SemaDecl.cpp revision 0dd7ceb72cc369195d698ccc26c70ac0e56ab945
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/Analysis/CFG.h" 21#include "clang/AST/CXXInheritance.h" 22#include "clang/AST/DeclObjC.h" 23#include "clang/AST/DeclTemplate.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/StmtCXX.h" 26#include "clang/AST/StmtObjC.h" 27#include "clang/Parse/DeclSpec.h" 28#include "clang/Parse/ParseDiagnostic.h" 29#include "clang/Parse/Template.h" 30#include "clang/Basic/PartialDiagnostic.h" 31#include "clang/Basic/SourceManager.h" 32#include "clang/Basic/TargetInfo.h" 33// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 34#include "clang/Lex/Preprocessor.h" 35#include "clang/Lex/HeaderSearch.h" 36#include "llvm/ADT/BitVector.h" 37#include "llvm/ADT/STLExtras.h" 38#include <algorithm> 39#include <cstring> 40#include <functional> 41#include <queue> 42using namespace clang; 43 44/// getDeclName - Return a pretty name for the specified decl if possible, or 45/// an empty string if not. This is used for pretty crash reporting. 46std::string Sema::getDeclName(DeclPtrTy d) { 47 Decl *D = d.getAs<Decl>(); 48 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 49 return DN->getQualifiedNameAsString(); 50 return ""; 51} 52 53Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 54 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 55} 56 57/// \brief If the identifier refers to a type name within this scope, 58/// return the declaration of that type. 59/// 60/// This routine performs ordinary name lookup of the identifier II 61/// within the given scope, with optional C++ scope specifier SS, to 62/// determine whether the name refers to a type. If so, returns an 63/// opaque pointer (actually a QualType) corresponding to that 64/// type. Otherwise, returns NULL. 65/// 66/// If name lookup results in an ambiguity, this routine will complain 67/// and then return NULL. 68Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 69 Scope *S, const CXXScopeSpec *SS, 70 bool isClassName, 71 TypeTy *ObjectTypePtr) { 72 // Determine where we will perform name lookup. 73 DeclContext *LookupCtx = 0; 74 if (ObjectTypePtr) { 75 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 76 if (ObjectType->isRecordType()) 77 LookupCtx = computeDeclContext(ObjectType); 78 } else if (SS && SS->isSet()) { 79 LookupCtx = computeDeclContext(*SS, false); 80 81 if (!LookupCtx) { 82 if (isDependentScopeSpecifier(*SS)) { 83 // C++ [temp.res]p3: 84 // A qualified-id that refers to a type and in which the 85 // nested-name-specifier depends on a template-parameter (14.6.2) 86 // shall be prefixed by the keyword typename to indicate that the 87 // qualified-id denotes a type, forming an 88 // elaborated-type-specifier (7.1.5.3). 89 // 90 // We therefore do not perform any name lookup if the result would 91 // refer to a member of an unknown specialization. 92 if (!isClassName) 93 return 0; 94 95 // We know from the grammar that this name refers to a type, so build a 96 // TypenameType node to describe the type. 97 // FIXME: Record somewhere that this TypenameType node has no "typename" 98 // keyword associated with it. 99 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 100 II, SS->getRange()).getAsOpaquePtr(); 101 } 102 103 return 0; 104 } 105 106 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 107 return 0; 108 } 109 110 LookupResult Result(*this, &II, NameLoc, LookupOrdinaryName); 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::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 return 0; 138 139 case LookupResult::Ambiguous: 140 // Recover from type-hiding ambiguities by hiding the type. We'll 141 // do the lookup again when looking for an object, and we can 142 // diagnose the error then. If we don't do this, then the error 143 // about hiding the type will be immediately followed by an error 144 // that only makes sense if the identifier was treated like a type. 145 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 146 Result.suppressDiagnostics(); 147 return 0; 148 } 149 150 // Look to see if we have a type anywhere in the list of results. 151 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 152 Res != ResEnd; ++Res) { 153 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 154 if (!IIDecl || 155 (*Res)->getLocation().getRawEncoding() < 156 IIDecl->getLocation().getRawEncoding()) 157 IIDecl = *Res; 158 } 159 } 160 161 if (!IIDecl) { 162 // None of the entities we found is a type, so there is no way 163 // to even assume that the result is a type. In this case, don't 164 // complain about the ambiguity. The parser will either try to 165 // perform this lookup again (e.g., as an object name), which 166 // will produce the ambiguity, or will complain that it expected 167 // a type name. 168 Result.suppressDiagnostics(); 169 return 0; 170 } 171 172 // We found a type within the ambiguous lookup; diagnose the 173 // ambiguity and then return that type. This might be the right 174 // answer, or it might not be, but it suppresses any attempt to 175 // perform the name lookup again. 176 break; 177 178 case LookupResult::Found: 179 IIDecl = Result.getFoundDecl(); 180 break; 181 } 182 183 assert(IIDecl && "Didn't find decl"); 184 185 QualType T; 186 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 187 DiagnoseUseOfDecl(IIDecl, NameLoc); 188 189 // C++ [temp.local]p2: 190 // Within the scope of a class template specialization or 191 // partial specialization, when the injected-class-name is 192 // not followed by a <, it is equivalent to the 193 // injected-class-name followed by the template-argument s 194 // of the class template specialization or partial 195 // specialization enclosed in <>. 196 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 197 if (RD->isInjectedClassName()) 198 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 199 T = Template->getInjectedClassNameType(Context); 200 201 if (T.isNull()) 202 T = Context.getTypeDeclType(TD); 203 204 if (SS) 205 T = getQualifiedNameType(*SS, T); 206 207 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 208 T = Context.getObjCInterfaceType(IDecl); 209 } else if (UnresolvedUsingTypenameDecl *UUDecl = 210 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 211 // FIXME: preserve source structure information. 212 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 213 } else { 214 // If it's not plausibly a type, suppress diagnostics. 215 Result.suppressDiagnostics(); 216 return 0; 217 } 218 219 return T.getAsOpaquePtr(); 220} 221 222/// isTagName() - This method is called *for error recovery purposes only* 223/// to determine if the specified name is a valid tag name ("struct foo"). If 224/// so, this returns the TST for the tag corresponding to it (TST_enum, 225/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 226/// where the user forgot to specify the tag. 227DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 228 // Do a tag name lookup in this scope. 229 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 230 LookupName(R, S, false); 231 R.suppressDiagnostics(); 232 if (R.getResultKind() == LookupResult::Found) 233 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 234 switch (TD->getTagKind()) { 235 case TagDecl::TK_struct: return DeclSpec::TST_struct; 236 case TagDecl::TK_union: return DeclSpec::TST_union; 237 case TagDecl::TK_class: return DeclSpec::TST_class; 238 case TagDecl::TK_enum: return DeclSpec::TST_enum; 239 } 240 } 241 242 return DeclSpec::TST_unspecified; 243} 244 245bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 246 SourceLocation IILoc, 247 Scope *S, 248 const CXXScopeSpec *SS, 249 TypeTy *&SuggestedType) { 250 // We don't have anything to suggest (yet). 251 SuggestedType = 0; 252 253 // FIXME: Should we move the logic that tries to recover from a missing tag 254 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 255 256 if (!SS) 257 Diag(IILoc, diag::err_unknown_typename) << &II; 258 else if (DeclContext *DC = computeDeclContext(*SS, false)) 259 Diag(IILoc, diag::err_typename_nested_not_found) 260 << &II << DC << SS->getRange(); 261 else if (isDependentScopeSpecifier(*SS)) { 262 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 263 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 264 << SourceRange(SS->getRange().getBegin(), IILoc) 265 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 266 "typename "); 267 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 268 } else { 269 assert(SS && SS->isInvalid() && 270 "Invalid scope specifier has already been diagnosed"); 271 } 272 273 return true; 274} 275 276// Determines the context to return to after temporarily entering a 277// context. This depends in an unnecessarily complicated way on the 278// exact ordering of callbacks from the parser. 279DeclContext *Sema::getContainingDC(DeclContext *DC) { 280 281 // Functions defined inline within classes aren't parsed until we've 282 // finished parsing the top-level class, so the top-level class is 283 // the context we'll need to return to. 284 if (isa<FunctionDecl>(DC)) { 285 DC = DC->getLexicalParent(); 286 287 // A function not defined within a class will always return to its 288 // lexical context. 289 if (!isa<CXXRecordDecl>(DC)) 290 return DC; 291 292 // A C++ inline method/friend is parsed *after* the topmost class 293 // it was declared in is fully parsed ("complete"); the topmost 294 // class is the context we need to return to. 295 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 296 DC = RD; 297 298 // Return the declaration context of the topmost class the inline method is 299 // declared in. 300 return DC; 301 } 302 303 if (isa<ObjCMethodDecl>(DC)) 304 return Context.getTranslationUnitDecl(); 305 306 return DC->getLexicalParent(); 307} 308 309void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 310 assert(getContainingDC(DC) == CurContext && 311 "The next DeclContext should be lexically contained in the current one."); 312 CurContext = DC; 313 S->setEntity(DC); 314} 315 316void Sema::PopDeclContext() { 317 assert(CurContext && "DeclContext imbalance!"); 318 319 CurContext = getContainingDC(CurContext); 320} 321 322/// EnterDeclaratorContext - Used when we must lookup names in the context 323/// of a declarator's nested name specifier. 324void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 325 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 326 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 327 CurContext = DC; 328 assert(CurContext && "No context?"); 329 S->setEntity(CurContext); 330} 331 332void Sema::ExitDeclaratorContext(Scope *S) { 333 S->setEntity(PreDeclaratorDC); 334 PreDeclaratorDC = 0; 335 336 // Reset CurContext to the nearest enclosing context. 337 while (!S->getEntity() && S->getParent()) 338 S = S->getParent(); 339 CurContext = static_cast<DeclContext*>(S->getEntity()); 340 assert(CurContext && "No context?"); 341} 342 343/// \brief Determine whether we allow overloading of the function 344/// PrevDecl with another declaration. 345/// 346/// This routine determines whether overloading is possible, not 347/// whether some new function is actually an overload. It will return 348/// true in C++ (where we can always provide overloads) or, as an 349/// extension, in C when the previous function is already an 350/// overloaded function declaration or has the "overloadable" 351/// attribute. 352static bool AllowOverloadingOfFunction(LookupResult &Previous, 353 ASTContext &Context) { 354 if (Context.getLangOptions().CPlusPlus) 355 return true; 356 357 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 358 return true; 359 360 return (Previous.getResultKind() == LookupResult::Found 361 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 362} 363 364/// Add this decl to the scope shadowed decl chains. 365void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 366 // Move up the scope chain until we find the nearest enclosing 367 // non-transparent context. The declaration will be introduced into this 368 // scope. 369 while (S->getEntity() && 370 ((DeclContext *)S->getEntity())->isTransparentContext()) 371 S = S->getParent(); 372 373 // Add scoped declarations into their context, so that they can be 374 // found later. Declarations without a context won't be inserted 375 // into any context. 376 if (AddToContext) 377 CurContext->addDecl(D); 378 379 // Out-of-line function and variable definitions should not be pushed into 380 // scope. 381 if ((isa<FunctionTemplateDecl>(D) && 382 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 383 (isa<FunctionDecl>(D) && 384 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 385 cast<FunctionDecl>(D)->isOutOfLine())) || 386 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 387 return; 388 389 // If this replaces anything in the current scope, 390 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 391 IEnd = IdResolver.end(); 392 for (; I != IEnd; ++I) { 393 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 394 S->RemoveDecl(DeclPtrTy::make(*I)); 395 IdResolver.RemoveDecl(*I); 396 397 // Should only need to replace one decl. 398 break; 399 } 400 } 401 402 S->AddDecl(DeclPtrTy::make(D)); 403 IdResolver.AddDecl(D); 404} 405 406bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 407 return IdResolver.isDeclInScope(D, Ctx, Context, S); 408} 409 410static bool isOutOfScopePreviousDeclaration(NamedDecl *, 411 DeclContext*, 412 ASTContext&); 413 414/// Filters out lookup results that don't fall within the given scope 415/// as determined by isDeclInScope. 416static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 417 DeclContext *Ctx, Scope *S, 418 bool ConsiderLinkage) { 419 LookupResult::Filter F = R.makeFilter(); 420 while (F.hasNext()) { 421 NamedDecl *D = F.next(); 422 423 if (SemaRef.isDeclInScope(D, Ctx, S)) 424 continue; 425 426 if (ConsiderLinkage && 427 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 428 continue; 429 430 F.erase(); 431 } 432 433 F.done(); 434} 435 436static bool isUsingDecl(NamedDecl *D) { 437 return isa<UsingShadowDecl>(D) || 438 isa<UnresolvedUsingTypenameDecl>(D) || 439 isa<UnresolvedUsingValueDecl>(D); 440} 441 442/// Removes using shadow declarations from the lookup results. 443static void RemoveUsingDecls(LookupResult &R) { 444 LookupResult::Filter F = R.makeFilter(); 445 while (F.hasNext()) 446 if (isUsingDecl(F.next())) 447 F.erase(); 448 449 F.done(); 450} 451 452static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 453 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 454 return false; 455 456 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 457 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 458 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 459 if (!RD->hasTrivialConstructor()) 460 return false; 461 if (!RD->hasTrivialDestructor()) 462 return false; 463 } 464 } 465 } 466 467 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 468 !isa<ImplicitParamDecl>(D) && 469 D->getDeclContext()->isFunctionOrMethod()); 470} 471 472void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 473 if (S->decl_empty()) return; 474 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 475 "Scope shouldn't contain decls!"); 476 477 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 478 I != E; ++I) { 479 Decl *TmpD = (*I).getAs<Decl>(); 480 assert(TmpD && "This decl didn't get pushed??"); 481 482 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 483 NamedDecl *D = cast<NamedDecl>(TmpD); 484 485 if (!D->getDeclName()) continue; 486 487 // Diagnose unused variables in this scope. 488 if (ShouldDiagnoseUnusedDecl(D)) 489 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 490 491 // Remove this name from our lexical scope. 492 IdResolver.RemoveDecl(D); 493 } 494} 495 496/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 497/// return 0 if one not found. 498ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 499 // The third "scope" argument is 0 since we aren't enabling lazy built-in 500 // creation from this context. 501 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 502 503 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 504} 505 506/// getNonFieldDeclScope - Retrieves the innermost scope, starting 507/// from S, where a non-field would be declared. This routine copes 508/// with the difference between C and C++ scoping rules in structs and 509/// unions. For example, the following code is well-formed in C but 510/// ill-formed in C++: 511/// @code 512/// struct S6 { 513/// enum { BAR } e; 514/// }; 515/// 516/// void test_S6() { 517/// struct S6 a; 518/// a.e = BAR; 519/// } 520/// @endcode 521/// For the declaration of BAR, this routine will return a different 522/// scope. The scope S will be the scope of the unnamed enumeration 523/// within S6. In C++, this routine will return the scope associated 524/// with S6, because the enumeration's scope is a transparent 525/// context but structures can contain non-field names. In C, this 526/// routine will return the translation unit scope, since the 527/// enumeration's scope is a transparent context and structures cannot 528/// contain non-field names. 529Scope *Sema::getNonFieldDeclScope(Scope *S) { 530 while (((S->getFlags() & Scope::DeclScope) == 0) || 531 (S->getEntity() && 532 ((DeclContext *)S->getEntity())->isTransparentContext()) || 533 (S->isClassScope() && !getLangOptions().CPlusPlus)) 534 S = S->getParent(); 535 return S; 536} 537 538void Sema::InitBuiltinVaListType() { 539 if (!Context.getBuiltinVaListType().isNull()) 540 return; 541 542 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 543 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 544 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 545 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 546} 547 548/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 549/// file scope. lazily create a decl for it. ForRedeclaration is true 550/// if we're creating this built-in in anticipation of redeclaring the 551/// built-in. 552NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 553 Scope *S, bool ForRedeclaration, 554 SourceLocation Loc) { 555 Builtin::ID BID = (Builtin::ID)bid; 556 557 if (Context.BuiltinInfo.hasVAListUse(BID)) 558 InitBuiltinVaListType(); 559 560 ASTContext::GetBuiltinTypeError Error; 561 QualType R = Context.GetBuiltinType(BID, Error); 562 switch (Error) { 563 case ASTContext::GE_None: 564 // Okay 565 break; 566 567 case ASTContext::GE_Missing_stdio: 568 if (ForRedeclaration) 569 Diag(Loc, diag::err_implicit_decl_requires_stdio) 570 << Context.BuiltinInfo.GetName(BID); 571 return 0; 572 573 case ASTContext::GE_Missing_setjmp: 574 if (ForRedeclaration) 575 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 576 << Context.BuiltinInfo.GetName(BID); 577 return 0; 578 } 579 580 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 581 Diag(Loc, diag::ext_implicit_lib_function_decl) 582 << Context.BuiltinInfo.GetName(BID) 583 << R; 584 if (Context.BuiltinInfo.getHeaderName(BID) && 585 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 586 != Diagnostic::Ignored) 587 Diag(Loc, diag::note_please_include_header) 588 << Context.BuiltinInfo.getHeaderName(BID) 589 << Context.BuiltinInfo.GetName(BID); 590 } 591 592 FunctionDecl *New = FunctionDecl::Create(Context, 593 Context.getTranslationUnitDecl(), 594 Loc, II, R, /*TInfo=*/0, 595 FunctionDecl::Extern, false, 596 /*hasPrototype=*/true); 597 New->setImplicit(); 598 599 // Create Decl objects for each parameter, adding them to the 600 // FunctionDecl. 601 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 602 llvm::SmallVector<ParmVarDecl*, 16> Params; 603 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 604 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 605 FT->getArgType(i), /*TInfo=*/0, 606 VarDecl::None, 0)); 607 New->setParams(Context, Params.data(), Params.size()); 608 } 609 610 AddKnownFunctionAttributes(New); 611 612 // TUScope is the translation-unit scope to insert this function into. 613 // FIXME: This is hideous. We need to teach PushOnScopeChains to 614 // relate Scopes to DeclContexts, and probably eliminate CurContext 615 // entirely, but we're not there yet. 616 DeclContext *SavedContext = CurContext; 617 CurContext = Context.getTranslationUnitDecl(); 618 PushOnScopeChains(New, TUScope); 619 CurContext = SavedContext; 620 return New; 621} 622 623/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 624/// same name and scope as a previous declaration 'Old'. Figure out 625/// how to resolve this situation, merging decls or emitting 626/// diagnostics as appropriate. If there was an error, set New to be invalid. 627/// 628void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 629 // If the new decl is known invalid already, don't bother doing any 630 // merging checks. 631 if (New->isInvalidDecl()) return; 632 633 // Allow multiple definitions for ObjC built-in typedefs. 634 // FIXME: Verify the underlying types are equivalent! 635 if (getLangOptions().ObjC1) { 636 const IdentifierInfo *TypeID = New->getIdentifier(); 637 switch (TypeID->getLength()) { 638 default: break; 639 case 2: 640 if (!TypeID->isStr("id")) 641 break; 642 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 643 // Install the built-in type for 'id', ignoring the current definition. 644 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 645 return; 646 case 5: 647 if (!TypeID->isStr("Class")) 648 break; 649 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 650 // Install the built-in type for 'Class', ignoring the current definition. 651 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 652 return; 653 case 3: 654 if (!TypeID->isStr("SEL")) 655 break; 656 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 657 // Install the built-in type for 'SEL', ignoring the current definition. 658 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 659 return; 660 case 8: 661 if (!TypeID->isStr("Protocol")) 662 break; 663 Context.setObjCProtoType(New->getUnderlyingType()); 664 return; 665 } 666 // Fall through - the typedef name was not a builtin type. 667 } 668 669 // Verify the old decl was also a type. 670 TypeDecl *Old = 0; 671 if (!OldDecls.isSingleResult() || 672 !(Old = dyn_cast<TypeDecl>(OldDecls.getFoundDecl()))) { 673 Diag(New->getLocation(), diag::err_redefinition_different_kind) 674 << New->getDeclName(); 675 676 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 677 if (OldD->getLocation().isValid()) 678 Diag(OldD->getLocation(), diag::note_previous_definition); 679 680 return New->setInvalidDecl(); 681 } 682 683 // If the old declaration is invalid, just give up here. 684 if (Old->isInvalidDecl()) 685 return New->setInvalidDecl(); 686 687 // Determine the "old" type we'll use for checking and diagnostics. 688 QualType OldType; 689 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 690 OldType = OldTypedef->getUnderlyingType(); 691 else 692 OldType = Context.getTypeDeclType(Old); 693 694 // If the typedef types are not identical, reject them in all languages and 695 // with any extensions enabled. 696 697 if (OldType != New->getUnderlyingType() && 698 Context.getCanonicalType(OldType) != 699 Context.getCanonicalType(New->getUnderlyingType())) { 700 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 701 << New->getUnderlyingType() << OldType; 702 if (Old->getLocation().isValid()) 703 Diag(Old->getLocation(), diag::note_previous_definition); 704 return New->setInvalidDecl(); 705 } 706 707 if (getLangOptions().Microsoft) 708 return; 709 710 // C++ [dcl.typedef]p2: 711 // In a given non-class scope, a typedef specifier can be used to 712 // redefine the name of any type declared in that scope to refer 713 // to the type to which it already refers. 714 if (getLangOptions().CPlusPlus) { 715 if (!isa<CXXRecordDecl>(CurContext)) 716 return; 717 Diag(New->getLocation(), diag::err_redefinition) 718 << New->getDeclName(); 719 Diag(Old->getLocation(), diag::note_previous_definition); 720 return New->setInvalidDecl(); 721 } 722 723 // If we have a redefinition of a typedef in C, emit a warning. This warning 724 // is normally mapped to an error, but can be controlled with 725 // -Wtypedef-redefinition. If either the original or the redefinition is 726 // in a system header, don't emit this for compatibility with GCC. 727 if (PP.getDiagnostics().getSuppressSystemWarnings() && 728 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 729 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 730 return; 731 732 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 733 << New->getDeclName(); 734 Diag(Old->getLocation(), diag::note_previous_definition); 735 return; 736} 737 738/// DeclhasAttr - returns true if decl Declaration already has the target 739/// attribute. 740static bool 741DeclHasAttr(const Decl *decl, const Attr *target) { 742 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 743 if (attr->getKind() == target->getKind()) 744 return true; 745 746 return false; 747} 748 749/// MergeAttributes - append attributes from the Old decl to the New one. 750static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 751 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 752 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 753 Attr *NewAttr = attr->clone(C); 754 NewAttr->setInherited(true); 755 New->addAttr(NewAttr); 756 } 757 } 758} 759 760/// Used in MergeFunctionDecl to keep track of function parameters in 761/// C. 762struct GNUCompatibleParamWarning { 763 ParmVarDecl *OldParm; 764 ParmVarDecl *NewParm; 765 QualType PromotedType; 766}; 767 768 769/// getSpecialMember - get the special member enum for a method. 770static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 771 const CXXMethodDecl *MD) { 772 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 773 if (Ctor->isDefaultConstructor()) 774 return Sema::CXXDefaultConstructor; 775 if (Ctor->isCopyConstructor(Ctx)) 776 return Sema::CXXCopyConstructor; 777 } 778 779 if (isa<CXXDestructorDecl>(MD)) 780 return Sema::CXXDestructor; 781 782 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 783 return Sema::CXXCopyAssignment; 784} 785 786/// MergeFunctionDecl - We just parsed a function 'New' from 787/// declarator D which has the same name and scope as a previous 788/// declaration 'Old'. Figure out how to resolve this situation, 789/// merging decls or emitting diagnostics as appropriate. 790/// 791/// In C++, New and Old must be declarations that are not 792/// overloaded. Use IsOverload to determine whether New and Old are 793/// overloaded, and to select the Old declaration that New should be 794/// merged with. 795/// 796/// Returns true if there was an error, false otherwise. 797bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 798 // Verify the old decl was also a function. 799 FunctionDecl *Old = 0; 800 if (FunctionTemplateDecl *OldFunctionTemplate 801 = dyn_cast<FunctionTemplateDecl>(OldD)) 802 Old = OldFunctionTemplate->getTemplatedDecl(); 803 else 804 Old = dyn_cast<FunctionDecl>(OldD); 805 if (!Old) { 806 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 807 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 808 Diag(Shadow->getTargetDecl()->getLocation(), 809 diag::note_using_decl_target); 810 Diag(Shadow->getUsingDecl()->getLocation(), 811 diag::note_using_decl) << 0; 812 return true; 813 } 814 815 Diag(New->getLocation(), diag::err_redefinition_different_kind) 816 << New->getDeclName(); 817 Diag(OldD->getLocation(), diag::note_previous_definition); 818 return true; 819 } 820 821 // Determine whether the previous declaration was a definition, 822 // implicit declaration, or a declaration. 