SemaDecl.cpp revision e126f73aaca758b4076d26ab25ef02ed99e9240b
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 "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/ParseDiagnostic.h" 26#include "clang/Parse/Template.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/Triple.h" 34#include <algorithm> 35#include <cstring> 36#include <functional> 37using namespace clang; 38 39/// getDeclName - Return a pretty name for the specified decl if possible, or 40/// an empty string if not. This is used for pretty crash reporting. 41std::string Sema::getDeclName(DeclPtrTy d) { 42 Decl *D = d.getAs<Decl>(); 43 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 44 return DN->getQualifiedNameAsString(); 45 return ""; 46} 47 48Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 49 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 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. 63Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 64 Scope *S, CXXScopeSpec *SS, 65 bool isClassName, 66 TypeTy *ObjectTypePtr) { 67 // Determine where we will perform name lookup. 68 DeclContext *LookupCtx = 0; 69 if (ObjectTypePtr) { 70 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 71 if (ObjectType->isRecordType()) 72 LookupCtx = computeDeclContext(ObjectType); 73 } else if (SS && SS->isNotEmpty()) { 74 LookupCtx = computeDeclContext(*SS, false); 75 76 if (!LookupCtx) { 77 if (isDependentScopeSpecifier(*SS)) { 78 // C++ [temp.res]p3: 79 // A qualified-id that refers to a type and in which the 80 // nested-name-specifier depends on a template-parameter (14.6.2) 81 // shall be prefixed by the keyword typename to indicate that the 82 // qualified-id denotes a type, forming an 83 // elaborated-type-specifier (7.1.5.3). 84 // 85 // We therefore do not perform any name lookup if the result would 86 // refer to a member of an unknown specialization. 87 if (!isClassName) 88 return 0; 89 90 // We know from the grammar that this name refers to a type, 91 // so build a dependent node to describe the type. 92 return CheckTypenameType(ETK_None, 93 (NestedNameSpecifier *)SS->getScopeRep(), II, 94 SourceLocation(), SS->getRange(), NameLoc 95 ).getAsOpaquePtr(); 96 } 97 98 return 0; 99 } 100 101 if (!LookupCtx->isDependentContext() && 102 RequireCompleteDeclContext(*SS, LookupCtx)) 103 return 0; 104 } 105 106 // FIXME: LookupNestedNameSpecifierName isn't the right kind of 107 // lookup for class-names. 108 LookupNameKind Kind = isClassName ? LookupNestedNameSpecifierName : 109 LookupOrdinaryName; 110 LookupResult Result(*this, &II, NameLoc, Kind); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::NotFoundInCurrentInstantiation: 136 case LookupResult::FoundOverloaded: 137 case LookupResult::FoundUnresolvedValue: 138 Result.suppressDiagnostics(); 139 return 0; 140 141 case LookupResult::Ambiguous: 142 // Recover from type-hiding ambiguities by hiding the type. We'll 143 // do the lookup again when looking for an object, and we can 144 // diagnose the error then. If we don't do this, then the error 145 // about hiding the type will be immediately followed by an error 146 // that only makes sense if the identifier was treated like a type. 147 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 148 Result.suppressDiagnostics(); 149 return 0; 150 } 151 152 // Look to see if we have a type anywhere in the list of results. 153 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 154 Res != ResEnd; ++Res) { 155 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 156 if (!IIDecl || 157 (*Res)->getLocation().getRawEncoding() < 158 IIDecl->getLocation().getRawEncoding()) 159 IIDecl = *Res; 160 } 161 } 162 163 if (!IIDecl) { 164 // None of the entities we found is a type, so there is no way 165 // to even assume that the result is a type. In this case, don't 166 // complain about the ambiguity. The parser will either try to 167 // perform this lookup again (e.g., as an object name), which 168 // will produce the ambiguity, or will complain that it expected 169 // a type name. 170 Result.suppressDiagnostics(); 171 return 0; 172 } 173 174 // We found a type within the ambiguous lookup; diagnose the 175 // ambiguity and then return that type. This might be the right 176 // answer, or it might not be, but it suppresses any attempt to 177 // perform the name lookup again. 178 break; 179 180 case LookupResult::Found: 181 IIDecl = Result.getFoundDecl(); 182 break; 183 } 184 185 assert(IIDecl && "Didn't find decl"); 186 187 QualType T; 188 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 189 DiagnoseUseOfDecl(IIDecl, NameLoc); 190 191 if (T.isNull()) 192 T = Context.getTypeDeclType(TD); 193 194 if (SS) 195 T = getElaboratedType(ETK_None, *SS, T); 196 197 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 198 T = Context.getObjCInterfaceType(IDecl); 199 } else { 200 // If it's not plausibly a type, suppress diagnostics. 201 Result.suppressDiagnostics(); 202 return 0; 203 } 204 205 return T.getAsOpaquePtr(); 206} 207 208/// isTagName() - This method is called *for error recovery purposes only* 209/// to determine if the specified name is a valid tag name ("struct foo"). If 210/// so, this returns the TST for the tag corresponding to it (TST_enum, 211/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 212/// where the user forgot to specify the tag. 213DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 214 // Do a tag name lookup in this scope. 215 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 216 LookupName(R, S, false); 217 R.suppressDiagnostics(); 218 if (R.getResultKind() == LookupResult::Found) 219 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 220 switch (TD->getTagKind()) { 221 default: return DeclSpec::TST_unspecified; 222 case TTK_Struct: return DeclSpec::TST_struct; 223 case TTK_Union: return DeclSpec::TST_union; 224 case TTK_Class: return DeclSpec::TST_class; 225 case TTK_Enum: return DeclSpec::TST_enum; 226 } 227 } 228 229 return DeclSpec::TST_unspecified; 230} 231 232bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 233 SourceLocation IILoc, 234 Scope *S, 235 CXXScopeSpec *SS, 236 TypeTy *&SuggestedType) { 237 // We don't have anything to suggest (yet). 238 SuggestedType = 0; 239 240 // There may have been a typo in the name of the type. Look up typo 241 // results, in case we have something that we can suggest. 242 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 243 NotForRedeclaration); 244 245 if (DeclarationName Corrected = CorrectTypo(Lookup, S, SS, 0, 0, CTC_Type)) { 246 if (NamedDecl *Result = Lookup.getAsSingle<NamedDecl>()) { 247 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 248 !Result->isInvalidDecl()) { 249 // We found a similarly-named type or interface; suggest that. 250 if (!SS || !SS->isSet()) 251 Diag(IILoc, diag::err_unknown_typename_suggest) 252 << &II << Lookup.getLookupName() 253 << FixItHint::CreateReplacement(SourceRange(IILoc), 254 Result->getNameAsString()); 255 else if (DeclContext *DC = computeDeclContext(*SS, false)) 256 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 257 << &II << DC << Lookup.getLookupName() << SS->getRange() 258 << FixItHint::CreateReplacement(SourceRange(IILoc), 259 Result->getNameAsString()); 260 else 261 llvm_unreachable("could not have corrected a typo here"); 262 263 Diag(Result->getLocation(), diag::note_previous_decl) 264 << Result->getDeclName(); 265 266 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 267 return true; 268 } 269 } else if (Lookup.empty()) { 270 // We corrected to a keyword. 271 // FIXME: Actually recover with the keyword we suggest, and emit a fix-it. 272 Diag(IILoc, diag::err_unknown_typename_suggest) 273 << &II << Corrected; 274 return true; 275 } 276 } 277 278 if (getLangOptions().CPlusPlus) { 279 // See if II is a class template that the user forgot to pass arguments to. 280 UnqualifiedId Name; 281 Name.setIdentifier(&II, IILoc); 282 CXXScopeSpec EmptySS; 283 TemplateTy TemplateResult; 284 bool MemberOfUnknownSpecialization; 285 if (isTemplateName(S, SS ? *SS : EmptySS, Name, 0, true, TemplateResult, 286 MemberOfUnknownSpecialization) == TNK_Type_template) { 287 TemplateName TplName = TemplateResult.getAsVal<TemplateName>(); 288 Diag(IILoc, diag::err_template_missing_args) << TplName; 289 if (TemplateDecl *TplDecl = TplName.getAsTemplateDecl()) { 290 Diag(TplDecl->getLocation(), diag::note_template_decl_here) 291 << TplDecl->getTemplateParameters()->getSourceRange(); 292 } 293 return true; 294 } 295 } 296 297 // FIXME: Should we move the logic that tries to recover from a missing tag 298 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 299 300 if (!SS || (!SS->isSet() && !SS->isInvalid())) 301 Diag(IILoc, diag::err_unknown_typename) << &II; 302 else if (DeclContext *DC = computeDeclContext(*SS, false)) 303 Diag(IILoc, diag::err_typename_nested_not_found) 304 << &II << DC << SS->getRange(); 305 else if (isDependentScopeSpecifier(*SS)) { 306 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 307 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 308 << SourceRange(SS->getRange().getBegin(), IILoc) 309 << FixItHint::CreateInsertion(SS->getRange().getBegin(), "typename "); 310 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 311 } else { 312 assert(SS && SS->isInvalid() && 313 "Invalid scope specifier has already been diagnosed"); 314 } 315 316 return true; 317} 318 319// Determines the context to return to after temporarily entering a 320// context. This depends in an unnecessarily complicated way on the 321// exact ordering of callbacks from the parser. 322DeclContext *Sema::getContainingDC(DeclContext *DC) { 323 324 // Functions defined inline within classes aren't parsed until we've 325 // finished parsing the top-level class, so the top-level class is 326 // the context we'll need to return to. 327 if (isa<FunctionDecl>(DC)) { 328 DC = DC->getLexicalParent(); 329 330 // A function not defined within a class will always return to its 331 // lexical context. 332 if (!isa<CXXRecordDecl>(DC)) 333 return DC; 334 335 // A C++ inline method/friend is parsed *after* the topmost class 336 // it was declared in is fully parsed ("complete"); the topmost 337 // class is the context we need to return to. 338 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 339 DC = RD; 340 341 // Return the declaration context of the topmost class the inline method is 342 // declared in. 343 return DC; 344 } 345 346 if (isa<ObjCMethodDecl>(DC)) 347 return Context.getTranslationUnitDecl(); 348 349 return DC->getLexicalParent(); 350} 351 352void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 353 assert(getContainingDC(DC) == CurContext && 354 "The next DeclContext should be lexically contained in the current one."); 355 CurContext = DC; 356 S->setEntity(DC); 357} 358 359void Sema::PopDeclContext() { 360 assert(CurContext && "DeclContext imbalance!"); 361 362 CurContext = getContainingDC(CurContext); 363} 364 365/// EnterDeclaratorContext - Used when we must lookup names in the context 366/// of a declarator's nested name specifier. 367/// 368void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 369 // C++0x [basic.lookup.unqual]p13: 370 // A name used in the definition of a static data member of class 371 // X (after the qualified-id of the static member) is looked up as 372 // if the name was used in a member function of X. 373 // C++0x [basic.lookup.unqual]p14: 374 // If a variable member of a namespace is defined outside of the 375 // scope of its namespace then any name used in the definition of 376 // the variable member (after the declarator-id) is looked up as 377 // if the definition of the variable member occurred in its 378 // namespace. 379 // Both of these imply that we should push a scope whose context 380 // is the semantic context of the declaration. We can't use 381 // PushDeclContext here because that context is not necessarily 382 // lexically contained in the current context. Fortunately, 383 // the containing scope should have the appropriate information. 384 385 assert(!S->getEntity() && "scope already has entity"); 386 387#ifndef NDEBUG 388 Scope *Ancestor = S->getParent(); 389 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 390 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 391#endif 392 393 CurContext = DC; 394 S->setEntity(DC); 395} 396 397void Sema::ExitDeclaratorContext(Scope *S) { 398 assert(S->getEntity() == CurContext && "Context imbalance!"); 399 400 // Switch back to the lexical context. The safety of this is 401 // enforced by an assert in EnterDeclaratorContext. 402 Scope *Ancestor = S->getParent(); 403 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 404 CurContext = (DeclContext*) Ancestor->getEntity(); 405 406 // We don't need to do anything with the scope, which is going to 407 // disappear. 408} 409 410/// \brief Determine whether we allow overloading of the function 411/// PrevDecl with another declaration. 412/// 413/// This routine determines whether overloading is possible, not 414/// whether some new function is actually an overload. It will return 415/// true in C++ (where we can always provide overloads) or, as an 416/// extension, in C when the previous function is already an 417/// overloaded function declaration or has the "overloadable" 418/// attribute. 419static bool AllowOverloadingOfFunction(LookupResult &Previous, 420 ASTContext &Context) { 421 if (Context.getLangOptions().CPlusPlus) 422 return true; 423 424 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 425 return true; 426 427 return (Previous.getResultKind() == LookupResult::Found 428 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 429} 430 431/// Add this decl to the scope shadowed decl chains. 432void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 433 // Move up the scope chain until we find the nearest enclosing 434 // non-transparent context. The declaration will be introduced into this 435 // scope. 436 while (S->getEntity() && 437 ((DeclContext *)S->getEntity())->isTransparentContext()) 438 S = S->getParent(); 439 440 // Add scoped declarations into their context, so that they can be 441 // found later. Declarations without a context won't be inserted 442 // into any context. 443 if (AddToContext) 444 CurContext->addDecl(D); 445 446 // Out-of-line definitions shouldn't be pushed into scope in C++. 447 // Out-of-line variable and function definitions shouldn't even in C. 448 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 449 D->isOutOfLine()) 450 return; 451 452 // Template instantiations should also not be pushed into scope. 453 if (isa<FunctionDecl>(D) && 454 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 455 return; 456 457 // If this replaces anything in the current scope, 458 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 459 IEnd = IdResolver.end(); 460 for (; I != IEnd; ++I) { 461 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 462 S->RemoveDecl(DeclPtrTy::make(*I)); 463 IdResolver.RemoveDecl(*I); 464 465 // Should only need to replace one decl. 466 break; 467 } 468 } 469 470 S->AddDecl(DeclPtrTy::make(D)); 471 IdResolver.AddDecl(D); 472} 473 474bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 475 return IdResolver.isDeclInScope(D, Ctx, Context, S); 476} 477 478static bool isOutOfScopePreviousDeclaration(NamedDecl *, 479 DeclContext*, 480 ASTContext&); 481 482/// Filters out lookup results that don't fall within the given scope 483/// as determined by isDeclInScope. 484static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 485 DeclContext *Ctx, Scope *S, 486 bool ConsiderLinkage) { 487 LookupResult::Filter F = R.makeFilter(); 488 while (F.hasNext()) { 489 NamedDecl *D = F.next(); 490 491 if (SemaRef.isDeclInScope(D, Ctx, S)) 492 continue; 493 494 if (ConsiderLinkage && 495 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 496 continue; 497 498 F.erase(); 499 } 500 501 F.done(); 502} 503 504static bool isUsingDecl(NamedDecl *D) { 505 return isa<UsingShadowDecl>(D) || 506 isa<UnresolvedUsingTypenameDecl>(D) || 507 isa<UnresolvedUsingValueDecl>(D); 508} 509 510/// Removes using shadow declarations from the lookup results. 511static void RemoveUsingDecls(LookupResult &R) { 512 LookupResult::Filter F = R.makeFilter(); 513 while (F.hasNext()) 514 if (isUsingDecl(F.next())) 515 F.erase(); 516 517 F.done(); 518} 519 520static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 521 if (D->isInvalidDecl()) 522 return false; 523 524 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 525 return false; 526 527 // White-list anything that isn't a local variable. 528 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 529 !D->getDeclContext()->isFunctionOrMethod()) 530 return false; 531 532 // Types of valid local variables should be complete, so this should succeed. 533 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 534 535 // White-list anything with an __attribute__((unused)) type. 536 QualType Ty = VD->getType(); 537 538 // Only look at the outermost level of typedef. 539 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 540 if (TT->getDecl()->hasAttr<UnusedAttr>()) 541 return false; 542 } 543 544 // If we failed to complete the type for some reason, or if the type is 545 // dependent, don't diagnose the variable. 546 if (Ty->isIncompleteType() || Ty->isDependentType()) 547 return false; 548 549 if (const TagType *TT = Ty->getAs<TagType>()) { 550 const TagDecl *Tag = TT->getDecl(); 551 if (Tag->hasAttr<UnusedAttr>()) 552 return false; 553 554 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 555 // FIXME: Checking for the presence of a user-declared constructor 556 // isn't completely accurate; we'd prefer to check that the initializer 557 // has no side effects. 558 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 559 return false; 560 } 561 } 562 563 // TODO: __attribute__((unused)) templates? 564 } 565 566 return true; 567} 568 569void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 570 if (!ShouldDiagnoseUnusedDecl(D)) 571 return; 572 573 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 574 Diag(D->getLocation(), diag::warn_unused_exception_param) 575 << D->getDeclName(); 576 else 577 Diag(D->getLocation(), diag::warn_unused_variable) 578 << D->getDeclName(); 579} 580 581void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 582 if (S->decl_empty()) return; 583 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 584 "Scope shouldn't contain decls!"); 585 586 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 587 I != E; ++I) { 588 Decl *TmpD = (*I).getAs<Decl>(); 589 assert(TmpD && "This decl didn't get pushed??"); 590 591 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 592 NamedDecl *D = cast<NamedDecl>(TmpD); 593 594 if (!D->getDeclName()) continue; 595 596 // Diagnose unused variables in this scope. 597 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 598 DiagnoseUnusedDecl(D); 599 600 // Remove this name from our lexical scope. 601 IdResolver.RemoveDecl(D); 602 } 603} 604 605/// \brief Look for an Objective-C class in the translation unit. 606/// 607/// \param Id The name of the Objective-C class we're looking for. If 608/// typo-correction fixes this name, the Id will be updated 609/// to the fixed name. 610/// 611/// \param IdLoc The location of the name in the translation unit. 612/// 613/// \param TypoCorrection If true, this routine will attempt typo correction 614/// if there is no class with the given name. 615/// 616/// \returns The declaration of the named Objective-C class, or NULL if the 617/// class could not be found. 618ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 619 SourceLocation IdLoc, 620 bool TypoCorrection) { 621 // The third "scope" argument is 0 since we aren't enabling lazy built-in 622 // creation from this context. 623 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 624 625 if (!IDecl && TypoCorrection) { 626 // Perform typo correction at the given location, but only if we 627 // find an Objective-C class name. 628 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 629 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 630 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 631 Diag(IdLoc, diag::err_undef_interface_suggest) 632 << Id << IDecl->getDeclName() 633 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 634 Diag(IDecl->getLocation(), diag::note_previous_decl) 635 << IDecl->getDeclName(); 636 637 Id = IDecl->getIdentifier(); 638 } 639 } 640 641 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 642} 643 644/// getNonFieldDeclScope - Retrieves the innermost scope, starting 645/// from S, where a non-field would be declared. This routine copes 646/// with the difference between C and C++ scoping rules in structs and 647/// unions. For example, the following code is well-formed in C but 648/// ill-formed in C++: 649/// @code 650/// struct S6 { 651/// enum { BAR } e; 652/// }; 653/// 654/// void test_S6() { 655/// struct S6 a; 656/// a.e = BAR; 657/// } 658/// @endcode 659/// For the declaration of BAR, this routine will return a different 660/// scope. The scope S will be the scope of the unnamed enumeration 661/// within S6. In C++, this routine will return the scope associated 662/// with S6, because the enumeration's scope is a transparent 663/// context but structures can contain non-field names. In C, this 664/// routine will return the translation unit scope, since the 665/// enumeration's scope is a transparent context and structures cannot 666/// contain non-field names. 667Scope *Sema::getNonFieldDeclScope(Scope *S) { 668 while (((S->getFlags() & Scope::DeclScope) == 0) || 669 (S->getEntity() && 670 ((DeclContext *)S->getEntity())->isTransparentContext()) || 671 (S->isClassScope() && !getLangOptions().CPlusPlus)) 672 S = S->getParent(); 673 return S; 674} 675 676void Sema::InitBuiltinVaListType() { 677 if (!Context.getBuiltinVaListType().isNull()) 678 return; 679 680 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 681 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 682 LookupOrdinaryName, ForRedeclaration); 683 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 684 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 685} 686 687/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 688/// file scope. lazily create a decl for it. ForRedeclaration is true 689/// if we're creating this built-in in anticipation of redeclaring the 690/// built-in. 691NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 692 Scope *S, bool ForRedeclaration, 693 SourceLocation Loc) { 694 Builtin::ID BID = (Builtin::ID)bid; 695 696 if (Context.BuiltinInfo.hasVAListUse(BID)) 697 InitBuiltinVaListType(); 698 699 ASTContext::GetBuiltinTypeError Error; 700 QualType R = Context.GetBuiltinType(BID, Error); 701 switch (Error) { 702 case ASTContext::GE_None: 703 // Okay 704 break; 705 706 case ASTContext::GE_Missing_stdio: 707 if (ForRedeclaration) 708 Diag(Loc, diag::err_implicit_decl_requires_stdio) 709 << Context.BuiltinInfo.GetName(BID); 710 return 0; 711 712 case ASTContext::GE_Missing_setjmp: 713 if (ForRedeclaration) 714 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 715 << Context.BuiltinInfo.GetName(BID); 716 return 0; 717 } 718 719 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 720 Diag(Loc, diag::ext_implicit_lib_function_decl) 721 << Context.BuiltinInfo.GetName(BID) 722 << R; 723 if (Context.BuiltinInfo.getHeaderName(BID) && 724 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 725 != Diagnostic::Ignored) 726 Diag(Loc, diag::note_please_include_header) 727 << Context.BuiltinInfo.getHeaderName(BID) 728 << Context.BuiltinInfo.GetName(BID); 729 } 730 731 FunctionDecl *New = FunctionDecl::Create(Context, 732 Context.getTranslationUnitDecl(), 733 Loc, II, R, /*TInfo=*/0, 734 FunctionDecl::Extern, 735 FunctionDecl::None, false, 736 /*hasPrototype=*/true); 737 New->setImplicit(); 738 739 // Create Decl objects for each parameter, adding them to the 740 // FunctionDecl. 741 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 742 llvm::SmallVector<ParmVarDecl*, 16> Params; 743 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 744 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 745 FT->getArgType(i), /*TInfo=*/0, 746 VarDecl::None, VarDecl::None, 0)); 747 New->setParams(Params.data(), Params.size()); 748 } 749 750 AddKnownFunctionAttributes(New); 751 752 // TUScope is the translation-unit scope to insert this function into. 753 // FIXME: This is hideous. We need to teach PushOnScopeChains to 754 // relate Scopes to DeclContexts, and probably eliminate CurContext 755 // entirely, but we're not there yet. 756 DeclContext *SavedContext = CurContext; 757 CurContext = Context.getTranslationUnitDecl(); 758 PushOnScopeChains(New, TUScope); 759 CurContext = SavedContext; 760 return New; 761} 762 763/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 764/// same name and scope as a previous declaration 'Old'. Figure out 765/// how to resolve this situation, merging decls or emitting 766/// diagnostics as appropriate. If there was an error, set New to be invalid. 767/// 768void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 769 // If the new decl is known invalid already, don't bother doing any 770 // merging checks. 771 if (New->isInvalidDecl()) return; 772 773 // Allow multiple definitions for ObjC built-in typedefs. 774 // FIXME: Verify the underlying types are equivalent! 775 if (getLangOptions().ObjC1) { 776 const IdentifierInfo *TypeID = New->getIdentifier(); 777 switch (TypeID->getLength()) { 778 default: break; 779 case 2: 780 if (!TypeID->isStr("id")) 781 break; 782 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 783 // Install the built-in type for 'id', ignoring the current definition. 784 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 785 return; 786 case 5: 787 if (!TypeID->isStr("Class")) 788 break; 789 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 790 // Install the built-in type for 'Class', ignoring the current definition. 791 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 792 return; 793 case 3: 794 if (!TypeID->isStr("SEL")) 795 break; 796 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 797 // Install the built-in type for 'SEL', ignoring the current definition. 798 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 799 return; 800 case 8: 801 if (!TypeID->isStr("Protocol")) 802 break; 803 Context.setObjCProtoType(New->getUnderlyingType()); 804 return; 805 } 806 // Fall through - the typedef name was not a builtin type. 807 } 808 809 // Verify the old decl was also a type. 810 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 811 if (!Old) { 812 Diag(New->getLocation(), diag::err_redefinition_different_kind) 813 << New->getDeclName(); 814 815 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 816 if (OldD->getLocation().isValid()) 817 Diag(OldD->getLocation(), diag::note_previous_definition); 818 819 return New->setInvalidDecl(); 820 } 821 822 // If the old declaration is invalid, just give up here. 823 if (Old->isInvalidDecl()) 824 return New->setInvalidDecl(); 825 826 // Determine the "old" type we'll use for checking and diagnostics. 827 QualType OldType; 828 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 829 OldType = OldTypedef->getUnderlyingType(); 830 else 831 OldType = Context.getTypeDeclType(Old); 832 833 // If the typedef types are not identical, reject them in all languages and 834 // with any extensions enabled. 835 836 if (OldType != New->getUnderlyingType() && 837 Context.getCanonicalType(OldType) != 838 Context.getCanonicalType(New->getUnderlyingType())) { 839 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 840 << New->getUnderlyingType() << OldType; 841 if (Old->getLocation().isValid()) 842 Diag(Old->getLocation(), diag::note_previous_definition); 843 return New->setInvalidDecl(); 844 } 845 846 // The types match. Link up the redeclaration chain if the old 847 // declaration was a typedef. 848 // FIXME: this is a potential source of wierdness if the type 849 // spellings don't match exactly. 850 if (isa<TypedefDecl>(Old)) 851 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 852 853 if (getLangOptions().Microsoft) 854 return; 855 856 if (getLangOptions().CPlusPlus) { 857 // C++ [dcl.typedef]p2: 858 // In a given non-class scope, a typedef specifier can be used to 859 // redefine the name of any type declared in that scope to refer 860 // to the type to which it already refers. 861 if (!isa<CXXRecordDecl>(CurContext)) 862 return; 863 864 // C++0x [dcl.typedef]p4: 865 // In a given class scope, a typedef specifier can be used to redefine 866 // any class-name declared in that scope that is not also a typedef-name 867 // to refer to the type to which it already refers. 868 // 869 // This wording came in via DR424, which was a correction to the 870 // wording in DR56, which accidentally banned code like: 871 // 872 // struct S { 873 // typedef struct A { } A; 874 // }; 875 // 876 // in the C++03 standard. We implement the C++0x semantics, which 877 // allow the above but disallow 878 // 879 // struct S { 880 // typedef int I; 881 // typedef int I; 882 // }; 883 // 884 // since that was the intent of DR56. 885 if (!isa<TypedefDecl >(Old)) 886 return; 887 888 Diag(New->getLocation(), diag::err_redefinition) 889 << New->getDeclName(); 890 Diag(Old->getLocation(), diag::note_previous_definition); 891 return New->setInvalidDecl(); 892 } 893 894 // If we have a redefinition of a typedef in C, emit a warning. This warning 895 // is normally mapped to an error, but can be controlled with 896 // -Wtypedef-redefinition. If either the original or the redefinition is 897 // in a system header, don't emit this for compatibility with GCC. 898 if (getDiagnostics().getSuppressSystemWarnings() && 899 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 900 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 901 return; 902 903 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 904 << New->getDeclName(); 905 Diag(Old->getLocation(), diag::note_previous_definition); 906 return; 907} 908 909/// DeclhasAttr - returns true if decl Declaration already has the target 910/// attribute. 911static bool 912DeclHasAttr(const Decl *decl, const Attr *target) { 913 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 914 if (attr->getKind() == target->getKind()) 915 return true; 916 917 return false; 918} 919 920/// MergeAttributes - append attributes from the Old decl to the New one. 921static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 922 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 923 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 924 Attr *NewAttr = attr->clone(C); 925 NewAttr->setInherited(true); 926 New->addAttr(NewAttr); 927 } 928 } 929} 930 931/// Used in MergeFunctionDecl to keep track of function parameters in 932/// C. 933struct GNUCompatibleParamWarning { 934 ParmVarDecl *OldParm; 935 ParmVarDecl *NewParm; 936 QualType PromotedType; 937}; 938 939 940/// getSpecialMember - get the special member enum for a method. 941Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 942 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 943 if (Ctor->isCopyConstructor()) 944 return Sema::CXXCopyConstructor; 945 946 return Sema::CXXConstructor; 947 } 948 949 if (isa<CXXDestructorDecl>(MD)) 950 return Sema::CXXDestructor; 951 952 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 953 return Sema::CXXCopyAssignment; 954} 955 956/// canRedefineFunction - checks if a function can be redefined. Currently, 957/// only extern inline functions can be redefined, and even then only in 958/// GNU89 mode. 959static bool canRedefineFunction(const FunctionDecl *FD, 960 const LangOptions& LangOpts) { 961 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 962 FD->isInlineSpecified() && 963 FD->getStorageClass() == FunctionDecl::Extern); 964} 965 966/// MergeFunctionDecl - We just parsed a function 'New' from 967/// declarator D which has the same name and scope as a previous 968/// declaration 'Old'. Figure out how to resolve this situation, 969/// merging decls or emitting diagnostics as appropriate. 970/// 971/// In C++, New and Old must be declarations that are not 972/// overloaded. Use IsOverload to determine whether New and Old are 973/// overloaded, and to select the Old declaration that New should be 974/// merged with. 975/// 976/// Returns true if there was an error, false otherwise. 977bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 978 // Verify the old decl was also a function. 979 FunctionDecl *Old = 0; 980 if (FunctionTemplateDecl *OldFunctionTemplate 981 = dyn_cast<FunctionTemplateDecl>(OldD)) 982 Old = OldFunctionTemplate->getTemplatedDecl(); 983 else 984 Old = dyn_cast<FunctionDecl>(OldD); 985 if (!Old) { 986 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 987 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 988 Diag(Shadow->getTargetDecl()->getLocation(), 989 diag::note_using_decl_target); 990 Diag(Shadow->getUsingDecl()->getLocation(), 991 diag::note_using_decl) << 0; 992 return true; 993 } 994 995 Diag(New->getLocation(), diag::err_redefinition_different_kind) 996 << New->getDeclName(); 997 Diag(OldD->getLocation(), diag::note_previous_definition); 998 return true; 999 } 1000 1001 // Determine whether the previous declaration was a definition, 1002 // implicit declaration, or a declaration. 1003 diag::kind PrevDiag; 1004 if (Old->isThisDeclarationADefinition()) 1005 PrevDiag = diag::note_previous_definition; 1006 else if (Old->isImplicit()) 1007 PrevDiag = diag::note_previous_implicit_declaration; 1008 else 1009 PrevDiag = diag::note_previous_declaration; 1010 1011 QualType OldQType = Context.getCanonicalType(Old->getType()); 1012 QualType NewQType = Context.getCanonicalType(New->getType()); 1013 1014 // Don't complain about this if we're in GNU89 mode and the old function 1015 // is an extern inline function. 1016 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1017 New->getStorageClass() == FunctionDecl::Static && 1018 Old->getStorageClass() != FunctionDecl::Static && 1019 !canRedefineFunction(Old, getLangOptions())) { 1020 Diag(New->getLocation(), diag::err_static_non_static) 1021 << New; 1022 Diag(Old->getLocation(), PrevDiag); 1023 return true; 1024 } 1025 1026 // If a function is first declared with a calling convention, but is 1027 // later declared or defined without one, the second decl assumes the 1028 // calling convention of the first. 1029 // 1030 // For the new decl, we have to look at the NON-canonical type to tell the 1031 // difference between a function that really doesn't have a calling 1032 // convention and one that is declared cdecl. That's because in 1033 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1034 // because it is the default calling convention. 1035 // 1036 // Note also that we DO NOT return at this point, because we still have 1037 // other tests to run. 1038 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1039 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1040 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1041 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1042 if (OldTypeInfo.getCC() != CC_Default && 1043 NewTypeInfo.getCC() == CC_Default) { 1044 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1045 New->setType(NewQType); 1046 NewQType = Context.getCanonicalType(NewQType); 1047 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1048 NewTypeInfo.getCC())) { 1049 // Calling conventions really aren't compatible, so complain. 1050 Diag(New->getLocation(), diag::err_cconv_change) 1051 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1052 << (OldTypeInfo.getCC() == CC_Default) 1053 << (OldTypeInfo.getCC() == CC_Default ? "" : 1054 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1055 Diag(Old->getLocation(), diag::note_previous_declaration); 1056 return true; 1057 } 1058 1059 // FIXME: diagnose the other way around? 1060 if (OldType->getNoReturnAttr() && 1061 !NewType->getNoReturnAttr()) { 1062 NewQType = Context.getNoReturnType(NewQType); 1063 New->setType(NewQType); 1064 assert(NewQType.isCanonical()); 1065 } 1066 1067 if (getLangOptions().CPlusPlus) { 1068 // (C++98 13.1p2): 1069 // Certain function declarations cannot be overloaded: 1070 // -- Function declarations that differ only in the return type 1071 // cannot be overloaded. 1072 QualType OldReturnType 1073 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1074 QualType NewReturnType 1075 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1076 QualType ResQT; 1077 if (OldReturnType != NewReturnType) { 1078 if (NewReturnType->isObjCObjectPointerType() 1079 && OldReturnType->isObjCObjectPointerType()) 1080 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1081 if (ResQT.isNull()) { 1082 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1083 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1084 return true; 1085 } 1086 else 1087 NewQType = ResQT; 1088 } 1089 1090 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1091 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1092 if (OldMethod && NewMethod) { 1093 // Preserve triviality. 1094 NewMethod->setTrivial(OldMethod->isTrivial()); 1095 1096 bool isFriend = NewMethod->getFriendObjectKind(); 1097 1098 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1099 // -- Member function declarations with the same name and the 1100 // same parameter types cannot be overloaded if any of them 1101 // is a static member function declaration. 1102 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1103 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1104 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1105 return true; 1106 } 1107 1108 // C++ [class.mem]p1: 1109 // [...] A member shall not be declared twice in the 1110 // member-specification, except that a nested class or member 1111 // class template can be declared and then later defined. 1112 unsigned NewDiag; 1113 if (isa<CXXConstructorDecl>(OldMethod)) 1114 NewDiag = diag::err_constructor_redeclared; 1115 else if (isa<CXXDestructorDecl>(NewMethod)) 1116 NewDiag = diag::err_destructor_redeclared; 1117 else if (isa<CXXConversionDecl>(NewMethod)) 1118 NewDiag = diag::err_conv_function_redeclared; 1119 else 1120 NewDiag = diag::err_member_redeclared; 1121 1122 Diag(New->getLocation(), NewDiag); 1123 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1124 1125 // Complain if this is an explicit declaration of a special 1126 // member that was initially declared implicitly. 1127 // 1128 // As an exception, it's okay to befriend such methods in order 1129 // to permit the implicit constructor/destructor/operator calls. 1130 } else if (OldMethod->isImplicit()) { 1131 if (isFriend) { 1132 NewMethod->setImplicit(); 1133 } else { 1134 Diag(NewMethod->getLocation(), 1135 diag::err_definition_of_implicitly_declared_member) 1136 << New << getSpecialMember(OldMethod); 1137 return true; 1138 } 1139 } 1140 } 1141 1142 // (C++98 8.3.5p3): 1143 // All declarations for a function shall agree exactly in both the 1144 // return type and the parameter-type-list. 1145 // attributes should be ignored when comparing. 1146 if (Context.getNoReturnType(OldQType, false) == 1147 Context.getNoReturnType(NewQType, false)) 1148 return MergeCompatibleFunctionDecls(New, Old); 1149 1150 // Fall through for conflicting redeclarations and redefinitions. 1151 } 1152 1153 // C: Function types need to be compatible, not identical. This handles 1154 // duplicate function decls like "void f(int); void f(enum X);" properly. 1155 if (!getLangOptions().CPlusPlus && 1156 Context.typesAreCompatible(OldQType, NewQType)) { 1157 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1158 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1159 const FunctionProtoType *OldProto = 0; 1160 if (isa<FunctionNoProtoType>(NewFuncType) && 1161 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1162 // The old declaration provided a function prototype, but the 1163 // new declaration does not. Merge in the prototype. 1164 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1165 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1166 OldProto->arg_type_end()); 1167 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1168 ParamTypes.data(), ParamTypes.size(), 1169 OldProto->isVariadic(), 1170 OldProto->getTypeQuals(), 1171 false, false, 0, 0, 1172 OldProto->getExtInfo()); 1173 New->setType(NewQType); 1174 New->setHasInheritedPrototype(); 1175 1176 // Synthesize a parameter for each argument type. 1177 llvm::SmallVector<ParmVarDecl*, 16> Params; 1178 for (FunctionProtoType::arg_type_iterator 1179 ParamType = OldProto->arg_type_begin(), 1180 ParamEnd = OldProto->arg_type_end(); 1181 ParamType != ParamEnd; ++ParamType) { 1182 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1183 SourceLocation(), 0, 1184 *ParamType, /*TInfo=*/0, 1185 VarDecl::None, VarDecl::None, 1186 0); 1187 Param->setImplicit(); 1188 Params.push_back(Param); 1189 } 1190 1191 New->setParams(Params.data(), Params.size()); 1192 } 1193 1194 return MergeCompatibleFunctionDecls(New, Old); 1195 } 1196 1197 // GNU C permits a K&R definition to follow a prototype declaration 1198 // if the declared types of the parameters in the K&R definition 1199 // match the types in the prototype declaration, even when the 1200 // promoted types of the parameters from the K&R definition differ 1201 // from the types in the prototype. GCC then keeps the types from 1202 // the prototype. 1203 // 1204 // If a variadic prototype is followed by a non-variadic K&R definition, 1205 // the K&R definition becomes variadic. This is sort of an edge case, but 1206 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1207 // C99 6.9.1p8. 1208 if (!getLangOptions().CPlusPlus && 1209 Old->hasPrototype() && !New->hasPrototype() && 1210 New->getType()->getAs<FunctionProtoType>() && 1211 Old->getNumParams() == New->getNumParams()) { 1212 llvm::SmallVector<QualType, 16> ArgTypes; 1213 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1214 const FunctionProtoType *OldProto 1215 = Old->getType()->getAs<FunctionProtoType>(); 1216 const FunctionProtoType *NewProto 1217 = New->getType()->getAs<FunctionProtoType>(); 1218 1219 // Determine whether this is the GNU C extension. 1220 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1221 NewProto->getResultType()); 1222 bool LooseCompatible = !MergedReturn.isNull(); 1223 for (unsigned Idx = 0, End = Old->getNumParams(); 1224 LooseCompatible && Idx != End; ++Idx) { 1225 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1226 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1227 if (Context.typesAreCompatible(OldParm->getType(), 1228 NewProto->getArgType(Idx))) { 1229 ArgTypes.push_back(NewParm->getType()); 1230 } else if (Context.typesAreCompatible(OldParm->getType(), 1231 NewParm->getType())) { 1232 GNUCompatibleParamWarning Warn 1233 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1234 Warnings.push_back(Warn); 1235 ArgTypes.push_back(NewParm->getType()); 1236 } else 1237 LooseCompatible = false; 1238 } 1239 1240 if (LooseCompatible) { 1241 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1242 Diag(Warnings[Warn].NewParm->getLocation(), 1243 diag::ext_param_promoted_not_compatible_with_prototype) 1244 << Warnings[Warn].PromotedType 1245 << Warnings[Warn].OldParm->getType(); 1246 Diag(Warnings[Warn].OldParm->getLocation(), 1247 diag::note_previous_declaration); 1248 } 1249 1250 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1251 ArgTypes.size(), 1252 OldProto->isVariadic(), 0, 1253 false, false, 0, 0, 1254 OldProto->getExtInfo())); 1255 return MergeCompatibleFunctionDecls(New, Old); 1256 } 1257 1258 // Fall through to diagnose conflicting types. 1259 } 1260 1261 // A function that has already been declared has been redeclared or defined 1262 // with a different type- show appropriate diagnostic 1263 if (unsigned BuiltinID = Old->getBuiltinID()) { 1264 // The user has declared a builtin function with an incompatible 1265 // signature. 1266 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1267 // The function the user is redeclaring is a library-defined 1268 // function like 'malloc' or 'printf'. Warn about the 1269 // redeclaration, then pretend that we don't know about this 1270 // library built-in. 1271 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1272 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1273 << Old << Old->getType(); 1274 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1275 Old->setInvalidDecl(); 1276 return false; 1277 } 1278 1279 PrevDiag = diag::note_previous_builtin_declaration; 1280 } 1281 1282 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1283 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1284 return true; 1285} 1286 1287/// \brief Completes the merge of two function declarations that are 1288/// known to be compatible. 1289/// 1290/// This routine handles the merging of attributes and other 1291/// properties of function declarations form the old declaration to 1292/// the new declaration, once we know that New is in fact a 1293/// redeclaration of Old. 1294/// 1295/// \returns false 1296bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1297 // Merge the attributes 1298 MergeAttributes(New, Old, Context); 1299 1300 // Merge the storage class. 1301 if (Old->getStorageClass() != FunctionDecl::Extern && 1302 Old->getStorageClass() != FunctionDecl::None) 1303 New->setStorageClass(Old->getStorageClass()); 1304 1305 // Merge "pure" flag. 1306 if (Old->isPure()) 1307 New->setPure(); 1308 1309 // Merge the "deleted" flag. 1310 if (Old->isDeleted()) 1311 New->setDeleted(); 1312 1313 if (getLangOptions().CPlusPlus) 1314 return MergeCXXFunctionDecl(New, Old); 1315 1316 return false; 1317} 1318 1319/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1320/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1321/// situation, merging decls or emitting diagnostics as appropriate. 1322/// 1323/// Tentative definition rules (C99 6.9.2p2) are checked by 1324/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1325/// definitions here, since the initializer hasn't been attached. 1326/// 1327void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1328 // If the new decl is already invalid, don't do any other checking. 1329 if (New->isInvalidDecl()) 1330 return; 1331 1332 // Verify the old decl was also a variable. 1333 VarDecl *Old = 0; 1334 if (!Previous.isSingleResult() || 1335 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1336 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1337 << New->getDeclName(); 1338 Diag(Previous.getRepresentativeDecl()->getLocation(), 1339 diag::note_previous_definition); 1340 return New->setInvalidDecl(); 1341 } 1342 1343 MergeAttributes(New, Old, Context); 1344 1345 // Merge the types 1346 QualType MergedT; 1347 if (getLangOptions().CPlusPlus) { 1348 if (Context.hasSameType(New->getType(), Old->getType())) 1349 MergedT = New->getType(); 1350 // C++ [basic.link]p10: 1351 // [...] the types specified by all declarations referring to a given 1352 // object or function shall be identical, except that declarations for an 1353 // array object can specify array types that differ by the presence or 1354 // absence of a major array bound (8.3.4). 1355 else if (Old->getType()->isIncompleteArrayType() && 1356 New->getType()->isArrayType()) { 1357 CanQual<ArrayType> OldArray 1358 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1359 CanQual<ArrayType> NewArray 1360 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1361 if (OldArray->getElementType() == NewArray->getElementType()) 1362 MergedT = New->getType(); 1363 } else if (Old->getType()->isArrayType() && 1364 New->getType()->isIncompleteArrayType()) { 1365 CanQual<ArrayType> OldArray 1366 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1367 CanQual<ArrayType> NewArray 1368 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1369 if (OldArray->getElementType() == NewArray->getElementType()) 1370 MergedT = Old->getType(); 1371 } else if (New->getType()->isObjCObjectPointerType() 1372 && Old->getType()->isObjCObjectPointerType()) { 1373 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1374 } 1375 } else { 1376 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1377 } 1378 if (MergedT.isNull()) { 1379 Diag(New->getLocation(), diag::err_redefinition_different_type) 1380 << New->getDeclName(); 1381 Diag(Old->getLocation(), diag::note_previous_definition); 1382 return New->setInvalidDecl(); 1383 } 1384 New->setType(MergedT); 1385 1386 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1387 if (New->getStorageClass() == VarDecl::Static && 1388 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1389 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1390 Diag(Old->getLocation(), diag::note_previous_definition); 1391 return New->setInvalidDecl(); 1392 } 1393 // C99 6.2.2p4: 1394 // For an identifier declared with the storage-class specifier 1395 // extern in a scope in which a prior declaration of that 1396 // identifier is visible,23) if the prior declaration specifies 1397 // internal or external linkage, the linkage of the identifier at 1398 // the later declaration is the same as the linkage specified at 1399 // the prior declaration. If no prior declaration is visible, or 1400 // if the prior declaration specifies no linkage, then the 1401 // identifier has external linkage. 1402 if (New->hasExternalStorage() && Old->hasLinkage()) 1403 /* Okay */; 1404 else if (New->getStorageClass() != VarDecl::Static && 1405 Old->getStorageClass() == VarDecl::Static) { 1406 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1407 Diag(Old->getLocation(), diag::note_previous_definition); 1408 return New->setInvalidDecl(); 1409 } 1410 1411 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1412 1413 // FIXME: The test for external storage here seems wrong? We still 1414 // need to check for mismatches. 1415 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1416 // Don't complain about out-of-line definitions of static members. 1417 !(Old->getLexicalDeclContext()->isRecord() && 1418 !New->getLexicalDeclContext()->isRecord())) { 1419 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1420 Diag(Old->getLocation(), diag::note_previous_definition); 1421 return New->setInvalidDecl(); 1422 } 1423 1424 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1425 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1426 Diag(Old->getLocation(), diag::note_previous_definition); 1427 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1428 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1429 Diag(Old->getLocation(), diag::note_previous_definition); 1430 } 1431 1432 // C++ doesn't have tentative definitions, so go right ahead and check here. 1433 const VarDecl *Def; 1434 if (getLangOptions().CPlusPlus && 1435 New->isThisDeclarationADefinition() == VarDecl::Definition && 1436 (Def = Old->getDefinition())) { 1437 Diag(New->getLocation(), diag::err_redefinition) 1438 << New->getDeclName(); 1439 Diag(Def->getLocation(), diag::note_previous_definition); 1440 New->setInvalidDecl(); 1441 return; 1442 } 1443 1444 // Keep a chain of previous declarations. 1445 New->setPreviousDeclaration(Old); 1446 1447 // Inherit access appropriately. 1448 New->setAccess(Old->getAccess()); 1449} 1450 1451/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1452/// no declarator (e.g. "struct foo;") is parsed. 1453Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1454 DeclSpec &DS) { 1455 // FIXME: Error on auto/register at file scope 1456 // FIXME: Error on inline/virtual/explicit 1457 // FIXME: Warn on useless __thread 1458 // FIXME: Warn on useless const/volatile 1459 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1460 // FIXME: Warn on useless attributes 1461 Decl *TagD = 0; 1462 TagDecl *Tag = 0; 1463 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1464 DS.getTypeSpecType() == DeclSpec::TST_struct || 1465 DS.getTypeSpecType() == DeclSpec::TST_union || 1466 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1467 TagD = static_cast<Decl *>(DS.getTypeRep()); 1468 1469 if (!TagD) // We probably had an error 1470 return DeclPtrTy(); 1471 1472 // Note that the above type specs guarantee that the 1473 // type rep is a Decl, whereas in many of the others 1474 // it's a Type. 1475 Tag = dyn_cast<TagDecl>(TagD); 1476 } 1477 1478 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1479 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1480 // or incomplete types shall not be restrict-qualified." 1481 if (TypeQuals & DeclSpec::TQ_restrict) 1482 Diag(DS.getRestrictSpecLoc(), 1483 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1484 << DS.getSourceRange(); 1485 } 1486 1487 if (DS.isFriendSpecified()) { 1488 // If we're dealing with a class template decl, assume that the 1489 // template routines are handling it. 1490 if (TagD && isa<ClassTemplateDecl>(TagD)) 1491 return DeclPtrTy(); 1492 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1493 } 1494 1495 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1496 // If there are attributes in the DeclSpec, apply them to the record. 1497 if (const AttributeList *AL = DS.getAttributes()) 1498 ProcessDeclAttributeList(S, Record, AL); 1499 1500 if (!Record->getDeclName() && Record->isDefinition() && 1501 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1502 if (getLangOptions().CPlusPlus || 1503 Record->getDeclContext()->isRecord()) 1504 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1505 1506 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1507 << DS.getSourceRange(); 1508 } 1509 1510 // Microsoft allows unnamed struct/union fields. Don't complain 1511 // about them. 1512 // FIXME: Should we support Microsoft's extensions in this area? 1513 if (Record->getDeclName() && getLangOptions().Microsoft) 1514 return DeclPtrTy::make(Tag); 1515 } 1516 1517 if (!DS.isMissingDeclaratorOk() && 1518 DS.getTypeSpecType() != DeclSpec::TST_error) { 1519 // Warn about typedefs of enums without names, since this is an 1520 // extension in both Microsoft an GNU. 1521 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1522 Tag && isa<EnumDecl>(Tag)) { 1523 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1524 << DS.getSourceRange(); 1525 return DeclPtrTy::make(Tag); 1526 } 1527 1528 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1529 << DS.getSourceRange(); 1530 } 1531 1532 return DeclPtrTy::make(Tag); 1533} 1534 1535/// We are trying to inject an anonymous member into the given scope; 1536/// check if there's an existing declaration that can't be overloaded. 1537/// 1538/// \return true if this is a forbidden redeclaration 1539static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1540 Scope *S, 1541 DeclContext *Owner, 1542 DeclarationName Name, 1543 SourceLocation NameLoc, 1544 unsigned diagnostic) { 1545 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1546 Sema::ForRedeclaration); 1547 if (!SemaRef.LookupName(R, S)) return false; 1548 1549 if (R.getAsSingle<TagDecl>()) 1550 return false; 1551 1552 // Pick a representative declaration. 1553 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1554 if (PrevDecl && Owner->isRecord()) { 1555 RecordDecl *Record = cast<RecordDecl>(Owner); 1556 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1557 return false; 1558 } 1559 1560 SemaRef.Diag(NameLoc, diagnostic) << Name; 1561 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1562 1563 return true; 1564} 1565 1566/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1567/// anonymous struct or union AnonRecord into the owning context Owner 1568/// and scope S. This routine will be invoked just after we realize 1569/// that an unnamed union or struct is actually an anonymous union or 1570/// struct, e.g., 1571/// 1572/// @code 1573/// union { 1574/// int i; 1575/// float f; 1576/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1577/// // f into the surrounding scope.x 1578/// @endcode 1579/// 1580/// This routine is recursive, injecting the names of nested anonymous 1581/// structs/unions into the owning context and scope as well. 1582static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1583 DeclContext *Owner, 1584 RecordDecl *AnonRecord, 1585 AccessSpecifier AS) { 1586 unsigned diagKind 1587 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1588 : diag::err_anonymous_struct_member_redecl; 1589 1590 bool Invalid = false; 1591 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1592 FEnd = AnonRecord->field_end(); 1593 F != FEnd; ++F) { 1594 if ((*F)->getDeclName()) { 1595 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1596 (*F)->getLocation(), diagKind)) { 1597 // C++ [class.union]p2: 1598 // The names of the members of an anonymous union shall be 1599 // distinct from the names of any other entity in the 1600 // scope in which the anonymous union is declared. 1601 Invalid = true; 1602 } else { 1603 // C++ [class.union]p2: 1604 // For the purpose of name lookup, after the anonymous union 1605 // definition, the members of the anonymous union are 1606 // considered to have been defined in the scope in which the 1607 // anonymous union is declared. 1608 Owner->makeDeclVisibleInContext(*F); 1609 S->AddDecl(Sema::DeclPtrTy::make(*F)); 1610 SemaRef.IdResolver.AddDecl(*F); 1611 1612 // That includes picking up the appropriate access specifier. 1613 if (AS != AS_none) (*F)->setAccess(AS); 1614 } 1615 } else if (const RecordType *InnerRecordType 1616 = (*F)->getType()->getAs<RecordType>()) { 1617 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1618 if (InnerRecord->isAnonymousStructOrUnion()) 1619 Invalid = Invalid || 1620 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1621 InnerRecord, AS); 1622 } 1623 } 1624 1625 return Invalid; 1626} 1627 1628/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1629/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1630/// illegal input values are mapped to VarDecl::None. 1631/// If the input declaration context is a linkage specification 1632/// with no braces, then Extern is mapped to None. 1633static VarDecl::StorageClass 1634StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1635 DeclContext *DC) { 1636 switch (StorageClassSpec) { 1637 case DeclSpec::SCS_unspecified: return VarDecl::None; 1638 case DeclSpec::SCS_extern: 1639 // If the current context is a C++ linkage specification 1640 // having no braces, then the keyword "extern" is properly part 1641 // of the linkage specification itself, rather than being 1642 // the written storage class specifier. 1643 return (DC && isa<LinkageSpecDecl>(DC) && 1644 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1645 ? VarDecl::None : VarDecl::Extern; 1646 case DeclSpec::SCS_static: return VarDecl::Static; 1647 case DeclSpec::SCS_auto: return VarDecl::Auto; 1648 case DeclSpec::SCS_register: return VarDecl::Register; 1649 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1650 // Illegal SCSs map to None: error reporting is up to the caller. 1651 case DeclSpec::SCS_mutable: // Fall through. 1652 case DeclSpec::SCS_typedef: return VarDecl::None; 1653 } 1654 llvm_unreachable("unknown storage class specifier"); 1655} 1656 1657/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1658/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1659/// illegal input values are mapped to FunctionDecl::None. 1660/// If the input declaration context is a linkage specification 1661/// with no braces, then Extern is mapped to None. 1662static FunctionDecl::StorageClass 1663StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1664 DeclContext *DC) { 1665 switch (StorageClassSpec) { 1666 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1667 case DeclSpec::SCS_extern: 1668 // If the current context is a C++ linkage specification 1669 // having no braces, then the keyword "extern" is properly part 1670 // of the linkage specification itself, rather than being 1671 // the written storage class specifier. 1672 return (DC && isa<LinkageSpecDecl>(DC) && 1673 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1674 ? FunctionDecl::None : FunctionDecl::Extern; 1675 case DeclSpec::SCS_static: return FunctionDecl::Static; 1676 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1677 // Illegal SCSs map to None: error reporting is up to the caller. 1678 case DeclSpec::SCS_auto: // Fall through. 1679 case DeclSpec::SCS_mutable: // Fall through. 1680 case DeclSpec::SCS_register: // Fall through. 1681 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1682 } 1683 llvm_unreachable("unknown storage class specifier"); 1684} 1685 1686/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1687/// anonymous structure or union. Anonymous unions are a C++ feature 1688/// (C++ [class.union]) and a GNU C extension; anonymous structures 1689/// are a GNU C and GNU C++ extension. 1690Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1691 AccessSpecifier AS, 1692 RecordDecl *Record) { 1693 DeclContext *Owner = Record->getDeclContext(); 1694 1695 // Diagnose whether this anonymous struct/union is an extension. 1696 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1697 Diag(Record->getLocation(), diag::ext_anonymous_union); 1698 else if (!Record->isUnion()) 1699 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1700 1701 // C and C++ require different kinds of checks for anonymous 1702 // structs/unions. 1703 bool Invalid = false; 1704 if (getLangOptions().CPlusPlus) { 1705 const char* PrevSpec = 0; 1706 unsigned DiagID; 1707 // C++ [class.union]p3: 1708 // Anonymous unions declared in a named namespace or in the 1709 // global namespace shall be declared static. 