SemaDecl.cpp revision 08fbf08fc4fc3816971556bad895d9c9d88966b7
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/Analysis/AnalysisContext.h" 18#include "clang/AST/APValue.h" 19#include "clang/AST/ASTConsumer.h" 20#include "clang/AST/ASTContext.h" 21#include "clang/AST/CXXInheritance.h" 22#include "clang/AST/DeclTemplate.h" 23#include "clang/AST/ExprCXX.h" 24#include "clang/AST/StmtCXX.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Parse/Template.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "clang/Basic/SourceManager.h" 30#include "clang/Basic/TargetInfo.h" 31// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 32#include "clang/Lex/Preprocessor.h" 33#include "clang/Lex/HeaderSearch.h" 34#include "llvm/ADT/Triple.h" 35#include <algorithm> 36#include <cstring> 37#include <functional> 38using namespace clang; 39 40/// getDeclName - Return a pretty name for the specified decl if possible, or 41/// an empty string if not. This is used for pretty crash reporting. 42std::string Sema::getDeclName(DeclPtrTy d) { 43 Decl *D = d.getAs<Decl>(); 44 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 45 return DN->getQualifiedNameAsString(); 46 return ""; 47} 48 49Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 50 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 51} 52 53/// \brief If the identifier refers to a type name within this scope, 54/// return the declaration of that type. 55/// 56/// This routine performs ordinary name lookup of the identifier II 57/// within the given scope, with optional C++ scope specifier SS, to 58/// determine whether the name refers to a type. If so, returns an 59/// opaque pointer (actually a QualType) corresponding to that 60/// type. Otherwise, returns NULL. 61/// 62/// If name lookup results in an ambiguity, this routine will complain 63/// and then return NULL. 64Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 65 Scope *S, const CXXScopeSpec *SS, 66 bool isClassName, 67 TypeTy *ObjectTypePtr) { 68 // Determine where we will perform name lookup. 69 DeclContext *LookupCtx = 0; 70 if (ObjectTypePtr) { 71 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 72 if (ObjectType->isRecordType()) 73 LookupCtx = computeDeclContext(ObjectType); 74 } else if (SS && SS->isSet()) { 75 LookupCtx = computeDeclContext(*SS, false); 76 77 if (!LookupCtx) { 78 if (isDependentScopeSpecifier(*SS)) { 79 // C++ [temp.res]p3: 80 // A qualified-id that refers to a type and in which the 81 // nested-name-specifier depends on a template-parameter (14.6.2) 82 // shall be prefixed by the keyword typename to indicate that the 83 // qualified-id denotes a type, forming an 84 // elaborated-type-specifier (7.1.5.3). 85 // 86 // We therefore do not perform any name lookup if the result would 87 // refer to a member of an unknown specialization. 88 if (!isClassName) 89 return 0; 90 91 // We know from the grammar that this name refers to a type, so build a 92 // TypenameType node to describe the type. 93 // FIXME: Record somewhere that this TypenameType node has no "typename" 94 // keyword associated with it. 95 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 96 II, SS->getRange()).getAsOpaquePtr(); 97 } 98 99 return 0; 100 } 101 102 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 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 // C++ [temp.local]p2: 192 // Within the scope of a class template specialization or 193 // partial specialization, when the injected-class-name is 194 // not followed by a <, it is equivalent to the 195 // injected-class-name followed by the template-argument s 196 // of the class template specialization or partial 197 // specialization enclosed in <>. 198 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 199 if (RD->isInjectedClassName()) 200 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 201 T = Template->getInjectedClassNameType(Context); 202 203 if (T.isNull()) 204 T = Context.getTypeDeclType(TD); 205 206 if (SS) 207 T = getQualifiedNameType(*SS, T); 208 209 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 210 T = Context.getObjCInterfaceType(IDecl); 211 } else if (UnresolvedUsingTypenameDecl *UUDecl = 212 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 213 // FIXME: preserve source structure information. 214 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 215 } else { 216 // If it's not plausibly a type, suppress diagnostics. 217 Result.suppressDiagnostics(); 218 return 0; 219 } 220 221 return T.getAsOpaquePtr(); 222} 223 224/// isTagName() - This method is called *for error recovery purposes only* 225/// to determine if the specified name is a valid tag name ("struct foo"). If 226/// so, this returns the TST for the tag corresponding to it (TST_enum, 227/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 228/// where the user forgot to specify the tag. 229DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 230 // Do a tag name lookup in this scope. 231 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 232 LookupName(R, S, false); 233 R.suppressDiagnostics(); 234 if (R.getResultKind() == LookupResult::Found) 235 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 236 switch (TD->getTagKind()) { 237 case TagDecl::TK_struct: return DeclSpec::TST_struct; 238 case TagDecl::TK_union: return DeclSpec::TST_union; 239 case TagDecl::TK_class: return DeclSpec::TST_class; 240 case TagDecl::TK_enum: return DeclSpec::TST_enum; 241 } 242 } 243 244 return DeclSpec::TST_unspecified; 245} 246 247bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 248 SourceLocation IILoc, 249 Scope *S, 250 const CXXScopeSpec *SS, 251 TypeTy *&SuggestedType) { 252 // We don't have anything to suggest (yet). 253 SuggestedType = 0; 254 255 // There may have been a typo in the name of the type. Look up typo 256 // results, in case we have something that we can suggest. 257 LookupResult Lookup(*this, &II, IILoc, LookupOrdinaryName, 258 NotForRedeclaration); 259 260 // FIXME: It would be nice if we could correct for typos in built-in 261 // names, such as "itn" for "int". 262 263 if (CorrectTypo(Lookup, S, SS) && Lookup.isSingleResult()) { 264 NamedDecl *Result = Lookup.getAsSingle<NamedDecl>(); 265 if ((isa<TypeDecl>(Result) || isa<ObjCInterfaceDecl>(Result)) && 266 !Result->isInvalidDecl()) { 267 // We found a similarly-named type or interface; suggest that. 268 if (!SS || !SS->isSet()) 269 Diag(IILoc, diag::err_unknown_typename_suggest) 270 << &II << Lookup.getLookupName() 271 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 272 Result->getNameAsString()); 273 else if (DeclContext *DC = computeDeclContext(*SS, false)) 274 Diag(IILoc, diag::err_unknown_nested_typename_suggest) 275 << &II << DC << Lookup.getLookupName() << SS->getRange() 276 << CodeModificationHint::CreateReplacement(SourceRange(IILoc), 277 Result->getNameAsString()); 278 else 279 llvm_unreachable("could not have corrected a typo here"); 280 281 Diag(Result->getLocation(), diag::note_previous_decl) 282 << Result->getDeclName(); 283 284 SuggestedType = getTypeName(*Result->getIdentifier(), IILoc, S, SS); 285 return true; 286 } 287 } 288 289 // FIXME: Should we move the logic that tries to recover from a missing tag 290 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 291 292 if (!SS || (!SS->isSet() && !SS->isInvalid())) 293 Diag(IILoc, diag::err_unknown_typename) << &II; 294 else if (DeclContext *DC = computeDeclContext(*SS, false)) 295 Diag(IILoc, diag::err_typename_nested_not_found) 296 << &II << DC << SS->getRange(); 297 else if (isDependentScopeSpecifier(*SS)) { 298 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 299 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 300 << SourceRange(SS->getRange().getBegin(), IILoc) 301 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 302 "typename "); 303 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 304 } else { 305 assert(SS && SS->isInvalid() && 306 "Invalid scope specifier has already been diagnosed"); 307 } 308 309 return true; 310} 311 312// Determines the context to return to after temporarily entering a 313// context. This depends in an unnecessarily complicated way on the 314// exact ordering of callbacks from the parser. 315DeclContext *Sema::getContainingDC(DeclContext *DC) { 316 317 // Functions defined inline within classes aren't parsed until we've 318 // finished parsing the top-level class, so the top-level class is 319 // the context we'll need to return to. 320 if (isa<FunctionDecl>(DC)) { 321 DC = DC->getLexicalParent(); 322 323 // A function not defined within a class will always return to its 324 // lexical context. 325 if (!isa<CXXRecordDecl>(DC)) 326 return DC; 327 328 // A C++ inline method/friend is parsed *after* the topmost class 329 // it was declared in is fully parsed ("complete"); the topmost 330 // class is the context we need to return to. 331 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 332 DC = RD; 333 334 // Return the declaration context of the topmost class the inline method is 335 // declared in. 336 return DC; 337 } 338 339 if (isa<ObjCMethodDecl>(DC)) 340 return Context.getTranslationUnitDecl(); 341 342 return DC->getLexicalParent(); 343} 344 345void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 346 assert(getContainingDC(DC) == CurContext && 347 "The next DeclContext should be lexically contained in the current one."); 348 CurContext = DC; 349 S->setEntity(DC); 350} 351 352void Sema::PopDeclContext() { 353 assert(CurContext && "DeclContext imbalance!"); 354 355 CurContext = getContainingDC(CurContext); 356} 357 358/// EnterDeclaratorContext - Used when we must lookup names in the context 359/// of a declarator's nested name specifier. 360/// 361void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 362 // C++0x [basic.lookup.unqual]p13: 363 // A name used in the definition of a static data member of class 364 // X (after the qualified-id of the static member) is looked up as 365 // if the name was used in a member function of X. 366 // C++0x [basic.lookup.unqual]p14: 367 // If a variable member of a namespace is defined outside of the 368 // scope of its namespace then any name used in the definition of 369 // the variable member (after the declarator-id) is looked up as 370 // if the definition of the variable member occurred in its 371 // namespace. 372 // Both of these imply that we should push a scope whose context 373 // is the semantic context of the declaration. We can't use 374 // PushDeclContext here because that context is not necessarily 375 // lexically contained in the current context. Fortunately, 376 // the containing scope should have the appropriate information. 377 378 assert(!S->getEntity() && "scope already has entity"); 379 380#ifndef NDEBUG 381 Scope *Ancestor = S->getParent(); 382 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 383 assert(Ancestor->getEntity() == CurContext && "ancestor context mismatch"); 384#endif 385 386 CurContext = DC; 387 S->setEntity(DC); 388} 389 390void Sema::ExitDeclaratorContext(Scope *S) { 391 assert(S->getEntity() == CurContext && "Context imbalance!"); 392 393 // Switch back to the lexical context. The safety of this is 394 // enforced by an assert in EnterDeclaratorContext. 395 Scope *Ancestor = S->getParent(); 396 while (!Ancestor->getEntity()) Ancestor = Ancestor->getParent(); 397 CurContext = (DeclContext*) Ancestor->getEntity(); 398 399 // We don't need to do anything with the scope, which is going to 400 // disappear. 401} 402 403/// \brief Determine whether we allow overloading of the function 404/// PrevDecl with another declaration. 405/// 406/// This routine determines whether overloading is possible, not 407/// whether some new function is actually an overload. It will return 408/// true in C++ (where we can always provide overloads) or, as an 409/// extension, in C when the previous function is already an 410/// overloaded function declaration or has the "overloadable" 411/// attribute. 412static bool AllowOverloadingOfFunction(LookupResult &Previous, 413 ASTContext &Context) { 414 if (Context.getLangOptions().CPlusPlus) 415 return true; 416 417 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 418 return true; 419 420 return (Previous.getResultKind() == LookupResult::Found 421 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 422} 423 424/// Add this decl to the scope shadowed decl chains. 425void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 426 // Move up the scope chain until we find the nearest enclosing 427 // non-transparent context. The declaration will be introduced into this 428 // scope. 429 while (S->getEntity() && 430 ((DeclContext *)S->getEntity())->isTransparentContext()) 431 S = S->getParent(); 432 433 // Add scoped declarations into their context, so that they can be 434 // found later. Declarations without a context won't be inserted 435 // into any context. 436 if (AddToContext) 437 CurContext->addDecl(D); 438 439 // Out-of-line function and variable definitions should not be pushed into 440 // scope. 441 if ((isa<FunctionTemplateDecl>(D) && 442 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 443 (isa<FunctionDecl>(D) && 444 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 445 cast<FunctionDecl>(D)->isOutOfLine())) || 446 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 447 return; 448 449 // If this replaces anything in the current scope, 450 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 451 IEnd = IdResolver.end(); 452 for (; I != IEnd; ++I) { 453 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 454 S->RemoveDecl(DeclPtrTy::make(*I)); 455 IdResolver.RemoveDecl(*I); 456 457 // Should only need to replace one decl. 458 break; 459 } 460 } 461 462 S->AddDecl(DeclPtrTy::make(D)); 463 IdResolver.AddDecl(D); 464} 465 466bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 467 return IdResolver.isDeclInScope(D, Ctx, Context, S); 468} 469 470static bool isOutOfScopePreviousDeclaration(NamedDecl *, 471 DeclContext*, 472 ASTContext&); 473 474/// Filters out lookup results that don't fall within the given scope 475/// as determined by isDeclInScope. 476static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 477 DeclContext *Ctx, Scope *S, 478 bool ConsiderLinkage) { 479 LookupResult::Filter F = R.makeFilter(); 480 while (F.hasNext()) { 481 NamedDecl *D = F.next(); 482 483 if (SemaRef.isDeclInScope(D, Ctx, S)) 484 continue; 485 486 if (ConsiderLinkage && 487 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 488 continue; 489 490 F.erase(); 491 } 492 493 F.done(); 494} 495 496static bool isUsingDecl(NamedDecl *D) { 497 return isa<UsingShadowDecl>(D) || 498 isa<UnresolvedUsingTypenameDecl>(D) || 499 isa<UnresolvedUsingValueDecl>(D); 500} 501 502/// Removes using shadow declarations from the lookup results. 503static void RemoveUsingDecls(LookupResult &R) { 504 LookupResult::Filter F = R.makeFilter(); 505 while (F.hasNext()) 506 if (isUsingDecl(F.next())) 507 F.erase(); 508 509 F.done(); 510} 511 512static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 513 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 514 return false; 515 516 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 517 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 518 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 519 if (!RD->hasTrivialConstructor()) 520 return false; 521 if (!RD->hasTrivialDestructor()) 522 return false; 523 } 524 } 525 } 526 527 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 528 !isa<ImplicitParamDecl>(D) && 529 D->getDeclContext()->isFunctionOrMethod()); 530} 531 532void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 533 if (S->decl_empty()) return; 534 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 535 "Scope shouldn't contain decls!"); 536 537 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 538 I != E; ++I) { 539 Decl *TmpD = (*I).getAs<Decl>(); 540 assert(TmpD && "This decl didn't get pushed??"); 541 542 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 543 NamedDecl *D = cast<NamedDecl>(TmpD); 544 545 if (!D->getDeclName()) continue; 546 547 // Diagnose unused variables in this scope. 548 if (ShouldDiagnoseUnusedDecl(D)) 549 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 550 551 // Remove this name from our lexical scope. 552 IdResolver.RemoveDecl(D); 553 } 554} 555 556/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 557/// return 0 if one not found. 558/// 559/// \param Id the name of the Objective-C class we're looking for. If 560/// typo-correction fixes this name, the Id will be updated 561/// to the fixed name. 562/// 563/// \param RecoverLoc if provided, this routine will attempt to 564/// recover from a typo in the name of an existing Objective-C class 565/// and, if successful, will return the lookup that results from 566/// typo-correction. 567ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *&Id, 568 SourceLocation RecoverLoc) { 569 // The third "scope" argument is 0 since we aren't enabling lazy built-in 570 // creation from this context. 571 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 572 573 if (!IDecl && !RecoverLoc.isInvalid()) { 574 // Perform typo correction at the given location, but only if we 575 // find an Objective-C class name. 576 LookupResult R(*this, Id, RecoverLoc, LookupOrdinaryName); 577 if (CorrectTypo(R, TUScope, 0) && 578 (IDecl = R.getAsSingle<ObjCInterfaceDecl>())) { 579 Diag(RecoverLoc, diag::err_undef_interface_suggest) 580 << Id << IDecl->getDeclName() 581 << CodeModificationHint::CreateReplacement(RecoverLoc, 582 IDecl->getNameAsString()); 583 Diag(IDecl->getLocation(), diag::note_previous_decl) 584 << IDecl->getDeclName(); 585 586 Id = IDecl->getIdentifier(); 587 } 588 } 589 590 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 591} 592 593/// getNonFieldDeclScope - Retrieves the innermost scope, starting 594/// from S, where a non-field would be declared. This routine copes 595/// with the difference between C and C++ scoping rules in structs and 596/// unions. For example, the following code is well-formed in C but 597/// ill-formed in C++: 598/// @code 599/// struct S6 { 600/// enum { BAR } e; 601/// }; 602/// 603/// void test_S6() { 604/// struct S6 a; 605/// a.e = BAR; 606/// } 607/// @endcode 608/// For the declaration of BAR, this routine will return a different 609/// scope. The scope S will be the scope of the unnamed enumeration 610/// within S6. In C++, this routine will return the scope associated 611/// with S6, because the enumeration's scope is a transparent 612/// context but structures can contain non-field names. In C, this 613/// routine will return the translation unit scope, since the 614/// enumeration's scope is a transparent context and structures cannot 615/// contain non-field names. 616Scope *Sema::getNonFieldDeclScope(Scope *S) { 617 while (((S->getFlags() & Scope::DeclScope) == 0) || 618 (S->getEntity() && 619 ((DeclContext *)S->getEntity())->isTransparentContext()) || 620 (S->isClassScope() && !getLangOptions().CPlusPlus)) 621 S = S->getParent(); 622 return S; 623} 624 625void Sema::InitBuiltinVaListType() { 626 if (!Context.getBuiltinVaListType().isNull()) 627 return; 628 629 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 630 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 631 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 632 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 633} 634 635/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 636/// file scope. lazily create a decl for it. ForRedeclaration is true 637/// if we're creating this built-in in anticipation of redeclaring the 638/// built-in. 639NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 640 Scope *S, bool ForRedeclaration, 641 SourceLocation Loc) { 642 Builtin::ID BID = (Builtin::ID)bid; 643 644 if (Context.BuiltinInfo.hasVAListUse(BID)) 645 InitBuiltinVaListType(); 646 647 ASTContext::GetBuiltinTypeError Error; 648 QualType R = Context.GetBuiltinType(BID, Error); 649 switch (Error) { 650 case ASTContext::GE_None: 651 // Okay 652 break; 653 654 case ASTContext::GE_Missing_stdio: 655 if (ForRedeclaration) 656 Diag(Loc, diag::err_implicit_decl_requires_stdio) 657 << Context.BuiltinInfo.GetName(BID); 658 return 0; 659 660 case ASTContext::GE_Missing_setjmp: 661 if (ForRedeclaration) 662 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 663 << Context.BuiltinInfo.GetName(BID); 664 return 0; 665 } 666 667 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 668 Diag(Loc, diag::ext_implicit_lib_function_decl) 669 << Context.BuiltinInfo.GetName(BID) 670 << R; 671 if (Context.BuiltinInfo.getHeaderName(BID) && 672 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 673 != Diagnostic::Ignored) 674 Diag(Loc, diag::note_please_include_header) 675 << Context.BuiltinInfo.getHeaderName(BID) 676 << Context.BuiltinInfo.GetName(BID); 677 } 678 679 FunctionDecl *New = FunctionDecl::Create(Context, 680 Context.getTranslationUnitDecl(), 681 Loc, II, R, /*TInfo=*/0, 682 FunctionDecl::Extern, false, 683 /*hasPrototype=*/true); 684 New->setImplicit(); 685 686 // Create Decl objects for each parameter, adding them to the 687 // FunctionDecl. 688 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 689 llvm::SmallVector<ParmVarDecl*, 16> Params; 690 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 691 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 692 FT->getArgType(i), /*TInfo=*/0, 693 VarDecl::None, 0)); 694 New->setParams(Context, Params.data(), Params.size()); 695 } 696 697 AddKnownFunctionAttributes(New); 698 699 // TUScope is the translation-unit scope to insert this function into. 700 // FIXME: This is hideous. We need to teach PushOnScopeChains to 701 // relate Scopes to DeclContexts, and probably eliminate CurContext 702 // entirely, but we're not there yet. 703 DeclContext *SavedContext = CurContext; 704 CurContext = Context.getTranslationUnitDecl(); 705 PushOnScopeChains(New, TUScope); 706 CurContext = SavedContext; 707 return New; 708} 709 710/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 711/// same name and scope as a previous declaration 'Old'. Figure out 712/// how to resolve this situation, merging decls or emitting 713/// diagnostics as appropriate. If there was an error, set New to be invalid. 714/// 715void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 716 // If the new decl is known invalid already, don't bother doing any 717 // merging checks. 718 if (New->isInvalidDecl()) return; 719 720 // Allow multiple definitions for ObjC built-in typedefs. 721 // FIXME: Verify the underlying types are equivalent! 722 if (getLangOptions().ObjC1) { 723 const IdentifierInfo *TypeID = New->getIdentifier(); 724 switch (TypeID->getLength()) { 725 default: break; 726 case 2: 727 if (!TypeID->isStr("id")) 728 break; 729 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 730 // Install the built-in type for 'id', ignoring the current definition. 731 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 732 return; 733 case 5: 734 if (!TypeID->isStr("Class")) 735 break; 736 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 737 // Install the built-in type for 'Class', ignoring the current definition. 738 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 739 return; 740 case 3: 741 if (!TypeID->isStr("SEL")) 742 break; 743 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 744 // Install the built-in type for 'SEL', ignoring the current definition. 745 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 746 return; 747 case 8: 748 if (!TypeID->isStr("Protocol")) 749 break; 750 Context.setObjCProtoType(New->getUnderlyingType()); 751 return; 752 } 753 // Fall through - the typedef name was not a builtin type. 754 } 755 756 // Verify the old decl was also a type. 757 TypeDecl *Old = OldDecls.getAsSingle<TypeDecl>(); 758 if (!Old) { 759 Diag(New->getLocation(), diag::err_redefinition_different_kind) 760 << New->getDeclName(); 761 762 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 763 if (OldD->getLocation().isValid()) 764 Diag(OldD->getLocation(), diag::note_previous_definition); 765 766 return New->setInvalidDecl(); 767 } 768 769 // If the old declaration is invalid, just give up here. 770 if (Old->isInvalidDecl()) 771 return New->setInvalidDecl(); 772 773 // Determine the "old" type we'll use for checking and diagnostics. 774 QualType OldType; 775 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 776 OldType = OldTypedef->getUnderlyingType(); 777 else 778 OldType = Context.getTypeDeclType(Old); 779 780 // If the typedef types are not identical, reject them in all languages and 781 // with any extensions enabled. 782 783 if (OldType != New->getUnderlyingType() && 784 Context.getCanonicalType(OldType) != 785 Context.getCanonicalType(New->getUnderlyingType())) { 786 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 787 << New->getUnderlyingType() << OldType; 788 if (Old->getLocation().isValid()) 789 Diag(Old->getLocation(), diag::note_previous_definition); 790 return New->setInvalidDecl(); 791 } 792 793 // The types match. Link up the redeclaration chain if the old 794 // declaration was a typedef. 795 // FIXME: this is a potential source of wierdness if the type 796 // spellings don't match exactly. 797 if (isa<TypedefDecl>(Old)) 798 New->setPreviousDeclaration(cast<TypedefDecl>(Old)); 799 800 if (getLangOptions().Microsoft) 801 return; 802 803 if (getLangOptions().CPlusPlus) { 804 // C++ [dcl.typedef]p2: 805 // In a given non-class scope, a typedef specifier can be used to 806 // redefine the name of any type declared in that scope to refer 807 // to the type to which it already refers. 808 if (!isa<CXXRecordDecl>(CurContext)) 809 return; 810 811 // C++0x [dcl.typedef]p4: 812 // In a given class scope, a typedef specifier can be used to redefine 813 // any class-name declared in that scope that is not also a typedef-name 814 // to refer to the type to which it already refers. 815 // 816 // This wording came in via DR424, which was a correction to the 817 // wording in DR56, which accidentally banned code like: 818 // 819 // struct S { 820 // typedef struct A { } A; 821 // }; 822 // 823 // in the C++03 standard. We implement the C++0x semantics, which 824 // allow the above but disallow 825 // 826 // struct S { 827 // typedef int I; 828 // typedef int I; 829 // }; 830 // 831 // since that was the intent of DR56. 832 if (!isa<TypedefDecl >(Old)) 833 return; 834 835 Diag(New->getLocation(), diag::err_redefinition) 836 << New->getDeclName(); 837 Diag(Old->getLocation(), diag::note_previous_definition); 838 return New->setInvalidDecl(); 839 } 840 841 // If we have a redefinition of a typedef in C, emit a warning. This warning 842 // is normally mapped to an error, but can be controlled with 843 // -Wtypedef-redefinition. If either the original or the redefinition is 844 // in a system header, don't emit this for compatibility with GCC. 845 if (PP.getDiagnostics().getSuppressSystemWarnings() && 846 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 847 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 848 return; 849 850 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 851 << New->getDeclName(); 852 Diag(Old->getLocation(), diag::note_previous_definition); 853 return; 854} 855 856/// DeclhasAttr - returns true if decl Declaration already has the target 857/// attribute. 