::mergeObjCMethodDecls(ObjCMethodDecl *newMethod, 1594 const ObjCMethodDecl *oldMethod) { 1595 // Merge the attributes. 1596 mergeDeclAttributes(newMethod, oldMethod, Context); 1597 1598 // Merge attributes from the parameters. 1599 for (ObjCMethodDecl::param_iterator oi = oldMethod->param_begin(), 1600 ni = newMethod->param_begin(), ne = newMethod->param_end(); 1601 ni != ne; ++ni, ++oi) 1602 mergeParamDeclAttributes(*ni, *oi, Context); 1603} 1604 1605/// MergeVarDeclTypes - We parsed a variable 'New' which has the same name and 1606/// scope as a previous declaration 'Old'. Figure out how to merge their types, 1607/// emitting diagnostics as appropriate. 1608/// 1609/// Declarations using the auto type specifier (C++ [decl.spec.auto]) call back 1610/// to here in AddInitializerToDecl and AddCXXDirectInitializerToDecl. We can't 1611/// check them before the initializer is attached. 1612/// 1613void Sema::MergeVarDeclTypes(VarDecl *New, VarDecl *Old) { 1614 if (New->isInvalidDecl() || Old->isInvalidDecl()) 1615 return; 1616 1617 QualType MergedT; 1618 if (getLangOptions().CPlusPlus) { 1619 AutoType *AT = New->getType()->getContainedAutoType(); 1620 if (AT && !AT->isDeduced()) { 1621 // We don't know what the new type is until the initializer is attached. 1622 return; 1623 } else if (Context.hasSameType(New->getType(), Old->getType())) { 1624 // These could still be something that needs exception specs checked. 1625 return MergeVarDeclExceptionSpecs(New, Old); 1626 } 1627 // C++ [basic.link]p10: 1628 // [...] the types specified by all declarations referring to a given 1629 // object or function shall be identical, except that declarations for an 1630 // array object can specify array types that differ by the presence or 1631 // absence of a major array bound (8.3.4). 1632 else if (Old->getType()->isIncompleteArrayType() && 1633 New->getType()->isArrayType()) { 1634 CanQual<ArrayType> OldArray 1635 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1636 CanQual<ArrayType> NewArray 1637 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1638 if (OldArray->getElementType() == NewArray->getElementType()) 1639 MergedT = New->getType(); 1640 } else if (Old->getType()->isArrayType() && 1641 New->getType()->isIncompleteArrayType()) { 1642 CanQual<ArrayType> OldArray 1643 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1644 CanQual<ArrayType> NewArray 1645 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1646 if (OldArray->getElementType() == NewArray->getElementType()) 1647 MergedT = Old->getType(); 1648 } else if (New->getType()->isObjCObjectPointerType() 1649 && Old->getType()->isObjCObjectPointerType()) { 1650 MergedT = Context.mergeObjCGCQualifiers(New->getType(), 1651 Old->getType()); 1652 } 1653 } else { 1654 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1655 } 1656 if (MergedT.isNull()) { 1657 Diag(New->getLocation(), diag::err_redefinition_different_type) 1658 << New->getDeclName(); 1659 Diag(Old->getLocation(), diag::note_previous_definition); 1660 return New->setInvalidDecl(); 1661 } 1662 New->setType(MergedT); 1663} 1664 1665/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1666/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1667/// situation, merging decls or emitting diagnostics as appropriate. 1668/// 1669/// Tentative definition rules (C99 6.9.2p2) are checked by 1670/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1671/// definitions here, since the initializer hasn't been attached. 1672/// 1673void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1674 // If the new decl is already invalid, don't do any other checking. 1675 if (New->isInvalidDecl()) 1676 return; 1677 1678 // Verify the old decl was also a variable. 1679 VarDecl *Old = 0; 1680 if (!Previous.isSingleResult() || 1681 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1682 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1683 << New->getDeclName(); 1684 Diag(Previous.getRepresentativeDecl()->getLocation(), 1685 diag::note_previous_definition); 1686 return New->setInvalidDecl(); 1687 } 1688 1689 // C++ [class.mem]p1: 1690 // A member shall not be declared twice in the member-specification [...] 1691 // 1692 // Here, we need only consider static data members. 1693 if (Old->isStaticDataMember() && !New->isOutOfLine()) { 1694 Diag(New->getLocation(), diag::err_duplicate_member) 1695 << New->getIdentifier(); 1696 Diag(Old->getLocation(), diag::note_previous_declaration); 1697 New->setInvalidDecl(); 1698 } 1699 1700 mergeDeclAttributes(New, Old, Context); 1701 1702 // Merge the types. 1703 MergeVarDeclTypes(New, Old); 1704 if (New->isInvalidDecl()) 1705 return; 1706 1707 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1708 if (New->getStorageClass() == SC_Static && 1709 (Old->getStorageClass() == SC_None || Old->hasExternalStorage())) { 1710 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1711 Diag(Old->getLocation(), diag::note_previous_definition); 1712 return New->setInvalidDecl(); 1713 } 1714 // C99 6.2.2p4: 1715 // For an identifier declared with the storage-class specifier 1716 // extern in a scope in which a prior declaration of that 1717 // identifier is visible,23) if the prior declaration specifies 1718 // internal or external linkage, the linkage of the identifier at 1719 // the later declaration is the same as the linkage specified at 1720 // the prior declaration. If no prior declaration is visible, or 1721 // if the prior declaration specifies no linkage, then the 1722 // identifier has external linkage. 1723 if (New->hasExternalStorage() && Old->hasLinkage()) 1724 /* Okay */; 1725 else if (New->getStorageClass() != SC_Static && 1726 Old->getStorageClass() == SC_Static) { 1727 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1728 Diag(Old->getLocation(), diag::note_previous_definition); 1729 return New->setInvalidDecl(); 1730 } 1731 1732 // Check if extern is followed by non-extern and vice-versa. 1733 if (New->hasExternalStorage() && 1734 !Old->hasLinkage() && Old->isLocalVarDecl()) { 1735 Diag(New->getLocation(), diag::err_extern_non_extern) << New->getDeclName(); 1736 Diag(Old->getLocation(), diag::note_previous_definition); 1737 return New->setInvalidDecl(); 1738 } 1739 if (Old->hasExternalStorage() && 1740 !New->hasLinkage() && New->isLocalVarDecl()) { 1741 Diag(New->getLocation(), diag::err_non_extern_extern) << New->getDeclName(); 1742 Diag(Old->getLocation(), diag::note_previous_definition); 1743 return New->setInvalidDecl(); 1744 } 1745 1746 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1747 1748 // FIXME: The test for external storage here seems wrong? We still 1749 // need to check for mismatches. 1750 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1751 // Don't complain about out-of-line definitions of static members. 1752 !(Old->getLexicalDeclContext()->isRecord() && 1753 !New->getLexicalDeclContext()->isRecord())) { 1754 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1755 Diag(Old->getLocation(), diag::note_previous_definition); 1756 return New->setInvalidDecl(); 1757 } 1758 1759 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1760 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1761 Diag(Old->getLocation(), diag::note_previous_definition); 1762 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1763 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1764 Diag(Old->getLocation(), diag::note_previous_definition); 1765 } 1766 1767 // C++ doesn't have tentative definitions, so go right ahead and check here. 1768 const VarDecl *Def; 1769 if (getLangOptions().CPlusPlus && 1770 New->isThisDeclarationADefinition() == VarDecl::Definition && 1771 (Def = Old->getDefinition())) { 1772 Diag(New->getLocation(), diag::err_redefinition) 1773 << New->getDeclName(); 1774 Diag(Def->getLocation(), diag::note_previous_definition); 1775 New->setInvalidDecl(); 1776 return; 1777 } 1778 // c99 6.2.2 P4. 1779 // For an identifier declared with the storage-class specifier extern in a 1780 // scope in which a prior declaration of that identifier is visible, if 1781 // the prior declaration specifies internal or external linkage, the linkage 1782 // of the identifier at the later declaration is the same as the linkage 1783 // specified at the prior declaration. 1784 // FIXME. revisit this code. 1785 if (New->hasExternalStorage() && 1786 Old->getLinkage() == InternalLinkage && 1787 New->getDeclContext() == Old->getDeclContext()) 1788 New->setStorageClass(Old->getStorageClass()); 1789 1790 // Keep a chain of previous declarations. 1791 New->setPreviousDeclaration(Old); 1792 1793 // Inherit access appropriately. 1794 New->setAccess(Old->getAccess()); 1795} 1796 1797/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1798/// no declarator (e.g. "struct foo;") is parsed. 1799Decl *Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1800 DeclSpec &DS) { 1801 Decl *TagD = 0; 1802 TagDecl *Tag = 0; 1803 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1804 DS.getTypeSpecType() == DeclSpec::TST_struct || 1805 DS.getTypeSpecType() == DeclSpec::TST_union || 1806 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1807 TagD = DS.getRepAsDecl(); 1808 1809 if (!TagD) // We probably had an error 1810 return 0; 1811 1812 // Note that the above type specs guarantee that the 1813 // type rep is a Decl, whereas in many of the others 1814 // it's a Type. 1815 Tag = dyn_cast<TagDecl>(TagD); 1816 } 1817 1818 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1819 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1820 // or incomplete types shall not be restrict-qualified." 1821 if (TypeQuals & DeclSpec::TQ_restrict) 1822 Diag(DS.getRestrictSpecLoc(), 1823 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1824 << DS.getSourceRange(); 1825 } 1826 1827 if (DS.isFriendSpecified()) { 1828 // If we're dealing with a decl but not a TagDecl, assume that 1829 // whatever routines created it handled the friendship aspect. 1830 if (TagD && !Tag) 1831 return 0; 1832 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1833 } 1834 1835 // Track whether we warned about the fact that there aren't any 1836 // declarators. 1837 bool emittedWarning = false; 1838 1839 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1840 ProcessDeclAttributeList(S, Record, DS.getAttributes().getList()); 1841 1842 if (!Record->getDeclName() && Record->isDefinition() && 1843 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1844 if (getLangOptions().CPlusPlus || 1845 Record->getDeclContext()->isRecord()) 1846 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1847 1848 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1849 << DS.getSourceRange(); 1850 emittedWarning = true; 1851 } 1852 } 1853 1854 // Check for Microsoft C extension: anonymous struct. 1855 if (getLangOptions().Microsoft && !getLangOptions().CPlusPlus && 1856 CurContext->isRecord() && 1857 DS.getStorageClassSpec() == DeclSpec::SCS_unspecified) { 1858 // Handle 2 kinds of anonymous struct: 1859 // struct STRUCT; 1860 // and 1861 // STRUCT_TYPE; <- where STRUCT_TYPE is a typedef struct. 1862 RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag); 1863 if ((Record && Record->getDeclName() && !Record->isDefinition()) || 1864 (DS.getTypeSpecType() == DeclSpec::TST_typename && 1865 DS.getRepAsType().get()->isStructureType())) { 1866 Diag(DS.getSourceRange().getBegin(), diag::ext_ms_anonymous_struct) 1867 << DS.getSourceRange(); 1868 return BuildMicrosoftCAnonymousStruct(S, DS, Record); 1869 } 1870 } 1871 1872 if (getLangOptions().CPlusPlus && 1873 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1874 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1875 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1876 !Enum->getIdentifier() && !Enum->isInvalidDecl()) { 1877 Diag(Enum->getLocation(), diag::ext_no_declarators) 1878 << DS.getSourceRange(); 1879 emittedWarning = true; 1880 } 1881 1882 // Skip all the checks below if we have a type error. 1883 if (DS.getTypeSpecType() == DeclSpec::TST_error) return TagD; 1884 1885 if (!DS.isMissingDeclaratorOk()) { 1886 // Warn about typedefs of enums without names, since this is an 1887 // extension in both Microsoft and GNU. 1888 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1889 Tag && isa<EnumDecl>(Tag)) { 1890 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1891 << DS.getSourceRange(); 1892 return Tag; 1893 } 1894 1895 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1896 << DS.getSourceRange(); 1897 emittedWarning = true; 1898 } 1899 1900 // We're going to complain about a bunch of spurious specifiers; 1901 // only do this if we're declaring a tag, because otherwise we 1902 // should be getting diag::ext_no_declarators. 1903 if (emittedWarning || (TagD && TagD->isInvalidDecl())) 1904 return TagD; 1905 1906 // Note that a linkage-specification sets a storage class, but 1907 // 'extern "C" struct foo;' is actually valid and not theoretically 1908 // useless. 1909 if (DeclSpec::SCS scs = DS.getStorageClassSpec()) 1910 if (!DS.isExternInLinkageSpec()) 1911 Diag(DS.getStorageClassSpecLoc(), diag::warn_standalone_specifier) 1912 << DeclSpec::getSpecifierName(scs); 1913 1914 if (DS.isThreadSpecified()) 1915 Diag(DS.getThreadSpecLoc(), diag::warn_standalone_specifier) << "__thread"; 1916 if (DS.getTypeQualifiers()) { 1917 if (DS.getTypeQualifiers() & DeclSpec::TQ_const) 1918 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "const"; 1919 if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile) 1920 Diag(DS.getConstSpecLoc(), diag::warn_standalone_specifier) << "volatile"; 1921 // Restrict is covered above. 1922 } 1923 if (DS.isInlineSpecified()) 1924 Diag(DS.getInlineSpecLoc(), diag::warn_standalone_specifier) << "inline"; 1925 if (DS.isVirtualSpecified()) 1926 Diag(DS.getVirtualSpecLoc(), diag::warn_standalone_specifier) << "virtual"; 1927 if (DS.isExplicitSpecified()) 1928 Diag(DS.getExplicitSpecLoc(), diag::warn_standalone_specifier) <<"explicit"; 1929 1930 // FIXME: Warn on useless attributes 1931 1932 return TagD; 1933} 1934 1935/// ActOnVlaStmt - This rouine if finds a vla expression in a decl spec. 1936/// builds a statement for it and returns it so it is evaluated. 1937StmtResult Sema::ActOnVlaStmt(const DeclSpec &DS) { 1938 StmtResult R; 1939 if (DS.getTypeSpecType() == DeclSpec::TST_typeofExpr) { 1940 Expr *Exp = DS.getRepAsExpr(); 1941 QualType Ty = Exp->getType(); 1942 if (Ty->isPointerType()) { 1943 do 1944 Ty = Ty->getAs<PointerType>()->getPointeeType(); 1945 while (Ty->isPointerType()); 1946 } 1947 if (Ty->isVariableArrayType()) { 1948 R = ActOnExprStmt(MakeFullExpr(Exp)); 1949 } 1950 } 1951 return R; 1952} 1953 1954/// We are trying to inject an anonymous member into the given scope; 1955/// check if there's an existing declaration that can't be overloaded. 1956/// 1957/// \return true if this is a forbidden redeclaration 1958static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1959 Scope *S, 1960 DeclContext *Owner, 1961 DeclarationName Name, 1962 SourceLocation NameLoc, 1963 unsigned diagnostic) { 1964 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1965 Sema::ForRedeclaration); 1966 if (!SemaRef.LookupName(R, S)) return false; 1967 1968 if (R.getAsSingle<TagDecl>()) 1969 return false; 1970 1971 // Pick a representative declaration. 1972 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1973 assert(PrevDecl && "Expected a non-null Decl"); 1974 1975 if (!SemaRef.isDeclInScope(PrevDecl, Owner, S)) 1976 return false; 1977 1978 SemaRef.Diag(NameLoc, diagnostic) << Name; 1979 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1980 1981 return true; 1982} 1983 1984/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1985/// anonymous struct or union AnonRecord into the owning context Owner 1986/// and scope S. This routine will be invoked just after we realize 1987/// that an unnamed union or struct is actually an anonymous union or 1988/// struct, e.g., 1989/// 1990/// @code 1991/// union { 1992/// int i; 1993/// float f; 1994/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1995/// // f into the surrounding scope.x 1996/// @endcode 1997/// 1998/// This routine is recursive, injecting the names of nested anonymous 1999/// structs/unions into the owning context and scope as well. 2000static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 2001 DeclContext *Owner, 2002 RecordDecl *AnonRecord, 2003 AccessSpecifier AS, 2004 llvm::SmallVector<NamedDecl*, 2> &Chaining, 2005 bool MSAnonStruct) { 2006 unsigned diagKind 2007 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 2008 : diag::err_anonymous_struct_member_redecl; 2009 2010 bool Invalid = false; 2011 2012 // Look every FieldDecl and IndirectFieldDecl with a name. 2013 for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(), 2014 DEnd = AnonRecord->decls_end(); 2015 D != DEnd; ++D) { 2016 if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) && 2017 cast<NamedDecl>(*D)->getDeclName()) { 2018 ValueDecl *VD = cast<ValueDecl>(*D); 2019 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(), 2020 VD->getLocation(), diagKind)) { 2021 // C++ [class.union]p2: 2022 // The names of the members of an anonymous union shall be 2023 // distinct from the names of any other entity in the 2024 // scope in which the anonymous union is declared. 2025 Invalid = true; 2026 } else { 2027 // C++ [class.union]p2: 2028 // For the purpose of name lookup, after the anonymous union 2029 // definition, the members of the anonymous union are 2030 // considered to have been defined in the scope in which the 2031 // anonymous union is declared. 2032 unsigned OldChainingSize = Chaining.size(); 2033 if (IndirectFieldDecl *IF = dyn_cast<IndirectFieldDecl>(VD)) 2034 for (IndirectFieldDecl::chain_iterator PI = IF->chain_begin(), 2035 PE = IF->chain_end(); PI != PE; ++PI) 2036 Chaining.push_back(*PI); 2037 else 2038 Chaining.push_back(VD); 2039 2040 assert(Chaining.size() >= 2); 2041 NamedDecl **NamedChain = 2042 new (SemaRef.Context)NamedDecl*[Chaining.size()]; 2043 for (unsigned i = 0; i < Chaining.size(); i++) 2044 NamedChain[i] = Chaining[i]; 2045 2046 IndirectFieldDecl* IndirectField = 2047 IndirectFieldDecl::Create(SemaRef.Context, Owner, VD->getLocation(), 2048 VD->getIdentifier(), VD->getType(), 2049 NamedChain, Chaining.size()); 2050 2051 IndirectField->setAccess(AS); 2052 IndirectField->setImplicit(); 2053 SemaRef.PushOnScopeChains(IndirectField, S); 2054 2055 // That includes picking up the appropriate access specifier. 2056 if (AS != AS_none) IndirectField->setAccess(AS); 2057 2058 Chaining.resize(OldChainingSize); 2059 } 2060 } 2061 } 2062 2063 return Invalid; 2064} 2065 2066/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 2067/// a VarDecl::StorageClass. Any error reporting is up to the caller: 2068/// illegal input values are mapped to SC_None. 2069static StorageClass 2070StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2071 switch (StorageClassSpec) { 2072 case DeclSpec::SCS_unspecified: return SC_None; 2073 case DeclSpec::SCS_extern: return SC_Extern; 2074 case DeclSpec::SCS_static: return SC_Static; 2075 case DeclSpec::SCS_auto: return SC_Auto; 2076 case DeclSpec::SCS_register: return SC_Register; 2077 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2078 // Illegal SCSs map to None: error reporting is up to the caller. 2079 case DeclSpec::SCS_mutable: // Fall through. 2080 case DeclSpec::SCS_typedef: return SC_None; 2081 } 2082 llvm_unreachable("unknown storage class specifier"); 2083} 2084 2085/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 2086/// a StorageClass. Any error reporting is up to the caller: 2087/// illegal input values are mapped to SC_None. 2088static StorageClass 2089StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec) { 2090 switch (StorageClassSpec) { 2091 case DeclSpec::SCS_unspecified: return SC_None; 2092 case DeclSpec::SCS_extern: return SC_Extern; 2093 case DeclSpec::SCS_static: return SC_Static; 2094 case DeclSpec::SCS_private_extern: return SC_PrivateExtern; 2095 // Illegal SCSs map to None: error reporting is up to the caller. 2096 case DeclSpec::SCS_auto: // Fall through. 2097 case DeclSpec::SCS_mutable: // Fall through. 2098 case DeclSpec::SCS_register: // Fall through. 2099 case DeclSpec::SCS_typedef: return SC_None; 2100 } 2101 llvm_unreachable("unknown storage class specifier"); 2102} 2103 2104/// BuildAnonymousStructOrUnion - Handle the declaration of an 2105/// anonymous structure or union. Anonymous unions are a C++ feature 2106/// (C++ [class.union]) and a GNU C extension; anonymous structures 2107/// are a GNU C and GNU C++ extension. 2108Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 2109 AccessSpecifier AS, 2110 RecordDecl *Record) { 2111 DeclContext *Owner = Record->getDeclContext(); 2112 2113 // Diagnose whether this anonymous struct/union is an extension. 2114 if (Record->isUnion() && !getLangOptions().CPlusPlus) 2115 Diag(Record->getLocation(), diag::ext_anonymous_union); 2116 else if (!Record->isUnion()) 2117 Diag(Record->getLocation(), diag::ext_anonymous_struct); 2118 2119 // C and C++ require different kinds of checks for anonymous 2120 // structs/unions. 2121 bool Invalid = false; 2122 if (getLangOptions().CPlusPlus) { 2123 const char* PrevSpec = 0; 2124 unsigned DiagID; 2125 // C++ [class.union]p3: 2126 // Anonymous unions declared in a named namespace or in the 2127 // global namespace shall be declared static. 2128 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 2129 (isa<TranslationUnitDecl>(Owner) || 2130 (isa<NamespaceDecl>(Owner) && 2131 cast<NamespaceDecl>(Owner)->getDeclName()))) { 2132 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 2133 Invalid = true; 2134 2135 // Recover by adding 'static'. 2136 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 2137 PrevSpec, DiagID, getLangOptions()); 2138 } 2139 // C++ [class.union]p3: 2140 // A storage class is not allowed in a declaration of an 2141 // anonymous union in a class scope. 2142 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 2143 isa<RecordDecl>(Owner)) { 2144 Diag(DS.getStorageClassSpecLoc(), 2145 diag::err_anonymous_union_with_storage_spec); 2146 Invalid = true; 2147 2148 // Recover by removing the storage specifier. 2149 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 2150 PrevSpec, DiagID, getLangOptions()); 2151 } 2152 2153 // C++ [class.union]p2: 2154 // The member-specification of an anonymous union shall only 2155 // define non-static data members. [Note: nested types and 2156 // functions cannot be declared within an anonymous union. ] 2157 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 2158 MemEnd = Record->decls_end(); 2159 Mem != MemEnd; ++Mem) { 2160 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 2161 // C++ [class.union]p3: 2162 // An anonymous union shall not have private or protected 2163 // members (clause 11). 2164 assert(FD->getAccess() != AS_none); 2165 if (FD->getAccess() != AS_public) { 2166 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 2167 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 2168 Invalid = true; 2169 } 2170 2171 if (CheckNontrivialField(FD)) 2172 Invalid = true; 2173 } else if ((*Mem)->isImplicit()) { 2174 // Any implicit members are fine. 2175 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 2176 // This is a type that showed up in an 2177 // elaborated-type-specifier inside the anonymous struct or 2178 // union, but which actually declares a type outside of the 2179 // anonymous struct or union. It's okay. 2180 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 2181 if (!MemRecord->isAnonymousStructOrUnion() && 2182 MemRecord->getDeclName()) { 2183 // Visual C++ allows type definition in anonymous struct or union. 2184 if (getLangOptions().Microsoft) 2185 Diag(MemRecord->getLocation(), diag::ext_anonymous_record_with_type) 2186 << (int)Record->isUnion(); 2187 else { 2188 // This is a nested type declaration. 2189 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 2190 << (int)Record->isUnion(); 2191 Invalid = true; 2192 } 2193 } 2194 } else if (isa<AccessSpecDecl>(*Mem)) { 2195 // Any access specifier is fine. 2196 } else { 2197 // We have something that isn't a non-static data 2198 // member. Complain about it. 2199 unsigned DK = diag::err_anonymous_record_bad_member; 2200 if (isa<TypeDecl>(*Mem)) 2201 DK = diag::err_anonymous_record_with_type; 2202 else if (isa<FunctionDecl>(*Mem)) 2203 DK = diag::err_anonymous_record_with_function; 2204 else if (isa<VarDecl>(*Mem)) 2205 DK = diag::err_anonymous_record_with_static; 2206 2207 // Visual C++ allows type definition in anonymous struct or union. 2208 if (getLangOptions().Microsoft && 2209 DK == diag::err_anonymous_record_with_type) 2210 Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type) 2211 << (int)Record->isUnion(); 2212 else { 2213 Diag((*Mem)->getLocation(), DK) 2214 << (int)Record->isUnion(); 2215 Invalid = true; 2216 } 2217 } 2218 } 2219 } 2220 2221 if (!Record->isUnion() && !Owner->isRecord()) { 2222 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 2223 << (int)getLangOptions().CPlusPlus; 2224 Invalid = true; 2225 } 2226 2227 // Mock up a declarator. 2228 Declarator Dc(DS, Declarator::TypeNameContext); 2229 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2230 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 2231 2232 // Create a declaration for this anonymous struct/union. 2233 NamedDecl *Anon = 0; 2234 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 2235 Anon = FieldDecl::Create(Context, OwningClass, 2236 DS.getSourceRange().getBegin(), 2237 Record->getLocation(), 2238 /*IdentifierInfo=*/0, 2239 Context.getTypeDeclType(Record), 2240 TInfo, 2241 /*BitWidth=*/0, /*Mutable=*/false); 2242 Anon->setAccess(AS); 2243 if (getLangOptions().CPlusPlus) 2244 FieldCollector->Add(cast<FieldDecl>(Anon)); 2245 } else { 2246 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 2247 assert(SCSpec != DeclSpec::SCS_typedef && 2248 "Parser allowed 'typedef' as storage class VarDecl."); 2249 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 2250 if (SCSpec == DeclSpec::SCS_mutable) { 2251 // mutable can only appear on non-static class members, so it's always 2252 // an error here 2253 Diag(Record->getLocation(), diag::err_mutable_nonmember); 2254 Invalid = true; 2255 SC = SC_None; 2256 } 2257 SCSpec = DS.getStorageClassSpecAsWritten(); 2258 VarDecl::StorageClass SCAsWritten 2259 = StorageClassSpecToVarDeclStorageClass(SCSpec); 2260 2261 Anon = VarDecl::Create(Context, Owner, 2262 DS.getSourceRange().getBegin(), 2263 Record->getLocation(), /*IdentifierInfo=*/0, 2264 Context.getTypeDeclType(Record), 2265 TInfo, SC, SCAsWritten); 2266 } 2267 Anon->setImplicit(); 2268 2269 // Add the anonymous struct/union object to the current 2270 // context. We'll be referencing this object when we refer to one of 2271 // its members. 2272 Owner->addDecl(Anon); 2273 2274 // Inject the members of the anonymous struct/union into the owning 2275 // context and into the identifier resolver chain for name lookup 2276 // purposes. 2277 llvm::SmallVector<NamedDecl*, 2> Chain; 2278 Chain.push_back(Anon); 2279 2280 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS, 2281 Chain, false)) 2282 Invalid = true; 2283 2284 // Mark this as an anonymous struct/union type. Note that we do not 2285 // do this until after we have already checked and injected the 2286 // members of this anonymous struct/union type, because otherwise 2287 // the members could be injected twice: once by DeclContext when it 2288 // builds its lookup table, and once by 2289 // InjectAnonymousStructOrUnionMembers. 2290 Record->setAnonymousStructOrUnion(true); 2291 2292 if (Invalid) 2293 Anon->setInvalidDecl(); 2294 2295 return Anon; 2296} 2297 2298/// BuildMicrosoftCAnonymousStruct - Handle the declaration of an 2299/// Microsoft C anonymous structure. 2300/// Ref: http://msdn.microsoft.com/en-us/library/z2cx9y4f.aspx 2301/// Example: 2302/// 2303/// struct A { int a; }; 2304/// struct B { struct A; int b; }; 2305/// 2306/// void foo() { 2307/// B var; 2308/// var.a = 3; 2309/// } 2310/// 2311Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS, 2312 RecordDecl *Record) { 2313 2314 // If there is no Record, get the record via the typedef. 2315 if (!Record) 2316 Record = DS.getRepAsType().get()->getAsStructureType()->getDecl(); 2317 2318 // Mock up a declarator. 2319 Declarator Dc(DS, Declarator::TypeNameContext); 2320 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 2321 assert(TInfo && "couldn't build declarator info for anonymous struct"); 2322 2323 // Create a declaration for this anonymous struct. 2324 NamedDecl* Anon = FieldDecl::Create(Context, 2325 cast<RecordDecl>(CurContext), 2326 DS.getSourceRange().getBegin(), 2327 DS.getSourceRange().getBegin(), 2328 /*IdentifierInfo=*/0, 2329 Context.getTypeDeclType(Record), 2330 TInfo, 2331 /*BitWidth=*/0, /*Mutable=*/false); 2332 Anon->setImplicit(); 2333 2334 // Add the anonymous struct object to the current context. 2335 CurContext->addDecl(Anon); 2336 2337 // Inject the members of the anonymous struct into the current 2338 // context and into the identifier resolver chain for name lookup 2339 // purposes. 2340 llvm::SmallVector<NamedDecl*, 2> Chain; 2341 Chain.push_back(Anon); 2342 2343 if (InjectAnonymousStructOrUnionMembers(*this, S, CurContext, 2344 Record->getDefinition(), 2345 AS_none, Chain, true)) 2346 Anon->setInvalidDecl(); 2347 2348 return Anon; 2349} 2350 2351/// GetNameForDeclarator - Determine the full declaration name for the 2352/// given Declarator. 2353DeclarationNameInfo Sema::GetNameForDeclarator(Declarator &D) { 2354 return GetNameFromUnqualifiedId(D.getName()); 2355} 2356 2357/// \brief Retrieves the declaration name from a parsed unqualified-id. 2358DeclarationNameInfo 2359Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 2360 DeclarationNameInfo NameInfo; 2361 NameInfo.setLoc(Name.StartLocation); 2362 2363 switch (Name.getKind()) { 2364 2365 case UnqualifiedId::IK_Identifier: 2366 NameInfo.setName(Name.Identifier); 2367 NameInfo.setLoc(Name.StartLocation); 2368 return NameInfo; 2369 2370 case UnqualifiedId::IK_OperatorFunctionId: 2371 NameInfo.setName(Context.DeclarationNames.getCXXOperatorName( 2372 Name.OperatorFunctionId.Operator)); 2373 NameInfo.setLoc(Name.StartLocation); 2374 NameInfo.getInfo().CXXOperatorName.BeginOpNameLoc 2375 = Name.OperatorFunctionId.SymbolLocations[0]; 2376 NameInfo.getInfo().CXXOperatorName.EndOpNameLoc 2377 = Name.EndLocation.getRawEncoding(); 2378 return NameInfo; 2379 2380 case UnqualifiedId::IK_LiteralOperatorId: 2381 NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName( 2382 Name.Identifier)); 2383 NameInfo.setLoc(Name.StartLocation); 2384 NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation); 2385 return NameInfo; 2386 2387 case UnqualifiedId::IK_ConversionFunctionId: { 2388 TypeSourceInfo *TInfo; 2389 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo); 2390 if (Ty.isNull()) 2391 return DeclarationNameInfo(); 2392 NameInfo.setName(Context.DeclarationNames.getCXXConversionFunctionName( 2393 Context.getCanonicalType(Ty))); 2394 NameInfo.setLoc(Name.StartLocation); 2395 NameInfo.setNamedTypeInfo(TInfo); 2396 return NameInfo; 2397 } 2398 2399 case UnqualifiedId::IK_ConstructorName: { 2400 TypeSourceInfo *TInfo; 2401 QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo); 2402 if (Ty.isNull()) 2403 return DeclarationNameInfo(); 2404 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2405 Context.getCanonicalType(Ty))); 2406 NameInfo.setLoc(Name.StartLocation); 2407 NameInfo.setNamedTypeInfo(TInfo); 2408 return NameInfo; 2409 } 2410 2411 case UnqualifiedId::IK_ConstructorTemplateId: { 2412 // In well-formed code, we can only have a constructor 2413 // template-id that refers to the current context, so go there 2414 // to find the actual type being constructed. 