1710 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1711 (isa<TranslationUnitDecl>(Owner) || 1712 (isa<NamespaceDecl>(Owner) && 1713 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1714 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1715 Invalid = true; 1716 1717 // Recover by adding 'static'. 1718 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1719 PrevSpec, DiagID); 1720 } 1721 // C++ [class.union]p3: 1722 // A storage class is not allowed in a declaration of an 1723 // anonymous union in a class scope. 1724 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1725 isa<RecordDecl>(Owner)) { 1726 Diag(DS.getStorageClassSpecLoc(), 1727 diag::err_anonymous_union_with_storage_spec); 1728 Invalid = true; 1729 1730 // Recover by removing the storage specifier. 1731 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1732 PrevSpec, DiagID); 1733 } 1734 1735 // C++ [class.union]p2: 1736 // The member-specification of an anonymous union shall only 1737 // define non-static data members. [Note: nested types and 1738 // functions cannot be declared within an anonymous union. ] 1739 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1740 MemEnd = Record->decls_end(); 1741 Mem != MemEnd; ++Mem) { 1742 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1743 // C++ [class.union]p3: 1744 // An anonymous union shall not have private or protected 1745 // members (clause 11). 1746 assert(FD->getAccess() != AS_none); 1747 if (FD->getAccess() != AS_public) { 1748 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1749 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1750 Invalid = true; 1751 } 1752 } else if ((*Mem)->isImplicit()) { 1753 // Any implicit members are fine. 1754 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1755 // This is a type that showed up in an 1756 // elaborated-type-specifier inside the anonymous struct or 1757 // union, but which actually declares a type outside of the 1758 // anonymous struct or union. It's okay. 1759 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1760 if (!MemRecord->isAnonymousStructOrUnion() && 1761 MemRecord->getDeclName()) { 1762 // This is a nested type declaration. 1763 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1764 << (int)Record->isUnion(); 1765 Invalid = true; 1766 } 1767 } else if (isa<AccessSpecDecl>(*Mem)) { 1768 // Any access specifier is fine. 1769 } else { 1770 // We have something that isn't a non-static data 1771 // member. Complain about it. 1772 unsigned DK = diag::err_anonymous_record_bad_member; 1773 if (isa<TypeDecl>(*Mem)) 1774 DK = diag::err_anonymous_record_with_type; 1775 else if (isa<FunctionDecl>(*Mem)) 1776 DK = diag::err_anonymous_record_with_function; 1777 else if (isa<VarDecl>(*Mem)) 1778 DK = diag::err_anonymous_record_with_static; 1779 Diag((*Mem)->getLocation(), DK) 1780 << (int)Record->isUnion(); 1781 Invalid = true; 1782 } 1783 } 1784 } 1785 1786 if (!Record->isUnion() && !Owner->isRecord()) { 1787 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1788 << (int)getLangOptions().CPlusPlus; 1789 Invalid = true; 1790 } 1791 1792 // Mock up a declarator. 1793 Declarator Dc(DS, Declarator::TypeNameContext); 1794 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1795 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1796 1797 // Create a declaration for this anonymous struct/union. 1798 NamedDecl *Anon = 0; 1799 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1800 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1801 /*IdentifierInfo=*/0, 1802 Context.getTypeDeclType(Record), 1803 TInfo, 1804 /*BitWidth=*/0, /*Mutable=*/false); 1805 Anon->setAccess(AS); 1806 if (getLangOptions().CPlusPlus) { 1807 FieldCollector->Add(cast<FieldDecl>(Anon)); 1808 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1809 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1810 } 1811 } else { 1812 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1813 assert(SCSpec != DeclSpec::SCS_typedef && 1814 "Parser allowed 'typedef' as storage class VarDecl."); 1815 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1816 if (SCSpec == DeclSpec::SCS_mutable) { 1817 // mutable can only appear on non-static class members, so it's always 1818 // an error here 1819 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1820 Invalid = true; 1821 SC = VarDecl::None; 1822 } 1823 SCSpec = DS.getStorageClassSpecAsWritten(); 1824 VarDecl::StorageClass SCAsWritten 1825 = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1826 1827 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1828 /*IdentifierInfo=*/0, 1829 Context.getTypeDeclType(Record), 1830 TInfo, SC, SCAsWritten); 1831 } 1832 Anon->setImplicit(); 1833 1834 // Add the anonymous struct/union object to the current 1835 // context. We'll be referencing this object when we refer to one of 1836 // its members. 1837 Owner->addDecl(Anon); 1838 1839 // Inject the members of the anonymous struct/union into the owning 1840 // context and into the identifier resolver chain for name lookup 1841 // purposes. 1842 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1843 Invalid = true; 1844 1845 // Mark this as an anonymous struct/union type. Note that we do not 1846 // do this until after we have already checked and injected the 1847 // members of this anonymous struct/union type, because otherwise 1848 // the members could be injected twice: once by DeclContext when it 1849 // builds its lookup table, and once by 1850 // InjectAnonymousStructOrUnionMembers. 1851 Record->setAnonymousStructOrUnion(true); 1852 1853 if (Invalid) 1854 Anon->setInvalidDecl(); 1855 1856 return DeclPtrTy::make(Anon); 1857} 1858 1859 1860/// GetNameForDeclarator - Determine the full declaration name for the 1861/// given Declarator. 1862DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1863 return GetNameFromUnqualifiedId(D.getName()); 1864} 1865 1866/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1867DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1868 switch (Name.getKind()) { 1869 case UnqualifiedId::IK_Identifier: 1870 return DeclarationName(Name.Identifier); 1871 1872 case UnqualifiedId::IK_OperatorFunctionId: 1873 return Context.DeclarationNames.getCXXOperatorName( 1874 Name.OperatorFunctionId.Operator); 1875 1876 case UnqualifiedId::IK_LiteralOperatorId: 1877 return Context.DeclarationNames.getCXXLiteralOperatorName( 1878 Name.Identifier); 1879 1880 case UnqualifiedId::IK_ConversionFunctionId: { 1881 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1882 if (Ty.isNull()) 1883 return DeclarationName(); 1884 1885 return Context.DeclarationNames.getCXXConversionFunctionName( 1886 Context.getCanonicalType(Ty)); 1887 } 1888 1889 case UnqualifiedId::IK_ConstructorName: { 1890 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1891 if (Ty.isNull()) 1892 return DeclarationName(); 1893 1894 return Context.DeclarationNames.getCXXConstructorName( 1895 Context.getCanonicalType(Ty)); 1896 } 1897 1898 case UnqualifiedId::IK_ConstructorTemplateId: { 1899 // In well-formed code, we can only have a constructor 1900 // template-id that refers to the current context, so go there 1901 // to find the actual type being constructed. 1902 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1903 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1904 return DeclarationName(); 1905 1906 // Determine the type of the class being constructed. 1907 QualType CurClassType = Context.getTypeDeclType(CurClass); 1908 1909 // FIXME: Check two things: that the template-id names the same type as 1910 // CurClassType, and that the template-id does not occur when the name 1911 // was qualified. 1912 1913 return Context.DeclarationNames.getCXXConstructorName( 1914 Context.getCanonicalType(CurClassType)); 1915 } 1916 1917 case UnqualifiedId::IK_DestructorName: { 1918 QualType Ty = GetTypeFromParser(Name.DestructorName); 1919 if (Ty.isNull()) 1920 return DeclarationName(); 1921 1922 return Context.DeclarationNames.getCXXDestructorName( 1923 Context.getCanonicalType(Ty)); 1924 } 1925 1926 case UnqualifiedId::IK_TemplateId: { 1927 TemplateName TName 1928 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1929 return Context.getNameForTemplate(TName); 1930 } 1931 } 1932 1933 assert(false && "Unknown name kind"); 1934 return DeclarationName(); 1935} 1936 1937/// isNearlyMatchingFunction - Determine whether the C++ functions 1938/// Declaration and Definition are "nearly" matching. This heuristic 1939/// is used to improve diagnostics in the case where an out-of-line 1940/// function definition doesn't match any declaration within 1941/// the class or namespace. 1942static bool isNearlyMatchingFunction(ASTContext &Context, 1943 FunctionDecl *Declaration, 1944 FunctionDecl *Definition) { 1945 if (Declaration->param_size() != Definition->param_size()) 1946 return false; 1947 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1948 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1949 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1950 1951 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1952 DefParamTy.getNonReferenceType())) 1953 return false; 1954 } 1955 1956 return true; 1957} 1958 1959/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 1960/// declarator needs to be rebuilt in the current instantiation. 1961/// Any bits of declarator which appear before the name are valid for 1962/// consideration here. That's specifically the type in the decl spec 1963/// and the base type in any member-pointer chunks. 1964static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 1965 DeclarationName Name) { 1966 // The types we specifically need to rebuild are: 1967 // - typenames, typeofs, and decltypes 1968 // - types which will become injected class names 1969 // Of course, we also need to rebuild any type referencing such a 1970 // type. It's safest to just say "dependent", but we call out a 1971 // few cases here. 1972 1973 DeclSpec &DS = D.getMutableDeclSpec(); 1974 switch (DS.getTypeSpecType()) { 1975 case DeclSpec::TST_typename: 1976 case DeclSpec::TST_typeofType: 1977 case DeclSpec::TST_typeofExpr: 1978 case DeclSpec::TST_decltype: { 1979 // Grab the type from the parser. 1980 TypeSourceInfo *TSI = 0; 1981 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 1982 if (T.isNull() || !T->isDependentType()) break; 1983 1984 // Make sure there's a type source info. This isn't really much 1985 // of a waste; most dependent types should have type source info 1986 // attached already. 1987 if (!TSI) 1988 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 1989 1990 // Rebuild the type in the current instantiation. 1991 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 1992 if (!TSI) return true; 1993 1994 // Store the new type back in the decl spec. 1995 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 1996 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 1997 break; 1998 } 1999 2000 default: 2001 // Nothing to do for these decl specs. 2002 break; 2003 } 2004 2005 // It doesn't matter what order we do this in. 2006 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2007 DeclaratorChunk &Chunk = D.getTypeObject(I); 2008 2009 // The only type information in the declarator which can come 2010 // before the declaration name is the base type of a member 2011 // pointer. 2012 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2013 continue; 2014 2015 // Rebuild the scope specifier in-place. 2016 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2017 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2018 return true; 2019 } 2020 2021 return false; 2022} 2023 2024Sema::DeclPtrTy 2025Sema::HandleDeclarator(Scope *S, Declarator &D, 2026 MultiTemplateParamsArg TemplateParamLists, 2027 bool IsFunctionDefinition) { 2028 DeclarationName Name = GetNameForDeclarator(D); 2029 2030 // All of these full declarators require an identifier. If it doesn't have 2031 // one, the ParsedFreeStandingDeclSpec action should be used. 2032 if (!Name) { 2033 if (!D.isInvalidType()) // Reject this if we think it is valid. 2034 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2035 diag::err_declarator_need_ident) 2036 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2037 return DeclPtrTy(); 2038 } 2039 2040 // The scope passed in may not be a decl scope. Zip up the scope tree until 2041 // we find one that is. 2042 while ((S->getFlags() & Scope::DeclScope) == 0 || 2043 (S->getFlags() & Scope::TemplateParamScope) != 0) 2044 S = S->getParent(); 2045 2046 DeclContext *DC = CurContext; 2047 if (D.getCXXScopeSpec().isInvalid()) 2048 D.setInvalidType(); 2049 else if (D.getCXXScopeSpec().isSet()) { 2050 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2051 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2052 if (!DC) { 2053 // If we could not compute the declaration context, it's because the 2054 // declaration context is dependent but does not refer to a class, 2055 // class template, or class template partial specialization. Complain 2056 // and return early, to avoid the coming semantic disaster. 2057 Diag(D.getIdentifierLoc(), 2058 diag::err_template_qualified_declarator_no_match) 2059 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2060 << D.getCXXScopeSpec().getRange(); 2061 return DeclPtrTy(); 2062 } 2063 2064 bool IsDependentContext = DC->isDependentContext(); 2065 2066 if (!IsDependentContext && 2067 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2068 return DeclPtrTy(); 2069 2070 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2071 Diag(D.getIdentifierLoc(), 2072 diag::err_member_def_undefined_record) 2073 << Name << DC << D.getCXXScopeSpec().getRange(); 2074 D.setInvalidType(); 2075 } 2076 2077 // Check whether we need to rebuild the type of the given 2078 // declaration in the current instantiation. 2079 if (EnteringContext && IsDependentContext && 2080 TemplateParamLists.size() != 0) { 2081 ContextRAII SavedContext(*this, DC); 2082 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2083 D.setInvalidType(); 2084 } 2085 } 2086 2087 NamedDecl *New; 2088 2089 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2090 QualType R = TInfo->getType(); 2091 2092 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2093 ForRedeclaration); 2094 2095 // See if this is a redefinition of a variable in the same scope. 2096 if (!D.getCXXScopeSpec().isSet()) { 2097 bool IsLinkageLookup = false; 2098 2099 // If the declaration we're planning to build will be a function 2100 // or object with linkage, then look for another declaration with 2101 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2102 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2103 /* Do nothing*/; 2104 else if (R->isFunctionType()) { 2105 if (CurContext->isFunctionOrMethod() || 2106 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2107 IsLinkageLookup = true; 2108 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2109 IsLinkageLookup = true; 2110 else if (CurContext->getLookupContext()->isTranslationUnit() && 2111 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2112 IsLinkageLookup = true; 2113 2114 if (IsLinkageLookup) 2115 Previous.clear(LookupRedeclarationWithLinkage); 2116 2117 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2118 } else { // Something like "int foo::x;" 2119 LookupQualifiedName(Previous, DC); 2120 2121 // Don't consider using declarations as previous declarations for 2122 // out-of-line members. 2123 RemoveUsingDecls(Previous); 2124 2125 // C++ 7.3.1.2p2: 2126 // Members (including explicit specializations of templates) of a named 2127 // namespace can also be defined outside that namespace by explicit 2128 // qualification of the name being defined, provided that the entity being 2129 // defined was already declared in the namespace and the definition appears 2130 // after the point of declaration in a namespace that encloses the 2131 // declarations namespace. 2132 // 2133 // Note that we only check the context at this point. We don't yet 2134 // have enough information to make sure that PrevDecl is actually 2135 // the declaration we want to match. For example, given: 2136 // 2137 // class X { 2138 // void f(); 2139 // void f(float); 2140 // }; 2141 // 2142 // void X::f(int) { } // ill-formed 2143 // 2144 // In this case, PrevDecl will point to the overload set 2145 // containing the two f's declared in X, but neither of them 2146 // matches. 2147 2148 // First check whether we named the global scope. 2149 if (isa<TranslationUnitDecl>(DC)) { 2150 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2151 << Name << D.getCXXScopeSpec().getRange(); 2152 } else { 2153 DeclContext *Cur = CurContext; 2154 while (isa<LinkageSpecDecl>(Cur)) 2155 Cur = Cur->getParent(); 2156 if (!Cur->Encloses(DC)) { 2157 // The qualifying scope doesn't enclose the original declaration. 2158 // Emit diagnostic based on current scope. 2159 SourceLocation L = D.getIdentifierLoc(); 2160 SourceRange R = D.getCXXScopeSpec().getRange(); 2161 if (isa<FunctionDecl>(Cur)) 2162 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2163 else 2164 Diag(L, diag::err_invalid_declarator_scope) 2165 << Name << cast<NamedDecl>(DC) << R; 2166 D.setInvalidType(); 2167 } 2168 } 2169 } 2170 2171 if (Previous.isSingleResult() && 2172 Previous.getFoundDecl()->isTemplateParameter()) { 2173 // Maybe we will complain about the shadowed template parameter. 2174 if (!D.isInvalidType()) 2175 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2176 Previous.getFoundDecl())) 2177 D.setInvalidType(); 2178 2179 // Just pretend that we didn't see the previous declaration. 2180 Previous.clear(); 2181 } 2182 2183 // In C++, the previous declaration we find might be a tag type 2184 // (class or enum). In this case, the new declaration will hide the 2185 // tag type. Note that this does does not apply if we're declaring a 2186 // typedef (C++ [dcl.typedef]p4). 2187 if (Previous.isSingleTagDecl() && 2188 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2189 Previous.clear(); 2190 2191 bool Redeclaration = false; 2192 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2193 if (TemplateParamLists.size()) { 2194 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2195 return DeclPtrTy(); 2196 } 2197 2198 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2199 } else if (R->isFunctionType()) { 2200 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2201 move(TemplateParamLists), 2202 IsFunctionDefinition, Redeclaration); 2203 } else { 2204 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2205 move(TemplateParamLists), 2206 Redeclaration); 2207 } 2208 2209 if (New == 0) 2210 return DeclPtrTy(); 2211 2212 // If this has an identifier and is not an invalid redeclaration or 2213 // function template specialization, add it to the scope stack. 2214 if (Name && !(Redeclaration && New->isInvalidDecl())) 2215 PushOnScopeChains(New, S); 2216 2217 return DeclPtrTy::make(New); 2218} 2219 2220/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2221/// types into constant array types in certain situations which would otherwise 2222/// be errors (for GCC compatibility). 2223static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2224 ASTContext &Context, 2225 bool &SizeIsNegative) { 2226 // This method tries to turn a variable array into a constant 2227 // array even when the size isn't an ICE. This is necessary 2228 // for compatibility with code that depends on gcc's buggy 2229 // constant expression folding, like struct {char x[(int)(char*)2];} 2230 SizeIsNegative = false; 2231 2232 QualifierCollector Qs; 2233 const Type *Ty = Qs.strip(T); 2234 2235 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2236 QualType Pointee = PTy->getPointeeType(); 2237 QualType FixedType = 2238 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2239 if (FixedType.isNull()) return FixedType; 2240 FixedType = Context.getPointerType(FixedType); 2241 return Qs.apply(FixedType); 2242 } 2243 2244 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2245 if (!VLATy) 2246 return QualType(); 2247 // FIXME: We should probably handle this case 2248 if (VLATy->getElementType()->isVariablyModifiedType()) 2249 return QualType(); 2250 2251 Expr::EvalResult EvalResult; 2252 if (!VLATy->getSizeExpr() || 2253 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2254 !EvalResult.Val.isInt()) 2255 return QualType(); 2256 2257 llvm::APSInt &Res = EvalResult.Val.getInt(); 2258 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2259 // TODO: preserve the size expression in declarator info 2260 return Context.getConstantArrayType(VLATy->getElementType(), 2261 Res, ArrayType::Normal, 0); 2262 } 2263 2264 SizeIsNegative = true; 2265 return QualType(); 2266} 2267 2268/// \brief Register the given locally-scoped external C declaration so 2269/// that it can be found later for redeclarations 2270void 2271Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2272 const LookupResult &Previous, 2273 Scope *S) { 2274 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2275 "Decl is not a locally-scoped decl!"); 2276 // Note that we have a locally-scoped external with this name. 2277 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2278 2279 if (!Previous.isSingleResult()) 2280 return; 2281 2282 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2283 2284 // If there was a previous declaration of this variable, it may be 2285 // in our identifier chain. Update the identifier chain with the new 2286 // declaration. 2287 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2288 // The previous declaration was found on the identifer resolver 2289 // chain, so remove it from its scope. 2290 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2291 S = S->getParent(); 2292 2293 if (S) 2294 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2295 } 2296} 2297 2298/// \brief Diagnose function specifiers on a declaration of an identifier that 2299/// does not identify a function. 2300void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2301 // FIXME: We should probably indicate the identifier in question to avoid 2302 // confusion for constructs like "inline int a(), b;" 2303 if (D.getDeclSpec().isInlineSpecified()) 2304 Diag(D.getDeclSpec().getInlineSpecLoc(), 2305 diag::err_inline_non_function); 2306 2307 if (D.getDeclSpec().isVirtualSpecified()) 2308 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2309 diag::err_virtual_non_function); 2310 2311 if (D.getDeclSpec().isExplicitSpecified()) 2312 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2313 diag::err_explicit_non_function); 2314} 2315 2316NamedDecl* 2317Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2318 QualType R, TypeSourceInfo *TInfo, 2319 LookupResult &Previous, bool &Redeclaration) { 2320 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2321 if (D.getCXXScopeSpec().isSet()) { 2322 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2323 << D.getCXXScopeSpec().getRange(); 2324 D.setInvalidType(); 2325 // Pretend we didn't see the scope specifier. 2326 DC = CurContext; 2327 Previous.clear(); 2328 } 2329 2330 if (getLangOptions().CPlusPlus) { 2331 // Check that there are no default arguments (C++ only). 2332 CheckExtraCXXDefaultArguments(D); 2333 } 2334 2335 DiagnoseFunctionSpecifiers(D); 2336 2337 if (D.getDeclSpec().isThreadSpecified()) 2338 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2339 2340 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2341 if (!NewTD) return 0; 2342 2343 // Handle attributes prior to checking for duplicates in MergeVarDecl 2344 ProcessDeclAttributes(S, NewTD, D); 2345 2346 // Merge the decl with the existing one if appropriate. If the decl is 2347 // in an outer scope, it isn't the same thing. 2348 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2349 if (!Previous.empty()) { 2350 Redeclaration = true; 2351 MergeTypeDefDecl(NewTD, Previous); 2352 } 2353 2354 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2355 // then it shall have block scope. 2356 QualType T = NewTD->getUnderlyingType(); 2357 if (T->isVariablyModifiedType()) { 2358 FunctionNeedsScopeChecking() = true; 2359 2360 if (S->getFnParent() == 0) { 2361 bool SizeIsNegative; 2362 QualType FixedTy = 2363 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2364 if (!FixedTy.isNull()) { 2365 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2366 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2367 } else { 2368 if (SizeIsNegative) 2369 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2370 else if (T->isVariableArrayType()) 2371 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2372 else 2373 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2374 NewTD->setInvalidDecl(); 2375 } 2376 } 2377 } 2378 2379 // If this is the C FILE type, notify the AST context. 2380 if (IdentifierInfo *II = NewTD->getIdentifier()) 2381 if (!NewTD->isInvalidDecl() && 2382 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2383 if (II->isStr("FILE")) 2384 Context.setFILEDecl(NewTD); 2385 else if (II->isStr("jmp_buf")) 2386 Context.setjmp_bufDecl(NewTD); 2387 else if (II->isStr("sigjmp_buf")) 2388 Context.setsigjmp_bufDecl(NewTD); 2389 } 2390 2391 return NewTD; 2392} 2393 2394/// \brief Determines whether the given declaration is an out-of-scope 2395/// previous declaration. 2396/// 2397/// This routine should be invoked when name lookup has found a 2398/// previous declaration (PrevDecl) that is not in the scope where a 2399/// new declaration by the same name is being introduced. If the new 2400/// declaration occurs in a local scope, previous declarations with 2401/// linkage may still be considered previous declarations (C99 2402/// 6.2.2p4-5, C++ [basic.link]p6). 2403/// 2404/// \param PrevDecl the previous declaration found by name 2405/// lookup 2406/// 2407/// \param DC the context in which the new declaration is being 2408/// declared. 2409/// 2410/// \returns true if PrevDecl is an out-of-scope previous declaration 2411/// for a new delcaration with the same name. 2412static bool 2413isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2414 ASTContext &Context) { 2415 if (!PrevDecl) 2416 return 0; 2417 2418 if (!PrevDecl->hasLinkage()) 2419 return false; 2420 2421 if (Context.getLangOptions().CPlusPlus) { 2422 // C++ [basic.link]p6: 2423 // If there is a visible declaration of an entity with linkage 2424 // having the same name and type, ignoring entities declared 2425 // outside the innermost enclosing namespace scope, the block 2426 // scope declaration declares that same entity and receives the 2427 // linkage of the previous declaration. 2428 DeclContext *OuterContext = DC->getLookupContext(); 2429 if (!OuterContext->isFunctionOrMethod()) 2430 // This rule only applies to block-scope declarations. 2431 return false; 2432 else { 2433 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2434 if (PrevOuterContext->isRecord()) 2435 // We found a member function: ignore it. 2436 return false; 2437 else { 2438 // Find the innermost enclosing namespace for the new and 2439 // previous declarations. 2440 while (!OuterContext->isFileContext()) 2441 OuterContext = OuterContext->getParent(); 2442 while (!PrevOuterContext->isFileContext()) 2443 PrevOuterContext = PrevOuterContext->getParent(); 2444 2445 // The previous declaration is in a different namespace, so it 2446 // isn't the same function. 2447 if (OuterContext->getPrimaryContext() != 2448 PrevOuterContext->getPrimaryContext()) 2449 return false; 2450 } 2451 } 2452 } 2453 2454 return true; 2455} 2456 2457static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2458 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2459 if (!SS.isSet()) return; 2460 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2461 SS.getRange()); 2462} 2463 2464NamedDecl* 2465Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2466 QualType R, TypeSourceInfo *TInfo, 2467 LookupResult &Previous, 2468 MultiTemplateParamsArg TemplateParamLists, 2469 bool &Redeclaration) { 2470 DeclarationName Name = GetNameForDeclarator(D); 2471 2472 // Check that there are no default arguments (C++ only). 2473 if (getLangOptions().CPlusPlus) 2474 CheckExtraCXXDefaultArguments(D); 2475 2476 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2477 assert(SCSpec != DeclSpec::SCS_typedef && 2478 "Parser allowed 'typedef' as storage class VarDecl."); 2479 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 2480 if (SCSpec == DeclSpec::SCS_mutable) { 2481 // mutable can only appear on non-static class members, so it's always 2482 // an error here 2483 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2484 D.setInvalidType(); 2485 SC = VarDecl::None; 2486 } 2487 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2488 VarDecl::StorageClass SCAsWritten 2489 = StorageClassSpecToVarDeclStorageClass(SCSpec, DC); 2490 2491 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2492 if (!II) { 2493 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2494 << Name.getAsString(); 2495 return 0; 2496 } 2497 2498 DiagnoseFunctionSpecifiers(D); 2499 2500 if (!DC->isRecord() && S->getFnParent() == 0) { 2501 // C99 6.9p2: The storage-class specifiers auto and register shall not 2502 // appear in the declaration specifiers in an external declaration. 2503 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2504 2505 // If this is a register variable with an asm label specified, then this 2506 // is a GNU extension. 2507 if (SC == VarDecl::Register && D.getAsmLabel()) 2508 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2509 else 2510 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2511 D.setInvalidType(); 2512 } 2513 } 2514 if (DC->isRecord() && !CurContext->isRecord()) { 2515 // This is an out-of-line definition of a static data member. 2516 if (SC == VarDecl::Static) { 2517 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2518 diag::err_static_out_of_line) 2519 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2520 } else if (SC == VarDecl::None) 2521 SC = VarDecl::Static; 2522 } 2523 if (SC == VarDecl::Static) { 2524 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2525 if (RD->isLocalClass()) 2526 Diag(D.getIdentifierLoc(), 2527 diag::err_static_data_member_not_allowed_in_local_class) 2528 << Name << RD->getDeclName(); 2529 } 2530 } 2531 2532 // Match up the template parameter lists with the scope specifier, then 2533 // determine whether we have a template or a template specialization. 2534 bool isExplicitSpecialization = false; 2535 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2536 if (TemplateParameterList *TemplateParams 2537 = MatchTemplateParametersToScopeSpecifier( 2538 D.getDeclSpec().getSourceRange().getBegin(), 2539 D.getCXXScopeSpec(), 2540 (TemplateParameterList**)TemplateParamLists.get(), 2541 TemplateParamLists.size(), 2542 /*never a friend*/ false, 2543 isExplicitSpecialization)) { 2544 // All but one template parameter lists have been matching. 