858static bool 859DeclHasAttr(const Decl *decl, const Attr *target) { 860 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 861 if (attr->getKind() == target->getKind()) 862 return true; 863 864 return false; 865} 866 867/// MergeAttributes - append attributes from the Old decl to the New one. 868static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 869 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 870 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 871 Attr *NewAttr = attr->clone(C); 872 NewAttr->setInherited(true); 873 New->addAttr(NewAttr); 874 } 875 } 876} 877 878/// Used in MergeFunctionDecl to keep track of function parameters in 879/// C. 880struct GNUCompatibleParamWarning { 881 ParmVarDecl *OldParm; 882 ParmVarDecl *NewParm; 883 QualType PromotedType; 884}; 885 886 887/// getSpecialMember - get the special member enum for a method. 888static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 889 const CXXMethodDecl *MD) { 890 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 891 if (Ctor->isDefaultConstructor()) 892 return Sema::CXXDefaultConstructor; 893 if (Ctor->isCopyConstructor()) 894 return Sema::CXXCopyConstructor; 895 } 896 897 if (isa<CXXDestructorDecl>(MD)) 898 return Sema::CXXDestructor; 899 900 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 901 return Sema::CXXCopyAssignment; 902} 903 904/// MergeFunctionDecl - We just parsed a function 'New' from 905/// declarator D which has the same name and scope as a previous 906/// declaration 'Old'. Figure out how to resolve this situation, 907/// merging decls or emitting diagnostics as appropriate. 908/// 909/// In C++, New and Old must be declarations that are not 910/// overloaded. Use IsOverload to determine whether New and Old are 911/// overloaded, and to select the Old declaration that New should be 912/// merged with. 913/// 914/// Returns true if there was an error, false otherwise. 915bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 916 // Verify the old decl was also a function. 917 FunctionDecl *Old = 0; 918 if (FunctionTemplateDecl *OldFunctionTemplate 919 = dyn_cast<FunctionTemplateDecl>(OldD)) 920 Old = OldFunctionTemplate->getTemplatedDecl(); 921 else 922 Old = dyn_cast<FunctionDecl>(OldD); 923 if (!Old) { 924 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 925 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 926 Diag(Shadow->getTargetDecl()->getLocation(), 927 diag::note_using_decl_target); 928 Diag(Shadow->getUsingDecl()->getLocation(), 929 diag::note_using_decl) << 0; 930 return true; 931 } 932 933 Diag(New->getLocation(), diag::err_redefinition_different_kind) 934 << New->getDeclName(); 935 Diag(OldD->getLocation(), diag::note_previous_definition); 936 return true; 937 } 938 939 // Determine whether the previous declaration was a definition, 940 // implicit declaration, or a declaration. 941 diag::kind PrevDiag; 942 if (Old->isThisDeclarationADefinition()) 943 PrevDiag = diag::note_previous_definition; 944 else if (Old->isImplicit()) 945 PrevDiag = diag::note_previous_implicit_declaration; 946 else 947 PrevDiag = diag::note_previous_declaration; 948 949 QualType OldQType = Context.getCanonicalType(Old->getType()); 950 QualType NewQType = Context.getCanonicalType(New->getType()); 951 952 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 953 New->getStorageClass() == FunctionDecl::Static && 954 Old->getStorageClass() != FunctionDecl::Static) { 955 Diag(New->getLocation(), diag::err_static_non_static) 956 << New; 957 Diag(Old->getLocation(), PrevDiag); 958 return true; 959 } 960 961 if (getLangOptions().CPlusPlus) { 962 // (C++98 13.1p2): 963 // Certain function declarations cannot be overloaded: 964 // -- Function declarations that differ only in the return type 965 // cannot be overloaded. 966 QualType OldReturnType 967 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 968 QualType NewReturnType 969 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 970 if (OldReturnType != NewReturnType) { 971 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 972 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 973 return true; 974 } 975 976 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 977 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 978 if (OldMethod && NewMethod) { 979 if (!NewMethod->getFriendObjectKind() && 980 NewMethod->getLexicalDeclContext()->isRecord()) { 981 // -- Member function declarations with the same name and the 982 // same parameter types cannot be overloaded if any of them 983 // is a static member function declaration. 984 if (OldMethod->isStatic() || NewMethod->isStatic()) { 985 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 986 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 987 return true; 988 } 989 990 // C++ [class.mem]p1: 991 // [...] A member shall not be declared twice in the 992 // member-specification, except that a nested class or member 993 // class template can be declared and then later defined. 994 unsigned NewDiag; 995 if (isa<CXXConstructorDecl>(OldMethod)) 996 NewDiag = diag::err_constructor_redeclared; 997 else if (isa<CXXDestructorDecl>(NewMethod)) 998 NewDiag = diag::err_destructor_redeclared; 999 else if (isa<CXXConversionDecl>(NewMethod)) 1000 NewDiag = diag::err_conv_function_redeclared; 1001 else 1002 NewDiag = diag::err_member_redeclared; 1003 1004 Diag(New->getLocation(), NewDiag); 1005 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1006 } else { 1007 if (OldMethod->isImplicit()) { 1008 Diag(NewMethod->getLocation(), 1009 diag::err_definition_of_implicitly_declared_member) 1010 << New << getSpecialMember(Context, OldMethod); 1011 1012 Diag(OldMethod->getLocation(), 1013 diag::note_previous_implicit_declaration); 1014 return true; 1015 } 1016 } 1017 } 1018 1019 // (C++98 8.3.5p3): 1020 // All declarations for a function shall agree exactly in both the 1021 // return type and the parameter-type-list. 1022 // attributes should be ignored when comparing. 1023 if (Context.getNoReturnType(OldQType, false) == 1024 Context.getNoReturnType(NewQType, false)) 1025 return MergeCompatibleFunctionDecls(New, Old); 1026 1027 // Fall through for conflicting redeclarations and redefinitions. 1028 } 1029 1030 // C: Function types need to be compatible, not identical. This handles 1031 // duplicate function decls like "void f(int); void f(enum X);" properly. 1032 if (!getLangOptions().CPlusPlus && 1033 Context.typesAreCompatible(OldQType, NewQType)) { 1034 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 1035 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 1036 const FunctionProtoType *OldProto = 0; 1037 if (isa<FunctionNoProtoType>(NewFuncType) && 1038 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 1039 // The old declaration provided a function prototype, but the 1040 // new declaration does not. Merge in the prototype. 1041 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 1042 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 1043 OldProto->arg_type_end()); 1044 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 1045 ParamTypes.data(), ParamTypes.size(), 1046 OldProto->isVariadic(), 1047 OldProto->getTypeQuals()); 1048 New->setType(NewQType); 1049 New->setHasInheritedPrototype(); 1050 1051 // Synthesize a parameter for each argument type. 1052 llvm::SmallVector<ParmVarDecl*, 16> Params; 1053 for (FunctionProtoType::arg_type_iterator 1054 ParamType = OldProto->arg_type_begin(), 1055 ParamEnd = OldProto->arg_type_end(); 1056 ParamType != ParamEnd; ++ParamType) { 1057 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 1058 SourceLocation(), 0, 1059 *ParamType, /*TInfo=*/0, 1060 VarDecl::None, 0); 1061 Param->setImplicit(); 1062 Params.push_back(Param); 1063 } 1064 1065 New->setParams(Context, Params.data(), Params.size()); 1066 } 1067 1068 return MergeCompatibleFunctionDecls(New, Old); 1069 } 1070 1071 // GNU C permits a K&R definition to follow a prototype declaration 1072 // if the declared types of the parameters in the K&R definition 1073 // match the types in the prototype declaration, even when the 1074 // promoted types of the parameters from the K&R definition differ 1075 // from the types in the prototype. GCC then keeps the types from 1076 // the prototype. 1077 // 1078 // If a variadic prototype is followed by a non-variadic K&R definition, 1079 // the K&R definition becomes variadic. This is sort of an edge case, but 1080 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 1081 // C99 6.9.1p8. 1082 if (!getLangOptions().CPlusPlus && 1083 Old->hasPrototype() && !New->hasPrototype() && 1084 New->getType()->getAs<FunctionProtoType>() && 1085 Old->getNumParams() == New->getNumParams()) { 1086 llvm::SmallVector<QualType, 16> ArgTypes; 1087 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 1088 const FunctionProtoType *OldProto 1089 = Old->getType()->getAs<FunctionProtoType>(); 1090 const FunctionProtoType *NewProto 1091 = New->getType()->getAs<FunctionProtoType>(); 1092 1093 // Determine whether this is the GNU C extension. 1094 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 1095 NewProto->getResultType()); 1096 bool LooseCompatible = !MergedReturn.isNull(); 1097 for (unsigned Idx = 0, End = Old->getNumParams(); 1098 LooseCompatible && Idx != End; ++Idx) { 1099 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 1100 ParmVarDecl *NewParm = New->getParamDecl(Idx); 1101 if (Context.typesAreCompatible(OldParm->getType(), 1102 NewProto->getArgType(Idx))) { 1103 ArgTypes.push_back(NewParm->getType()); 1104 } else if (Context.typesAreCompatible(OldParm->getType(), 1105 NewParm->getType())) { 1106 GNUCompatibleParamWarning Warn 1107 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 1108 Warnings.push_back(Warn); 1109 ArgTypes.push_back(NewParm->getType()); 1110 } else 1111 LooseCompatible = false; 1112 } 1113 1114 if (LooseCompatible) { 1115 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 1116 Diag(Warnings[Warn].NewParm->getLocation(), 1117 diag::ext_param_promoted_not_compatible_with_prototype) 1118 << Warnings[Warn].PromotedType 1119 << Warnings[Warn].OldParm->getType(); 1120 Diag(Warnings[Warn].OldParm->getLocation(), 1121 diag::note_previous_declaration); 1122 } 1123 1124 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1125 ArgTypes.size(), 1126 OldProto->isVariadic(), 0)); 1127 return MergeCompatibleFunctionDecls(New, Old); 1128 } 1129 1130 // Fall through to diagnose conflicting types. 1131 } 1132 1133 // A function that has already been declared has been redeclared or defined 1134 // with a different type- show appropriate diagnostic 1135 if (unsigned BuiltinID = Old->getBuiltinID()) { 1136 // The user has declared a builtin function with an incompatible 1137 // signature. 1138 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1139 // The function the user is redeclaring is a library-defined 1140 // function like 'malloc' or 'printf'. Warn about the 1141 // redeclaration, then pretend that we don't know about this 1142 // library built-in. 1143 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1144 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1145 << Old << Old->getType(); 1146 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1147 Old->setInvalidDecl(); 1148 return false; 1149 } 1150 1151 PrevDiag = diag::note_previous_builtin_declaration; 1152 } 1153 1154 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1155 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1156 return true; 1157} 1158 1159/// \brief Completes the merge of two function declarations that are 1160/// known to be compatible. 1161/// 1162/// This routine handles the merging of attributes and other 1163/// properties of function declarations form the old declaration to 1164/// the new declaration, once we know that New is in fact a 1165/// redeclaration of Old. 1166/// 1167/// \returns false 1168bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1169 // Merge the attributes 1170 MergeAttributes(New, Old, Context); 1171 1172 // Merge the storage class. 1173 if (Old->getStorageClass() != FunctionDecl::Extern && 1174 Old->getStorageClass() != FunctionDecl::None) 1175 New->setStorageClass(Old->getStorageClass()); 1176 1177 // Merge "pure" flag. 1178 if (Old->isPure()) 1179 New->setPure(); 1180 1181 // Merge the "deleted" flag. 1182 if (Old->isDeleted()) 1183 New->setDeleted(); 1184 1185 if (getLangOptions().CPlusPlus) 1186 return MergeCXXFunctionDecl(New, Old); 1187 1188 return false; 1189} 1190 1191/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1192/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1193/// situation, merging decls or emitting diagnostics as appropriate. 1194/// 1195/// Tentative definition rules (C99 6.9.2p2) are checked by 1196/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1197/// definitions here, since the initializer hasn't been attached. 1198/// 1199void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1200 // If the new decl is already invalid, don't do any other checking. 1201 if (New->isInvalidDecl()) 1202 return; 1203 1204 // Verify the old decl was also a variable. 1205 VarDecl *Old = 0; 1206 if (!Previous.isSingleResult() || 1207 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1208 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1209 << New->getDeclName(); 1210 Diag(Previous.getRepresentativeDecl()->getLocation(), 1211 diag::note_previous_definition); 1212 return New->setInvalidDecl(); 1213 } 1214 1215 MergeAttributes(New, Old, Context); 1216 1217 // Merge the types 1218 QualType MergedT; 1219 if (getLangOptions().CPlusPlus) { 1220 if (Context.hasSameType(New->getType(), Old->getType())) 1221 MergedT = New->getType(); 1222 // C++ [basic.link]p10: 1223 // [...] the types specified by all declarations referring to a given 1224 // object or function shall be identical, except that declarations for an 1225 // array object can specify array types that differ by the presence or 1226 // absence of a major array bound (8.3.4). 1227 else if (Old->getType()->isIncompleteArrayType() && 1228 New->getType()->isArrayType()) { 1229 CanQual<ArrayType> OldArray 1230 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1231 CanQual<ArrayType> NewArray 1232 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1233 if (OldArray->getElementType() == NewArray->getElementType()) 1234 MergedT = New->getType(); 1235 } else if (Old->getType()->isArrayType() && 1236 New->getType()->isIncompleteArrayType()) { 1237 CanQual<ArrayType> OldArray 1238 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1239 CanQual<ArrayType> NewArray 1240 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1241 if (OldArray->getElementType() == NewArray->getElementType()) 1242 MergedT = Old->getType(); 1243 } 1244 } else { 1245 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1246 } 1247 if (MergedT.isNull()) { 1248 Diag(New->getLocation(), diag::err_redefinition_different_type) 1249 << New->getDeclName(); 1250 Diag(Old->getLocation(), diag::note_previous_definition); 1251 return New->setInvalidDecl(); 1252 } 1253 New->setType(MergedT); 1254 1255 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1256 if (New->getStorageClass() == VarDecl::Static && 1257 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1258 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1259 Diag(Old->getLocation(), diag::note_previous_definition); 1260 return New->setInvalidDecl(); 1261 } 1262 // C99 6.2.2p4: 1263 // For an identifier declared with the storage-class specifier 1264 // extern in a scope in which a prior declaration of that 1265 // identifier is visible,23) if the prior declaration specifies 1266 // internal or external linkage, the linkage of the identifier at 1267 // the later declaration is the same as the linkage specified at 1268 // the prior declaration. If no prior declaration is visible, or 1269 // if the prior declaration specifies no linkage, then the 1270 // identifier has external linkage. 1271 if (New->hasExternalStorage() && Old->hasLinkage()) 1272 /* Okay */; 1273 else if (New->getStorageClass() != VarDecl::Static && 1274 Old->getStorageClass() == VarDecl::Static) { 1275 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1276 Diag(Old->getLocation(), diag::note_previous_definition); 1277 return New->setInvalidDecl(); 1278 } 1279 1280 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1281 1282 // FIXME: The test for external storage here seems wrong? We still 1283 // need to check for mismatches. 1284 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1285 // Don't complain about out-of-line definitions of static members. 1286 !(Old->getLexicalDeclContext()->isRecord() && 1287 !New->getLexicalDeclContext()->isRecord())) { 1288 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1289 Diag(Old->getLocation(), diag::note_previous_definition); 1290 return New->setInvalidDecl(); 1291 } 1292 1293 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1294 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1295 Diag(Old->getLocation(), diag::note_previous_definition); 1296 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1297 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1298 Diag(Old->getLocation(), diag::note_previous_definition); 1299 } 1300 1301 // Keep a chain of previous declarations. 1302 New->setPreviousDeclaration(Old); 1303 1304 // Inherit access appropriately. 1305 New->setAccess(Old->getAccess()); 1306} 1307 1308/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1309/// no declarator (e.g. "struct foo;") is parsed. 1310Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1311 // FIXME: Error on auto/register at file scope 1312 // FIXME: Error on inline/virtual/explicit 1313 // FIXME: Warn on useless __thread 1314 // FIXME: Warn on useless const/volatile 1315 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1316 // FIXME: Warn on useless attributes 1317 Decl *TagD = 0; 1318 TagDecl *Tag = 0; 1319 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1320 DS.getTypeSpecType() == DeclSpec::TST_struct || 1321 DS.getTypeSpecType() == DeclSpec::TST_union || 1322 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1323 TagD = static_cast<Decl *>(DS.getTypeRep()); 1324 1325 if (!TagD) // We probably had an error 1326 return DeclPtrTy(); 1327 1328 // Note that the above type specs guarantee that the 1329 // type rep is a Decl, whereas in many of the others 1330 // it's a Type. 1331 Tag = dyn_cast<TagDecl>(TagD); 1332 } 1333 1334 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1335 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1336 // or incomplete types shall not be restrict-qualified." 1337 if (TypeQuals & DeclSpec::TQ_restrict) 1338 Diag(DS.getRestrictSpecLoc(), 1339 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1340 << DS.getSourceRange(); 1341 } 1342 1343 if (DS.isFriendSpecified()) { 1344 // If we're dealing with a class template decl, assume that the 1345 // template routines are handling it. 1346 if (TagD && isa<ClassTemplateDecl>(TagD)) 1347 return DeclPtrTy(); 1348 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1349 } 1350 1351 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1352 // If there are attributes in the DeclSpec, apply them to the record. 1353 if (const AttributeList *AL = DS.getAttributes()) 1354 ProcessDeclAttributeList(S, Record, AL); 1355 1356 if (!Record->getDeclName() && Record->isDefinition() && 1357 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1358 if (getLangOptions().CPlusPlus || 1359 Record->getDeclContext()->isRecord()) 1360 return BuildAnonymousStructOrUnion(S, DS, Record); 1361 1362 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1363 << DS.getSourceRange(); 1364 } 1365 1366 // Microsoft allows unnamed struct/union fields. Don't complain 1367 // about them. 1368 // FIXME: Should we support Microsoft's extensions in this area? 1369 if (Record->getDeclName() && getLangOptions().Microsoft) 1370 return DeclPtrTy::make(Tag); 1371 } 1372 1373 if (!DS.isMissingDeclaratorOk() && 1374 DS.getTypeSpecType() != DeclSpec::TST_error) { 1375 // Warn about typedefs of enums without names, since this is an 1376 // extension in both Microsoft an GNU. 1377 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1378 Tag && isa<EnumDecl>(Tag)) { 1379 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1380 << DS.getSourceRange(); 1381 return DeclPtrTy::make(Tag); 1382 } 1383 1384 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1385 << DS.getSourceRange(); 1386 return DeclPtrTy(); 1387 } 1388 1389 return DeclPtrTy::make(Tag); 1390} 1391 1392/// We are trying to inject an anonymous member into the given scope; 1393/// check if there's an existing declaration that can't be overloaded. 1394/// 1395/// \return true if this is a forbidden redeclaration 1396static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1397 Scope *S, 1398 DeclContext *Owner, 1399 DeclarationName Name, 1400 SourceLocation NameLoc, 1401 unsigned diagnostic) { 1402 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1403 Sema::ForRedeclaration); 1404 if (!SemaRef.LookupName(R, S)) return false; 1405 1406 if (R.getAsSingle<TagDecl>()) 1407 return false; 1408 1409 // Pick a representative declaration. 1410 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1411 if (PrevDecl && Owner->isRecord()) { 1412 RecordDecl *Record = cast<RecordDecl>(Owner); 1413 if (!SemaRef.isDeclInScope(PrevDecl, Record, S)) 1414 return false; 1415 } 1416 1417 SemaRef.Diag(NameLoc, diagnostic) << Name; 1418 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1419 1420 return true; 1421} 1422 1423/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1424/// anonymous struct or union AnonRecord into the owning context Owner 1425/// and scope S. This routine will be invoked just after we realize 1426/// that an unnamed union or struct is actually an anonymous union or 1427/// struct, e.g., 1428/// 1429/// @code 1430/// union { 1431/// int i; 1432/// float f; 1433/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1434/// // f into the surrounding scope.x 1435/// @endcode 1436/// 1437/// This routine is recursive, injecting the names of nested anonymous 1438/// structs/unions into the owning context and scope as well. 1439bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1440 RecordDecl *AnonRecord) { 1441 unsigned diagKind 1442 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1443 : diag::err_anonymous_struct_member_redecl; 1444 1445 bool Invalid = false; 1446 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1447 FEnd = AnonRecord->field_end(); 1448 F != FEnd; ++F) { 1449 if ((*F)->getDeclName()) { 1450 if (CheckAnonMemberRedeclaration(*this, S, Owner, (*F)->getDeclName(), 1451 (*F)->getLocation(), diagKind)) { 1452 // C++ [class.union]p2: 1453 // The names of the members of an anonymous union shall be 1454 // distinct from the names of any other entity in the 1455 // scope in which the anonymous union is declared. 1456 Invalid = true; 1457 } else { 1458 // C++ [class.union]p2: 1459 // For the purpose of name lookup, after the anonymous union 1460 // definition, the members of the anonymous union are 1461 // considered to have been defined in the scope in which the 1462 // anonymous union is declared. 1463 Owner->makeDeclVisibleInContext(*F); 1464 S->AddDecl(DeclPtrTy::make(*F)); 1465 IdResolver.AddDecl(*F); 1466 } 1467 } else if (const RecordType *InnerRecordType 1468 = (*F)->getType()->getAs<RecordType>()) { 1469 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1470 if (InnerRecord->isAnonymousStructOrUnion()) 1471 Invalid = Invalid || 1472 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1473 } 1474 } 1475 1476 return Invalid; 1477} 1478 1479/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1480/// anonymous structure or union. Anonymous unions are a C++ feature 1481/// (C++ [class.union]) and a GNU C extension; anonymous structures 1482/// are a GNU C and GNU C++ extension. 1483Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1484 RecordDecl *Record) { 1485 DeclContext *Owner = Record->getDeclContext(); 1486 1487 // Diagnose whether this anonymous struct/union is an extension. 1488 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1489 Diag(Record->getLocation(), diag::ext_anonymous_union); 1490 else if (!Record->isUnion()) 1491 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1492 1493 // C and C++ require different kinds of checks for anonymous 1494 // structs/unions. 1495 bool Invalid = false; 1496 if (getLangOptions().CPlusPlus) { 1497 const char* PrevSpec = 0; 1498 unsigned DiagID; 1499 // C++ [class.union]p3: 1500 // Anonymous unions declared in a named namespace or in the 1501 // global namespace shall be declared static. 1502 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1503 (isa<TranslationUnitDecl>(Owner) || 1504 (isa<NamespaceDecl>(Owner) && 1505 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1506 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1507 Invalid = true; 1508 1509 // Recover by adding 'static'. 1510 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1511 PrevSpec, DiagID); 1512 } 1513 // C++ [class.union]p3: 1514 // A storage class is not allowed in a declaration of an 1515 // anonymous union in a class scope. 1516 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1517 isa<RecordDecl>(Owner)) { 1518 Diag(DS.getStorageClassSpecLoc(), 1519 diag::err_anonymous_union_with_storage_spec); 1520 Invalid = true; 1521 1522 // Recover by removing the storage specifier. 1523 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1524 PrevSpec, DiagID); 1525 } 1526 1527 // C++ [class.union]p2: 1528 // The member-specification of an anonymous union shall only 1529 // define non-static data members. [Note: nested types and 1530 // functions cannot be declared within an anonymous union. ] 1531 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1532 MemEnd = Record->decls_end(); 1533 Mem != MemEnd; ++Mem) { 1534 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1535 // C++ [class.union]p3: 1536 // An anonymous union shall not have private or protected 1537 // members (clause 11). 1538 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1539 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1540 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1541 Invalid = true; 1542 } 1543 } else if ((*Mem)->isImplicit()) { 1544 // Any implicit members are fine. 1545 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1546 // This is a type that showed up in an 1547 // elaborated-type-specifier inside the anonymous struct or 1548 // union, but which actually declares a type outside of the 1549 // anonymous struct or union. It's okay. 1550 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1551 if (!MemRecord->isAnonymousStructOrUnion() && 1552 MemRecord->getDeclName()) { 1553 // This is a nested type declaration. 