2415 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 2416 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 2417 return DeclarationNameInfo(); 2418 2419 // Determine the type of the class being constructed. 2420 QualType CurClassType = Context.getTypeDeclType(CurClass); 2421 2422 // FIXME: Check two things: that the template-id names the same type as 2423 // CurClassType, and that the template-id does not occur when the name 2424 // was qualified. 2425 2426 NameInfo.setName(Context.DeclarationNames.getCXXConstructorName( 2427 Context.getCanonicalType(CurClassType))); 2428 NameInfo.setLoc(Name.StartLocation); 2429 // FIXME: should we retrieve TypeSourceInfo? 2430 NameInfo.setNamedTypeInfo(0); 2431 return NameInfo; 2432 } 2433 2434 case UnqualifiedId::IK_DestructorName: { 2435 TypeSourceInfo *TInfo; 2436 QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo); 2437 if (Ty.isNull()) 2438 return DeclarationNameInfo(); 2439 NameInfo.setName(Context.DeclarationNames.getCXXDestructorName( 2440 Context.getCanonicalType(Ty))); 2441 NameInfo.setLoc(Name.StartLocation); 2442 NameInfo.setNamedTypeInfo(TInfo); 2443 return NameInfo; 2444 } 2445 2446 case UnqualifiedId::IK_TemplateId: { 2447 TemplateName TName = Name.TemplateId->Template.get(); 2448 SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc; 2449 return Context.getNameForTemplate(TName, TNameLoc); 2450 } 2451 2452 } // switch (Name.getKind()) 2453 2454 assert(false && "Unknown name kind"); 2455 return DeclarationNameInfo(); 2456} 2457 2458/// isNearlyMatchingFunction - Determine whether the C++ functions 2459/// Declaration and Definition are "nearly" matching. This heuristic 2460/// is used to improve diagnostics in the case where an out-of-line 2461/// function definition doesn't match any declaration within 2462/// the class or namespace. 2463static bool isNearlyMatchingFunction(ASTContext &Context, 2464 FunctionDecl *Declaration, 2465 FunctionDecl *Definition) { 2466 if (Declaration->param_size() != Definition->param_size()) 2467 return false; 2468 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 2469 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 2470 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 2471 2472 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 2473 DefParamTy.getNonReferenceType())) 2474 return false; 2475 } 2476 2477 return true; 2478} 2479 2480/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 2481/// declarator needs to be rebuilt in the current instantiation. 2482/// Any bits of declarator which appear before the name are valid for 2483/// consideration here. That's specifically the type in the decl spec 2484/// and the base type in any member-pointer chunks. 2485static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2486 DeclarationName Name) { 2487 // The types we specifically need to rebuild are: 2488 // - typenames, typeofs, and decltypes 2489 // - types which will become injected class names 2490 // Of course, we also need to rebuild any type referencing such a 2491 // type. It's safest to just say "dependent", but we call out a 2492 // few cases here. 2493 2494 DeclSpec &DS = D.getMutableDeclSpec(); 2495 switch (DS.getTypeSpecType()) { 2496 case DeclSpec::TST_typename: 2497 case DeclSpec::TST_typeofType: 2498 case DeclSpec::TST_decltype: { 2499 // Grab the type from the parser. 2500 TypeSourceInfo *TSI = 0; 2501 QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI); 2502 if (T.isNull() || !T->isDependentType()) break; 2503 2504 // Make sure there's a type source info. This isn't really much 2505 // of a waste; most dependent types should have type source info 2506 // attached already. 2507 if (!TSI) 2508 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2509 2510 // Rebuild the type in the current instantiation. 2511 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2512 if (!TSI) return true; 2513 2514 // Store the new type back in the decl spec. 2515 ParsedType LocType = S.CreateParsedType(TSI->getType(), TSI); 2516 DS.UpdateTypeRep(LocType); 2517 break; 2518 } 2519 2520 case DeclSpec::TST_typeofExpr: { 2521 Expr *E = DS.getRepAsExpr(); 2522 ExprResult Result = S.RebuildExprInCurrentInstantiation(E); 2523 if (Result.isInvalid()) return true; 2524 DS.UpdateExprRep(Result.get()); 2525 break; 2526 } 2527 2528 default: 2529 // Nothing to do for these decl specs. 2530 break; 2531 } 2532 2533 // It doesn't matter what order we do this in. 2534 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2535 DeclaratorChunk &Chunk = D.getTypeObject(I); 2536 2537 // The only type information in the declarator which can come 2538 // before the declaration name is the base type of a member 2539 // pointer. 2540 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2541 continue; 2542 2543 // Rebuild the scope specifier in-place. 2544 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2545 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2546 return true; 2547 } 2548 2549 return false; 2550} 2551 2552Decl *Sema::ActOnDeclarator(Scope *S, Declarator &D) { 2553 return HandleDeclarator(S, D, MultiTemplateParamsArg(*this), false); 2554} 2555 2556Decl *Sema::HandleDeclarator(Scope *S, Declarator &D, 2557 MultiTemplateParamsArg TemplateParamLists, 2558 bool IsFunctionDefinition) { 2559 // TODO: consider using NameInfo for diagnostic. 2560 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 2561 DeclarationName Name = NameInfo.getName(); 2562 2563 // All of these full declarators require an identifier. If it doesn't have 2564 // one, the ParsedFreeStandingDeclSpec action should be used. 2565 if (!Name) { 2566 if (!D.isInvalidType()) // Reject this if we think it is valid. 2567 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2568 diag::err_declarator_need_ident) 2569 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2570 return 0; 2571 } else if (DiagnoseUnexpandedParameterPack(NameInfo, UPPC_DeclarationType)) 2572 return 0; 2573 2574 // The scope passed in may not be a decl scope. Zip up the scope tree until 2575 // we find one that is. 2576 while ((S->getFlags() & Scope::DeclScope) == 0 || 2577 (S->getFlags() & Scope::TemplateParamScope) != 0) 2578 S = S->getParent(); 2579 2580 DeclContext *DC = CurContext; 2581 if (D.getCXXScopeSpec().isInvalid()) 2582 D.setInvalidType(); 2583 else if (D.getCXXScopeSpec().isSet()) { 2584 if (DiagnoseUnexpandedParameterPack(D.getCXXScopeSpec(), 2585 UPPC_DeclarationQualifier)) 2586 return 0; 2587 2588 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2589 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2590 if (!DC) { 2591 // If we could not compute the declaration context, it's because the 2592 // declaration context is dependent but does not refer to a class, 2593 // class template, or class template partial specialization. Complain 2594 // and return early, to avoid the coming semantic disaster. 2595 Diag(D.getIdentifierLoc(), 2596 diag::err_template_qualified_declarator_no_match) 2597 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2598 << D.getCXXScopeSpec().getRange(); 2599 return 0; 2600 } 2601 2602 bool IsDependentContext = DC->isDependentContext(); 2603 2604 if (!IsDependentContext && 2605 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2606 return 0; 2607 2608 if (isa<CXXRecordDecl>(DC)) { 2609 if (!cast<CXXRecordDecl>(DC)->hasDefinition()) { 2610 Diag(D.getIdentifierLoc(), 2611 diag::err_member_def_undefined_record) 2612 << Name << DC << D.getCXXScopeSpec().getRange(); 2613 D.setInvalidType(); 2614 } else if (isa<CXXRecordDecl>(CurContext) && 2615 !D.getDeclSpec().isFriendSpecified()) { 2616 // The user provided a superfluous scope specifier inside a class 2617 // definition: 2618 // 2619 // class X { 2620 // void X::f(); 2621 // }; 2622 if (CurContext->Equals(DC)) 2623 Diag(D.getIdentifierLoc(), diag::warn_member_extra_qualification) 2624 << Name << FixItHint::CreateRemoval(D.getCXXScopeSpec().getRange()); 2625 else 2626 Diag(D.getIdentifierLoc(), diag::err_member_qualification) 2627 << Name << D.getCXXScopeSpec().getRange(); 2628 2629 // Pretend that this qualifier was not here. 2630 D.getCXXScopeSpec().clear(); 2631 } 2632 } 2633 2634 // Check whether we need to rebuild the type of the given 2635 // declaration in the current instantiation. 2636 if (EnteringContext && IsDependentContext && 2637 TemplateParamLists.size() != 0) { 2638 ContextRAII SavedContext(*this, DC); 2639 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2640 D.setInvalidType(); 2641 } 2642 } 2643 2644 // C++ [class.mem]p13: 2645 // If T is the name of a class, then each of the following shall have a 2646 // name different from T: 2647 // - every static data member of class T; 2648 // - every member function of class T 2649 // - every member of class T that is itself a type; 2650 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) 2651 if (Record->getIdentifier() && Record->getDeclName() == Name) { 2652 Diag(D.getIdentifierLoc(), diag::err_member_name_of_class) 2653 << Name; 2654 2655 // If this is a typedef, we'll end up spewing multiple diagnostics. 2656 // Just return early; it's safer. 2657 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2658 return 0; 2659 } 2660 2661 NamedDecl *New; 2662 2663 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2664 QualType R = TInfo->getType(); 2665 2666 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 2667 UPPC_DeclarationType)) 2668 D.setInvalidType(); 2669 2670 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, 2671 ForRedeclaration); 2672 2673 // See if this is a redefinition of a variable in the same scope. 2674 if (!D.getCXXScopeSpec().isSet()) { 2675 bool IsLinkageLookup = false; 2676 2677 // If the declaration we're planning to build will be a function 2678 // or object with linkage, then look for another declaration with 2679 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2680 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2681 /* Do nothing*/; 2682 else if (R->isFunctionType()) { 2683 if (CurContext->isFunctionOrMethod() || 2684 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2685 IsLinkageLookup = true; 2686 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2687 IsLinkageLookup = true; 2688 else if (CurContext->getRedeclContext()->isTranslationUnit() && 2689 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2690 IsLinkageLookup = true; 2691 2692 if (IsLinkageLookup) 2693 Previous.clear(LookupRedeclarationWithLinkage); 2694 2695 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2696 } else { // Something like "int foo::x;" 2697 LookupQualifiedName(Previous, DC); 2698 2699 // Don't consider using declarations as previous declarations for 2700 // out-of-line members. 2701 RemoveUsingDecls(Previous); 2702 2703 // C++ 7.3.1.2p2: 2704 // Members (including explicit specializations of templates) of a named 2705 // namespace can also be defined outside that namespace by explicit 2706 // qualification of the name being defined, provided that the entity being 2707 // defined was already declared in the namespace and the definition appears 2708 // after the point of declaration in a namespace that encloses the 2709 // declarations namespace. 2710 // 2711 // Note that we only check the context at this point. We don't yet 2712 // have enough information to make sure that PrevDecl is actually 2713 // the declaration we want to match. For example, given: 2714 // 2715 // class X { 2716 // void f(); 2717 // void f(float); 2718 // }; 2719 // 2720 // void X::f(int) { } // ill-formed 2721 // 2722 // In this case, PrevDecl will point to the overload set 2723 // containing the two f's declared in X, but neither of them 2724 // matches. 2725 2726 // First check whether we named the global scope. 2727 if (isa<TranslationUnitDecl>(DC)) { 2728 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2729 << Name << D.getCXXScopeSpec().getRange(); 2730 } else { 2731 DeclContext *Cur = CurContext; 2732 while (isa<LinkageSpecDecl>(Cur)) 2733 Cur = Cur->getParent(); 2734 if (!Cur->Encloses(DC)) { 2735 // The qualifying scope doesn't enclose the original declaration. 2736 // Emit diagnostic based on current scope. 2737 SourceLocation L = D.getIdentifierLoc(); 2738 SourceRange R = D.getCXXScopeSpec().getRange(); 2739 if (isa<FunctionDecl>(Cur)) 2740 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2741 else 2742 Diag(L, diag::err_invalid_declarator_scope) 2743 << Name << cast<NamedDecl>(DC) << R; 2744 D.setInvalidType(); 2745 } 2746 } 2747 } 2748 2749 if (Previous.isSingleResult() && 2750 Previous.getFoundDecl()->isTemplateParameter()) { 2751 // Maybe we will complain about the shadowed template parameter. 2752 if (!D.isInvalidType()) 2753 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2754 Previous.getFoundDecl())) 2755 D.setInvalidType(); 2756 2757 // Just pretend that we didn't see the previous declaration. 2758 Previous.clear(); 2759 } 2760 2761 // In C++, the previous declaration we find might be a tag type 2762 // (class or enum). In this case, the new declaration will hide the 2763 // tag type. Note that this does does not apply if we're declaring a 2764 // typedef (C++ [dcl.typedef]p4). 2765 if (Previous.isSingleTagDecl() && 2766 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2767 Previous.clear(); 2768 2769 bool Redeclaration = false; 2770 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2771 if (TemplateParamLists.size()) { 2772 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2773 return 0; 2774 } 2775 2776 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2777 } else if (R->isFunctionType()) { 2778 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2779 move(TemplateParamLists), 2780 IsFunctionDefinition, Redeclaration); 2781 } else { 2782 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2783 move(TemplateParamLists), 2784 Redeclaration); 2785 } 2786 2787 if (New == 0) 2788 return 0; 2789 2790 // If this has an identifier and is not an invalid redeclaration or 2791 // function template specialization, add it to the scope stack. 2792 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2793 PushOnScopeChains(New, S); 2794 2795 return New; 2796} 2797 2798/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2799/// types into constant array types in certain situations which would otherwise 2800/// be errors (for GCC compatibility). 2801static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2802 ASTContext &Context, 2803 bool &SizeIsNegative, 2804 llvm::APSInt &Oversized) { 2805 // This method tries to turn a variable array into a constant 2806 // array even when the size isn't an ICE. This is necessary 2807 // for compatibility with code that depends on gcc's buggy 2808 // constant expression folding, like struct {char x[(int)(char*)2];} 2809 SizeIsNegative = false; 2810 Oversized = 0; 2811 2812 if (T->isDependentType()) 2813 return QualType(); 2814 2815 QualifierCollector Qs; 2816 const Type *Ty = Qs.strip(T); 2817 2818 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2819 QualType Pointee = PTy->getPointeeType(); 2820 QualType FixedType = 2821 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative, 2822 Oversized); 2823 if (FixedType.isNull()) return FixedType; 2824 FixedType = Context.getPointerType(FixedType); 2825 return Qs.apply(Context, FixedType); 2826 } 2827 if (const ParenType* PTy = dyn_cast<ParenType>(Ty)) { 2828 QualType Inner = PTy->getInnerType(); 2829 QualType FixedType = 2830 TryToFixInvalidVariablyModifiedType(Inner, Context, SizeIsNegative, 2831 Oversized); 2832 if (FixedType.isNull()) return FixedType; 2833 FixedType = Context.getParenType(FixedType); 2834 return Qs.apply(Context, FixedType); 2835 } 2836 2837 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2838 if (!VLATy) 2839 return QualType(); 2840 // FIXME: We should probably handle this case 2841 if (VLATy->getElementType()->isVariablyModifiedType()) 2842 return QualType(); 2843 2844 Expr::EvalResult EvalResult; 2845 if (!VLATy->getSizeExpr() || 2846 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2847 !EvalResult.Val.isInt()) 2848 return QualType(); 2849 2850 // Check whether the array size is negative. 2851 llvm::APSInt &Res = EvalResult.Val.getInt(); 2852 if (Res.isSigned() && Res.isNegative()) { 2853 SizeIsNegative = true; 2854 return QualType(); 2855 } 2856 2857 // Check whether the array is too large to be addressed. 2858 unsigned ActiveSizeBits 2859 = ConstantArrayType::getNumAddressingBits(Context, VLATy->getElementType(), 2860 Res); 2861 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) { 2862 Oversized = Res; 2863 return QualType(); 2864 } 2865 2866 return Context.getConstantArrayType(VLATy->getElementType(), 2867 Res, ArrayType::Normal, 0); 2868} 2869 2870/// \brief Register the given locally-scoped external C declaration so 2871/// that it can be found later for redeclarations 2872void 2873Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2874 const LookupResult &Previous, 2875 Scope *S) { 2876 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2877 "Decl is not a locally-scoped decl!"); 2878 // Note that we have a locally-scoped external with this name. 2879 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2880 2881 if (!Previous.isSingleResult()) 2882 return; 2883 2884 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2885 2886 // If there was a previous declaration of this variable, it may be 2887 // in our identifier chain. Update the identifier chain with the new 2888 // declaration. 2889 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2890 // The previous declaration was found on the identifer resolver 2891 // chain, so remove it from its scope. 2892 while (S && !S->isDeclScope(PrevDecl)) 2893 S = S->getParent(); 2894 2895 if (S) 2896 S->RemoveDecl(PrevDecl); 2897 } 2898} 2899 2900/// \brief Diagnose function specifiers on a declaration of an identifier that 2901/// does not identify a function. 2902void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2903 // FIXME: We should probably indicate the identifier in question to avoid 2904 // confusion for constructs like "inline int a(), b;" 2905 if (D.getDeclSpec().isInlineSpecified()) 2906 Diag(D.getDeclSpec().getInlineSpecLoc(), 2907 diag::err_inline_non_function); 2908 2909 if (D.getDeclSpec().isVirtualSpecified()) 2910 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2911 diag::err_virtual_non_function); 2912 2913 if (D.getDeclSpec().isExplicitSpecified()) 2914 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2915 diag::err_explicit_non_function); 2916} 2917 2918NamedDecl* 2919Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2920 QualType R, TypeSourceInfo *TInfo, 2921 LookupResult &Previous, bool &Redeclaration) { 2922 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2923 if (D.getCXXScopeSpec().isSet()) { 2924 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2925 << D.getCXXScopeSpec().getRange(); 2926 D.setInvalidType(); 2927 // Pretend we didn't see the scope specifier. 2928 DC = CurContext; 2929 Previous.clear(); 2930 } 2931 2932 if (getLangOptions().CPlusPlus) { 2933 // Check that there are no default arguments (C++ only). 2934 CheckExtraCXXDefaultArguments(D); 2935 } 2936 2937 DiagnoseFunctionSpecifiers(D); 2938 2939 if (D.getDeclSpec().isThreadSpecified()) 2940 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2941 2942 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2943 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2944 << D.getName().getSourceRange(); 2945 return 0; 2946 } 2947 2948 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2949 if (!NewTD) return 0; 2950 2951 // Handle attributes prior to checking for duplicates in MergeVarDecl 2952 ProcessDeclAttributes(S, NewTD, D); 2953 2954 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2955 // then it shall have block scope. 2956 // Note that variably modified types must be fixed before merging the decl so 2957 // that redeclarations will match. 2958 QualType T = NewTD->getUnderlyingType(); 2959 if (T->isVariablyModifiedType()) { 2960 getCurFunction()->setHasBranchProtectedScope(); 2961 2962 if (S->getFnParent() == 0) { 2963 bool SizeIsNegative; 2964 llvm::APSInt Oversized; 2965 QualType FixedTy = 2966 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 2967 Oversized); 2968 if (!FixedTy.isNull()) { 2969 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2970 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2971 } else { 2972 if (SizeIsNegative) 2973 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2974 else if (T->isVariableArrayType()) 2975 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2976 else if (Oversized.getBoolValue()) 2977 Diag(D.getIdentifierLoc(), diag::err_array_too_large) 2978 << Oversized.toString(10); 2979 else 2980 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2981 NewTD->setInvalidDecl(); 2982 } 2983 } 2984 } 2985 2986 // Merge the decl with the existing one if appropriate. If the decl is 2987 // in an outer scope, it isn't the same thing. 2988 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false, 2989 /*ExplicitInstantiationOrSpecialization=*/false); 2990 if (!Previous.empty()) { 2991 Redeclaration = true; 2992 MergeTypeDefDecl(NewTD, Previous); 2993 } 2994 2995 // If this is the C FILE type, notify the AST context. 2996 if (IdentifierInfo *II = NewTD->getIdentifier()) 2997 if (!NewTD->isInvalidDecl() && 2998 NewTD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 2999 if (II->isStr("FILE")) 3000 Context.setFILEDecl(NewTD); 3001 else if (II->isStr("jmp_buf")) 3002 Context.setjmp_bufDecl(NewTD); 3003 else if (II->isStr("sigjmp_buf")) 3004 Context.setsigjmp_bufDecl(NewTD); 3005 else if (II->isStr("__builtin_va_list")) 3006 Context.setBuiltinVaListType(Context.getTypedefType(NewTD)); 3007 } 3008 3009 return NewTD; 3010} 3011 3012/// \brief Determines whether the given declaration is an out-of-scope 3013/// previous declaration. 3014/// 3015/// This routine should be invoked when name lookup has found a 3016/// previous declaration (PrevDecl) that is not in the scope where a 3017/// new declaration by the same name is being introduced. If the new 3018/// declaration occurs in a local scope, previous declarations with 3019/// linkage may still be considered previous declarations (C99 3020/// 6.2.2p4-5, C++ [basic.link]p6). 3021/// 3022/// \param PrevDecl the previous declaration found by name 3023/// lookup 3024/// 3025/// \param DC the context in which the new declaration is being 3026/// declared. 3027/// 3028/// \returns true if PrevDecl is an out-of-scope previous declaration 3029/// for a new delcaration with the same name. 3030static bool 3031isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 3032 ASTContext &Context) { 3033 if (!PrevDecl) 3034 return false; 3035 3036 if (!PrevDecl->hasLinkage()) 3037 return false; 3038 3039 if (Context.getLangOptions().CPlusPlus) { 3040 // C++ [basic.link]p6: 3041 // If there is a visible declaration of an entity with linkage 3042 // having the same name and type, ignoring entities declared 3043 // outside the innermost enclosing namespace scope, the block 3044 // scope declaration declares that same entity and receives the 3045 // linkage of the previous declaration. 3046 DeclContext *OuterContext = DC->getRedeclContext(); 3047 if (!OuterContext->isFunctionOrMethod()) 3048 // This rule only applies to block-scope declarations. 3049 return false; 3050 3051 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 3052 if (PrevOuterContext->isRecord()) 3053 // We found a member function: ignore it. 3054 return false; 3055 3056 // Find the innermost enclosing namespace for the new and 3057 // previous declarations. 3058 OuterContext = OuterContext->getEnclosingNamespaceContext(); 3059 PrevOuterContext = PrevOuterContext->getEnclosingNamespaceContext(); 3060 3061 // The previous declaration is in a different namespace, so it 3062 // isn't the same function. 3063 if (!OuterContext->Equals(PrevOuterContext)) 3064 return false; 3065 } 3066 3067 return true; 3068} 3069 3070static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 3071 CXXScopeSpec &SS = D.getCXXScopeSpec(); 3072 if (!SS.isSet()) return; 3073 DD->setQualifierInfo(SS.getWithLocInContext(DD->getASTContext())); 3074} 3075 3076NamedDecl* 3077Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC, 3078 QualType R, TypeSourceInfo *TInfo, 3079 LookupResult &Previous, 3080 MultiTemplateParamsArg TemplateParamLists, 3081 bool &Redeclaration) { 3082 DeclarationName Name = GetNameForDeclarator(D).getName(); 3083 3084 // Check that there are no default arguments (C++ only). 3085 if (getLangOptions().CPlusPlus) 3086 CheckExtraCXXDefaultArguments(D); 3087 3088 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 3089 assert(SCSpec != DeclSpec::SCS_typedef && 3090 "Parser allowed 'typedef' as storage class VarDecl."); 3091 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec); 3092 if (SCSpec == DeclSpec::SCS_mutable) { 3093 // mutable can only appear on non-static class members, so it's always 3094 // an error here 3095 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 3096 D.setInvalidType(); 3097 SC = SC_None; 3098 } 3099 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3100 VarDecl::StorageClass SCAsWritten 3101 = StorageClassSpecToVarDeclStorageClass(SCSpec); 3102 3103 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3104 if (!II) { 3105 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 3106 << Name.getAsString(); 3107 return 0; 3108 } 3109 3110 DiagnoseFunctionSpecifiers(D); 3111 3112 if (!DC->isRecord() && S->getFnParent() == 0) { 3113 // C99 6.9p2: The storage-class specifiers auto and register shall not 3114 // appear in the declaration specifiers in an external declaration. 3115 if (SC == SC_Auto || SC == SC_Register) { 3116 3117 // If this is a register variable with an asm label specified, then this 3118 // is a GNU extension. 3119 if (SC == SC_Register && D.getAsmLabel()) 3120 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 3121 else 3122 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 3123 D.setInvalidType(); 3124 } 3125 } 3126 3127 bool isExplicitSpecialization = false; 3128 VarDecl *NewVD; 3129 if (!getLangOptions().CPlusPlus) { 3130 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3131 D.getIdentifierLoc(), II, 3132 R, TInfo, SC, SCAsWritten); 3133 3134 if (D.isInvalidType()) 3135 NewVD->setInvalidDecl(); 3136 } else { 3137 if (DC->isRecord() && !CurContext->isRecord()) { 3138 // This is an out-of-line definition of a static data member. 3139 if (SC == SC_Static) { 3140 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3141 diag::err_static_out_of_line) 3142 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3143 } else if (SC == SC_None) 3144 SC = SC_Static; 3145 } 3146 if (SC == SC_Static) { 3147 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 3148 if (RD->isLocalClass()) 3149 Diag(D.getIdentifierLoc(), 3150 diag::err_static_data_member_not_allowed_in_local_class) 3151 << Name << RD->getDeclName(); 3152 3153 // C++ [class.union]p1: If a union contains a static data member, 3154 // the program is ill-formed. 3155 // 3156 // We also disallow static data members in anonymous structs. 3157 if (CurContext->isRecord() && (RD->isUnion() || !RD->getDeclName())) 3158 Diag(D.getIdentifierLoc(), 3159 diag::err_static_data_member_not_allowed_in_union_or_anon_struct) 3160 << Name << RD->isUnion(); 3161 } 3162 } 3163 3164 // Match up the template parameter lists with the scope specifier, then 3165 // determine whether we have a template or a template specialization. 3166 isExplicitSpecialization = false; 3167 bool Invalid = false; 3168 if (TemplateParameterList *TemplateParams 3169 = MatchTemplateParametersToScopeSpecifier( 3170 D.getDeclSpec().getSourceRange().getBegin(), 3171 D.getCXXScopeSpec(), 3172 TemplateParamLists.get(), 3173 TemplateParamLists.size(), 3174 /*never a friend*/ false, 3175 isExplicitSpecialization, 3176 Invalid)) { 3177 if (TemplateParams->size() > 0) { 3178 // There is no such thing as a variable template. 3179 Diag(D.getIdentifierLoc(), diag::err_template_variable) 3180 << II 3181 << SourceRange(TemplateParams->getTemplateLoc(), 3182 TemplateParams->getRAngleLoc()); 3183 return 0; 3184 } else { 3185 // There is an extraneous 'template<>' for this variable. Complain 3186 // about it, but allow the declaration of the variable. 3187 Diag(TemplateParams->getTemplateLoc(), 3188 diag::err_template_variable_noparams) 3189 << II 3190 << SourceRange(TemplateParams->getTemplateLoc(), 3191 TemplateParams->getRAngleLoc()); 3192 isExplicitSpecialization = true; 3193 } 3194 } 3195 3196 NewVD = VarDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3197 D.getIdentifierLoc(), II, 3198 R, TInfo, SC, SCAsWritten); 3199 3200 // If this decl has an auto type in need of deduction, make a note of the 3201 // Decl so we can diagnose uses of it in its own initializer. 3202 if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto && 3203 R->getContainedAutoType()) 3204 ParsingInitForAutoVars.insert(NewVD); 3205 3206 if (D.isInvalidType() || Invalid) 3207 NewVD->setInvalidDecl(); 3208 3209 SetNestedNameSpecifier(NewVD, D); 3210 3211 if (TemplateParamLists.size() > 0 && D.getCXXScopeSpec().isSet()) { 3212 NewVD->setTemplateParameterListsInfo(Context, 3213 TemplateParamLists.size(), 3214 TemplateParamLists.release()); 3215 } 3216 } 3217 3218 if (D.getDeclSpec().isThreadSpecified()) { 3219 if (NewVD->hasLocalStorage()) 3220 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 3221 else if (!Context.Target.isTLSSupported()) 3222 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 3223 else 3224 NewVD->setThreadSpecified(true); 3225 } 3226 3227 // Set the lexical context. If the declarator has a C++ scope specifier, the 3228 // lexical context will be different from the semantic context. 3229 NewVD->setLexicalDeclContext(CurContext); 3230 3231 // Handle attributes prior to checking for duplicates in MergeVarDecl 3232 ProcessDeclAttributes(S, NewVD, D); 3233 3234 // Handle GNU asm-label extension (encoded as an attribute). 3235 if (Expr *E = (Expr*)D.getAsmLabel()) { 3236 // The parser guarantees this is a string. 