2545 --NumMatchedTemplateParamLists; 2546 2547 if (TemplateParams->size() > 0) { 2548 // There is no such thing as a variable template. 2549 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2550 << II 2551 << SourceRange(TemplateParams->getTemplateLoc(), 2552 TemplateParams->getRAngleLoc()); 2553 return 0; 2554 } else { 2555 // There is an extraneous 'template<>' for this variable. Complain 2556 // about it, but allow the declaration of the variable. 2557 Diag(TemplateParams->getTemplateLoc(), 2558 diag::err_template_variable_noparams) 2559 << II 2560 << SourceRange(TemplateParams->getTemplateLoc(), 2561 TemplateParams->getRAngleLoc()); 2562 2563 isExplicitSpecialization = true; 2564 } 2565 } 2566 2567 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2568 II, R, TInfo, SC, SCAsWritten); 2569 2570 if (D.isInvalidType()) 2571 NewVD->setInvalidDecl(); 2572 2573 SetNestedNameSpecifier(NewVD, D); 2574 2575 if (NumMatchedTemplateParamLists > 0) { 2576 NewVD->setTemplateParameterListsInfo(NumMatchedTemplateParamLists, 2577 (TemplateParameterList**)TemplateParamLists.release()); 2578 } 2579 2580 if (D.getDeclSpec().isThreadSpecified()) { 2581 if (NewVD->hasLocalStorage()) 2582 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2583 else if (!Context.Target.isTLSSupported()) 2584 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2585 else 2586 NewVD->setThreadSpecified(true); 2587 } 2588 2589 // Set the lexical context. If the declarator has a C++ scope specifier, the 2590 // lexical context will be different from the semantic context. 2591 NewVD->setLexicalDeclContext(CurContext); 2592 2593 // Handle attributes prior to checking for duplicates in MergeVarDecl 2594 ProcessDeclAttributes(S, NewVD, D); 2595 2596 // Handle GNU asm-label extension (encoded as an attribute). 2597 if (Expr *E = (Expr*) D.getAsmLabel()) { 2598 // The parser guarantees this is a string. 2599 StringLiteral *SE = cast<StringLiteral>(E); 2600 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2601 } 2602 2603 // Diagnose shadowed variables before filtering for scope. 2604 if (!D.getCXXScopeSpec().isSet()) 2605 CheckShadow(S, NewVD, Previous); 2606 2607 // Don't consider existing declarations that are in a different 2608 // scope and are out-of-semantic-context declarations (if the new 2609 // declaration has linkage). 2610 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2611 2612 // Merge the decl with the existing one if appropriate. 2613 if (!Previous.empty()) { 2614 if (Previous.isSingleResult() && 2615 isa<FieldDecl>(Previous.getFoundDecl()) && 2616 D.getCXXScopeSpec().isSet()) { 2617 // The user tried to define a non-static data member 2618 // out-of-line (C++ [dcl.meaning]p1). 2619 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2620 << D.getCXXScopeSpec().getRange(); 2621 Previous.clear(); 2622 NewVD->setInvalidDecl(); 2623 } 2624 } else if (D.getCXXScopeSpec().isSet()) { 2625 // No previous declaration in the qualifying scope. 2626 Diag(D.getIdentifierLoc(), diag::err_no_member) 2627 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2628 << D.getCXXScopeSpec().getRange(); 2629 NewVD->setInvalidDecl(); 2630 } 2631 2632 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2633 2634 // This is an explicit specialization of a static data member. Check it. 2635 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2636 CheckMemberSpecialization(NewVD, Previous)) 2637 NewVD->setInvalidDecl(); 2638 2639 // attributes declared post-definition are currently ignored 2640 if (Previous.isSingleResult()) { 2641 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2642 if (Def && (Def = Def->getDefinition()) && 2643 Def != NewVD && D.hasAttributes()) { 2644 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2645 Diag(Def->getLocation(), diag::note_previous_definition); 2646 } 2647 } 2648 2649 // If this is a locally-scoped extern C variable, update the map of 2650 // such variables. 2651 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2652 !NewVD->isInvalidDecl()) 2653 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2654 2655 return NewVD; 2656} 2657 2658/// \brief Diagnose variable or built-in function shadowing. Implements 2659/// -Wshadow. 2660/// 2661/// This method is called whenever a VarDecl is added to a "useful" 2662/// scope. 2663/// 2664/// \param S the scope in which the shadowing name is being declared 2665/// \param R the lookup of the name 2666/// 2667void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2668 // Return if warning is ignored. 2669 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2670 return; 2671 2672 // Don't diagnose declarations at file scope. The scope might not 2673 // have a DeclContext if (e.g.) we're parsing a function prototype. 2674 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2675 if (NewDC && NewDC->isFileContext()) 2676 return; 2677 2678 // Only diagnose if we're shadowing an unambiguous field or variable. 2679 if (R.getResultKind() != LookupResult::Found) 2680 return; 2681 2682 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2683 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2684 return; 2685 2686 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2687 2688 // Only warn about certain kinds of shadowing for class members. 2689 if (NewDC && NewDC->isRecord()) { 2690 // In particular, don't warn about shadowing non-class members. 2691 if (!OldDC->isRecord()) 2692 return; 2693 2694 // TODO: should we warn about static data members shadowing 2695 // static data members from base classes? 2696 2697 // TODO: don't diagnose for inaccessible shadowed members. 2698 // This is hard to do perfectly because we might friend the 2699 // shadowing context, but that's just a false negative. 2700 } 2701 2702 // Determine what kind of declaration we're shadowing. 2703 unsigned Kind; 2704 if (isa<RecordDecl>(OldDC)) { 2705 if (isa<FieldDecl>(ShadowedDecl)) 2706 Kind = 3; // field 2707 else 2708 Kind = 2; // static data member 2709 } else if (OldDC->isFileContext()) 2710 Kind = 1; // global 2711 else 2712 Kind = 0; // local 2713 2714 DeclarationName Name = R.getLookupName(); 2715 2716 // Emit warning and note. 2717 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2718 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2719} 2720 2721/// \brief Check -Wshadow without the advantage of a previous lookup. 2722void Sema::CheckShadow(Scope *S, VarDecl *D) { 2723 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2724 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2725 LookupName(R, S); 2726 CheckShadow(S, D, R); 2727} 2728 2729/// \brief Perform semantic checking on a newly-created variable 2730/// declaration. 2731/// 2732/// This routine performs all of the type-checking required for a 2733/// variable declaration once it has been built. It is used both to 2734/// check variables after they have been parsed and their declarators 2735/// have been translated into a declaration, and to check variables 2736/// that have been instantiated from a template. 2737/// 2738/// Sets NewVD->isInvalidDecl() if an error was encountered. 2739void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2740 LookupResult &Previous, 2741 bool &Redeclaration) { 2742 // If the decl is already known invalid, don't check it. 2743 if (NewVD->isInvalidDecl()) 2744 return; 2745 2746 QualType T = NewVD->getType(); 2747 2748 if (T->isObjCObjectType()) { 2749 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2750 return NewVD->setInvalidDecl(); 2751 } 2752 2753 // Emit an error if an address space was applied to decl with local storage. 2754 // This includes arrays of objects with address space qualifiers, but not 2755 // automatic variables that point to other address spaces. 2756 // ISO/IEC TR 18037 S5.1.2 2757 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2758 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2759 return NewVD->setInvalidDecl(); 2760 } 2761 2762 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2763 && !NewVD->hasAttr<BlocksAttr>()) 2764 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2765 2766 bool isVM = T->isVariablyModifiedType(); 2767 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2768 NewVD->hasAttr<BlocksAttr>() || 2769 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2770 // However, this turns on the scope checker for everything with a variable 2771 // which may impact compile time. See if we can find a better solution 2772 // to this, perhaps only checking functions that contain gotos in C++? 2773 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2774 FunctionNeedsScopeChecking() = true; 2775 2776 if ((isVM && NewVD->hasLinkage()) || 2777 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2778 bool SizeIsNegative; 2779 QualType FixedTy = 2780 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2781 2782 if (FixedTy.isNull() && T->isVariableArrayType()) { 2783 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2784 // FIXME: This won't give the correct result for 2785 // int a[10][n]; 2786 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2787 2788 if (NewVD->isFileVarDecl()) 2789 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2790 << SizeRange; 2791 else if (NewVD->getStorageClass() == VarDecl::Static) 2792 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2793 << SizeRange; 2794 else 2795 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2796 << SizeRange; 2797 return NewVD->setInvalidDecl(); 2798 } 2799 2800 if (FixedTy.isNull()) { 2801 if (NewVD->isFileVarDecl()) 2802 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2803 else 2804 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2805 return NewVD->setInvalidDecl(); 2806 } 2807 2808 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2809 NewVD->setType(FixedTy); 2810 } 2811 2812 if (Previous.empty() && NewVD->isExternC()) { 2813 // Since we did not find anything by this name and we're declaring 2814 // an extern "C" variable, look for a non-visible extern "C" 2815 // declaration with the same name. 2816 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2817 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2818 if (Pos != LocallyScopedExternalDecls.end()) 2819 Previous.addDecl(Pos->second); 2820 } 2821 2822 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2823 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2824 << T; 2825 return NewVD->setInvalidDecl(); 2826 } 2827 2828 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2829 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2830 return NewVD->setInvalidDecl(); 2831 } 2832 2833 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2834 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2835 return NewVD->setInvalidDecl(); 2836 } 2837 2838 if (!Previous.empty()) { 2839 Redeclaration = true; 2840 MergeVarDecl(NewVD, Previous); 2841 } 2842} 2843 2844/// \brief Data used with FindOverriddenMethod 2845struct FindOverriddenMethodData { 2846 Sema *S; 2847 CXXMethodDecl *Method; 2848}; 2849 2850/// \brief Member lookup function that determines whether a given C++ 2851/// method overrides a method in a base class, to be used with 2852/// CXXRecordDecl::lookupInBases(). 2853static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2854 CXXBasePath &Path, 2855 void *UserData) { 2856 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2857 2858 FindOverriddenMethodData *Data 2859 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2860 2861 DeclarationName Name = Data->Method->getDeclName(); 2862 2863 // FIXME: Do we care about other names here too? 2864 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2865 // We really want to find the base class constructor here. 2866 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2867 CanQualType CT = Data->S->Context.getCanonicalType(T); 2868 2869 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2870 } 2871 2872 for (Path.Decls = BaseRecord->lookup(Name); 2873 Path.Decls.first != Path.Decls.second; 2874 ++Path.Decls.first) { 2875 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2876 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2877 return true; 2878 } 2879 } 2880 2881 return false; 2882} 2883 2884/// AddOverriddenMethods - See if a method overrides any in the base classes, 2885/// and if so, check that it's a valid override and remember it. 2886void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2887 // Look for virtual methods in base classes that this method might override. 2888 CXXBasePaths Paths; 2889 FindOverriddenMethodData Data; 2890 Data.Method = MD; 2891 Data.S = this; 2892 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2893 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2894 E = Paths.found_decls_end(); I != E; ++I) { 2895 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2896 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2897 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2898 !CheckOverridingFunctionAttributes(MD, OldMD)) 2899 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2900 } 2901 } 2902 } 2903} 2904 2905NamedDecl* 2906Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2907 QualType R, TypeSourceInfo *TInfo, 2908 LookupResult &Previous, 2909 MultiTemplateParamsArg TemplateParamLists, 2910 bool IsFunctionDefinition, bool &Redeclaration) { 2911 assert(R.getTypePtr()->isFunctionType()); 2912 2913 DeclarationName Name = GetNameForDeclarator(D); 2914 FunctionDecl::StorageClass SC = FunctionDecl::None; 2915 switch (D.getDeclSpec().getStorageClassSpec()) { 2916 default: assert(0 && "Unknown storage class!"); 2917 case DeclSpec::SCS_auto: 2918 case DeclSpec::SCS_register: 2919 case DeclSpec::SCS_mutable: 2920 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2921 diag::err_typecheck_sclass_func); 2922 D.setInvalidType(); 2923 break; 2924 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2925 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2926 case DeclSpec::SCS_static: { 2927 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2928 // C99 6.7.1p5: 2929 // The declaration of an identifier for a function that has 2930 // block scope shall have no explicit storage-class specifier 2931 // other than extern 2932 // See also (C++ [dcl.stc]p4). 2933 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2934 diag::err_static_block_func); 2935 SC = FunctionDecl::None; 2936 } else 2937 SC = FunctionDecl::Static; 2938 break; 2939 } 2940 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2941 } 2942 2943 if (D.getDeclSpec().isThreadSpecified()) 2944 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2945 2946 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2947 bool isInline = D.getDeclSpec().isInlineSpecified(); 2948 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2949 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2950 2951 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2952 FunctionDecl::StorageClass SCAsWritten 2953 = StorageClassSpecToFunctionDeclStorageClass(SCSpec, DC); 2954 2955 // Check that the return type is not an abstract class type. 2956 // For record types, this is done by the AbstractClassUsageDiagnoser once 2957 // the class has been completely parsed. 2958 if (!DC->isRecord() && 2959 RequireNonAbstractType(D.getIdentifierLoc(), 2960 R->getAs<FunctionType>()->getResultType(), 2961 diag::err_abstract_type_in_decl, 2962 AbstractReturnType)) 2963 D.setInvalidType(); 2964 2965 // Do not allow returning a objc interface by-value. 2966 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 2967 Diag(D.getIdentifierLoc(), 2968 diag::err_object_cannot_be_passed_returned_by_value) << 0 2969 << R->getAs<FunctionType>()->getResultType(); 2970 D.setInvalidType(); 2971 } 2972 2973 bool isVirtualOkay = false; 2974 FunctionDecl *NewFD; 2975 2976 if (isFriend) { 2977 // C++ [class.friend]p5 2978 // A function can be defined in a friend declaration of a 2979 // class . . . . Such a function is implicitly inline. 2980 isInline |= IsFunctionDefinition; 2981 } 2982 2983 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2984 // This is a C++ constructor declaration. 2985 assert(DC->isRecord() && 2986 "Constructors can only be declared in a member context"); 2987 2988 R = CheckConstructorDeclarator(D, R, SC); 2989 2990 // Create the new declaration 2991 NewFD = CXXConstructorDecl::Create(Context, 2992 cast<CXXRecordDecl>(DC), 2993 D.getIdentifierLoc(), Name, R, TInfo, 2994 isExplicit, isInline, 2995 /*isImplicitlyDeclared=*/false); 2996 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2997 // This is a C++ destructor declaration. 2998 if (DC->isRecord()) { 2999 R = CheckDestructorDeclarator(D, SC); 3000 3001 NewFD = CXXDestructorDecl::Create(Context, 3002 cast<CXXRecordDecl>(DC), 3003 D.getIdentifierLoc(), Name, R, 3004 isInline, 3005 /*isImplicitlyDeclared=*/false); 3006 NewFD->setTypeSourceInfo(TInfo); 3007 3008 isVirtualOkay = true; 3009 } else { 3010 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3011 3012 // Create a FunctionDecl to satisfy the function definition parsing 3013 // code path. 3014 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3015 Name, R, TInfo, SC, SCAsWritten, isInline, 3016 /*hasPrototype=*/true); 3017 D.setInvalidType(); 3018 } 3019 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3020 if (!DC->isRecord()) { 3021 Diag(D.getIdentifierLoc(), 3022 diag::err_conv_function_not_member); 3023 return 0; 3024 } 3025 3026 CheckConversionDeclarator(D, R, SC); 3027 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3028 D.getIdentifierLoc(), Name, R, TInfo, 3029 isInline, isExplicit); 3030 3031 isVirtualOkay = true; 3032 } else if (DC->isRecord()) { 3033 // If the of the function is the same as the name of the record, then this 3034 // must be an invalid constructor that has a return type. 3035 // (The parser checks for a return type and makes the declarator a 3036 // constructor if it has no return type). 3037 // must have an invalid constructor that has a return type 3038 if (Name.getAsIdentifierInfo() && 3039 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3040 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3041 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3042 << SourceRange(D.getIdentifierLoc()); 3043 return 0; 3044 } 3045 3046 bool isStatic = SC == FunctionDecl::Static; 3047 3048 // [class.free]p1: 3049 // Any allocation function for a class T is a static member 3050 // (even if not explicitly declared static). 3051 if (Name.getCXXOverloadedOperator() == OO_New || 3052 Name.getCXXOverloadedOperator() == OO_Array_New) 3053 isStatic = true; 3054 3055 // [class.free]p6 Any deallocation function for a class X is a static member 3056 // (even if not explicitly declared static). 3057 if (Name.getCXXOverloadedOperator() == OO_Delete || 3058 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3059 isStatic = true; 3060 3061 // This is a C++ method declaration. 3062 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3063 D.getIdentifierLoc(), Name, R, TInfo, 3064 isStatic, SCAsWritten, isInline); 3065 3066 isVirtualOkay = !isStatic; 3067 } else { 3068 // Determine whether the function was written with a 3069 // prototype. This true when: 3070 // - we're in C++ (where every function has a prototype), 3071 // - there is a prototype in the declarator, or 3072 // - the type R of the function is some kind of typedef or other reference 3073 // to a type name (which eventually refers to a function type). 3074 bool HasPrototype = 3075 getLangOptions().CPlusPlus || 3076 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3077 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3078 3079 NewFD = FunctionDecl::Create(Context, DC, 3080 D.getIdentifierLoc(), 3081 Name, R, TInfo, SC, SCAsWritten, isInline, 3082 HasPrototype); 3083 } 3084 3085 if (D.isInvalidType()) 3086 NewFD->setInvalidDecl(); 3087 3088 SetNestedNameSpecifier(NewFD, D); 3089 3090 // Set the lexical context. If the declarator has a C++ 3091 // scope specifier, or is the object of a friend declaration, the 3092 // lexical context will be different from the semantic context. 3093 NewFD->setLexicalDeclContext(CurContext); 3094 3095 // Match up the template parameter lists with the scope specifier, then 3096 // determine whether we have a template or a template specialization. 3097 FunctionTemplateDecl *FunctionTemplate = 0; 3098 bool isExplicitSpecialization = false; 3099 bool isFunctionTemplateSpecialization = false; 3100 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3101 if (TemplateParameterList *TemplateParams 3102 = MatchTemplateParametersToScopeSpecifier( 3103 D.getDeclSpec().getSourceRange().getBegin(), 3104 D.getCXXScopeSpec(), 3105 (TemplateParameterList**)TemplateParamLists.get(), 3106 TemplateParamLists.size(), 3107 isFriend, 3108 isExplicitSpecialization)) { 3109 // All but one template parameter lists have been matching. 3110 --NumMatchedTemplateParamLists; 3111 3112 if (TemplateParams->size() > 0) { 3113 // This is a function template 3114 3115 // Check that we can declare a template here. 3116 if (CheckTemplateDeclScope(S, TemplateParams)) 3117 return 0; 3118 3119 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3120 NewFD->getLocation(), 3121 Name, TemplateParams, 3122 NewFD); 3123 FunctionTemplate->setLexicalDeclContext(CurContext); 3124 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3125 } else { 3126 // This is a function template specialization. 3127 isFunctionTemplateSpecialization = true; 3128 3129 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3130 if (isFriend && isFunctionTemplateSpecialization) { 3131 // We want to remove the "template<>", found here. 3132 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3133 3134 // If we remove the template<> and the name is not a 3135 // template-id, we're actually silently creating a problem: 3136 // the friend declaration will refer to an untemplated decl, 3137 // and clearly the user wants a template specialization. So 3138 // we need to insert '<>' after the name. 3139 SourceLocation InsertLoc; 3140 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3141 InsertLoc = D.getName().getSourceRange().getEnd(); 3142 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3143 } 3144 3145 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3146 << Name << RemoveRange 3147 << FixItHint::CreateRemoval(RemoveRange) 3148 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3149 } 3150 } 3151 } 3152 3153 if (NumMatchedTemplateParamLists > 0) { 3154 NewFD->setTemplateParameterListsInfo(NumMatchedTemplateParamLists, 3155 (TemplateParameterList**)TemplateParamLists.release()); 3156 } 3157 3158 // C++ [dcl.fct.spec]p5: 3159 // The virtual specifier shall only be used in declarations of 3160 // nonstatic class member functions that appear within a 3161 // member-specification of a class declaration; see 10.3. 3162 // 3163 if (isVirtual && !NewFD->isInvalidDecl()) { 3164 if (!isVirtualOkay) { 3165 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3166 diag::err_virtual_non_function); 3167 } else if (!CurContext->isRecord()) { 3168 // 'virtual' was specified outside of the class. 3169 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3170 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3171 } else { 3172 // Okay: Add virtual to the method. 3173 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3174 CurClass->setMethodAsVirtual(NewFD); 3175 } 3176 } 3177 3178 // C++ [dcl.fct.spec]p6: 3179 // The explicit specifier shall be used only in the declaration of a 3180 // constructor or conversion function within its class definition; see 12.3.1 3181 // and 12.3.2. 3182 if (isExplicit && !NewFD->isInvalidDecl()) { 3183 if (!CurContext->isRecord()) { 3184 // 'explicit' was specified outside of the class. 3185 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3186 diag::err_explicit_out_of_class) 3187 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3188 } else if (!isa<CXXConstructorDecl>(NewFD) && 3189 !isa<CXXConversionDecl>(NewFD)) { 3190 // 'explicit' was specified on a function that wasn't a constructor 3191 // or conversion function. 3192 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3193 diag::err_explicit_non_ctor_or_conv_function) 3194 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3195 } 3196 } 3197 3198 // Filter out previous declarations that don't match the scope. 3199 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3200 3201 if (isFriend) { 3202 // DC is the namespace in which the function is being declared. 3203 assert((DC->isFileContext() || !Previous.empty()) && 3204 "previously-undeclared friend function being created " 3205 "in a non-namespace context"); 3206 3207 // For now, claim that the objects have no previous declaration. 3208 if (FunctionTemplate) { 3209 FunctionTemplate->setObjectOfFriendDecl(false); 3210 FunctionTemplate->setAccess(AS_public); 3211 } 3212 NewFD->setObjectOfFriendDecl(false); 3213 NewFD->setAccess(AS_public); 3214 } 3215 3216 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3217 !CurContext->isRecord()) { 3218 // C++ [class.static]p1: 3219 // A data or function member of a class may be declared static 3220 // in a class definition, in which case it is a static member of 3221 // the class. 3222 3223 // Complain about the 'static' specifier if it's on an out-of-line 3224 // member function definition. 3225 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3226 diag::err_static_out_of_line) 3227 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3228 } 3229 3230 // Handle GNU asm-label extension (encoded as an attribute). 3231 if (Expr *E = (Expr*) D.getAsmLabel()) { 3232 // The parser guarantees this is a string. 3233 StringLiteral *SE = cast<StringLiteral>(E); 3234 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3235 } 3236 3237 // Copy the parameter declarations from the declarator D to the function 3238 // declaration NewFD, if they are available. First scavenge them into Params. 3239 llvm::SmallVector<ParmVarDecl*, 16> Params; 3240 if (D.getNumTypeObjects() > 0) { 3241 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3242 3243 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3244 // function that takes no arguments, not a function that takes a 3245 // single void argument. 3246 // We let through "const void" here because Sema::GetTypeForDeclarator 3247 // already checks for that case. 3248 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3249 FTI.ArgInfo[0].Param && 3250 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3251 // Empty arg list, don't push any params. 3252 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3253 3254 // In C++, the empty parameter-type-list must be spelled "void"; a 3255 // typedef of void is not permitted. 3256 if (getLangOptions().CPlusPlus && 3257 Param->getType().getUnqualifiedType() != Context.VoidTy) 3258 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3259 // FIXME: Leaks decl? 3260 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3261 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3262 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3263 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3264 Param->setDeclContext(NewFD); 3265 Params.push_back(Param); 3266 3267 if (Param->isInvalidDecl()) 3268 NewFD->setInvalidDecl(); 3269 } 3270 } 3271 3272 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3273 // When we're declaring a function with a typedef, typeof, etc as in the 3274 // following example, we'll need to synthesize (unnamed) 3275 // parameters for use in the declaration. 3276 // 3277 // @code 3278 // typedef void fn(int); 3279 // fn f; 3280 // @endcode 3281 3282 // Synthesize a parameter for each argument type. 3283 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3284 AE = FT->arg_type_end(); AI != AE; ++AI) { 3285 ParmVarDecl *Param = 3286 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3287 Params.push_back(Param); 3288 } 3289 } else { 3290 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3291 "Should not need args for typedef of non-prototype fn"); 3292 } 3293 // Finally, we know we have the right number of parameters, install them. 3294 NewFD->setParams(Params.data(), Params.size()); 3295 3296 // If the declarator is a template-id, translate the parser's template 3297 // argument list into our AST format. 3298 bool HasExplicitTemplateArgs = false; 3299 TemplateArgumentListInfo TemplateArgs; 3300 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3301 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3302 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3303 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3304 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3305 TemplateId->getTemplateArgs(), 3306 TemplateId->NumArgs); 3307 translateTemplateArguments(TemplateArgsPtr, 3308 TemplateArgs); 3309 TemplateArgsPtr.release(); 3310 3311 HasExplicitTemplateArgs = true; 3312 3313 if (FunctionTemplate) { 3314 // FIXME: Diagnose function template with explicit template 3315 // arguments. 3316 HasExplicitTemplateArgs = false; 3317 } else if (!isFunctionTemplateSpecialization && 3318 !D.getDeclSpec().isFriendSpecified()) { 3319 // We have encountered something that the user meant to be a 3320 // specialization (because it has explicitly-specified template 3321 // arguments) but that was not introduced with a "template<>" (or had 3322 // too few of them). 3323 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3324 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3325 << FixItHint::CreateInsertion( 3326 D.getDeclSpec().getSourceRange().getBegin(), 3327 "template<> "); 3328 isFunctionTemplateSpecialization = true; 3329 } else { 3330 // "friend void foo<>(int);" is an implicit specialization decl. 3331 isFunctionTemplateSpecialization = true; 3332 } 3333 } else if (isFriend && isFunctionTemplateSpecialization) { 3334 // This combination is only possible in a recovery case; the user 3335 // wrote something like: 3336 // template <> friend void foo(int); 3337 // which we're recovering from as if the user had written: 3338 // friend void foo<>(int); 3339 // Go ahead and fake up a template id. 3340 HasExplicitTemplateArgs = true; 3341 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3342 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3343 } 3344 3345 // If it's a friend (and only if it's a friend), it's possible 3346 // that either the specialized function type or the specialized 3347 // template is dependent, and therefore matching will fail. In 3348 // this case, don't check the specialization yet. 3349 if (isFunctionTemplateSpecialization && isFriend && 3350 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3351 assert(HasExplicitTemplateArgs && 3352 "friend function specialization without template args"); 3353 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3354 Previous)) 3355 NewFD->setInvalidDecl(); 3356 } else if (isFunctionTemplateSpecialization) { 3357 if (CheckFunctionTemplateSpecialization(NewFD, 3358 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3359 Previous)) 3360 NewFD->setInvalidDecl(); 3361 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3362 if (CheckMemberSpecialization(NewFD, Previous)) 3363 NewFD->setInvalidDecl(); 3364 } 3365 3366 // Perform semantic checking on the function declaration. 