SemaDecl.cpp revision 447234dd459a00a5ed9b7c3e066162cd7a75bf2d
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 assert(CurContext && "Popped translation unit!"); 364} 365 366/// EnterDeclaratorContext - Used when we must lookup names in the context 367/// of a declarator's nested name specifier. 368/// 369void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 370 // C++0x [basic.lookup.unqual]p13: 371 // A name used in the definition of a static data member of class 372 // X (after the qualified-id of the static member) is looked up as 373 // if the name was used in a member function of X. 374 // C++0x [basic.lookup.unqual]p14: 375 // If a variable member of a namespace is defined outside of the 376 // scope of its namespace then any name used in the definition of 377 // the variable member (after the declarator-id) is looked up as 378 // if the definition of the variable member occurred in its 379 // namespace. 380 // Both of these imply that we should push a scope whose context 381 // is the semantic context of the declaration. We can't use 382 // PushDeclContext here because that context is not necessarily 383 // lexically contained in the current context. Fortunately, 384 // the containing scope should have the appropriate information. 385 386 assert(!S->getEntity() && "scope already has entity"); 387 388#ifndef NDEBUG 389 Scope *Ancestor = S->getParent(); 390 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 391 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 392#endif 393 394 CurContext = DC; 395 S->setEntity(DC); 396} 397 398void Sema::ExitDeclaratorContext(Scope *S) { 399 assert(S->getEntity() == CurContext && "Context imbalance!"); 400 401 // Switch back to the lexical context. The safety of this is 402 // enforced by an assert in EnterDeclaratorContext. 403 Scope *Ancestor = S->getParent(); 404 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 405 CurContext = (DeclContext*) Ancestor->getEntity(); 406 407 // We don't need to do anything with the scope, which is going to 408 // disappear. 409} 410 411/// \brief Determine whether we allow overloading of the function 412/// PrevDecl with another declaration. 413/// 414/// This routine determines whether overloading is possible, not 415/// whether some new function is actually an overload. It will return 416/// true in C++ (where we can always provide overloads) or, as an 417/// extension, in C when the previous function is already an 418/// overloaded function declaration or has the "overloadable" 419/// attribute. 420static bool AllowOverloadingOfFunction(LookupResult &Previous, 421 ASTContext &Context) { 422 if (Context.getLangOptions().CPlusPlus) 423 return true; 424 425 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 426 return true; 427 428 return (Previous.getResultKind() == LookupResult::Found 429 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 430} 431 432/// Add this decl to the scope shadowed decl chains. 433void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 434 // Move up the scope chain until we find the nearest enclosing 435 // non-transparent context. The declaration will be introduced into this 436 // scope. 437 while (S->getEntity() && 438 ((DeclContext *)S->getEntity())->isTransparentContext()) 439 S = S->getParent(); 440 441 // Add scoped declarations into their context, so that they can be 442 // found later. Declarations without a context won't be inserted 443 // into any context. 444 if (AddToContext) 445 CurContext->addDecl(D); 446 447 // Out-of-line definitions shouldn't be pushed into scope in C++. 448 // Out-of-line variable and function definitions shouldn't even in C. 449 if ((getLangOptions().CPlusPlus || isa<VarDecl>(D) || isa<FunctionDecl>(D)) && 450 D->isOutOfLine()) 451 return; 452 453 // Template instantiations should also not be pushed into scope. 454 if (isa<FunctionDecl>(D) && 455 cast<FunctionDecl>(D)->isFunctionTemplateSpecialization()) 456 return; 457 458 // If this replaces anything in the current scope, 459 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 460 IEnd = IdResolver.end(); 461 for (; I != IEnd; ++I) { 462 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 463 S->RemoveDecl(DeclPtrTy::make(*I)); 464 IdResolver.RemoveDecl(*I); 465 466 // Should only need to replace one decl. 467 break; 468 } 469 } 470 471 S->AddDecl(DeclPtrTy::make(D)); 472 IdResolver.AddDecl(D); 473} 474 475bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 476 return IdResolver.isDeclInScope(D, Ctx, Context, S); 477} 478 479static bool isOutOfScopePreviousDeclaration(NamedDecl *, 480 DeclContext*, 481 ASTContext&); 482 483/// Filters out lookup results that don't fall within the given scope 484/// as determined by isDeclInScope. 485static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 486 DeclContext *Ctx, Scope *S, 487 bool ConsiderLinkage) { 488 LookupResult::Filter F = R.makeFilter(); 489 while (F.hasNext()) { 490 NamedDecl *D = F.next(); 491 492 if (SemaRef.isDeclInScope(D, Ctx, S)) 493 continue; 494 495 if (ConsiderLinkage && 496 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 497 continue; 498 499 F.erase(); 500 } 501 502 F.done(); 503} 504 505static bool isUsingDecl(NamedDecl *D) { 506 return isa<UsingShadowDecl>(D) || 507 isa<UnresolvedUsingTypenameDecl>(D) || 508 isa<UnresolvedUsingValueDecl>(D); 509} 510 511/// Removes using shadow declarations from the lookup results. 512static void RemoveUsingDecls(LookupResult &R) { 513 LookupResult::Filter F = R.makeFilter(); 514 while (F.hasNext()) 515 if (isUsingDecl(F.next())) 516 F.erase(); 517 518 F.done(); 519} 520 521static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 522 if (D->isInvalidDecl()) 523 return false; 524 525 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 526 return false; 527 528 // White-list anything that isn't a local variable. 529 if (!isa<VarDecl>(D) || isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 530 !D->getDeclContext()->isFunctionOrMethod()) 531 return false; 532 533 // Types of valid local variables should be complete, so this should succeed. 534 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 535 536 // White-list anything with an __attribute__((unused)) type. 537 QualType Ty = VD->getType(); 538 539 // Only look at the outermost level of typedef. 540 if (const TypedefType *TT = dyn_cast<TypedefType>(Ty)) { 541 if (TT->getDecl()->hasAttr<UnusedAttr>()) 542 return false; 543 } 544 545 // If we failed to complete the type for some reason, or if the type is 546 // dependent, don't diagnose the variable. 547 if (Ty->isIncompleteType() || Ty->isDependentType()) 548 return false; 549 550 if (const TagType *TT = Ty->getAs<TagType>()) { 551 const TagDecl *Tag = TT->getDecl(); 552 if (Tag->hasAttr<UnusedAttr>()) 553 return false; 554 555 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Tag)) { 556 // FIXME: Checking for the presence of a user-declared constructor 557 // isn't completely accurate; we'd prefer to check that the initializer 558 // has no side effects. 559 if (RD->hasUserDeclaredConstructor() || !RD->hasTrivialDestructor()) 560 return false; 561 } 562 } 563 564 // TODO: __attribute__((unused)) templates? 565 } 566 567 return true; 568} 569 570void Sema::DiagnoseUnusedDecl(const NamedDecl *D) { 571 if (!ShouldDiagnoseUnusedDecl(D)) 572 return; 573 574 if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable()) 575 Diag(D->getLocation(), diag::warn_unused_exception_param) 576 << D->getDeclName(); 577 else 578 Diag(D->getLocation(), diag::warn_unused_variable) 579 << D->getDeclName(); 580} 581 582void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 583 if (S->decl_empty()) return; 584 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 585 "Scope shouldn't contain decls!"); 586 587 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 588 I != E; ++I) { 589 Decl *TmpD = (*I).getAs<Decl>(); 590 assert(TmpD && "This decl didn't get pushed??"); 591 592 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 593 NamedDecl *D = cast<NamedDecl>(TmpD); 594 595 if (!D->getDeclName()) continue; 596 597 // Diagnose unused variables in this scope. 598 if (S->getNumErrorsAtStart() == getDiagnostics().getNumErrors()) 599 DiagnoseUnusedDecl(D); 600 601 // Remove this name from our lexical scope. 602 IdResolver.RemoveDecl(D); 603 } 604} 605 606/// \brief Look for an Objective-C class in the translation unit. 607/// 608/// \param Id The name of the Objective-C class we're looking for. If 609/// typo-correction fixes this name, the Id will be updated 610/// to the fixed name. 611/// 612/// \param IdLoc The location of the name in the translation unit. 613/// 614/// \param TypoCorrection If true, this routine will attempt typo correction 615/// if there is no class with the given name. 616/// 617/// \returns The declaration of the named Objective-C class, or NULL if the 618/// class could not be found. 619ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 620 SourceLocation IdLoc, 621 bool TypoCorrection) { 622 // The third "scope" argument is 0 since we aren't enabling lazy built-in 623 // creation from this context. 624 NamedDecl *IDecl = LookupSingleName(TUScope, Id, IdLoc, LookupOrdinaryName); 625 626 if (!IDecl && TypoCorrection) { 627 // Perform typo correction at the given location, but only if we 628 // find an Objective-C class name. 629 LookupResult R(*this, Id, IdLoc, LookupOrdinaryName); 630 if (CorrectTypo(R, TUScope, 0, 0, false, CTC_NoKeywords) && 631 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 632 Diag(IdLoc, diag::err_undef_interface_suggest) 633 << Id << IDecl->getDeclName() 634 << FixItHint::CreateReplacement(IdLoc, IDecl->getNameAsString()); 635 Diag(IDecl->getLocation(), diag::note_previous_decl) 636 << IDecl->getDeclName(); 637 638 Id = IDecl->getIdentifier(); 639 } 640 } 641 642 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 643} 644 645/// getNonFieldDeclScope - Retrieves the innermost scope, starting 646/// from S, where a non-field would be declared. This routine copes 647/// with the difference between C and C++ scoping rules in structs and 648/// unions. For example, the following code is well-formed in C but 649/// ill-formed in C++: 650/// @code 651/// struct S6 { 652/// enum { BAR } e; 653/// }; 654/// 655/// void test_S6() { 656/// struct S6 a; 657/// a.e = BAR; 658/// } 659/// @endcode 660/// For the declaration of BAR, this routine will return a different 661/// scope. The scope S will be the scope of the unnamed enumeration 662/// within S6. In C++, this routine will return the scope associated 663/// with S6, because the enumeration's scope is a transparent 664/// context but structures can contain non-field names. In C, this 665/// routine will return the translation unit scope, since the 666/// enumeration's scope is a transparent context and structures cannot 667/// contain non-field names. 668Scope *Sema::getNonFieldDeclScope(Scope *S) { 669 while (((S->getFlags() & Scope::DeclScope) == 0) || 670 (S->getEntity() && 671 ((DeclContext *)S->getEntity())->isTransparentContext()) || 672 (S->isClassScope() && !getLangOptions().CPlusPlus)) 673 S = S->getParent(); 674 return S; 675} 676 677void Sema::InitBuiltinVaListType() { 678 if (!Context.getBuiltinVaListType().isNull()) 679 return; 680 681 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 682 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, SourceLocation(), 683 LookupOrdinaryName, ForRedeclaration); 684 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 685 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 686} 687 688/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 689/// file scope. lazily create a decl for it. ForRedeclaration is true 690/// if we're creating this built-in in anticipation of redeclaring the 691/// built-in. 692NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 693 Scope *S, bool ForRedeclaration, 694 SourceLocation Loc) { 695 Builtin::ID BID = (Builtin::ID)bid; 696 697 if (Context.BuiltinInfo.hasVAListUse(BID)) 698 InitBuiltinVaListType(); 699 700 ASTContext::GetBuiltinTypeError Error; 701 QualType R = Context.GetBuiltinType(BID, Error); 702 switch (Error) { 703 case ASTContext::GE_None: 704 // Okay 705 break; 706 707 case ASTContext::GE_Missing_stdio: 708 if (ForRedeclaration) 709 Diag(Loc, diag::err_implicit_decl_requires_stdio) 710 << Context.BuiltinInfo.GetName(BID); 711 return 0; 712 713 case ASTContext::GE_Missing_setjmp: 714 if (ForRedeclaration) 715 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 716 << Context.BuiltinInfo.GetName(BID); 717 return 0; 718 } 719 720 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 721 Diag(Loc, diag::ext_implicit_lib_function_decl) 722 << Context.BuiltinInfo.GetName(BID) 723 << R; 724 if (Context.BuiltinInfo.getHeaderName(BID) && 725 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 726 != Diagnostic::Ignored) 727 Diag(Loc, diag::note_please_include_header) 728 << Context.BuiltinInfo.getHeaderName(BID) 729 << Context.BuiltinInfo.GetName(BID); 730 } 731 732 FunctionDecl *New = FunctionDecl::Create(Context, 733 Context.getTranslationUnitDecl(), 734 Loc, II, R, /*TInfo=*/0, 735 FunctionDecl::Extern, 736 FunctionDecl::None, false, 737 /*hasPrototype=*/true); 738 New->setImplicit(); 739 740 // Create Decl objects for each parameter, adding them to the 741 // FunctionDecl. 742 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 743 llvm::SmallVector<ParmVarDecl*, 16> Params; 744 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 745 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 746 FT->getArgType(i), /*TInfo=*/0, 747 VarDecl::None, VarDecl::None, 0)); 748 New->setParams(Params.data(), Params.size()); 749 } 750 751 AddKnownFunctionAttributes(New); 752 753 // TUScope is the translation-unit scope to insert this function into. 754 // FIXME: This is hideous. We need to teach PushOnScopeChains to 755 // relate Scopes to DeclContexts, and probably eliminate CurContext 756 // entirely, but we're not there yet. 757 DeclContext *SavedContext = CurContext; 758 CurContext = Context.getTranslationUnitDecl(); 759 PushOnScopeChains(New, TUScope); 760 CurContext = SavedContext; 761 return New; 762} 763 764/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 765/// same name and scope as a previous declaration 'Old'. Figure out 766/// how to resolve this situation, merging decls or emitting 767/// diagnostics as appropriate. If there was an error, set New to be invalid. 768/// 769void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 770 // If the new decl is known invalid already, don't bother doing any 771 // merging checks. 772 if (New->isInvalidDecl()) return; 773 774 // Allow multiple definitions for ObjC built-in typedefs. 775 // FIXME: Verify the underlying types are equivalent! 776 if (getLangOptions().ObjC1) { 777 const IdentifierInfo *TypeID = New->getIdentifier(); 778 switch (TypeID->getLength()) { 779 default: break; 780 case 2: 781 if (!TypeID->isStr("id")) 782 break; 783 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 784 // Install the built-in type for 'id', ignoring the current definition. 785 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 786 return; 787 case 5: 788 if (!TypeID->isStr("Class")) 789 break; 790 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 791 // Install the built-in type for 'Class', ignoring the current definition. 792 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 793 return; 794 case 3: 795 if (!TypeID->isStr("SEL")) 796 break; 797 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 798 // Install the built-in type for 'SEL', ignoring the current definition. 799 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 800 return; 801 case 8: 802 if (!TypeID->isStr("Protocol")) 803 break; 804 Context.setObjCProtoType(New->getUnderlyingType()); 805 return; 806 } 807 // Fall through - the typedef name was not a builtin type. 808 } 809 810 // Verify the old decl was also a type. 811 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 812 if (!Old) { 813 Diag(New->getLocation(), diag::err_redefinition_different_kind) 814 << New->getDeclName(); 815 816 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 817 if (OldD->getLocation().isValid()) 818 Diag(OldD->getLocation(), diag::note_previous_definition); 819 820 return New->setInvalidDecl(); 821 } 822 823 // If the old declaration is invalid, just give up here. 824 if (Old->isInvalidDecl()) 825 return New->setInvalidDecl(); 826 827 // Determine the "old" type we'll use for checking and diagnostics. 828 QualType OldType; 829 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 830 OldType = OldTypedef->getUnderlyingType(); 831 else 832 OldType = Context.getTypeDeclType(Old); 833 834 // If the typedef types are not identical, reject them in all languages and 835 // with any extensions enabled. 836 837 if (OldType != New->getUnderlyingType() && 838 Context.getCanonicalType(OldType) != 839 Context.getCanonicalType(New->getUnderlyingType())) { 840 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 841 << New->getUnderlyingType() << OldType; 842 if (Old->getLocation().isValid()) 843 Diag(Old->getLocation(), diag::note_previous_definition); 844 return New->setInvalidDecl(); 845 } 846 847 // The types match. Link up the redeclaration chain if the old 848 // declaration was a typedef. 849 // FIXME: this is a potential source of wierdness if the type 850 // spellings don't match exactly. 851 if (isa<TypedefDecl>(Old)) 852 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 853 854 if (getLangOptions().Microsoft) 855 return; 856 857 if (getLangOptions().CPlusPlus) { 858 // C++ [dcl.typedef]p2: 859 // In a given non-class scope, a typedef specifier can be used to 860 // redefine the name of any type declared in that scope to refer 861 // to the type to which it already refers. 862 if (!isa<CXXRecordDecl>(CurContext)) 863 return; 864 865 // C++0x [dcl.typedef]p4: 866 // In a given class scope, a typedef specifier can be used to redefine 867 // any class-name declared in that scope that is not also a typedef-name 868 // to refer to the type to which it already refers. 869 // 870 // This wording came in via DR424, which was a correction to the 871 // wording in DR56, which accidentally banned code like: 872 // 873 // struct S { 874 // typedef struct A { } A; 875 // }; 876 // 877 // in the C++03 standard. We implement the C++0x semantics, which 878 // allow the above but disallow 879 // 880 // struct S { 881 // typedef int I; 882 // typedef int I; 883 // }; 884 // 885 // since that was the intent of DR56. 886 if (!isa<TypedefDecl >(Old)) 887 return; 888 889 Diag(New->getLocation(), diag::err_redefinition) 890 << New->getDeclName(); 891 Diag(Old->getLocation(), diag::note_previous_definition); 892 return New->setInvalidDecl(); 893 } 894 895 // If we have a redefinition of a typedef in C, emit a warning. This warning 896 // is normally mapped to an error, but can be controlled with 897 // -Wtypedef-redefinition. If either the original or the redefinition is 898 // in a system header, don't emit this for compatibility with GCC. 899 if (getDiagnostics().getSuppressSystemWarnings() && 900 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 901 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 902 return; 903 904 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 905 << New->getDeclName(); 906 Diag(Old->getLocation(), diag::note_previous_definition); 907 return; 908} 909 910/// DeclhasAttr - returns true if decl Declaration already has the target 911/// attribute. 912static bool 913DeclHasAttr(const Decl *decl, const Attr *target) { 914 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 915 if (attr->getKind() == target->getKind()) 916 return true; 917 918 return false; 919} 920 921/// MergeAttributes - append attributes from the Old decl to the New one. 922static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 923 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 924 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 925 Attr *NewAttr = attr->clone(C); 926 NewAttr->setInherited(true); 927 New->addAttr(NewAttr); 928 } 929 } 930} 931 932namespace { 933 934/// Used in MergeFunctionDecl to keep track of function parameters in 935/// C. 936struct GNUCompatibleParamWarning { 937 ParmVarDecl *OldParm; 938 ParmVarDecl *NewParm; 939 QualType PromotedType; 940}; 941 942} 943 944/// getSpecialMember - get the special member enum for a method. 945Sema::CXXSpecialMember Sema::getSpecialMember(const CXXMethodDecl *MD) { 946 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 947 if (Ctor->isCopyConstructor()) 948 return Sema::CXXCopyConstructor; 949 950 return Sema::CXXConstructor; 951 } 952 953 if (isa<CXXDestructorDecl>(MD)) 954 return Sema::CXXDestructor; 955 956 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 957 return Sema::CXXCopyAssignment; 958} 959 960/// canRedefineFunction - checks if a function can be redefined. Currently, 961/// only extern inline functions can be redefined, and even then only in 962/// GNU89 mode. 963static bool canRedefineFunction(const FunctionDecl *FD, 964 const LangOptions& LangOpts) { 965 return (LangOpts.GNUMode && !LangOpts.C99 && !LangOpts.CPlusPlus && 966 FD->isInlineSpecified() && 967 FD->getStorageClass() == FunctionDecl::Extern); 968} 969 970/// MergeFunctionDecl - We just parsed a function 'New' from 971/// declarator D which has the same name and scope as a previous 972/// declaration 'Old'. Figure out how to resolve this situation, 973/// merging decls or emitting diagnostics as appropriate. 974/// 975/// In C++, New and Old must be declarations that are not 976/// overloaded. Use IsOverload to determine whether New and Old are 977/// overloaded, and to select the Old declaration that New should be 978/// merged with. 979/// 980/// Returns true if there was an error, false otherwise. 981bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 982 // Verify the old decl was also a function. 983 FunctionDecl *Old = 0; 984 if (FunctionTemplateDecl *OldFunctionTemplate 985 = dyn_cast<FunctionTemplateDecl>(OldD)) 986 Old = OldFunctionTemplate->getTemplatedDecl(); 987 else 988 Old = dyn_cast<FunctionDecl>(OldD); 989 if (!Old) { 990 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 991 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 992 Diag(Shadow->getTargetDecl()->getLocation(), 993 diag::note_using_decl_target); 994 Diag(Shadow->getUsingDecl()->getLocation(), 995 diag::note_using_decl) << 0; 996 return true; 997 } 998 999 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1000 << New->getDeclName(); 1001 Diag(OldD->getLocation(), diag::note_previous_definition); 1002 return true; 1003 } 1004 1005 // Determine whether the previous declaration was a definition, 1006 // implicit declaration, or a declaration. 1007 diag::kind PrevDiag; 1008 if (Old->isThisDeclarationADefinition()) 1009 PrevDiag = diag::note_previous_definition; 1010 else if (Old->isImplicit()) 1011 PrevDiag = diag::note_previous_implicit_declaration; 1012 else 1013 PrevDiag = diag::note_previous_declaration; 1014 1015 QualType OldQType = Context.getCanonicalType(Old->getType()); 1016 QualType NewQType = Context.getCanonicalType(New->getType()); 1017 1018 // Don't complain about this if we're in GNU89 mode and the old function 1019 // is an extern inline function. 1020 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 1021 New->getStorageClass() == FunctionDecl::Static && 1022 Old->getStorageClass() != FunctionDecl::Static && 1023 !canRedefineFunction(Old, getLangOptions())) { 1024 Diag(New->getLocation(), diag::err_static_non_static) 1025 << New; 1026 Diag(Old->getLocation(), PrevDiag); 1027 return true; 1028 } 1029 1030 // If a function is first declared with a calling convention, but is 1031 // later declared or defined without one, the second decl assumes the 1032 // calling convention of the first. 1033 // 1034 // For the new decl, we have to look at the NON-canonical type to tell the 1035 // difference between a function that really doesn't have a calling 1036 // convention and one that is declared cdecl. That's because in 1037 // canonicalization (see ASTContext.cpp), cdecl is canonicalized away 1038 // because it is the default calling convention. 1039 // 1040 // Note also that we DO NOT return at this point, because we still have 1041 // other tests to run. 1042 const FunctionType *OldType = OldQType->getAs<FunctionType>(); 1043 const FunctionType *NewType = New->getType()->getAs<FunctionType>(); 1044 const FunctionType::ExtInfo OldTypeInfo = OldType->getExtInfo(); 1045 const FunctionType::ExtInfo NewTypeInfo = NewType->getExtInfo(); 1046 if (OldTypeInfo.getCC() != CC_Default && 1047 NewTypeInfo.getCC() == CC_Default) { 1048 NewQType = Context.getCallConvType(NewQType, OldTypeInfo.getCC()); 1049 New->setType(NewQType); 1050 NewQType = Context.getCanonicalType(NewQType); 1051 } else if (!Context.isSameCallConv(OldTypeInfo.getCC(), 1052 NewTypeInfo.getCC())) { 1053 // Calling conventions really aren't compatible, so complain. 1054 Diag(New->getLocation(), diag::err_cconv_change) 1055 << FunctionType::getNameForCallConv(NewTypeInfo.getCC()) 1056 << (OldTypeInfo.getCC() == CC_Default) 1057 << (OldTypeInfo.getCC() == CC_Default ? "" : 1058 FunctionType::getNameForCallConv(OldTypeInfo.getCC())); 1059 Diag(Old->getLocation(), diag::note_previous_declaration); 1060 return true; 1061 } 1062 1063 // FIXME: diagnose the other way around? 1064 if (OldType->getNoReturnAttr() && !NewType->getNoReturnAttr()) { 1065 NewQType = Context.getNoReturnType(NewQType); 1066 New->setType(NewQType); 1067 assert(NewQType.isCanonical()); 1068 } 1069 1070 // Merge regparm attribute. 1071 if (OldType->getRegParmType() != NewType->getRegParmType()) { 1072 if (NewType->getRegParmType()) { 1073 Diag(New->getLocation(), diag::err_regparm_mismatch) 1074 << NewType->getRegParmType() 1075 << OldType->getRegParmType(); 1076 Diag(Old->getLocation(), diag::note_previous_declaration); 1077 return true; 1078 } 1079 1080 NewQType = Context.getRegParmType(NewQType, OldType->getRegParmType()); 1081 New->setType(NewQType); 1082 assert(NewQType.isCanonical()); 1083 } 1084 1085 if (getLangOptions().CPlusPlus) { 1086 // (C++98 13.1p2): 1087 // Certain function declarations cannot be overloaded: 1088 // -- Function declarations that differ only in the return type 1089 // cannot be overloaded. 1090 QualType OldReturnType 1091 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 1092 QualType NewReturnType 1093 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 1094 QualType ResQT; 1095 if (OldReturnType != NewReturnType) { 1096 if (NewReturnType->isObjCObjectPointerType() 1097 && OldReturnType->isObjCObjectPointerType()) 1098 ResQT = Context.mergeObjCGCQualifiers(NewQType, OldQType); 1099 if (ResQT.isNull()) { 1100 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 1101 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1102 return true; 1103 } 1104 else 1105 NewQType = ResQT; 1106 } 1107 1108 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 1109 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 1110 if (OldMethod && NewMethod) { 1111 // Preserve triviality. 1112 NewMethod->setTrivial(OldMethod->isTrivial()); 1113 1114 bool isFriend = NewMethod->getFriendObjectKind(); 1115 1116 if (!isFriend && NewMethod->getLexicalDeclContext()->isRecord()) { 1117 // -- Member function declarations with the same name and the 1118 // same parameter types cannot be overloaded if any of them 1119 // is a static member function declaration. 1120 if (OldMethod->isStatic() || NewMethod->isStatic()) { 1121 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 1122 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1123 return true; 1124 } 1125 1126 // C++ [class.mem]p1: 1127 // [...] A member shall not be declared twice in the 1128 // member-specification, except that a nested class or member 1129 // class template can be declared and then later defined. 1130 unsigned NewDiag; 1131 if (isa<CXXConstructorDecl>(OldMethod)) 1132 NewDiag = diag::err_constructor_redeclared; 1133 else if (isa<CXXDestructorDecl>(NewMethod)) 1134 NewDiag = diag::err_destructor_redeclared; 1135 else if (isa<CXXConversionDecl>(NewMethod)) 1136 NewDiag = diag::err_conv_function_redeclared; 1137 else 1138 NewDiag = diag::err_member_redeclared; 1139 1140 Diag(New->getLocation(), NewDiag); 1141 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1142 1143 // Complain if this is an explicit declaration of a special 1144 // member that was initially declared implicitly. 1145 // 1146 // As an exception, it's okay to befriend such methods in order 1147 // to permit the implicit constructor/destructor/operator calls. 1148 } else if (OldMethod->isImplicit()) { 1149 if (isFriend) { 1150 NewMethod->setImplicit(); 1151 } else { 1152 Diag(NewMethod->getLocation(), 1153 diag::err_definition_of_implicitly_declared_member) 1154 << New << getSpecialMember(OldMethod); 1155 return true; 1156 } 1157 } 1158 } 1159 1160 // (C++98 8.3.5p3): 1161 // All declarations for a function shall agree exactly in both the 1162 // return type and the parameter-type-list. 1163 // attributes should be ignored when comparing. 1164 if (Context.getNoReturnType(OldQType, false) == 1165 Context.getNoReturnType(NewQType, false)) 1166 return MergeCompatibleFunctionDecls(New, Old); 1167 1168 // Fall through for conflicting redeclarations and redefinitions. 1169 } 1170 1171 // C: Function types need to be compatible, not identical. This handles 1172 // duplicate function decls like "void f(int); void f(enum X);" properly. 1173 if (!getLangOptions().CPlusPlus && 1174 Context.typesAreCompatible(OldQType, NewQType)) { 1175 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1176 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1177 const FunctionProtoType *OldProto = 0; 1178 if (isa<FunctionNoProtoType>(NewFuncType) && 1179 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1180 // The old declaration provided a function prototype, but the 1181 // new declaration does not. Merge in the prototype. 