1554 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1555 << (int)Record->isUnion(); 1556 Invalid = true; 1557 } 1558 } else { 1559 // We have something that isn't a non-static data 1560 // member. Complain about it. 1561 unsigned DK = diag::err_anonymous_record_bad_member; 1562 if (isa<TypeDecl>(*Mem)) 1563 DK = diag::err_anonymous_record_with_type; 1564 else if (isa<FunctionDecl>(*Mem)) 1565 DK = diag::err_anonymous_record_with_function; 1566 else if (isa<VarDecl>(*Mem)) 1567 DK = diag::err_anonymous_record_with_static; 1568 Diag((*Mem)->getLocation(), DK) 1569 << (int)Record->isUnion(); 1570 Invalid = true; 1571 } 1572 } 1573 } 1574 1575 if (!Record->isUnion() && !Owner->isRecord()) { 1576 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1577 << (int)getLangOptions().CPlusPlus; 1578 Invalid = true; 1579 } 1580 1581 // Mock up a declarator. 1582 Declarator Dc(DS, Declarator::TypeNameContext); 1583 TypeSourceInfo *TInfo = 0; 1584 GetTypeForDeclarator(Dc, S, &TInfo); 1585 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1586 1587 // Create a declaration for this anonymous struct/union. 1588 NamedDecl *Anon = 0; 1589 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1590 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1591 /*IdentifierInfo=*/0, 1592 Context.getTypeDeclType(Record), 1593 TInfo, 1594 /*BitWidth=*/0, /*Mutable=*/false); 1595 Anon->setAccess(AS_public); 1596 if (getLangOptions().CPlusPlus) 1597 FieldCollector->Add(cast<FieldDecl>(Anon)); 1598 } else { 1599 VarDecl::StorageClass SC; 1600 switch (DS.getStorageClassSpec()) { 1601 default: assert(0 && "Unknown storage class!"); 1602 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1603 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1604 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1605 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1606 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1607 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1608 case DeclSpec::SCS_mutable: 1609 // mutable can only appear on non-static class members, so it's always 1610 // an error here 1611 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1612 Invalid = true; 1613 SC = VarDecl::None; 1614 break; 1615 } 1616 1617 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1618 /*IdentifierInfo=*/0, 1619 Context.getTypeDeclType(Record), 1620 TInfo, 1621 SC); 1622 } 1623 Anon->setImplicit(); 1624 1625 // Add the anonymous struct/union object to the current 1626 // context. We'll be referencing this object when we refer to one of 1627 // its members. 1628 Owner->addDecl(Anon); 1629 1630 // Inject the members of the anonymous struct/union into the owning 1631 // context and into the identifier resolver chain for name lookup 1632 // purposes. 1633 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1634 Invalid = true; 1635 1636 // Mark this as an anonymous struct/union type. Note that we do not 1637 // do this until after we have already checked and injected the 1638 // members of this anonymous struct/union type, because otherwise 1639 // the members could be injected twice: once by DeclContext when it 1640 // builds its lookup table, and once by 1641 // InjectAnonymousStructOrUnionMembers. 1642 Record->setAnonymousStructOrUnion(true); 1643 1644 if (Invalid) 1645 Anon->setInvalidDecl(); 1646 1647 return DeclPtrTy::make(Anon); 1648} 1649 1650 1651/// GetNameForDeclarator - Determine the full declaration name for the 1652/// given Declarator. 1653DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1654 return GetNameFromUnqualifiedId(D.getName()); 1655} 1656 1657/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1658DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1659 switch (Name.getKind()) { 1660 case UnqualifiedId::IK_Identifier: 1661 return DeclarationName(Name.Identifier); 1662 1663 case UnqualifiedId::IK_OperatorFunctionId: 1664 return Context.DeclarationNames.getCXXOperatorName( 1665 Name.OperatorFunctionId.Operator); 1666 1667 case UnqualifiedId::IK_LiteralOperatorId: 1668 return Context.DeclarationNames.getCXXLiteralOperatorName( 1669 Name.Identifier); 1670 1671 case UnqualifiedId::IK_ConversionFunctionId: { 1672 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1673 if (Ty.isNull()) 1674 return DeclarationName(); 1675 1676 return Context.DeclarationNames.getCXXConversionFunctionName( 1677 Context.getCanonicalType(Ty)); 1678 } 1679 1680 case UnqualifiedId::IK_ConstructorName: { 1681 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1682 if (Ty.isNull()) 1683 return DeclarationName(); 1684 1685 return Context.DeclarationNames.getCXXConstructorName( 1686 Context.getCanonicalType(Ty)); 1687 } 1688 1689 case UnqualifiedId::IK_ConstructorTemplateId: { 1690 // In well-formed code, we can only have a constructor 1691 // template-id that refers to the current context, so go there 1692 // to find the actual type being constructed. 1693 CXXRecordDecl *CurClass = dyn_cast<CXXRecordDecl>(CurContext); 1694 if (!CurClass || CurClass->getIdentifier() != Name.TemplateId->Name) 1695 return DeclarationName(); 1696 1697 // Determine the type of the class being constructed. 1698 QualType CurClassType; 1699 if (ClassTemplateDecl *ClassTemplate 1700 = CurClass->getDescribedClassTemplate()) 1701 CurClassType = ClassTemplate->getInjectedClassNameType(Context); 1702 else 1703 CurClassType = Context.getTypeDeclType(CurClass); 1704 1705 // FIXME: Check two things: that the template-id names the same type as 1706 // CurClassType, and that the template-id does not occur when the name 1707 // was qualified. 1708 1709 return Context.DeclarationNames.getCXXConstructorName( 1710 Context.getCanonicalType(CurClassType)); 1711 } 1712 1713 case UnqualifiedId::IK_DestructorName: { 1714 QualType Ty = GetTypeFromParser(Name.DestructorName); 1715 if (Ty.isNull()) 1716 return DeclarationName(); 1717 1718 return Context.DeclarationNames.getCXXDestructorName( 1719 Context.getCanonicalType(Ty)); 1720 } 1721 1722 case UnqualifiedId::IK_TemplateId: { 1723 TemplateName TName 1724 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1725 return Context.getNameForTemplate(TName); 1726 } 1727 } 1728 1729 assert(false && "Unknown name kind"); 1730 return DeclarationName(); 1731} 1732 1733/// isNearlyMatchingFunction - Determine whether the C++ functions 1734/// Declaration and Definition are "nearly" matching. This heuristic 1735/// is used to improve diagnostics in the case where an out-of-line 1736/// function definition doesn't match any declaration within 1737/// the class or namespace. 1738static bool isNearlyMatchingFunction(ASTContext &Context, 1739 FunctionDecl *Declaration, 1740 FunctionDecl *Definition) { 1741 if (Declaration->param_size() != Definition->param_size()) 1742 return false; 1743 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1744 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1745 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1746 1747 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1748 DefParamTy.getNonReferenceType())) 1749 return false; 1750 } 1751 1752 return true; 1753} 1754 1755Sema::DeclPtrTy 1756Sema::HandleDeclarator(Scope *S, Declarator &D, 1757 MultiTemplateParamsArg TemplateParamLists, 1758 bool IsFunctionDefinition) { 1759 DeclarationName Name = GetNameForDeclarator(D); 1760 1761 // All of these full declarators require an identifier. If it doesn't have 1762 // one, the ParsedFreeStandingDeclSpec action should be used. 1763 if (!Name) { 1764 if (!D.isInvalidType()) // Reject this if we think it is valid. 1765 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1766 diag::err_declarator_need_ident) 1767 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1768 return DeclPtrTy(); 1769 } 1770 1771 // The scope passed in may not be a decl scope. Zip up the scope tree until 1772 // we find one that is. 1773 while ((S->getFlags() & Scope::DeclScope) == 0 || 1774 (S->getFlags() & Scope::TemplateParamScope) != 0) 1775 S = S->getParent(); 1776 1777 // If this is an out-of-line definition of a member of a class template 1778 // or class template partial specialization, we may need to rebuild the 1779 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1780 // for more information. 1781 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1782 // handle expressions properly. 1783 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1784 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1785 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1786 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1787 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1788 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1789 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1790 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1791 // FIXME: Preserve type source info. 1792 QualType T = GetTypeFromParser(DS.getTypeRep()); 1793 1794 DeclContext *SavedContext = CurContext; 1795 CurContext = DC; 1796 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1797 CurContext = SavedContext; 1798 1799 if (T.isNull()) 1800 return DeclPtrTy(); 1801 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1802 } 1803 } 1804 1805 DeclContext *DC; 1806 NamedDecl *New; 1807 1808 TypeSourceInfo *TInfo = 0; 1809 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1810 1811 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1812 ForRedeclaration); 1813 1814 // See if this is a redefinition of a variable in the same scope. 1815 if (D.getCXXScopeSpec().isInvalid()) { 1816 DC = CurContext; 1817 D.setInvalidType(); 1818 } else if (!D.getCXXScopeSpec().isSet()) { 1819 bool IsLinkageLookup = false; 1820 1821 // If the declaration we're planning to build will be a function 1822 // or object with linkage, then look for another declaration with 1823 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1824 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1825 /* Do nothing*/; 1826 else if (R->isFunctionType()) { 1827 if (CurContext->isFunctionOrMethod() || 1828 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1829 IsLinkageLookup = true; 1830 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1831 IsLinkageLookup = true; 1832 else if (CurContext->getLookupContext()->isTranslationUnit() && 1833 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1834 IsLinkageLookup = true; 1835 1836 if (IsLinkageLookup) 1837 Previous.clear(LookupRedeclarationWithLinkage); 1838 1839 DC = CurContext; 1840 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1841 } else { // Something like "int foo::x;" 1842 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1843 1844 if (!DC) { 1845 // If we could not compute the declaration context, it's because the 1846 // declaration context is dependent but does not refer to a class, 1847 // class template, or class template partial specialization. Complain 1848 // and return early, to avoid the coming semantic disaster. 1849 Diag(D.getIdentifierLoc(), 1850 diag::err_template_qualified_declarator_no_match) 1851 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1852 << D.getCXXScopeSpec().getRange(); 1853 return DeclPtrTy(); 1854 } 1855 1856 if (!DC->isDependentContext() && 1857 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1858 return DeclPtrTy(); 1859 1860 LookupQualifiedName(Previous, DC); 1861 1862 // Don't consider using declarations as previous declarations for 1863 // out-of-line members. 1864 RemoveUsingDecls(Previous); 1865 1866 // C++ 7.3.1.2p2: 1867 // Members (including explicit specializations of templates) of a named 1868 // namespace can also be defined outside that namespace by explicit 1869 // qualification of the name being defined, provided that the entity being 1870 // defined was already declared in the namespace and the definition appears 1871 // after the point of declaration in a namespace that encloses the 1872 // declarations namespace. 1873 // 1874 // Note that we only check the context at this point. We don't yet 1875 // have enough information to make sure that PrevDecl is actually 1876 // the declaration we want to match. For example, given: 1877 // 1878 // class X { 1879 // void f(); 1880 // void f(float); 1881 // }; 1882 // 1883 // void X::f(int) { } // ill-formed 1884 // 1885 // In this case, PrevDecl will point to the overload set 1886 // containing the two f's declared in X, but neither of them 1887 // matches. 1888 1889 // First check whether we named the global scope. 1890 if (isa<TranslationUnitDecl>(DC)) { 1891 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1892 << Name << D.getCXXScopeSpec().getRange(); 1893 } else { 1894 DeclContext *Cur = CurContext; 1895 while (isa<LinkageSpecDecl>(Cur)) 1896 Cur = Cur->getParent(); 1897 if (!Cur->Encloses(DC)) { 1898 // The qualifying scope doesn't enclose the original declaration. 1899 // Emit diagnostic based on current scope. 1900 SourceLocation L = D.getIdentifierLoc(); 1901 SourceRange R = D.getCXXScopeSpec().getRange(); 1902 if (isa<FunctionDecl>(Cur)) 1903 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1904 else 1905 Diag(L, diag::err_invalid_declarator_scope) 1906 << Name << cast<NamedDecl>(DC) << R; 1907 D.setInvalidType(); 1908 } 1909 } 1910 } 1911 1912 if (Previous.isSingleResult() && 1913 Previous.getFoundDecl()->isTemplateParameter()) { 1914 // Maybe we will complain about the shadowed template parameter. 1915 if (!D.isInvalidType()) 1916 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 1917 Previous.getFoundDecl())) 1918 D.setInvalidType(); 1919 1920 // Just pretend that we didn't see the previous declaration. 1921 Previous.clear(); 1922 } 1923 1924 // In C++, the previous declaration we find might be a tag type 1925 // (class or enum). In this case, the new declaration will hide the 1926 // tag type. Note that this does does not apply if we're declaring a 1927 // typedef (C++ [dcl.typedef]p4). 1928 if (Previous.isSingleTagDecl() && 1929 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1930 Previous.clear(); 1931 1932 bool Redeclaration = false; 1933 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1934 if (TemplateParamLists.size()) { 1935 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1936 return DeclPtrTy(); 1937 } 1938 1939 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 1940 } else if (R->isFunctionType()) { 1941 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 1942 move(TemplateParamLists), 1943 IsFunctionDefinition, Redeclaration); 1944 } else { 1945 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 1946 move(TemplateParamLists), 1947 Redeclaration); 1948 } 1949 1950 if (New == 0) 1951 return DeclPtrTy(); 1952 1953 // If this has an identifier and is not an invalid redeclaration or 1954 // function template specialization, add it to the scope stack. 1955 if (Name && !(Redeclaration && New->isInvalidDecl())) 1956 PushOnScopeChains(New, S); 1957 1958 return DeclPtrTy::make(New); 1959} 1960 1961/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1962/// types into constant array types in certain situations which would otherwise 1963/// be errors (for GCC compatibility). 1964static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1965 ASTContext &Context, 1966 bool &SizeIsNegative) { 1967 // This method tries to turn a variable array into a constant 1968 // array even when the size isn't an ICE. This is necessary 1969 // for compatibility with code that depends on gcc's buggy 1970 // constant expression folding, like struct {char x[(int)(char*)2];} 1971 SizeIsNegative = false; 1972 1973 QualifierCollector Qs; 1974 const Type *Ty = Qs.strip(T); 1975 1976 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1977 QualType Pointee = PTy->getPointeeType(); 1978 QualType FixedType = 1979 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1980 if (FixedType.isNull()) return FixedType; 1981 FixedType = Context.getPointerType(FixedType); 1982 return Qs.apply(FixedType); 1983 } 1984 1985 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1986 if (!VLATy) 1987 return QualType(); 1988 // FIXME: We should probably handle this case 1989 if (VLATy->getElementType()->isVariablyModifiedType()) 1990 return QualType(); 1991 1992 Expr::EvalResult EvalResult; 1993 if (!VLATy->getSizeExpr() || 1994 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1995 !EvalResult.Val.isInt()) 1996 return QualType(); 1997 1998 llvm::APSInt &Res = EvalResult.Val.getInt(); 1999 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2000 // TODO: preserve the size expression in declarator info 2001 return Context.getConstantArrayType(VLATy->getElementType(), 2002 Res, ArrayType::Normal, 0); 2003 } 2004 2005 SizeIsNegative = true; 2006 return QualType(); 2007} 2008 2009/// \brief Register the given locally-scoped external C declaration so 2010/// that it can be found later for redeclarations 2011void 2012Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2013 const LookupResult &Previous, 2014 Scope *S) { 2015 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2016 "Decl is not a locally-scoped decl!"); 2017 // Note that we have a locally-scoped external with this name. 2018 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2019 2020 if (!Previous.isSingleResult()) 2021 return; 2022 2023 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2024 2025 // If there was a previous declaration of this variable, it may be 2026 // in our identifier chain. Update the identifier chain with the new 2027 // declaration. 2028 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2029 // The previous declaration was found on the identifer resolver 2030 // chain, so remove it from its scope. 2031 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2032 S = S->getParent(); 2033 2034 if (S) 2035 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2036 } 2037} 2038 2039/// \brief Diagnose function specifiers on a declaration of an identifier that 2040/// does not identify a function. 2041void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2042 // FIXME: We should probably indicate the identifier in question to avoid 2043 // confusion for constructs like "inline int a(), b;" 2044 if (D.getDeclSpec().isInlineSpecified()) 2045 Diag(D.getDeclSpec().getInlineSpecLoc(), 2046 diag::err_inline_non_function); 2047 2048 if (D.getDeclSpec().isVirtualSpecified()) 2049 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2050 diag::err_virtual_non_function); 2051 2052 if (D.getDeclSpec().isExplicitSpecified()) 2053 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2054 diag::err_explicit_non_function); 2055} 2056 2057NamedDecl* 2058Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2059 QualType R, TypeSourceInfo *TInfo, 2060 LookupResult &Previous, bool &Redeclaration) { 2061 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2062 if (D.getCXXScopeSpec().isSet()) { 2063 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2064 << D.getCXXScopeSpec().getRange(); 2065 D.setInvalidType(); 2066 // Pretend we didn't see the scope specifier. 2067 DC = 0; 2068 } 2069 2070 if (getLangOptions().CPlusPlus) { 2071 // Check that there are no default arguments (C++ only). 2072 CheckExtraCXXDefaultArguments(D); 2073 } 2074 2075 DiagnoseFunctionSpecifiers(D); 2076 2077 if (D.getDeclSpec().isThreadSpecified()) 2078 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2079 2080 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2081 if (!NewTD) return 0; 2082 2083 // Handle attributes prior to checking for duplicates in MergeVarDecl 2084 ProcessDeclAttributes(S, NewTD, D); 2085 2086 // Merge the decl with the existing one if appropriate. If the decl is 2087 // in an outer scope, it isn't the same thing. 2088 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2089 if (!Previous.empty()) { 2090 Redeclaration = true; 2091 MergeTypeDefDecl(NewTD, Previous); 2092 } 2093 2094 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2095 // then it shall have block scope. 2096 QualType T = NewTD->getUnderlyingType(); 2097 if (T->isVariablyModifiedType()) { 2098 CurFunctionNeedsScopeChecking = true; 2099 2100 if (S->getFnParent() == 0) { 2101 bool SizeIsNegative; 2102 QualType FixedTy = 2103 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2104 if (!FixedTy.isNull()) { 2105 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2106 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2107 } else { 2108 if (SizeIsNegative) 2109 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2110 else if (T->isVariableArrayType()) 2111 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2112 else 2113 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2114 NewTD->setInvalidDecl(); 2115 } 2116 } 2117 } 2118 2119 // If this is the C FILE type, notify the AST context. 2120 if (IdentifierInfo *II = NewTD->getIdentifier()) 2121 if (!NewTD->isInvalidDecl() && 2122 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2123 if (II->isStr("FILE")) 2124 Context.setFILEDecl(NewTD); 2125 else if (II->isStr("jmp_buf")) 2126 Context.setjmp_bufDecl(NewTD); 2127 else if (II->isStr("sigjmp_buf")) 2128 Context.setsigjmp_bufDecl(NewTD); 2129 } 2130 2131 return NewTD; 2132} 2133 2134/// \brief Determines whether the given declaration is an out-of-scope 2135/// previous declaration. 2136/// 2137/// This routine should be invoked when name lookup has found a 2138/// previous declaration (PrevDecl) that is not in the scope where a 2139/// new declaration by the same name is being introduced. If the new 2140/// declaration occurs in a local scope, previous declarations with 2141/// linkage may still be considered previous declarations (C99 2142/// 6.2.2p4-5, C++ [basic.link]p6). 2143/// 2144/// \param PrevDecl the previous declaration found by name 2145/// lookup 2146/// 2147/// \param DC the context in which the new declaration is being 2148/// declared. 2149/// 2150/// \returns true if PrevDecl is an out-of-scope previous declaration 2151/// for a new delcaration with the same name. 2152static bool 2153isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2154 ASTContext &Context) { 2155 if (!PrevDecl) 2156 return 0; 2157 2158 if (!PrevDecl->hasLinkage()) 2159 return false; 2160 2161 if (Context.getLangOptions().CPlusPlus) { 2162 // C++ [basic.link]p6: 2163 // If there is a visible declaration of an entity with linkage 2164 // having the same name and type, ignoring entities declared 2165 // outside the innermost enclosing namespace scope, the block 2166 // scope declaration declares that same entity and receives the 2167 // linkage of the previous declaration. 2168 DeclContext *OuterContext = DC->getLookupContext(); 2169 if (!OuterContext->isFunctionOrMethod()) 2170 // This rule only applies to block-scope declarations. 2171 return false; 2172 else { 2173 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2174 if (PrevOuterContext->isRecord()) 2175 // We found a member function: ignore it. 2176 return false; 2177 else { 2178 // Find the innermost enclosing namespace for the new and 2179 // previous declarations. 2180 while (!OuterContext->isFileContext()) 2181 OuterContext = OuterContext->getParent(); 2182 while (!PrevOuterContext->isFileContext()) 2183 PrevOuterContext = PrevOuterContext->getParent(); 2184 2185 // The previous declaration is in a different namespace, so it 2186 // isn't the same function. 2187 if (OuterContext->getPrimaryContext() != 2188 PrevOuterContext->getPrimaryContext()) 2189 return false; 2190 } 2191 } 2192 } 2193 2194 return true; 2195} 2196 2197NamedDecl* 2198Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2199 QualType R, TypeSourceInfo *TInfo, 2200 LookupResult &Previous, 2201 MultiTemplateParamsArg TemplateParamLists, 2202 bool &Redeclaration) { 2203 DeclarationName Name = GetNameForDeclarator(D); 2204 2205 // Check that there are no default arguments (C++ only). 2206 if (getLangOptions().CPlusPlus) 2207 CheckExtraCXXDefaultArguments(D); 2208 2209 VarDecl *NewVD; 2210 VarDecl::StorageClass SC; 2211 switch (D.getDeclSpec().getStorageClassSpec()) { 2212 default: assert(0 && "Unknown storage class!"); 2213 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2214 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2215 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2216 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2217 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2218 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2219 case DeclSpec::SCS_mutable: 2220 // mutable can only appear on non-static class members, so it's always 2221 // an error here 2222 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2223 D.setInvalidType(); 2224 SC = VarDecl::None; 2225 break; 2226 } 2227 2228 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2229 if (!II) { 2230 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2231 << Name.getAsString(); 2232 return 0; 2233 } 2234 2235 DiagnoseFunctionSpecifiers(D); 2236 2237 if (!DC->isRecord() && S->getFnParent() == 0) { 2238 // C99 6.9p2: The storage-class specifiers auto and register shall not 2239 // appear in the declaration specifiers in an external declaration. 2240 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2241 2242 // If this is a register variable with an asm label specified, then this 2243 // is a GNU extension. 2244 if (SC == VarDecl::Register && D.getAsmLabel()) 2245 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2246 else 2247 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2248 D.setInvalidType(); 2249 } 2250 } 2251 if (DC->isRecord() && !CurContext->isRecord()) { 2252 // This is an out-of-line definition of a static data member. 2253 if (SC == VarDecl::Static) { 2254 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2255 diag::err_static_out_of_line) 2256 << CodeModificationHint::CreateRemoval( 2257 D.getDeclSpec().getStorageClassSpecLoc()); 2258 } else if (SC == VarDecl::None) 2259 SC = VarDecl::Static; 2260 } 2261 if (SC == VarDecl::Static) { 2262 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2263 if (RD->isLocalClass()) 2264 Diag(D.getIdentifierLoc(), 2265 diag::err_static_data_member_not_allowed_in_local_class) 2266 << Name << RD->getDeclName(); 2267 } 2268 } 2269 2270 // Match up the template parameter lists with the scope specifier, then 2271 // determine whether we have a template or a template specialization. 2272 bool isExplicitSpecialization = false; 2273 if (TemplateParameterList *TemplateParams 2274 = MatchTemplateParametersToScopeSpecifier( 2275 D.getDeclSpec().getSourceRange().getBegin(), 2276 D.getCXXScopeSpec(), 2277 (TemplateParameterList**)TemplateParamLists.get(), 2278 TemplateParamLists.size(), 2279 isExplicitSpecialization)) { 2280 if (TemplateParams->size() > 0) { 2281 // There is no such thing as a variable template. 2282 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2283 << II 2284 << SourceRange(TemplateParams->getTemplateLoc(), 2285 TemplateParams->getRAngleLoc()); 2286 return 0; 2287 } else { 2288 // There is an extraneous 'template<>' for this variable. Complain 2289 // about it, but allow the declaration of the variable. 2290 Diag(TemplateParams->getTemplateLoc(), 2291 diag::err_template_variable_noparams) 2292 << II 2293 << SourceRange(TemplateParams->getTemplateLoc(), 2294 TemplateParams->getRAngleLoc()); 2295 2296 isExplicitSpecialization = true; 2297 } 2298 } 2299 2300 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2301 II, R, TInfo, SC); 2302 2303 if (D.isInvalidType()) 2304 NewVD->setInvalidDecl(); 2305 2306 if (D.getDeclSpec().isThreadSpecified()) { 2307 if (NewVD->hasLocalStorage()) 2308 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2309 else if (!Context.Target.isTLSSupported()) 2310 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2311 else 2312 NewVD->setThreadSpecified(true); 2313 } 2314 2315 // Set the lexical context. If the declarator has a C++ scope specifier, the 2316 // lexical context will be different from the semantic context. 