SemaDecl.cpp revision 2aaad63ec5d012e6de40f72e114c60df9c205a24
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 if (isa<AsmStmt>(S)) { 1257 HasFakeEdge = true; 1258 HasLiveReturn = true; 1259 continue; 1260 } 1261 bool NoReturnEdge = false; 1262 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1263 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1264 if (CEE->getType().getNoReturnAttr()) { 1265 NoReturnEdge = true; 1266 HasFakeEdge = true; 1267 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1268 ValueDecl *VD = DRE->getDecl(); 1269 if (VD->hasAttr<NoReturnAttr>()) { 1270 NoReturnEdge = true; 1271 HasFakeEdge = true; 1272 } 1273 } 1274 } 1275 // FIXME: Add noreturn message sends. 1276 if (NoReturnEdge == false) 1277 HasPlainEdge = true; 1278 } 1279 if (!HasPlainEdge) { 1280 if (HasLiveReturn) 1281 return NeverFallThrough; 1282 return NeverFallThroughOrReturn; 1283 } 1284 if (HasFakeEdge || HasLiveReturn) 1285 return MaybeFallThrough; 1286 // This says AlwaysFallThrough for calls to functions that are not marked 1287 // noreturn, that don't return. If people would like this warning to be more 1288 // accurate, such functions should be marked as noreturn. 1289 return AlwaysFallThrough; 1290} 1291 1292/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1293/// function that should return a value. Check that we don't fall off the end 1294/// of a noreturn function. We assume that functions and blocks not marked 1295/// noreturn will return. 1296void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1297 // FIXME: Would be nice if we had a better way to control cascading errors, 1298 // but for now, avoid them. The problem is that when Parse sees: 1299 // int foo() { return a; } 1300 // The return is eaten and the Sema code sees just: 1301 // int foo() { } 1302 // which this code would then warn about. 1303 if (getDiagnostics().hasErrorOccurred()) 1304 return; 1305 1306 bool ReturnsVoid = false; 1307 bool HasNoReturn = false; 1308 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1309 // If the result type of the function is a dependent type, we don't know 1310 // whether it will be void or not, so don't 1311 if (FD->getResultType()->isDependentType()) 1312 return; 1313 if (FD->getResultType()->isVoidType()) 1314 ReturnsVoid = true; 1315 if (FD->hasAttr<NoReturnAttr>()) 1316 HasNoReturn = true; 1317 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1318 if (MD->getResultType()->isVoidType()) 1319 ReturnsVoid = true; 1320 if (MD->hasAttr<NoReturnAttr>()) 1321 HasNoReturn = true; 1322 } 1323 1324 // Short circuit for compilation speed. 1325 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1326 == Diagnostic::Ignored || ReturnsVoid) 1327 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1328 == Diagnostic::Ignored || !HasNoReturn) 1329 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1330 == Diagnostic::Ignored || !ReturnsVoid)) 1331 return; 1332 // FIXME: Function try block 1333 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1334 switch (CheckFallThrough(Body)) { 1335 case MaybeFallThrough: 1336 if (HasNoReturn) 1337 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1338 else if (!ReturnsVoid) 1339 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1340 break; 1341 case AlwaysFallThrough: 1342 if (HasNoReturn) 1343 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1344 else if (!ReturnsVoid) 1345 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1346 break; 1347 case NeverFallThroughOrReturn: 1348 if (ReturnsVoid && !HasNoReturn) 1349 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1350 break; 1351 case NeverFallThrough: 1352 break; 1353 } 1354 } 1355} 1356 1357/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1358/// that should return a value. Check that we don't fall off the end of a 1359/// noreturn block. We assume that functions and blocks not marked noreturn 1360/// will return. 1361void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1362 // FIXME: Would be nice if we had a better way to control cascading errors, 1363 // but for now, avoid them. The problem is that when Parse sees: 1364 // int foo() { return a; } 1365 // The return is eaten and the Sema code sees just: 1366 // int foo() { } 1367 // which this code would then warn about. 1368 if (getDiagnostics().hasErrorOccurred()) 1369 return; 1370 bool ReturnsVoid = false; 1371 bool HasNoReturn = false; 1372 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1373 if (FT->getResultType()->isVoidType()) 1374 ReturnsVoid = true; 1375 if (FT->getNoReturnAttr()) 1376 HasNoReturn = true; 1377 } 1378 1379 // Short circuit for compilation speed. 1380 if (ReturnsVoid 1381 && !HasNoReturn 1382 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1383 == Diagnostic::Ignored || !ReturnsVoid)) 1384 return; 1385 // FIXME: Funtion try block 1386 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1387 switch (CheckFallThrough(Body)) { 1388 case MaybeFallThrough: 1389 if (HasNoReturn) 1390 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1391 else if (!ReturnsVoid) 1392 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1393 break; 1394 case AlwaysFallThrough: 1395 if (HasNoReturn) 1396 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1397 else if (!ReturnsVoid) 1398 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1399 break; 1400 case NeverFallThroughOrReturn: 1401 if (ReturnsVoid) 1402 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1403 break; 1404 case NeverFallThrough: 1405 break; 1406 } 1407 } 1408} 1409 1410/// CheckParmsForFunctionDef - Check that the parameters of the given 1411/// function are appropriate for the definition of a function. This 1412/// takes care of any checks that cannot be performed on the 1413/// declaration itself, e.g., that the types of each of the function 1414/// parameters are complete. 1415bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1416 bool HasInvalidParm = false; 1417 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1418 ParmVarDecl *Param = FD->getParamDecl(p); 1419 1420 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1421 // function declarator that is part of a function definition of 1422 // that function shall not have incomplete type. 1423 // 1424 // This is also C++ [dcl.fct]p6. 1425 if (!Param->isInvalidDecl() && 1426 RequireCompleteType(Param->getLocation(), Param->getType(), 1427 diag::err_typecheck_decl_incomplete_type)) { 1428 Param->setInvalidDecl(); 1429 HasInvalidParm = true; 1430 } 1431 1432 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1433 // declaration of each parameter shall include an identifier. 1434 if (Param->getIdentifier() == 0 && 1435 !Param->isImplicit() && 1436 !getLangOptions().CPlusPlus) 1437 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1438 } 1439 1440 return HasInvalidParm; 1441} 1442 1443/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1444/// no declarator (e.g. "struct foo;") is parsed. 1445Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1446 // FIXME: Error on auto/register at file scope 1447 // FIXME: Error on inline/virtual/explicit 1448 // FIXME: Error on invalid restrict 1449 // FIXME: Warn on useless __thread 1450 // FIXME: Warn on useless const/volatile 1451 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1452 // FIXME: Warn on useless attributes 1453 Decl *TagD = 0; 1454 TagDecl *Tag = 0; 1455 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1456 DS.getTypeSpecType() == DeclSpec::TST_struct || 1457 DS.getTypeSpecType() == DeclSpec::TST_union || 1458 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1459 TagD = static_cast<Decl *>(DS.getTypeRep()); 1460 1461 if (!TagD) // We probably had an error 1462 return DeclPtrTy(); 1463 1464 // Note that the above type specs guarantee that the 1465 // type rep is a Decl, whereas in many of the others 1466 // it's a Type. 1467 Tag = dyn_cast<TagDecl>(TagD); 1468 } 1469 1470 if (DS.isFriendSpecified()) { 1471 // If we're dealing with a class template decl, assume that the 1472 // template routines are handling it. 1473 if (TagD && isa<ClassTemplateDecl>(TagD)) 1474 return DeclPtrTy(); 1475 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1476 } 1477 1478 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1479 // If there are attributes in the DeclSpec, apply them to the record. 1480 if (const AttributeList *AL = DS.getAttributes()) 1481 ProcessDeclAttributeList(S, Record, AL); 1482 1483 if (!Record->getDeclName() && Record->isDefinition() && 1484 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1485 if (getLangOptions().CPlusPlus || 1486 Record->getDeclContext()->isRecord()) 1487 return BuildAnonymousStructOrUnion(S, DS, Record); 1488 1489 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1490 << DS.getSourceRange(); 1491 } 1492 1493 // Microsoft allows unnamed struct/union fields. Don't complain 1494 // about them. 1495 // FIXME: Should we support Microsoft's extensions in this area? 1496 if (Record->getDeclName() && getLangOptions().Microsoft) 1497 return DeclPtrTy::make(Tag); 1498 } 1499 1500 if (!DS.isMissingDeclaratorOk() && 1501 DS.getTypeSpecType() != DeclSpec::TST_error) { 1502 // Warn about typedefs of enums without names, since this is an 1503 // extension in both Microsoft an GNU. 1504 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1505 Tag && isa<EnumDecl>(Tag)) { 1506 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1507 << DS.getSourceRange(); 1508 return DeclPtrTy::make(Tag); 1509 } 1510 1511 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1512 << DS.getSourceRange(); 1513 return DeclPtrTy(); 1514 } 1515 1516 return DeclPtrTy::make(Tag); 1517} 1518 1519/// We are trying to introduce the given name into the given context; 1520/// check if there's an existing declaration that can't be overloaded. 1521/// 1522/// \return true if this is a forbidden redeclaration 1523bool Sema::CheckRedeclaration(DeclContext *DC, 1524 DeclarationName Name, 1525 SourceLocation NameLoc, 1526 unsigned diagnostic) { 1527 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName, 1528 ForRedeclaration); 1529 LookupQualifiedName(R, DC); 1530 1531 if (R.empty()) return false; 1532 1533 if (R.getResultKind() == LookupResult::Found && 1534 isa<TagDecl>(R.getFoundDecl())) 1535 return false; 1536 1537 // Pick a representative declaration. 1538 NamedDecl *PrevDecl = (*R.begin())->getUnderlyingDecl(); 1539 1540 Diag(NameLoc, diagnostic) << Name; 1541 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1542 1543 return true; 1544} 1545 1546/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1547/// anonymous struct or union AnonRecord into the owning context Owner 1548/// and scope S. This routine will be invoked just after we realize 1549/// that an unnamed union or struct is actually an anonymous union or 1550/// struct, e.g., 1551/// 1552/// @code 1553/// union { 1554/// int i; 1555/// float f; 1556/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1557/// // f into the surrounding scope.x 1558/// @endcode 1559/// 1560/// This routine is recursive, injecting the names of nested anonymous 1561/// structs/unions into the owning context and scope as well. 1562bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1563 RecordDecl *AnonRecord) { 1564 unsigned diagKind 1565 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1566 : diag::err_anonymous_struct_member_redecl; 1567 1568 bool Invalid = false; 1569 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1570 FEnd = AnonRecord->field_end(); 1571 F != FEnd; ++F) { 1572 if ((*F)->getDeclName()) { 1573 if (CheckRedeclaration(Owner, (*F)->getDeclName(), 1574 (*F)->getLocation(), diagKind)) { 1575 // C++ [class.union]p2: 1576 // The names of the members of an anonymous union shall be 1577 // distinct from the names of any other entity in the 1578 // scope in which the anonymous union is declared. 1579 Invalid = true; 1580 } else { 1581 // C++ [class.union]p2: 1582 // For the purpose of name lookup, after the anonymous union 1583 // definition, the members of the anonymous union are 1584 // considered to have been defined in the scope in which the 1585 // anonymous union is declared. 1586 Owner->makeDeclVisibleInContext(*F); 1587 S->AddDecl(DeclPtrTy::make(*F)); 1588 IdResolver.AddDecl(*F); 1589 } 1590 } else if (const RecordType *InnerRecordType 1591 = (*F)->getType()->getAs<RecordType>()) { 1592 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1593 if (InnerRecord->isAnonymousStructOrUnion()) 1594 Invalid = Invalid || 1595 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1596 } 1597 } 1598 1599 return Invalid; 1600} 1601 1602/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1603/// anonymous structure or union. Anonymous unions are a C++ feature 1604/// (C++ [class.union]) and a GNU C extension; anonymous structures 1605/// are a GNU C and GNU C++ extension. 1606Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1607 RecordDecl *Record) { 1608 DeclContext *Owner = Record->getDeclContext(); 1609 1610 // Diagnose whether this anonymous struct/union is an extension. 1611 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1612 Diag(Record->getLocation(), diag::ext_anonymous_union); 1613 else if (!Record->isUnion()) 1614 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1615 1616 // C and C++ require different kinds of checks for anonymous 1617 // structs/unions. 1618 bool Invalid = false; 1619 if (getLangOptions().CPlusPlus) { 1620 const char* PrevSpec = 0; 1621 unsigned DiagID; 1622 // C++ [class.union]p3: 1623 // Anonymous unions declared in a named namespace or in the 1624 // global namespace shall be declared static. 1625 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1626 (isa<TranslationUnitDecl>(Owner) || 1627 (isa<NamespaceDecl>(Owner) && 1628 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1629 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1630 Invalid = true; 1631 1632 // Recover by adding 'static'. 1633 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1634 PrevSpec, DiagID); 1635 } 1636 // C++ [class.union]p3: 1637 // A storage class is not allowed in a declaration of an 1638 // anonymous union in a class scope. 1639 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1640 isa<RecordDecl>(Owner)) { 1641 Diag(DS.getStorageClassSpecLoc(), 1642 diag::err_anonymous_union_with_storage_spec); 1643 Invalid = true; 1644 1645 // Recover by removing the storage specifier. 1646 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1647 PrevSpec, DiagID); 1648 } 1649 1650 // C++ [class.union]p2: 1651 // The member-specification of an anonymous union shall only 1652 // define non-static data members. [Note: nested types and 1653 // functions cannot be declared within an anonymous union. ] 1654 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1655 MemEnd = Record->decls_end(); 1656 Mem != MemEnd; ++Mem) { 1657 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1658 // C++ [class.union]p3: 1659 // An anonymous union shall not have private or protected 1660 // members (clause 11). 1661 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1662 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1663 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1664 Invalid = true; 1665 } 1666 } else if ((*Mem)->isImplicit()) { 1667 // Any implicit members are fine. 1668 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1669 // This is a type that showed up in an 1670 // elaborated-type-specifier inside the anonymous struct or 1671 // union, but which actually declares a type outside of the 1672 // anonymous struct or union. It's okay. 1673 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1674 if (!MemRecord->isAnonymousStructOrUnion() && 1675 MemRecord->getDeclName()) { 1676 // This is a nested type declaration. 1677 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1678 << (int)Record->isUnion(); 1679 Invalid = true; 1680 } 1681 } else { 1682 // We have something that isn't a non-static data 1683 // member. Complain about it. 1684 unsigned DK = diag::err_anonymous_record_bad_member; 1685 if (isa<TypeDecl>(*Mem)) 1686 DK = diag::err_anonymous_record_with_type; 1687 else if (isa<FunctionDecl>(*Mem)) 1688 DK = diag::err_anonymous_record_with_function; 1689 else if (isa<VarDecl>(*Mem)) 1690 DK = diag::err_anonymous_record_with_static; 1691 Diag((*Mem)->getLocation(), DK) 1692 << (int)Record->isUnion(); 1693 Invalid = true; 1694 } 1695 } 1696 } 1697 1698 if (!Record->isUnion() && !Owner->isRecord()) { 1699 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1700 << (int)getLangOptions().CPlusPlus; 1701 Invalid = true; 1702 } 1703 1704 // Mock up a declarator. 1705 Declarator Dc(DS, Declarator::TypeNameContext); 1706 TypeSourceInfo *TInfo = 0; 1707 GetTypeForDeclarator(Dc, S, &TInfo); 1708 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1709 1710 // Create a declaration for this anonymous struct/union. 1711 NamedDecl *Anon = 0; 1712 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1713 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1714 /*IdentifierInfo=*/0, 1715 Context.getTypeDeclType(Record), 1716 TInfo, 1717 /*BitWidth=*/0, /*Mutable=*/false); 1718 Anon->setAccess(AS_public); 1719 if (getLangOptions().CPlusPlus) 1720 FieldCollector->Add(cast<FieldDecl>(Anon)); 1721 } else { 1722 VarDecl::StorageClass SC; 1723 switch (DS.getStorageClassSpec()) { 1724 default: assert(0 && "Unknown storage class!"); 1725 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1726 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1727 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1728 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1729 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1730 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1731 case DeclSpec::SCS_mutable: 1732 // mutable can only appear on non-static class members, so it's always 1733 // an error here 1734 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1735 Invalid = true; 1736 SC = VarDecl::None; 1737 break; 1738 } 1739 1740 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1741 /*IdentifierInfo=*/0, 1742 Context.getTypeDeclType(Record), 1743 TInfo, 1744 SC); 1745 } 1746 Anon->setImplicit(); 1747 1748 // Add the anonymous struct/union object to the current 1749 // context. We'll be referencing this object when we refer to one of 1750 // its members. 1751 Owner->addDecl(Anon); 1752 1753 // Inject the members of the anonymous struct/union into the owning 1754 // context and into the identifier resolver chain for name lookup 1755 // purposes. 1756 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1757 Invalid = true; 1758 1759 // Mark this as an anonymous struct/union type. Note that we do not 1760 // do this until after we have already checked and injected the 1761 // members of this anonymous struct/union type, because otherwise 1762 // the members could be injected twice: once by DeclContext when it 1763 // builds its lookup table, and once by 1764 // InjectAnonymousStructOrUnionMembers. 1765 Record->setAnonymousStructOrUnion(true); 1766 1767 if (Invalid) 1768 Anon->setInvalidDecl(); 1769 1770 return DeclPtrTy::make(Anon); 1771} 1772 1773 1774/// GetNameForDeclarator - Determine the full declaration name for the 1775/// given Declarator. 1776DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1777 return GetNameFromUnqualifiedId(D.getName()); 1778} 1779 1780/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1781DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1782 switch (Name.getKind()) { 1783 case UnqualifiedId::IK_Identifier: 1784 return DeclarationName(Name.Identifier); 1785 1786 case UnqualifiedId::IK_OperatorFunctionId: 1787 return Context.DeclarationNames.getCXXOperatorName( 1788 Name.OperatorFunctionId.Operator); 1789 1790 case UnqualifiedId::IK_LiteralOperatorId: 1791 return Context.DeclarationNames.getCXXLiteralOperatorName( 1792 Name.Identifier); 1793 1794 case UnqualifiedId::IK_ConversionFunctionId: { 1795 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1796 if (Ty.isNull()) 1797 return DeclarationName(); 1798 1799 return Context.DeclarationNames.getCXXConversionFunctionName( 1800 Context.getCanonicalType(Ty)); 1801 } 1802 1803 case UnqualifiedId::IK_ConstructorName: { 1804 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1805 if (Ty.isNull()) 1806 return DeclarationName(); 1807 1808 return Context.DeclarationNames.getCXXConstructorName( 1809 Context.getCanonicalType(Ty)); 1810 } 1811 1812 case UnqualifiedId::IK_DestructorName: { 1813 QualType Ty = GetTypeFromParser(Name.DestructorName); 1814 if (Ty.isNull()) 1815 return DeclarationName(); 1816 1817 return Context.DeclarationNames.getCXXDestructorName( 1818 Context.getCanonicalType(Ty)); 1819 } 1820 1821 case UnqualifiedId::IK_TemplateId: { 1822 TemplateName TName 1823 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1824 return Context.getNameForTemplate(TName); 1825 } 1826 } 1827 1828 assert(false && "Unknown name kind"); 1829 return DeclarationName(); 1830} 1831 1832/// isNearlyMatchingFunction - Determine whether the C++ functions 1833/// Declaration and Definition are "nearly" matching. This heuristic 1834/// is used to improve diagnostics in the case where an out-of-line 1835/// function definition doesn't match any declaration within 1836/// the class or namespace. 1837static bool isNearlyMatchingFunction(ASTContext &Context, 1838 FunctionDecl *Declaration, 1839 FunctionDecl *Definition) { 1840 if (Declaration->param_size() != Definition->param_size()) 1841 return false; 1842 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1843 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1844 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1845 1846 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1847 DefParamTy.getNonReferenceType())) 1848 return false; 1849 } 1850 1851 return true; 1852} 1853 1854Sema::DeclPtrTy 1855Sema::HandleDeclarator(Scope *S, Declarator &D, 1856 MultiTemplateParamsArg TemplateParamLists, 1857 bool IsFunctionDefinition) { 1858 DeclarationName Name = GetNameForDeclarator(D); 1859 1860 // All of these full declarators require an identifier. If it doesn't have 1861 // one, the ParsedFreeStandingDeclSpec action should be used. 1862 if (!Name) { 1863 if (!D.isInvalidType()) // Reject this if we think it is valid. 1864 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1865 diag::err_declarator_need_ident) 1866 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1867 return DeclPtrTy(); 1868 } 1869 1870 // The scope passed in may not be a decl scope. Zip up the scope tree until 1871 // we find one that is. 1872 while ((S->getFlags() & Scope::DeclScope) == 0 || 1873 (S->getFlags() & Scope::TemplateParamScope) != 0) 1874 S = S->getParent(); 1875 1876 // If this is an out-of-line definition of a member of a class template 1877 // or class template partial specialization, we may need to rebuild the 1878 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1879 // for more information. 1880 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1881 // handle expressions properly. 1882 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1883 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1884 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1885 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1886 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1887 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1888 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1889 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1890 // FIXME: Preserve type source info. 1891 QualType T = GetTypeFromParser(DS.getTypeRep()); 1892 EnterDeclaratorContext(S, DC); 1893 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1894 ExitDeclaratorContext(S); 1895 if (T.isNull()) 1896 return DeclPtrTy(); 1897 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1898 } 1899 } 1900 1901 DeclContext *DC; 1902 NamedDecl *New; 1903 1904 TypeSourceInfo *TInfo = 0; 1905 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1906 1907 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1908 ForRedeclaration); 1909 1910 // See if this is a redefinition of a variable in the same scope. 1911 if (D.getCXXScopeSpec().isInvalid()) { 1912 DC = CurContext; 1913 D.setInvalidType(); 1914 } else if (!D.getCXXScopeSpec().isSet()) { 1915 bool IsLinkageLookup = false; 1916 1917 // If the declaration we're planning to build will be a function 1918 // or object with linkage, then look for another declaration with 1919 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1920 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1921 /* Do nothing*/; 1922 else if (R->isFunctionType()) { 1923 if (CurContext->isFunctionOrMethod() || 1924 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1925 IsLinkageLookup = true; 1926 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1927 IsLinkageLookup = true; 1928 else if (CurContext->getLookupContext()->isTranslationUnit() && 1929 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1930 IsLinkageLookup = true; 1931 1932 if (IsLinkageLookup) 1933 Previous.clear(LookupRedeclarationWithLinkage); 1934 1935 DC = CurContext; 1936 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1937 } else { // Something like "int foo::x;" 1938 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1939 1940 if (!DC) { 1941 // If we could not compute the declaration context, it's because the 1942 // declaration context is dependent but does not refer to a class, 1943 // class template, or class template partial specialization. Complain 1944 // and return early, to avoid the coming semantic disaster. 1945 Diag(D.getIdentifierLoc(), 1946 diag::err_template_qualified_declarator_no_match) 1947 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1948 << D.getCXXScopeSpec().getRange(); 1949 return DeclPtrTy(); 1950 } 1951 1952 if (!DC->isDependentContext() && 1953 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1954 return DeclPtrTy(); 1955 1956 LookupQualifiedName(Previous, DC); 1957 1958 // Don't consider using declarations as previous declarations for 1959 // out-of-line members. 1960 RemoveUsingDecls(Previous); 1961 1962 // C++ 7.3.1.2p2: 1963 // Members (including explicit specializations of templates) of a named 1964 // namespace can also be defined outside that namespace by explicit 1965 // qualification of the name being defined, provided that the entity being 1966 // defined was already declared in the namespace and the definition appears 1967 // after the point of declaration in a namespace that encloses the 1968 // declarations namespace. 1969 // 1970 // Note that we only check the context at this point. We don't yet 1971 // have enough information to make sure that PrevDecl is actually 1972 // the declaration we want to match. For example, given: 1973 // 1974 // class X { 1975 // void f(); 1976 // void f(float); 1977 // }; 1978 // 1979 // void X::f(int) { } // ill-formed 1980 // 1981 // In this case, PrevDecl will point to the overload set 1982 // containing the two f's declared in X, but neither of them 1983 // matches. 1984 1985 // First check whether we named the global scope. 1986 if (isa<TranslationUnitDecl>(DC)) { 1987 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1988 << Name << D.getCXXScopeSpec().getRange(); 1989 } else { 1990 DeclContext *Cur = CurContext; 1991 while (isa<LinkageSpecDecl>(Cur)) 1992 Cur = Cur->getParent(); 1993 if (!Cur->Encloses(DC)) { 1994 // The qualifying scope doesn't enclose the original declaration. 1995 // Emit diagnostic based on current scope. 1996 SourceLocation L = D.getIdentifierLoc(); 1997 SourceRange R = D.getCXXScopeSpec().getRange(); 1998 if (isa<FunctionDecl>(Cur)) 1999 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 2000 else 2001 Diag(L, diag::err_invalid_declarator_scope) 2002 << Name << cast<NamedDecl>(DC) << R; 2003 D.setInvalidType(); 2004 } 2005 } 2006 } 2007 2008 if (Previous.isSingleResult() && 2009 Previous.getFoundDecl()->isTemplateParameter()) { 2010 // Maybe we will complain about the shadowed template parameter. 2011 if (!D.isInvalidType()) 2012 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2013 Previous.getFoundDecl())) 2014 D.setInvalidType(); 2015 2016 // Just pretend that we didn't see the previous declaration. 2017 Previous.clear(); 2018 } 2019 2020 // In C++, the previous declaration we find might be a tag type 2021 // (class or enum). In this case, the new declaration will hide the 2022 // tag type. Note that this does does not apply if we're declaring a 2023 // typedef (C++ [dcl.typedef]p4). 2024 if (Previous.isSingleTagDecl() && 2025 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2026 Previous.clear(); 2027 2028 bool Redeclaration = false; 2029 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2030 if (TemplateParamLists.size()) { 2031 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2032 return DeclPtrTy(); 2033 } 2034 2035 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2036 } else if (R->isFunctionType()) { 2037 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2038 move(TemplateParamLists), 2039 IsFunctionDefinition, Redeclaration); 2040 } else { 2041 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2042 move(TemplateParamLists), 2043 Redeclaration); 2044 } 2045 2046 if (New == 0) 2047 return DeclPtrTy(); 2048 2049 // If this has an identifier and is not an invalid redeclaration or 2050 // function template specialization, add it to the scope stack. 2051 if (Name && !(Redeclaration && New->isInvalidDecl())) 2052 PushOnScopeChains(New, S); 2053 2054 return DeclPtrTy::make(New); 2055} 2056 2057/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2058/// types into constant array types in certain situations which would otherwise 2059/// be errors (for GCC compatibility). 2060static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2061 ASTContext &Context, 2062 bool &SizeIsNegative) { 2063 // This method tries to turn a variable array into a constant 2064 // array even when the size isn't an ICE. This is necessary 2065 // for compatibility with code that depends on gcc's buggy 2066 // constant expression folding, like struct {char x[(int)(char*)2];} 2067 SizeIsNegative = false; 2068 2069 QualifierCollector Qs; 2070 const Type *Ty = Qs.strip(T); 2071 2072 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2073 QualType Pointee = PTy->getPointeeType(); 2074 QualType FixedType = 2075 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2076 if (FixedType.isNull()) return FixedType; 2077 FixedType = Context.getPointerType(FixedType); 2078 return Qs.apply(FixedType); 2079 } 2080 2081 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2082 if (!VLATy) 2083 return QualType(); 2084 // FIXME: We should probably handle this case 2085 if (VLATy->getElementType()->isVariablyModifiedType()) 2086 return QualType(); 2087 2088 Expr::EvalResult EvalResult; 2089 if (!VLATy->getSizeExpr() || 2090 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2091 !EvalResult.Val.isInt()) 2092 return QualType(); 2093 2094 llvm::APSInt &Res = EvalResult.Val.getInt(); 2095 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2096 // TODO: preserve the size expression in declarator info 2097 return Context.getConstantArrayType(VLATy->getElementType(), 2098 Res, ArrayType::Normal, 0); 2099 } 2100 2101 SizeIsNegative = true; 2102 return QualType(); 2103} 2104 2105/// \brief Register the given locally-scoped external C declaration so 2106/// that it can be found later for redeclarations 2107void 2108Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2109 const LookupResult &Previous, 2110 Scope *S) { 2111 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2112 "Decl is not a locally-scoped decl!"); 2113 // Note that we have a locally-scoped external with this name. 2114 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2115 2116 if (!Previous.isSingleResult()) 2117 return; 2118 2119 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2120 2121 // If there was a previous declaration of this variable, it may be 2122 // in our identifier chain. Update the identifier chain with the new 2123 // declaration. 2124 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2125 // The previous declaration was found on the identifer resolver 2126 // chain, so remove it from its scope. 2127 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2128 S = S->getParent(); 2129 2130 if (S) 2131 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2132 } 2133} 2134 2135/// \brief Diagnose function specifiers on a declaration of an identifier that 2136/// does not identify a function. 2137void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2138 // FIXME: We should probably indicate the identifier in question to avoid 2139 // confusion for constructs like "inline int a(), b;" 2140 if (D.getDeclSpec().isInlineSpecified()) 2141 Diag(D.getDeclSpec().getInlineSpecLoc(), 2142 diag::err_inline_non_function); 2143 2144 if (D.getDeclSpec().isVirtualSpecified()) 2145 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2146 diag::err_virtual_non_function); 2147 2148 if (D.getDeclSpec().isExplicitSpecified()) 2149 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2150 diag::err_explicit_non_function); 2151} 2152 2153NamedDecl* 2154Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2155 QualType R, TypeSourceInfo *TInfo, 2156 LookupResult &Previous, bool &Redeclaration) { 2157 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2158 if (D.getCXXScopeSpec().isSet()) { 2159 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2160 << D.getCXXScopeSpec().getRange(); 2161 D.setInvalidType(); 2162 // Pretend we didn't see the scope specifier. 2163 DC = 0; 2164 } 2165 2166 if (getLangOptions().CPlusPlus) { 2167 // Check that there are no default arguments (C++ only). 2168 CheckExtraCXXDefaultArguments(D); 2169 } 2170 2171 DiagnoseFunctionSpecifiers(D); 2172 2173 if (D.getDeclSpec().isThreadSpecified()) 2174 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2175 2176 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2177 if (!NewTD) return 0; 2178 2179 // Handle attributes prior to checking for duplicates in MergeVarDecl 2180 ProcessDeclAttributes(S, NewTD, D); 2181 2182 // Merge the decl with the existing one if appropriate. If the decl is 2183 // in an outer scope, it isn't the same thing. 2184 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2185 if (!Previous.empty()) { 2186 Redeclaration = true; 2187 MergeTypeDefDecl(NewTD, Previous); 2188 } 2189 2190 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2191 // then it shall have block scope. 2192 QualType T = NewTD->getUnderlyingType(); 2193 if (T->isVariablyModifiedType()) { 2194 CurFunctionNeedsScopeChecking = true; 2195 2196 if (S->getFnParent() == 0) { 2197 bool SizeIsNegative; 2198 QualType FixedTy = 2199 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2200 if (!FixedTy.isNull()) { 2201 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2202 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2203 } else { 2204 if (SizeIsNegative) 2205 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2206 else if (T->isVariableArrayType()) 2207 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2208 else 2209 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2210 NewTD->setInvalidDecl(); 2211 } 2212 } 2213 } 2214 2215 // If this is the C FILE type, notify the AST context. 2216 if (IdentifierInfo *II = NewTD->getIdentifier()) 2217 if (!NewTD->isInvalidDecl() && 2218 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2219 if (II->isStr("FILE")) 2220 Context.setFILEDecl(NewTD); 2221 else if (II->isStr("jmp_buf")) 2222 Context.setjmp_bufDecl(NewTD); 2223 else if (II->isStr("sigjmp_buf")) 2224 Context.setsigjmp_bufDecl(NewTD); 2225 } 2226 2227 return NewTD; 2228} 2229 2230/// \brief Determines whether the given declaration is an out-of-scope 2231/// previous declaration. 2232/// 2233/// This routine should be invoked when name lookup has found a 2234/// previous declaration (PrevDecl) that is not in the scope where a 2235/// new declaration by the same name is being introduced. If the new 2236/// declaration occurs in a local scope, previous declarations with 2237/// linkage may still be considered previous declarations (C99 2238/// 6.2.2p4-5, C++ [basic.link]p6). 2239/// 2240/// \param PrevDecl the previous declaration found by name 2241/// lookup 2242/// 2243/// \param DC the context in which the new declaration is being 2244/// declared. 2245/// 2246/// \returns true if PrevDecl is an out-of-scope previous declaration 2247/// for a new delcaration with the same name. 2248static bool 2249isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2250 ASTContext &Context) { 2251 if (!PrevDecl) 2252 return 0; 2253 2254 if (!PrevDecl->hasLinkage()) 2255 return false; 2256 2257 if (Context.getLangOptions().CPlusPlus) { 2258 // C++ [basic.link]p6: 2259 // If there is a visible declaration of an entity with linkage 2260 // having the same name and type, ignoring entities declared 2261 // outside the innermost enclosing namespace scope, the block 2262 // scope declaration declares that same entity and receives the 2263 // linkage of the previous declaration. 2264 DeclContext *OuterContext = DC->getLookupContext(); 2265 if (!OuterContext->isFunctionOrMethod()) 2266 // This rule only applies to block-scope declarations. 2267 return false; 2268 else { 2269 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2270 if (PrevOuterContext->isRecord()) 2271 // We found a member function: ignore it. 2272 return false; 2273 else { 2274 // Find the innermost enclosing namespace for the new and 2275 // previous declarations. 2276 while (!OuterContext->isFileContext()) 2277 OuterContext = OuterContext->getParent(); 2278 while (!PrevOuterContext->isFileContext()) 2279 PrevOuterContext = PrevOuterContext->getParent(); 2280 2281 // The previous declaration is in a different namespace, so it 2282 // isn't the same function. 2283 if (OuterContext->getPrimaryContext() != 2284 PrevOuterContext->getPrimaryContext()) 2285 return false; 2286 } 2287 } 2288 } 2289 2290 return true; 2291} 2292 2293NamedDecl* 2294Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2295 QualType R, TypeSourceInfo *TInfo, 2296 LookupResult &Previous, 2297 MultiTemplateParamsArg TemplateParamLists, 2298 bool &Redeclaration) { 2299 DeclarationName Name = GetNameForDeclarator(D); 2300 2301 // Check that there are no default arguments (C++ only). 2302 if (getLangOptions().CPlusPlus) 2303 CheckExtraCXXDefaultArguments(D); 2304 2305 VarDecl *NewVD; 2306 VarDecl::StorageClass SC; 2307 switch (D.getDeclSpec().getStorageClassSpec()) { 2308 default: assert(0 && "Unknown storage class!"); 2309 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2310 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2311 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2312 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2313 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2314 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2315 case DeclSpec::SCS_mutable: 2316 // mutable can only appear on non-static class members, so it's always 2317 // an error here 2318 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2319 D.setInvalidType(); 2320 SC = VarDecl::None; 2321 break; 2322 } 2323 2324 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2325 if (!II) { 2326 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2327 << Name.getAsString(); 2328 return 0; 2329 } 2330 2331 DiagnoseFunctionSpecifiers(D); 2332 2333 if (!DC->isRecord() && S->getFnParent() == 0) { 2334 // C99 6.9p2: The storage-class specifiers auto and register shall not 2335 // appear in the declaration specifiers in an external declaration. 2336 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2337 2338 // If this is a register variable with an asm label specified, then this 2339 // is a GNU extension. 2340 if (SC == VarDecl::Register && D.getAsmLabel()) 2341 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2342 else 2343 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2344 D.setInvalidType(); 2345 } 2346 } 2347 if (DC->isRecord() && !CurContext->isRecord()) { 2348 // This is an out-of-line definition of a static data member. 2349 if (SC == VarDecl::Static) { 2350 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2351 diag::err_static_out_of_line) 2352 << CodeModificationHint::CreateRemoval( 2353 D.getDeclSpec().getStorageClassSpecLoc()); 2354 } else if (SC == VarDecl::None) 2355 SC = VarDecl::Static; 2356 } 2357 if (SC == VarDecl::Static) { 2358 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2359 if (RD->isLocalClass()) 2360 Diag(D.getIdentifierLoc(), 2361 diag::err_static_data_member_not_allowed_in_local_class) 2362 << Name << RD->getDeclName(); 2363 } 2364 } 2365 2366 // Match up the template parameter lists with the scope specifier, then 2367 // determine whether we have a template or a template specialization. 2368 bool isExplicitSpecialization = false; 2369 if (TemplateParameterList *TemplateParams 2370 = MatchTemplateParametersToScopeSpecifier( 2371 D.getDeclSpec().getSourceRange().getBegin(), 2372 D.getCXXScopeSpec(), 2373 (TemplateParameterList**)TemplateParamLists.get(), 2374 TemplateParamLists.size(), 2375 isExplicitSpecialization)) { 2376 if (TemplateParams->size() > 0) { 2377 // There is no such thing as a variable template. 2378 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2379 << II 2380 << SourceRange(TemplateParams->getTemplateLoc(), 2381 TemplateParams->getRAngleLoc()); 2382 return 0; 2383 } else { 2384 // There is an extraneous 'template<>' for this variable. Complain 2385 // about it, but allow the declaration of the variable. 2386 Diag(TemplateParams->getTemplateLoc(), 2387 diag::err_template_variable_noparams) 2388 << II 2389 << SourceRange(TemplateParams->getTemplateLoc(), 2390 TemplateParams->getRAngleLoc()); 2391 2392 isExplicitSpecialization = true; 2393 } 2394 } 2395 2396 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2397 II, R, TInfo, SC); 2398 2399 if (D.isInvalidType()) 2400 NewVD->setInvalidDecl(); 2401 2402 if (D.getDeclSpec().isThreadSpecified()) { 2403 if (NewVD->hasLocalStorage()) 2404 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2405 else if (!Context.Target.isTLSSupported()) 2406 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2407 else 2408 NewVD->setThreadSpecified(true); 2409 } 2410 2411 // Set the lexical context. If the declarator has a C++ scope specifier, the 2412 // lexical context will be different from the semantic context. 2413 NewVD->setLexicalDeclContext(CurContext); 2414 2415 // Handle attributes prior to checking for duplicates in MergeVarDecl 2416 ProcessDeclAttributes(S, NewVD, D); 2417 2418 // Handle GNU asm-label extension (encoded as an attribute). 2419 if (Expr *E = (Expr*) D.getAsmLabel()) { 2420 // The parser guarantees this is a string. 2421 StringLiteral *SE = cast<StringLiteral>(E); 2422 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2423 } 2424 2425 // Don't consider existing declarations that are in a different 2426 // scope and are out-of-semantic-context declarations (if the new 2427 // declaration has linkage). 2428 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2429 2430 // Merge the decl with the existing one if appropriate. 2431 if (!Previous.empty()) { 2432 if (Previous.isSingleResult() && 2433 isa<FieldDecl>(Previous.getFoundDecl()) && 2434 D.getCXXScopeSpec().isSet()) { 2435 // The user tried to define a non-static data member 2436 // out-of-line (C++ [dcl.meaning]p1). 2437 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2438 << D.getCXXScopeSpec().getRange(); 2439 Previous.clear(); 2440 NewVD->setInvalidDecl(); 2441 } 2442 } else if (D.getCXXScopeSpec().isSet()) { 2443 // No previous declaration in the qualifying scope. 2444 Diag(D.getIdentifierLoc(), diag::err_no_member) 2445 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2446 << D.getCXXScopeSpec().getRange(); 2447 NewVD->setInvalidDecl(); 2448 } 2449 2450 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2451 2452 // This is an explicit specialization of a static data member. Check it. 2453 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2454 CheckMemberSpecialization(NewVD, Previous)) 2455 NewVD->setInvalidDecl(); 2456 2457 // attributes declared post-definition are currently ignored 2458 if (Previous.isSingleResult()) { 2459 const VarDecl *Def = 0; 2460 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2461 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2462 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2463 Diag(Def->getLocation(), diag::note_previous_definition); 2464 } 2465 } 2466 2467 // If this is a locally-scoped extern C variable, update the map of 2468 // such variables. 2469 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2470 !NewVD->isInvalidDecl()) 2471 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2472 2473 return NewVD; 2474} 2475 2476/// \brief Perform semantic checking on a newly-created variable 2477/// declaration. 2478/// 2479/// This routine performs all of the type-checking required for a 2480/// variable declaration once it has been built. It is used both to 2481/// check variables after they have been parsed and their declarators 2482/// have been translated into a declaration, and to check variables 2483/// that have been instantiated from a template. 2484/// 2485/// Sets NewVD->isInvalidDecl() if an error was encountered. 2486void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2487 LookupResult &Previous, 2488 bool &Redeclaration) { 2489 // If the decl is already known invalid, don't check it. 2490 if (NewVD->isInvalidDecl()) 2491 return; 2492 2493 QualType T = NewVD->getType(); 2494 2495 if (T->isObjCInterfaceType()) { 2496 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2497 return NewVD->setInvalidDecl(); 2498 } 2499 2500 // Emit an error if an address space was applied to decl with local storage. 2501 // This includes arrays of objects with address space qualifiers, but not 2502 // automatic variables that point to other address spaces. 2503 // ISO/IEC TR 18037 S5.1.2 2504 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2505 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2506 return NewVD->setInvalidDecl(); 2507 } 2508 2509 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2510 && !NewVD->hasAttr<BlocksAttr>()) 2511 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2512 2513 bool isVM = T->isVariablyModifiedType(); 2514 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2515 NewVD->hasAttr<BlocksAttr>()) 2516 CurFunctionNeedsScopeChecking = true; 2517 2518 if ((isVM && NewVD->hasLinkage()) || 2519 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2520 bool SizeIsNegative; 2521 QualType FixedTy = 2522 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2523 2524 if (FixedTy.isNull() && T->isVariableArrayType()) { 2525 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2526 // FIXME: This won't give the correct result for 2527 // int a[10][n]; 2528 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2529 2530 if (NewVD->isFileVarDecl()) 2531 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2532 << SizeRange; 2533 else if (NewVD->getStorageClass() == VarDecl::Static) 2534 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2535 << SizeRange; 2536 else 2537 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2538 << SizeRange; 2539 return NewVD->setInvalidDecl(); 2540 } 2541 2542 if (FixedTy.isNull()) { 2543 if (NewVD->isFileVarDecl()) 2544 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2545 else 2546 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2547 return NewVD->setInvalidDecl(); 2548 } 2549 2550 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2551 NewVD->setType(FixedTy); 2552 } 2553 2554 if (Previous.empty() && NewVD->isExternC()) { 2555 // Since we did not find anything by this name and we're declaring 2556 // an extern "C" variable, look for a non-visible extern "C" 2557 // declaration with the same name. 2558 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2559 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2560 if (Pos != LocallyScopedExternalDecls.end()) 2561 Previous.addDecl(Pos->second); 2562 } 2563 2564 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2565 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2566 << T; 2567 return NewVD->setInvalidDecl(); 2568 } 2569 2570 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2571 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2572 return NewVD->setInvalidDecl(); 2573 } 2574 2575 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2576 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2577 return NewVD->setInvalidDecl(); 2578 } 2579 2580 if (!Previous.empty()) { 2581 Redeclaration = true; 2582 MergeVarDecl(NewVD, Previous); 2583 } 2584} 2585 2586/// \brief Data used with FindOverriddenMethod 2587struct FindOverriddenMethodData { 2588 Sema *S; 2589 CXXMethodDecl *Method; 2590}; 2591 2592/// \brief Member lookup function that determines whether a given C++ 2593/// method overrides a method in a base class, to be used with 2594/// CXXRecordDecl::lookupInBases(). 2595static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2596 CXXBasePath &Path, 2597 void *UserData) { 2598 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2599 2600 FindOverriddenMethodData *Data 2601 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2602 2603 DeclarationName Name = Data->Method->getDeclName(); 2604 2605 // FIXME: Do we care about other names here too? 2606 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2607 // We really want to find the base class constructor here. 2608 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2609 CanQualType CT = Data->S->Context.getCanonicalType(T); 2610 2611 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2612 } 2613 2614 for (Path.Decls = BaseRecord->lookup(Name); 2615 Path.Decls.first != Path.Decls.second; 2616 ++Path.Decls.first) { 2617 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2618 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2619 return true; 2620 } 2621 } 2622 2623 return false; 2624} 2625 2626/// AddOverriddenMethods - See if a method overrides any in the base classes, 2627/// and if so, check that it's a valid override and remember it. 2628void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2629 // Look for virtual methods in base classes that this method might override. 2630 CXXBasePaths Paths; 2631 FindOverriddenMethodData Data; 2632 Data.Method = MD; 2633 Data.S = this; 2634 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2635 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2636 E = Paths.found_decls_end(); I != E; ++I) { 2637 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2638 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2639 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2640 !CheckOverridingFunctionAttributes(MD, OldMD)) 2641 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2642 } 2643 } 2644 } 2645} 2646 2647NamedDecl* 2648Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2649 QualType R, TypeSourceInfo *TInfo, 2650 LookupResult &Previous, 2651 MultiTemplateParamsArg TemplateParamLists, 2652 bool IsFunctionDefinition, bool &Redeclaration) { 2653 assert(R.getTypePtr()->isFunctionType()); 2654 2655 DeclarationName Name = GetNameForDeclarator(D); 2656 FunctionDecl::StorageClass SC = FunctionDecl::None; 2657 switch (D.getDeclSpec().getStorageClassSpec()) { 2658 default: assert(0 && "Unknown storage class!"); 2659 case DeclSpec::SCS_auto: 2660 case DeclSpec::SCS_register: 2661 case DeclSpec::SCS_mutable: 2662 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2663 diag::err_typecheck_sclass_func); 2664 D.setInvalidType(); 2665 break; 2666 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2667 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2668 case DeclSpec::SCS_static: { 2669 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2670 // C99 6.7.1p5: 2671 // The declaration of an identifier for a function that has 2672 // block scope shall have no explicit storage-class specifier 2673 // other than extern 2674 // See also (C++ [dcl.stc]p4). 2675 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2676 diag::err_static_block_func); 2677 SC = FunctionDecl::None; 2678 } else 2679 SC = FunctionDecl::Static; 2680 break; 2681 } 2682 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2683 } 2684 2685 if (D.getDeclSpec().isThreadSpecified()) 2686 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2687 2688 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2689 bool isInline = D.getDeclSpec().isInlineSpecified(); 2690 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2691 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2692 2693 // Check that the return type is not an abstract class type. 2694 // For record types, this is done by the AbstractClassUsageDiagnoser once 2695 // the class has been completely parsed. 2696 if (!DC->isRecord() && 2697 RequireNonAbstractType(D.getIdentifierLoc(), 2698 R->getAs<FunctionType>()->getResultType(), 2699 diag::err_abstract_type_in_decl, 2700 AbstractReturnType)) 2701 D.setInvalidType(); 2702 2703 // Do not allow returning a objc interface by-value. 2704 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2705 Diag(D.getIdentifierLoc(), 2706 diag::err_object_cannot_be_passed_returned_by_value) << 0 2707 << R->getAs<FunctionType>()->getResultType(); 2708 D.setInvalidType(); 2709 } 2710 2711 bool isVirtualOkay = false; 2712 FunctionDecl *NewFD; 2713 2714 if (isFriend) { 2715 // C++ [class.friend]p5 2716 // A function can be defined in a friend declaration of a 2717 // class . . . . Such a function is implicitly inline. 2718 isInline |= IsFunctionDefinition; 2719 } 2720 2721 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2722 // This is a C++ constructor declaration. 2723 assert(DC->isRecord() && 2724 "Constructors can only be declared in a member context"); 2725 2726 R = CheckConstructorDeclarator(D, R, SC); 2727 2728 // Create the new declaration 2729 NewFD = CXXConstructorDecl::Create(Context, 2730 cast<CXXRecordDecl>(DC), 2731 D.getIdentifierLoc(), Name, R, TInfo, 2732 isExplicit, isInline, 2733 /*isImplicitlyDeclared=*/false); 2734 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2735 // This is a C++ destructor declaration. 2736 if (DC->isRecord()) { 2737 R = CheckDestructorDeclarator(D, SC); 2738 2739 NewFD = CXXDestructorDecl::Create(Context, 2740 cast<CXXRecordDecl>(DC), 2741 D.getIdentifierLoc(), Name, R, 2742 isInline, 2743 /*isImplicitlyDeclared=*/false); 2744 2745 isVirtualOkay = true; 2746 } else { 2747 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2748 2749 // Create a FunctionDecl to satisfy the function definition parsing 2750 // code path. 2751 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2752 Name, R, TInfo, SC, isInline, 2753 /*hasPrototype=*/true); 2754 D.setInvalidType(); 2755 } 2756 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2757 if (!DC->isRecord()) { 2758 Diag(D.getIdentifierLoc(), 2759 diag::err_conv_function_not_member); 2760 return 0; 2761 } 2762 2763 CheckConversionDeclarator(D, R, SC); 2764 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2765 D.getIdentifierLoc(), Name, R, TInfo, 2766 isInline, isExplicit); 2767 2768 isVirtualOkay = true; 2769 } else if (DC->isRecord()) { 2770 // If the of the function is the same as the name of the record, then this 2771 // must be an invalid constructor that has a return type. 2772 // (The parser checks for a return type and makes the declarator a 2773 // constructor if it has no return type). 2774 // must have an invalid constructor that has a return type 2775 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2776 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2777 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2778 << SourceRange(D.getIdentifierLoc()); 2779 return 0; 2780 } 2781 2782 bool isStatic = SC == FunctionDecl::Static; 2783 2784 // [class.free]p1: 2785 // Any allocation function for a class T is a static member 2786 // (even if not explicitly declared static). 2787 if (Name.getCXXOverloadedOperator() == OO_New || 2788 Name.getCXXOverloadedOperator() == OO_Array_New) 2789 isStatic = true; 2790 2791 // [class.free]p6 Any deallocation function for a class X is a static member 2792 // (even if not explicitly declared static). 2793 if (Name.getCXXOverloadedOperator() == OO_Delete || 2794 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2795 isStatic = true; 2796 2797 // This is a C++ method declaration. 2798 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2799 D.getIdentifierLoc(), Name, R, TInfo, 2800 isStatic, isInline); 2801 2802 if ((Name.getCXXOverloadedOperator() == OO_New || 2803 Name.getCXXOverloadedOperator() == OO_Array_New) && 2804 getLangOptions().AssumeSaneOperatorNew) 2805 NewFD->addAttr(::new (Context) MallocAttr()); 2806 2807 isVirtualOkay = !isStatic; 2808 } else { 2809 // Determine whether the function was written with a 2810 // prototype. This true when: 2811 // - we're in C++ (where every function has a prototype), 2812 // - there is a prototype in the declarator, or 2813 // - the type R of the function is some kind of typedef or other reference 2814 // to a type name (which eventually refers to a function type). 2815 bool HasPrototype = 2816 getLangOptions().CPlusPlus || 2817 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2818 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2819 2820 NewFD = FunctionDecl::Create(Context, DC, 2821 D.getIdentifierLoc(), 2822 Name, R, TInfo, SC, isInline, HasPrototype); 2823 } 2824 2825 if (D.isInvalidType()) 2826 NewFD->setInvalidDecl(); 2827 2828 // Set the lexical context. If the declarator has a C++ 2829 // scope specifier, or is the object of a friend declaration, the 2830 // lexical context will be different from the semantic context. 2831 NewFD->setLexicalDeclContext(CurContext); 2832 2833 // Match up the template parameter lists with the scope specifier, then 2834 // determine whether we have a template or a template specialization. 2835 FunctionTemplateDecl *FunctionTemplate = 0; 2836 bool isExplicitSpecialization = false; 2837 bool isFunctionTemplateSpecialization = false; 2838 if (TemplateParameterList *TemplateParams 2839 = MatchTemplateParametersToScopeSpecifier( 2840 D.getDeclSpec().getSourceRange().getBegin(), 2841 D.getCXXScopeSpec(), 2842 (TemplateParameterList**)TemplateParamLists.get(), 2843 TemplateParamLists.size(), 2844 isExplicitSpecialization)) { 2845 if (TemplateParams->size() > 0) { 2846 // This is a function template 2847 2848 // Check that we can declare a template here. 2849 if (CheckTemplateDeclScope(S, TemplateParams)) 2850 return 0; 2851 2852 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2853 NewFD->getLocation(), 2854 Name, TemplateParams, 2855 NewFD); 2856 FunctionTemplate->setLexicalDeclContext(CurContext); 2857 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2858 } else { 2859 // This is a function template specialization. 2860 isFunctionTemplateSpecialization = true; 2861 } 2862 2863 // FIXME: Free this memory properly. 2864 TemplateParamLists.release(); 2865 } 2866 2867 // C++ [dcl.fct.spec]p5: 2868 // The virtual specifier shall only be used in declarations of 2869 // nonstatic class member functions that appear within a 2870 // member-specification of a class declaration; see 10.3. 2871 // 2872 if (isVirtual && !NewFD->isInvalidDecl()) { 2873 if (!isVirtualOkay) { 2874 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2875 diag::err_virtual_non_function); 2876 } else if (!CurContext->isRecord()) { 2877 // 'virtual' was specified outside of the class. 2878 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2879 << CodeModificationHint::CreateRemoval( 2880 D.getDeclSpec().getVirtualSpecLoc()); 2881 } else { 2882 // Okay: Add virtual to the method. 2883 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2884 CurClass->setMethodAsVirtual(NewFD); 2885 } 2886 } 2887 2888 // Filter out previous declarations that don't match the scope. 2889 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2890 2891 if (isFriend) { 2892 // DC is the namespace in which the function is being declared. 2893 assert((DC->isFileContext() || !Previous.empty()) && 2894 "previously-undeclared friend function being created " 2895 "in a non-namespace context"); 2896 2897 if (FunctionTemplate) { 2898 FunctionTemplate->setObjectOfFriendDecl( 2899 /* PreviouslyDeclared= */ !Previous.empty()); 2900 FunctionTemplate->setAccess(AS_public); 2901 } 2902 else 2903 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2904 2905 NewFD->setAccess(AS_public); 2906 } 2907 2908 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2909 !CurContext->isRecord()) { 2910 // C++ [class.static]p1: 2911 // A data or function member of a class may be declared static 2912 // in a class definition, in which case it is a static member of 2913 // the class. 2914 2915 // Complain about the 'static' specifier if it's on an out-of-line 2916 // member function definition. 2917 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2918 diag::err_static_out_of_line) 2919 << CodeModificationHint::CreateRemoval( 2920 D.getDeclSpec().getStorageClassSpecLoc()); 2921 } 2922 2923 // Handle GNU asm-label extension (encoded as an attribute). 2924 if (Expr *E = (Expr*) D.getAsmLabel()) { 2925 // The parser guarantees this is a string. 2926 StringLiteral *SE = cast<StringLiteral>(E); 2927 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2928 } 2929 2930 // Copy the parameter declarations from the declarator D to the function 2931 // declaration NewFD, if they are available. First scavenge them into Params. 2932 llvm::SmallVector<ParmVarDecl*, 16> Params; 2933 if (D.getNumTypeObjects() > 0) { 2934 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2935 2936 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2937 // function that takes no arguments, not a function that takes a 2938 // single void argument. 2939 // We let through "const void" here because Sema::GetTypeForDeclarator 2940 // already checks for that case. 2941 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2942 FTI.ArgInfo[0].Param && 2943 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2944 // Empty arg list, don't push any params. 2945 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2946 2947 // In C++, the empty parameter-type-list must be spelled "void"; a 2948 // typedef of void is not permitted. 2949 if (getLangOptions().CPlusPlus && 2950 Param->getType().getUnqualifiedType() != Context.VoidTy) 2951 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2952 // FIXME: Leaks decl? 2953 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2954 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2955 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2956 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2957 Param->setDeclContext(NewFD); 2958 Params.push_back(Param); 2959 } 2960 } 2961 2962 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2963 // When we're declaring a function with a typedef, typeof, etc as in the 2964 // following example, we'll need to synthesize (unnamed) 2965 // parameters for use in the declaration. 2966 // 2967 // @code 2968 // typedef void fn(int); 2969 // fn f; 2970 // @endcode 2971 2972 // Synthesize a parameter for each argument type. 2973 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2974 AE = FT->arg_type_end(); AI != AE; ++AI) { 2975 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2976 SourceLocation(), 0, 2977 *AI, /*TInfo=*/0, 2978 VarDecl::None, 0); 2979 Param->setImplicit(); 2980 Params.push_back(Param); 2981 } 2982 } else { 2983 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2984 "Should not need args for typedef of non-prototype fn"); 2985 } 2986 // Finally, we know we have the right number of parameters, install them. 2987 NewFD->setParams(Context, Params.data(), Params.size()); 2988 2989 // If the declarator is a template-id, translate the parser's template 2990 // argument list into our AST format. 2991 bool HasExplicitTemplateArgs = false; 2992 TemplateArgumentListInfo TemplateArgs; 2993 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2994 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2995 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 2996 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 2997 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2998 TemplateId->getTemplateArgs(), 2999 TemplateId->NumArgs); 3000 translateTemplateArguments(TemplateArgsPtr, 3001 TemplateArgs); 3002 TemplateArgsPtr.release(); 3003 3004 HasExplicitTemplateArgs = true; 3005 3006 if (FunctionTemplate) { 3007 // FIXME: Diagnose function template with explicit template 3008 // arguments. 3009 HasExplicitTemplateArgs = false; 3010 } else if (!isFunctionTemplateSpecialization && 3011 !D.getDeclSpec().isFriendSpecified()) { 3012 // We have encountered something that the user meant to be a 3013 // specialization (because it has explicitly-specified template 3014 // arguments) but that was not introduced with a "template<>" (or had 3015 // too few of them). 3016 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3017 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3018 << CodeModificationHint::CreateInsertion( 3019 D.getDeclSpec().getSourceRange().getBegin(), 3020 "template<> "); 3021 isFunctionTemplateSpecialization = true; 3022 } 3023 } 3024 3025 if (isFunctionTemplateSpecialization) { 3026 if (CheckFunctionTemplateSpecialization(NewFD, 3027 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3028 Previous)) 3029 NewFD->setInvalidDecl(); 3030 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3031 CheckMemberSpecialization(NewFD, Previous)) 3032 NewFD->setInvalidDecl(); 3033 3034 // Perform semantic checking on the function declaration. 3035 bool OverloadableAttrRequired = false; // FIXME: HACK! 3036 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3037 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3038 3039 assert((NewFD->isInvalidDecl() || !Redeclaration || 3040 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3041 "previous declaration set still overloaded"); 3042 3043 // If we have a function template, check the template parameter 3044 // list. This will check and merge default template arguments. 3045 if (FunctionTemplate) { 3046 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3047 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3048 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3049 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3050 : TPC_FunctionTemplate); 3051 } 3052 3053 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3054 // An out-of-line member function declaration must also be a 3055 // definition (C++ [dcl.meaning]p1). 3056 // Note that this is not the case for explicit specializations of 3057 // function templates or member functions of class templates, per 3058 // C++ [temp.expl.spec]p2. 3059 if (!IsFunctionDefinition && !isFriend && 3060 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3061 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3062 << D.getCXXScopeSpec().getRange(); 3063 NewFD->setInvalidDecl(); 3064 } else if (!Redeclaration) { 3065 // The user tried to provide an out-of-line definition for a 3066 // function that is a member of a class or namespace, but there 3067 // was no such member function declared (C++ [class.mfct]p2, 3068 // C++ [namespace.memdef]p2). For example: 3069 // 3070 // class X { 3071 // void f() const; 3072 // }; 3073 // 3074 // void X::f() { } // ill-formed 3075 // 3076 // Complain about this problem, and attempt to suggest close 3077 // matches (e.g., those that differ only in cv-qualifiers and 3078 // whether the parameter types are references). 3079 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3080 << Name << DC << D.getCXXScopeSpec().getRange(); 3081 NewFD->setInvalidDecl(); 3082 3083 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3084 ForRedeclaration); 3085 LookupQualifiedName(Prev, DC); 3086 assert(!Prev.isAmbiguous() && 3087 "Cannot have an ambiguity in previous-declaration lookup"); 3088 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3089 Func != FuncEnd; ++Func) { 3090 if (isa<FunctionDecl>(*Func) && 3091 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3092 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3093 } 3094 } 3095 } 3096 3097 // Handle attributes. We need to have merged decls when handling attributes 3098 // (for example to check for conflicts, etc). 3099 // FIXME: This needs to happen before we merge declarations. Then, 3100 // let attribute merging cope with attribute conflicts. 3101 ProcessDeclAttributes(S, NewFD, D); 3102 3103 // attributes declared post-definition are currently ignored 3104 if (Redeclaration && Previous.isSingleResult()) { 3105 const FunctionDecl *Def; 3106 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3107 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3108 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3109 Diag(Def->getLocation(), diag::note_previous_definition); 3110 } 3111 } 3112 3113 AddKnownFunctionAttributes(NewFD); 3114 3115 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3116 // If a function name is overloadable in C, then every function 3117 // with that name must be marked "overloadable". 3118 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3119 << Redeclaration << NewFD; 3120 if (!Previous.empty()) 3121 Diag(Previous.getRepresentativeDecl()->getLocation(), 3122 diag::note_attribute_overloadable_prev_overload); 3123 NewFD->addAttr(::new (Context) OverloadableAttr()); 3124 } 3125 3126 // If this is a locally-scoped extern C function, update the 3127 // map of such names. 3128 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3129 && !NewFD->isInvalidDecl()) 3130 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3131 3132 // Set this FunctionDecl's range up to the right paren. 3133 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3134 3135 if (FunctionTemplate && NewFD->isInvalidDecl()) 3136 FunctionTemplate->setInvalidDecl(); 3137 3138 if (FunctionTemplate) 3139 return FunctionTemplate; 3140 3141 return NewFD; 3142} 3143 3144/// \brief Perform semantic checking of a new function declaration. 3145/// 3146/// Performs semantic analysis of the new function declaration 3147/// NewFD. This routine performs all semantic checking that does not 3148/// require the actual declarator involved in the declaration, and is 3149/// used both for the declaration of functions as they are parsed 3150/// (called via ActOnDeclarator) and for the declaration of functions 3151/// that have been instantiated via C++ template instantiation (called 3152/// via InstantiateDecl). 3153/// 3154/// \param IsExplicitSpecialiation whether this new function declaration is 3155/// an explicit specialization of the previous declaration. 3156/// 3157/// This sets NewFD->isInvalidDecl() to true if there was an error. 3158void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3159 LookupResult &Previous, 3160 bool IsExplicitSpecialization, 3161 bool &Redeclaration, 3162 bool &OverloadableAttrRequired) { 3163 // If NewFD is already known erroneous, don't do any of this checking. 3164 if (NewFD->isInvalidDecl()) 3165 return; 3166 3167 if (NewFD->getResultType()->isVariablyModifiedType()) { 3168 // Functions returning a variably modified type violate C99 6.7.5.2p2 3169 // because all functions have linkage. 3170 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3171 return NewFD->setInvalidDecl(); 3172 } 3173 3174 if (NewFD->isMain()) 3175 CheckMain(NewFD); 3176 3177 // Check for a previous declaration of this name. 3178 if (Previous.empty() && NewFD->isExternC()) { 3179 // Since we did not find anything by this name and we're declaring 3180 // an extern "C" function, look for a non-visible extern "C" 3181 // declaration with the same name. 3182 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3183 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3184 if (Pos != LocallyScopedExternalDecls.end()) 3185 Previous.addDecl(Pos->second); 3186 } 3187 3188 // Merge or overload the declaration with an existing declaration of 3189 // the same name, if appropriate. 3190 if (!Previous.empty()) { 3191 // Determine whether NewFD is an overload of PrevDecl or 3192 // a declaration that requires merging. If it's an overload, 3193 // there's no more work to do here; we'll just add the new 3194 // function to the scope. 3195 3196 NamedDecl *OldDecl = 0; 3197 if (!AllowOverloadingOfFunction(Previous, Context)) { 3198 Redeclaration = true; 3199 OldDecl = Previous.getFoundDecl(); 3200 } else { 3201 if (!getLangOptions().CPlusPlus) { 3202 OverloadableAttrRequired = true; 3203 3204 // Functions marked "overloadable" must have a prototype (that 3205 // we can't get through declaration merging). 3206 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3207 Diag(NewFD->getLocation(), 3208 diag::err_attribute_overloadable_no_prototype) 3209 << NewFD; 3210 Redeclaration = true; 3211 3212 // Turn this into a variadic function with no parameters. 3213 QualType R = Context.getFunctionType( 3214 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3215 0, 0, true, 0); 3216 NewFD->setType(R); 3217 return NewFD->setInvalidDecl(); 3218 } 3219 } 3220 3221 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3222 case Ovl_Match: 3223 Redeclaration = true; 3224 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3225 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3226 Redeclaration = false; 3227 } 3228 break; 3229 3230 case Ovl_NonFunction: 3231 Redeclaration = true; 3232 break; 3233 3234 case Ovl_Overload: 3235 Redeclaration = false; 3236 break; 3237 } 3238 } 3239 3240 if (Redeclaration) { 3241 // NewFD and OldDecl represent declarations that need to be 3242 // merged. 3243 if (MergeFunctionDecl(NewFD, OldDecl)) 3244 return NewFD->setInvalidDecl(); 3245 3246 Previous.clear(); 3247 Previous.addDecl(OldDecl); 3248 3249 if (FunctionTemplateDecl *OldTemplateDecl 3250 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3251 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3252 FunctionTemplateDecl *NewTemplateDecl 3253 = NewFD->getDescribedFunctionTemplate(); 3254 assert(NewTemplateDecl && "Template/non-template mismatch"); 3255 if (CXXMethodDecl *Method 3256 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3257 Method->setAccess(OldTemplateDecl->getAccess()); 3258 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3259 } 3260 3261 // If this is an explicit specialization of a member that is a function 3262 // template, mark it as a member specialization. 3263 if (IsExplicitSpecialization && 3264 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3265 NewTemplateDecl->setMemberSpecialization(); 3266 assert(OldTemplateDecl->isMemberSpecialization()); 3267 } 3268 } else { 3269 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3270 NewFD->setAccess(OldDecl->getAccess()); 3271 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3272 } 3273 } 3274 } 3275 3276 // Semantic checking for this function declaration (in isolation). 3277 if (getLangOptions().CPlusPlus) { 3278 // C++-specific checks. 3279 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3280 CheckConstructor(Constructor); 3281 } else if (CXXDestructorDecl *Destructor = 3282 dyn_cast<CXXDestructorDecl>(NewFD)) { 3283 CXXRecordDecl *Record = Destructor->getParent(); 3284 QualType ClassType = Context.getTypeDeclType(Record); 3285 3286 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3287 // type is dependent? Both gcc and edg can handle that. 3288 if (!ClassType->isDependentType()) { 3289 DeclarationName Name 3290 = Context.DeclarationNames.getCXXDestructorName( 3291 Context.getCanonicalType(ClassType)); 3292 if (NewFD->getDeclName() != Name) { 3293 Diag(NewFD->getLocation(), diag::err_destructor_name); 3294 return NewFD->setInvalidDecl(); 3295 } 3296 } 3297 3298 Record->setUserDeclaredDestructor(true); 3299 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3300 // user-defined destructor. 3301 Record->setPOD(false); 3302 3303 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3304 // declared destructor. 3305 // FIXME: C++0x: don't do this for "= default" destructors 3306 Record->setHasTrivialDestructor(false); 3307 } else if (CXXConversionDecl *Conversion 3308 = dyn_cast<CXXConversionDecl>(NewFD)) { 3309 ActOnConversionDeclarator(Conversion); 3310 } 3311 3312 // Find any virtual functions that this function overrides. 3313 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3314 if (!Method->isFunctionTemplateSpecialization() && 3315 !Method->getDescribedFunctionTemplate()) 3316 AddOverriddenMethods(Method->getParent(), Method); 3317 } 3318 3319 // Additional checks for the destructor; make sure we do this after we 3320 // figure out whether the destructor is virtual. 3321 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3322 if (!Destructor->getParent()->isDependentType()) 3323 CheckDestructor(Destructor); 3324 3325 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3326 if (NewFD->isOverloadedOperator() && 3327 CheckOverloadedOperatorDeclaration(NewFD)) 3328 return NewFD->setInvalidDecl(); 3329 3330 // In C++, check default arguments now that we have merged decls. Unless 3331 // the lexical context is the class, because in this case this is done 3332 // during delayed parsing anyway. 3333 if (!CurContext->isRecord()) 3334 CheckCXXDefaultArguments(NewFD); 3335 } 3336} 3337 3338void Sema::CheckMain(FunctionDecl* FD) { 3339 // C++ [basic.start.main]p3: A program that declares main to be inline 3340 // or static is ill-formed. 3341 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3342 // shall not appear in a declaration of main. 3343 // static main is not an error under C99, but we should warn about it. 3344 bool isInline = FD->isInlineSpecified(); 3345 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3346 if (isInline || isStatic) { 3347 unsigned diagID = diag::warn_unusual_main_decl; 3348 if (isInline || getLangOptions().CPlusPlus) 3349 diagID = diag::err_unusual_main_decl; 3350 3351 int which = isStatic + (isInline << 1) - 1; 3352 Diag(FD->getLocation(), diagID) << which; 3353 } 3354 3355 QualType T = FD->getType(); 3356 assert(T->isFunctionType() && "function decl is not of function type"); 3357 const FunctionType* FT = T->getAs<FunctionType>(); 3358 3359 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3360 // TODO: add a replacement fixit to turn the return type into 'int'. 3361 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3362 FD->setInvalidDecl(true); 3363 } 3364 3365 // Treat protoless main() as nullary. 3366 if (isa<FunctionNoProtoType>(FT)) return; 3367 3368 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3369 unsigned nparams = FTP->getNumArgs(); 3370 assert(FD->getNumParams() == nparams); 3371 3372 if (nparams > 3) { 3373 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3374 FD->setInvalidDecl(true); 3375 nparams = 3; 3376 } 3377 3378 // FIXME: a lot of the following diagnostics would be improved 3379 // if we had some location information about types. 3380 3381 QualType CharPP = 3382 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3383 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3384 3385 for (unsigned i = 0; i < nparams; ++i) { 3386 QualType AT = FTP->getArgType(i); 3387 3388 bool mismatch = true; 3389 3390 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3391 mismatch = false; 3392 else if (Expected[i] == CharPP) { 3393 // As an extension, the following forms are okay: 3394 // char const ** 3395 // char const * const * 3396 // char * const * 3397 3398 QualifierCollector qs; 3399 const PointerType* PT; 3400 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3401 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3402 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3403 qs.removeConst(); 3404 mismatch = !qs.empty(); 3405 } 3406 } 3407 3408 if (mismatch) { 3409 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3410 // TODO: suggest replacing given type with expected type 3411 FD->setInvalidDecl(true); 3412 } 3413 } 3414 3415 if (nparams == 1 && !FD->isInvalidDecl()) { 3416 Diag(FD->getLocation(), diag::warn_main_one_arg); 3417 } 3418} 3419 3420bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3421 // FIXME: Need strict checking. In C89, we need to check for 3422 // any assignment, increment, decrement, function-calls, or 3423 // commas outside of a sizeof. In C99, it's the same list, 3424 // except that the aforementioned are allowed in unevaluated 3425 // expressions. Everything else falls under the 3426 // "may accept other forms of constant expressions" exception. 3427 // (We never end up here for C++, so the constant expression 3428 // rules there don't matter.) 3429 if (Init->isConstantInitializer(Context)) 3430 return false; 3431 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3432 << Init->getSourceRange(); 3433 return true; 3434} 3435 3436void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3437 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3438} 3439 3440/// AddInitializerToDecl - Adds the initializer Init to the 3441/// declaration dcl. If DirectInit is true, this is C++ direct 3442/// initialization rather than copy initialization. 3443void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3444 Decl *RealDecl = dcl.getAs<Decl>(); 3445 // If there is no declaration, there was an error parsing it. Just ignore 3446 // the initializer. 3447 if (RealDecl == 0) 3448 return; 3449 3450 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3451 // With declarators parsed the way they are, the parser cannot 3452 // distinguish between a normal initializer and a pure-specifier. 3453 // