SemaDecl.cpp revision aef01998af5bbfc1cdfac091248ff7d30ec31456
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(S, 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() && !NewType->getNoReturnAttr()) { 1061 NewQType = Context.getNoReturnType(NewQType); 1062 New->setType(NewQType); 1063 assert(NewQType.isCanonical()); 1064 } 1065 1066 // Merge regparm attribute. 1067 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1068 if (NewType->getRegParmType()) { 1069 Diag(New->getLocation(), diag::err_regparm_mismatch) 1070 << NewType->getRegParmType() 1071 << OldType->getRegParmType(); 1072 Diag(Old->getLocation(), diag::note_previous_declaration); 1073 return true; 1074 } 1075 1076 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1077 New->setType(NewQType); 1078 assert(NewQType.isCanonical()); 1079 } 1080 1081 if (getLangOptions().CPlusPlus) { 1082 // (C++98 13.1p2): 1083 // Certain function declarations cannot be overloaded: 1084 // -- Function declarations that differ only in the return type 1085 // cannot be overloaded. 1086 QualType OldReturnType 1087 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1088 QualType NewReturnType 1089 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1090 QualType ResQT; 1091 if (OldReturnType != NewReturnType) { 1092 if (NewReturnType->isObjCObjectPointerType() 1093 && OldReturnType->isObjCObjectPointerType()) 1094 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1095 if (ResQT.isNull()) { 1096 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1097 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1098 return true; 1099 } 1100 else 1101 NewQType = ResQT; 1102 } 1103 1104 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1105 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1106 if (OldMethod && NewMethod) { 1107 // Preserve triviality. 1108 NewMethod->setTrivial(OldMethod->isTrivial()); 1109 1110 bool isFriend = NewMethod->getFriendObjectKind(); 1111 1112 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1113 // -- Member function declarations with the same name and the 1114 // same parameter types cannot be overloaded if any of them 1115 // is a static member function declaration. 1116 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1117 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1118 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1119 return true; 1120 } 1121 1122 // C++ [class.mem]p1: 1123 // [...] A member shall not be declared twice in the 1124 // member-specification, except that a nested class or member 1125 // class template can be declared and then later defined. 1126 unsigned NewDiag; 1127 if (isa<CXXConstructorDecl>(OldMethod)) 1128 NewDiag = diag::err_constructor_redeclared; 1129 else if (isa<CXXDestructorDecl>(NewMethod)) 1130 NewDiag = diag::err_destructor_redeclared; 1131 else if (isa<CXXConversionDecl>(NewMethod)) 1132 NewDiag = diag::err_conv_function_redeclared; 1133 else 1134 NewDiag = diag::err_member_redeclared; 1135 1136 Diag(New->getLocation(), NewDiag); 1137 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1138 1139 // Complain if this is an explicit declaration of a special 1140 // member that was initially declared implicitly. 1141 // 1142 // As an exception, it's okay to befriend such methods in order 1143 // to permit the implicit constructor/destructor/operator calls. 1144 } else if (OldMethod->isImplicit()) { 1145 if (isFriend) { 1146 NewMethod->setImplicit(); 1147 } else { 1148 Diag(NewMethod->getLocation(), 1149 diag::err_definition_of_implicitly_declared_member) 1150 << New << getSpecialMember(OldMethod); 1151 return true; 1152 } 1153 } 1154 } 1155 1156 // (C++98 8.3.5p3): 1157 // All declarations for a function shall agree exactly in both the 1158 // return type and the parameter-type-list. 1159 // attributes should be ignored when comparing. 1160 if (Context.getNoReturnType(OldQType, false) == 1161 Context.getNoReturnType(NewQType, false)) 1162 return MergeCompatibleFunctionDecls(New, Old); 1163 1164 // Fall through for conflicting redeclarations and redefinitions. 1165 } 1166 1167 // C: Function types need to be compatible, not identical. This handles 1168 // duplicate function decls like "void f(int); void f(enum X);" properly. 1169 if (!getLangOptions().CPlusPlus && 1170 Context.typesAreCompatible(OldQType, NewQType)) { 1171 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1172 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1173 const FunctionProtoType *OldProto = 0; 1174 if (isa<FunctionNoProtoType>(NewFuncType) && 1175 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1176 // The old declaration provided a function prototype, but the 1177 // new declaration does not. Merge in the prototype. 1178 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1179 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1180 OldProto->arg_type_end()); 1181 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1182 ParamTypes.data(), ParamTypes.size(), 1183 OldProto->isVariadic(), 1184 OldProto->getTypeQuals(), 1185 false, false, 0, 0, 1186 OldProto->getExtInfo()); 1187 New->setType(NewQType); 1188 New->setHasInheritedPrototype(); 1189 1190 // Synthesize a parameter for each argument type. 1191 llvm::SmallVector<ParmVarDecl*, 16> Params; 1192 for (FunctionProtoType::arg_type_iterator 1193 ParamType = OldProto->arg_type_begin(), 1194 ParamEnd = OldProto->arg_type_end(); 1195 ParamType != ParamEnd; ++ParamType) { 1196 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1197 SourceLocation(), 0, 1198 *ParamType, /*TInfo=*/0, 1199 VarDecl::None, VarDecl::None, 1200 0); 1201 Param->setImplicit(); 1202 Params.push_back(Param); 1203 } 1204 1205 New->setParams(Params.data(), Params.size()); 1206 } 1207 1208 return MergeCompatibleFunctionDecls(New, Old); 1209 } 1210 1211 // GNU C permits a K&R definition to follow a prototype declaration 1212 // if the declared types of the parameters in the K&R definition 1213 // match the types in the prototype declaration, even when the 1214 // promoted types of the parameters from the K&R definition differ 1215 // from the types in the prototype. GCC then keeps the types from 1216 // the prototype. 1217 // 1218 // If a variadic prototype is followed by a non-variadic K&R definition, 1219 // the K&R definition becomes variadic. This is sort of an edge case, but 1220 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1221 // C99 6.9.1p8. 1222 if (!getLangOptions().CPlusPlus && 1223 Old->hasPrototype() && !New->hasPrototype() && 1224 New->getType()->getAs<FunctionProtoType>() && 1225 Old->getNumParams() == New->getNumParams()) { 1226 llvm::SmallVector<QualType, 16> ArgTypes; 1227 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1228 const FunctionProtoType *OldProto 1229 = Old->getType()->getAs<FunctionProtoType>(); 1230 const FunctionProtoType *NewProto 1231 = New->getType()->getAs<FunctionProtoType>(); 1232 1233 // Determine whether this is the GNU C extension. 1234 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1235 NewProto->getResultType()); 1236 bool LooseCompatible = !MergedReturn.isNull(); 1237 for (unsigned Idx = 0, End = Old->getNumParams(); 1238 LooseCompatible && Idx != End; ++Idx) { 1239 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1240 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1241 if (Context.typesAreCompatible(OldParm->getType(), 1242 NewProto->getArgType(Idx))) { 1243 ArgTypes.push_back(NewParm->getType()); 1244 } else if (Context.typesAreCompatible(OldParm->getType(), 1245 NewParm->getType())) { 1246 GNUCompatibleParamWarning Warn 1247 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1248 Warnings.push_back(Warn); 1249 ArgTypes.push_back(NewParm->getType()); 1250 } else 1251 LooseCompatible = false; 1252 } 1253 1254 if (LooseCompatible) { 1255 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1256 Diag(Warnings[Warn].NewParm->getLocation(), 1257 diag::ext_param_promoted_not_compatible_with_prototype) 1258 << Warnings[Warn].PromotedType 1259 << Warnings[Warn].OldParm->getType(); 1260 Diag(Warnings[Warn].OldParm->getLocation(), 1261 diag::note_previous_declaration); 1262 } 1263 1264 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1265 ArgTypes.size(), 1266 OldProto->isVariadic(), 0, 1267 false, false, 0, 0, 1268 OldProto->getExtInfo())); 1269 return MergeCompatibleFunctionDecls(New, Old); 1270 } 1271 1272 // Fall through to diagnose conflicting types. 1273 } 1274 1275 // A function that has already been declared has been redeclared or defined 1276 // with a different type- show appropriate diagnostic 1277 if (unsigned BuiltinID = Old->getBuiltinID()) { 1278 // The user has declared a builtin function with an incompatible 1279 // signature. 1280 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1281 // The function the user is redeclaring is a library-defined 1282 // function like 'malloc' or 'printf'. Warn about the 1283 // redeclaration, then pretend that we don't know about this 1284 // library built-in. 1285 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1286 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1287 << Old << Old->getType(); 1288 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1289 Old->setInvalidDecl(); 1290 return false; 1291 } 1292 1293 PrevDiag = diag::note_previous_builtin_declaration; 1294 } 1295 1296 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1297 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1298 return true; 1299} 1300 1301/// \brief Completes the merge of two function declarations that are 1302/// known to be compatible. 1303/// 1304/// This routine handles the merging of attributes and other 1305/// properties of function declarations form the old declaration to 1306/// the new declaration, once we know that New is in fact a 1307/// redeclaration of Old. 1308/// 1309/// \returns false 1310bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1311 // Merge the attributes 1312 MergeAttributes(New, Old, Context); 1313 1314 // Merge the storage class. 1315 if (Old->getStorageClass() != FunctionDecl::Extern && 1316 Old->getStorageClass() != FunctionDecl::None) 1317 New->setStorageClass(Old->getStorageClass()); 1318 1319 // Merge "pure" flag. 1320 if (Old->isPure()) 1321 New->setPure(); 1322 1323 // Merge the "deleted" flag. 1324 if (Old->isDeleted()) 1325 New->setDeleted(); 1326 1327 if (getLangOptions().CPlusPlus) 1328 return MergeCXXFunctionDecl(New, Old); 1329 1330 return false; 1331} 1332 1333/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1334/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1335/// situation, merging decls or emitting diagnostics as appropriate. 1336/// 1337/// Tentative definition rules (C99 6.9.2p2) are checked by 1338/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1339/// definitions here, since the initializer hasn't been attached. 1340/// 1341void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1342 // If the new decl is already invalid, don't do any other checking. 1343 if (New->isInvalidDecl()) 1344 return; 1345 1346 // Verify the old decl was also a variable. 1347 VarDecl *Old = 0; 1348 if (!Previous.isSingleResult() || 1349 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1350 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1351 << New->getDeclName(); 1352 Diag(Previous.getRepresentativeDecl()->getLocation(), 1353 diag::note_previous_definition); 1354 return New->setInvalidDecl(); 1355 } 1356 1357 MergeAttributes(New, Old, Context); 1358 1359 // Merge the types 1360 QualType MergedT; 1361 if (getLangOptions().CPlusPlus) { 1362 if (Context.hasSameType(New->getType(), Old->getType())) 1363 MergedT = New->getType(); 1364 // C++ [basic.link]p10: 1365 // [...] the types specified by all declarations referring to a given 1366 // object or function shall be identical, except that declarations for an 1367 // array object can specify array types that differ by the presence or 1368 // absence of a major array bound (8.3.4). 1369 else if (Old->getType()->isIncompleteArrayType() && 1370 New->getType()->isArrayType()) { 1371 CanQual<ArrayType> OldArray 1372 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1373 CanQual<ArrayType> NewArray 1374 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1375 if (OldArray->getElementType() == NewArray->getElementType()) 1376 MergedT = New->getType(); 1377 } else if (Old->getType()->isArrayType() && 1378 New->getType()->isIncompleteArrayType()) { 1379 CanQual<ArrayType> OldArray 1380 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1381 CanQual<ArrayType> NewArray 1382 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1383 if (OldArray->getElementType() == NewArray->getElementType()) 1384 MergedT = Old->getType(); 1385 } else if (New->getType()->isObjCObjectPointerType() 1386 && Old->getType()->isObjCObjectPointerType()) { 1387 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1388 } 1389 } else { 1390 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1391 } 1392 if (MergedT.isNull()) { 1393 Diag(New->getLocation(), diag::err_redefinition_different_type) 1394 << New->getDeclName(); 1395 Diag(Old->getLocation(), diag::note_previous_definition); 1396 return New->setInvalidDecl(); 1397 } 1398 New->setType(MergedT); 1399 1400 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1401 if (New->getStorageClass() == VarDecl::Static && 1402 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1403 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1404 Diag(Old->getLocation(), diag::note_previous_definition); 1405 return New->setInvalidDecl(); 1406 } 1407 // C99 6.2.2p4: 1408 // For an identifier declared with the storage-class specifier 1409 // extern in a scope in which a prior declaration of that 1410 // identifier is visible,23) if the prior declaration specifies 1411 // internal or external linkage, the linkage of the identifier at 1412 // the later declaration is the same as the linkage specified at 1413 // the prior declaration. If no prior declaration is visible, or 1414 // if the prior declaration specifies no linkage, then the 1415 // identifier has external linkage. 1416 if (New->hasExternalStorage() && Old->hasLinkage()) 1417 /* Okay */; 1418 else if (New->getStorageClass() != VarDecl::Static && 1419 Old->getStorageClass() == VarDecl::Static) { 1420 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1421 Diag(Old->getLocation(), diag::note_previous_definition); 1422 return New->setInvalidDecl(); 1423 } 1424 1425 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1426 1427 // FIXME: The test for external storage here seems wrong? We still 1428 // need to check for mismatches. 1429 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1430 // Don't complain about out-of-line definitions of static members. 1431 !(Old->getLexicalDeclContext()->isRecord() && 1432 !New->getLexicalDeclContext()->isRecord())) { 1433 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1434 Diag(Old->getLocation(), diag::note_previous_definition); 1435 return New->setInvalidDecl(); 1436 } 1437 1438 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1439 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1440 Diag(Old->getLocation(), diag::note_previous_definition); 1441 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1442 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1443 Diag(Old->getLocation(), diag::note_previous_definition); 1444 } 1445 1446 // C++ doesn't have tentative definitions, so go right ahead and check here. 1447 const VarDecl *Def; 1448 if (getLangOptions().CPlusPlus && 1449 New->isThisDeclarationADefinition() == VarDecl::Definition && 1450 (Def = Old->getDefinition())) { 1451 Diag(New->getLocation(), diag::err_redefinition) 1452 << New->getDeclName(); 1453 Diag(Def->getLocation(), diag::note_previous_definition); 1454 New->setInvalidDecl(); 1455 return; 1456 } 1457 // c99 6.2.2 P4. 1458 // For an identifier declared with the storage-class specifier extern in a 1459 // scope in which a prior declaration of that identifier is visible, if 1460 // the prior declaration specifies internal or external linkage, the linkage 1461 // of the identifier at the later declaration is the same as the linkage 1462 // specified at the prior declaration. 1463 // FIXME. revisit this code. 1464 if (New->hasExternalStorage() && 1465 Old->getLinkage() == InternalLinkage && 1466 New->getDeclContext() == Old->getDeclContext()) 1467 New->setStorageClass(Old->getStorageClass()); 1468 1469 // Keep a chain of previous declarations. 1470 New->setPreviousDeclaration(Old); 1471 1472 // Inherit access appropriately. 1473 New->setAccess(Old->getAccess()); 1474} 1475 1476/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1477/// no declarator (e.g. "struct foo;") is parsed. 1478Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1479 DeclSpec &DS) { 1480 // FIXME: Error on auto/register at file scope 1481 // FIXME: Error on inline/virtual/explicit 1482 // FIXME: Warn on useless __thread 1483 // FIXME: Warn on useless const/volatile 1484 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1485 // FIXME: Warn on useless attributes 1486 Decl *TagD = 0; 1487 TagDecl *Tag = 0; 1488 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1489 DS.getTypeSpecType() == DeclSpec::TST_struct || 1490 DS.getTypeSpecType() == DeclSpec::TST_union || 1491 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1492 TagD = static_cast<Decl *>(DS.getTypeRep()); 1493 1494 if (!TagD) // We probably had an error 1495 return DeclPtrTy(); 1496 1497 // Note that the above type specs guarantee that the 1498 // type rep is a Decl, whereas in many of the others 1499 // it's a Type. 1500 Tag = dyn_cast<TagDecl>(TagD); 1501 } 1502 1503 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1504 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1505 // or incomplete types shall not be restrict-qualified." 1506 if (TypeQuals & DeclSpec::TQ_restrict) 1507 Diag(DS.getRestrictSpecLoc(), 1508 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1509 << DS.getSourceRange(); 1510 } 1511 1512 if (DS.isFriendSpecified()) { 1513 // If we're dealing with a class template decl, assume that the 1514 // template routines are handling it. 1515 if (TagD && isa<ClassTemplateDecl>(TagD)) 1516 return DeclPtrTy(); 1517 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1518 } 1519 1520 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1521 // If there are attributes in the DeclSpec, apply them to the record. 1522 if (const AttributeList *AL = DS.getAttributes()) 1523 ProcessDeclAttributeList(S, Record, AL); 1524 1525 if (!Record->getDeclName() && Record->isDefinition() && 1526 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1527 if (getLangOptions().CPlusPlus || 1528 Record->getDeclContext()->isRecord()) 1529 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1530 1531 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1532 << DS.getSourceRange(); 1533 } 1534 1535 // Microsoft allows unnamed struct/union fields. Don't complain 1536 // about them. 1537 // FIXME: Should we support Microsoft's extensions in this area? 1538 if (Record->getDeclName() && getLangOptions().Microsoft) 1539 return DeclPtrTy::make(Tag); 1540 } 1541 1542 if (getLangOptions().CPlusPlus && 1543 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1544 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1545 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1546 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1547 Diag(Enum->getLocation(), diag::ext_no_declarators) 1548 << DS.getSourceRange(); 1549 1550 if (!DS.isMissingDeclaratorOk() && 1551 DS.getTypeSpecType() != DeclSpec::TST_error) { 1552 // Warn about typedefs of enums without names, since this is an 1553 // extension in both Microsoft an GNU. 1554 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1555 Tag && isa<EnumDecl>(Tag)) { 1556 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1557 << DS.getSourceRange(); 1558 return DeclPtrTy::make(Tag); 1559 } 1560 1561 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1562 << DS.getSourceRange(); 1563 } 1564 1565 return DeclPtrTy::make(Tag); 1566} 1567 1568/// We are trying to inject an anonymous member into the given scope; 1569/// check if there's an existing declaration that can't be overloaded. 1570/// 1571/// \return true if this is a forbidden redeclaration 1572static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1573 Scope *S, 1574 DeclContext *Owner, 1575 DeclarationName Name, 1576 SourceLocation NameLoc, 1577 unsigned diagnostic) { 1578 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1579 Sema::ForRedeclaration); 1580 if (!SemaRef.LookupName(R, S)) return false; 1581 1582 if (R.getAsSingle<TagDecl>()) 1583 return false; 1584 1585 // Pick a representative declaration. 1586 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1587 if (PrevDecl && Owner->isRecord()) { 1588 RecordDecl *Record = cast<RecordDecl>(Owner); 1589 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1590 return false; 1591 } 1592 1593 SemaRef.Diag(NameLoc, diagnostic) << Name; 1594 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1595 1596 return true; 1597} 1598 1599/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1600/// anonymous struct or union AnonRecord into the owning context Owner 1601/// and scope S. This routine will be invoked just after we realize 1602/// that an unnamed union or struct is actually an anonymous union or 1603/// struct, e.g., 1604/// 1605/// @code 1606/// union { 1607/// int i; 1608/// float f; 1609/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1610/// // f into the surrounding scope.x 1611/// @endcode 1612/// 1613/// This routine is recursive, injecting the names of nested anonymous 1614/// structs/unions into the owning context and scope as well. 1615static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1616 DeclContext *Owner, 1617 RecordDecl *AnonRecord, 1618 AccessSpecifier AS) { 1619 unsigned diagKind 1620 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1621 : diag::err_anonymous_struct_member_redecl; 1622 1623 bool Invalid = false; 1624 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1625 FEnd = AnonRecord->field_end(); 1626 F != FEnd; ++F) { 1627 if ((*F)->getDeclName()) { 1628 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1629 (*F)->getLocation(), diagKind)) { 1630 // C++ [class.union]p2: 1631 // The names of the members of an anonymous union shall be 1632 // distinct from the names of any other entity in the 1633 // scope in which the anonymous union is declared. 1634 Invalid = true; 1635 } else { 1636 // C++ [class.union]p2: 1637 // For the purpose of name lookup, after the anonymous union 1638 // definition, the members of the anonymous union are 1639 // considered to have been defined in the scope in which the 1640 // anonymous union is declared. 1641 Owner->makeDeclVisibleInContext(*F); 1642 S->AddDecl(Sema::DeclPtrTy::make(*F)); 1643 SemaRef.IdResolver.AddDecl(*F); 1644 1645 // That includes picking up the appropriate access specifier. 1646 if (AS != AS_none) (*F)->setAccess(AS); 1647 } 1648 } else if (const RecordType *InnerRecordType 1649 = (*F)->getType()->getAs<RecordType>()) { 1650 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1651 if (InnerRecord->isAnonymousStructOrUnion()) 1652 Invalid = Invalid || 1653 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1654 InnerRecord, AS); 1655 } 1656 } 1657 1658 return Invalid; 1659} 1660 1661/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1662/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1663/// illegal input values are mapped to VarDecl::None. 1664/// If the input declaration context is a linkage specification 1665/// with no braces, then Extern is mapped to None. 1666static VarDecl::StorageClass 1667StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1668 DeclContext *DC) { 1669 switch (StorageClassSpec) { 1670 case DeclSpec::SCS_unspecified: return VarDecl::None; 1671 case DeclSpec::SCS_extern: 1672 // If the current context is a C++ linkage specification 1673 // having no braces, then the keyword "extern" is properly part 1674 // of the linkage specification itself, rather than being 1675 // the written storage class specifier. 1676 return (DC && isa<LinkageSpecDecl>(DC) && 1677 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1678 ? VarDecl::None : VarDecl::Extern; 1679 case DeclSpec::SCS_static: return VarDecl::Static; 1680 case DeclSpec::SCS_auto: return VarDecl::Auto; 1681 case DeclSpec::SCS_register: return VarDecl::Register; 1682 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1683 // Illegal SCSs map to None: error reporting is up to the caller. 1684 case DeclSpec::SCS_mutable: // Fall through. 1685 case DeclSpec::SCS_typedef: return VarDecl::None; 1686 } 1687 llvm_unreachable("unknown storage class specifier"); 1688} 1689 1690/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1691/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1692/// illegal input values are mapped to FunctionDecl::None. 1693/// If the input declaration context is a linkage specification 1694/// with no braces, then Extern is mapped to None. 1695static FunctionDecl::StorageClass 1696StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1697 DeclContext *DC) { 1698 switch (StorageClassSpec) { 1699 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1700 case DeclSpec::SCS_extern: 1701 // If the current context is a C++ linkage specification 1702 // having no braces, then the keyword "extern" is properly part 1703 // of the linkage specification itself, rather than being 1704 // the written storage class specifier. 1705 return (DC && isa<LinkageSpecDecl>(DC) && 1706 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1707 ? FunctionDecl::None : FunctionDecl::Extern; 1708 case DeclSpec::SCS_static: return FunctionDecl::Static; 1709 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1710 // Illegal SCSs map to None: error reporting is up to the caller. 1711 case DeclSpec::SCS_auto: // Fall through. 1712 case DeclSpec::SCS_mutable: // Fall through. 1713 case DeclSpec::SCS_register: // Fall through. 1714 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1715 } 1716 llvm_unreachable("unknown storage class specifier"); 1717} 1718 1719/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1720/// anonymous structure or union. Anonymous unions are a C++ feature 1721/// (C++ [class.union]) and a GNU C extension; anonymous structures 1722/// are a GNU C and GNU C++ extension. 1723Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1724 AccessSpecifier AS, 1725 RecordDecl *Record) { 1726 DeclContext *Owner = Record->getDeclContext(); 1727 1728 // Diagnose whether this anonymous struct/union is an extension. 