3237 StringLiteral *SE = cast<StringLiteral>(E); 3238 llvm::StringRef Label = SE->getString(); 3239 if (S->getFnParent() != 0) { 3240 switch (SC) { 3241 case SC_None: 3242 case SC_Auto: 3243 Diag(E->getExprLoc(), diag::warn_asm_label_on_auto_decl) << Label; 3244 break; 3245 case SC_Register: 3246 if (!Context.Target.isValidGCCRegisterName(Label)) 3247 Diag(E->getExprLoc(), diag::err_asm_unknown_register_name) << Label; 3248 break; 3249 case SC_Static: 3250 case SC_Extern: 3251 case SC_PrivateExtern: 3252 break; 3253 } 3254 } 3255 3256 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), 3257 Context, Label)); 3258 } 3259 3260 // Diagnose shadowed variables before filtering for scope. 3261 if (!D.getCXXScopeSpec().isSet()) 3262 CheckShadow(S, NewVD, Previous); 3263 3264 // Don't consider existing declarations that are in a different 3265 // scope and are out-of-semantic-context declarations (if the new 3266 // declaration has linkage). 3267 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage(), 3268 isExplicitSpecialization); 3269 3270 if (!getLangOptions().CPlusPlus) 3271 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3272 else { 3273 // Merge the decl with the existing one if appropriate. 3274 if (!Previous.empty()) { 3275 if (Previous.isSingleResult() && 3276 isa<FieldDecl>(Previous.getFoundDecl()) && 3277 D.getCXXScopeSpec().isSet()) { 3278 // The user tried to define a non-static data member 3279 // out-of-line (C++ [dcl.meaning]p1). 3280 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 3281 << D.getCXXScopeSpec().getRange(); 3282 Previous.clear(); 3283 NewVD->setInvalidDecl(); 3284 } 3285 } else if (D.getCXXScopeSpec().isSet()) { 3286 // No previous declaration in the qualifying scope. 3287 Diag(D.getIdentifierLoc(), diag::err_no_member) 3288 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 3289 << D.getCXXScopeSpec().getRange(); 3290 NewVD->setInvalidDecl(); 3291 } 3292 3293 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 3294 3295 // This is an explicit specialization of a static data member. Check it. 3296 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 3297 CheckMemberSpecialization(NewVD, Previous)) 3298 NewVD->setInvalidDecl(); 3299 } 3300 3301 // attributes declared post-definition are currently ignored 3302 // FIXME: This should be handled in attribute merging, not 3303 // here. 3304 if (Previous.isSingleResult()) { 3305 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 3306 if (Def && (Def = Def->getDefinition()) && 3307 Def != NewVD && D.hasAttributes()) { 3308 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 3309 Diag(Def->getLocation(), diag::note_previous_definition); 3310 } 3311 } 3312 3313 // If this is a locally-scoped extern C variable, update the map of 3314 // such variables. 3315 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 3316 !NewVD->isInvalidDecl()) 3317 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 3318 3319 // If there's a #pragma GCC visibility in scope, and this isn't a class 3320 // member, set the visibility of this variable. 3321 if (NewVD->getLinkage() == ExternalLinkage && !DC->isRecord()) 3322 AddPushedVisibilityAttribute(NewVD); 3323 3324 MarkUnusedFileScopedDecl(NewVD); 3325 3326 return NewVD; 3327} 3328 3329/// \brief Diagnose variable or built-in function shadowing. Implements 3330/// -Wshadow. 3331/// 3332/// This method is called whenever a VarDecl is added to a "useful" 3333/// scope. 3334/// 3335/// \param S the scope in which the shadowing name is being declared 3336/// \param R the lookup of the name 3337/// 3338void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 3339 // Return if warning is ignored. 3340 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, R.getNameLoc()) == 3341 Diagnostic::Ignored) 3342 return; 3343 3344 // Don't diagnose declarations at file scope. 3345 DeclContext *NewDC = D->getDeclContext(); 3346 if (NewDC->isFileContext()) 3347 return; 3348 3349 // Only diagnose if we're shadowing an unambiguous field or variable. 3350 if (R.getResultKind() != LookupResult::Found) 3351 return; 3352 3353 NamedDecl* ShadowedDecl = R.getFoundDecl(); 3354 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 3355 return; 3356 3357 // Fields are not shadowed by variables in C++ static methods. 3358 if (isa<FieldDecl>(ShadowedDecl)) 3359 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewDC)) 3360 if (MD->isStatic()) 3361 return; 3362 3363 if (VarDecl *shadowedVar = dyn_cast<VarDecl>(ShadowedDecl)) 3364 if (shadowedVar->isExternC()) { 3365 // Don't warn for this case: 3366 // 3367 // @code 3368 // extern int bob; 3369 // void f() { 3370 // extern int bob; 3371 // } 3372 // @endcode 3373 if (D->isExternC()) 3374 return; 3375 3376 // For shadowing external vars, make sure that we point to the global 3377 // declaration, not a locally scoped extern declaration. 3378 for (VarDecl::redecl_iterator 3379 I = shadowedVar->redecls_begin(), E = shadowedVar->redecls_end(); 3380 I != E; ++I) 3381 if (I->isFileVarDecl()) { 3382 ShadowedDecl = *I; 3383 break; 3384 } 3385 } 3386 3387 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 3388 3389 // Only warn about certain kinds of shadowing for class members. 3390 if (NewDC && NewDC->isRecord()) { 3391 // In particular, don't warn about shadowing non-class members. 3392 if (!OldDC->isRecord()) 3393 return; 3394 3395 // TODO: should we warn about static data members shadowing 3396 // static data members from base classes? 3397 3398 // TODO: don't diagnose for inaccessible shadowed members. 3399 // This is hard to do perfectly because we might friend the 3400 // shadowing context, but that's just a false negative. 3401 } 3402 3403 // Determine what kind of declaration we're shadowing. 3404 unsigned Kind; 3405 if (isa<RecordDecl>(OldDC)) { 3406 if (isa<FieldDecl>(ShadowedDecl)) 3407 Kind = 3; // field 3408 else 3409 Kind = 2; // static data member 3410 } else if (OldDC->isFileContext()) 3411 Kind = 1; // global 3412 else 3413 Kind = 0; // local 3414 3415 DeclarationName Name = R.getLookupName(); 3416 3417 // Emit warning and note. 3418 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 3419 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 3420} 3421 3422/// \brief Check -Wshadow without the advantage of a previous lookup. 3423void Sema::CheckShadow(Scope *S, VarDecl *D) { 3424 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow, D->getLocation()) == 3425 Diagnostic::Ignored) 3426 return; 3427 3428 LookupResult R(*this, D->getDeclName(), D->getLocation(), 3429 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3430 LookupName(R, S); 3431 CheckShadow(S, D, R); 3432} 3433 3434/// \brief Perform semantic checking on a newly-created variable 3435/// declaration. 3436/// 3437/// This routine performs all of the type-checking required for a 3438/// variable declaration once it has been built. It is used both to 3439/// check variables after they have been parsed and their declarators 3440/// have been translated into a declaration, and to check variables 3441/// that have been instantiated from a template. 3442/// 3443/// Sets NewVD->isInvalidDecl() if an error was encountered. 3444void Sema::CheckVariableDeclaration(VarDecl *NewVD, 3445 LookupResult &Previous, 3446 bool &Redeclaration) { 3447 // If the decl is already known invalid, don't check it. 3448 if (NewVD->isInvalidDecl()) 3449 return; 3450 3451 QualType T = NewVD->getType(); 3452 3453 if (T->isObjCObjectType()) { 3454 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 3455 return NewVD->setInvalidDecl(); 3456 } 3457 3458 // Emit an error if an address space was applied to decl with local storage. 3459 // This includes arrays of objects with address space qualifiers, but not 3460 // automatic variables that point to other address spaces. 3461 // ISO/IEC TR 18037 S5.1.2 3462 if (NewVD->hasLocalStorage() && T.getAddressSpace() != 0) { 3463 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 3464 return NewVD->setInvalidDecl(); 3465 } 3466 3467 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 3468 && !NewVD->hasAttr<BlocksAttr>()) 3469 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 3470 3471 bool isVM = T->isVariablyModifiedType(); 3472 if (isVM || NewVD->hasAttr<CleanupAttr>() || 3473 NewVD->hasAttr<BlocksAttr>()) 3474 getCurFunction()->setHasBranchProtectedScope(); 3475 3476 if ((isVM && NewVD->hasLinkage()) || 3477 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 3478 bool SizeIsNegative; 3479 llvm::APSInt Oversized; 3480 QualType FixedTy = 3481 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative, 3482 Oversized); 3483 3484 if (FixedTy.isNull() && T->isVariableArrayType()) { 3485 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 3486 // FIXME: This won't give the correct result for 3487 // int a[10][n]; 3488 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 3489 3490 if (NewVD->isFileVarDecl()) 3491 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 3492 << SizeRange; 3493 else if (NewVD->getStorageClass() == SC_Static) 3494 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 3495 << SizeRange; 3496 else 3497 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 3498 << SizeRange; 3499 return NewVD->setInvalidDecl(); 3500 } 3501 3502 if (FixedTy.isNull()) { 3503 if (NewVD->isFileVarDecl()) 3504 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 3505 else 3506 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 3507 return NewVD->setInvalidDecl(); 3508 } 3509 3510 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 3511 NewVD->setType(FixedTy); 3512 } 3513 3514 if (Previous.empty() && NewVD->isExternC()) { 3515 // Since we did not find anything by this name and we're declaring 3516 // an extern "C" variable, look for a non-visible extern "C" 3517 // declaration with the same name. 3518 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3519 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 3520 if (Pos != LocallyScopedExternalDecls.end()) 3521 Previous.addDecl(Pos->second); 3522 } 3523 3524 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 3525 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 3526 << T; 3527 return NewVD->setInvalidDecl(); 3528 } 3529 3530 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 3531 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 3532 return NewVD->setInvalidDecl(); 3533 } 3534 3535 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 3536 Diag(NewVD->getLocation(), diag::err_block_on_vm); 3537 return NewVD->setInvalidDecl(); 3538 } 3539 3540 // Function pointers and references cannot have qualified function type, only 3541 // function pointer-to-members can do that. 3542 QualType Pointee; 3543 unsigned PtrOrRef = 0; 3544 if (const PointerType *Ptr = T->getAs<PointerType>()) 3545 Pointee = Ptr->getPointeeType(); 3546 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 3547 Pointee = Ref->getPointeeType(); 3548 PtrOrRef = 1; 3549 } 3550 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 3551 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 3552 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 3553 << PtrOrRef; 3554 return NewVD->setInvalidDecl(); 3555 } 3556 3557 if (!Previous.empty()) { 3558 Redeclaration = true; 3559 MergeVarDecl(NewVD, Previous); 3560 } 3561} 3562 3563/// \brief Data used with FindOverriddenMethod 3564struct FindOverriddenMethodData { 3565 Sema *S; 3566 CXXMethodDecl *Method; 3567}; 3568 3569/// \brief Member lookup function that determines whether a given C++ 3570/// method overrides a method in a base class, to be used with 3571/// CXXRecordDecl::lookupInBases(). 3572static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 3573 CXXBasePath &Path, 3574 void *UserData) { 3575 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 3576 3577 FindOverriddenMethodData *Data 3578 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 3579 3580 DeclarationName Name = Data->Method->getDeclName(); 3581 3582 // FIXME: Do we care about other names here too? 3583 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3584 // We really want to find the base class destructor here. 3585 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 3586 CanQualType CT = Data->S->Context.getCanonicalType(T); 3587 3588 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 3589 } 3590 3591 for (Path.Decls = BaseRecord->lookup(Name); 3592 Path.Decls.first != Path.Decls.second; 3593 ++Path.Decls.first) { 3594 NamedDecl *D = *Path.Decls.first; 3595 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 3596 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 3597 return true; 3598 } 3599 } 3600 3601 return false; 3602} 3603 3604/// AddOverriddenMethods - See if a method overrides any in the base classes, 3605/// and if so, check that it's a valid override and remember it. 3606bool Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 3607 // Look for virtual methods in base classes that this method might override. 3608 CXXBasePaths Paths; 3609 FindOverriddenMethodData Data; 3610 Data.Method = MD; 3611 Data.S = this; 3612 bool AddedAny = false; 3613 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 3614 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 3615 E = Paths.found_decls_end(); I != E; ++I) { 3616 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 3617 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 3618 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 3619 !CheckIfOverriddenFunctionIsMarkedFinal(MD, OldMD)) { 3620 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 3621 AddedAny = true; 3622 } 3623 } 3624 } 3625 } 3626 3627 return AddedAny; 3628} 3629 3630static void DiagnoseInvalidRedeclaration(Sema &S, FunctionDecl *NewFD) { 3631 LookupResult Prev(S, NewFD->getDeclName(), NewFD->getLocation(), 3632 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 3633 S.LookupQualifiedName(Prev, NewFD->getDeclContext()); 3634 assert(!Prev.isAmbiguous() && 3635 "Cannot have an ambiguity in previous-declaration lookup"); 3636 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3637 Func != FuncEnd; ++Func) { 3638 if (isa<FunctionDecl>(*Func) && 3639 isNearlyMatchingFunction(S.Context, cast<FunctionDecl>(*Func), NewFD)) 3640 S.Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3641 } 3642} 3643 3644NamedDecl* 3645Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 3646 QualType R, TypeSourceInfo *TInfo, 3647 LookupResult &Previous, 3648 MultiTemplateParamsArg TemplateParamLists, 3649 bool IsFunctionDefinition, bool &Redeclaration) { 3650 assert(R.getTypePtr()->isFunctionType()); 3651 3652 // TODO: consider using NameInfo for diagnostic. 3653 DeclarationNameInfo NameInfo = GetNameForDeclarator(D); 3654 DeclarationName Name = NameInfo.getName(); 3655 FunctionDecl::StorageClass SC = SC_None; 3656 switch (D.getDeclSpec().getStorageClassSpec()) { 3657 default: assert(0 && "Unknown storage class!"); 3658 case DeclSpec::SCS_auto: 3659 case DeclSpec::SCS_register: 3660 case DeclSpec::SCS_mutable: 3661 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3662 diag::err_typecheck_sclass_func); 3663 D.setInvalidType(); 3664 break; 3665 case DeclSpec::SCS_unspecified: SC = SC_None; break; 3666 case DeclSpec::SCS_extern: SC = SC_Extern; break; 3667 case DeclSpec::SCS_static: { 3668 if (CurContext->getRedeclContext()->isFunctionOrMethod()) { 3669 // C99 6.7.1p5: 3670 // The declaration of an identifier for a function that has 3671 // block scope shall have no explicit storage-class specifier 3672 // other than extern 3673 // See also (C++ [dcl.stc]p4). 3674 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3675 diag::err_static_block_func); 3676 SC = SC_None; 3677 } else 3678 SC = SC_Static; 3679 break; 3680 } 3681 case DeclSpec::SCS_private_extern: SC = SC_PrivateExtern; break; 3682 } 3683 3684 if (D.getDeclSpec().isThreadSpecified()) 3685 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3686 3687 // Do not allow returning a objc interface by-value. 3688 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3689 Diag(D.getIdentifierLoc(), 3690 diag::err_object_cannot_be_passed_returned_by_value) << 0 3691 << R->getAs<FunctionType>()->getResultType(); 3692 D.setInvalidType(); 3693 } 3694 3695 FunctionDecl *NewFD; 3696 bool isInline = D.getDeclSpec().isInlineSpecified(); 3697 bool isFriend = false; 3698 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3699 FunctionDecl::StorageClass SCAsWritten 3700 = StorageClassSpecToFunctionDeclStorageClass(SCSpec); 3701 FunctionTemplateDecl *FunctionTemplate = 0; 3702 bool isExplicitSpecialization = false; 3703 bool isFunctionTemplateSpecialization = false; 3704 3705 if (!getLangOptions().CPlusPlus) { 3706 // Determine whether the function was written with a 3707 // prototype. This true when: 3708 // - there is a prototype in the declarator, or 3709 // - the type R of the function is some kind of typedef or other reference 3710 // to a type name (which eventually refers to a function type). 3711 bool HasPrototype = 3712 (D.isFunctionDeclarator() && D.getFunctionTypeInfo().hasPrototype) || 3713 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3714 3715 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3716 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3717 HasPrototype); 3718 if (D.isInvalidType()) 3719 NewFD->setInvalidDecl(); 3720 3721 // Set the lexical context. 3722 NewFD->setLexicalDeclContext(CurContext); 3723 // Filter out previous declarations that don't match the scope. 3724 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage(), 3725 /*ExplicitInstantiationOrSpecialization=*/false); 3726 } else { 3727 isFriend = D.getDeclSpec().isFriendSpecified(); 3728 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3729 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3730 bool isVirtualOkay = false; 3731 3732 // Check that the return type is not an abstract class type. 3733 // For record types, this is done by the AbstractClassUsageDiagnoser once 3734 // the class has been completely parsed. 3735 if (!DC->isRecord() && 3736 RequireNonAbstractType(D.getIdentifierLoc(), 3737 R->getAs<FunctionType>()->getResultType(), 3738 diag::err_abstract_type_in_decl, 3739 AbstractReturnType)) 3740 D.setInvalidType(); 3741 3742 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3743 // This is a C++ constructor declaration. 3744 assert(DC->isRecord() && 3745 "Constructors can only be declared in a member context"); 3746 3747 R = CheckConstructorDeclarator(D, R, SC); 3748 3749 // Create the new declaration 3750 NewFD = CXXConstructorDecl::Create(Context, 3751 cast<CXXRecordDecl>(DC), 3752 D.getSourceRange().getBegin(), 3753 NameInfo, R, TInfo, 3754 isExplicit, isInline, 3755 /*isImplicitlyDeclared=*/false); 3756 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3757 // This is a C++ destructor declaration. 3758 if (DC->isRecord()) { 3759 R = CheckDestructorDeclarator(D, R, SC); 3760 3761 NewFD = CXXDestructorDecl::Create(Context, 3762 cast<CXXRecordDecl>(DC), 3763 D.getSourceRange().getBegin(), 3764 NameInfo, R, TInfo, 3765 isInline, 3766 /*isImplicitlyDeclared=*/false); 3767 isVirtualOkay = true; 3768 } else { 3769 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3770 3771 // Create a FunctionDecl to satisfy the function definition parsing 3772 // code path. 3773 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3774 D.getIdentifierLoc(), Name, R, TInfo, 3775 SC, SCAsWritten, isInline, 3776 /*hasPrototype=*/true); 3777 D.setInvalidType(); 3778 } 3779 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3780 if (!DC->isRecord()) { 3781 Diag(D.getIdentifierLoc(), 3782 diag::err_conv_function_not_member); 3783 return 0; 3784 } 3785 3786 CheckConversionDeclarator(D, R, SC); 3787 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3788 D.getSourceRange().getBegin(), 3789 NameInfo, R, TInfo, 3790 isInline, isExplicit, 3791 SourceLocation()); 3792 3793 isVirtualOkay = true; 3794 } else if (DC->isRecord()) { 3795 // If the of the function is the same as the name of the record, then this 3796 // must be an invalid constructor that has a return type. 3797 // (The parser checks for a return type and makes the declarator a 3798 // constructor if it has no return type). 3799 // must have an invalid constructor that has a return type 3800 if (Name.getAsIdentifierInfo() && 3801 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3802 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3803 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3804 << SourceRange(D.getIdentifierLoc()); 3805 return 0; 3806 } 3807 3808 bool isStatic = SC == SC_Static; 3809 3810 // [class.free]p1: 3811 // Any allocation function for a class T is a static member 3812 // (even if not explicitly declared static). 3813 if (Name.getCXXOverloadedOperator() == OO_New || 3814 Name.getCXXOverloadedOperator() == OO_Array_New) 3815 isStatic = true; 3816 3817 // [class.free]p6 Any deallocation function for a class X is a static member 3818 // (even if not explicitly declared static). 3819 if (Name.getCXXOverloadedOperator() == OO_Delete || 3820 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3821 isStatic = true; 3822 3823 // This is a C++ method declaration. 3824 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3825 D.getSourceRange().getBegin(), 3826 NameInfo, R, TInfo, 3827 isStatic, SCAsWritten, isInline, 3828 SourceLocation()); 3829 3830 isVirtualOkay = !isStatic; 3831 } else { 3832 // Determine whether the function was written with a 3833 // prototype. This true when: 3834 // - we're in C++ (where every function has a prototype), 3835 NewFD = FunctionDecl::Create(Context, DC, D.getSourceRange().getBegin(), 3836 NameInfo, R, TInfo, SC, SCAsWritten, isInline, 3837 true/*HasPrototype*/); 3838 } 3839 3840 if (isFriend && !isInline && IsFunctionDefinition) { 3841 // C++ [class.friend]p5 3842 // A function can be defined in a friend declaration of a 3843 // class . . . . Such a function is implicitly inline. 3844 NewFD->setImplicitlyInline(); 3845 } 3846 3847 SetNestedNameSpecifier(NewFD, D); 3848 isExplicitSpecialization = false; 3849 isFunctionTemplateSpecialization = false; 3850 if (D.isInvalidType()) 3851 NewFD->setInvalidDecl(); 3852 3853 // Set the lexical context. If the declarator has a C++ 3854 // scope specifier, or is the object of a friend declaration, the 3855 // lexical context will be different from the semantic context. 3856 NewFD->setLexicalDeclContext(CurContext); 3857 3858 // Match up the template parameter lists with the scope specifier, then 3859 // determine whether we have a template or a template specialization. 3860 bool Invalid = false; 3861 if (TemplateParameterList *TemplateParams 3862 = MatchTemplateParametersToScopeSpecifier( 3863 D.getDeclSpec().getSourceRange().getBegin(), 3864 D.getCXXScopeSpec(), 3865 TemplateParamLists.get(), 3866 TemplateParamLists.size(), 3867 isFriend, 3868 isExplicitSpecialization, 3869 Invalid)) { 3870 if (TemplateParams->size() > 0) { 3871 // This is a function template 3872 3873 // Check that we can declare a template here. 3874 if (CheckTemplateDeclScope(S, TemplateParams)) 3875 return 0; 3876 3877 // A destructor cannot be a template. 3878 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3879 Diag(NewFD->getLocation(), diag::err_destructor_template); 3880 return 0; 3881 } 3882 3883 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3884 NewFD->getLocation(), 3885 Name, TemplateParams, 3886 NewFD); 3887 FunctionTemplate->setLexicalDeclContext(CurContext); 3888 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3889 3890 // For source fidelity, store the other template param lists. 3891 if (TemplateParamLists.size() > 1) { 3892 NewFD->setTemplateParameterListsInfo(Context, 3893 TemplateParamLists.size() - 1, 3894 TemplateParamLists.release()); 3895 } 3896 } else { 3897 // This is a function template specialization. 3898 isFunctionTemplateSpecialization = true; 3899 // For source fidelity, store all the template param lists. 3900 NewFD->setTemplateParameterListsInfo(Context, 3901 TemplateParamLists.size(), 3902 TemplateParamLists.release()); 3903 3904 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3905 if (isFriend) { 3906 // We want to remove the "template<>", found here. 3907 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3908 3909 // If we remove the template<> and the name is not a 3910 // template-id, we're actually silently creating a problem: 3911 // the friend declaration will refer to an untemplated decl, 3912 // and clearly the user wants a template specialization. So 3913 // we need to insert '<>' after the name. 3914 SourceLocation InsertLoc; 3915 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3916 InsertLoc = D.getName().getSourceRange().getEnd(); 3917 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3918 } 3919 3920 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3921 << Name << RemoveRange 3922 << FixItHint::CreateRemoval(RemoveRange) 3923 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3924 } 3925 } 3926 } 3927 else { 3928 // All template param lists were matched against the scope specifier: 3929 // this is NOT (an explicit specialization of) a template. 3930 if (TemplateParamLists.size() > 0) 3931 // For source fidelity, store all the template param lists. 3932 NewFD->setTemplateParameterListsInfo(Context, 3933 TemplateParamLists.size(), 3934 TemplateParamLists.release()); 3935 } 3936 3937 if (Invalid) { 3938 NewFD->setInvalidDecl(); 3939 if (FunctionTemplate) 3940 FunctionTemplate->setInvalidDecl(); 3941 } 3942 3943 // C++ [dcl.fct.spec]p5: 3944 // The virtual specifier shall only be used in declarations of 3945 // nonstatic class member functions that appear within a 3946 // member-specification of a class declaration; see 10.3. 3947 // 3948 if (isVirtual && !NewFD->isInvalidDecl()) { 3949 if (!isVirtualOkay) { 3950 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3951 diag::err_virtual_non_function); 3952 } else if (!CurContext->isRecord()) { 3953 // 'virtual' was specified outside of the class. 3954 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3955 diag::err_virtual_out_of_class) 3956 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3957 } else if (NewFD->getDescribedFunctionTemplate()) { 3958 // C++ [temp.mem]p3: 3959 // A member function template shall not be virtual. 3960 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3961 diag::err_virtual_member_function_template) 3962 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3963 } else { 3964 // Okay: Add virtual to the method. 3965 NewFD->setVirtualAsWritten(true); 3966 } 3967 } 3968 3969 // C++ [dcl.fct.spec]p3: 3970 // The inline specifier shall not appear on a block scope function declaration. 3971 if (isInline && !NewFD->isInvalidDecl()) { 3972 if (CurContext->isFunctionOrMethod()) { 3973 // 'inline' is not allowed on block scope function declaration. 3974 Diag(D.getDeclSpec().getInlineSpecLoc(), 3975 diag::err_inline_declaration_block_scope) << Name 3976 << FixItHint::CreateRemoval(D.getDeclSpec().getInlineSpecLoc()); 3977 } 3978 } 3979 3980 // C++ [dcl.fct.spec]p6: 3981 // The explicit specifier shall be used only in the declaration of a 3982 // constructor or conversion function within its class definition; see 12.3.1 3983 // and 12.3.2. 3984 if (isExplicit && !NewFD->isInvalidDecl()) { 3985 if (!CurContext->isRecord()) { 3986 // 'explicit' was specified outside of the class. 3987 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3988 diag::err_explicit_out_of_class) 3989 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3990 } else if (!isa<CXXConstructorDecl>(NewFD) && 3991 !isa<CXXConversionDecl>(NewFD)) { 3992 // 'explicit' was specified on a function that wasn't a constructor 3993 // or conversion function. 3994 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3995 diag::err_explicit_non_ctor_or_conv_function) 3996 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3997 } 3998 } 3999 4000 // Filter out previous declarations that don't match the scope. 4001 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage(), 4002 isExplicitSpecialization || 4003 isFunctionTemplateSpecialization); 4004 4005 if (isFriend) { 4006 // For now, claim that the objects have no previous declaration. 4007 if (FunctionTemplate) { 4008 FunctionTemplate->setObjectOfFriendDecl(false); 4009 FunctionTemplate->setAccess(AS_public); 4010 } 4011 NewFD->setObjectOfFriendDecl(false); 4012 NewFD->setAccess(AS_public); 4013 } 4014 4015 if (isa<CXXMethodDecl>(NewFD) && DC == CurContext && IsFunctionDefinition) { 4016 // A method is implicitly inline if it's defined in its class 4017 // definition. 4018 NewFD->setImplicitlyInline(); 4019 } 4020 4021 if (SC == SC_Static && isa<CXXMethodDecl>(NewFD) && 4022 !CurContext->isRecord()) { 4023 // C++ [class.static]p1: 4024 // A data or function member of a class may be declared static 4025 // in a class definition, in which case it is a static member of 4026 // the class. 4027 4028 // Complain about the 'static' specifier if it's on an out-of-line 4029 // member function definition. 4030 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 4031 diag::err_static_out_of_line) 4032 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 4033 } 4034 } 4035 4036 // Handle GNU asm-label extension (encoded as an attribute). 4037 if (Expr *E = (Expr*) D.getAsmLabel()) { 4038 // The parser guarantees this is a string. 4039 StringLiteral *SE = cast<StringLiteral>(E); 4040 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getStrTokenLoc(0), Context, 4041 SE->getString())); 4042 } 4043 4044 // Copy the parameter declarations from the declarator D to the function 4045 // declaration NewFD, if they are available. First scavenge them into Params. 4046 llvm::SmallVector<ParmVarDecl*, 16> Params; 4047 if (D.isFunctionDeclarator()) { 4048 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 4049 4050 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 4051 // function that takes no arguments, not a function that takes a 4052 // single void argument. 4053 // We let through "const void" here because Sema::GetTypeForDeclarator 4054 // already checks for that case. 4055 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 4056 FTI.ArgInfo[0].Param && 4057 cast<ParmVarDecl>(FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 4058 // Empty arg list, don't push any params. 4059 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[0].Param); 4060 4061 // In C++, the empty parameter-type-list must be spelled "void"; a 4062 // typedef of void is not permitted. 