2317 NewVD->setLexicalDeclContext(CurContext); 2318 2319 // Handle attributes prior to checking for duplicates in MergeVarDecl 2320 ProcessDeclAttributes(S, NewVD, D); 2321 2322 // Handle GNU asm-label extension (encoded as an attribute). 2323 if (Expr *E = (Expr*) D.getAsmLabel()) { 2324 // The parser guarantees this is a string. 2325 StringLiteral *SE = cast<StringLiteral>(E); 2326 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2327 } 2328 2329 // Don't consider existing declarations that are in a different 2330 // scope and are out-of-semantic-context declarations (if the new 2331 // declaration has linkage). 2332 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2333 2334 // Merge the decl with the existing one if appropriate. 2335 if (!Previous.empty()) { 2336 if (Previous.isSingleResult() && 2337 isa<FieldDecl>(Previous.getFoundDecl()) && 2338 D.getCXXScopeSpec().isSet()) { 2339 // The user tried to define a non-static data member 2340 // out-of-line (C++ [dcl.meaning]p1). 2341 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2342 << D.getCXXScopeSpec().getRange(); 2343 Previous.clear(); 2344 NewVD->setInvalidDecl(); 2345 } 2346 } else if (D.getCXXScopeSpec().isSet()) { 2347 // No previous declaration in the qualifying scope. 2348 Diag(D.getIdentifierLoc(), diag::err_no_member) 2349 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2350 << D.getCXXScopeSpec().getRange(); 2351 NewVD->setInvalidDecl(); 2352 } 2353 2354 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2355 2356 // This is an explicit specialization of a static data member. Check it. 2357 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2358 CheckMemberSpecialization(NewVD, Previous)) 2359 NewVD->setInvalidDecl(); 2360 2361 // attributes declared post-definition are currently ignored 2362 if (Previous.isSingleResult()) { 2363 const VarDecl *Def = 0; 2364 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2365 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2366 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2367 Diag(Def->getLocation(), diag::note_previous_definition); 2368 } 2369 } 2370 2371 // If this is a locally-scoped extern C variable, update the map of 2372 // such variables. 2373 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2374 !NewVD->isInvalidDecl()) 2375 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2376 2377 return NewVD; 2378} 2379 2380/// \brief Perform semantic checking on a newly-created variable 2381/// declaration. 2382/// 2383/// This routine performs all of the type-checking required for a 2384/// variable declaration once it has been built. It is used both to 2385/// check variables after they have been parsed and their declarators 2386/// have been translated into a declaration, and to check variables 2387/// that have been instantiated from a template. 2388/// 2389/// Sets NewVD->isInvalidDecl() if an error was encountered. 2390void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2391 LookupResult &Previous, 2392 bool &Redeclaration) { 2393 // If the decl is already known invalid, don't check it. 2394 if (NewVD->isInvalidDecl()) 2395 return; 2396 2397 QualType T = NewVD->getType(); 2398 2399 if (T->isObjCInterfaceType()) { 2400 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2401 return NewVD->setInvalidDecl(); 2402 } 2403 2404 // Emit an error if an address space was applied to decl with local storage. 2405 // This includes arrays of objects with address space qualifiers, but not 2406 // automatic variables that point to other address spaces. 2407 // ISO/IEC TR 18037 S5.1.2 2408 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2409 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2410 return NewVD->setInvalidDecl(); 2411 } 2412 2413 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2414 && !NewVD->hasAttr<BlocksAttr>()) 2415 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2416 2417 bool isVM = T->isVariablyModifiedType(); 2418 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2419 NewVD->hasAttr<BlocksAttr>()) 2420 CurFunctionNeedsScopeChecking = true; 2421 2422 if ((isVM && NewVD->hasLinkage()) || 2423 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2424 bool SizeIsNegative; 2425 QualType FixedTy = 2426 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2427 2428 if (FixedTy.isNull() && T->isVariableArrayType()) { 2429 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2430 // FIXME: This won't give the correct result for 2431 // int a[10][n]; 2432 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2433 2434 if (NewVD->isFileVarDecl()) 2435 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2436 << SizeRange; 2437 else if (NewVD->getStorageClass() == VarDecl::Static) 2438 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2439 << SizeRange; 2440 else 2441 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2442 << SizeRange; 2443 return NewVD->setInvalidDecl(); 2444 } 2445 2446 if (FixedTy.isNull()) { 2447 if (NewVD->isFileVarDecl()) 2448 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2449 else 2450 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2451 return NewVD->setInvalidDecl(); 2452 } 2453 2454 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2455 NewVD->setType(FixedTy); 2456 } 2457 2458 if (Previous.empty() && NewVD->isExternC()) { 2459 // Since we did not find anything by this name and we're declaring 2460 // an extern "C" variable, look for a non-visible extern "C" 2461 // declaration with the same name. 2462 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2463 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2464 if (Pos != LocallyScopedExternalDecls.end()) 2465 Previous.addDecl(Pos->second); 2466 } 2467 2468 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2469 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2470 << T; 2471 return NewVD->setInvalidDecl(); 2472 } 2473 2474 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2475 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2476 return NewVD->setInvalidDecl(); 2477 } 2478 2479 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2480 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2481 return NewVD->setInvalidDecl(); 2482 } 2483 2484 if (!Previous.empty()) { 2485 Redeclaration = true; 2486 MergeVarDecl(NewVD, Previous); 2487 } 2488} 2489 2490/// \brief Data used with FindOverriddenMethod 2491struct FindOverriddenMethodData { 2492 Sema *S; 2493 CXXMethodDecl *Method; 2494}; 2495 2496/// \brief Member lookup function that determines whether a given C++ 2497/// method overrides a method in a base class, to be used with 2498/// CXXRecordDecl::lookupInBases(). 2499static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2500 CXXBasePath &Path, 2501 void *UserData) { 2502 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2503 2504 FindOverriddenMethodData *Data 2505 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2506 2507 DeclarationName Name = Data->Method->getDeclName(); 2508 2509 // FIXME: Do we care about other names here too? 2510 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2511 // We really want to find the base class constructor here. 2512 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2513 CanQualType CT = Data->S->Context.getCanonicalType(T); 2514 2515 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2516 } 2517 2518 for (Path.Decls = BaseRecord->lookup(Name); 2519 Path.Decls.first != Path.Decls.second; 2520 ++Path.Decls.first) { 2521 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2522 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2523 return true; 2524 } 2525 } 2526 2527 return false; 2528} 2529 2530/// AddOverriddenMethods - See if a method overrides any in the base classes, 2531/// and if so, check that it's a valid override and remember it. 2532void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2533 // Look for virtual methods in base classes that this method might override. 2534 CXXBasePaths Paths; 2535 FindOverriddenMethodData Data; 2536 Data.Method = MD; 2537 Data.S = this; 2538 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2539 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2540 E = Paths.found_decls_end(); I != E; ++I) { 2541 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2542 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2543 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2544 !CheckOverridingFunctionAttributes(MD, OldMD)) 2545 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2546 } 2547 } 2548 } 2549} 2550 2551NamedDecl* 2552Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2553 QualType R, TypeSourceInfo *TInfo, 2554 LookupResult &Previous, 2555 MultiTemplateParamsArg TemplateParamLists, 2556 bool IsFunctionDefinition, bool &Redeclaration) { 2557 assert(R.getTypePtr()->isFunctionType()); 2558 2559 DeclarationName Name = GetNameForDeclarator(D); 2560 FunctionDecl::StorageClass SC = FunctionDecl::None; 2561 switch (D.getDeclSpec().getStorageClassSpec()) { 2562 default: assert(0 && "Unknown storage class!"); 2563 case DeclSpec::SCS_auto: 2564 case DeclSpec::SCS_register: 2565 case DeclSpec::SCS_mutable: 2566 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2567 diag::err_typecheck_sclass_func); 2568 D.setInvalidType(); 2569 break; 2570 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2571 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2572 case DeclSpec::SCS_static: { 2573 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2574 // C99 6.7.1p5: 2575 // The declaration of an identifier for a function that has 2576 // block scope shall have no explicit storage-class specifier 2577 // other than extern 2578 // See also (C++ [dcl.stc]p4). 2579 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2580 diag::err_static_block_func); 2581 SC = FunctionDecl::None; 2582 } else 2583 SC = FunctionDecl::Static; 2584 break; 2585 } 2586 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2587 } 2588 2589 if (D.getDeclSpec().isThreadSpecified()) 2590 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2591 2592 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2593 bool isInline = D.getDeclSpec().isInlineSpecified(); 2594 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2595 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2596 2597 // Check that the return type is not an abstract class type. 2598 // For record types, this is done by the AbstractClassUsageDiagnoser once 2599 // the class has been completely parsed. 2600 if (!DC->isRecord() && 2601 RequireNonAbstractType(D.getIdentifierLoc(), 2602 R->getAs<FunctionType>()->getResultType(), 2603 diag::err_abstract_type_in_decl, 2604 AbstractReturnType)) 2605 D.setInvalidType(); 2606 2607 // Do not allow returning a objc interface by-value. 2608 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2609 Diag(D.getIdentifierLoc(), 2610 diag::err_object_cannot_be_passed_returned_by_value) << 0 2611 << R->getAs<FunctionType>()->getResultType(); 2612 D.setInvalidType(); 2613 } 2614 2615 bool isVirtualOkay = false; 2616 FunctionDecl *NewFD; 2617 2618 if (isFriend) { 2619 // C++ [class.friend]p5 2620 // A function can be defined in a friend declaration of a 2621 // class . . . . Such a function is implicitly inline. 2622 isInline |= IsFunctionDefinition; 2623 } 2624 2625 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2626 // This is a C++ constructor declaration. 2627 assert(DC->isRecord() && 2628 "Constructors can only be declared in a member context"); 2629 2630 R = CheckConstructorDeclarator(D, R, SC); 2631 2632 // Create the new declaration 2633 NewFD = CXXConstructorDecl::Create(Context, 2634 cast<CXXRecordDecl>(DC), 2635 D.getIdentifierLoc(), Name, R, TInfo, 2636 isExplicit, isInline, 2637 /*isImplicitlyDeclared=*/false); 2638 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2639 // This is a C++ destructor declaration. 2640 if (DC->isRecord()) { 2641 R = CheckDestructorDeclarator(D, SC); 2642 2643 NewFD = CXXDestructorDecl::Create(Context, 2644 cast<CXXRecordDecl>(DC), 2645 D.getIdentifierLoc(), Name, R, 2646 isInline, 2647 /*isImplicitlyDeclared=*/false); 2648 2649 isVirtualOkay = true; 2650 } else { 2651 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2652 2653 // Create a FunctionDecl to satisfy the function definition parsing 2654 // code path. 2655 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2656 Name, R, TInfo, SC, isInline, 2657 /*hasPrototype=*/true); 2658 D.setInvalidType(); 2659 } 2660 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2661 if (!DC->isRecord()) { 2662 Diag(D.getIdentifierLoc(), 2663 diag::err_conv_function_not_member); 2664 return 0; 2665 } 2666 2667 CheckConversionDeclarator(D, R, SC); 2668 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2669 D.getIdentifierLoc(), Name, R, TInfo, 2670 isInline, isExplicit); 2671 2672 isVirtualOkay = true; 2673 } else if (DC->isRecord()) { 2674 // If the of the function is the same as the name of the record, then this 2675 // must be an invalid constructor that has a return type. 2676 // (The parser checks for a return type and makes the declarator a 2677 // constructor if it has no return type). 2678 // must have an invalid constructor that has a return type 2679 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2680 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2681 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2682 << SourceRange(D.getIdentifierLoc()); 2683 return 0; 2684 } 2685 2686 bool isStatic = SC == FunctionDecl::Static; 2687 2688 // [class.free]p1: 2689 // Any allocation function for a class T is a static member 2690 // (even if not explicitly declared static). 2691 if (Name.getCXXOverloadedOperator() == OO_New || 2692 Name.getCXXOverloadedOperator() == OO_Array_New) 2693 isStatic = true; 2694 2695 // [class.free]p6 Any deallocation function for a class X is a static member 2696 // (even if not explicitly declared static). 2697 if (Name.getCXXOverloadedOperator() == OO_Delete || 2698 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2699 isStatic = true; 2700 2701 // This is a C++ method declaration. 2702 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2703 D.getIdentifierLoc(), Name, R, TInfo, 2704 isStatic, isInline); 2705 2706 isVirtualOkay = !isStatic; 2707 } else { 2708 // Determine whether the function was written with a 2709 // prototype. This true when: 2710 // - we're in C++ (where every function has a prototype), 2711 // - there is a prototype in the declarator, or 2712 // - the type R of the function is some kind of typedef or other reference 2713 // to a type name (which eventually refers to a function type). 2714 bool HasPrototype = 2715 getLangOptions().CPlusPlus || 2716 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2717 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2718 2719 NewFD = FunctionDecl::Create(Context, DC, 2720 D.getIdentifierLoc(), 2721 Name, R, TInfo, SC, isInline, HasPrototype); 2722 } 2723 2724 if (D.isInvalidType()) 2725 NewFD->setInvalidDecl(); 2726 2727 // Set the lexical context. If the declarator has a C++ 2728 // scope specifier, or is the object of a friend declaration, the 2729 // lexical context will be different from the semantic context. 2730 NewFD->setLexicalDeclContext(CurContext); 2731 2732 // Match up the template parameter lists with the scope specifier, then 2733 // determine whether we have a template or a template specialization. 2734 FunctionTemplateDecl *FunctionTemplate = 0; 2735 bool isExplicitSpecialization = false; 2736 bool isFunctionTemplateSpecialization = false; 2737 if (TemplateParameterList *TemplateParams 2738 = MatchTemplateParametersToScopeSpecifier( 2739 D.getDeclSpec().getSourceRange().getBegin(), 2740 D.getCXXScopeSpec(), 2741 (TemplateParameterList**)TemplateParamLists.get(), 2742 TemplateParamLists.size(), 2743 isExplicitSpecialization)) { 2744 if (TemplateParams->size() > 0) { 2745 // This is a function template 2746 2747 // Check that we can declare a template here. 2748 if (CheckTemplateDeclScope(S, TemplateParams)) 2749 return 0; 2750 2751 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2752 NewFD->getLocation(), 2753 Name, TemplateParams, 2754 NewFD); 2755 FunctionTemplate->setLexicalDeclContext(CurContext); 2756 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2757 } else { 2758 // This is a function template specialization. 2759 isFunctionTemplateSpecialization = true; 2760 } 2761 2762 // FIXME: Free this memory properly. 2763 TemplateParamLists.release(); 2764 } 2765 2766 // C++ [dcl.fct.spec]p5: 2767 // The virtual specifier shall only be used in declarations of 2768 // nonstatic class member functions that appear within a 2769 // member-specification of a class declaration; see 10.3. 2770 // 2771 if (isVirtual && !NewFD->isInvalidDecl()) { 2772 if (!isVirtualOkay) { 2773 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2774 diag::err_virtual_non_function); 2775 } else if (!CurContext->isRecord()) { 2776 // 'virtual' was specified outside of the class. 2777 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2778 << CodeModificationHint::CreateRemoval( 2779 D.getDeclSpec().getVirtualSpecLoc()); 2780 } else { 2781 // Okay: Add virtual to the method. 2782 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2783 CurClass->setMethodAsVirtual(NewFD); 2784 } 2785 } 2786 2787 // C++ [dcl.fct.spec]p6: 2788 // The explicit specifier shall be used only in the declaration of a 2789 // constructor or conversion function within its class definition; see 12.3.1 2790 // and 12.3.2. 2791 if (isExplicit && !NewFD->isInvalidDecl()) { 2792 if (!CurContext->isRecord()) { 2793 // 'explicit' was specified outside of the class. 2794 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2795 diag::err_explicit_out_of_class) 2796 << CodeModificationHint::CreateRemoval( 2797 D.getDeclSpec().getExplicitSpecLoc()); 2798 } else if (!isa<CXXConstructorDecl>(NewFD) && 2799 !isa<CXXConversionDecl>(NewFD)) { 2800 // 'explicit' was specified on a function that wasn't a constructor 2801 // or conversion function. 2802 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2803 diag::err_explicit_non_ctor_or_conv_function) 2804 << CodeModificationHint::CreateRemoval( 2805 D.getDeclSpec().getExplicitSpecLoc()); 2806 } 2807 } 2808 2809 // Filter out previous declarations that don't match the scope. 2810 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2811 2812 if (isFriend) { 2813 // DC is the namespace in which the function is being declared. 2814 assert((DC->isFileContext() || !Previous.empty()) && 2815 "previously-undeclared friend function being created " 2816 "in a non-namespace context"); 2817 2818 if (FunctionTemplate) { 2819 FunctionTemplate->setObjectOfFriendDecl( 2820 /* PreviouslyDeclared= */ !Previous.empty()); 2821 FunctionTemplate->setAccess(AS_public); 2822 } 2823 else 2824 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2825 2826 NewFD->setAccess(AS_public); 2827 } 2828 2829 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2830 !CurContext->isRecord()) { 2831 // C++ [class.static]p1: 2832 // A data or function member of a class may be declared static 2833 // in a class definition, in which case it is a static member of 2834 // the class. 2835 2836 // Complain about the 'static' specifier if it's on an out-of-line 2837 // member function definition. 2838 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2839 diag::err_static_out_of_line) 2840 << CodeModificationHint::CreateRemoval( 2841 D.getDeclSpec().getStorageClassSpecLoc()); 2842 } 2843 2844 // Handle GNU asm-label extension (encoded as an attribute). 2845 if (Expr *E = (Expr*) D.getAsmLabel()) { 2846 // The parser guarantees this is a string. 2847 StringLiteral *SE = cast<StringLiteral>(E); 2848 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2849 } 2850 2851 // Copy the parameter declarations from the declarator D to the function 2852 // declaration NewFD, if they are available. First scavenge them into Params. 2853 llvm::SmallVector<ParmVarDecl*, 16> Params; 2854 if (D.getNumTypeObjects() > 0) { 2855 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2856 2857 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2858 // function that takes no arguments, not a function that takes a 2859 // single void argument. 2860 // We let through "const void" here because Sema::GetTypeForDeclarator 2861 // already checks for that case. 2862 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2863 FTI.ArgInfo[0].Param && 2864 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2865 // Empty arg list, don't push any params. 2866 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2867 2868 // In C++, the empty parameter-type-list must be spelled "void"; a 2869 // typedef of void is not permitted. 2870 if (getLangOptions().CPlusPlus && 2871 Param->getType().getUnqualifiedType() != Context.VoidTy) 2872 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2873 // FIXME: Leaks decl? 2874 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2875 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2876 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2877 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2878 Param->setDeclContext(NewFD); 2879 Params.push_back(Param); 2880 } 2881 } 2882 2883 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2884 // When we're declaring a function with a typedef, typeof, etc as in the 2885 // following example, we'll need to synthesize (unnamed) 2886 // parameters for use in the declaration. 2887 // 2888 // @code 2889 // typedef void fn(int); 2890 // fn f; 2891 // @endcode 2892 2893 // Synthesize a parameter for each argument type. 2894 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2895 AE = FT->arg_type_end(); AI != AE; ++AI) { 2896 ParmVarDecl *Param = ParmVarDecl::Create(Context, NewFD, 2897 SourceLocation(), 0, 2898 *AI, /*TInfo=*/0, 2899 VarDecl::None, 0); 2900 Param->setImplicit(); 2901 Params.push_back(Param); 2902 } 2903 } else { 2904 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2905 "Should not need args for typedef of non-prototype fn"); 2906 } 2907 // Finally, we know we have the right number of parameters, install them. 2908 NewFD->setParams(Context, Params.data(), Params.size()); 2909 2910 // If the declarator is a template-id, translate the parser's template 2911 // argument list into our AST format. 2912 bool HasExplicitTemplateArgs = false; 2913 TemplateArgumentListInfo TemplateArgs; 2914 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2915 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2916 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 2917 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 2918 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2919 TemplateId->getTemplateArgs(), 2920 TemplateId->NumArgs); 2921 translateTemplateArguments(TemplateArgsPtr, 2922 TemplateArgs); 2923 TemplateArgsPtr.release(); 2924 2925 HasExplicitTemplateArgs = true; 2926 2927 if (FunctionTemplate) { 2928 // FIXME: Diagnose function template with explicit template 2929 // arguments. 2930 HasExplicitTemplateArgs = false; 2931 } else if (!isFunctionTemplateSpecialization && 2932 !D.getDeclSpec().isFriendSpecified()) { 2933 // We have encountered something that the user meant to be a 2934 // specialization (because it has explicitly-specified template 2935 // arguments) but that was not introduced with a "template<>" (or had 2936 // too few of them). 2937 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2938 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2939 << CodeModificationHint::CreateInsertion( 2940 D.getDeclSpec().getSourceRange().getBegin(), 2941 "template<> "); 2942 isFunctionTemplateSpecialization = true; 2943 } 2944 } 2945 2946 if (isFunctionTemplateSpecialization) { 2947 if (CheckFunctionTemplateSpecialization(NewFD, 2948 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 2949 Previous)) 2950 NewFD->setInvalidDecl(); 2951 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2952 CheckMemberSpecialization(NewFD, Previous)) 2953 NewFD->setInvalidDecl(); 2954 2955 // Perform semantic checking on the function declaration. 2956 bool OverloadableAttrRequired = false; // FIXME: HACK! 2957 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 2958 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2959 2960 assert((NewFD->isInvalidDecl() || !Redeclaration || 2961 Previous.getResultKind() != LookupResult::FoundOverloaded) && 2962 "previous declaration set still overloaded"); 2963 2964 // If we have a function template, check the template parameter 2965 // list. This will check and merge default template arguments. 2966 if (FunctionTemplate) { 2967 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 2968 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 2969 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 2970 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 2971 : TPC_FunctionTemplate); 2972 } 2973 2974 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2975 // Fake up an access specifier if it's supposed to be a class member. 2976 if (isa<CXXRecordDecl>(NewFD->getDeclContext())) 2977 NewFD->setAccess(AS_public); 2978 2979 // An out-of-line member function declaration must also be a 2980 // definition (C++ [dcl.meaning]p1). 2981 // Note that this is not the case for explicit specializations of 2982 // function templates or member functions of class templates, per 2983 // C++ [temp.expl.spec]p2. 2984 if (!IsFunctionDefinition && !isFriend && 2985 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2986 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2987 << D.getCXXScopeSpec().getRange(); 2988 NewFD->setInvalidDecl(); 2989 } else if (!Redeclaration && 2990 !(isFriend && CurContext->isDependentContext())) { 2991 // The user tried to provide an out-of-line definition for a 2992 // function that is a member of a class or namespace, but there 2993 // was no such member function declared (C++ [class.mfct]p2, 2994 // C++ [namespace.memdef]p2). For example: 2995 // 2996 // class X { 2997 // void f() const; 2998 // }; 2999 // 3000 // void X::f() { } // ill-formed 3001 // 3002 // Complain about this problem, and attempt to suggest close 3003 // matches (e.g., those that differ only in cv-qualifiers and 3004 // whether the parameter types are references). 3005 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3006 << Name << DC << D.getCXXScopeSpec().getRange(); 3007 NewFD->setInvalidDecl(); 3008 3009 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3010 ForRedeclaration); 3011 LookupQualifiedName(Prev, DC); 3012 assert(!Prev.isAmbiguous() && 3013 "Cannot have an ambiguity in previous-declaration lookup"); 3014 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3015 Func != FuncEnd; ++Func) { 3016 if (isa<FunctionDecl>(*Func) && 3017 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3018 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3019 } 3020 } 3021 } 3022 3023 // Handle attributes. We need to have merged decls when handling attributes 3024 // (for example to check for conflicts, etc). 3025 // FIXME: This needs to happen before we merge declarations. Then, 3026 // let attribute merging cope with attribute conflicts. 3027 ProcessDeclAttributes(S, NewFD, D); 3028 3029 // attributes declared post-definition are currently ignored 3030 if (Redeclaration && Previous.isSingleResult()) { 3031 const FunctionDecl *Def; 3032 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3033 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3034 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3035 Diag(Def->getLocation(), diag::note_previous_definition); 3036 } 3037 } 3038 3039 AddKnownFunctionAttributes(NewFD); 3040 3041 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3042 // If a function name is overloadable in C, then every function 3043 // with that name must be marked "overloadable". 3044 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3045 << Redeclaration << NewFD; 3046 if (!Previous.empty()) 3047 Diag(Previous.getRepresentativeDecl()->getLocation(), 3048 diag::note_attribute_overloadable_prev_overload); 3049 NewFD->addAttr(::new (Context) OverloadableAttr()); 3050 } 3051 3052 // If this is a locally-scoped extern C function, update the 3053 // map of such names. 3054 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3055 && !NewFD->isInvalidDecl()) 3056 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3057 3058 // Set this FunctionDecl's range up to the right paren. 3059 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3060 3061 if (FunctionTemplate && NewFD->isInvalidDecl()) 3062 FunctionTemplate->setInvalidDecl(); 3063 3064 if (FunctionTemplate) 3065 return FunctionTemplate; 3066 3067 return NewFD; 3068} 3069 3070/// \brief Perform semantic checking of a new function declaration. 3071/// 3072/// Performs semantic analysis of the new function declaration 3073/// NewFD. This routine performs all semantic checking that does not 3074/// require the actual declarator involved in the declaration, and is 3075/// used both for the declaration of functions as they are parsed 3076/// (called via ActOnDeclarator) and for the declaration of functions 3077/// that have been instantiated via C++ template instantiation (called 3078/// via InstantiateDecl). 3079/// 3080/// \param IsExplicitSpecialiation whether this new function declaration is 3081/// an explicit specialization of the previous declaration. 3082/// 3083/// This sets NewFD->isInvalidDecl() to true if there was an error. 3084void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3085 LookupResult &Previous, 3086 bool IsExplicitSpecialization, 3087 bool &Redeclaration, 3088 bool &OverloadableAttrRequired) { 3089 // If NewFD is already known erroneous, don't do any of this checking. 3090 if (NewFD->isInvalidDecl()) 3091 return; 3092 3093 if (NewFD->getResultType()->isVariablyModifiedType()) { 3094 // Functions returning a variably modified type violate C99 6.7.5.2p2 3095 // because all functions have linkage. 3096 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3097 return NewFD->setInvalidDecl(); 3098 } 3099 3100 if (NewFD->isMain()) 3101 CheckMain(NewFD); 3102 3103 // Check for a previous declaration of this name. 3104 if (Previous.empty() && NewFD->isExternC()) { 3105 // Since we did not find anything by this name and we're declaring 3106 // an extern "C" function, look for a non-visible extern "C" 3107 // declaration with the same name. 3108 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3109 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3110 if (Pos != LocallyScopedExternalDecls.end()) 3111 Previous.addDecl(Pos->second); 3112 } 3113 3114 // Merge or overload the declaration with an existing declaration of 3115 // the same name, if appropriate. 3116 if (!Previous.empty()) { 3117 // Determine whether NewFD is an overload of PrevDecl or 3118 // a declaration that requires merging. If it's an overload, 3119 // there's no more work to do here; we'll just add the new 3120 // function to the scope. 3121 3122 NamedDecl *OldDecl = 0; 3123 if (!AllowOverloadingOfFunction(Previous, Context)) { 3124 Redeclaration = true; 3125 OldDecl = Previous.getFoundDecl(); 3126 } else { 3127 if (!getLangOptions().CPlusPlus) { 3128 OverloadableAttrRequired = true; 3129 3130 // Functions marked "overloadable" must have a prototype (that 3131 // we can't get through declaration merging). 3132 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3133 Diag(NewFD->getLocation(), 3134 diag::err_attribute_overloadable_no_prototype) 3135 << NewFD; 3136 Redeclaration = true; 3137 3138 // Turn this into a variadic function with no parameters. 3139 QualType R = Context.getFunctionType( 3140 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3141 0, 0, true, 0); 3142 NewFD->setType(R); 3143 return NewFD->setInvalidDecl(); 3144 } 3145 } 3146 3147 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3148 case Ovl_Match: 3149 Redeclaration = true; 3150 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3151 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3152 Redeclaration = false; 3153 } 3154 break; 3155 3156 case Ovl_NonFunction: 3157 Redeclaration = true; 3158 break; 3159 3160 case Ovl_Overload: 3161 Redeclaration = false; 3162 break; 3163 } 3164 } 3165 3166 if (Redeclaration) { 3167 // NewFD and OldDecl represent declarations that need to be 3168 // merged. 3169 if (MergeFunctionDecl(NewFD, OldDecl)) 3170 return NewFD->setInvalidDecl(); 3171 3172 Previous.clear(); 3173 Previous.addDecl(OldDecl); 3174 3175 if (FunctionTemplateDecl *OldTemplateDecl 3176 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3177 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3178 FunctionTemplateDecl *NewTemplateDecl 3179 = NewFD->getDescribedFunctionTemplate(); 3180 assert(NewTemplateDecl && "Template/non-template mismatch"); 3181 if (CXXMethodDecl *Method 3182 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3183 Method->setAccess(OldTemplateDecl->getAccess()); 3184 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3185 } 3186 3187 // If this is an explicit specialization of a member that is a function 3188 // template, mark it as a member specialization. 3189 if (IsExplicitSpecialization && 3190 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3191 NewTemplateDecl->setMemberSpecialization(); 3192 assert(OldTemplateDecl->isMemberSpecialization()); 3193 } 3194 } else { 3195 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3196 NewFD->setAccess(OldDecl->getAccess()); 3197 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3198 } 3199 } 3200 } 3201 3202 // Semantic checking for this function declaration (in isolation). 3203 if (getLangOptions().CPlusPlus) { 3204 // C++-specific checks. 3205 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3206 CheckConstructor(Constructor); 3207 } else if (CXXDestructorDecl *Destructor = 3208 dyn_cast<CXXDestructorDecl>(NewFD)) { 3209 CXXRecordDecl *Record = Destructor->getParent(); 3210 QualType ClassType = Context.getTypeDeclType(Record); 3211 3212 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3213 // type is dependent? Both gcc and edg can handle that. 3214 if (!ClassType->isDependentType()) { 3215 DeclarationName Name 3216 = Context.DeclarationNames.getCXXDestructorName( 3217 Context.getCanonicalType(ClassType)); 3218 if (NewFD->getDeclName() != Name) { 3219 Diag(NewFD->getLocation(), diag::err_destructor_name); 3220 return NewFD->setInvalidDecl(); 3221 } 3222 } 3223 3224 Record->setUserDeclaredDestructor(true); 3225 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3226 // user-defined destructor. 3227 Record->setPOD(false); 3228 3229 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3230 // declared destructor. 3231 // FIXME: C++0x: don't do this for "= default" destructors 3232 Record->setHasTrivialDestructor(false); 3233 } else if (CXXConversionDecl *Conversion 3234 = dyn_cast<CXXConversionDecl>(NewFD)) { 3235 ActOnConversionDeclarator(Conversion); 3236 } 3237 3238 // Find any virtual functions that this function overrides. 3239 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3240 if (!Method->isFunctionTemplateSpecialization() && 3241 !Method->getDescribedFunctionTemplate()) 3242 AddOverriddenMethods(Method->getParent(), Method); 3243 } 3244 3245 // Additional checks for the destructor; make sure we do this after we 3246 // figure out whether the destructor is virtual. 3247 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3248 if (!Destructor->getParent()->isDependentType()) 3249 CheckDestructor(Destructor); 3250 3251 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3252 if (NewFD->isOverloadedOperator() && 3253 CheckOverloadedOperatorDeclaration(NewFD)) 3254 return NewFD->setInvalidDecl(); 3255 3256 // Extra checking for C++0x literal operators (C++0x [over.literal]). 3257 if (NewFD->getLiteralIdentifier() && 3258 CheckLiteralOperatorDeclaration(NewFD)) 3259 return NewFD->setInvalidDecl(); 3260 3261 // In C++, check default arguments now that we have merged decls. Unless 3262 // the lexical context is the class, because in this case this is done 3263 // during delayed parsing anyway. 3264 if (!CurContext->isRecord()) 3265 CheckCXXDefaultArguments(NewFD); 3266 } 3267} 3268 3269void Sema::CheckMain(FunctionDecl* FD) { 3270 // C++ [basic.start.main]p3: A program that declares main to be inline 3271 // or static is ill-formed. 3272 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3273 // shall not appear in a declaration of main. 3274 // static main is not an error under C99, but we should warn about it. 3275 bool isInline = FD->isInlineSpecified(); 3276 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3277 if (isInline || isStatic) { 3278 unsigned diagID = diag::warn_unusual_main_decl; 3279 if (isInline || getLangOptions().CPlusPlus) 3280 diagID = diag::err_unusual_main_decl; 3281 3282 int which = isStatic + (isInline << 1) - 1; 3283 Diag(FD->getLocation(), diagID) << which; 3284 } 3285 3286 QualType T = FD->getType(); 3287 assert(T->isFunctionType() && "function decl is not of function type"); 3288 const FunctionType* FT = T->getAs<FunctionType>(); 3289 3290 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3291 // TODO: add a replacement fixit to turn the return type into 'int'. 3292 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3293 FD->setInvalidDecl(true); 3294 } 3295 3296 // Treat protoless main() as nullary. 3297 if (isa<FunctionNoProtoType>(FT)) return; 3298 3299 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3300 unsigned nparams = FTP->getNumArgs(); 3301 assert(FD->getNumParams() == nparams); 3302 3303 bool HasExtraParameters = (nparams > 3); 3304 3305 // Darwin passes an undocumented fourth argument of type char**. If 3306 // other platforms start sprouting these, the logic below will start 3307 // getting shifty. 3308 if (nparams == 4 && 3309 Context.Target.getTriple().getOS() == llvm::Triple::Darwin) 3310 HasExtraParameters = false; 3311 3312 if (HasExtraParameters) { 3313 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3314 FD->setInvalidDecl(true); 3315 nparams = 3; 3316 } 3317 3318 // FIXME: a lot of the following diagnostics would be improved 3319 // if we had some location information about types. 3320 3321 QualType CharPP = 3322 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3323 QualType Expected[] = { Context.IntTy, CharPP, CharPP, CharPP }; 3324 3325 for (unsigned i = 0; i < nparams; ++i) { 3326 QualType AT = FTP->getArgType(i); 3327 3328 bool mismatch = true; 3329 3330 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3331 mismatch = false; 3332 else if (Expected[i] == CharPP) { 3333 // As an extension, the following forms are okay: 3334 // char const ** 3335 // char const * const * 3336 // char * const * 3337 3338 QualifierCollector qs; 3339 const PointerType* PT; 3340 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3341 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3342 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3343 qs.removeConst(); 3344 mismatch = !qs.empty(); 3345 } 3346 } 3347 3348 if (mismatch) { 3349 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3350 // TODO: suggest replacing given type with expected type 3351 FD->setInvalidDecl(true); 3352 } 3353 } 3354 3355 if (nparams == 1 && !FD->isInvalidDecl()) { 3356 Diag(FD->getLocation(), diag::warn_main_one_arg); 3357 } 3358} 3359 3360bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3361 // FIXME: Need strict checking. In C89, we need to check for 3362 // any assignment, increment, decrement, function-calls, or 3363 // commas outside of a sizeof. In C99, it's the same list, 3364 // except that the aforementioned are allowed in unevaluated 3365 // expressions. Everything else falls under the 3366 // "may accept other forms of constant expressions" exception. 3367 // (We never end up here for C++, so the constant expression 3368 // rules there don't matter.) 3369 if (Init->isConstantInitializer(Context)) 3370 return false; 3371 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3372 << Init->getSourceRange(); 3373 return true; 3374} 3375 3376void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3377 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3378} 3379 3380/// AddInitializerToDecl - Adds the initializer Init to the 3381/// declaration dcl. If DirectInit is true, this is C++ direct 3382/// initialization rather than copy initialization. 3383void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3384 Decl *RealDecl = dcl.getAs<Decl>(); 3385 // If there is no declaration, there was an error parsing it. Just ignore 3386 // the initializer. 3387 if (RealDecl == 0) 3388 return; 3389 3390 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3391 // With declarators parsed the way they are, the parser cannot 3392 // distinguish between a normal initializer and a pure-specifier. 3393 // Thus this grotesque test. 3394 IntegerLiteral *IL; 3395 Expr *Init = static_cast<Expr *>(init.get()); 3396 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3397 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3398 CheckPureMethod(Method, Init->getSourceRange()); 3399 else { 3400 Diag(Method->getLocation(), diag::err_member_function_initialization) 3401 << Method->getDeclName() << Init->getSourceRange(); 3402 Method->setInvalidDecl(); 3403 } 3404 return; 3405 } 3406 3407 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3408 if (!VDecl) { 3409 if (getLangOptions().CPlusPlus && 3410 RealDecl->getLexicalDeclContext()->isRecord() && 3411 isa<NamedDecl>(RealDecl)) 3412 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3413 << cast<NamedDecl>(RealDecl)->getDeclName(); 3414 else 3415 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3416 RealDecl->setInvalidDecl(); 3417 return; 3418 } 3419 3420 // A definition must end up with a complete type, which means it must be 3421 // complete with the restriction that an array type might be completed by the 3422 // initializer; note that later code assumes this restriction. 3423 QualType BaseDeclType = VDecl->getType(); 3424 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3425 BaseDeclType = Array->getElementType(); 3426 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3427 diag::err_typecheck_decl_incomplete_type)) { 3428 RealDecl->setInvalidDecl(); 3429 return; 3430 } 3431 3432 // The variable can not have an abstract class type. 3433 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3434 diag::err_abstract_type_in_decl, 3435 AbstractVariableType)) 3436 VDecl->setInvalidDecl(); 3437 3438 const VarDecl *Def = 0; 3439 if (VDecl->getDefinition(Def)) { 3440 Diag(VDecl->getLocation(), diag::err_redefinition) 3441 << VDecl->getDeclName(); 3442 Diag(Def->getLocation(), diag::note_previous_definition); 3443 VDecl->setInvalidDecl(); 3444 return; 3445 } 3446 3447 // Take ownership of the expression, now that we're sure we have somewhere 3448 // to put it. 3449 Expr *Init = init.takeAs<Expr>(); 3450 assert(Init && "missing initializer"); 3451 3452 // Capture the variable that is being initialized and the style of 3453 // initialization. 3454 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3455 3456 // FIXME: Poor source location information. 3457 InitializationKind Kind 3458 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3459 Init->getLocStart(), 3460 Init->getLocEnd()) 3461 : InitializationKind::CreateCopy(VDecl->getLocation(), 3462 Init->getLocStart()); 3463 3464 // Get the decls type and save a reference for later, since 3465 // CheckInitializerTypes may change it. 3466 QualType DclT = VDecl->getType(), SavT = DclT; 3467 if (VDecl->isBlockVarDecl()) { 3468 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3469 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3470 VDecl->setInvalidDecl(); 3471 } else if (!VDecl->isInvalidDecl()) { 3472 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3473 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3474 MultiExprArg(*this, (void**)&Init, 1), 3475 &DclT); 3476 if (Result.isInvalid()) { 3477 VDecl->setInvalidDecl(); 3478 return; 3479 } 3480 3481 Init = Result.takeAs<Expr>(); 3482 3483 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3484 // Don't check invalid declarations to avoid emitting useless diagnostics. 3485 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3486 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3487 CheckForConstantInitializer(Init, DclT); 3488 } 3489 } 3490 } else if (VDecl->isStaticDataMember() && 3491 VDecl->getLexicalDeclContext()->isRecord()) { 3492 // This is an in-class initialization for a static data member, e.g., 3493 // 3494 // struct S { 3495 // static const int value = 17; 3496 // }; 3497 3498 // Attach the initializer 3499 VDecl->setInit(Context, Init); 3500 3501 // C++ [class.mem]p4: 3502 // A member-declarator can contain a constant-initializer only 3503 // if it declares a static member (9.4) of const integral or 3504 // const enumeration type, see 9.4.2. 3505 QualType T = VDecl->getType(); 3506 if (!T->isDependentType() && 3507 (!Context.getCanonicalType(T).isConstQualified() || 3508 !T->isIntegralType())) { 3509 Diag(VDecl->getLocation(), diag::err_member_initialization) 3510 << VDecl->getDeclName() << Init->getSourceRange(); 3511 VDecl->setInvalidDecl(); 3512 } else { 3513 // C++ [class.static.data]p4: 3514 // If a static data member is of const integral or const 3515 // enumeration type, its declaration in the class definition 3516 // can specify a constant-initializer which shall be an 3517 // integral constant expression (5.19). 3518 if (!Init->isTypeDependent() && 3519 !Init->getType()->isIntegralType()) { 3520 // We have a non-dependent, non-integral or enumeration type. 3521 Diag(Init->getSourceRange().getBegin(), 3522 diag::err_in_class_initializer_non_integral_type) 3523 << Init->getType() << Init->getSourceRange(); 3524 VDecl->setInvalidDecl(); 3525 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3526 // Check whether the expression is a constant expression. 3527 llvm::APSInt Value; 3528 SourceLocation Loc; 3529 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3530 Diag(Loc, diag::err_in_class_initializer_non_constant) 3531 << Init->getSourceRange(); 3532 VDecl->setInvalidDecl(); 3533 } else if (!VDecl->getType()->isDependentType()) 3534 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3535 } 3536 } 3537 } else if (VDecl->isFileVarDecl()) { 3538 if (VDecl->getStorageClass() == VarDecl::Extern) 3539 Diag(VDecl->getLocation(), diag::warn_extern_init); 3540 if (!VDecl->isInvalidDecl()) { 3541 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3542 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3543 MultiExprArg(*this, (void**)&Init, 1), 3544 &DclT); 3545 if (Result.isInvalid()) { 3546 VDecl->setInvalidDecl(); 3547 return; 3548 } 3549 3550 Init = Result.takeAs<Expr>(); 3551 } 3552 3553 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3554 // Don't check invalid declarations to avoid emitting useless diagnostics. 3555 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3556 // C99 6.7.8p4. All file scoped initializers need to be constant. 3557 CheckForConstantInitializer(Init, DclT); 3558 } 3559 } 3560 // If the type changed, it means we had an incomplete type that was 3561 // completed by the initializer. For example: 3562 // int ary[] = { 1, 3, 5 }; 3563 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3564 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3565 VDecl->setType(DclT); 3566 Init->setType(DclT); 3567 } 3568 3569 Init = MaybeCreateCXXExprWithTemporaries(Init); 3570 // Attach the initializer to the decl. 3571 VDecl->setInit(Context, Init); 3572 3573 if (getLangOptions().CPlusPlus) { 3574 // Make sure we mark the destructor as used if necessary. 3575 QualType InitType = VDecl->getType(); 3576 while (const ArrayType *Array = Context.getAsArrayType(InitType)) 3577 InitType = Context.getBaseElementType(Array); 3578 if (InitType->isRecordType()) 3579 FinalizeVarWithDestructor(VDecl, InitType); 3580 } 3581 3582 return; 3583} 3584 3585void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3586 bool TypeContainsUndeducedAuto) { 3587 Decl *RealDecl = dcl.getAs<Decl>(); 3588 3589 // If there is no declaration, there was an error parsing it. Just ignore it. 3590 if (RealDecl == 0) 3591 return; 3592 3593 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3594 QualType Type = Var->getType(); 3595 3596 // Record tentative definitions. 3597 if (Var->isTentativeDefinitionNow()) 3598 TentativeDefinitions.push_back(Var); 3599 3600 // C++ [dcl.init.ref]p3: 3601 // The initializer can be omitted for a reference only in a 3602 // parameter declaration (8.3.5), in the declaration of a 3603 // function return type, in the declaration of a class member 3604 // within its class declaration (9.2), and where the extern 3605 // specifier is explicitly used. 3606 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3607 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3608 << Var->getDeclName() 3609 << SourceRange(Var->getLocation(), Var->getLocation()); 3610 Var->setInvalidDecl(); 3611 return; 3612 } 3613 3614 // C++0x [dcl.spec.auto]p3 3615 if (TypeContainsUndeducedAuto) { 3616 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3617 << Var->getDeclName() << Type; 3618 Var->setInvalidDecl(); 3619 return; 3620 } 3621 3622 // An array without size is an incomplete type, and there are no special 3623 // rules in C++ to make such a definition acceptable. 3624 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3625 !Var->hasExternalStorage()) { 3626 Diag(Var->getLocation(), 3627 diag::err_typecheck_incomplete_array_needs_initializer); 3628 Var->setInvalidDecl(); 3629 return; 3630 } 3631 3632 // C++ [temp.expl.spec]p15: 3633 // An explicit specialization of a static data member of a template is a 3634 // definition if the declaration includes an initializer; otherwise, it 3635 // is a declaration. 3636 if (Var->isStaticDataMember() && 3637 Var->getInstantiatedFromStaticDataMember() && 3638 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3639 return; 3640 3641 // C++ [dcl.init]p9: 3642 // If no initializer is specified for an object, and the object 3643 // is of (possibly cv-qualified) non-POD class type (or array 3644 // thereof), the object shall be default-initialized; if the 3645 // object is of const-qualified type, the underlying class type 3646 // shall have a user-declared default constructor. 3647 // 3648 // FIXME: Diagnose the "user-declared default constructor" bit. 3649 if (getLangOptions().CPlusPlus) { 3650 QualType InitType = Type; 3651 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3652 InitType = Context.getBaseElementType(Array); 3653 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3654 InitType->isRecordType() && !InitType->isDependentType()) { 3655 if (!RequireCompleteType(Var->getLocation(), InitType, 3656 diag::err_invalid_incomplete_type_use)) { 3657 InitializedEntity Entity 3658 = InitializedEntity::InitializeVariable(Var); 3659 InitializationKind Kind 3660 = InitializationKind::CreateDefault(Var->getLocation()); 3661 3662 InitializationSequence InitSeq(*this, Entity, Kind, 0, 0); 3663 OwningExprResult Init = InitSeq.Perform(*this, Entity, Kind, 3664 MultiExprArg(*this, 0, 0)); 3665 if (Init.isInvalid()) 3666 Var->setInvalidDecl(); 3667 else { 3668 Var->setInit(Context, 3669 MaybeCreateCXXExprWithTemporaries(Init.takeAs<Expr>())); 3670 FinalizeVarWithDestructor(Var, InitType); 3671 } 3672 } else { 3673 Var->setInvalidDecl(); 3674 } 3675 } 3676 3677 // The variable can not have an abstract class type. 3678 if (RequireNonAbstractType(Var->getLocation(), Type, 3679 diag::err_abstract_type_in_decl, 3680 AbstractVariableType)) 3681 Var->setInvalidDecl(); 3682 } 3683 3684#if 0 3685 // FIXME: Temporarily disabled because we are not properly parsing 3686 // linkage specifications on declarations, e.g., 3687 // 3688 // extern "C" const CGPoint CGPointerZero; 3689 // 3690 // C++ [dcl.init]p9: 3691 // 3692 // If no initializer is specified for an object, and the 3693 // object is of (possibly cv-qualified) non-POD class type (or 3694 // array thereof), the object shall be default-initialized; if 3695 // the object is of const-qualified type, the underlying class 3696 // type shall have a user-declared default 3697 // constructor. Otherwise, if no initializer is specified for 3698 // an object, the object and its subobjects, if any, have an 3699 // indeterminate initial value; if the object or any of its 3700 // subobjects are of const-qualified type, the program is 3701 // ill-formed. 3702 // 3703 // This isn't technically an error in C, so we don't diagnose it. 3704 // 3705 // FIXME: Actually perform the POD/user-defined default 3706 // constructor check. 3707 if (getLangOptions().CPlusPlus && 3708 Context.getCanonicalType(Type).isConstQualified() && 3709 !Var->hasExternalStorage()) 3710 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3711 << Var->getName() 3712 << SourceRange(Var->getLocation(), Var->getLocation()); 3713#endif 3714 } 3715} 3716 3717Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3718 DeclPtrTy *Group, 3719 unsigned NumDecls) { 3720 llvm::SmallVector<Decl*, 8> Decls; 3721 3722 if (DS.isTypeSpecOwned()) 3723 Decls.push_back((Decl*)DS.getTypeRep()); 3724 3725 for (unsigned i = 0; i != NumDecls; ++i) 3726 if (Decl *D = Group[i].getAs<Decl>()) 3727 Decls.push_back(D); 3728 3729 // Perform semantic analysis that depends on having fully processed both 3730 // the declarator and initializer. 3731 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3732 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3733 if (!IDecl) 3734 continue; 3735 QualType T = IDecl->getType(); 3736 3737 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3738 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3739 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3740 if (T->isDependentType()) { 3741 // If T is dependent, we should not require a complete type. 3742 // (RequireCompleteType shouldn't be called with dependent types.) 3743 // But we still can at least check if we've got an array of unspecified 3744 // size without an initializer. 3745 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3746 !IDecl->getInit()) { 3747 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3748 << T; 3749 IDecl->setInvalidDecl(); 3750 } 3751 } else if (!IDecl->isInvalidDecl()) { 3752 // If T is an incomplete array type with an initializer list that is 3753 // dependent on something, its size has not been fixed. We could attempt 3754 // to fix the size for such arrays, but we would still have to check 3755 // here for initializers containing a C++0x vararg expansion, e.g. 3756 // template <typename... Args> void f(Args... args) { 3757 // int vals[] = { args }; 3758 // } 3759 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3760 Expr *Init = IDecl->getInit(); 3761 if (IAT && Init && 3762 (Init->isTypeDependent() || Init->isValueDependent())) { 3763 // Check that the member type of the array is complete, at least. 3764 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3765 diag::err_typecheck_decl_incomplete_type)) 3766 IDecl->setInvalidDecl(); 3767 } else if (RequireCompleteType(IDecl->getLocation(), T, 3768 diag::err_typecheck_decl_incomplete_type)) 3769 IDecl->setInvalidDecl(); 3770 } 3771 } 3772 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3773 // object that has file scope without an initializer, and without a 3774 // storage-class specifier or with the storage-class specifier "static", 3775 // constitutes a tentative definition. Note: A tentative definition with 3776 // external linkage is valid (C99 6.2.2p5). 3777 if (IDecl->isThisDeclarationADefinition() == VarDecl::TentativeDefinition && 3778 !IDecl->isInvalidDecl()) { 3779 if (const IncompleteArrayType *ArrayT 3780 = Context.getAsIncompleteArrayType(T)) { 3781 if (RequireCompleteType(IDecl->getLocation(), 3782 ArrayT->getElementType(), 3783 diag::err_illegal_decl_array_incomplete_type)) 3784 IDecl->setInvalidDecl(); 3785 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3786 // C99 6.9.2p3: If the declaration of an identifier for an object is 3787 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3788 // declared type shall not be an incomplete type. 3789 // NOTE: code such as the following 3790 // static struct s; 3791 // struct s { int a; }; 3792 // is accepted by gcc. Hence here we issue a warning instead of 3793 // an error and we do not invalidate the static declaration. 3794 // NOTE: to avoid multiple warnings, only check the first declaration. 3795 if (IDecl->getPreviousDeclaration() == 0) 3796 RequireCompleteType(IDecl->getLocation(), T, 3797 diag::ext_typecheck_decl_incomplete_type); 3798 } 3799 } 3800 } 3801 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3802 Decls.data(), Decls.size())); 3803} 3804 3805 3806/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3807/// to introduce parameters into function prototype scope. 3808Sema::DeclPtrTy 3809Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3810 const DeclSpec &DS = D.getDeclSpec(); 3811 3812 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3813 VarDecl::StorageClass StorageClass = VarDecl::None; 3814 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3815 StorageClass = VarDecl::Register; 3816 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3817 Diag(DS.getStorageClassSpecLoc(), 3818 diag::err_invalid_storage_class_in_func_decl); 3819 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3820 } 3821 3822 if (D.getDeclSpec().isThreadSpecified()) 3823 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3824 3825 DiagnoseFunctionSpecifiers(D); 3826 3827 // Check that there are no default arguments inside the type of this 3828 // parameter (C++ only). 3829 if (getLangOptions().CPlusPlus) 3830 CheckExtraCXXDefaultArguments(D); 3831 3832 TypeSourceInfo *TInfo = 0; 3833 TagDecl *OwnedDecl = 0; 3834 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3835 3836 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3837 // C++ [dcl.fct]p6: 3838 // Types shall not be defined in return or parameter types. 3839 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3840 << Context.getTypeDeclType(OwnedDecl); 3841 } 3842 3843 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3844 // Can this happen for params? We already checked that they don't conflict 3845 // among each other. Here they can only shadow globals, which is ok. 3846 IdentifierInfo *II = D.getIdentifier(); 3847 if (II) { 3848 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3849 if (PrevDecl->isTemplateParameter()) { 3850 // Maybe we will complain about the shadowed template parameter. 3851 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3852 // Just pretend that we didn't see the previous declaration. 3853 PrevDecl = 0; 3854 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3855 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3856 3857 // Recover by removing the name 3858 II = 0; 3859 D.SetIdentifier(0, D.getIdentifierLoc()); 3860 } 3861 } 3862 } 3863 3864 // Parameters can not be abstract class types. 3865 // For record types, this is done by the AbstractClassUsageDiagnoser once 3866 // the class has been completely parsed. 3867 if (!CurContext->isRecord() && 3868 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3869 diag::err_abstract_type_in_decl, 3870 AbstractParamType)) 3871 D.setInvalidType(true); 3872 3873 QualType T = adjustParameterType(parmDeclType); 3874 3875 // Temporarily put parameter variables in the translation unit, not 3876 // the enclosing context. This prevents them from accidentally 3877 // looking like class members in C++. 3878 DeclContext *DC = Context.getTranslationUnitDecl(); 3879 3880 ParmVarDecl *New 3881 = ParmVarDecl::Create(Context, DC, D.getIdentifierLoc(), II, 3882 T, TInfo, StorageClass, 0); 3883 3884 if (D.isInvalidType()) 3885 New->setInvalidDecl(); 3886 3887 // Parameter declarators cannot be interface types. All ObjC objects are 3888 // passed by reference. 3889 if (T->isObjCInterfaceType()) { 3890 Diag(D.getIdentifierLoc(), 3891 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3892 New->setInvalidDecl(); 3893 } 3894 3895 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3896 if (D.getCXXScopeSpec().isSet()) { 3897 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3898 << D.getCXXScopeSpec().getRange(); 3899 New->setInvalidDecl(); 3900 } 3901 3902 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3903 // duration shall not be qualified by an address-space qualifier." 3904 // Since all parameters have automatic store duration, they can not have 3905 // an address space. 3906 if (T.getAddressSpace() != 0) { 3907 Diag(D.getIdentifierLoc(), 3908 diag::err_arg_with_address_space); 3909 New->setInvalidDecl(); 3910 } 3911 3912 3913 // Add the parameter declaration into this scope. 3914 S->AddDecl(DeclPtrTy::make(New)); 3915 if (II) 3916 IdResolver.AddDecl(New); 3917 3918 ProcessDeclAttributes(S, New, D); 3919 3920 if (New->hasAttr<BlocksAttr>()) { 3921 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3922 } 3923 return DeclPtrTy::make(New); 3924} 3925 3926void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3927 SourceLocation LocAfterDecls) { 3928 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3929 "Not a function declarator!"); 3930 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3931 3932 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3933 // for a K&R function. 3934 if (!FTI.hasPrototype) { 3935 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3936 --i; 3937 if (FTI.ArgInfo[i].Param == 0) { 3938 llvm::SmallString<256> Code; 3939 llvm::raw_svector_ostream(Code) << " int " 3940 << FTI.ArgInfo[i].Ident->getName() 3941 << ";\n"; 3942 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3943 << FTI.ArgInfo[i].Ident 3944 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3945 3946 // Implicitly declare the argument as type 'int' for lack of a better 3947 // type. 3948 DeclSpec DS; 3949 const char* PrevSpec; // unused 3950 unsigned DiagID; // unused 3951 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3952 PrevSpec, DiagID); 3953 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3954 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3955 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3956 } 3957 } 3958 } 3959} 3960 3961Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3962 Declarator &D) { 3963 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3964 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3965 "Not a function declarator!"); 3966 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3967 3968 if (FTI.hasPrototype) { 3969 // FIXME: Diagnose arguments without names in C. 3970 } 3971 3972 Scope *ParentScope = FnBodyScope->getParent(); 3973 3974 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3975 MultiTemplateParamsArg(*this), 3976 /*IsFunctionDefinition=*/true); 3977 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3978} 3979 3980static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 3981 // Don't warn about invalid declarations. 3982 if (FD->isInvalidDecl()) 3983 return false; 3984 3985 // Or declarations that aren't global. 3986 if (!FD->isGlobal()) 3987 return false; 3988 3989 // Don't warn about C++ member functions. 3990 if (isa<CXXMethodDecl>(FD)) 3991 return false; 3992 3993 // Don't warn about 'main'. 3994 if (FD->isMain()) 3995 return false; 3996 3997 // Don't warn about inline functions. 3998 if (FD->isInlineSpecified()) 3999 return false; 4000 4001 // Don't warn about function templates. 4002 if (FD->getDescribedFunctionTemplate()) 4003 return false; 4004 4005 // Don't warn about function template specializations. 4006 if (FD->isFunctionTemplateSpecialization()) 4007 return false; 4008 4009 bool MissingPrototype = true; 4010 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4011 Prev; Prev = Prev->getPreviousDeclaration()) { 4012 // Ignore any declarations that occur in function or method 4013 // scope, because they aren't visible from the header. 4014 if (Prev->getDeclContext()->isFunctionOrMethod()) 4015 continue; 4016 4017 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4018 break; 4019 } 4020 4021 return MissingPrototype; 4022} 4023 4024Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4025 // Clear the last template instantiation error context. 4026 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4027 4028 if (!D) 4029 return D; 4030 FunctionDecl *FD = 0; 4031 4032 if (FunctionTemplateDecl *FunTmpl 4033 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4034 FD = FunTmpl->getTemplatedDecl(); 4035 else 4036 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4037 4038 CurFunctionNeedsScopeChecking = false; 4039 4040 // See if this is a redefinition. 4041 const FunctionDecl *Definition; 4042 if (FD->getBody(Definition)) { 4043 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4044 Diag(Definition->getLocation(), diag::note_previous_definition); 4045 } 4046 4047 // Builtin functions cannot be defined. 4048 if (unsigned BuiltinID = FD->getBuiltinID()) { 4049 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4050 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4051 FD->setInvalidDecl(); 4052 } 4053 } 4054 4055 // The return type of a function definition must be complete 4056 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4057 QualType ResultType = FD->getResultType(); 4058 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4059 !FD->isInvalidDecl() && 4060 RequireCompleteType(FD->getLocation(), ResultType, 4061 diag::err_func_def_incomplete_result)) 4062 FD->setInvalidDecl(); 4063 4064 // GNU warning -Wmissing-prototypes: 4065 // Warn if a global function is defined without a previous 4066 // prototype declaration. This warning is issued even if the 4067 // definition itself provides a prototype. The aim is to detect 4068 // global functions that fail to be declared in header files. 4069 if (ShouldWarnAboutMissingPrototype(FD)) 4070 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4071 4072 if (FnBodyScope) 4073 PushDeclContext(FnBodyScope, FD); 4074 4075 // Check the validity of our function parameters 4076 CheckParmsForFunctionDef(FD); 4077 4078 // Introduce our parameters into the function scope 4079 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4080 ParmVarDecl *Param = FD->getParamDecl(p); 4081 Param->setOwningFunction(FD); 4082 4083 // If this has an identifier, add it to the scope stack. 4084 if (Param->getIdentifier() && FnBodyScope) 4085 PushOnScopeChains(Param, FnBodyScope); 4086 } 4087 4088 // Checking attributes of current function definition 4089 // dllimport attribute. 4090 if (FD->getAttr<DLLImportAttr>() && 4091 (!FD->getAttr<DLLExportAttr>())) { 4092 // dllimport attribute cannot be applied to definition. 4093 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4094 Diag(FD->getLocation(), 4095 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4096 << "dllimport"; 4097 FD->setInvalidDecl(); 4098 return DeclPtrTy::make(FD); 4099 } else { 4100 // If a symbol previously declared dllimport is later defined, the 4101 // attribute is ignored in subsequent references, and a warning is 4102 // emitted. 4103 Diag(FD->getLocation(), 4104 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4105 << FD->getNameAsCString() << "dllimport"; 4106 } 4107 } 4108 return DeclPtrTy::make(FD); 4109} 4110 4111Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4112 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4113} 4114 4115Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4116 bool IsInstantiation) { 4117 Decl *dcl = D.getAs<Decl>(); 4118 Stmt *Body = BodyArg.takeAs<Stmt>(); 4119 4120 // Don't generate EH edges for CallExprs as we'd like to avoid the n^2 4121 // explosion for destrutors that can result and the compile time hit. 4122 AnalysisContext AC(dcl, false); 4123 FunctionDecl *FD = 0; 4124 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4125 if (FunTmpl) 4126 FD = FunTmpl->getTemplatedDecl(); 4127 else 4128 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4129 4130 if (FD) { 4131 FD->setBody(Body); 4132 if (FD->isMain()) 4133 // C and C++ allow for main to automagically return 0. 4134 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4135 FD->setHasImplicitReturnZero(true); 4136 else 4137 CheckFallThroughForFunctionDef(FD, Body, AC); 4138 4139 if (!FD->isInvalidDecl()) 4140 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4141 4142 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4143 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4144 4145 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4146 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4147 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4148 MD->setBody(Body); 4149 CheckFallThroughForFunctionDef(MD, Body, AC); 4150 MD->setEndLoc(Body->getLocEnd()); 4151 4152 if (!MD->isInvalidDecl()) 4153 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4154 } else { 4155 Body->Destroy(Context); 4156 return DeclPtrTy(); 4157 } 4158 if (!IsInstantiation) 4159 PopDeclContext(); 4160 4161 // Verify and clean out per-function state. 4162 4163 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4164 4165 // Check goto/label use. 4166 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4167 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4168 LabelStmt *L = I->second; 4169 4170 // Verify that we have no forward references left. If so, there was a goto 4171 // or address of a label taken, but no definition of it. Label fwd 4172 // definitions are indicated with a null substmt. 4173 if (L->getSubStmt() != 0) 4174 continue; 4175 4176 // Emit error. 4177 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4178 4179 // At this point, we have gotos that use the bogus label. Stitch it into 4180 // the function body so that they aren't leaked and that the AST is well 4181 // formed. 4182 if (Body == 0) { 4183 // The whole function wasn't parsed correctly, just delete this. 4184 L->Destroy(Context); 4185 continue; 4186 } 4187 4188 // Otherwise, the body is valid: we want to stitch the label decl into the 4189 // function somewhere so that it is properly owned and so that the goto 4190 // has a valid target. Do this by creating a new compound stmt with the 4191 // label in it. 4192 4193 // Give the label a sub-statement. 4194 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4195 4196 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4197 cast<CXXTryStmt>(Body)->getTryBlock() : 4198 cast<CompoundStmt>(Body); 4199 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4200 Elements.push_back(L); 4201 Compound->setStmts(Context, &Elements[0], Elements.size()); 4202 } 4203 FunctionLabelMap.clear(); 4204 4205 if (!Body) return D; 4206 4207 CheckUnreachable(AC); 4208 4209 // Verify that that gotos and switch cases don't jump into scopes illegally. 4210 if (CurFunctionNeedsScopeChecking) 4211 DiagnoseInvalidJumps(Body); 4212 4213 // C++ constructors that have function-try-blocks can't have return 4214 // statements in the handlers of that block. (C++ [except.handle]p14) 4215 // Verify this. 4216 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4217 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4218 4219 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4220 MarkBaseAndMemberDestructorsReferenced(Destructor); 4221 4222 // If any errors have occurred, clear out any temporaries that may have 4223 // been leftover. This ensures that these temporaries won't be picked up for 4224 // deletion in some later function. 4225 if (PP.getDiagnostics().hasErrorOccurred()) 4226 ExprTemporaries.clear(); 4227 4228 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4229 return D; 4230} 4231 4232/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4233/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4234NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4235 IdentifierInfo &II, Scope *S) { 4236 // Before we produce a declaration for an implicitly defined 4237 // function, see whether there was a locally-scoped declaration of 4238 // this name as a function or variable. If so, use that 4239 // (non-visible) declaration, and complain about it. 4240 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4241 = LocallyScopedExternalDecls.find(&II); 4242 if (Pos != LocallyScopedExternalDecls.end()) { 4243 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4244 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4245 return Pos->second; 4246 } 4247 4248 // Extension in C99. Legal in C90, but warn about it. 4249 if (II.getName().startswith("__builtin_")) 4250 Diag(Loc, diag::warn_builtin_unknown) << &II; 4251 else if (getLangOptions().C99) 4252 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4253 else 4254 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4255 4256 // Set a Declarator for the implicit definition: int foo(); 4257 const char *Dummy; 4258 DeclSpec DS; 4259 unsigned DiagID; 4260 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4261 Error = Error; // Silence warning. 4262 assert(!Error && "Error setting up implicit decl!"); 4263 Declarator D(DS, Declarator::BlockContext); 4264 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4265 0, 0, false, SourceLocation(), 4266 false, 0,0,0, Loc, Loc, D), 4267 SourceLocation()); 4268 D.SetIdentifier(&II, Loc); 4269 4270 // Insert this function into translation-unit scope. 4271 4272 DeclContext *PrevDC = CurContext; 4273 CurContext = Context.getTranslationUnitDecl(); 4274 4275 FunctionDecl *FD = 4276 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4277 FD->setImplicit(); 4278 4279 CurContext = PrevDC; 4280 4281 AddKnownFunctionAttributes(FD); 4282 4283 return FD; 4284} 4285 4286/// \brief Adds any function attributes that we know a priori based on 4287/// the declaration of this function. 4288/// 4289/// These attributes can apply both to implicitly-declared builtins 4290/// (like __builtin___printf_chk) or to library-declared functions 4291/// like NSLog or printf. 4292void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4293 if (FD->isInvalidDecl()) 4294 return; 4295 4296 // If this is a built-in function, map its builtin attributes to 4297 // actual attributes. 4298 if (unsigned BuiltinID = FD->getBuiltinID()) { 4299 // Handle printf-formatting attributes. 4300 unsigned FormatIdx; 4301 bool HasVAListArg; 4302 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4303 if (!FD->getAttr<FormatAttr>()) 4304 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4305 HasVAListArg ? 0 : FormatIdx + 2)); 4306 } 4307 4308 // Mark const if we don't care about errno and that is the only 4309 // thing preventing the function from being const. This allows 4310 // IRgen to use LLVM intrinsics for such functions. 4311 if (!getLangOptions().MathErrno && 4312 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4313 if (!FD->getAttr<ConstAttr>()) 4314 FD->addAttr(::new (Context) ConstAttr()); 4315 } 4316 4317 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4318 FD->addAttr(::new (Context) NoReturnAttr()); 4319 if (Context.BuiltinInfo.isNoThrow(BuiltinID)) 4320 FD->addAttr(::new (Context) NoThrowAttr()); 4321 if (Context.BuiltinInfo.isConst(BuiltinID)) 4322 FD->addAttr(::new (Context) ConstAttr()); 4323 } 4324 4325 IdentifierInfo *Name = FD->getIdentifier(); 4326 if (!Name) 4327 return; 4328 if ((!getLangOptions().CPlusPlus && 4329 FD->getDeclContext()->isTranslationUnit()) || 4330 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4331 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4332 LinkageSpecDecl::lang_c)) { 4333 // Okay: this could be a libc/libm/Objective-C function we know 4334 // about. 4335 } else 4336 return; 4337 4338 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4339 // FIXME: NSLog and NSLogv should be target specific 4340 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4341 // FIXME: We known better than our headers. 4342 const_cast<FormatAttr *>(Format)->setType("printf"); 4343 } else 4344 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4345 Name->isStr("NSLogv") ? 0 : 2)); 4346 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4347 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4348 // target-specific builtins, perhaps? 4349 if (!FD->getAttr<FormatAttr>()) 4350 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4351 Name->isStr("vasprintf") ? 0 : 3)); 4352 } 4353} 4354 4355TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4356 TypeSourceInfo *TInfo) { 4357 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4358 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4359 4360 if (!TInfo) { 4361 assert(D.isInvalidType() && "no declarator info for valid type"); 4362 TInfo = Context.getTrivialTypeSourceInfo(T); 4363 } 4364 4365 // Scope manipulation handled by caller. 4366 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4367 D.getIdentifierLoc(), 4368 D.getIdentifier(), 4369 TInfo); 4370 4371 if (const TagType *TT = T->getAs<TagType>()) { 4372 TagDecl *TD = TT->getDecl(); 4373 4374 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4375 // keep track of the TypedefDecl. 4376 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4377 TD->setTypedefForAnonDecl(NewTD); 4378 } 4379 4380 if (D.isInvalidType()) 4381 NewTD->setInvalidDecl(); 4382 return NewTD; 4383} 4384 4385 4386/// \brief Determine whether a tag with a given kind is acceptable 4387/// as a redeclaration of the given tag declaration. 4388/// 4389/// \returns true if the new tag kind is acceptable, false otherwise. 4390bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4391 TagDecl::TagKind NewTag, 4392 SourceLocation NewTagLoc, 4393 const IdentifierInfo &Name) { 4394 // C++ [dcl.type.elab]p3: 4395 // The class-key or enum keyword present in the 4396 // elaborated-type-specifier shall agree in kind with the 4397 // declaration to which the name in theelaborated-type-specifier 4398 // refers. This rule also applies to the form of 4399 // elaborated-type-specifier that declares a class-name or 4400 // friend class since it can be construed as referring to the 4401 // definition of the class. Thus, in any 4402 // elaborated-type-specifier, the enum keyword shall be used to 4403 // refer to an enumeration (7.2), the union class-keyshall be 4404 // used to refer to a union (clause 9), and either the class or 4405 // struct class-key shall be used to refer to a class (clause 9) 4406 // declared using the class or struct class-key. 4407 TagDecl::TagKind OldTag = Previous->getTagKind(); 4408 if (OldTag == NewTag) 4409 return true; 4410 4411 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4412 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4413 // Warn about the struct/class tag mismatch. 4414 bool isTemplate = false; 4415 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4416 isTemplate = Record->getDescribedClassTemplate(); 4417 4418 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4419 << (NewTag == TagDecl::TK_class) 4420 << isTemplate << &Name 4421 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4422 OldTag == TagDecl::TK_class? "class" : "struct"); 4423 Diag(Previous->getLocation(), diag::note_previous_use); 4424 return true; 4425 } 4426 return false; 4427} 4428 4429/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4430/// former case, Name will be non-null. In the later case, Name will be null. 4431/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4432/// reference/declaration/definition of a tag. 4433Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4434 SourceLocation KWLoc, const CXXScopeSpec &SS, 4435 IdentifierInfo *Name, SourceLocation NameLoc, 4436 AttributeList *Attr, AccessSpecifier AS, 4437 MultiTemplateParamsArg TemplateParameterLists, 4438 bool &OwnedDecl, bool &IsDependent) { 4439 // If this is not a definition, it must have a name. 4440 assert((Name != 0 || TUK == TUK_Definition) && 4441 "Nameless record must be a definition!"); 4442 4443 OwnedDecl = false; 4444 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4445 4446 // FIXME: Check explicit specializations more carefully. 4447 bool isExplicitSpecialization = false; 4448 if (TUK != TUK_Reference) { 4449 if (TemplateParameterList *TemplateParams 4450 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4451 (TemplateParameterList**)TemplateParameterLists.get(), 4452 TemplateParameterLists.size(), 4453 isExplicitSpecialization)) { 4454 if (TemplateParams->size() > 0) { 4455 // This is a declaration or definition of a class template (which may 4456 // be a member of another template). 4457 OwnedDecl = false; 4458 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4459 SS, Name, NameLoc, Attr, 4460 TemplateParams, 4461 AS); 4462 TemplateParameterLists.release(); 4463 return Result.get(); 4464 } else { 4465 // The "template<>" header is extraneous. 4466 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4467 << ElaboratedType::getNameForTagKind(Kind) << Name; 4468 isExplicitSpecialization = true; 4469 } 4470 } 4471 4472 TemplateParameterLists.release(); 4473 } 4474 4475 DeclContext *SearchDC = CurContext; 4476 DeclContext *DC = CurContext; 4477 bool isStdBadAlloc = false; 4478 bool Invalid = false; 4479 4480 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4481 : NotForRedeclaration); 4482 4483 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4484 4485 if (Name && SS.isNotEmpty()) { 4486 // We have a nested-name tag ('struct foo::bar'). 4487 4488 // Check for invalid 'foo::'. 4489 if (SS.isInvalid()) { 4490 Name = 0; 4491 goto CreateNewDecl; 4492 } 4493 4494 // If this is a friend or a reference to a class in a dependent 4495 // context, don't try to make a decl for it. 4496 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4497 DC = computeDeclContext(SS, false); 4498 if (!DC) { 4499 IsDependent = true; 4500 return DeclPtrTy(); 4501 } 4502 } 4503 4504 if (RequireCompleteDeclContext(SS)) 4505 return DeclPtrTy::make((Decl *)0); 4506 4507 DC = computeDeclContext(SS, true); 4508 SearchDC = DC; 4509 // Look-up name inside 'foo::'. 4510 LookupQualifiedName(Previous, DC); 4511 4512 if (Previous.isAmbiguous()) 4513 return DeclPtrTy(); 4514 4515 if (Previous.empty()) { 4516 // Name lookup did not find anything. However, if the 4517 // nested-name-specifier refers to the current instantiation, 4518 // and that current instantiation has any dependent base 4519 // classes, we might find something at instantiation time: treat 4520 // this as a dependent elaborated-type-specifier. 4521 if (Previous.wasNotFoundInCurrentInstantiation()) { 4522 IsDependent = true; 4523 return DeclPtrTy(); 4524 } 4525 4526 // A tag 'foo::bar' must already exist. 4527 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4528 Name = 0; 4529 Invalid = true; 4530 goto CreateNewDecl; 4531 } 4532 } else if (Name) { 4533 // If this is a named struct, check to see if there was a previous forward 4534 // declaration or definition. 4535 // FIXME: We're looking into outer scopes here, even when we 4536 // shouldn't be. Doing so can result in ambiguities that we 4537 // shouldn't be diagnosing. 4538 LookupName(Previous, S); 4539 4540 // Note: there used to be some attempt at recovery here. 4541 if (Previous.isAmbiguous()) 4542 return DeclPtrTy(); 4543 4544 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4545 // FIXME: This makes sure that we ignore the contexts associated 4546 // with C structs, unions, and enums when looking for a matching 4547 // tag declaration or definition. See the similar lookup tweak 4548 // in Sema::LookupName; is there a better way to deal with this? 4549 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4550 SearchDC = SearchDC->getParent(); 4551 } 4552 } 4553 4554 if (Previous.isSingleResult() && 4555 Previous.getFoundDecl()->isTemplateParameter()) { 4556 // Maybe we will complain about the shadowed template parameter. 4557 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4558 // Just pretend that we didn't see the previous declaration. 4559 Previous.clear(); 4560 } 4561 4562 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4563 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4564 // This is a declaration of or a reference to "std::bad_alloc". 4565 isStdBadAlloc = true; 4566 4567 if (Previous.empty() && StdBadAlloc) { 4568 // std::bad_alloc has been implicitly declared (but made invisible to 4569 // name lookup). Fill in this implicit declaration as the previous 4570 // declaration, so that the declarations get chained appropriately. 4571 Previous.addDecl(StdBadAlloc); 4572 } 4573 } 4574 4575 if (!Previous.empty()) { 4576 assert(Previous.isSingleResult()); 4577 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4578 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4579 // If this is a use of a previous tag, or if the tag is already declared 4580 // in the same scope (so that the definition/declaration completes or 4581 // rementions the tag), reuse the decl. 4582 if (TUK == TUK_Reference || TUK == TUK_Friend || 4583 isDeclInScope(PrevDecl, SearchDC, S)) { 4584 // Make sure that this wasn't declared as an enum and now used as a 4585 // struct or something similar. 4586 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4587 bool SafeToContinue 4588 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4589 Kind != TagDecl::TK_enum); 4590 if (SafeToContinue) 4591 Diag(KWLoc, diag::err_use_with_wrong_tag) 4592 << Name 4593 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4594 PrevTagDecl->getKindName()); 4595 else 4596 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4597 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4598 4599 if (SafeToContinue) 4600 Kind = PrevTagDecl->getTagKind(); 4601 else { 4602 // Recover by making this an anonymous redefinition. 4603 Name = 0; 4604 Previous.clear(); 4605 Invalid = true; 4606 } 4607 } 4608 4609 if (!Invalid) { 4610 // If this is a use, just return the declaration we found. 4611 4612 // FIXME: In the future, return a variant or some other clue 4613 // for the consumer of this Decl to know it doesn't own it. 4614 // For our current ASTs this shouldn't be a problem, but will 4615 // need to be changed with DeclGroups. 4616 if (TUK == TUK_Reference || TUK == TUK_Friend) 4617 return DeclPtrTy::make(PrevTagDecl); 4618 4619 // Diagnose attempts to redefine a tag. 4620 if (TUK == TUK_Definition) { 4621 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4622 // If we're defining a specialization and the previous definition 4623 // is from an implicit instantiation, don't emit an error 4624 // here; we'll catch this in the general case below. 4625 if (!isExplicitSpecialization || 4626 !isa<CXXRecordDecl>(Def) || 4627 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4628 == TSK_ExplicitSpecialization) { 4629 Diag(NameLoc, diag::err_redefinition) << Name; 4630 Diag(Def->getLocation(), diag::note_previous_definition); 4631 // If this is a redefinition, recover by making this 4632 // struct be anonymous, which will make any later 4633 // references get the previous definition. 4634 Name = 0; 4635 Previous.clear(); 4636 Invalid = true; 4637 } 4638 } else { 4639 // If the type is currently being defined, complain 4640 // about a nested redefinition. 4641 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4642 if (Tag->isBeingDefined()) { 4643 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4644 Diag(PrevTagDecl->getLocation(), 4645 diag::note_previous_definition); 4646 Name = 0; 4647 Previous.clear(); 4648 Invalid = true; 4649 } 4650 } 4651 4652 // Okay, this is definition of a previously declared or referenced 4653 // tag PrevDecl. We're going to create a new Decl for it. 4654 } 4655 } 4656 // If we get here we have (another) forward declaration or we 4657 // have a definition. Just create a new decl. 4658 4659 } else { 4660 // If we get here, this is a definition of a new tag type in a nested 4661 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4662 // new decl/type. We set PrevDecl to NULL so that the entities 4663 // have distinct types. 4664 Previous.clear(); 4665 } 4666 // If we get here, we're going to create a new Decl. If PrevDecl 4667 // is non-NULL, it's a definition of the tag declared by 4668 // PrevDecl. If it's NULL, we have a new definition. 4669 } else { 4670 // PrevDecl is a namespace, template, or anything else 4671 // that lives in the IDNS_Tag identifier namespace. 4672 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4673 // The tag name clashes with a namespace name, issue an error and 4674 // recover by making this tag be anonymous. 4675 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4676 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4677 Name = 0; 4678 Previous.clear(); 4679 Invalid = true; 4680 } else { 4681 // The existing declaration isn't relevant to us; we're in a 4682 // new scope, so clear out the previous declaration. 4683 Previous.clear(); 4684 } 4685 } 4686 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4687 // C++ [basic.scope.pdecl]p5: 4688 // -- for an elaborated-type-specifier of the form 4689 // 4690 // class-key identifier 4691 // 4692 // if the elaborated-type-specifier is used in the 4693 // decl-specifier-seq or parameter-declaration-clause of a 4694 // function defined in namespace scope, the identifier is 4695 // declared as a class-name in the namespace that contains 4696 // the declaration; otherwise, except as a friend 4697 // declaration, the identifier is declared in the smallest 4698 // non-class, non-function-prototype scope that contains the 4699 // declaration. 4700 // 4701 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4702 // C structs and unions. 4703 // 4704 // It is an error in C++ to declare (rather than define) an enum 4705 // type, including via an elaborated type specifier. We'll 4706 // diagnose that later; for now, declare the enum in the same 4707 // scope as we would have picked for any other tag type. 4708 // 4709 // GNU C also supports this behavior as part of its incomplete 4710 // enum types extension, while GNU C++ does not. 4711 // 4712 // Find the context where we'll be declaring the tag. 4713 // FIXME: We would like to maintain the current DeclContext as the 4714 // lexical context, 4715 while (SearchDC->isRecord()) 4716 SearchDC = SearchDC->getParent(); 4717 4718 // Find the scope where we'll be declaring the tag. 4719 while (S->isClassScope() || 4720 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4721 ((S->getFlags() & Scope::DeclScope) == 0) || 4722 (S->getEntity() && 4723 ((DeclContext *)S->getEntity())->isTransparentContext())) 4724 S = S->getParent(); 4725 4726 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4727 // C++ [namespace.memdef]p3: 4728 // If a friend declaration in a non-local class first declares a 4729 // class or function, the friend class or function is a member of 4730 // the innermost enclosing namespace. 4731 while (!SearchDC->isFileContext()) 4732 SearchDC = SearchDC->getParent(); 4733 4734 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4735 while (S->getEntity() != SearchDC) 4736 S = S->getParent(); 4737 } 4738 4739CreateNewDecl: 4740 4741 TagDecl *PrevDecl = 0; 4742 if (Previous.isSingleResult()) 4743 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4744 4745 // If there is an identifier, use the location of the identifier as the 4746 // location of the decl, otherwise use the location of the struct/union 4747 // keyword. 4748 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4749 4750 // Otherwise, create a new declaration. If there is a previous 4751 // declaration of the same entity, the two will be linked via 4752 // PrevDecl. 4753 TagDecl *New; 4754 4755 if (Kind == TagDecl::TK_enum) { 4756 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4757 // enum X { A, B, C } D; D should chain to X. 4758 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4759 cast_or_null<EnumDecl>(PrevDecl)); 4760 // If this is an undefined enum, warn. 4761 if (TUK != TUK_Definition && !Invalid) { 4762 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4763 : diag::ext_forward_ref_enum; 4764 Diag(Loc, DK); 4765 } 4766 } else { 4767 // struct/union/class 4768 4769 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4770 // struct X { int A; } D; D should chain to X. 4771 if (getLangOptions().CPlusPlus) { 4772 // FIXME: Look for a way to use RecordDecl for simple structs. 4773 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4774 cast_or_null<CXXRecordDecl>(PrevDecl)); 4775 4776 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4777 StdBadAlloc = cast<CXXRecordDecl>(New); 4778 } else 4779 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4780 cast_or_null<RecordDecl>(PrevDecl)); 4781 } 4782 4783 if (Kind != TagDecl::TK_enum) { 4784 // Handle #pragma pack: if the #pragma pack stack has non-default 4785 // alignment, make up a packed attribute for this decl. These 4786 // attributes are checked when the ASTContext lays out the 4787 // structure. 4788 // 4789 // It is important for implementing the correct semantics that this 4790 // happen here (in act on tag decl). The #pragma pack stack is 4791 // maintained as a result of parser callbacks which can occur at 4792 // many points during the parsing of a struct declaration (because 4793 // the #pragma tokens are effectively skipped over during the 4794 // parsing of the struct). 4795 if (unsigned Alignment = getPragmaPackAlignment()) 4796 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4797 } 4798 4799 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4800 // C++ [dcl.typedef]p3: 4801 // [...] Similarly, in a given scope, a class or enumeration 4802 // shall not be declared with the same name as a typedef-name 4803 // that is declared in that scope and refers to a type other 4804 // than the class or enumeration itself. 4805 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4806 ForRedeclaration); 4807 LookupName(Lookup, S); 4808 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4809 NamedDecl *PrevTypedefNamed = PrevTypedef; 4810 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4811 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4812 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4813 Diag(Loc, diag::err_tag_definition_of_typedef) 4814 << Context.getTypeDeclType(New) 4815 << PrevTypedef->getUnderlyingType(); 4816 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4817 Invalid = true; 4818 } 4819 } 4820 4821 // If this is a specialization of a member class (of a class template), 4822 // check the specialization. 4823 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4824 Invalid = true; 4825 4826 if (Invalid) 4827 New->setInvalidDecl(); 4828 4829 if (Attr) 4830 ProcessDeclAttributeList(S, New, Attr); 4831 4832 // If we're declaring or defining a tag in function prototype scope 4833 // in C, note that this type can only be used within the function. 4834 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4835 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4836 4837 // Set the lexical context. If the tag has a C++ scope specifier, the 4838 // lexical context will be different from the semantic context. 4839 New->setLexicalDeclContext(CurContext); 4840 4841 // Mark this as a friend decl if applicable. 4842 if (TUK == TUK_Friend) 4843 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4844 4845 // Set the access specifier. 4846 if (!Invalid && TUK != TUK_Friend) 4847 SetMemberAccessSpecifier(New, PrevDecl, AS); 4848 4849 if (TUK == TUK_Definition) 4850 New->startDefinition(); 4851 4852 // If this has an identifier, add it to the scope stack. 4853 if (TUK == TUK_Friend) { 4854 // We might be replacing an existing declaration in the lookup tables; 4855 // if so, borrow its access specifier. 4856 if (PrevDecl) 4857 New->setAccess(PrevDecl->getAccess()); 4858 4859 // Friend tag decls are visible in fairly strange ways. 4860 if (!CurContext->isDependentContext()) { 4861 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4862 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4863 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4864 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4865 } 4866 } else if (Name) { 4867 S = getNonFieldDeclScope(S); 4868 PushOnScopeChains(New, S); 4869 } else { 4870 CurContext->addDecl(New); 4871 } 4872 4873 // If this is the C FILE type, notify the AST context. 4874 if (IdentifierInfo *II = New->getIdentifier()) 4875 if (!New->isInvalidDecl() && 4876 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4877 II->isStr("FILE")) 4878 Context.setFILEDecl(New); 4879 4880 OwnedDecl = true; 4881 return DeclPtrTy::make(New); 4882} 4883 4884void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4885 AdjustDeclIfTemplate(TagD); 4886 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4887 4888 // Enter the tag context. 4889 PushDeclContext(S, Tag); 4890} 4891 4892void Sema::ActOnStartCXXMemberDeclarations(Scope *S, DeclPtrTy TagD, 4893 SourceLocation LBraceLoc) { 4894 AdjustDeclIfTemplate(TagD); 4895 CXXRecordDecl *Record = cast<CXXRecordDecl>(TagD.getAs<Decl>()); 4896 4897 FieldCollector->StartClass(); 4898 4899 if (!Record->getIdentifier()) 4900 return; 4901 4902 // C++ [class]p2: 4903 // [...] The class-name is also inserted into the scope of the 4904 // class itself; this is known as the injected-class-name. For 4905 // purposes of access checking, the injected-class-name is treated 4906 // as if it were a public member name. 4907 CXXRecordDecl *InjectedClassName 4908 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4909 CurContext, Record->getLocation(), 4910 Record->getIdentifier(), 4911 Record->getTagKeywordLoc(), 4912 Record); 4913 InjectedClassName->setImplicit(); 4914 InjectedClassName->setAccess(AS_public); 4915 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4916 InjectedClassName->setDescribedClassTemplate(Template); 4917 PushOnScopeChains(InjectedClassName, S); 4918 assert(InjectedClassName->isInjectedClassName() && 4919 "Broken injected-class-name"); 4920} 4921 4922// Traverses the class and any nested classes, making a note of any 4923// dynamic classes that have no key function so that we can mark all of 4924// their virtual member functions as "used" at the end of the translation 4925// unit. This ensures that all functions needed by the vtable will get 4926// instantiated/synthesized. 4927static void 4928RecordDynamicClassesWithNoKeyFunction(Sema &S, CXXRecordDecl *Record, 4929 SourceLocation Loc) { 4930 // We don't look at dependent or undefined classes. 4931 if (Record->isDependentContext() || !Record->isDefinition()) 4932 return; 4933 4934 if (Record->isDynamicClass() && !S.Context.getKeyFunction(Record)) 4935 S.ClassesWithUnmarkedVirtualMembers.push_back(std::make_pair(Record, Loc)); 4936 4937 for (DeclContext::decl_iterator D = Record->decls_begin(), 4938 DEnd = Record->decls_end(); 4939 D != DEnd; ++D) { 4940 if (CXXRecordDecl *Nested = dyn_cast<CXXRecordDecl>(*D)) 4941 RecordDynamicClassesWithNoKeyFunction(S, Nested, Loc); 4942 } 4943} 4944 4945void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4946 SourceLocation RBraceLoc) { 4947 AdjustDeclIfTemplate(TagD); 4948 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4949 Tag->setRBraceLoc(RBraceLoc); 4950 4951 if (isa<CXXRecordDecl>(Tag)) 4952 FieldCollector->FinishClass(); 4953 4954 // Exit this scope of this tag's definition. 4955 PopDeclContext(); 4956 4957 if (isa<CXXRecordDecl>(Tag) && !Tag->getDeclContext()->isRecord()) 4958 RecordDynamicClassesWithNoKeyFunction(*this, cast<CXXRecordDecl>(Tag), 4959 RBraceLoc); 4960 4961 // Notify the consumer that we've defined a tag. 4962 Consumer.HandleTagDeclDefinition(Tag); 4963} 4964 4965// Note that FieldName may be null for anonymous bitfields. 4966bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4967 QualType FieldTy, const Expr *BitWidth, 4968 bool *ZeroWidth) { 4969 // Default to true; that shouldn't confuse checks for emptiness 4970 if (ZeroWidth) 4971 *ZeroWidth = true; 4972 4973 // C99 6.7.2.1p4 - verify the field type. 4974 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4975 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4976 // Handle incomplete types with specific error. 4977 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4978 return true; 4979 if (FieldName) 4980 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4981 << FieldName << FieldTy << BitWidth->getSourceRange(); 4982 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4983 << FieldTy << BitWidth->getSourceRange(); 4984 } 4985 4986 // If the bit-width is type- or value-dependent, don't try to check 4987 // it now. 4988 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4989 return false; 4990 4991 llvm::APSInt Value; 4992 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4993 return true; 4994 4995 if (Value != 0 && ZeroWidth) 4996 *ZeroWidth = false; 4997 4998 // Zero-width bitfield is ok for anonymous field. 4999 if (Value == 0 && FieldName) 5000 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5001 5002 if (Value.isSigned() && Value.isNegative()) { 5003 if (FieldName) 5004 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5005 << FieldName << Value.toString(10); 5006 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5007 << Value.toString(10); 5008 } 5009 5010 if (!FieldTy->isDependentType()) { 5011 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5012 if (Value.getZExtValue() > TypeSize) { 5013 if (FieldName) 5014 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5015 << FieldName << (unsigned)TypeSize; 5016 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5017 << (unsigned)TypeSize; 5018 } 5019 } 5020 5021 return false; 5022} 5023 5024/// ActOnField - Each field of a struct/union/class is passed into this in order 5025/// to create a FieldDecl object for it. 5026Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5027 SourceLocation DeclStart, 5028 Declarator &D, ExprTy *BitfieldWidth) { 5029 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5030 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5031 AS_public); 5032 return DeclPtrTy::make(Res); 5033} 5034 5035/// HandleField - Analyze a field of a C struct or a C++ data member. 5036/// 5037FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5038 SourceLocation DeclStart, 5039 Declarator &D, Expr *BitWidth, 5040 AccessSpecifier AS) { 5041 IdentifierInfo *II = D.getIdentifier(); 5042 SourceLocation Loc = DeclStart; 5043 if (II) Loc = D.getIdentifierLoc(); 5044 5045 TypeSourceInfo *TInfo = 0; 5046 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5047 if (getLangOptions().CPlusPlus) 5048 CheckExtraCXXDefaultArguments(D); 5049 5050 DiagnoseFunctionSpecifiers(D); 5051 5052 if (D.getDeclSpec().isThreadSpecified()) 5053 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5054 5055 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5056 ForRedeclaration); 5057 5058 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5059 // Maybe we will complain about the shadowed template parameter. 5060 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5061 // Just pretend that we didn't see the previous declaration. 5062 PrevDecl = 0; 5063 } 5064 5065 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5066 PrevDecl = 0; 5067 5068 bool Mutable 5069 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5070 SourceLocation TSSL = D.getSourceRange().getBegin(); 5071 FieldDecl *NewFD 5072 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5073 AS, PrevDecl, &D); 5074 if (NewFD->isInvalidDecl() && PrevDecl) { 5075 // Don't introduce NewFD into scope; there's already something 5076 // with the same name in the same scope. 5077 } else if (II) { 5078 PushOnScopeChains(NewFD, S); 5079 } else 5080 Record->addDecl(NewFD); 5081 5082 return NewFD; 5083} 5084 5085/// \brief Build a new FieldDecl and check its well-formedness. 5086/// 5087/// This routine builds a new FieldDecl given the fields name, type, 5088/// record, etc. \p PrevDecl should refer to any previous declaration 5089/// with the same name and in the same scope as the field to be 5090/// created. 5091/// 5092/// \returns a new FieldDecl. 5093/// 5094/// \todo The Declarator argument is a hack. It will be removed once 5095FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5096 TypeSourceInfo *TInfo, 5097 RecordDecl *Record, SourceLocation Loc, 5098 bool Mutable, Expr *BitWidth, 5099 SourceLocation TSSL, 5100 AccessSpecifier AS, NamedDecl *PrevDecl, 5101 Declarator *D) { 5102 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5103 bool InvalidDecl = false; 5104 if (D) InvalidDecl = D->isInvalidType(); 5105 5106 // If we receive a broken type, recover by assuming 'int' and 5107 // marking this declaration as invalid. 5108 if (T.isNull()) { 5109 InvalidDecl = true; 5110 T = Context.IntTy; 5111 } 5112 5113 QualType EltTy = Context.getBaseElementType(T); 5114 if (!EltTy->isDependentType() && 5115 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5116 InvalidDecl = true; 5117 5118 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5119 // than a variably modified type. 5120 if (!InvalidDecl && T->isVariablyModifiedType()) { 5121 bool SizeIsNegative; 5122 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5123 SizeIsNegative); 5124 if (!FixedTy.isNull()) { 5125 Diag(Loc, diag::warn_illegal_constant_array_size); 5126 T = FixedTy; 5127 } else { 5128 if (SizeIsNegative) 5129 Diag(Loc, diag::err_typecheck_negative_array_size); 5130 else 5131 Diag(Loc, diag::err_typecheck_field_variable_size); 5132 InvalidDecl = true; 5133 } 5134 } 5135 5136 // Fields can not have abstract class types 5137 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5138 diag::err_abstract_type_in_decl, 5139 AbstractFieldType)) 5140 InvalidDecl = true; 5141 5142 bool ZeroWidth = false; 5143 // If this is declared as a bit-field, check the bit-field. 5144 if (!InvalidDecl && BitWidth && 5145 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5146 InvalidDecl = true; 5147 DeleteExpr(BitWidth); 5148 BitWidth = 0; 5149 ZeroWidth = false; 5150 } 5151 5152 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5153 BitWidth, Mutable); 5154 if (InvalidDecl) 5155 NewFD->setInvalidDecl(); 5156 5157 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5158 Diag(Loc, diag::err_duplicate_member) << II; 5159 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5160 NewFD->setInvalidDecl(); 5161 } 5162 5163 if (getLangOptions().CPlusPlus) { 5164 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5165 5166 if (!T->isPODType()) 5167 CXXRecord->setPOD(false); 5168 if (!ZeroWidth) 5169 CXXRecord->setEmpty(false); 5170 5171 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5172 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5173 5174 if (!RDecl->hasTrivialConstructor()) 5175 CXXRecord->setHasTrivialConstructor(false); 5176 if (!RDecl->hasTrivialCopyConstructor()) 5177 CXXRecord->setHasTrivialCopyConstructor(false); 5178 if (!RDecl->hasTrivialCopyAssignment()) 5179 CXXRecord->setHasTrivialCopyAssignment(false); 5180 if (!RDecl->hasTrivialDestructor()) 5181 CXXRecord->setHasTrivialDestructor(false); 5182 5183 // C++ 9.5p1: An object of a class with a non-trivial 5184 // constructor, a non-trivial copy constructor, a non-trivial 5185 // destructor, or a non-trivial copy assignment operator 5186 // cannot be a member of a union, nor can an array of such 5187 // objects. 5188 // TODO: C++0x alters this restriction significantly. 5189 if (Record->isUnion()) { 5190 // We check for copy constructors before constructors 5191 // because otherwise we'll never get complaints about 5192 // copy constructors. 5193 5194 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5195 5196 CXXSpecialMember member; 5197 if (!RDecl->hasTrivialCopyConstructor()) 5198 member = CXXCopyConstructor; 5199 else if (!RDecl->hasTrivialConstructor()) 5200 member = CXXDefaultConstructor; 5201 else if (!RDecl->hasTrivialCopyAssignment()) 5202 member = CXXCopyAssignment; 5203 else if (!RDecl->hasTrivialDestructor()) 5204 member = CXXDestructor; 5205 else 5206 member = invalid; 5207 5208 if (member != invalid) { 5209 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5210 DiagnoseNontrivial(RT, member); 5211 NewFD->setInvalidDecl(); 5212 } 5213 } 5214 } 5215 } 5216 5217 // FIXME: We need to pass in the attributes given an AST 5218 // representation, not a parser representation. 5219 if (D) 5220 // FIXME: What to pass instead of TUScope? 5221 ProcessDeclAttributes(TUScope, NewFD, *D); 5222 5223 if (T.isObjCGCWeak()) 5224 Diag(Loc, diag::warn_attribute_weak_on_field); 5225 5226 NewFD->setAccess(AS); 5227 5228 // C++ [dcl.init.aggr]p1: 5229 // An aggregate is an array or a class (clause 9) with [...] no 5230 // private or protected non-static data members (clause 11). 5231 // A POD must be an aggregate. 5232 if (getLangOptions().CPlusPlus && 5233 (AS == AS_private || AS == AS_protected)) { 5234 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5235 CXXRecord->setAggregate(false); 5236 CXXRecord->setPOD(false); 5237 } 5238 5239 return NewFD; 5240} 5241 5242/// DiagnoseNontrivial - Given that a class has a non-trivial 5243/// special member, figure out why. 5244void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5245 QualType QT(T, 0U); 5246 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5247 5248 // Check whether the member was user-declared. 5249 switch (member) { 5250 case CXXDefaultConstructor: 5251 if (RD->hasUserDeclaredConstructor()) { 5252 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5253 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5254 const FunctionDecl *body = 0; 5255 ci->getBody(body); 5256 if (!body || 5257 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5258 SourceLocation CtorLoc = ci->getLocation(); 5259 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5260 return; 5261 } 5262 } 5263 5264 assert(0 && "found no user-declared constructors"); 5265 return; 5266 } 5267 break; 5268 5269 case CXXCopyConstructor: 5270 if (RD->hasUserDeclaredCopyConstructor()) { 5271 SourceLocation CtorLoc = 5272 RD->getCopyConstructor(Context, 0)->getLocation(); 5273 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5274 return; 5275 } 5276 break; 5277 5278 case CXXCopyAssignment: 5279 if (RD->hasUserDeclaredCopyAssignment()) { 5280 // FIXME: this should use the location of the copy 5281 // assignment, not the type. 5282 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5283 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5284 return; 5285 } 5286 break; 5287 5288 case CXXDestructor: 5289 if (RD->hasUserDeclaredDestructor()) { 5290 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5291 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5292 return; 5293 } 5294 break; 5295 } 5296 5297 typedef CXXRecordDecl::base_class_iterator base_iter; 5298 5299 // Virtual bases and members inhibit trivial copying/construction, 5300 // but not trivial destruction. 5301 if (member != CXXDestructor) { 5302 // Check for virtual bases. vbases includes indirect virtual bases, 5303 // so we just iterate through the direct bases. 5304 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5305 if (bi->isVirtual()) { 5306 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5307 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5308 return; 5309 } 5310 5311 // Check for virtual methods. 5312 typedef CXXRecordDecl::method_iterator meth_iter; 5313 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5314 ++mi) { 5315 if (mi->isVirtual()) { 5316 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5317 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5318 return; 5319 } 5320 } 5321 } 5322 5323 bool (CXXRecordDecl::*hasTrivial)() const; 5324 switch (member) { 5325 case CXXDefaultConstructor: 5326 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5327 case CXXCopyConstructor: 5328 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5329 case CXXCopyAssignment: 5330 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5331 case CXXDestructor: 5332 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5333 default: 5334 assert(0 && "unexpected special member"); return; 5335 } 5336 5337 // Check for nontrivial bases (and recurse). 5338 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5339 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5340 assert(BaseRT && "Don't know how to handle dependent bases"); 5341 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5342 if (!(BaseRecTy->*hasTrivial)()) { 5343 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5344 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5345 DiagnoseNontrivial(BaseRT, member); 5346 return; 5347 } 5348 } 5349 5350 // Check for nontrivial members (and recurse). 5351 typedef RecordDecl::field_iterator field_iter; 5352 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5353 ++fi) { 5354 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5355 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5356 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5357 5358 if (!(EltRD->*hasTrivial)()) { 5359 SourceLocation FLoc = (*fi)->getLocation(); 5360 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5361 DiagnoseNontrivial(EltRT, member); 5362 return; 5363 } 5364 } 5365 } 5366 5367 assert(0 && "found no explanation for non-trivial member"); 5368} 5369 5370/// TranslateIvarVisibility - Translate visibility from a token ID to an 5371/// AST enum value. 5372static ObjCIvarDecl::AccessControl 5373TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5374 switch (ivarVisibility) { 5375 default: assert(0 && "Unknown visitibility kind"); 5376 case tok::objc_private: return ObjCIvarDecl::Private; 5377 case tok::objc_public: return ObjCIvarDecl::Public; 5378 case tok::objc_protected: return ObjCIvarDecl::Protected; 5379 case tok::objc_package: return ObjCIvarDecl::Package; 5380 } 5381} 5382 5383/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5384/// in order to create an IvarDecl object for it. 5385Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5386 SourceLocation DeclStart, 5387 DeclPtrTy IntfDecl, 5388 Declarator &D, ExprTy *BitfieldWidth, 5389 tok::ObjCKeywordKind Visibility) { 5390 5391 IdentifierInfo *II = D.getIdentifier(); 5392 Expr *BitWidth = (Expr*)BitfieldWidth; 5393 SourceLocation Loc = DeclStart; 5394 if (II) Loc = D.getIdentifierLoc(); 5395 5396 // FIXME: Unnamed fields can be handled in various different ways, for 5397 // example, unnamed unions inject all members into the struct namespace! 5398 5399 TypeSourceInfo *TInfo = 0; 5400 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5401 5402 if (BitWidth) { 5403 // 6.7.2.1p3, 6.7.2.1p4 5404 if (VerifyBitField(Loc, II, T, BitWidth)) { 5405 D.setInvalidType(); 5406 DeleteExpr(BitWidth); 5407 BitWidth = 0; 5408 } 5409 } else { 5410 // Not a bitfield. 5411 5412 // validate II. 5413 5414 } 5415 5416 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5417 // than a variably modified type. 5418 if (T->isVariablyModifiedType()) { 5419 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5420 D.setInvalidType(); 5421 } 5422 5423 // Get the visibility (access control) for this ivar. 5424 ObjCIvarDecl::AccessControl ac = 5425 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5426 : ObjCIvarDecl::None; 5427 // Must set ivar's DeclContext to its enclosing interface. 5428 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5429 DeclContext *EnclosingContext; 5430 if (ObjCImplementationDecl *IMPDecl = 5431 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5432 // Case of ivar declared in an implementation. Context is that of its class. 5433 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5434 assert(IDecl && "No class- ActOnIvar"); 5435 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5436 } else 5437 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5438 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5439 5440 // Construct the decl. 5441 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5442 EnclosingContext, Loc, II, T, 5443 TInfo, ac, (Expr *)BitfieldWidth); 5444 5445 if (II) { 5446 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5447 ForRedeclaration); 5448 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5449 && !isa<TagDecl>(PrevDecl)) { 5450 Diag(Loc, diag::err_duplicate_member) << II; 5451 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5452 NewID->setInvalidDecl(); 5453 } 5454 } 5455 5456 // Process attributes attached to the ivar. 5457 ProcessDeclAttributes(S, NewID, D); 5458 5459 if (D.isInvalidType()) 5460 NewID->setInvalidDecl(); 5461 5462 if (II) { 5463 // FIXME: When interfaces are DeclContexts, we'll need to add 5464 // these to the interface. 5465 S->AddDecl(DeclPtrTy::make(NewID)); 5466 IdResolver.AddDecl(NewID); 5467 } 5468 5469 return DeclPtrTy::make(NewID); 5470} 5471 5472void Sema::ActOnFields(Scope* S, 5473 SourceLocation RecLoc, DeclPtrTy RecDecl, 5474 DeclPtrTy *Fields, unsigned NumFields, 5475 SourceLocation LBrac, SourceLocation RBrac, 5476 AttributeList *Attr) { 5477 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5478 assert(EnclosingDecl && "missing record or interface decl"); 5479 5480 // If the decl this is being inserted into is invalid, then it may be a 5481 // redeclaration or some other bogus case. Don't try to add fields to it. 5482 if (EnclosingDecl->isInvalidDecl()) { 5483 // FIXME: Deallocate fields? 5484 return; 5485 } 5486 5487 5488 // Verify that all the fields are okay. 5489 unsigned NumNamedMembers = 0; 5490 llvm::SmallVector<FieldDecl*, 32> RecFields; 5491 5492 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5493 for (unsigned i = 0; i != NumFields; ++i) { 5494 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5495 5496 // Get the type for the field. 5497 Type *FDTy = FD->getType().getTypePtr(); 5498 5499 if (!FD->isAnonymousStructOrUnion()) { 5500 // Remember all fields written by the user. 5501 RecFields.push_back(FD); 5502 } 5503 5504 // If the field is already invalid for some reason, don't emit more 5505 // diagnostics about it. 5506 if (FD->isInvalidDecl()) { 5507 EnclosingDecl->setInvalidDecl(); 5508 continue; 5509 } 5510 5511 // C99 6.7.2.1p2: 5512 // A structure or union shall not contain a member with 5513 // incomplete or function type (hence, a structure shall not 5514 // contain an instance of itself, but may contain a pointer to 5515 // an instance of itself), except that the last member of a 5516 // structure with more than one named member may have incomplete 5517 // array type; such a structure (and any union containing, 5518 // possibly recursively, a member that is such a structure) 5519 // shall not be a member of a structure or an element of an 5520 // array. 5521 if (FDTy->isFunctionType()) { 5522 // Field declared as a function. 5523 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5524 << FD->getDeclName(); 5525 FD->setInvalidDecl(); 5526 EnclosingDecl->setInvalidDecl(); 5527 continue; 5528 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5529 Record && Record->isStruct()) { 5530 // Flexible array member. 5531 if (NumNamedMembers < 1) { 5532 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5533 << FD->getDeclName(); 5534 FD->setInvalidDecl(); 5535 EnclosingDecl->setInvalidDecl(); 5536 continue; 5537 } 5538 // Okay, we have a legal flexible array member at the end of the struct. 5539 if (Record) 5540 Record->setHasFlexibleArrayMember(true); 5541 } else if (!FDTy->isDependentType() && 5542 RequireCompleteType(FD->getLocation(), FD->getType(), 5543 diag::err_field_incomplete)) { 5544 // Incomplete type 5545 FD->setInvalidDecl(); 5546 EnclosingDecl->setInvalidDecl(); 5547 continue; 5548 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5549 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5550 // If this is a member of a union, then entire union becomes "flexible". 5551 if (Record && Record->isUnion()) { 5552 Record->setHasFlexibleArrayMember(true); 5553 } else { 5554 // If this is a struct/class and this is not the last element, reject 5555 // it. Note that GCC supports variable sized arrays in the middle of 5556 // structures. 5557 if (i != NumFields-1) 5558 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5559 << FD->getDeclName() << FD->getType(); 5560 else { 5561 // We support flexible arrays at the end of structs in 5562 // other structs as an extension. 5563 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5564 << FD->getDeclName(); 5565 if (Record) 5566 Record->setHasFlexibleArrayMember(true); 5567 } 5568 } 5569 } 5570 if (Record && FDTTy->getDecl()->hasObjectMember()) 5571 Record->setHasObjectMember(true); 5572 } else if (FDTy->isObjCInterfaceType()) { 5573 /// A field cannot be an Objective-c object 5574 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5575 FD->setInvalidDecl(); 5576 EnclosingDecl->setInvalidDecl(); 5577 continue; 5578 } else if (getLangOptions().ObjC1 && 5579 getLangOptions().getGCMode() != LangOptions::NonGC && 5580 Record && 5581 (FD->getType()->isObjCObjectPointerType() || 5582 FD->getType().isObjCGCStrong())) 5583 Record->setHasObjectMember(true); 5584 // Keep track of the number of named members. 5585 if (FD->getIdentifier()) 5586 ++NumNamedMembers; 5587 } 5588 5589 // Okay, we successfully defined 'Record'. 5590 if (Record) { 5591 Record->completeDefinition(Context); 5592 } else { 5593 ObjCIvarDecl **ClsFields = 5594 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5595 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5596 ID->setIVarList(ClsFields, RecFields.size(), Context); 5597 ID->setLocEnd(RBrac); 5598 // Add ivar's to class's DeclContext. 5599 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5600 ClsFields[i]->setLexicalDeclContext(ID); 5601 ID->addDecl(ClsFields[i]); 5602 } 5603 // Must enforce the rule that ivars in the base classes may not be 5604 // duplicates. 5605 if (ID->getSuperClass()) { 5606 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5607 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5608 ObjCIvarDecl* Ivar = (*IVI); 5609 5610 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5611 ObjCIvarDecl* prevIvar = 5612 ID->getSuperClass()->lookupInstanceVariable(II); 5613 if (prevIvar) { 5614 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5615 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5616 } 5617 } 5618 } 5619 } 5620 } else if (ObjCImplementationDecl *IMPDecl = 5621 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5622 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5623 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5624 // Ivar declared in @implementation never belongs to the implementation. 5625 // Only it is in implementation's lexical context. 5626 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5627 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5628 } 5629 } 5630 5631 if (Attr) 5632 ProcessDeclAttributeList(S, Record, Attr); 5633} 5634 5635EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5636 EnumConstantDecl *LastEnumConst, 5637 SourceLocation IdLoc, 5638 IdentifierInfo *Id, 5639 ExprArg val) { 5640 Expr *Val = (Expr *)val.get(); 5641 5642 llvm::APSInt EnumVal(32); 5643 QualType EltTy; 5644 if (Val) { 5645 if (Enum->isDependentType()) 5646 EltTy = Context.DependentTy; 5647 else { 5648 // Make sure to promote the operand type to int. 5649 UsualUnaryConversions(Val); 5650 if (Val != val.get()) { 5651 val.release(); 5652 val = Val; 5653 } 5654 5655 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5656 SourceLocation ExpLoc; 5657 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 5658 Val = 0; 5659 } else { 5660 EltTy = Val->getType(); 5661 } 5662 } 5663 } 5664 5665 if (!Val) { 5666 if (Enum->isDependentType()) 5667 EltTy = Context.DependentTy; 5668 else if (LastEnumConst) { 5669 // Assign the last value + 1. 5670 EnumVal = LastEnumConst->getInitVal(); 5671 ++EnumVal; 5672 5673 // Check for overflow on increment. 5674 if (EnumVal < LastEnumConst->getInitVal()) 5675 Diag(IdLoc, diag::warn_enum_value_overflow); 5676 5677 EltTy = LastEnumConst->getType(); 5678 } else { 5679 // First value, set to zero. 5680 EltTy = Context.IntTy; 5681 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5682 EnumVal.setIsSigned(true); 5683 } 5684 } 5685 5686 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5687 5688 val.release(); 5689 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5690 Val, EnumVal); 5691} 5692 5693 5694Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5695 DeclPtrTy lastEnumConst, 5696 SourceLocation IdLoc, 5697 IdentifierInfo *Id, 5698 SourceLocation EqualLoc, ExprTy *val) { 5699 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5700 EnumConstantDecl *LastEnumConst = 5701 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5702 Expr *Val = static_cast<Expr*>(val); 5703 5704 // The scope passed in may not be a decl scope. Zip up the scope tree until 5705 // we find one that is. 5706 S = getNonFieldDeclScope(S); 5707 5708 // Verify that there isn't already something declared with this name in this 5709 // scope. 5710 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName, 5711 ForRedeclaration); 5712 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5713 // Maybe we will complain about the shadowed template parameter. 5714 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5715 // Just pretend that we didn't see the previous declaration. 5716 PrevDecl = 0; 5717 } 5718 5719 if (PrevDecl) { 5720 // When in C++, we may get a TagDecl with the same name; in this case the 5721 // enum constant will 'hide' the tag. 5722 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5723 "Received TagDecl when not in C++!"); 5724 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5725 if (isa<EnumConstantDecl>(PrevDecl)) 5726 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5727 else 5728 Diag(IdLoc, diag::err_redefinition) << Id; 5729 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5730 if (Val) Val->Destroy(Context); 5731 return DeclPtrTy(); 5732 } 5733 } 5734 5735 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5736 IdLoc, Id, Owned(Val)); 5737 5738 // Register this decl in the current scope stack. 5739 if (New) { 5740 New->setAccess(TheEnumDecl->getAccess()); 5741 PushOnScopeChains(New, S); 5742 } 5743 5744 return DeclPtrTy::make(New); 5745} 5746 5747void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5748 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5749 DeclPtrTy *Elements, unsigned NumElements, 5750 Scope *S, AttributeList *Attr) { 5751 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5752 QualType EnumType = Context.getTypeDeclType(Enum); 5753 5754 if (Attr) 5755 ProcessDeclAttributeList(S, Enum, Attr); 5756 5757 if (Enum->isDependentType()) { 5758 for (unsigned i = 0; i != NumElements; ++i) { 5759 EnumConstantDecl *ECD = 5760 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5761 if (!ECD) continue; 5762 5763 ECD->setType(EnumType); 5764 } 5765 5766 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 5767 return; 5768 } 5769 5770 // TODO: If the result value doesn't fit in an int, it must be a long or long 5771 // long value. ISO C does not support this, but GCC does as an extension, 5772 // emit a warning. 5773 unsigned IntWidth = Context.Target.getIntWidth(); 5774 unsigned CharWidth = Context.Target.getCharWidth(); 5775 unsigned ShortWidth = Context.Target.getShortWidth(); 5776 5777 // Verify that all the values are okay, compute the size of the values, and 5778 // reverse the list. 5779 unsigned NumNegativeBits = 0; 5780 unsigned NumPositiveBits = 0; 5781 5782 // Keep track of whether all elements have type int. 5783 bool AllElementsInt = true; 5784 5785 for (unsigned i = 0; i != NumElements; ++i) { 5786 EnumConstantDecl *ECD = 5787 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5788 if (!ECD) continue; // Already issued a diagnostic. 5789 5790 // If the enum value doesn't fit in an int, emit an extension warning. 5791 const llvm::APSInt &InitVal = ECD->getInitVal(); 5792 assert(InitVal.getBitWidth() >= IntWidth && 5793 "Should have promoted value to int"); 5794 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 5795 llvm::APSInt V(InitVal); 5796 V.trunc(IntWidth); 5797 V.extend(InitVal.getBitWidth()); 5798 if (V != InitVal) 5799 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5800 << InitVal.toString(10); 5801 } 5802 5803 // Keep track of the size of positive and negative values. 5804 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5805 NumPositiveBits = std::max(NumPositiveBits, 5806 (unsigned)InitVal.getActiveBits()); 5807 else 5808 NumNegativeBits = std::max(NumNegativeBits, 5809 (unsigned)InitVal.getMinSignedBits()); 5810 5811 // Keep track of whether every enum element has type int (very commmon). 5812 if (AllElementsInt) 5813 AllElementsInt = ECD->getType() == Context.IntTy; 5814 } 5815 5816 // Figure out the type that should be used for this enum. 5817 // FIXME: Support -fshort-enums. 5818 QualType BestType; 5819 unsigned BestWidth; 5820 5821 // C++0x N3000 [conv.prom]p3: 5822 // An rvalue of an unscoped enumeration type whose underlying 5823 // type is not fixed can be converted to an rvalue of the first 5824 // of the following types that can represent all the values of 5825 // the enumeration: int, unsigned int, long int, unsigned long 5826 // int, long long int, or unsigned long long int. 5827 // C99 6.4.4.3p2: 5828 // An identifier declared as an enumeration constant has type int. 5829 // The C99 rule is modified by a gcc extension 5830 QualType BestPromotionType; 5831 5832 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5833 5834 if (NumNegativeBits) { 5835 // If there is a negative value, figure out the smallest integer type (of 5836 // int/long/longlong) that fits. 5837 // If it's packed, check also if it fits a char or a short. 5838 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5839 BestType = Context.SignedCharTy; 5840 BestWidth = CharWidth; 5841 } else if (Packed && NumNegativeBits <= ShortWidth && 5842 NumPositiveBits < ShortWidth) { 5843 BestType = Context.ShortTy; 5844 BestWidth = ShortWidth; 5845 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5846 BestType = Context.IntTy; 5847 BestWidth = IntWidth; 5848 } else { 5849 BestWidth = Context.Target.getLongWidth(); 5850 5851 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5852 BestType = Context.LongTy; 5853 } else { 5854 BestWidth = Context.Target.getLongLongWidth(); 5855 5856 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5857 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5858 BestType = Context.LongLongTy; 5859 } 5860 } 5861 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5862 } else { 5863 // If there is no negative value, figure out which of uint, ulong, ulonglong 5864 // fits. 5865 // If it's packed, check also if it fits a char or a short. 5866 if (Packed && NumPositiveBits <= CharWidth) { 5867 BestType = Context.UnsignedCharTy; 5868 BestPromotionType = Context.IntTy; 5869 BestWidth = CharWidth; 5870 } else if (Packed && NumPositiveBits <= ShortWidth) { 5871 BestType = Context.UnsignedShortTy; 5872 BestPromotionType = Context.IntTy; 5873 BestWidth = ShortWidth; 5874 } else if (NumPositiveBits <= IntWidth) { 5875 BestType = Context.UnsignedIntTy; 5876 BestWidth = IntWidth; 5877 BestPromotionType = (NumPositiveBits == BestWidth 5878 ? Context.UnsignedIntTy : Context.IntTy); 5879 } else if (NumPositiveBits <= 5880 (BestWidth = Context.Target.getLongWidth())) { 5881 BestType = Context.UnsignedLongTy; 5882 BestPromotionType = (NumPositiveBits == BestWidth 5883 ? Context.UnsignedLongTy : Context.LongTy); 5884 } else { 5885 BestWidth = Context.Target.getLongLongWidth(); 5886 assert(NumPositiveBits <= BestWidth && 5887 "How could an initializer get larger than ULL?"); 5888 BestType = Context.UnsignedLongLongTy; 5889 BestPromotionType = (NumPositiveBits == BestWidth 5890 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5891 } 5892 } 5893 5894 // If we're in C and the promotion type is larger than an int, just 5895 // use the underlying type, which is generally the unsigned integer 5896 // type of the same rank as the promotion type. This is how the gcc 5897 // extension works. 5898 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5899 BestPromotionType = BestType; 5900 5901 // Loop over all of the enumerator constants, changing their types to match 5902 // the type of the enum if needed. 5903 for (unsigned i = 0; i != NumElements; ++i) { 5904 EnumConstantDecl *ECD = 5905 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5906 if (!ECD) continue; // Already issued a diagnostic. 5907 5908 // Standard C says the enumerators have int type, but we allow, as an 5909 // extension, the enumerators to be larger than int size. If each 5910 // enumerator value fits in an int, type it as an int, otherwise type it the 5911 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5912 // that X has type 'int', not 'unsigned'. 5913 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 5914 continue; 5915 5916 // Determine whether the value fits into an int. 5917 llvm::APSInt InitVal = ECD->getInitVal(); 5918 bool FitsInInt; 5919 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5920 FitsInInt = InitVal.getActiveBits() < IntWidth; 5921 else 5922 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5923 5924 // If it fits into an integer type, force it. Otherwise force it to match 5925 // the enum decl type. 5926 QualType NewTy; 5927 unsigned NewWidth; 5928 bool NewSign; 5929 if (FitsInInt && !getLangOptions().CPlusPlus) { 5930 NewTy = Context.IntTy; 5931 NewWidth = IntWidth; 5932 NewSign = true; 5933 } else if (ECD->getType() == BestType) { 5934 // Already the right type! 5935 if (getLangOptions().CPlusPlus) 5936 // C++ [dcl.enum]p4: Following the closing brace of an 5937 // enum-specifier, each enumerator has the type of its 5938 // enumeration. 5939 ECD->setType(EnumType); 5940 continue; 5941 } else { 5942 NewTy = BestType; 5943 NewWidth = BestWidth; 5944 NewSign = BestType->isSignedIntegerType(); 5945 } 5946 5947 // Adjust the APSInt value. 5948 InitVal.extOrTrunc(NewWidth); 5949 InitVal.setIsSigned(NewSign); 5950 ECD->setInitVal(InitVal); 5951 5952 // Adjust the Expr initializer and type. 5953 if (ECD->getInitExpr()) 5954 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5955 CastExpr::CK_IntegralCast, 5956 ECD->getInitExpr(), 5957 /*isLvalue=*/false)); 5958 if (getLangOptions().CPlusPlus) 5959 // C++ [dcl.enum]p4: Following the closing brace of an 5960 // enum-specifier, each enumerator has the type of its 5961 // enumeration. 5962 ECD->setType(EnumType); 5963 else 5964 ECD->setType(NewTy); 5965 } 5966 5967 Enum->completeDefinition(Context, BestType, BestPromotionType); 5968} 5969 5970Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5971 ExprArg expr) { 5972 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5973 5974 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5975 Loc, AsmString); 5976 CurContext->addDecl(New); 5977 return DeclPtrTy::make(New); 5978} 5979 5980void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5981 SourceLocation PragmaLoc, 5982 SourceLocation NameLoc) { 5983 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5984 5985 if (PrevDecl) { 5986 PrevDecl->addAttr(::new (Context) WeakAttr()); 5987 } else { 5988 (void)WeakUndeclaredIdentifiers.insert( 5989 std::pair<IdentifierInfo*,WeakInfo> 5990 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5991 } 5992} 5993 5994void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5995 IdentifierInfo* AliasName, 5996 SourceLocation PragmaLoc, 5997 SourceLocation NameLoc, 5998 SourceLocation AliasNameLoc) { 5999 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6000 WeakInfo W = WeakInfo(Name, NameLoc); 6001 6002 if (PrevDecl) { 6003 if (!PrevDecl->hasAttr<AliasAttr>()) 6004 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6005 DeclApplyPragmaWeak(TUScope, ND, W); 6006 } else { 6007 (void)WeakUndeclaredIdentifiers.insert( 6008 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6009 } 6010} 6011