1729 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1730 Diag(Record->getLocation(), diag::ext_anonymous_union); 1731 else if (!Record->isUnion()) 1732 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1733 1734 // C and C++ require different kinds of checks for anonymous 1735 // structs/unions. 1736 bool Invalid = false; 1737 if (getLangOptions().CPlusPlus) { 1738 const char* PrevSpec = 0; 1739 unsigned DiagID; 1740 // C++ [class.union]p3: 1741 // Anonymous unions declared in a named namespace or in the 1742 // global namespace shall be declared static. 1743 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1744 (isa<TranslationUnitDecl>(Owner) || 1745 (isa<NamespaceDecl>(Owner) && 1746 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1747 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1748 Invalid = true; 1749 1750 // Recover by adding 'static'. 1751 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1752 PrevSpec, DiagID); 1753 } 1754 // C++ [class.union]p3: 1755 // A storage class is not allowed in a declaration of an 1756 // anonymous union in a class scope. 1757 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1758 isa<RecordDecl>(Owner)) { 1759 Diag(DS.getStorageClassSpecLoc(), 1760 diag::err_anonymous_union_with_storage_spec); 1761 Invalid = true; 1762 1763 // Recover by removing the storage specifier. 1764 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1765 PrevSpec, DiagID); 1766 } 1767 1768 // C++ [class.union]p2: 1769 // The member-specification of an anonymous union shall only 1770 // define non-static data members. [Note: nested types and 1771 // functions cannot be declared within an anonymous union. ] 1772 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1773 MemEnd = Record->decls_end(); 1774 Mem != MemEnd; ++Mem) { 1775 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1776 // C++ [class.union]p3: 1777 // An anonymous union shall not have private or protected 1778 // members (clause 11). 1779 assert(FD->getAccess() != AS_none); 1780 if (FD->getAccess() != AS_public) { 1781 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1782 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1783 Invalid = true; 1784 } 1785 } else if ((*Mem)->isImplicit()) { 1786 // Any implicit members are fine. 1787 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1788 // This is a type that showed up in an 1789 // elaborated-type-specifier inside the anonymous struct or 1790 // union, but which actually declares a type outside of the 1791 // anonymous struct or union. It's okay. 1792 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1793 if (!MemRecord->isAnonymousStructOrUnion() && 1794 MemRecord->getDeclName()) { 1795 // This is a nested type declaration. 1796 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1797 << (int)Record->isUnion(); 1798 Invalid = true; 1799 } 1800 } else if (isa<AccessSpecDecl>(*Mem)) { 1801 // Any access specifier is fine. 1802 } else { 1803 // We have something that isn't a non-static data 1804 // member. Complain about it. 1805 unsigned DK = diag::err_anonymous_record_bad_member; 1806 if (isa<TypeDecl>(*Mem)) 1807 DK = diag::err_anonymous_record_with_type; 1808 else if (isa<FunctionDecl>(*Mem)) 1809 DK = diag::err_anonymous_record_with_function; 1810 else if (isa<VarDecl>(*Mem)) 1811 DK = diag::err_anonymous_record_with_static; 1812 Diag((*Mem)->getLocation(), DK) 1813 << (int)Record->isUnion(); 1814 Invalid = true; 1815 } 1816 } 1817 } 1818 1819 if (!Record->isUnion() && !Owner->isRecord()) { 1820 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1821 << (int)getLangOptions().CPlusPlus; 1822 Invalid = true; 1823 } 1824 1825 // Mock up a declarator. 1826 Declarator Dc(DS, Declarator::TypeNameContext); 1827 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1828 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1829 1830 // Create a declaration for this anonymous struct/union. 1831 NamedDecl *Anon = 0; 1832 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1833 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1834 /*IdentifierInfo=*/0, 1835 Context.getTypeDeclType(Record), 1836 TInfo, 1837 /*BitWidth=*/0, /*Mutable=*/false); 1838 Anon->setAccess(AS); 1839 if (getLangOptions().CPlusPlus) { 1840 FieldCollector->Add(cast<FieldDecl>(Anon)); 1841 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1842 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1843 } 1844 } else { 1845 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1846 assert(SCSpec != DeclSpec::SCS_typedef && 1847 "Parser allowed 'typedef' as storage class VarDecl."); 1848 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1849 if (SCSpec == DeclSpec::SCS_mutable) { 1850 // mutable can only appear on non-static class members, so it's always 1851 // an error here 1852 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1853 Invalid = true; 1854 SC = VarDecl::None; 1855 } 1856 SCSpec = DS.getStorageClassSpecAsWritten(); 1857 VarDecl::StorageClass SCAsWritten 1858 = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1859 1860 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1861 /*IdentifierInfo=*/0, 1862 Context.getTypeDeclType(Record), 1863 TInfo, SC, SCAsWritten); 1864 } 1865 Anon->setImplicit(); 1866 1867 // Add the anonymous struct/union object to the current 1868 // context. We'll be referencing this object when we refer to one of 1869 // its members. 1870 Owner->addDecl(Anon); 1871 1872 // Inject the members of the anonymous struct/union into the owning 1873 // context and into the identifier resolver chain for name lookup 1874 // purposes. 1875 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1876 Invalid = true; 1877 1878 // Mark this as an anonymous struct/union type. Note that we do not 1879 // do this until after we have already checked and injected the 1880 // members of this anonymous struct/union type, because otherwise 1881 // the members could be injected twice: once by DeclContext when it 1882 // builds its lookup table, and once by 1883 // InjectAnonymousStructOrUnionMembers. 1884 Record->setAnonymousStructOrUnion(true); 1885 1886 if (Invalid) 1887 Anon->setInvalidDecl(); 1888 1889 return DeclPtrTy::make(Anon); 1890} 1891 1892 1893/// GetNameForDeclarator - Determine the full declaration name for the 1894/// given Declarator. 1895DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1896 return GetNameFromUnqualifiedId(D.getName()); 1897} 1898 1899/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1900DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1901 switch (Name.getKind()) { 1902 case UnqualifiedId::IK_Identifier: 1903 return DeclarationName(Name.Identifier); 1904 1905 case UnqualifiedId::IK_OperatorFunctionId: 1906 return Context.DeclarationNames.getCXXOperatorName( 1907 Name.OperatorFunctionId.Operator); 1908 1909 case UnqualifiedId::IK_LiteralOperatorId: 1910 return Context.DeclarationNames.getCXXLiteralOperatorName( 1911 Name.Identifier); 1912 1913 case UnqualifiedId::IK_ConversionFunctionId: { 1914 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1915 if (Ty.isNull()) 1916 return DeclarationName(); 1917 1918 return Context.DeclarationNames.getCXXConversionFunctionName( 1919 Context.getCanonicalType(Ty)); 1920 } 1921 1922 case UnqualifiedId::IK_ConstructorName: { 1923 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1924 if (Ty.isNull()) 1925 return DeclarationName(); 1926 1927 return Context.DeclarationNames.getCXXConstructorName( 1928 Context.getCanonicalType(Ty)); 1929 } 1930 1931 case UnqualifiedId::IK_ConstructorTemplateId: { 1932 // In well-formed code, we can only have a constructor 1933 // template-id that refers to the current context, so go there 1934 // to find the actual type being constructed. 1935 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1936 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1937 return DeclarationName(); 1938 1939 // Determine the type of the class being constructed. 1940 QualType CurClassType = Context.getTypeDeclType(CurClass); 1941 1942 // FIXME: Check two things: that the template-id names the same type as 1943 // CurClassType, and that the template-id does not occur when the name 1944 // was qualified. 1945 1946 return Context.DeclarationNames.getCXXConstructorName( 1947 Context.getCanonicalType(CurClassType)); 1948 } 1949 1950 case UnqualifiedId::IK_DestructorName: { 1951 QualType Ty = GetTypeFromParser(Name.DestructorName); 1952 if (Ty.isNull()) 1953 return DeclarationName(); 1954 1955 return Context.DeclarationNames.getCXXDestructorName( 1956 Context.getCanonicalType(Ty)); 1957 } 1958 1959 case UnqualifiedId::IK_TemplateId: { 1960 TemplateName TName 1961 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1962 return Context.getNameForTemplate(TName); 1963 } 1964 } 1965 1966 assert(false && "Unknown name kind"); 1967 return DeclarationName(); 1968} 1969 1970/// isNearlyMatchingFunction - Determine whether the C++ functions 1971/// Declaration and Definition are "nearly" matching. This heuristic 1972/// is used to improve diagnostics in the case where an out-of-line 1973/// function definition doesn't match any declaration within 1974/// the class or namespace. 1975static bool isNearlyMatchingFunction(ASTContext &Context, 1976 FunctionDecl *Declaration, 1977 FunctionDecl *Definition) { 1978 if (Declaration->param_size() != Definition->param_size()) 1979 return false; 1980 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1981 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1982 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1983 1984 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1985 DefParamTy.getNonReferenceType())) 1986 return false; 1987 } 1988 1989 return true; 1990} 1991 1992/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 1993/// declarator needs to be rebuilt in the current instantiation. 1994/// Any bits of declarator which appear before the name are valid for 1995/// consideration here. That's specifically the type in the decl spec 1996/// and the base type in any member-pointer chunks. 1997static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 1998 DeclarationName Name) { 1999 // The types we specifically need to rebuild are: 2000 // - typenames, typeofs, and decltypes 2001 // - types which will become injected class names 2002 // Of course, we also need to rebuild any type referencing such a 2003 // type. It's safest to just say "dependent", but we call out a 2004 // few cases here. 2005 2006 DeclSpec &DS = D.getMutableDeclSpec(); 2007 switch (DS.getTypeSpecType()) { 2008 case DeclSpec::TST_typename: 2009 case DeclSpec::TST_typeofType: 2010 case DeclSpec::TST_typeofExpr: 2011 case DeclSpec::TST_decltype: { 2012 // Grab the type from the parser. 2013 TypeSourceInfo *TSI = 0; 2014 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 2015 if (T.isNull() || !T->isDependentType()) break; 2016 2017 // Make sure there's a type source info. This isn't really much 2018 // of a waste; most dependent types should have type source info 2019 // attached already. 2020 if (!TSI) 2021 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2022 2023 // Rebuild the type in the current instantiation. 2024 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2025 if (!TSI) return true; 2026 2027 // Store the new type back in the decl spec. 2028 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2029 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2030 break; 2031 } 2032 2033 default: 2034 // Nothing to do for these decl specs. 2035 break; 2036 } 2037 2038 // It doesn't matter what order we do this in. 2039 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2040 DeclaratorChunk &Chunk = D.getTypeObject(I); 2041 2042 // The only type information in the declarator which can come 2043 // before the declaration name is the base type of a member 2044 // pointer. 2045 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2046 continue; 2047 2048 // Rebuild the scope specifier in-place. 2049 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2050 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2051 return true; 2052 } 2053 2054 return false; 2055} 2056 2057Sema::DeclPtrTy 2058Sema::HandleDeclarator(Scope *S, Declarator &D, 2059 MultiTemplateParamsArg TemplateParamLists, 2060 bool IsFunctionDefinition) { 2061 DeclarationName Name = GetNameForDeclarator(D); 2062 2063 // All of these full declarators require an identifier. If it doesn't have 2064 // one, the ParsedFreeStandingDeclSpec action should be used. 2065 if (!Name) { 2066 if (!D.isInvalidType()) // Reject this if we think it is valid. 2067 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2068 diag::err_declarator_need_ident) 2069 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2070 return DeclPtrTy(); 2071 } 2072 2073 // The scope passed in may not be a decl scope. Zip up the scope tree until 2074 // we find one that is. 2075 while ((S->getFlags() & Scope::DeclScope) == 0 || 2076 (S->getFlags() & Scope::TemplateParamScope) != 0) 2077 S = S->getParent(); 2078 2079 DeclContext *DC = CurContext; 2080 if (D.getCXXScopeSpec().isInvalid()) 2081 D.setInvalidType(); 2082 else if (D.getCXXScopeSpec().isSet()) { 2083 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2084 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2085 if (!DC) { 2086 // If we could not compute the declaration context, it's because the 2087 // declaration context is dependent but does not refer to a class, 2088 // class template, or class template partial specialization. Complain 2089 // and return early, to avoid the coming semantic disaster. 2090 Diag(D.getIdentifierLoc(), 2091 diag::err_template_qualified_declarator_no_match) 2092 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2093 << D.getCXXScopeSpec().getRange(); 2094 return DeclPtrTy(); 2095 } 2096 2097 bool IsDependentContext = DC->isDependentContext(); 2098 2099 if (!IsDependentContext && 2100 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2101 return DeclPtrTy(); 2102 2103 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2104 Diag(D.getIdentifierLoc(), 2105 diag::err_member_def_undefined_record) 2106 << Name << DC << D.getCXXScopeSpec().getRange(); 2107 D.setInvalidType(); 2108 } 2109 2110 // Check whether we need to rebuild the type of the given 2111 // declaration in the current instantiation. 2112 if (EnteringContext && IsDependentContext && 2113 TemplateParamLists.size() != 0) { 2114 ContextRAII SavedContext(*this, DC); 2115 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2116 D.setInvalidType(); 2117 } 2118 } 2119 2120 NamedDecl *New; 2121 2122 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2123 QualType R = TInfo->getType(); 2124 2125 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2126 ForRedeclaration); 2127 2128 // See if this is a redefinition of a variable in the same scope. 2129 if (!D.getCXXScopeSpec().isSet()) { 2130 bool IsLinkageLookup = false; 2131 2132 // If the declaration we're planning to build will be a function 2133 // or object with linkage, then look for another declaration with 2134 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2135 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2136 /* Do nothing*/; 2137 else if (R->isFunctionType()) { 2138 if (CurContext->isFunctionOrMethod() || 2139 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2140 IsLinkageLookup = true; 2141 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2142 IsLinkageLookup = true; 2143 else if (CurContext->getLookupContext()->isTranslationUnit() && 2144 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2145 IsLinkageLookup = true; 2146 2147 if (IsLinkageLookup) 2148 Previous.clear(LookupRedeclarationWithLinkage); 2149 2150 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2151 } else { // Something like "int foo::x;" 2152 LookupQualifiedName(Previous, DC); 2153 2154 // Don't consider using declarations as previous declarations for 2155 // out-of-line members. 2156 RemoveUsingDecls(Previous); 2157 2158 // C++ 7.3.1.2p2: 2159 // Members (including explicit specializations of templates) of a named 2160 // namespace can also be defined outside that namespace by explicit 2161 // qualification of the name being defined, provided that the entity being 2162 // defined was already declared in the namespace and the definition appears 2163 // after the point of declaration in a namespace that encloses the 2164 // declarations namespace. 2165 // 2166 // Note that we only check the context at this point. We don't yet 2167 // have enough information to make sure that PrevDecl is actually 2168 // the declaration we want to match. For example, given: 2169 // 2170 // class X { 2171 // void f(); 2172 // void f(float); 2173 // }; 2174 // 2175 // void X::f(int) { } // ill-formed 2176 // 2177 // In this case, PrevDecl will point to the overload set 2178 // containing the two f's declared in X, but neither of them 2179 // matches. 2180 2181 // First check whether we named the global scope. 2182 if (isa<TranslationUnitDecl>(DC)) { 2183 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2184 << Name << D.getCXXScopeSpec().getRange(); 2185 } else { 2186 DeclContext *Cur = CurContext; 2187 while (isa<LinkageSpecDecl>(Cur)) 2188 Cur = Cur->getParent(); 2189 if (!Cur->Encloses(DC)) { 2190 // The qualifying scope doesn't enclose the original declaration. 2191 // Emit diagnostic based on current scope. 2192 SourceLocation L = D.getIdentifierLoc(); 2193 SourceRange R = D.getCXXScopeSpec().getRange(); 2194 if (isa<FunctionDecl>(Cur)) 2195 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2196 else 2197 Diag(L, diag::err_invalid_declarator_scope) 2198 << Name << cast<NamedDecl>(DC) << R; 2199 D.setInvalidType(); 2200 } 2201 } 2202 } 2203 2204 if (Previous.isSingleResult() && 2205 Previous.getFoundDecl()->isTemplateParameter()) { 2206 // Maybe we will complain about the shadowed template parameter. 2207 if (!D.isInvalidType()) 2208 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2209 Previous.getFoundDecl())) 2210 D.setInvalidType(); 2211 2212 // Just pretend that we didn't see the previous declaration. 2213 Previous.clear(); 2214 } 2215 2216 // In C++, the previous declaration we find might be a tag type 2217 // (class or enum). In this case, the new declaration will hide the 2218 // tag type. Note that this does does not apply if we're declaring a 2219 // typedef (C++ [dcl.typedef]p4). 2220 if (Previous.isSingleTagDecl() && 2221 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2222 Previous.clear(); 2223 2224 bool Redeclaration = false; 2225 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2226 if (TemplateParamLists.size()) { 2227 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2228 return DeclPtrTy(); 2229 } 2230 2231 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2232 } else if (R->isFunctionType()) { 2233 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2234 move(TemplateParamLists), 2235 IsFunctionDefinition, Redeclaration); 2236 } else { 2237 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2238 move(TemplateParamLists), 2239 Redeclaration); 2240 } 2241 2242 if (New == 0) 2243 return DeclPtrTy(); 2244 2245 // If this has an identifier and is not an invalid redeclaration or 2246 // function template specialization, add it to the scope stack. 2247 if (Name && !(Redeclaration && New->isInvalidDecl())) 2248 PushOnScopeChains(New, S); 2249 2250 return DeclPtrTy::make(New); 2251} 2252 2253/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2254/// types into constant array types in certain situations which would otherwise 2255/// be errors (for GCC compatibility). 2256static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2257 ASTContext &Context, 2258 bool &SizeIsNegative) { 2259 // This method tries to turn a variable array into a constant 2260 // array even when the size isn't an ICE. This is necessary 2261 // for compatibility with code that depends on gcc's buggy 2262 // constant expression folding, like struct {char x[(int)(char*)2];} 2263 SizeIsNegative = false; 2264 2265 QualifierCollector Qs; 2266 const Type *Ty = Qs.strip(T); 2267 2268 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2269 QualType Pointee = PTy->getPointeeType(); 2270 QualType FixedType = 2271 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2272 if (FixedType.isNull()) return FixedType; 2273 FixedType = Context.getPointerType(FixedType); 2274 return Qs.apply(FixedType); 2275 } 2276 2277 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2278 if (!VLATy) 2279 return QualType(); 2280 // FIXME: We should probably handle this case 2281 if (VLATy->getElementType()->isVariablyModifiedType()) 2282 return QualType(); 2283 2284 Expr::EvalResult EvalResult; 2285 if (!VLATy->getSizeExpr() || 2286 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2287 !EvalResult.Val.isInt()) 2288 return QualType(); 2289 2290 llvm::APSInt &Res = EvalResult.Val.getInt(); 2291 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2292 // TODO: preserve the size expression in declarator info 2293 return Context.getConstantArrayType(VLATy->getElementType(), 2294 Res, ArrayType::Normal, 0); 2295 } 2296 2297 SizeIsNegative = true; 2298 return QualType(); 2299} 2300 2301/// \brief Register the given locally-scoped external C declaration so 2302/// that it can be found later for redeclarations 2303void 2304Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2305 const LookupResult &Previous, 2306 Scope *S) { 2307 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2308 "Decl is not a locally-scoped decl!"); 2309 // Note that we have a locally-scoped external with this name. 2310 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2311 2312 if (!Previous.isSingleResult()) 2313 return; 2314 2315 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2316 2317 // If there was a previous declaration of this variable, it may be 2318 // in our identifier chain. Update the identifier chain with the new 2319 // declaration. 2320 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2321 // The previous declaration was found on the identifer resolver 2322 // chain, so remove it from its scope. 2323 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2324 S = S->getParent(); 2325 2326 if (S) 2327 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2328 } 2329} 2330 2331/// \brief Diagnose function specifiers on a declaration of an identifier that 2332/// does not identify a function. 2333void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2334 // FIXME: We should probably indicate the identifier in question to avoid 2335 // confusion for constructs like "inline int a(), b;" 2336 if (D.getDeclSpec().isInlineSpecified()) 2337 Diag(D.getDeclSpec().getInlineSpecLoc(), 2338 diag::err_inline_non_function); 2339 2340 if (D.getDeclSpec().isVirtualSpecified()) 2341 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2342 diag::err_virtual_non_function); 2343 2344 if (D.getDeclSpec().isExplicitSpecified()) 2345 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2346 diag::err_explicit_non_function); 2347} 2348 2349NamedDecl* 2350Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2351 QualType R, TypeSourceInfo *TInfo, 2352 LookupResult &Previous, bool &Redeclaration) { 2353 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2354 if (D.getCXXScopeSpec().isSet()) { 2355 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2356 << D.getCXXScopeSpec().getRange(); 2357 D.setInvalidType(); 2358 // Pretend we didn't see the scope specifier. 2359 DC = CurContext; 2360 Previous.clear(); 2361 } 2362 2363 if (getLangOptions().CPlusPlus) { 2364 // Check that there are no default arguments (C++ only). 2365 CheckExtraCXXDefaultArguments(D); 2366 } 2367 2368 DiagnoseFunctionSpecifiers(D); 2369 2370 if (D.getDeclSpec().isThreadSpecified()) 2371 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2372 2373 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2374 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2375 << D.getName().getSourceRange(); 2376 return 0; 2377 } 2378 2379 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2380 if (!NewTD) return 0; 2381 2382 // Handle attributes prior to checking for duplicates in MergeVarDecl 2383 ProcessDeclAttributes(S, NewTD, D); 2384 2385 // Merge the decl with the existing one if appropriate. If the decl is 2386 // in an outer scope, it isn't the same thing. 2387 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2388 if (!Previous.empty()) { 2389 Redeclaration = true; 2390 MergeTypeDefDecl(NewTD, Previous); 2391 } 2392 2393 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2394 // then it shall have block scope. 2395 QualType T = NewTD->getUnderlyingType(); 2396 if (T->isVariablyModifiedType()) { 2397 FunctionNeedsScopeChecking() = true; 2398 2399 if (S->getFnParent() == 0) { 2400 bool SizeIsNegative; 2401 QualType FixedTy = 2402 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2403 if (!FixedTy.isNull()) { 2404 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2405 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2406 } else { 2407 if (SizeIsNegative) 2408 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2409 else if (T->isVariableArrayType()) 2410 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2411 else 2412 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2413 NewTD->setInvalidDecl(); 2414 } 2415 } 2416 } 2417 2418 // If this is the C FILE type, notify the AST context. 2419 if (IdentifierInfo *II = NewTD->getIdentifier()) 2420 if (!NewTD->isInvalidDecl() && 2421 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2422 if (II->isStr("FILE")) 2423 Context.setFILEDecl(NewTD); 2424 else if (II->isStr("jmp_buf")) 2425 Context.setjmp_bufDecl(NewTD); 2426 else if (II->isStr("sigjmp_buf")) 2427 Context.setsigjmp_bufDecl(NewTD); 2428 } 2429 2430 return NewTD; 2431} 2432 2433/// \brief Determines whether the given declaration is an out-of-scope 2434/// previous declaration. 2435/// 2436/// This routine should be invoked when name lookup has found a 2437/// previous declaration (PrevDecl) that is not in the scope where a 2438/// new declaration by the same name is being introduced. If the new 2439/// declaration occurs in a local scope, previous declarations with 2440/// linkage may still be considered previous declarations (C99 2441/// 6.2.2p4-5, C++ [basic.link]p6). 2442/// 2443/// \param PrevDecl the previous declaration found by name 2444/// lookup 2445/// 2446/// \param DC the context in which the new declaration is being 2447/// declared. 