4063 if (getLangOptions().CPlusPlus && 4064 Param->getType().getUnqualifiedType() != Context.VoidTy) 4065 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 4066 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 4067 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 4068 ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param); 4069 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 4070 Param->setDeclContext(NewFD); 4071 Params.push_back(Param); 4072 4073 if (Param->isInvalidDecl()) 4074 NewFD->setInvalidDecl(); 4075 } 4076 } 4077 4078 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 4079 // When we're declaring a function with a typedef, typeof, etc as in the 4080 // following example, we'll need to synthesize (unnamed) 4081 // parameters for use in the declaration. 4082 // 4083 // @code 4084 // typedef void fn(int); 4085 // fn f; 4086 // @endcode 4087 4088 // Synthesize a parameter for each argument type. 4089 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 4090 AE = FT->arg_type_end(); AI != AE; ++AI) { 4091 ParmVarDecl *Param = 4092 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 4093 Params.push_back(Param); 4094 } 4095 } else { 4096 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 4097 "Should not need args for typedef of non-prototype fn"); 4098 } 4099 // Finally, we know we have the right number of parameters, install them. 4100 NewFD->setParams(Params.data(), Params.size()); 4101 4102 // Process the non-inheritable attributes on this declaration. 4103 ProcessDeclAttributes(S, NewFD, D, 4104 /*NonInheritable=*/true, /*Inheritable=*/false); 4105 4106 if (!getLangOptions().CPlusPlus) { 4107 // Perform semantic checking on the function declaration. 4108 bool isExplctSpecialization=false; 4109 CheckFunctionDeclaration(S, NewFD, Previous, isExplctSpecialization, 4110 Redeclaration); 4111 assert((NewFD->isInvalidDecl() || !Redeclaration || 4112 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4113 "previous declaration set still overloaded"); 4114 } else { 4115 // If the declarator is a template-id, translate the parser's template 4116 // argument list into our AST format. 4117 bool HasExplicitTemplateArgs = false; 4118 TemplateArgumentListInfo TemplateArgs; 4119 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 4120 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 4121 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 4122 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 4123 ASTTemplateArgsPtr TemplateArgsPtr(*this, 4124 TemplateId->getTemplateArgs(), 4125 TemplateId->NumArgs); 4126 translateTemplateArguments(TemplateArgsPtr, 4127 TemplateArgs); 4128 TemplateArgsPtr.release(); 4129 4130 HasExplicitTemplateArgs = true; 4131 4132 if (FunctionTemplate) { 4133 // Function template with explicit template arguments. 4134 Diag(D.getIdentifierLoc(), diag::err_function_template_partial_spec) 4135 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc); 4136 4137 HasExplicitTemplateArgs = false; 4138 } else if (!isFunctionTemplateSpecialization && 4139 !D.getDeclSpec().isFriendSpecified()) { 4140 // We have encountered something that the user meant to be a 4141 // specialization (because it has explicitly-specified template 4142 // arguments) but that was not introduced with a "template<>" (or had 4143 // too few of them). 4144 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 4145 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 4146 << FixItHint::CreateInsertion( 4147 D.getDeclSpec().getSourceRange().getBegin(), 4148 "template<> "); 4149 isFunctionTemplateSpecialization = true; 4150 } else { 4151 // "friend void foo<>(int);" is an implicit specialization decl. 4152 isFunctionTemplateSpecialization = true; 4153 } 4154 } else if (isFriend && isFunctionTemplateSpecialization) { 4155 // This combination is only possible in a recovery case; the user 4156 // wrote something like: 4157 // template <> friend void foo(int); 4158 // which we're recovering from as if the user had written: 4159 // friend void foo<>(int); 4160 // Go ahead and fake up a template id. 4161 HasExplicitTemplateArgs = true; 4162 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 4163 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 4164 } 4165 4166 // If it's a friend (and only if it's a friend), it's possible 4167 // that either the specialized function type or the specialized 4168 // template is dependent, and therefore matching will fail. In 4169 // this case, don't check the specialization yet. 4170 if (isFunctionTemplateSpecialization && isFriend && 4171 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 4172 assert(HasExplicitTemplateArgs && 4173 "friend function specialization without template args"); 4174 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 4175 Previous)) 4176 NewFD->setInvalidDecl(); 4177 } else if (isFunctionTemplateSpecialization) { 4178 if (CurContext->isDependentContext() && CurContext->isRecord() 4179 && !isFriend) { 4180 Diag(NewFD->getLocation(), diag::err_function_specialization_in_class) 4181 << NewFD->getDeclName(); 4182 NewFD->setInvalidDecl(); 4183 return 0; 4184 } else if (CheckFunctionTemplateSpecialization(NewFD, 4185 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 4186 Previous)) 4187 NewFD->setInvalidDecl(); 4188 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 4189 if (CheckMemberSpecialization(NewFD, Previous)) 4190 NewFD->setInvalidDecl(); 4191 } 4192 4193 // Perform semantic checking on the function declaration. 4194 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 4195 Redeclaration); 4196 4197 assert((NewFD->isInvalidDecl() || !Redeclaration || 4198 Previous.getResultKind() != LookupResult::FoundOverloaded) && 4199 "previous declaration set still overloaded"); 4200 4201 NamedDecl *PrincipalDecl = (FunctionTemplate 4202 ? cast<NamedDecl>(FunctionTemplate) 4203 : NewFD); 4204 4205 if (isFriend && Redeclaration) { 4206 AccessSpecifier Access = AS_public; 4207 if (!NewFD->isInvalidDecl()) 4208 Access = NewFD->getPreviousDeclaration()->getAccess(); 4209 4210 NewFD->setAccess(Access); 4211 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 4212 4213 PrincipalDecl->setObjectOfFriendDecl(true); 4214 } 4215 4216 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 4217 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 4218 PrincipalDecl->setNonMemberOperator(); 4219 4220 // If we have a function template, check the template parameter 4221 // list. This will check and merge default template arguments. 4222 if (FunctionTemplate) { 4223 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 4224 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 4225 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 4226 D.getDeclSpec().isFriendSpecified() 4227 ? (IsFunctionDefinition 4228 ? TPC_FriendFunctionTemplateDefinition 4229 : TPC_FriendFunctionTemplate) 4230 : (D.getCXXScopeSpec().isSet() && 4231 DC && DC->isRecord() && 4232 DC->isDependentContext()) 4233 ? TPC_ClassTemplateMember 4234 : TPC_FunctionTemplate); 4235 } 4236 4237 if (NewFD->isInvalidDecl()) { 4238 // Ignore all the rest of this. 4239 } else if (!Redeclaration) { 4240 // Fake up an access specifier if it's supposed to be a class member. 4241 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 4242 NewFD->setAccess(AS_public); 4243 4244 // Qualified decls generally require a previous declaration. 4245 if (D.getCXXScopeSpec().isSet()) { 4246 // ...with the major exception of templated-scope or 4247 // dependent-scope friend declarations. 4248 4249 // TODO: we currently also suppress this check in dependent 4250 // contexts because (1) the parameter depth will be off when 4251 // matching friend templates and (2) we might actually be 4252 // selecting a friend based on a dependent factor. But there 4253 // are situations where these conditions don't apply and we 4254 // can actually do this check immediately. 4255 if (isFriend && 4256 (TemplateParamLists.size() || 4257 D.getCXXScopeSpec().getScopeRep()->isDependent() || 4258 CurContext->isDependentContext())) { 4259 // ignore these 4260 } else { 4261 // The user tried to provide an out-of-line definition for a 4262 // function that is a member of a class or namespace, but there 4263 // was no such member function declared (C++ [class.mfct]p2, 4264 // C++ [namespace.memdef]p2). For example: 4265 // 4266 // class X { 4267 // void f() const; 4268 // }; 4269 // 4270 // void X::f() { } // ill-formed 4271 // 4272 // Complain about this problem, and attempt to suggest close 4273 // matches (e.g., those that differ only in cv-qualifiers and 4274 // whether the parameter types are references). 4275 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 4276 << Name << DC << D.getCXXScopeSpec().getRange(); 4277 NewFD->setInvalidDecl(); 4278 4279 DiagnoseInvalidRedeclaration(*this, NewFD); 4280 } 4281 4282 // Unqualified local friend declarations are required to resolve 4283 // to something. 4284 } else if (isFriend && cast<CXXRecordDecl>(CurContext)->isLocalClass()) { 4285 Diag(D.getIdentifierLoc(), diag::err_no_matching_local_friend); 4286 NewFD->setInvalidDecl(); 4287 DiagnoseInvalidRedeclaration(*this, NewFD); 4288 } 4289 4290 } else if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 4291 !isFriend && !isFunctionTemplateSpecialization && 4292 !isExplicitSpecialization) { 4293 // An out-of-line member function declaration must also be a 4294 // definition (C++ [dcl.meaning]p1). 4295 // Note that this is not the case for explicit specializations of 4296 // function templates or member functions of class templates, per 4297 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 4298 // for compatibility with old SWIG code which likes to generate them. 4299 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 4300 << D.getCXXScopeSpec().getRange(); 4301 } 4302 } 4303 4304 4305 // Handle attributes. We need to have merged decls when handling attributes 4306 // (for example to check for conflicts, etc). 4307 // FIXME: This needs to happen before we merge declarations. Then, 4308 // let attribute merging cope with attribute conflicts. 4309 ProcessDeclAttributes(S, NewFD, D, 4310 /*NonInheritable=*/false, /*Inheritable=*/true); 4311 4312 // attributes declared post-definition are currently ignored 4313 // FIXME: This should happen during attribute merging 4314 if (Redeclaration && Previous.isSingleResult()) { 4315 const FunctionDecl *Def; 4316 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 4317 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 4318 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 4319 Diag(Def->getLocation(), diag::note_previous_definition); 4320 } 4321 } 4322 4323 AddKnownFunctionAttributes(NewFD); 4324 4325 if (NewFD->hasAttr<OverloadableAttr>() && 4326 !NewFD->getType()->getAs<FunctionProtoType>()) { 4327 Diag(NewFD->getLocation(), 4328 diag::err_attribute_overloadable_no_prototype) 4329 << NewFD; 4330 4331 // Turn this into a variadic function with no parameters. 4332 const FunctionType *FT = NewFD->getType()->getAs<FunctionType>(); 4333 FunctionProtoType::ExtProtoInfo EPI; 4334 EPI.Variadic = true; 4335 EPI.ExtInfo = FT->getExtInfo(); 4336 4337 QualType R = Context.getFunctionType(FT->getResultType(), 0, 0, EPI); 4338 NewFD->setType(R); 4339 } 4340 4341 // If there's a #pragma GCC visibility in scope, and this isn't a class 4342 // member, set the visibility of this function. 4343 if (NewFD->getLinkage() == ExternalLinkage && !DC->isRecord()) 4344 AddPushedVisibilityAttribute(NewFD); 4345 4346 // If this is a locally-scoped extern C function, update the 4347 // map of such names. 4348 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 4349 && !NewFD->isInvalidDecl()) 4350 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 4351 4352 // Set this FunctionDecl's range up to the right paren. 4353 NewFD->setRangeEnd(D.getSourceRange().getEnd()); 4354 4355 if (getLangOptions().CPlusPlus) { 4356 if (FunctionTemplate) { 4357 if (NewFD->isInvalidDecl()) 4358 FunctionTemplate->setInvalidDecl(); 4359 return FunctionTemplate; 4360 } 4361 } 4362 4363 MarkUnusedFileScopedDecl(NewFD); 4364 4365 if (getLangOptions().CUDA) 4366 if (IdentifierInfo *II = NewFD->getIdentifier()) 4367 if (!NewFD->isInvalidDecl() && 4368 NewFD->getDeclContext()->getRedeclContext()->isTranslationUnit()) { 4369 if (II->isStr("cudaConfigureCall")) { 4370 if (!R->getAs<FunctionType>()->getResultType()->isScalarType()) 4371 Diag(NewFD->getLocation(), diag::err_config_scalar_return); 4372 4373 Context.setcudaConfigureCallDecl(NewFD); 4374 } 4375 } 4376 4377 return NewFD; 4378} 4379 4380/// \brief Perform semantic checking of a new function declaration. 4381/// 4382/// Performs semantic analysis of the new function declaration 4383/// NewFD. This routine performs all semantic checking that does not 4384/// require the actual declarator involved in the declaration, and is 4385/// used both for the declaration of functions as they are parsed 4386/// (called via ActOnDeclarator) and for the declaration of functions 4387/// that have been instantiated via C++ template instantiation (called 4388/// via InstantiateDecl). 4389/// 4390/// \param IsExplicitSpecialiation whether this new function declaration is 4391/// an explicit specialization of the previous declaration. 4392/// 4393/// This sets NewFD->isInvalidDecl() to true if there was an error. 4394void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 4395 LookupResult &Previous, 4396 bool IsExplicitSpecialization, 4397 bool &Redeclaration) { 4398 // If NewFD is already known erroneous, don't do any of this checking. 4399 if (NewFD->isInvalidDecl()) { 4400 // If this is a class member, mark the class invalid immediately. 4401 // This avoids some consistency errors later. 4402 if (isa<CXXMethodDecl>(NewFD)) 4403 cast<CXXMethodDecl>(NewFD)->getParent()->setInvalidDecl(); 4404 4405 return; 4406 } 4407 4408 if (NewFD->getResultType()->isVariablyModifiedType()) { 4409 // Functions returning a variably modified type violate C99 6.7.5.2p2 4410 // because all functions have linkage. 4411 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 4412 return NewFD->setInvalidDecl(); 4413 } 4414 4415 if (NewFD->isMain()) 4416 CheckMain(NewFD); 4417 4418 // Check for a previous declaration of this name. 4419 if (Previous.empty() && NewFD->isExternC()) { 4420 // Since we did not find anything by this name and we're declaring 4421 // an extern "C" function, look for a non-visible extern "C" 4422 // declaration with the same name. 4423 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4424 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 4425 if (Pos != LocallyScopedExternalDecls.end()) 4426 Previous.addDecl(Pos->second); 4427 } 4428 4429 // Merge or overload the declaration with an existing declaration of 4430 // the same name, if appropriate. 4431 if (!Previous.empty()) { 4432 // Determine whether NewFD is an overload of PrevDecl or 4433 // a declaration that requires merging. If it's an overload, 4434 // there's no more work to do here; we'll just add the new 4435 // function to the scope. 4436 4437 NamedDecl *OldDecl = 0; 4438 if (!AllowOverloadingOfFunction(Previous, Context)) { 4439 Redeclaration = true; 4440 OldDecl = Previous.getFoundDecl(); 4441 } else { 4442 switch (CheckOverload(S, NewFD, Previous, OldDecl, 4443 /*NewIsUsingDecl*/ false)) { 4444 case Ovl_Match: 4445 Redeclaration = true; 4446 break; 4447 4448 case Ovl_NonFunction: 4449 Redeclaration = true; 4450 break; 4451 4452 case Ovl_Overload: 4453 Redeclaration = false; 4454 break; 4455 } 4456 4457 if (!getLangOptions().CPlusPlus && !NewFD->hasAttr<OverloadableAttr>()) { 4458 // If a function name is overloadable in C, then every function 4459 // with that name must be marked "overloadable". 4460 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 4461 << Redeclaration << NewFD; 4462 NamedDecl *OverloadedDecl = 0; 4463 if (Redeclaration) 4464 OverloadedDecl = OldDecl; 4465 else if (!Previous.empty()) 4466 OverloadedDecl = Previous.getRepresentativeDecl(); 4467 if (OverloadedDecl) 4468 Diag(OverloadedDecl->getLocation(), 4469 diag::note_attribute_overloadable_prev_overload); 4470 NewFD->addAttr(::new (Context) OverloadableAttr(SourceLocation(), 4471 Context)); 4472 } 4473 } 4474 4475 if (Redeclaration) { 4476 // NewFD and OldDecl represent declarations that need to be 4477 // merged. 4478 if (MergeFunctionDecl(NewFD, OldDecl)) 4479 return NewFD->setInvalidDecl(); 4480 4481 Previous.clear(); 4482 Previous.addDecl(OldDecl); 4483 4484 if (FunctionTemplateDecl *OldTemplateDecl 4485 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 4486 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 4487 FunctionTemplateDecl *NewTemplateDecl 4488 = NewFD->getDescribedFunctionTemplate(); 4489 assert(NewTemplateDecl && "Template/non-template mismatch"); 4490 if (CXXMethodDecl *Method 4491 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 4492 Method->setAccess(OldTemplateDecl->getAccess()); 4493 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 4494 } 4495 4496 // If this is an explicit specialization of a member that is a function 4497 // template, mark it as a member specialization. 4498 if (IsExplicitSpecialization && 4499 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 4500 NewTemplateDecl->setMemberSpecialization(); 4501 assert(OldTemplateDecl->isMemberSpecialization()); 4502 } 4503 } else { 4504 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 4505 NewFD->setAccess(OldDecl->getAccess()); 4506 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 4507 } 4508 } 4509 } 4510 4511 // Semantic checking for this function declaration (in isolation). 4512 if (getLangOptions().CPlusPlus) { 4513 // C++-specific checks. 4514 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 4515 CheckConstructor(Constructor); 4516 } else if (CXXDestructorDecl *Destructor = 4517 dyn_cast<CXXDestructorDecl>(NewFD)) { 4518 CXXRecordDecl *Record = Destructor->getParent(); 4519 QualType ClassType = Context.getTypeDeclType(Record); 4520 4521 // FIXME: Shouldn't we be able to perform this check even when the class 4522 // type is dependent? Both gcc and edg can handle that. 4523 if (!ClassType->isDependentType()) { 4524 DeclarationName Name 4525 = Context.DeclarationNames.getCXXDestructorName( 4526 Context.getCanonicalType(ClassType)); 4527 if (NewFD->getDeclName() != Name) { 4528 Diag(NewFD->getLocation(), diag::err_destructor_name); 4529 return NewFD->setInvalidDecl(); 4530 } 4531 } 4532 } else if (CXXConversionDecl *Conversion 4533 = dyn_cast<CXXConversionDecl>(NewFD)) { 4534 ActOnConversionDeclarator(Conversion); 4535 } 4536 4537 // Find any virtual functions that this function overrides. 4538 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 4539 if (!Method->isFunctionTemplateSpecialization() && 4540 !Method->getDescribedFunctionTemplate()) { 4541 if (AddOverriddenMethods(Method->getParent(), Method)) { 4542 // If the function was marked as "static", we have a problem. 4543 if (NewFD->getStorageClass() == SC_Static) { 4544 Diag(NewFD->getLocation(), diag::err_static_overrides_virtual) 4545 << NewFD->getDeclName(); 4546 for (CXXMethodDecl::method_iterator 4547 Overridden = Method->begin_overridden_methods(), 4548 OverriddenEnd = Method->end_overridden_methods(); 4549 Overridden != OverriddenEnd; 4550 ++Overridden) { 4551 Diag((*Overridden)->getLocation(), 4552 diag::note_overridden_virtual_function); 4553 } 4554 } 4555 } 4556 } 4557 } 4558 4559 // Extra checking for C++ overloaded operators (C++ [over.oper]). 4560 if (NewFD->isOverloadedOperator() && 4561 CheckOverloadedOperatorDeclaration(NewFD)) 4562 return NewFD->setInvalidDecl(); 4563 4564 // Extra checking for C++0x literal operators (C++0x [over.literal]). 4565 if (NewFD->getLiteralIdentifier() && 4566 CheckLiteralOperatorDeclaration(NewFD)) 4567 return NewFD->setInvalidDecl(); 4568 4569 // In C++, check default arguments now that we have merged decls. Unless 4570 // the lexical context is the class, because in this case this is done 4571 // during delayed parsing anyway. 4572 if (!CurContext->isRecord()) 4573 CheckCXXDefaultArguments(NewFD); 4574 4575 // If this function declares a builtin function, check the type of this 4576 // declaration against the expected type for the builtin. 4577 if (unsigned BuiltinID = NewFD->getBuiltinID()) { 4578 ASTContext::GetBuiltinTypeError Error; 4579 QualType T = Context.GetBuiltinType(BuiltinID, Error); 4580 if (!T.isNull() && !Context.hasSameType(T, NewFD->getType())) { 4581 // The type of this function differs from the type of the builtin, 4582 // so forget about the builtin entirely. 4583 Context.BuiltinInfo.ForgetBuiltin(BuiltinID, Context.Idents); 4584 } 4585 } 4586 } 4587} 4588 4589void Sema::CheckMain(FunctionDecl* FD) { 4590 // C++ [basic.start.main]p3: A program that declares main to be inline 4591 // or static is ill-formed. 4592 // C99 6.7.4p4: In a hosted environment, the inline function specifier 4593 // shall not appear in a declaration of main. 4594 // static main is not an error under C99, but we should warn about it. 4595 bool isInline = FD->isInlineSpecified(); 4596 bool isStatic = FD->getStorageClass() == SC_Static; 4597 if (isInline || isStatic) { 4598 unsigned diagID = diag::warn_unusual_main_decl; 4599 if (isInline || getLangOptions().CPlusPlus) 4600 diagID = diag::err_unusual_main_decl; 4601 4602 int which = isStatic + (isInline << 1) - 1; 4603 Diag(FD->getLocation(), diagID) << which; 4604 } 4605 4606 QualType T = FD->getType(); 4607 assert(T->isFunctionType() && "function decl is not of function type"); 4608 const FunctionType* FT = T->getAs<FunctionType>(); 4609 4610 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 4611 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 4612 FD->setInvalidDecl(true); 4613 } 4614 4615 // Treat protoless main() as nullary. 4616 if (isa<FunctionNoProtoType>(FT)) return; 4617 4618 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 4619 unsigned nparams = FTP->getNumArgs(); 4620 assert(FD->getNumParams() == nparams); 4621 4622 bool HasExtraParameters = (nparams > 3); 4623 4624 // Darwin passes an undocumented fourth argument of type char**. If 4625 // other platforms start sprouting these, the logic below will start 4626 // getting shifty. 4627 if (nparams == 4 && 4628 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 4629 HasExtraParameters = false; 4630 4631 if (HasExtraParameters) { 4632 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 4633 FD->setInvalidDecl(true); 4634 nparams = 3; 4635 } 4636 4637 // FIXME: a lot of the following diagnostics would be improved 4638 // if we had some location information about types. 4639 4640 QualType CharPP = 4641 Context.getPointerType(Context.getPointerType(Context.CharTy)); 4642 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 4643 4644 for (unsigned i = 0; i < nparams; ++i) { 4645 QualType AT = FTP->getArgType(i); 4646 4647 bool mismatch = true; 4648 4649 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 4650 mismatch = false; 4651 else if (Expected[i] == CharPP) { 4652 // As an extension, the following forms are okay: 4653 // char const ** 4654 // char const * const * 4655 // char * const * 4656 4657 QualifierCollector qs; 4658 const PointerType* PT; 4659 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 4660 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 4661 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 4662 qs.removeConst(); 4663 mismatch = !qs.empty(); 4664 } 4665 } 4666 4667 if (mismatch) { 4668 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 4669 // TODO: suggest replacing given type with expected type 4670 FD->setInvalidDecl(true); 4671 } 4672 } 4673 4674 if (nparams == 1 && !FD->isInvalidDecl()) { 4675 Diag(FD->getLocation(), diag::warn_main_one_arg); 4676 } 4677 4678 if (!FD->isInvalidDecl() && FD->getDescribedFunctionTemplate()) { 4679 Diag(FD->getLocation(), diag::err_main_template_decl); 4680 FD->setInvalidDecl(); 4681 } 4682} 4683 4684bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 4685 // FIXME: Need strict checking. In C89, we need to check for 4686 // any assignment, increment, decrement, function-calls, or 4687 // commas outside of a sizeof. In C99, it's the same list, 4688 // except that the aforementioned are allowed in unevaluated 4689 // expressions. Everything else falls under the 4690 // "may accept other forms of constant expressions" exception. 4691 // (We never end up here for C++, so the constant expression 4692 // rules there don't matter.) 4693 if (Init->isConstantInitializer(Context, false)) 4694 return false; 4695 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 4696 << Init->getSourceRange(); 4697 return true; 4698} 4699 4700namespace { 4701 // Visits an initialization expression to see if OrigDecl is evaluated in 4702 // its own initialization and throws a warning if it does. 4703 class SelfReferenceChecker 4704 : public EvaluatedExprVisitor<SelfReferenceChecker> { 4705 Sema &S; 4706 Decl *OrigDecl; 4707 4708 public: 4709 typedef EvaluatedExprVisitor<SelfReferenceChecker> Inherited; 4710 4711 SelfReferenceChecker(Sema &S, Decl *OrigDecl) : Inherited(S.Context), 4712 S(S), OrigDecl(OrigDecl) { } 4713 4714 void VisitExpr(Expr *E) { 4715 if (isa<ObjCMessageExpr>(*E)) return; 4716 Inherited::VisitExpr(E); 4717 } 4718 4719 void VisitImplicitCastExpr(ImplicitCastExpr *E) { 4720 CheckForSelfReference(E); 4721 Inherited::VisitImplicitCastExpr(E); 4722 } 4723 4724 void CheckForSelfReference(ImplicitCastExpr *E) { 4725 if (E->getCastKind() != CK_LValueToRValue) return; 4726 Expr* SubExpr = E->getSubExpr()->IgnoreParenImpCasts(); 4727 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SubExpr); 4728 if (!DRE) return; 4729 Decl* ReferenceDecl = DRE->getDecl(); 4730 if (OrigDecl != ReferenceDecl) return; 4731 LookupResult Result(S, DRE->getNameInfo(), Sema::LookupOrdinaryName, 4732 Sema::NotForRedeclaration); 4733 S.Diag(SubExpr->getLocStart(), diag::warn_uninit_self_reference_in_init) 4734 << Result.getLookupName() << OrigDecl->getLocation() 4735 << SubExpr->getSourceRange(); 4736 } 4737 }; 4738} 4739 4740/// AddInitializerToDecl - Adds the initializer Init to the 4741/// declaration dcl. If DirectInit is true, this is C++ direct 4742/// initialization rather than copy initialization. 4743void Sema::AddInitializerToDecl(Decl *RealDecl, Expr *Init, 4744 bool DirectInit, bool TypeMayContainAuto) { 4745 // If there is no declaration, there was an error parsing it. Just ignore 4746 // the initializer. 4747 if (RealDecl == 0 || RealDecl->isInvalidDecl()) 4748 return; 4749 4750 // Check for self-references within variable initializers. 4751 if (VarDecl *vd = dyn_cast<VarDecl>(RealDecl)) { 4752 // Variables declared within a function/method body are handled 4753 // by a dataflow analysis. 4754 if (!vd->hasLocalStorage() && !vd->isStaticLocal()) 4755 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 4756 } 4757 else { 4758 SelfReferenceChecker(*this, RealDecl).VisitExpr(Init); 4759 } 4760 4761 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 4762 // With declarators parsed the way they are, the parser cannot 4763 // distinguish between a normal initializer and a pure-specifier. 4764 // Thus this grotesque test. 4765 IntegerLiteral *IL; 4766 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 4767 Context.getCanonicalType(IL->getType()) == Context.IntTy) 4768 CheckPureMethod(Method, Init->getSourceRange()); 4769 else { 4770 Diag(Method->getLocation(), diag::err_member_function_initialization) 4771 << Method->getDeclName() << Init->getSourceRange(); 4772 Method->setInvalidDecl(); 4773 } 4774 return; 4775 } 4776 4777 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 4778 if (!VDecl) { 4779 if (getLangOptions().CPlusPlus && 4780 RealDecl->getLexicalDeclContext()->isRecord() && 4781 isa<NamedDecl>(RealDecl)) 4782 Diag(RealDecl->getLocation(), diag::err_member_initialization); 4783 else 4784 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 4785 RealDecl->setInvalidDecl(); 4786 return; 4787 } 4788 4789 // C++0x [decl.spec.auto]p6. Deduce the type which 'auto' stands in for. 4790 if (TypeMayContainAuto && VDecl->getType()->getContainedAutoType()) { 4791 TypeSourceInfo *DeducedType = 0; 4792 if (!DeduceAutoType(VDecl->getTypeSourceInfo(), Init, DeducedType)) 4793 Diag(VDecl->getLocation(), diag::err_auto_var_deduction_failure) 4794 << VDecl->getDeclName() << VDecl->getType() << Init->getType() 4795 << Init->getSourceRange(); 4796 if (!DeducedType) { 4797 RealDecl->setInvalidDecl(); 4798 return; 4799 } 4800 VDecl->setTypeSourceInfo(DeducedType); 4801 VDecl->setType(DeducedType->getType()); 4802 4803 // If this is a redeclaration, check that the type we just deduced matches 4804 // the previously declared type. 4805 if (VarDecl *Old = VDecl->getPreviousDeclaration()) 4806 MergeVarDeclTypes(VDecl, Old); 4807 } 4808 4809 4810 // A definition must end up with a complete type, which means it must be 4811 // complete with the restriction that an array type might be completed by the 4812 // initializer; note that later code assumes this restriction. 4813 QualType BaseDeclType = VDecl->getType(); 4814 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 4815 BaseDeclType = Array->getElementType(); 4816 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 4817 diag::err_typecheck_decl_incomplete_type)) { 4818 RealDecl->setInvalidDecl(); 4819 return; 4820 } 4821 4822 // The variable can not have an abstract class type. 4823 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 4824 diag::err_abstract_type_in_decl, 4825 AbstractVariableType)) 4826 VDecl->setInvalidDecl(); 4827 4828 const VarDecl *Def; 4829 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 4830 Diag(VDecl->getLocation(), diag::err_redefinition) 4831 << VDecl->getDeclName(); 4832 Diag(Def->getLocation(), diag::note_previous_definition); 4833 VDecl->setInvalidDecl(); 4834 return; 4835 } 4836 4837 const VarDecl* PrevInit = 0; 4838 if (getLangOptions().CPlusPlus) { 4839 // C++ [class.static.data]p4 4840 // If a static data member is of const integral or const 4841 // enumeration type, its declaration in the class definition can 4842 // specify a constant-initializer which shall be an integral 4843 // constant expression (5.19). In that case, the member can appear 4844 // in integral constant expressions. The member shall still be 4845 // defined in a namespace scope if it is used in the program and the 4846 // namespace scope definition shall not contain an initializer. 4847 // 4848 // We already performed a redefinition check above, but for static 4849 // data members we also need to check whether there was an in-class 4850 // declaration with an initializer. 4851 if (VDecl->isStaticDataMember() && VDecl->getAnyInitializer(PrevInit)) { 4852 Diag(VDecl->getLocation(), diag::err_redefinition) << VDecl->getDeclName(); 4853 Diag(PrevInit->getLocation(), diag::note_previous_definition); 4854 return; 4855 } 4856 4857 if (VDecl->hasLocalStorage()) 4858 getCurFunction()->setHasBranchProtectedScope(); 4859 4860 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer)) { 4861 VDecl->setInvalidDecl(); 4862 return; 4863 } 4864 } 4865 4866 // Capture the variable that is being initialized and the style of 4867 // initialization. 4868 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 4869 4870 // FIXME: Poor source location information. 