1182 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1183 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1184 OldProto->arg_type_end()); 1185 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1186 ParamTypes.data(), ParamTypes.size(), 1187 OldProto->isVariadic(), 1188 OldProto->getTypeQuals(), 1189 false, false, 0, 0, 1190 OldProto->getExtInfo()); 1191 New->setType(NewQType); 1192 New->setHasInheritedPrototype(); 1193 1194 // Synthesize a parameter for each argument type. 1195 llvm::SmallVector<ParmVarDecl*, 16> Params; 1196 for (FunctionProtoType::arg_type_iterator 1197 ParamType = OldProto->arg_type_begin(), 1198 ParamEnd = OldProto->arg_type_end(); 1199 ParamType != ParamEnd; ++ParamType) { 1200 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1201 SourceLocation(), 0, 1202 *ParamType, /*TInfo=*/0, 1203 VarDecl::None, VarDecl::None, 1204 0); 1205 Param->setImplicit(); 1206 Params.push_back(Param); 1207 } 1208 1209 New->setParams(Params.data(), Params.size()); 1210 } 1211 1212 return MergeCompatibleFunctionDecls(New, Old); 1213 } 1214 1215 // GNU C permits a K&R definition to follow a prototype declaration 1216 // if the declared types of the parameters in the K&R definition 1217 // match the types in the prototype declaration, even when the 1218 // promoted types of the parameters from the K&R definition differ 1219 // from the types in the prototype. GCC then keeps the types from 1220 // the prototype. 1221 // 1222 // If a variadic prototype is followed by a non-variadic K&R definition, 1223 // the K&R definition becomes variadic. This is sort of an edge case, but 1224 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1225 // C99 6.9.1p8. 1226 if (!getLangOptions().CPlusPlus && 1227 Old->hasPrototype() && !New->hasPrototype() && 1228 New->getType()->getAs<FunctionProtoType>() && 1229 Old->getNumParams() == New->getNumParams()) { 1230 llvm::SmallVector<QualType, 16> ArgTypes; 1231 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1232 const FunctionProtoType *OldProto 1233 = Old->getType()->getAs<FunctionProtoType>(); 1234 const FunctionProtoType *NewProto 1235 = New->getType()->getAs<FunctionProtoType>(); 1236 1237 // Determine whether this is the GNU C extension. 1238 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1239 NewProto->getResultType()); 1240 bool LooseCompatible = !MergedReturn.isNull(); 1241 for (unsigned Idx = 0, End = Old->getNumParams(); 1242 LooseCompatible && Idx != End; ++Idx) { 1243 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1244 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1245 if (Context.typesAreCompatible(OldParm->getType(), 1246 NewProto->getArgType(Idx))) { 1247 ArgTypes.push_back(NewParm->getType()); 1248 } else if (Context.typesAreCompatible(OldParm->getType(), 1249 NewParm->getType(), 1250 /*CompareUnqualified=*/true)) { 1251 GNUCompatibleParamWarning Warn 1252 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1253 Warnings.push_back(Warn); 1254 ArgTypes.push_back(NewParm->getType()); 1255 } else 1256 LooseCompatible = false; 1257 } 1258 1259 if (LooseCompatible) { 1260 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1261 Diag(Warnings[Warn].NewParm->getLocation(), 1262 diag::ext_param_promoted_not_compatible_with_prototype) 1263 << Warnings[Warn].PromotedType 1264 << Warnings[Warn].OldParm->getType(); 1265 if (Warnings[Warn].OldParm->getLocation().isValid()) 1266 Diag(Warnings[Warn].OldParm->getLocation(), 1267 diag::note_previous_declaration); 1268 } 1269 1270 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1271 ArgTypes.size(), 1272 OldProto->isVariadic(), 0, 1273 false, false, 0, 0, 1274 OldProto->getExtInfo())); 1275 return MergeCompatibleFunctionDecls(New, Old); 1276 } 1277 1278 // Fall through to diagnose conflicting types. 1279 } 1280 1281 // A function that has already been declared has been redeclared or defined 1282 // with a different type- show appropriate diagnostic 1283 if (unsigned BuiltinID = Old->getBuiltinID()) { 1284 // The user has declared a builtin function with an incompatible 1285 // signature. 1286 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1287 // The function the user is redeclaring is a library-defined 1288 // function like 'malloc' or 'printf'. Warn about the 1289 // redeclaration, then pretend that we don't know about this 1290 // library built-in. 1291 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1292 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1293 << Old << Old->getType(); 1294 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1295 Old->setInvalidDecl(); 1296 return false; 1297 } 1298 1299 PrevDiag = diag::note_previous_builtin_declaration; 1300 } 1301 1302 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1303 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1304 return true; 1305} 1306 1307/// \brief Completes the merge of two function declarations that are 1308/// known to be compatible. 1309/// 1310/// This routine handles the merging of attributes and other 1311/// properties of function declarations form the old declaration to 1312/// the new declaration, once we know that New is in fact a 1313/// redeclaration of Old. 1314/// 1315/// \returns false 1316bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1317 // Merge the attributes 1318 MergeAttributes(New, Old, Context); 1319 1320 // Merge the storage class. 1321 if (Old->getStorageClass() != FunctionDecl::Extern && 1322 Old->getStorageClass() != FunctionDecl::None) 1323 New->setStorageClass(Old->getStorageClass()); 1324 1325 // Merge "pure" flag. 1326 if (Old->isPure()) 1327 New->setPure(); 1328 1329 // Merge the "deleted" flag. 1330 if (Old->isDeleted()) 1331 New->setDeleted(); 1332 1333 if (getLangOptions().CPlusPlus) 1334 return MergeCXXFunctionDecl(New, Old); 1335 1336 return false; 1337} 1338 1339/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1340/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1341/// situation, merging decls or emitting diagnostics as appropriate. 1342/// 1343/// Tentative definition rules (C99 6.9.2p2) are checked by 1344/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1345/// definitions here, since the initializer hasn't been attached. 1346/// 1347void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1348 // If the new decl is already invalid, don't do any other checking. 1349 if (New->isInvalidDecl()) 1350 return; 1351 1352 // Verify the old decl was also a variable. 1353 VarDecl *Old = 0; 1354 if (!Previous.isSingleResult() || 1355 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1356 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1357 << New->getDeclName(); 1358 Diag(Previous.getRepresentativeDecl()->getLocation(), 1359 diag::note_previous_definition); 1360 return New->setInvalidDecl(); 1361 } 1362 1363 MergeAttributes(New, Old, Context); 1364 1365 // Merge the types 1366 QualType MergedT; 1367 if (getLangOptions().CPlusPlus) { 1368 if (Context.hasSameType(New->getType(), Old->getType())) 1369 MergedT = New->getType(); 1370 // C++ [basic.link]p10: 1371 // [...] the types specified by all declarations referring to a given 1372 // object or function shall be identical, except that declarations for an 1373 // array object can specify array types that differ by the presence or 1374 // absence of a major array bound (8.3.4). 1375 else if (Old->getType()->isIncompleteArrayType() && 1376 New->getType()->isArrayType()) { 1377 CanQual<ArrayType> OldArray 1378 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1379 CanQual<ArrayType> NewArray 1380 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1381 if (OldArray->getElementType() == NewArray->getElementType()) 1382 MergedT = New->getType(); 1383 } else if (Old->getType()->isArrayType() && 1384 New->getType()->isIncompleteArrayType()) { 1385 CanQual<ArrayType> OldArray 1386 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1387 CanQual<ArrayType> NewArray 1388 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1389 if (OldArray->getElementType() == NewArray->getElementType()) 1390 MergedT = Old->getType(); 1391 } else if (New->getType()->isObjCObjectPointerType() 1392 && Old->getType()->isObjCObjectPointerType()) { 1393 MergedT = Context.mergeObjCGCQualifiers(New->getType(), Old->getType()); 1394 } 1395 } else { 1396 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1397 } 1398 if (MergedT.isNull()) { 1399 Diag(New->getLocation(), diag::err_redefinition_different_type) 1400 << New->getDeclName(); 1401 Diag(Old->getLocation(), diag::note_previous_definition); 1402 return New->setInvalidDecl(); 1403 } 1404 New->setType(MergedT); 1405 1406 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1407 if (New->getStorageClass() == VarDecl::Static && 1408 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1409 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1410 Diag(Old->getLocation(), diag::note_previous_definition); 1411 return New->setInvalidDecl(); 1412 } 1413 // C99 6.2.2p4: 1414 // For an identifier declared with the storage-class specifier 1415 // extern in a scope in which a prior declaration of that 1416 // identifier is visible,23) if the prior declaration specifies 1417 // internal or external linkage, the linkage of the identifier at 1418 // the later declaration is the same as the linkage specified at 1419 // the prior declaration. If no prior declaration is visible, or 1420 // if the prior declaration specifies no linkage, then the 1421 // identifier has external linkage. 1422 if (New->hasExternalStorage() && Old->hasLinkage()) 1423 /* Okay */; 1424 else if (New->getStorageClass() != VarDecl::Static && 1425 Old->getStorageClass() == VarDecl::Static) { 1426 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1427 Diag(Old->getLocation(), diag::note_previous_definition); 1428 return New->setInvalidDecl(); 1429 } 1430 1431 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1432 1433 // FIXME: The test for external storage here seems wrong? We still 1434 // need to check for mismatches. 1435 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1436 // Don't complain about out-of-line definitions of static members. 1437 !(Old->getLexicalDeclContext()->isRecord() && 1438 !New->getLexicalDeclContext()->isRecord())) { 1439 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1440 Diag(Old->getLocation(), diag::note_previous_definition); 1441 return New->setInvalidDecl(); 1442 } 1443 1444 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1445 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1446 Diag(Old->getLocation(), diag::note_previous_definition); 1447 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1448 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1449 Diag(Old->getLocation(), diag::note_previous_definition); 1450 } 1451 1452 // C++ doesn't have tentative definitions, so go right ahead and check here. 1453 const VarDecl *Def; 1454 if (getLangOptions().CPlusPlus && 1455 New->isThisDeclarationADefinition() == VarDecl::Definition && 1456 (Def = Old->getDefinition())) { 1457 Diag(New->getLocation(), diag::err_redefinition) 1458 << New->getDeclName(); 1459 Diag(Def->getLocation(), diag::note_previous_definition); 1460 New->setInvalidDecl(); 1461 return; 1462 } 1463 // c99 6.2.2 P4. 1464 // For an identifier declared with the storage-class specifier extern in a 1465 // scope in which a prior declaration of that identifier is visible, if 1466 // the prior declaration specifies internal or external linkage, the linkage 1467 // of the identifier at the later declaration is the same as the linkage 1468 // specified at the prior declaration. 1469 // FIXME. revisit this code. 1470 if (New->hasExternalStorage() && 1471 Old->getLinkage() == InternalLinkage && 1472 New->getDeclContext() == Old->getDeclContext()) 1473 New->setStorageClass(Old->getStorageClass()); 1474 1475 // Keep a chain of previous declarations. 1476 New->setPreviousDeclaration(Old); 1477 1478 // Inherit access appropriately. 1479 New->setAccess(Old->getAccess()); 1480} 1481 1482/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1483/// no declarator (e.g. "struct foo;") is parsed. 1484Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, 1485 DeclSpec &DS) { 1486 // FIXME: Error on auto/register at file scope 1487 // FIXME: Error on inline/virtual/explicit 1488 // FIXME: Warn on useless __thread 1489 // FIXME: Warn on useless const/volatile 1490 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1491 // FIXME: Warn on useless attributes 1492 Decl *TagD = 0; 1493 TagDecl *Tag = 0; 1494 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1495 DS.getTypeSpecType() == DeclSpec::TST_struct || 1496 DS.getTypeSpecType() == DeclSpec::TST_union || 1497 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1498 TagD = static_cast<Decl *>(DS.getTypeRep()); 1499 1500 if (!TagD) // We probably had an error 1501 return DeclPtrTy(); 1502 1503 // Note that the above type specs guarantee that the 1504 // type rep is a Decl, whereas in many of the others 1505 // it's a Type. 1506 Tag = dyn_cast<TagDecl>(TagD); 1507 } 1508 1509 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1510 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1511 // or incomplete types shall not be restrict-qualified." 1512 if (TypeQuals & DeclSpec::TQ_restrict) 1513 Diag(DS.getRestrictSpecLoc(), 1514 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1515 << DS.getSourceRange(); 1516 } 1517 1518 if (DS.isFriendSpecified()) { 1519 // If we're dealing with a class template decl, assume that the 1520 // template routines are handling it. 1521 if (TagD && isa<ClassTemplateDecl>(TagD)) 1522 return DeclPtrTy(); 1523 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1524 } 1525 1526 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1527 // If there are attributes in the DeclSpec, apply them to the record. 1528 if (const AttributeList *AL = DS.getAttributes()) 1529 ProcessDeclAttributeList(S, Record, AL); 1530 1531 if (!Record->getDeclName() && Record->isDefinition() && 1532 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1533 if (getLangOptions().CPlusPlus || 1534 Record->getDeclContext()->isRecord()) 1535 return BuildAnonymousStructOrUnion(S, DS, AS, Record); 1536 1537 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1538 << DS.getSourceRange(); 1539 } 1540 1541 // Microsoft allows unnamed struct/union fields. Don't complain 1542 // about them. 1543 // FIXME: Should we support Microsoft's extensions in this area? 1544 if (Record->getDeclName() && getLangOptions().Microsoft) 1545 return DeclPtrTy::make(Tag); 1546 } 1547 1548 if (getLangOptions().CPlusPlus && 1549 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 1550 if (EnumDecl *Enum = dyn_cast_or_null<EnumDecl>(Tag)) 1551 if (Enum->enumerator_begin() == Enum->enumerator_end() && 1552 !Enum->getIdentifier() && !Enum->isInvalidDecl()) 1553 Diag(Enum->getLocation(), diag::ext_no_declarators) 1554 << DS.getSourceRange(); 1555 1556 if (!DS.isMissingDeclaratorOk() && 1557 DS.getTypeSpecType() != DeclSpec::TST_error) { 1558 // Warn about typedefs of enums without names, since this is an 1559 // extension in both Microsoft and GNU. 1560 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1561 Tag && isa<EnumDecl>(Tag)) { 1562 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1563 << DS.getSourceRange(); 1564 return DeclPtrTy::make(Tag); 1565 } 1566 1567 Diag(DS.getSourceRange().getBegin(), diag::ext_no_declarators) 1568 << DS.getSourceRange(); 1569 } 1570 1571 return DeclPtrTy::make(TagD); 1572} 1573 1574/// We are trying to inject an anonymous member into the given scope; 1575/// check if there's an existing declaration that can't be overloaded. 1576/// 1577/// \return true if this is a forbidden redeclaration 1578static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1579 Scope *S, 1580 DeclContext *Owner, 1581 DeclarationName Name, 1582 SourceLocation NameLoc, 1583 unsigned diagnostic) { 1584 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1585 Sema::ForRedeclaration); 1586 if (!SemaRef.LookupName(R, S)) return false; 1587 1588 if (R.getAsSingle<TagDecl>()) 1589 return false; 1590 1591 // Pick a representative declaration. 1592 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1593 if (PrevDecl && Owner->isRecord()) { 1594 RecordDecl *Record = cast<RecordDecl>(Owner); 1595 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1596 return false; 1597 } 1598 1599 SemaRef.Diag(NameLoc, diagnostic) << Name; 1600 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1601 1602 return true; 1603} 1604 1605/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1606/// anonymous struct or union AnonRecord into the owning context Owner 1607/// and scope S. This routine will be invoked just after we realize 1608/// that an unnamed union or struct is actually an anonymous union or 1609/// struct, e.g., 1610/// 1611/// @code 1612/// union { 1613/// int i; 1614/// float f; 1615/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1616/// // f into the surrounding scope.x 1617/// @endcode 1618/// 1619/// This routine is recursive, injecting the names of nested anonymous 1620/// structs/unions into the owning context and scope as well. 1621static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S, 1622 DeclContext *Owner, 1623 RecordDecl *AnonRecord, 1624 AccessSpecifier AS) { 1625 unsigned diagKind 1626 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1627 : diag::err_anonymous_struct_member_redecl; 1628 1629 bool Invalid = false; 1630 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1631 FEnd = AnonRecord->field_end(); 1632 F != FEnd; ++F) { 1633 if ((*F)->getDeclName()) { 1634 if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, (*F)->getDeclName(), 1635 (*F)->getLocation(), diagKind)) { 1636 // C++ [class.union]p2: 1637 // The names of the members of an anonymous union shall be 1638 // distinct from the names of any other entity in the 1639 // scope in which the anonymous union is declared. 1640 Invalid = true; 1641 } else { 1642 // C++ [class.union]p2: 1643 // For the purpose of name lookup, after the anonymous union 1644 // definition, the members of the anonymous union are 1645 // considered to have been defined in the scope in which the 1646 // anonymous union is declared. 1647 Owner->makeDeclVisibleInContext(*F); 1648 S->AddDecl(Sema::DeclPtrTy::make(*F)); 1649 SemaRef.IdResolver.AddDecl(*F); 1650 1651 // That includes picking up the appropriate access specifier. 1652 if (AS != AS_none) (*F)->setAccess(AS); 1653 } 1654 } else if (const RecordType *InnerRecordType 1655 = (*F)->getType()->getAs<RecordType>()) { 1656 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1657 if (InnerRecord->isAnonymousStructOrUnion()) 1658 Invalid = Invalid || 1659 InjectAnonymousStructOrUnionMembers(SemaRef, S, Owner, 1660 InnerRecord, AS); 1661 } 1662 } 1663 1664 return Invalid; 1665} 1666 1667/// StorageClassSpecToVarDeclStorageClass - Maps a DeclSpec::SCS to 1668/// a VarDecl::StorageClass. Any error reporting is up to the caller: 1669/// illegal input values are mapped to VarDecl::None. 1670/// If the input declaration context is a linkage specification 1671/// with no braces, then Extern is mapped to None. 1672static VarDecl::StorageClass 1673StorageClassSpecToVarDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1674 DeclContext *DC) { 1675 switch (StorageClassSpec) { 1676 case DeclSpec::SCS_unspecified: return VarDecl::None; 1677 case DeclSpec::SCS_extern: 1678 // If the current context is a C++ linkage specification 1679 // having no braces, then the keyword "extern" is properly part 1680 // of the linkage specification itself, rather than being 1681 // the written storage class specifier. 1682 return (DC && isa<LinkageSpecDecl>(DC) && 1683 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1684 ? VarDecl::None : VarDecl::Extern; 1685 case DeclSpec::SCS_static: return VarDecl::Static; 1686 case DeclSpec::SCS_auto: return VarDecl::Auto; 1687 case DeclSpec::SCS_register: return VarDecl::Register; 1688 case DeclSpec::SCS_private_extern: return VarDecl::PrivateExtern; 1689 // Illegal SCSs map to None: error reporting is up to the caller. 1690 case DeclSpec::SCS_mutable: // Fall through. 1691 case DeclSpec::SCS_typedef: return VarDecl::None; 1692 } 1693 llvm_unreachable("unknown storage class specifier"); 1694} 1695 1696/// StorageClassSpecToFunctionDeclStorageClass - Maps a DeclSpec::SCS to 1697/// a FunctionDecl::StorageClass. Any error reporting is up to the caller: 1698/// illegal input values are mapped to FunctionDecl::None. 1699/// If the input declaration context is a linkage specification 1700/// with no braces, then Extern is mapped to None. 1701static FunctionDecl::StorageClass 1702StorageClassSpecToFunctionDeclStorageClass(DeclSpec::SCS StorageClassSpec, 1703 DeclContext *DC) { 1704 switch (StorageClassSpec) { 1705 case DeclSpec::SCS_unspecified: return FunctionDecl::None; 1706 case DeclSpec::SCS_extern: 1707 // If the current context is a C++ linkage specification 1708 // having no braces, then the keyword "extern" is properly part 1709 // of the linkage specification itself, rather than being 1710 // the written storage class specifier. 1711 return (DC && isa<LinkageSpecDecl>(DC) && 1712 !cast<LinkageSpecDecl>(DC)->hasBraces()) 1713 ? FunctionDecl::None : FunctionDecl::Extern; 1714 case DeclSpec::SCS_static: return FunctionDecl::Static; 1715 case DeclSpec::SCS_private_extern: return FunctionDecl::PrivateExtern; 1716 // Illegal SCSs map to None: error reporting is up to the caller. 1717 case DeclSpec::SCS_auto: // Fall through. 1718 case DeclSpec::SCS_mutable: // Fall through. 1719 case DeclSpec::SCS_register: // Fall through. 1720 case DeclSpec::SCS_typedef: return FunctionDecl::None; 1721 } 1722 llvm_unreachable("unknown storage class specifier"); 1723} 1724 1725/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1726/// anonymous structure or union. Anonymous unions are a C++ feature 1727/// (C++ [class.union]) and a GNU C extension; anonymous structures 1728/// are a GNU C and GNU C++ extension. 1729Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1730 AccessSpecifier AS, 1731 RecordDecl *Record) { 1732 DeclContext *Owner = Record->getDeclContext(); 1733 1734 // Diagnose whether this anonymous struct/union is an extension. 1735 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1736 Diag(Record->getLocation(), diag::ext_anonymous_union); 1737 else if (!Record->isUnion()) 1738 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1739 1740 // C and C++ require different kinds of checks for anonymous 1741 // structs/unions. 1742 bool Invalid = false; 1743 if (getLangOptions().CPlusPlus) { 1744 const char* PrevSpec = 0; 1745 unsigned DiagID; 1746 // C++ [class.union]p3: 1747 // Anonymous unions declared in a named namespace or in the 1748 // global namespace shall be declared static. 1749 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1750 (isa<TranslationUnitDecl>(Owner) || 1751 (isa<NamespaceDecl>(Owner) && 1752 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1753 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1754 Invalid = true; 1755 1756 // Recover by adding 'static'. 1757 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1758 PrevSpec, DiagID); 1759 } 1760 // C++ [class.union]p3: 1761 // A storage class is not allowed in a declaration of an 1762 // anonymous union in a class scope. 1763 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1764 isa<RecordDecl>(Owner)) { 1765 Diag(DS.getStorageClassSpecLoc(), 1766 diag::err_anonymous_union_with_storage_spec); 1767 Invalid = true; 1768 1769 // Recover by removing the storage specifier. 1770 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1771 PrevSpec, DiagID); 1772 } 1773 1774 // C++ [class.union]p2: 1775 // The member-specification of an anonymous union shall only 1776 // define non-static data members. [Note: nested types and 1777 // functions cannot be declared within an anonymous union. ] 1778 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1779 MemEnd = Record->decls_end(); 1780 Mem != MemEnd; ++Mem) { 1781 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1782 // C++ [class.union]p3: 1783 // An anonymous union shall not have private or protected 1784 // members (clause 11). 1785 assert(FD->getAccess() != AS_none); 1786 if (FD->getAccess() != AS_public) { 1787 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1788 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1789 Invalid = true; 1790 } 1791 } else if ((*Mem)->isImplicit()) { 1792 // Any implicit members are fine. 1793 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1794 // This is a type that showed up in an 1795 // elaborated-type-specifier inside the anonymous struct or 1796 // union, but which actually declares a type outside of the 1797 // anonymous struct or union. It's okay. 1798 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1799 if (!MemRecord->isAnonymousStructOrUnion() && 1800 MemRecord->getDeclName()) { 1801 // This is a nested type declaration. 1802 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1803 << (int)Record->isUnion(); 1804 Invalid = true; 1805 } 1806 } else if (isa<AccessSpecDecl>(*Mem)) { 1807 // Any access specifier is fine. 1808 } else { 1809 // We have something that isn't a non-static data 1810 // member. Complain about it. 1811 unsigned DK = diag::err_anonymous_record_bad_member; 1812 if (isa<TypeDecl>(*Mem)) 1813 DK = diag::err_anonymous_record_with_type; 1814 else if (isa<FunctionDecl>(*Mem)) 1815 DK = diag::err_anonymous_record_with_function; 1816 else if (isa<VarDecl>(*Mem)) 1817 DK = diag::err_anonymous_record_with_static; 1818 Diag((*Mem)->getLocation(), DK) 1819 << (int)Record->isUnion(); 1820 Invalid = true; 1821 } 1822 } 1823 } 1824 1825 if (!Record->isUnion() && !Owner->isRecord()) { 1826 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1827 << (int)getLangOptions().CPlusPlus; 1828 Invalid = true; 1829 } 1830 1831 // Mock up a declarator. 1832 Declarator Dc(DS, Declarator::TypeNameContext); 1833 TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S); 1834 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1835 1836 // Create a declaration for this anonymous struct/union. 1837 NamedDecl *Anon = 0; 1838 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1839 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1840 /*IdentifierInfo=*/0, 1841 Context.getTypeDeclType(Record), 1842 TInfo, 1843 /*BitWidth=*/0, /*Mutable=*/false); 1844 Anon->setAccess(AS); 1845 if (getLangOptions().CPlusPlus) { 1846 FieldCollector->Add(cast<FieldDecl>(Anon)); 1847 if (!cast<CXXRecordDecl>(Record)->isEmpty()) 1848 cast<CXXRecordDecl>(OwningClass)->setEmpty(false); 1849 } 1850 } else { 1851 DeclSpec::SCS SCSpec = DS.getStorageClassSpec(); 1852 assert(SCSpec != DeclSpec::SCS_typedef && 1853 "Parser allowed 'typedef' as storage class VarDecl."); 1854 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1855 if (SCSpec == DeclSpec::SCS_mutable) { 1856 // mutable can only appear on non-static class members, so it's always 1857 // an error here 1858 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1859 Invalid = true; 1860 SC = VarDecl::None; 1861 } 1862 SCSpec = DS.getStorageClassSpecAsWritten(); 1863 VarDecl::StorageClass SCAsWritten 1864 = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 1865 1866 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1867 /*IdentifierInfo=*/0, 1868 Context.getTypeDeclType(Record), 1869 TInfo, SC, SCAsWritten); 1870 } 1871 Anon->setImplicit(); 1872 1873 // Add the anonymous struct/union object to the current 1874 // context. We'll be referencing this object when we refer to one of 1875 // its members. 1876 Owner->addDecl(Anon); 1877 1878 // Inject the members of the anonymous struct/union into the owning 1879 // context and into the identifier resolver chain for name lookup 1880 // purposes. 1881 if (InjectAnonymousStructOrUnionMembers(*this, S, Owner, Record, AS)) 1882 Invalid = true; 1883 1884 // Mark this as an anonymous struct/union type. Note that we do not 1885 // do this until after we have already checked and injected the 1886 // members of this anonymous struct/union type, because otherwise 1887 // the members could be injected twice: once by DeclContext when it 1888 // builds its lookup table, and once by 1889 // InjectAnonymousStructOrUnionMembers. 1890 Record->setAnonymousStructOrUnion(true); 1891 1892 if (Invalid) 1893 Anon->setInvalidDecl(); 1894 1895 return DeclPtrTy::make(Anon); 1896} 1897 1898 1899/// GetNameForDeclarator - Determine the full declaration name for the 1900/// given Declarator. 1901DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1902 return GetNameFromUnqualifiedId(D.getName()); 1903} 1904 1905/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1906DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1907 switch (Name.getKind()) { 1908 case UnqualifiedId::IK_Identifier: 1909 return DeclarationName(Name.Identifier); 1910 1911 case UnqualifiedId::IK_OperatorFunctionId: 1912 return Context.DeclarationNames.getCXXOperatorName( 1913 Name.OperatorFunctionId.Operator); 1914 1915 case UnqualifiedId::IK_LiteralOperatorId: 1916 return Context.DeclarationNames.getCXXLiteralOperatorName( 1917 Name.Identifier); 1918 1919 case UnqualifiedId::IK_ConversionFunctionId: { 1920 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1921 if (Ty.isNull()) 1922 return DeclarationName(); 1923 1924 return Context.DeclarationNames.getCXXConversionFunctionName( 1925 Context.getCanonicalType(Ty)); 1926 } 1927 1928 case UnqualifiedId::IK_ConstructorName: { 1929 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1930 if (Ty.isNull()) 1931 return DeclarationName(); 1932 1933 return Context.DeclarationNames.getCXXConstructorName( 1934 Context.getCanonicalType(Ty)); 1935 } 1936 1937 case UnqualifiedId::IK_ConstructorTemplateId: { 1938 // In well-formed code, we can only have a constructor 1939 // template-id that refers to the current context, so go there 1940 // to find the actual type being constructed. 1941 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1942 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1943 return DeclarationName(); 1944 1945 // Determine the type of the class being constructed. 1946 QualType CurClassType = Context.getTypeDeclType(CurClass); 1947 1948 // FIXME: Check two things: that the template-id names the same type as 1949 // CurClassType, and that the template-id does not occur when the name 1950 // was qualified. 1951 1952 return Context.DeclarationNames.getCXXConstructorName( 1953 Context.getCanonicalType(CurClassType)); 1954 } 1955 1956 case UnqualifiedId::IK_DestructorName: { 1957 QualType Ty = GetTypeFromParser(Name.DestructorName); 1958 if (Ty.isNull()) 1959 return DeclarationName(); 1960 1961 return Context.DeclarationNames.getCXXDestructorName( 1962 Context.getCanonicalType(Ty)); 1963 } 1964 1965 case UnqualifiedId::IK_TemplateId: { 1966 TemplateName TName 1967 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1968 return Context.getNameForTemplate(TName); 1969 } 1970 } 1971 1972 assert(false && "Unknown name kind"); 1973 return DeclarationName(); 1974} 1975 1976/// isNearlyMatchingFunction - Determine whether the C++ functions 1977/// Declaration and Definition are "nearly" matching. This heuristic 1978/// is used to improve diagnostics in the case where an out-of-line 1979/// function definition doesn't match any declaration within 1980/// the class or namespace. 1981static bool isNearlyMatchingFunction(ASTContext &Context, 1982 FunctionDecl *Declaration, 1983 FunctionDecl *Definition) { 1984 if (Declaration->param_size() != Definition->param_size()) 1985 return false; 1986 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1987 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1988 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1989 1990 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1991 DefParamTy.getNonReferenceType())) 1992 return false; 1993 } 1994 1995 return true; 1996} 1997 1998/// NeedsRebuildingInCurrentInstantiation - Checks whether the given 1999/// declarator needs to be rebuilt in the current instantiation. 2000/// Any bits of declarator which appear before the name are valid for 2001/// consideration here. That's specifically the type in the decl spec 2002/// and the base type in any member-pointer chunks. 2003static bool RebuildDeclaratorInCurrentInstantiation(Sema &S, Declarator &D, 2004 DeclarationName Name) { 2005 // The types we specifically need to rebuild are: 2006 // - typenames, typeofs, and decltypes 2007 // - types which will become injected class names 2008 // Of course, we also need to rebuild any type referencing such a 2009 // type. It's safest to just say "dependent", but we call out a 2010 // few cases here. 2011 2012 DeclSpec &DS = D.getMutableDeclSpec(); 2013 switch (DS.getTypeSpecType()) { 2014 case DeclSpec::TST_typename: 2015 case DeclSpec::TST_typeofType: 2016 case DeclSpec::TST_typeofExpr: 2017 case DeclSpec::TST_decltype: { 2018 // Grab the type from the parser. 2019 TypeSourceInfo *TSI = 0; 2020 QualType T = S.GetTypeFromParser(DS.getTypeRep(), &TSI); 2021 if (T.isNull() || !T->isDependentType()) break; 2022 2023 // Make sure there's a type source info. This isn't really much 2024 // of a waste; most dependent types should have type source info 2025 // attached already. 2026 if (!TSI) 2027 TSI = S.Context.getTrivialTypeSourceInfo(T, DS.getTypeSpecTypeLoc()); 2028 2029 // Rebuild the type in the current instantiation. 2030 TSI = S.RebuildTypeInCurrentInstantiation(TSI, D.getIdentifierLoc(), Name); 2031 if (!TSI) return true; 2032 2033 // Store the new type back in the decl spec. 2034 QualType LocType = S.CreateLocInfoType(TSI->getType(), TSI); 2035 DS.UpdateTypeRep(LocType.getAsOpaquePtr()); 2036 break; 2037 } 2038 2039 default: 2040 // Nothing to do for these decl specs. 2041 break; 2042 } 2043 2044 // It doesn't matter what order we do this in. 2045 for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) { 2046 DeclaratorChunk &Chunk = D.getTypeObject(I); 2047 2048 // The only type information in the declarator which can come 2049 // before the declaration name is the base type of a member 2050 // pointer. 2051 if (Chunk.Kind != DeclaratorChunk::MemberPointer) 2052 continue; 2053 2054 // Rebuild the scope specifier in-place. 2055 CXXScopeSpec &SS = Chunk.Mem.Scope(); 2056 if (S.RebuildNestedNameSpecifierInCurrentInstantiation(SS)) 2057 return true; 2058 } 2059 2060 return false; 2061} 2062 2063Sema::DeclPtrTy 2064Sema::HandleDeclarator(Scope *S, Declarator &D, 2065 MultiTemplateParamsArg TemplateParamLists, 2066 bool IsFunctionDefinition) { 2067 DeclarationName Name = GetNameForDeclarator(D); 2068 2069 // All of these full declarators require an identifier. If it doesn't have 2070 // one, the ParsedFreeStandingDeclSpec action should be used. 2071 if (!Name) { 2072 if (!D.isInvalidType()) // Reject this if we think it is valid. 2073 Diag(D.getDeclSpec().getSourceRange().getBegin(), 2074 diag::err_declarator_need_ident) 2075 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 2076 return DeclPtrTy(); 2077 } 2078 2079 // The scope passed in may not be a decl scope. Zip up the scope tree until 2080 // we find one that is. 2081 while ((S->getFlags() & Scope::DeclScope) == 0 || 2082 (S->getFlags() & Scope::TemplateParamScope) != 0) 2083 S = S->getParent(); 2084 2085 DeclContext *DC = CurContext; 2086 if (D.getCXXScopeSpec().isInvalid()) 2087 D.setInvalidType(); 2088 else if (D.getCXXScopeSpec().isSet()) { 2089 bool EnteringContext = !D.getDeclSpec().isFriendSpecified(); 2090 DC = computeDeclContext(D.getCXXScopeSpec(), EnteringContext); 2091 if (!DC) { 2092 // If we could not compute the declaration context, it's because the 2093 // declaration context is dependent but does not refer to a class, 2094 // class template, or class template partial specialization. Complain 2095 // and return early, to avoid the coming semantic disaster. 2096 Diag(D.getIdentifierLoc(), 2097 diag::err_template_qualified_declarator_no_match) 2098 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 2099 << D.getCXXScopeSpec().getRange(); 2100 return DeclPtrTy(); 2101 } 2102 2103 bool IsDependentContext = DC->isDependentContext(); 2104 2105 if (!IsDependentContext && 2106 RequireCompleteDeclContext(D.getCXXScopeSpec(), DC)) 2107 return DeclPtrTy(); 2108 2109 if (isa<CXXRecordDecl>(DC) && !cast<CXXRecordDecl>(DC)->hasDefinition()) { 2110 Diag(D.getIdentifierLoc(), 2111 diag::err_member_def_undefined_record) 2112 << Name << DC << D.getCXXScopeSpec().getRange(); 2113 D.setInvalidType(); 2114 } 2115 2116 // Check whether we need to rebuild the type of the given 2117 // declaration in the current instantiation. 2118 if (EnteringContext && IsDependentContext && 2119 TemplateParamLists.size() != 0) { 2120 ContextRAII SavedContext(*this, DC); 2121 if (RebuildDeclaratorInCurrentInstantiation(*this, D, Name)) 2122 D.setInvalidType(); 2123 } 2124 } 2125 2126 NamedDecl *New; 2127 2128 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 2129 QualType R = TInfo->getType(); 2130 2131 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2132 ForRedeclaration); 2133 2134 // See if this is a redefinition of a variable in the same scope. 2135 if (!D.getCXXScopeSpec().isSet()) { 2136 bool IsLinkageLookup = false; 2137 2138 // If the declaration we're planning to build will be a function 2139 // or object with linkage, then look for another declaration with 2140 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 2141 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 2142 /* Do nothing*/; 2143 else if (R->isFunctionType()) { 2144 if (CurContext->isFunctionOrMethod() || 2145 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2146 IsLinkageLookup = true; 2147 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 2148 IsLinkageLookup = true; 2149 else if (CurContext->getLookupContext()->isTranslationUnit() && 2150 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 2151 IsLinkageLookup = true; 2152 2153 if (IsLinkageLookup) 2154 Previous.clear(LookupRedeclarationWithLinkage); 2155 2156 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 2157 } else { // Something like "int foo::x;" 2158 LookupQualifiedName(Previous, DC); 2159 2160 // Don't consider using declarations as previous declarations for 2161 // out-of-line members. 2162 RemoveUsingDecls(Previous); 2163 2164 // C++ 7.3.1.2p2: 2165 // Members (including explicit specializations of templates) of a named 2166 // namespace can also be defined outside that namespace by explicit 2167 // qualification of the name being defined, provided that the entity being 2168 // defined was already declared in the namespace and the definition appears 2169 // after the point of declaration in a namespace that encloses the 2170 // declarations namespace. 2171 // 2172 // Note that we only check the context at this point. We don't yet 2173 // have enough information to make sure that PrevDecl is actually 2174 // the declaration we want to match. For example, given: 2175 // 2176 // class X { 2177 // void f(); 2178 // void f(float); 2179 // }; 2180 // 2181 // void X::f(int) { } // ill-formed 2182 // 2183 // In this case, PrevDecl will point to the overload set 2184 // containing the two f's declared in X, but neither of them 2185 // matches. 2186 2187 // First check whether we named the global scope. 2188 if (isa<TranslationUnitDecl>(DC)) { 2189 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 2190 << Name << D.getCXXScopeSpec().getRange(); 2191 } else { 2192 DeclContext *Cur = CurContext; 2193 while (isa<LinkageSpecDecl>(Cur)) 2194 Cur = Cur->getParent(); 2195 if (!Cur->Encloses(DC)) { 2196 // The qualifying scope doesn't enclose the original declaration. 2197 // Emit diagnostic based on current scope. 2198 SourceLocation L = D.getIdentifierLoc(); 2199 SourceRange R = D.getCXXScopeSpec().getRange(); 2200 if (isa<FunctionDecl>(Cur)) 2201 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2202 else 2203 Diag(L, diag::err_invalid_declarator_scope) 2204 << Name << cast<NamedDecl>(DC) << R; 2205 D.setInvalidType(); 2206 } 2207 } 2208 } 2209 2210 if (Previous.isSingleResult() && 2211 Previous.getFoundDecl()->isTemplateParameter()) { 2212 // Maybe we will complain about the shadowed template parameter. 2213 if (!D.isInvalidType()) 2214 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2215 Previous.getFoundDecl())) 2216 D.setInvalidType(); 2217 2218 // Just pretend that we didn't see the previous declaration. 2219 Previous.clear(); 2220 } 2221 2222 // In C++, the previous declaration we find might be a tag type 2223 // (class or enum). In this case, the new declaration will hide the 2224 // tag type. Note that this does does not apply if we're declaring a 2225 // typedef (C++ [dcl.typedef]p4). 2226 if (Previous.isSingleTagDecl() && 2227 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2228 Previous.clear(); 2229 2230 bool Redeclaration = false; 2231 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2232 if (TemplateParamLists.size()) { 2233 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2234 return DeclPtrTy(); 2235 } 2236 2237 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2238 } else if (R->isFunctionType()) { 2239 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2240 move(TemplateParamLists), 2241 IsFunctionDefinition, Redeclaration); 2242 } else { 2243 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2244 move(TemplateParamLists), 2245 Redeclaration); 2246 } 2247 2248 if (New == 0) 2249 return DeclPtrTy(); 2250 2251 // If this has an identifier and is not an invalid redeclaration or 2252 // function template specialization, add it to the scope stack. 2253 if (New->getDeclName() && !(Redeclaration && New->isInvalidDecl())) 2254 PushOnScopeChains(New, S); 2255 2256 return DeclPtrTy::make(New); 2257} 2258 2259/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2260/// types into constant array types in certain situations which would otherwise 2261/// be errors (for GCC compatibility). 2262static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2263 ASTContext &Context, 2264 bool &SizeIsNegative) { 2265 // This method tries to turn a variable array into a constant 2266 // array even when the size isn't an ICE. This is necessary 2267 // for compatibility with code that depends on gcc's buggy 2268 // constant expression folding, like struct {char x[(int)(char*)2];} 2269 SizeIsNegative = false; 2270 2271 QualifierCollector Qs; 2272 const Type *Ty = Qs.strip(T); 2273 2274 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2275 QualType Pointee = PTy->getPointeeType(); 2276 QualType FixedType = 2277 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2278 if (FixedType.isNull()) return FixedType; 2279 FixedType = Context.getPointerType(FixedType); 2280 return Qs.apply(FixedType); 2281 } 2282 2283 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2284 if (!VLATy) 2285 return QualType(); 2286 // FIXME: We should probably handle this case 2287 if (VLATy->getElementType()->isVariablyModifiedType()) 2288 return QualType(); 2289 2290 Expr::EvalResult EvalResult; 2291 if (!VLATy->getSizeExpr() || 2292 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2293 !EvalResult.Val.isInt()) 2294 return QualType(); 2295 2296 llvm::APSInt &Res = EvalResult.Val.getInt(); 2297 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2298 // TODO: preserve the size expression in declarator info 2299 return Context.getConstantArrayType(VLATy->getElementType(), 2300 Res, ArrayType::Normal, 0); 2301 } 2302 2303 SizeIsNegative = true; 2304 return QualType(); 2305} 2306 2307/// \brief Register the given locally-scoped external C declaration so 2308/// that it can be found later for redeclarations 2309void 2310Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2311 const LookupResult &Previous, 2312 Scope *S) { 2313 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2314 "Decl is not a locally-scoped decl!"); 2315 // Note that we have a locally-scoped external with this name. 2316 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2317 2318 if (!Previous.isSingleResult()) 2319 return; 2320 2321 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2322 2323 // If there was a previous declaration of this variable, it may be 2324 // in our identifier chain. Update the identifier chain with the new 2325 // declaration. 2326 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2327 // The previous declaration was found on the identifer resolver 2328 // chain, so remove it from its scope. 2329 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2330 S = S->getParent(); 2331 2332 if (S) 2333 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2334 } 2335} 2336 2337/// \brief Diagnose function specifiers on a declaration of an identifier that 2338/// does not identify a function. 2339void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2340 // FIXME: We should probably indicate the identifier in question to avoid 2341 // confusion for constructs like "inline int a(), b;" 2342 if (D.getDeclSpec().isInlineSpecified()) 2343 Diag(D.getDeclSpec().getInlineSpecLoc(), 2344 diag::err_inline_non_function); 2345 2346 if (D.getDeclSpec().isVirtualSpecified()) 2347 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2348 diag::err_virtual_non_function); 2349 2350 if (D.getDeclSpec().isExplicitSpecified()) 2351 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2352 diag::err_explicit_non_function); 2353} 2354 2355NamedDecl* 2356Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2357 QualType R, TypeSourceInfo *TInfo, 2358 LookupResult &Previous, bool &Redeclaration) { 2359 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2360 if (D.getCXXScopeSpec().isSet()) { 2361 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2362 << D.getCXXScopeSpec().getRange(); 2363 D.setInvalidType(); 2364 // Pretend we didn't see the scope specifier. 2365 DC = CurContext; 2366 Previous.clear(); 2367 } 2368 2369 if (getLangOptions().CPlusPlus) { 2370 // Check that there are no default arguments (C++ only). 2371 CheckExtraCXXDefaultArguments(D); 2372 } 2373 2374 DiagnoseFunctionSpecifiers(D); 2375 2376 if (D.getDeclSpec().isThreadSpecified()) 2377 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2378 2379 if (D.getName().Kind != UnqualifiedId::IK_Identifier) { 2380 Diag(D.getName().StartLocation, diag::err_typedef_not_identifier) 2381 << D.getName().getSourceRange(); 2382 return 0; 2383 } 2384 2385 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2386 if (!NewTD) return 0; 2387 2388 // Handle attributes prior to checking for duplicates in MergeVarDecl 2389 ProcessDeclAttributes(S, NewTD, D); 2390 2391 // Merge the decl with the existing one if appropriate. If the decl is 2392 // in an outer scope, it isn't the same thing. 2393 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2394 if (!Previous.empty()) { 2395 Redeclaration = true; 2396 MergeTypeDefDecl(NewTD, Previous); 2397 } 2398 2399 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2400 // then it shall have block scope. 2401 QualType T = NewTD->getUnderlyingType(); 2402 if (T->isVariablyModifiedType()) { 2403 FunctionNeedsScopeChecking() = true; 2404 2405 if (S->getFnParent() == 0) { 2406 bool SizeIsNegative; 2407 QualType FixedTy = 2408 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2409 if (!FixedTy.isNull()) { 2410 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2411 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2412 } else { 2413 if (SizeIsNegative) 2414 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2415 else if (T->isVariableArrayType()) 2416 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2417 else 2418 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2419 NewTD->setInvalidDecl(); 2420 } 2421 } 2422 } 2423 2424 // If this is the C FILE type, notify the AST context. 2425 if (IdentifierInfo *II = NewTD->getIdentifier()) 2426 if (!NewTD->isInvalidDecl() && 2427 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2428 if (II->isStr("FILE")) 2429 Context.setFILEDecl(NewTD); 2430 else if (II->isStr("jmp_buf")) 2431 Context.setjmp_bufDecl(NewTD); 2432 else if (II->isStr("sigjmp_buf")) 2433 Context.setsigjmp_bufDecl(NewTD); 2434 } 2435 2436 return NewTD; 2437} 2438 2439/// \brief Determines whether the given declaration is an out-of-scope 2440/// previous declaration. 2441/// 2442/// This routine should be invoked when name lookup has found a 2443/// previous declaration (PrevDecl) that is not in the scope where a 2444/// new declaration by the same name is being introduced. If the new 2445/// declaration occurs in a local scope, previous declarations with 2446/// linkage may still be considered previous declarations (C99 2447/// 6.2.2p4-5, C++ [basic.link]p6). 2448/// 2449/// \param PrevDecl the previous declaration found by name 2450/// lookup 2451/// 2452/// \param DC the context in which the new declaration is being 2453/// declared. 2454/// 2455/// \returns true if PrevDecl is an out-of-scope previous declaration 2456/// for a new delcaration with the same name. 2457static bool 2458isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2459 ASTContext &Context) { 2460 if (!PrevDecl) 2461 return 0; 2462 2463 if (!PrevDecl->hasLinkage()) 2464 return false; 2465 2466 if (Context.getLangOptions().CPlusPlus) { 2467 // C++ [basic.link]p6: 2468 // If there is a visible declaration of an entity with linkage 2469 // having the same name and type, ignoring entities declared 2470 // outside the innermost enclosing namespace scope, the block 2471 // scope declaration declares that same entity and receives the 2472 // linkage of the previous declaration. 2473 DeclContext *OuterContext = DC->getLookupContext(); 2474 if (!OuterContext->isFunctionOrMethod()) 2475 // This rule only applies to block-scope declarations. 2476 return false; 2477 else { 2478 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2479 if (PrevOuterContext->isRecord()) 2480 // We found a member function: ignore it. 2481 return false; 2482 else { 2483 // Find the innermost enclosing namespace for the new and 2484 // previous declarations. 2485 while (!OuterContext->isFileContext()) 2486 OuterContext = OuterContext->getParent(); 2487 while (!PrevOuterContext->isFileContext()) 2488 PrevOuterContext = PrevOuterContext->getParent(); 2489 2490 // The previous declaration is in a different namespace, so it 2491 // isn't the same function. 2492 if (OuterContext->getPrimaryContext() != 2493 PrevOuterContext->getPrimaryContext()) 2494 return false; 2495 } 2496 } 2497 } 2498 2499 return true; 2500} 2501 2502static void SetNestedNameSpecifier(DeclaratorDecl *DD, Declarator &D) { 2503 CXXScopeSpec &SS = D.getCXXScopeSpec(); 2504 if (!SS.isSet()) return; 2505 DD->setQualifierInfo(static_cast<NestedNameSpecifier*>(SS.getScopeRep()), 2506 SS.getRange()); 2507} 2508 2509NamedDecl* 2510Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2511 QualType R, TypeSourceInfo *TInfo, 2512 LookupResult &Previous, 2513 MultiTemplateParamsArg TemplateParamLists, 2514 bool &Redeclaration) { 2515 DeclarationName Name = GetNameForDeclarator(D); 2516 2517 // Check that there are no default arguments (C++ only). 2518 if (getLangOptions().CPlusPlus) 2519 CheckExtraCXXDefaultArguments(D); 2520 2521 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpec(); 2522 assert(SCSpec != DeclSpec::SCS_typedef && 2523 "Parser allowed 'typedef' as storage class VarDecl."); 2524 VarDecl::StorageClass SC = StorageClassSpecToVarDeclStorageClass(SCSpec, 0); 2525 if (SCSpec == DeclSpec::SCS_mutable) { 2526 // mutable can only appear on non-static class members, so it's always 2527 // an error here 2528 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2529 D.setInvalidType(); 2530 SC = VarDecl::None; 2531 } 2532 SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 2533 VarDecl::StorageClass SCAsWritten 2534 = StorageClassSpecToVarDeclStorageClass(SCSpec, DC); 2535 2536 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2537 if (!II) { 2538 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2539 << Name.getAsString(); 2540 return 0; 2541 } 2542 2543 DiagnoseFunctionSpecifiers(D); 2544 2545 if (!DC->isRecord() && S->getFnParent() == 0) { 2546 // C99 6.9p2: The storage-class specifiers auto and register shall not 2547 // appear in the declaration specifiers in an external declaration. 2548 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2549 2550 // If this is a register variable with an asm label specified, then this 2551 // is a GNU extension. 2552 if (SC == VarDecl::Register && D.getAsmLabel()) 2553 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2554 else 2555 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2556 D.setInvalidType(); 2557 } 2558 } 2559 if (DC->isRecord() && !CurContext->isRecord()) { 2560 // This is an out-of-line definition of a static data member. 2561 if (SC == VarDecl::Static) { 2562 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2563 diag::err_static_out_of_line) 2564 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 2565 } else if (SC == VarDecl::None) 2566 SC = VarDecl::Static; 2567 } 2568 if (SC == VarDecl::Static) { 2569 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2570 if (RD->isLocalClass()) 2571 Diag(D.getIdentifierLoc(), 2572 diag::err_static_data_member_not_allowed_in_local_class) 2573 << Name << RD->getDeclName(); 2574 } 2575 } 2576 2577 // Match up the template parameter lists with the scope specifier, then 2578 // determine whether we have a template or a template specialization. 2579 bool isExplicitSpecialization = false; 2580 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 2581 bool Invalid = false; 2582 if (TemplateParameterList *TemplateParams 2583 = MatchTemplateParametersToScopeSpecifier( 2584 D.getDeclSpec().getSourceRange().getBegin(), 2585 D.getCXXScopeSpec(), 2586 (TemplateParameterList**)TemplateParamLists.get(), 2587 TemplateParamLists.size(), 2588 /*never a friend*/ false, 2589 isExplicitSpecialization, 2590 Invalid)) { 2591 // All but one template parameter lists have been matching. 2592 --NumMatchedTemplateParamLists; 2593 2594 if (TemplateParams->size() > 0) { 2595 // There is no such thing as a variable template. 2596 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2597 << II 2598 << SourceRange(TemplateParams->getTemplateLoc(), 2599 TemplateParams->getRAngleLoc()); 2600 return 0; 2601 } else { 2602 // There is an extraneous 'template<>' for this variable. Complain 2603 // about it, but allow the declaration of the variable. 2604 Diag(TemplateParams->getTemplateLoc(), 2605 diag::err_template_variable_noparams) 2606 << II 2607 << SourceRange(TemplateParams->getTemplateLoc(), 2608 TemplateParams->getRAngleLoc()); 2609 2610 isExplicitSpecialization = true; 2611 } 2612 } 2613 2614 VarDecl *NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2615 II, R, TInfo, SC, SCAsWritten); 2616 2617 if (D.isInvalidType() || Invalid) 2618 NewVD->setInvalidDecl(); 2619 2620 SetNestedNameSpecifier(NewVD, D); 2621 2622 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 2623 NewVD->setTemplateParameterListsInfo(Context, 2624 NumMatchedTemplateParamLists, 2625 (TemplateParameterList**)TemplateParamLists.release()); 2626 } 2627 2628 if (D.getDeclSpec().isThreadSpecified()) { 2629 if (NewVD->hasLocalStorage()) 2630 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2631 else if (!Context.Target.isTLSSupported()) 2632 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2633 else 2634 NewVD->setThreadSpecified(true); 2635 } 2636 2637 // Set the lexical context. If the declarator has a C++ scope specifier, the 2638 // lexical context will be different from the semantic context. 2639 NewVD->setLexicalDeclContext(CurContext); 2640 2641 // Handle attributes prior to checking for duplicates in MergeVarDecl 2642 ProcessDeclAttributes(S, NewVD, D); 2643 2644 // Handle GNU asm-label extension (encoded as an attribute). 2645 if (Expr *E = (Expr*) D.getAsmLabel()) { 2646 // The parser guarantees this is a string. 2647 StringLiteral *SE = cast<StringLiteral>(E); 2648 NewVD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 2649 } 2650 2651 // Diagnose shadowed variables before filtering for scope. 2652 if (!D.getCXXScopeSpec().isSet()) 2653 CheckShadow(S, NewVD, Previous); 2654 2655 // Don't consider existing declarations that are in a different 2656 // scope and are out-of-semantic-context declarations (if the new 2657 // declaration has linkage). 2658 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2659 2660 // Merge the decl with the existing one if appropriate. 2661 if (!Previous.empty()) { 2662 if (Previous.isSingleResult() && 2663 isa<FieldDecl>(Previous.getFoundDecl()) && 2664 D.getCXXScopeSpec().isSet()) { 2665 // The user tried to define a non-static data member 2666 // out-of-line (C++ [dcl.meaning]p1). 2667 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2668 << D.getCXXScopeSpec().getRange(); 2669 Previous.clear(); 2670 NewVD->setInvalidDecl(); 2671 } 2672 } else if (D.getCXXScopeSpec().isSet()) { 2673 // No previous declaration in the qualifying scope. 2674 Diag(D.getIdentifierLoc(), diag::err_no_member) 2675 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2676 << D.getCXXScopeSpec().getRange(); 2677 NewVD->setInvalidDecl(); 2678 } 2679 2680 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2681 2682 // This is an explicit specialization of a static data member. Check it. 2683 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2684 CheckMemberSpecialization(NewVD, Previous)) 2685 NewVD->setInvalidDecl(); 2686 2687 // attributes declared post-definition are currently ignored 2688 if (Previous.isSingleResult()) { 2689 VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2690 if (Def && (Def = Def->getDefinition()) && 2691 Def != NewVD && D.hasAttributes()) { 2692 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2693 Diag(Def->getLocation(), diag::note_previous_definition); 2694 } 2695 } 2696 2697 // If this is a locally-scoped extern C variable, update the map of 2698 // such variables. 2699 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2700 !NewVD->isInvalidDecl()) 2701 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2702 2703 return NewVD; 2704} 2705 2706/// \brief Diagnose variable or built-in function shadowing. Implements 2707/// -Wshadow. 2708/// 2709/// This method is called whenever a VarDecl is added to a "useful" 2710/// scope. 2711/// 2712/// \param S the scope in which the shadowing name is being declared 2713/// \param R the lookup of the name 2714/// 2715void Sema::CheckShadow(Scope *S, VarDecl *D, const LookupResult& R) { 2716 // Return if warning is ignored. 2717 if (Diags.getDiagnosticLevel(diag::warn_decl_shadow) == Diagnostic::Ignored) 2718 return; 2719 2720 // Don't diagnose declarations at file scope. The scope might not 2721 // have a DeclContext if (e.g.) we're parsing a function prototype. 2722 DeclContext *NewDC = static_cast<DeclContext*>(S->getEntity()); 2723 if (NewDC && NewDC->isFileContext()) 2724 return; 2725 2726 // Only diagnose if we're shadowing an unambiguous field or variable. 2727 if (R.getResultKind() != LookupResult::Found) 2728 return; 2729 2730 NamedDecl* ShadowedDecl = R.getFoundDecl(); 2731 if (!isa<VarDecl>(ShadowedDecl) && !isa<FieldDecl>(ShadowedDecl)) 2732 return; 2733 2734 DeclContext *OldDC = ShadowedDecl->getDeclContext(); 2735 2736 // Only warn about certain kinds of shadowing for class members. 2737 if (NewDC && NewDC->isRecord()) { 2738 // In particular, don't warn about shadowing non-class members. 2739 if (!OldDC->isRecord()) 2740 return; 2741 2742 // TODO: should we warn about static data members shadowing 2743 // static data members from base classes? 2744 2745 // TODO: don't diagnose for inaccessible shadowed members. 2746 // This is hard to do perfectly because we might friend the 2747 // shadowing context, but that's just a false negative. 2748 } 2749 2750 // Determine what kind of declaration we're shadowing. 2751 unsigned Kind; 2752 if (isa<RecordDecl>(OldDC)) { 2753 if (isa<FieldDecl>(ShadowedDecl)) 2754 Kind = 3; // field 2755 else 2756 Kind = 2; // static data member 2757 } else if (OldDC->isFileContext()) 2758 Kind = 1; // global 2759 else 2760 Kind = 0; // local 2761 2762 DeclarationName Name = R.getLookupName(); 2763 2764 // Emit warning and note. 2765 Diag(R.getNameLoc(), diag::warn_decl_shadow) << Name << Kind << OldDC; 2766 Diag(ShadowedDecl->getLocation(), diag::note_previous_declaration); 2767} 2768 2769/// \brief Check -Wshadow without the advantage of a previous lookup. 2770void Sema::CheckShadow(Scope *S, VarDecl *D) { 2771 LookupResult R(*this, D->getDeclName(), D->getLocation(), 2772 Sema::LookupOrdinaryName, Sema::ForRedeclaration); 2773 LookupName(R, S); 2774 CheckShadow(S, D, R); 2775} 2776 2777/// \brief Perform semantic checking on a newly-created variable 2778/// declaration. 2779/// 2780/// This routine performs all of the type-checking required for a 2781/// variable declaration once it has been built. It is used both to 2782/// check variables after they have been parsed and their declarators 2783/// have been translated into a declaration, and to check variables 2784/// that have been instantiated from a template. 2785/// 2786/// Sets NewVD->isInvalidDecl() if an error was encountered. 2787void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2788 LookupResult &Previous, 2789 bool &Redeclaration) { 2790 // If the decl is already known invalid, don't check it. 2791 if (NewVD->isInvalidDecl()) 2792 return; 2793 2794 QualType T = NewVD->getType(); 2795 2796 if (T->isObjCObjectType()) { 2797 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2798 return NewVD->setInvalidDecl(); 2799 } 2800 2801 // Emit an error if an address space was applied to decl with local storage. 2802 // This includes arrays of objects with address space qualifiers, but not 2803 // automatic variables that point to other address spaces. 2804 // ISO/IEC TR 18037 S5.1.2 2805 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2806 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2807 return NewVD->setInvalidDecl(); 2808 } 2809 2810 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2811 && !NewVD->hasAttr<BlocksAttr>()) 2812 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2813 2814 bool isVM = T->isVariablyModifiedType(); 2815 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2816 NewVD->hasAttr<BlocksAttr>() || 2817 // FIXME: We need to diagnose jumps passed initialized variables in C++. 2818 // However, this turns on the scope checker for everything with a variable 2819 // which may impact compile time. See if we can find a better solution 2820 // to this, perhaps only checking functions that contain gotos in C++? 2821 (LangOpts.CPlusPlus && NewVD->hasLocalStorage())) 2822 FunctionNeedsScopeChecking() = true; 2823 2824 if ((isVM && NewVD->hasLinkage()) || 2825 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2826 bool SizeIsNegative; 2827 QualType FixedTy = 2828 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2829 2830 if (FixedTy.isNull() && T->isVariableArrayType()) { 2831 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2832 // FIXME: This won't give the correct result for 2833 // int a[10][n]; 2834 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2835 2836 if (NewVD->isFileVarDecl()) 2837 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2838 << SizeRange; 2839 else if (NewVD->getStorageClass() == VarDecl::Static) 2840 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2841 << SizeRange; 2842 else 2843 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2844 << SizeRange; 2845 return NewVD->setInvalidDecl(); 2846 } 2847 2848 if (FixedTy.isNull()) { 2849 if (NewVD->isFileVarDecl()) 2850 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2851 else 2852 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2853 return NewVD->setInvalidDecl(); 2854 } 2855 2856 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2857 NewVD->setType(FixedTy); 2858 } 2859 2860 if (Previous.empty() && NewVD->isExternC()) { 2861 // Since we did not find anything by this name and we're declaring 2862 // an extern "C" variable, look for a non-visible extern "C" 2863 // declaration with the same name. 2864 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2865 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2866 if (Pos != LocallyScopedExternalDecls.end()) 2867 Previous.addDecl(Pos->second); 2868 } 2869 2870 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2871 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2872 << T; 2873 return NewVD->setInvalidDecl(); 2874 } 2875 2876 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2877 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2878 return NewVD->setInvalidDecl(); 2879 } 2880 2881 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2882 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2883 return NewVD->setInvalidDecl(); 2884 } 2885 2886 // Function pointers and references cannot have qualified function type, only 2887 // function pointer-to-members can do that. 2888 QualType Pointee; 2889 unsigned PtrOrRef = 0; 2890 if (const PointerType *Ptr = T->getAs<PointerType>()) 2891 Pointee = Ptr->getPointeeType(); 2892 else if (const ReferenceType *Ref = T->getAs<ReferenceType>()) { 2893 Pointee = Ref->getPointeeType(); 2894 PtrOrRef = 1; 2895 } 2896 if (!Pointee.isNull() && Pointee->isFunctionProtoType() && 2897 Pointee->getAs<FunctionProtoType>()->getTypeQuals() != 0) { 2898 Diag(NewVD->getLocation(), diag::err_invalid_qualified_function_pointer) 2899 << PtrOrRef; 2900 return NewVD->setInvalidDecl(); 2901 } 2902 2903 if (!Previous.empty()) { 2904 Redeclaration = true; 2905 MergeVarDecl(NewVD, Previous); 2906 } 2907} 2908 2909/// \brief Data used with FindOverriddenMethod 2910struct FindOverriddenMethodData { 2911 Sema *S; 2912 CXXMethodDecl *Method; 2913}; 2914 2915/// \brief Member lookup function that determines whether a given C++ 2916/// method overrides a method in a base class, to be used with 2917/// CXXRecordDecl::lookupInBases(). 2918static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2919 CXXBasePath &Path, 2920 void *UserData) { 2921 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2922 2923 FindOverriddenMethodData *Data 2924 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2925 2926 DeclarationName Name = Data->Method->getDeclName(); 2927 2928 // FIXME: Do we care about other names here too? 2929 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2930 // We really want to find the base class destructor here. 2931 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2932 CanQualType CT = Data->S->Context.getCanonicalType(T); 2933 2934 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2935 } 2936 2937 for (Path.Decls = BaseRecord->lookup(Name); 2938 Path.Decls.first != Path.Decls.second; 2939 ++Path.Decls.first) { 2940 NamedDecl *D = *Path.Decls.first; 2941 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 2942 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, false)) 2943 return true; 2944 } 2945 } 2946 2947 return false; 2948} 2949 2950/// AddOverriddenMethods - See if a method overrides any in the base classes, 2951/// and if so, check that it's a valid override and remember it. 2952void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2953 // Look for virtual methods in base classes that this method might override. 2954 CXXBasePaths Paths; 2955 FindOverriddenMethodData Data; 2956 Data.Method = MD; 2957 Data.S = this; 2958 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2959 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2960 E = Paths.found_decls_end(); I != E; ++I) { 2961 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2962 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2963 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2964 !CheckOverridingFunctionAttributes(MD, OldMD)) 2965 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2966 } 2967 } 2968 } 2969} 2970 2971NamedDecl* 2972Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2973 QualType R, TypeSourceInfo *TInfo, 2974 LookupResult &Previous, 2975 MultiTemplateParamsArg TemplateParamLists, 2976 bool IsFunctionDefinition, bool &Redeclaration) { 2977 assert(R.getTypePtr()->isFunctionType()); 2978 2979 DeclarationName Name = GetNameForDeclarator(D); 2980 FunctionDecl::StorageClass SC = FunctionDecl::None; 2981 switch (D.getDeclSpec().getStorageClassSpec()) { 2982 default: assert(0 && "Unknown storage class!"); 2983 case DeclSpec::SCS_auto: 2984 case DeclSpec::SCS_register: 2985 case DeclSpec::SCS_mutable: 2986 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2987 diag::err_typecheck_sclass_func); 2988 D.setInvalidType(); 2989 break; 2990 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2991 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2992 case DeclSpec::SCS_static: { 2993 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2994 // C99 6.7.1p5: 2995 // The declaration of an identifier for a function that has 2996 // block scope shall have no explicit storage-class specifier 2997 // other than extern 2998 // See also (C++ [dcl.stc]p4). 2999 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3000 diag::err_static_block_func); 3001 SC = FunctionDecl::None; 3002 } else 3003 SC = FunctionDecl::Static; 3004 break; 3005 } 3006 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 3007 } 3008 3009 if (D.getDeclSpec().isThreadSpecified()) 3010 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3011 3012 bool isFriend = D.getDeclSpec().isFriendSpecified(); 3013 bool isInline = D.getDeclSpec().isInlineSpecified(); 3014 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 3015 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 3016 3017 DeclSpec::SCS SCSpec = D.getDeclSpec().getStorageClassSpecAsWritten(); 3018 FunctionDecl::StorageClass SCAsWritten 3019 = StorageClassSpecToFunctionDeclStorageClass(SCSpec, DC); 3020 3021 // Check that the return type is not an abstract class type. 3022 // For record types, this is done by the AbstractClassUsageDiagnoser once 3023 // the class has been completely parsed. 3024 if (!DC->isRecord() && 3025 RequireNonAbstractType(D.getIdentifierLoc(), 3026 R->getAs<FunctionType>()->getResultType(), 3027 diag::err_abstract_type_in_decl, 3028 AbstractReturnType)) 3029 D.setInvalidType(); 3030 3031 // Do not allow returning a objc interface by-value. 3032 if (R->getAs<FunctionType>()->getResultType()->isObjCObjectType()) { 3033 Diag(D.getIdentifierLoc(), 3034 diag::err_object_cannot_be_passed_returned_by_value) << 0 3035 << R->getAs<FunctionType>()->getResultType(); 3036 D.setInvalidType(); 3037 } 3038 3039 bool isVirtualOkay = false; 3040 FunctionDecl *NewFD; 3041 3042 if (isFriend) { 3043 // C++ [class.friend]p5 3044 // A function can be defined in a friend declaration of a 3045 // class . . . . Such a function is implicitly inline. 3046 isInline |= IsFunctionDefinition; 3047 } 3048 3049 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 3050 // This is a C++ constructor declaration. 3051 assert(DC->isRecord() && 3052 "Constructors can only be declared in a member context"); 3053 3054 R = CheckConstructorDeclarator(D, R, SC); 3055 3056 // Create the new declaration 3057 NewFD = CXXConstructorDecl::Create(Context, 3058 cast<CXXRecordDecl>(DC), 3059 D.getIdentifierLoc(), Name, R, TInfo, 3060 isExplicit, isInline, 3061 /*isImplicitlyDeclared=*/false); 3062 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 3063 // This is a C++ destructor declaration. 3064 if (DC->isRecord()) { 3065 R = CheckDestructorDeclarator(D, R, SC); 3066 3067 NewFD = CXXDestructorDecl::Create(Context, 3068 cast<CXXRecordDecl>(DC), 3069 D.getIdentifierLoc(), Name, R, 3070 isInline, 3071 /*isImplicitlyDeclared=*/false); 3072 NewFD->setTypeSourceInfo(TInfo); 3073 3074 isVirtualOkay = true; 3075 } else { 3076 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 3077 3078 // Create a FunctionDecl to satisfy the function definition parsing 3079 // code path. 3080 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 3081 Name, R, TInfo, SC, SCAsWritten, isInline, 3082 /*hasPrototype=*/true); 3083 D.setInvalidType(); 3084 } 3085 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 3086 if (!DC->isRecord()) { 3087 Diag(D.getIdentifierLoc(), 3088 diag::err_conv_function_not_member); 3089 return 0; 3090 } 3091 3092 CheckConversionDeclarator(D, R, SC); 3093 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 3094 D.getIdentifierLoc(), Name, R, TInfo, 3095 isInline, isExplicit); 3096 3097 isVirtualOkay = true; 3098 } else if (DC->isRecord()) { 3099 // If the of the function is the same as the name of the record, then this 3100 // must be an invalid constructor that has a return type. 3101 // (The parser checks for a return type and makes the declarator a 3102 // constructor if it has no return type). 3103 // must have an invalid constructor that has a return type 3104 if (Name.getAsIdentifierInfo() && 3105 Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 3106 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 3107 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 3108 << SourceRange(D.getIdentifierLoc()); 3109 return 0; 3110 } 3111 3112 bool isStatic = SC == FunctionDecl::Static; 3113 3114 // [class.free]p1: 3115 // Any allocation function for a class T is a static member 3116 // (even if not explicitly declared static). 3117 if (Name.getCXXOverloadedOperator() == OO_New || 3118 Name.getCXXOverloadedOperator() == OO_Array_New) 3119 isStatic = true; 3120 3121 // [class.free]p6 Any deallocation function for a class X is a static member 3122 // (even if not explicitly declared static). 3123 if (Name.getCXXOverloadedOperator() == OO_Delete || 3124 Name.getCXXOverloadedOperator() == OO_Array_Delete) 3125 isStatic = true; 3126 3127 // This is a C++ method declaration. 3128 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 3129 D.getIdentifierLoc(), Name, R, TInfo, 3130 isStatic, SCAsWritten, isInline); 3131 3132 isVirtualOkay = !isStatic; 3133 } else { 3134 // Determine whether the function was written with a 3135 // prototype. This true when: 3136 // - we're in C++ (where every function has a prototype), 3137 // - there is a prototype in the declarator, or 3138 // - the type R of the function is some kind of typedef or other reference 3139 // to a type name (which eventually refers to a function type). 3140 bool HasPrototype = 3141 getLangOptions().CPlusPlus || 3142 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 3143 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 3144 3145 NewFD = FunctionDecl::Create(Context, DC, 3146 D.getIdentifierLoc(), 3147 Name, R, TInfo, SC, SCAsWritten, isInline, 3148 HasPrototype); 3149 } 3150 3151 if (D.isInvalidType()) 3152 NewFD->setInvalidDecl(); 3153 3154 SetNestedNameSpecifier(NewFD, D); 3155 3156 // Set the lexical context. If the declarator has a C++ 3157 // scope specifier, or is the object of a friend declaration, the 3158 // lexical context will be different from the semantic context. 3159 NewFD->setLexicalDeclContext(CurContext); 3160 3161 // Match up the template parameter lists with the scope specifier, then 3162 // determine whether we have a template or a template specialization. 3163 FunctionTemplateDecl *FunctionTemplate = 0; 3164 bool isExplicitSpecialization = false; 3165 bool isFunctionTemplateSpecialization = false; 3166 unsigned NumMatchedTemplateParamLists = TemplateParamLists.size(); 3167 bool Invalid = false; 3168 if (TemplateParameterList *TemplateParams 3169 = MatchTemplateParametersToScopeSpecifier( 3170 D.getDeclSpec().getSourceRange().getBegin(), 3171 D.getCXXScopeSpec(), 3172 (TemplateParameterList**)TemplateParamLists.get(), 3173 TemplateParamLists.size(), 3174 isFriend, 3175 isExplicitSpecialization, 3176 Invalid)) { 3177 // All but one template parameter lists have been matching. 3178 --NumMatchedTemplateParamLists; 3179 3180 if (TemplateParams->size() > 0) { 3181 // This is a function template 3182 3183 // Check that we can declare a template here. 3184 if (CheckTemplateDeclScope(S, TemplateParams)) 3185 return 0; 3186 3187 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 3188 NewFD->getLocation(), 3189 Name, TemplateParams, 3190 NewFD); 3191 FunctionTemplate->setLexicalDeclContext(CurContext); 3192 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 3193 } else { 3194 // This is a function template specialization. 3195 isFunctionTemplateSpecialization = true; 3196 3197 // C++0x [temp.expl.spec]p20 forbids "template<> friend void foo(int);". 3198 if (isFriend && isFunctionTemplateSpecialization) { 3199 // We want to remove the "template<>", found here. 3200 SourceRange RemoveRange = TemplateParams->getSourceRange(); 3201 3202 // If we remove the template<> and the name is not a 3203 // template-id, we're actually silently creating a problem: 3204 // the friend declaration will refer to an untemplated decl, 3205 // and clearly the user wants a template specialization. So 3206 // we need to insert '<>' after the name. 3207 SourceLocation InsertLoc; 3208 if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) { 3209 InsertLoc = D.getName().getSourceRange().getEnd(); 3210 InsertLoc = PP.getLocForEndOfToken(InsertLoc); 3211 } 3212 3213 Diag(D.getIdentifierLoc(), diag::err_template_spec_decl_friend) 3214 << Name << RemoveRange 3215 << FixItHint::CreateRemoval(RemoveRange) 3216 << FixItHint::CreateInsertion(InsertLoc, "<>"); 3217 } 3218 } 3219 } 3220 3221 if (NumMatchedTemplateParamLists > 0 && D.getCXXScopeSpec().isSet()) { 3222 NewFD->setTemplateParameterListsInfo(Context, 3223 NumMatchedTemplateParamLists, 3224 (TemplateParameterList**)TemplateParamLists.release()); 3225 } 3226 3227 if (Invalid) { 3228 NewFD->setInvalidDecl(); 3229 if (FunctionTemplate) 3230 FunctionTemplate->setInvalidDecl(); 3231 } 3232 3233 // C++ [dcl.fct.spec]p5: 3234 // The virtual specifier shall only be used in declarations of 3235 // nonstatic class member functions that appear within a 3236 // member-specification of a class declaration; see 10.3. 3237 // 3238 if (isVirtual && !NewFD->isInvalidDecl()) { 3239 if (!isVirtualOkay) { 3240 Diag(D.getDeclSpec().getVirtualSpecLoc(), 3241 diag::err_virtual_non_function); 3242 } else if (!CurContext->isRecord()) { 3243 // 'virtual' was specified outside of the class. 3244 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 3245 << FixItHint::CreateRemoval(D.getDeclSpec().getVirtualSpecLoc()); 3246 } else { 3247 // Okay: Add virtual to the method. 3248 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 3249 CurClass->setMethodAsVirtual(NewFD); 3250 } 3251 } 3252 3253 // C++ [dcl.fct.spec]p6: 3254 // The explicit specifier shall be used only in the declaration of a 3255 // constructor or conversion function within its class definition; see 12.3.1 3256 // and 12.3.2. 3257 if (isExplicit && !NewFD->isInvalidDecl()) { 3258 if (!CurContext->isRecord()) { 3259 // 'explicit' was specified outside of the class. 3260 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3261 diag::err_explicit_out_of_class) 3262 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3263 } else if (!isa<CXXConstructorDecl>(NewFD) && 3264 !isa<CXXConversionDecl>(NewFD)) { 3265 // 'explicit' was specified on a function that wasn't a constructor 3266 // or conversion function. 3267 Diag(D.getDeclSpec().getExplicitSpecLoc(), 3268 diag::err_explicit_non_ctor_or_conv_function) 3269 << FixItHint::CreateRemoval(D.getDeclSpec().getExplicitSpecLoc()); 3270 } 3271 } 3272 3273 // Filter out previous declarations that don't match the scope. 3274 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 3275 3276 if (isFriend) { 3277 // DC is the namespace in which the function is being declared. 3278 assert((DC->isFileContext() || !Previous.empty()) && 3279 "previously-undeclared friend function being created " 3280 "in a non-namespace context"); 3281 3282 // For now, claim that the objects have no previous declaration. 3283 if (FunctionTemplate) { 3284 FunctionTemplate->setObjectOfFriendDecl(false); 3285 FunctionTemplate->setAccess(AS_public); 3286 } 3287 NewFD->setObjectOfFriendDecl(false); 3288 NewFD->setAccess(AS_public); 3289 } 3290 3291 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 3292 !CurContext->isRecord()) { 3293 // C++ [class.static]p1: 3294 // A data or function member of a class may be declared static 3295 // in a class definition, in which case it is a static member of 3296 // the class. 3297 3298 // Complain about the 'static' specifier if it's on an out-of-line 3299 // member function definition. 3300 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 3301 diag::err_static_out_of_line) 3302 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc()); 3303 } 3304 3305 // Handle GNU asm-label extension (encoded as an attribute). 3306 if (Expr *E = (Expr*) D.getAsmLabel()) { 3307 // The parser guarantees this is a string. 3308 StringLiteral *SE = cast<StringLiteral>(E); 3309 NewFD->addAttr(::new (Context) AsmLabelAttr(Context, SE->getString())); 3310 } 3311 3312 // Copy the parameter declarations from the declarator D to the function 3313 // declaration NewFD, if they are available. First scavenge them into Params. 3314 llvm::SmallVector<ParmVarDecl*, 16> Params; 3315 if (D.getNumTypeObjects() > 0) { 3316 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3317 3318 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 3319 // function that takes no arguments, not a function that takes a 3320 // single void argument. 3321 // We let through "const void" here because Sema::GetTypeForDeclarator 3322 // already checks for that case. 3323 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 3324 FTI.ArgInfo[0].Param && 3325 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 3326 // Empty arg list, don't push any params. 3327 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 3328 3329 // In C++, the empty parameter-type-list must be spelled "void"; a 3330 // typedef of void is not permitted. 3331 if (getLangOptions().CPlusPlus && 3332 Param->getType().getUnqualifiedType() != Context.VoidTy) 3333 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 3334 // FIXME: Leaks decl? 3335 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 3336 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 3337 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 3338 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 3339 Param->setDeclContext(NewFD); 3340 Params.push_back(Param); 3341 3342 if (Param->isInvalidDecl()) 3343 NewFD->setInvalidDecl(); 3344 } 3345 } 3346 3347 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 3348 // When we're declaring a function with a typedef, typeof, etc as in the 3349 // following example, we'll need to synthesize (unnamed) 3350 // parameters for use in the declaration. 3351 // 3352 // @code 3353 // typedef void fn(int); 3354 // fn f; 3355 // @endcode 3356 3357 // Synthesize a parameter for each argument type. 3358 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 3359 AE = FT->arg_type_end(); AI != AE; ++AI) { 3360 ParmVarDecl *Param = 3361 BuildParmVarDeclForTypedef(NewFD, D.getIdentifierLoc(), *AI); 3362 Params.push_back(Param); 3363 } 3364 } else { 3365 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 3366 "Should not need args for typedef of non-prototype fn"); 3367 } 3368 // Finally, we know we have the right number of parameters, install them. 3369 NewFD->setParams(Params.data(), Params.size()); 3370 3371 // If the declarator is a template-id, translate the parser's template 3372 // argument list into our AST format. 3373 bool HasExplicitTemplateArgs = false; 3374 TemplateArgumentListInfo TemplateArgs; 3375 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 3376 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 3377 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 3378 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 3379 ASTTemplateArgsPtr TemplateArgsPtr(*this, 3380 TemplateId->getTemplateArgs(), 3381 TemplateId->NumArgs); 3382 translateTemplateArguments(TemplateArgsPtr, 3383 TemplateArgs); 3384 TemplateArgsPtr.release(); 3385 3386 HasExplicitTemplateArgs = true; 3387 3388 if (FunctionTemplate) { 3389 // FIXME: Diagnose function template with explicit template 3390 // arguments. 3391 HasExplicitTemplateArgs = false; 3392 } else if (!isFunctionTemplateSpecialization && 3393 !D.getDeclSpec().isFriendSpecified()) { 3394 // We have encountered something that the user meant to be a 3395 // specialization (because it has explicitly-specified template 3396 // arguments) but that was not introduced with a "template<>" (or had 3397 // too few of them). 3398 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3399 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3400 << FixItHint::CreateInsertion( 3401 D.getDeclSpec().getSourceRange().getBegin(), 3402 "template<> "); 3403 isFunctionTemplateSpecialization = true; 3404 } else { 3405 // "friend void foo<>(int);" is an implicit specialization decl. 3406 isFunctionTemplateSpecialization = true; 3407 } 3408 } else if (isFriend && isFunctionTemplateSpecialization) { 3409 // This combination is only possible in a recovery case; the user 3410 // wrote something like: 3411 // template <> friend void foo(int); 3412 // which we're recovering from as if the user had written: 3413 // friend void foo<>(int); 3414 // Go ahead and fake up a template id. 3415 HasExplicitTemplateArgs = true; 3416 TemplateArgs.setLAngleLoc(D.getIdentifierLoc()); 3417 TemplateArgs.setRAngleLoc(D.getIdentifierLoc()); 3418 } 3419 3420 // If it's a friend (and only if it's a friend), it's possible 3421 // that either the specialized function type or the specialized 3422 // template is dependent, and therefore matching will fail. In 3423 // this case, don't check the specialization yet. 3424 if (isFunctionTemplateSpecialization && isFriend && 3425 (NewFD->getType()->isDependentType() || DC->isDependentContext())) { 3426 assert(HasExplicitTemplateArgs && 3427 "friend function specialization without template args"); 3428 if (CheckDependentFunctionTemplateSpecialization(NewFD, TemplateArgs, 3429 Previous)) 3430 NewFD->setInvalidDecl(); 3431 } else if (isFunctionTemplateSpecialization) { 3432 if (CheckFunctionTemplateSpecialization(NewFD, 3433 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3434 Previous)) 3435 NewFD->setInvalidDecl(); 3436 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD)) { 3437 if (CheckMemberSpecialization(NewFD, Previous)) 3438 NewFD->setInvalidDecl(); 3439 } 3440 3441 // Perform semantic checking on the function declaration. 3442 bool OverloadableAttrRequired = false; // FIXME: HACK! 3443 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3444 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3445 3446 assert((NewFD->isInvalidDecl() || !Redeclaration || 3447 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3448 "previous declaration set still overloaded"); 3449 3450 NamedDecl *PrincipalDecl = (FunctionTemplate 3451 ? cast<NamedDecl>(FunctionTemplate) 3452 : NewFD); 3453 3454 if (isFriend && Redeclaration) { 3455 AccessSpecifier Access = AS_public; 3456 if (!NewFD->isInvalidDecl()) 3457 Access = NewFD->getPreviousDeclaration()->getAccess(); 3458 3459 NewFD->setAccess(Access); 3460 if (FunctionTemplate) FunctionTemplate->setAccess(Access); 3461 3462 PrincipalDecl->setObjectOfFriendDecl(true); 3463 } 3464 3465 if (NewFD->isOverloadedOperator() && !DC->isRecord() && 3466 PrincipalDecl->isInIdentifierNamespace(Decl::IDNS_Ordinary)) 3467 PrincipalDecl->setNonMemberOperator(); 3468 3469 // If we have a function template, check the template parameter 3470 // list. This will check and merge default template arguments. 3471 if (FunctionTemplate) { 3472 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3473 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3474 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3475 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3476 : TPC_FunctionTemplate); 3477 } 3478 3479 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3480 // Fake up an access specifier if it's supposed to be a class member. 3481 if (!Redeclaration && isa<CXXRecordDecl>(NewFD->getDeclContext())) 3482 NewFD->setAccess(AS_public); 3483 3484 // An out-of-line member function declaration must also be a 3485 // definition (C++ [dcl.meaning]p1). 3486 // Note that this is not the case for explicit specializations of 3487 // function templates or member functions of class templates, per 3488 // C++ [temp.expl.spec]p2. We also allow these declarations as an extension 3489 // for compatibility with old SWIG code which likes to generate them. 3490 if (!IsFunctionDefinition && !isFriend && 3491 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3492 Diag(NewFD->getLocation(), diag::ext_out_of_line_declaration) 3493 << D.getCXXScopeSpec().getRange(); 3494 } 3495 if (!Redeclaration && !(isFriend && CurContext->isDependentContext())) { 3496 // The user tried to provide an out-of-line definition for a 3497 // function that is a member of a class or namespace, but there 3498 // was no such member function declared (C++ [class.mfct]p2, 3499 // C++ [namespace.memdef]p2). For example: 3500 // 3501 // class X { 3502 // void f() const; 3503 // }; 3504 // 3505 // void X::f() { } // ill-formed 3506 // 3507 // Complain about this problem, and attempt to suggest close 3508 // matches (e.g., those that differ only in cv-qualifiers and 3509 // whether the parameter types are references). 3510 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3511 << Name << DC << D.getCXXScopeSpec().getRange(); 3512 NewFD->setInvalidDecl(); 3513 3514 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3515 ForRedeclaration); 3516 LookupQualifiedName(Prev, DC); 3517 assert(!Prev.isAmbiguous() && 3518 "Cannot have an ambiguity in previous-declaration lookup"); 3519 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3520 Func != FuncEnd; ++Func) { 3521 if (isa<FunctionDecl>(*Func) && 3522 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3523 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3524 } 3525 } 3526 } 3527 3528 // Handle attributes. We need to have merged decls when handling attributes 3529 // (for example to check for conflicts, etc). 3530 // FIXME: This needs to happen before we merge declarations. Then, 3531 // let attribute merging cope with attribute conflicts. 