2448/// 2449/// \returns true if PrevDecl is an out-of-scope previous declaration 2450/// for a new delcaration with the same name. 2451static bool 2452isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2453 ASTContext &Context) { 2454 if (!PrevDecl) 2455 return 0; 2456 2457 if (!PrevDecl->hasLinkage()) 2458 return false; 2459 2460 if (Context.getLangOptions().CPlusPlus) { 2461 // C++ [basic.link]p6: 2462 // If there is a visible declaration of an entity with linkage 2463 // having the same name and type, ignoring entities declared 2464 // outside the innermost enclosing namespace scope, the block 2465 // scope declaration declares that same entity and receives the 2466 // linkage of the previous declaration. 2467 DeclContext *OuterContext = DC->getLookupContext(); 2468 if (!OuterContext->isFunctionOrMethod()) 2469 // This rule only applies to block-scope declarations. 2470 return false; 2471 else { 2472 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2473 if (PrevOuterContext->isRecord()) 2474 // We found a member function: ignore it. 2475 return false; 2476 else { 2477 // Find the innermost enclosing namespace for the new and 2478 // previous declarations. 2479 while (!OuterContext->isFileContext()) 2480 OuterContext = OuterContext->getParent(); 2481 while (!PrevOuterContext->isFileContext()) 2482 PrevOuterContext = PrevOuterContext->getParent(); 2483 2484 // The previous declaration is in a different namespace, so it 2485 // isn't the same function. 2486 if (OuterContext->getPrimaryContext() != 2487 PrevOuterContext->getPrimaryContext()) 2488 return false; 2489 } 2490 } 2491 } 2492 2493 return true; 2494} 2495 2496static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2497 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2498 if (!SS.isSet()) return; 2499 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2500 SS.getRange()); 2501} 2502 2503NamedDecl* 2504Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2505 QualType R, TypeSourceInfo *TInfo, 2506 LookupResult &Previous, 2507 MultiTemplateParamsArg TemplateParamLists, 2508 bool &Redeclaration) { 2509 DeclarationName Name = GetNameForDeclarator(D); 2510 2511 // Check that there are no default arguments (C++ only). 2512 if (getLangOptions().CPlusPlus) 2513 CheckExtraCXXDefaultArguments(D); 2514 2515 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2516 assert(SCSpec != DeclSpec::SCS_typedef && 2517 "Parser allowed 'typedef' as storage class VarDecl."); 2518 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 2519 if (SCSpec == DeclSpec::SCS_mutable) { 2520 // mutable can only appear on non-static class members, so it's always 2521 // an error here 2522 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2523 D.setInvalidType(); 2524 SC = VarDecl::None; 2525 } 2526 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2527 VarDecl::StorageClass SCAsWritten 2528 = StorageClassSpecToVarDeclStorageClass(SCSpec, DC); 2529 2530 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2531 if (!II) { 2532 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2533 << Name.getAsString(); 2534 return 0; 2535 } 2536 2537 DiagnoseFunctionSpecifiers(D); 2538 2539 if (!DC->isRecord() && S->getFnParent() == 0) { 2540 // C99 6.9p2: The storage-class specifiers auto and register shall not 2541 // appear in the declaration specifiers in an external declaration. 2542 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2543 2544 // If this is a register variable with an asm label specified, then this 2545 // is a GNU extension. 2546 if (SC == VarDecl::Register && D.getAsmLabel()) 2547 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2548 else 2549 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2550 D.setInvalidType(); 2551 } 2552 } 2553 if (DC->isRecord() && !CurContext->isRecord()) { 2554 // This is an out-of-line definition of a static data member. 2555 if (SC == VarDecl::Static) { 2556 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2557 diag::err_static_out_of_line) 2558 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2559 } else if (SC == VarDecl::None) 2560 SC = VarDecl::Static; 2561 } 2562 if (SC == VarDecl::Static) { 2563 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2564 if (RD->isLocalClass()) 2565 Diag(D.getIdentifierLoc(), 2566 diag::err_static_data_member_not_allowed_in_local_class) 2567 << Name << RD->getDeclName(); 2568 } 2569 } 2570 2571 // Match up the template parameter lists with the scope specifier, then 2572 // determine whether we have a template or a template specialization. 2573 bool isExplicitSpecialization = false; 2574 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2575 if (TemplateParameterList *TemplateParams 2576 = MatchTemplateParametersToScopeSpecifier( 2577 D.getDeclSpec().getSourceRange().getBegin(), 2578 D.getCXXScopeSpec(), 2579 (TemplateParameterList**)TemplateParamLists.get(), 2580 TemplateParamLists.size(), 2581 /*never a friend*/ false, 2582 isExplicitSpecialization)) { 2583 // All but one template parameter lists have been matching. 2584 --NumMatchedTemplateParamLists; 2585 2586 if (TemplateParams->size() > 0) { 2587 // There is no such thing as a variable template. 2588 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2589 << II 2590 << SourceRange(TemplateParams->getTemplateLoc(), 2591 TemplateParams->getRAngleLoc()); 2592 return 0; 2593 } else { 2594 // There is an extraneous 'template<>' for this variable. Complain 2595 // about it, but allow the declaration of the variable. 2596 Diag(TemplateParams->getTemplateLoc(), 2597 diag::err_template_variable_noparams) 2598 << II 2599 << SourceRange(TemplateParams->getTemplateLoc(), 2600 TemplateParams->getRAngleLoc()); 2601 2602 isExplicitSpecialization = true; 2603 } 2604 } 2605 2606 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2607 II, R, TInfo, SC, SCAsWritten); 2608 2609 if (D.isInvalidType()) 2610 NewVD->setInvalidDecl(); 2611 2612 SetNestedNameSpecifier(NewVD, D); 2613 2614 if (NumMatchedTemplateParamLists > 0) { 2615 NewVD->setTemplateParameterListsInfo(Context, 2616 NumMatchedTemplateParamLists, 2617 (TemplateParameterList**)TemplateParamLists.release()); 2618 } 2619 2620 if (D.getDeclSpec().isThreadSpecified()) { 2621 if (NewVD->hasLocalStorage()) 2622 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2623 else if (!Context.Target.isTLSSupported()) 2624 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2625 else 2626 NewVD->setThreadSpecified(true); 2627 } 2628 2629 // Set the lexical context. If the declarator has a C++ scope specifier, the 2630 // lexical context will be different from the semantic context. 2631 NewVD->setLexicalDeclContext(CurContext); 2632 2633 // Handle attributes prior to checking for duplicates in MergeVarDecl 2634 ProcessDeclAttributes(S, NewVD, D); 2635 2636 // Handle GNU asm-label extension (encoded as an attribute). 2637 if (Expr *E = (Expr*) D.getAsmLabel()) { 2638 // The parser guarantees this is a string. 2639 StringLiteral *SE = cast<StringLiteral>(E); 2640 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2641 } 2642 2643 // Diagnose shadowed variables before filtering for scope. 2644 if (!D.getCXXScopeSpec().isSet()) 2645 CheckShadow(S, NewVD, Previous); 2646 2647 // Don't consider existing declarations that are in a different 2648 // scope and are out-of-semantic-context declarations (if the new 2649 // declaration has linkage). 2650 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2651 2652 // Merge the decl with the existing one if appropriate. 2653 if (!Previous.empty()) { 2654 if (Previous.isSingleResult() && 2655 isa<FieldDecl>(Previous.getFoundDecl()) && 2656 D.getCXXScopeSpec().isSet()) { 2657 // The user tried to define a non-static data member 2658 // out-of-line (C++ [dcl.meaning]p1). 2659 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2660 << D.getCXXScopeSpec().getRange(); 2661 Previous.clear(); 2662 NewVD->setInvalidDecl(); 2663 } 2664 } else if (D.getCXXScopeSpec().isSet()) { 2665 // No previous declaration in the qualifying scope. 2666 Diag(D.getIdentifierLoc(), diag::err_no_member) 2667 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2668 << D.getCXXScopeSpec().getRange(); 2669 NewVD->setInvalidDecl(); 2670 } 2671 2672 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2673 2674 // This is an explicit specialization of a static data member. Check it. 2675 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2676 CheckMemberSpecialization(NewVD, Previous)) 2677 NewVD->setInvalidDecl(); 2678 2679 // attributes declared post-definition are currently ignored 2680 if (Previous.isSingleResult()) { 2681 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2682 if (Def && (Def = Def->getDefinition()) && 2683 Def != NewVD && D.hasAttributes()) { 2684 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2685 Diag(Def->getLocation(), diag::note_previous_definition); 2686 } 2687 } 2688 2689 // If this is a locally-scoped extern C variable, update the map of 2690 // such variables. 2691 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2692 !NewVD->isInvalidDecl()) 2693 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2694 2695 return NewVD; 2696} 2697 2698/// \brief Diagnose variable or built-in function shadowing. Implements 2699/// -Wshadow. 2700/// 2701/// This method is called whenever a VarDecl is added to a "useful" 2702/// scope. 2703/// 2704/// \param S the scope in which the shadowing name is being declared 2705/// \param R the lookup of the name 2706/// 2707void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2708 // Return if warning is ignored. 2709 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2710 return; 2711 2712 // Don't diagnose declarations at file scope. The scope might not 2713 // have a DeclContext if (e.g.) we're parsing a function prototype. 2714 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2715 if (NewDC && NewDC->isFileContext()) 2716 return; 2717 2718 // Only diagnose if we're shadowing an unambiguous field or variable. 2719 if (R.getResultKind() != LookupResult::Found) 2720 return; 2721 2722 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2723 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2724 return; 2725 2726 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2727 2728 // Only warn about certain kinds of shadowing for class members. 2729 if (NewDC && NewDC->isRecord()) { 2730 // In particular, don't warn about shadowing non-class members. 2731 if (!OldDC->isRecord()) 2732 return; 2733 2734 // TODO: should we warn about static data members shadowing 2735 // static data members from base classes? 2736 2737 // TODO: don't diagnose for inaccessible shadowed members. 2738 // This is hard to do perfectly because we might friend the 2739 // shadowing context, but that's just a false negative. 2740 } 2741 2742 // Determine what kind of declaration we're shadowing. 2743 unsigned Kind; 2744 if (isa<RecordDecl>(OldDC)) { 2745 if (isa<FieldDecl>(ShadowedDecl)) 2746 Kind = 3; // field 2747 else 2748 Kind = 2; // static data member 2749 } else if (OldDC->isFileContext()) 2750 Kind = 1; // global 2751 else 2752 Kind = 0; // local 2753 2754 DeclarationName Name = R.getLookupName(); 2755 2756 // Emit warning and note. 2757 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2758 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2759} 2760 2761/// \brief Check -Wshadow without the advantage of a previous lookup. 2762void Sema::CheckShadow(Scope *S, VarDecl *D) { 2763 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2764 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2765 LookupName(R, S); 2766 CheckShadow(S, D, R); 2767} 2768 2769/// \brief Perform semantic checking on a newly-created variable 2770/// declaration. 2771/// 2772/// This routine performs all of the type-checking required for a 2773/// variable declaration once it has been built. It is used both to 2774/// check variables after they have been parsed and their declarators 2775/// have been translated into a declaration, and to check variables 2776/// that have been instantiated from a template. 2777/// 2778/// Sets NewVD->isInvalidDecl() if an error was encountered. 2779void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2780 LookupResult &Previous, 2781 bool &Redeclaration) { 2782 // If the decl is already known invalid, don't check it. 2783 if (NewVD->isInvalidDecl()) 2784 return; 2785 2786 QualType T = NewVD->getType(); 2787 2788 if (T->isObjCObjectType()) { 2789 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2790 return NewVD->setInvalidDecl(); 2791 } 2792 2793 // Emit an error if an address space was applied to decl with local storage. 2794 // This includes arrays of objects with address space qualifiers, but not 2795 // automatic variables that point to other address spaces. 2796 // ISO/IEC TR 18037 S5.1.2 2797 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2798 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2799 return NewVD->setInvalidDecl(); 2800 } 2801 2802 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2803 && !NewVD->hasAttr<BlocksAttr>()) 2804 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2805 2806 bool isVM = T->isVariablyModifiedType(); 2807 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2808 NewVD->hasAttr<BlocksAttr>() || 2809 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2810 // However, this turns on the scope checker for everything with a variable 2811 // which may impact compile time. See if we can find a better solution 2812 // to this, perhaps only checking functions that contain gotos in C++? 2813 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2814 FunctionNeedsScopeChecking() = true; 2815 2816 if ((isVM && NewVD->hasLinkage()) || 2817 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2818 bool SizeIsNegative; 2819 QualType FixedTy = 2820 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2821 2822 if (FixedTy.isNull() && T->isVariableArrayType()) { 2823 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2824 // FIXME: This won't give the correct result for 2825 // int a[10][n]; 2826 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2827 2828 if (NewVD->isFileVarDecl()) 2829 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2830 << SizeRange; 2831 else if (NewVD->getStorageClass() == VarDecl::Static) 2832 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2833 << SizeRange; 2834 else 2835 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2836 << SizeRange; 2837 return NewVD->setInvalidDecl(); 2838 } 2839 2840 if (FixedTy.isNull()) { 2841 if (NewVD->isFileVarDecl()) 2842 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2843 else 2844 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2845 return NewVD->setInvalidDecl(); 2846 } 2847 2848 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2849 NewVD->setType(FixedTy); 2850 } 2851 2852 if (Previous.empty() && NewVD->isExternC()) { 2853 // Since we did not find anything by this name and we're declaring 2854 // an extern "C" variable, look for a non-visible extern "C" 2855 // declaration with the same name. 2856 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2857 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2858 if (Pos != LocallyScopedExternalDecls.end()) 2859 Previous.addDecl(Pos->second); 2860 } 2861 2862 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2863 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2864 << T; 2865 return NewVD->setInvalidDecl(); 2866 } 2867 2868 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2869 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2870 return NewVD->setInvalidDecl(); 2871 } 2872 2873 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2874 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2875 return NewVD->setInvalidDecl(); 2876 } 2877 2878 // Function pointers and references cannot have qualified function type, only 2879 // function pointer-to-members can do that. 2880 QualType Pointee; 2881 unsigned PtrOrRef = 0; 2882 if (const PointerType *Ptr = T->getAs<PointerType>()) 2883 Pointee = Ptr->getPointeeType(); 2884 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 2885 Pointee = Ref->getPointeeType(); 2886 PtrOrRef = 1; 2887 } 2888 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 2889 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 2890 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 2891 << PtrOrRef; 2892 return NewVD->setInvalidDecl(); 2893 } 2894 2895 if (!Previous.empty()) { 2896 Redeclaration = true; 2897 MergeVarDecl(NewVD, Previous); 2898 } 2899} 2900 2901/// \brief Data used with FindOverriddenMethod 2902struct FindOverriddenMethodData { 2903 Sema *S; 2904 CXXMethodDecl *Method; 2905}; 2906 2907/// \brief Member lookup function that determines whether a given C++ 2908/// method overrides a method in a base class, to be used with 2909/// CXXRecordDecl::lookupInBases(). 2910static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2911 CXXBasePath &Path, 2912 void *UserData) { 2913 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2914 2915 FindOverriddenMethodData *Data 2916 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2917 2918 DeclarationName Name = Data->Method->getDeclName(); 2919 2920 // FIXME: Do we care about other names here too? 2921 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2922 // We really want to find the base class destructor here. 2923 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2924 CanQualType CT = Data->S->Context.getCanonicalType(T); 2925 2926 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2927 } 2928 2929 for (Path.Decls = BaseRecord->lookup(Name); 2930 Path.Decls.first != Path.Decls.second; 2931 ++Path.Decls.first) { 2932 NamedDecl *D = *Path.Decls.first; 2933 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 2934 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 2935 return true; 2936 } 2937 } 2938 2939 return false; 2940} 2941 2942/// AddOverriddenMethods - See if a method overrides any in the base classes, 2943/// and if so, check that it's a valid override and remember it. 2944void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2945 // Look for virtual methods in base classes that this method might override. 2946 CXXBasePaths Paths; 2947 FindOverriddenMethodData Data; 2948 Data.Method = MD; 2949 Data.S = this; 2950 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2951 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2952 E = Paths.found_decls_end(); I != E; ++I) { 2953 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2954 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2955 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2956 !CheckOverridingFunctionAttributes(MD, OldMD)) 2957 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2958 } 2959 } 2960 } 2961} 2962 2963NamedDecl* 2964Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2965 QualType R, TypeSourceInfo *TInfo, 2966 LookupResult &Previous, 2967 MultiTemplateParamsArg TemplateParamLists, 2968 bool IsFunctionDefinition, bool &Redeclaration) { 2969 assert(R.getTypePtr()->isFunctionType()); 2970 2971 DeclarationName Name = GetNameForDeclarator(D); 2972 FunctionDecl::StorageClass SC = FunctionDecl::None; 2973 switch (D.getDeclSpec().getStorageClassSpec()) { 2974 default: assert(0 && "Unknown storage class!"); 2975 case DeclSpec::SCS_auto: 2976 case DeclSpec::SCS_register: 2977 case DeclSpec::SCS_mutable: 2978 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2979 diag::err_typecheck_sclass_func); 2980 D.setInvalidType(); 2981 break; 2982 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2983 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2984 case DeclSpec::SCS_static: { 2985 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2986 // C99 6.7.1p5: 2987 // The declaration of an identifier for a function that has 2988 // block scope shall have no explicit storage-class specifier 2989 // other than extern 2990 // See also (C++ [dcl.stc]p4). 2991 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2992 diag::err_static_block_func); 2993 SC = FunctionDecl::None; 2994 } else 2995 SC = FunctionDecl::Static; 2996 break; 2997 } 2998 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2999 } 3000 3001 if (D.getDeclSpec().isThreadSpecified()) 3002 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3003 3004 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3005 bool isInline = D.getDeclSpec().isInlineSpecified(); 3006 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3007 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3008 3009 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3010 FunctionDecl::StorageClass SCAsWritten 3011 = StorageClassSpecToFunctionDeclStorageClass(SCSpec, DC); 3012 3013 // Check that the return type is not an abstract class type. 3014 // For record types, this is done by the AbstractClassUsageDiagnoser once 3015 // the class has been completely parsed. 3016 if (!DC->isRecord() && 3017 RequireNonAbstractType(D.getIdentifierLoc(), 3018 R->getAs<FunctionType>()->getResultType(), 3019 diag::err_abstract_type_in_decl, 3020 AbstractReturnType)) 3021 D.setInvalidType(); 3022 3023 // Do not allow returning a objc interface by-value. 3024 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3025 Diag(D.getIdentifierLoc(), 3026 diag::err_object_cannot_be_passed_returned_by_value) << 0 3027 << R->getAs<FunctionType>()->getResultType(); 3028 D.setInvalidType(); 3029 } 3030 3031 bool isVirtualOkay = false; 3032 FunctionDecl *NewFD; 3033 3034 if (isFriend) { 3035 // C++ [class.friend]p5 3036 // A function can be defined in a friend declaration of a 3037 // class . . . . Such a function is implicitly inline. 3038 isInline |= IsFunctionDefinition; 3039 } 3040 3041 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3042 // This is a C++ constructor declaration. 3043 assert(DC->isRecord() && 3044 "Constructors can only be declared in a member context"); 3045 3046 R = CheckConstructorDeclarator(D, R, SC); 3047 3048 // Create the new declaration 3049 NewFD = CXXConstructorDecl::Create(Context, 3050 cast<CXXRecordDecl>(DC), 3051 D.getIdentifierLoc(), Name, R, TInfo, 3052 isExplicit, isInline, 3053 /*isImplicitlyDeclared=*/false); 3054 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3055 // This is a C++ destructor declaration. 3056 if (DC->isRecord()) { 3057 R = CheckDestructorDeclarator(D, R, SC); 3058 3059 NewFD = CXXDestructorDecl::Create(Context, 3060 cast<CXXRecordDecl>(DC), 3061 D.getIdentifierLoc(), Name, R, 3062 isInline, 3063 /*isImplicitlyDeclared=*/false); 3064 NewFD->setTypeSourceInfo(TInfo); 3065 3066 isVirtualOkay = true; 3067 } else { 3068 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3069 3070 // Create a FunctionDecl to satisfy the function definition parsing 3071 // code path. 3072 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3073 Name, R, TInfo, SC, SCAsWritten, isInline, 3074 /*hasPrototype=*/true); 3075 D.setInvalidType(); 3076 } 3077 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3078 if (!DC->isRecord()) { 3079 Diag(D.getIdentifierLoc(), 3080 diag::err_conv_function_not_member); 3081 return 0; 3082 } 3083 3084 CheckConversionDeclarator(D, R, SC); 3085 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3086 D.getIdentifierLoc(), Name, R, TInfo, 3087 isInline, isExplicit); 3088 3089 isVirtualOkay = true; 3090 } else if (DC->isRecord()) { 3091 // If the of the function is the same as the name of the record, then this 3092 // must be an invalid constructor that has a return type. 3093 // (The parser checks for a return type and makes the declarator a 3094 // constructor if it has no return type). 3095 // must have an invalid constructor that has a return type 3096 if (Name.getAsIdentifierInfo() && 3097 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3098 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3099 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3100 << SourceRange(D.getIdentifierLoc()); 3101 return 0; 3102 } 3103 3104 bool isStatic = SC == FunctionDecl::Static; 3105 3106 // [class.free]p1: 3107 // Any allocation function for a class T is a static member 3108 // (even if not explicitly declared static). 3109 if (Name.getCXXOverloadedOperator() == OO_New || 3110 Name.getCXXOverloadedOperator() == OO_Array_New) 3111 isStatic = true; 3112 3113 // [class.free]p6 Any deallocation function for a class X is a static member 3114 // (even if not explicitly declared static). 3115 if (Name.getCXXOverloadedOperator() == OO_Delete || 3116 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3117 isStatic = true; 3118 3119 // This is a C++ method declaration. 3120 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3121 D.getIdentifierLoc(), Name, R, TInfo, 3122 isStatic, SCAsWritten, isInline); 3123 3124 isVirtualOkay = !isStatic; 3125 } else { 3126 // Determine whether the function was written with a 3127 // prototype. This true when: 3128 // - we're in C++ (where every function has a prototype), 3129 // - there is a prototype in the declarator, or 3130 // - the type R of the function is some kind of typedef or other reference 3131 // to a type name (which eventually refers to a function type). 3132 bool HasPrototype = 3133 getLangOptions().CPlusPlus || 3134 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3135 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3136 3137 NewFD = FunctionDecl::Create(Context, DC, 3138 D.getIdentifierLoc(), 3139 Name, R, TInfo, SC, SCAsWritten, isInline, 3140 HasPrototype); 3141 } 3142 3143 if (D.isInvalidType()) 3144 NewFD->setInvalidDecl(); 3145 3146 SetNestedNameSpecifier(NewFD, D); 3147 3148 // Set the lexical context. If the declarator has a C++ 3149 // scope specifier, or is the object of a friend declaration, the 3150 // lexical context will be different from the semantic context. 3151 NewFD->setLexicalDeclContext(CurContext); 3152 3153 // Match up the template parameter lists with the scope specifier, then 3154 // determine whether we have a template or a template specialization. 3155 FunctionTemplateDecl *FunctionTemplate = 0; 3156 bool isExplicitSpecialization = false; 3157 bool isFunctionTemplateSpecialization = false; 3158 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3159 if (TemplateParameterList *TemplateParams 3160 = MatchTemplateParametersToScopeSpecifier( 3161 D.getDeclSpec().getSourceRange().getBegin(), 3162 D.getCXXScopeSpec(), 3163 (TemplateParameterList**)TemplateParamLists.get(), 3164 TemplateParamLists.size(), 3165 isFriend, 3166 isExplicitSpecialization)) { 3167 // All but one template parameter lists have been matching. 