3367 bool OverloadableAttrRequired = false; // FIXME: HACK! 3368 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3369 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3370 3371 assert((NewFD->isInvalidDecl() || !Redeclaration || 3372 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3373 "previous declaration set still overloaded"); 3374 3375 NamedDecl *PrincipalDecl = (FunctionTemplate 3376 ? cast<NamedDecl>(FunctionTemplate) 3377 : NewFD); 3378 3379 if (isFriend && Redeclaration) { 3380 AccessSpecifier Access = AS_public; 3381 if (!NewFD->isInvalidDecl()) 3382 Access = NewFD->getPreviousDeclaration()->getAccess(); 3383 3384 NewFD->setAccess(Access); 3385 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3386 3387 PrincipalDecl->setObjectOfFriendDecl(true); 3388 } 3389 3390 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3391 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3392 PrincipalDecl->setNonMemberOperator(); 3393 3394 // If we have a function template, check the template parameter 3395 // list. This will check and merge default template arguments. 3396 if (FunctionTemplate) { 3397 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3398 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3399 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3400 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3401 : TPC_FunctionTemplate); 3402 } 3403 3404 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3405 // Fake up an access specifier if it's supposed to be a class member. 3406 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3407 NewFD->setAccess(AS_public); 3408 3409 // An out-of-line member function declaration must also be a 3410 // definition (C++ [dcl.meaning]p1). 3411 // Note that this is not the case for explicit specializations of 3412 // function templates or member functions of class templates, per 3413 // C++ [temp.expl.spec]p2. 3414 if (!IsFunctionDefinition && !isFriend && 3415 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3416 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3417 << D.getCXXScopeSpec().getRange(); 3418 NewFD->setInvalidDecl(); 3419 } else if (!Redeclaration && 3420 !(isFriend && CurContext->isDependentContext())) { 3421 // The user tried to provide an out-of-line definition for a 3422 // function that is a member of a class or namespace, but there 3423 // was no such member function declared (C++ [class.mfct]p2, 3424 // C++ [namespace.memdef]p2). For example: 3425 // 3426 // class X { 3427 // void f() const; 3428 // }; 3429 // 3430 // void X::f() { } // ill-formed 3431 // 3432 // Complain about this problem, and attempt to suggest close 3433 // matches (e.g., those that differ only in cv-qualifiers and 3434 // whether the parameter types are references). 3435 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3436 << Name << DC << D.getCXXScopeSpec().getRange(); 3437 NewFD->setInvalidDecl(); 3438 3439 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3440 ForRedeclaration); 3441 LookupQualifiedName(Prev, DC); 3442 assert(!Prev.isAmbiguous() && 3443 "Cannot have an ambiguity in previous-declaration lookup"); 3444 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3445 Func != FuncEnd; ++Func) { 3446 if (isa<FunctionDecl>(*Func) && 3447 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3448 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3449 } 3450 } 3451 } 3452 3453 // Handle attributes. We need to have merged decls when handling attributes 3454 // (for example to check for conflicts, etc). 3455 // FIXME: This needs to happen before we merge declarations. Then, 3456 // let attribute merging cope with attribute conflicts. 3457 ProcessDeclAttributes(S, NewFD, D); 3458 3459 // attributes declared post-definition are currently ignored 3460 if (Redeclaration && Previous.isSingleResult()) { 3461 const FunctionDecl *Def; 3462 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3463 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3464 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3465 Diag(Def->getLocation(), diag::note_previous_definition); 3466 } 3467 } 3468 3469 AddKnownFunctionAttributes(NewFD); 3470 3471 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3472 // If a function name is overloadable in C, then every function 3473 // with that name must be marked "overloadable". 3474 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3475 << Redeclaration << NewFD; 3476 if (!Previous.empty()) 3477 Diag(Previous.getRepresentativeDecl()->getLocation(), 3478 diag::note_attribute_overloadable_prev_overload); 3479 NewFD->addAttr(::new (Context) OverloadableAttr()); 3480 } 3481 3482 // If this is a locally-scoped extern C function, update the 3483 // map of such names. 3484 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3485 && !NewFD->isInvalidDecl()) 3486 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3487 3488 // Set this FunctionDecl's range up to the right paren. 3489 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3490 3491 if (FunctionTemplate && NewFD->isInvalidDecl()) 3492 FunctionTemplate->setInvalidDecl(); 3493 3494 if (FunctionTemplate) 3495 return FunctionTemplate; 3496 3497 3498 // Keep track of static, non-inlined function definitions that 3499 // have not been used. We will warn later. 3500 // FIXME: Also include static functions declared but not defined. 3501 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3502 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3503 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3504 && !NewFD->hasAttr<ConstructorAttr>() 3505 && !NewFD->hasAttr<DestructorAttr>()) 3506 UnusedStaticFuncs.push_back(NewFD); 3507 3508 return NewFD; 3509} 3510 3511/// \brief Perform semantic checking of a new function declaration. 3512/// 3513/// Performs semantic analysis of the new function declaration 3514/// NewFD. This routine performs all semantic checking that does not 3515/// require the actual declarator involved in the declaration, and is 3516/// used both for the declaration of functions as they are parsed 3517/// (called via ActOnDeclarator) and for the declaration of functions 3518/// that have been instantiated via C++ template instantiation (called 3519/// via InstantiateDecl). 3520/// 3521/// \param IsExplicitSpecialiation whether this new function declaration is 3522/// an explicit specialization of the previous declaration. 3523/// 3524/// This sets NewFD->isInvalidDecl() to true if there was an error. 3525void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3526 LookupResult &Previous, 3527 bool IsExplicitSpecialization, 3528 bool &Redeclaration, 3529 bool &OverloadableAttrRequired) { 3530 // If NewFD is already known erroneous, don't do any of this checking. 3531 if (NewFD->isInvalidDecl()) 3532 return; 3533 3534 if (NewFD->getResultType()->isVariablyModifiedType()) { 3535 // Functions returning a variably modified type violate C99 6.7.5.2p2 3536 // because all functions have linkage. 3537 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3538 return NewFD->setInvalidDecl(); 3539 } 3540 3541 if (NewFD->isMain()) 3542 CheckMain(NewFD); 3543 3544 // Check for a previous declaration of this name. 3545 if (Previous.empty() && NewFD->isExternC()) { 3546 // Since we did not find anything by this name and we're declaring 3547 // an extern "C" function, look for a non-visible extern "C" 3548 // declaration with the same name. 3549 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3550 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3551 if (Pos != LocallyScopedExternalDecls.end()) 3552 Previous.addDecl(Pos->second); 3553 } 3554 3555 // Merge or overload the declaration with an existing declaration of 3556 // the same name, if appropriate. 3557 if (!Previous.empty()) { 3558 // Determine whether NewFD is an overload of PrevDecl or 3559 // a declaration that requires merging. If it's an overload, 3560 // there's no more work to do here; we'll just add the new 3561 // function to the scope. 3562 3563 NamedDecl *OldDecl = 0; 3564 if (!AllowOverloadingOfFunction(Previous, Context)) { 3565 Redeclaration = true; 3566 OldDecl = Previous.getFoundDecl(); 3567 } else { 3568 if (!getLangOptions().CPlusPlus) { 3569 OverloadableAttrRequired = true; 3570 3571 // Functions marked "overloadable" must have a prototype (that 3572 // we can't get through declaration merging). 3573 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3574 Diag(NewFD->getLocation(), 3575 diag::err_attribute_overloadable_no_prototype) 3576 << NewFD; 3577 Redeclaration = true; 3578 3579 // Turn this into a variadic function with no parameters. 3580 QualType R = Context.getFunctionType( 3581 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3582 0, 0, true, 0, false, false, 0, 0, 3583 FunctionType::ExtInfo()); 3584 NewFD->setType(R); 3585 return NewFD->setInvalidDecl(); 3586 } 3587 } 3588 3589 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3590 case Ovl_Match: 3591 Redeclaration = true; 3592 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3593 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3594 Redeclaration = false; 3595 } 3596 break; 3597 3598 case Ovl_NonFunction: 3599 Redeclaration = true; 3600 break; 3601 3602 case Ovl_Overload: 3603 Redeclaration = false; 3604 break; 3605 } 3606 } 3607 3608 if (Redeclaration) { 3609 // NewFD and OldDecl represent declarations that need to be 3610 // merged. 3611 if (MergeFunctionDecl(NewFD, OldDecl)) 3612 return NewFD->setInvalidDecl(); 3613 3614 Previous.clear(); 3615 Previous.addDecl(OldDecl); 3616 3617 if (FunctionTemplateDecl *OldTemplateDecl 3618 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3619 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3620 FunctionTemplateDecl *NewTemplateDecl 3621 = NewFD->getDescribedFunctionTemplate(); 3622 assert(NewTemplateDecl && "Template/non-template mismatch"); 3623 if (CXXMethodDecl *Method 3624 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3625 Method->setAccess(OldTemplateDecl->getAccess()); 3626 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3627 } 3628 3629 // If this is an explicit specialization of a member that is a function 3630 // template, mark it as a member specialization. 3631 if (IsExplicitSpecialization && 3632 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3633 NewTemplateDecl->setMemberSpecialization(); 3634 assert(OldTemplateDecl->isMemberSpecialization()); 3635 } 3636 } else { 3637 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3638 NewFD->setAccess(OldDecl->getAccess()); 3639 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3640 } 3641 } 3642 } 3643 3644 // Semantic checking for this function declaration (in isolation). 3645 if (getLangOptions().CPlusPlus) { 3646 // C++-specific checks. 3647 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3648 CheckConstructor(Constructor); 3649 } else if (CXXDestructorDecl *Destructor = 3650 dyn_cast<CXXDestructorDecl>(NewFD)) { 3651 CXXRecordDecl *Record = Destructor->getParent(); 3652 QualType ClassType = Context.getTypeDeclType(Record); 3653 3654 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3655 // type is dependent? Both gcc and edg can handle that. 3656 if (!ClassType->isDependentType()) { 3657 DeclarationName Name 3658 = Context.DeclarationNames.getCXXDestructorName( 3659 Context.getCanonicalType(ClassType)); 3660 if (NewFD->getDeclName() != Name) { 3661 Diag(NewFD->getLocation(), diag::err_destructor_name); 3662 return NewFD->setInvalidDecl(); 3663 } 3664 } 3665 3666 Record->setUserDeclaredDestructor(true); 3667 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3668 // user-defined destructor. 3669 Record->setPOD(false); 3670 3671 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3672 // declared destructor. 3673 // FIXME: C++0x: don't do this for "= default" destructors 3674 Record->setHasTrivialDestructor(false); 3675 } else if (CXXConversionDecl *Conversion 3676 = dyn_cast<CXXConversionDecl>(NewFD)) { 3677 ActOnConversionDeclarator(Conversion); 3678 } 3679 3680 // Find any virtual functions that this function overrides. 3681 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3682 if (!Method->isFunctionTemplateSpecialization() && 3683 !Method->getDescribedFunctionTemplate()) 3684 AddOverriddenMethods(Method->getParent(), Method); 3685 } 3686 3687 // Additional checks for the destructor; make sure we do this after we 3688 // figure out whether the destructor is virtual. 3689 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3690 if (!Destructor->getParent()->isDependentType()) 3691 CheckDestructor(Destructor); 3692 3693 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3694 if (NewFD->isOverloadedOperator() && 3695 CheckOverloadedOperatorDeclaration(NewFD)) 3696 return NewFD->setInvalidDecl(); 3697 3698 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3699 if (NewFD->getLiteralIdentifier() && 3700 CheckLiteralOperatorDeclaration(NewFD)) 3701 return NewFD->setInvalidDecl(); 3702 3703 // In C++, check default arguments now that we have merged decls. Unless 3704 // the lexical context is the class, because in this case this is done 3705 // during delayed parsing anyway. 3706 if (!CurContext->isRecord()) 3707 CheckCXXDefaultArguments(NewFD); 3708 } 3709} 3710 3711void Sema::CheckMain(FunctionDecl* FD) { 3712 // C++ [basic.start.main]p3: A program that declares main to be inline 3713 // or static is ill-formed. 3714 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3715 // shall not appear in a declaration of main. 3716 // static main is not an error under C99, but we should warn about it. 3717 bool isInline = FD->isInlineSpecified(); 3718 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3719 if (isInline || isStatic) { 3720 unsigned diagID = diag::warn_unusual_main_decl; 3721 if (isInline || getLangOptions().CPlusPlus) 3722 diagID = diag::err_unusual_main_decl; 3723 3724 int which = isStatic + (isInline << 1) - 1; 3725 Diag(FD->getLocation(), diagID) << which; 3726 } 3727 3728 QualType T = FD->getType(); 3729 assert(T->isFunctionType() && "function decl is not of function type"); 3730 const FunctionType* FT = T->getAs<FunctionType>(); 3731 3732 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3733 // TODO: add a replacement fixit to turn the return type into 'int'. 3734 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3735 FD->setInvalidDecl(true); 3736 } 3737 3738 // Treat protoless main() as nullary. 3739 if (isa<FunctionNoProtoType>(FT)) return; 3740 3741 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3742 unsigned nparams = FTP->getNumArgs(); 3743 assert(FD->getNumParams() == nparams); 3744 3745 bool HasExtraParameters = (nparams > 3); 3746 3747 // Darwin passes an undocumented fourth argument of type char**. If 3748 // other platforms start sprouting these, the logic below will start 3749 // getting shifty. 3750 if (nparams == 4 && 3751 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3752 HasExtraParameters = false; 3753 3754 if (HasExtraParameters) { 3755 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3756 FD->setInvalidDecl(true); 3757 nparams = 3; 3758 } 3759 3760 // FIXME: a lot of the following diagnostics would be improved 3761 // if we had some location information about types. 3762 3763 QualType CharPP = 3764 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3765 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3766 3767 for (unsigned i = 0; i < nparams; ++i) { 3768 QualType AT = FTP->getArgType(i); 3769 3770 bool mismatch = true; 3771 3772 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3773 mismatch = false; 3774 else if (Expected[i] == CharPP) { 3775 // As an extension, the following forms are okay: 3776 // char const ** 3777 // char const * const * 3778 // char * const * 3779 3780 QualifierCollector qs; 3781 const PointerType* PT; 3782 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3783 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3784 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3785 qs.removeConst(); 3786 mismatch = !qs.empty(); 3787 } 3788 } 3789 3790 if (mismatch) { 3791 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3792 // TODO: suggest replacing given type with expected type 3793 FD->setInvalidDecl(true); 3794 } 3795 } 3796 3797 if (nparams == 1 && !FD->isInvalidDecl()) { 3798 Diag(FD->getLocation(), diag::warn_main_one_arg); 3799 } 3800} 3801 3802bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3803 // FIXME: Need strict checking. In C89, we need to check for 3804 // any assignment, increment, decrement, function-calls, or 3805 // commas outside of a sizeof. In C99, it's the same list, 3806 // except that the aforementioned are allowed in unevaluated 3807 // expressions. Everything else falls under the 3808 // "may accept other forms of constant expressions" exception. 3809 // (We never end up here for C++, so the constant expression 3810 // rules there don't matter.) 3811 if (Init->isConstantInitializer(Context)) 3812 return false; 3813 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3814 << Init->getSourceRange(); 3815 return true; 3816} 3817 3818void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3819 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3820} 3821 3822/// AddInitializerToDecl - Adds the initializer Init to the 3823/// declaration dcl. If DirectInit is true, this is C++ direct 3824/// initialization rather than copy initialization. 3825void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3826 Decl *RealDecl = dcl.getAs<Decl>(); 3827 // If there is no declaration, there was an error parsing it. Just ignore 3828 // the initializer. 3829 if (RealDecl == 0) 3830 return; 3831 3832 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3833 // With declarators parsed the way they are, the parser cannot 3834 // distinguish between a normal initializer and a pure-specifier. 3835 // Thus this grotesque test. 3836 IntegerLiteral *IL; 3837 Expr *Init = static_cast<Expr *>(init.get()); 3838 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3839 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3840 CheckPureMethod(Method, Init->getSourceRange()); 3841 else { 3842 Diag(Method->getLocation(), diag::err_member_function_initialization) 3843 << Method->getDeclName() << Init->getSourceRange(); 3844 Method->setInvalidDecl(); 3845 } 3846 return; 3847 } 3848 3849 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3850 if (!VDecl) { 3851 if (getLangOptions().CPlusPlus && 3852 RealDecl->getLexicalDeclContext()->isRecord() && 3853 isa<NamedDecl>(RealDecl)) 3854 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3855 << cast<NamedDecl>(RealDecl)->getDeclName(); 3856 else 3857 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3858 RealDecl->setInvalidDecl(); 3859 return; 3860 } 3861 3862 // A definition must end up with a complete type, which means it must be 3863 // complete with the restriction that an array type might be completed by the 3864 // initializer; note that later code assumes this restriction. 3865 QualType BaseDeclType = VDecl->getType(); 3866 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3867 BaseDeclType = Array->getElementType(); 3868 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3869 diag::err_typecheck_decl_incomplete_type)) { 3870 RealDecl->setInvalidDecl(); 3871 return; 3872 } 3873 3874 // The variable can not have an abstract class type. 3875 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3876 diag::err_abstract_type_in_decl, 3877 AbstractVariableType)) 3878 VDecl->setInvalidDecl(); 3879 3880 const VarDecl *Def; 3881 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3882 Diag(VDecl->getLocation(), diag::err_redefinition) 3883 << VDecl->getDeclName(); 3884 Diag(Def->getLocation(), diag::note_previous_definition); 3885 VDecl->setInvalidDecl(); 3886 return; 3887 } 3888 3889 // Take ownership of the expression, now that we're sure we have somewhere 3890 // to put it. 3891 Expr *Init = init.takeAs<Expr>(); 3892 assert(Init && "missing initializer"); 3893 3894 // Capture the variable that is being initialized and the style of 3895 // initialization. 3896 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3897 3898 // FIXME: Poor source location information. 3899 InitializationKind Kind 3900 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3901 Init->getLocStart(), 3902 Init->getLocEnd()) 3903 : InitializationKind::CreateCopy(VDecl->getLocation(), 3904 Init->getLocStart()); 3905 3906 // Get the decls type and save a reference for later, since 3907 // CheckInitializerTypes may change it. 3908 QualType DclT = VDecl->getType(), SavT = DclT; 3909 if (VDecl->isBlockVarDecl()) { 3910 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3911 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3912 VDecl->setInvalidDecl(); 3913 } else if (!VDecl->isInvalidDecl()) { 3914 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3915 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3916 MultiExprArg(*this, (void**)&Init, 1), 3917 &DclT); 3918 if (Result.isInvalid()) { 3919 VDecl->setInvalidDecl(); 3920 return; 3921 } 3922 3923 Init = Result.takeAs<Expr>(); 3924 3925 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3926 // Don't check invalid declarations to avoid emitting useless diagnostics. 3927 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3928 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3929 CheckForConstantInitializer(Init, DclT); 3930 } 3931 } 3932 } else if (VDecl->isStaticDataMember() && 3933 VDecl->getLexicalDeclContext()->isRecord()) { 3934 // This is an in-class initialization for a static data member, e.g., 3935 // 3936 // struct S { 3937 // static const int value = 17; 3938 // }; 3939 3940 // Attach the initializer 3941 VDecl->setInit(Init); 3942 3943 // C++ [class.mem]p4: 3944 // A member-declarator can contain a constant-initializer only 3945 // if it declares a static member (9.4) of const integral or 3946 // const enumeration type, see 9.4.2. 3947 QualType T = VDecl->getType(); 3948 if (!T->isDependentType() && 3949 (!Context.getCanonicalType(T).isConstQualified() || 3950 !T->isIntegralType())) { 3951 Diag(VDecl->getLocation(), diag::err_member_initialization) 3952 << VDecl->getDeclName() << Init->getSourceRange(); 3953 VDecl->setInvalidDecl(); 3954 } else { 3955 // C++ [class.static.data]p4: 3956 // If a static data member is of const integral or const 3957 // enumeration type, its declaration in the class definition 3958 // can specify a constant-initializer which shall be an 3959 // integral constant expression (5.19). 3960 if (!Init->isTypeDependent() && 3961 !Init->getType()->isIntegralType()) { 3962 // We have a non-dependent, non-integral or enumeration type. 3963 Diag(Init->getSourceRange().getBegin(), 3964 diag::err_in_class_initializer_non_integral_type) 3965 << Init->getType() << Init->getSourceRange(); 3966 VDecl->setInvalidDecl(); 3967 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3968 // Check whether the expression is a constant expression. 3969 llvm::APSInt Value; 3970 SourceLocation Loc; 3971 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3972 Diag(Loc, diag::err_in_class_initializer_non_constant) 3973 << Init->getSourceRange(); 3974 VDecl->setInvalidDecl(); 3975 } else if (!VDecl->getType()->isDependentType()) 3976 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3977 } 3978 } 3979 } else if (VDecl->isFileVarDecl()) { 3980 if (VDecl->getStorageClass() == VarDecl::Extern && 3981 (!getLangOptions().CPlusPlus || 3982 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 3983 Diag(VDecl->getLocation(), diag::warn_extern_init); 3984 if (!VDecl->isInvalidDecl()) { 3985 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3986 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3987 MultiExprArg(*this, (void**)&Init, 1), 3988 &DclT); 3989 if (Result.isInvalid()) { 3990 VDecl->setInvalidDecl(); 3991 return; 3992 } 3993 3994 Init = Result.takeAs<Expr>(); 3995 } 3996 3997 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3998 // Don't check invalid declarations to avoid emitting useless diagnostics. 3999 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4000 // C99 6.7.8p4. All file scoped initializers need to be constant. 4001 CheckForConstantInitializer(Init, DclT); 4002 } 4003 } 4004 // If the type changed, it means we had an incomplete type that was 4005 // completed by the initializer. For example: 4006 // int ary[] = { 1, 3, 5 }; 4007 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4008 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4009 VDecl->setType(DclT); 4010 Init->setType(DclT); 4011 } 4012 4013 Init = MaybeCreateCXXExprWithTemporaries(Init); 4014 // Attach the initializer to the decl. 4015 VDecl->setInit(Init); 4016 4017 if (getLangOptions().CPlusPlus) { 4018 // Make sure we mark the destructor as used if necessary. 4019 QualType InitType = VDecl->getType(); 4020 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4021 InitType = Context.getBaseElementType(Array); 4022 if (const RecordType *Record = InitType->getAs<RecordType>()) 4023 FinalizeVarWithDestructor(VDecl, Record); 4024 } 4025 4026 return; 4027} 4028 4029/// ActOnInitializerError - Given that there was an error parsing an 4030/// initializer for the given declaration, try to return to some form 4031/// of sanity. 4032void Sema::ActOnInitializerError(DeclPtrTy dcl) { 4033 // Our main concern here is re-establishing invariants like "a 4034 // variable's type is either dependent or complete". 4035 Decl *D = dcl.getAs<Decl>(); 4036 if (!D || D->isInvalidDecl()) return; 4037 4038 VarDecl *VD = dyn_cast<VarDecl>(D); 4039 if (!VD) return; 4040 4041 QualType Ty = VD->getType(); 4042 if (Ty->isDependentType()) return; 4043 4044 // Require a complete type. 4045 if (RequireCompleteType(VD->getLocation(), 4046 Context.getBaseElementType(Ty), 4047 diag::err_typecheck_decl_incomplete_type)) { 4048 VD->setInvalidDecl(); 4049 return; 4050 } 4051 4052 // Require an abstract type. 4053 if (RequireNonAbstractType(VD->getLocation(), Ty, 4054 diag::err_abstract_type_in_decl, 4055 AbstractVariableType)) { 4056 VD->setInvalidDecl(); 4057 return; 4058 } 4059 4060 // Don't bother complaining about constructors or destructors, 4061 // though. 4062} 4063 4064void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 4065 bool TypeContainsUndeducedAuto) { 4066 Decl *RealDecl = dcl.getAs<Decl>(); 4067 4068 // If there is no declaration, there was an error parsing it. Just ignore it. 4069 if (RealDecl == 0) 4070 return; 4071 4072 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4073 QualType Type = Var->getType(); 4074 4075 // C++0x [dcl.spec.auto]p3 4076 if (TypeContainsUndeducedAuto) { 4077 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4078 << Var->getDeclName() << Type; 4079 Var->setInvalidDecl(); 4080 return; 4081 } 4082 4083 switch (Var->isThisDeclarationADefinition()) { 4084 case VarDecl::Definition: 4085 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4086 break; 4087 4088 // We have an out-of-line definition of a static data member 4089 // that has an in-class initializer, so we type-check this like 4090 // a declaration. 4091 // 4092 // Fall through 4093 4094 case VarDecl::DeclarationOnly: 4095 // It's only a declaration. 4096 4097 // Block scope. C99 6.7p7: If an identifier for an object is 4098 // declared with no linkage (C99 6.2.2p6), the type for the 4099 // object shall be complete. 4100 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4101 !Var->getLinkage() && !Var->isInvalidDecl() && 4102 RequireCompleteType(Var->getLocation(), Type, 4103 diag::err_typecheck_decl_incomplete_type)) 4104 Var->setInvalidDecl(); 4105 4106 // Make sure that the type is not abstract. 4107 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4108 RequireNonAbstractType(Var->getLocation(), Type, 4109 diag::err_abstract_type_in_decl, 4110 AbstractVariableType)) 4111 Var->setInvalidDecl(); 4112 return; 4113 4114 case VarDecl::TentativeDefinition: 4115 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4116 // object that has file scope without an initializer, and without a 4117 // storage-class specifier or with the storage-class specifier "static", 4118 // constitutes a tentative definition. Note: A tentative definition with 4119 // external linkage is valid (C99 6.2.2p5). 4120 if (!Var->isInvalidDecl()) { 4121 if (const IncompleteArrayType *ArrayT 4122 = Context.getAsIncompleteArrayType(Type)) { 4123 if (RequireCompleteType(Var->getLocation(), 4124 ArrayT->getElementType(), 4125 diag::err_illegal_decl_array_incomplete_type)) 4126 Var->setInvalidDecl(); 4127 } else if (Var->getStorageClass() == VarDecl::Static) { 4128 // C99 6.9.2p3: If the declaration of an identifier for an object is 4129 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4130 // declared type shall not be an incomplete type. 4131 // NOTE: code such as the following 4132 // static struct s; 4133 // struct s { int a; }; 4134 // is accepted by gcc. Hence here we issue a warning instead of 4135 // an error and we do not invalidate the static declaration. 4136 // NOTE: to avoid multiple warnings, only check the first declaration. 