4871 InitializationKind Kind 4872 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 4873 Init->getLocStart(), 4874 Init->getLocEnd()) 4875 : InitializationKind::CreateCopy(VDecl->getLocation(), 4876 Init->getLocStart()); 4877 4878 // Get the decls type and save a reference for later, since 4879 // CheckInitializerTypes may change it. 4880 QualType DclT = VDecl->getType(), SavT = DclT; 4881 if (VDecl->isLocalVarDecl()) { 4882 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 4883 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 4884 VDecl->setInvalidDecl(); 4885 } else if (!VDecl->isInvalidDecl()) { 4886 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4887 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4888 MultiExprArg(*this, &Init, 1), 4889 &DclT); 4890 if (Result.isInvalid()) { 4891 VDecl->setInvalidDecl(); 4892 return; 4893 } 4894 4895 Init = Result.takeAs<Expr>(); 4896 4897 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4898 // Don't check invalid declarations to avoid emitting useless diagnostics. 4899 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4900 if (VDecl->getStorageClass() == SC_Static) // C99 6.7.8p4. 4901 CheckForConstantInitializer(Init, DclT); 4902 } 4903 } 4904 } else if (VDecl->isStaticDataMember() && 4905 VDecl->getLexicalDeclContext()->isRecord()) { 4906 // This is an in-class initialization for a static data member, e.g., 4907 // 4908 // struct S { 4909 // static const int value = 17; 4910 // }; 4911 4912 // Try to perform the initialization regardless. 4913 if (!VDecl->isInvalidDecl()) { 4914 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4915 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4916 MultiExprArg(*this, &Init, 1), 4917 &DclT); 4918 if (Result.isInvalid()) { 4919 VDecl->setInvalidDecl(); 4920 return; 4921 } 4922 4923 Init = Result.takeAs<Expr>(); 4924 } 4925 4926 // C++ [class.mem]p4: 4927 // A member-declarator can contain a constant-initializer only 4928 // if it declares a static member (9.4) of const integral or 4929 // const enumeration type, see 9.4.2. 4930 QualType T = VDecl->getType(); 4931 4932 // Do nothing on dependent types. 4933 if (T->isDependentType()) { 4934 4935 // Require constness. 4936 } else if (!T.isConstQualified()) { 4937 Diag(VDecl->getLocation(), diag::err_in_class_initializer_non_const) 4938 << Init->getSourceRange(); 4939 VDecl->setInvalidDecl(); 4940 4941 // We allow integer constant expressions in all cases. 4942 } else if (T->isIntegralOrEnumerationType()) { 4943 if (!Init->isValueDependent()) { 4944 // Check whether the expression is a constant expression. 4945 llvm::APSInt Value; 4946 SourceLocation Loc; 4947 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4948 Diag(Loc, diag::err_in_class_initializer_non_constant) 4949 << Init->getSourceRange(); 4950 VDecl->setInvalidDecl(); 4951 } 4952 } 4953 4954 // We allow floating-point constants as an extension in C++03, and 4955 // C++0x has far more complicated rules that we don't really 4956 // implement fully. 4957 } else { 4958 bool Allowed = false; 4959 if (getLangOptions().CPlusPlus0x) { 4960 Allowed = T->isLiteralType(); 4961 } else if (T->isFloatingType()) { // also permits complex, which is ok 4962 Diag(VDecl->getLocation(), diag::ext_in_class_initializer_float_type) 4963 << T << Init->getSourceRange(); 4964 Allowed = true; 4965 } 4966 4967 if (!Allowed) { 4968 Diag(VDecl->getLocation(), diag::err_in_class_initializer_bad_type) 4969 << T << Init->getSourceRange(); 4970 VDecl->setInvalidDecl(); 4971 4972 // TODO: there are probably expressions that pass here that shouldn't. 4973 } else if (!Init->isValueDependent() && 4974 !Init->isConstantInitializer(Context, false)) { 4975 Diag(Init->getExprLoc(), diag::err_in_class_initializer_non_constant) 4976 << Init->getSourceRange(); 4977 VDecl->setInvalidDecl(); 4978 } 4979 } 4980 } else if (VDecl->isFileVarDecl()) { 4981 if (VDecl->getStorageClassAsWritten() == SC_Extern && 4982 (!getLangOptions().CPlusPlus || 4983 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4984 Diag(VDecl->getLocation(), diag::warn_extern_init); 4985 if (!VDecl->isInvalidDecl()) { 4986 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4987 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4988 MultiExprArg(*this, &Init, 1), 4989 &DclT); 4990 if (Result.isInvalid()) { 4991 VDecl->setInvalidDecl(); 4992 return; 4993 } 4994 4995 Init = Result.takeAs<Expr>(); 4996 } 4997 4998 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4999 // Don't check invalid declarations to avoid emitting useless diagnostics. 5000 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 5001 // C99 6.7.8p4. All file scoped initializers need to be constant. 5002 CheckForConstantInitializer(Init, DclT); 5003 } 5004 } 5005 // If the type changed, it means we had an incomplete type that was 5006 // completed by the initializer. For example: 5007 // int ary[] = { 1, 3, 5 }; 5008 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 5009 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 5010 VDecl->setType(DclT); 5011 Init->setType(DclT); 5012 } 5013 5014 5015 // If this variable is a local declaration with record type, make sure it 5016 // doesn't have a flexible member initialization. We only support this as a 5017 // global/static definition. 5018 if (VDecl->hasLocalStorage()) 5019 if (const RecordType *RT = VDecl->getType()->getAs<RecordType>()) 5020 if (RT->getDecl()->hasFlexibleArrayMember()) { 5021 // Check whether the initializer tries to initialize the flexible 5022 // array member itself to anything other than an empty initializer list. 5023 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) { 5024 unsigned Index = std::distance(RT->getDecl()->field_begin(), 5025 RT->getDecl()->field_end()) - 1; 5026 if (Index < ILE->getNumInits() && 5027 !(isa<InitListExpr>(ILE->getInit(Index)) && 5028 cast<InitListExpr>(ILE->getInit(Index))->getNumInits() == 0)) { 5029 Diag(VDecl->getLocation(), diag::err_nonstatic_flexible_variable); 5030 VDecl->setInvalidDecl(); 5031 } 5032 } 5033 } 5034 5035 // Check any implicit conversions within the expression. 5036 CheckImplicitConversions(Init, VDecl->getLocation()); 5037 5038 Init = MaybeCreateExprWithCleanups(Init); 5039 // Attach the initializer to the decl. 5040 VDecl->setInit(Init); 5041 5042 CheckCompleteVariableDeclaration(VDecl); 5043} 5044 5045/// ActOnInitializerError - Given that there was an error parsing an 5046/// initializer for the given declaration, try to return to some form 5047/// of sanity. 5048void Sema::ActOnInitializerError(Decl *D) { 5049 // Our main concern here is re-establishing invariants like "a 5050 // variable's type is either dependent or complete". 5051 if (!D || D->isInvalidDecl()) return; 5052 5053 VarDecl *VD = dyn_cast<VarDecl>(D); 5054 if (!VD) return; 5055 5056 // Auto types are meaningless if we can't make sense of the initializer. 5057 if (ParsingInitForAutoVars.count(D)) { 5058 D->setInvalidDecl(); 5059 return; 5060 } 5061 5062 QualType Ty = VD->getType(); 5063 if (Ty->isDependentType()) return; 5064 5065 // Require a complete type. 5066 if (RequireCompleteType(VD->getLocation(), 5067 Context.getBaseElementType(Ty), 5068 diag::err_typecheck_decl_incomplete_type)) { 5069 VD->setInvalidDecl(); 5070 return; 5071 } 5072 5073 // Require an abstract type. 5074 if (RequireNonAbstractType(VD->getLocation(), Ty, 5075 diag::err_abstract_type_in_decl, 5076 AbstractVariableType)) { 5077 VD->setInvalidDecl(); 5078 return; 5079 } 5080 5081 // Don't bother complaining about constructors or destructors, 5082 // though. 5083} 5084 5085void Sema::ActOnUninitializedDecl(Decl *RealDecl, 5086 bool TypeMayContainAuto) { 5087 // If there is no declaration, there was an error parsing it. Just ignore it. 5088 if (RealDecl == 0) 5089 return; 5090 5091 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 5092 QualType Type = Var->getType(); 5093 5094 // C++0x [dcl.spec.auto]p3 5095 if (TypeMayContainAuto && Type->getContainedAutoType()) { 5096 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 5097 << Var->getDeclName() << Type; 5098 Var->setInvalidDecl(); 5099 return; 5100 } 5101 5102 switch (Var->isThisDeclarationADefinition()) { 5103 case VarDecl::Definition: 5104 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 5105 break; 5106 5107 // We have an out-of-line definition of a static data member 5108 // that has an in-class initializer, so we type-check this like 5109 // a declaration. 5110 // 5111 // Fall through 5112 5113 case VarDecl::DeclarationOnly: 5114 // It's only a declaration. 5115 5116 // Block scope. C99 6.7p7: If an identifier for an object is 5117 // declared with no linkage (C99 6.2.2p6), the type for the 5118 // object shall be complete. 5119 if (!Type->isDependentType() && Var->isLocalVarDecl() && 5120 !Var->getLinkage() && !Var->isInvalidDecl() && 5121 RequireCompleteType(Var->getLocation(), Type, 5122 diag::err_typecheck_decl_incomplete_type)) 5123 Var->setInvalidDecl(); 5124 5125 // Make sure that the type is not abstract. 5126 if (!Type->isDependentType() && !Var->isInvalidDecl() && 5127 RequireNonAbstractType(Var->getLocation(), Type, 5128 diag::err_abstract_type_in_decl, 5129 AbstractVariableType)) 5130 Var->setInvalidDecl(); 5131 return; 5132 5133 case VarDecl::TentativeDefinition: 5134 // File scope. C99 6.9.2p2: A declaration of an identifier for an 5135 // object that has file scope without an initializer, and without a 5136 // storage-class specifier or with the storage-class specifier "static", 5137 // constitutes a tentative definition. Note: A tentative definition with 5138 // external linkage is valid (C99 6.2.2p5). 5139 if (!Var->isInvalidDecl()) { 5140 if (const IncompleteArrayType *ArrayT 5141 = Context.getAsIncompleteArrayType(Type)) { 5142 if (RequireCompleteType(Var->getLocation(), 5143 ArrayT->getElementType(), 5144 diag::err_illegal_decl_array_incomplete_type)) 5145 Var->setInvalidDecl(); 5146 } else if (Var->getStorageClass() == SC_Static) { 5147 // C99 6.9.2p3: If the declaration of an identifier for an object is 5148 // a tentative definition and has internal linkage (C99 6.2.2p3), the 5149 // declared type shall not be an incomplete type. 5150 // NOTE: code such as the following 5151 // static struct s; 5152 // struct s { int a; }; 5153 // is accepted by gcc. Hence here we issue a warning instead of 5154 // an error and we do not invalidate the static declaration. 5155 // NOTE: to avoid multiple warnings, only check the first declaration. 5156 if (Var->getPreviousDeclaration() == 0) 5157 RequireCompleteType(Var->getLocation(), Type, 5158 diag::ext_typecheck_decl_incomplete_type); 5159 } 5160 } 5161 5162 // Record the tentative definition; we're done. 5163 if (!Var->isInvalidDecl()) 5164 TentativeDefinitions.push_back(Var); 5165 return; 5166 } 5167 5168 // Provide a specific diagnostic for uninitialized variable 5169 // definitions with incomplete array type. 5170 if (Type->isIncompleteArrayType()) { 5171 Diag(Var->getLocation(), 5172 diag::err_typecheck_incomplete_array_needs_initializer); 5173 Var->setInvalidDecl(); 5174 return; 5175 } 5176 5177 // Provide a specific diagnostic for uninitialized variable 5178 // definitions with reference type. 5179 if (Type->isReferenceType()) { 5180 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 5181 << Var->getDeclName() 5182 << SourceRange(Var->getLocation(), Var->getLocation()); 5183 Var->setInvalidDecl(); 5184 return; 5185 } 5186 5187 // Do not attempt to type-check the default initializer for a 5188 // variable with dependent type. 5189 if (Type->isDependentType()) 5190 return; 5191 5192 if (Var->isInvalidDecl()) 5193 return; 5194 5195 if (RequireCompleteType(Var->getLocation(), 5196 Context.getBaseElementType(Type), 5197 diag::err_typecheck_decl_incomplete_type)) { 5198 Var->setInvalidDecl(); 5199 return; 5200 } 5201 5202 // The variable can not have an abstract class type. 5203 if (RequireNonAbstractType(Var->getLocation(), Type, 5204 diag::err_abstract_type_in_decl, 5205 AbstractVariableType)) { 5206 Var->setInvalidDecl(); 5207 return; 5208 } 5209 5210 const RecordType *Record 5211 = Context.getBaseElementType(Type)->getAs<RecordType>(); 5212 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 5213 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 5214 // C++03 [dcl.init]p9: 5215 // If no initializer is specified for an object, and the 5216 // object is of (possibly cv-qualified) non-POD class type (or 5217 // array thereof), the object shall be default-initialized; if 5218 // the object is of const-qualified type, the underlying class 5219 // type shall have a user-declared default 5220 // constructor. Otherwise, if no initializer is specified for 5221 // a non- static object, the object and its subobjects, if 5222 // any, have an indeterminate initial value); if the object 5223 // or any of its subobjects are of const-qualified type, the 5224 // program is ill-formed. 5225 // FIXME: DPG thinks it is very fishy that C++0x disables this. 5226 } else { 5227 // Check for jumps past the implicit initializer. C++0x 5228 // clarifies that this applies to a "variable with automatic 5229 // storage duration", not a "local variable". 5230 if (getLangOptions().CPlusPlus && Var->hasLocalStorage()) 5231 getCurFunction()->setHasBranchProtectedScope(); 5232 5233 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 5234 InitializationKind Kind 5235 = InitializationKind::CreateDefault(Var->getLocation()); 5236 5237 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 5238 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, 5239 MultiExprArg(*this, 0, 0)); 5240 if (Init.isInvalid()) 5241 Var->setInvalidDecl(); 5242 else if (Init.get()) 5243 Var->setInit(MaybeCreateExprWithCleanups(Init.get())); 5244 } 5245 5246 CheckCompleteVariableDeclaration(Var); 5247 } 5248} 5249 5250void Sema::CheckCompleteVariableDeclaration(VarDecl *var) { 5251 if (var->isInvalidDecl()) return; 5252 5253 // All the following checks are C++ only. 5254 if (!getLangOptions().CPlusPlus) return; 5255 5256 QualType baseType = Context.getBaseElementType(var->getType()); 5257 if (baseType->isDependentType()) return; 5258 5259 // __block variables might require us to capture a copy-initializer. 5260 if (var->hasAttr<BlocksAttr>()) { 5261 // It's currently invalid to ever have a __block variable with an 5262 // array type; should we diagnose that here? 5263 5264 // Regardless, we don't want to ignore array nesting when 5265 // constructing this copy. 5266 QualType type = var->getType(); 5267 5268 if (type->isStructureOrClassType()) { 5269 SourceLocation poi = var->getLocation(); 5270 Expr *varRef = new (Context) DeclRefExpr(var, type, VK_LValue, poi); 5271 ExprResult result = 5272 PerformCopyInitialization( 5273 InitializedEntity::InitializeBlock(poi, type, false), 5274 poi, Owned(varRef)); 5275 if (!result.isInvalid()) { 5276 result = MaybeCreateExprWithCleanups(result); 5277 Expr *init = result.takeAs<Expr>(); 5278 Context.setBlockVarCopyInits(var, init); 5279 } 5280 } 5281 } 5282 5283 // Check for global constructors. 5284 if (!var->getDeclContext()->isDependentContext() && 5285 var->hasGlobalStorage() && 5286 !var->isStaticLocal() && 5287 var->getInit() && 5288 !var->getInit()->isConstantInitializer(Context, 5289 baseType->isReferenceType())) 5290 Diag(var->getLocation(), diag::warn_global_constructor) 5291 << var->getInit()->getSourceRange(); 5292 5293 // Require the destructor. 5294 if (const RecordType *recordType = baseType->getAs<RecordType>()) 5295 FinalizeVarWithDestructor(var, recordType); 5296} 5297 5298/// FinalizeDeclaration - called by ParseDeclarationAfterDeclarator to perform 5299/// any semantic actions necessary after any initializer has been attached. 5300void 5301Sema::FinalizeDeclaration(Decl *ThisDecl) { 5302 // Note that we are no longer parsing the initializer for this declaration. 5303 ParsingInitForAutoVars.erase(ThisDecl); 5304} 5305 5306Sema::DeclGroupPtrTy 5307Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 5308 Decl **Group, unsigned NumDecls) { 5309 llvm::SmallVector<Decl*, 8> Decls; 5310 5311 if (DS.isTypeSpecOwned()) 5312 Decls.push_back(DS.getRepAsDecl()); 5313 5314 for (unsigned i = 0; i != NumDecls; ++i) 5315 if (Decl *D = Group[i]) 5316 Decls.push_back(D); 5317 5318 return BuildDeclaratorGroup(Decls.data(), Decls.size(), 5319 DS.getTypeSpecType() == DeclSpec::TST_auto); 5320} 5321 5322/// BuildDeclaratorGroup - convert a list of declarations into a declaration 5323/// group, performing any necessary semantic checking. 5324Sema::DeclGroupPtrTy 5325Sema::BuildDeclaratorGroup(Decl **Group, unsigned NumDecls, 5326 bool TypeMayContainAuto) { 5327 // C++0x [dcl.spec.auto]p7: 5328 // If the type deduced for the template parameter U is not the same in each 5329 // deduction, the program is ill-formed. 5330 // FIXME: When initializer-list support is added, a distinction is needed 5331 // between the deduced type U and the deduced type which 'auto' stands for. 5332 // auto a = 0, b = { 1, 2, 3 }; 5333 // is legal because the deduced type U is 'int' in both cases. 5334 if (TypeMayContainAuto && NumDecls > 1) { 5335 QualType Deduced; 5336 CanQualType DeducedCanon; 5337 VarDecl *DeducedDecl = 0; 5338 for (unsigned i = 0; i != NumDecls; ++i) { 5339 if (VarDecl *D = dyn_cast<VarDecl>(Group[i])) { 5340 AutoType *AT = D->getType()->getContainedAutoType(); 5341 // Don't reissue diagnostics when instantiating a template. 5342 if (AT && D->isInvalidDecl()) 5343 break; 5344 if (AT && AT->isDeduced()) { 5345 QualType U = AT->getDeducedType(); 5346 CanQualType UCanon = Context.getCanonicalType(U); 5347 if (Deduced.isNull()) { 5348 Deduced = U; 5349 DeducedCanon = UCanon; 5350 DeducedDecl = D; 5351 } else if (DeducedCanon != UCanon) { 5352 Diag(D->getTypeSourceInfo()->getTypeLoc().getBeginLoc(), 5353 diag::err_auto_different_deductions) 5354 << Deduced << DeducedDecl->getDeclName() 5355 << U << D->getDeclName() 5356 << DeducedDecl->getInit()->getSourceRange() 5357 << D->getInit()->getSourceRange(); 5358 D->setInvalidDecl(); 5359 break; 5360 } 5361 } 5362 } 5363 } 5364 } 5365 5366 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, Group, NumDecls)); 5367} 5368 5369 5370/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 5371/// to introduce parameters into function prototype scope. 5372Decl *Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 5373 const DeclSpec &DS = D.getDeclSpec(); 5374 5375 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 5376 VarDecl::StorageClass StorageClass = SC_None; 5377 VarDecl::StorageClass StorageClassAsWritten = SC_None; 5378 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 5379 StorageClass = SC_Register; 5380 StorageClassAsWritten = SC_Register; 5381 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 5382 Diag(DS.getStorageClassSpecLoc(), 5383 diag::err_invalid_storage_class_in_func_decl); 5384 D.getMutableDeclSpec().ClearStorageClassSpecs(); 5385 } 5386 5387 if (D.getDeclSpec().isThreadSpecified()) 5388 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5389 5390 DiagnoseFunctionSpecifiers(D); 5391 5392 TagDecl *OwnedDecl = 0; 5393 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 5394 QualType parmDeclType = TInfo->getType(); 5395 5396 if (getLangOptions().CPlusPlus) { 5397 // Check that there are no default arguments inside the type of this 5398 // parameter. 5399 CheckExtraCXXDefaultArguments(D); 5400 5401 if (OwnedDecl && OwnedDecl->isDefinition()) { 5402 // C++ [dcl.fct]p6: 5403 // Types shall not be defined in return or parameter types. 5404 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 5405 << Context.getTypeDeclType(OwnedDecl); 5406 } 5407 5408 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 5409 if (D.getCXXScopeSpec().isSet()) { 5410 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 5411 << D.getCXXScopeSpec().getRange(); 5412 D.getCXXScopeSpec().clear(); 5413 } 5414 } 5415 5416 // Ensure we have a valid name 5417 IdentifierInfo *II = 0; 5418 if (D.hasName()) { 5419 II = D.getIdentifier(); 5420 if (!II) { 5421 Diag(D.getIdentifierLoc(), diag::err_bad_parameter_name) 5422 << GetNameForDeclarator(D).getName().getAsString(); 5423 D.setInvalidType(true); 5424 } 5425 } 5426 5427 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 5428 if (II) { 5429 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 5430 ForRedeclaration); 5431 LookupName(R, S); 5432 if (R.isSingleResult()) { 5433 NamedDecl *PrevDecl = R.getFoundDecl(); 5434 if (PrevDecl->isTemplateParameter()) { 5435 // Maybe we will complain about the shadowed template parameter. 5436 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5437 // Just pretend that we didn't see the previous declaration. 5438 PrevDecl = 0; 5439 } else if (S->isDeclScope(PrevDecl)) { 5440 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 5441 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5442 5443 // Recover by removing the name 5444 II = 0; 5445 D.SetIdentifier(0, D.getIdentifierLoc()); 5446 D.setInvalidType(true); 5447 } 5448 } 5449 } 5450 5451 // Temporarily put parameter variables in the translation unit, not 5452 // the enclosing context. This prevents them from accidentally 5453 // looking like class members in C++. 5454 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 5455 D.getSourceRange().getBegin(), 5456 D.getIdentifierLoc(), II, 5457 parmDeclType, TInfo, 5458 StorageClass, StorageClassAsWritten); 5459 5460 if (D.isInvalidType()) 5461 New->setInvalidDecl(); 5462 5463 // Add the parameter declaration into this scope. 5464 S->AddDecl(New); 5465 if (II) 5466 IdResolver.AddDecl(New); 5467 5468 ProcessDeclAttributes(S, New, D); 5469 5470 if (New->hasAttr<BlocksAttr>()) { 5471 Diag(New->getLocation(), diag::err_block_on_nonlocal); 5472 } 5473 return New; 5474} 5475 5476/// \brief Synthesizes a variable for a parameter arising from a 5477/// typedef. 5478ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 5479 SourceLocation Loc, 5480 QualType T) { 5481 /* FIXME: setting StartLoc == Loc. 5482 Would it be worth to modify callers so as to provide proper source 5483 location for the unnamed parameters, embedding the parameter's type? */ 5484 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, Loc, 0, 5485 T, Context.getTrivialTypeSourceInfo(T, Loc), 5486 SC_None, SC_None, 0); 5487 Param->setImplicit(); 5488 return Param; 5489} 5490 5491void Sema::DiagnoseUnusedParameters(ParmVarDecl * const *Param, 5492 ParmVarDecl * const *ParamEnd) { 5493 // Don't diagnose unused-parameter errors in template instantiations; we 5494 // will already have done so in the template itself. 5495 if (!ActiveTemplateInstantiations.empty()) 5496 return; 5497 5498 for (; Param != ParamEnd; ++Param) { 5499 if (!(*Param)->isUsed() && (*Param)->getDeclName() && 5500 !(*Param)->hasAttr<UnusedAttr>()) { 5501 Diag((*Param)->getLocation(), diag::warn_unused_parameter) 5502 << (*Param)->getDeclName(); 5503 } 5504 } 5505} 5506 5507void Sema::DiagnoseSizeOfParametersAndReturnValue(ParmVarDecl * const *Param, 5508 ParmVarDecl * const *ParamEnd, 5509 QualType ReturnTy, 5510 NamedDecl *D) { 5511 if (LangOpts.NumLargeByValueCopy == 0) // No check. 5512 return; 5513 5514 // Warn if the return value is pass-by-value and larger than the specified 5515 // threshold. 5516 if (ReturnTy->isPODType()) { 5517 unsigned Size = Context.getTypeSizeInChars(ReturnTy).getQuantity(); 5518 if (Size > LangOpts.NumLargeByValueCopy) 5519 Diag(D->getLocation(), diag::warn_return_value_size) 5520 << D->getDeclName() << Size; 5521 } 5522 5523 // Warn if any parameter is pass-by-value and larger than the specified 5524 // threshold. 5525 for (; Param != ParamEnd; ++Param) { 5526 QualType T = (*Param)->getType(); 5527 if (!T->isPODType()) 5528 continue; 5529 unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); 5530 if (Size > LangOpts.NumLargeByValueCopy) 5531 Diag((*Param)->getLocation(), diag::warn_parameter_size) 5532 << (*Param)->getDeclName() << Size; 5533 } 5534} 5535 5536ParmVarDecl *Sema::CheckParameter(DeclContext *DC, SourceLocation StartLoc, 5537 SourceLocation NameLoc, IdentifierInfo *Name, 5538 QualType T, TypeSourceInfo *TSInfo, 5539 VarDecl::StorageClass StorageClass, 5540 VarDecl::StorageClass StorageClassAsWritten) { 5541 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, StartLoc, NameLoc, Name, 5542 adjustParameterType(T), TSInfo, 5543 StorageClass, StorageClassAsWritten, 5544 0); 5545 5546 // Parameters can not be abstract class types. 5547 // For record types, this is done by the AbstractClassUsageDiagnoser once 5548 // the class has been completely parsed. 5549 if (!CurContext->isRecord() && 5550 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 5551 AbstractParamType)) 5552 New->setInvalidDecl(); 5553 5554 // Parameter declarators cannot be interface types. All ObjC objects are 5555 // passed by reference. 5556 if (T->isObjCObjectType()) { 5557 Diag(NameLoc, 5558 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 5559 New->setInvalidDecl(); 5560 } 5561 5562 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 5563 // duration shall not be qualified by an address-space qualifier." 5564 // Since all parameters have automatic store duration, they can not have 5565 // an address space. 5566 if (T.getAddressSpace() != 0) { 5567 Diag(NameLoc, diag::err_arg_with_address_space); 5568 New->setInvalidDecl(); 5569 } 5570 5571 return New; 5572} 5573 5574void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 5575 SourceLocation LocAfterDecls) { 5576 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo(); 5577 5578 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 5579 // for a K&R function. 5580 if (!FTI.hasPrototype) { 5581 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 5582 --i; 5583 if (FTI.ArgInfo[i].Param == 0) { 5584 llvm::SmallString<256> Code; 5585 llvm::raw_svector_ostream(Code) << " int " 5586 << FTI.ArgInfo[i].Ident->getName() 5587 << ";\n"; 5588 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 5589 << FTI.ArgInfo[i].Ident 5590 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 5591 5592 // Implicitly declare the argument as type 'int' for lack of a better 5593 // type. 5594 AttributeFactory attrs; 5595 DeclSpec DS(attrs); 5596 const char* PrevSpec; // unused 5597 unsigned DiagID; // unused 5598 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 5599 PrevSpec, DiagID); 5600 Declarator ParamD(DS, Declarator::KNRTypeListContext); 5601 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 5602 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 5603 } 5604 } 5605 } 5606} 5607 5608Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 5609 Declarator &D) { 5610 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 5611 assert(D.isFunctionDeclarator() && "Not a function declarator!"); 5612 Scope *ParentScope = FnBodyScope->getParent(); 5613 5614 Decl *DP = HandleDeclarator(ParentScope, D, 5615 MultiTemplateParamsArg(*this), 5616 /*IsFunctionDefinition=*/true); 5617 return ActOnStartOfFunctionDef(FnBodyScope, DP); 5618} 5619 5620static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 5621 // Don't warn about invalid declarations. 5622 if (FD->isInvalidDecl()) 5623 return false; 5624 5625 // Or declarations that aren't global. 5626 if (!FD->isGlobal()) 5627 return false; 5628 5629 // Don't warn about C++ member functions. 5630 if (isa<CXXMethodDecl>(FD)) 5631 return false; 5632 5633 // Don't warn about 'main'. 5634 if (FD->isMain()) 5635 return false; 5636 5637 // Don't warn about inline functions. 5638 if (FD->isInlined()) 5639 return false; 5640 5641 // Don't warn about function templates. 5642 if (FD->getDescribedFunctionTemplate()) 5643 return false; 5644 5645 // Don't warn about function template specializations. 5646 if (FD->isFunctionTemplateSpecialization()) 5647 return false; 5648 5649 bool MissingPrototype = true; 5650 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 5651 Prev; Prev = Prev->getPreviousDeclaration()) { 5652 // Ignore any declarations that occur in function or method 5653 // scope, because they aren't visible from the header. 5654 if (Prev->getDeclContext()->isFunctionOrMethod()) 5655 continue; 5656 5657 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 5658 break; 5659 } 5660 5661 return MissingPrototype; 5662} 5663 5664Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) { 5665 // Clear the last template instantiation error context. 5666 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 5667 5668 if (!D) 5669 return D; 5670 FunctionDecl *FD = 0; 5671 5672 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) 5673 FD = FunTmpl->getTemplatedDecl(); 5674 else 5675 FD = cast<FunctionDecl>(D); 5676 5677 // Enter a new function scope 5678 PushFunctionScope(); 5679 5680 // See if this is a redefinition. 5681 // But don't complain if we're in GNU89 mode and the previous definition 5682 // was an extern inline function. 5683 const FunctionDecl *Definition; 5684 if (FD->hasBody(Definition) && 5685 !canRedefineFunction(Definition, getLangOptions())) { 5686 if (getLangOptions().GNUMode && Definition->isInlineSpecified() && 5687 Definition->getStorageClass() == SC_Extern) 5688 Diag(FD->getLocation(), diag::err_redefinition_extern_inline) 5689 << FD->getDeclName() << getLangOptions().CPlusPlus; 5690 else 5691 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 5692 Diag(Definition->getLocation(), diag::note_previous_definition); 5693 } 5694 5695 // Builtin functions cannot be defined. 5696 if (unsigned BuiltinID = FD->getBuiltinID()) { 5697 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 5698 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 5699 FD->setInvalidDecl(); 5700 } 5701 } 5702 5703 // The return type of a function definition must be complete 5704 // (C99 6.9.1p3, C++ [dcl.fct]p6). 5705 QualType ResultType = FD->getResultType(); 5706 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 5707 !FD->isInvalidDecl() && 5708 RequireCompleteType(FD->getLocation(), ResultType, 5709 diag::err_func_def_incomplete_result)) 5710 FD->setInvalidDecl(); 5711 5712 // GNU warning -Wmissing-prototypes: 5713 // Warn if a global function is defined without a previous 5714 // prototype declaration. This warning is issued even if the 5715 // definition itself provides a prototype. The aim is to detect 5716 // global functions that fail to be declared in header files. 5717 if (ShouldWarnAboutMissingPrototype(FD)) 5718 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 5719 5720 if (FnBodyScope) 5721 PushDeclContext(FnBodyScope, FD); 5722 5723 // Check the validity of our function parameters 5724 CheckParmsForFunctionDef(FD->param_begin(), FD->param_end(), 5725 /*CheckParameterNames=*/true); 5726 5727 // Introduce our parameters into the function scope 5728 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 5729 ParmVarDecl *Param = FD->getParamDecl(p); 5730 Param->setOwningFunction(FD); 5731 5732 // If this has an identifier, add it to the scope stack. 