3168 --NumMatchedTemplateParamLists; 3169 3170 if (TemplateParams->size() > 0) { 3171 // This is a function template 3172 3173 // Check that we can declare a template here. 3174 if (CheckTemplateDeclScope(S, TemplateParams)) 3175 return 0; 3176 3177 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3178 NewFD->getLocation(), 3179 Name, TemplateParams, 3180 NewFD); 3181 FunctionTemplate->setLexicalDeclContext(CurContext); 3182 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3183 } else { 3184 // This is a function template specialization. 3185 isFunctionTemplateSpecialization = true; 3186 3187 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3188 if (isFriend && isFunctionTemplateSpecialization) { 3189 // We want to remove the "template<>", found here. 3190 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3191 3192 // If we remove the template<> and the name is not a 3193 // template-id, we're actually silently creating a problem: 3194 // the friend declaration will refer to an untemplated decl, 3195 // and clearly the user wants a template specialization. So 3196 // we need to insert '<>' after the name. 3197 SourceLocation InsertLoc; 3198 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3199 InsertLoc = D.getName().getSourceRange().getEnd(); 3200 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3201 } 3202 3203 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3204 << Name << RemoveRange 3205 << FixItHint::CreateRemoval(RemoveRange) 3206 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3207 } 3208 } 3209 } 3210 3211 if (NumMatchedTemplateParamLists > 0) { 3212 NewFD->setTemplateParameterListsInfo(Context, 3213 NumMatchedTemplateParamLists, 3214 (TemplateParameterList**)TemplateParamLists.release()); 3215 } 3216 3217 // C++ [dcl.fct.spec]p5: 3218 // The virtual specifier shall only be used in declarations of 3219 // nonstatic class member functions that appear within a 3220 // member-specification of a class declaration; see 10.3. 3221 // 3222 if (isVirtual && !NewFD->isInvalidDecl()) { 3223 if (!isVirtualOkay) { 3224 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3225 diag::err_virtual_non_function); 3226 } else if (!CurContext->isRecord()) { 3227 // 'virtual' was specified outside of the class. 3228 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3229 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3230 } else { 3231 // Okay: Add virtual to the method. 3232 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3233 CurClass->setMethodAsVirtual(NewFD); 3234 } 3235 } 3236 3237 // C++ [dcl.fct.spec]p6: 3238 // The explicit specifier shall be used only in the declaration of a 3239 // constructor or conversion function within its class definition; see 12.3.1 3240 // and 12.3.2. 3241 if (isExplicit && !NewFD->isInvalidDecl()) { 3242 if (!CurContext->isRecord()) { 3243 // 'explicit' was specified outside of the class. 3244 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3245 diag::err_explicit_out_of_class) 3246 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3247 } else if (!isa<CXXConstructorDecl>(NewFD) && 3248 !isa<CXXConversionDecl>(NewFD)) { 3249 // 'explicit' was specified on a function that wasn't a constructor 3250 // or conversion function. 3251 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3252 diag::err_explicit_non_ctor_or_conv_function) 3253 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3254 } 3255 } 3256 3257 // Filter out previous declarations that don't match the scope. 3258 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3259 3260 if (isFriend) { 3261 // DC is the namespace in which the function is being declared. 3262 assert((DC->isFileContext() || !Previous.empty()) && 3263 "previously-undeclared friend function being created " 3264 "in a non-namespace context"); 3265 3266 // For now, claim that the objects have no previous declaration. 3267 if (FunctionTemplate) { 3268 FunctionTemplate->setObjectOfFriendDecl(false); 3269 FunctionTemplate->setAccess(AS_public); 3270 } 3271 NewFD->setObjectOfFriendDecl(false); 3272 NewFD->setAccess(AS_public); 3273 } 3274 3275 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3276 !CurContext->isRecord()) { 3277 // C++ [class.static]p1: 3278 // A data or function member of a class may be declared static 3279 // in a class definition, in which case it is a static member of 3280 // the class. 3281 3282 // Complain about the 'static' specifier if it's on an out-of-line 3283 // member function definition. 3284 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3285 diag::err_static_out_of_line) 3286 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3287 } 3288 3289 // Handle GNU asm-label extension (encoded as an attribute). 3290 if (Expr *E = (Expr*) D.getAsmLabel()) { 3291 // The parser guarantees this is a string. 3292 StringLiteral *SE = cast<StringLiteral>(E); 3293 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3294 } 3295 3296 // Copy the parameter declarations from the declarator D to the function 3297 // declaration NewFD, if they are available. First scavenge them into Params. 3298 llvm::SmallVector<ParmVarDecl*, 16> Params; 3299 if (D.getNumTypeObjects() > 0) { 3300 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3301 3302 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3303 // function that takes no arguments, not a function that takes a 3304 // single void argument. 3305 // We let through "const void" here because Sema::GetTypeForDeclarator 3306 // already checks for that case. 3307 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3308 FTI.ArgInfo[0].Param && 3309 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3310 // Empty arg list, don't push any params. 3311 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3312 3313 // In C++, the empty parameter-type-list must be spelled "void"; a 3314 // typedef of void is not permitted. 3315 if (getLangOptions().CPlusPlus && 3316 Param->getType().getUnqualifiedType() != Context.VoidTy) 3317 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3318 // FIXME: Leaks decl? 3319 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3320 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3321 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3322 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3323 Param->setDeclContext(NewFD); 3324 Params.push_back(Param); 3325 3326 if (Param->isInvalidDecl()) 3327 NewFD->setInvalidDecl(); 3328 } 3329 } 3330 3331 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3332 // When we're declaring a function with a typedef, typeof, etc as in the 3333 // following example, we'll need to synthesize (unnamed) 3334 // parameters for use in the declaration. 3335 // 3336 // @code 3337 // typedef void fn(int); 3338 // fn f; 3339 // @endcode 3340 3341 // Synthesize a parameter for each argument type. 3342 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3343 AE = FT->arg_type_end(); AI != AE; ++AI) { 3344 ParmVarDecl *Param = 3345 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3346 Params.push_back(Param); 3347 } 3348 } else { 3349 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3350 "Should not need args for typedef of non-prototype fn"); 3351 } 3352 // Finally, we know we have the right number of parameters, install them. 3353 NewFD->setParams(Params.data(), Params.size()); 3354 3355 // If the declarator is a template-id, translate the parser's template 3356 // argument list into our AST format. 3357 bool HasExplicitTemplateArgs = false; 3358 TemplateArgumentListInfo TemplateArgs; 3359 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3360 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3361 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3362 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3363 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3364 TemplateId->getTemplateArgs(), 3365 TemplateId->NumArgs); 3366 translateTemplateArguments(TemplateArgsPtr, 3367 TemplateArgs); 3368 TemplateArgsPtr.release(); 3369 3370 HasExplicitTemplateArgs = true; 3371 3372 if (FunctionTemplate) { 3373 // FIXME: Diagnose function template with explicit template 3374 // arguments. 3375 HasExplicitTemplateArgs = false; 3376 } else if (!isFunctionTemplateSpecialization && 3377 !D.getDeclSpec().isFriendSpecified()) { 3378 // We have encountered something that the user meant to be a 3379 // specialization (because it has explicitly-specified template 3380 // arguments) but that was not introduced with a "template<>" (or had 3381 // too few of them). 3382 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3383 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3384 << FixItHint::CreateInsertion( 3385 D.getDeclSpec().getSourceRange().getBegin(), 3386 "template<> "); 3387 isFunctionTemplateSpecialization = true; 3388 } else { 3389 // "friend void foo<>(int);" is an implicit specialization decl. 3390 isFunctionTemplateSpecialization = true; 3391 } 3392 } else if (isFriend && isFunctionTemplateSpecialization) { 3393 // This combination is only possible in a recovery case; the user 3394 // wrote something like: 3395 // template <> friend void foo(int); 3396 // which we're recovering from as if the user had written: 3397 // friend void foo<>(int); 3398 // Go ahead and fake up a template id. 3399 HasExplicitTemplateArgs = true; 3400 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3401 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3402 } 3403 3404 // If it's a friend (and only if it's a friend), it's possible 3405 // that either the specialized function type or the specialized 3406 // template is dependent, and therefore matching will fail. In 3407 // this case, don't check the specialization yet. 3408 if (isFunctionTemplateSpecialization && isFriend && 3409 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3410 assert(HasExplicitTemplateArgs && 3411 "friend function specialization without template args"); 3412 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3413 Previous)) 3414 NewFD->setInvalidDecl(); 3415 } else if (isFunctionTemplateSpecialization) { 3416 if (CheckFunctionTemplateSpecialization(NewFD, 3417 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3418 Previous)) 3419 NewFD->setInvalidDecl(); 3420 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3421 if (CheckMemberSpecialization(NewFD, Previous)) 3422 NewFD->setInvalidDecl(); 3423 } 3424 3425 // Perform semantic checking on the function declaration. 3426 bool OverloadableAttrRequired = false; // FIXME: HACK! 3427 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3428 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3429 3430 assert((NewFD->isInvalidDecl() || !Redeclaration || 3431 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3432 "previous declaration set still overloaded"); 3433 3434 NamedDecl *PrincipalDecl = (FunctionTemplate 3435 ? cast<NamedDecl>(FunctionTemplate) 3436 : NewFD); 3437 3438 if (isFriend && Redeclaration) { 3439 AccessSpecifier Access = AS_public; 3440 if (!NewFD->isInvalidDecl()) 3441 Access = NewFD->getPreviousDeclaration()->getAccess(); 3442 3443 NewFD->setAccess(Access); 3444 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3445 3446 PrincipalDecl->setObjectOfFriendDecl(true); 3447 } 3448 3449 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3450 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3451 PrincipalDecl->setNonMemberOperator(); 3452 3453 // If we have a function template, check the template parameter 3454 // list. This will check and merge default template arguments. 3455 if (FunctionTemplate) { 3456 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3457 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3458 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3459 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3460 : TPC_FunctionTemplate); 3461 } 3462 3463 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3464 // Fake up an access specifier if it's supposed to be a class member. 3465 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3466 NewFD->setAccess(AS_public); 3467 3468 // An out-of-line member function declaration must also be a 3469 // definition (C++ [dcl.meaning]p1). 3470 // Note that this is not the case for explicit specializations of 3471 // function templates or member functions of class templates, per 3472 // C++ [temp.expl.spec]p2. 3473 if (!IsFunctionDefinition && !isFriend && 3474 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3475 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3476 << D.getCXXScopeSpec().getRange(); 3477 NewFD->setInvalidDecl(); 3478 } else if (!Redeclaration && 3479 !(isFriend && CurContext->isDependentContext())) { 3480 // The user tried to provide an out-of-line definition for a 3481 // function that is a member of a class or namespace, but there 3482 // was no such member function declared (C++ [class.mfct]p2, 3483 // C++ [namespace.memdef]p2). For example: 3484 // 3485 // class X { 3486 // void f() const; 3487 // }; 3488 // 3489 // void X::f() { } // ill-formed 3490 // 3491 // Complain about this problem, and attempt to suggest close 3492 // matches (e.g., those that differ only in cv-qualifiers and 3493 // whether the parameter types are references). 3494 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3495 << Name << DC << D.getCXXScopeSpec().getRange(); 3496 NewFD->setInvalidDecl(); 3497 3498 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3499 ForRedeclaration); 3500 LookupQualifiedName(Prev, DC); 3501 assert(!Prev.isAmbiguous() && 3502 "Cannot have an ambiguity in previous-declaration lookup"); 3503 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3504 Func != FuncEnd; ++Func) { 3505 if (isa<FunctionDecl>(*Func) && 3506 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3507 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3508 } 3509 } 3510 } 3511 3512 // Handle attributes. We need to have merged decls when handling attributes 3513 // (for example to check for conflicts, etc). 3514 // FIXME: This needs to happen before we merge declarations. Then, 3515 // let attribute merging cope with attribute conflicts. 3516 ProcessDeclAttributes(S, NewFD, D); 3517 3518 // attributes declared post-definition are currently ignored 3519 if (Redeclaration && Previous.isSingleResult()) { 3520 const FunctionDecl *Def; 3521 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3522 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3523 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3524 Diag(Def->getLocation(), diag::note_previous_definition); 3525 } 3526 } 3527 3528 AddKnownFunctionAttributes(NewFD); 3529 3530 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3531 // If a function name is overloadable in C, then every function 3532 // with that name must be marked "overloadable". 3533 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3534 << Redeclaration << NewFD; 3535 if (!Previous.empty()) 3536 Diag(Previous.getRepresentativeDecl()->getLocation(), 3537 diag::note_attribute_overloadable_prev_overload); 3538 NewFD->addAttr(::new (Context) OverloadableAttr()); 3539 } 3540 3541 // If this is a locally-scoped extern C function, update the 3542 // map of such names. 3543 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3544 && !NewFD->isInvalidDecl()) 3545 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3546 3547 // Set this FunctionDecl's range up to the right paren. 3548 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3549 3550 if (FunctionTemplate && NewFD->isInvalidDecl()) 3551 FunctionTemplate->setInvalidDecl(); 3552 3553 if (FunctionTemplate) 3554 return FunctionTemplate; 3555 3556 3557 // Keep track of static, non-inlined function definitions that 3558 // have not been used. We will warn later. 3559 // FIXME: Also include static functions declared but not defined. 3560 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3561 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3562 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3563 && !NewFD->hasAttr<ConstructorAttr>() 3564 && !NewFD->hasAttr<DestructorAttr>()) 3565 UnusedStaticFuncs.push_back(NewFD); 3566 3567 return NewFD; 3568} 3569 3570/// \brief Perform semantic checking of a new function declaration. 3571/// 3572/// Performs semantic analysis of the new function declaration 3573/// NewFD. This routine performs all semantic checking that does not 3574/// require the actual declarator involved in the declaration, and is 3575/// used both for the declaration of functions as they are parsed 3576/// (called via ActOnDeclarator) and for the declaration of functions 3577/// that have been instantiated via C++ template instantiation (called 3578/// via InstantiateDecl). 3579/// 3580/// \param IsExplicitSpecialiation whether this new function declaration is 3581/// an explicit specialization of the previous declaration. 3582/// 3583/// This sets NewFD->isInvalidDecl() to true if there was an error. 3584void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3585 LookupResult &Previous, 3586 bool IsExplicitSpecialization, 3587 bool &Redeclaration, 3588 bool &OverloadableAttrRequired) { 3589 // If NewFD is already known erroneous, don't do any of this checking. 3590 if (NewFD->isInvalidDecl()) 3591 return; 3592 3593 if (NewFD->getResultType()->isVariablyModifiedType()) { 3594 // Functions returning a variably modified type violate C99 6.7.5.2p2 3595 // because all functions have linkage. 3596 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3597 return NewFD->setInvalidDecl(); 3598 } 3599 3600 if (NewFD->isMain()) 3601 CheckMain(NewFD); 3602 3603 // Check for a previous declaration of this name. 3604 if (Previous.empty() && NewFD->isExternC()) { 3605 // Since we did not find anything by this name and we're declaring 3606 // an extern "C" function, look for a non-visible extern "C" 3607 // declaration with the same name. 3608 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3609 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3610 if (Pos != LocallyScopedExternalDecls.end()) 3611 Previous.addDecl(Pos->second); 3612 } 3613 3614 // Merge or overload the declaration with an existing declaration of 3615 // the same name, if appropriate. 3616 if (!Previous.empty()) { 3617 // Determine whether NewFD is an overload of PrevDecl or 3618 // a declaration that requires merging. If it's an overload, 3619 // there's no more work to do here; we'll just add the new 3620 // function to the scope. 3621 3622 NamedDecl *OldDecl = 0; 3623 if (!AllowOverloadingOfFunction(Previous, Context)) { 3624 Redeclaration = true; 3625 OldDecl = Previous.getFoundDecl(); 3626 } else { 3627 if (!getLangOptions().CPlusPlus) { 3628 OverloadableAttrRequired = true; 3629 3630 // Functions marked "overloadable" must have a prototype (that 3631 // we can't get through declaration merging). 3632 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3633 Diag(NewFD->getLocation(), 3634 diag::err_attribute_overloadable_no_prototype) 3635 << NewFD; 3636 Redeclaration = true; 3637 3638 // Turn this into a variadic function with no parameters. 3639 QualType R = Context.getFunctionType( 3640 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3641 0, 0, true, 0, false, false, 0, 0, 3642 FunctionType::ExtInfo()); 3643 NewFD->setType(R); 3644 return NewFD->setInvalidDecl(); 3645 } 3646 } 3647 3648 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3649 /*NewIsUsingDecl*/ false)) { 3650 case Ovl_Match: 3651 Redeclaration = true; 3652 break; 3653 3654 case Ovl_NonFunction: 3655 Redeclaration = true; 3656 break; 3657 3658 case Ovl_Overload: 3659 Redeclaration = false; 3660 break; 3661 } 3662 } 3663 3664 if (Redeclaration) { 3665 // NewFD and OldDecl represent declarations that need to be 3666 // merged. 3667 if (MergeFunctionDecl(NewFD, OldDecl)) 3668 return NewFD->setInvalidDecl(); 3669 3670 Previous.clear(); 3671 Previous.addDecl(OldDecl); 3672 3673 if (FunctionTemplateDecl *OldTemplateDecl 3674 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3675 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3676 FunctionTemplateDecl *NewTemplateDecl 3677 = NewFD->getDescribedFunctionTemplate(); 3678 assert(NewTemplateDecl && "Template/non-template mismatch"); 3679 if (CXXMethodDecl *Method 3680 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3681 Method->setAccess(OldTemplateDecl->getAccess()); 3682 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3683 } 3684 3685 // If this is an explicit specialization of a member that is a function 3686 // template, mark it as a member specialization. 3687 if (IsExplicitSpecialization && 3688 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3689 NewTemplateDecl->setMemberSpecialization(); 3690 assert(OldTemplateDecl->isMemberSpecialization()); 3691 } 3692 } else { 3693 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3694 NewFD->setAccess(OldDecl->getAccess()); 3695 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3696 } 3697 } 3698 } 3699 3700 // Semantic checking for this function declaration (in isolation). 3701 if (getLangOptions().CPlusPlus) { 3702 // C++-specific checks. 3703 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3704 CheckConstructor(Constructor); 3705 } else if (CXXDestructorDecl *Destructor = 3706 dyn_cast<CXXDestructorDecl>(NewFD)) { 3707 CXXRecordDecl *Record = Destructor->getParent(); 3708 QualType ClassType = Context.getTypeDeclType(Record); 3709 3710 // FIXME: Shouldn't we be able to perform this check even when the class 3711 // type is dependent? Both gcc and edg can handle that. 3712 if (!ClassType->isDependentType()) { 3713 DeclarationName Name 3714 = Context.DeclarationNames.getCXXDestructorName( 3715 Context.getCanonicalType(ClassType)); 3716 if (NewFD->getDeclName() != Name) { 3717 Diag(NewFD->getLocation(), diag::err_destructor_name); 3718 return NewFD->setInvalidDecl(); 3719 } 3720 } 3721 3722 Record->setUserDeclaredDestructor(true); 3723 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3724 // user-defined destructor. 3725 Record->setPOD(false); 3726 3727 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3728 // declared destructor. 3729 // FIXME: C++0x: don't do this for "= default" destructors 3730 Record->setHasTrivialDestructor(false); 3731 } else if (CXXConversionDecl *Conversion 3732 = dyn_cast<CXXConversionDecl>(NewFD)) { 3733 ActOnConversionDeclarator(Conversion); 3734 } 3735 3736 // Find any virtual functions that this function overrides. 3737 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3738 if (!Method->isFunctionTemplateSpecialization() && 3739 !Method->getDescribedFunctionTemplate()) 3740 AddOverriddenMethods(Method->getParent(), Method); 3741 } 3742 3743 // Additional checks for the destructor; make sure we do this after we 3744 // figure out whether the destructor is virtual. 3745 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3746 if (!Destructor->getParent()->isDependentType()) 3747 CheckDestructor(Destructor); 3748 3749 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3750 if (NewFD->isOverloadedOperator() && 3751 CheckOverloadedOperatorDeclaration(NewFD)) 3752 return NewFD->setInvalidDecl(); 3753 3754 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3755 if (NewFD->getLiteralIdentifier() && 3756 CheckLiteralOperatorDeclaration(NewFD)) 3757 return NewFD->setInvalidDecl(); 3758 3759 // In C++, check default arguments now that we have merged decls. Unless 3760 // the lexical context is the class, because in this case this is done 3761 // during delayed parsing anyway. 3762 if (!CurContext->isRecord()) 3763 CheckCXXDefaultArguments(NewFD); 3764 } 3765} 3766 3767void Sema::CheckMain(FunctionDecl* FD) { 3768 // C++ [basic.start.main]p3: A program that declares main to be inline 3769 // or static is ill-formed. 3770 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3771 // shall not appear in a declaration of main. 3772 // static main is not an error under C99, but we should warn about it. 3773 bool isInline = FD->isInlineSpecified(); 3774 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3775 if (isInline || isStatic) { 3776 unsigned diagID = diag::warn_unusual_main_decl; 3777 if (isInline || getLangOptions().CPlusPlus) 3778 diagID = diag::err_unusual_main_decl; 3779 3780 int which = isStatic + (isInline << 1) - 1; 3781 Diag(FD->getLocation(), diagID) << which; 3782 } 3783 3784 QualType T = FD->getType(); 3785 assert(T->isFunctionType() && "function decl is not of function type"); 3786 const FunctionType* FT = T->getAs<FunctionType>(); 3787 3788 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3789 // TODO: add a replacement fixit to turn the return type into 'int'. 3790 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3791 FD->setInvalidDecl(true); 3792 } 3793 3794 // Treat protoless main() as nullary. 3795 if (isa<FunctionNoProtoType>(FT)) return; 3796 3797 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3798 unsigned nparams = FTP->getNumArgs(); 3799 assert(FD->getNumParams() == nparams); 3800 3801 bool HasExtraParameters = (nparams > 3); 3802 3803 // Darwin passes an undocumented fourth argument of type char**. If 3804 // other platforms start sprouting these, the logic below will start 3805 // getting shifty. 3806 if (nparams == 4 && 3807 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3808 HasExtraParameters = false; 3809 3810 if (HasExtraParameters) { 3811 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3812 FD->setInvalidDecl(true); 3813 nparams = 3; 3814 } 3815 3816 // FIXME: a lot of the following diagnostics would be improved 3817 // if we had some location information about types. 3818 3819 QualType CharPP = 3820 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3821 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3822 3823 for (unsigned i = 0; i < nparams; ++i) { 3824 QualType AT = FTP->getArgType(i); 3825 3826 bool mismatch = true; 3827 3828 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3829 mismatch = false; 3830 else if (Expected[i] == CharPP) { 3831 // As an extension, the following forms are okay: 3832 // char const ** 3833 // char const * const * 3834 // char * const * 3835 3836 QualifierCollector qs; 3837 const PointerType* PT; 3838 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3839 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3840 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3841 qs.removeConst(); 3842 mismatch = !qs.empty(); 3843 } 3844 } 3845 3846 if (mismatch) { 3847 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3848 // TODO: suggest replacing given type with expected type 3849 FD->setInvalidDecl(true); 3850 } 3851 } 3852 3853 if (nparams == 1 && !FD->isInvalidDecl()) { 3854 Diag(FD->getLocation(), diag::warn_main_one_arg); 3855 } 3856} 3857 3858bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3859 // FIXME: Need strict checking. In C89, we need to check for 3860 // any assignment, increment, decrement, function-calls, or 3861 // commas outside of a sizeof. In C99, it's the same list, 3862 // except that the aforementioned are allowed in unevaluated 3863 // expressions. Everything else falls under the 3864 // "may accept other forms of constant expressions" exception. 