823 diag::kind PrevDiag; 824 if (Old->isThisDeclarationADefinition()) 825 PrevDiag = diag::note_previous_definition; 826 else if (Old->isImplicit()) 827 PrevDiag = diag::note_previous_implicit_declaration; 828 else 829 PrevDiag = diag::note_previous_declaration; 830 831 QualType OldQType = Context.getCanonicalType(Old->getType()); 832 QualType NewQType = Context.getCanonicalType(New->getType()); 833 834 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 835 New->getStorageClass() == FunctionDecl::Static && 836 Old->getStorageClass() != FunctionDecl::Static) { 837 Diag(New->getLocation(), diag::err_static_non_static) 838 << New; 839 Diag(Old->getLocation(), PrevDiag); 840 return true; 841 } 842 843 if (getLangOptions().CPlusPlus) { 844 // (C++98 13.1p2): 845 // Certain function declarations cannot be overloaded: 846 // -- Function declarations that differ only in the return type 847 // cannot be overloaded. 848 QualType OldReturnType 849 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 850 QualType NewReturnType 851 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 852 if (OldReturnType != NewReturnType) { 853 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 854 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 855 return true; 856 } 857 858 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 859 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 860 if (OldMethod && NewMethod) { 861 if (!NewMethod->getFriendObjectKind() && 862 NewMethod->getLexicalDeclContext()->isRecord()) { 863 // -- Member function declarations with the same name and the 864 // same parameter types cannot be overloaded if any of them 865 // is a static member function declaration. 866 if (OldMethod->isStatic() || NewMethod->isStatic()) { 867 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 868 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 869 return true; 870 } 871 872 // C++ [class.mem]p1: 873 // [...] A member shall not be declared twice in the 874 // member-specification, except that a nested class or member 875 // class template can be declared and then later defined. 876 unsigned NewDiag; 877 if (isa<CXXConstructorDecl>(OldMethod)) 878 NewDiag = diag::err_constructor_redeclared; 879 else if (isa<CXXDestructorDecl>(NewMethod)) 880 NewDiag = diag::err_destructor_redeclared; 881 else if (isa<CXXConversionDecl>(NewMethod)) 882 NewDiag = diag::err_conv_function_redeclared; 883 else 884 NewDiag = diag::err_member_redeclared; 885 886 Diag(New->getLocation(), NewDiag); 887 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 888 } else { 889 if (OldMethod->isImplicit()) { 890 Diag(NewMethod->getLocation(), 891 diag::err_definition_of_implicitly_declared_member) 892 << New << getSpecialMember(Context, OldMethod); 893 894 Diag(OldMethod->getLocation(), 895 diag::note_previous_implicit_declaration); 896 return true; 897 } 898 } 899 } 900 901 // (C++98 8.3.5p3): 902 // All declarations for a function shall agree exactly in both the 903 // return type and the parameter-type-list. 904 if (OldQType == NewQType) 905 return MergeCompatibleFunctionDecls(New, Old); 906 907 // Fall through for conflicting redeclarations and redefinitions. 908 } 909 910 // C: Function types need to be compatible, not identical. This handles 911 // duplicate function decls like "void f(int); void f(enum X);" properly. 912 if (!getLangOptions().CPlusPlus && 913 Context.typesAreCompatible(OldQType, NewQType)) { 914 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 915 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 916 const FunctionProtoType *OldProto = 0; 917 if (isa<FunctionNoProtoType>(NewFuncType) && 918 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 919 // The old declaration provided a function prototype, but the 920 // new declaration does not. Merge in the prototype. 921 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 922 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 923 OldProto->arg_type_end()); 924 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 925 ParamTypes.data(), ParamTypes.size(), 926 OldProto->isVariadic(), 927 OldProto->getTypeQuals()); 928 New->setType(NewQType); 929 New->setHasInheritedPrototype(); 930 931 // Synthesize a parameter for each argument type. 932 llvm::SmallVector<ParmVarDecl*, 16> Params; 933 for (FunctionProtoType::arg_type_iterator 934 ParamType = OldProto->arg_type_begin(), 935 ParamEnd = OldProto->arg_type_end(); 936 ParamType != ParamEnd; ++ParamType) { 937 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 938 SourceLocation(), 0, 939 *ParamType, /*TInfo=*/0, 940 VarDecl::None, 0); 941 Param->setImplicit(); 942 Params.push_back(Param); 943 } 944 945 New->setParams(Context, Params.data(), Params.size()); 946 } 947 948 return MergeCompatibleFunctionDecls(New, Old); 949 } 950 951 // GNU C permits a K&R definition to follow a prototype declaration 952 // if the declared types of the parameters in the K&R definition 953 // match the types in the prototype declaration, even when the 954 // promoted types of the parameters from the K&R definition differ 955 // from the types in the prototype. GCC then keeps the types from 956 // the prototype. 957 // 958 // If a variadic prototype is followed by a non-variadic K&R definition, 959 // the K&R definition becomes variadic. This is sort of an edge case, but 960 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 961 // C99 6.9.1p8. 962 if (!getLangOptions().CPlusPlus && 963 Old->hasPrototype() && !New->hasPrototype() && 964 New->getType()->getAs<FunctionProtoType>() && 965 Old->getNumParams() == New->getNumParams()) { 966 llvm::SmallVector<QualType, 16> ArgTypes; 967 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 968 const FunctionProtoType *OldProto 969 = Old->getType()->getAs<FunctionProtoType>(); 970 const FunctionProtoType *NewProto 971 = New->getType()->getAs<FunctionProtoType>(); 972 973 // Determine whether this is the GNU C extension. 974 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 975 NewProto->getResultType()); 976 bool LooseCompatible = !MergedReturn.isNull(); 977 for (unsigned Idx = 0, End = Old->getNumParams(); 978 LooseCompatible && Idx != End; ++Idx) { 979 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 980 ParmVarDecl *NewParm = New->getParamDecl(Idx); 981 if (Context.typesAreCompatible(OldParm->getType(), 982 NewProto->getArgType(Idx))) { 983 ArgTypes.push_back(NewParm->getType()); 984 } else if (Context.typesAreCompatible(OldParm->getType(), 985 NewParm->getType())) { 986 GNUCompatibleParamWarning Warn 987 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 988 Warnings.push_back(Warn); 989 ArgTypes.push_back(NewParm->getType()); 990 } else 991 LooseCompatible = false; 992 } 993 994 if (LooseCompatible) { 995 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 996 Diag(Warnings[Warn].NewParm->getLocation(), 997 diag::ext_param_promoted_not_compatible_with_prototype) 998 << Warnings[Warn].PromotedType 999 << Warnings[Warn].OldParm->getType(); 1000 Diag(Warnings[Warn].OldParm->getLocation(), 1001 diag::note_previous_declaration); 1002 } 1003 1004 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1005 ArgTypes.size(), 1006 OldProto->isVariadic(), 0)); 1007 return MergeCompatibleFunctionDecls(New, Old); 1008 } 1009 1010 // Fall through to diagnose conflicting types. 1011 } 1012 1013 // A function that has already been declared has been redeclared or defined 1014 // with a different type- show appropriate diagnostic 1015 if (unsigned BuiltinID = Old->getBuiltinID()) { 1016 // The user has declared a builtin function with an incompatible 1017 // signature. 1018 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1019 // The function the user is redeclaring is a library-defined 1020 // function like 'malloc' or 'printf'. Warn about the 1021 // redeclaration, then pretend that we don't know about this 1022 // library built-in. 1023 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1024 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1025 << Old << Old->getType(); 1026 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1027 Old->setInvalidDecl(); 1028 return false; 1029 } 1030 1031 PrevDiag = diag::note_previous_builtin_declaration; 1032 } 1033 1034 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1035 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1036 return true; 1037} 1038 1039/// \brief Completes the merge of two function declarations that are 1040/// known to be compatible. 1041/// 1042/// This routine handles the merging of attributes and other 1043/// properties of function declarations form the old declaration to 1044/// the new declaration, once we know that New is in fact a 1045/// redeclaration of Old. 1046/// 1047/// \returns false 1048bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1049 // Merge the attributes 1050 MergeAttributes(New, Old, Context); 1051 1052 // Merge the storage class. 1053 if (Old->getStorageClass() != FunctionDecl::Extern && 1054 Old->getStorageClass() != FunctionDecl::None) 1055 New->setStorageClass(Old->getStorageClass()); 1056 1057 // Merge "pure" flag. 1058 if (Old->isPure()) 1059 New->setPure(); 1060 1061 // Merge the "deleted" flag. 1062 if (Old->isDeleted()) 1063 New->setDeleted(); 1064 1065 if (getLangOptions().CPlusPlus) 1066 return MergeCXXFunctionDecl(New, Old); 1067 1068 return false; 1069} 1070 1071/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1072/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1073/// situation, merging decls or emitting diagnostics as appropriate. 1074/// 1075/// Tentative definition rules (C99 6.9.2p2) are checked by 1076/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1077/// definitions here, since the initializer hasn't been attached. 1078/// 1079void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1080 // If the new decl is already invalid, don't do any other checking. 1081 if (New->isInvalidDecl()) 1082 return; 1083 1084 // Verify the old decl was also a variable. 1085 VarDecl *Old = 0; 1086 if (!Previous.isSingleResult() || 1087 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1088 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1089 << New->getDeclName(); 1090 Diag(Previous.getRepresentativeDecl()->getLocation(), 1091 diag::note_previous_definition); 1092 return New->setInvalidDecl(); 1093 } 1094 1095 MergeAttributes(New, Old, Context); 1096 1097 // Merge the types 1098 QualType MergedT; 1099 if (getLangOptions().CPlusPlus) { 1100 if (Context.hasSameType(New->getType(), Old->getType())) 1101 MergedT = New->getType(); 1102 // C++ [basic.link]p10: 1103 // [...] the types specified by all declarations referring to a given 1104 // object or function shall be identical, except that declarations for an 1105 // array object can specify array types that differ by the presence or 1106 // absence of a major array bound (8.3.4). 1107 else if (Old->getType()->isIncompleteArrayType() && 1108 New->getType()->isArrayType()) { 1109 CanQual<ArrayType> OldArray 1110 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1111 CanQual<ArrayType> NewArray 1112 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1113 if (OldArray->getElementType() == NewArray->getElementType()) 1114 MergedT = New->getType(); 1115 } else if (Old->getType()->isArrayType() && 1116 New->getType()->isIncompleteArrayType()) { 1117 CanQual<ArrayType> OldArray 1118 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1119 CanQual<ArrayType> NewArray 1120 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1121 if (OldArray->getElementType() == NewArray->getElementType()) 1122 MergedT = Old->getType(); 1123 } 1124 } else { 1125 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1126 } 1127 if (MergedT.isNull()) { 1128 Diag(New->getLocation(), diag::err_redefinition_different_type) 1129 << New->getDeclName(); 1130 Diag(Old->getLocation(), diag::note_previous_definition); 1131 return New->setInvalidDecl(); 1132 } 1133 New->setType(MergedT); 1134 1135 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1136 if (New->getStorageClass() == VarDecl::Static && 1137 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1138 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1139 Diag(Old->getLocation(), diag::note_previous_definition); 1140 return New->setInvalidDecl(); 1141 } 1142 // C99 6.2.2p4: 1143 // For an identifier declared with the storage-class specifier 1144 // extern in a scope in which a prior declaration of that 1145 // identifier is visible,23) if the prior declaration specifies 1146 // internal or external linkage, the linkage of the identifier at 1147 // the later declaration is the same as the linkage specified at 1148 // the prior declaration. If no prior declaration is visible, or 1149 // if the prior declaration specifies no linkage, then the 1150 // identifier has external linkage. 1151 if (New->hasExternalStorage() && Old->hasLinkage()) 1152 /* Okay */; 1153 else if (New->getStorageClass() != VarDecl::Static && 1154 Old->getStorageClass() == VarDecl::Static) { 1155 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1156 Diag(Old->getLocation(), diag::note_previous_definition); 1157 return New->setInvalidDecl(); 1158 } 1159 1160 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1161 1162 // FIXME: The test for external storage here seems wrong? We still 1163 // need to check for mismatches. 1164 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1165 // Don't complain about out-of-line definitions of static members. 1166 !(Old->getLexicalDeclContext()->isRecord() && 1167 !New->getLexicalDeclContext()->isRecord())) { 1168 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1169 Diag(Old->getLocation(), diag::note_previous_definition); 1170 return New->setInvalidDecl(); 1171 } 1172 1173 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1174 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1175 Diag(Old->getLocation(), diag::note_previous_definition); 1176 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1177 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1178 Diag(Old->getLocation(), diag::note_previous_definition); 1179 } 1180 1181 // Keep a chain of previous declarations. 1182 New->setPreviousDeclaration(Old); 1183} 1184 1185/// CheckFallThrough - Check that we don't fall off the end of a 1186/// Statement that should return a value. 1187/// 1188/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1189/// MaybeFallThrough iff we might or might not fall off the end, 1190/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1191/// return. We assume NeverFallThrough iff we never fall off the end of the 1192/// statement but we may return. We assume that functions not marked noreturn 1193/// will return. 1194Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1195 // FIXME: Eventually share this CFG object when we have other warnings based 1196 // of the CFG. This can be done using AnalysisContext. 1197 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1198 1199 // FIXME: They should never return 0, fix that, delete this code. 1200 if (cfg == 0) 1201 // FIXME: This should be NeverFallThrough 1202 return NeverFallThroughOrReturn; 1203 // The CFG leaves in dead things, and we don't want to dead code paths to 1204 // confuse us, so we mark all live things first. 1205 std::queue<CFGBlock*> workq; 1206 llvm::BitVector live(cfg->getNumBlockIDs()); 1207 // Prep work queue 1208 workq.push(&cfg->getEntry()); 1209 // Solve 1210 while (!workq.empty()) { 1211 CFGBlock *item = workq.front(); 1212 workq.pop(); 1213 live.set(item->getBlockID()); 1214 for (CFGBlock::succ_iterator I=item->succ_begin(), 1215 E=item->succ_end(); 1216 I != E; 1217 ++I) { 1218 if ((*I) && !live[(*I)->getBlockID()]) { 1219 live.set((*I)->getBlockID()); 1220 workq.push(*I); 1221 } 1222 } 1223 } 1224 1225 // Now we know what is live, we check the live precessors of the exit block 1226 // and look for fall through paths, being careful to ignore normal returns, 1227 // and exceptional paths. 1228 bool HasLiveReturn = false; 1229 bool HasFakeEdge = false; 1230 bool HasPlainEdge = false; 1231 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1232 E = cfg->getExit().pred_end(); 1233 I != E; 1234 ++I) { 1235 CFGBlock& B = **I; 1236 if (!live[B.getBlockID()]) 1237 continue; 1238 if (B.size() == 0) { 1239 // A labeled empty statement, or the entry block... 1240 HasPlainEdge = true; 1241 continue; 1242 } 1243 Stmt *S = B[B.size()-1]; 1244 if (isa<ReturnStmt>(S)) { 1245 HasLiveReturn = true; 1246 continue; 1247 } 1248 if (isa<ObjCAtThrowStmt>(S)) { 1249 HasFakeEdge = true; 1250 continue; 1251 } 1252 if (isa<CXXThrowExpr>(S)) { 1253 HasFakeEdge = true; 1254 continue; 1255 } 1256 bool NoReturnEdge = false; 1257 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1258 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1259 if (CEE->getType().getNoReturnAttr()) { 1260 NoReturnEdge = true; 1261 HasFakeEdge = true; 1262 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1263 ValueDecl *VD = DRE->getDecl(); 1264 if (VD->hasAttr<NoReturnAttr>()) { 1265 NoReturnEdge = true; 1266 HasFakeEdge = true; 1267 } 1268 } 1269 } 1270 // FIXME: Add noreturn message sends. 1271 if (NoReturnEdge == false) 1272 HasPlainEdge = true; 1273 } 1274 if (!HasPlainEdge) { 1275 if (HasLiveReturn) 1276 return NeverFallThrough; 1277 return NeverFallThroughOrReturn; 1278 } 1279 if (HasFakeEdge || HasLiveReturn) 1280 return MaybeFallThrough; 1281 // This says AlwaysFallThrough for calls to functions that are not marked 1282 // noreturn, that don't return. If people would like this warning to be more 1283 // accurate, such functions should be marked as noreturn. 1284 return AlwaysFallThrough; 1285} 1286 1287/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1288/// function that should return a value. Check that we don't fall off the end 1289/// of a noreturn function. We assume that functions and blocks not marked 1290/// noreturn will return. 1291void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1292 // FIXME: Would be nice if we had a better way to control cascading errors, 1293 // but for now, avoid them. The problem is that when Parse sees: 1294 // int foo() { return a; } 1295 // The return is eaten and the Sema code sees just: 1296 // int foo() { } 1297 // which this code would then warn about. 1298 if (getDiagnostics().hasErrorOccurred()) 1299 return; 1300 1301 bool ReturnsVoid = false; 1302 bool HasNoReturn = false; 1303 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1304 // If the result type of the function is a dependent type, we don't know 1305 // whether it will be void or not, so don't 1306 if (FD->getResultType()->isDependentType()) 1307 return; 1308 if (FD->getResultType()->isVoidType()) 1309 ReturnsVoid = true; 1310 if (FD->hasAttr<NoReturnAttr>()) 1311 HasNoReturn = true; 1312 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1313 if (MD->getResultType()->isVoidType()) 1314 ReturnsVoid = true; 1315 if (MD->hasAttr<NoReturnAttr>()) 1316 HasNoReturn = true; 1317 } 1318 1319 // Short circuit for compilation speed. 1320 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1321 == Diagnostic::Ignored || ReturnsVoid) 1322 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1323 == Diagnostic::Ignored || !HasNoReturn) 1324 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1325 == Diagnostic::Ignored || !ReturnsVoid)) 1326 return; 1327 // FIXME: Function try block 1328 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1329 switch (CheckFallThrough(Body)) { 1330 case MaybeFallThrough: 1331 if (HasNoReturn) 1332 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1333 else if (!ReturnsVoid) 1334 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1335 break; 1336 case AlwaysFallThrough: 1337 if (HasNoReturn) 1338 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1339 else if (!ReturnsVoid) 1340 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1341 break; 1342 case NeverFallThroughOrReturn: 1343 if (ReturnsVoid && !HasNoReturn) 1344 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1345 break; 1346 case NeverFallThrough: 1347 break; 1348 } 1349 } 1350} 1351 1352/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1353/// that should return a value. Check that we don't fall off the end of a 1354/// noreturn block. We assume that functions and blocks not marked noreturn 1355/// will return. 1356void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1357 // FIXME: Would be nice if we had a better way to control cascading errors, 1358 // but for now, avoid them. The problem is that when Parse sees: 1359 // int foo() { return a; } 1360 // The return is eaten and the Sema code sees just: 1361 // int foo() { } 1362 // which this code would then warn about. 1363 if (getDiagnostics().hasErrorOccurred()) 1364 return; 1365 bool ReturnsVoid = false; 1366 bool HasNoReturn = false; 1367 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1368 if (FT->getResultType()->isVoidType()) 1369 ReturnsVoid = true; 1370 if (FT->getNoReturnAttr()) 1371 HasNoReturn = true; 1372 } 1373 1374 // Short circuit for compilation speed. 1375 if (ReturnsVoid 1376 && !HasNoReturn 1377 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1378 == Diagnostic::Ignored || !ReturnsVoid)) 1379 return; 1380 // FIXME: Funtion try block 1381 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1382 switch (CheckFallThrough(Body)) { 1383 case MaybeFallThrough: 1384 if (HasNoReturn) 1385 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1386 else if (!ReturnsVoid) 1387 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1388 break; 1389 case AlwaysFallThrough: 1390 if (HasNoReturn) 1391 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1392 else if (!ReturnsVoid) 1393 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1394 break; 1395 case NeverFallThroughOrReturn: 1396 if (ReturnsVoid) 1397 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1398 break; 1399 case NeverFallThrough: 1400 break; 1401 } 1402 } 1403} 1404 1405/// CheckParmsForFunctionDef - Check that the parameters of the given 1406/// function are appropriate for the definition of a function. This 1407/// takes care of any checks that cannot be performed on the 1408/// declaration itself, e.g., that the types of each of the function 1409/// parameters are complete. 1410bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1411 bool HasInvalidParm = false; 1412 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1413 ParmVarDecl *Param = FD->getParamDecl(p); 1414 1415 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1416 // function declarator that is part of a function definition of 1417 // that function shall not have incomplete type. 1418 // 1419 // This is also C++ [dcl.fct]p6. 1420 if (!Param->isInvalidDecl() && 1421 RequireCompleteType(Param->getLocation(), Param->getType(), 1422 diag::err_typecheck_decl_incomplete_type)) { 1423 Param->setInvalidDecl(); 1424 HasInvalidParm = true; 1425 } 1426 1427 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1428 // declaration of each parameter shall include an identifier. 1429 if (Param->getIdentifier() == 0 && 1430 !Param->isImplicit() && 1431 !getLangOptions().CPlusPlus) 1432 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1433 } 1434 1435 return HasInvalidParm; 1436} 1437 1438/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1439/// no declarator (e.g. "struct foo;") is parsed. 1440Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1441 // FIXME: Error on auto/register at file scope 1442 // FIXME: Error on inline/virtual/explicit 1443 // FIXME: Warn on useless __thread 1444 // FIXME: Warn on useless const/volatile 1445 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1446 // FIXME: Warn on useless attributes 1447 Decl *TagD = 0; 1448 TagDecl *Tag = 0; 1449 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1450 DS.getTypeSpecType() == DeclSpec::TST_struct || 1451 DS.getTypeSpecType() == DeclSpec::TST_union || 1452 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1453 TagD = static_cast<Decl *>(DS.getTypeRep()); 1454 1455 if (!TagD) // We probably had an error 1456 return DeclPtrTy(); 1457 1458 // Note that the above type specs guarantee that the 1459 // type rep is a Decl, whereas in many of the others 1460 // it's a Type. 1461 Tag = dyn_cast<TagDecl>(TagD); 1462 } 1463 1464 if (unsigned TypeQuals = DS.getTypeQualifiers()) { 1465 // Enforce C99 6.7.3p2: "Types other than pointer types derived from object 1466 // or incomplete types shall not be restrict-qualified." 1467 if (TypeQuals & DeclSpec::TQ_restrict) 1468 Diag(DS.getRestrictSpecLoc(), 1469 diag::err_typecheck_invalid_restrict_not_pointer_noarg) 1470 << DS.getSourceRange(); 1471 } 1472 1473 if (DS.isFriendSpecified()) { 1474 // If we're dealing with a class template decl, assume that the 1475 // template routines are handling it. 1476 if (TagD && isa<ClassTemplateDecl>(TagD)) 1477 return DeclPtrTy(); 1478 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1479 } 1480 1481 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1482 // If there are attributes in the DeclSpec, apply them to the record. 1483 if (const AttributeList *AL = DS.getAttributes()) 1484 ProcessDeclAttributeList(S, Record, AL); 1485 1486 if (!Record->getDeclName() && Record->isDefinition() && 1487 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1488 if (getLangOptions().CPlusPlus || 1489 Record->getDeclContext()->isRecord()) 1490 return BuildAnonymousStructOrUnion(S, DS, Record); 1491 1492 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1493 << DS.getSourceRange(); 1494 } 1495 1496 // Microsoft allows unnamed struct/union fields. Don't complain 1497 // about them. 1498 // FIXME: Should we support Microsoft's extensions in this area? 1499 if (Record->getDeclName() && getLangOptions().Microsoft) 1500 return DeclPtrTy::make(Tag); 1501 } 1502 1503 if (!DS.isMissingDeclaratorOk() && 1504 DS.getTypeSpecType() != DeclSpec::TST_error) { 1505 // Warn about typedefs of enums without names, since this is an 1506 // extension in both Microsoft an GNU. 1507 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1508 Tag && isa<EnumDecl>(Tag)) { 1509 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1510 << DS.getSourceRange(); 1511 return DeclPtrTy::make(Tag); 1512 } 1513 1514 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1515 << DS.getSourceRange(); 1516 return DeclPtrTy(); 1517 } 1518 1519 return DeclPtrTy::make(Tag); 1520} 1521 1522/// We are trying to inject an anonymous member into the given scope; 1523/// check if there's an existing declaration that can't be overloaded. 1524/// 1525/// \return true if this is a forbidden redeclaration 1526static bool CheckAnonMemberRedeclaration(Sema &SemaRef, 1527 Scope *S, 1528 DeclarationName Name, 1529 SourceLocation NameLoc, 1530 unsigned diagnostic) { 1531 LookupResult R(SemaRef, Name, NameLoc, Sema::LookupMemberName, 1532 Sema::ForRedeclaration); 1533 if (!SemaRef.LookupName(R, S)) return false; 1534 1535 if (R.getAsSingle<TagDecl>()) 1536 return false; 1537 1538 // Pick a representative declaration. 1539 NamedDecl *PrevDecl = R.getRepresentativeDecl()->getUnderlyingDecl(); 1540 1541 SemaRef.Diag(NameLoc, diagnostic) << Name; 1542 SemaRef.Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1543 1544 return true; 1545} 1546 1547/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1548/// anonymous struct or union AnonRecord into the owning context Owner 1549/// and scope S. This routine will be invoked just after we realize 1550/// that an unnamed union or struct is actually an anonymous union or 1551/// struct, e.g., 1552/// 1553/// @code 1554/// union { 1555/// int i; 1556/// float f; 1557/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1558/// // f into the surrounding scope.x 1559/// @endcode 1560/// 1561/// This routine is recursive, injecting the names of nested anonymous 1562/// structs/unions into the owning context and scope as well. 1563bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1564 RecordDecl *AnonRecord) { 1565 unsigned diagKind 1566 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1567 : diag::err_anonymous_struct_member_redecl; 1568 1569 bool Invalid = false; 1570 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1571 FEnd = AnonRecord->field_end(); 1572 F != FEnd; ++F) { 1573 if ((*F)->getDeclName()) { 1574 if (CheckAnonMemberRedeclaration(*this, S, (*F)->getDeclName(), 1575 (*F)->getLocation(), diagKind)) { 1576 // C++ [class.union]p2: 1577 // The names of the members of an anonymous union shall be 1578 // distinct from the names of any other entity in the 1579 // scope in which the anonymous union is declared. 1580 Invalid = true; 1581 } else { 1582 // C++ [class.union]p2: 1583 // For the purpose of name lookup, after the anonymous union 1584 // definition, the members of the anonymous union are 1585 // considered to have been defined in the scope in which the 1586 // anonymous union is declared. 1587 Owner->makeDeclVisibleInContext(*F); 1588 S->AddDecl(DeclPtrTy::make(*F)); 1589 IdResolver.AddDecl(*F); 1590 } 1591 } else if (const RecordType *InnerRecordType 1592 = (*F)->getType()->getAs<RecordType>()) { 1593 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1594 if (InnerRecord->isAnonymousStructOrUnion()) 1595 Invalid = Invalid || 1596 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1597 } 1598 } 1599 1600 return Invalid; 1601} 1602 1603/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1604/// anonymous structure or union. Anonymous unions are a C++ feature 1605/// (C++ [class.union]) and a GNU C extension; anonymous structures 1606/// are a GNU C and GNU C++ extension. 1607Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1608 RecordDecl *Record) { 1609 DeclContext *Owner = Record->getDeclContext(); 1610 1611 // Diagnose whether this anonymous struct/union is an extension. 1612 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1613 Diag(Record->getLocation(), diag::ext_anonymous_union); 1614 else if (!Record->isUnion()) 1615 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1616 1617 // C and C++ require different kinds of checks for anonymous 1618 // structs/unions. 1619 bool Invalid = false; 1620 if (getLangOptions().CPlusPlus) { 1621 const char* PrevSpec = 0; 1622 unsigned DiagID; 1623 // C++ [class.union]p3: 1624 // Anonymous unions declared in a named namespace or in the 1625 // global namespace shall be declared static. 1626 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1627 (isa<TranslationUnitDecl>(Owner) || 1628 (isa<NamespaceDecl>(Owner) && 1629 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1630 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1631 Invalid = true; 1632 1633 // Recover by adding 'static'. 1634 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1635 PrevSpec, DiagID); 1636 } 1637 // C++ [class.union]p3: 1638 // A storage class is not allowed in a declaration of an 1639 // anonymous union in a class scope. 1640 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1641 isa<RecordDecl>(Owner)) { 1642 Diag(DS.getStorageClassSpecLoc(), 1643 diag::err_anonymous_union_with_storage_spec); 1644 Invalid = true; 1645 1646 // Recover by removing the storage specifier. 1647 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1648 PrevSpec, DiagID); 1649 } 1650 1651 // C++ [class.union]p2: 1652 // The member-specification of an anonymous union shall only 1653 // define non-static data members. [Note: nested types and 1654 // functions cannot be declared within an anonymous union. ] 1655 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1656 MemEnd = Record->decls_end(); 1657 Mem != MemEnd; ++Mem) { 1658 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1659 // C++ [class.union]p3: 1660 // An anonymous union shall not have private or protected 1661 // members (clause 11). 1662 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1663 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1664 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1665 Invalid = true; 1666 } 1667 } else if ((*Mem)->isImplicit()) { 1668 // Any implicit members are fine. 1669 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1670 // This is a type that showed up in an 1671 // elaborated-type-specifier inside the anonymous struct or 1672 // union, but which actually declares a type outside of the 1673 // anonymous struct or union. It's okay. 1674 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1675 if (!MemRecord->isAnonymousStructOrUnion() && 1676 MemRecord->getDeclName()) { 1677 // This is a nested type declaration. 1678 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1679 << (int)Record->isUnion(); 1680 Invalid = true; 1681 } 1682 } else { 1683 // We have something that isn't a non-static data 1684 // member. Complain about it. 1685 unsigned DK = diag::err_anonymous_record_bad_member; 1686 if (isa<TypeDecl>(*Mem)) 1687 DK = diag::err_anonymous_record_with_type; 1688 else if (isa<FunctionDecl>(*Mem)) 1689 DK = diag::err_anonymous_record_with_function; 1690 else if (isa<VarDecl>(*Mem)) 1691 DK = diag::err_anonymous_record_with_static; 1692 Diag((*Mem)->getLocation(), DK) 1693 << (int)Record->isUnion(); 1694 Invalid = true; 1695 } 1696 } 1697 } 1698 1699 if (!Record->isUnion() && !Owner->isRecord()) { 1700 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1701 << (int)getLangOptions().CPlusPlus; 1702 Invalid = true; 1703 } 1704 1705 // Mock up a declarator. 1706 Declarator Dc(DS, Declarator::TypeNameContext); 1707 TypeSourceInfo *TInfo = 0; 1708 GetTypeForDeclarator(Dc, S, &TInfo); 1709 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1710 1711 // Create a declaration for this anonymous struct/union. 1712 NamedDecl *Anon = 0; 1713 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1714 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1715 /*IdentifierInfo=*/0, 1716 Context.getTypeDeclType(Record), 1717 TInfo, 1718 /*BitWidth=*/0, /*Mutable=*/false); 1719 Anon->setAccess(AS_public); 1720 if (getLangOptions().CPlusPlus) 1721 FieldCollector->Add(cast<FieldDecl>(Anon)); 1722 } else { 1723 VarDecl::StorageClass SC; 1724 switch (DS.getStorageClassSpec()) { 1725 default: assert(0 && "Unknown storage class!"); 1726 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1727 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1728 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1729 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1730 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1731 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1732 case DeclSpec::SCS_mutable: 1733 // mutable can only appear on non-static class members, so it's always 1734 // an error here 1735 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1736 Invalid = true; 1737 SC = VarDecl::None; 1738 break; 1739 } 1740 1741 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1742 /*IdentifierInfo=*/0, 1743 Context.getTypeDeclType(Record), 1744 TInfo, 1745 SC); 1746 } 1747 Anon->setImplicit(); 1748 1749 // Add the anonymous struct/union object to the current 1750 // context. We'll be referencing this object when we refer to one of 1751 // its members. 1752 Owner->addDecl(Anon); 1753 1754 // Inject the members of the anonymous struct/union into the owning 1755 // context and into the identifier resolver chain for name lookup 1756 // purposes. 1757 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1758 Invalid = true; 1759 1760 // Mark this as an anonymous struct/union type. Note that we do not 1761 // do this until after we have already checked and injected the 1762 // members of this anonymous struct/union type, because otherwise 1763 // the members could be injected twice: once by DeclContext when it 1764 // builds its lookup table, and once by 1765 // InjectAnonymousStructOrUnionMembers. 1766 Record->setAnonymousStructOrUnion(true); 1767 1768 if (Invalid) 1769 Anon->setInvalidDecl(); 1770 1771 return DeclPtrTy::make(Anon); 1772} 1773 1774 1775/// GetNameForDeclarator - Determine the full declaration name for the 1776/// given Declarator. 1777DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1778 return GetNameFromUnqualifiedId(D.getName()); 1779} 1780 1781/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1782DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1783 switch (Name.getKind()) { 1784 case UnqualifiedId::IK_Identifier: 1785 return DeclarationName(Name.Identifier); 1786 1787 case UnqualifiedId::IK_OperatorFunctionId: 1788 return Context.DeclarationNames.getCXXOperatorName( 1789 Name.OperatorFunctionId.Operator); 1790 1791 case UnqualifiedId::IK_LiteralOperatorId: 1792 return Context.DeclarationNames.getCXXLiteralOperatorName( 1793 Name.Identifier); 1794 1795 case UnqualifiedId::IK_ConversionFunctionId: { 1796 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1797 if (Ty.isNull()) 1798 return DeclarationName(); 1799 1800 return Context.DeclarationNames.getCXXConversionFunctionName( 1801 Context.getCanonicalType(Ty)); 1802 } 1803 1804 case UnqualifiedId::IK_ConstructorName: { 1805 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1806 if (Ty.isNull()) 1807 return DeclarationName(); 1808 1809 return Context.DeclarationNames.getCXXConstructorName( 1810 Context.getCanonicalType(Ty)); 1811 } 1812 1813 case UnqualifiedId::IK_DestructorName: { 1814 QualType Ty = GetTypeFromParser(Name.DestructorName); 1815 if (Ty.isNull()) 1816 return DeclarationName(); 1817 1818 return Context.DeclarationNames.getCXXDestructorName( 1819 Context.getCanonicalType(Ty)); 1820 } 1821 1822 case UnqualifiedId::IK_TemplateId: { 1823 TemplateName TName 1824 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1825 return Context.getNameForTemplate(TName); 1826 } 1827 } 1828 1829 assert(false && "Unknown name kind"); 1830 return DeclarationName(); 1831} 1832 1833/// isNearlyMatchingFunction - Determine whether the C++ functions 1834/// Declaration and Definition are "nearly" matching. This heuristic 1835/// is used to improve diagnostics in the case where an out-of-line 1836/// function definition doesn't match any declaration within 1837/// the class or namespace. 1838static bool isNearlyMatchingFunction(ASTContext &Context, 1839 FunctionDecl *Declaration, 1840 FunctionDecl *Definition) { 1841 if (Declaration->param_size() != Definition->param_size()) 1842 return false; 1843 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1844 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1845 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1846 1847 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1848 DefParamTy.getNonReferenceType())) 1849 return false; 1850 } 1851 1852 return true; 1853} 1854 1855Sema::DeclPtrTy 1856Sema::HandleDeclarator(Scope *S, Declarator &D, 1857 MultiTemplateParamsArg TemplateParamLists, 1858 bool IsFunctionDefinition) { 1859 DeclarationName Name = GetNameForDeclarator(D); 1860 1861 // All of these full declarators require an identifier. If it doesn't have 1862 // one, the ParsedFreeStandingDeclSpec action should be used. 1863 if (!Name) { 1864 if (!D.isInvalidType()) // Reject this if we think it is valid. 1865 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1866 diag::err_declarator_need_ident) 1867 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1868 return DeclPtrTy(); 1869 } 1870 1871 // The scope passed in may not be a decl scope. Zip up the scope tree until 1872 // we find one that is. 1873 while ((S->getFlags() & Scope::DeclScope) == 0 || 1874 (S->getFlags() & Scope::TemplateParamScope) != 0) 1875 S = S->getParent(); 1876 1877 // If this is an out-of-line definition of a member of a class template 1878 // or class template partial specialization, we may need to rebuild the 1879 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1880 // for more information. 1881 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1882 // handle expressions properly. 1883 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1884 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1885 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1886 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1887 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1888 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1889 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1890 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1891 // FIXME: Preserve type source info. 1892 QualType T = GetTypeFromParser(DS.getTypeRep()); 1893 1894 DeclContext *SavedContext = CurContext; 1895 CurContext = DC; 1896 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1897 CurContext = SavedContext; 1898 1899 if (T.isNull()) 1900 return DeclPtrTy(); 1901 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1902 } 1903 } 1904 1905 DeclContext *DC; 1906 NamedDecl *New; 1907 1908 TypeSourceInfo *TInfo = 0; 1909 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1910 1911 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1912 ForRedeclaration); 1913 1914 // See if this is a redefinition of a variable in the same scope. 1915 if (D.getCXXScopeSpec().isInvalid()) { 1916 DC = CurContext; 1917 D.setInvalidType(); 1918 } else if (!D.getCXXScopeSpec().isSet()) { 1919 bool IsLinkageLookup = false; 1920 1921 // If the declaration we're planning to build will be a function 1922 // or object with linkage, then look for another declaration with 1923 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1924 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1925 /* Do nothing*/; 1926 else if (R->isFunctionType()) { 1927 if (CurContext->isFunctionOrMethod() || 1928 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1929 IsLinkageLookup = true; 1930 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1931 IsLinkageLookup = true; 1932 else if (CurContext->getLookupContext()->isTranslationUnit() && 1933 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1934 IsLinkageLookup = true; 1935 1936 if (IsLinkageLookup) 1937 Previous.clear(LookupRedeclarationWithLinkage); 1938 1939 DC = CurContext; 1940 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1941 } else { // Something like "int foo::x;" 1942 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1943 1944 if (!DC) { 1945 // If we could not compute the declaration context, it's because the 1946 // declaration context is dependent but does not refer to a class, 1947 // class template, or class template partial specialization. Complain 1948 // and return early, to avoid the coming semantic disaster. 1949 Diag(D.getIdentifierLoc(), 1950 diag::err_template_qualified_declarator_no_match) 1951 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1952 << D.getCXXScopeSpec().getRange(); 1953 return DeclPtrTy(); 1954 } 1955 1956 if (!DC->isDependentContext() && 1957 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1958 return DeclPtrTy(); 1959 1960 LookupQualifiedName(Previous, DC); 1961 1962 // Don't consider using declarations as previous declarations for 1963 // out-of-line members. 1964 RemoveUsingDecls(Previous); 1965 1966 // C++ 7.3.1.2p2: 1967 // Members (including explicit specializations of templates) of a named 1968 // namespace can also be defined outside that namespace by explicit 1969 // qualification of the name being defined, provided that the entity being 1970 // defined was already declared in the namespace and the definition appears 1971 // after the point of declaration in a namespace that encloses the 1972 // declarations namespace. 1973 // 1974 // Note that we only check the context at this point. We don't yet 1975 // have enough information to make sure that PrevDecl is actually 1976 // the declaration we want to match. For example, given: 1977 // 1978 // class X { 1979 // void f(); 1980 // void f(float); 1981 // }; 1982 // 1983 // void X::f(int) { } // ill-formed 1984 // 1985 // In this case, PrevDecl will point to the overload set 1986 // containing the two f's declared in X, but neither of them 1987 // matches. 1988 1989 // First check whether we named the global scope. 1990 if (isa<TranslationUnitDecl>(DC)) { 1991 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1992 << Name << D.getCXXScopeSpec().getRange(); 1993 } else { 1994 DeclContext *Cur = CurContext; 1995 while (isa<LinkageSpecDecl>(Cur)) 1996 Cur = Cur->getParent(); 1997 if (!Cur->Encloses(DC)) { 1998 // The qualifying scope doesn't enclose the original declaration. 1999 // Emit diagnostic based on current scope. 2000 SourceLocation L = D.getIdentifierLoc(); 2001 SourceRange R = D.getCXXScopeSpec().getRange(); 2002 if (isa<FunctionDecl>(Cur)) 2003 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2004 else 2005 Diag(L, diag::err_invalid_declarator_scope) 2006 << Name << cast<NamedDecl>(DC) << R; 2007 D.setInvalidType(); 2008 } 2009 } 2010 } 2011 2012 if (Previous.isSingleResult() && 2013 Previous.getFoundDecl()->isTemplateParameter()) { 2014 // Maybe we will complain about the shadowed template parameter. 2015 if (!D.isInvalidType()) 2016 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2017 Previous.getFoundDecl())) 2018 D.setInvalidType(); 2019 2020 // Just pretend that we didn't see the previous declaration. 2021 Previous.clear(); 2022 } 2023 2024 // In C++, the previous declaration we find might be a tag type 2025 // (class or enum). In this case, the new declaration will hide the 2026 // tag type. Note that this does does not apply if we're declaring a 2027 // typedef (C++ [dcl.typedef]p4). 2028 if (Previous.isSingleTagDecl() && 2029 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2030 Previous.clear(); 2031 2032 bool Redeclaration = false; 2033 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2034 if (TemplateParamLists.size()) { 2035 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2036 return DeclPtrTy(); 2037 } 2038 2039 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2040 } else if (R->isFunctionType()) { 2041 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2042 move(TemplateParamLists), 2043 IsFunctionDefinition, Redeclaration); 2044 } else { 2045 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2046 move(TemplateParamLists), 2047 Redeclaration); 2048 } 2049 2050 if (New == 0) 2051 return DeclPtrTy(); 2052 2053 // If this has an identifier and is not an invalid redeclaration or 2054 // function template specialization, add it to the scope stack. 2055 if (Name && !(Redeclaration && New->isInvalidDecl())) 2056 PushOnScopeChains(New, S); 2057 2058 return DeclPtrTy::make(New); 2059} 2060 2061/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2062/// types into constant array types in certain situations which would otherwise 2063/// be errors (for GCC compatibility). 2064static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2065 ASTContext &Context, 2066 bool &SizeIsNegative) { 2067 // This method tries to turn a variable array into a constant 2068 // array even when the size isn't an ICE. This is necessary 2069 // for compatibility with code that depends on gcc's buggy 2070 // constant expression folding, like struct {char x[(int)(char*)2];} 2071 SizeIsNegative = false; 2072 2073 QualifierCollector Qs; 2074 const Type *Ty = Qs.strip(T); 2075 2076 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2077 QualType Pointee = PTy->getPointeeType(); 2078 QualType FixedType = 2079 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2080 if (FixedType.isNull()) return FixedType; 2081 FixedType = Context.getPointerType(FixedType); 2082 return Qs.apply(FixedType); 2083 } 2084 2085 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2086 if (!VLATy) 2087 return QualType(); 2088 // FIXME: We should probably handle this case 2089 if (VLATy->getElementType()->isVariablyModifiedType()) 2090 return QualType(); 2091 2092 Expr::EvalResult EvalResult; 2093 if (!VLATy->getSizeExpr() || 2094 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2095 !EvalResult.Val.isInt()) 2096 return QualType(); 2097 2098 llvm::APSInt &Res = EvalResult.Val.getInt(); 2099 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2100 // TODO: preserve the size expression in declarator info 2101 return Context.getConstantArrayType(VLATy->getElementType(), 2102 Res, ArrayType::Normal, 0); 2103 } 2104 2105 SizeIsNegative = true; 2106 return QualType(); 2107} 2108 2109/// \brief Register the given locally-scoped external C declaration so 2110/// that it can be found later for redeclarations 2111void 2112Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2113 const LookupResult &Previous, 2114 Scope *S) { 2115 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2116 "Decl is not a locally-scoped decl!"); 2117 // Note that we have a locally-scoped external with this name. 2118 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2119 2120 if (!Previous.isSingleResult()) 2121 return; 2122 2123 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2124 2125 // If there was a previous declaration of this variable, it may be 2126 // in our identifier chain. Update the identifier chain with the new 2127 // declaration. 2128 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2129 // The previous declaration was found on the identifer resolver 2130 // chain, so remove it from its scope. 2131 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2132 S = S->getParent(); 2133 2134 if (S) 2135 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2136 } 2137} 2138 2139/// \brief Diagnose function specifiers on a declaration of an identifier that 2140/// does not identify a function. 2141void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2142 // FIXME: We should probably indicate the identifier in question to avoid 2143 // confusion for constructs like "inline int a(), b;" 2144 if (D.getDeclSpec().isInlineSpecified()) 2145 Diag(D.getDeclSpec().getInlineSpecLoc(), 2146 diag::err_inline_non_function); 2147 2148 if (D.getDeclSpec().isVirtualSpecified()) 2149 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2150 diag::err_virtual_non_function); 2151 2152 if (D.getDeclSpec().isExplicitSpecified()) 2153 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2154 diag::err_explicit_non_function); 2155} 2156 2157NamedDecl* 2158Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2159 QualType R, TypeSourceInfo *TInfo, 2160 LookupResult &Previous, bool &Redeclaration) { 2161 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2162 if (D.getCXXScopeSpec().isSet()) { 2163 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2164 << D.getCXXScopeSpec().getRange(); 2165 D.setInvalidType(); 2166 // Pretend we didn't see the scope specifier. 2167 DC = 0; 2168 } 2169 2170 if (getLangOptions().CPlusPlus) { 2171 // Check that there are no default arguments (C++ only). 2172 CheckExtraCXXDefaultArguments(D); 2173 } 2174 2175 DiagnoseFunctionSpecifiers(D); 2176 2177 if (D.getDeclSpec().isThreadSpecified()) 2178 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2179 2180 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2181 if (!NewTD) return 0; 2182 2183 // Handle attributes prior to checking for duplicates in MergeVarDecl 2184 ProcessDeclAttributes(S, NewTD, D); 2185 2186 // Merge the decl with the existing one if appropriate. If the decl is 2187 // in an outer scope, it isn't the same thing. 2188 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2189 if (!Previous.empty()) { 2190 Redeclaration = true; 2191 MergeTypeDefDecl(NewTD, Previous); 2192 } 2193 2194 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2195 // then it shall have block scope. 2196 QualType T = NewTD->getUnderlyingType(); 2197 if (T->isVariablyModifiedType()) { 2198 CurFunctionNeedsScopeChecking = true; 2199 2200 if (S->getFnParent() == 0) { 2201 bool SizeIsNegative; 2202 QualType FixedTy = 2203 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2204 if (!FixedTy.isNull()) { 2205 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2206 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2207 } else { 2208 if (SizeIsNegative) 2209 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2210 else if (T->isVariableArrayType()) 2211 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2212 else 2213 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2214 NewTD->setInvalidDecl(); 2215 } 2216 } 2217 } 2218 2219 // If this is the C FILE type, notify the AST context. 2220 if (IdentifierInfo *II = NewTD->getIdentifier()) 2221 if (!NewTD->isInvalidDecl() && 2222 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2223 if (II->isStr("FILE")) 2224 Context.setFILEDecl(NewTD); 2225 else if (II->isStr("jmp_buf")) 2226 Context.setjmp_bufDecl(NewTD); 2227 else if (II->isStr("sigjmp_buf")) 2228 Context.setsigjmp_bufDecl(NewTD); 2229 } 2230 2231 return NewTD; 2232} 2233 2234/// \brief Determines whether the given declaration is an out-of-scope 2235/// previous declaration. 2236/// 2237/// This routine should be invoked when name lookup has found a 2238/// previous declaration (PrevDecl) that is not in the scope where a 2239/// new declaration by the same name is being introduced. If the new 2240/// declaration occurs in a local scope, previous declarations with 2241/// linkage may still be considered previous declarations (C99 2242/// 6.2.2p4-5, C++ [basic.link]p6). 2243/// 2244/// \param PrevDecl the previous declaration found by name 2245/// lookup 2246/// 2247/// \param DC the context in which the new declaration is being 2248/// declared. 2249/// 2250/// \returns true if PrevDecl is an out-of-scope previous declaration 2251/// for a new delcaration with the same name. 2252static bool 2253isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2254 ASTContext &Context) { 2255 if (!PrevDecl) 2256 return 0; 2257 2258 if (!PrevDecl->hasLinkage()) 2259 return false; 2260 2261 if (Context.getLangOptions().CPlusPlus) { 2262 // C++ [basic.link]p6: 2263 // If there is a visible declaration of an entity with linkage 2264 // having the same name and type, ignoring entities declared 2265 // outside the innermost enclosing namespace scope, the block 2266 // scope declaration declares that same entity and receives the 2267 // linkage of the previous declaration. 2268 DeclContext *OuterContext = DC->getLookupContext(); 2269 if (!OuterContext->isFunctionOrMethod()) 2270 // This rule only applies to block-scope declarations. 2271 return false; 2272 else { 2273 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2274 if (PrevOuterContext->isRecord()) 2275 // We found a member function: ignore it. 2276 return false; 2277 else { 2278 // Find the innermost enclosing namespace for the new and 2279 // previous declarations. 2280 while (!OuterContext->isFileContext()) 2281 OuterContext = OuterContext->getParent(); 2282 while (!PrevOuterContext->isFileContext()) 2283 PrevOuterContext = PrevOuterContext->getParent(); 2284 2285 // The previous declaration is in a different namespace, so it 2286 // isn't the same function. 2287 if (OuterContext->getPrimaryContext() != 2288 PrevOuterContext->getPrimaryContext()) 2289 return false; 2290 } 2291 } 2292 } 2293 2294 return true; 2295} 2296 2297NamedDecl* 2298Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2299 QualType R, TypeSourceInfo *TInfo, 2300 LookupResult &Previous, 2301 MultiTemplateParamsArg TemplateParamLists, 2302 bool &Redeclaration) { 2303 DeclarationName Name = GetNameForDeclarator(D); 2304 2305 // Check that there are no default arguments (C++ only). 2306 if (getLangOptions().CPlusPlus) 2307 CheckExtraCXXDefaultArguments(D); 2308 2309 VarDecl *NewVD; 2310 VarDecl::StorageClass SC; 2311 switch (D.getDeclSpec().getStorageClassSpec()) { 2312 default: assert(0 && "Unknown storage class!"); 2313 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2314 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2315 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2316 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2317 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2318 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2319 case DeclSpec::SCS_mutable: 2320 // mutable can only appear on non-static class members, so it's always 2321 // an error here 2322 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2323 D.setInvalidType(); 2324 SC = VarDecl::None; 2325 break; 2326 } 2327 2328 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2329 if (!II) { 2330 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2331 << Name.getAsString(); 2332 return 0; 2333 } 2334 2335 DiagnoseFunctionSpecifiers(D); 2336 2337 if (!DC->isRecord() && S->getFnParent() == 0) { 2338 // C99 6.9p2: The storage-class specifiers auto and register shall not 2339 // appear in the declaration specifiers in an external declaration. 2340 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2341 2342 // If this is a register variable with an asm label specified, then this 2343 // is a GNU extension. 2344 if (SC == VarDecl::Register && D.getAsmLabel()) 2345 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2346 else 2347 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2348 D.setInvalidType(); 2349 } 2350 } 2351 if (DC->isRecord() && !CurContext->isRecord()) { 2352 // This is an out-of-line definition of a static data member. 2353 if (SC == VarDecl::Static) { 2354 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2355 diag::err_static_out_of_line) 2356 << CodeModificationHint::CreateRemoval( 2357 D.getDeclSpec().getStorageClassSpecLoc()); 2358 } else if (SC == VarDecl::None) 2359 SC = VarDecl::Static; 2360 } 2361 if (SC == VarDecl::Static) { 2362 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2363 if (RD->isLocalClass()) 2364 Diag(D.getIdentifierLoc(), 2365 diag::err_static_data_member_not_allowed_in_local_class) 2366 << Name << RD->getDeclName(); 2367 } 2368 } 2369 2370 // Match up the template parameter lists with the scope specifier, then 2371 // determine whether we have a template or a template specialization. 2372 bool isExplicitSpecialization = false; 2373 if (TemplateParameterList *TemplateParams 2374 = MatchTemplateParametersToScopeSpecifier( 2375 D.getDeclSpec().getSourceRange().getBegin(), 2376 D.getCXXScopeSpec(), 2377 (TemplateParameterList**)TemplateParamLists.get(), 2378 TemplateParamLists.size(), 2379 isExplicitSpecialization)) { 2380 if (TemplateParams->size() > 0) { 2381 // There is no such thing as a variable template. 2382 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2383 << II 2384 << SourceRange(TemplateParams->getTemplateLoc(), 2385 TemplateParams->getRAngleLoc()); 2386 return 0; 2387 } else { 2388 // There is an extraneous 'template<>' for this variable. Complain 2389 // about it, but allow the declaration of the variable. 2390 Diag(TemplateParams->getTemplateLoc(), 2391 diag::err_template_variable_noparams) 2392 << II 2393 << SourceRange(TemplateParams->getTemplateLoc(), 2394 TemplateParams->getRAngleLoc()); 2395 2396 isExplicitSpecialization = true; 2397 } 2398 } 2399 2400 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2401 II, R, TInfo, SC); 2402 2403 if (D.isInvalidType()) 2404 NewVD->setInvalidDecl(); 2405 2406 if (D.getDeclSpec().isThreadSpecified()) { 2407 if (NewVD->hasLocalStorage()) 2408 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2409 else if (!Context.Target.isTLSSupported()) 2410 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2411 else 2412 NewVD->setThreadSpecified(true); 2413 } 2414 2415 // Set the lexical context. If the declarator has a C++ scope specifier, the 2416 // lexical context will be different from the semantic context. 2417 NewVD->setLexicalDeclContext(CurContext); 2418 2419 // Handle attributes prior to checking for duplicates in MergeVarDecl 2420 ProcessDeclAttributes(S, NewVD, D); 2421 2422 // Handle GNU asm-label extension (encoded as an attribute). 2423 if (Expr *E = (Expr*) D.getAsmLabel()) { 2424 // The parser guarantees this is a string. 2425 StringLiteral *SE = cast<StringLiteral>(E); 2426 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2427 } 2428 2429 // Don't consider existing declarations that are in a different 2430 // scope and are out-of-semantic-context declarations (if the new 2431 // declaration has linkage). 2432 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2433 2434 // Merge the decl with the existing one if appropriate. 2435 if (!Previous.empty()) { 2436 if (Previous.isSingleResult() && 2437 isa<FieldDecl>(Previous.getFoundDecl()) && 2438 D.getCXXScopeSpec().isSet()) { 2439 // The user tried to define a non-static data member 2440 // out-of-line (C++ [dcl.meaning]p1). 2441 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2442 << D.getCXXScopeSpec().getRange(); 2443 Previous.clear(); 2444 NewVD->setInvalidDecl(); 2445 } 2446 } else if (D.getCXXScopeSpec().isSet()) { 2447 // No previous declaration in the qualifying scope. 2448 Diag(D.getIdentifierLoc(), diag::err_no_member) 2449 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2450 << D.getCXXScopeSpec().getRange(); 2451 NewVD->setInvalidDecl(); 2452 } 2453 2454 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2455 2456 // This is an explicit specialization of a static data member. Check it. 2457 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2458 CheckMemberSpecialization(NewVD, Previous)) 2459 NewVD->setInvalidDecl(); 2460 2461 // attributes declared post-definition are currently ignored 2462 if (Previous.isSingleResult()) { 2463 const VarDecl *Def = 0; 2464 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2465 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2466 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2467 Diag(Def->getLocation(), diag::note_previous_definition); 2468 } 2469 } 2470 2471 // If this is a locally-scoped extern C variable, update the map of 2472 // such variables. 2473 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2474 !NewVD->isInvalidDecl()) 2475 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2476 2477 return NewVD; 2478} 2479 2480/// \brief Perform semantic checking on a newly-created variable 2481/// declaration. 2482/// 2483/// This routine performs all of the type-checking required for a 2484/// variable declaration once it has been built. It is used both to 2485/// check variables after they have been parsed and their declarators 2486/// have been translated into a declaration, and to check variables 2487/// that have been instantiated from a template. 2488/// 2489/// Sets NewVD->isInvalidDecl() if an error was encountered. 2490void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2491 LookupResult &Previous, 2492 bool &Redeclaration) { 2493 // If the decl is already known invalid, don't check it. 2494 if (NewVD->isInvalidDecl()) 2495 return; 2496 2497 QualType T = NewVD->getType(); 2498 2499 if (T->isObjCInterfaceType()) { 2500 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2501 return NewVD->setInvalidDecl(); 2502 } 2503 2504 // Emit an error if an address space was applied to decl with local storage. 2505 // This includes arrays of objects with address space qualifiers, but not 2506 // automatic variables that point to other address spaces. 2507 // ISO/IEC TR 18037 S5.1.2 2508 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2509 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2510 return NewVD->setInvalidDecl(); 2511 } 2512 2513 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2514 && !NewVD->hasAttr<BlocksAttr>()) 2515 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2516 2517 bool isVM = T->isVariablyModifiedType(); 2518 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2519 NewVD->hasAttr<BlocksAttr>()) 2520 CurFunctionNeedsScopeChecking = true; 2521 2522 if ((isVM && NewVD->hasLinkage()) || 2523 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2524 bool SizeIsNegative; 2525 QualType FixedTy = 2526 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2527 2528 if (FixedTy.isNull() && T->isVariableArrayType()) { 2529 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2530 // FIXME: This won't give the correct result for 2531 // int a[10][n]; 2532 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2533 2534 if (NewVD->isFileVarDecl()) 2535 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2536 << SizeRange; 2537 else if (NewVD->getStorageClass() == VarDecl::Static) 2538 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2539 << SizeRange; 2540 else 2541 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2542 << SizeRange; 2543 return NewVD->setInvalidDecl(); 2544 } 2545 2546 if (FixedTy.isNull()) { 2547 if (NewVD->isFileVarDecl()) 2548 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2549 else 2550 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2551 return NewVD->setInvalidDecl(); 2552 } 2553 2554 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2555 NewVD->setType(FixedTy); 2556 } 2557 2558 if (Previous.empty() && NewVD->isExternC()) { 2559 // Since we did not find anything by this name and we're declaring 2560 // an extern "C" variable, look for a non-visible extern "C" 2561 // declaration with the same name. 2562 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2563 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2564 if (Pos != LocallyScopedExternalDecls.end()) 2565 Previous.addDecl(Pos->second); 2566 } 2567 2568 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2569 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2570 << T; 2571 return NewVD->setInvalidDecl(); 2572 } 2573 2574 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2575 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2576 return NewVD->setInvalidDecl(); 2577 } 2578 2579 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2580 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2581 return NewVD->setInvalidDecl(); 2582 } 2583 2584 if (!Previous.empty()) { 2585 Redeclaration = true; 2586 MergeVarDecl(NewVD, Previous); 2587 } 2588} 2589 2590/// \brief Data used with FindOverriddenMethod 2591struct FindOverriddenMethodData { 2592 Sema *S; 2593 CXXMethodDecl *Method; 2594}; 2595 2596/// \brief Member lookup function that determines whether a given C++ 2597/// method overrides a method in a base class, to be used with 2598/// CXXRecordDecl::lookupInBases(). 2599static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2600 CXXBasePath &Path, 2601 void *UserData) { 2602 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2603 2604 FindOverriddenMethodData *Data 2605 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2606 2607 DeclarationName Name = Data->Method->getDeclName(); 2608 2609 // FIXME: Do we care about other names here too? 2610 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2611 // We really want to find the base class constructor here. 2612 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2613 CanQualType CT = Data->S->Context.getCanonicalType(T); 2614 2615 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2616 } 2617 2618 for (Path.Decls = BaseRecord->lookup(Name); 2619 Path.Decls.first != Path.Decls.second; 2620 ++Path.Decls.first) { 2621 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2622 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2623 return true; 2624 } 2625 } 2626 2627 return false; 2628} 2629 2630/// AddOverriddenMethods - See if a method overrides any in the base classes, 2631/// and if so, check that it's a valid override and remember it. 2632void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2633 // Look for virtual methods in base classes that this method might override. 2634 CXXBasePaths Paths; 2635 FindOverriddenMethodData Data; 2636 Data.Method = MD; 2637 Data.S = this; 2638 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2639 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2640 E = Paths.found_decls_end(); I != E; ++I) { 2641 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2642 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2643 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2644 !CheckOverridingFunctionAttributes(MD, OldMD)) 2645 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2646 } 2647 } 2648 } 2649} 2650 2651NamedDecl* 2652Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2653 QualType R, TypeSourceInfo *TInfo, 2654 LookupResult &Previous, 2655 MultiTemplateParamsArg TemplateParamLists, 2656 bool IsFunctionDefinition, bool &Redeclaration) { 2657 assert(R.getTypePtr()->isFunctionType()); 2658 2659 DeclarationName Name = GetNameForDeclarator(D); 2660 FunctionDecl::StorageClass SC = FunctionDecl::None; 2661 switch (D.getDeclSpec().getStorageClassSpec()) { 2662 default: assert(0 && "Unknown storage class!"); 2663 case DeclSpec::SCS_auto: 2664 case DeclSpec::SCS_register: 2665 case DeclSpec::SCS_mutable: 2666 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2667 diag::err_typecheck_sclass_func); 2668 D.setInvalidType(); 2669 break; 2670 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2671 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2672 case DeclSpec::SCS_static: { 2673 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2674 // C99 6.7.1p5: 2675 // The declaration of an identifier for a function that has 2676 // block scope shall have no explicit storage-class specifier 2677 // other than extern 2678 // See also (C++ [dcl.stc]p4). 2679 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2680 diag::err_static_block_func); 2681 SC = FunctionDecl::None; 2682 } else 2683 SC = FunctionDecl::Static; 2684 break; 2685 } 2686 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2687 } 2688 2689 if (D.getDeclSpec().isThreadSpecified()) 2690 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2691 2692 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2693 bool isInline = D.getDeclSpec().isInlineSpecified(); 2694 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2695 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2696 2697 // Check that the return type is not an abstract class type. 2698 // For record types, this is done by the AbstractClassUsageDiagnoser once 2699 // the class has been completely parsed. 2700 if (!DC->isRecord() && 2701 RequireNonAbstractType(D.getIdentifierLoc(), 2702 R->getAs<FunctionType>()->getResultType(), 2703 diag::err_abstract_type_in_decl, 2704 AbstractReturnType)) 2705 D.setInvalidType(); 2706 2707 // Do not allow returning a objc interface by-value. 2708 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2709 Diag(D.getIdentifierLoc(), 2710 diag::err_object_cannot_be_passed_returned_by_value) << 0 2711 << R->getAs<FunctionType>()->getResultType(); 2712 D.setInvalidType(); 2713 } 2714 2715 bool isVirtualOkay = false; 2716 FunctionDecl *NewFD; 2717 2718 if (isFriend) { 2719 // C++ [class.friend]p5 2720 // A function can be defined in a friend declaration of a 2721 // class . . . . Such a function is implicitly inline. 2722 isInline |= IsFunctionDefinition; 2723 } 2724 2725 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2726 // This is a C++ constructor declaration. 2727 assert(DC->isRecord() && 2728 "Constructors can only be declared in a member context"); 2729 2730 R = CheckConstructorDeclarator(D, R, SC); 2731 2732 // Create the new declaration 2733 NewFD = CXXConstructorDecl::Create(Context, 2734 cast<CXXRecordDecl>(DC), 2735 D.getIdentifierLoc(), Name, R, TInfo, 2736 isExplicit, isInline, 2737 /*isImplicitlyDeclared=*/false); 2738 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2739 // This is a C++ destructor declaration. 2740 if (DC->isRecord()) { 2741 R = CheckDestructorDeclarator(D, SC); 2742 2743 NewFD = CXXDestructorDecl::Create(Context, 2744 cast<CXXRecordDecl>(DC), 2745 D.getIdentifierLoc(), Name, R, 2746 isInline, 2747 /*isImplicitlyDeclared=*/false); 2748 2749 isVirtualOkay = true; 2750 } else { 2751 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2752 2753 // Create a FunctionDecl to satisfy the function definition parsing 2754 // code path. 2755 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2756 Name, R, TInfo, SC, isInline, 2757 /*hasPrototype=*/true); 2758 D.setInvalidType(); 2759 } 2760 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2761 if (!DC->isRecord()) { 2762 Diag(D.getIdentifierLoc(), 2763 diag::err_conv_function_not_member); 2764 return 0; 2765 } 2766 2767 CheckConversionDeclarator(D, R, SC); 2768 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2769 D.getIdentifierLoc(), Name, R, TInfo, 2770 isInline, isExplicit); 2771 2772 isVirtualOkay = true; 2773 } else if (DC->isRecord()) { 2774 // If the of the function is the same as the name of the record, then this 2775 // must be an invalid constructor that has a return type. 2776 // (The parser checks for a return type and makes the declarator a 2777 // constructor if it has no return type). 2778 // must have an invalid constructor that has a return type 2779 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2780 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2781 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2782 << SourceRange(D.getIdentifierLoc()); 2783 return 0; 2784 } 2785 2786 bool isStatic = SC == FunctionDecl::Static; 2787 2788 // [class.free]p1: 2789 // Any allocation function for a class T is a static member 2790 // (even if not explicitly declared static). 2791 if (Name.getCXXOverloadedOperator() == OO_New || 2792 Name.getCXXOverloadedOperator() == OO_Array_New) 2793 isStatic = true; 2794 2795 // [class.free]p6 Any deallocation function for a class X is a static member 2796 // (even if not explicitly declared static). 2797 if (Name.getCXXOverloadedOperator() == OO_Delete || 2798 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2799 isStatic = true; 2800 2801 // This is a C++ method declaration. 2802 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2803 D.getIdentifierLoc(), Name, R, TInfo, 2804 isStatic, isInline); 2805 2806 isVirtualOkay = !isStatic; 2807 } else { 2808 // Determine whether the function was written with a 2809 // prototype. This true when: 2810 // - we're in C++ (where every function has a prototype), 2811 // - there is a prototype in the declarator, or 2812 // - the type R of the function is some kind of typedef or other reference 2813 // to a type name (which eventually refers to a function type). 2814 bool HasPrototype = 2815 getLangOptions().CPlusPlus || 2816 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2817 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2818 2819 NewFD = FunctionDecl::Create(Context, DC, 2820 D.getIdentifierLoc(), 2821 Name, R, TInfo, SC, isInline, HasPrototype); 2822 } 2823 2824 if (D.isInvalidType()) 2825 NewFD->setInvalidDecl(); 2826 2827 // Set the lexical context. If the declarator has a C++ 2828 // scope specifier, or is the object of a friend declaration, the 2829 // lexical context will be different from the semantic context. 2830 NewFD->setLexicalDeclContext(CurContext); 2831 2832 // Match up the template parameter lists with the scope specifier, then 2833 // determine whether we have a template or a template specialization. 2834 FunctionTemplateDecl *FunctionTemplate = 0; 2835 bool isExplicitSpecialization = false; 2836 bool isFunctionTemplateSpecialization = false; 2837 if (TemplateParameterList *TemplateParams 2838 = MatchTemplateParametersToScopeSpecifier( 2839 D.getDeclSpec().getSourceRange().getBegin(), 2840 D.getCXXScopeSpec(), 2841 (TemplateParameterList**)TemplateParamLists.get(), 2842 TemplateParamLists.size(), 2843 isExplicitSpecialization)) { 2844 if (TemplateParams->size() > 0) { 2845 // This is a function template 2846 2847 // Check that we can declare a template here. 2848 if (CheckTemplateDeclScope(S, TemplateParams)) 2849 return 0; 2850 2851 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2852 NewFD->getLocation(), 2853 Name, TemplateParams, 2854 NewFD); 2855 FunctionTemplate->setLexicalDeclContext(CurContext); 2856 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2857 } else { 2858 // This is a function template specialization. 2859 isFunctionTemplateSpecialization = true; 2860 } 2861 2862 // FIXME: Free this memory properly. 2863 TemplateParamLists.release(); 2864 } 2865 2866 // C++ [dcl.fct.spec]p5: 2867 // The virtual specifier shall only be used in declarations of 2868 // nonstatic class member functions that appear within a 2869 // member-specification of a class declaration; see 10.3. 2870 // 2871 if (isVirtual && !NewFD->isInvalidDecl()) { 2872 if (!isVirtualOkay) { 2873 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2874 diag::err_virtual_non_function); 2875 } else if (!CurContext->isRecord()) { 2876 // 'virtual' was specified outside of the class. 2877 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2878 << CodeModificationHint::CreateRemoval( 2879 D.getDeclSpec().getVirtualSpecLoc()); 2880 } else { 2881 // Okay: Add virtual to the method. 2882 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2883 CurClass->setMethodAsVirtual(NewFD); 2884 } 2885 } 2886 2887 // Filter out previous declarations that don't match the scope. 2888 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2889 2890 if (isFriend) { 2891 // DC is the namespace in which the function is being declared. 2892 assert((DC->isFileContext() || !Previous.empty()) && 2893 "previously-undeclared friend function being created " 2894 "in a non-namespace context"); 2895 2896 if (FunctionTemplate) { 2897 FunctionTemplate->setObjectOfFriendDecl( 2898 /* PreviouslyDeclared= */ !Previous.empty()); 2899 FunctionTemplate->setAccess(AS_public); 2900 } 2901 else 2902 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2903 2904 NewFD->setAccess(AS_public); 2905 } 2906 2907 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2908 !CurContext->isRecord()) { 2909 // C++ [class.static]p1: 2910 // A data or function member of a class may be declared static 2911 // in a class definition, in which case it is a static member of 2912 // the class. 2913 2914 // Complain about the 'static' specifier if it's on an out-of-line 2915 // member function definition. 2916 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2917 diag::err_static_out_of_line) 2918 << CodeModificationHint::CreateRemoval( 2919 D.getDeclSpec().getStorageClassSpecLoc()); 2920 } 2921 2922 // Handle GNU asm-label extension (encoded as an attribute). 2923 if (Expr *E = (Expr*) D.getAsmLabel()) { 2924 // The parser guarantees this is a string. 2925 StringLiteral *SE = cast<StringLiteral>(E); 2926 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2927 } 2928 2929 // Copy the parameter declarations from the declarator D to the function 2930 // declaration NewFD, if they are available. First scavenge them into Params. 2931 llvm::SmallVector<ParmVarDecl*, 16> Params; 2932 if (D.getNumTypeObjects() > 0) { 2933 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2934 2935 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2936 // function that takes no arguments, not a function that takes a 2937 // single void argument. 2938 // We let through "const void" here because Sema::GetTypeForDeclarator 2939 // already checks for that case. 2940 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2941 FTI.ArgInfo[0].Param && 2942 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2943 // Empty arg list, don't push any params. 2944 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2945 2946 // In C++, the empty parameter-type-list must be spelled "void"; a 2947 // typedef of void is not permitted. 2948 if (getLangOptions().CPlusPlus && 2949 Param->getType().getUnqualifiedType() != Context.VoidTy) 2950 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2951 // FIXME: Leaks decl? 2952 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2953 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2954 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2955 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2956 Param->setDeclContext(NewFD); 2957 Params.push_back(Param); 2958 } 2959 } 2960 2961 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2962 // When we're declaring a function with a typedef, typeof, etc as in the 2963 // following example, we'll need to synthesize (unnamed) 2964 // parameters for use in the declaration. 2965 // 2966 // @code 2967 // typedef void fn(int); 2968 // fn f; 2969 // @endcode 2970 2971 // Synthesize a parameter for each argument type. 2972 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2973 AE = FT->arg_type_end(); AI != AE; ++AI) { 2974 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2975 SourceLocation(), 0, 2976 *AI, /*TInfo=*/0, 2977 VarDecl::None, 0); 2978 Param->setImplicit(); 2979 Params.push_back(Param); 2980 } 2981 } else { 2982 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2983 "Should not need args for typedef of non-prototype fn"); 2984 } 2985 // Finally, we know we have the right number of parameters, install them. 2986 NewFD->setParams(Context, Params.data(), Params.size()); 2987 2988 // If the declarator is a template-id, translate the parser's template 2989 // argument list into our AST format. 2990 bool HasExplicitTemplateArgs = false; 2991 TemplateArgumentListInfo TemplateArgs; 2992 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2993 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2994 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 2995 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 2996 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2997 TemplateId->getTemplateArgs(), 2998 TemplateId->NumArgs); 2999 translateTemplateArguments(TemplateArgsPtr, 3000 TemplateArgs); 3001 TemplateArgsPtr.release(); 3002 3003 HasExplicitTemplateArgs = true; 3004 3005 if (FunctionTemplate) { 3006 // FIXME: Diagnose function template with explicit template 3007 // arguments. 3008 HasExplicitTemplateArgs = false; 3009 } else if (!isFunctionTemplateSpecialization && 3010 !D.getDeclSpec().isFriendSpecified()) { 3011 // We have encountered something that the user meant to be a 3012 // specialization (because it has explicitly-specified template 3013 // arguments) but that was not introduced with a "template<>" (or had 3014 // too few of them). 3015 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3016 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3017 << CodeModificationHint::CreateInsertion( 3018 D.getDeclSpec().getSourceRange().getBegin(), 3019 "template<> "); 3020 isFunctionTemplateSpecialization = true; 3021 } 3022 } 3023 3024 if (isFunctionTemplateSpecialization) { 3025 if (CheckFunctionTemplateSpecialization(NewFD, 3026 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3027 Previous)) 3028 NewFD->setInvalidDecl(); 3029 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3030 CheckMemberSpecialization(NewFD, Previous)) 3031 NewFD->setInvalidDecl(); 3032 3033 // Perform semantic checking on the function declaration. 3034 bool OverloadableAttrRequired = false; // FIXME: HACK! 3035 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3036 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3037 3038 assert((NewFD->isInvalidDecl() || !Redeclaration || 3039 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3040 "previous declaration set still overloaded"); 3041 3042 // If we have a function template, check the template parameter 3043 // list. This will check and merge default template arguments. 3044 if (FunctionTemplate) { 3045 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3046 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3047 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3048 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3049 : TPC_FunctionTemplate); 3050 } 3051 3052 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3053 // An out-of-line member function declaration must also be a 3054 // definition (C++ [dcl.meaning]p1). 3055 // Note that this is not the case for explicit specializations of 3056 // function templates or member functions of class templates, per 3057 // C++ [temp.expl.spec]p2. 3058 if (!IsFunctionDefinition && !isFriend && 3059 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3060 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3061 << D.getCXXScopeSpec().getRange(); 3062 NewFD->setInvalidDecl(); 3063 } else if (!Redeclaration) { 3064 // The user tried to provide an out-of-line definition for a 3065 // function that is a member of a class or namespace, but there 3066 // was no such member function declared (C++ [class.mfct]p2, 3067 // C++ [namespace.memdef]p2). For example: 3068 // 3069 // class X { 3070 // void f() const; 3071 // }; 3072 // 3073 // void X::f() { } // ill-formed 3074 // 3075 // Complain about this problem, and attempt to suggest close 3076 // matches (e.g., those that differ only in cv-qualifiers and 3077 // whether the parameter types are references). 3078 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3079 << Name << DC << D.getCXXScopeSpec().getRange(); 3080 NewFD->setInvalidDecl(); 3081 3082 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3083 ForRedeclaration); 3084 LookupQualifiedName(Prev, DC); 3085 assert(!Prev.isAmbiguous() && 3086 "Cannot have an ambiguity in previous-declaration lookup"); 3087 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3088 Func != FuncEnd; ++Func) { 3089 if (isa<FunctionDecl>(*Func) && 3090 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3091 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3092 } 3093 } 3094 } 3095 3096 // Handle attributes. We need to have merged decls when handling attributes 3097 // (for example to check for conflicts, etc). 3098 // FIXME: This needs to happen before we merge declarations. Then, 3099 // let attribute merging cope with attribute conflicts. 3100 ProcessDeclAttributes(S, NewFD, D); 3101 3102 // attributes declared post-definition are currently ignored 3103 if (Redeclaration && Previous.isSingleResult()) { 3104 const FunctionDecl *Def; 3105 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3106 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3107 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3108 Diag(Def->getLocation(), diag::note_previous_definition); 3109 } 3110 } 3111 3112 AddKnownFunctionAttributes(NewFD); 3113 3114 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3115 // If a function name is overloadable in C, then every function 3116 // with that name must be marked "overloadable". 3117 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3118 << Redeclaration << NewFD; 3119 if (!Previous.empty()) 3120 Diag(Previous.getRepresentativeDecl()->getLocation(), 3121 diag::note_attribute_overloadable_prev_overload); 3122 NewFD->addAttr(::new (Context) OverloadableAttr()); 3123 } 3124 3125 // If this is a locally-scoped extern C function, update the 3126 // map of such names. 3127 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3128 && !NewFD->isInvalidDecl()) 3129 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3130 3131 // Set this FunctionDecl's range up to the right paren. 3132 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3133 3134 if (FunctionTemplate && NewFD->isInvalidDecl()) 3135 FunctionTemplate->setInvalidDecl(); 3136 3137 if (FunctionTemplate) 3138 return FunctionTemplate; 3139 3140 return NewFD; 3141} 3142 3143/// \brief Perform semantic checking of a new function declaration. 3144/// 3145/// Performs semantic analysis of the new function declaration 3146/// NewFD. This routine performs all semantic checking that does not 3147/// require the actual declarator involved in the declaration, and is 3148/// used both for the declaration of functions as they are parsed 3149/// (called via ActOnDeclarator) and for the declaration of functions 3150/// that have been instantiated via C++ template instantiation (called 3151/// via InstantiateDecl). 3152/// 3153/// \param IsExplicitSpecialiation whether this new function declaration is 3154/// an explicit specialization of the previous declaration. 3155/// 3156/// This sets NewFD->isInvalidDecl() to true if there was an error. 3157void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3158 LookupResult &Previous, 3159 bool IsExplicitSpecialization, 3160 bool &Redeclaration, 3161 bool &OverloadableAttrRequired) { 3162 // If NewFD is already known erroneous, don't do any of this checking. 3163 if (NewFD->isInvalidDecl()) 3164 return; 3165 3166 if (NewFD->getResultType()->isVariablyModifiedType()) { 3167 // Functions returning a variably modified type violate C99 6.7.5.2p2 3168 // because all functions have linkage. 3169 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3170 return NewFD->setInvalidDecl(); 3171 } 3172 3173 if (NewFD->isMain()) 3174 CheckMain(NewFD); 3175 3176 // Check for a previous declaration of this name. 3177 if (Previous.empty() && NewFD->isExternC()) { 3178 // Since we did not find anything by this name and we're declaring 3179 // an extern "C" function, look for a non-visible extern "C" 3180 // declaration with the same name. 3181 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3182 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3183 if (Pos != LocallyScopedExternalDecls.end()) 3184 Previous.addDecl(Pos->second); 3185 } 3186 3187 // Merge or overload the declaration with an existing declaration of 3188 // the same name, if appropriate. 3189 if (!Previous.empty()) { 3190 // Determine whether NewFD is an overload of PrevDecl or 3191 // a declaration that requires merging. If it's an overload, 3192 // there's no more work to do here; we'll just add the new 3193 // function to the scope. 3194 3195 NamedDecl *OldDecl = 0; 3196 if (!AllowOverloadingOfFunction(Previous, Context)) { 3197 Redeclaration = true; 3198 OldDecl = Previous.getFoundDecl(); 3199 } else { 3200 if (!getLangOptions().CPlusPlus) { 3201 OverloadableAttrRequired = true; 3202 3203 // Functions marked "overloadable" must have a prototype (that 3204 // we can't get through declaration merging). 3205 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3206 Diag(NewFD->getLocation(), 3207 diag::err_attribute_overloadable_no_prototype) 3208 << NewFD; 3209 Redeclaration = true; 3210 3211 // Turn this into a variadic function with no parameters. 3212 QualType R = Context.getFunctionType( 3213 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3214 0, 0, true, 0); 3215 NewFD->setType(R); 3216 return NewFD->setInvalidDecl(); 3217 } 3218 } 3219 3220 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3221 case Ovl_Match: 3222 Redeclaration = true; 3223 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3224 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3225 Redeclaration = false; 3226 } 3227 break; 3228 3229 case Ovl_NonFunction: 3230 Redeclaration = true; 3231 break; 3232 3233 case Ovl_Overload: 3234 Redeclaration = false; 3235 break; 3236 } 3237 } 3238 3239 if (Redeclaration) { 3240 // NewFD and OldDecl represent declarations that need to be 3241 // merged. 3242 if (MergeFunctionDecl(NewFD, OldDecl)) 3243 return NewFD->setInvalidDecl(); 3244 3245 Previous.clear(); 3246 Previous.addDecl(OldDecl); 3247 3248 if (FunctionTemplateDecl *OldTemplateDecl 3249 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3250 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3251 FunctionTemplateDecl *NewTemplateDecl 3252 = NewFD->getDescribedFunctionTemplate(); 3253 assert(NewTemplateDecl && "Template/non-template mismatch"); 3254 if (CXXMethodDecl *Method 3255 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3256 Method->setAccess(OldTemplateDecl->getAccess()); 3257 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3258 } 3259 3260 // If this is an explicit specialization of a member that is a function 3261 // template, mark it as a member specialization. 3262 if (IsExplicitSpecialization && 3263 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3264 NewTemplateDecl->setMemberSpecialization(); 3265 assert(OldTemplateDecl->isMemberSpecialization()); 3266 } 3267 } else { 3268 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3269 NewFD->setAccess(OldDecl->getAccess()); 3270 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3271 } 3272 } 3273 } 3274 3275 // Semantic checking for this function declaration (in isolation). 3276 if (getLangOptions().CPlusPlus) { 3277 // C++-specific checks. 3278 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3279 CheckConstructor(Constructor); 3280 } else if (CXXDestructorDecl *Destructor = 3281 dyn_cast<CXXDestructorDecl>(NewFD)) { 3282 CXXRecordDecl *Record = Destructor->getParent(); 3283 QualType ClassType = Context.getTypeDeclType(Record); 3284 3285 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3286 // type is dependent? Both gcc and edg can handle that. 3287 if (!ClassType->isDependentType()) { 3288 DeclarationName Name 3289 = Context.DeclarationNames.getCXXDestructorName( 3290 Context.getCanonicalType(ClassType)); 3291 if (NewFD->getDeclName() != Name) { 3292 Diag(NewFD->getLocation(), diag::err_destructor_name); 3293 return NewFD->setInvalidDecl(); 3294 } 3295 } 3296 3297 Record->setUserDeclaredDestructor(true); 3298 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3299 // user-defined destructor. 3300 Record->setPOD(false); 3301 3302 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3303 // declared destructor. 3304 // FIXME: C++0x: don't do this for "= default" destructors 3305 Record->setHasTrivialDestructor(false); 3306 } else if (CXXConversionDecl *Conversion 3307 = dyn_cast<CXXConversionDecl>(NewFD)) { 3308 ActOnConversionDeclarator(Conversion); 3309 } 3310 3311 // Find any virtual functions that this function overrides. 3312 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3313 if (!Method->isFunctionTemplateSpecialization() && 3314 !Method->getDescribedFunctionTemplate()) 3315 AddOverriddenMethods(Method->getParent(), Method); 3316 } 3317 3318 // Additional checks for the destructor; make sure we do this after we 3319 // figure out whether the destructor is virtual. 3320 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3321 if (!Destructor->getParent()->isDependentType()) 3322 CheckDestructor(Destructor); 3323 3324 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3325 if (NewFD->isOverloadedOperator() && 3326 CheckOverloadedOperatorDeclaration(NewFD)) 3327 return NewFD->setInvalidDecl(); 3328 3329 // In C++, check default arguments now that we have merged decls. Unless 3330 // the lexical context is the class, because in this case this is done 3331 // during delayed parsing anyway. 3332 if (!CurContext->isRecord()) 3333 CheckCXXDefaultArguments(NewFD); 3334 } 3335} 3336 3337void Sema::CheckMain(FunctionDecl* FD) { 3338 // C++ [basic.start.main]p3: A program that declares main to be inline 3339 // or static is ill-formed. 3340 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3341 // shall not appear in a declaration of main. 3342 // static main is not an error under C99, but we should warn about it. 3343 bool isInline = FD->isInlineSpecified(); 3344 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3345 if (isInline || isStatic) { 3346 unsigned diagID = diag::warn_unusual_main_decl; 3347 if (isInline || getLangOptions().CPlusPlus) 3348 diagID = diag::err_unusual_main_decl; 3349 3350 int which = isStatic + (isInline << 1) - 1; 3351 Diag(FD->getLocation(), diagID) << which; 3352 } 3353 3354 QualType T = FD->getType(); 3355 assert(T->isFunctionType() && "function decl is not of function type"); 3356 const FunctionType* FT = T->getAs<FunctionType>(); 3357 3358 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3359 // TODO: add a replacement fixit to turn the return type into 'int'. 3360 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3361 FD->setInvalidDecl(true); 3362 } 3363 3364 // Treat protoless main() as nullary. 3365 if (isa<FunctionNoProtoType>(FT)) return; 3366 3367 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3368 unsigned nparams = FTP->getNumArgs(); 3369 assert(FD->getNumParams() == nparams); 3370 3371 if (nparams > 3) { 3372 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3373 FD->setInvalidDecl(true); 3374 nparams = 3; 3375 } 3376 3377 // FIXME: a lot of the following diagnostics would be improved 3378 // if we had some location information about types. 3379 3380 QualType CharPP = 3381 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3382 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3383 3384 for (unsigned i = 0; i < nparams; ++i) { 3385 QualType AT = FTP->getArgType(i); 3386 3387 bool mismatch = true; 3388 3389 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3390 mismatch = false; 3391 else if (Expected[i] == CharPP) { 3392 // As an extension, the following forms are okay: 3393 // char const ** 3394 // char const * const * 3395 // char * const * 3396 3397 QualifierCollector qs; 3398 const PointerType* PT; 3399 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3400 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3401 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3402 qs.removeConst(); 3403 mismatch = !qs.empty(); 3404 } 3405 } 3406 3407 if (mismatch) { 3408 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3409 // TODO: suggest replacing given type with expected type 3410 FD->setInvalidDecl(true); 3411 } 3412 } 3413 3414 if (nparams == 1 && !FD->isInvalidDecl()) { 3415 Diag(FD->getLocation(), diag::warn_main_one_arg); 3416 } 3417} 3418 3419bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3420 // FIXME: Need strict checking. In C89, we need to check for 3421 // any assignment, increment, decrement, function-calls, or 3422 // commas outside of a sizeof. In C99, it's the same list, 3423 // except that the aforementioned are allowed in unevaluated 3424 // expressions. Everything else falls under the 3425 // "may accept other forms of constant expressions" exception. 3426 // (We never end up here for C++, so the constant expression 3427 // rules there don't matter.) 3428 if (Init->isConstantInitializer(Context)) 3429 return false; 3430 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3431 << Init->getSourceRange(); 3432 return true; 3433} 3434 3435void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3436 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3437} 3438 3439/// AddInitializerToDecl - Adds the initializer Init to the 3440/// declaration dcl. If DirectInit is true, this is C++ direct 3441/// initialization rather than copy initialization. 3442void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3443 Decl *RealDecl = dcl.getAs<Decl>(); 3444 // If there is no declaration, there was an error parsing it. Just ignore 3445 // the initializer. 3446 if (RealDecl == 0) 3447 return; 3448 3449 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3450 // With declarators parsed the way they are, the parser cannot 3451 // distinguish between a normal initializer and a pure-specifier. 3452 // Thus this grotesque test. 3453 IntegerLiteral *IL; 3454 Expr *Init = static_cast<Expr *>(init.get()); 3455 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3456 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3457 CheckPureMethod(Method, Init->getSourceRange()); 3458 else { 3459 Diag(Method->getLocation(), diag::err_member_function_initialization) 3460 << Method->getDeclName() << Init->getSourceRange(); 3461 Method->setInvalidDecl(); 3462 } 3463 return; 3464 } 3465 3466 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3467 if (!VDecl) { 3468 if (getLangOptions().CPlusPlus && 3469 RealDecl->getLexicalDeclContext()->isRecord() && 3470 isa<NamedDecl>(RealDecl)) 3471 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3472 << cast<NamedDecl>(RealDecl)->getDeclName(); 3473 else 3474 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3475 RealDecl->setInvalidDecl(); 3476 return; 3477 } 3478 3479 // A definition must end up with a complete type, which means it must be 3480 // complete with the restriction that an array type might be completed by the 3481 // initializer; note that later code assumes this restriction. 3482 QualType BaseDeclType = VDecl->getType(); 3483 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3484 BaseDeclType = Array->getElementType(); 3485 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3486 diag::err_typecheck_decl_incomplete_type)) { 3487 RealDecl->setInvalidDecl(); 3488 return; 3489 } 3490 3491 // The variable can not have an abstract class type. 3492 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3493 diag::err_abstract_type_in_decl, 3494 AbstractVariableType)) 3495 VDecl->setInvalidDecl(); 3496 3497 const VarDecl *Def = 0; 3498 if (VDecl->getDefinition(Def)) { 3499 Diag(VDecl->getLocation(), diag::err_redefinition) 3500 << VDecl->getDeclName(); 3501 Diag(Def->getLocation(), diag::note_previous_definition); 3502 VDecl->setInvalidDecl(); 3503 return; 3504 } 3505 3506 // Take ownership of the expression, now that we're sure we have somewhere 3507 // to put it. 3508 Expr *Init = init.takeAs<Expr>(); 3509 assert(Init && "missing initializer"); 3510 3511 // Capture the variable that is being initialized and the style of 3512 // initialization. 3513 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3514 3515 // FIXME: Poor source location information. 3516 InitializationKind Kind 3517 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3518 Init->getLocStart(), 3519 Init->getLocEnd()) 3520 : InitializationKind::CreateCopy(VDecl->getLocation(), 3521 Init->getLocStart()); 3522 3523 // Get the decls type and save a reference for later, since 3524 // CheckInitializerTypes may change it. 3525 QualType DclT = VDecl->getType(), SavT = DclT; 3526 if (VDecl->isBlockVarDecl()) { 3527 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3528 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3529 VDecl->setInvalidDecl(); 3530 } else if (!VDecl->isInvalidDecl()) { 3531 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3532 if (InitSeq) { 3533 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3534 MultiExprArg(*this, (void**)&Init, 1), 3535 &DclT); 3536 if (Result.isInvalid()) { 3537 VDecl->setInvalidDecl(); 3538 return; 3539 } 3540 3541 Init = Result.takeAs<Expr>(); 3542 } else { 3543 InitSeq.Diagnose(*this, Entity, Kind, &Init, 1); 3544 VDecl->setInvalidDecl(); 3545 return; 3546 } 3547 3548 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3549 // Don't check invalid declarations to avoid emitting useless diagnostics. 3550 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3551 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3552 CheckForConstantInitializer(Init, DclT); 3553 } 3554 } 3555 } else if (VDecl->isStaticDataMember() && 3556 VDecl->getLexicalDeclContext()->isRecord()) { 3557 // This is an in-class initialization for a static data member, e.g., 3558 // 3559 // struct S { 3560 // static const int value = 17; 3561 // }; 3562 3563 // Attach the initializer 3564 VDecl->setInit(Context, Init); 3565 3566 // C++ [class.mem]p4: 3567 // A member-declarator can contain a constant-initializer only 3568 // if it declares a static member (9.4) of const integral or 3569 // const enumeration type, see 9.4.2. 3570 QualType T = VDecl->getType(); 3571 if (!T->isDependentType() && 3572 (!Context.getCanonicalType(T).isConstQualified() || 3573 !T->isIntegralType())) { 3574 Diag(VDecl->getLocation(), diag::err_member_initialization) 3575 << VDecl->getDeclName() << Init->getSourceRange(); 3576 VDecl->setInvalidDecl(); 3577 } else { 3578 // C++ [class.static.data]p4: 3579 // If a static data member is of const integral or const 3580 // enumeration type, its declaration in the class definition 3581 // can specify a constant-initializer which shall be an 3582 // integral constant expression (5.19). 3583 if (!Init->isTypeDependent() && 3584 !Init->getType()->isIntegralType()) { 3585 // We have a non-dependent, non-integral or enumeration type. 3586 Diag(Init->getSourceRange().getBegin(), 3587 diag::err_in_class_initializer_non_integral_type) 3588 << Init->getType() << Init->getSourceRange(); 3589 VDecl->setInvalidDecl(); 3590 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3591 // Check whether the expression is a constant expression. 3592 llvm::APSInt Value; 3593 SourceLocation Loc; 3594 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3595 Diag(Loc, diag::err_in_class_initializer_non_constant) 3596 << Init->getSourceRange(); 3597 VDecl->setInvalidDecl(); 3598 } else if (!VDecl->getType()->isDependentType()) 3599 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3600 } 3601 } 3602 } else if (VDecl->isFileVarDecl()) { 3603 if (VDecl->getStorageClass() == VarDecl::Extern) 3604 Diag(VDecl->getLocation(), diag::warn_extern_init); 3605 if (!VDecl->isInvalidDecl()) 3606 if (CheckInitializerTypes(Init, DclT, Entity, Kind)) 3607 VDecl->setInvalidDecl(); 3608 3609 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3610 // Don't check invalid declarations to avoid emitting useless diagnostics. 3611 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3612 // C99 6.7.8p4. All file scoped initializers need to be constant. 3613 CheckForConstantInitializer(Init, DclT); 3614 } 3615 } 3616 // If the type changed, it means we had an incomplete type that was 3617 // completed by the initializer. For example: 3618 // int ary[] = { 1, 3, 5 }; 3619 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3620 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3621 VDecl->setType(DclT); 3622 Init->setType(DclT); 3623 } 3624 3625 Init = MaybeCreateCXXExprWithTemporaries(Init); 3626 // Attach the initializer to the decl. 3627 VDecl->setInit(Context, Init); 3628 3629 // If the previous declaration of VDecl was a tentative definition, 3630 // remove it from the set of tentative definitions. 3631 if (VDecl->getPreviousDeclaration() && 3632 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3633 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3634 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3635 } 3636 3637 return; 3638} 3639 3640void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3641 bool TypeContainsUndeducedAuto) { 3642 Decl *RealDecl = dcl.getAs<Decl>(); 3643 3644 // If there is no declaration, there was an error parsing it. Just ignore it. 3645 if (RealDecl == 0) 3646 return; 3647 3648 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3649 QualType Type = Var->getType(); 3650 3651 // Record tentative definitions. 3652 if (Var->isTentativeDefinition(Context)) { 3653 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3654 InsertPair = 3655 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3656 3657 // Keep the latest definition in the map. If we see 'int i; int i;' we 3658 // want the second one in the map. 3659 InsertPair.first->second = Var; 3660 3661 // However, for the list, we don't care about the order, just make sure 3662 // that there are no dupes for a given declaration name. 3663 if (InsertPair.second) 3664 TentativeDefinitionList.push_back(Var->getDeclName()); 3665 } 3666 3667 // C++ [dcl.init.ref]p3: 3668 // The initializer can be omitted for a reference only in a 3669 // parameter declaration (8.3.5), in the declaration of a 3670 // function return type, in the declaration of a class member 3671 // within its class declaration (9.2), and where the extern 3672 // specifier is explicitly used. 3673 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3674 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3675 << Var->getDeclName() 3676 << SourceRange(Var->getLocation(), Var->getLocation()); 3677 Var->setInvalidDecl(); 3678 return; 3679 } 3680 3681 // C++0x [dcl.spec.auto]p3 3682 if (TypeContainsUndeducedAuto) { 3683 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3684 << Var->getDeclName() << Type; 3685 Var->setInvalidDecl(); 3686 return; 3687 } 3688 3689 // An array without size is an incomplete type, and there are no special 3690 // rules in C++ to make such a definition acceptable. 3691 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3692 !Var->hasExternalStorage()) { 3693 Diag(Var->getLocation(), 3694 diag::err_typecheck_incomplete_array_needs_initializer); 3695 Var->setInvalidDecl(); 3696 return; 3697 } 3698 3699 // C++ [temp.expl.spec]p15: 3700 // An explicit specialization of a static data member of a template is a 3701 // definition if the declaration includes an initializer; otherwise, it 3702 // is a declaration. 3703 if (Var->isStaticDataMember() && 3704 Var->getInstantiatedFromStaticDataMember() && 3705 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3706 return; 3707 3708 // C++ [dcl.init]p9: 3709 // If no initializer is specified for an object, and the object 3710 // is of (possibly cv-qualified) non-POD class type (or array 3711 // thereof), the object shall be default-initialized; if the 3712 // object is of const-qualified type, the underlying class type 3713 // shall have a user-declared default constructor. 3714 // 3715 // FIXME: Diagnose the "user-declared default constructor" bit. 3716 if (getLangOptions().CPlusPlus) { 3717 QualType InitType = Type; 3718 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3719 InitType = Context.getBaseElementType(Array); 3720 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3721 InitType->isRecordType() && !InitType->isDependentType()) { 3722 if (!RequireCompleteType(Var->getLocation(), InitType, 3723 diag::err_invalid_incomplete_type_use)) { 3724 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3725 3726 CXXConstructorDecl *Constructor 3727 = PerformInitializationByConstructor(InitType, 3728 MultiExprArg(*this, 0, 0), 3729 Var->getLocation(), 3730 SourceRange(Var->getLocation(), 3731 Var->getLocation()), 3732 Var->getDeclName(), 3733 InitializationKind::CreateDefault(Var->getLocation()), 3734 ConstructorArgs); 3735 3736 // FIXME: Location info for the variable initialization? 3737 if (!Constructor) 3738 Var->setInvalidDecl(); 3739 else { 3740 // FIXME: Cope with initialization of arrays 3741 if (!Constructor->isTrivial() && 3742 InitializeVarWithConstructor(Var, Constructor, 3743 move_arg(ConstructorArgs))) 3744 Var->setInvalidDecl(); 3745 3746 FinalizeVarWithDestructor(Var, InitType); 3747 } 3748 } else { 3749 Var->setInvalidDecl(); 3750 } 3751 } 3752 3753 // The variable can not have an abstract class type. 3754 if (RequireNonAbstractType(Var->getLocation(), Type, 3755 diag::err_abstract_type_in_decl, 3756 AbstractVariableType)) 3757 Var->setInvalidDecl(); 3758 } 3759 3760#if 0 3761 // FIXME: Temporarily disabled because we are not properly parsing 3762 // linkage specifications on declarations, e.g., 3763 // 3764 // extern "C" const CGPoint CGPointerZero; 3765 // 3766 // C++ [dcl.init]p9: 3767 // 3768 // If no initializer is specified for an object, and the 3769 // object is of (possibly cv-qualified) non-POD class type (or 3770 // array thereof), the object shall be default-initialized; if 3771 // the object is of const-qualified type, the underlying class 3772 // type shall have a user-declared default 3773 // constructor. Otherwise, if no initializer is specified for 3774 // an object, the object and its subobjects, if any, have an 3775 // indeterminate initial value; if the object or any of its 3776 // subobjects are of const-qualified type, the program is 3777 // ill-formed. 3778 // 3779 // This isn't technically an error in C, so we don't diagnose it. 3780 // 3781 // FIXME: Actually perform the POD/user-defined default 3782 // constructor check. 3783 if (getLangOptions().CPlusPlus && 3784 Context.getCanonicalType(Type).isConstQualified() && 3785 !Var->hasExternalStorage()) 3786 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3787 << Var->getName() 3788 << SourceRange(Var->getLocation(), Var->getLocation()); 3789#endif 3790 } 3791} 3792 3793Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3794 DeclPtrTy *Group, 3795 unsigned NumDecls) { 3796 llvm::SmallVector<Decl*, 8> Decls; 3797 3798 if (DS.isTypeSpecOwned()) 3799 Decls.push_back((Decl*)DS.getTypeRep()); 3800 3801 for (unsigned i = 0; i != NumDecls; ++i) 3802 if (Decl *D = Group[i].getAs<Decl>()) 3803 Decls.push_back(D); 3804 3805 // Perform semantic analysis that depends on having fully processed both 3806 // the declarator and initializer. 3807 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3808 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3809 if (!IDecl) 3810 continue; 3811 QualType T = IDecl->getType(); 3812 3813 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3814 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3815 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3816 if (T->isDependentType()) { 3817 // If T is dependent, we should not require a complete type. 3818 // (RequireCompleteType shouldn't be called with dependent types.) 3819 // But we still can at least check if we've got an array of unspecified 3820 // size without an initializer. 3821 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3822 !IDecl->getInit()) { 3823 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3824 << T; 3825 IDecl->setInvalidDecl(); 3826 } 3827 } else if (!IDecl->isInvalidDecl()) { 3828 // If T is an incomplete array type with an initializer list that is 3829 // dependent on something, its size has not been fixed. We could attempt 3830 // to fix the size for such arrays, but we would still have to check 3831 // here for initializers containing a C++0x vararg expansion, e.g. 3832 // template <typename... Args> void f(Args... args) { 3833 // int vals[] = { args }; 3834 // } 3835 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3836 Expr *Init = IDecl->getInit(); 3837 if (IAT && Init && 3838 (Init->isTypeDependent() || Init->isValueDependent())) { 3839 // Check that the member type of the array is complete, at least. 3840 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3841 diag::err_typecheck_decl_incomplete_type)) 3842 IDecl->setInvalidDecl(); 3843 } else if (RequireCompleteType(IDecl->getLocation(), T, 3844 diag::err_typecheck_decl_incomplete_type)) 3845 IDecl->setInvalidDecl(); 3846 } 3847 } 3848 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3849 // object that has file scope without an initializer, and without a 3850 // storage-class specifier or with the storage-class specifier "static", 3851 // constitutes a tentative definition. Note: A tentative definition with 3852 // external linkage is valid (C99 6.2.2p5). 3853 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3854 if (const IncompleteArrayType *ArrayT 3855 = Context.getAsIncompleteArrayType(T)) { 3856 if (RequireCompleteType(IDecl->getLocation(), 3857 ArrayT->getElementType(), 3858 diag::err_illegal_decl_array_incomplete_type)) 3859 IDecl->setInvalidDecl(); 3860 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3861 // C99 6.9.2p3: If the declaration of an identifier for an object is 3862 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3863 // declared type shall not be an incomplete type. 3864 // NOTE: code such as the following 3865 // static struct s; 3866 // struct s { int a; }; 3867 // is accepted by gcc. Hence here we issue a warning instead of 3868 // an error and we do not invalidate the static declaration. 3869 // NOTE: to avoid multiple warnings, only check the first declaration. 3870 if (IDecl->getPreviousDeclaration() == 0) 3871 RequireCompleteType(IDecl->getLocation(), T, 3872 diag::ext_typecheck_decl_incomplete_type); 3873 } 3874 } 3875 } 3876 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3877 Decls.data(), Decls.size())); 3878} 3879 3880 3881/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3882/// to introduce parameters into function prototype scope. 3883Sema::DeclPtrTy 3884Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3885 const DeclSpec &DS = D.getDeclSpec(); 3886 3887 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3888 VarDecl::StorageClass StorageClass = VarDecl::None; 3889 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3890 StorageClass = VarDecl::Register; 3891 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3892 Diag(DS.getStorageClassSpecLoc(), 3893 diag::err_invalid_storage_class_in_func_decl); 3894 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3895 } 3896 3897 if (D.getDeclSpec().isThreadSpecified()) 3898 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3899 3900 DiagnoseFunctionSpecifiers(D); 3901 3902 // Check that there are no default arguments inside the type of this 3903 // parameter (C++ only). 3904 if (getLangOptions().CPlusPlus) 3905 CheckExtraCXXDefaultArguments(D); 3906 3907 TypeSourceInfo *TInfo = 0; 3908 TagDecl *OwnedDecl = 0; 3909 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3910 3911 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3912 // C++ [dcl.fct]p6: 3913 // Types shall not be defined in return or parameter types. 3914 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3915 << Context.getTypeDeclType(OwnedDecl); 3916 } 3917 3918 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3919 // Can this happen for params? We already checked that they don't conflict 3920 // among each other. Here they can only shadow globals, which is ok. 3921 IdentifierInfo *II = D.getIdentifier(); 3922 if (II) { 3923 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3924 if (PrevDecl->isTemplateParameter()) { 3925 // Maybe we will complain about the shadowed template parameter. 3926 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3927 // Just pretend that we didn't see the previous declaration. 3928 PrevDecl = 0; 3929 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3930 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3931 3932 // Recover by removing the name 3933 II = 0; 3934 D.SetIdentifier(0, D.getIdentifierLoc()); 3935 } 3936 } 3937 } 3938 3939 // Parameters can not be abstract class types. 3940 // For record types, this is done by the AbstractClassUsageDiagnoser once 3941 // the class has been completely parsed. 3942 if (!CurContext->isRecord() && 3943 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3944 diag::err_abstract_type_in_decl, 3945 AbstractParamType)) 3946 D.setInvalidType(true); 3947 3948 QualType T = adjustParameterType(parmDeclType); 3949 3950 ParmVarDecl *New 3951 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3952 T, TInfo, StorageClass, 0); 3953 3954 if (D.isInvalidType()) 3955 New->setInvalidDecl(); 3956 3957 // Parameter declarators cannot be interface types. All ObjC objects are 3958 // passed by reference. 3959 if (T->isObjCInterfaceType()) { 3960 Diag(D.getIdentifierLoc(), 3961 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3962 New->setInvalidDecl(); 3963 } 3964 3965 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3966 if (D.getCXXScopeSpec().isSet()) { 3967 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3968 << D.getCXXScopeSpec().getRange(); 3969 New->setInvalidDecl(); 3970 } 3971 3972 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3973 // duration shall not be qualified by an address-space qualifier." 3974 // Since all parameters have automatic store duration, they can not have 3975 // an address space. 3976 if (T.getAddressSpace() != 0) { 3977 Diag(D.getIdentifierLoc(), 3978 diag::err_arg_with_address_space); 3979 New->setInvalidDecl(); 3980 } 3981 3982 3983 // Add the parameter declaration into this scope. 3984 S->AddDecl(DeclPtrTy::make(New)); 3985 if (II) 3986 IdResolver.AddDecl(New); 3987 3988 ProcessDeclAttributes(S, New, D); 3989 3990 if (New->hasAttr<BlocksAttr>()) { 3991 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3992 } 3993 return DeclPtrTy::make(New); 3994} 3995 3996void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3997 SourceLocation LocAfterDecls) { 3998 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3999 "Not a function declarator!"); 4000 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4001 4002 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4003 // for a K&R function. 4004 if (!FTI.hasPrototype) { 4005 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4006 --i; 4007 if (FTI.ArgInfo[i].Param == 0) { 4008 llvm::SmallString<256> Code; 4009 llvm::raw_svector_ostream(Code) << " int " 4010 << FTI.ArgInfo[i].Ident->getName() 4011 << ";\n"; 4012 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4013 << FTI.ArgInfo[i].Ident 4014 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4015 4016 // Implicitly declare the argument as type 'int' for lack of a better 4017 // type. 4018 DeclSpec DS; 4019 const char* PrevSpec; // unused 4020 unsigned DiagID; // unused 4021 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4022 PrevSpec, DiagID); 4023 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4024 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4025 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4026 } 4027 } 4028 } 4029} 4030 4031Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4032 Declarator &D) { 4033 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4034 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4035 "Not a function declarator!"); 4036 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4037 4038 if (FTI.hasPrototype) { 4039 // FIXME: Diagnose arguments without names in C. 4040 } 4041 4042 Scope *ParentScope = FnBodyScope->getParent(); 4043 4044 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4045 MultiTemplateParamsArg(*this), 4046 /*IsFunctionDefinition=*/true); 4047 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4048} 4049 4050static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4051 // Don't warn about invalid declarations. 4052 if (FD->isInvalidDecl()) 4053 return false; 4054 4055 // Or declarations that aren't global. 4056 if (!FD->isGlobal()) 4057 return false; 4058 4059 // Don't warn about C++ member functions. 4060 if (isa<CXXMethodDecl>(FD)) 4061 return false; 4062 4063 // Don't warn about 'main'. 4064 if (FD->isMain()) 4065 return false; 4066 4067 // Don't warn about inline functions. 4068 if (FD->isInlineSpecified()) 4069 return false; 4070 4071 // Don't warn about function templates. 4072 if (FD->getDescribedFunctionTemplate()) 4073 return false; 4074 4075 // Don't warn about function template specializations. 4076 if (FD->isFunctionTemplateSpecialization()) 4077 return false; 4078 4079 bool MissingPrototype = true; 4080 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4081 Prev; Prev = Prev->getPreviousDeclaration()) { 4082 // Ignore any declarations that occur in function or method 4083 // scope, because they aren't visible from the header. 4084 if (Prev->getDeclContext()->isFunctionOrMethod()) 4085 continue; 4086 4087 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4088 break; 4089 } 4090 4091 return MissingPrototype; 4092} 4093 4094Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4095 // Clear the last template instantiation error context. 4096 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4097 4098 if (!D) 4099 return D; 4100 FunctionDecl *FD = 0; 4101 4102 if (FunctionTemplateDecl *FunTmpl 4103 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4104 FD = FunTmpl->getTemplatedDecl(); 4105 else 4106 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4107 4108 CurFunctionNeedsScopeChecking = false; 4109 4110 // See if this is a redefinition. 4111 const FunctionDecl *Definition; 4112 if (FD->getBody(Definition)) { 4113 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4114 Diag(Definition->getLocation(), diag::note_previous_definition); 4115 } 4116 4117 // Builtin functions cannot be defined. 4118 if (unsigned BuiltinID = FD->getBuiltinID()) { 4119 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4120 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4121 FD->setInvalidDecl(); 4122 } 4123 } 4124 4125 // The return type of a function definition must be complete 4126 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4127 QualType ResultType = FD->getResultType(); 4128 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4129 !FD->isInvalidDecl() && 4130 RequireCompleteType(FD->getLocation(), ResultType, 4131 diag::err_func_def_incomplete_result)) 4132 FD->setInvalidDecl(); 4133 4134 // GNU warning -Wmissing-prototypes: 4135 // Warn if a global function is defined without a previous 4136 // prototype declaration. This warning is issued even if the 4137 // definition itself provides a prototype. The aim is to detect 4138 // global functions that fail to be declared in header files. 4139 if (ShouldWarnAboutMissingPrototype(FD)) 4140 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4141 4142 if (FnBodyScope) 4143 PushDeclContext(FnBodyScope, FD); 4144 4145 // Check the validity of our function parameters 4146 CheckParmsForFunctionDef(FD); 4147 4148 // Introduce our parameters into the function scope 4149 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4150 ParmVarDecl *Param = FD->getParamDecl(p); 4151 Param->setOwningFunction(FD); 4152 4153 // If this has an identifier, add it to the scope stack. 4154 if (Param->getIdentifier() && FnBodyScope) 4155 PushOnScopeChains(Param, FnBodyScope); 4156 } 4157 4158 // Checking attributes of current function definition 4159 // dllimport attribute. 4160 if (FD->getAttr<DLLImportAttr>() && 4161 (!FD->getAttr<DLLExportAttr>())) { 4162 // dllimport attribute cannot be applied to definition. 4163 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4164 Diag(FD->getLocation(), 4165 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4166 << "dllimport"; 4167 FD->setInvalidDecl(); 4168 return DeclPtrTy::make(FD); 4169 } else { 4170 // If a symbol previously declared dllimport is later defined, the 4171 // attribute is ignored in subsequent references, and a warning is 4172 // emitted. 4173 Diag(FD->getLocation(), 4174 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4175 << FD->getNameAsCString() << "dllimport"; 4176 } 4177 } 4178 return DeclPtrTy::make(FD); 4179} 4180 4181Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4182 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4183} 4184 4185Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4186 bool IsInstantiation) { 4187 Decl *dcl = D.getAs<Decl>(); 4188 Stmt *Body = BodyArg.takeAs<Stmt>(); 4189 4190 FunctionDecl *FD = 0; 4191 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4192 if (FunTmpl) 4193 FD = FunTmpl->getTemplatedDecl(); 4194 else 4195 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4196 4197 if (FD) { 4198 FD->setBody(Body); 4199 if (FD->isMain()) 4200 // C and C++ allow for main to automagically return 0. 4201 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4202 FD->setHasImplicitReturnZero(true); 4203 else 4204 CheckFallThroughForFunctionDef(FD, Body); 4205 4206 if (!FD->isInvalidDecl()) 4207 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4208 4209 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4210 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4211 4212 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4213 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4214 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4215 MD->setBody(Body); 4216 CheckFallThroughForFunctionDef(MD, Body); 4217 MD->setEndLoc(Body->getLocEnd()); 4218 4219 if (!MD->isInvalidDecl()) 4220 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4221 } else { 4222 Body->Destroy(Context); 4223 return DeclPtrTy(); 4224 } 4225 if (!IsInstantiation) 4226 PopDeclContext(); 4227 4228 // Verify and clean out per-function state. 4229 4230 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4231 4232 // Check goto/label use. 4233 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4234 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4235 LabelStmt *L = I->second; 4236 4237 // Verify that we have no forward references left. If so, there was a goto 4238 // or address of a label taken, but no definition of it. Label fwd 4239 // definitions are indicated with a null substmt. 4240 if (L->getSubStmt() != 0) 4241 continue; 4242 4243 // Emit error. 4244 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4245 4246 // At this point, we have gotos that use the bogus label. Stitch it into 4247 // the function body so that they aren't leaked and that the AST is well 4248 // formed. 4249 if (Body == 0) { 4250 // The whole function wasn't parsed correctly, just delete this. 4251 L->Destroy(Context); 4252 continue; 4253 } 4254 4255 // Otherwise, the body is valid: we want to stitch the label decl into the 4256 // function somewhere so that it is properly owned and so that the goto 4257 // has a valid target. Do this by creating a new compound stmt with the 4258 // label in it. 4259 4260 // Give the label a sub-statement. 4261 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4262 4263 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4264 cast<CXXTryStmt>(Body)->getTryBlock() : 4265 cast<CompoundStmt>(Body); 4266 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4267 Elements.push_back(L); 4268 Compound->setStmts(Context, &Elements[0], Elements.size()); 4269 } 4270 FunctionLabelMap.clear(); 4271 4272 if (!Body) return D; 4273 4274 // Verify that that gotos and switch cases don't jump into scopes illegally. 4275 if (CurFunctionNeedsScopeChecking) 4276 DiagnoseInvalidJumps(Body); 4277 4278 // C++ constructors that have function-try-blocks can't have return 4279 // statements in the handlers of that block. (C++ [except.handle]p14) 4280 // Verify this. 4281 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4282 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4283 4284 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4285 MarkBaseAndMemberDestructorsReferenced(Destructor); 4286 4287 // If any errors have occurred, clear out any temporaries that may have 4288 // been leftover. This ensures that these temporaries won't be picked up for 4289 // deletion in some later function. 4290 if (PP.getDiagnostics().hasErrorOccurred()) 4291 ExprTemporaries.clear(); 4292 4293 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4294 return D; 4295} 4296 4297/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4298/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4299NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4300 IdentifierInfo &II, Scope *S) { 4301 // Before we produce a declaration for an implicitly defined 4302 // function, see whether there was a locally-scoped declaration of 4303 // this name as a function or variable. If so, use that 4304 // (non-visible) declaration, and complain about it. 4305 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4306 = LocallyScopedExternalDecls.find(&II); 4307 if (Pos != LocallyScopedExternalDecls.end()) { 4308 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4309 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4310 return Pos->second; 4311 } 4312 4313 // Extension in C99. Legal in C90, but warn about it. 4314 if (II.getName().startswith("__builtin_")) 4315 Diag(Loc, diag::warn_builtin_unknown) << &II; 4316 else if (getLangOptions().C99) 4317 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4318 else 4319 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4320 4321 // Set a Declarator for the implicit definition: int foo(); 4322 const char *Dummy; 4323 DeclSpec DS; 4324 unsigned DiagID; 4325 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4326 Error = Error; // Silence warning. 4327 assert(!Error && "Error setting up implicit decl!"); 4328 Declarator D(DS, Declarator::BlockContext); 4329 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4330 0, 0, false, SourceLocation(), 4331 false, 0,0,0, Loc, Loc, D), 4332 SourceLocation()); 4333 D.SetIdentifier(&II, Loc); 4334 4335 // Insert this function into translation-unit scope. 4336 4337 DeclContext *PrevDC = CurContext; 4338 CurContext = Context.getTranslationUnitDecl(); 4339 4340 FunctionDecl *FD = 4341 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4342 FD->setImplicit(); 4343 4344 CurContext = PrevDC; 4345 4346 AddKnownFunctionAttributes(FD); 4347 4348 return FD; 4349} 4350 4351/// \brief Adds any function attributes that we know a priori based on 4352/// the declaration of this function. 4353/// 4354/// These attributes can apply both to implicitly-declared builtins 4355/// (like __builtin___printf_chk) or to library-declared functions 4356/// like NSLog or printf. 4357void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4358 if (FD->isInvalidDecl()) 4359 return; 4360 4361 // If this is a built-in function, map its builtin attributes to 4362 // actual attributes. 4363 if (unsigned BuiltinID = FD->getBuiltinID()) { 4364 // Handle printf-formatting attributes. 4365 unsigned FormatIdx; 4366 bool HasVAListArg; 4367 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4368 if (!FD->getAttr<FormatAttr>()) 4369 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4370 HasVAListArg ? 0 : FormatIdx + 2)); 4371 } 4372 4373 // Mark const if we don't care about errno and that is the only 4374 // thing preventing the function from being const. This allows 4375 // IRgen to use LLVM intrinsics for such functions. 4376 if (!getLangOptions().MathErrno && 4377 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4378 if (!FD->getAttr<ConstAttr>()) 4379 FD->addAttr(::new (Context) ConstAttr()); 4380 } 4381 4382 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4383 FD->addAttr(::new (Context) NoReturnAttr()); 4384 } 4385 4386 IdentifierInfo *Name = FD->getIdentifier(); 4387 if (!Name) 4388 return; 4389 if ((!getLangOptions().CPlusPlus && 4390 FD->getDeclContext()->isTranslationUnit()) || 4391 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4392 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4393 LinkageSpecDecl::lang_c)) { 4394 // Okay: this could be a libc/libm/Objective-C function we know 4395 // about. 4396 } else 4397 return; 4398 4399 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4400 // FIXME: NSLog and NSLogv should be target specific 4401 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4402 // FIXME: We known better than our headers. 4403 const_cast<FormatAttr *>(Format)->setType("printf"); 4404 } else 4405 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4406 Name->isStr("NSLogv") ? 0 : 2)); 4407 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4408 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4409 // target-specific builtins, perhaps? 4410 if (!FD->getAttr<FormatAttr>()) 4411 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4412 Name->isStr("vasprintf") ? 0 : 3)); 4413 } 4414} 4415 4416TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4417 TypeSourceInfo *TInfo) { 4418 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4419 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4420 4421 if (!TInfo) { 4422 assert(D.isInvalidType() && "no declarator info for valid type"); 4423 TInfo = Context.getTrivialTypeSourceInfo(T); 4424 } 4425 4426 // Scope manipulation handled by caller. 4427 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4428 D.getIdentifierLoc(), 4429 D.getIdentifier(), 4430 TInfo); 4431 4432 if (const TagType *TT = T->getAs<TagType>()) { 4433 TagDecl *TD = TT->getDecl(); 4434 4435 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4436 // keep track of the TypedefDecl. 4437 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4438 TD->setTypedefForAnonDecl(NewTD); 4439 } 4440 4441 if (D.isInvalidType()) 4442 NewTD->setInvalidDecl(); 4443 return NewTD; 4444} 4445 4446 4447/// \brief Determine whether a tag with a given kind is acceptable 4448/// as a redeclaration of the given tag declaration. 4449/// 4450/// \returns true if the new tag kind is acceptable, false otherwise. 4451bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4452 TagDecl::TagKind NewTag, 4453 SourceLocation NewTagLoc, 4454 const IdentifierInfo &Name) { 4455 // C++ [dcl.type.elab]p3: 4456 // The class-key or enum keyword present in the 4457 // elaborated-type-specifier shall agree in kind with the 4458 // declaration to which the name in theelaborated-type-specifier 4459 // refers. This rule also applies to the form of 4460 // elaborated-type-specifier that declares a class-name or 4461 // friend class since it can be construed as referring to the 4462 // definition of the class. Thus, in any 4463 // elaborated-type-specifier, the enum keyword shall be used to 4464 // refer to an enumeration (7.2), the union class-keyshall be 4465 // used to refer to a union (clause 9), and either the class or 4466 // struct class-key shall be used to refer to a class (clause 9) 4467 // declared using the class or struct class-key. 4468 TagDecl::TagKind OldTag = Previous->getTagKind(); 4469 if (OldTag == NewTag) 4470 return true; 4471 4472 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4473 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4474 // Warn about the struct/class tag mismatch. 4475 bool isTemplate = false; 4476 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4477 isTemplate = Record->getDescribedClassTemplate(); 4478 4479 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4480 << (NewTag == TagDecl::TK_class) 4481 << isTemplate << &Name 4482 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4483 OldTag == TagDecl::TK_class? "class" : "struct"); 4484 Diag(Previous->getLocation(), diag::note_previous_use); 4485 return true; 4486 } 4487 return false; 4488} 4489 4490/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4491/// former case, Name will be non-null. In the later case, Name will be null. 4492/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4493/// reference/declaration/definition of a tag. 4494Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4495 SourceLocation KWLoc, const CXXScopeSpec &SS, 4496 IdentifierInfo *Name, SourceLocation NameLoc, 4497 AttributeList *Attr, AccessSpecifier AS, 4498 MultiTemplateParamsArg TemplateParameterLists, 4499 bool &OwnedDecl, bool &IsDependent) { 4500 // If this is not a definition, it must have a name. 4501 assert((Name != 0 || TUK == TUK_Definition) && 4502 "Nameless record must be a definition!"); 4503 4504 OwnedDecl = false; 4505 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4506 4507 // FIXME: Check explicit specializations more carefully. 4508 bool isExplicitSpecialization = false; 4509 if (TUK != TUK_Reference) { 4510 if (TemplateParameterList *TemplateParams 4511 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4512 (TemplateParameterList**)TemplateParameterLists.get(), 4513 TemplateParameterLists.size(), 4514 isExplicitSpecialization)) { 4515 if (TemplateParams->size() > 0) { 4516 // This is a declaration or definition of a class template (which may 4517 // be a member of another template). 4518 OwnedDecl = false; 4519 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4520 SS, Name, NameLoc, Attr, 4521 TemplateParams, 4522 AS); 4523 TemplateParameterLists.release(); 4524 return Result.get(); 4525 } else { 4526 // The "template<>" header is extraneous. 4527 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4528 << ElaboratedType::getNameForTagKind(Kind) << Name; 4529 isExplicitSpecialization = true; 4530 } 4531 } 4532 4533 TemplateParameterLists.release(); 4534 } 4535 4536 DeclContext *SearchDC = CurContext; 4537 DeclContext *DC = CurContext; 4538 bool isStdBadAlloc = false; 4539 bool Invalid = false; 4540 4541 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4542 : NotForRedeclaration); 4543 4544 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4545 4546 if (Name && SS.isNotEmpty()) { 4547 // We have a nested-name tag ('struct foo::bar'). 4548 4549 // Check for invalid 'foo::'. 4550 if (SS.isInvalid()) { 4551 Name = 0; 4552 goto CreateNewDecl; 4553 } 4554 4555 // If this is a friend or a reference to a class in a dependent 4556 // context, don't try to make a decl for it. 4557 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4558 DC = computeDeclContext(SS, false); 4559 if (!DC) { 4560 IsDependent = true; 4561 return DeclPtrTy(); 4562 } 4563 } 4564 4565 if (RequireCompleteDeclContext(SS)) 4566 return DeclPtrTy::make((Decl *)0); 4567 4568 DC = computeDeclContext(SS, true); 4569 SearchDC = DC; 4570 // Look-up name inside 'foo::'. 4571 LookupQualifiedName(Previous, DC); 4572 4573 if (Previous.isAmbiguous()) 4574 return DeclPtrTy(); 4575 4576 // A tag 'foo::bar' must already exist. 4577 if (Previous.empty()) { 4578 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4579 Name = 0; 4580 Invalid = true; 4581 goto CreateNewDecl; 4582 } 4583 } else if (Name) { 4584 // If this is a named struct, check to see if there was a previous forward 4585 // declaration or definition. 4586 // FIXME: We're looking into outer scopes here, even when we 4587 // shouldn't be. Doing so can result in ambiguities that we 4588 // shouldn't be diagnosing. 4589 LookupName(Previous, S); 4590 4591 // Note: there used to be some attempt at recovery here. 4592 if (Previous.isAmbiguous()) 4593 return DeclPtrTy(); 4594 4595 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4596 // FIXME: This makes sure that we ignore the contexts associated 4597 // with C structs, unions, and enums when looking for a matching 4598 // tag declaration or definition. See the similar lookup tweak 4599 // in Sema::LookupName; is there a better way to deal with this? 4600 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4601 SearchDC = SearchDC->getParent(); 4602 } 4603 } 4604 4605 if (Previous.isSingleResult() && 4606 Previous.getFoundDecl()->isTemplateParameter()) { 4607 // Maybe we will complain about the shadowed template parameter. 4608 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4609 // Just pretend that we didn't see the previous declaration. 4610 Previous.clear(); 4611 } 4612 4613 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4614 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4615 // This is a declaration of or a reference to "std::bad_alloc". 4616 isStdBadAlloc = true; 4617 4618 if (Previous.empty() && StdBadAlloc) { 4619 // std::bad_alloc has been implicitly declared (but made invisible to 4620 // name lookup). Fill in this implicit declaration as the previous 4621 // declaration, so that the declarations get chained appropriately. 4622 Previous.addDecl(StdBadAlloc); 4623 } 4624 } 4625 4626 if (!Previous.empty()) { 4627 assert(Previous.isSingleResult()); 4628 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4629 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4630 // If this is a use of a previous tag, or if the tag is already declared 4631 // in the same scope (so that the definition/declaration completes or 4632 // rementions the tag), reuse the decl. 4633 if (TUK == TUK_Reference || TUK == TUK_Friend || 4634 isDeclInScope(PrevDecl, SearchDC, S)) { 4635 // Make sure that this wasn't declared as an enum and now used as a 4636 // struct or something similar. 4637 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4638 bool SafeToContinue 4639 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4640 Kind != TagDecl::TK_enum); 4641 if (SafeToContinue) 4642 Diag(KWLoc, diag::err_use_with_wrong_tag) 4643 << Name 4644 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4645 PrevTagDecl->getKindName()); 4646 else 4647 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4648 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4649 4650 if (SafeToContinue) 4651 Kind = PrevTagDecl->getTagKind(); 4652 else { 4653 // Recover by making this an anonymous redefinition. 4654 Name = 0; 4655 Previous.clear(); 4656 Invalid = true; 4657 } 4658 } 4659 4660 if (!Invalid) { 4661 // If this is a use, just return the declaration we found. 4662 4663 // FIXME: In the future, return a variant or some other clue 4664 // for the consumer of this Decl to know it doesn't own it. 4665 // For our current ASTs this shouldn't be a problem, but will 4666 // need to be changed with DeclGroups. 4667 if (TUK == TUK_Reference || TUK == TUK_Friend) 4668 return DeclPtrTy::make(PrevTagDecl); 4669 4670 // Diagnose attempts to redefine a tag. 4671 if (TUK == TUK_Definition) { 4672 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4673 // If we're defining a specialization and the previous definition 4674 // is from an implicit instantiation, don't emit an error 4675 // here; we'll catch this in the general case below. 4676 if (!isExplicitSpecialization || 4677 !isa<CXXRecordDecl>(Def) || 4678 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4679 == TSK_ExplicitSpecialization) { 4680 Diag(NameLoc, diag::err_redefinition) << Name; 4681 Diag(Def->getLocation(), diag::note_previous_definition); 4682 // If this is a redefinition, recover by making this 4683 // struct be anonymous, which will make any later 4684 // references get the previous definition. 4685 Name = 0; 4686 Previous.clear(); 4687 Invalid = true; 4688 } 4689 } else { 4690 // If the type is currently being defined, complain 4691 // about a nested redefinition. 4692 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4693 if (Tag->isBeingDefined()) { 4694 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4695 Diag(PrevTagDecl->getLocation(), 4696 diag::note_previous_definition); 4697 Name = 0; 4698 Previous.clear(); 4699 Invalid = true; 4700 } 4701 } 4702 4703 // Okay, this is definition of a previously declared or referenced 4704 // tag PrevDecl. We're going to create a new Decl for it. 4705 } 4706 } 4707 // If we get here we have (another) forward declaration or we 4708 // have a definition. Just create a new decl. 4709 4710 } else { 4711 // If we get here, this is a definition of a new tag type in a nested 4712 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4713 // new decl/type. We set PrevDecl to NULL so that the entities 4714 // have distinct types. 4715 Previous.clear(); 4716 } 4717 // If we get here, we're going to create a new Decl. If PrevDecl 4718 // is non-NULL, it's a definition of the tag declared by 4719 // PrevDecl. If it's NULL, we have a new definition. 4720 } else { 4721 // PrevDecl is a namespace, template, or anything else 4722 // that lives in the IDNS_Tag identifier namespace. 4723 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4724 // The tag name clashes with a namespace name, issue an error and 4725 // recover by making this tag be anonymous. 4726 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4727 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4728 Name = 0; 4729 Previous.clear(); 4730 Invalid = true; 4731 } else { 4732 // The existing declaration isn't relevant to us; we're in a 4733 // new scope, so clear out the previous declaration. 4734 Previous.clear(); 4735 } 4736 } 4737 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4738 // C++ [basic.scope.pdecl]p5: 4739 // -- for an elaborated-type-specifier of the form 4740 // 4741 // class-key identifier 4742 // 4743 // if the elaborated-type-specifier is used in the 4744 // decl-specifier-seq or parameter-declaration-clause of a 4745 // function defined in namespace scope, the identifier is 4746 // declared as a class-name in the namespace that contains 4747 // the declaration; otherwise, except as a friend 4748 // declaration, the identifier is declared in the smallest 4749 // non-class, non-function-prototype scope that contains the 4750 // declaration. 4751 // 4752 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4753 // C structs and unions. 4754 // 4755 // It is an error in C++ to declare (rather than define) an enum 4756 // type, including via an elaborated type specifier. We'll 4757 // diagnose that later; for now, declare the enum in the same 4758 // scope as we would have picked for any other tag type. 4759 // 4760 // GNU C also supports this behavior as part of its incomplete 4761 // enum types extension, while GNU C++ does not. 4762 // 4763 // Find the context where we'll be declaring the tag. 4764 // FIXME: We would like to maintain the current DeclContext as the 4765 // lexical context, 4766 while (SearchDC->isRecord()) 4767 SearchDC = SearchDC->getParent(); 4768 4769 // Find the scope where we'll be declaring the tag. 4770 while (S->isClassScope() || 4771 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4772 ((S->getFlags() & Scope::DeclScope) == 0) || 4773 (S->getEntity() && 4774 ((DeclContext *)S->getEntity())->isTransparentContext())) 4775 S = S->getParent(); 4776 4777 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4778 // C++ [namespace.memdef]p3: 4779 // If a friend declaration in a non-local class first declares a 4780 // class or function, the friend class or function is a member of 4781 // the innermost enclosing namespace. 4782 while (!SearchDC->isFileContext()) 4783 SearchDC = SearchDC->getParent(); 4784 4785 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4786 while (S->getEntity() != SearchDC) 4787 S = S->getParent(); 4788 } 4789 4790CreateNewDecl: 4791 4792 TagDecl *PrevDecl = 0; 4793 if (Previous.isSingleResult()) 4794 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4795 4796 // If there is an identifier, use the location of the identifier as the 4797 // location of the decl, otherwise use the location of the struct/union 4798 // keyword. 4799 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4800 4801 // Otherwise, create a new declaration. If there is a previous 4802 // declaration of the same entity, the two will be linked via 4803 // PrevDecl. 4804 TagDecl *New; 4805 4806 if (Kind == TagDecl::TK_enum) { 4807 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4808 // enum X { A, B, C } D; D should chain to X. 4809 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4810 cast_or_null<EnumDecl>(PrevDecl)); 4811 // If this is an undefined enum, warn. 4812 if (TUK != TUK_Definition && !Invalid) { 4813 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4814 : diag::ext_forward_ref_enum; 4815 Diag(Loc, DK); 4816 } 4817 } else { 4818 // struct/union/class 4819 4820 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4821 // struct X { int A; } D; D should chain to X. 4822 if (getLangOptions().CPlusPlus) { 4823 // FIXME: Look for a way to use RecordDecl for simple structs. 4824 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4825 cast_or_null<CXXRecordDecl>(PrevDecl)); 4826 4827 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4828 StdBadAlloc = cast<CXXRecordDecl>(New); 4829 } else 4830 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4831 cast_or_null<RecordDecl>(PrevDecl)); 4832 } 4833 4834 if (Kind != TagDecl::TK_enum) { 4835 // Handle #pragma pack: if the #pragma pack stack has non-default 4836 // alignment, make up a packed attribute for this decl. These 4837 // attributes are checked when the ASTContext lays out the 4838 // structure. 4839 // 4840 // It is important for implementing the correct semantics that this 4841 // happen here (in act on tag decl). The #pragma pack stack is 4842 // maintained as a result of parser callbacks which can occur at 4843 // many points during the parsing of a struct declaration (because 4844 // the #pragma tokens are effectively skipped over during the 4845 // parsing of the struct). 4846 if (unsigned Alignment = getPragmaPackAlignment()) 4847 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4848 } 4849 4850 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4851 // C++ [dcl.typedef]p3: 4852 // [...] Similarly, in a given scope, a class or enumeration 4853 // shall not be declared with the same name as a typedef-name 4854 // that is declared in that scope and refers to a type other 4855 // than the class or enumeration itself. 4856 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4857 ForRedeclaration); 4858 LookupName(Lookup, S); 4859 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4860 NamedDecl *PrevTypedefNamed = PrevTypedef; 4861 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4862 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4863 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4864 Diag(Loc, diag::err_tag_definition_of_typedef) 4865 << Context.getTypeDeclType(New) 4866 << PrevTypedef->getUnderlyingType(); 4867 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4868 Invalid = true; 4869 } 4870 } 4871 4872 // If this is a specialization of a member class (of a class template), 4873 // check the specialization. 4874 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4875 Invalid = true; 4876 4877 if (Invalid) 4878 New->setInvalidDecl(); 4879 4880 if (Attr) 4881 ProcessDeclAttributeList(S, New, Attr); 4882 4883 // If we're declaring or defining a tag in function prototype scope 4884 // in C, note that this type can only be used within the function. 4885 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4886 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4887 4888 // Set the lexical context. If the tag has a C++ scope specifier, the 4889 // lexical context will be different from the semantic context. 4890 New->setLexicalDeclContext(CurContext); 4891 4892 // Mark this as a friend decl if applicable. 4893 if (TUK == TUK_Friend) 4894 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4895 4896 // Set the access specifier. 4897 if (!Invalid && TUK != TUK_Friend) 4898 SetMemberAccessSpecifier(New, PrevDecl, AS); 4899 4900 if (TUK == TUK_Definition) 4901 New->startDefinition(); 4902 4903 // If this has an identifier, add it to the scope stack. 4904 if (TUK == TUK_Friend) { 4905 // We might be replacing an existing declaration in the lookup tables; 4906 // if so, borrow its access specifier. 4907 if (PrevDecl) 4908 New->setAccess(PrevDecl->getAccess()); 4909 4910 // Friend tag decls are visible in fairly strange ways. 4911 if (!CurContext->isDependentContext()) { 4912 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4913 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4914 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4915 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4916 } 4917 } else if (Name) { 4918 S = getNonFieldDeclScope(S); 4919 PushOnScopeChains(New, S); 4920 } else { 4921 CurContext->addDecl(New); 4922 } 4923 4924 // If this is the C FILE type, notify the AST context. 4925 if (IdentifierInfo *II = New->getIdentifier()) 4926 if (!New->isInvalidDecl() && 4927 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4928 II->isStr("FILE")) 4929 Context.setFILEDecl(New); 4930 4931 OwnedDecl = true; 4932 return DeclPtrTy::make(New); 4933} 4934 4935void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4936 AdjustDeclIfTemplate(TagD); 4937 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4938 4939 // Enter the tag context. 4940 PushDeclContext(S, Tag); 4941 4942 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4943 FieldCollector->StartClass(); 4944 4945 if (Record->getIdentifier()) { 4946 // C++ [class]p2: 4947 // [...] The class-name is also inserted into the scope of the 4948 // class itself; this is known as the injected-class-name. For 4949 // purposes of access checking, the injected-class-name is treated 4950 // as if it were a public member name. 4951 CXXRecordDecl *InjectedClassName 4952 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4953 CurContext, Record->getLocation(), 4954 Record->getIdentifier(), 4955 Record->getTagKeywordLoc(), 4956 Record); 4957 InjectedClassName->setImplicit(); 4958 InjectedClassName->setAccess(AS_public); 4959 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4960 InjectedClassName->setDescribedClassTemplate(Template); 4961 PushOnScopeChains(InjectedClassName, S); 4962 assert(InjectedClassName->isInjectedClassName() && 4963 "Broken injected-class-name"); 4964 } 4965 } 4966} 4967 4968void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4969 SourceLocation RBraceLoc) { 4970 AdjustDeclIfTemplate(TagD); 4971 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4972 Tag->setRBraceLoc(RBraceLoc); 4973 4974 if (isa<CXXRecordDecl>(Tag)) 4975 FieldCollector->FinishClass(); 4976 4977 // Exit this scope of this tag's definition. 4978 PopDeclContext(); 4979 4980 // Notify the consumer that we've defined a tag. 4981 Consumer.HandleTagDeclDefinition(Tag); 4982} 4983 4984// Note that FieldName may be null for anonymous bitfields. 4985bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4986 QualType FieldTy, const Expr *BitWidth, 4987 bool *ZeroWidth) { 4988 // Default to true; that shouldn't confuse checks for emptiness 4989 if (ZeroWidth) 4990 *ZeroWidth = true; 4991 4992 // C99 6.7.2.1p4 - verify the field type. 4993 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4994 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4995 // Handle incomplete types with specific error. 4996 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4997 return true; 4998 if (FieldName) 4999 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5000 << FieldName << FieldTy << BitWidth->getSourceRange(); 5001 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5002 << FieldTy << BitWidth->getSourceRange(); 5003 } 5004 5005 // If the bit-width is type- or value-dependent, don't try to check 5006 // it now. 5007 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5008 return false; 5009 5010 llvm::APSInt Value; 5011 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5012 return true; 5013 5014 if (Value != 0 && ZeroWidth) 5015 *ZeroWidth = false; 5016 5017 // Zero-width bitfield is ok for anonymous field. 5018 if (Value == 0 && FieldName) 5019 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5020 5021 if (Value.isSigned() && Value.isNegative()) { 5022 if (FieldName) 5023 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5024 << FieldName << Value.toString(10); 5025 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5026 << Value.toString(10); 5027 } 5028 5029 if (!FieldTy->isDependentType()) { 5030 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5031 if (Value.getZExtValue() > TypeSize) { 5032 if (FieldName) 5033 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5034 << FieldName << (unsigned)TypeSize; 5035 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5036 << (unsigned)TypeSize; 5037 } 5038 } 5039 5040 return false; 5041} 5042 5043/// ActOnField - Each field of a struct/union/class is passed into this in order 5044/// to create a FieldDecl object for it. 5045Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5046 SourceLocation DeclStart, 5047 Declarator &D, ExprTy *BitfieldWidth) { 5048 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5049 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5050 AS_public); 5051 return DeclPtrTy::make(Res); 5052} 5053 5054/// HandleField - Analyze a field of a C struct or a C++ data member. 5055/// 5056FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5057 SourceLocation DeclStart, 5058 Declarator &D, Expr *BitWidth, 5059 AccessSpecifier AS) { 5060 IdentifierInfo *II = D.getIdentifier(); 5061 SourceLocation Loc = DeclStart; 5062 if (II) Loc = D.getIdentifierLoc(); 5063 5064 TypeSourceInfo *TInfo = 0; 5065 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5066 if (getLangOptions().CPlusPlus) 5067 CheckExtraCXXDefaultArguments(D); 5068 5069 DiagnoseFunctionSpecifiers(D); 5070 5071 if (D.getDeclSpec().isThreadSpecified()) 5072 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5073 5074 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5075 ForRedeclaration); 5076 5077 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5078 // Maybe we will complain about the shadowed template parameter. 5079 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5080 // Just pretend that we didn't see the previous declaration. 5081 PrevDecl = 0; 5082 } 5083 5084 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5085 PrevDecl = 0; 5086 5087 bool Mutable 5088 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5089 SourceLocation TSSL = D.getSourceRange().getBegin(); 5090 FieldDecl *NewFD 5091 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5092 AS, PrevDecl, &D); 5093 if (NewFD->isInvalidDecl() && PrevDecl) { 5094 // Don't introduce NewFD into scope; there's already something 5095 // with the same name in the same scope. 5096 } else if (II) { 5097 PushOnScopeChains(NewFD, S); 5098 } else 5099 Record->addDecl(NewFD); 5100 5101 return NewFD; 5102} 5103 5104/// \brief Build a new FieldDecl and check its well-formedness. 5105/// 5106/// This routine builds a new FieldDecl given the fields name, type, 5107/// record, etc. \p PrevDecl should refer to any previous declaration 5108/// with the same name and in the same scope as the field to be 5109/// created. 5110/// 5111/// \returns a new FieldDecl. 5112/// 5113/// \todo The Declarator argument is a hack. It will be removed once 5114FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5115 TypeSourceInfo *TInfo, 5116 RecordDecl *Record, SourceLocation Loc, 5117 bool Mutable, Expr *BitWidth, 5118 SourceLocation TSSL, 5119 AccessSpecifier AS, NamedDecl *PrevDecl, 5120 Declarator *D) { 5121 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5122 bool InvalidDecl = false; 5123 if (D) InvalidDecl = D->isInvalidType(); 5124 5125 // If we receive a broken type, recover by assuming 'int' and 5126 // marking this declaration as invalid. 5127 if (T.isNull()) { 5128 InvalidDecl = true; 5129 T = Context.IntTy; 5130 } 5131 5132 QualType EltTy = Context.getBaseElementType(T); 5133 if (!EltTy->isDependentType() && 5134 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5135 InvalidDecl = true; 5136 5137 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5138 // than a variably modified type. 5139 if (!InvalidDecl && T->isVariablyModifiedType()) { 5140 bool SizeIsNegative; 5141 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5142 SizeIsNegative); 5143 if (!FixedTy.isNull()) { 5144 Diag(Loc, diag::warn_illegal_constant_array_size); 5145 T = FixedTy; 5146 } else { 5147 if (SizeIsNegative) 5148 Diag(Loc, diag::err_typecheck_negative_array_size); 5149 else 5150 Diag(Loc, diag::err_typecheck_field_variable_size); 5151 InvalidDecl = true; 5152 } 5153 } 5154 5155 // Fields can not have abstract class types 5156 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5157 diag::err_abstract_type_in_decl, 5158 AbstractFieldType)) 5159 InvalidDecl = true; 5160 5161 bool ZeroWidth = false; 5162 // If this is declared as a bit-field, check the bit-field. 5163 if (!InvalidDecl && BitWidth && 5164 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5165 InvalidDecl = true; 5166 DeleteExpr(BitWidth); 5167 BitWidth = 0; 5168 ZeroWidth = false; 5169 } 5170 5171 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5172 BitWidth, Mutable); 5173 if (InvalidDecl) 5174 NewFD->setInvalidDecl(); 5175 5176 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5177 Diag(Loc, diag::err_duplicate_member) << II; 5178 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5179 NewFD->setInvalidDecl(); 5180 } 5181 5182 if (getLangOptions().CPlusPlus) { 5183 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5184 5185 if (!T->isPODType()) 5186 CXXRecord->setPOD(false); 5187 if (!ZeroWidth) 5188 CXXRecord->setEmpty(false); 5189 5190 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5191 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5192 5193 if (!RDecl->hasTrivialConstructor()) 5194 CXXRecord->setHasTrivialConstructor(false); 5195 if (!RDecl->hasTrivialCopyConstructor()) 5196 CXXRecord->setHasTrivialCopyConstructor(false); 5197 if (!RDecl->hasTrivialCopyAssignment()) 5198 CXXRecord->setHasTrivialCopyAssignment(false); 5199 if (!RDecl->hasTrivialDestructor()) 5200 CXXRecord->setHasTrivialDestructor(false); 5201 5202 // C++ 9.5p1: An object of a class with a non-trivial 5203 // constructor, a non-trivial copy constructor, a non-trivial 5204 // destructor, or a non-trivial copy assignment operator 5205 // cannot be a member of a union, nor can an array of such 5206 // objects. 5207 // TODO: C++0x alters this restriction significantly. 5208 if (Record->isUnion()) { 5209 // We check for copy constructors before constructors 5210 // because otherwise we'll never get complaints about 5211 // copy constructors. 5212 5213 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5214 5215 CXXSpecialMember member; 5216 if (!RDecl->hasTrivialCopyConstructor()) 5217 member = CXXCopyConstructor; 5218 else if (!RDecl->hasTrivialConstructor()) 5219 member = CXXDefaultConstructor; 5220 else if (!RDecl->hasTrivialCopyAssignment()) 5221 member = CXXCopyAssignment; 5222 else if (!RDecl->hasTrivialDestructor()) 5223 member = CXXDestructor; 5224 else 5225 member = invalid; 5226 5227 if (member != invalid) { 5228 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5229 DiagnoseNontrivial(RT, member); 5230 NewFD->setInvalidDecl(); 5231 } 5232 } 5233 } 5234 } 5235 5236 // FIXME: We need to pass in the attributes given an AST 5237 // representation, not a parser representation. 5238 if (D) 5239 // FIXME: What to pass instead of TUScope? 5240 ProcessDeclAttributes(TUScope, NewFD, *D); 5241 5242 if (T.isObjCGCWeak()) 5243 Diag(Loc, diag::warn_attribute_weak_on_field); 5244 5245 NewFD->setAccess(AS); 5246 5247 // C++ [dcl.init.aggr]p1: 5248 // An aggregate is an array or a class (clause 9) with [...] no 5249 // private or protected non-static data members (clause 11). 5250 // A POD must be an aggregate. 5251 if (getLangOptions().CPlusPlus && 5252 (AS == AS_private || AS == AS_protected)) { 5253 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5254 CXXRecord->setAggregate(false); 5255 CXXRecord->setPOD(false); 5256 } 5257 5258 return NewFD; 5259} 5260 5261/// DiagnoseNontrivial - Given that a class has a non-trivial 5262/// special member, figure out why. 5263void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5264 QualType QT(T, 0U); 5265 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5266 5267 // Check whether the member was user-declared. 5268 switch (member) { 5269 case CXXDefaultConstructor: 5270 if (RD->hasUserDeclaredConstructor()) { 5271 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5272 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5273 const FunctionDecl *body = 0; 5274 ci->getBody(body); 5275 if (!body || 5276 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5277 SourceLocation CtorLoc = ci->getLocation(); 5278 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5279 return; 5280 } 5281 } 5282 5283 assert(0 && "found no user-declared constructors"); 5284 return; 5285 } 5286 break; 5287 5288 case CXXCopyConstructor: 5289 if (RD->hasUserDeclaredCopyConstructor()) { 5290 SourceLocation CtorLoc = 5291 RD->getCopyConstructor(Context, 0)->getLocation(); 5292 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5293 return; 5294 } 5295 break; 5296 5297 case CXXCopyAssignment: 5298 if (RD->hasUserDeclaredCopyAssignment()) { 5299 // FIXME: this should use the location of the copy 5300 // assignment, not the type. 5301 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5302 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5303 return; 5304 } 5305 break; 5306 5307 case CXXDestructor: 5308 if (RD->hasUserDeclaredDestructor()) { 5309 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5310 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5311 return; 5312 } 5313 break; 5314 } 5315 5316 typedef CXXRecordDecl::base_class_iterator base_iter; 5317 5318 // Virtual bases and members inhibit trivial copying/construction, 5319 // but not trivial destruction. 5320 if (member != CXXDestructor) { 5321 // Check for virtual bases. vbases includes indirect virtual bases, 5322 // so we just iterate through the direct bases. 5323 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5324 if (bi->isVirtual()) { 5325 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5326 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5327 return; 5328 } 5329 5330 // Check for virtual methods. 5331 typedef CXXRecordDecl::method_iterator meth_iter; 5332 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5333 ++mi) { 5334 if (mi->isVirtual()) { 5335 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5336 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5337 return; 5338 } 5339 } 5340 } 5341 5342 bool (CXXRecordDecl::*hasTrivial)() const; 5343 switch (member) { 5344 case CXXDefaultConstructor: 5345 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5346 case CXXCopyConstructor: 5347 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5348 case CXXCopyAssignment: 5349 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5350 case CXXDestructor: 5351 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5352 default: 5353 assert(0 && "unexpected special member"); return; 5354 } 5355 5356 // Check for nontrivial bases (and recurse). 5357 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5358 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5359 assert(BaseRT && "Don't know how to handle dependent bases"); 5360 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5361 if (!(BaseRecTy->*hasTrivial)()) { 5362 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5363 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5364 DiagnoseNontrivial(BaseRT, member); 5365 return; 5366 } 5367 } 5368 5369 // Check for nontrivial members (and recurse). 5370 typedef RecordDecl::field_iterator field_iter; 5371 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5372 ++fi) { 5373 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5374 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5375 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5376 5377 if (!(EltRD->*hasTrivial)()) { 5378 SourceLocation FLoc = (*fi)->getLocation(); 5379 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5380 DiagnoseNontrivial(EltRT, member); 5381 return; 5382 } 5383 } 5384 } 5385 5386 assert(0 && "found no explanation for non-trivial member"); 5387} 5388 5389/// TranslateIvarVisibility - Translate visibility from a token ID to an 5390/// AST enum value. 5391static ObjCIvarDecl::AccessControl 5392TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5393 switch (ivarVisibility) { 5394 default: assert(0 && "Unknown visitibility kind"); 5395 case tok::objc_private: return ObjCIvarDecl::Private; 5396 case tok::objc_public: return ObjCIvarDecl::Public; 5397 case tok::objc_protected: return ObjCIvarDecl::Protected; 5398 case tok::objc_package: return ObjCIvarDecl::Package; 5399 } 5400} 5401 5402/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5403/// in order to create an IvarDecl object for it. 5404Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5405 SourceLocation DeclStart, 5406 DeclPtrTy IntfDecl, 5407 Declarator &D, ExprTy *BitfieldWidth, 5408 tok::ObjCKeywordKind Visibility) { 5409 5410 IdentifierInfo *II = D.getIdentifier(); 5411 Expr *BitWidth = (Expr*)BitfieldWidth; 5412 SourceLocation Loc = DeclStart; 5413 if (II) Loc = D.getIdentifierLoc(); 5414 5415 // FIXME: Unnamed fields can be handled in various different ways, for 5416 // example, unnamed unions inject all members into the struct namespace! 5417 5418 TypeSourceInfo *TInfo = 0; 5419 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5420 5421 if (BitWidth) { 5422 // 6.7.2.1p3, 6.7.2.1p4 5423 if (VerifyBitField(Loc, II, T, BitWidth)) { 5424 D.setInvalidType(); 5425 DeleteExpr(BitWidth); 5426 BitWidth = 0; 5427 } 5428 } else { 5429 // Not a bitfield. 5430 5431 // validate II. 5432 5433 } 5434 5435 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5436 // than a variably modified type. 5437 if (T->isVariablyModifiedType()) { 5438 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5439 D.setInvalidType(); 5440 } 5441 5442 // Get the visibility (access control) for this ivar. 5443 ObjCIvarDecl::AccessControl ac = 5444 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5445 : ObjCIvarDecl::None; 5446 // Must set ivar's DeclContext to its enclosing interface. 5447 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5448 DeclContext *EnclosingContext; 5449 if (ObjCImplementationDecl *IMPDecl = 5450 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5451 // Case of ivar declared in an implementation. Context is that of its class. 5452 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5453 assert(IDecl && "No class- ActOnIvar"); 5454 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5455 } else 5456 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5457 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5458 5459 // Construct the decl. 5460 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5461 EnclosingContext, Loc, II, T, 5462 TInfo, ac, (Expr *)BitfieldWidth); 5463 5464 if (II) { 5465 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5466 ForRedeclaration); 5467 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5468 && !isa<TagDecl>(PrevDecl)) { 5469 Diag(Loc, diag::err_duplicate_member) << II; 5470 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5471 NewID->setInvalidDecl(); 5472 } 5473 } 5474 5475 // Process attributes attached to the ivar. 5476 ProcessDeclAttributes(S, NewID, D); 5477 5478 if (D.isInvalidType()) 5479 NewID->setInvalidDecl(); 5480 5481 if (II) { 5482 // FIXME: When interfaces are DeclContexts, we'll need to add 5483 // these to the interface. 5484 S->AddDecl(DeclPtrTy::make(NewID)); 5485 IdResolver.AddDecl(NewID); 5486 } 5487 5488 return DeclPtrTy::make(NewID); 5489} 5490 5491void Sema::ActOnFields(Scope* S, 5492 SourceLocation RecLoc, DeclPtrTy RecDecl, 5493 DeclPtrTy *Fields, unsigned NumFields, 5494 SourceLocation LBrac, SourceLocation RBrac, 5495 AttributeList *Attr) { 5496 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5497 assert(EnclosingDecl && "missing record or interface decl"); 5498 5499 // If the decl this is being inserted into is invalid, then it may be a 5500 // redeclaration or some other bogus case. Don't try to add fields to it. 5501 if (EnclosingDecl->isInvalidDecl()) { 5502 // FIXME: Deallocate fields? 5503 return; 5504 } 5505 5506 5507 // Verify that all the fields are okay. 5508 unsigned NumNamedMembers = 0; 5509 llvm::SmallVector<FieldDecl*, 32> RecFields; 5510 5511 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5512 for (unsigned i = 0; i != NumFields; ++i) { 5513 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5514 5515 // Get the type for the field. 5516 Type *FDTy = FD->getType().getTypePtr(); 5517 5518 if (!FD->isAnonymousStructOrUnion()) { 5519 // Remember all fields written by the user. 5520 RecFields.push_back(FD); 5521 } 5522 5523 // If the field is already invalid for some reason, don't emit more 5524 // diagnostics about it. 5525 if (FD->isInvalidDecl()) { 5526 EnclosingDecl->setInvalidDecl(); 5527 continue; 5528 } 5529 5530 // C99 6.7.2.1p2: 5531 // A structure or union shall not contain a member with 5532 // incomplete or function type (hence, a structure shall not 5533 // contain an instance of itself, but may contain a pointer to 5534 // an instance of itself), except that the last member of a 5535 // structure with more than one named member may have incomplete 5536 // array type; such a structure (and any union containing, 5537 // possibly recursively, a member that is such a structure) 5538 // shall not be a member of a structure or an element of an 5539 // array. 5540 if (FDTy->isFunctionType()) { 5541 // Field declared as a function. 5542 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5543 << FD->getDeclName(); 5544 FD->setInvalidDecl(); 5545 EnclosingDecl->setInvalidDecl(); 5546 continue; 5547 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5548 Record && Record->isStruct()) { 5549 // Flexible array member. 5550 if (NumNamedMembers < 1) { 5551 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5552 << FD->getDeclName(); 5553 FD->setInvalidDecl(); 5554 EnclosingDecl->setInvalidDecl(); 5555 continue; 5556 } 5557 // Okay, we have a legal flexible array member at the end of the struct. 5558 if (Record) 5559 Record->setHasFlexibleArrayMember(true); 5560 } else if (!FDTy->isDependentType() && 5561 RequireCompleteType(FD->getLocation(), FD->getType(), 5562 diag::err_field_incomplete)) { 5563 // Incomplete type 5564 FD->setInvalidDecl(); 5565 EnclosingDecl->setInvalidDecl(); 5566 continue; 5567 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5568 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5569 // If this is a member of a union, then entire union becomes "flexible". 5570 if (Record && Record->isUnion()) { 5571 Record->setHasFlexibleArrayMember(true); 5572 } else { 5573 // If this is a struct/class and this is not the last element, reject 5574 // it. Note that GCC supports variable sized arrays in the middle of 5575 // structures. 5576 if (i != NumFields-1) 5577 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5578 << FD->getDeclName() << FD->getType(); 5579 else { 5580 // We support flexible arrays at the end of structs in 5581 // other structs as an extension. 5582 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5583 << FD->getDeclName(); 5584 if (Record) 5585 Record->setHasFlexibleArrayMember(true); 5586 } 5587 } 5588 } 5589 if (Record && FDTTy->getDecl()->hasObjectMember()) 5590 Record->setHasObjectMember(true); 5591 } else if (FDTy->isObjCInterfaceType()) { 5592 /// A field cannot be an Objective-c object 5593 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5594 FD->setInvalidDecl(); 5595 EnclosingDecl->setInvalidDecl(); 5596 continue; 5597 } else if (getLangOptions().ObjC1 && 5598 getLangOptions().getGCMode() != LangOptions::NonGC && 5599 Record && 5600 (FD->getType()->isObjCObjectPointerType() || 5601 FD->getType().isObjCGCStrong())) 5602 Record->setHasObjectMember(true); 5603 // Keep track of the number of named members. 5604 if (FD->getIdentifier()) 5605 ++NumNamedMembers; 5606 } 5607 5608 // Okay, we successfully defined 'Record'. 5609 if (Record) { 5610 Record->completeDefinition(Context); 5611 } else { 5612 ObjCIvarDecl **ClsFields = 5613 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5614 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5615 ID->setIVarList(ClsFields, RecFields.size(), Context); 5616 ID->setLocEnd(RBrac); 5617 // Add ivar's to class's DeclContext. 5618 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5619 ClsFields[i]->setLexicalDeclContext(ID); 5620 ID->addDecl(ClsFields[i]); 5621 } 5622 // Must enforce the rule that ivars in the base classes may not be 5623 // duplicates. 5624 if (ID->getSuperClass()) { 5625 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5626 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5627 ObjCIvarDecl* Ivar = (*IVI); 5628 5629 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5630 ObjCIvarDecl* prevIvar = 5631 ID->getSuperClass()->lookupInstanceVariable(II); 5632 if (prevIvar) { 5633 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5634 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5635 } 5636 } 5637 } 5638 } 5639 } else if (ObjCImplementationDecl *IMPDecl = 5640 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5641 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5642 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5643 // Ivar declared in @implementation never belongs to the implementation. 5644 // Only it is in implementation's lexical context. 5645 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5646 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5647 } 5648 } 5649 5650 if (Attr) 5651 ProcessDeclAttributeList(S, Record, Attr); 5652} 5653 5654EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5655 EnumConstantDecl *LastEnumConst, 5656 SourceLocation IdLoc, 5657 IdentifierInfo *Id, 5658 ExprArg val) { 5659 Expr *Val = (Expr *)val.get(); 5660 5661 llvm::APSInt EnumVal(32); 5662 QualType EltTy; 5663 if (Val) { 5664 if (Enum->isDependentType()) 5665 EltTy = Context.DependentTy; 5666 else { 5667 // Make sure to promote the operand type to int. 5668 UsualUnaryConversions(Val); 5669 if (Val != val.get()) { 5670 val.release(); 5671 val = Val; 5672 } 5673 5674 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5675 SourceLocation ExpLoc; 5676 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 5677 Val = 0; 5678 } else { 5679 EltTy = Val->getType(); 5680 } 5681 } 5682 } 5683 5684 if (!Val) { 5685 if (Enum->isDependentType()) 5686 EltTy = Context.DependentTy; 5687 else if (LastEnumConst) { 5688 // Assign the last value + 1. 5689 EnumVal = LastEnumConst->getInitVal(); 5690 ++EnumVal; 5691 5692 // Check for overflow on increment. 5693 if (EnumVal < LastEnumConst->getInitVal()) 5694 Diag(IdLoc, diag::warn_enum_value_overflow); 5695 5696 EltTy = LastEnumConst->getType(); 5697 } else { 5698 // First value, set to zero. 5699 EltTy = Context.IntTy; 5700 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5701 EnumVal.setIsSigned(true); 5702 } 5703 } 5704 5705 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5706 5707 val.release(); 5708 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5709 Val, EnumVal); 5710} 5711 5712 5713Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5714 DeclPtrTy lastEnumConst, 5715 SourceLocation IdLoc, 5716 IdentifierInfo *Id, 5717 SourceLocation EqualLoc, ExprTy *val) { 5718 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5719 EnumConstantDecl *LastEnumConst = 5720 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5721 Expr *Val = static_cast<Expr*>(val); 5722 5723 // The scope passed in may not be a decl scope. Zip up the scope tree until 5724 // we find one that is. 5725 S = getNonFieldDeclScope(S); 5726 5727 // Verify that there isn't already something declared with this name in this 5728 // scope. 5729 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5730 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5731 // Maybe we will complain about the shadowed template parameter. 5732 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5733 // Just pretend that we didn't see the previous declaration. 5734 PrevDecl = 0; 5735 } 5736 5737 if (PrevDecl) { 5738 // When in C++, we may get a TagDecl with the same name; in this case the 5739 // enum constant will 'hide' the tag. 5740 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5741 "Received TagDecl when not in C++!"); 5742 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5743 if (isa<EnumConstantDecl>(PrevDecl)) 5744 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5745 else 5746 Diag(IdLoc, diag::err_redefinition) << Id; 5747 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5748 if (Val) Val->Destroy(Context); 5749 return DeclPtrTy(); 5750 } 5751 } 5752 5753 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5754 IdLoc, Id, Owned(Val)); 5755 5756 // Register this decl in the current scope stack. 5757 if (New) 5758 PushOnScopeChains(New, S); 5759 5760 return DeclPtrTy::make(New); 5761} 5762 5763void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5764 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5765 DeclPtrTy *Elements, unsigned NumElements, 5766 Scope *S, AttributeList *Attr) { 5767 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5768 QualType EnumType = Context.getTypeDeclType(Enum); 5769 5770 if (Attr) 5771 ProcessDeclAttributeList(S, Enum, Attr); 5772 5773 if (Enum->isDependentType()) { 5774 for (unsigned i = 0; i != NumElements; ++i) { 5775 EnumConstantDecl *ECD = 5776 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5777 if (!ECD) continue; 5778 5779 ECD->setType(EnumType); 5780 } 5781 5782 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 5783 return; 5784 } 5785 5786 // TODO: If the result value doesn't fit in an int, it must be a long or long 5787 // long value. ISO C does not support this, but GCC does as an extension, 5788 // emit a warning. 5789 unsigned IntWidth = Context.Target.getIntWidth(); 5790 unsigned CharWidth = Context.Target.getCharWidth(); 5791 unsigned ShortWidth = Context.Target.getShortWidth(); 5792 5793 // Verify that all the values are okay, compute the size of the values, and 5794 // reverse the list. 5795 unsigned NumNegativeBits = 0; 5796 unsigned NumPositiveBits = 0; 5797 5798 // Keep track of whether all elements have type int. 5799 bool AllElementsInt = true; 5800 5801 for (unsigned i = 0; i != NumElements; ++i) { 5802 EnumConstantDecl *ECD = 5803 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5804 if (!ECD) continue; // Already issued a diagnostic. 5805 5806 // If the enum value doesn't fit in an int, emit an extension warning. 5807 const llvm::APSInt &InitVal = ECD->getInitVal(); 5808 assert(InitVal.getBitWidth() >= IntWidth && 5809 "Should have promoted value to int"); 5810 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 5811 llvm::APSInt V(InitVal); 5812 V.trunc(IntWidth); 5813 V.extend(InitVal.getBitWidth()); 5814 if (V != InitVal) 5815 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5816 << InitVal.toString(10); 5817 } 5818 5819 // Keep track of the size of positive and negative values. 5820 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5821 NumPositiveBits = std::max(NumPositiveBits, 5822 (unsigned)InitVal.getActiveBits()); 5823 else 5824 NumNegativeBits = std::max(NumNegativeBits, 5825 (unsigned)InitVal.getMinSignedBits()); 5826 5827 // Keep track of whether every enum element has type int (very commmon). 5828 if (AllElementsInt) 5829 AllElementsInt = ECD->getType() == Context.IntTy; 5830 } 5831 5832 // Figure out the type that should be used for this enum. 5833 // FIXME: Support -fshort-enums. 5834 QualType BestType; 5835 unsigned BestWidth; 5836 5837 // C++0x N3000 [conv.prom]p3: 5838 // An rvalue of an unscoped enumeration type whose underlying 5839 // type is not fixed can be converted to an rvalue of the first 5840 // of the following types that can represent all the values of 5841 // the enumeration: int, unsigned int, long int, unsigned long 5842 // int, long long int, or unsigned long long int. 5843 // C99 6.4.4.3p2: 5844 // An identifier declared as an enumeration constant has type int. 5845 // The C99 rule is modified by a gcc extension 5846 QualType BestPromotionType; 5847 5848 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5849 5850 if (NumNegativeBits) { 5851 // If there is a negative value, figure out the smallest integer type (of 5852 // int/long/longlong) that fits. 5853 // If it's packed, check also if it fits a char or a short. 5854 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5855 BestType = Context.SignedCharTy; 5856 BestWidth = CharWidth; 5857 } else if (Packed && NumNegativeBits <= ShortWidth && 5858 NumPositiveBits < ShortWidth) { 5859 BestType = Context.ShortTy; 5860 BestWidth = ShortWidth; 5861 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5862 BestType = Context.IntTy; 5863 BestWidth = IntWidth; 5864 } else { 5865 BestWidth = Context.Target.getLongWidth(); 5866 5867 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5868 BestType = Context.LongTy; 5869 } else { 5870 BestWidth = Context.Target.getLongLongWidth(); 5871 5872 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5873 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5874 BestType = Context.LongLongTy; 5875 } 5876 } 5877 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5878 } else { 5879 // If there is no negative value, figure out which of uint, ulong, ulonglong 5880 // fits. 5881 // If it's packed, check also if it fits a char or a short. 5882 if (Packed && NumPositiveBits <= CharWidth) { 5883 BestType = Context.UnsignedCharTy; 5884 BestPromotionType = Context.IntTy; 5885 BestWidth = CharWidth; 5886 } else if (Packed && NumPositiveBits <= ShortWidth) { 5887 BestType = Context.UnsignedShortTy; 5888 BestPromotionType = Context.IntTy; 5889 BestWidth = ShortWidth; 5890 } else if (NumPositiveBits <= IntWidth) { 5891 BestType = Context.UnsignedIntTy; 5892 BestWidth = IntWidth; 5893 BestPromotionType = (NumPositiveBits == BestWidth 5894 ? Context.UnsignedIntTy : Context.IntTy); 5895 } else if (NumPositiveBits <= 5896 (BestWidth = Context.Target.getLongWidth())) { 5897 BestType = Context.UnsignedLongTy; 5898 BestPromotionType = (NumPositiveBits == BestWidth 5899 ? Context.UnsignedLongTy : Context.LongTy); 5900 } else { 5901 BestWidth = Context.Target.getLongLongWidth(); 5902 assert(NumPositiveBits <= BestWidth && 5903 "How could an initializer get larger than ULL?"); 5904 BestType = Context.UnsignedLongLongTy; 5905 BestPromotionType = (NumPositiveBits == BestWidth 5906 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5907 } 5908 } 5909 5910 // If we're in C and the promotion type is larger than an int, just 5911 // use the underlying type, which is generally the unsigned integer 5912 // type of the same rank as the promotion type. This is how the gcc 5913 // extension works. 5914 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5915 BestPromotionType = BestType; 5916 5917 // Loop over all of the enumerator constants, changing their types to match 5918 // the type of the enum if needed. 5919 for (unsigned i = 0; i != NumElements; ++i) { 5920 EnumConstantDecl *ECD = 5921 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5922 if (!ECD) continue; // Already issued a diagnostic. 5923 5924 // Standard C says the enumerators have int type, but we allow, as an 5925 // extension, the enumerators to be larger than int size. If each 5926 // enumerator value fits in an int, type it as an int, otherwise type it the 5927 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5928 // that X has type 'int', not 'unsigned'. 5929 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 5930 continue; 5931 5932 // Determine whether the value fits into an int. 5933 llvm::APSInt InitVal = ECD->getInitVal(); 5934 bool FitsInInt; 5935 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5936 FitsInInt = InitVal.getActiveBits() < IntWidth; 5937 else 5938 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5939 5940 // If it fits into an integer type, force it. Otherwise force it to match 5941 // the enum decl type. 5942 QualType NewTy; 5943 unsigned NewWidth; 5944 bool NewSign; 5945 if (FitsInInt && !getLangOptions().CPlusPlus) { 5946 NewTy = Context.IntTy; 5947 NewWidth = IntWidth; 5948 NewSign = true; 5949 } else if (ECD->getType() == BestType) { 5950 // Already the right type! 5951 if (getLangOptions().CPlusPlus) 5952 // C++ [dcl.enum]p4: Following the closing brace of an 5953 // enum-specifier, each enumerator has the type of its 5954 // enumeration. 5955 ECD->setType(EnumType); 5956 continue; 5957 } else { 5958 NewTy = BestType; 5959 NewWidth = BestWidth; 5960 NewSign = BestType->isSignedIntegerType(); 5961 } 5962 5963 // Adjust the APSInt value. 5964 InitVal.extOrTrunc(NewWidth); 5965 InitVal.setIsSigned(NewSign); 5966 ECD->setInitVal(InitVal); 5967 5968 // Adjust the Expr initializer and type. 5969 if (ECD->getInitExpr()) 5970 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5971 CastExpr::CK_IntegralCast, 5972 ECD->getInitExpr(), 5973 /*isLvalue=*/false)); 5974 if (getLangOptions().CPlusPlus) 5975 // C++ [dcl.enum]p4: Following the closing brace of an 5976 // enum-specifier, each enumerator has the type of its 5977 // enumeration. 5978 ECD->setType(EnumType); 5979 else 5980 ECD->setType(NewTy); 5981 } 5982 5983 Enum->completeDefinition(Context, BestType, BestPromotionType); 5984} 5985 5986Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5987 ExprArg expr) { 5988 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5989 5990 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5991 Loc, AsmString); 5992 CurContext->addDecl(New); 5993 return DeclPtrTy::make(New); 5994} 5995 5996void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5997 SourceLocation PragmaLoc, 5998 SourceLocation NameLoc) { 5999 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6000 6001 if (PrevDecl) { 6002 PrevDecl->addAttr(::new (Context) WeakAttr()); 6003 } else { 6004 (void)WeakUndeclaredIdentifiers.insert( 6005 std::pair<IdentifierInfo*,WeakInfo> 6006 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6007 } 6008} 6009 6010void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6011 IdentifierInfo* AliasName, 6012 SourceLocation PragmaLoc, 6013 SourceLocation NameLoc, 6014 SourceLocation AliasNameLoc) { 6015 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6016 WeakInfo W = WeakInfo(Name, NameLoc); 6017 6018 if (PrevDecl) { 6019 if (!PrevDecl->hasAttr<AliasAttr>()) 6020 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6021 DeclApplyPragmaWeak(TUScope, ND, W); 6022 } else { 6023 (void)WeakUndeclaredIdentifiers.insert( 6024 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6025 } 6026} 6027