5733 if (Param->getIdentifier() && FnBodyScope) { 5734 CheckShadow(FnBodyScope, Param); 5735 5736 PushOnScopeChains(Param, FnBodyScope); 5737 } 5738 } 5739 5740 // Checking attributes of current function definition 5741 // dllimport attribute. 5742 DLLImportAttr *DA = FD->getAttr<DLLImportAttr>(); 5743 if (DA && (!FD->getAttr<DLLExportAttr>())) { 5744 // dllimport attribute cannot be directly applied to definition. 5745 // Microsoft accepts dllimport for functions defined within class scope. 5746 if (!DA->isInherited() && 5747 !(LangOpts.Microsoft && FD->getLexicalDeclContext()->isRecord())) { 5748 Diag(FD->getLocation(), 5749 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 5750 << "dllimport"; 5751 FD->setInvalidDecl(); 5752 return FD; 5753 } 5754 5755 // Visual C++ appears to not think this is an issue, so only issue 5756 // a warning when Microsoft extensions are disabled. 5757 if (!LangOpts.Microsoft) { 5758 // If a symbol previously declared dllimport is later defined, the 5759 // attribute is ignored in subsequent references, and a warning is 5760 // emitted. 5761 Diag(FD->getLocation(), 5762 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 5763 << FD->getName() << "dllimport"; 5764 } 5765 } 5766 return FD; 5767} 5768 5769/// \brief Given the set of return statements within a function body, 5770/// compute the variables that are subject to the named return value 5771/// optimization. 5772/// 5773/// Each of the variables that is subject to the named return value 5774/// optimization will be marked as NRVO variables in the AST, and any 5775/// return statement that has a marked NRVO variable as its NRVO candidate can 5776/// use the named return value optimization. 5777/// 5778/// This function applies a very simplistic algorithm for NRVO: if every return 5779/// statement in the function has the same NRVO candidate, that candidate is 5780/// the NRVO variable. 5781/// 5782/// FIXME: Employ a smarter algorithm that accounts for multiple return 5783/// statements and the lifetimes of the NRVO candidates. We should be able to 5784/// find a maximal set of NRVO variables. 5785static void ComputeNRVO(Stmt *Body, FunctionScopeInfo *Scope) { 5786 ReturnStmt **Returns = Scope->Returns.data(); 5787 5788 const VarDecl *NRVOCandidate = 0; 5789 for (unsigned I = 0, E = Scope->Returns.size(); I != E; ++I) { 5790 if (!Returns[I]->getNRVOCandidate()) 5791 return; 5792 5793 if (!NRVOCandidate) 5794 NRVOCandidate = Returns[I]->getNRVOCandidate(); 5795 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 5796 return; 5797 } 5798 5799 if (NRVOCandidate) 5800 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 5801} 5802 5803Decl *Sema::ActOnFinishFunctionBody(Decl *D, Stmt *BodyArg) { 5804 return ActOnFinishFunctionBody(D, move(BodyArg), false); 5805} 5806 5807Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body, 5808 bool IsInstantiation) { 5809 FunctionDecl *FD = 0; 5810 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 5811 if (FunTmpl) 5812 FD = FunTmpl->getTemplatedDecl(); 5813 else 5814 FD = dyn_cast_or_null<FunctionDecl>(dcl); 5815 5816 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 5817 sema::AnalysisBasedWarnings::Policy *ActivePolicy = 0; 5818 5819 if (FD) { 5820 FD->setBody(Body); 5821 if (FD->isMain()) { 5822 // C and C++ allow for main to automagically return 0. 5823 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 5824 FD->setHasImplicitReturnZero(true); 5825 WP.disableCheckFallThrough(); 5826 } 5827 5828 if (!FD->isInvalidDecl()) { 5829 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 5830 DiagnoseSizeOfParametersAndReturnValue(FD->param_begin(), FD->param_end(), 5831 FD->getResultType(), FD); 5832 5833 // If this is a constructor, we need a vtable. 5834 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 5835 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 5836 5837 ComputeNRVO(Body, getCurFunction()); 5838 } 5839 5840 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 5841 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 5842 assert(MD == getCurMethodDecl() && "Method parsing confused"); 5843 MD->setBody(Body); 5844 if (Body) 5845 MD->setEndLoc(Body->getLocEnd()); 5846 if (!MD->isInvalidDecl()) { 5847 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 5848 DiagnoseSizeOfParametersAndReturnValue(MD->param_begin(), MD->param_end(), 5849 MD->getResultType(), MD); 5850 } 5851 } else { 5852 return 0; 5853 } 5854 5855 // Verify and clean out per-function state. 5856 if (Body) { 5857 // C++ constructors that have function-try-blocks can't have return 5858 // statements in the handlers of that block. (C++ [except.handle]p14) 5859 // Verify this. 5860 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 5861 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 5862 5863 // Verify that that gotos and switch cases don't jump into scopes illegally. 5864 // Verify that that gotos and switch cases don't jump into scopes illegally. 5865 if (getCurFunction()->NeedsScopeChecking() && 5866 !dcl->isInvalidDecl() && 5867 !hasAnyErrorsInThisFunction()) 5868 DiagnoseInvalidJumps(Body); 5869 5870 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) { 5871 if (!Destructor->getParent()->isDependentType()) 5872 CheckDestructor(Destructor); 5873 5874 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 5875 Destructor->getParent()); 5876 } 5877 5878 // If any errors have occurred, clear out any temporaries that may have 5879 // been leftover. This ensures that these temporaries won't be picked up for 5880 // deletion in some later function. 5881 if (PP.getDiagnostics().hasErrorOccurred() || 5882 PP.getDiagnostics().getSuppressAllDiagnostics()) 5883 ExprTemporaries.clear(); 5884 else if (!isa<FunctionTemplateDecl>(dcl)) { 5885 // Since the body is valid, issue any analysis-based warnings that are 5886 // enabled. 5887 ActivePolicy = &WP; 5888 } 5889 5890 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 5891 } 5892 5893 if (!IsInstantiation) 5894 PopDeclContext(); 5895 5896 PopFunctionOrBlockScope(ActivePolicy, dcl); 5897 5898 // If any errors have occurred, clear out any temporaries that may have 5899 // been leftover. This ensures that these temporaries won't be picked up for 5900 // deletion in some later function. 5901 if (getDiagnostics().hasErrorOccurred()) 5902 ExprTemporaries.clear(); 5903 5904 return dcl; 5905} 5906 5907/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 5908/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 5909NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 5910 IdentifierInfo &II, Scope *S) { 5911 // Before we produce a declaration for an implicitly defined 5912 // function, see whether there was a locally-scoped declaration of 5913 // this name as a function or variable. If so, use that 5914 // (non-visible) declaration, and complain about it. 5915 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 5916 = LocallyScopedExternalDecls.find(&II); 5917 if (Pos != LocallyScopedExternalDecls.end()) { 5918 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 5919 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 5920 return Pos->second; 5921 } 5922 5923 // Extension in C99. Legal in C90, but warn about it. 5924 if (II.getName().startswith("__builtin_")) 5925 Diag(Loc, diag::warn_builtin_unknown) << &II; 5926 else if (getLangOptions().C99) 5927 Diag(Loc, diag::ext_implicit_function_decl) << &II; 5928 else 5929 Diag(Loc, diag::warn_implicit_function_decl) << &II; 5930 5931 // Set a Declarator for the implicit definition: int foo(); 5932 const char *Dummy; 5933 AttributeFactory attrFactory; 5934 DeclSpec DS(attrFactory); 5935 unsigned DiagID; 5936 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 5937 (void)Error; // Silence warning. 5938 assert(!Error && "Error setting up implicit decl!"); 5939 Declarator D(DS, Declarator::BlockContext); 5940 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 5941 0, 0, true, SourceLocation(), 5942 EST_None, SourceLocation(), 5943 0, 0, 0, 0, Loc, Loc, D), 5944 DS.getAttributes(), 5945 SourceLocation()); 5946 D.SetIdentifier(&II, Loc); 5947 5948 // Insert this function into translation-unit scope. 5949 5950 DeclContext *PrevDC = CurContext; 5951 CurContext = Context.getTranslationUnitDecl(); 5952 5953 FunctionDecl *FD = dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D)); 5954 FD->setImplicit(); 5955 5956 CurContext = PrevDC; 5957 5958 AddKnownFunctionAttributes(FD); 5959 5960 return FD; 5961} 5962 5963/// \brief Adds any function attributes that we know a priori based on 5964/// the declaration of this function. 5965/// 5966/// These attributes can apply both to implicitly-declared builtins 5967/// (like __builtin___printf_chk) or to library-declared functions 5968/// like NSLog or printf. 5969void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 5970 if (FD->isInvalidDecl()) 5971 return; 5972 5973 // If this is a built-in function, map its builtin attributes to 5974 // actual attributes. 5975 if (unsigned BuiltinID = FD->getBuiltinID()) { 5976 // Handle printf-formatting attributes. 5977 unsigned FormatIdx; 5978 bool HasVAListArg; 5979 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 5980 if (!FD->getAttr<FormatAttr>()) 5981 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5982 "printf", FormatIdx+1, 5983 HasVAListArg ? 0 : FormatIdx+2)); 5984 } 5985 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 5986 HasVAListArg)) { 5987 if (!FD->getAttr<FormatAttr>()) 5988 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 5989 "scanf", FormatIdx+1, 5990 HasVAListArg ? 0 : FormatIdx+2)); 5991 } 5992 5993 // Mark const if we don't care about errno and that is the only 5994 // thing preventing the function from being const. This allows 5995 // IRgen to use LLVM intrinsics for such functions. 5996 if (!getLangOptions().MathErrno && 5997 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 5998 if (!FD->getAttr<ConstAttr>()) 5999 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 6000 } 6001 6002 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 6003 FD->addAttr(::new (Context) NoThrowAttr(FD->getLocation(), Context)); 6004 if (Context.BuiltinInfo.isConst(BuiltinID)) 6005 FD->addAttr(::new (Context) ConstAttr(FD->getLocation(), Context)); 6006 } 6007 6008 IdentifierInfo *Name = FD->getIdentifier(); 6009 if (!Name) 6010 return; 6011 if ((!getLangOptions().CPlusPlus && 6012 FD->getDeclContext()->isTranslationUnit()) || 6013 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 6014 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 6015 LinkageSpecDecl::lang_c)) { 6016 // Okay: this could be a libc/libm/Objective-C function we know 6017 // about. 6018 } else 6019 return; 6020 6021 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 6022 // FIXME: NSLog and NSLogv should be target specific 6023 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 6024 // FIXME: We known better than our headers. 6025 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 6026 } else 6027 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6028 "printf", 1, 6029 Name->isStr("NSLogv") ? 0 : 2)); 6030 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 6031 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 6032 // target-specific builtins, perhaps? 6033 if (!FD->getAttr<FormatAttr>()) 6034 FD->addAttr(::new (Context) FormatAttr(FD->getLocation(), Context, 6035 "printf", 2, 6036 Name->isStr("vasprintf") ? 0 : 3)); 6037 } 6038} 6039 6040TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 6041 TypeSourceInfo *TInfo) { 6042 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 6043 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 6044 6045 if (!TInfo) { 6046 assert(D.isInvalidType() && "no declarator info for valid type"); 6047 TInfo = Context.getTrivialTypeSourceInfo(T); 6048 } 6049 6050 // Scope manipulation handled by caller. 6051 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 6052 D.getSourceRange().getBegin(), 6053 D.getIdentifierLoc(), 6054 D.getIdentifier(), 6055 TInfo); 6056 6057 // Bail out immediately if we have an invalid declaration. 6058 if (D.isInvalidType()) { 6059 NewTD->setInvalidDecl(); 6060 return NewTD; 6061 } 6062 6063 // C++ [dcl.typedef]p8: 6064 // If the typedef declaration defines an unnamed class (or 6065 // enum), the first typedef-name declared by the declaration 6066 // to be that class type (or enum type) is used to denote the 6067 // class type (or enum type) for linkage purposes only. 6068 // We need to check whether the type was declared in the declaration. 6069 switch (D.getDeclSpec().getTypeSpecType()) { 6070 case TST_enum: 6071 case TST_struct: 6072 case TST_union: 6073 case TST_class: { 6074 TagDecl *tagFromDeclSpec = cast<TagDecl>(D.getDeclSpec().getRepAsDecl()); 6075 6076 // Do nothing if the tag is not anonymous or already has an 6077 // associated typedef (from an earlier typedef in this decl group). 6078 if (tagFromDeclSpec->getIdentifier()) break; 6079 if (tagFromDeclSpec->getTypedefForAnonDecl()) break; 6080 6081 // A well-formed anonymous tag must always be a TUK_Definition. 6082 assert(tagFromDeclSpec->isThisDeclarationADefinition()); 6083 6084 // The type must match the tag exactly; no qualifiers allowed. 6085 if (!Context.hasSameType(T, Context.getTagDeclType(tagFromDeclSpec))) 6086 break; 6087 6088 // Otherwise, set this is the anon-decl typedef for the tag. 6089 tagFromDeclSpec->setTypedefForAnonDecl(NewTD); 6090 break; 6091 } 6092 6093 default: 6094 break; 6095 } 6096 6097 return NewTD; 6098} 6099 6100 6101/// \brief Determine whether a tag with a given kind is acceptable 6102/// as a redeclaration of the given tag declaration. 6103/// 6104/// \returns true if the new tag kind is acceptable, false otherwise. 6105bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 6106 TagTypeKind NewTag, 6107 SourceLocation NewTagLoc, 6108 const IdentifierInfo &Name) { 6109 // C++ [dcl.type.elab]p3: 6110 // The class-key or enum keyword present in the 6111 // elaborated-type-specifier shall agree in kind with the 6112 // declaration to which the name in the elaborated-type-specifier 6113 // refers. This rule also applies to the form of 6114 // elaborated-type-specifier that declares a class-name or 6115 // friend class since it can be construed as referring to the 6116 // definition of the class. Thus, in any 6117 // elaborated-type-specifier, the enum keyword shall be used to 6118 // refer to an enumeration (7.2), the union class-key shall be 6119 // used to refer to a union (clause 9), and either the class or 6120 // struct class-key shall be used to refer to a class (clause 9) 6121 // declared using the class or struct class-key. 6122 TagTypeKind OldTag = Previous->getTagKind(); 6123 if (OldTag == NewTag) 6124 return true; 6125 6126 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 6127 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 6128 // Warn about the struct/class tag mismatch. 6129 bool isTemplate = false; 6130 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 6131 isTemplate = Record->getDescribedClassTemplate(); 6132 6133 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 6134 << (NewTag == TTK_Class) 6135 << isTemplate << &Name 6136 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 6137 OldTag == TTK_Class? "class" : "struct"); 6138 Diag(Previous->getLocation(), diag::note_previous_use); 6139 return true; 6140 } 6141 return false; 6142} 6143 6144/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 6145/// former case, Name will be non-null. In the later case, Name will be null. 6146/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 6147/// reference/declaration/definition of a tag. 6148Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 6149 SourceLocation KWLoc, CXXScopeSpec &SS, 6150 IdentifierInfo *Name, SourceLocation NameLoc, 6151 AttributeList *Attr, AccessSpecifier AS, 6152 MultiTemplateParamsArg TemplateParameterLists, 6153 bool &OwnedDecl, bool &IsDependent, 6154 bool ScopedEnum, bool ScopedEnumUsesClassTag, 6155 TypeResult UnderlyingType) { 6156 // If this is not a definition, it must have a name. 6157 assert((Name != 0 || TUK == TUK_Definition) && 6158 "Nameless record must be a definition!"); 6159 assert(TemplateParameterLists.size() == 0 || TUK != TUK_Reference); 6160 6161 OwnedDecl = false; 6162 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 6163 6164 // FIXME: Check explicit specializations more carefully. 6165 bool isExplicitSpecialization = false; 6166 bool Invalid = false; 6167 6168 // We only need to do this matching if we have template parameters 6169 // or a scope specifier, which also conveniently avoids this work 6170 // for non-C++ cases. 6171 if (TemplateParameterLists.size() > 0 || 6172 (SS.isNotEmpty() && TUK != TUK_Reference)) { 6173 if (TemplateParameterList *TemplateParams 6174 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 6175 TemplateParameterLists.get(), 6176 TemplateParameterLists.size(), 6177 TUK == TUK_Friend, 6178 isExplicitSpecialization, 6179 Invalid)) { 6180 if (TemplateParams->size() > 0) { 6181 // This is a declaration or definition of a class template (which may 6182 // be a member of another template). 6183 6184 if (Invalid) 6185 return 0; 6186 6187 OwnedDecl = false; 6188 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 6189 SS, Name, NameLoc, Attr, 6190 TemplateParams, AS, 6191 TemplateParameterLists.size() - 1, 6192 (TemplateParameterList**) TemplateParameterLists.release()); 6193 return Result.get(); 6194 } else { 6195 // The "template<>" header is extraneous. 6196 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 6197 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 6198 isExplicitSpecialization = true; 6199 } 6200 } 6201 } 6202 6203 // Figure out the underlying type if this a enum declaration. We need to do 6204 // this early, because it's needed to detect if this is an incompatible 6205 // redeclaration. 6206 llvm::PointerUnion<const Type*, TypeSourceInfo*> EnumUnderlying; 6207 6208 if (Kind == TTK_Enum) { 6209 if (UnderlyingType.isInvalid() || (!UnderlyingType.get() && ScopedEnum)) 6210 // No underlying type explicitly specified, or we failed to parse the 6211 // type, default to int. 6212 EnumUnderlying = Context.IntTy.getTypePtr(); 6213 else if (UnderlyingType.get()) { 6214 // C++0x 7.2p2: The type-specifier-seq of an enum-base shall name an 6215 // integral type; any cv-qualification is ignored. 6216 TypeSourceInfo *TI = 0; 6217 QualType T = GetTypeFromParser(UnderlyingType.get(), &TI); 6218 EnumUnderlying = TI; 6219 6220 SourceLocation UnderlyingLoc = TI->getTypeLoc().getBeginLoc(); 6221 6222 if (!T->isDependentType() && !T->isIntegralType(Context)) { 6223 Diag(UnderlyingLoc, diag::err_enum_invalid_underlying) 6224 << T; 6225 // Recover by falling back to int. 6226 EnumUnderlying = Context.IntTy.getTypePtr(); 6227 } 6228 6229 if (DiagnoseUnexpandedParameterPack(UnderlyingLoc, TI, 6230 UPPC_FixedUnderlyingType)) 6231 EnumUnderlying = Context.IntTy.getTypePtr(); 6232 6233 } else if (getLangOptions().Microsoft) 6234 // Microsoft enums are always of int type. 6235 EnumUnderlying = Context.IntTy.getTypePtr(); 6236 } 6237 6238 DeclContext *SearchDC = CurContext; 6239 DeclContext *DC = CurContext; 6240 bool isStdBadAlloc = false; 6241 6242 RedeclarationKind Redecl = ForRedeclaration; 6243 if (TUK == TUK_Friend || TUK == TUK_Reference) 6244 Redecl = NotForRedeclaration; 6245 6246 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 6247 6248 if (Name && SS.isNotEmpty()) { 6249 // We have a nested-name tag ('struct foo::bar'). 6250 6251 // Check for invalid 'foo::'. 6252 if (SS.isInvalid()) { 6253 Name = 0; 6254 goto CreateNewDecl; 6255 } 6256 6257 // If this is a friend or a reference to a class in a dependent 6258 // context, don't try to make a decl for it. 6259 if (TUK == TUK_Friend || TUK == TUK_Reference) { 6260 DC = computeDeclContext(SS, false); 6261 if (!DC) { 6262 IsDependent = true; 6263 return 0; 6264 } 6265 } else { 6266 DC = computeDeclContext(SS, true); 6267 if (!DC) { 6268 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 6269 << SS.getRange(); 6270 return 0; 6271 } 6272 } 6273 6274 if (RequireCompleteDeclContext(SS, DC)) 6275 return 0; 6276 6277 SearchDC = DC; 6278 // Look-up name inside 'foo::'. 6279 LookupQualifiedName(Previous, DC); 6280 6281 if (Previous.isAmbiguous()) 6282 return 0; 6283 6284 if (Previous.empty()) { 6285 // Name lookup did not find anything. However, if the 6286 // nested-name-specifier refers to the current instantiation, 6287 // and that current instantiation has any dependent base 6288 // classes, we might find something at instantiation time: treat 6289 // this as a dependent elaborated-type-specifier. 6290 // But this only makes any sense for reference-like lookups. 6291 if (Previous.wasNotFoundInCurrentInstantiation() && 6292 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6293 IsDependent = true; 6294 return 0; 6295 } 6296 6297 // A tag 'foo::bar' must already exist. 6298 Diag(NameLoc, diag::err_not_tag_in_scope) 6299 << Kind << Name << DC << SS.getRange(); 6300 Name = 0; 6301 Invalid = true; 6302 goto CreateNewDecl; 6303 } 6304 } else if (Name) { 6305 // If this is a named struct, check to see if there was a previous forward 6306 // declaration or definition. 6307 // FIXME: We're looking into outer scopes here, even when we 6308 // shouldn't be. Doing so can result in ambiguities that we 6309 // shouldn't be diagnosing. 6310 LookupName(Previous, S); 6311 6312 // Note: there used to be some attempt at recovery here. 6313 if (Previous.isAmbiguous()) 6314 return 0; 6315 6316 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 6317 // FIXME: This makes sure that we ignore the contexts associated 6318 // with C structs, unions, and enums when looking for a matching 6319 // tag declaration or definition. See the similar lookup tweak 6320 // in Sema::LookupName; is there a better way to deal with this? 6321 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 6322 SearchDC = SearchDC->getParent(); 6323 } 6324 } else if (S->isFunctionPrototypeScope()) { 6325 // If this is an enum declaration in function prototype scope, set its 6326 // initial context to the translation unit. 6327 SearchDC = Context.getTranslationUnitDecl(); 6328 } 6329 6330 if (Previous.isSingleResult() && 6331 Previous.getFoundDecl()->isTemplateParameter()) { 6332 // Maybe we will complain about the shadowed template parameter. 6333 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 6334 // Just pretend that we didn't see the previous declaration. 6335 Previous.clear(); 6336 } 6337 6338 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 6339 DC->Equals(getStdNamespace()) && Name->isStr("bad_alloc")) { 6340 // This is a declaration of or a reference to "std::bad_alloc". 6341 isStdBadAlloc = true; 6342 6343 if (Previous.empty() && StdBadAlloc) { 6344 // std::bad_alloc has been implicitly declared (but made invisible to 6345 // name lookup). Fill in this implicit declaration as the previous 6346 // declaration, so that the declarations get chained appropriately. 6347 Previous.addDecl(getStdBadAlloc()); 6348 } 6349 } 6350 6351 // If we didn't find a previous declaration, and this is a reference 6352 // (or friend reference), move to the correct scope. In C++, we 6353 // also need to do a redeclaration lookup there, just in case 6354 // there's a shadow friend decl. 6355 if (Name && Previous.empty() && 6356 (TUK == TUK_Reference || TUK == TUK_Friend)) { 6357 if (Invalid) goto CreateNewDecl; 6358 assert(SS.isEmpty()); 6359 6360 if (TUK == TUK_Reference) { 6361 // C++ [basic.scope.pdecl]p5: 6362 // -- for an elaborated-type-specifier of the form 6363 // 6364 // class-key identifier 6365 // 6366 // if the elaborated-type-specifier is used in the 6367 // decl-specifier-seq or parameter-declaration-clause of a 6368 // function defined in namespace scope, the identifier is 6369 // declared as a class-name in the namespace that contains 6370 // the declaration; otherwise, except as a friend 6371 // declaration, the identifier is declared in the smallest 6372 // non-class, non-function-prototype scope that contains the 6373 // declaration. 6374 // 6375 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 6376 // C structs and unions. 6377 // 6378 // It is an error in C++ to declare (rather than define) an enum 6379 // type, including via an elaborated type specifier. We'll 6380 // diagnose that later; for now, declare the enum in the same 6381 // scope as we would have picked for any other tag type. 6382 // 6383 // GNU C also supports this behavior as part of its incomplete 6384 // enum types extension, while GNU C++ does not. 6385 // 6386 // Find the context where we'll be declaring the tag. 6387 // FIXME: We would like to maintain the current DeclContext as the 6388 // lexical context, 6389 while (SearchDC->isRecord() || SearchDC->isTransparentContext()) 6390 SearchDC = SearchDC->getParent(); 6391 6392 // Find the scope where we'll be declaring the tag. 6393 while (S->isClassScope() || 6394 (getLangOptions().CPlusPlus && 6395 S->isFunctionPrototypeScope()) || 6396 ((S->getFlags() & Scope::DeclScope) == 0) || 6397 (S->getEntity() && 6398 ((DeclContext *)S->getEntity())->isTransparentContext())) 6399 S = S->getParent(); 6400 } else { 6401 assert(TUK == TUK_Friend); 6402 // C++ [namespace.memdef]p3: 6403 // If a friend declaration in a non-local class first declares a 6404 // class or function, the friend class or function is a member of 6405 // the innermost enclosing namespace. 6406 SearchDC = SearchDC->getEnclosingNamespaceContext(); 6407 } 6408 6409 // In C++, we need to do a redeclaration lookup to properly 6410 // diagnose some problems. 6411 if (getLangOptions().CPlusPlus) { 6412 Previous.setRedeclarationKind(ForRedeclaration); 6413 LookupQualifiedName(Previous, SearchDC); 6414 } 6415 } 6416 6417 if (!Previous.empty()) { 6418 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 6419 6420 // It's okay to have a tag decl in the same scope as a typedef 6421 // which hides a tag decl in the same scope. Finding this 6422 // insanity with a redeclaration lookup can only actually happen 6423 // in C++. 6424 // 6425 // This is also okay for elaborated-type-specifiers, which is 6426 // technically forbidden by the current standard but which is 6427 // okay according to the likely resolution of an open issue; 6428 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 6429 if (getLangOptions().CPlusPlus) { 6430 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 6431 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 6432 TagDecl *Tag = TT->getDecl(); 6433 if (Tag->getDeclName() == Name && 6434 Tag->getDeclContext()->getRedeclContext() 6435 ->Equals(TD->getDeclContext()->getRedeclContext())) { 6436 PrevDecl = Tag; 6437 Previous.clear(); 6438 Previous.addDecl(Tag); 6439 Previous.resolveKind(); 6440 } 6441 } 6442 } 6443 } 6444 6445 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 6446 // If this is a use of a previous tag, or if the tag is already declared 6447 // in the same scope (so that the definition/declaration completes or 6448 // rementions the tag), reuse the decl. 6449 if (TUK == TUK_Reference || TUK == TUK_Friend || 6450 isDeclInScope(PrevDecl, SearchDC, S, isExplicitSpecialization)) { 6451 // Make sure that this wasn't declared as an enum and now used as a 6452 // struct or something similar. 6453 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 6454 bool SafeToContinue 6455 = (PrevTagDecl->getTagKind() != TTK_Enum && 6456 Kind != TTK_Enum); 6457 if (SafeToContinue) 6458 Diag(KWLoc, diag::err_use_with_wrong_tag) 6459 << Name 6460 << FixItHint::CreateReplacement(SourceRange(KWLoc), 6461 PrevTagDecl->getKindName()); 6462 else 6463 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 6464 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6465 6466 if (SafeToContinue) 6467 Kind = PrevTagDecl->getTagKind(); 6468 else { 6469 // Recover by making this an anonymous redefinition. 6470 Name = 0; 6471 Previous.clear(); 6472 Invalid = true; 6473 } 6474 } 6475 6476 if (Kind == TTK_Enum && PrevTagDecl->getTagKind() == TTK_Enum) { 6477 const EnumDecl *PrevEnum = cast<EnumDecl>(PrevTagDecl); 6478 6479 // All conflicts with previous declarations are recovered by 6480 // returning the previous declaration. 6481 if (ScopedEnum != PrevEnum->isScoped()) { 6482 Diag(KWLoc, diag::err_enum_redeclare_scoped_mismatch) 6483 << PrevEnum->isScoped(); 6484 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6485 return PrevTagDecl; 6486 } 6487 else if (EnumUnderlying && PrevEnum->isFixed()) { 6488 QualType T; 6489 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6490 T = TI->getType(); 6491 else 6492 T = QualType(EnumUnderlying.get<const Type*>(), 0); 6493 6494 if (!Context.hasSameUnqualifiedType(T, PrevEnum->getIntegerType())) { 6495 Diag(NameLoc.isValid() ? NameLoc : KWLoc, 6496 diag::err_enum_redeclare_type_mismatch) 6497 << T 6498 << PrevEnum->getIntegerType(); 6499 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6500 return PrevTagDecl; 6501 } 6502 } 6503 else if (!EnumUnderlying.isNull() != PrevEnum->isFixed()) { 6504 Diag(KWLoc, diag::err_enum_redeclare_fixed_mismatch) 6505 << PrevEnum->isFixed(); 6506 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 6507 return PrevTagDecl; 6508 } 6509 } 6510 6511 if (!Invalid) { 6512 // If this is a use, just return the declaration we found. 6513 6514 // FIXME: In the future, return a variant or some other clue 6515 // for the consumer of this Decl to know it doesn't own it. 6516 // For our current ASTs this shouldn't be a problem, but will 6517 // need to be changed with DeclGroups. 6518 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 6519 TUK == TUK_Friend) 6520 return PrevTagDecl; 6521 6522 // Diagnose attempts to redefine a tag. 6523 if (TUK == TUK_Definition) { 6524 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 6525 // If we're defining a specialization and the previous definition 6526 // is from an implicit instantiation, don't emit an error 6527 // here; we'll catch this in the general case below. 6528 if (!isExplicitSpecialization || 6529 !isa<CXXRecordDecl>(Def) || 6530 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 6531 == TSK_ExplicitSpecialization) { 6532 Diag(NameLoc, diag::err_redefinition) << Name; 6533 Diag(Def->getLocation(), diag::note_previous_definition); 6534 // If this is a redefinition, recover by making this 6535 // struct be anonymous, which will make any later 6536 // references get the previous definition. 6537 Name = 0; 6538 Previous.clear(); 6539 Invalid = true; 6540 } 6541 } else { 6542 // If the type is currently being defined, complain 6543 // about a nested redefinition. 6544 const TagType *Tag 6545 = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 6546 if (Tag->isBeingDefined()) { 6547 Diag(NameLoc, diag::err_nested_redefinition) << Name; 6548 Diag(PrevTagDecl->getLocation(), 6549 diag::note_previous_definition); 6550 Name = 0; 6551 Previous.clear(); 6552 Invalid = true; 6553 } 6554 } 6555 6556 // Okay, this is definition of a previously declared or referenced 6557 // tag PrevDecl. We're going to create a new Decl for it. 6558 } 6559 } 6560 // If we get here we have (another) forward declaration or we 6561 // have a definition. Just create a new decl. 6562 6563 } else { 6564 // If we get here, this is a definition of a new tag type in a nested 6565 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 6566 // new decl/type. We set PrevDecl to NULL so that the entities 6567 // have distinct types. 6568 Previous.clear(); 6569 } 6570 // If we get here, we're going to create a new Decl. If PrevDecl 6571 // is non-NULL, it's a definition of the tag declared by 6572 // PrevDecl. If it's NULL, we have a new definition. 6573 6574 6575 // Otherwise, PrevDecl is not a tag, but was found with tag 6576 // lookup. This is only actually possible in C++, where a few 6577 // things like templates still live in the tag namespace. 6578 } else { 6579 assert(getLangOptions().CPlusPlus); 6580 6581 // Use a better diagnostic if an elaborated-type-specifier 6582 // found the wrong kind of type on the first 6583 // (non-redeclaration) lookup. 6584 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 6585 !Previous.isForRedeclaration()) { 6586 unsigned Kind = 0; 6587 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 6588 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 6589 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 6590 Diag(PrevDecl->getLocation(), diag::note_declared_at); 6591 Invalid = true; 6592 6593 // Otherwise, only diagnose if the declaration is in scope. 6594 } else if (!isDeclInScope(PrevDecl, SearchDC, S, 6595 isExplicitSpecialization)) { 6596 // do nothing 6597 6598 // Diagnose implicit declarations introduced by elaborated types. 6599 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 6600 unsigned Kind = 0; 6601 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 6602 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 6603 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 6604 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 6605 Invalid = true; 6606 6607 // Otherwise it's a declaration. Call out a particularly common 6608 // case here. 6609 } else if (isa<TypedefDecl>(PrevDecl)) { 6610 Diag(NameLoc, diag::err_tag_definition_of_typedef) 6611 << Name 6612 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 6613 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 6614 Invalid = true; 6615 6616 // Otherwise, diagnose. 6617 } else { 6618 // The tag name clashes with something else in the target scope, 6619 // issue an error and recover by making this tag be anonymous. 6620 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 6621 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6622 Name = 0; 6623 Invalid = true; 6624 } 6625 6626 // The existing declaration isn't relevant to us; we're in a 6627 // new scope, so clear out the previous declaration. 6628 Previous.clear(); 6629 } 6630 } 6631 6632CreateNewDecl: 6633 6634 TagDecl *PrevDecl = 0; 6635 if (Previous.isSingleResult()) 6636 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 6637 6638 // If there is an identifier, use the location of the identifier as the 6639 // location of the decl, otherwise use the location of the struct/union 6640 // keyword. 6641 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 6642 6643 // Otherwise, create a new declaration. If there is a previous 6644 // declaration of the same entity, the two will be linked via 6645 // PrevDecl. 6646 TagDecl *New; 6647 6648 bool IsForwardReference = false; 6649 if (Kind == TTK_Enum) { 6650 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6651 // enum X { A, B, C } D; D should chain to X. 6652 New = EnumDecl::Create(Context, SearchDC, KWLoc, Loc, Name, 6653 cast_or_null<EnumDecl>(PrevDecl), ScopedEnum, 6654 ScopedEnumUsesClassTag, !EnumUnderlying.isNull()); 6655 // If this is an undefined enum, warn. 6656 if (TUK != TUK_Definition && !Invalid) { 6657 TagDecl *Def; 6658 if (getLangOptions().CPlusPlus0x && cast<EnumDecl>(New)->isFixed()) { 6659 // C++0x: 7.2p2: opaque-enum-declaration. 6660 // Conflicts are diagnosed above. Do nothing. 6661 } 6662 else if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 6663 Diag(Loc, diag::ext_forward_ref_enum_def) 6664 << New; 6665 Diag(Def->getLocation(), diag::note_previous_definition); 6666 } else { 6667 unsigned DiagID = diag::ext_forward_ref_enum; 6668 if (getLangOptions().Microsoft) 6669 DiagID = diag::ext_ms_forward_ref_enum; 6670 else if (getLangOptions().CPlusPlus) 6671 DiagID = diag::err_forward_ref_enum; 6672 Diag(Loc, DiagID); 6673 6674 // If this is a forward-declared reference to an enumeration, make a 6675 // note of it; we won't actually be introducing the declaration into 6676 // the declaration context. 6677 if (TUK == TUK_Reference) 6678 IsForwardReference = true; 6679 } 6680 } 6681 6682 if (EnumUnderlying) { 6683 EnumDecl *ED = cast<EnumDecl>(New); 6684 if (TypeSourceInfo *TI = EnumUnderlying.dyn_cast<TypeSourceInfo*>()) 6685 ED->setIntegerTypeSourceInfo(TI); 6686 else 6687 ED->setIntegerType(QualType(EnumUnderlying.get<const Type*>(), 0)); 6688 ED->setPromotionType(ED->getIntegerType()); 6689 } 6690 6691 } else { 6692 // struct/union/class 6693 6694 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 6695 // struct X { int A; } D; D should chain to X. 6696 if (getLangOptions().CPlusPlus) { 6697 // FIXME: Look for a way to use RecordDecl for simple structs. 6698 New = CXXRecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 6699 cast_or_null<CXXRecordDecl>(PrevDecl)); 6700 6701 if (isStdBadAlloc && (!StdBadAlloc || getStdBadAlloc()->isImplicit())) 6702 StdBadAlloc = cast<CXXRecordDecl>(New); 6703 } else 6704 New = RecordDecl::Create(Context, Kind, SearchDC, KWLoc, Loc, Name, 6705 cast_or_null<RecordDecl>(PrevDecl)); 6706 } 6707 6708 // Maybe add qualifier info. 6709 if (SS.isNotEmpty()) { 6710 if (SS.isSet()) { 6711 New->setQualifierInfo(SS.getWithLocInContext(Context)); 6712 if (TemplateParameterLists.size() > 0) { 6713 New->setTemplateParameterListsInfo(Context, 6714 TemplateParameterLists.size(), 6715 (TemplateParameterList**) TemplateParameterLists.release()); 6716 } 6717 } 6718 else 6719 Invalid = true; 6720 } 6721 6722 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 6723 // Add alignment attributes if necessary; these attributes are checked when 6724 // the ASTContext lays out the structure. 6725 // 6726 // It is important for implementing the correct semantics that this 6727 // happen here (in act on tag decl). The #pragma pack stack is 6728 // maintained as a result of parser callbacks which can occur at 6729 // many points during the parsing of a struct declaration (because 6730 // the #pragma tokens are effectively skipped over during the 6731 // parsing of the struct). 6732 AddAlignmentAttributesForRecord(RD); 6733 } 6734 6735 // If this is a specialization of a member class (of a class template), 6736 // check the specialization. 6737 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 6738 Invalid = true; 6739 6740 if (Invalid) 6741 New->setInvalidDecl(); 6742 6743 if (Attr) 6744 ProcessDeclAttributeList(S, New, Attr); 6745 6746 // If we're declaring or defining a tag in function prototype scope 6747 // in C, note that this type can only be used within the function. 6748 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 6749 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 6750 6751 // Set the lexical context. If the tag has a C++ scope specifier, the 6752 // lexical context will be different from the semantic context. 6753 New->setLexicalDeclContext(CurContext); 6754 6755 // Mark this as a friend decl if applicable. 6756 if (TUK == TUK_Friend) 6757 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 6758 6759 // Set the access specifier. 6760 if (!Invalid && SearchDC->isRecord()) 6761 SetMemberAccessSpecifier(New, PrevDecl, AS); 6762 6763 if (TUK == TUK_Definition) 6764 New->startDefinition(); 6765 6766 // If this has an identifier, add it to the scope stack. 6767 if (TUK == TUK_Friend) { 6768 // We might be replacing an existing declaration in the lookup tables; 6769 // if so, borrow its access specifier. 6770 if (PrevDecl) 6771 New->setAccess(PrevDecl->getAccess()); 6772 6773 DeclContext *DC = New->getDeclContext()->getRedeclContext(); 6774 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6775 if (Name) // can be null along some error paths 6776 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 6777 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 6778 } else if (Name) { 6779 S = getNonFieldDeclScope(S); 6780 PushOnScopeChains(New, S, !IsForwardReference); 6781 if (IsForwardReference) 6782 SearchDC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 6783 6784 } else { 6785 CurContext->addDecl(New); 6786 } 6787 6788 // If this is the C FILE type, notify the AST context. 6789 if (IdentifierInfo *II = New->getIdentifier()) 6790 if (!New->isInvalidDecl() && 6791 New->getDeclContext()->getRedeclContext()->isTranslationUnit() && 6792 II->isStr("FILE")) 6793 Context.setFILEDecl(New); 6794 6795 OwnedDecl = true; 6796 return New; 6797} 6798 6799void Sema::ActOnTagStartDefinition(Scope *S, Decl *TagD) { 6800 AdjustDeclIfTemplate(TagD); 6801 TagDecl *Tag = cast<TagDecl>(TagD); 6802 6803 // Enter the tag context. 6804 PushDeclContext(S, Tag); 6805} 6806 6807void Sema::ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagD, 6808 SourceLocation FinalLoc, 6809 SourceLocation LBraceLoc) { 6810 AdjustDeclIfTemplate(TagD); 6811 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD); 6812 6813 FieldCollector->StartClass(); 6814 6815 if (!Record->getIdentifier()) 6816 return; 6817 6818 if (FinalLoc.isValid()) 6819 Record->addAttr(new (Context) FinalAttr(FinalLoc, Context)); 6820 6821 // C++ [class]p2: 6822 // [...] The class-name is also inserted into the scope of the 6823 // class itself; this is known as the injected-class-name. For 6824 // purposes of access checking, the injected-class-name is treated 6825 // as if it were a public member name. 6826 CXXRecordDecl *InjectedClassName 6827 = CXXRecordDecl::Create(Context, Record->getTagKind(), CurContext, 6828 Record->getLocStart(), Record->getLocation(), 6829 Record->getIdentifier(), 6830 /*PrevDecl=*/0, 6831 /*DelayTypeCreation=*/true); 6832 Context.getTypeDeclType(InjectedClassName, Record); 6833 InjectedClassName->setImplicit(); 6834 InjectedClassName->setAccess(AS_public); 6835 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 6836 InjectedClassName->setDescribedClassTemplate(Template); 6837 PushOnScopeChains(InjectedClassName, S); 6838 assert(InjectedClassName->isInjectedClassName() && 6839 "Broken injected-class-name"); 6840} 6841 6842void Sema::ActOnTagFinishDefinition(Scope *S, Decl *TagD, 6843 SourceLocation RBraceLoc) { 6844 AdjustDeclIfTemplate(TagD); 6845 TagDecl *Tag = cast<TagDecl>(TagD); 6846 Tag->setRBraceLoc(RBraceLoc); 6847 6848 if (isa<CXXRecordDecl>(Tag)) 6849 FieldCollector->FinishClass(); 6850 6851 // Exit this scope of this tag's definition. 6852 PopDeclContext(); 6853 6854 // Notify the consumer that we've defined a tag. 6855 Consumer.HandleTagDeclDefinition(Tag); 6856} 6857 6858void Sema::ActOnTagDefinitionError(Scope *S, Decl *TagD) { 6859 AdjustDeclIfTemplate(TagD); 6860 TagDecl *Tag = cast<TagDecl>(TagD); 6861 Tag->setInvalidDecl(); 6862 6863 // We're undoing ActOnTagStartDefinition here, not 6864 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 6865 // the FieldCollector. 6866 6867 PopDeclContext(); 6868} 6869 6870// Note that FieldName may be null for anonymous bitfields. 6871bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 6872 QualType FieldTy, const Expr *BitWidth, 6873 bool *ZeroWidth) { 6874 // Default to true; that shouldn't confuse checks for emptiness 6875 if (ZeroWidth) 6876 *ZeroWidth = true; 6877 6878 // C99 6.7.2.1p4 - verify the field type. 6879 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 6880 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 6881 // Handle incomplete types with specific error. 6882 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 6883 return true; 6884 if (FieldName) 6885 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 6886 << FieldName << FieldTy << BitWidth->getSourceRange(); 6887 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 6888 << FieldTy << BitWidth->getSourceRange(); 6889 } else if (DiagnoseUnexpandedParameterPack(const_cast<Expr *>(BitWidth), 6890 UPPC_BitFieldWidth)) 6891 return true; 6892 6893 // If the bit-width is type- or value-dependent, don't try to check 6894 // it now. 6895 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 6896 return false; 6897 6898 llvm::APSInt Value; 6899 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 6900 return true; 6901 6902 if (Value != 0 && ZeroWidth) 6903 *ZeroWidth = false; 6904 6905 // Zero-width bitfield is ok for anonymous field. 6906 if (Value == 0 && FieldName) 6907 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 6908 6909 if (Value.isSigned() && Value.isNegative()) { 6910 if (FieldName) 6911 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 6912 << FieldName << Value.toString(10); 6913 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 6914 << Value.toString(10); 6915 } 6916 6917 if (!FieldTy->isDependentType()) { 6918 uint64_t TypeSize = Context.getTypeSize(FieldTy); 6919 if (Value.getZExtValue() > TypeSize) { 6920 if (!getLangOptions().CPlusPlus) { 6921 if (FieldName) 6922 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 6923 << FieldName << (unsigned)Value.getZExtValue() 6924 << (unsigned)TypeSize; 6925 6926 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 6927 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6928 } 6929 6930 if (FieldName) 6931 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 6932 << FieldName << (unsigned)Value.getZExtValue() 6933 << (unsigned)TypeSize; 6934 else 6935 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 6936 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 6937 } 6938 } 6939 6940 return false; 6941} 6942 6943/// ActOnField - Each field of a struct/union/class is passed into this in order 6944/// to create a FieldDecl object for it. 6945Decl *Sema::ActOnField(Scope *S, Decl *TagD, 6946 SourceLocation DeclStart, 6947 Declarator &D, ExprTy *BitfieldWidth) { 6948 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD), 6949 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 6950 AS_public); 6951 return Res; 6952} 6953 6954/// HandleField - Analyze a field of a C struct or a C++ data member. 6955/// 6956FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 6957 SourceLocation DeclStart, 6958 Declarator &D, Expr *BitWidth, 6959 AccessSpecifier AS) { 6960 IdentifierInfo *II = D.getIdentifier(); 6961 SourceLocation Loc = DeclStart; 6962 if (II) Loc = D.getIdentifierLoc(); 6963 6964 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6965 QualType T = TInfo->getType(); 6966 if (getLangOptions().CPlusPlus) { 6967 CheckExtraCXXDefaultArguments(D); 6968 6969 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo, 6970 UPPC_DataMemberType)) { 6971 D.setInvalidType(); 6972 T = Context.IntTy; 6973 TInfo = Context.getTrivialTypeSourceInfo(T, Loc); 6974 } 6975 } 6976 6977 DiagnoseFunctionSpecifiers(D); 6978 6979 if (D.getDeclSpec().isThreadSpecified()) 6980 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 6981 6982 // Check to see if this name was declared as a member previously 6983 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration); 6984 LookupName(Previous, S); 6985 assert((Previous.empty() || Previous.isOverloadedResult() || 6986 Previous.isSingleResult()) 6987 && "Lookup of member name should be either overloaded, single or null"); 6988 6989 // If the name is overloaded then get any declaration else get the single result 6990 NamedDecl *PrevDecl = Previous.isOverloadedResult() ? 6991 Previous.getRepresentativeDecl() : Previous.getAsSingle<NamedDecl>(); 6992 6993 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6994 // Maybe we will complain about the shadowed template parameter. 6995 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 6996 // Just pretend that we didn't see the previous declaration. 6997 PrevDecl = 0; 6998 } 6999 7000 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 7001 PrevDecl = 0; 7002 7003 bool Mutable 7004 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 7005 SourceLocation TSSL = D.getSourceRange().getBegin(); 7006 FieldDecl *NewFD 7007 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 7008 AS, PrevDecl, &D); 7009 7010 if (NewFD->isInvalidDecl()) 7011 Record->setInvalidDecl(); 7012 7013 if (NewFD->isInvalidDecl() && PrevDecl) { 7014 // Don't introduce NewFD into scope; there's already something 7015 // with the same name in the same scope. 7016 } else if (II) { 7017 PushOnScopeChains(NewFD, S); 7018 } else 7019 Record->addDecl(NewFD); 7020 7021 return NewFD; 7022} 7023 7024/// \brief Build a new FieldDecl and check its well-formedness. 7025/// 7026/// This routine builds a new FieldDecl given the fields name, type, 7027/// record, etc. \p PrevDecl should refer to any previous declaration 7028/// with the same name and in the same scope as the field to be 7029/// created. 7030/// 7031/// \returns a new FieldDecl. 7032/// 7033/// \todo The Declarator argument is a hack. It will be removed once 7034FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 7035 TypeSourceInfo *TInfo, 7036 RecordDecl *Record, SourceLocation Loc, 7037 bool Mutable, Expr *BitWidth, 7038 SourceLocation TSSL, 7039 AccessSpecifier AS, NamedDecl *PrevDecl, 7040 Declarator *D) { 7041 IdentifierInfo *II = Name.getAsIdentifierInfo(); 7042 bool InvalidDecl = false; 7043 if (D) InvalidDecl = D->isInvalidType(); 7044 7045 // If we receive a broken type, recover by assuming 'int' and 7046 // marking this declaration as invalid. 7047 if (T.isNull()) { 7048 InvalidDecl = true; 7049 T = Context.IntTy; 7050 } 7051 7052 QualType EltTy = Context.getBaseElementType(T); 7053 if (!EltTy->isDependentType() && 7054 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) { 7055 // Fields of incomplete type force their record to be invalid. 7056 Record->setInvalidDecl(); 7057 InvalidDecl = true; 7058 } 7059 7060 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7061 // than a variably modified type. 7062 if (!InvalidDecl && T->isVariablyModifiedType()) { 7063 bool SizeIsNegative; 7064 llvm::APSInt Oversized; 7065 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 7066 SizeIsNegative, 7067 Oversized); 7068 if (!FixedTy.isNull()) { 7069 Diag(Loc, diag::warn_illegal_constant_array_size); 7070 T = FixedTy; 7071 } else { 7072 if (SizeIsNegative) 7073 Diag(Loc, diag::err_typecheck_negative_array_size); 7074 else if (Oversized.getBoolValue()) 7075 Diag(Loc, diag::err_array_too_large) 7076 << Oversized.toString(10); 7077 else 7078 Diag(Loc, diag::err_typecheck_field_variable_size); 7079 InvalidDecl = true; 7080 } 7081 } 7082 7083 // Fields can not have abstract class types 7084 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 7085 diag::err_abstract_type_in_decl, 7086 AbstractFieldType)) 7087 InvalidDecl = true; 7088 7089 bool ZeroWidth = false; 7090 // If this is declared as a bit-field, check the bit-field. 7091 if (!InvalidDecl && BitWidth && 7092 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 7093 InvalidDecl = true; 7094 BitWidth = 0; 7095 ZeroWidth = false; 7096 } 7097 7098 // Check that 'mutable' is consistent with the type of the declaration. 7099 if (!InvalidDecl && Mutable) { 7100 unsigned DiagID = 0; 7101 if (T->isReferenceType()) 7102 DiagID = diag::err_mutable_reference; 7103 else if (T.isConstQualified()) 7104 DiagID = diag::err_mutable_const; 7105 7106 if (DiagID) { 7107 SourceLocation ErrLoc = Loc; 7108 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 7109 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 7110 Diag(ErrLoc, DiagID); 7111 Mutable = false; 7112 InvalidDecl = true; 7113 } 7114 } 7115 7116 FieldDecl *NewFD = FieldDecl::Create(Context, Record, TSSL, Loc, II, T, TInfo, 7117 BitWidth, Mutable); 7118 if (InvalidDecl) 7119 NewFD->setInvalidDecl(); 7120 7121 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 7122 Diag(Loc, diag::err_duplicate_member) << II; 7123 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7124 NewFD->setInvalidDecl(); 7125 } 7126 7127 if (!InvalidDecl && getLangOptions().CPlusPlus) { 7128 if (Record->isUnion()) { 7129 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7130 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7131 if (RDecl->getDefinition()) { 7132 // C++ [class.union]p1: An object of a class with a non-trivial 7133 // constructor, a non-trivial copy constructor, a non-trivial 7134 // destructor, or a non-trivial copy assignment operator 7135 // cannot be a member of a union, nor can an array of such 7136 // objects. 7137 // TODO: C++0x alters this restriction significantly. 7138 if (CheckNontrivialField(NewFD)) 7139 NewFD->setInvalidDecl(); 7140 } 7141 } 7142 7143 // C++ [class.union]p1: If a union contains a member of reference type, 7144 // the program is ill-formed. 7145 if (EltTy->isReferenceType()) { 7146 Diag(NewFD->getLocation(), diag::err_union_member_of_reference_type) 7147 << NewFD->getDeclName() << EltTy; 7148 NewFD->setInvalidDecl(); 7149 } 7150 } 7151 } 7152 7153 // FIXME: We need to pass in the attributes given an AST 7154 // representation, not a parser representation. 7155 if (D) 7156 // FIXME: What to pass instead of TUScope? 7157 ProcessDeclAttributes(TUScope, NewFD, *D); 7158 7159 if (T.isObjCGCWeak()) 7160 Diag(Loc, diag::warn_attribute_weak_on_field); 7161 7162 NewFD->setAccess(AS); 7163 return NewFD; 7164} 7165 7166bool Sema::CheckNontrivialField(FieldDecl *FD) { 7167 assert(FD); 7168 assert(getLangOptions().CPlusPlus && "valid check only for C++"); 7169 7170 if (FD->isInvalidDecl()) 7171 return true; 7172 7173 QualType EltTy = Context.getBaseElementType(FD->getType()); 7174 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 7175 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 7176 if (RDecl->getDefinition()) { 7177 // We check for copy constructors before constructors 7178 // because otherwise we'll never get complaints about 7179 // copy constructors. 7180 7181 CXXSpecialMember member = CXXInvalid; 7182 if (!RDecl->hasTrivialCopyConstructor()) 7183 member = CXXCopyConstructor; 7184 else if (!RDecl->hasTrivialConstructor()) 7185 member = CXXConstructor; 7186 else if (!RDecl->hasTrivialCopyAssignment()) 7187 member = CXXCopyAssignment; 7188 else if (!RDecl->hasTrivialDestructor()) 7189 member = CXXDestructor; 7190 7191 if (member != CXXInvalid) { 7192 Diag(FD->getLocation(), diag::err_illegal_union_or_anon_struct_member) 7193 << (int)FD->getParent()->isUnion() << FD->getDeclName() << member; 7194 DiagnoseNontrivial(RT, member); 7195 return true; 7196 } 7197 } 7198 } 7199 7200 return false; 7201} 7202 7203/// DiagnoseNontrivial - Given that a class has a non-trivial 7204/// special member, figure out why. 7205void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 7206 QualType QT(T, 0U); 7207 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 7208 7209 // Check whether the member was user-declared. 7210 switch (member) { 7211 case CXXInvalid: 7212 break; 7213 7214 case CXXConstructor: 7215 if (RD->hasUserDeclaredConstructor()) { 7216 typedef CXXRecordDecl::ctor_iterator ctor_iter; 7217 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 7218 const FunctionDecl *body = 0; 7219 ci->hasBody(body); 7220 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 7221 SourceLocation CtorLoc = ci->getLocation(); 7222 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7223 return; 7224 } 7225 } 7226 7227 assert(0 && "found no user-declared constructors"); 7228 return; 7229 } 7230 break; 7231 7232 case CXXCopyConstructor: 7233 if (RD->hasUserDeclaredCopyConstructor()) { 7234 SourceLocation CtorLoc = 7235 RD->getCopyConstructor(Context, 0)->getLocation(); 7236 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7237 return; 7238 } 7239 break; 7240 7241 case CXXCopyAssignment: 7242 if (RD->hasUserDeclaredCopyAssignment()) { 7243 // FIXME: this should use the location of the copy 7244 // assignment, not the type. 7245 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 7246 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 7247 return; 7248 } 7249 break; 7250 7251 case CXXDestructor: 7252 if (RD->hasUserDeclaredDestructor()) { 7253 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 7254 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 7255 return; 7256 } 7257 break; 7258 } 7259 7260 typedef CXXRecordDecl::base_class_iterator base_iter; 7261 7262 // Virtual bases and members inhibit trivial copying/construction, 7263 // but not trivial destruction. 7264 if (member != CXXDestructor) { 7265 // Check for virtual bases. vbases includes indirect virtual bases, 7266 // so we just iterate through the direct bases. 7267 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 7268 if (bi->isVirtual()) { 7269 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7270 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 7271 return; 7272 } 7273 7274 // Check for virtual methods. 7275 typedef CXXRecordDecl::method_iterator meth_iter; 7276 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 7277 ++mi) { 7278 if (mi->isVirtual()) { 7279 SourceLocation MLoc = mi->getSourceRange().getBegin(); 7280 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 7281 return; 7282 } 7283 } 7284 } 7285 7286 bool (CXXRecordDecl::*hasTrivial)() const; 7287 switch (member) { 7288 case CXXConstructor: 7289 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 7290 case CXXCopyConstructor: 7291 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 7292 case CXXCopyAssignment: 7293 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 7294 case CXXDestructor: 7295 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 7296 default: 7297 assert(0 && "unexpected special member"); return; 7298 } 7299 7300 // Check for nontrivial bases (and recurse). 7301 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 7302 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 7303 assert(BaseRT && "Don't know how to handle dependent bases"); 7304 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 7305 if (!(BaseRecTy->*hasTrivial)()) { 7306 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 7307 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 7308 DiagnoseNontrivial(BaseRT, member); 7309 return; 7310 } 7311 } 7312 7313 // Check for nontrivial members (and recurse). 7314 typedef RecordDecl::field_iterator field_iter; 7315 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 7316 ++fi) { 7317 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 7318 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 7319 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 7320 7321 if (!(EltRD->*hasTrivial)()) { 7322 SourceLocation FLoc = (*fi)->getLocation(); 7323 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 7324 DiagnoseNontrivial(EltRT, member); 7325 return; 7326 } 7327 } 7328 } 7329 7330 assert(0 && "found no explanation for non-trivial member"); 7331} 7332 7333/// TranslateIvarVisibility - Translate visibility from a token ID to an 7334/// AST enum value. 7335static ObjCIvarDecl::AccessControl 7336TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 7337 switch (ivarVisibility) { 7338 default: assert(0 && "Unknown visitibility kind"); 7339 case tok::objc_private: return ObjCIvarDecl::Private; 7340 case tok::objc_public: return ObjCIvarDecl::Public; 7341 case tok::objc_protected: return ObjCIvarDecl::Protected; 7342 case tok::objc_package: return ObjCIvarDecl::Package; 7343 } 7344} 7345 7346/// ActOnIvar - Each ivar field of an objective-c class is passed into this 7347/// in order to create an IvarDecl object for it. 7348Decl *Sema::ActOnIvar(Scope *S, 7349 SourceLocation DeclStart, 7350 Decl *IntfDecl, 7351 Declarator &D, ExprTy *BitfieldWidth, 7352 tok::ObjCKeywordKind Visibility) { 7353 7354 IdentifierInfo *II = D.getIdentifier(); 7355 Expr *BitWidth = (Expr*)BitfieldWidth; 7356 SourceLocation Loc = DeclStart; 7357 if (II) Loc = D.getIdentifierLoc(); 7358 7359 // FIXME: Unnamed fields can be handled in various different ways, for 7360 // example, unnamed unions inject all members into the struct namespace! 7361 7362 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 7363 QualType T = TInfo->getType(); 7364 7365 if (BitWidth) { 7366 // 6.7.2.1p3, 6.7.2.1p4 7367 if (VerifyBitField(Loc, II, T, BitWidth)) { 7368 D.setInvalidType(); 7369 BitWidth = 0; 7370 } 7371 } else { 7372 // Not a bitfield. 7373 7374 // validate II. 7375 7376 } 7377 if (T->isReferenceType()) { 7378 Diag(Loc, diag::err_ivar_reference_type); 7379 D.setInvalidType(); 7380 } 7381 // C99 6.7.2.1p8: A member of a structure or union may have any type other 7382 // than a variably modified type. 7383 else if (T->isVariablyModifiedType()) { 7384 Diag(Loc, diag::err_typecheck_ivar_variable_size); 7385 D.setInvalidType(); 7386 } 7387 7388 // Get the visibility (access control) for this ivar. 7389 ObjCIvarDecl::AccessControl ac = 7390 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 7391 : ObjCIvarDecl::None; 7392 // Must set ivar's DeclContext to its enclosing interface. 7393 ObjCContainerDecl *EnclosingDecl = cast<ObjCContainerDecl>(IntfDecl); 7394 ObjCContainerDecl *EnclosingContext; 7395 if (ObjCImplementationDecl *IMPDecl = 7396 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7397 if (!LangOpts.ObjCNonFragileABI2) { 7398 // Case of ivar declared in an implementation. Context is that of its class. 7399 EnclosingContext = IMPDecl->getClassInterface(); 7400 assert(EnclosingContext && "Implementation has no class interface!"); 7401 } 7402 else 7403 EnclosingContext = EnclosingDecl; 7404 } else { 7405 if (ObjCCategoryDecl *CDecl = 7406 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7407 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 7408 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 7409 return 0; 7410 } 7411 } 7412 EnclosingContext = EnclosingDecl; 7413 } 7414 7415 // Construct the decl. 7416 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext, 7417 DeclStart, Loc, II, T, 7418 TInfo, ac, (Expr *)BitfieldWidth); 7419 7420 if (II) { 7421 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 7422 ForRedeclaration); 7423 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 7424 && !isa<TagDecl>(PrevDecl)) { 7425 Diag(Loc, diag::err_duplicate_member) << II; 7426 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 7427 NewID->setInvalidDecl(); 7428 } 7429 } 7430 7431 // Process attributes attached to the ivar. 7432 ProcessDeclAttributes(S, NewID, D); 7433 7434 if (D.isInvalidType()) 7435 NewID->setInvalidDecl(); 7436 7437 if (II) { 7438 // FIXME: When interfaces are DeclContexts, we'll need to add 7439 // these to the interface. 