4137 if (Var->getPreviousDeclaration() == 0) 4138 RequireCompleteType(Var->getLocation(), Type, 4139 diag::ext_typecheck_decl_incomplete_type); 4140 } 4141 } 4142 4143 // Record the tentative definition; we're done. 4144 if (!Var->isInvalidDecl()) 4145 TentativeDefinitions.push_back(Var); 4146 return; 4147 } 4148 4149 // Provide a specific diagnostic for uninitialized variable 4150 // definitions with incomplete array type. 4151 if (Type->isIncompleteArrayType()) { 4152 Diag(Var->getLocation(), 4153 diag::err_typecheck_incomplete_array_needs_initializer); 4154 Var->setInvalidDecl(); 4155 return; 4156 } 4157 4158 // Provide a specific diagnostic for uninitialized variable 4159 // definitions with reference type. 4160 if (Type->isReferenceType()) { 4161 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4162 << Var->getDeclName() 4163 << SourceRange(Var->getLocation(), Var->getLocation()); 4164 Var->setInvalidDecl(); 4165 return; 4166 } 4167 4168 // Do not attempt to type-check the default initializer for a 4169 // variable with dependent type. 4170 if (Type->isDependentType()) 4171 return; 4172 4173 if (Var->isInvalidDecl()) 4174 return; 4175 4176 if (RequireCompleteType(Var->getLocation(), 4177 Context.getBaseElementType(Type), 4178 diag::err_typecheck_decl_incomplete_type)) { 4179 Var->setInvalidDecl(); 4180 return; 4181 } 4182 4183 // The variable can not have an abstract class type. 4184 if (RequireNonAbstractType(Var->getLocation(), Type, 4185 diag::err_abstract_type_in_decl, 4186 AbstractVariableType)) { 4187 Var->setInvalidDecl(); 4188 return; 4189 } 4190 4191 const RecordType *Record 4192 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4193 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4194 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4195 // C++03 [dcl.init]p9: 4196 // If no initializer is specified for an object, and the 4197 // object is of (possibly cv-qualified) non-POD class type (or 4198 // array thereof), the object shall be default-initialized; if 4199 // the object is of const-qualified type, the underlying class 4200 // type shall have a user-declared default 4201 // constructor. Otherwise, if no initializer is specified for 4202 // a non- static object, the object and its subobjects, if 4203 // any, have an indeterminate initial value); if the object 4204 // or any of its subobjects are of const-qualified type, the 4205 // program is ill-formed. 4206 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4207 } else { 4208 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4209 InitializationKind Kind 4210 = InitializationKind::CreateDefault(Var->getLocation()); 4211 4212 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4213 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4214 MultiExprArg(*this, 0, 0)); 4215 if (Init.isInvalid()) 4216 Var->setInvalidDecl(); 4217 else if (Init.get()) 4218 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4219 } 4220 4221 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4222 FinalizeVarWithDestructor(Var, Record); 4223 } 4224} 4225 4226Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4227 DeclPtrTy *Group, 4228 unsigned NumDecls) { 4229 llvm::SmallVector<Decl*, 8> Decls; 4230 4231 if (DS.isTypeSpecOwned()) 4232 Decls.push_back((Decl*)DS.getTypeRep()); 4233 4234 for (unsigned i = 0; i != NumDecls; ++i) 4235 if (Decl *D = Group[i].getAs<Decl>()) 4236 Decls.push_back(D); 4237 4238 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4239 Decls.data(), Decls.size())); 4240} 4241 4242 4243/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4244/// to introduce parameters into function prototype scope. 4245Sema::DeclPtrTy 4246Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4247 const DeclSpec &DS = D.getDeclSpec(); 4248 4249 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4250 VarDecl::StorageClass StorageClass = VarDecl::None; 4251 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4252 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4253 StorageClass = VarDecl::Register; 4254 StorageClassAsWritten = VarDecl::Register; 4255 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4256 Diag(DS.getStorageClassSpecLoc(), 4257 diag::err_invalid_storage_class_in_func_decl); 4258 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4259 } 4260 4261 if (D.getDeclSpec().isThreadSpecified()) 4262 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4263 4264 DiagnoseFunctionSpecifiers(D); 4265 4266 // Check that there are no default arguments inside the type of this 4267 // parameter (C++ only). 4268 if (getLangOptions().CPlusPlus) 4269 CheckExtraCXXDefaultArguments(D); 4270 4271 TagDecl *OwnedDecl = 0; 4272 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4273 QualType parmDeclType = TInfo->getType(); 4274 4275 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4276 // C++ [dcl.fct]p6: 4277 // Types shall not be defined in return or parameter types. 4278 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4279 << Context.getTypeDeclType(OwnedDecl); 4280 } 4281 4282 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4283 IdentifierInfo *II = D.getIdentifier(); 4284 if (II) { 4285 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4286 ForRedeclaration); 4287 LookupName(R, S); 4288 if (R.isSingleResult()) { 4289 NamedDecl *PrevDecl = R.getFoundDecl(); 4290 if (PrevDecl->isTemplateParameter()) { 4291 // Maybe we will complain about the shadowed template parameter. 4292 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4293 // Just pretend that we didn't see the previous declaration. 4294 PrevDecl = 0; 4295 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4296 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4297 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4298 4299 // Recover by removing the name 4300 II = 0; 4301 D.SetIdentifier(0, D.getIdentifierLoc()); 4302 D.setInvalidType(true); 4303 } 4304 } 4305 } 4306 4307 // Temporarily put parameter variables in the translation unit, not 4308 // the enclosing context. This prevents them from accidentally 4309 // looking like class members in C++. 4310 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4311 TInfo, parmDeclType, II, 4312 D.getIdentifierLoc(), 4313 StorageClass, StorageClassAsWritten); 4314 4315 if (D.isInvalidType()) 4316 New->setInvalidDecl(); 4317 4318 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4319 if (D.getCXXScopeSpec().isSet()) { 4320 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4321 << D.getCXXScopeSpec().getRange(); 4322 New->setInvalidDecl(); 4323 } 4324 4325 // Add the parameter declaration into this scope. 4326 S->AddDecl(DeclPtrTy::make(New)); 4327 if (II) 4328 IdResolver.AddDecl(New); 4329 4330 ProcessDeclAttributes(S, New, D); 4331 4332 if (New->hasAttr<BlocksAttr>()) { 4333 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4334 } 4335 return DeclPtrTy::make(New); 4336} 4337 4338/// \brief Synthesizes a variable for a parameter arising from a 4339/// typedef. 4340ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4341 SourceLocation Loc, 4342 QualType T) { 4343 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4344 T, Context.getTrivialTypeSourceInfo(T, Loc), 4345 VarDecl::None, VarDecl::None, 0); 4346 Param->setImplicit(); 4347 return Param; 4348} 4349 4350ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4351 TypeSourceInfo *TSInfo, QualType T, 4352 IdentifierInfo *Name, 4353 SourceLocation NameLoc, 4354 VarDecl::StorageClass StorageClass, 4355 VarDecl::StorageClass StorageClassAsWritten) { 4356 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4357 adjustParameterType(T), TSInfo, 4358 StorageClass, StorageClassAsWritten, 4359 0); 4360 4361 // Parameters can not be abstract class types. 4362 // For record types, this is done by the AbstractClassUsageDiagnoser once 4363 // the class has been completely parsed. 4364 if (!CurContext->isRecord() && 4365 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4366 AbstractParamType)) 4367 New->setInvalidDecl(); 4368 4369 // Parameter declarators cannot be interface types. All ObjC objects are 4370 // passed by reference. 4371 if (T->isObjCObjectType()) { 4372 Diag(NameLoc, 4373 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4374 New->setInvalidDecl(); 4375 } 4376 4377 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4378 // duration shall not be qualified by an address-space qualifier." 4379 // Since all parameters have automatic store duration, they can not have 4380 // an address space. 4381 if (T.getAddressSpace() != 0) { 4382 Diag(NameLoc, diag::err_arg_with_address_space); 4383 New->setInvalidDecl(); 4384 } 4385 4386 return New; 4387} 4388 4389void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4390 SourceLocation LocAfterDecls) { 4391 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4392 "Not a function declarator!"); 4393 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4394 4395 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4396 // for a K&R function. 4397 if (!FTI.hasPrototype) { 4398 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4399 --i; 4400 if (FTI.ArgInfo[i].Param == 0) { 4401 llvm::SmallString<256> Code; 4402 llvm::raw_svector_ostream(Code) << " int " 4403 << FTI.ArgInfo[i].Ident->getName() 4404 << ";\n"; 4405 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4406 << FTI.ArgInfo[i].Ident 4407 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4408 4409 // Implicitly declare the argument as type 'int' for lack of a better 4410 // type. 4411 DeclSpec DS; 4412 const char* PrevSpec; // unused 4413 unsigned DiagID; // unused 4414 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4415 PrevSpec, DiagID); 4416 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4417 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4418 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4419 } 4420 } 4421 } 4422} 4423 4424Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4425 Declarator &D) { 4426 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4427 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4428 "Not a function declarator!"); 4429 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4430 4431 if (FTI.hasPrototype) { 4432 // FIXME: Diagnose arguments without names in C. 4433 } 4434 4435 Scope *ParentScope = FnBodyScope->getParent(); 4436 4437 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4438 MultiTemplateParamsArg(*this), 4439 /*IsFunctionDefinition=*/true); 4440 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4441} 4442 4443static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4444 // Don't warn about invalid declarations. 4445 if (FD->isInvalidDecl()) 4446 return false; 4447 4448 // Or declarations that aren't global. 4449 if (!FD->isGlobal()) 4450 return false; 4451 4452 // Don't warn about C++ member functions. 4453 if (isa<CXXMethodDecl>(FD)) 4454 return false; 4455 4456 // Don't warn about 'main'. 4457 if (FD->isMain()) 4458 return false; 4459 4460 // Don't warn about inline functions. 4461 if (FD->isInlineSpecified()) 4462 return false; 4463 4464 // Don't warn about function templates. 4465 if (FD->getDescribedFunctionTemplate()) 4466 return false; 4467 4468 // Don't warn about function template specializations. 4469 if (FD->isFunctionTemplateSpecialization()) 4470 return false; 4471 4472 bool MissingPrototype = true; 4473 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4474 Prev; Prev = Prev->getPreviousDeclaration()) { 4475 // Ignore any declarations that occur in function or method 4476 // scope, because they aren't visible from the header. 4477 if (Prev->getDeclContext()->isFunctionOrMethod()) 4478 continue; 4479 4480 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4481 break; 4482 } 4483 4484 return MissingPrototype; 4485} 4486 4487Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4488 // Clear the last template instantiation error context. 4489 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4490 4491 if (!D) 4492 return D; 4493 FunctionDecl *FD = 0; 4494 4495 if (FunctionTemplateDecl *FunTmpl 4496 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4497 FD = FunTmpl->getTemplatedDecl(); 4498 else 4499 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4500 4501 // Enter a new function scope 4502 PushFunctionScope(); 4503 4504 // See if this is a redefinition. 4505 // But don't complain if we're in GNU89 mode and the previous definition 4506 // was an extern inline function. 4507 const FunctionDecl *Definition; 4508 if (FD->getBody(Definition) && 4509 !canRedefineFunction(Definition, getLangOptions())) { 4510 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4511 Diag(Definition->getLocation(), diag::note_previous_definition); 4512 } 4513 4514 // Builtin functions cannot be defined. 4515 if (unsigned BuiltinID = FD->getBuiltinID()) { 4516 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4517 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4518 FD->setInvalidDecl(); 4519 } 4520 } 4521 4522 // The return type of a function definition must be complete 4523 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4524 QualType ResultType = FD->getResultType(); 4525 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4526 !FD->isInvalidDecl() && 4527 RequireCompleteType(FD->getLocation(), ResultType, 4528 diag::err_func_def_incomplete_result)) 4529 FD->setInvalidDecl(); 4530 4531 // GNU warning -Wmissing-prototypes: 4532 // Warn if a global function is defined without a previous 4533 // prototype declaration. This warning is issued even if the 4534 // definition itself provides a prototype. The aim is to detect 4535 // global functions that fail to be declared in header files. 4536 if (ShouldWarnAboutMissingPrototype(FD)) 4537 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4538 4539 if (FnBodyScope) 4540 PushDeclContext(FnBodyScope, FD); 4541 4542 // Check the validity of our function parameters 4543 CheckParmsForFunctionDef(FD); 4544 4545 bool ShouldCheckShadow = 4546 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4547 4548 // Introduce our parameters into the function scope 4549 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4550 ParmVarDecl *Param = FD->getParamDecl(p); 4551 Param->setOwningFunction(FD); 4552 4553 // If this has an identifier, add it to the scope stack. 4554 if (Param->getIdentifier() && FnBodyScope) { 4555 if (ShouldCheckShadow) 4556 CheckShadow(FnBodyScope, Param); 4557 4558 PushOnScopeChains(Param, FnBodyScope); 4559 } 4560 } 4561 4562 // Checking attributes of current function definition 4563 // dllimport attribute. 4564 if (FD->getAttr<DLLImportAttr>() && 4565 (!FD->getAttr<DLLExportAttr>())) { 4566 // dllimport attribute cannot be applied to definition. 4567 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4568 Diag(FD->getLocation(), 4569 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4570 << "dllimport"; 4571 FD->setInvalidDecl(); 4572 return DeclPtrTy::make(FD); 4573 } 4574 4575 // Visual C++ appears to not think this is an issue, so only issue 4576 // a warning when Microsoft extensions are disabled. 4577 if (!LangOpts.Microsoft) { 4578 // If a symbol previously declared dllimport is later defined, the 4579 // attribute is ignored in subsequent references, and a warning is 4580 // emitted. 4581 Diag(FD->getLocation(), 4582 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4583 << FD->getNameAsCString() << "dllimport"; 4584 } 4585 } 4586 return DeclPtrTy::make(FD); 4587} 4588 4589/// \brief Given the set of return statements within a function body, 4590/// compute the variables that are subject to the named return value 4591/// optimization. 4592/// 4593/// Each of the variables that is subject to the named return value 4594/// optimization will be marked as NRVO variables in the AST, and any 4595/// return statement that has a marked NRVO variable as its NRVO candidate can 4596/// use the named return value optimization. 4597/// 4598/// This function applies a very simplistic algorithm for NRVO: if every return 4599/// statement in the function has the same NRVO candidate, that candidate is 4600/// the NRVO variable. 4601/// 4602/// FIXME: Employ a smarter algorithm that accounts for multiple return 4603/// statements and the lifetimes of the NRVO candidates. We should be able to 4604/// find a maximal set of NRVO variables. 4605static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4606 const VarDecl *NRVOCandidate = 0; 4607 for (unsigned I = 0; I != NumReturns; ++I) { 4608 if (!Returns[I]->getNRVOCandidate()) 4609 return; 4610 4611 if (!NRVOCandidate) 4612 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4613 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4614 return; 4615 } 4616 4617 if (NRVOCandidate) 4618 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4619} 4620 4621Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4622 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4623} 4624 4625Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4626 bool IsInstantiation) { 4627 Decl *dcl = D.getAs<Decl>(); 4628 Stmt *Body = BodyArg.takeAs<Stmt>(); 4629 4630 FunctionDecl *FD = 0; 4631 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4632 if (FunTmpl) 4633 FD = FunTmpl->getTemplatedDecl(); 4634 else 4635 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4636 4637 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4638 4639 if (FD) { 4640 FD->setBody(Body); 4641 if (FD->isMain()) { 4642 // C and C++ allow for main to automagically return 0. 4643 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4644 FD->setHasImplicitReturnZero(true); 4645 WP.disableCheckFallThrough(); 4646 } 4647 4648 if (!FD->isInvalidDecl()) { 4649 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4650 4651 // If this is a constructor, we need a vtable. 4652 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4653 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4654 4655 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4656 FunctionScopes.back()->Returns.size()); 4657 } 4658 4659 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4660 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4661 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4662 MD->setBody(Body); 4663 MD->setEndLoc(Body->getLocEnd()); 4664 if (!MD->isInvalidDecl()) 4665 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4666 } else { 4667 Body->Destroy(Context); 4668 return DeclPtrTy(); 4669 } 4670 4671 // Verify and clean out per-function state. 4672 4673 // Check goto/label use. 4674 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4675 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4676 LabelStmt *L = I->second; 4677 4678 // Verify that we have no forward references left. If so, there was a goto 4679 // or address of a label taken, but no definition of it. Label fwd 4680 // definitions are indicated with a null substmt. 4681 if (L->getSubStmt() != 0) 4682 continue; 4683 4684 // Emit error. 4685 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4686 4687 // At this point, we have gotos that use the bogus label. Stitch it into 4688 // the function body so that they aren't leaked and that the AST is well 4689 // formed. 4690 if (Body == 0) { 4691 // The whole function wasn't parsed correctly, just delete this. 4692 L->Destroy(Context); 4693 continue; 4694 } 4695 4696 // Otherwise, the body is valid: we want to stitch the label decl into the 4697 // function somewhere so that it is properly owned and so that the goto 4698 // has a valid target. Do this by creating a new compound stmt with the 4699 // label in it. 4700 4701 // Give the label a sub-statement. 4702 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4703 4704 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4705 cast<CXXTryStmt>(Body)->getTryBlock() : 4706 cast<CompoundStmt>(Body); 4707 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4708 Compound->body_end()); 4709 Elements.push_back(L); 4710 Compound->setStmts(Context, Elements.data(), Elements.size()); 4711 } 4712 4713 if (Body) { 4714 // C++ constructors that have function-try-blocks can't have return 4715 // statements in the handlers of that block. (C++ [except.handle]p14) 4716 // Verify this. 4717 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4718 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4719 4720 // Verify that that gotos and switch cases don't jump into scopes illegally. 4721 // Verify that that gotos and switch cases don't jump into scopes illegally. 4722 if (FunctionNeedsScopeChecking() && 4723 !dcl->isInvalidDecl() && 4724 !hasAnyErrorsInThisFunction()) 4725 DiagnoseInvalidJumps(Body); 4726 4727 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4728 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4729 Destructor->getParent()); 4730 4731 // If any errors have occurred, clear out any temporaries that may have 4732 // been leftover. This ensures that these temporaries won't be picked up for 4733 // deletion in some later function. 4734 if (PP.getDiagnostics().hasErrorOccurred()) 4735 ExprTemporaries.clear(); 4736 else if (!isa<FunctionTemplateDecl>(dcl)) { 4737 // Since the body is valid, issue any analysis-based warnings that are 4738 // enabled. 4739 QualType ResultType; 4740 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4741 ResultType = FD->getResultType(); 4742 } 4743 else { 4744 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4745 ResultType = MD->getResultType(); 4746 } 4747 AnalysisWarnings.IssueWarnings(WP, dcl); 4748 } 4749 4750 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4751 } 4752 4753 if (!IsInstantiation) 4754 PopDeclContext(); 4755 4756 PopFunctionOrBlockScope(); 4757 4758 // If any errors have occurred, clear out any temporaries that may have 4759 // been leftover. This ensures that these temporaries won't be picked up for 4760 // deletion in some later function. 4761 if (getDiagnostics().hasErrorOccurred()) 4762 ExprTemporaries.clear(); 4763 4764 return D; 4765} 4766 4767/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4768/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4769NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4770 IdentifierInfo &II, Scope *S) { 4771 // Before we produce a declaration for an implicitly defined 4772 // function, see whether there was a locally-scoped declaration of 4773 // this name as a function or variable. If so, use that 4774 // (non-visible) declaration, and complain about it. 4775 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4776 = LocallyScopedExternalDecls.find(&II); 4777 if (Pos != LocallyScopedExternalDecls.end()) { 4778 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4779 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4780 return Pos->second; 4781 } 4782 4783 // Extension in C99. Legal in C90, but warn about it. 4784 if (II.getName().startswith("__builtin_")) 4785 Diag(Loc, diag::warn_builtin_unknown) << &II; 4786 else if (getLangOptions().C99) 4787 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4788 else 4789 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4790 4791 // Set a Declarator for the implicit definition: int foo(); 4792 const char *Dummy; 4793 DeclSpec DS; 4794 unsigned DiagID; 4795 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4796 Error = Error; // Silence warning. 4797 assert(!Error && "Error setting up implicit decl!"); 4798 Declarator D(DS, Declarator::BlockContext); 4799 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4800 0, 0, false, SourceLocation(), 4801 false, 0,0,0, Loc, Loc, D), 4802 SourceLocation()); 4803 D.SetIdentifier(&II, Loc); 4804 4805 // Insert this function into translation-unit scope. 4806 4807 DeclContext *PrevDC = CurContext; 4808 CurContext = Context.getTranslationUnitDecl(); 4809 4810 FunctionDecl *FD = 4811 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4812 FD->setImplicit(); 4813 4814 CurContext = PrevDC; 4815 4816 AddKnownFunctionAttributes(FD); 4817 4818 return FD; 4819} 4820 4821/// \brief Adds any function attributes that we know a priori based on 4822/// the declaration of this function. 4823/// 4824/// These attributes can apply both to implicitly-declared builtins 4825/// (like __builtin___printf_chk) or to library-declared functions 4826/// like NSLog or printf. 4827void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4828 if (FD->isInvalidDecl()) 4829 return; 4830 4831 // If this is a built-in function, map its builtin attributes to 4832 // actual attributes. 4833 if (unsigned BuiltinID = FD->getBuiltinID()) { 4834 // Handle printf-formatting attributes. 4835 unsigned FormatIdx; 4836 bool HasVAListArg; 4837 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4838 if (!FD->getAttr<FormatAttr>()) 4839 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4840 HasVAListArg ? 0 : FormatIdx+2)); 4841 } 4842 4843 // Mark const if we don't care about errno and that is the only 4844 // thing preventing the function from being const. This allows 4845 // IRgen to use LLVM intrinsics for such functions. 4846 if (!getLangOptions().MathErrno && 4847 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4848 if (!FD->getAttr<ConstAttr>()) 4849 FD->addAttr(::new (Context) ConstAttr()); 4850 } 4851 4852 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4853 FD->setType(Context.getNoReturnType(FD->getType())); 4854 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4855 FD->addAttr(::new (Context) NoThrowAttr()); 4856 if (Context.BuiltinInfo.isConst(BuiltinID)) 4857 FD->addAttr(::new (Context) ConstAttr()); 4858 } 4859 4860 IdentifierInfo *Name = FD->getIdentifier(); 4861 if (!Name) 4862 return; 4863 if ((!getLangOptions().CPlusPlus && 4864 FD->getDeclContext()->isTranslationUnit()) || 4865 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4866 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4867 LinkageSpecDecl::lang_c)) { 4868 // Okay: this could be a libc/libm/Objective-C function we know 4869 // about. 4870 } else 4871 return; 4872 4873 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4874 // FIXME: NSLog and NSLogv should be target specific 4875 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4876 // FIXME: We known better than our headers. 4877 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4878 } else 4879 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4880 Name->isStr("NSLogv") ? 0 : 2)); 4881 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4882 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4883 // target-specific builtins, perhaps? 4884 if (!FD->getAttr<FormatAttr>()) 4885 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4886 Name->isStr("vasprintf") ? 0 : 3)); 4887 } 4888} 4889 4890TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4891 TypeSourceInfo *TInfo) { 4892 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4893 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4894 4895 if (!TInfo) { 4896 assert(D.isInvalidType() && "no declarator info for valid type"); 4897 TInfo = Context.getTrivialTypeSourceInfo(T); 4898 } 4899 4900 // Scope manipulation handled by caller. 4901 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4902 D.getIdentifierLoc(), 4903 D.getIdentifier(), 4904 TInfo); 4905 4906 if (const TagType *TT = T->getAs<TagType>()) { 4907 TagDecl *TD = TT->getDecl(); 4908 4909 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4910 // keep track of the TypedefDecl. 4911 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4912 TD->setTypedefForAnonDecl(NewTD); 4913 } 4914 4915 if (D.isInvalidType()) 4916 NewTD->setInvalidDecl(); 4917 return NewTD; 4918} 4919 4920 4921/// \brief Determine whether a tag with a given kind is acceptable 4922/// as a redeclaration of the given tag declaration. 4923/// 4924/// \returns true if the new tag kind is acceptable, false otherwise. 4925bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4926 TagTypeKind NewTag, 4927 SourceLocation NewTagLoc, 4928 const IdentifierInfo &Name) { 4929 // C++ [dcl.type.elab]p3: 4930 // The class-key or enum keyword present in the 4931 // elaborated-type-specifier shall agree in kind with the 4932 // declaration to which the name in the elaborated-type-specifier 4933 // refers. This rule also applies to the form of 4934 // elaborated-type-specifier that declares a class-name or 4935 // friend class since it can be construed as referring to the 4936 // definition of the class. Thus, in any 4937 // elaborated-type-specifier, the enum keyword shall be used to 4938 // refer to an enumeration (7.2), the union class-key shall be 4939 // used to refer to a union (clause 9), and either the class or 4940 // struct class-key shall be used to refer to a class (clause 9) 4941 // declared using the class or struct class-key. 4942 TagTypeKind OldTag = Previous->getTagKind(); 4943 if (OldTag == NewTag) 4944 return true; 4945 4946 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 4947 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 4948 // Warn about the struct/class tag mismatch. 4949 bool isTemplate = false; 4950 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4951 isTemplate = Record->getDescribedClassTemplate(); 4952 4953 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4954 << (NewTag == TTK_Class) 4955 << isTemplate << &Name 4956 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 4957 OldTag == TTK_Class? "class" : "struct"); 4958 Diag(Previous->getLocation(), diag::note_previous_use); 4959 return true; 4960 } 4961 return false; 4962} 4963 4964/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4965/// former case, Name will be non-null. In the later case, Name will be null. 4966/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4967/// reference/declaration/definition of a tag. 4968Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4969 SourceLocation KWLoc, CXXScopeSpec &SS, 4970 IdentifierInfo *Name, SourceLocation NameLoc, 4971 AttributeList *Attr, AccessSpecifier AS, 4972 MultiTemplateParamsArg TemplateParameterLists, 4973 bool &OwnedDecl, bool &IsDependent) { 4974 // If this is not a definition, it must have a name. 4975 assert((Name != 0 || TUK == TUK_Definition) && 4976 "Nameless record must be a definition!"); 4977 4978 OwnedDecl = false; 4979 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 4980 4981 // FIXME: Check explicit specializations more carefully. 4982 bool isExplicitSpecialization = false; 4983 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 4984 if (TUK != TUK_Reference) { 4985 if (TemplateParameterList *TemplateParams 4986 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4987 (TemplateParameterList**)TemplateParameterLists.get(), 4988 TemplateParameterLists.size(), 4989 TUK == TUK_Friend, 4990 isExplicitSpecialization)) { 4991 // All but one template parameter lists have been matching. 4992 --NumMatchedTemplateParamLists; 4993 4994 if (TemplateParams->size() > 0) { 4995 // This is a declaration or definition of a class template (which may 4996 // be a member of another template). 4997 OwnedDecl = false; 4998 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4999 SS, Name, NameLoc, Attr, 5000 TemplateParams, 5001 AS); 5002 TemplateParameterLists.release(); 5003 return Result.get(); 5004 } else { 5005 // The "template<>" header is extraneous. 5006 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5007 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5008 isExplicitSpecialization = true; 5009 } 5010 } 5011 } 5012 5013 DeclContext *SearchDC = CurContext; 5014 DeclContext *DC = CurContext; 5015 bool isStdBadAlloc = false; 5016 bool Invalid = false; 5017 5018 RedeclarationKind Redecl = ForRedeclaration; 5019 if (TUK == TUK_Friend || TUK == TUK_Reference) 5020 Redecl = NotForRedeclaration; 5021 5022 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5023 5024 if (Name && SS.isNotEmpty()) { 5025 // We have a nested-name tag ('struct foo::bar'). 5026 5027 // Check for invalid 'foo::'. 