3865 // (We never end up here for C++, so the constant expression 3866 // rules there don't matter.) 3867 if (Init->isConstantInitializer(Context)) 3868 return false; 3869 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3870 << Init->getSourceRange(); 3871 return true; 3872} 3873 3874void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3875 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3876} 3877 3878/// AddInitializerToDecl - Adds the initializer Init to the 3879/// declaration dcl. If DirectInit is true, this is C++ direct 3880/// initialization rather than copy initialization. 3881void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3882 Decl *RealDecl = dcl.getAs<Decl>(); 3883 // If there is no declaration, there was an error parsing it. Just ignore 3884 // the initializer. 3885 if (RealDecl == 0) 3886 return; 3887 3888 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3889 // With declarators parsed the way they are, the parser cannot 3890 // distinguish between a normal initializer and a pure-specifier. 3891 // Thus this grotesque test. 3892 IntegerLiteral *IL; 3893 Expr *Init = static_cast<Expr *>(init.get()); 3894 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3895 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3896 CheckPureMethod(Method, Init->getSourceRange()); 3897 else { 3898 Diag(Method->getLocation(), diag::err_member_function_initialization) 3899 << Method->getDeclName() << Init->getSourceRange(); 3900 Method->setInvalidDecl(); 3901 } 3902 return; 3903 } 3904 3905 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3906 if (!VDecl) { 3907 if (getLangOptions().CPlusPlus && 3908 RealDecl->getLexicalDeclContext()->isRecord() && 3909 isa<NamedDecl>(RealDecl)) 3910 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3911 << cast<NamedDecl>(RealDecl)->getDeclName(); 3912 else 3913 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3914 RealDecl->setInvalidDecl(); 3915 return; 3916 } 3917 3918 // A definition must end up with a complete type, which means it must be 3919 // complete with the restriction that an array type might be completed by the 3920 // initializer; note that later code assumes this restriction. 3921 QualType BaseDeclType = VDecl->getType(); 3922 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3923 BaseDeclType = Array->getElementType(); 3924 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3925 diag::err_typecheck_decl_incomplete_type)) { 3926 RealDecl->setInvalidDecl(); 3927 return; 3928 } 3929 3930 // The variable can not have an abstract class type. 3931 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3932 diag::err_abstract_type_in_decl, 3933 AbstractVariableType)) 3934 VDecl->setInvalidDecl(); 3935 3936 const VarDecl *Def; 3937 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3938 Diag(VDecl->getLocation(), diag::err_redefinition) 3939 << VDecl->getDeclName(); 3940 Diag(Def->getLocation(), diag::note_previous_definition); 3941 VDecl->setInvalidDecl(); 3942 return; 3943 } 3944 3945 // Take ownership of the expression, now that we're sure we have somewhere 3946 // to put it. 3947 Expr *Init = init.takeAs<Expr>(); 3948 assert(Init && "missing initializer"); 3949 3950 // Capture the variable that is being initialized and the style of 3951 // initialization. 3952 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3953 3954 // FIXME: Poor source location information. 3955 InitializationKind Kind 3956 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3957 Init->getLocStart(), 3958 Init->getLocEnd()) 3959 : InitializationKind::CreateCopy(VDecl->getLocation(), 3960 Init->getLocStart()); 3961 3962 // Get the decls type and save a reference for later, since 3963 // CheckInitializerTypes may change it. 3964 QualType DclT = VDecl->getType(), SavT = DclT; 3965 if (VDecl->isBlockVarDecl()) { 3966 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3967 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3968 VDecl->setInvalidDecl(); 3969 } else if (!VDecl->isInvalidDecl()) { 3970 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3971 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3972 MultiExprArg(*this, (void**)&Init, 1), 3973 &DclT); 3974 if (Result.isInvalid()) { 3975 VDecl->setInvalidDecl(); 3976 return; 3977 } 3978 3979 Init = Result.takeAs<Expr>(); 3980 3981 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3982 // Don't check invalid declarations to avoid emitting useless diagnostics. 3983 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3984 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3985 CheckForConstantInitializer(Init, DclT); 3986 } 3987 } 3988 } else if (VDecl->isStaticDataMember() && 3989 VDecl->getLexicalDeclContext()->isRecord()) { 3990 // This is an in-class initialization for a static data member, e.g., 3991 // 3992 // struct S { 3993 // static const int value = 17; 3994 // }; 3995 3996 // Attach the initializer 3997 VDecl->setInit(Init); 3998 3999 // C++ [class.mem]p4: 4000 // A member-declarator can contain a constant-initializer only 4001 // if it declares a static member (9.4) of const integral or 4002 // const enumeration type, see 9.4.2. 4003 QualType T = VDecl->getType(); 4004 if (!T->isDependentType() && 4005 (!Context.getCanonicalType(T).isConstQualified() || 4006 !T->isIntegralOrEnumerationType())) { 4007 Diag(VDecl->getLocation(), diag::err_member_initialization) 4008 << VDecl->getDeclName() << Init->getSourceRange(); 4009 VDecl->setInvalidDecl(); 4010 } else { 4011 // C++ [class.static.data]p4: 4012 // If a static data member is of const integral or const 4013 // enumeration type, its declaration in the class definition 4014 // can specify a constant-initializer which shall be an 4015 // integral constant expression (5.19). 4016 if (!Init->isTypeDependent() && 4017 !Init->getType()->isIntegralOrEnumerationType()) { 4018 // We have a non-dependent, non-integral or enumeration type. 4019 Diag(Init->getSourceRange().getBegin(), 4020 diag::err_in_class_initializer_non_integral_type) 4021 << Init->getType() << Init->getSourceRange(); 4022 VDecl->setInvalidDecl(); 4023 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 4024 // Check whether the expression is a constant expression. 4025 llvm::APSInt Value; 4026 SourceLocation Loc; 4027 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4028 Diag(Loc, diag::err_in_class_initializer_non_constant) 4029 << Init->getSourceRange(); 4030 VDecl->setInvalidDecl(); 4031 } else if (!VDecl->getType()->isDependentType()) 4032 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 4033 } 4034 } 4035 } else if (VDecl->isFileVarDecl()) { 4036 if (VDecl->getStorageClass() == VarDecl::Extern && 4037 (!getLangOptions().CPlusPlus || 4038 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4039 Diag(VDecl->getLocation(), diag::warn_extern_init); 4040 if (!VDecl->isInvalidDecl()) { 4041 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4042 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4043 MultiExprArg(*this, (void**)&Init, 1), 4044 &DclT); 4045 if (Result.isInvalid()) { 4046 VDecl->setInvalidDecl(); 4047 return; 4048 } 4049 4050 Init = Result.takeAs<Expr>(); 4051 } 4052 4053 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4054 // Don't check invalid declarations to avoid emitting useless diagnostics. 4055 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4056 // C99 6.7.8p4. All file scoped initializers need to be constant. 4057 CheckForConstantInitializer(Init, DclT); 4058 } 4059 } 4060 // If the type changed, it means we had an incomplete type that was 4061 // completed by the initializer. For example: 4062 // int ary[] = { 1, 3, 5 }; 4063 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4064 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4065 VDecl->setType(DclT); 4066 Init->setType(DclT); 4067 } 4068 4069 Init = MaybeCreateCXXExprWithTemporaries(Init); 4070 // Attach the initializer to the decl. 4071 VDecl->setInit(Init); 4072 4073 if (getLangOptions().CPlusPlus) { 4074 // Make sure we mark the destructor as used if necessary. 4075 QualType InitType = VDecl->getType(); 4076 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4077 InitType = Context.getBaseElementType(Array); 4078 if (const RecordType *Record = InitType->getAs<RecordType>()) 4079 FinalizeVarWithDestructor(VDecl, Record); 4080 } 4081 4082 return; 4083} 4084 4085/// ActOnInitializerError - Given that there was an error parsing an 4086/// initializer for the given declaration, try to return to some form 4087/// of sanity. 4088void Sema::ActOnInitializerError(DeclPtrTy dcl) { 4089 // Our main concern here is re-establishing invariants like "a 4090 // variable's type is either dependent or complete". 4091 Decl *D = dcl.getAs<Decl>(); 4092 if (!D || D->isInvalidDecl()) return; 4093 4094 VarDecl *VD = dyn_cast<VarDecl>(D); 4095 if (!VD) return; 4096 4097 QualType Ty = VD->getType(); 4098 if (Ty->isDependentType()) return; 4099 4100 // Require a complete type. 4101 if (RequireCompleteType(VD->getLocation(), 4102 Context.getBaseElementType(Ty), 4103 diag::err_typecheck_decl_incomplete_type)) { 4104 VD->setInvalidDecl(); 4105 return; 4106 } 4107 4108 // Require an abstract type. 4109 if (RequireNonAbstractType(VD->getLocation(), Ty, 4110 diag::err_abstract_type_in_decl, 4111 AbstractVariableType)) { 4112 VD->setInvalidDecl(); 4113 return; 4114 } 4115 4116 // Don't bother complaining about constructors or destructors, 4117 // though. 4118} 4119 4120void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 4121 bool TypeContainsUndeducedAuto) { 4122 Decl *RealDecl = dcl.getAs<Decl>(); 4123 4124 // If there is no declaration, there was an error parsing it. Just ignore it. 4125 if (RealDecl == 0) 4126 return; 4127 4128 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4129 QualType Type = Var->getType(); 4130 4131 // C++0x [dcl.spec.auto]p3 4132 if (TypeContainsUndeducedAuto) { 4133 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4134 << Var->getDeclName() << Type; 4135 Var->setInvalidDecl(); 4136 return; 4137 } 4138 4139 switch (Var->isThisDeclarationADefinition()) { 4140 case VarDecl::Definition: 4141 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4142 break; 4143 4144 // We have an out-of-line definition of a static data member 4145 // that has an in-class initializer, so we type-check this like 4146 // a declaration. 4147 // 4148 // Fall through 4149 4150 case VarDecl::DeclarationOnly: 4151 // It's only a declaration. 4152 4153 // Block scope. C99 6.7p7: If an identifier for an object is 4154 // declared with no linkage (C99 6.2.2p6), the type for the 4155 // object shall be complete. 4156 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4157 !Var->getLinkage() && !Var->isInvalidDecl() && 4158 RequireCompleteType(Var->getLocation(), Type, 4159 diag::err_typecheck_decl_incomplete_type)) 4160 Var->setInvalidDecl(); 4161 4162 // Make sure that the type is not abstract. 4163 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4164 RequireNonAbstractType(Var->getLocation(), Type, 4165 diag::err_abstract_type_in_decl, 4166 AbstractVariableType)) 4167 Var->setInvalidDecl(); 4168 return; 4169 4170 case VarDecl::TentativeDefinition: 4171 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4172 // object that has file scope without an initializer, and without a 4173 // storage-class specifier or with the storage-class specifier "static", 4174 // constitutes a tentative definition. Note: A tentative definition with 4175 // external linkage is valid (C99 6.2.2p5). 4176 if (!Var->isInvalidDecl()) { 4177 if (const IncompleteArrayType *ArrayT 4178 = Context.getAsIncompleteArrayType(Type)) { 4179 if (RequireCompleteType(Var->getLocation(), 4180 ArrayT->getElementType(), 4181 diag::err_illegal_decl_array_incomplete_type)) 4182 Var->setInvalidDecl(); 4183 } else if (Var->getStorageClass() == VarDecl::Static) { 4184 // C99 6.9.2p3: If the declaration of an identifier for an object is 4185 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4186 // declared type shall not be an incomplete type. 4187 // NOTE: code such as the following 4188 // static struct s; 4189 // struct s { int a; }; 4190 // is accepted by gcc. Hence here we issue a warning instead of 4191 // an error and we do not invalidate the static declaration. 4192 // NOTE: to avoid multiple warnings, only check the first declaration. 4193 if (Var->getPreviousDeclaration() == 0) 4194 RequireCompleteType(Var->getLocation(), Type, 4195 diag::ext_typecheck_decl_incomplete_type); 4196 } 4197 } 4198 4199 // Record the tentative definition; we're done. 4200 if (!Var->isInvalidDecl()) 4201 TentativeDefinitions.push_back(Var); 4202 return; 4203 } 4204 4205 // Provide a specific diagnostic for uninitialized variable 4206 // definitions with incomplete array type. 4207 if (Type->isIncompleteArrayType()) { 4208 Diag(Var->getLocation(), 4209 diag::err_typecheck_incomplete_array_needs_initializer); 4210 Var->setInvalidDecl(); 4211 return; 4212 } 4213 4214 // Provide a specific diagnostic for uninitialized variable 4215 // definitions with reference type. 4216 if (Type->isReferenceType()) { 4217 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4218 << Var->getDeclName() 4219 << SourceRange(Var->getLocation(), Var->getLocation()); 4220 Var->setInvalidDecl(); 4221 return; 4222 } 4223 4224 // Do not attempt to type-check the default initializer for a 4225 // variable with dependent type. 4226 if (Type->isDependentType()) 4227 return; 4228 4229 if (Var->isInvalidDecl()) 4230 return; 4231 4232 if (RequireCompleteType(Var->getLocation(), 4233 Context.getBaseElementType(Type), 4234 diag::err_typecheck_decl_incomplete_type)) { 4235 Var->setInvalidDecl(); 4236 return; 4237 } 4238 4239 // The variable can not have an abstract class type. 4240 if (RequireNonAbstractType(Var->getLocation(), Type, 4241 diag::err_abstract_type_in_decl, 4242 AbstractVariableType)) { 4243 Var->setInvalidDecl(); 4244 return; 4245 } 4246 4247 const RecordType *Record 4248 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4249 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4250 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4251 // C++03 [dcl.init]p9: 4252 // If no initializer is specified for an object, and the 4253 // object is of (possibly cv-qualified) non-POD class type (or 4254 // array thereof), the object shall be default-initialized; if 4255 // the object is of const-qualified type, the underlying class 4256 // type shall have a user-declared default 4257 // constructor. Otherwise, if no initializer is specified for 4258 // a non- static object, the object and its subobjects, if 4259 // any, have an indeterminate initial value); if the object 4260 // or any of its subobjects are of const-qualified type, the 4261 // program is ill-formed. 4262 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4263 } else { 4264 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4265 InitializationKind Kind 4266 = InitializationKind::CreateDefault(Var->getLocation()); 4267 4268 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4269 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4270 MultiExprArg(*this, 0, 0)); 4271 if (Init.isInvalid()) 4272 Var->setInvalidDecl(); 4273 else if (Init.get()) 4274 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4275 } 4276 4277 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4278 FinalizeVarWithDestructor(Var, Record); 4279 } 4280} 4281 4282Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4283 DeclPtrTy *Group, 4284 unsigned NumDecls) { 4285 llvm::SmallVector<Decl*, 8> Decls; 4286 4287 if (DS.isTypeSpecOwned()) 4288 Decls.push_back((Decl*)DS.getTypeRep()); 4289 4290 for (unsigned i = 0; i != NumDecls; ++i) 4291 if (Decl *D = Group[i].getAs<Decl>()) 4292 Decls.push_back(D); 4293 4294 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4295 Decls.data(), Decls.size())); 4296} 4297 4298 4299/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4300/// to introduce parameters into function prototype scope. 4301Sema::DeclPtrTy 4302Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4303 const DeclSpec &DS = D.getDeclSpec(); 4304 4305 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4306 VarDecl::StorageClass StorageClass = VarDecl::None; 4307 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4308 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4309 StorageClass = VarDecl::Register; 4310 StorageClassAsWritten = VarDecl::Register; 4311 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4312 Diag(DS.getStorageClassSpecLoc(), 4313 diag::err_invalid_storage_class_in_func_decl); 4314 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4315 } 4316 4317 if (D.getDeclSpec().isThreadSpecified()) 4318 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4319 4320 DiagnoseFunctionSpecifiers(D); 4321 4322 // Check that there are no default arguments inside the type of this 4323 // parameter (C++ only). 4324 if (getLangOptions().CPlusPlus) 4325 CheckExtraCXXDefaultArguments(D); 4326 4327 TagDecl *OwnedDecl = 0; 4328 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4329 QualType parmDeclType = TInfo->getType(); 4330 4331 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4332 // C++ [dcl.fct]p6: 4333 // Types shall not be defined in return or parameter types. 4334 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4335 << Context.getTypeDeclType(OwnedDecl); 4336 } 4337 4338 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4339 IdentifierInfo *II = D.getIdentifier(); 4340 if (II) { 4341 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4342 ForRedeclaration); 4343 LookupName(R, S); 4344 if (R.isSingleResult()) { 4345 NamedDecl *PrevDecl = R.getFoundDecl(); 4346 if (PrevDecl->isTemplateParameter()) { 4347 // Maybe we will complain about the shadowed template parameter. 4348 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4349 // Just pretend that we didn't see the previous declaration. 4350 PrevDecl = 0; 4351 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4352 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4353 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4354 4355 // Recover by removing the name 4356 II = 0; 4357 D.SetIdentifier(0, D.getIdentifierLoc()); 4358 D.setInvalidType(true); 4359 } 4360 } 4361 } 4362 4363 // Temporarily put parameter variables in the translation unit, not 4364 // the enclosing context. This prevents them from accidentally 4365 // looking like class members in C++. 4366 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4367 TInfo, parmDeclType, II, 4368 D.getIdentifierLoc(), 4369 StorageClass, StorageClassAsWritten); 4370 4371 if (D.isInvalidType()) 4372 New->setInvalidDecl(); 4373 4374 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4375 if (D.getCXXScopeSpec().isSet()) { 4376 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4377 << D.getCXXScopeSpec().getRange(); 4378 New->setInvalidDecl(); 4379 } 4380 4381 // Add the parameter declaration into this scope. 4382 S->AddDecl(DeclPtrTy::make(New)); 4383 if (II) 4384 IdResolver.AddDecl(New); 4385 4386 ProcessDeclAttributes(S, New, D); 4387 4388 if (New->hasAttr<BlocksAttr>()) { 4389 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4390 } 4391 return DeclPtrTy::make(New); 4392} 4393 4394/// \brief Synthesizes a variable for a parameter arising from a 4395/// typedef. 4396ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4397 SourceLocation Loc, 4398 QualType T) { 4399 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4400 T, Context.getTrivialTypeSourceInfo(T, Loc), 4401 VarDecl::None, VarDecl::None, 0); 4402 Param->setImplicit(); 4403 return Param; 4404} 4405 4406ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4407 TypeSourceInfo *TSInfo, QualType T, 4408 IdentifierInfo *Name, 4409 SourceLocation NameLoc, 4410 VarDecl::StorageClass StorageClass, 4411 VarDecl::StorageClass StorageClassAsWritten) { 4412 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4413 adjustParameterType(T), TSInfo, 4414 StorageClass, StorageClassAsWritten, 4415 0); 4416 4417 // Parameters can not be abstract class types. 4418 // For record types, this is done by the AbstractClassUsageDiagnoser once 4419 // the class has been completely parsed. 4420 if (!CurContext->isRecord() && 4421 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4422 AbstractParamType)) 4423 New->setInvalidDecl(); 4424 4425 // Parameter declarators cannot be interface types. All ObjC objects are 4426 // passed by reference. 4427 if (T->isObjCObjectType()) { 4428 Diag(NameLoc, 4429 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4430 New->setInvalidDecl(); 4431 } 4432 4433 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4434 // duration shall not be qualified by an address-space qualifier." 4435 // Since all parameters have automatic store duration, they can not have 4436 // an address space. 4437 if (T.getAddressSpace() != 0) { 4438 Diag(NameLoc, diag::err_arg_with_address_space); 4439 New->setInvalidDecl(); 4440 } 4441 4442 return New; 4443} 4444 4445void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4446 SourceLocation LocAfterDecls) { 4447 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4448 "Not a function declarator!"); 4449 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4450 4451 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4452 // for a K&R function. 4453 if (!FTI.hasPrototype) { 4454 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4455 --i; 4456 if (FTI.ArgInfo[i].Param == 0) { 4457 llvm::SmallString<256> Code; 4458 llvm::raw_svector_ostream(Code) << " int " 4459 << FTI.ArgInfo[i].Ident->getName() 4460 << ";\n"; 4461 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4462 << FTI.ArgInfo[i].Ident 4463 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4464 4465 // Implicitly declare the argument as type 'int' for lack of a better 4466 // type. 4467 DeclSpec DS; 4468 const char* PrevSpec; // unused 4469 unsigned DiagID; // unused 4470 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4471 PrevSpec, DiagID); 4472 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4473 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4474 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4475 } 4476 } 4477 } 4478} 4479 4480Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4481 Declarator &D) { 4482 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4483 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4484 "Not a function declarator!"); 4485 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4486 4487 if (FTI.hasPrototype) { 4488 // FIXME: Diagnose arguments without names in C. 4489 } 4490 4491 Scope *ParentScope = FnBodyScope->getParent(); 4492 4493 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4494 MultiTemplateParamsArg(*this), 4495 /*IsFunctionDefinition=*/true); 4496 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4497} 4498 4499static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4500 // Don't warn about invalid declarations. 4501 if (FD->isInvalidDecl()) 4502 return false; 4503 4504 // Or declarations that aren't global. 4505 if (!FD->isGlobal()) 4506 return false; 4507 4508 // Don't warn about C++ member functions. 4509 if (isa<CXXMethodDecl>(FD)) 4510 return false; 4511 4512 // Don't warn about 'main'. 4513 if (FD->isMain()) 4514 return false; 4515 4516 // Don't warn about inline functions. 4517 if (FD->isInlineSpecified()) 4518 return false; 4519 4520 // Don't warn about function templates. 4521 if (FD->getDescribedFunctionTemplate()) 4522 return false; 4523 4524 // Don't warn about function template specializations. 4525 if (FD->isFunctionTemplateSpecialization()) 4526 return false; 4527 4528 bool MissingPrototype = true; 4529 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4530 Prev; Prev = Prev->getPreviousDeclaration()) { 4531 // Ignore any declarations that occur in function or method 4532 // scope, because they aren't visible from the header. 4533 if (Prev->getDeclContext()->isFunctionOrMethod()) 4534 continue; 4535 4536 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4537 break; 4538 } 4539 4540 return MissingPrototype; 4541} 4542 4543Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4544 // Clear the last template instantiation error context. 4545 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4546 4547 if (!D) 4548 return D; 4549 FunctionDecl *FD = 0; 4550 4551 if (FunctionTemplateDecl *FunTmpl 4552 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4553 FD = FunTmpl->getTemplatedDecl(); 4554 else 4555 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4556 4557 // Enter a new function scope 4558 PushFunctionScope(); 4559 4560 // See if this is a redefinition. 4561 // But don't complain if we're in GNU89 mode and the previous definition 4562 // was an extern inline function. 4563 const FunctionDecl *Definition; 4564 if (FD->hasBody(Definition) && 4565 !canRedefineFunction(Definition, getLangOptions())) { 4566 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4567 Diag(Definition->getLocation(), diag::note_previous_definition); 4568 } 4569 4570 // Builtin functions cannot be defined. 4571 if (unsigned BuiltinID = FD->getBuiltinID()) { 4572 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4573 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4574 FD->setInvalidDecl(); 4575 } 4576 } 4577 4578 // The return type of a function definition must be complete 4579 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4580 QualType ResultType = FD->getResultType(); 4581 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4582 !FD->isInvalidDecl() && 4583 RequireCompleteType(FD->getLocation(), ResultType, 4584 diag::err_func_def_incomplete_result)) 4585 FD->setInvalidDecl(); 4586 4587 // GNU warning -Wmissing-prototypes: 4588 // Warn if a global function is defined without a previous 4589 // prototype declaration. This warning is issued even if the 4590 // definition itself provides a prototype. The aim is to detect 4591 // global functions that fail to be declared in header files. 4592 if (ShouldWarnAboutMissingPrototype(FD)) 4593 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4594 4595 if (FnBodyScope) 4596 PushDeclContext(FnBodyScope, FD); 4597 4598 // Check the validity of our function parameters 4599 CheckParmsForFunctionDef(FD); 4600 4601 bool ShouldCheckShadow = 4602 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4603 4604 // Introduce our parameters into the function scope 4605 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4606 ParmVarDecl *Param = FD->getParamDecl(p); 4607 Param->setOwningFunction(FD); 4608 4609 // If this has an identifier, add it to the scope stack. 4610 if (Param->getIdentifier() && FnBodyScope) { 4611 if (ShouldCheckShadow) 4612 CheckShadow(FnBodyScope, Param); 4613 4614 PushOnScopeChains(Param, FnBodyScope); 4615 } 4616 } 4617 4618 // Checking attributes of current function definition 4619 // dllimport attribute. 4620 if (FD->getAttr<DLLImportAttr>() && 4621 (!FD->getAttr<DLLExportAttr>())) { 4622 // dllimport attribute cannot be applied to definition. 4623 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4624 Diag(FD->getLocation(), 4625 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4626 << "dllimport"; 4627 FD->setInvalidDecl(); 4628 return DeclPtrTy::make(FD); 4629 } 4630 4631 // Visual C++ appears to not think this is an issue, so only issue 4632 // a warning when Microsoft extensions are disabled. 4633 if (!LangOpts.Microsoft) { 4634 // If a symbol previously declared dllimport is later defined, the 4635 // attribute is ignored in subsequent references, and a warning is 4636 // emitted. 4637 Diag(FD->getLocation(), 4638 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4639 << FD->getNameAsCString() << "dllimport"; 4640 } 4641 } 4642 return DeclPtrTy::make(FD); 4643} 4644 4645/// \brief Given the set of return statements within a function body, 4646/// compute the variables that are subject to the named return value 4647/// optimization. 4648/// 4649/// Each of the variables that is subject to the named return value 4650/// optimization will be marked as NRVO variables in the AST, and any 4651/// return statement that has a marked NRVO variable as its NRVO candidate can 4652/// use the named return value optimization. 4653/// 4654/// This function applies a very simplistic algorithm for NRVO: if every return 4655/// statement in the function has the same NRVO candidate, that candidate is 4656/// the NRVO variable. 4657/// 4658/// FIXME: Employ a smarter algorithm that accounts for multiple return 4659/// statements and the lifetimes of the NRVO candidates. We should be able to 4660/// find a maximal set of NRVO variables. 4661static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4662 const VarDecl *NRVOCandidate = 0; 4663 for (unsigned I = 0; I != NumReturns; ++I) { 4664 if (!Returns[I]->getNRVOCandidate()) 4665 return; 4666 4667 if (!NRVOCandidate) 4668 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4669 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4670 return; 4671 } 4672 4673 if (NRVOCandidate) 4674 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4675} 4676 4677Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4678 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4679} 4680 4681Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4682 bool IsInstantiation) { 4683 Decl *dcl = D.getAs<Decl>(); 4684 Stmt *Body = BodyArg.takeAs<Stmt>(); 4685 4686 FunctionDecl *FD = 0; 4687 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4688 if (FunTmpl) 4689 FD = FunTmpl->getTemplatedDecl(); 4690 else 4691 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4692 4693 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4694 4695 if (FD) { 4696 FD->setBody(Body); 4697 if (FD->isMain()) { 4698 // C and C++ allow for main to automagically return 0. 4699 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4700 FD->setHasImplicitReturnZero(true); 4701 WP.disableCheckFallThrough(); 4702 } 4703 4704 if (!FD->isInvalidDecl()) { 4705 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4706 4707 // If this is a constructor, we need a vtable. 4708 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4709 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4710 4711 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4712 FunctionScopes.back()->Returns.size()); 4713 } 4714 4715 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4716 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4717 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4718 MD->setBody(Body); 4719 MD->setEndLoc(Body->getLocEnd()); 4720 if (!MD->isInvalidDecl()) 4721 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4722 } else { 4723 Body->Destroy(Context); 4724 return DeclPtrTy(); 4725 } 4726 4727 // Verify and clean out per-function state. 4728 4729 // Check goto/label use. 4730 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4731 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4732 LabelStmt *L = I->second; 4733 4734 // Verify that we have no forward references left. If so, there was a goto 4735 // or address of a label taken, but no definition of it. Label fwd 4736 // definitions are indicated with a null substmt. 4737 if (L->getSubStmt() != 0) 4738 continue; 4739 4740 // Emit error. 4741 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4742 4743 // At this point, we have gotos that use the bogus label. Stitch it into 4744 // the function body so that they aren't leaked and that the AST is well 4745 // formed. 4746 if (Body == 0) { 4747 // The whole function wasn't parsed correctly, just delete this. 4748 L->Destroy(Context); 4749 continue; 4750 } 4751 4752 // Otherwise, the body is valid: we want to stitch the label decl into the 4753 // function somewhere so that it is properly owned and so that the goto 4754 // has a valid target. Do this by creating a new compound stmt with the 4755 // label in it. 4756 4757 // Give the label a sub-statement. 4758 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4759 4760 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4761 cast<CXXTryStmt>(Body)->getTryBlock() : 4762 cast<CompoundStmt>(Body); 4763 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4764 Compound->body_end()); 4765 Elements.push_back(L); 4766 Compound->setStmts(Context, Elements.data(), Elements.size()); 4767 } 4768 4769 if (Body) { 4770 // C++ constructors that have function-try-blocks can't have return 4771 // statements in the handlers of that block. (C++ [except.handle]p14) 4772 // Verify this. 4773 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4774 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4775 4776 // Verify that that gotos and switch cases don't jump into scopes illegally. 4777 // Verify that that gotos and switch cases don't jump into scopes illegally. 4778 if (FunctionNeedsScopeChecking() && 4779 !dcl->isInvalidDecl() && 4780 !hasAnyErrorsInThisFunction()) 4781 DiagnoseInvalidJumps(Body); 4782 4783 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4784 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4785 Destructor->getParent()); 4786 4787 // If any errors have occurred, clear out any temporaries that may have 4788 // been leftover. This ensures that these temporaries won't be picked up for 4789 // deletion in some later function. 4790 if (PP.getDiagnostics().hasErrorOccurred()) 4791 ExprTemporaries.clear(); 4792 else if (!isa<FunctionTemplateDecl>(dcl)) { 4793 // Since the body is valid, issue any analysis-based warnings that are 4794 // enabled. 4795 QualType ResultType; 4796 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4797 ResultType = FD->getResultType(); 4798 } 4799 else { 4800 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4801 ResultType = MD->getResultType(); 4802 } 4803 AnalysisWarnings.IssueWarnings(WP, dcl); 4804 } 4805 4806 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4807 } 4808 4809 if (!IsInstantiation) 4810 PopDeclContext(); 4811 4812 PopFunctionOrBlockScope(); 4813 4814 // If any errors have occurred, clear out any temporaries that may have 4815 // been leftover. This ensures that these temporaries won't be picked up for 4816 // deletion in some later function. 4817 if (getDiagnostics().hasErrorOccurred()) 4818 ExprTemporaries.clear(); 4819 4820 return D; 4821} 4822 4823/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4824/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4825NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4826 IdentifierInfo &II, Scope *S) { 4827 // Before we produce a declaration for an implicitly defined 4828 // function, see whether there was a locally-scoped declaration of 4829 // this name as a function or variable. If so, use that 4830 // (non-visible) declaration, and complain about it. 4831 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4832 = LocallyScopedExternalDecls.find(&II); 4833 if (Pos != LocallyScopedExternalDecls.end()) { 4834 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4835 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4836 return Pos->second; 4837 } 4838 4839 // Extension in C99. Legal in C90, but warn about it. 4840 if (II.getName().startswith("__builtin_")) 4841 Diag(Loc, diag::warn_builtin_unknown) << &II; 4842 else if (getLangOptions().C99) 4843 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4844 else 4845 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4846 4847 // Set a Declarator for the implicit definition: int foo(); 4848 const char *Dummy; 4849 DeclSpec DS; 4850 unsigned DiagID; 4851 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4852 Error = Error; // Silence warning. 4853 assert(!Error && "Error setting up implicit decl!"); 4854 Declarator D(DS, Declarator::BlockContext); 4855 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4856 0, 0, false, SourceLocation(), 4857 false, 0,0,0, Loc, Loc, D), 4858 SourceLocation()); 4859 D.SetIdentifier(&II, Loc); 4860 4861 // Insert this function into translation-unit scope. 4862 4863 DeclContext *PrevDC = CurContext; 4864 CurContext = Context.getTranslationUnitDecl(); 4865 4866 FunctionDecl *FD = 4867 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4868 FD->setImplicit(); 4869 4870 CurContext = PrevDC; 4871 4872 AddKnownFunctionAttributes(FD); 4873 4874 return FD; 4875} 4876 4877/// \brief Adds any function attributes that we know a priori based on 4878/// the declaration of this function. 4879/// 4880/// These attributes can apply both to implicitly-declared builtins 4881/// (like __builtin___printf_chk) or to library-declared functions 4882/// like NSLog or printf. 4883void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4884 if (FD->isInvalidDecl()) 4885 return; 4886 4887 // If this is a built-in function, map its builtin attributes to 4888 // actual attributes. 4889 if (unsigned BuiltinID = FD->getBuiltinID()) { 4890 // Handle printf-formatting attributes. 4891 unsigned FormatIdx; 4892 bool HasVAListArg; 4893 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4894 if (!FD->getAttr<FormatAttr>()) 4895 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4896 HasVAListArg ? 0 : FormatIdx+2)); 4897 } 4898 4899 // Mark const if we don't care about errno and that is the only 4900 // thing preventing the function from being const. This allows 4901 // IRgen to use LLVM intrinsics for such functions. 4902 if (!getLangOptions().MathErrno && 4903 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4904 if (!FD->getAttr<ConstAttr>()) 4905 FD->addAttr(::new (Context) ConstAttr()); 4906 } 4907 4908 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4909 FD->setType(Context.getNoReturnType(FD->getType())); 4910 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4911 FD->addAttr(::new (Context) NoThrowAttr()); 4912 if (Context.BuiltinInfo.isConst(BuiltinID)) 4913 FD->addAttr(::new (Context) ConstAttr()); 4914 } 4915 4916 IdentifierInfo *Name = FD->getIdentifier(); 4917 if (!Name) 4918 return; 4919 if ((!getLangOptions().CPlusPlus && 4920 FD->getDeclContext()->isTranslationUnit()) || 4921 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4922 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4923 LinkageSpecDecl::lang_c)) { 4924 // Okay: this could be a libc/libm/Objective-C function we know 4925 // about. 4926 } else 4927 return; 4928 4929 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4930 // FIXME: NSLog and NSLogv should be target specific 4931 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4932 // FIXME: We known better than our headers. 4933 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4934 } else 4935 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4936 Name->isStr("NSLogv") ? 0 : 2)); 4937 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4938 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4939 // target-specific builtins, perhaps? 4940 if (!FD->getAttr<FormatAttr>()) 4941 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4942 Name->isStr("vasprintf") ? 0 : 3)); 4943 } 4944} 4945 4946TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4947 TypeSourceInfo *TInfo) { 4948 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4949 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4950 4951 if (!TInfo) { 4952 assert(D.isInvalidType() && "no declarator info for valid type"); 4953 TInfo = Context.getTrivialTypeSourceInfo(T); 4954 } 4955 4956 // Scope manipulation handled by caller. 4957 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4958 D.getIdentifierLoc(), 4959 D.getIdentifier(), 4960 TInfo); 4961 4962 if (const TagType *TT = T->getAs<TagType>()) { 4963 TagDecl *TD = TT->getDecl(); 4964 4965 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4966 // keep track of the TypedefDecl. 4967 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4968 TD->setTypedefForAnonDecl(NewTD); 4969 } 4970 4971 if (D.isInvalidType()) 4972 NewTD->setInvalidDecl(); 4973 return NewTD; 4974} 4975 4976 4977/// \brief Determine whether a tag with a given kind is acceptable 4978/// as a redeclaration of the given tag declaration. 4979/// 4980/// \returns true if the new tag kind is acceptable, false otherwise. 4981bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4982 TagTypeKind NewTag, 4983 SourceLocation NewTagLoc, 4984 const IdentifierInfo &Name) { 4985 // C++ [dcl.type.elab]p3: 4986 // The class-key or enum keyword present in the 4987 // elaborated-type-specifier shall agree in kind with the 4988 // declaration to which the name in the elaborated-type-specifier 4989 // refers. This rule also applies to the form of 4990 // elaborated-type-specifier that declares a class-name or 4991 // friend class since it can be construed as referring to the 4992 // definition of the class. Thus, in any 4993 // elaborated-type-specifier, the enum keyword shall be used to 4994 // refer to an enumeration (7.2), the union class-key shall be 4995 // used to refer to a union (clause 9), and either the class or 4996 // struct class-key shall be used to refer to a class (clause 9) 4997 // declared using the class or struct class-key. 4998 TagTypeKind OldTag = Previous->getTagKind(); 4999 if (OldTag == NewTag) 5000 return true; 5001 5002 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5003 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5004 // Warn about the struct/class tag mismatch. 5005 bool isTemplate = false; 5006 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5007 isTemplate = Record->getDescribedClassTemplate(); 5008 5009 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5010 << (NewTag == TTK_Class) 5011 << isTemplate << &Name 5012 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5013 OldTag == TTK_Class? "class" : "struct"); 5014 Diag(Previous->getLocation(), diag::note_previous_use); 5015 return true; 5016 } 5017 return false; 5018} 5019 5020/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5021/// former case, Name will be non-null. In the later case, Name will be null. 5022/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5023/// reference/declaration/definition of a tag. 5024Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5025 SourceLocation KWLoc, CXXScopeSpec &SS, 5026 IdentifierInfo *Name, SourceLocation NameLoc, 5027 AttributeList *Attr, AccessSpecifier AS, 5028 MultiTemplateParamsArg TemplateParameterLists, 5029 bool &OwnedDecl, bool &IsDependent) { 5030 // If this is not a definition, it must have a name. 5031 assert((Name != 0 || TUK == TUK_Definition) && 5032 "Nameless record must be a definition!"); 5033 5034 OwnedDecl = false; 5035 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5036 5037 // FIXME: Check explicit specializations more carefully. 5038 bool isExplicitSpecialization = false; 5039 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5040 if (TUK != TUK_Reference) { 5041 if (TemplateParameterList *TemplateParams 5042 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5043 (TemplateParameterList**)TemplateParameterLists.get(), 5044 TemplateParameterLists.size(), 5045 TUK == TUK_Friend, 5046 isExplicitSpecialization)) { 5047 // All but one template parameter lists have been matching. 5048 --NumMatchedTemplateParamLists; 5049 5050 if (TemplateParams->size() > 0) { 5051 // This is a declaration or definition of a class template (which may 5052 // be a member of another template). 5053 OwnedDecl = false; 5054 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5055 SS, Name, NameLoc, Attr, 5056 TemplateParams, 5057 AS); 5058 TemplateParameterLists.release(); 5059 return Result.get(); 5060 } else { 5061 // The "template<>" header is extraneous. 5062 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5063 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5064 isExplicitSpecialization = true; 5065 } 5066 } 5067 } 5068 5069 DeclContext *SearchDC = CurContext; 5070 DeclContext *DC = CurContext; 5071 bool isStdBadAlloc = false; 5072 bool Invalid = false; 5073 5074 RedeclarationKind Redecl = ForRedeclaration; 5075 if (TUK == TUK_Friend || TUK == TUK_Reference) 5076 Redecl = NotForRedeclaration; 5077 5078 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5079 5080 if (Name && SS.isNotEmpty()) { 5081 // We have a nested-name tag ('struct foo::bar'). 5082 5083 // Check for invalid 'foo::'. 5084 if (SS.isInvalid()) { 5085 Name = 0; 5086 goto CreateNewDecl; 5087 } 5088 5089 // If this is a friend or a reference to a class in a dependent 5090 // context, don't try to make a decl for it. 5091 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5092 DC = computeDeclContext(SS, false); 5093 if (!DC) { 5094 IsDependent = true; 5095 return DeclPtrTy(); 5096 } 5097 } else { 5098 DC = computeDeclContext(SS, true); 5099 if (!DC) { 5100 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5101 << SS.getRange(); 5102 return DeclPtrTy(); 5103 } 5104 } 5105 5106 if (RequireCompleteDeclContext(SS, DC)) 5107 return DeclPtrTy::make((Decl *)0); 5108 5109 SearchDC = DC; 5110 // Look-up name inside 'foo::'. 5111 LookupQualifiedName(Previous, DC); 5112 5113 if (Previous.isAmbiguous()) 5114 return DeclPtrTy(); 5115 5116 if (Previous.empty()) { 5117 // Name lookup did not find anything. However, if the 5118 // nested-name-specifier refers to the current instantiation, 5119 // and that current instantiation has any dependent base 5120 // classes, we might find something at instantiation time: treat 5121 // this as a dependent elaborated-type-specifier. 5122 if (Previous.wasNotFoundInCurrentInstantiation()) { 5123 IsDependent = true; 5124 return DeclPtrTy(); 5125 } 5126 5127 // A tag 'foo::bar' must already exist. 5128 Diag(NameLoc, diag::err_not_tag_in_scope) 5129 << Kind << Name << DC << SS.getRange(); 5130 Name = 0; 5131 Invalid = true; 5132 goto CreateNewDecl; 5133 } 5134 } else if (Name) { 5135 // If this is a named struct, check to see if there was a previous forward 5136 // declaration or definition. 5137 // FIXME: We're looking into outer scopes here, even when we 5138 // shouldn't be. Doing so can result in ambiguities that we 5139 // shouldn't be diagnosing. 5140 LookupName(Previous, S); 5141 5142 // Note: there used to be some attempt at recovery here. 5143 if (Previous.isAmbiguous()) 5144 return DeclPtrTy(); 5145 5146 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5147 // FIXME: This makes sure that we ignore the contexts associated 5148 // with C structs, unions, and enums when looking for a matching 5149 // tag declaration or definition. See the similar lookup tweak 5150 // in Sema::LookupName; is there a better way to deal with this? 5151 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5152 SearchDC = SearchDC->getParent(); 5153 } 5154 } 5155 5156 if (Previous.isSingleResult() && 5157 Previous.getFoundDecl()->isTemplateParameter()) { 5158 // Maybe we will complain about the shadowed template parameter. 5159 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5160 // Just pretend that we didn't see the previous declaration. 5161 Previous.clear(); 5162 } 5163 5164 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5165 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 5166 // This is a declaration of or a reference to "std::bad_alloc". 5167 isStdBadAlloc = true; 5168 5169 if (Previous.empty() && StdBadAlloc) { 5170 // std::bad_alloc has been implicitly declared (but made invisible to 5171 // name lookup). Fill in this implicit declaration as the previous 5172 // declaration, so that the declarations get chained appropriately. 5173 Previous.addDecl(StdBadAlloc); 5174 } 5175 } 5176 5177 // If we didn't find a previous declaration, and this is a reference 5178 // (or friend reference), move to the correct scope. In C++, we 5179 // also need to do a redeclaration lookup there, just in case 5180 // there's a shadow friend decl. 5181 if (Name && Previous.empty() && 5182 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5183 if (Invalid) goto CreateNewDecl; 5184 assert(SS.isEmpty()); 5185 5186 if (TUK == TUK_Reference) { 5187 // C++ [basic.scope.pdecl]p5: 5188 // -- for an elaborated-type-specifier of the form 5189 // 5190 // class-key identifier 5191 // 5192 // if the elaborated-type-specifier is used in the 5193 // decl-specifier-seq or parameter-declaration-clause of a 5194 // function defined in namespace scope, the identifier is 5195 // declared as a class-name in the namespace that contains 5196 // the declaration; otherwise, except as a friend 5197 // declaration, the identifier is declared in the smallest 5198 // non-class, non-function-prototype scope that contains the 5199 // declaration. 5200 // 5201 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5202 // C structs and unions. 5203 // 5204 // It is an error in C++ to declare (rather than define) an enum 5205 // type, including via an elaborated type specifier. We'll 5206 // diagnose that later; for now, declare the enum in the same 5207 // scope as we would have picked for any other tag type. 5208 // 5209 // GNU C also supports this behavior as part of its incomplete 5210 // enum types extension, while GNU C++ does not. 5211 // 5212 // Find the context where we'll be declaring the tag. 5213 // FIXME: We would like to maintain the current DeclContext as the 5214 // lexical context, 5215 while (SearchDC->isRecord()) 5216 SearchDC = SearchDC->getParent(); 5217 5218 // Find the scope where we'll be declaring the tag. 5219 while (S->isClassScope() || 5220 (getLangOptions().CPlusPlus && 5221 S->isFunctionPrototypeScope()) || 5222 ((S->getFlags() & Scope::DeclScope) == 0) || 5223 (S->getEntity() && 5224 ((DeclContext *)S->getEntity())->isTransparentContext())) 5225 S = S->getParent(); 5226 } else { 5227 assert(TUK == TUK_Friend); 5228 // C++ [namespace.memdef]p3: 5229 // If a friend declaration in a non-local class first declares a 5230 // class or function, the friend class or function is a member of 5231 // the innermost enclosing namespace. 5232 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5233 } 5234 5235 // In C++, we need to do a redeclaration lookup to properly 5236 // diagnose some problems. 5237 if (getLangOptions().CPlusPlus) { 5238 Previous.setRedeclarationKind(ForRedeclaration); 5239 LookupQualifiedName(Previous, SearchDC); 5240 } 5241 } 5242 5243 if (!Previous.empty()) { 5244 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5245 5246 // It's okay to have a tag decl in the same scope as a typedef 5247 // which hides a tag decl in the same scope. Finding this 5248 // insanity with a redeclaration lookup can only actually happen 5249 // in C++. 5250 // 5251 // This is also okay for elaborated-type-specifiers, which is 5252 // technically forbidden by the current standard but which is 5253 // okay according to the likely resolution of an open issue; 5254 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5255 if (getLangOptions().CPlusPlus) { 5256 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5257 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5258 TagDecl *Tag = TT->getDecl(); 5259 if (Tag->getDeclName() == Name && 5260 Tag->getDeclContext()->getLookupContext() 5261 ->Equals(TD->getDeclContext()->getLookupContext())) { 5262 PrevDecl = Tag; 5263 Previous.clear(); 5264 Previous.addDecl(Tag); 5265 } 5266 } 5267 } 5268 } 5269 5270 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5271 // If this is a use of a previous tag, or if the tag is already declared 5272 // in the same scope (so that the definition/declaration completes or 5273 // rementions the tag), reuse the decl. 5274 if (TUK == TUK_Reference || TUK == TUK_Friend || 5275 isDeclInScope(PrevDecl, SearchDC, S)) { 5276 // Make sure that this wasn't declared as an enum and now used as a 5277 // struct or something similar. 5278 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5279 bool SafeToContinue 5280 = (PrevTagDecl->getTagKind() != TTK_Enum && 5281 Kind != TTK_Enum); 5282 if (SafeToContinue) 5283 Diag(KWLoc, diag::err_use_with_wrong_tag) 5284 << Name 5285 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5286 PrevTagDecl->getKindName()); 5287 else 5288 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5289 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5290 5291 if (SafeToContinue) 5292 Kind = PrevTagDecl->getTagKind(); 5293 else { 5294 // Recover by making this an anonymous redefinition. 5295 Name = 0; 5296 Previous.clear(); 5297 Invalid = true; 5298 } 5299 } 5300 5301 if (!Invalid) { 5302 // If this is a use, just return the declaration we found. 5303 5304 // FIXME: In the future, return a variant or some other clue 5305 // for the consumer of this Decl to know it doesn't own it. 5306 // For our current ASTs this shouldn't be a problem, but will 5307 // need to be changed with DeclGroups. 5308 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5309 TUK == TUK_Friend) 5310 return DeclPtrTy::make(PrevTagDecl); 5311 5312 // Diagnose attempts to redefine a tag. 5313 if (TUK == TUK_Definition) { 5314 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5315 // If we're defining a specialization and the previous definition 5316 // is from an implicit instantiation, don't emit an error 5317 // here; we'll catch this in the general case below. 