3532 ProcessDeclAttributes(S, NewFD, D); 3533 3534 // attributes declared post-definition are currently ignored 3535 if (Redeclaration && Previous.isSingleResult()) { 3536 const FunctionDecl *Def; 3537 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3538 if (PrevFD && PrevFD->hasBody(Def) && D.hasAttributes()) { 3539 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3540 Diag(Def->getLocation(), diag::note_previous_definition); 3541 } 3542 } 3543 3544 AddKnownFunctionAttributes(NewFD); 3545 3546 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3547 // If a function name is overloadable in C, then every function 3548 // with that name must be marked "overloadable". 3549 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3550 << Redeclaration << NewFD; 3551 if (!Previous.empty()) 3552 Diag(Previous.getRepresentativeDecl()->getLocation(), 3553 diag::note_attribute_overloadable_prev_overload); 3554 NewFD->addAttr(::new (Context) OverloadableAttr()); 3555 } 3556 3557 // If this is a locally-scoped extern C function, update the 3558 // map of such names. 3559 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3560 && !NewFD->isInvalidDecl()) 3561 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3562 3563 // Set this FunctionDecl's range up to the right paren. 3564 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3565 3566 if (FunctionTemplate && NewFD->isInvalidDecl()) 3567 FunctionTemplate->setInvalidDecl(); 3568 3569 if (FunctionTemplate) 3570 return FunctionTemplate; 3571 3572 3573 // Keep track of static, non-inlined function definitions that 3574 // have not been used. We will warn later. 3575 // FIXME: Also include static functions declared but not defined. 3576 if (!NewFD->isInvalidDecl() && IsFunctionDefinition 3577 && !NewFD->isInlined() && NewFD->getLinkage() == InternalLinkage 3578 && !NewFD->isUsed() && !NewFD->hasAttr<UnusedAttr>() 3579 && !NewFD->hasAttr<ConstructorAttr>() 3580 && !NewFD->hasAttr<DestructorAttr>()) 3581 UnusedStaticFuncs.push_back(NewFD); 3582 3583 return NewFD; 3584} 3585 3586/// \brief Perform semantic checking of a new function declaration. 3587/// 3588/// Performs semantic analysis of the new function declaration 3589/// NewFD. This routine performs all semantic checking that does not 3590/// require the actual declarator involved in the declaration, and is 3591/// used both for the declaration of functions as they are parsed 3592/// (called via ActOnDeclarator) and for the declaration of functions 3593/// that have been instantiated via C++ template instantiation (called 3594/// via InstantiateDecl). 3595/// 3596/// \param IsExplicitSpecialiation whether this new function declaration is 3597/// an explicit specialization of the previous declaration. 3598/// 3599/// This sets NewFD->isInvalidDecl() to true if there was an error. 3600void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3601 LookupResult &Previous, 3602 bool IsExplicitSpecialization, 3603 bool &Redeclaration, 3604 bool &OverloadableAttrRequired) { 3605 // If NewFD is already known erroneous, don't do any of this checking. 3606 if (NewFD->isInvalidDecl()) 3607 return; 3608 3609 if (NewFD->getResultType()->isVariablyModifiedType()) { 3610 // Functions returning a variably modified type violate C99 6.7.5.2p2 3611 // because all functions have linkage. 3612 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3613 return NewFD->setInvalidDecl(); 3614 } 3615 3616 if (NewFD->isMain()) 3617 CheckMain(NewFD); 3618 3619 // Check for a previous declaration of this name. 3620 if (Previous.empty() && NewFD->isExternC()) { 3621 // Since we did not find anything by this name and we're declaring 3622 // an extern "C" function, look for a non-visible extern "C" 3623 // declaration with the same name. 3624 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3625 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3626 if (Pos != LocallyScopedExternalDecls.end()) 3627 Previous.addDecl(Pos->second); 3628 } 3629 3630 // Merge or overload the declaration with an existing declaration of 3631 // the same name, if appropriate. 3632 if (!Previous.empty()) { 3633 // Determine whether NewFD is an overload of PrevDecl or 3634 // a declaration that requires merging. If it's an overload, 3635 // there's no more work to do here; we'll just add the new 3636 // function to the scope. 3637 3638 NamedDecl *OldDecl = 0; 3639 if (!AllowOverloadingOfFunction(Previous, Context)) { 3640 Redeclaration = true; 3641 OldDecl = Previous.getFoundDecl(); 3642 } else { 3643 if (!getLangOptions().CPlusPlus) { 3644 OverloadableAttrRequired = true; 3645 3646 // Functions marked "overloadable" must have a prototype (that 3647 // we can't get through declaration merging). 3648 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3649 Diag(NewFD->getLocation(), 3650 diag::err_attribute_overloadable_no_prototype) 3651 << NewFD; 3652 Redeclaration = true; 3653 3654 // Turn this into a variadic function with no parameters. 3655 QualType R = Context.getFunctionType( 3656 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3657 0, 0, true, 0, false, false, 0, 0, 3658 FunctionType::ExtInfo()); 3659 NewFD->setType(R); 3660 return NewFD->setInvalidDecl(); 3661 } 3662 } 3663 3664 switch (CheckOverload(S, NewFD, Previous, OldDecl, 3665 /*NewIsUsingDecl*/ false)) { 3666 case Ovl_Match: 3667 Redeclaration = true; 3668 break; 3669 3670 case Ovl_NonFunction: 3671 Redeclaration = true; 3672 break; 3673 3674 case Ovl_Overload: 3675 Redeclaration = false; 3676 break; 3677 } 3678 } 3679 3680 if (Redeclaration) { 3681 // NewFD and OldDecl represent declarations that need to be 3682 // merged. 3683 if (MergeFunctionDecl(NewFD, OldDecl)) 3684 return NewFD->setInvalidDecl(); 3685 3686 Previous.clear(); 3687 Previous.addDecl(OldDecl); 3688 3689 if (FunctionTemplateDecl *OldTemplateDecl 3690 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3691 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3692 FunctionTemplateDecl *NewTemplateDecl 3693 = NewFD->getDescribedFunctionTemplate(); 3694 assert(NewTemplateDecl && "Template/non-template mismatch"); 3695 if (CXXMethodDecl *Method 3696 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3697 Method->setAccess(OldTemplateDecl->getAccess()); 3698 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3699 } 3700 3701 // If this is an explicit specialization of a member that is a function 3702 // template, mark it as a member specialization. 3703 if (IsExplicitSpecialization && 3704 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3705 NewTemplateDecl->setMemberSpecialization(); 3706 assert(OldTemplateDecl->isMemberSpecialization()); 3707 } 3708 } else { 3709 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3710 NewFD->setAccess(OldDecl->getAccess()); 3711 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3712 } 3713 } 3714 } 3715 3716 // Semantic checking for this function declaration (in isolation). 3717 if (getLangOptions().CPlusPlus) { 3718 // C++-specific checks. 3719 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3720 CheckConstructor(Constructor); 3721 } else if (CXXDestructorDecl *Destructor = 3722 dyn_cast<CXXDestructorDecl>(NewFD)) { 3723 CXXRecordDecl *Record = Destructor->getParent(); 3724 QualType ClassType = Context.getTypeDeclType(Record); 3725 3726 // FIXME: Shouldn't we be able to perform this check even when the class 3727 // type is dependent? Both gcc and edg can handle that. 3728 if (!ClassType->isDependentType()) { 3729 DeclarationName Name 3730 = Context.DeclarationNames.getCXXDestructorName( 3731 Context.getCanonicalType(ClassType)); 3732 if (NewFD->getDeclName() != Name) { 3733 Diag(NewFD->getLocation(), diag::err_destructor_name); 3734 return NewFD->setInvalidDecl(); 3735 } 3736 } 3737 3738 Record->setUserDeclaredDestructor(true); 3739 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3740 // user-defined destructor. 3741 Record->setPOD(false); 3742 3743 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3744 // declared destructor. 3745 // FIXME: C++0x: don't do this for "= default" destructors 3746 Record->setHasTrivialDestructor(false); 3747 } else if (CXXConversionDecl *Conversion 3748 = dyn_cast<CXXConversionDecl>(NewFD)) { 3749 ActOnConversionDeclarator(Conversion); 3750 } 3751 3752 // Find any virtual functions that this function overrides. 3753 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3754 if (!Method->isFunctionTemplateSpecialization() && 3755 !Method->getDescribedFunctionTemplate()) 3756 AddOverriddenMethods(Method->getParent(), Method); 3757 } 3758 3759 // Additional checks for the destructor; make sure we do this after we 3760 // figure out whether the destructor is virtual. 3761 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3762 if (!Destructor->getParent()->isDependentType()) 3763 CheckDestructor(Destructor); 3764 3765 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3766 if (NewFD->isOverloadedOperator() && 3767 CheckOverloadedOperatorDeclaration(NewFD)) 3768 return NewFD->setInvalidDecl(); 3769 3770 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3771 if (NewFD->getLiteralIdentifier() && 3772 CheckLiteralOperatorDeclaration(NewFD)) 3773 return NewFD->setInvalidDecl(); 3774 3775 // In C++, check default arguments now that we have merged decls. Unless 3776 // the lexical context is the class, because in this case this is done 3777 // during delayed parsing anyway. 3778 if (!CurContext->isRecord()) 3779 CheckCXXDefaultArguments(NewFD); 3780 } 3781} 3782 3783void Sema::CheckMain(FunctionDecl* FD) { 3784 // C++ [basic.start.main]p3: A program that declares main to be inline 3785 // or static is ill-formed. 3786 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3787 // shall not appear in a declaration of main. 3788 // static main is not an error under C99, but we should warn about it. 3789 bool isInline = FD->isInlineSpecified(); 3790 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3791 if (isInline || isStatic) { 3792 unsigned diagID = diag::warn_unusual_main_decl; 3793 if (isInline || getLangOptions().CPlusPlus) 3794 diagID = diag::err_unusual_main_decl; 3795 3796 int which = isStatic + (isInline << 1) - 1; 3797 Diag(FD->getLocation(), diagID) << which; 3798 } 3799 3800 QualType T = FD->getType(); 3801 assert(T->isFunctionType() && "function decl is not of function type"); 3802 const FunctionType* FT = T->getAs<FunctionType>(); 3803 3804 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3805 // TODO: add a replacement fixit to turn the return type into 'int'. 3806 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3807 FD->setInvalidDecl(true); 3808 } 3809 3810 // Treat protoless main() as nullary. 3811 if (isa<FunctionNoProtoType>(FT)) return; 3812 3813 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3814 unsigned nparams = FTP->getNumArgs(); 3815 assert(FD->getNumParams() == nparams); 3816 3817 bool HasExtraParameters = (nparams > 3); 3818 3819 // Darwin passes an undocumented fourth argument of type char**. If 3820 // other platforms start sprouting these, the logic below will start 3821 // getting shifty. 3822 if (nparams == 4 && 3823 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3824 HasExtraParameters = false; 3825 3826 if (HasExtraParameters) { 3827 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3828 FD->setInvalidDecl(true); 3829 nparams = 3; 3830 } 3831 3832 // FIXME: a lot of the following diagnostics would be improved 3833 // if we had some location information about types. 3834 3835 QualType CharPP = 3836 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3837 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3838 3839 for (unsigned i = 0; i < nparams; ++i) { 3840 QualType AT = FTP->getArgType(i); 3841 3842 bool mismatch = true; 3843 3844 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3845 mismatch = false; 3846 else if (Expected[i] == CharPP) { 3847 // As an extension, the following forms are okay: 3848 // char const ** 3849 // char const * const * 3850 // char * const * 3851 3852 QualifierCollector qs; 3853 const PointerType* PT; 3854 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3855 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3856 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3857 qs.removeConst(); 3858 mismatch = !qs.empty(); 3859 } 3860 } 3861 3862 if (mismatch) { 3863 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3864 // TODO: suggest replacing given type with expected type 3865 FD->setInvalidDecl(true); 3866 } 3867 } 3868 3869 if (nparams == 1 && !FD->isInvalidDecl()) { 3870 Diag(FD->getLocation(), diag::warn_main_one_arg); 3871 } 3872} 3873 3874bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3875 // FIXME: Need strict checking. In C89, we need to check for 3876 // any assignment, increment, decrement, function-calls, or 3877 // commas outside of a sizeof. In C99, it's the same list, 3878 // except that the aforementioned are allowed in unevaluated 3879 // expressions. Everything else falls under the 3880 // "may accept other forms of constant expressions" exception. 3881 // (We never end up here for C++, so the constant expression 3882 // rules there don't matter.) 3883 if (Init->isConstantInitializer(Context)) 3884 return false; 3885 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3886 << Init->getSourceRange(); 3887 return true; 3888} 3889 3890void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3891 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3892} 3893 3894/// AddInitializerToDecl - Adds the initializer Init to the 3895/// declaration dcl. If DirectInit is true, this is C++ direct 3896/// initialization rather than copy initialization. 3897void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3898 Decl *RealDecl = dcl.getAs<Decl>(); 3899 // If there is no declaration, there was an error parsing it. Just ignore 3900 // the initializer. 3901 if (RealDecl == 0) 3902 return; 3903 3904 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3905 // With declarators parsed the way they are, the parser cannot 3906 // distinguish between a normal initializer and a pure-specifier. 3907 // Thus this grotesque test. 3908 IntegerLiteral *IL; 3909 Expr *Init = static_cast<Expr *>(init.get()); 3910 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3911 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3912 CheckPureMethod(Method, Init->getSourceRange()); 3913 else { 3914 Diag(Method->getLocation(), diag::err_member_function_initialization) 3915 << Method->getDeclName() << Init->getSourceRange(); 3916 Method->setInvalidDecl(); 3917 } 3918 return; 3919 } 3920 3921 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3922 if (!VDecl) { 3923 if (getLangOptions().CPlusPlus && 3924 RealDecl->getLexicalDeclContext()->isRecord() && 3925 isa<NamedDecl>(RealDecl)) 3926 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3927 << cast<NamedDecl>(RealDecl)->getDeclName(); 3928 else 3929 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3930 RealDecl->setInvalidDecl(); 3931 return; 3932 } 3933 3934 // A definition must end up with a complete type, which means it must be 3935 // complete with the restriction that an array type might be completed by the 3936 // initializer; note that later code assumes this restriction. 3937 QualType BaseDeclType = VDecl->getType(); 3938 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3939 BaseDeclType = Array->getElementType(); 3940 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3941 diag::err_typecheck_decl_incomplete_type)) { 3942 RealDecl->setInvalidDecl(); 3943 return; 3944 } 3945 3946 // The variable can not have an abstract class type. 3947 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3948 diag::err_abstract_type_in_decl, 3949 AbstractVariableType)) 3950 VDecl->setInvalidDecl(); 3951 3952 const VarDecl *Def; 3953 if ((Def = VDecl->getDefinition()) && Def != VDecl) { 3954 Diag(VDecl->getLocation(), diag::err_redefinition) 3955 << VDecl->getDeclName(); 3956 Diag(Def->getLocation(), diag::note_previous_definition); 3957 VDecl->setInvalidDecl(); 3958 return; 3959 } 3960 3961 // Take ownership of the expression, now that we're sure we have somewhere 3962 // to put it. 3963 Expr *Init = init.takeAs<Expr>(); 3964 assert(Init && "missing initializer"); 3965 3966 // Capture the variable that is being initialized and the style of 3967 // initialization. 3968 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3969 3970 // FIXME: Poor source location information. 3971 InitializationKind Kind 3972 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3973 Init->getLocStart(), 3974 Init->getLocEnd()) 3975 : InitializationKind::CreateCopy(VDecl->getLocation(), 3976 Init->getLocStart()); 3977 3978 // Get the decls type and save a reference for later, since 3979 // CheckInitializerTypes may change it. 3980 QualType DclT = VDecl->getType(), SavT = DclT; 3981 if (VDecl->isBlockVarDecl()) { 3982 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3983 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3984 VDecl->setInvalidDecl(); 3985 } else if (!VDecl->isInvalidDecl()) { 3986 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3987 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3988 MultiExprArg(*this, (void**)&Init, 1), 3989 &DclT); 3990 if (Result.isInvalid()) { 3991 VDecl->setInvalidDecl(); 3992 return; 3993 } 3994 3995 Init = Result.takeAs<Expr>(); 3996 3997 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3998 // Don't check invalid declarations to avoid emitting useless diagnostics. 3999 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4000 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 4001 CheckForConstantInitializer(Init, DclT); 4002 } 4003 } 4004 } else if (VDecl->isStaticDataMember() && 4005 VDecl->getLexicalDeclContext()->isRecord()) { 4006 // This is an in-class initialization for a static data member, e.g., 4007 // 4008 // struct S { 4009 // static const int value = 17; 4010 // }; 4011 4012 // Attach the initializer 4013 VDecl->setInit(Init); 4014 4015 // C++ [class.mem]p4: 4016 // A member-declarator can contain a constant-initializer only 4017 // if it declares a static member (9.4) of const integral or 4018 // const enumeration type, see 9.4.2. 4019 QualType T = VDecl->getType(); 4020 if (!T->isDependentType() && 4021 (!Context.getCanonicalType(T).isConstQualified() || 4022 !T->isIntegralOrEnumerationType())) { 4023 Diag(VDecl->getLocation(), diag::err_member_initialization) 4024 << VDecl->getDeclName() << Init->getSourceRange(); 4025 VDecl->setInvalidDecl(); 4026 } else { 4027 // C++ [class.static.data]p4: 4028 // If a static data member is of const integral or const 4029 // enumeration type, its declaration in the class definition 4030 // can specify a constant-initializer which shall be an 4031 // integral constant expression (5.19). 4032 if (!Init->isTypeDependent() && 4033 !Init->getType()->isIntegralOrEnumerationType()) { 4034 // We have a non-dependent, non-integral or enumeration type. 4035 Diag(Init->getSourceRange().getBegin(), 4036 diag::err_in_class_initializer_non_integral_type) 4037 << Init->getType() << Init->getSourceRange(); 4038 VDecl->setInvalidDecl(); 4039 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 4040 // Check whether the expression is a constant expression. 4041 llvm::APSInt Value; 4042 SourceLocation Loc; 4043 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 4044 Diag(Loc, diag::err_in_class_initializer_non_constant) 4045 << Init->getSourceRange(); 4046 VDecl->setInvalidDecl(); 4047 } else if (!VDecl->getType()->isDependentType()) 4048 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 4049 } 4050 } 4051 } else if (VDecl->isFileVarDecl()) { 4052 if (VDecl->getStorageClass() == VarDecl::Extern && 4053 (!getLangOptions().CPlusPlus || 4054 !Context.getBaseElementType(VDecl->getType()).isConstQualified())) 4055 Diag(VDecl->getLocation(), diag::warn_extern_init); 4056 if (!VDecl->isInvalidDecl()) { 4057 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 4058 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 4059 MultiExprArg(*this, (void**)&Init, 1), 4060 &DclT); 4061 if (Result.isInvalid()) { 4062 VDecl->setInvalidDecl(); 4063 return; 4064 } 4065 4066 Init = Result.takeAs<Expr>(); 4067 } 4068 4069 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 4070 // Don't check invalid declarations to avoid emitting useless diagnostics. 4071 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 4072 // C99 6.7.8p4. All file scoped initializers need to be constant. 4073 CheckForConstantInitializer(Init, DclT); 4074 } 4075 } 4076 // If the type changed, it means we had an incomplete type that was 4077 // completed by the initializer. For example: 4078 // int ary[] = { 1, 3, 5 }; 4079 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 4080 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 4081 VDecl->setType(DclT); 4082 Init->setType(DclT); 4083 } 4084 4085 Init = MaybeCreateCXXExprWithTemporaries(Init); 4086 // Attach the initializer to the decl. 4087 VDecl->setInit(Init); 4088 4089 if (getLangOptions().CPlusPlus) { 4090 // Make sure we mark the destructor as used if necessary. 4091 QualType InitType = VDecl->getType(); 4092 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 4093 InitType = Context.getBaseElementType(Array); 4094 if (const RecordType *Record = InitType->getAs<RecordType>()) 4095 FinalizeVarWithDestructor(VDecl, Record); 4096 } 4097 4098 return; 4099} 4100 4101/// ActOnInitializerError - Given that there was an error parsing an 4102/// initializer for the given declaration, try to return to some form 4103/// of sanity. 4104void Sema::ActOnInitializerError(DeclPtrTy dcl) { 4105 // Our main concern here is re-establishing invariants like "a 4106 // variable's type is either dependent or complete". 4107 Decl *D = dcl.getAs<Decl>(); 4108 if (!D || D->isInvalidDecl()) return; 4109 4110 VarDecl *VD = dyn_cast<VarDecl>(D); 4111 if (!VD) return; 4112 4113 QualType Ty = VD->getType(); 4114 if (Ty->isDependentType()) return; 4115 4116 // Require a complete type. 4117 if (RequireCompleteType(VD->getLocation(), 4118 Context.getBaseElementType(Ty), 4119 diag::err_typecheck_decl_incomplete_type)) { 4120 VD->setInvalidDecl(); 4121 return; 4122 } 4123 4124 // Require an abstract type. 4125 if (RequireNonAbstractType(VD->getLocation(), Ty, 4126 diag::err_abstract_type_in_decl, 4127 AbstractVariableType)) { 4128 VD->setInvalidDecl(); 4129 return; 4130 } 4131 4132 // Don't bother complaining about constructors or destructors, 4133 // though. 4134} 4135 4136void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 4137 bool TypeContainsUndeducedAuto) { 4138 Decl *RealDecl = dcl.getAs<Decl>(); 4139 4140 // If there is no declaration, there was an error parsing it. Just ignore it. 4141 if (RealDecl == 0) 4142 return; 4143 4144 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 4145 QualType Type = Var->getType(); 4146 4147 // C++0x [dcl.spec.auto]p3 4148 if (TypeContainsUndeducedAuto) { 4149 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 4150 << Var->getDeclName() << Type; 4151 Var->setInvalidDecl(); 4152 return; 4153 } 4154 4155 switch (Var->isThisDeclarationADefinition()) { 4156 case VarDecl::Definition: 4157 if (!Var->isStaticDataMember() || !Var->getAnyInitializer()) 4158 break; 4159 4160 // We have an out-of-line definition of a static data member 4161 // that has an in-class initializer, so we type-check this like 4162 // a declaration. 4163 // 4164 // Fall through 4165 4166 case VarDecl::DeclarationOnly: 4167 // It's only a declaration. 4168 4169 // Block scope. C99 6.7p7: If an identifier for an object is 4170 // declared with no linkage (C99 6.2.2p6), the type for the 4171 // object shall be complete. 4172 if (!Type->isDependentType() && Var->isBlockVarDecl() && 4173 !Var->getLinkage() && !Var->isInvalidDecl() && 4174 RequireCompleteType(Var->getLocation(), Type, 4175 diag::err_typecheck_decl_incomplete_type)) 4176 Var->setInvalidDecl(); 4177 4178 // Make sure that the type is not abstract. 4179 if (!Type->isDependentType() && !Var->isInvalidDecl() && 4180 RequireNonAbstractType(Var->getLocation(), Type, 4181 diag::err_abstract_type_in_decl, 4182 AbstractVariableType)) 4183 Var->setInvalidDecl(); 4184 return; 4185 4186 case VarDecl::TentativeDefinition: 4187 // File scope. C99 6.9.2p2: A declaration of an identifier for an 4188 // object that has file scope without an initializer, and without a 4189 // storage-class specifier or with the storage-class specifier "static", 4190 // constitutes a tentative definition. Note: A tentative definition with 4191 // external linkage is valid (C99 6.2.2p5). 4192 if (!Var->isInvalidDecl()) { 4193 if (const IncompleteArrayType *ArrayT 4194 = Context.getAsIncompleteArrayType(Type)) { 4195 if (RequireCompleteType(Var->getLocation(), 4196 ArrayT->getElementType(), 4197 diag::err_illegal_decl_array_incomplete_type)) 4198 Var->setInvalidDecl(); 4199 } else if (Var->getStorageClass() == VarDecl::Static) { 4200 // C99 6.9.2p3: If the declaration of an identifier for an object is 4201 // a tentative definition and has internal linkage (C99 6.2.2p3), the 4202 // declared type shall not be an incomplete type. 4203 // NOTE: code such as the following 4204 // static struct s; 4205 // struct s { int a; }; 4206 // is accepted by gcc. Hence here we issue a warning instead of 4207 // an error and we do not invalidate the static declaration. 4208 // NOTE: to avoid multiple warnings, only check the first declaration. 4209 if (Var->getPreviousDeclaration() == 0) 4210 RequireCompleteType(Var->getLocation(), Type, 4211 diag::ext_typecheck_decl_incomplete_type); 4212 } 4213 } 4214 4215 // Record the tentative definition; we're done. 4216 if (!Var->isInvalidDecl()) 4217 TentativeDefinitions.push_back(Var); 4218 return; 4219 } 4220 4221 // Provide a specific diagnostic for uninitialized variable 4222 // definitions with incomplete array type. 4223 if (Type->isIncompleteArrayType()) { 4224 Diag(Var->getLocation(), 4225 diag::err_typecheck_incomplete_array_needs_initializer); 4226 Var->setInvalidDecl(); 4227 return; 4228 } 4229 4230 // Provide a specific diagnostic for uninitialized variable 4231 // definitions with reference type. 4232 if (Type->isReferenceType()) { 4233 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 4234 << Var->getDeclName() 4235 << SourceRange(Var->getLocation(), Var->getLocation()); 4236 Var->setInvalidDecl(); 4237 return; 4238 } 4239 4240 // Do not attempt to type-check the default initializer for a 4241 // variable with dependent type. 4242 if (Type->isDependentType()) 4243 return; 4244 4245 if (Var->isInvalidDecl()) 4246 return; 4247 4248 if (RequireCompleteType(Var->getLocation(), 4249 Context.getBaseElementType(Type), 4250 diag::err_typecheck_decl_incomplete_type)) { 4251 Var->setInvalidDecl(); 4252 return; 4253 } 4254 4255 // The variable can not have an abstract class type. 4256 if (RequireNonAbstractType(Var->getLocation(), Type, 4257 diag::err_abstract_type_in_decl, 4258 AbstractVariableType)) { 4259 Var->setInvalidDecl(); 4260 return; 4261 } 4262 4263 const RecordType *Record 4264 = Context.getBaseElementType(Type)->getAs<RecordType>(); 4265 if (Record && getLangOptions().CPlusPlus && !getLangOptions().CPlusPlus0x && 4266 cast<CXXRecordDecl>(Record->getDecl())->isPOD()) { 4267 // C++03 [dcl.init]p9: 4268 // If no initializer is specified for an object, and the 4269 // object is of (possibly cv-qualified) non-POD class type (or 4270 // array thereof), the object shall be default-initialized; if 4271 // the object is of const-qualified type, the underlying class 4272 // type shall have a user-declared default 4273 // constructor. Otherwise, if no initializer is specified for 4274 // a non- static object, the object and its subobjects, if 4275 // any, have an indeterminate initial value); if the object 4276 // or any of its subobjects are of const-qualified type, the 4277 // program is ill-formed. 4278 // FIXME: DPG thinks it is very fishy that C++0x disables this. 4279 } else { 4280 InitializedEntity Entity = InitializedEntity::InitializeVariable(Var); 4281 InitializationKind Kind 4282 = InitializationKind::CreateDefault(Var->getLocation()); 4283 4284 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 4285 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 4286 MultiExprArg(*this, 0, 0)); 4287 if (Init.isInvalid()) 4288 Var->setInvalidDecl(); 4289 else if (Init.get()) 4290 Var->setInit(MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 4291 } 4292 4293 if (!Var->isInvalidDecl() && getLangOptions().CPlusPlus && Record) 4294 FinalizeVarWithDestructor(Var, Record); 4295 } 4296} 4297 4298Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 4299 DeclPtrTy *Group, 4300 unsigned NumDecls) { 4301 llvm::SmallVector<Decl*, 8> Decls; 4302 4303 if (DS.isTypeSpecOwned()) 4304 Decls.push_back((Decl*)DS.getTypeRep()); 4305 4306 for (unsigned i = 0; i != NumDecls; ++i) 4307 if (Decl *D = Group[i].getAs<Decl>()) 4308 Decls.push_back(D); 4309 4310 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 4311 Decls.data(), Decls.size())); 4312} 4313 4314 4315/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 4316/// to introduce parameters into function prototype scope. 4317Sema::DeclPtrTy 4318Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 4319 const DeclSpec &DS = D.getDeclSpec(); 4320 4321 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 4322 VarDecl::StorageClass StorageClass = VarDecl::None; 4323 VarDecl::StorageClass StorageClassAsWritten = VarDecl::None; 4324 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 4325 StorageClass = VarDecl::Register; 4326 StorageClassAsWritten = VarDecl::Register; 4327 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 4328 Diag(DS.getStorageClassSpecLoc(), 4329 diag::err_invalid_storage_class_in_func_decl); 4330 D.getMutableDeclSpec().ClearStorageClassSpecs(); 4331 } 4332 4333 if (D.getDeclSpec().isThreadSpecified()) 4334 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4335 4336 DiagnoseFunctionSpecifiers(D); 4337 4338 // Check that there are no default arguments inside the type of this 4339 // parameter (C++ only). 4340 if (getLangOptions().CPlusPlus) 4341 CheckExtraCXXDefaultArguments(D); 4342 4343 TagDecl *OwnedDecl = 0; 4344 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S, &OwnedDecl); 4345 QualType parmDeclType = TInfo->getType(); 4346 4347 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 4348 // C++ [dcl.fct]p6: 4349 // Types shall not be defined in return or parameter types. 4350 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 4351 << Context.getTypeDeclType(OwnedDecl); 4352 } 4353 4354 // Check for redeclaration of parameters, e.g. int foo(int x, int x); 4355 IdentifierInfo *II = D.getIdentifier(); 4356 if (II) { 4357 LookupResult R(*this, II, D.getIdentifierLoc(), LookupOrdinaryName, 4358 ForRedeclaration); 4359 LookupName(R, S); 4360 if (R.isSingleResult()) { 4361 NamedDecl *PrevDecl = R.getFoundDecl(); 4362 if (PrevDecl->isTemplateParameter()) { 4363 // Maybe we will complain about the shadowed template parameter. 4364 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4365 // Just pretend that we didn't see the previous declaration. 4366 PrevDecl = 0; 4367 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 4368 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 4369 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4370 4371 // Recover by removing the name 4372 II = 0; 4373 D.SetIdentifier(0, D.getIdentifierLoc()); 4374 D.setInvalidType(true); 4375 } 4376 } 4377 } 4378 4379 // Temporarily put parameter variables in the translation unit, not 4380 // the enclosing context. This prevents them from accidentally 4381 // looking like class members in C++. 4382 ParmVarDecl *New = CheckParameter(Context.getTranslationUnitDecl(), 4383 TInfo, parmDeclType, II, 4384 D.getIdentifierLoc(), 4385 StorageClass, StorageClassAsWritten); 4386 4387 if (D.isInvalidType()) 4388 New->setInvalidDecl(); 4389 4390 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 4391 if (D.getCXXScopeSpec().isSet()) { 4392 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 4393 << D.getCXXScopeSpec().getRange(); 4394 New->setInvalidDecl(); 4395 } 4396 4397 // Add the parameter declaration into this scope. 4398 S->AddDecl(DeclPtrTy::make(New)); 4399 if (II) 4400 IdResolver.AddDecl(New); 4401 4402 ProcessDeclAttributes(S, New, D); 4403 4404 if (New->hasAttr<BlocksAttr>()) { 4405 Diag(New->getLocation(), diag::err_block_on_nonlocal); 4406 } 4407 return DeclPtrTy::make(New); 4408} 4409 4410/// \brief Synthesizes a variable for a parameter arising from a 4411/// typedef. 4412ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC, 4413 SourceLocation Loc, 4414 QualType T) { 4415 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, Loc, 0, 4416 T, Context.getTrivialTypeSourceInfo(T, Loc), 4417 VarDecl::None, VarDecl::None, 0); 4418 Param->setImplicit(); 4419 return Param; 4420} 4421 4422ParmVarDecl *Sema::CheckParameter(DeclContext *DC, 4423 TypeSourceInfo *TSInfo, QualType T, 4424 IdentifierInfo *Name, 4425 SourceLocation NameLoc, 4426 VarDecl::StorageClass StorageClass, 4427 VarDecl::StorageClass StorageClassAsWritten) { 4428 ParmVarDecl *New = ParmVarDecl::Create(Context, DC, NameLoc, Name, 4429 adjustParameterType(T), TSInfo, 4430 StorageClass, StorageClassAsWritten, 4431 0); 4432 4433 // Parameters can not be abstract class types. 4434 // For record types, this is done by the AbstractClassUsageDiagnoser once 4435 // the class has been completely parsed. 4436 if (!CurContext->isRecord() && 4437 RequireNonAbstractType(NameLoc, T, diag::err_abstract_type_in_decl, 4438 AbstractParamType)) 4439 New->setInvalidDecl(); 4440 4441 // Parameter declarators cannot be interface types. All ObjC objects are 4442 // passed by reference. 4443 if (T->isObjCObjectType()) { 4444 Diag(NameLoc, 4445 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 4446 New->setInvalidDecl(); 4447 } 4448 4449 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 4450 // duration shall not be qualified by an address-space qualifier." 4451 // Since all parameters have automatic store duration, they can not have 4452 // an address space. 4453 if (T.getAddressSpace() != 0) { 4454 Diag(NameLoc, diag::err_arg_with_address_space); 4455 New->setInvalidDecl(); 4456 } 4457 4458 return New; 4459} 4460 4461void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4462 SourceLocation LocAfterDecls) { 4463 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4464 "Not a function declarator!"); 4465 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4466 4467 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4468 // for a K&R function. 4469 if (!FTI.hasPrototype) { 4470 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4471 --i; 4472 if (FTI.ArgInfo[i].Param == 0) { 4473 llvm::SmallString<256> Code; 4474 llvm::raw_svector_ostream(Code) << " int " 4475 << FTI.ArgInfo[i].Ident->getName() 4476 << ";\n"; 4477 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4478 << FTI.ArgInfo[i].Ident 4479 << FixItHint::CreateInsertion(LocAfterDecls, Code.str()); 4480 4481 // Implicitly declare the argument as type 'int' for lack of a better 4482 // type. 4483 DeclSpec DS; 4484 const char* PrevSpec; // unused 4485 unsigned DiagID; // unused 4486 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4487 PrevSpec, DiagID); 4488 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4489 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4490 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4491 } 4492 } 4493 } 4494} 4495 4496Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4497 Declarator &D) { 4498 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4499 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4500 "Not a function declarator!"); 4501 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4502 4503 if (FTI.hasPrototype) { 4504 // FIXME: Diagnose arguments without names in C. 4505 } 4506 4507 Scope *ParentScope = FnBodyScope->getParent(); 4508 4509 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4510 MultiTemplateParamsArg(*this), 4511 /*IsFunctionDefinition=*/true); 4512 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4513} 4514 4515static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4516 // Don't warn about invalid declarations. 4517 if (FD->isInvalidDecl()) 4518 return false; 4519 4520 // Or declarations that aren't global. 4521 if (!FD->isGlobal()) 4522 return false; 4523 4524 // Don't warn about C++ member functions. 4525 if (isa<CXXMethodDecl>(FD)) 4526 return false; 4527 4528 // Don't warn about 'main'. 4529 if (FD->isMain()) 4530 return false; 4531 4532 // Don't warn about inline functions. 4533 if (FD->isInlineSpecified()) 4534 return false; 4535 4536 // Don't warn about function templates. 4537 if (FD->getDescribedFunctionTemplate()) 4538 return false; 4539 4540 // Don't warn about function template specializations. 4541 if (FD->isFunctionTemplateSpecialization()) 4542 return false; 4543 4544 bool MissingPrototype = true; 4545 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4546 Prev; Prev = Prev->getPreviousDeclaration()) { 4547 // Ignore any declarations that occur in function or method 4548 // scope, because they aren't visible from the header. 4549 if (Prev->getDeclContext()->isFunctionOrMethod()) 4550 continue; 4551 4552 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4553 break; 4554 } 4555 4556 return MissingPrototype; 4557} 4558 4559Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4560 // Clear the last template instantiation error context. 4561 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4562 4563 if (!D) 4564 return D; 4565 FunctionDecl *FD = 0; 4566 4567 if (FunctionTemplateDecl *FunTmpl 4568 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4569 FD = FunTmpl->getTemplatedDecl(); 4570 else 4571 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4572 4573 // Enter a new function scope 4574 PushFunctionScope(); 4575 4576 // See if this is a redefinition. 4577 // But don't complain if we're in GNU89 mode and the previous definition 4578 // was an extern inline function. 4579 const FunctionDecl *Definition; 4580 if (FD->hasBody(Definition) && 4581 !canRedefineFunction(Definition, getLangOptions())) { 4582 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4583 Diag(Definition->getLocation(), diag::note_previous_definition); 4584 } 4585 4586 // Builtin functions cannot be defined. 4587 if (unsigned BuiltinID = FD->getBuiltinID()) { 4588 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4589 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4590 FD->setInvalidDecl(); 4591 } 4592 } 4593 4594 // The return type of a function definition must be complete 4595 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4596 QualType ResultType = FD->getResultType(); 4597 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4598 !FD->isInvalidDecl() && 4599 RequireCompleteType(FD->getLocation(), ResultType, 4600 diag::err_func_def_incomplete_result)) 4601 FD->setInvalidDecl(); 4602 4603 // GNU warning -Wmissing-prototypes: 4604 // Warn if a global function is defined without a previous 4605 // prototype declaration. This warning is issued even if the 4606 // definition itself provides a prototype. The aim is to detect 4607 // global functions that fail to be declared in header files. 4608 if (ShouldWarnAboutMissingPrototype(FD)) 4609 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4610 4611 if (FnBodyScope) 4612 PushDeclContext(FnBodyScope, FD); 4613 4614 // Check the validity of our function parameters 4615 CheckParmsForFunctionDef(FD); 4616 4617 bool ShouldCheckShadow = 4618 Diags.getDiagnosticLevel(diag::warn_decl_shadow) != Diagnostic::Ignored; 4619 4620 // Introduce our parameters into the function scope 4621 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4622 ParmVarDecl *Param = FD->getParamDecl(p); 4623 Param->setOwningFunction(FD); 4624 4625 // If this has an identifier, add it to the scope stack. 4626 if (Param->getIdentifier() && FnBodyScope) { 4627 if (ShouldCheckShadow) 4628 CheckShadow(FnBodyScope, Param); 4629 4630 PushOnScopeChains(Param, FnBodyScope); 4631 } 4632 } 4633 4634 // Checking attributes of current function definition 4635 // dllimport attribute. 4636 if (FD->getAttr<DLLImportAttr>() && 4637 (!FD->getAttr<DLLExportAttr>())) { 4638 // dllimport attribute cannot be applied to definition. 4639 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4640 Diag(FD->getLocation(), 4641 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4642 << "dllimport"; 4643 FD->setInvalidDecl(); 4644 return DeclPtrTy::make(FD); 4645 } 4646 4647 // Visual C++ appears to not think this is an issue, so only issue 4648 // a warning when Microsoft extensions are disabled. 4649 if (!LangOpts.Microsoft) { 4650 // If a symbol previously declared dllimport is later defined, the 4651 // attribute is ignored in subsequent references, and a warning is 4652 // emitted. 4653 Diag(FD->getLocation(), 4654 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4655 << FD->getNameAsCString() << "dllimport"; 4656 } 4657 } 4658 return DeclPtrTy::make(FD); 4659} 4660 4661/// \brief Given the set of return statements within a function body, 4662/// compute the variables that are subject to the named return value 4663/// optimization. 4664/// 4665/// Each of the variables that is subject to the named return value 4666/// optimization will be marked as NRVO variables in the AST, and any 4667/// return statement that has a marked NRVO variable as its NRVO candidate can 4668/// use the named return value optimization. 4669/// 4670/// This function applies a very simplistic algorithm for NRVO: if every return 4671/// statement in the function has the same NRVO candidate, that candidate is 4672/// the NRVO variable. 4673/// 4674/// FIXME: Employ a smarter algorithm that accounts for multiple return 4675/// statements and the lifetimes of the NRVO candidates. We should be able to 4676/// find a maximal set of NRVO variables. 4677static void ComputeNRVO(Stmt *Body, ReturnStmt **Returns, unsigned NumReturns) { 4678 const VarDecl *NRVOCandidate = 0; 4679 for (unsigned I = 0; I != NumReturns; ++I) { 4680 if (!Returns[I]->getNRVOCandidate()) 4681 return; 4682 4683 if (!NRVOCandidate) 4684 NRVOCandidate = Returns[I]->getNRVOCandidate(); 4685 else if (NRVOCandidate != Returns[I]->getNRVOCandidate()) 4686 return; 4687 } 4688 4689 if (NRVOCandidate) 4690 const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true); 4691} 4692 4693Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4694 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4695} 4696 4697Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4698 bool IsInstantiation) { 4699 Decl *dcl = D.getAs<Decl>(); 4700 Stmt *Body = BodyArg.takeAs<Stmt>(); 4701 4702 FunctionDecl *FD = 0; 4703 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4704 if (FunTmpl) 4705 FD = FunTmpl->getTemplatedDecl(); 4706 else 4707 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4708 4709 sema::AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy(); 4710 4711 if (FD) { 4712 FD->setBody(Body); 4713 if (FD->isMain()) { 4714 // C and C++ allow for main to automagically return 0. 4715 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4716 FD->setHasImplicitReturnZero(true); 4717 WP.disableCheckFallThrough(); 4718 } 4719 4720 if (!FD->isInvalidDecl()) { 4721 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4722 4723 // If this is a constructor, we need a vtable. 4724 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(FD)) 4725 MarkVTableUsed(FD->getLocation(), Constructor->getParent()); 4726 4727 ComputeNRVO(Body, FunctionScopes.back()->Returns.data(), 4728 FunctionScopes.back()->Returns.size()); 4729 } 4730 4731 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4732 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4733 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4734 MD->setBody(Body); 4735 MD->setEndLoc(Body->getLocEnd()); 4736 if (!MD->isInvalidDecl()) 4737 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4738 } else { 4739 return DeclPtrTy(); 4740 } 4741 4742 // Verify and clean out per-function state. 4743 4744 // Check goto/label use. 4745 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4746 I = getLabelMap().begin(), E = getLabelMap().end(); I != E; ++I) { 4747 LabelStmt *L = I->second; 4748 4749 // Verify that we have no forward references left. If so, there was a goto 4750 // or address of a label taken, but no definition of it. Label fwd 4751 // definitions are indicated with a null substmt. 4752 if (L->getSubStmt() != 0) 4753 continue; 4754 4755 // Emit error. 4756 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4757 4758 // At this point, we have gotos that use the bogus label. Stitch it into 4759 // the function body so that they aren't leaked and that the AST is well 4760 // formed. 4761 if (Body == 0) { 4762 // The whole function wasn't parsed correctly. 4763 continue; 4764 } 4765 4766 // Otherwise, the body is valid: we want to stitch the label decl into the 4767 // function somewhere so that it is properly owned and so that the goto 4768 // has a valid target. Do this by creating a new compound stmt with the 4769 // label in it. 4770 4771 // Give the label a sub-statement. 4772 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4773 4774 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4775 cast<CXXTryStmt>(Body)->getTryBlock() : 4776 cast<CompoundStmt>(Body); 4777 llvm::SmallVector<Stmt*, 64> Elements(Compound->body_begin(), 4778 Compound->body_end()); 4779 Elements.push_back(L); 4780 Compound->setStmts(Context, Elements.data(), Elements.size()); 4781 } 4782 4783 if (Body) { 4784 // C++ constructors that have function-try-blocks can't have return 4785 // statements in the handlers of that block. (C++ [except.handle]p14) 4786 // Verify this. 4787 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4788 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4789 4790 // Verify that that gotos and switch cases don't jump into scopes illegally. 4791 // Verify that that gotos and switch cases don't jump into scopes illegally. 4792 if (FunctionNeedsScopeChecking() && 4793 !dcl->isInvalidDecl() && 4794 !hasAnyErrorsInThisFunction()) 4795 DiagnoseInvalidJumps(Body); 4796 4797 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4798 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(), 4799 Destructor->getParent()); 4800 4801 // If any errors have occurred, clear out any temporaries that may have 4802 // been leftover. This ensures that these temporaries won't be picked up for 4803 // deletion in some later function. 4804 if (PP.getDiagnostics().hasErrorOccurred()) 4805 ExprTemporaries.clear(); 4806 else if (!isa<FunctionTemplateDecl>(dcl)) { 4807 // Since the body is valid, issue any analysis-based warnings that are 4808 // enabled. 4809 QualType ResultType; 4810 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(dcl)) { 4811 ResultType = FD->getResultType(); 4812 } 4813 else { 4814 ObjCMethodDecl *MD = cast<ObjCMethodDecl>(dcl); 4815 ResultType = MD->getResultType(); 4816 } 4817 AnalysisWarnings.IssueWarnings(WP, dcl); 4818 } 4819 4820 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4821 } 4822 4823 if (!IsInstantiation) 4824 PopDeclContext(); 4825 4826 PopFunctionOrBlockScope(); 4827 4828 // If any errors have occurred, clear out any temporaries that may have 4829 // been leftover. This ensures that these temporaries won't be picked up for 4830 // deletion in some later function. 4831 if (getDiagnostics().hasErrorOccurred()) 4832 ExprTemporaries.clear(); 4833 4834 return D; 4835} 4836 4837/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4838/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4839NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4840 IdentifierInfo &II, Scope *S) { 4841 // Before we produce a declaration for an implicitly defined 4842 // function, see whether there was a locally-scoped declaration of 4843 // this name as a function or variable. If so, use that 4844 // (non-visible) declaration, and complain about it. 4845 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4846 = LocallyScopedExternalDecls.find(&II); 4847 if (Pos != LocallyScopedExternalDecls.end()) { 4848 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4849 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4850 return Pos->second; 4851 } 4852 4853 // Extension in C99. Legal in C90, but warn about it. 4854 if (II.getName().startswith("__builtin_")) 4855 Diag(Loc, diag::warn_builtin_unknown) << &II; 4856 else if (getLangOptions().C99) 4857 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4858 else 4859 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4860 4861 // Set a Declarator for the implicit definition: int foo(); 4862 const char *Dummy; 4863 DeclSpec DS; 4864 unsigned DiagID; 4865 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4866 Error = Error; // Silence warning. 4867 assert(!Error && "Error setting up implicit decl!"); 4868 Declarator D(DS, Declarator::BlockContext); 4869 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4870 0, 0, false, SourceLocation(), 4871 false, 0,0,0, Loc, Loc, D), 4872 SourceLocation()); 4873 D.SetIdentifier(&II, Loc); 4874 4875 // Insert this function into translation-unit scope. 4876 4877 DeclContext *PrevDC = CurContext; 4878 CurContext = Context.getTranslationUnitDecl(); 4879 4880 FunctionDecl *FD = 4881 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4882 FD->setImplicit(); 4883 4884 CurContext = PrevDC; 4885 4886 AddKnownFunctionAttributes(FD); 4887 4888 return FD; 4889} 4890 4891/// \brief Adds any function attributes that we know a priori based on 4892/// the declaration of this function. 4893/// 4894/// These attributes can apply both to implicitly-declared builtins 4895/// (like __builtin___printf_chk) or to library-declared functions 4896/// like NSLog or printf. 4897void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4898 if (FD->isInvalidDecl()) 4899 return; 4900 4901 // If this is a built-in function, map its builtin attributes to 4902 // actual attributes. 4903 if (unsigned BuiltinID = FD->getBuiltinID()) { 4904 // Handle printf-formatting attributes. 4905 unsigned FormatIdx; 4906 bool HasVAListArg; 4907 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4908 if (!FD->getAttr<FormatAttr>()) 4909 FD->addAttr(::new (Context) FormatAttr(Context, "printf", FormatIdx+1, 4910 HasVAListArg ? 0 : FormatIdx+2)); 4911 } 4912 if (Context.BuiltinInfo.isScanfLike(BuiltinID, FormatIdx, 4913 HasVAListArg)) { 4914 if (!FD->getAttr<FormatAttr>()) 4915 FD->addAttr(::new (Context) FormatAttr(Context, "scanf", FormatIdx+1, 4916 HasVAListArg ? 0 : FormatIdx+2)); 4917 } 4918 4919 // Mark const if we don't care about errno and that is the only 4920 // thing preventing the function from being const. This allows 4921 // IRgen to use LLVM intrinsics for such functions. 4922 if (!getLangOptions().MathErrno && 4923 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4924 if (!FD->getAttr<ConstAttr>()) 4925 FD->addAttr(::new (Context) ConstAttr()); 4926 } 4927 4928 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4929 FD->setType(Context.getNoReturnType(FD->getType())); 4930 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4931 FD->addAttr(::new (Context) NoThrowAttr()); 4932 if (Context.BuiltinInfo.isConst(BuiltinID)) 4933 FD->addAttr(::new (Context) ConstAttr()); 4934 } 4935 4936 IdentifierInfo *Name = FD->getIdentifier(); 4937 if (!Name) 4938 return; 4939 if ((!getLangOptions().CPlusPlus && 4940 FD->getDeclContext()->isTranslationUnit()) || 4941 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4942 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4943 LinkageSpecDecl::lang_c)) { 4944 // Okay: this could be a libc/libm/Objective-C function we know 4945 // about. 4946 } else 4947 return; 4948 4949 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4950 // FIXME: NSLog and NSLogv should be target specific 4951 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4952 // FIXME: We known better than our headers. 4953 const_cast<FormatAttr *>(Format)->setType(Context, "printf"); 4954 } else 4955 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 1, 4956 Name->isStr("NSLogv") ? 0 : 2)); 4957 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4958 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4959 // target-specific builtins, perhaps? 4960 if (!FD->getAttr<FormatAttr>()) 4961 FD->addAttr(::new (Context) FormatAttr(Context, "printf", 2, 4962 Name->isStr("vasprintf") ? 0 : 3)); 4963 } 4964} 4965 4966TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4967 TypeSourceInfo *TInfo) { 4968 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4969 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4970 4971 if (!TInfo) { 4972 assert(D.isInvalidType() && "no declarator info for valid type"); 4973 TInfo = Context.getTrivialTypeSourceInfo(T); 4974 } 4975 4976 // Scope manipulation handled by caller. 4977 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4978 D.getIdentifierLoc(), 4979 D.getIdentifier(), 4980 TInfo); 4981 4982 if (const TagType *TT = T->getAs<TagType>()) { 4983 TagDecl *TD = TT->getDecl(); 4984 4985 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4986 // keep track of the TypedefDecl. 4987 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4988 TD->setTypedefForAnonDecl(NewTD); 4989 } 4990 4991 if (D.isInvalidType()) 4992 NewTD->setInvalidDecl(); 4993 return NewTD; 4994} 4995 4996 4997/// \brief Determine whether a tag with a given kind is acceptable 4998/// as a redeclaration of the given tag declaration. 4999/// 5000/// \returns true if the new tag kind is acceptable, false otherwise. 5001bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 5002 TagTypeKind NewTag, 5003 SourceLocation NewTagLoc, 5004 const IdentifierInfo &Name) { 5005 // C++ [dcl.type.elab]p3: 5006 // The class-key or enum keyword present in the 5007 // elaborated-type-specifier shall agree in kind with the 5008 // declaration to which the name in the elaborated-type-specifier 5009 // refers. This rule also applies to the form of 5010 // elaborated-type-specifier that declares a class-name or 5011 // friend class since it can be construed as referring to the 5012 // definition of the class. Thus, in any 5013 // elaborated-type-specifier, the enum keyword shall be used to 5014 // refer to an enumeration (7.2), the union class-key shall be 5015 // used to refer to a union (clause 9), and either the class or 5016 // struct class-key shall be used to refer to a class (clause 9) 5017 // declared using the class or struct class-key. 5018 TagTypeKind OldTag = Previous->getTagKind(); 5019 if (OldTag == NewTag) 5020 return true; 5021 5022 if ((OldTag == TTK_Struct || OldTag == TTK_Class) && 5023 (NewTag == TTK_Struct || NewTag == TTK_Class)) { 5024 // Warn about the struct/class tag mismatch. 5025 bool isTemplate = false; 5026 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 5027 isTemplate = Record->getDescribedClassTemplate(); 5028 5029 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 5030 << (NewTag == TTK_Class) 5031 << isTemplate << &Name 5032 << FixItHint::CreateReplacement(SourceRange(NewTagLoc), 5033 OldTag == TTK_Class? "class" : "struct"); 5034 Diag(Previous->getLocation(), diag::note_previous_use); 5035 return true; 5036 } 5037 return false; 5038} 5039 5040/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 5041/// former case, Name will be non-null. In the later case, Name will be null. 5042/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 5043/// reference/declaration/definition of a tag. 5044Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 5045 SourceLocation KWLoc, CXXScopeSpec &SS, 5046 IdentifierInfo *Name, SourceLocation NameLoc, 5047 AttributeList *Attr, AccessSpecifier AS, 5048 MultiTemplateParamsArg TemplateParameterLists, 5049 bool &OwnedDecl, bool &IsDependent) { 5050 // If this is not a definition, it must have a name. 5051 assert((Name != 0 || TUK == TUK_Definition) && 5052 "Nameless record must be a definition!"); 5053 5054 OwnedDecl = false; 5055 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec); 5056 5057 // FIXME: Check explicit specializations more carefully. 5058 bool isExplicitSpecialization = false; 5059 unsigned NumMatchedTemplateParamLists = TemplateParameterLists.size(); 5060 bool Invalid = false; 5061 if (TUK != TUK_Reference) { 5062 if (TemplateParameterList *TemplateParams 5063 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 5064 (TemplateParameterList**)TemplateParameterLists.get(), 5065 TemplateParameterLists.size(), 5066 TUK == TUK_Friend, 5067 isExplicitSpecialization, 5068 Invalid)) { 5069 // All but one template parameter lists have been matching. 5070 --NumMatchedTemplateParamLists; 5071 5072 if (TemplateParams->size() > 0) { 5073 // This is a declaration or definition of a class template (which may 5074 // be a member of another template). 5075 if (Invalid) 5076 return DeclPtrTy(); 5077 5078 OwnedDecl = false; 5079 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 5080 SS, Name, NameLoc, Attr, 5081 TemplateParams, 5082 AS); 5083 TemplateParameterLists.release(); 5084 return Result.get(); 5085 } else { 5086 // The "template<>" header is extraneous. 5087 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 5088 << TypeWithKeyword::getTagTypeKindName(Kind) << Name; 5089 isExplicitSpecialization = true; 5090 } 5091 } 5092 } 5093 5094 DeclContext *SearchDC = CurContext; 5095 DeclContext *DC = CurContext; 5096 bool isStdBadAlloc = false; 5097 5098 RedeclarationKind Redecl = ForRedeclaration; 5099 if (TUK == TUK_Friend || TUK == TUK_Reference) 5100 Redecl = NotForRedeclaration; 5101 5102 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 5103 5104 if (Name && SS.isNotEmpty()) { 5105 // We have a nested-name tag ('struct foo::bar'). 5106 5107 // Check for invalid 'foo::'. 5108 if (SS.isInvalid()) { 5109 Name = 0; 5110 goto CreateNewDecl; 5111 } 5112 5113 // If this is a friend or a reference to a class in a dependent 5114 // context, don't try to make a decl for it. 5115 if (TUK == TUK_Friend || TUK == TUK_Reference) { 5116 DC = computeDeclContext(SS, false); 5117 if (!DC) { 5118 IsDependent = true; 5119 return DeclPtrTy(); 5120 } 5121 } else { 5122 DC = computeDeclContext(SS, true); 5123 if (!DC) { 5124 Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec) 5125 << SS.getRange(); 5126 return DeclPtrTy(); 5127 } 5128 } 5129 5130 if (RequireCompleteDeclContext(SS, DC)) 5131 return DeclPtrTy::make((Decl *)0); 5132 5133 SearchDC = DC; 5134 // Look-up name inside 'foo::'. 5135 LookupQualifiedName(Previous, DC); 5136 5137 if (Previous.isAmbiguous()) 5138 return DeclPtrTy(); 5139 5140 if (Previous.empty()) { 5141 // Name lookup did not find anything. However, if the 5142 // nested-name-specifier refers to the current instantiation, 5143 // and that current instantiation has any dependent base 5144 // classes, we might find something at instantiation time: treat 5145 // this as a dependent elaborated-type-specifier. 5146 if (Previous.wasNotFoundInCurrentInstantiation()) { 5147 IsDependent = true; 5148 return DeclPtrTy(); 5149 } 5150 5151 // A tag 'foo::bar' must already exist. 5152 Diag(NameLoc, diag::err_not_tag_in_scope) 5153 << Kind << Name << DC << SS.getRange(); 5154 Name = 0; 5155 Invalid = true; 5156 goto CreateNewDecl; 5157 } 5158 } else if (Name) { 5159 // If this is a named struct, check to see if there was a previous forward 5160 // declaration or definition. 5161 // FIXME: We're looking into outer scopes here, even when we 5162 // shouldn't be. Doing so can result in ambiguities that we 5163 // shouldn't be diagnosing. 5164 LookupName(Previous, S); 5165 5166 // Note: there used to be some attempt at recovery here. 5167 if (Previous.isAmbiguous()) 5168 return DeclPtrTy(); 5169 5170 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 5171 // FIXME: This makes sure that we ignore the contexts associated 5172 // with C structs, unions, and enums when looking for a matching 5173 // tag declaration or definition. See the similar lookup tweak 5174 // in Sema::LookupName; is there a better way to deal with this? 5175 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 5176 SearchDC = SearchDC->getParent(); 5177 } 5178 } 5179 5180 if (Previous.isSingleResult() && 5181 Previous.getFoundDecl()->isTemplateParameter()) { 5182 // Maybe we will complain about the shadowed template parameter. 