5028 if (SS.isInvalid()) { 5029 Name = 0; 5030 goto CreateNewDecl; 5031 } 5032 5033 // If this is a friend or a reference to a class in a dependent 5034 // context, don't try to make a decl for it. 5035 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5036 DC = computeDeclContext(SS, false); 5037 if (!DC) { 5038 IsDependent = true; 5039 return DeclPtrTy(); 5040 } 5041 } else { 5042 DC = computeDeclContext(SS, true); 5043 if (!DC) { 5044 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5045 << SS.getRange(); 5046 return DeclPtrTy(); 5047 } 5048 } 5049 5050 if (RequireCompleteDeclContext(SS, DC)) 5051 return DeclPtrTy::make((Decl *)0); 5052 5053 SearchDC = DC; 5054 // Look-up name inside 'foo::'. 5055 LookupQualifiedName(Previous, DC); 5056 5057 if (Previous.isAmbiguous()) 5058 return DeclPtrTy(); 5059 5060 if (Previous.empty()) { 5061 // Name lookup did not find anything. However, if the 5062 // nested-name-specifier refers to the current instantiation, 5063 // and that current instantiation has any dependent base 5064 // classes, we might find something at instantiation time: treat 5065 // this as a dependent elaborated-type-specifier. 5066 if (Previous.wasNotFoundInCurrentInstantiation()) { 5067 IsDependent = true; 5068 return DeclPtrTy(); 5069 } 5070 5071 // A tag 'foo::bar' must already exist. 5072 Diag(NameLoc, diag::err_not_tag_in_scope) 5073 << Kind << Name << DC << SS.getRange(); 5074 Name = 0; 5075 Invalid = true; 5076 goto CreateNewDecl; 5077 } 5078 } else if (Name) { 5079 // If this is a named struct, check to see if there was a previous forward 5080 // declaration or definition. 5081 // FIXME: We're looking into outer scopes here, even when we 5082 // shouldn't be. Doing so can result in ambiguities that we 5083 // shouldn't be diagnosing. 5084 LookupName(Previous, S); 5085 5086 // Note: there used to be some attempt at recovery here. 5087 if (Previous.isAmbiguous()) 5088 return DeclPtrTy(); 5089 5090 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5091 // FIXME: This makes sure that we ignore the contexts associated 5092 // with C structs, unions, and enums when looking for a matching 5093 // tag declaration or definition. See the similar lookup tweak 5094 // in Sema::LookupName; is there a better way to deal with this? 5095 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5096 SearchDC = SearchDC->getParent(); 5097 } 5098 } 5099 5100 if (Previous.isSingleResult() && 5101 Previous.getFoundDecl()->isTemplateParameter()) { 5102 // Maybe we will complain about the shadowed template parameter. 5103 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5104 // Just pretend that we didn't see the previous declaration. 5105 Previous.clear(); 5106 } 5107 5108 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5109 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 5110 // This is a declaration of or a reference to "std::bad_alloc". 5111 isStdBadAlloc = true; 5112 5113 if (Previous.empty() && StdBadAlloc) { 5114 // std::bad_alloc has been implicitly declared (but made invisible to 5115 // name lookup). Fill in this implicit declaration as the previous 5116 // declaration, so that the declarations get chained appropriately. 5117 Previous.addDecl(StdBadAlloc); 5118 } 5119 } 5120 5121 // If we didn't find a previous declaration, and this is a reference 5122 // (or friend reference), move to the correct scope. In C++, we 5123 // also need to do a redeclaration lookup there, just in case 5124 // there's a shadow friend decl. 5125 if (Name && Previous.empty() && 5126 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5127 if (Invalid) goto CreateNewDecl; 5128 assert(SS.isEmpty()); 5129 5130 if (TUK == TUK_Reference) { 5131 // C++ [basic.scope.pdecl]p5: 5132 // -- for an elaborated-type-specifier of the form 5133 // 5134 // class-key identifier 5135 // 5136 // if the elaborated-type-specifier is used in the 5137 // decl-specifier-seq or parameter-declaration-clause of a 5138 // function defined in namespace scope, the identifier is 5139 // declared as a class-name in the namespace that contains 5140 // the declaration; otherwise, except as a friend 5141 // declaration, the identifier is declared in the smallest 5142 // non-class, non-function-prototype scope that contains the 5143 // declaration. 5144 // 5145 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5146 // C structs and unions. 5147 // 5148 // It is an error in C++ to declare (rather than define) an enum 5149 // type, including via an elaborated type specifier. We'll 5150 // diagnose that later; for now, declare the enum in the same 5151 // scope as we would have picked for any other tag type. 5152 // 5153 // GNU C also supports this behavior as part of its incomplete 5154 // enum types extension, while GNU C++ does not. 5155 // 5156 // Find the context where we'll be declaring the tag. 5157 // FIXME: We would like to maintain the current DeclContext as the 5158 // lexical context, 5159 while (SearchDC->isRecord()) 5160 SearchDC = SearchDC->getParent(); 5161 5162 // Find the scope where we'll be declaring the tag. 5163 while (S->isClassScope() || 5164 (getLangOptions().CPlusPlus && 5165 S->isFunctionPrototypeScope()) || 5166 ((S->getFlags() & Scope::DeclScope) == 0) || 5167 (S->getEntity() && 5168 ((DeclContext *)S->getEntity())->isTransparentContext())) 5169 S = S->getParent(); 5170 } else { 5171 assert(TUK == TUK_Friend); 5172 // C++ [namespace.memdef]p3: 5173 // If a friend declaration in a non-local class first declares a 5174 // class or function, the friend class or function is a member of 5175 // the innermost enclosing namespace. 5176 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5177 } 5178 5179 // In C++, we need to do a redeclaration lookup to properly 5180 // diagnose some problems. 5181 if (getLangOptions().CPlusPlus) { 5182 Previous.setRedeclarationKind(ForRedeclaration); 5183 LookupQualifiedName(Previous, SearchDC); 5184 } 5185 } 5186 5187 if (!Previous.empty()) { 5188 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5189 5190 // It's okay to have a tag decl in the same scope as a typedef 5191 // which hides a tag decl in the same scope. Finding this 5192 // insanity with a redeclaration lookup can only actually happen 5193 // in C++. 5194 // 5195 // This is also okay for elaborated-type-specifiers, which is 5196 // technically forbidden by the current standard but which is 5197 // okay according to the likely resolution of an open issue; 5198 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5199 if (getLangOptions().CPlusPlus) { 5200 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5201 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5202 TagDecl *Tag = TT->getDecl(); 5203 if (Tag->getDeclName() == Name && 5204 Tag->getDeclContext()->getLookupContext() 5205 ->Equals(TD->getDeclContext()->getLookupContext())) { 5206 PrevDecl = Tag; 5207 Previous.clear(); 5208 Previous.addDecl(Tag); 5209 } 5210 } 5211 } 5212 } 5213 5214 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5215 // If this is a use of a previous tag, or if the tag is already declared 5216 // in the same scope (so that the definition/declaration completes or 5217 // rementions the tag), reuse the decl. 5218 if (TUK == TUK_Reference || TUK == TUK_Friend || 5219 isDeclInScope(PrevDecl, SearchDC, S)) { 5220 // Make sure that this wasn't declared as an enum and now used as a 5221 // struct or something similar. 5222 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5223 bool SafeToContinue 5224 = (PrevTagDecl->getTagKind() != TTK_Enum && 5225 Kind != TTK_Enum); 5226 if (SafeToContinue) 5227 Diag(KWLoc, diag::err_use_with_wrong_tag) 5228 << Name 5229 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5230 PrevTagDecl->getKindName()); 5231 else 5232 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5233 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5234 5235 if (SafeToContinue) 5236 Kind = PrevTagDecl->getTagKind(); 5237 else { 5238 // Recover by making this an anonymous redefinition. 5239 Name = 0; 5240 Previous.clear(); 5241 Invalid = true; 5242 } 5243 } 5244 5245 if (!Invalid) { 5246 // If this is a use, just return the declaration we found. 5247 5248 // FIXME: In the future, return a variant or some other clue 5249 // for the consumer of this Decl to know it doesn't own it. 5250 // For our current ASTs this shouldn't be a problem, but will 5251 // need to be changed with DeclGroups. 5252 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5253 TUK == TUK_Friend) 5254 return DeclPtrTy::make(PrevTagDecl); 5255 5256 // Diagnose attempts to redefine a tag. 5257 if (TUK == TUK_Definition) { 5258 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5259 // If we're defining a specialization and the previous definition 5260 // is from an implicit instantiation, don't emit an error 5261 // here; we'll catch this in the general case below. 5262 if (!isExplicitSpecialization || 5263 !isa<CXXRecordDecl>(Def) || 5264 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5265 == TSK_ExplicitSpecialization) { 5266 Diag(NameLoc, diag::err_redefinition) << Name; 5267 Diag(Def->getLocation(), diag::note_previous_definition); 5268 // If this is a redefinition, recover by making this 5269 // struct be anonymous, which will make any later 5270 // references get the previous definition. 5271 Name = 0; 5272 Previous.clear(); 5273 Invalid = true; 5274 } 5275 } else { 5276 // If the type is currently being defined, complain 5277 // about a nested redefinition. 5278 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5279 if (Tag->isBeingDefined()) { 5280 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5281 Diag(PrevTagDecl->getLocation(), 5282 diag::note_previous_definition); 5283 Name = 0; 5284 Previous.clear(); 5285 Invalid = true; 5286 } 5287 } 5288 5289 // Okay, this is definition of a previously declared or referenced 5290 // tag PrevDecl. We're going to create a new Decl for it. 5291 } 5292 } 5293 // If we get here we have (another) forward declaration or we 5294 // have a definition. Just create a new decl. 5295 5296 } else { 5297 // If we get here, this is a definition of a new tag type in a nested 5298 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5299 // new decl/type. We set PrevDecl to NULL so that the entities 5300 // have distinct types. 5301 Previous.clear(); 5302 } 5303 // If we get here, we're going to create a new Decl. If PrevDecl 5304 // is non-NULL, it's a definition of the tag declared by 5305 // PrevDecl. If it's NULL, we have a new definition. 5306 5307 5308 // Otherwise, PrevDecl is not a tag, but was found with tag 5309 // lookup. This is only actually possible in C++, where a few 5310 // things like templates still live in the tag namespace. 5311 } else { 5312 assert(getLangOptions().CPlusPlus); 5313 5314 // Use a better diagnostic if an elaborated-type-specifier 5315 // found the wrong kind of type on the first 5316 // (non-redeclaration) lookup. 5317 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5318 !Previous.isForRedeclaration()) { 5319 unsigned Kind = 0; 5320 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5321 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5322 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5323 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5324 Invalid = true; 5325 5326 // Otherwise, only diagnose if the declaration is in scope. 5327 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5328 // do nothing 5329 5330 // Diagnose implicit declarations introduced by elaborated types. 5331 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5332 unsigned Kind = 0; 5333 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5334 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5335 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5336 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5337 Invalid = true; 5338 5339 // Otherwise it's a declaration. Call out a particularly common 5340 // case here. 5341 } else if (isa<TypedefDecl>(PrevDecl)) { 5342 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5343 << Name 5344 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5345 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5346 Invalid = true; 5347 5348 // Otherwise, diagnose. 5349 } else { 5350 // The tag name clashes with something else in the target scope, 5351 // issue an error and recover by making this tag be anonymous. 5352 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5353 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5354 Name = 0; 5355 Invalid = true; 5356 } 5357 5358 // The existing declaration isn't relevant to us; we're in a 5359 // new scope, so clear out the previous declaration. 5360 Previous.clear(); 5361 } 5362 } 5363 5364CreateNewDecl: 5365 5366 TagDecl *PrevDecl = 0; 5367 if (Previous.isSingleResult()) 5368 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5369 5370 // If there is an identifier, use the location of the identifier as the 5371 // location of the decl, otherwise use the location of the struct/union 5372 // keyword. 5373 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5374 5375 // Otherwise, create a new declaration. If there is a previous 5376 // declaration of the same entity, the two will be linked via 5377 // PrevDecl. 5378 TagDecl *New; 5379 5380 if (Kind == TTK_Enum) { 5381 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5382 // enum X { A, B, C } D; D should chain to X. 5383 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5384 cast_or_null<EnumDecl>(PrevDecl)); 5385 // If this is an undefined enum, warn. 5386 if (TUK != TUK_Definition && !Invalid) { 5387 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5388 : diag::ext_forward_ref_enum; 5389 Diag(Loc, DK); 5390 } 5391 } else { 5392 // struct/union/class 5393 5394 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5395 // struct X { int A; } D; D should chain to X. 5396 if (getLangOptions().CPlusPlus) { 5397 // FIXME: Look for a way to use RecordDecl for simple structs. 5398 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5399 cast_or_null<CXXRecordDecl>(PrevDecl)); 5400 5401 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5402 StdBadAlloc = cast<CXXRecordDecl>(New); 5403 } else 5404 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5405 cast_or_null<RecordDecl>(PrevDecl)); 5406 } 5407 5408 // Maybe add qualifier info. 5409 if (SS.isNotEmpty()) { 5410 if (SS.isSet()) { 5411 NestedNameSpecifier *NNS 5412 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5413 New->setQualifierInfo(NNS, SS.getRange()); 5414 if (NumMatchedTemplateParamLists > 0) { 5415 New->setTemplateParameterListsInfo(NumMatchedTemplateParamLists, 5416 (TemplateParameterList**) TemplateParameterLists.release()); 5417 } 5418 } 5419 else 5420 Invalid = true; 5421 } 5422 5423 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5424 // Add alignment attributes if necessary; these attributes are checked when 5425 // the ASTContext lays out the structure. 5426 // 5427 // It is important for implementing the correct semantics that this 5428 // happen here (in act on tag decl). The #pragma pack stack is 5429 // maintained as a result of parser callbacks which can occur at 5430 // many points during the parsing of a struct declaration (because 5431 // the #pragma tokens are effectively skipped over during the 5432 // parsing of the struct). 5433 AddAlignmentAttributesForRecord(RD); 5434 } 5435 5436 // If this is a specialization of a member class (of a class template), 5437 // check the specialization. 5438 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5439 Invalid = true; 5440 5441 if (Invalid) 5442 New->setInvalidDecl(); 5443 5444 if (Attr) 5445 ProcessDeclAttributeList(S, New, Attr); 5446 5447 // If we're declaring or defining a tag in function prototype scope 5448 // in C, note that this type can only be used within the function. 5449 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5450 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5451 5452 // Set the lexical context. If the tag has a C++ scope specifier, the 5453 // lexical context will be different from the semantic context. 5454 New->setLexicalDeclContext(CurContext); 5455 5456 // Mark this as a friend decl if applicable. 5457 if (TUK == TUK_Friend) 5458 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5459 5460 // Set the access specifier. 5461 if (!Invalid && SearchDC->isRecord()) 5462 SetMemberAccessSpecifier(New, PrevDecl, AS); 5463 5464 if (TUK == TUK_Definition) 5465 New->startDefinition(); 5466 5467 // If this has an identifier, add it to the scope stack. 5468 if (TUK == TUK_Friend) { 5469 // We might be replacing an existing declaration in the lookup tables; 5470 // if so, borrow its access specifier. 5471 if (PrevDecl) 5472 New->setAccess(PrevDecl->getAccess()); 5473 5474 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5475 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5476 if (Name) // can be null along some error paths 5477 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5478 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5479 } else if (Name) { 5480 S = getNonFieldDeclScope(S); 5481 PushOnScopeChains(New, S); 5482 } else { 5483 CurContext->addDecl(New); 5484 } 5485 5486 // If this is the C FILE type, notify the AST context. 5487 if (IdentifierInfo *II = New->getIdentifier()) 5488 if (!New->isInvalidDecl() && 5489 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5490 II->isStr("FILE")) 5491 Context.setFILEDecl(New); 5492 5493 OwnedDecl = true; 5494 return DeclPtrTy::make(New); 5495} 5496 5497void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5498 AdjustDeclIfTemplate(TagD); 5499 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5500 5501 // Enter the tag context. 5502 PushDeclContext(S, Tag); 5503} 5504 5505void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5506 SourceLocation LBraceLoc) { 5507 AdjustDeclIfTemplate(TagD); 5508 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5509 5510 FieldCollector->StartClass(); 5511 5512 if (!Record->getIdentifier()) 5513 return; 5514 5515 // C++ [class]p2: 5516 // [...] The class-name is also inserted into the scope of the 5517 // class itself; this is known as the injected-class-name. For 5518 // purposes of access checking, the injected-class-name is treated 5519 // as if it were a public member name. 5520 CXXRecordDecl *InjectedClassName 5521 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5522 CurContext, Record->getLocation(), 5523 Record->getIdentifier(), 5524 Record->getTagKeywordLoc(), 5525 Record); 5526 InjectedClassName->setImplicit(); 5527 InjectedClassName->setAccess(AS_public); 5528 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5529 InjectedClassName->setDescribedClassTemplate(Template); 5530 PushOnScopeChains(InjectedClassName, S); 5531 assert(InjectedClassName->isInjectedClassName() && 5532 "Broken injected-class-name"); 5533} 5534 5535void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5536 SourceLocation RBraceLoc) { 5537 AdjustDeclIfTemplate(TagD); 5538 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5539 Tag->setRBraceLoc(RBraceLoc); 5540 5541 if (isa<CXXRecordDecl>(Tag)) 5542 FieldCollector->FinishClass(); 5543 5544 // Exit this scope of this tag's definition. 5545 PopDeclContext(); 5546 5547 // Notify the consumer that we've defined a tag. 5548 Consumer.HandleTagDeclDefinition(Tag); 5549} 5550 5551void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5552 AdjustDeclIfTemplate(TagD); 5553 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5554 Tag->setInvalidDecl(); 5555 5556 // We're undoing ActOnTagStartDefinition here, not 5557 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5558 // the FieldCollector. 5559 5560 PopDeclContext(); 5561} 5562 5563// Note that FieldName may be null for anonymous bitfields. 5564bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5565 QualType FieldTy, const Expr *BitWidth, 5566 bool *ZeroWidth) { 5567 // Default to true; that shouldn't confuse checks for emptiness 5568 if (ZeroWidth) 5569 *ZeroWidth = true; 5570 5571 // C99 6.7.2.1p4 - verify the field type. 5572 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5573 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5574 // Handle incomplete types with specific error. 5575 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5576 return true; 5577 if (FieldName) 5578 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5579 << FieldName << FieldTy << BitWidth->getSourceRange(); 5580 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5581 << FieldTy << BitWidth->getSourceRange(); 5582 } 5583 5584 // If the bit-width is type- or value-dependent, don't try to check 5585 // it now. 5586 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5587 return false; 5588 5589 llvm::APSInt Value; 5590 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5591 return true; 5592 5593 if (Value != 0 && ZeroWidth) 5594 *ZeroWidth = false; 5595 5596 // Zero-width bitfield is ok for anonymous field. 5597 if (Value == 0 && FieldName) 5598 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5599 5600 if (Value.isSigned() && Value.isNegative()) { 5601 if (FieldName) 5602 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5603 << FieldName << Value.toString(10); 5604 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5605 << Value.toString(10); 5606 } 5607 5608 if (!FieldTy->isDependentType()) { 5609 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5610 if (Value.getZExtValue() > TypeSize) { 5611 if (!getLangOptions().CPlusPlus) { 5612 if (FieldName) 5613 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5614 << FieldName << (unsigned)Value.getZExtValue() 5615 << (unsigned)TypeSize; 5616 5617 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5618 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5619 } 5620 5621 if (FieldName) 5622 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5623 << FieldName << (unsigned)Value.getZExtValue() 5624 << (unsigned)TypeSize; 5625 else 5626 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5627 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5628 } 5629 } 5630 5631 return false; 5632} 5633 5634/// ActOnField - Each field of a struct/union/class is passed into this in order 5635/// to create a FieldDecl object for it. 5636Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5637 SourceLocation DeclStart, 5638 Declarator &D, ExprTy *BitfieldWidth) { 5639 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5640 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5641 AS_public); 5642 return DeclPtrTy::make(Res); 5643} 5644 5645/// HandleField - Analyze a field of a C struct or a C++ data member. 5646/// 5647FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5648 SourceLocation DeclStart, 5649 Declarator &D, Expr *BitWidth, 5650 AccessSpecifier AS) { 5651 IdentifierInfo *II = D.getIdentifier(); 5652 SourceLocation Loc = DeclStart; 5653 if (II) Loc = D.getIdentifierLoc(); 5654 5655 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5656 QualType T = TInfo->getType(); 5657 if (getLangOptions().CPlusPlus) 5658 CheckExtraCXXDefaultArguments(D); 5659 5660 DiagnoseFunctionSpecifiers(D); 5661 5662 if (D.getDeclSpec().isThreadSpecified()) 5663 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5664 5665 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5666 ForRedeclaration); 5667 5668 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5669 // Maybe we will complain about the shadowed template parameter. 5670 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5671 // Just pretend that we didn't see the previous declaration. 5672 PrevDecl = 0; 5673 } 5674 5675 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5676 PrevDecl = 0; 5677 5678 bool Mutable 5679 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5680 SourceLocation TSSL = D.getSourceRange().getBegin(); 5681 FieldDecl *NewFD 5682 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5683 AS, PrevDecl, &D); 5684 5685 if (NewFD->isInvalidDecl()) 5686 Record->setInvalidDecl(); 5687 5688 if (NewFD->isInvalidDecl() && PrevDecl) { 5689 // Don't introduce NewFD into scope; there's already something 5690 // with the same name in the same scope. 5691 } else if (II) { 5692 PushOnScopeChains(NewFD, S); 5693 } else 5694 Record->addDecl(NewFD); 5695 5696 return NewFD; 5697} 5698 5699/// \brief Build a new FieldDecl and check its well-formedness. 5700/// 5701/// This routine builds a new FieldDecl given the fields name, type, 5702/// record, etc. \p PrevDecl should refer to any previous declaration 5703/// with the same name and in the same scope as the field to be 5704/// created. 5705/// 5706/// \returns a new FieldDecl. 5707/// 5708/// \todo The Declarator argument is a hack. It will be removed once 5709FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5710 TypeSourceInfo *TInfo, 5711 RecordDecl *Record, SourceLocation Loc, 5712 bool Mutable, Expr *BitWidth, 5713 SourceLocation TSSL, 5714 AccessSpecifier AS, NamedDecl *PrevDecl, 5715 Declarator *D) { 5716 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5717 bool InvalidDecl = false; 5718 if (D) InvalidDecl = D->isInvalidType(); 5719 5720 // If we receive a broken type, recover by assuming 'int' and 5721 // marking this declaration as invalid. 5722 if (T.isNull()) { 5723 InvalidDecl = true; 5724 T = Context.IntTy; 5725 } 5726 5727 QualType EltTy = Context.getBaseElementType(T); 5728 if (!EltTy->isDependentType() && 5729 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5730 InvalidDecl = true; 5731 5732 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5733 // than a variably modified type. 5734 if (!InvalidDecl && T->isVariablyModifiedType()) { 5735 bool SizeIsNegative; 5736 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5737 SizeIsNegative); 5738 if (!FixedTy.isNull()) { 5739 Diag(Loc, diag::warn_illegal_constant_array_size); 5740 T = FixedTy; 5741 } else { 5742 if (SizeIsNegative) 5743 Diag(Loc, diag::err_typecheck_negative_array_size); 5744 else 5745 Diag(Loc, diag::err_typecheck_field_variable_size); 5746 InvalidDecl = true; 5747 } 5748 } 5749 5750 // Fields can not have abstract class types 5751 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5752 diag::err_abstract_type_in_decl, 5753 AbstractFieldType)) 5754 InvalidDecl = true; 5755 5756 bool ZeroWidth = false; 5757 // If this is declared as a bit-field, check the bit-field. 5758 if (!InvalidDecl && BitWidth && 5759 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5760 InvalidDecl = true; 5761 DeleteExpr(BitWidth); 5762 BitWidth = 0; 5763 ZeroWidth = false; 5764 } 5765 5766 // Check that 'mutable' is consistent with the type of the declaration. 5767 if (!InvalidDecl && Mutable) { 5768 unsigned DiagID = 0; 5769 if (T->isReferenceType()) 5770 DiagID = diag::err_mutable_reference; 5771 else if (T.isConstQualified()) 5772 DiagID = diag::err_mutable_const; 5773 5774 if (DiagID) { 5775 SourceLocation ErrLoc = Loc; 5776 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 5777 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 5778 Diag(ErrLoc, DiagID); 5779 Mutable = false; 5780 InvalidDecl = true; 5781 } 5782 } 5783 5784 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5785 BitWidth, Mutable); 5786 if (InvalidDecl) 5787 NewFD->setInvalidDecl(); 5788 5789 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5790 Diag(Loc, diag::err_duplicate_member) << II; 5791 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5792 NewFD->setInvalidDecl(); 5793 } 5794 5795 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5796 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5797 5798 if (!T->isPODType()) 5799 CXXRecord->setPOD(false); 5800 if (!ZeroWidth) 5801 CXXRecord->setEmpty(false); 5802 5803 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5804 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5805 5806 if (!RDecl->hasTrivialConstructor()) 5807 CXXRecord->setHasTrivialConstructor(false); 5808 if (!RDecl->hasTrivialCopyConstructor()) 5809 CXXRecord->setHasTrivialCopyConstructor(false); 5810 if (!RDecl->hasTrivialCopyAssignment()) 5811 CXXRecord->setHasTrivialCopyAssignment(false); 5812 if (!RDecl->hasTrivialDestructor()) 5813 CXXRecord->setHasTrivialDestructor(false); 5814 5815 // C++ 9.5p1: An object of a class with a non-trivial 5816 // constructor, a non-trivial copy constructor, a non-trivial 5817 // destructor, or a non-trivial copy assignment operator 5818 // cannot be a member of a union, nor can an array of such 5819 // objects. 5820 // TODO: C++0x alters this restriction significantly. 5821 if (Record->isUnion()) { 5822 // We check for copy constructors before constructors 5823 // because otherwise we'll never get complaints about 5824 // copy constructors. 5825 5826 CXXSpecialMember member = CXXInvalid; 5827 if (!RDecl->hasTrivialCopyConstructor()) 5828 member = CXXCopyConstructor; 5829 else if (!RDecl->hasTrivialConstructor()) 5830 member = CXXConstructor; 5831 else if (!RDecl->hasTrivialCopyAssignment()) 5832 member = CXXCopyAssignment; 5833 else if (!RDecl->hasTrivialDestructor()) 5834 member = CXXDestructor; 5835 5836 if (member != CXXInvalid) { 5837 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5838 DiagnoseNontrivial(RT, member); 5839 NewFD->setInvalidDecl(); 5840 } 5841 } 5842 } 5843 } 5844 5845 // FIXME: We need to pass in the attributes given an AST 5846 // representation, not a parser representation. 5847 if (D) 5848 // FIXME: What to pass instead of TUScope? 5849 ProcessDeclAttributes(TUScope, NewFD, *D); 5850 5851 if (T.isObjCGCWeak()) 5852 Diag(Loc, diag::warn_attribute_weak_on_field); 5853 5854 NewFD->setAccess(AS); 5855 5856 // C++ [dcl.init.aggr]p1: 5857 // An aggregate is an array or a class (clause 9) with [...] no 5858 // private or protected non-static data members (clause 11). 5859 // A POD must be an aggregate. 5860 if (getLangOptions().CPlusPlus && 5861 (AS == AS_private || AS == AS_protected)) { 5862 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5863 CXXRecord->setAggregate(false); 5864 CXXRecord->setPOD(false); 5865 } 5866 5867 return NewFD; 5868} 5869 5870/// DiagnoseNontrivial - Given that a class has a non-trivial 5871/// special member, figure out why. 5872void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5873 QualType QT(T, 0U); 5874 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5875 5876 // Check whether the member was user-declared. 5877 switch (member) { 5878 case CXXInvalid: 5879 break; 5880 5881 case CXXConstructor: 5882 if (RD->hasUserDeclaredConstructor()) { 5883 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5884 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5885 const FunctionDecl *body = 0; 5886 ci->getBody(body); 5887 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5888 SourceLocation CtorLoc = ci->getLocation(); 5889 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5890 return; 5891 } 5892 } 5893 5894 assert(0 && "found no user-declared constructors"); 5895 return; 5896 } 5897 break; 5898 5899 case CXXCopyConstructor: 5900 if (RD->hasUserDeclaredCopyConstructor()) { 5901 SourceLocation CtorLoc = 5902 RD->getCopyConstructor(Context, 0)->getLocation(); 5903 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5904 return; 5905 } 5906 break; 5907 5908 case CXXCopyAssignment: 5909 if (RD->hasUserDeclaredCopyAssignment()) { 5910 // FIXME: this should use the location of the copy 5911 // assignment, not the type. 5912 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5913 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5914 return; 5915 } 5916 break; 5917 5918 case CXXDestructor: 5919 if (RD->hasUserDeclaredDestructor()) { 5920 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5921 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5922 return; 5923 } 5924 break; 5925 } 5926 5927 typedef CXXRecordDecl::base_class_iterator base_iter; 5928 5929 // Virtual bases and members inhibit trivial copying/construction, 5930 // but not trivial destruction. 5931 if (member != CXXDestructor) { 5932 // Check for virtual bases. vbases includes indirect virtual bases, 5933 // so we just iterate through the direct bases. 5934 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5935 if (bi->isVirtual()) { 5936 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5937 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5938 return; 5939 } 5940 5941 // Check for virtual methods. 5942 typedef CXXRecordDecl::method_iterator meth_iter; 5943 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5944 ++mi) { 5945 if (mi->isVirtual()) { 5946 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5947 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5948 return; 5949 } 5950 } 5951 } 5952 5953 bool (CXXRecordDecl::*hasTrivial)() const; 5954 switch (member) { 5955 case CXXConstructor: 5956 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5957 case CXXCopyConstructor: 5958 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5959 case CXXCopyAssignment: 5960 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5961 case CXXDestructor: 5962 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5963 default: 5964 assert(0 && "unexpected special member"); return; 5965 } 5966 5967 // Check for nontrivial bases (and recurse). 5968 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5969 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5970 assert(BaseRT && "Don't know how to handle dependent bases"); 5971 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5972 if (!(BaseRecTy->*hasTrivial)()) { 5973 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5974 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5975 DiagnoseNontrivial(BaseRT, member); 5976 return; 5977 } 5978 } 5979 5980 // Check for nontrivial members (and recurse). 5981 typedef RecordDecl::field_iterator field_iter; 5982 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5983 ++fi) { 5984 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5985 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5986 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5987 5988 if (!(EltRD->*hasTrivial)()) { 5989 SourceLocation FLoc = (*fi)->getLocation(); 5990 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5991 DiagnoseNontrivial(EltRT, member); 5992 return; 5993 } 5994 } 5995 } 5996 5997 assert(0 && "found no explanation for non-trivial member"); 5998} 5999 6000/// TranslateIvarVisibility - Translate visibility from a token ID to an 6001/// AST enum value. 6002static ObjCIvarDecl::AccessControl 6003TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6004 switch (ivarVisibility) { 6005 default: assert(0 && "Unknown visitibility kind"); 6006 case tok::objc_private: return ObjCIvarDecl::Private; 6007 case tok::objc_public: return ObjCIvarDecl::Public; 6008 case tok::objc_protected: return ObjCIvarDecl::Protected; 6009 case tok::objc_package: return ObjCIvarDecl::Package; 6010 } 6011} 6012 6013/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6014/// in order to create an IvarDecl object for it. 6015Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 6016 SourceLocation DeclStart, 6017 DeclPtrTy IntfDecl, 6018 Declarator &D, ExprTy *BitfieldWidth, 6019 tok::ObjCKeywordKind Visibility) { 6020 6021 IdentifierInfo *II = D.getIdentifier(); 6022 Expr *BitWidth = (Expr*)BitfieldWidth; 6023 SourceLocation Loc = DeclStart; 6024 if (II) Loc = D.getIdentifierLoc(); 6025 6026 // FIXME: Unnamed fields can be handled in various different ways, for 6027 // example, unnamed unions inject all members into the struct namespace! 6028 6029 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6030 QualType T = TInfo->getType(); 6031 6032 if (BitWidth) { 6033 // 6.7.2.1p3, 6.7.2.1p4 6034 if (VerifyBitField(Loc, II, T, BitWidth)) { 6035 D.setInvalidType(); 6036 DeleteExpr(BitWidth); 6037 BitWidth = 0; 6038 } 6039 } else { 6040 // Not a bitfield. 6041 6042 // validate II. 6043 6044 } 6045 if (T->isReferenceType()) { 6046 Diag(Loc, diag::err_ivar_reference_type); 6047 D.setInvalidType(); 6048 } 6049 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6050 // than a variably modified type. 6051 else if (T->isVariablyModifiedType()) { 6052 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6053 D.setInvalidType(); 6054 } 6055 6056 // Get the visibility (access control) for this ivar. 6057 ObjCIvarDecl::AccessControl ac = 6058 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6059 : ObjCIvarDecl::None; 6060 // Must set ivar's DeclContext to its enclosing interface. 6061 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 6062 ObjCContainerDecl *EnclosingContext; 6063 if (ObjCImplementationDecl *IMPDecl = 6064 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6065 // Case of ivar declared in an implementation. Context is that of its class. 6066 EnclosingContext = IMPDecl->getClassInterface(); 6067 assert(EnclosingContext && "Implementation has no class interface!"); 6068 } else { 6069 if (ObjCCategoryDecl *CDecl = 6070 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6071 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6072 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6073 return DeclPtrTy(); 6074 } 6075 } 6076 EnclosingContext = EnclosingDecl; 6077 } 6078 6079 // Construct the decl. 6080 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6081 EnclosingContext, Loc, II, T, 6082 TInfo, ac, (Expr *)BitfieldWidth); 6083 6084 if (II) { 6085 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6086 ForRedeclaration); 6087 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6088 && !isa<TagDecl>(PrevDecl)) { 6089 Diag(Loc, diag::err_duplicate_member) << II; 6090 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6091 NewID->setInvalidDecl(); 6092 } 6093 } 6094 6095 // Process attributes attached to the ivar. 6096 ProcessDeclAttributes(S, NewID, D); 6097 6098 if (D.isInvalidType()) 6099 NewID->setInvalidDecl(); 6100 6101 if (II) { 6102 // FIXME: When interfaces are DeclContexts, we'll need to add 6103 // these to the interface. 6104 S->AddDecl(DeclPtrTy::make(NewID)); 6105 IdResolver.AddDecl(NewID); 6106 } 6107 6108 return DeclPtrTy::make(NewID); 6109} 6110 6111void Sema::ActOnFields(Scope* S, 6112 SourceLocation RecLoc, DeclPtrTy RecDecl, 6113 DeclPtrTy *Fields, unsigned NumFields, 6114 SourceLocation LBrac, SourceLocation RBrac, 6115 AttributeList *Attr) { 6116 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 6117 assert(EnclosingDecl && "missing record or interface decl"); 6118 6119 // If the decl this is being inserted into is invalid, then it may be a 6120 // redeclaration or some other bogus case. Don't try to add fields to it. 6121 if (EnclosingDecl->isInvalidDecl()) { 6122 // FIXME: Deallocate fields? 6123 return; 6124 } 6125 6126 6127 // Verify that all the fields are okay. 6128 unsigned NumNamedMembers = 0; 6129 llvm::SmallVector<FieldDecl*, 32> RecFields; 6130 6131 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6132 for (unsigned i = 0; i != NumFields; ++i) { 6133 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 6134 6135 // Get the type for the field. 6136 Type *FDTy = FD->getType().getTypePtr(); 6137 6138 if (!FD->isAnonymousStructOrUnion()) { 6139 // Remember all fields written by the user. 6140 RecFields.push_back(FD); 6141 } 6142 6143 // If the field is already invalid for some reason, don't emit more 6144 // diagnostics about it. 6145 if (FD->isInvalidDecl()) { 6146 EnclosingDecl->setInvalidDecl(); 6147 continue; 6148 } 6149 6150 // C99 6.7.2.1p2: 6151 // A structure or union shall not contain a member with 6152 // incomplete or function type (hence, a structure shall not 6153 // contain an instance of itself, but may contain a pointer to 6154 // an instance of itself), except that the last member of a 6155 // structure with more than one named member may have incomplete 6156 // array type; such a structure (and any union containing, 6157 // possibly recursively, a member that is such a structure) 6158 // shall not be a member of a structure or an element of an 6159 // array. 6160 if (FDTy->isFunctionType()) { 6161 // Field declared as a function. 6162 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6163 << FD->getDeclName(); 6164 FD->setInvalidDecl(); 6165 EnclosingDecl->setInvalidDecl(); 6166 continue; 6167 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6168 Record && Record->isStruct()) { 6169 // Flexible array member. 6170 if (NumNamedMembers < 1) { 6171 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6172 << FD->getDeclName(); 6173 FD->setInvalidDecl(); 6174 EnclosingDecl->setInvalidDecl(); 6175 continue; 6176 } 6177 if (!FD->getType()->isDependentType() && 6178 !Context.getBaseElementType(FD->getType())->isPODType()) { 6179 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6180 << FD->getDeclName() << FD->getType(); 6181 FD->setInvalidDecl(); 6182 EnclosingDecl->setInvalidDecl(); 6183 continue; 6184 } 6185 6186 // Okay, we have a legal flexible array member at the end of the struct. 6187 if (Record) 6188 Record->setHasFlexibleArrayMember(true); 6189 } else if (!FDTy->isDependentType() && 6190 RequireCompleteType(FD->getLocation(), FD->getType(), 6191 diag::err_field_incomplete)) { 6192 // Incomplete type 6193 FD->setInvalidDecl(); 6194 EnclosingDecl->setInvalidDecl(); 6195 continue; 6196 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6197 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6198 // If this is a member of a union, then entire union becomes "flexible". 6199 if (Record && Record->isUnion()) { 6200 Record->setHasFlexibleArrayMember(true); 6201 } else { 6202 // If this is a struct/class and this is not the last element, reject 6203 // it. Note that GCC supports variable sized arrays in the middle of 6204 // structures. 6205 if (i != NumFields-1) 6206 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6207 << FD->getDeclName() << FD->getType(); 6208 else { 6209 // We support flexible arrays at the end of structs in 6210 // other structs as an extension. 6211 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6212 << FD->getDeclName(); 6213 if (Record) 6214 Record->setHasFlexibleArrayMember(true); 6215 } 6216 } 6217 } 6218 if (Record && FDTTy->getDecl()->hasObjectMember()) 6219 Record->setHasObjectMember(true); 6220 } else if (FDTy->isObjCObjectType()) { 6221 /// A field cannot be an Objective-c object 6222 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6223 FD->setInvalidDecl(); 6224 EnclosingDecl->setInvalidDecl(); 6225 continue; 6226 } else if (getLangOptions().ObjC1 && 6227 getLangOptions().getGCMode() != LangOptions::NonGC && 6228 Record && 6229 (FD->getType()->isObjCObjectPointerType() || 6230 FD->getType().isObjCGCStrong())) 6231 Record->setHasObjectMember(true); 6232 // Keep track of the number of named members. 6233 if (FD->getIdentifier()) 6234 ++NumNamedMembers; 6235 } 6236 6237 // Okay, we successfully defined 'Record'. 6238 if (Record) { 6239 Record->completeDefinition(); 6240 } else { 6241 ObjCIvarDecl **ClsFields = 6242 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6243 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6244 ID->setLocEnd(RBrac); 6245 // Add ivar's to class's DeclContext. 6246 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6247 ClsFields[i]->setLexicalDeclContext(ID); 6248 ID->addDecl(ClsFields[i]); 6249 } 6250 // Must enforce the rule that ivars in the base classes may not be 6251 // duplicates. 6252 if (ID->getSuperClass()) 6253 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6254 } else if (ObjCImplementationDecl *IMPDecl = 6255 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6256 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6257 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6258 // Ivar declared in @implementation never belongs to the implementation. 6259 // Only it is in implementation's lexical context. 6260 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6261 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6262 } else if (ObjCCategoryDecl *CDecl = 6263 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6264 // case of ivars in class extension; all other cases have been 6265 // reported as errors elsewhere. 6266 // FIXME. Class extension does not have a LocEnd field. 6267 // CDecl->setLocEnd(RBrac); 6268 // Add ivar's to class extension's DeclContext. 6269 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6270 ClsFields[i]->setLexicalDeclContext(CDecl); 6271 CDecl->addDecl(ClsFields[i]); 6272 } 6273 } 6274 } 6275 6276 if (Attr) 6277 ProcessDeclAttributeList(S, Record, Attr); 6278} 6279 6280/// \brief Determine whether the given integral value is representable within 6281/// the given type T. 6282static bool isRepresentableIntegerValue(ASTContext &Context, 6283 llvm::APSInt &Value, 6284 QualType T) { 6285 assert(T->isIntegralType() && "Integral type required!"); 6286 unsigned BitWidth = Context.getIntWidth(T); 6287 6288 if (Value.isUnsigned() || Value.isNonNegative()) 6289 return Value.getActiveBits() < BitWidth; 6290 6291 return Value.getMinSignedBits() <= BitWidth; 6292} 6293 6294// \brief Given an integral type, return the next larger integral type 6295// (or a NULL type of no such type exists). 6296static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6297 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6298 // enum checking below. 6299 assert(T->isIntegralType() && "Integral type required!"); 6300 const unsigned NumTypes = 4; 6301 QualType SignedIntegralTypes[NumTypes] = { 6302 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6303 }; 6304 QualType UnsignedIntegralTypes[NumTypes] = { 6305 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6306 Context.UnsignedLongLongTy 6307 }; 6308 6309 unsigned BitWidth = Context.getTypeSize(T); 6310 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6311 : UnsignedIntegralTypes; 6312 for (unsigned I = 0; I != NumTypes; ++I) 6313 if (Context.getTypeSize(Types[I]) > BitWidth) 6314 return Types[I]; 6315 6316 return QualType(); 6317} 6318 6319EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6320 EnumConstantDecl *LastEnumConst, 6321 SourceLocation IdLoc, 6322 IdentifierInfo *Id, 6323 ExprArg val) { 6324 Expr *Val = (Expr *)val.get(); 6325 6326 unsigned IntWidth = Context.Target.getIntWidth(); 6327 llvm::APSInt EnumVal(IntWidth); 6328 QualType EltTy; 6329 if (Val) { 6330 if (Enum->isDependentType() || Val->isTypeDependent()) 6331 EltTy = Context.DependentTy; 6332 else { 6333 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6334 SourceLocation ExpLoc; 6335 if (!Val->isValueDependent() && 6336 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6337 Val = 0; 6338 } else { 6339 if (!getLangOptions().CPlusPlus) { 6340 // C99 6.7.2.2p2: 6341 // The expression that defines the value of an enumeration constant 6342 // shall be an integer constant expression that has a value 6343 // representable as an int. 6344 6345 // Complain if the value is not representable in an int. 6346 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6347 Diag(IdLoc, diag::ext_enum_value_not_int) 6348 << EnumVal.toString(10) << Val->getSourceRange() 6349 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6350 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6351 // Force the type of the expression to 'int'. 6352 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6353 6354 if (Val != val.get()) { 6355 val.release(); 6356 val = Val; 6357 } 6358 } 6359 } 6360 6361 // C++0x [dcl.enum]p5: 6362 // If the underlying type is not fixed, the type of each enumerator 6363 // is the type of its initializing value: 6364 // - If an initializer is specified for an enumerator, the 6365 // initializing value has the same type as the expression. 6366 EltTy = Val->getType(); 6367 } 6368 } 6369 } 6370 6371 if (!Val) { 6372 if (Enum->isDependentType()) 6373 EltTy = Context.DependentTy; 6374 else if (!LastEnumConst) { 6375 // C++0x [dcl.enum]p5: 6376 // If the underlying type is not fixed, the type of each enumerator 6377 // is the type of its initializing value: 6378 // - If no initializer is specified for the first enumerator, the 6379 // initializing value has an unspecified integral type. 6380 // 6381 // GCC uses 'int' for its unspecified integral type, as does 6382 // C99 6.7.2.2p3. 6383 EltTy = Context.IntTy; 6384 } else { 6385 // Assign the last value + 1. 6386 EnumVal = LastEnumConst->getInitVal(); 6387 ++EnumVal; 6388 EltTy = LastEnumConst->getType(); 6389 6390 // Check for overflow on increment. 6391 if (EnumVal < LastEnumConst->getInitVal()) { 6392 // C++0x [dcl.enum]p5: 6393 // If the underlying type is not fixed, the type of each enumerator 6394 // is the type of its initializing value: 6395 // 6396 // - Otherwise the type of the initializing value is the same as 6397 // the type of the initializing value of the preceding enumerator 6398 // unless the incremented value is not representable in that type, 6399 // in which case the type is an unspecified integral type 6400 // sufficient to contain the incremented value. If no such type 6401 // exists, the program is ill-formed. 6402 QualType T = getNextLargerIntegralType(Context, EltTy); 6403 if (T.isNull()) { 6404 // There is no integral type larger enough to represent this 6405 // value. Complain, then allow the value to wrap around. 6406 EnumVal = LastEnumConst->getInitVal(); 6407 EnumVal.zext(EnumVal.getBitWidth() * 2); 6408 Diag(IdLoc, diag::warn_enumerator_too_large) 6409 << EnumVal.toString(10); 6410 } else { 6411 EltTy = T; 6412 } 6413 6414 // Retrieve the last enumerator's value, extent that type to the 6415 // type that is supposed to be large enough to represent the incremented 6416 // value, then increment. 6417 EnumVal = LastEnumConst->getInitVal(); 6418 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6419 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6420 ++EnumVal; 6421 6422 // If we're not in C++, diagnose the overflow of enumerator values, 6423 // which in C99 means that the enumerator value is not representable in 6424 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6425 // permits enumerator values that are representable in some larger 6426 // integral type. 6427 if (!getLangOptions().CPlusPlus && !T.isNull()) 6428 Diag(IdLoc, diag::warn_enum_value_overflow); 6429 } else if (!getLangOptions().CPlusPlus && 6430 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6431 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6432 Diag(IdLoc, diag::ext_enum_value_not_int) 6433 << EnumVal.toString(10) << 1; 6434 } 6435 } 6436 } 6437 6438 if (!EltTy->isDependentType()) { 6439 // Make the enumerator value match the signedness and size of the 6440 // enumerator's type. 6441 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6442 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6443 } 6444 6445 val.release(); 6446 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6447 Val, EnumVal); 6448} 6449 6450 6451Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6452 DeclPtrTy lastEnumConst, 6453 SourceLocation IdLoc, 6454 IdentifierInfo *Id, 6455 SourceLocation EqualLoc, ExprTy *val) { 6456 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6457 EnumConstantDecl *LastEnumConst = 6458 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6459 Expr *Val = static_cast<Expr*>(val); 6460 6461 // The scope passed in may not be a decl scope. Zip up the scope tree until 6462 // we find one that is. 6463 S = getNonFieldDeclScope(S); 6464 6465 // Verify that there isn't already something declared with this name in this 6466 // scope. 6467 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6468 ForRedeclaration); 6469 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6470 // Maybe we will complain about the shadowed template parameter. 6471 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6472 // Just pretend that we didn't see the previous declaration. 6473 PrevDecl = 0; 6474 } 6475 6476 if (PrevDecl) { 6477 // When in C++, we may get a TagDecl with the same name; in this case the 6478 // enum constant will 'hide' the tag. 6479 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6480 "Received TagDecl when not in C++!"); 6481 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6482 if (isa<EnumConstantDecl>(PrevDecl)) 6483 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6484 else 6485 Diag(IdLoc, diag::err_redefinition) << Id; 6486 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6487 if (Val) Val->Destroy(Context); 6488 return DeclPtrTy(); 6489 } 6490 } 6491 6492 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6493 IdLoc, Id, Owned(Val)); 6494 6495 // Register this decl in the current scope stack. 6496 if (New) { 6497 New->setAccess(TheEnumDecl->getAccess()); 6498 PushOnScopeChains(New, S); 6499 } 6500 6501 return DeclPtrTy::make(New); 6502} 6503 6504void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6505 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6506 DeclPtrTy *Elements, unsigned NumElements, 6507 Scope *S, AttributeList *Attr) { 6508 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6509 QualType EnumType = Context.getTypeDeclType(Enum); 6510 6511 if (Attr) 6512 ProcessDeclAttributeList(S, Enum, Attr); 6513 6514 if (Enum->isDependentType()) { 6515 for (unsigned i = 0; i != NumElements; ++i) { 6516 EnumConstantDecl *ECD = 6517 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6518 if (!ECD) continue; 6519 6520 ECD->setType(EnumType); 6521 } 6522 6523 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6524 return; 6525 } 6526 6527 // TODO: If the result value doesn't fit in an int, it must be a long or long 6528 // long value. ISO C does not support this, but GCC does as an extension, 6529 // emit a warning. 6530 unsigned IntWidth = Context.Target.getIntWidth(); 6531 unsigned CharWidth = Context.Target.getCharWidth(); 6532 unsigned ShortWidth = Context.Target.getShortWidth(); 6533 6534 // Verify that all the values are okay, compute the size of the values, and 6535 // reverse the list. 6536 unsigned NumNegativeBits = 0; 6537 unsigned NumPositiveBits = 0; 6538 6539 // Keep track of whether all elements have type int. 6540 bool AllElementsInt = true; 6541 6542 for (unsigned i = 0; i != NumElements; ++i) { 6543 EnumConstantDecl *ECD = 6544 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6545 if (!ECD) continue; // Already issued a diagnostic. 6546 6547 const llvm::APSInt &InitVal = ECD->getInitVal(); 6548 6549 // Keep track of the size of positive and negative values. 6550 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6551 NumPositiveBits = std::max(NumPositiveBits, 6552 (unsigned)InitVal.getActiveBits()); 6553 else 6554 NumNegativeBits = std::max(NumNegativeBits, 6555 (unsigned)InitVal.getMinSignedBits()); 6556 6557 // Keep track of whether every enum element has type int (very commmon). 6558 if (AllElementsInt) 6559 AllElementsInt = ECD->getType() == Context.IntTy; 6560 } 6561 6562 // Figure out the type that should be used for this enum. 6563 // FIXME: Support -fshort-enums. 6564 QualType BestType; 6565 unsigned BestWidth; 6566 6567 // C++0x N3000 [conv.prom]p3: 6568 // An rvalue of an unscoped enumeration type whose underlying 6569 // type is not fixed can be converted to an rvalue of the first 6570 // of the following types that can represent all the values of 6571 // the enumeration: int, unsigned int, long int, unsigned long 6572 // int, long long int, or unsigned long long int. 6573 // C99 6.4.4.3p2: 6574 // An identifier declared as an enumeration constant has type int. 6575 // The C99 rule is modified by a gcc extension 6576 QualType BestPromotionType; 6577 6578 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6579 6580 if (NumNegativeBits) { 6581 // If there is a negative value, figure out the smallest integer type (of 6582 // int/long/longlong) that fits. 6583 // If it's packed, check also if it fits a char or a short. 6584 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6585 BestType = Context.SignedCharTy; 6586 BestWidth = CharWidth; 6587 } else if (Packed && NumNegativeBits <= ShortWidth && 6588 NumPositiveBits < ShortWidth) { 6589 BestType = Context.ShortTy; 6590 BestWidth = ShortWidth; 6591 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6592 BestType = Context.IntTy; 6593 BestWidth = IntWidth; 6594 } else { 6595 BestWidth = Context.Target.getLongWidth(); 6596 6597 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6598 BestType = Context.LongTy; 6599 } else { 6600 BestWidth = Context.Target.getLongLongWidth(); 6601 6602 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6603 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6604 BestType = Context.LongLongTy; 6605 } 6606 } 6607 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6608 } else { 6609 // If there is no negative value, figure out the smallest type that fits 6610 // all of the enumerator values. 6611 // If it's packed, check also if it fits a char or a short. 6612 if (Packed && NumPositiveBits <= CharWidth) { 6613 BestType = Context.UnsignedCharTy; 6614 BestPromotionType = Context.IntTy; 6615 BestWidth = CharWidth; 6616 } else if (Packed && NumPositiveBits <= ShortWidth) { 6617 BestType = Context.UnsignedShortTy; 6618 BestPromotionType = Context.IntTy; 6619 BestWidth = ShortWidth; 6620 } else if (NumPositiveBits <= IntWidth) { 6621 BestType = Context.UnsignedIntTy; 6622 BestWidth = IntWidth; 6623 BestPromotionType 6624 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6625 ? Context.UnsignedIntTy : Context.IntTy; 6626 } else if (NumPositiveBits <= 6627 (BestWidth = Context.Target.getLongWidth())) { 6628 BestType = Context.UnsignedLongTy; 6629 BestPromotionType 6630 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6631 ? Context.UnsignedLongTy : Context.LongTy; 6632 } else { 6633 BestWidth = Context.Target.getLongLongWidth(); 6634 assert(NumPositiveBits <= BestWidth && 6635 "How could an initializer get larger than ULL?"); 6636 BestType = Context.UnsignedLongLongTy; 6637 BestPromotionType 6638 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6639 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6640 } 6641 } 6642 6643 // Loop over all of the enumerator constants, changing their types to match 6644 // the type of the enum if needed. 6645 for (unsigned i = 0; i != NumElements; ++i) { 6646 EnumConstantDecl *ECD = 6647 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6648 if (!ECD) continue; // Already issued a diagnostic. 6649 6650 // Standard C says the enumerators have int type, but we allow, as an 6651 // extension, the enumerators to be larger than int size. If each 6652 // enumerator value fits in an int, type it as an int, otherwise type it the 6653 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6654 // that X has type 'int', not 'unsigned'. 6655 6656 // Determine whether the value fits into an int. 6657 llvm::APSInt InitVal = ECD->getInitVal(); 6658 6659 // If it fits into an integer type, force it. Otherwise force it to match 6660 // the enum decl type. 6661 QualType NewTy; 6662 unsigned NewWidth; 6663 bool NewSign; 6664 if (!getLangOptions().CPlusPlus && 6665 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6666 NewTy = Context.IntTy; 6667 NewWidth = IntWidth; 6668 NewSign = true; 6669 } else if (ECD->getType() == BestType) { 6670 // Already the right type! 6671 if (getLangOptions().CPlusPlus) 6672 // C++ [dcl.enum]p4: Following the closing brace of an 6673 // enum-specifier, each enumerator has the type of its 6674 // enumeration. 6675 ECD->setType(EnumType); 6676 continue; 6677 } else { 6678 NewTy = BestType; 6679 NewWidth = BestWidth; 6680 NewSign = BestType->isSignedIntegerType(); 6681 } 6682 6683 // Adjust the APSInt value. 6684 InitVal.extOrTrunc(NewWidth); 6685 InitVal.setIsSigned(NewSign); 6686 ECD->setInitVal(InitVal); 6687 6688 // Adjust the Expr initializer and type. 6689 if (ECD->getInitExpr()) 6690 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6691 CastExpr::CK_IntegralCast, 6692 ECD->getInitExpr(), 6693 CXXBaseSpecifierArray(), 6694 /*isLvalue=*/false)); 6695 if (getLangOptions().CPlusPlus) 6696 // C++ [dcl.enum]p4: Following the closing brace of an 6697 // enum-specifier, each enumerator has the type of its 6698 // enumeration. 6699 ECD->setType(EnumType); 6700 else 6701 ECD->setType(NewTy); 6702 } 6703 6704 Enum->completeDefinition(BestType, BestPromotionType, 6705 NumPositiveBits, NumNegativeBits); 6706} 6707 6708Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6709 ExprArg expr) { 6710 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6711 6712 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6713 Loc, AsmString); 6714 CurContext->addDecl(New); 6715 return DeclPtrTy::make(New); 6716} 6717 6718void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6719 SourceLocation PragmaLoc, 6720 SourceLocation NameLoc) { 6721 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6722 6723 if (PrevDecl) { 6724 PrevDecl->addAttr(::new (Context) WeakAttr()); 6725 } else { 6726 (void)WeakUndeclaredIdentifiers.insert( 6727 std::pair<IdentifierInfo*,WeakInfo> 6728 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6729 } 6730} 6731 6732void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6733 IdentifierInfo* AliasName, 6734 SourceLocation PragmaLoc, 6735 SourceLocation NameLoc, 6736 SourceLocation AliasNameLoc) { 6737 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6738 LookupOrdinaryName); 6739 WeakInfo W = WeakInfo(Name, NameLoc); 6740 6741 if (PrevDecl) { 6742 if (!PrevDecl->hasAttr<AliasAttr>()) 6743 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6744 DeclApplyPragmaWeak(TUScope, ND, W); 6745 } else { 6746 (void)WeakUndeclaredIdentifiers.insert( 6747 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6748 } 6749} 6750