5318 if (!isExplicitSpecialization || 5319 !isa<CXXRecordDecl>(Def) || 5320 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5321 == TSK_ExplicitSpecialization) { 5322 Diag(NameLoc, diag::err_redefinition) << Name; 5323 Diag(Def->getLocation(), diag::note_previous_definition); 5324 // If this is a redefinition, recover by making this 5325 // struct be anonymous, which will make any later 5326 // references get the previous definition. 5327 Name = 0; 5328 Previous.clear(); 5329 Invalid = true; 5330 } 5331 } else { 5332 // If the type is currently being defined, complain 5333 // about a nested redefinition. 5334 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5335 if (Tag->isBeingDefined()) { 5336 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5337 Diag(PrevTagDecl->getLocation(), 5338 diag::note_previous_definition); 5339 Name = 0; 5340 Previous.clear(); 5341 Invalid = true; 5342 } 5343 } 5344 5345 // Okay, this is definition of a previously declared or referenced 5346 // tag PrevDecl. We're going to create a new Decl for it. 5347 } 5348 } 5349 // If we get here we have (another) forward declaration or we 5350 // have a definition. Just create a new decl. 5351 5352 } else { 5353 // If we get here, this is a definition of a new tag type in a nested 5354 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5355 // new decl/type. We set PrevDecl to NULL so that the entities 5356 // have distinct types. 5357 Previous.clear(); 5358 } 5359 // If we get here, we're going to create a new Decl. If PrevDecl 5360 // is non-NULL, it's a definition of the tag declared by 5361 // PrevDecl. If it's NULL, we have a new definition. 5362 5363 5364 // Otherwise, PrevDecl is not a tag, but was found with tag 5365 // lookup. This is only actually possible in C++, where a few 5366 // things like templates still live in the tag namespace. 5367 } else { 5368 assert(getLangOptions().CPlusPlus); 5369 5370 // Use a better diagnostic if an elaborated-type-specifier 5371 // found the wrong kind of type on the first 5372 // (non-redeclaration) lookup. 5373 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5374 !Previous.isForRedeclaration()) { 5375 unsigned Kind = 0; 5376 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5377 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5378 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5379 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5380 Invalid = true; 5381 5382 // Otherwise, only diagnose if the declaration is in scope. 5383 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5384 // do nothing 5385 5386 // Diagnose implicit declarations introduced by elaborated types. 5387 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5388 unsigned Kind = 0; 5389 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5390 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5391 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5392 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5393 Invalid = true; 5394 5395 // Otherwise it's a declaration. Call out a particularly common 5396 // case here. 5397 } else if (isa<TypedefDecl>(PrevDecl)) { 5398 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5399 << Name 5400 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5401 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5402 Invalid = true; 5403 5404 // Otherwise, diagnose. 5405 } else { 5406 // The tag name clashes with something else in the target scope, 5407 // issue an error and recover by making this tag be anonymous. 5408 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5409 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5410 Name = 0; 5411 Invalid = true; 5412 } 5413 5414 // The existing declaration isn't relevant to us; we're in a 5415 // new scope, so clear out the previous declaration. 5416 Previous.clear(); 5417 } 5418 } 5419 5420CreateNewDecl: 5421 5422 TagDecl *PrevDecl = 0; 5423 if (Previous.isSingleResult()) 5424 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5425 5426 // If there is an identifier, use the location of the identifier as the 5427 // location of the decl, otherwise use the location of the struct/union 5428 // keyword. 5429 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5430 5431 // Otherwise, create a new declaration. If there is a previous 5432 // declaration of the same entity, the two will be linked via 5433 // PrevDecl. 5434 TagDecl *New; 5435 5436 if (Kind == TTK_Enum) { 5437 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5438 // enum X { A, B, C } D; D should chain to X. 5439 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5440 cast_or_null<EnumDecl>(PrevDecl)); 5441 // If this is an undefined enum, warn. 5442 if (TUK != TUK_Definition && !Invalid) { 5443 TagDecl *Def; 5444 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5445 Diag(Loc, diag::ext_forward_ref_enum_def) 5446 << New; 5447 Diag(Def->getLocation(), diag::note_previous_definition); 5448 } else { 5449 Diag(Loc, 5450 getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5451 : diag::ext_forward_ref_enum); 5452 } 5453 } 5454 } else { 5455 // struct/union/class 5456 5457 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5458 // struct X { int A; } D; D should chain to X. 5459 if (getLangOptions().CPlusPlus) { 5460 // FIXME: Look for a way to use RecordDecl for simple structs. 5461 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5462 cast_or_null<CXXRecordDecl>(PrevDecl)); 5463 5464 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5465 StdBadAlloc = cast<CXXRecordDecl>(New); 5466 } else 5467 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5468 cast_or_null<RecordDecl>(PrevDecl)); 5469 } 5470 5471 // Maybe add qualifier info. 5472 if (SS.isNotEmpty()) { 5473 if (SS.isSet()) { 5474 NestedNameSpecifier *NNS 5475 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5476 New->setQualifierInfo(NNS, SS.getRange()); 5477 if (NumMatchedTemplateParamLists > 0) { 5478 New->setTemplateParameterListsInfo(Context, 5479 NumMatchedTemplateParamLists, 5480 (TemplateParameterList**) TemplateParameterLists.release()); 5481 } 5482 } 5483 else 5484 Invalid = true; 5485 } 5486 5487 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5488 // Add alignment attributes if necessary; these attributes are checked when 5489 // the ASTContext lays out the structure. 5490 // 5491 // It is important for implementing the correct semantics that this 5492 // happen here (in act on tag decl). The #pragma pack stack is 5493 // maintained as a result of parser callbacks which can occur at 5494 // many points during the parsing of a struct declaration (because 5495 // the #pragma tokens are effectively skipped over during the 5496 // parsing of the struct). 5497 AddAlignmentAttributesForRecord(RD); 5498 } 5499 5500 // If this is a specialization of a member class (of a class template), 5501 // check the specialization. 5502 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5503 Invalid = true; 5504 5505 if (Invalid) 5506 New->setInvalidDecl(); 5507 5508 if (Attr) 5509 ProcessDeclAttributeList(S, New, Attr); 5510 5511 // If we're declaring or defining a tag in function prototype scope 5512 // in C, note that this type can only be used within the function. 5513 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5514 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5515 5516 // Set the lexical context. If the tag has a C++ scope specifier, the 5517 // lexical context will be different from the semantic context. 5518 New->setLexicalDeclContext(CurContext); 5519 5520 // Mark this as a friend decl if applicable. 5521 if (TUK == TUK_Friend) 5522 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5523 5524 // Set the access specifier. 5525 if (!Invalid && SearchDC->isRecord()) 5526 SetMemberAccessSpecifier(New, PrevDecl, AS); 5527 5528 if (TUK == TUK_Definition) 5529 New->startDefinition(); 5530 5531 // If this has an identifier, add it to the scope stack. 5532 if (TUK == TUK_Friend) { 5533 // We might be replacing an existing declaration in the lookup tables; 5534 // if so, borrow its access specifier. 5535 if (PrevDecl) 5536 New->setAccess(PrevDecl->getAccess()); 5537 5538 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5539 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5540 if (Name) // can be null along some error paths 5541 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5542 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5543 } else if (Name) { 5544 S = getNonFieldDeclScope(S); 5545 PushOnScopeChains(New, S); 5546 } else { 5547 CurContext->addDecl(New); 5548 } 5549 5550 // If this is the C FILE type, notify the AST context. 5551 if (IdentifierInfo *II = New->getIdentifier()) 5552 if (!New->isInvalidDecl() && 5553 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5554 II->isStr("FILE")) 5555 Context.setFILEDecl(New); 5556 5557 OwnedDecl = true; 5558 return DeclPtrTy::make(New); 5559} 5560 5561void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5562 AdjustDeclIfTemplate(TagD); 5563 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5564 5565 // Enter the tag context. 5566 PushDeclContext(S, Tag); 5567} 5568 5569void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5570 SourceLocation LBraceLoc) { 5571 AdjustDeclIfTemplate(TagD); 5572 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5573 5574 FieldCollector->StartClass(); 5575 5576 if (!Record->getIdentifier()) 5577 return; 5578 5579 // C++ [class]p2: 5580 // [...] The class-name is also inserted into the scope of the 5581 // class itself; this is known as the injected-class-name. For 5582 // purposes of access checking, the injected-class-name is treated 5583 // as if it were a public member name. 5584 CXXRecordDecl *InjectedClassName 5585 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5586 CurContext, Record->getLocation(), 5587 Record->getIdentifier(), 5588 Record->getTagKeywordLoc(), 5589 Record); 5590 InjectedClassName->setImplicit(); 5591 InjectedClassName->setAccess(AS_public); 5592 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5593 InjectedClassName->setDescribedClassTemplate(Template); 5594 PushOnScopeChains(InjectedClassName, S); 5595 assert(InjectedClassName->isInjectedClassName() && 5596 "Broken injected-class-name"); 5597} 5598 5599void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5600 SourceLocation RBraceLoc) { 5601 AdjustDeclIfTemplate(TagD); 5602 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5603 Tag->setRBraceLoc(RBraceLoc); 5604 5605 if (isa<CXXRecordDecl>(Tag)) 5606 FieldCollector->FinishClass(); 5607 5608 // Exit this scope of this tag's definition. 5609 PopDeclContext(); 5610 5611 // Notify the consumer that we've defined a tag. 5612 Consumer.HandleTagDeclDefinition(Tag); 5613} 5614 5615void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5616 AdjustDeclIfTemplate(TagD); 5617 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5618 Tag->setInvalidDecl(); 5619 5620 // We're undoing ActOnTagStartDefinition here, not 5621 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5622 // the FieldCollector. 5623 5624 PopDeclContext(); 5625} 5626 5627// Note that FieldName may be null for anonymous bitfields. 5628bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5629 QualType FieldTy, const Expr *BitWidth, 5630 bool *ZeroWidth) { 5631 // Default to true; that shouldn't confuse checks for emptiness 5632 if (ZeroWidth) 5633 *ZeroWidth = true; 5634 5635 // C99 6.7.2.1p4 - verify the field type. 5636 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5637 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5638 // Handle incomplete types with specific error. 5639 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5640 return true; 5641 if (FieldName) 5642 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5643 << FieldName << FieldTy << BitWidth->getSourceRange(); 5644 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5645 << FieldTy << BitWidth->getSourceRange(); 5646 } 5647 5648 // If the bit-width is type- or value-dependent, don't try to check 5649 // it now. 5650 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5651 return false; 5652 5653 llvm::APSInt Value; 5654 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5655 return true; 5656 5657 if (Value != 0 && ZeroWidth) 5658 *ZeroWidth = false; 5659 5660 // Zero-width bitfield is ok for anonymous field. 5661 if (Value == 0 && FieldName) 5662 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5663 5664 if (Value.isSigned() && Value.isNegative()) { 5665 if (FieldName) 5666 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5667 << FieldName << Value.toString(10); 5668 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5669 << Value.toString(10); 5670 } 5671 5672 if (!FieldTy->isDependentType()) { 5673 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5674 if (Value.getZExtValue() > TypeSize) { 5675 if (!getLangOptions().CPlusPlus) { 5676 if (FieldName) 5677 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5678 << FieldName << (unsigned)Value.getZExtValue() 5679 << (unsigned)TypeSize; 5680 5681 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5682 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5683 } 5684 5685 if (FieldName) 5686 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5687 << FieldName << (unsigned)Value.getZExtValue() 5688 << (unsigned)TypeSize; 5689 else 5690 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5691 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5692 } 5693 } 5694 5695 return false; 5696} 5697 5698/// ActOnField - Each field of a struct/union/class is passed into this in order 5699/// to create a FieldDecl object for it. 5700Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5701 SourceLocation DeclStart, 5702 Declarator &D, ExprTy *BitfieldWidth) { 5703 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5704 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5705 AS_public); 5706 return DeclPtrTy::make(Res); 5707} 5708 5709/// HandleField - Analyze a field of a C struct or a C++ data member. 5710/// 5711FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5712 SourceLocation DeclStart, 5713 Declarator &D, Expr *BitWidth, 5714 AccessSpecifier AS) { 5715 IdentifierInfo *II = D.getIdentifier(); 5716 SourceLocation Loc = DeclStart; 5717 if (II) Loc = D.getIdentifierLoc(); 5718 5719 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5720 QualType T = TInfo->getType(); 5721 if (getLangOptions().CPlusPlus) 5722 CheckExtraCXXDefaultArguments(D); 5723 5724 DiagnoseFunctionSpecifiers(D); 5725 5726 if (D.getDeclSpec().isThreadSpecified()) 5727 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5728 5729 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5730 ForRedeclaration); 5731 5732 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5733 // Maybe we will complain about the shadowed template parameter. 5734 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5735 // Just pretend that we didn't see the previous declaration. 5736 PrevDecl = 0; 5737 } 5738 5739 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5740 PrevDecl = 0; 5741 5742 bool Mutable 5743 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5744 SourceLocation TSSL = D.getSourceRange().getBegin(); 5745 FieldDecl *NewFD 5746 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5747 AS, PrevDecl, &D); 5748 5749 if (NewFD->isInvalidDecl()) 5750 Record->setInvalidDecl(); 5751 5752 if (NewFD->isInvalidDecl() && PrevDecl) { 5753 // Don't introduce NewFD into scope; there's already something 5754 // with the same name in the same scope. 5755 } else if (II) { 5756 PushOnScopeChains(NewFD, S); 5757 } else 5758 Record->addDecl(NewFD); 5759 5760 return NewFD; 5761} 5762 5763/// \brief Build a new FieldDecl and check its well-formedness. 5764/// 5765/// This routine builds a new FieldDecl given the fields name, type, 5766/// record, etc. \p PrevDecl should refer to any previous declaration 5767/// with the same name and in the same scope as the field to be 5768/// created. 5769/// 5770/// \returns a new FieldDecl. 5771/// 5772/// \todo The Declarator argument is a hack. It will be removed once 5773FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5774 TypeSourceInfo *TInfo, 5775 RecordDecl *Record, SourceLocation Loc, 5776 bool Mutable, Expr *BitWidth, 5777 SourceLocation TSSL, 5778 AccessSpecifier AS, NamedDecl *PrevDecl, 5779 Declarator *D) { 5780 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5781 bool InvalidDecl = false; 5782 if (D) InvalidDecl = D->isInvalidType(); 5783 5784 // If we receive a broken type, recover by assuming 'int' and 5785 // marking this declaration as invalid. 5786 if (T.isNull()) { 5787 InvalidDecl = true; 5788 T = Context.IntTy; 5789 } 5790 5791 QualType EltTy = Context.getBaseElementType(T); 5792 if (!EltTy->isDependentType() && 5793 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5794 InvalidDecl = true; 5795 5796 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5797 // than a variably modified type. 5798 if (!InvalidDecl && T->isVariablyModifiedType()) { 5799 bool SizeIsNegative; 5800 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5801 SizeIsNegative); 5802 if (!FixedTy.isNull()) { 5803 Diag(Loc, diag::warn_illegal_constant_array_size); 5804 T = FixedTy; 5805 } else { 5806 if (SizeIsNegative) 5807 Diag(Loc, diag::err_typecheck_negative_array_size); 5808 else 5809 Diag(Loc, diag::err_typecheck_field_variable_size); 5810 InvalidDecl = true; 5811 } 5812 } 5813 5814 // Fields can not have abstract class types 5815 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5816 diag::err_abstract_type_in_decl, 5817 AbstractFieldType)) 5818 InvalidDecl = true; 5819 5820 bool ZeroWidth = false; 5821 // If this is declared as a bit-field, check the bit-field. 5822 if (!InvalidDecl && BitWidth && 5823 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5824 InvalidDecl = true; 5825 DeleteExpr(BitWidth); 5826 BitWidth = 0; 5827 ZeroWidth = false; 5828 } 5829 5830 // Check that 'mutable' is consistent with the type of the declaration. 5831 if (!InvalidDecl && Mutable) { 5832 unsigned DiagID = 0; 5833 if (T->isReferenceType()) 5834 DiagID = diag::err_mutable_reference; 5835 else if (T.isConstQualified()) 5836 DiagID = diag::err_mutable_const; 5837 5838 if (DiagID) { 5839 SourceLocation ErrLoc = Loc; 5840 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 5841 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 5842 Diag(ErrLoc, DiagID); 5843 Mutable = false; 5844 InvalidDecl = true; 5845 } 5846 } 5847 5848 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5849 BitWidth, Mutable); 5850 if (InvalidDecl) 5851 NewFD->setInvalidDecl(); 5852 5853 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5854 Diag(Loc, diag::err_duplicate_member) << II; 5855 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5856 NewFD->setInvalidDecl(); 5857 } 5858 5859 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5860 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5861 5862 if (!T->isPODType()) 5863 CXXRecord->setPOD(false); 5864 if (!ZeroWidth) 5865 CXXRecord->setEmpty(false); 5866 5867 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5868 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5869 if (RDecl->getDefinition()) { 5870 if (!RDecl->hasTrivialConstructor()) 5871 CXXRecord->setHasTrivialConstructor(false); 5872 if (!RDecl->hasTrivialCopyConstructor()) 5873 CXXRecord->setHasTrivialCopyConstructor(false); 5874 if (!RDecl->hasTrivialCopyAssignment()) 5875 CXXRecord->setHasTrivialCopyAssignment(false); 5876 if (!RDecl->hasTrivialDestructor()) 5877 CXXRecord->setHasTrivialDestructor(false); 5878 5879 // C++ 9.5p1: An object of a class with a non-trivial 5880 // constructor, a non-trivial copy constructor, a non-trivial 5881 // destructor, or a non-trivial copy assignment operator 5882 // cannot be a member of a union, nor can an array of such 5883 // objects. 5884 // TODO: C++0x alters this restriction significantly. 5885 if (Record->isUnion()) { 5886 // We check for copy constructors before constructors 5887 // because otherwise we'll never get complaints about 5888 // copy constructors. 5889 5890 CXXSpecialMember member = CXXInvalid; 5891 if (!RDecl->hasTrivialCopyConstructor()) 5892 member = CXXCopyConstructor; 5893 else if (!RDecl->hasTrivialConstructor()) 5894 member = CXXConstructor; 5895 else if (!RDecl->hasTrivialCopyAssignment()) 5896 member = CXXCopyAssignment; 5897 else if (!RDecl->hasTrivialDestructor()) 5898 member = CXXDestructor; 5899 5900 if (member != CXXInvalid) { 5901 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5902 DiagnoseNontrivial(RT, member); 5903 NewFD->setInvalidDecl(); 5904 } 5905 } 5906 } 5907 } 5908 } 5909 5910 // FIXME: We need to pass in the attributes given an AST 5911 // representation, not a parser representation. 5912 if (D) 5913 // FIXME: What to pass instead of TUScope? 5914 ProcessDeclAttributes(TUScope, NewFD, *D); 5915 5916 if (T.isObjCGCWeak()) 5917 Diag(Loc, diag::warn_attribute_weak_on_field); 5918 5919 NewFD->setAccess(AS); 5920 5921 // C++ [dcl.init.aggr]p1: 5922 // An aggregate is an array or a class (clause 9) with [...] no 5923 // private or protected non-static data members (clause 11). 5924 // A POD must be an aggregate. 5925 if (getLangOptions().CPlusPlus && 5926 (AS == AS_private || AS == AS_protected)) { 5927 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5928 CXXRecord->setAggregate(false); 5929 CXXRecord->setPOD(false); 5930 } 5931 5932 return NewFD; 5933} 5934 5935/// DiagnoseNontrivial - Given that a class has a non-trivial 5936/// special member, figure out why. 5937void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5938 QualType QT(T, 0U); 5939 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5940 5941 // Check whether the member was user-declared. 5942 switch (member) { 5943 case CXXInvalid: 5944 break; 5945 5946 case CXXConstructor: 5947 if (RD->hasUserDeclaredConstructor()) { 5948 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5949 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5950 const FunctionDecl *body = 0; 5951 ci->hasBody(body); 5952 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5953 SourceLocation CtorLoc = ci->getLocation(); 5954 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5955 return; 5956 } 5957 } 5958 5959 assert(0 && "found no user-declared constructors"); 5960 return; 5961 } 5962 break; 5963 5964 case CXXCopyConstructor: 5965 if (RD->hasUserDeclaredCopyConstructor()) { 5966 SourceLocation CtorLoc = 5967 RD->getCopyConstructor(Context, 0)->getLocation(); 5968 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5969 return; 5970 } 5971 break; 5972 5973 case CXXCopyAssignment: 5974 if (RD->hasUserDeclaredCopyAssignment()) { 5975 // FIXME: this should use the location of the copy 5976 // assignment, not the type. 5977 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5978 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5979 return; 5980 } 5981 break; 5982 5983 case CXXDestructor: 5984 if (RD->hasUserDeclaredDestructor()) { 5985 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 5986 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5987 return; 5988 } 5989 break; 5990 } 5991 5992 typedef CXXRecordDecl::base_class_iterator base_iter; 5993 5994 // Virtual bases and members inhibit trivial copying/construction, 5995 // but not trivial destruction. 5996 if (member != CXXDestructor) { 5997 // Check for virtual bases. vbases includes indirect virtual bases, 5998 // so we just iterate through the direct bases. 5999 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6000 if (bi->isVirtual()) { 6001 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6002 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6003 return; 6004 } 6005 6006 // Check for virtual methods. 6007 typedef CXXRecordDecl::method_iterator meth_iter; 6008 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6009 ++mi) { 6010 if (mi->isVirtual()) { 6011 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6012 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6013 return; 6014 } 6015 } 6016 } 6017 6018 bool (CXXRecordDecl::*hasTrivial)() const; 6019 switch (member) { 6020 case CXXConstructor: 6021 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6022 case CXXCopyConstructor: 6023 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6024 case CXXCopyAssignment: 6025 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6026 case CXXDestructor: 6027 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6028 default: 6029 assert(0 && "unexpected special member"); return; 6030 } 6031 6032 // Check for nontrivial bases (and recurse). 6033 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6034 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6035 assert(BaseRT && "Don't know how to handle dependent bases"); 6036 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6037 if (!(BaseRecTy->*hasTrivial)()) { 6038 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6039 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6040 DiagnoseNontrivial(BaseRT, member); 6041 return; 6042 } 6043 } 6044 6045 // Check for nontrivial members (and recurse). 6046 typedef RecordDecl::field_iterator field_iter; 6047 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6048 ++fi) { 6049 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6050 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6051 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6052 6053 if (!(EltRD->*hasTrivial)()) { 6054 SourceLocation FLoc = (*fi)->getLocation(); 6055 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6056 DiagnoseNontrivial(EltRT, member); 6057 return; 6058 } 6059 } 6060 } 6061 6062 assert(0 && "found no explanation for non-trivial member"); 6063} 6064 6065/// TranslateIvarVisibility - Translate visibility from a token ID to an 6066/// AST enum value. 6067static ObjCIvarDecl::AccessControl 6068TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6069 switch (ivarVisibility) { 6070 default: assert(0 && "Unknown visitibility kind"); 6071 case tok::objc_private: return ObjCIvarDecl::Private; 6072 case tok::objc_public: return ObjCIvarDecl::Public; 6073 case tok::objc_protected: return ObjCIvarDecl::Protected; 6074 case tok::objc_package: return ObjCIvarDecl::Package; 6075 } 6076} 6077 6078/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6079/// in order to create an IvarDecl object for it. 6080Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 6081 SourceLocation DeclStart, 6082 DeclPtrTy IntfDecl, 6083 Declarator &D, ExprTy *BitfieldWidth, 6084 tok::ObjCKeywordKind Visibility) { 6085 6086 IdentifierInfo *II = D.getIdentifier(); 6087 Expr *BitWidth = (Expr*)BitfieldWidth; 6088 SourceLocation Loc = DeclStart; 6089 if (II) Loc = D.getIdentifierLoc(); 6090 6091 // FIXME: Unnamed fields can be handled in various different ways, for 6092 // example, unnamed unions inject all members into the struct namespace! 