7440 S->AddDecl(NewID); 7441 IdResolver.AddDecl(NewID); 7442 } 7443 7444 return NewID; 7445} 7446 7447/// ActOnLastBitfield - This routine handles synthesized bitfields rules for 7448/// class and class extensions. For every class @interface and class 7449/// extension @interface, if the last ivar is a bitfield of any type, 7450/// then add an implicit `char :0` ivar to the end of that interface. 7451void Sema::ActOnLastBitfield(SourceLocation DeclLoc, Decl *EnclosingDecl, 7452 llvm::SmallVectorImpl<Decl *> &AllIvarDecls) { 7453 if (!LangOpts.ObjCNonFragileABI2 || AllIvarDecls.empty()) 7454 return; 7455 7456 Decl *ivarDecl = AllIvarDecls[AllIvarDecls.size()-1]; 7457 ObjCIvarDecl *Ivar = cast<ObjCIvarDecl>(ivarDecl); 7458 7459 if (!Ivar->isBitField()) 7460 return; 7461 uint64_t BitFieldSize = 7462 Ivar->getBitWidth()->EvaluateAsInt(Context).getZExtValue(); 7463 if (BitFieldSize == 0) 7464 return; 7465 ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl); 7466 if (!ID) { 7467 if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7468 if (!CD->IsClassExtension()) 7469 return; 7470 } 7471 // No need to add this to end of @implementation. 7472 else 7473 return; 7474 } 7475 // All conditions are met. Add a new bitfield to the tail end of ivars. 7476 llvm::APInt Zero(Context.getTypeSize(Context.CharTy), 0); 7477 Expr * BW = IntegerLiteral::Create(Context, Zero, Context.CharTy, DeclLoc); 7478 7479 Ivar = ObjCIvarDecl::Create(Context, cast<ObjCContainerDecl>(EnclosingDecl), 7480 DeclLoc, DeclLoc, 0, 7481 Context.CharTy, 7482 Context.CreateTypeSourceInfo(Context.CharTy), 7483 ObjCIvarDecl::Private, BW, 7484 true); 7485 AllIvarDecls.push_back(Ivar); 7486} 7487 7488void Sema::ActOnFields(Scope* S, 7489 SourceLocation RecLoc, Decl *EnclosingDecl, 7490 Decl **Fields, unsigned NumFields, 7491 SourceLocation LBrac, SourceLocation RBrac, 7492 AttributeList *Attr) { 7493 assert(EnclosingDecl && "missing record or interface decl"); 7494 7495 // If the decl this is being inserted into is invalid, then it may be a 7496 // redeclaration or some other bogus case. Don't try to add fields to it. 7497 if (EnclosingDecl->isInvalidDecl()) { 7498 // FIXME: Deallocate fields? 7499 return; 7500 } 7501 7502 7503 // Verify that all the fields are okay. 7504 unsigned NumNamedMembers = 0; 7505 llvm::SmallVector<FieldDecl*, 32> RecFields; 7506 7507 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 7508 for (unsigned i = 0; i != NumFields; ++i) { 7509 FieldDecl *FD = cast<FieldDecl>(Fields[i]); 7510 7511 // Get the type for the field. 7512 const Type *FDTy = FD->getType().getTypePtr(); 7513 7514 if (!FD->isAnonymousStructOrUnion()) { 7515 // Remember all fields written by the user. 7516 RecFields.push_back(FD); 7517 } 7518 7519 // If the field is already invalid for some reason, don't emit more 7520 // diagnostics about it. 7521 if (FD->isInvalidDecl()) { 7522 EnclosingDecl->setInvalidDecl(); 7523 continue; 7524 } 7525 7526 // C99 6.7.2.1p2: 7527 // A structure or union shall not contain a member with 7528 // incomplete or function type (hence, a structure shall not 7529 // contain an instance of itself, but may contain a pointer to 7530 // an instance of itself), except that the last member of a 7531 // structure with more than one named member may have incomplete 7532 // array type; such a structure (and any union containing, 7533 // possibly recursively, a member that is such a structure) 7534 // shall not be a member of a structure or an element of an 7535 // array. 7536 if (FDTy->isFunctionType()) { 7537 // Field declared as a function. 7538 Diag(FD->getLocation(), diag::err_field_declared_as_function) 7539 << FD->getDeclName(); 7540 FD->setInvalidDecl(); 7541 EnclosingDecl->setInvalidDecl(); 7542 continue; 7543 } else if (FDTy->isIncompleteArrayType() && Record && 7544 ((i == NumFields - 1 && !Record->isUnion()) || 7545 ((getLangOptions().Microsoft || getLangOptions().CPlusPlus) && 7546 (i == NumFields - 1 || Record->isUnion())))) { 7547 // Flexible array member. 7548 // Microsoft and g++ is more permissive regarding flexible array. 7549 // It will accept flexible array in union and also 7550 // as the sole element of a struct/class. 7551 if (getLangOptions().Microsoft) { 7552 if (Record->isUnion()) 7553 Diag(FD->getLocation(), diag::ext_flexible_array_union_ms) 7554 << FD->getDeclName(); 7555 else if (NumFields == 1) 7556 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_ms) 7557 << FD->getDeclName() << Record->getTagKind(); 7558 } else if (getLangOptions().CPlusPlus) { 7559 if (Record->isUnion()) 7560 Diag(FD->getLocation(), diag::ext_flexible_array_union_gnu) 7561 << FD->getDeclName(); 7562 else if (NumFields == 1) 7563 Diag(FD->getLocation(), diag::ext_flexible_array_empty_aggregate_gnu) 7564 << FD->getDeclName() << Record->getTagKind(); 7565 } else if (NumNamedMembers < 1) { 7566 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 7567 << FD->getDeclName(); 7568 FD->setInvalidDecl(); 7569 EnclosingDecl->setInvalidDecl(); 7570 continue; 7571 } 7572 if (!FD->getType()->isDependentType() && 7573 !Context.getBaseElementType(FD->getType())->isPODType()) { 7574 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 7575 << FD->getDeclName() << FD->getType(); 7576 FD->setInvalidDecl(); 7577 EnclosingDecl->setInvalidDecl(); 7578 continue; 7579 } 7580 // Okay, we have a legal flexible array member at the end of the struct. 7581 if (Record) 7582 Record->setHasFlexibleArrayMember(true); 7583 } else if (!FDTy->isDependentType() && 7584 RequireCompleteType(FD->getLocation(), FD->getType(), 7585 diag::err_field_incomplete)) { 7586 // Incomplete type 7587 FD->setInvalidDecl(); 7588 EnclosingDecl->setInvalidDecl(); 7589 continue; 7590 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 7591 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 7592 // If this is a member of a union, then entire union becomes "flexible". 7593 if (Record && Record->isUnion()) { 7594 Record->setHasFlexibleArrayMember(true); 7595 } else { 7596 // If this is a struct/class and this is not the last element, reject 7597 // it. Note that GCC supports variable sized arrays in the middle of 7598 // structures. 7599 if (i != NumFields-1) 7600 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 7601 << FD->getDeclName() << FD->getType(); 7602 else { 7603 // We support flexible arrays at the end of structs in 7604 // other structs as an extension. 7605 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 7606 << FD->getDeclName(); 7607 if (Record) 7608 Record->setHasFlexibleArrayMember(true); 7609 } 7610 } 7611 } 7612 if (Record && FDTTy->getDecl()->hasObjectMember()) 7613 Record->setHasObjectMember(true); 7614 } else if (FDTy->isObjCObjectType()) { 7615 /// A field cannot be an Objective-c object 7616 Diag(FD->getLocation(), diag::err_statically_allocated_object); 7617 FD->setInvalidDecl(); 7618 EnclosingDecl->setInvalidDecl(); 7619 continue; 7620 } else if (getLangOptions().ObjC1 && 7621 getLangOptions().getGCMode() != LangOptions::NonGC && 7622 Record && 7623 (FD->getType()->isObjCObjectPointerType() || 7624 FD->getType().isObjCGCStrong())) 7625 Record->setHasObjectMember(true); 7626 else if (Context.getAsArrayType(FD->getType())) { 7627 QualType BaseType = Context.getBaseElementType(FD->getType()); 7628 if (Record && BaseType->isRecordType() && 7629 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 7630 Record->setHasObjectMember(true); 7631 } 7632 // Keep track of the number of named members. 7633 if (FD->getIdentifier()) 7634 ++NumNamedMembers; 7635 } 7636 7637 // Okay, we successfully defined 'Record'. 7638 if (Record) { 7639 bool Completed = false; 7640 if (CXXRecordDecl *CXXRecord = dyn_cast<CXXRecordDecl>(Record)) { 7641 if (!CXXRecord->isInvalidDecl()) { 7642 // Set access bits correctly on the directly-declared conversions. 7643 UnresolvedSetImpl *Convs = CXXRecord->getConversionFunctions(); 7644 for (UnresolvedSetIterator I = Convs->begin(), E = Convs->end(); 7645 I != E; ++I) 7646 Convs->setAccess(I, (*I)->getAccess()); 7647 7648 if (!CXXRecord->isDependentType()) { 7649 // Add any implicitly-declared members to this class. 7650 AddImplicitlyDeclaredMembersToClass(CXXRecord); 7651 7652 // If we have virtual base classes, we may end up finding multiple 7653 // final overriders for a given virtual function. Check for this 7654 // problem now. 7655 if (CXXRecord->getNumVBases()) { 7656 CXXFinalOverriderMap FinalOverriders; 7657 CXXRecord->getFinalOverriders(FinalOverriders); 7658 7659 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(), 7660 MEnd = FinalOverriders.end(); 7661 M != MEnd; ++M) { 7662 for (OverridingMethods::iterator SO = M->second.begin(), 7663 SOEnd = M->second.end(); 7664 SO != SOEnd; ++SO) { 7665 assert(SO->second.size() > 0 && 7666 "Virtual function without overridding functions?"); 7667 if (SO->second.size() == 1) 7668 continue; 7669 7670 // C++ [class.virtual]p2: 7671 // In a derived class, if a virtual member function of a base 7672 // class subobject has more than one final overrider the 7673 // program is ill-formed. 7674 Diag(Record->getLocation(), diag::err_multiple_final_overriders) 7675 << (NamedDecl *)M->first << Record; 7676 Diag(M->first->getLocation(), 7677 diag::note_overridden_virtual_function); 7678 for (OverridingMethods::overriding_iterator 7679 OM = SO->second.begin(), 7680 OMEnd = SO->second.end(); 7681 OM != OMEnd; ++OM) 7682 Diag(OM->Method->getLocation(), diag::note_final_overrider) 7683 << (NamedDecl *)M->first << OM->Method->getParent(); 7684 7685 Record->setInvalidDecl(); 7686 } 7687 } 7688 CXXRecord->completeDefinition(&FinalOverriders); 7689 Completed = true; 7690 } 7691 } 7692 } 7693 } 7694 7695 if (!Completed) 7696 Record->completeDefinition(); 7697 } else { 7698 ObjCIvarDecl **ClsFields = 7699 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 7700 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 7701 ID->setLocEnd(RBrac); 7702 // Add ivar's to class's DeclContext. 7703 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7704 ClsFields[i]->setLexicalDeclContext(ID); 7705 ID->addDecl(ClsFields[i]); 7706 } 7707 // Must enforce the rule that ivars in the base classes may not be 7708 // duplicates. 7709 if (ID->getSuperClass()) 7710 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 7711 } else if (ObjCImplementationDecl *IMPDecl = 7712 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 7713 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 7714 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 7715 // Ivar declared in @implementation never belongs to the implementation. 7716 // Only it is in implementation's lexical context. 7717 ClsFields[I]->setLexicalDeclContext(IMPDecl); 7718 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 7719 } else if (ObjCCategoryDecl *CDecl = 7720 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 7721 // case of ivars in class extension; all other cases have been 7722 // reported as errors elsewhere. 7723 // FIXME. Class extension does not have a LocEnd field. 7724 // CDecl->setLocEnd(RBrac); 7725 // Add ivar's to class extension's DeclContext. 7726 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 7727 ClsFields[i]->setLexicalDeclContext(CDecl); 7728 CDecl->addDecl(ClsFields[i]); 7729 } 7730 } 7731 } 7732 7733 if (Attr) 7734 ProcessDeclAttributeList(S, Record, Attr); 7735 7736 // If there's a #pragma GCC visibility in scope, and this isn't a subclass, 7737 // set the visibility of this record. 7738 if (Record && !Record->getDeclContext()->isRecord()) 7739 AddPushedVisibilityAttribute(Record); 7740} 7741 7742/// \brief Determine whether the given integral value is representable within 7743/// the given type T. 7744static bool isRepresentableIntegerValue(ASTContext &Context, 7745 llvm::APSInt &Value, 7746 QualType T) { 7747 assert(T->isIntegralType(Context) && "Integral type required!"); 7748 unsigned BitWidth = Context.getIntWidth(T); 7749 7750 if (Value.isUnsigned() || Value.isNonNegative()) { 7751 if (T->isSignedIntegerType()) 7752 --BitWidth; 7753 return Value.getActiveBits() <= BitWidth; 7754 } 7755 return Value.getMinSignedBits() <= BitWidth; 7756} 7757 7758// \brief Given an integral type, return the next larger integral type 7759// (or a NULL type of no such type exists). 7760static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 7761 // FIXME: Int128/UInt128 support, which also needs to be introduced into 7762 // enum checking below. 7763 assert(T->isIntegralType(Context) && "Integral type required!"); 7764 const unsigned NumTypes = 4; 7765 QualType SignedIntegralTypes[NumTypes] = { 7766 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 7767 }; 7768 QualType UnsignedIntegralTypes[NumTypes] = { 7769 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 7770 Context.UnsignedLongLongTy 7771 }; 7772 7773 unsigned BitWidth = Context.getTypeSize(T); 7774 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 7775 : UnsignedIntegralTypes; 7776 for (unsigned I = 0; I != NumTypes; ++I) 7777 if (Context.getTypeSize(Types[I]) > BitWidth) 7778 return Types[I]; 7779 7780 return QualType(); 7781} 7782 7783EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 7784 EnumConstantDecl *LastEnumConst, 7785 SourceLocation IdLoc, 7786 IdentifierInfo *Id, 7787 Expr *Val) { 7788 unsigned IntWidth = Context.Target.getIntWidth(); 7789 llvm::APSInt EnumVal(IntWidth); 7790 QualType EltTy; 7791 7792 if (Val && DiagnoseUnexpandedParameterPack(Val, UPPC_EnumeratorValue)) 7793 Val = 0; 7794 7795 if (Val) { 7796 if (Enum->isDependentType() || Val->isTypeDependent()) 7797 EltTy = Context.DependentTy; 7798 else { 7799 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 7800 SourceLocation ExpLoc; 7801 if (!Val->isValueDependent() && 7802 VerifyIntegerConstantExpression(Val, &EnumVal)) { 7803 Val = 0; 7804 } else { 7805 if (!getLangOptions().CPlusPlus) { 7806 // C99 6.7.2.2p2: 7807 // The expression that defines the value of an enumeration constant 7808 // shall be an integer constant expression that has a value 7809 // representable as an int. 7810 7811 // Complain if the value is not representable in an int. 7812 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 7813 Diag(IdLoc, diag::ext_enum_value_not_int) 7814 << EnumVal.toString(10) << Val->getSourceRange() 7815 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 7816 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 7817 // Force the type of the expression to 'int'. 7818 Val = ImpCastExprToType(Val, Context.IntTy, CK_IntegralCast).take(); 7819 } 7820 } 7821 7822 if (Enum->isFixed()) { 7823 EltTy = Enum->getIntegerType(); 7824 7825 // C++0x [dcl.enum]p5: 7826 // ... if the initializing value of an enumerator cannot be 7827 // represented by the underlying type, the program is ill-formed. 7828 if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7829 if (getLangOptions().Microsoft) { 7830 Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy; 7831 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 7832 } else 7833 Diag(IdLoc, diag::err_enumerator_too_large) 7834 << EltTy; 7835 } else 7836 Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).take(); 7837 } 7838 else { 7839 // C++0x [dcl.enum]p5: 7840 // If the underlying type is not fixed, the type of each enumerator 7841 // is the type of its initializing value: 7842 // - If an initializer is specified for an enumerator, the 7843 // initializing value has the same type as the expression. 7844 EltTy = Val->getType(); 7845 } 7846 } 7847 } 7848 } 7849 7850 if (!Val) { 7851 if (Enum->isDependentType()) 7852 EltTy = Context.DependentTy; 7853 else if (!LastEnumConst) { 7854 // C++0x [dcl.enum]p5: 7855 // If the underlying type is not fixed, the type of each enumerator 7856 // is the type of its initializing value: 7857 // - If no initializer is specified for the first enumerator, the 7858 // initializing value has an unspecified integral type. 7859 // 7860 // GCC uses 'int' for its unspecified integral type, as does 7861 // C99 6.7.2.2p3. 7862 if (Enum->isFixed()) { 7863 EltTy = Enum->getIntegerType(); 7864 } 7865 else { 7866 EltTy = Context.IntTy; 7867 } 7868 } else { 7869 // Assign the last value + 1. 7870 EnumVal = LastEnumConst->getInitVal(); 7871 ++EnumVal; 7872 EltTy = LastEnumConst->getType(); 7873 7874 // Check for overflow on increment. 7875 if (EnumVal < LastEnumConst->getInitVal()) { 7876 // C++0x [dcl.enum]p5: 7877 // If the underlying type is not fixed, the type of each enumerator 7878 // is the type of its initializing value: 7879 // 7880 // - Otherwise the type of the initializing value is the same as 7881 // the type of the initializing value of the preceding enumerator 7882 // unless the incremented value is not representable in that type, 7883 // in which case the type is an unspecified integral type 7884 // sufficient to contain the incremented value. If no such type 7885 // exists, the program is ill-formed. 7886 QualType T = getNextLargerIntegralType(Context, EltTy); 7887 if (T.isNull() || Enum->isFixed()) { 7888 // There is no integral type larger enough to represent this 7889 // value. Complain, then allow the value to wrap around. 7890 EnumVal = LastEnumConst->getInitVal(); 7891 EnumVal = EnumVal.zext(EnumVal.getBitWidth() * 2); 7892 ++EnumVal; 7893 if (Enum->isFixed()) 7894 // When the underlying type is fixed, this is ill-formed. 7895 Diag(IdLoc, diag::err_enumerator_wrapped) 7896 << EnumVal.toString(10) 7897 << EltTy; 7898 else 7899 Diag(IdLoc, diag::warn_enumerator_too_large) 7900 << EnumVal.toString(10); 7901 } else { 7902 EltTy = T; 7903 } 7904 7905 // Retrieve the last enumerator's value, extent that type to the 7906 // type that is supposed to be large enough to represent the incremented 7907 // value, then increment. 7908 EnumVal = LastEnumConst->getInitVal(); 7909 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7910 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7911 ++EnumVal; 7912 7913 // If we're not in C++, diagnose the overflow of enumerator values, 7914 // which in C99 means that the enumerator value is not representable in 7915 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 7916 // permits enumerator values that are representable in some larger 7917 // integral type. 7918 if (!getLangOptions().CPlusPlus && !T.isNull()) 7919 Diag(IdLoc, diag::warn_enum_value_overflow); 7920 } else if (!getLangOptions().CPlusPlus && 7921 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 7922 // Enforce C99 6.7.2.2p2 even when we compute the next value. 7923 Diag(IdLoc, diag::ext_enum_value_not_int) 7924 << EnumVal.toString(10) << 1; 7925 } 7926 } 7927 } 7928 7929 if (!EltTy->isDependentType()) { 7930 // Make the enumerator value match the signedness and size of the 7931 // enumerator's type. 7932 EnumVal = EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 7933 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 7934 } 7935 7936 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 7937 Val, EnumVal); 7938} 7939 7940 7941Decl *Sema::ActOnEnumConstant(Scope *S, Decl *theEnumDecl, Decl *lastEnumConst, 7942 SourceLocation IdLoc, IdentifierInfo *Id, 7943 AttributeList *Attr, 7944 SourceLocation EqualLoc, ExprTy *val) { 7945 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl); 7946 EnumConstantDecl *LastEnumConst = 7947 cast_or_null<EnumConstantDecl>(lastEnumConst); 7948 Expr *Val = static_cast<Expr*>(val); 7949 7950 // The scope passed in may not be a decl scope. Zip up the scope tree until 7951 // we find one that is. 7952 S = getNonFieldDeclScope(S); 7953 7954 // Verify that there isn't already something declared with this name in this 7955 // scope. 7956 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 7957 ForRedeclaration); 7958 if (PrevDecl && PrevDecl->isTemplateParameter()) { 7959 // Maybe we will complain about the shadowed template parameter. 7960 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 7961 // Just pretend that we didn't see the previous declaration. 7962 PrevDecl = 0; 7963 } 7964 7965 if (PrevDecl) { 7966 // When in C++, we may get a TagDecl with the same name; in this case the 7967 // enum constant will 'hide' the tag. 7968 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 7969 "Received TagDecl when not in C++!"); 7970 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 7971 if (isa<EnumConstantDecl>(PrevDecl)) 7972 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 7973 else 7974 Diag(IdLoc, diag::err_redefinition) << Id; 7975 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 7976 return 0; 7977 } 7978 } 7979 7980 // C++ [class.mem]p13: 7981 // If T is the name of a class, then each of the following shall have a 7982 // name different from T: 7983 // - every enumerator of every member of class T that is an enumerated 7984 // type 7985 if (CXXRecordDecl *Record 7986 = dyn_cast<CXXRecordDecl>( 7987 TheEnumDecl->getDeclContext()->getRedeclContext())) 7988 if (Record->getIdentifier() && Record->getIdentifier() == Id) 7989 Diag(IdLoc, diag::err_member_name_of_class) << Id; 7990 7991 EnumConstantDecl *New = 7992 CheckEnumConstant(TheEnumDecl, LastEnumConst, IdLoc, Id, Val); 7993 7994 if (New) { 7995 // Process attributes. 7996 if (Attr) ProcessDeclAttributeList(S, New, Attr); 7997 7998 // Register this decl in the current scope stack. 7999 New->setAccess(TheEnumDecl->getAccess()); 8000 PushOnScopeChains(New, S); 8001 } 8002 8003 return New; 8004} 8005 8006void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 8007 SourceLocation RBraceLoc, Decl *EnumDeclX, 8008 Decl **Elements, unsigned NumElements, 8009 Scope *S, AttributeList *Attr) { 8010 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX); 8011 QualType EnumType = Context.getTypeDeclType(Enum); 8012 8013 if (Attr) 8014 ProcessDeclAttributeList(S, Enum, Attr); 8015 8016 if (Enum->isDependentType()) { 8017 for (unsigned i = 0; i != NumElements; ++i) { 8018 EnumConstantDecl *ECD = 8019 cast_or_null<EnumConstantDecl>(Elements[i]); 8020 if (!ECD) continue; 8021 8022 ECD->setType(EnumType); 8023 } 8024 8025 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 8026 return; 8027 } 8028 8029 // TODO: If the result value doesn't fit in an int, it must be a long or long 8030 // long value. ISO C does not support this, but GCC does as an extension, 8031 // emit a warning. 8032 unsigned IntWidth = Context.Target.getIntWidth(); 8033 unsigned CharWidth = Context.Target.getCharWidth(); 8034 unsigned ShortWidth = Context.Target.getShortWidth(); 8035 8036 // Verify that all the values are okay, compute the size of the values, and 8037 // reverse the list. 8038 unsigned NumNegativeBits = 0; 8039 unsigned NumPositiveBits = 0; 8040 8041 // Keep track of whether all elements have type int. 8042 bool AllElementsInt = true; 8043 8044 for (unsigned i = 0; i != NumElements; ++i) { 8045 EnumConstantDecl *ECD = 8046 cast_or_null<EnumConstantDecl>(Elements[i]); 8047 if (!ECD) continue; // Already issued a diagnostic. 8048 8049 const llvm::APSInt &InitVal = ECD->getInitVal(); 8050 8051 // Keep track of the size of positive and negative values. 8052 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 8053 NumPositiveBits = std::max(NumPositiveBits, 8054 (unsigned)InitVal.getActiveBits()); 8055 else 8056 NumNegativeBits = std::max(NumNegativeBits, 8057 (unsigned)InitVal.getMinSignedBits()); 8058 8059 // Keep track of whether every enum element has type int (very commmon). 8060 if (AllElementsInt) 8061 AllElementsInt = ECD->getType() == Context.IntTy; 8062 } 8063 8064 // Figure out the type that should be used for this enum. 8065 QualType BestType; 8066 unsigned BestWidth; 8067 8068 // C++0x N3000 [conv.prom]p3: 8069 // An rvalue of an unscoped enumeration type whose underlying 8070 // type is not fixed can be converted to an rvalue of the first 8071 // of the following types that can represent all the values of 8072 // the enumeration: int, unsigned int, long int, unsigned long 8073 // int, long long int, or unsigned long long int. 8074 // C99 6.4.4.3p2: 8075 // An identifier declared as an enumeration constant has type int. 8076 // The C99 rule is modified by a gcc extension 8077 QualType BestPromotionType; 8078 8079 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 8080 // -fshort-enums is the equivalent to specifying the packed attribute on all 8081 // enum definitions. 8082 if (LangOpts.ShortEnums) 8083 Packed = true; 8084 8085 if (Enum->isFixed()) { 8086 BestType = BestPromotionType = Enum->getIntegerType(); 8087 // We don't need to set BestWidth, because BestType is going to be the type 8088 // of the enumerators, but we do anyway because otherwise some compilers 8089 // warn that it might be used uninitialized. 8090 BestWidth = CharWidth; 8091 } 8092 else if (NumNegativeBits) { 8093 // If there is a negative value, figure out the smallest integer type (of 8094 // int/long/longlong) that fits. 8095 // If it's packed, check also if it fits a char or a short. 8096 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 8097 BestType = Context.SignedCharTy; 8098 BestWidth = CharWidth; 8099 } else if (Packed && NumNegativeBits <= ShortWidth && 8100 NumPositiveBits < ShortWidth) { 8101 BestType = Context.ShortTy; 8102 BestWidth = ShortWidth; 8103 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 8104 BestType = Context.IntTy; 8105 BestWidth = IntWidth; 8106 } else { 8107 BestWidth = Context.Target.getLongWidth(); 8108 8109 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 8110 BestType = Context.LongTy; 8111 } else { 8112 BestWidth = Context.Target.getLongLongWidth(); 8113 8114 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 8115 Diag(Enum->getLocation(), diag::warn_enum_too_large); 8116 BestType = Context.LongLongTy; 8117 } 8118 } 8119 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 8120 } else { 8121 // If there is no negative value, figure out the smallest type that fits 8122 // all of the enumerator values. 8123 // If it's packed, check also if it fits a char or a short. 8124 if (Packed && NumPositiveBits <= CharWidth) { 8125 BestType = Context.UnsignedCharTy; 8126 BestPromotionType = Context.IntTy; 8127 BestWidth = CharWidth; 8128 } else if (Packed && NumPositiveBits <= ShortWidth) { 8129 BestType = Context.UnsignedShortTy; 8130 BestPromotionType = Context.IntTy; 8131 BestWidth = ShortWidth; 8132 } else if (NumPositiveBits <= IntWidth) { 8133 BestType = Context.UnsignedIntTy; 8134 BestWidth = IntWidth; 8135 BestPromotionType 8136 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8137 ? Context.UnsignedIntTy : Context.IntTy; 8138 } else if (NumPositiveBits <= 8139 (BestWidth = Context.Target.getLongWidth())) { 8140 BestType = Context.UnsignedLongTy; 8141 BestPromotionType 8142 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8143 ? Context.UnsignedLongTy : Context.LongTy; 8144 } else { 8145 BestWidth = Context.Target.getLongLongWidth(); 8146 assert(NumPositiveBits <= BestWidth && 8147 "How could an initializer get larger than ULL?"); 8148 BestType = Context.UnsignedLongLongTy; 8149 BestPromotionType 8150 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 8151 ? Context.UnsignedLongLongTy : Context.LongLongTy; 8152 } 8153 } 8154 8155 // Loop over all of the enumerator constants, changing their types to match 8156 // the type of the enum if needed. 8157 for (unsigned i = 0; i != NumElements; ++i) { 8158 EnumConstantDecl *ECD = cast_or_null<EnumConstantDecl>(Elements[i]); 8159 if (!ECD) continue; // Already issued a diagnostic. 8160 8161 // Standard C says the enumerators have int type, but we allow, as an 8162 // extension, the enumerators to be larger than int size. If each 8163 // enumerator value fits in an int, type it as an int, otherwise type it the 8164 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 8165 // that X has type 'int', not 'unsigned'. 8166 8167 // Determine whether the value fits into an int. 8168 llvm::APSInt InitVal = ECD->getInitVal(); 8169 8170 // If it fits into an integer type, force it. Otherwise force it to match 8171 // the enum decl type. 8172 QualType NewTy; 8173 unsigned NewWidth; 8174 bool NewSign; 8175 if (!getLangOptions().CPlusPlus && 8176 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 8177 NewTy = Context.IntTy; 8178 NewWidth = IntWidth; 8179 NewSign = true; 8180 } else if (ECD->getType() == BestType) { 8181 // Already the right type! 8182 if (getLangOptions().CPlusPlus) 8183 // C++ [dcl.enum]p4: Following the closing brace of an 8184 // enum-specifier, each enumerator has the type of its 8185 // enumeration. 8186 ECD->setType(EnumType); 8187 continue; 8188 } else { 8189 NewTy = BestType; 8190 NewWidth = BestWidth; 8191 NewSign = BestType->isSignedIntegerType(); 8192 } 8193 8194 // Adjust the APSInt value. 8195 InitVal = InitVal.extOrTrunc(NewWidth); 8196 InitVal.setIsSigned(NewSign); 8197 ECD->setInitVal(InitVal); 8198 8199 // Adjust the Expr initializer and type. 8200 if (ECD->getInitExpr() && 8201 !Context.hasSameType(NewTy, ECD->getInitExpr()->getType())) 8202 ECD->setInitExpr(ImplicitCastExpr::Create(Context, NewTy, 8203 CK_IntegralCast, 8204 ECD->getInitExpr(), 8205 /*base paths*/ 0, 8206 VK_RValue)); 8207 if (getLangOptions().CPlusPlus) 8208 // C++ [dcl.enum]p4: Following the closing brace of an 8209 // enum-specifier, each enumerator has the type of its 8210 // enumeration. 8211 ECD->setType(EnumType); 8212 else 8213 ECD->setType(NewTy); 8214 } 8215 8216 Enum->completeDefinition(BestType, BestPromotionType, 8217 NumPositiveBits, NumNegativeBits); 8218} 8219 8220Decl *Sema::ActOnFileScopeAsmDecl(Expr *expr, 8221 SourceLocation StartLoc, 8222 SourceLocation EndLoc) { 8223 StringLiteral *AsmString = cast<StringLiteral>(expr); 8224 8225 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 8226 AsmString, StartLoc, 8227 EndLoc); 8228 CurContext->addDecl(New); 8229 return New; 8230} 8231 8232void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 8233 SourceLocation PragmaLoc, 8234 SourceLocation NameLoc) { 8235 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 8236 8237 if (PrevDecl) { 8238 PrevDecl->addAttr(::new (Context) WeakAttr(PragmaLoc, Context)); 8239 } else { 8240 (void)WeakUndeclaredIdentifiers.insert( 8241 std::pair<IdentifierInfo*,WeakInfo> 8242 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 8243 } 8244} 8245 8246void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 8247 IdentifierInfo* AliasName, 8248 SourceLocation PragmaLoc, 8249 SourceLocation NameLoc, 8250 SourceLocation AliasNameLoc) { 8251 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 8252 LookupOrdinaryName); 8253 WeakInfo W = WeakInfo(Name, NameLoc); 8254 8255 if (PrevDecl) { 8256 if (!PrevDecl->hasAttr<AliasAttr>()) 8257 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 8258 DeclApplyPragmaWeak(TUScope, ND, W); 8259 } else { 8260 (void)WeakUndeclaredIdentifiers.insert( 8261 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 8262 } 8263} 8264