5183 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 5184 // Just pretend that we didn't see the previous declaration. 5185 Previous.clear(); 5186 } 5187 5188 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 5189 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 5190 // This is a declaration of or a reference to "std::bad_alloc". 5191 isStdBadAlloc = true; 5192 5193 if (Previous.empty() && StdBadAlloc) { 5194 // std::bad_alloc has been implicitly declared (but made invisible to 5195 // name lookup). Fill in this implicit declaration as the previous 5196 // declaration, so that the declarations get chained appropriately. 5197 Previous.addDecl(StdBadAlloc); 5198 } 5199 } 5200 5201 // If we didn't find a previous declaration, and this is a reference 5202 // (or friend reference), move to the correct scope. In C++, we 5203 // also need to do a redeclaration lookup there, just in case 5204 // there's a shadow friend decl. 5205 if (Name && Previous.empty() && 5206 (TUK == TUK_Reference || TUK == TUK_Friend)) { 5207 if (Invalid) goto CreateNewDecl; 5208 assert(SS.isEmpty()); 5209 5210 if (TUK == TUK_Reference) { 5211 // C++ [basic.scope.pdecl]p5: 5212 // -- for an elaborated-type-specifier of the form 5213 // 5214 // class-key identifier 5215 // 5216 // if the elaborated-type-specifier is used in the 5217 // decl-specifier-seq or parameter-declaration-clause of a 5218 // function defined in namespace scope, the identifier is 5219 // declared as a class-name in the namespace that contains 5220 // the declaration; otherwise, except as a friend 5221 // declaration, the identifier is declared in the smallest 5222 // non-class, non-function-prototype scope that contains the 5223 // declaration. 5224 // 5225 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 5226 // C structs and unions. 5227 // 5228 // It is an error in C++ to declare (rather than define) an enum 5229 // type, including via an elaborated type specifier. We'll 5230 // diagnose that later; for now, declare the enum in the same 5231 // scope as we would have picked for any other tag type. 5232 // 5233 // GNU C also supports this behavior as part of its incomplete 5234 // enum types extension, while GNU C++ does not. 5235 // 5236 // Find the context where we'll be declaring the tag. 5237 // FIXME: We would like to maintain the current DeclContext as the 5238 // lexical context, 5239 while (SearchDC->isRecord()) 5240 SearchDC = SearchDC->getParent(); 5241 5242 // Find the scope where we'll be declaring the tag. 5243 while (S->isClassScope() || 5244 (getLangOptions().CPlusPlus && 5245 S->isFunctionPrototypeScope()) || 5246 ((S->getFlags() & Scope::DeclScope) == 0) || 5247 (S->getEntity() && 5248 ((DeclContext *)S->getEntity())->isTransparentContext())) 5249 S = S->getParent(); 5250 } else { 5251 assert(TUK == TUK_Friend); 5252 // C++ [namespace.memdef]p3: 5253 // If a friend declaration in a non-local class first declares a 5254 // class or function, the friend class or function is a member of 5255 // the innermost enclosing namespace. 5256 SearchDC = SearchDC->getEnclosingNamespaceContext(); 5257 } 5258 5259 // In C++, we need to do a redeclaration lookup to properly 5260 // diagnose some problems. 5261 if (getLangOptions().CPlusPlus) { 5262 Previous.setRedeclarationKind(ForRedeclaration); 5263 LookupQualifiedName(Previous, SearchDC); 5264 } 5265 } 5266 5267 if (!Previous.empty()) { 5268 NamedDecl *PrevDecl = (*Previous.begin())->getUnderlyingDecl(); 5269 5270 // It's okay to have a tag decl in the same scope as a typedef 5271 // which hides a tag decl in the same scope. Finding this 5272 // insanity with a redeclaration lookup can only actually happen 5273 // in C++. 5274 // 5275 // This is also okay for elaborated-type-specifiers, which is 5276 // technically forbidden by the current standard but which is 5277 // okay according to the likely resolution of an open issue; 5278 // see http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#407 5279 if (getLangOptions().CPlusPlus) { 5280 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(PrevDecl)) { 5281 if (const TagType *TT = TD->getUnderlyingType()->getAs<TagType>()) { 5282 TagDecl *Tag = TT->getDecl(); 5283 if (Tag->getDeclName() == Name && 5284 Tag->getDeclContext()->getLookupContext() 5285 ->Equals(TD->getDeclContext()->getLookupContext())) { 5286 PrevDecl = Tag; 5287 Previous.clear(); 5288 Previous.addDecl(Tag); 5289 } 5290 } 5291 } 5292 } 5293 5294 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 5295 // If this is a use of a previous tag, or if the tag is already declared 5296 // in the same scope (so that the definition/declaration completes or 5297 // rementions the tag), reuse the decl. 5298 if (TUK == TUK_Reference || TUK == TUK_Friend || 5299 isDeclInScope(PrevDecl, SearchDC, S)) { 5300 // Make sure that this wasn't declared as an enum and now used as a 5301 // struct or something similar. 5302 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 5303 bool SafeToContinue 5304 = (PrevTagDecl->getTagKind() != TTK_Enum && 5305 Kind != TTK_Enum); 5306 if (SafeToContinue) 5307 Diag(KWLoc, diag::err_use_with_wrong_tag) 5308 << Name 5309 << FixItHint::CreateReplacement(SourceRange(KWLoc), 5310 PrevTagDecl->getKindName()); 5311 else 5312 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 5313 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 5314 5315 if (SafeToContinue) 5316 Kind = PrevTagDecl->getTagKind(); 5317 else { 5318 // Recover by making this an anonymous redefinition. 5319 Name = 0; 5320 Previous.clear(); 5321 Invalid = true; 5322 } 5323 } 5324 5325 if (!Invalid) { 5326 // If this is a use, just return the declaration we found. 5327 5328 // FIXME: In the future, return a variant or some other clue 5329 // for the consumer of this Decl to know it doesn't own it. 5330 // For our current ASTs this shouldn't be a problem, but will 5331 // need to be changed with DeclGroups. 5332 if ((TUK == TUK_Reference && !PrevTagDecl->getFriendObjectKind()) || 5333 TUK == TUK_Friend) 5334 return DeclPtrTy::make(PrevTagDecl); 5335 5336 // Diagnose attempts to redefine a tag. 5337 if (TUK == TUK_Definition) { 5338 if (TagDecl *Def = PrevTagDecl->getDefinition()) { 5339 // If we're defining a specialization and the previous definition 5340 // is from an implicit instantiation, don't emit an error 5341 // here; we'll catch this in the general case below. 5342 if (!isExplicitSpecialization || 5343 !isa<CXXRecordDecl>(Def) || 5344 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 5345 == TSK_ExplicitSpecialization) { 5346 Diag(NameLoc, diag::err_redefinition) << Name; 5347 Diag(Def->getLocation(), diag::note_previous_definition); 5348 // If this is a redefinition, recover by making this 5349 // struct be anonymous, which will make any later 5350 // references get the previous definition. 5351 Name = 0; 5352 Previous.clear(); 5353 Invalid = true; 5354 } 5355 } else { 5356 // If the type is currently being defined, complain 5357 // about a nested redefinition. 5358 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 5359 if (Tag->isBeingDefined()) { 5360 Diag(NameLoc, diag::err_nested_redefinition) << Name; 5361 Diag(PrevTagDecl->getLocation(), 5362 diag::note_previous_definition); 5363 Name = 0; 5364 Previous.clear(); 5365 Invalid = true; 5366 } 5367 } 5368 5369 // Okay, this is definition of a previously declared or referenced 5370 // tag PrevDecl. We're going to create a new Decl for it. 5371 } 5372 } 5373 // If we get here we have (another) forward declaration or we 5374 // have a definition. Just create a new decl. 5375 5376 } else { 5377 // If we get here, this is a definition of a new tag type in a nested 5378 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 5379 // new decl/type. We set PrevDecl to NULL so that the entities 5380 // have distinct types. 5381 Previous.clear(); 5382 } 5383 // If we get here, we're going to create a new Decl. If PrevDecl 5384 // is non-NULL, it's a definition of the tag declared by 5385 // PrevDecl. If it's NULL, we have a new definition. 5386 5387 5388 // Otherwise, PrevDecl is not a tag, but was found with tag 5389 // lookup. This is only actually possible in C++, where a few 5390 // things like templates still live in the tag namespace. 5391 } else { 5392 assert(getLangOptions().CPlusPlus); 5393 5394 // Use a better diagnostic if an elaborated-type-specifier 5395 // found the wrong kind of type on the first 5396 // (non-redeclaration) lookup. 5397 if ((TUK == TUK_Reference || TUK == TUK_Friend) && 5398 !Previous.isForRedeclaration()) { 5399 unsigned Kind = 0; 5400 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5401 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5402 Diag(NameLoc, diag::err_tag_reference_non_tag) << Kind; 5403 Diag(PrevDecl->getLocation(), diag::note_declared_at); 5404 Invalid = true; 5405 5406 // Otherwise, only diagnose if the declaration is in scope. 5407 } else if (!isDeclInScope(PrevDecl, SearchDC, S)) { 5408 // do nothing 5409 5410 // Diagnose implicit declarations introduced by elaborated types. 5411 } else if (TUK == TUK_Reference || TUK == TUK_Friend) { 5412 unsigned Kind = 0; 5413 if (isa<TypedefDecl>(PrevDecl)) Kind = 1; 5414 else if (isa<ClassTemplateDecl>(PrevDecl)) Kind = 2; 5415 Diag(NameLoc, diag::err_tag_reference_conflict) << Kind; 5416 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5417 Invalid = true; 5418 5419 // Otherwise it's a declaration. Call out a particularly common 5420 // case here. 5421 } else if (isa<TypedefDecl>(PrevDecl)) { 5422 Diag(NameLoc, diag::err_tag_definition_of_typedef) 5423 << Name 5424 << cast<TypedefDecl>(PrevDecl)->getUnderlyingType(); 5425 Diag(PrevDecl->getLocation(), diag::note_previous_decl) << PrevDecl; 5426 Invalid = true; 5427 5428 // Otherwise, diagnose. 5429 } else { 5430 // The tag name clashes with something else in the target scope, 5431 // issue an error and recover by making this tag be anonymous. 5432 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 5433 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5434 Name = 0; 5435 Invalid = true; 5436 } 5437 5438 // The existing declaration isn't relevant to us; we're in a 5439 // new scope, so clear out the previous declaration. 5440 Previous.clear(); 5441 } 5442 } 5443 5444CreateNewDecl: 5445 5446 TagDecl *PrevDecl = 0; 5447 if (Previous.isSingleResult()) 5448 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 5449 5450 // If there is an identifier, use the location of the identifier as the 5451 // location of the decl, otherwise use the location of the struct/union 5452 // keyword. 5453 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 5454 5455 // Otherwise, create a new declaration. If there is a previous 5456 // declaration of the same entity, the two will be linked via 5457 // PrevDecl. 5458 TagDecl *New; 5459 5460 if (Kind == TTK_Enum) { 5461 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5462 // enum X { A, B, C } D; D should chain to X. 5463 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 5464 cast_or_null<EnumDecl>(PrevDecl)); 5465 // If this is an undefined enum, warn. 5466 if (TUK != TUK_Definition && !Invalid) { 5467 TagDecl *Def; 5468 if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) { 5469 Diag(Loc, diag::ext_forward_ref_enum_def) 5470 << New; 5471 Diag(Def->getLocation(), diag::note_previous_definition); 5472 } else { 5473 Diag(Loc, 5474 getLangOptions().CPlusPlus? diag::err_forward_ref_enum 5475 : diag::ext_forward_ref_enum); 5476 } 5477 } 5478 } else { 5479 // struct/union/class 5480 5481 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 5482 // struct X { int A; } D; D should chain to X. 5483 if (getLangOptions().CPlusPlus) { 5484 // FIXME: Look for a way to use RecordDecl for simple structs. 5485 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5486 cast_or_null<CXXRecordDecl>(PrevDecl)); 5487 5488 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 5489 StdBadAlloc = cast<CXXRecordDecl>(New); 5490 } else 5491 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 5492 cast_or_null<RecordDecl>(PrevDecl)); 5493 } 5494 5495 // Maybe add qualifier info. 5496 if (SS.isNotEmpty()) { 5497 if (SS.isSet()) { 5498 NestedNameSpecifier *NNS 5499 = static_cast<NestedNameSpecifier*>(SS.getScopeRep()); 5500 New->setQualifierInfo(NNS, SS.getRange()); 5501 if (NumMatchedTemplateParamLists > 0) { 5502 New->setTemplateParameterListsInfo(Context, 5503 NumMatchedTemplateParamLists, 5504 (TemplateParameterList**) TemplateParameterLists.release()); 5505 } 5506 } 5507 else 5508 Invalid = true; 5509 } 5510 5511 if (RecordDecl *RD = dyn_cast<RecordDecl>(New)) { 5512 // Add alignment attributes if necessary; these attributes are checked when 5513 // the ASTContext lays out the structure. 5514 // 5515 // It is important for implementing the correct semantics that this 5516 // happen here (in act on tag decl). The #pragma pack stack is 5517 // maintained as a result of parser callbacks which can occur at 5518 // many points during the parsing of a struct declaration (because 5519 // the #pragma tokens are effectively skipped over during the 5520 // parsing of the struct). 5521 AddAlignmentAttributesForRecord(RD); 5522 } 5523 5524 // If this is a specialization of a member class (of a class template), 5525 // check the specialization. 5526 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 5527 Invalid = true; 5528 5529 if (Invalid) 5530 New->setInvalidDecl(); 5531 5532 if (Attr) 5533 ProcessDeclAttributeList(S, New, Attr); 5534 5535 // If we're declaring or defining a tag in function prototype scope 5536 // in C, note that this type can only be used within the function. 5537 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 5538 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 5539 5540 // Set the lexical context. If the tag has a C++ scope specifier, the 5541 // lexical context will be different from the semantic context. 5542 New->setLexicalDeclContext(CurContext); 5543 5544 // Mark this as a friend decl if applicable. 5545 if (TUK == TUK_Friend) 5546 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 5547 5548 // Set the access specifier. 5549 if (!Invalid && SearchDC->isRecord()) 5550 SetMemberAccessSpecifier(New, PrevDecl, AS); 5551 5552 if (TUK == TUK_Definition) 5553 New->startDefinition(); 5554 5555 // If this has an identifier, add it to the scope stack. 5556 if (TUK == TUK_Friend) { 5557 // We might be replacing an existing declaration in the lookup tables; 5558 // if so, borrow its access specifier. 5559 if (PrevDecl) 5560 New->setAccess(PrevDecl->getAccess()); 5561 5562 DeclContext *DC = New->getDeclContext()->getLookupContext(); 5563 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 5564 if (Name) // can be null along some error paths 5565 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 5566 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 5567 } else if (Name) { 5568 S = getNonFieldDeclScope(S); 5569 PushOnScopeChains(New, S); 5570 } else { 5571 CurContext->addDecl(New); 5572 } 5573 5574 // If this is the C FILE type, notify the AST context. 5575 if (IdentifierInfo *II = New->getIdentifier()) 5576 if (!New->isInvalidDecl() && 5577 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 5578 II->isStr("FILE")) 5579 Context.setFILEDecl(New); 5580 5581 OwnedDecl = true; 5582 return DeclPtrTy::make(New); 5583} 5584 5585void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 5586 AdjustDeclIfTemplate(TagD); 5587 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5588 5589 // Enter the tag context. 5590 PushDeclContext(S, Tag); 5591} 5592 5593void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 5594 SourceLocation LBraceLoc) { 5595 AdjustDeclIfTemplate(TagD); 5596 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 5597 5598 FieldCollector->StartClass(); 5599 5600 if (!Record->getIdentifier()) 5601 return; 5602 5603 // C++ [class]p2: 5604 // [...] The class-name is also inserted into the scope of the 5605 // class itself; this is known as the injected-class-name. For 5606 // purposes of access checking, the injected-class-name is treated 5607 // as if it were a public member name. 5608 CXXRecordDecl *InjectedClassName 5609 = CXXRecordDecl::Create(Context, Record->getTagKind(), 5610 CurContext, Record->getLocation(), 5611 Record->getIdentifier(), 5612 Record->getTagKeywordLoc(), 5613 Record); 5614 InjectedClassName->setImplicit(); 5615 InjectedClassName->setAccess(AS_public); 5616 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 5617 InjectedClassName->setDescribedClassTemplate(Template); 5618 PushOnScopeChains(InjectedClassName, S); 5619 assert(InjectedClassName->isInjectedClassName() && 5620 "Broken injected-class-name"); 5621} 5622 5623void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 5624 SourceLocation RBraceLoc) { 5625 AdjustDeclIfTemplate(TagD); 5626 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5627 Tag->setRBraceLoc(RBraceLoc); 5628 5629 if (isa<CXXRecordDecl>(Tag)) 5630 FieldCollector->FinishClass(); 5631 5632 // Exit this scope of this tag's definition. 5633 PopDeclContext(); 5634 5635 // Notify the consumer that we've defined a tag. 5636 Consumer.HandleTagDeclDefinition(Tag); 5637} 5638 5639void Sema::ActOnTagDefinitionError(Scope *S, DeclPtrTy TagD) { 5640 AdjustDeclIfTemplate(TagD); 5641 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 5642 Tag->setInvalidDecl(); 5643 5644 // We're undoing ActOnTagStartDefinition here, not 5645 // ActOnStartCXXMemberDeclarations, so we don't have to mess with 5646 // the FieldCollector. 5647 5648 PopDeclContext(); 5649} 5650 5651// Note that FieldName may be null for anonymous bitfields. 5652bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 5653 QualType FieldTy, const Expr *BitWidth, 5654 bool *ZeroWidth) { 5655 // Default to true; that shouldn't confuse checks for emptiness 5656 if (ZeroWidth) 5657 *ZeroWidth = true; 5658 5659 // C99 6.7.2.1p4 - verify the field type. 5660 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 5661 if (!FieldTy->isDependentType() && !FieldTy->isIntegralOrEnumerationType()) { 5662 // Handle incomplete types with specific error. 5663 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5664 return true; 5665 if (FieldName) 5666 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5667 << FieldName << FieldTy << BitWidth->getSourceRange(); 5668 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5669 << FieldTy << BitWidth->getSourceRange(); 5670 } 5671 5672 // If the bit-width is type- or value-dependent, don't try to check 5673 // it now. 5674 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5675 return false; 5676 5677 llvm::APSInt Value; 5678 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5679 return true; 5680 5681 if (Value != 0 && ZeroWidth) 5682 *ZeroWidth = false; 5683 5684 // Zero-width bitfield is ok for anonymous field. 5685 if (Value == 0 && FieldName) 5686 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5687 5688 if (Value.isSigned() && Value.isNegative()) { 5689 if (FieldName) 5690 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5691 << FieldName << Value.toString(10); 5692 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5693 << Value.toString(10); 5694 } 5695 5696 if (!FieldTy->isDependentType()) { 5697 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5698 if (Value.getZExtValue() > TypeSize) { 5699 if (!getLangOptions().CPlusPlus) { 5700 if (FieldName) 5701 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5702 << FieldName << (unsigned)Value.getZExtValue() 5703 << (unsigned)TypeSize; 5704 5705 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5706 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5707 } 5708 5709 if (FieldName) 5710 Diag(FieldLoc, diag::warn_bitfield_width_exceeds_type_size) 5711 << FieldName << (unsigned)Value.getZExtValue() 5712 << (unsigned)TypeSize; 5713 else 5714 Diag(FieldLoc, diag::warn_anon_bitfield_width_exceeds_type_size) 5715 << (unsigned)Value.getZExtValue() << (unsigned)TypeSize; 5716 } 5717 } 5718 5719 return false; 5720} 5721 5722/// ActOnField - Each field of a struct/union/class is passed into this in order 5723/// to create a FieldDecl object for it. 5724Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5725 SourceLocation DeclStart, 5726 Declarator &D, ExprTy *BitfieldWidth) { 5727 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5728 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5729 AS_public); 5730 return DeclPtrTy::make(Res); 5731} 5732 5733/// HandleField - Analyze a field of a C struct or a C++ data member. 5734/// 5735FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5736 SourceLocation DeclStart, 5737 Declarator &D, Expr *BitWidth, 5738 AccessSpecifier AS) { 5739 IdentifierInfo *II = D.getIdentifier(); 5740 SourceLocation Loc = DeclStart; 5741 if (II) Loc = D.getIdentifierLoc(); 5742 5743 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 5744 QualType T = TInfo->getType(); 5745 if (getLangOptions().CPlusPlus) 5746 CheckExtraCXXDefaultArguments(D); 5747 5748 DiagnoseFunctionSpecifiers(D); 5749 5750 if (D.getDeclSpec().isThreadSpecified()) 5751 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5752 5753 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 5754 ForRedeclaration); 5755 5756 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5757 // Maybe we will complain about the shadowed template parameter. 5758 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5759 // Just pretend that we didn't see the previous declaration. 5760 PrevDecl = 0; 5761 } 5762 5763 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5764 PrevDecl = 0; 5765 5766 bool Mutable 5767 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5768 SourceLocation TSSL = D.getSourceRange().getBegin(); 5769 FieldDecl *NewFD 5770 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5771 AS, PrevDecl, &D); 5772 5773 if (NewFD->isInvalidDecl()) 5774 Record->setInvalidDecl(); 5775 5776 if (NewFD->isInvalidDecl() && PrevDecl) { 5777 // Don't introduce NewFD into scope; there's already something 5778 // with the same name in the same scope. 5779 } else if (II) { 5780 PushOnScopeChains(NewFD, S); 5781 } else 5782 Record->addDecl(NewFD); 5783 5784 return NewFD; 5785} 5786 5787/// \brief Build a new FieldDecl and check its well-formedness. 5788/// 5789/// This routine builds a new FieldDecl given the fields name, type, 5790/// record, etc. \p PrevDecl should refer to any previous declaration 5791/// with the same name and in the same scope as the field to be 5792/// created. 5793/// 5794/// \returns a new FieldDecl. 5795/// 5796/// \todo The Declarator argument is a hack. It will be removed once 5797FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5798 TypeSourceInfo *TInfo, 5799 RecordDecl *Record, SourceLocation Loc, 5800 bool Mutable, Expr *BitWidth, 5801 SourceLocation TSSL, 5802 AccessSpecifier AS, NamedDecl *PrevDecl, 5803 Declarator *D) { 5804 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5805 bool InvalidDecl = false; 5806 if (D) InvalidDecl = D->isInvalidType(); 5807 5808 // If we receive a broken type, recover by assuming 'int' and 5809 // marking this declaration as invalid. 5810 if (T.isNull()) { 5811 InvalidDecl = true; 5812 T = Context.IntTy; 5813 } 5814 5815 QualType EltTy = Context.getBaseElementType(T); 5816 if (!EltTy->isDependentType() && 5817 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5818 InvalidDecl = true; 5819 5820 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5821 // than a variably modified type. 5822 if (!InvalidDecl && T->isVariablyModifiedType()) { 5823 bool SizeIsNegative; 5824 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5825 SizeIsNegative); 5826 if (!FixedTy.isNull()) { 5827 Diag(Loc, diag::warn_illegal_constant_array_size); 5828 T = FixedTy; 5829 } else { 5830 if (SizeIsNegative) 5831 Diag(Loc, diag::err_typecheck_negative_array_size); 5832 else 5833 Diag(Loc, diag::err_typecheck_field_variable_size); 5834 InvalidDecl = true; 5835 } 5836 } 5837 5838 // Fields can not have abstract class types 5839 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5840 diag::err_abstract_type_in_decl, 5841 AbstractFieldType)) 5842 InvalidDecl = true; 5843 5844 bool ZeroWidth = false; 5845 // If this is declared as a bit-field, check the bit-field. 5846 if (!InvalidDecl && BitWidth && 5847 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5848 InvalidDecl = true; 5849 DeleteExpr(BitWidth); 5850 BitWidth = 0; 5851 ZeroWidth = false; 5852 } 5853 5854 // Check that 'mutable' is consistent with the type of the declaration. 5855 if (!InvalidDecl && Mutable) { 5856 unsigned DiagID = 0; 5857 if (T->isReferenceType()) 5858 DiagID = diag::err_mutable_reference; 5859 else if (T.isConstQualified()) 5860 DiagID = diag::err_mutable_const; 5861 5862 if (DiagID) { 5863 SourceLocation ErrLoc = Loc; 5864 if (D && D->getDeclSpec().getStorageClassSpecLoc().isValid()) 5865 ErrLoc = D->getDeclSpec().getStorageClassSpecLoc(); 5866 Diag(ErrLoc, DiagID); 5867 Mutable = false; 5868 InvalidDecl = true; 5869 } 5870 } 5871 5872 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5873 BitWidth, Mutable); 5874 if (InvalidDecl) 5875 NewFD->setInvalidDecl(); 5876 5877 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5878 Diag(Loc, diag::err_duplicate_member) << II; 5879 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5880 NewFD->setInvalidDecl(); 5881 } 5882 5883 if (!InvalidDecl && getLangOptions().CPlusPlus) { 5884 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5885 5886 if (!T->isPODType()) 5887 CXXRecord->setPOD(false); 5888 if (!ZeroWidth) 5889 CXXRecord->setEmpty(false); 5890 5891 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5892 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5893 if (RDecl->getDefinition()) { 5894 if (!RDecl->hasTrivialConstructor()) 5895 CXXRecord->setHasTrivialConstructor(false); 5896 if (!RDecl->hasTrivialCopyConstructor()) 5897 CXXRecord->setHasTrivialCopyConstructor(false); 5898 if (!RDecl->hasTrivialCopyAssignment()) 5899 CXXRecord->setHasTrivialCopyAssignment(false); 5900 if (!RDecl->hasTrivialDestructor()) 5901 CXXRecord->setHasTrivialDestructor(false); 5902 5903 // C++ 9.5p1: An object of a class with a non-trivial 5904 // constructor, a non-trivial copy constructor, a non-trivial 5905 // destructor, or a non-trivial copy assignment operator 5906 // cannot be a member of a union, nor can an array of such 5907 // objects. 5908 // TODO: C++0x alters this restriction significantly. 5909 if (Record->isUnion()) { 5910 // We check for copy constructors before constructors 5911 // because otherwise we'll never get complaints about 5912 // copy constructors. 5913 5914 CXXSpecialMember member = CXXInvalid; 5915 if (!RDecl->hasTrivialCopyConstructor()) 5916 member = CXXCopyConstructor; 5917 else if (!RDecl->hasTrivialConstructor()) 5918 member = CXXConstructor; 5919 else if (!RDecl->hasTrivialCopyAssignment()) 5920 member = CXXCopyAssignment; 5921 else if (!RDecl->hasTrivialDestructor()) 5922 member = CXXDestructor; 5923 5924 if (member != CXXInvalid) { 5925 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5926 DiagnoseNontrivial(RT, member); 5927 NewFD->setInvalidDecl(); 5928 } 5929 } 5930 } 5931 } 5932 } 5933 5934 // FIXME: We need to pass in the attributes given an AST 5935 // representation, not a parser representation. 5936 if (D) 5937 // FIXME: What to pass instead of TUScope? 5938 ProcessDeclAttributes(TUScope, NewFD, *D); 5939 5940 if (T.isObjCGCWeak()) 5941 Diag(Loc, diag::warn_attribute_weak_on_field); 5942 5943 NewFD->setAccess(AS); 5944 5945 // C++ [dcl.init.aggr]p1: 5946 // An aggregate is an array or a class (clause 9) with [...] no 5947 // private or protected non-static data members (clause 11). 5948 // A POD must be an aggregate. 5949 if (getLangOptions().CPlusPlus && 5950 (AS == AS_private || AS == AS_protected)) { 5951 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5952 CXXRecord->setAggregate(false); 5953 CXXRecord->setPOD(false); 5954 } 5955 5956 return NewFD; 5957} 5958 5959/// DiagnoseNontrivial - Given that a class has a non-trivial 5960/// special member, figure out why. 5961void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5962 QualType QT(T, 0U); 5963 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5964 5965 // Check whether the member was user-declared. 5966 switch (member) { 5967 case CXXInvalid: 5968 break; 5969 5970 case CXXConstructor: 5971 if (RD->hasUserDeclaredConstructor()) { 5972 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5973 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5974 const FunctionDecl *body = 0; 5975 ci->hasBody(body); 5976 if (!body || !cast<CXXConstructorDecl>(body)->isImplicitlyDefined()) { 5977 SourceLocation CtorLoc = ci->getLocation(); 5978 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5979 return; 5980 } 5981 } 5982 5983 assert(0 && "found no user-declared constructors"); 5984 return; 5985 } 5986 break; 5987 5988 case CXXCopyConstructor: 5989 if (RD->hasUserDeclaredCopyConstructor()) { 5990 SourceLocation CtorLoc = 5991 RD->getCopyConstructor(Context, 0)->getLocation(); 5992 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5993 return; 5994 } 5995 break; 5996 5997 case CXXCopyAssignment: 5998 if (RD->hasUserDeclaredCopyAssignment()) { 5999 // FIXME: this should use the location of the copy 6000 // assignment, not the type. 6001 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 6002 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 6003 return; 6004 } 6005 break; 6006 6007 case CXXDestructor: 6008 if (RD->hasUserDeclaredDestructor()) { 6009 SourceLocation DtorLoc = LookupDestructor(RD)->getLocation(); 6010 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 6011 return; 6012 } 6013 break; 6014 } 6015 6016 typedef CXXRecordDecl::base_class_iterator base_iter; 6017 6018 // Virtual bases and members inhibit trivial copying/construction, 6019 // but not trivial destruction. 6020 if (member != CXXDestructor) { 6021 // Check for virtual bases. vbases includes indirect virtual bases, 6022 // so we just iterate through the direct bases. 6023 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 6024 if (bi->isVirtual()) { 6025 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6026 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 6027 return; 6028 } 6029 6030 // Check for virtual methods. 6031 typedef CXXRecordDecl::method_iterator meth_iter; 6032 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 6033 ++mi) { 6034 if (mi->isVirtual()) { 6035 SourceLocation MLoc = mi->getSourceRange().getBegin(); 6036 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 6037 return; 6038 } 6039 } 6040 } 6041 6042 bool (CXXRecordDecl::*hasTrivial)() const; 6043 switch (member) { 6044 case CXXConstructor: 6045 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 6046 case CXXCopyConstructor: 6047 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 6048 case CXXCopyAssignment: 6049 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 6050 case CXXDestructor: 6051 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 6052 default: 6053 assert(0 && "unexpected special member"); return; 6054 } 6055 6056 // Check for nontrivial bases (and recurse). 6057 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 6058 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 6059 assert(BaseRT && "Don't know how to handle dependent bases"); 6060 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 6061 if (!(BaseRecTy->*hasTrivial)()) { 6062 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 6063 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 6064 DiagnoseNontrivial(BaseRT, member); 6065 return; 6066 } 6067 } 6068 6069 // Check for nontrivial members (and recurse). 6070 typedef RecordDecl::field_iterator field_iter; 6071 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 6072 ++fi) { 6073 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 6074 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 6075 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 6076 6077 if (!(EltRD->*hasTrivial)()) { 6078 SourceLocation FLoc = (*fi)->getLocation(); 6079 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 6080 DiagnoseNontrivial(EltRT, member); 6081 return; 6082 } 6083 } 6084 } 6085 6086 assert(0 && "found no explanation for non-trivial member"); 6087} 6088 6089/// TranslateIvarVisibility - Translate visibility from a token ID to an 6090/// AST enum value. 6091static ObjCIvarDecl::AccessControl 6092TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 6093 switch (ivarVisibility) { 6094 default: assert(0 && "Unknown visitibility kind"); 6095 case tok::objc_private: return ObjCIvarDecl::Private; 6096 case tok::objc_public: return ObjCIvarDecl::Public; 6097 case tok::objc_protected: return ObjCIvarDecl::Protected; 6098 case tok::objc_package: return ObjCIvarDecl::Package; 6099 } 6100} 6101 6102/// ActOnIvar - Each ivar field of an objective-c class is passed into this 6103/// in order to create an IvarDecl object for it. 6104Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 6105 SourceLocation DeclStart, 6106 DeclPtrTy IntfDecl, 6107 Declarator &D, ExprTy *BitfieldWidth, 6108 tok::ObjCKeywordKind Visibility) { 6109 6110 IdentifierInfo *II = D.getIdentifier(); 6111 Expr *BitWidth = (Expr*)BitfieldWidth; 6112 SourceLocation Loc = DeclStart; 6113 if (II) Loc = D.getIdentifierLoc(); 6114 6115 // FIXME: Unnamed fields can be handled in various different ways, for 6116 // example, unnamed unions inject all members into the struct namespace! 6117 6118 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S); 6119 QualType T = TInfo->getType(); 6120 6121 if (BitWidth) { 6122 // 6.7.2.1p3, 6.7.2.1p4 6123 if (VerifyBitField(Loc, II, T, BitWidth)) { 6124 D.setInvalidType(); 6125 DeleteExpr(BitWidth); 6126 BitWidth = 0; 6127 } 6128 } else { 6129 // Not a bitfield. 6130 6131 // validate II. 6132 6133 } 6134 if (T->isReferenceType()) { 6135 Diag(Loc, diag::err_ivar_reference_type); 6136 D.setInvalidType(); 6137 } 6138 // C99 6.7.2.1p8: A member of a structure or union may have any type other 6139 // than a variably modified type. 6140 else if (T->isVariablyModifiedType()) { 6141 Diag(Loc, diag::err_typecheck_ivar_variable_size); 6142 D.setInvalidType(); 6143 } 6144 6145 // Get the visibility (access control) for this ivar. 6146 ObjCIvarDecl::AccessControl ac = 6147 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 6148 : ObjCIvarDecl::None; 6149 // Must set ivar's DeclContext to its enclosing interface. 6150 ObjCContainerDecl *EnclosingDecl = IntfDecl.getAs<ObjCContainerDecl>(); 6151 ObjCContainerDecl *EnclosingContext; 6152 if (ObjCImplementationDecl *IMPDecl = 6153 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6154 // Case of ivar declared in an implementation. Context is that of its class. 6155 EnclosingContext = IMPDecl->getClassInterface(); 6156 assert(EnclosingContext && "Implementation has no class interface!"); 6157 } else { 6158 if (ObjCCategoryDecl *CDecl = 6159 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6160 if (!LangOpts.ObjCNonFragileABI2 || !CDecl->IsClassExtension()) { 6161 Diag(Loc, diag::err_misplaced_ivar) << CDecl->IsClassExtension(); 6162 return DeclPtrTy(); 6163 } 6164 } 6165 EnclosingContext = EnclosingDecl; 6166 } 6167 6168 // Construct the decl. 6169 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 6170 EnclosingContext, Loc, II, T, 6171 TInfo, ac, (Expr *)BitfieldWidth); 6172 6173 if (II) { 6174 NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName, 6175 ForRedeclaration); 6176 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 6177 && !isa<TagDecl>(PrevDecl)) { 6178 Diag(Loc, diag::err_duplicate_member) << II; 6179 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 6180 NewID->setInvalidDecl(); 6181 } 6182 } 6183 6184 // Process attributes attached to the ivar. 6185 ProcessDeclAttributes(S, NewID, D); 6186 6187 if (D.isInvalidType()) 6188 NewID->setInvalidDecl(); 6189 6190 if (II) { 6191 // FIXME: When interfaces are DeclContexts, we'll need to add 6192 // these to the interface. 6193 S->AddDecl(DeclPtrTy::make(NewID)); 6194 IdResolver.AddDecl(NewID); 6195 } 6196 6197 return DeclPtrTy::make(NewID); 6198} 6199 6200void Sema::ActOnFields(Scope* S, 6201 SourceLocation RecLoc, DeclPtrTy RecDecl, 6202 DeclPtrTy *Fields, unsigned NumFields, 6203 SourceLocation LBrac, SourceLocation RBrac, 6204 AttributeList *Attr) { 6205 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 6206 assert(EnclosingDecl && "missing record or interface decl"); 6207 6208 // If the decl this is being inserted into is invalid, then it may be a 6209 // redeclaration or some other bogus case. Don't try to add fields to it. 6210 if (EnclosingDecl->isInvalidDecl()) { 6211 // FIXME: Deallocate fields? 6212 return; 6213 } 6214 6215 6216 // Verify that all the fields are okay. 6217 unsigned NumNamedMembers = 0; 6218 llvm::SmallVector<FieldDecl*, 32> RecFields; 6219 6220 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 6221 for (unsigned i = 0; i != NumFields; ++i) { 6222 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 6223 6224 // Get the type for the field. 6225 Type *FDTy = FD->getType().getTypePtr(); 6226 6227 if (!FD->isAnonymousStructOrUnion()) { 6228 // Remember all fields written by the user. 6229 RecFields.push_back(FD); 6230 } 6231 6232 // If the field is already invalid for some reason, don't emit more 6233 // diagnostics about it. 6234 if (FD->isInvalidDecl()) { 6235 EnclosingDecl->setInvalidDecl(); 6236 continue; 6237 } 6238 6239 // C99 6.7.2.1p2: 6240 // A structure or union shall not contain a member with 6241 // incomplete or function type (hence, a structure shall not 6242 // contain an instance of itself, but may contain a pointer to 6243 // an instance of itself), except that the last member of a 6244 // structure with more than one named member may have incomplete 6245 // array type; such a structure (and any union containing, 6246 // possibly recursively, a member that is such a structure) 6247 // shall not be a member of a structure or an element of an 6248 // array. 6249 if (FDTy->isFunctionType()) { 6250 // Field declared as a function. 6251 Diag(FD->getLocation(), diag::err_field_declared_as_function) 6252 << FD->getDeclName(); 6253 FD->setInvalidDecl(); 6254 EnclosingDecl->setInvalidDecl(); 6255 continue; 6256 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 6257 Record && Record->isStruct()) { 6258 // Flexible array member. 6259 if (NumNamedMembers < 1) { 6260 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 6261 << FD->getDeclName(); 6262 FD->setInvalidDecl(); 6263 EnclosingDecl->setInvalidDecl(); 6264 continue; 6265 } 6266 if (!FD->getType()->isDependentType() && 6267 !Context.getBaseElementType(FD->getType())->isPODType()) { 6268 Diag(FD->getLocation(), diag::err_flexible_array_has_nonpod_type) 6269 << FD->getDeclName() << FD->getType(); 6270 FD->setInvalidDecl(); 6271 EnclosingDecl->setInvalidDecl(); 6272 continue; 6273 } 6274 6275 // Okay, we have a legal flexible array member at the end of the struct. 6276 if (Record) 6277 Record->setHasFlexibleArrayMember(true); 6278 } else if (!FDTy->isDependentType() && 6279 RequireCompleteType(FD->getLocation(), FD->getType(), 6280 diag::err_field_incomplete)) { 6281 // Incomplete type 6282 FD->setInvalidDecl(); 6283 EnclosingDecl->setInvalidDecl(); 6284 continue; 6285 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 6286 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 6287 // If this is a member of a union, then entire union becomes "flexible". 6288 if (Record && Record->isUnion()) { 6289 Record->setHasFlexibleArrayMember(true); 6290 } else { 6291 // If this is a struct/class and this is not the last element, reject 6292 // it. Note that GCC supports variable sized arrays in the middle of 6293 // structures. 6294 if (i != NumFields-1) 6295 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 6296 << FD->getDeclName() << FD->getType(); 6297 else { 6298 // We support flexible arrays at the end of structs in 6299 // other structs as an extension. 6300 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 6301 << FD->getDeclName(); 6302 if (Record) 6303 Record->setHasFlexibleArrayMember(true); 6304 } 6305 } 6306 } 6307 if (Record && FDTTy->getDecl()->hasObjectMember()) 6308 Record->setHasObjectMember(true); 6309 } else if (FDTy->isObjCObjectType()) { 6310 /// A field cannot be an Objective-c object 6311 Diag(FD->getLocation(), diag::err_statically_allocated_object); 6312 FD->setInvalidDecl(); 6313 EnclosingDecl->setInvalidDecl(); 6314 continue; 6315 } else if (getLangOptions().ObjC1 && 6316 getLangOptions().getGCMode() != LangOptions::NonGC && 6317 Record && 6318 (FD->getType()->isObjCObjectPointerType() || 6319 FD->getType().isObjCGCStrong())) 6320 Record->setHasObjectMember(true); 6321 else if (Context.getAsArrayType(FD->getType())) { 6322 QualType BaseType = Context.getBaseElementType(FD->getType()); 6323 if (Record && BaseType->isRecordType() && 6324 BaseType->getAs<RecordType>()->getDecl()->hasObjectMember()) 6325 Record->setHasObjectMember(true); 6326 } 6327 // Keep track of the number of named members. 6328 if (FD->getIdentifier()) 6329 ++NumNamedMembers; 6330 } 6331 6332 // Okay, we successfully defined 'Record'. 6333 if (Record) { 6334 Record->completeDefinition(); 6335 } else { 6336 ObjCIvarDecl **ClsFields = 6337 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 6338 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 6339 ID->setLocEnd(RBrac); 6340 // Add ivar's to class's DeclContext. 6341 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6342 ClsFields[i]->setLexicalDeclContext(ID); 6343 ID->addDecl(ClsFields[i]); 6344 } 6345 // Must enforce the rule that ivars in the base classes may not be 6346 // duplicates. 6347 if (ID->getSuperClass()) 6348 DiagnoseDuplicateIvars(ID, ID->getSuperClass()); 6349 } else if (ObjCImplementationDecl *IMPDecl = 6350 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 6351 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 6352 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 6353 // Ivar declared in @implementation never belongs to the implementation. 6354 // Only it is in implementation's lexical context. 6355 ClsFields[I]->setLexicalDeclContext(IMPDecl); 6356 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 6357 } else if (ObjCCategoryDecl *CDecl = 6358 dyn_cast<ObjCCategoryDecl>(EnclosingDecl)) { 6359 // case of ivars in class extension; all other cases have been 6360 // reported as errors elsewhere. 6361 // FIXME. Class extension does not have a LocEnd field. 6362 // CDecl->setLocEnd(RBrac); 6363 // Add ivar's to class extension's DeclContext. 6364 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 6365 ClsFields[i]->setLexicalDeclContext(CDecl); 6366 CDecl->addDecl(ClsFields[i]); 6367 } 6368 } 6369 } 6370 6371 if (Attr) 6372 ProcessDeclAttributeList(S, Record, Attr); 6373} 6374 6375/// \brief Determine whether the given integral value is representable within 6376/// the given type T. 6377static bool isRepresentableIntegerValue(ASTContext &Context, 6378 llvm::APSInt &Value, 6379 QualType T) { 6380 assert(T->isIntegralType(Context) && "Integral type required!"); 6381 unsigned BitWidth = Context.getIntWidth(T); 6382 6383 if (Value.isUnsigned() || Value.isNonNegative()) 6384 return Value.getActiveBits() < BitWidth; 6385 6386 return Value.getMinSignedBits() <= BitWidth; 6387} 6388 6389// \brief Given an integral type, return the next larger integral type 6390// (or a NULL type of no such type exists). 6391static QualType getNextLargerIntegralType(ASTContext &Context, QualType T) { 6392 // FIXME: Int128/UInt128 support, which also needs to be introduced into 6393 // enum checking below. 6394 assert(T->isIntegralType(Context) && "Integral type required!"); 6395 const unsigned NumTypes = 4; 6396 QualType SignedIntegralTypes[NumTypes] = { 6397 Context.ShortTy, Context.IntTy, Context.LongTy, Context.LongLongTy 6398 }; 6399 QualType UnsignedIntegralTypes[NumTypes] = { 6400 Context.UnsignedShortTy, Context.UnsignedIntTy, Context.UnsignedLongTy, 6401 Context.UnsignedLongLongTy 6402 }; 6403 6404 unsigned BitWidth = Context.getTypeSize(T); 6405 QualType *Types = T->isSignedIntegerType()? SignedIntegralTypes 6406 : UnsignedIntegralTypes; 6407 for (unsigned I = 0; I != NumTypes; ++I) 6408 if (Context.getTypeSize(Types[I]) > BitWidth) 6409 return Types[I]; 6410 6411 return QualType(); 6412} 6413 6414EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 6415 EnumConstantDecl *LastEnumConst, 6416 SourceLocation IdLoc, 6417 IdentifierInfo *Id, 6418 ExprArg val) { 6419 Expr *Val = (Expr *)val.get(); 6420 6421 unsigned IntWidth = Context.Target.getIntWidth(); 6422 llvm::APSInt EnumVal(IntWidth); 6423 QualType EltTy; 6424 if (Val) { 6425 if (Enum->isDependentType() || Val->isTypeDependent()) 6426 EltTy = Context.DependentTy; 6427 else { 6428 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 6429 SourceLocation ExpLoc; 6430 if (!Val->isValueDependent() && 6431 VerifyIntegerConstantExpression(Val, &EnumVal)) { 6432 Val = 0; 6433 } else { 6434 if (!getLangOptions().CPlusPlus) { 6435 // C99 6.7.2.2p2: 6436 // The expression that defines the value of an enumeration constant 6437 // shall be an integer constant expression that has a value 6438 // representable as an int. 6439 6440 // Complain if the value is not representable in an int. 6441 if (!isRepresentableIntegerValue(Context, EnumVal, Context.IntTy)) 6442 Diag(IdLoc, diag::ext_enum_value_not_int) 6443 << EnumVal.toString(10) << Val->getSourceRange() 6444 << (EnumVal.isUnsigned() || EnumVal.isNonNegative()); 6445 else if (!Context.hasSameType(Val->getType(), Context.IntTy)) { 6446 // Force the type of the expression to 'int'. 6447 ImpCastExprToType(Val, Context.IntTy, CastExpr::CK_IntegralCast); 6448 6449 if (Val != val.get()) { 6450 val.release(); 6451 val = Val; 6452 } 6453 } 6454 } 6455 6456 // C++0x [dcl.enum]p5: 6457 // If the underlying type is not fixed, the type of each enumerator 6458 // is the type of its initializing value: 6459 // - If an initializer is specified for an enumerator, the 6460 // initializing value has the same type as the expression. 6461 EltTy = Val->getType(); 6462 } 6463 } 6464 } 6465 6466 if (!Val) { 6467 if (Enum->isDependentType()) 6468 EltTy = Context.DependentTy; 6469 else if (!LastEnumConst) { 6470 // C++0x [dcl.enum]p5: 6471 // If the underlying type is not fixed, the type of each enumerator 6472 // is the type of its initializing value: 6473 // - If no initializer is specified for the first enumerator, the 6474 // initializing value has an unspecified integral type. 6475 // 6476 // GCC uses 'int' for its unspecified integral type, as does 6477 // C99 6.7.2.2p3. 6478 EltTy = Context.IntTy; 6479 } else { 6480 // Assign the last value + 1. 6481 EnumVal = LastEnumConst->getInitVal(); 6482 ++EnumVal; 6483 EltTy = LastEnumConst->getType(); 6484 6485 // Check for overflow on increment. 6486 if (EnumVal < LastEnumConst->getInitVal()) { 6487 // C++0x [dcl.enum]p5: 6488 // If the underlying type is not fixed, the type of each enumerator 6489 // is the type of its initializing value: 6490 // 6491 // - Otherwise the type of the initializing value is the same as 6492 // the type of the initializing value of the preceding enumerator 6493 // unless the incremented value is not representable in that type, 6494 // in which case the type is an unspecified integral type 6495 // sufficient to contain the incremented value. If no such type 6496 // exists, the program is ill-formed. 6497 QualType T = getNextLargerIntegralType(Context, EltTy); 6498 if (T.isNull()) { 6499 // There is no integral type larger enough to represent this 6500 // value. Complain, then allow the value to wrap around. 6501 EnumVal = LastEnumConst->getInitVal(); 6502 EnumVal.zext(EnumVal.getBitWidth() * 2); 6503 Diag(IdLoc, diag::warn_enumerator_too_large) 6504 << EnumVal.toString(10); 6505 } else { 6506 EltTy = T; 6507 } 6508 6509 // Retrieve the last enumerator's value, extent that type to the 6510 // type that is supposed to be large enough to represent the incremented 6511 // value, then increment. 6512 EnumVal = LastEnumConst->getInitVal(); 6513 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6514 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6515 ++EnumVal; 6516 6517 // If we're not in C++, diagnose the overflow of enumerator values, 6518 // which in C99 means that the enumerator value is not representable in 6519 // an int (C99 6.7.2.2p2). However, we support GCC's extension that 6520 // permits enumerator values that are representable in some larger 6521 // integral type. 6522 if (!getLangOptions().CPlusPlus && !T.isNull()) 6523 Diag(IdLoc, diag::warn_enum_value_overflow); 6524 } else if (!getLangOptions().CPlusPlus && 6525 !isRepresentableIntegerValue(Context, EnumVal, EltTy)) { 6526 // Enforce C99 6.7.2.2p2 even when we compute the next value. 6527 Diag(IdLoc, diag::ext_enum_value_not_int) 6528 << EnumVal.toString(10) << 1; 6529 } 6530 } 6531 } 6532 6533 if (!EltTy->isDependentType()) { 6534 // Make the enumerator value match the signedness and size of the 6535 // enumerator's type. 6536 EnumVal.zextOrTrunc(Context.getIntWidth(EltTy)); 6537 EnumVal.setIsSigned(EltTy->isSignedIntegerType()); 6538 } 6539 6540 val.release(); 6541 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 6542 Val, EnumVal); 6543} 6544 6545 6546Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 6547 DeclPtrTy lastEnumConst, 6548 SourceLocation IdLoc, 6549 IdentifierInfo *Id, 6550 SourceLocation EqualLoc, ExprTy *val) { 6551 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 6552 EnumConstantDecl *LastEnumConst = 6553 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 6554 Expr *Val = static_cast<Expr*>(val); 6555 6556 // The scope passed in may not be a decl scope. Zip up the scope tree until 6557 // we find one that is. 6558 S = getNonFieldDeclScope(S); 6559 6560 // Verify that there isn't already something declared with this name in this 6561 // scope. 6562 NamedDecl *PrevDecl = LookupSingleName(S, Id, IdLoc, LookupOrdinaryName, 6563 ForRedeclaration); 6564 if (PrevDecl && PrevDecl->isTemplateParameter()) { 6565 // Maybe we will complain about the shadowed template parameter. 6566 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 6567 // Just pretend that we didn't see the previous declaration. 6568 PrevDecl = 0; 6569 } 6570 6571 if (PrevDecl) { 6572 // When in C++, we may get a TagDecl with the same name; in this case the 6573 // enum constant will 'hide' the tag. 6574 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 6575 "Received TagDecl when not in C++!"); 6576 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 6577 if (isa<EnumConstantDecl>(PrevDecl)) 6578 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 6579 else 6580 Diag(IdLoc, diag::err_redefinition) << Id; 6581 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 6582 return DeclPtrTy(); 6583 } 6584 } 6585 6586 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 6587 IdLoc, Id, Owned(Val)); 6588 6589 // Register this decl in the current scope stack. 6590 if (New) { 6591 New->setAccess(TheEnumDecl->getAccess()); 6592 PushOnScopeChains(New, S); 6593 } 6594 6595 return DeclPtrTy::make(New); 6596} 6597 6598void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 6599 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 6600 DeclPtrTy *Elements, unsigned NumElements, 6601 Scope *S, AttributeList *Attr) { 6602 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 6603 QualType EnumType = Context.getTypeDeclType(Enum); 6604 6605 if (Attr) 6606 ProcessDeclAttributeList(S, Enum, Attr); 6607 6608 if (Enum->isDependentType()) { 6609 for (unsigned i = 0; i != NumElements; ++i) { 6610 EnumConstantDecl *ECD = 6611 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6612 if (!ECD) continue; 6613 6614 ECD->setType(EnumType); 6615 } 6616 6617 Enum->completeDefinition(Context.DependentTy, Context.DependentTy, 0, 0); 6618 return; 6619 } 6620 6621 // TODO: If the result value doesn't fit in an int, it must be a long or long 6622 // long value. ISO C does not support this, but GCC does as an extension, 6623 // emit a warning. 6624 unsigned IntWidth = Context.Target.getIntWidth(); 6625 unsigned CharWidth = Context.Target.getCharWidth(); 6626 unsigned ShortWidth = Context.Target.getShortWidth(); 6627 6628 // Verify that all the values are okay, compute the size of the values, and 6629 // reverse the list. 6630 unsigned NumNegativeBits = 0; 6631 unsigned NumPositiveBits = 0; 6632 6633 // Keep track of whether all elements have type int. 6634 bool AllElementsInt = true; 6635 6636 for (unsigned i = 0; i != NumElements; ++i) { 6637 EnumConstantDecl *ECD = 6638 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6639 if (!ECD) continue; // Already issued a diagnostic. 6640 6641 const llvm::APSInt &InitVal = ECD->getInitVal(); 6642 6643 // Keep track of the size of positive and negative values. 6644 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 6645 NumPositiveBits = std::max(NumPositiveBits, 6646 (unsigned)InitVal.getActiveBits()); 6647 else 6648 NumNegativeBits = std::max(NumNegativeBits, 6649 (unsigned)InitVal.getMinSignedBits()); 6650 6651 // Keep track of whether every enum element has type int (very commmon). 6652 if (AllElementsInt) 6653 AllElementsInt = ECD->getType() == Context.IntTy; 6654 } 6655 6656 // Figure out the type that should be used for this enum. 6657 // FIXME: Support -fshort-enums. 6658 QualType BestType; 6659 unsigned BestWidth; 6660 6661 // C++0x N3000 [conv.prom]p3: 6662 // An rvalue of an unscoped enumeration type whose underlying 6663 // type is not fixed can be converted to an rvalue of the first 6664 // of the following types that can represent all the values of 6665 // the enumeration: int, unsigned int, long int, unsigned long 6666 // int, long long int, or unsigned long long int. 6667 // C99 6.4.4.3p2: 6668 // An identifier declared as an enumeration constant has type int. 6669 // The C99 rule is modified by a gcc extension 6670 QualType BestPromotionType; 6671 6672 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 6673 6674 if (NumNegativeBits) { 6675 // If there is a negative value, figure out the smallest integer type (of 6676 // int/long/longlong) that fits. 6677 // If it's packed, check also if it fits a char or a short. 6678 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 6679 BestType = Context.SignedCharTy; 6680 BestWidth = CharWidth; 6681 } else if (Packed && NumNegativeBits <= ShortWidth && 6682 NumPositiveBits < ShortWidth) { 6683 BestType = Context.ShortTy; 6684 BestWidth = ShortWidth; 6685 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 6686 BestType = Context.IntTy; 6687 BestWidth = IntWidth; 6688 } else { 6689 BestWidth = Context.Target.getLongWidth(); 6690 6691 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 6692 BestType = Context.LongTy; 6693 } else { 6694 BestWidth = Context.Target.getLongLongWidth(); 6695 6696 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 6697 Diag(Enum->getLocation(), diag::warn_enum_too_large); 6698 BestType = Context.LongLongTy; 6699 } 6700 } 6701 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 6702 } else { 6703 // If there is no negative value, figure out the smallest type that fits 6704 // all of the enumerator values. 6705 // If it's packed, check also if it fits a char or a short. 6706 if (Packed && NumPositiveBits <= CharWidth) { 6707 BestType = Context.UnsignedCharTy; 6708 BestPromotionType = Context.IntTy; 6709 BestWidth = CharWidth; 6710 } else if (Packed && NumPositiveBits <= ShortWidth) { 6711 BestType = Context.UnsignedShortTy; 6712 BestPromotionType = Context.IntTy; 6713 BestWidth = ShortWidth; 6714 } else if (NumPositiveBits <= IntWidth) { 6715 BestType = Context.UnsignedIntTy; 6716 BestWidth = IntWidth; 6717 BestPromotionType 6718 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6719 ? Context.UnsignedIntTy : Context.IntTy; 6720 } else if (NumPositiveBits <= 6721 (BestWidth = Context.Target.getLongWidth())) { 6722 BestType = Context.UnsignedLongTy; 6723 BestPromotionType 6724 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6725 ? Context.UnsignedLongTy : Context.LongTy; 6726 } else { 6727 BestWidth = Context.Target.getLongLongWidth(); 6728 assert(NumPositiveBits <= BestWidth && 6729 "How could an initializer get larger than ULL?"); 6730 BestType = Context.UnsignedLongLongTy; 6731 BestPromotionType 6732 = (NumPositiveBits == BestWidth || !getLangOptions().CPlusPlus) 6733 ? Context.UnsignedLongLongTy : Context.LongLongTy; 6734 } 6735 } 6736 6737 // Loop over all of the enumerator constants, changing their types to match 6738 // the type of the enum if needed. 6739 for (unsigned i = 0; i != NumElements; ++i) { 6740 EnumConstantDecl *ECD = 6741 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 6742 if (!ECD) continue; // Already issued a diagnostic. 6743 6744 // Standard C says the enumerators have int type, but we allow, as an 6745 // extension, the enumerators to be larger than int size. If each 6746 // enumerator value fits in an int, type it as an int, otherwise type it the 6747 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 6748 // that X has type 'int', not 'unsigned'. 6749 6750 // Determine whether the value fits into an int. 6751 llvm::APSInt InitVal = ECD->getInitVal(); 6752 6753 // If it fits into an integer type, force it. Otherwise force it to match 6754 // the enum decl type. 6755 QualType NewTy; 6756 unsigned NewWidth; 6757 bool NewSign; 6758 if (!getLangOptions().CPlusPlus && 6759 isRepresentableIntegerValue(Context, InitVal, Context.IntTy)) { 6760 NewTy = Context.IntTy; 6761 NewWidth = IntWidth; 6762 NewSign = true; 6763 } else if (ECD->getType() == BestType) { 6764 // Already the right type! 6765 if (getLangOptions().CPlusPlus) 6766 // C++ [dcl.enum]p4: Following the closing brace of an 6767 // enum-specifier, each enumerator has the type of its 6768 // enumeration. 6769 ECD->setType(EnumType); 6770 continue; 6771 } else { 6772 NewTy = BestType; 6773 NewWidth = BestWidth; 6774 NewSign = BestType->isSignedIntegerType(); 6775 } 6776 6777 // Adjust the APSInt value. 6778 InitVal.extOrTrunc(NewWidth); 6779 InitVal.setIsSigned(NewSign); 6780 ECD->setInitVal(InitVal); 6781 6782 // Adjust the Expr initializer and type. 6783 if (ECD->getInitExpr()) 6784 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 6785 CastExpr::CK_IntegralCast, 6786 ECD->getInitExpr(), 6787 CXXBaseSpecifierArray(), 6788 ImplicitCastExpr::RValue)); 6789 if (getLangOptions().CPlusPlus) 6790 // C++ [dcl.enum]p4: Following the closing brace of an 6791 // enum-specifier, each enumerator has the type of its 6792 // enumeration. 6793 ECD->setType(EnumType); 6794 else 6795 ECD->setType(NewTy); 6796 } 6797 6798 Enum->completeDefinition(BestType, BestPromotionType, 6799 NumPositiveBits, NumNegativeBits); 6800} 6801 6802Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 6803 ExprArg expr) { 6804 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 6805 6806 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 6807 Loc, AsmString); 6808 CurContext->addDecl(New); 6809 return DeclPtrTy::make(New); 6810} 6811 6812void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6813 SourceLocation PragmaLoc, 6814 SourceLocation NameLoc) { 6815 Decl *PrevDecl = LookupSingleName(TUScope, Name, NameLoc, LookupOrdinaryName); 6816 6817 if (PrevDecl) { 6818 PrevDecl->addAttr(::new (Context) WeakAttr()); 6819 } else { 6820 (void)WeakUndeclaredIdentifiers.insert( 6821 std::pair<IdentifierInfo*,WeakInfo> 6822 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6823 } 6824} 6825 6826void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6827 IdentifierInfo* AliasName, 6828 SourceLocation PragmaLoc, 6829 SourceLocation NameLoc, 6830 SourceLocation AliasNameLoc) { 6831 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, AliasNameLoc, 6832 LookupOrdinaryName); 6833 WeakInfo W = WeakInfo(Name, NameLoc); 6834 6835 if (PrevDecl) { 6836 if (!PrevDecl->hasAttr<AliasAttr>()) 6837 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6838 DeclApplyPragmaWeak(TUScope, ND, W); 6839 } else { 6840 (void)WeakUndeclaredIdentifiers.insert( 6841 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6842 } 6843} 6844