6093 6094 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6095 QualType T = TInfo->getType(); 6096 6097 if (BitWidth) { 6098 // 6.7.2.1p3, 6.7.2.1p4 6099 if (VerifyBitField(Loc, II, T, BitWidth)) { 6100 D.setInvalidType(); 6101 DeleteExpr(BitWidth); 6102 BitWidth = 0; 6103 } 6104 } else { 6105 // Not a bitfield. 6106 6107 // validate II. 6108 6109 } 6110 if (T->isReferenceType()) { 6111 Diag(Loc, diag::err_ivar_reference_type); 6112 D.setInvalidType(); 6113 } 6114 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6115 // than a variably modified type. 6116 else if (T->isVariablyModifiedType()) { 6117 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6118 D.setInvalidType(); 6119 } 6120 6121 // Get the visibility (access control) for this ivar. 6122 ObjCIvarDecl::AccessControl ac = 6123 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6124 : ObjCIvarDecl::None; 6125 // Must set ivar's DeclContext to its enclosing interface. 6126 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 6127 ObjCContainerDecl *EnclosingContext; 6128 if (ObjCImplementationDecl *IMPDecl = 6129 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6130 // Case of ivar declared in an implementation. Context is that of its class. 6131 EnclosingContext = IMPDecl->getClassInterface(); 6132 assert(EnclosingContext && "Implementation has no class interface!"); 6133 } else { 6134 if (ObjCCategoryDecl *CDecl = 6135 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6136 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6137 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6138 return DeclPtrTy(); 6139 } 6140 } 6141 EnclosingContext = EnclosingDecl; 6142 } 6143 6144 // Construct the decl. 6145 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6146 EnclosingContext, Loc, II, T, 6147 TInfo, ac, (Expr *)BitfieldWidth); 6148 6149 if (II) { 6150 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6151 ForRedeclaration); 6152 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6153 && !isa<TagDecl>(PrevDecl)) { 6154 Diag(Loc, diag::err_duplicate_member) << II; 6155 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6156 NewID->setInvalidDecl(); 6157 } 6158 } 6159 6160 // Process attributes attached to the ivar. 6161 ProcessDeclAttributes(S, NewID, D); 6162 6163 if (D.isInvalidType()) 6164 NewID->setInvalidDecl(); 6165 6166 if (II) { 6167 // FIXME: When interfaces are DeclContexts, we'll need to add 6168 // these to the interface. 6169 S->AddDecl(DeclPtrTy::make(NewID)); 6170 IdResolver.AddDecl(NewID); 6171 } 6172 6173 return DeclPtrTy::make(NewID); 6174} 6175 6176void Sema::ActOnFields(Scope* S, 6177 SourceLocation RecLoc, DeclPtrTy RecDecl, 6178 DeclPtrTy *Fields, unsigned NumFields, 6179 SourceLocation LBrac, SourceLocation RBrac, 6180 AttributeList *Attr) { 6181 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 6182 assert(EnclosingDecl && "missing record or interface decl"); 6183 6184 // If the decl this is being inserted into is invalid, then it may be a 6185 // redeclaration or some other bogus case. Don't try to add fields to it. 6186 if (EnclosingDecl->isInvalidDecl()) { 6187 // FIXME: Deallocate fields? 6188 return; 6189 } 6190 6191 6192 // Verify that all the fields are okay. 6193 unsigned NumNamedMembers = 0; 6194 llvm::SmallVector<FieldDecl*, 32> RecFields; 6195 6196 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6197 for (unsigned i = 0; i != NumFields; ++i) { 6198 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 6199 6200 // Get the type for the field. 6201 Type *FDTy = FD->getType().getTypePtr(); 6202 6203 if (!FD->isAnonymousStructOrUnion()) { 6204 // Remember all fields written by the user. 6205 RecFields.push_back(FD); 6206 } 6207 6208 // If the field is already invalid for some reason, don't emit more 6209 // diagnostics about it. 6210 if (FD->isInvalidDecl()) { 6211 EnclosingDecl->setInvalidDecl(); 6212 continue; 6213 } 6214 6215 // C99 6.7.2.1p2: 6216 // A structure or union shall not contain a member with 6217 // incomplete or function type (hence, a structure shall not 6218 // contain an instance of itself, but may contain a pointer to 6219 // an instance of itself), except that the last member of a 6220 // structure with more than one named member may have incomplete 6221 // array type; such a structure (and any union containing, 6222 // possibly recursively, a member that is such a structure) 6223 // shall not be a member of a structure or an element of an 6224 // array. 6225 if (FDTy->isFunctionType()) { 6226 // Field declared as a function. 6227 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6228 << FD->getDeclName(); 6229 FD->setInvalidDecl(); 6230 EnclosingDecl->setInvalidDecl(); 6231 continue; 6232 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6233 Record && Record->isStruct()) { 6234 // Flexible array member. 6235 if (NumNamedMembers < 1) { 6236 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6237 << FD->getDeclName(); 6238 FD->setInvalidDecl(); 6239 EnclosingDecl->setInvalidDecl(); 6240 continue; 6241 } 6242 if (!FD->getType()->isDependentType() && 6243 !Context.getBaseElementType(FD->getType())->isPODType()) { 6244 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6245 << FD->getDeclName() << FD->getType(); 6246 FD->setInvalidDecl(); 6247 EnclosingDecl->setInvalidDecl(); 6248 continue; 6249 } 6250 6251 // Okay, we have a legal flexible array member at the end of the struct. 6252 if (Record) 6253 Record->setHasFlexibleArrayMember(true); 6254 } else if (!FDTy->isDependentType() && 6255 RequireCompleteType(FD->getLocation(), FD->getType(), 6256 diag::err_field_incomplete)) { 6257 // Incomplete type 6258 FD->setInvalidDecl(); 6259 EnclosingDecl->setInvalidDecl(); 6260 continue; 6261 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6262 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6263 // If this is a member of a union, then entire union becomes "flexible". 6264 if (Record && Record->isUnion()) { 6265 Record->setHasFlexibleArrayMember(true); 6266 } else { 6267 // If this is a struct/class and this is not the last element, reject 6268 // it. Note that GCC supports variable sized arrays in the middle of 6269 // structures. 6270 if (i != NumFields-1) 6271 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6272 << FD->getDeclName() << FD->getType(); 6273 else { 6274 // We support flexible arrays at the end of structs in 6275 // other structs as an extension. 6276 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6277 << FD->getDeclName(); 6278 if (Record) 6279 Record->setHasFlexibleArrayMember(true); 6280 } 6281 } 6282 } 6283 if (Record && FDTTy->getDecl()->hasObjectMember()) 6284 Record->setHasObjectMember(true); 6285 } else if (FDTy->isObjCObjectType()) { 6286 /// A field cannot be an Objective-c object 6287 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6288 FD->setInvalidDecl(); 6289 EnclosingDecl->setInvalidDecl(); 6290 continue; 6291 } else if (getLangOptions().ObjC1 && 6292 getLangOptions().getGCMode() != LangOptions::NonGC && 6293 Record && 6294 (FD->getType()->isObjCObjectPointerType() || 6295 FD->getType().isObjCGCStrong())) 6296 Record->setHasObjectMember(true); 6297 else if (Context.getAsArrayType(FD->getType())) { 6298 QualType BaseType = Context.getBaseElementType(FD->getType()); 6299 if (Record && BaseType->isRecordType() && 6300 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6301 Record->setHasObjectMember(true); 6302 } 6303 // Keep track of the number of named members. 6304 if (FD->getIdentifier()) 6305 ++NumNamedMembers; 6306 } 6307 6308 // Okay, we successfully defined 'Record'. 6309 if (Record) { 6310 Record->completeDefinition(); 6311 } else { 6312 ObjCIvarDecl **ClsFields = 6313 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6314 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6315 ID->setLocEnd(RBrac); 6316 // Add ivar's to class's DeclContext. 6317 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6318 ClsFields[i]->setLexicalDeclContext(ID); 6319 ID->addDecl(ClsFields[i]); 6320 } 6321 // Must enforce the rule that ivars in the base classes may not be 6322 // duplicates. 6323 if (ID->getSuperClass()) 6324 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6325 } else if (ObjCImplementationDecl *IMPDecl = 6326 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6327 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6328 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6329 // Ivar declared in @implementation never belongs to the implementation. 6330 // Only it is in implementation's lexical context. 6331 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6332 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6333 } else if (ObjCCategoryDecl *CDecl = 6334 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6335 // case of ivars in class extension; all other cases have been 6336 // reported as errors elsewhere. 6337 // FIXME. Class extension does not have a LocEnd field. 6338 // CDecl->setLocEnd(RBrac); 6339 // Add ivar's to class extension's DeclContext. 6340 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6341 ClsFields[i]->setLexicalDeclContext(CDecl); 6342 CDecl->addDecl(ClsFields[i]); 6343 } 6344 } 6345 } 6346 6347 if (Attr) 6348 ProcessDeclAttributeList(S, Record, Attr); 6349} 6350 6351/// \brief Determine whether the given integral value is representable within 6352/// the given type T. 6353static bool isRepresentableIntegerValue(ASTContext &Context, 6354 llvm::APSInt &Value, 6355 QualType T) { 6356 assert(T->isIntegralType(Context) && "Integral type required!"); 6357 unsigned BitWidth = Context.getIntWidth(T); 6358 6359 if (Value.isUnsigned() || Value.isNonNegative()) 6360 return Value.getActiveBits() < BitWidth; 6361 6362 return Value.getMinSignedBits() <= BitWidth; 6363} 6364 6365// \brief Given an integral type, return the next larger integral type 6366// (or a NULL type of no such type exists). 6367static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6368 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6369 // enum checking below. 6370 assert(T->isIntegralType(Context) && "Integral type required!"); 6371 const unsigned NumTypes = 4; 6372 QualType SignedIntegralTypes[NumTypes] = { 6373 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6374 }; 6375 QualType UnsignedIntegralTypes[NumTypes] = { 6376 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6377 Context.UnsignedLongLongTy 6378 }; 6379 6380 unsigned BitWidth = Context.getTypeSize(T); 6381 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6382 : UnsignedIntegralTypes; 6383 for (unsigned I = 0; I != NumTypes; ++I) 6384 if (Context.getTypeSize(Types[I]) > BitWidth) 6385 return Types[I]; 6386 6387 return QualType(); 6388} 6389 6390EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6391 EnumConstantDecl *LastEnumConst, 6392 SourceLocation IdLoc, 6393 IdentifierInfo *Id, 6394 ExprArg val) { 6395 Expr *Val = (Expr *)val.get(); 6396 6397 unsigned IntWidth = Context.Target.getIntWidth(); 6398 llvm::APSInt EnumVal(IntWidth); 6399 QualType EltTy; 6400 if (Val) { 6401 if (Enum->isDependentType() || Val->isTypeDependent()) 6402 EltTy = Context.DependentTy; 6403 else { 6404 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6405 SourceLocation ExpLoc; 6406 if (!Val->isValueDependent() && 6407 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6408 Val = 0; 6409 } else { 6410 if (!getLangOptions().CPlusPlus) { 6411 // C99 6.7.2.2p2: 6412 // The expression that defines the value of an enumeration constant 6413 // shall be an integer constant expression that has a value 6414 // representable as an int. 6415 6416 // Complain if the value is not representable in an int. 6417 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6418 Diag(IdLoc, diag::ext_enum_value_not_int) 6419 << EnumVal.toString(10) << Val->getSourceRange() 6420 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6421 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6422 // Force the type of the expression to 'int'. 6423 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6424 6425 if (Val != val.get()) { 6426 val.release(); 6427 val = Val; 6428 } 6429 } 6430 } 6431 6432 // C++0x [dcl.enum]p5: 6433 // If the underlying type is not fixed, the type of each enumerator 6434 // is the type of its initializing value: 6435 // - If an initializer is specified for an enumerator, the 6436 // initializing value has the same type as the expression. 6437 EltTy = Val->getType(); 6438 } 6439 } 6440 } 6441 6442 if (!Val) { 6443 if (Enum->isDependentType()) 6444 EltTy = Context.DependentTy; 6445 else if (!LastEnumConst) { 6446 // C++0x [dcl.enum]p5: 6447 // If the underlying type is not fixed, the type of each enumerator 6448 // is the type of its initializing value: 6449 // - If no initializer is specified for the first enumerator, the 6450 // initializing value has an unspecified integral type. 6451 // 6452 // GCC uses 'int' for its unspecified integral type, as does 6453 // C99 6.7.2.2p3. 6454 EltTy = Context.IntTy; 6455 } else { 6456 // Assign the last value + 1. 6457 EnumVal = LastEnumConst->getInitVal(); 6458 ++EnumVal; 6459 EltTy = LastEnumConst->getType(); 6460 6461 // Check for overflow on increment. 6462 if (EnumVal < LastEnumConst->getInitVal()) { 6463 // C++0x [dcl.enum]p5: 6464 // If the underlying type is not fixed, the type of each enumerator 6465 // is the type of its initializing value: 6466 // 6467 // - Otherwise the type of the initializing value is the same as 6468 // the type of the initializing value of the preceding enumerator 6469 // unless the incremented value is not representable in that type, 6470 // in which case the type is an unspecified integral type 6471 // sufficient to contain the incremented value. If no such type 6472 // exists, the program is ill-formed. 6473 QualType T = getNextLargerIntegralType(Context, EltTy); 6474 if (T.isNull()) { 6475 // There is no integral type larger enough to represent this 6476 // value. Complain, then allow the value to wrap around. 6477 EnumVal = LastEnumConst->getInitVal(); 6478 EnumVal.zext(EnumVal.getBitWidth() * 2); 6479 Diag(IdLoc, diag::warn_enumerator_too_large) 6480 << EnumVal.toString(10); 6481 } else { 6482 EltTy = T; 6483 } 6484 6485 // Retrieve the last enumerator's value, extent that type to the 6486 // type that is supposed to be large enough to represent the incremented 6487 // value, then increment. 6488 EnumVal = LastEnumConst->getInitVal(); 6489 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6490 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6491 ++EnumVal; 6492 6493 // If we're not in C++, diagnose the overflow of enumerator values, 6494 // which in C99 means that the enumerator value is not representable in 6495 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6496 // permits enumerator values that are representable in some larger 6497 // integral type. 6498 if (!getLangOptions().CPlusPlus && !T.isNull()) 6499 Diag(IdLoc, diag::warn_enum_value_overflow); 6500 } else if (!getLangOptions().CPlusPlus && 6501 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6502 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6503 Diag(IdLoc, diag::ext_enum_value_not_int) 6504 << EnumVal.toString(10) << 1; 6505 } 6506 } 6507 } 6508 6509 if (!EltTy->isDependentType()) { 6510 // Make the enumerator value match the signedness and size of the 6511 // enumerator's type. 6512 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6513 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6514 } 6515 6516 val.release(); 6517 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6518 Val, EnumVal); 6519} 6520 6521 6522Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6523 DeclPtrTy lastEnumConst, 6524 SourceLocation IdLoc, 6525 IdentifierInfo *Id, 6526 SourceLocation EqualLoc, ExprTy *val) { 6527 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6528 EnumConstantDecl *LastEnumConst = 6529 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6530 Expr *Val = static_cast<Expr*>(val); 6531 6532 // The scope passed in may not be a decl scope. Zip up the scope tree until 6533 // we find one that is. 6534 S = getNonFieldDeclScope(S); 6535 6536 // Verify that there isn't already something declared with this name in this 6537 // scope. 6538 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6539 ForRedeclaration); 6540 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6541 // Maybe we will complain about the shadowed template parameter. 6542 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6543 // Just pretend that we didn't see the previous declaration. 6544 PrevDecl = 0; 6545 } 6546 6547 if (PrevDecl) { 6548 // When in C++, we may get a TagDecl with the same name; in this case the 6549 // enum constant will 'hide' the tag. 6550 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6551 "Received TagDecl when not in C++!"); 6552 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6553 if (isa<EnumConstantDecl>(PrevDecl)) 6554 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6555 else 6556 Diag(IdLoc, diag::err_redefinition) << Id; 6557 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6558 if (Val) Val->Destroy(Context); 6559 return DeclPtrTy(); 6560 } 6561 } 6562 6563 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6564 IdLoc, Id, Owned(Val)); 6565 6566 // Register this decl in the current scope stack. 6567 if (New) { 6568 New->setAccess(TheEnumDecl->getAccess()); 6569 PushOnScopeChains(New, S); 6570 } 6571 6572 return DeclPtrTy::make(New); 6573} 6574 6575void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6576 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6577 DeclPtrTy *Elements, unsigned NumElements, 6578 Scope *S, AttributeList *Attr) { 6579 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6580 QualType EnumType = Context.getTypeDeclType(Enum); 6581 6582 if (Attr) 6583 ProcessDeclAttributeList(S, Enum, Attr); 6584 6585 if (Enum->isDependentType()) { 6586 for (unsigned i = 0; i != NumElements; ++i) { 6587 EnumConstantDecl *ECD = 6588 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6589 if (!ECD) continue; 6590 6591 ECD->setType(EnumType); 6592 } 6593 6594 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6595 return; 6596 } 6597 6598 // TODO: If the result value doesn't fit in an int, it must be a long or long 6599 // long value. ISO C does not support this, but GCC does as an extension, 6600 // emit a warning. 6601 unsigned IntWidth = Context.Target.getIntWidth(); 6602 unsigned CharWidth = Context.Target.getCharWidth(); 6603 unsigned ShortWidth = Context.Target.getShortWidth(); 6604 6605 // Verify that all the values are okay, compute the size of the values, and 6606 // reverse the list. 6607 unsigned NumNegativeBits = 0; 6608 unsigned NumPositiveBits = 0; 6609 6610 // Keep track of whether all elements have type int. 6611 bool AllElementsInt = true; 6612 6613 for (unsigned i = 0; i != NumElements; ++i) { 6614 EnumConstantDecl *ECD = 6615 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6616 if (!ECD) continue; // Already issued a diagnostic. 6617 6618 const llvm::APSInt &InitVal = ECD->getInitVal(); 6619 6620 // Keep track of the size of positive and negative values. 6621 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6622 NumPositiveBits = std::max(NumPositiveBits, 6623 (unsigned)InitVal.getActiveBits()); 6624 else 6625 NumNegativeBits = std::max(NumNegativeBits, 6626 (unsigned)InitVal.getMinSignedBits()); 6627 6628 // Keep track of whether every enum element has type int (very commmon). 6629 if (AllElementsInt) 6630 AllElementsInt = ECD->getType() == Context.IntTy; 6631 } 6632 6633 // Figure out the type that should be used for this enum. 6634 // FIXME: Support -fshort-enums. 6635 QualType BestType; 6636 unsigned BestWidth; 6637 6638 // C++0x N3000 [conv.prom]p3: 6639 // An rvalue of an unscoped enumeration type whose underlying 6640 // type is not fixed can be converted to an rvalue of the first 6641 // of the following types that can represent all the values of 6642 // the enumeration: int, unsigned int, long int, unsigned long 6643 // int, long long int, or unsigned long long int. 6644 // C99 6.4.4.3p2: 6645 // An identifier declared as an enumeration constant has type int. 6646 // The C99 rule is modified by a gcc extension 6647 QualType BestPromotionType; 6648 6649 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6650 6651 if (NumNegativeBits) { 6652 // If there is a negative value, figure out the smallest integer type (of 6653 // int/long/longlong) that fits. 6654 // If it's packed, check also if it fits a char or a short. 6655 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6656 BestType = Context.SignedCharTy; 6657 BestWidth = CharWidth; 6658 } else if (Packed && NumNegativeBits <= ShortWidth && 6659 NumPositiveBits < ShortWidth) { 6660 BestType = Context.ShortTy; 6661 BestWidth = ShortWidth; 6662 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6663 BestType = Context.IntTy; 6664 BestWidth = IntWidth; 6665 } else { 6666 BestWidth = Context.Target.getLongWidth(); 6667 6668 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6669 BestType = Context.LongTy; 6670 } else { 6671 BestWidth = Context.Target.getLongLongWidth(); 6672 6673 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6674 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6675 BestType = Context.LongLongTy; 6676 } 6677 } 6678 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6679 } else { 6680 // If there is no negative value, figure out the smallest type that fits 6681 // all of the enumerator values. 6682 // If it's packed, check also if it fits a char or a short. 6683 if (Packed && NumPositiveBits <= CharWidth) { 6684 BestType = Context.UnsignedCharTy; 6685 BestPromotionType = Context.IntTy; 6686 BestWidth = CharWidth; 6687 } else if (Packed && NumPositiveBits <= ShortWidth) { 6688 BestType = Context.UnsignedShortTy; 6689 BestPromotionType = Context.IntTy; 6690 BestWidth = ShortWidth; 6691 } else if (NumPositiveBits <= IntWidth) { 6692 BestType = Context.UnsignedIntTy; 6693 BestWidth = IntWidth; 6694 BestPromotionType 6695 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6696 ? Context.UnsignedIntTy : Context.IntTy; 6697 } else if (NumPositiveBits <= 6698 (BestWidth = Context.Target.getLongWidth())) { 6699 BestType = Context.UnsignedLongTy; 6700 BestPromotionType 6701 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6702 ? Context.UnsignedLongTy : Context.LongTy; 6703 } else { 6704 BestWidth = Context.Target.getLongLongWidth(); 6705 assert(NumPositiveBits <= BestWidth && 6706 "How could an initializer get larger than ULL?"); 6707 BestType = Context.UnsignedLongLongTy; 6708 BestPromotionType 6709 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6710 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6711 } 6712 } 6713 6714 // Loop over all of the enumerator constants, changing their types to match 6715 // the type of the enum if needed. 6716 for (unsigned i = 0; i != NumElements; ++i) { 6717 EnumConstantDecl *ECD = 6718 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6719 if (!ECD) continue; // Already issued a diagnostic. 6720 6721 // Standard C says the enumerators have int type, but we allow, as an 6722 // extension, the enumerators to be larger than int size. If each 6723 // enumerator value fits in an int, type it as an int, otherwise type it the 6724 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6725 // that X has type 'int', not 'unsigned'. 6726 6727 // Determine whether the value fits into an int. 6728 llvm::APSInt InitVal = ECD->getInitVal(); 6729 6730 // If it fits into an integer type, force it. Otherwise force it to match 6731 // the enum decl type. 6732 QualType NewTy; 6733 unsigned NewWidth; 6734 bool NewSign; 6735 if (!getLangOptions().CPlusPlus && 6736 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6737 NewTy = Context.IntTy; 6738 NewWidth = IntWidth; 6739 NewSign = true; 6740 } else if (ECD->getType() == BestType) { 6741 // Already the right type! 6742 if (getLangOptions().CPlusPlus) 6743 // C++ [dcl.enum]p4: Following the closing brace of an 6744 // enum-specifier, each enumerator has the type of its 6745 // enumeration. 6746 ECD->setType(EnumType); 6747 continue; 6748 } else { 6749 NewTy = BestType; 6750 NewWidth = BestWidth; 6751 NewSign = BestType->isSignedIntegerType(); 6752 } 6753 6754 // Adjust the APSInt value. 6755 InitVal.extOrTrunc(NewWidth); 6756 InitVal.setIsSigned(NewSign); 6757 ECD->setInitVal(InitVal); 6758 6759 // Adjust the Expr initializer and type. 6760 if (ECD->getInitExpr()) 6761 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6762 CastExpr::CK_IntegralCast, 6763 ECD->getInitExpr(), 6764 CXXBaseSpecifierArray(), 6765 /*isLvalue=*/false)); 6766 if (getLangOptions().CPlusPlus) 6767 // C++ [dcl.enum]p4: Following the closing brace of an 6768 // enum-specifier, each enumerator has the type of its 6769 // enumeration. 6770 ECD->setType(EnumType); 6771 else 6772 ECD->setType(NewTy); 6773 } 6774 6775 Enum->completeDefinition(BestType, BestPromotionType, 6776 NumPositiveBits, NumNegativeBits); 6777} 6778 6779Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6780 ExprArg expr) { 6781 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6782 6783 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6784 Loc, AsmString); 6785 CurContext->addDecl(New); 6786 return DeclPtrTy::make(New); 6787} 6788 6789void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6790 SourceLocation PragmaLoc, 6791 SourceLocation NameLoc) { 6792 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6793 6794 if (PrevDecl) { 6795 PrevDecl->addAttr(::new (Context) WeakAttr()); 6796 } else { 6797 (void)WeakUndeclaredIdentifiers.insert( 6798 std::pair<IdentifierInfo*,WeakInfo> 6799 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6800 } 6801} 6802 6803void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6804 IdentifierInfo* AliasName, 6805 SourceLocation PragmaLoc, 6806 SourceLocation NameLoc, 6807 SourceLocation AliasNameLoc) { 6808 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6809 LookupOrdinaryName); 6810 WeakInfo W = WeakInfo(Name, NameLoc); 6811 6812 if (PrevDecl) { 6813 if (!PrevDecl->hasAttr<AliasAttr>()) 6814 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6815 DeclApplyPragmaWeak(TUScope, ND, W); 6816 } else { 6817 (void)WeakUndeclaredIdentifiers.insert( 6818 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6819 } 6820} 6821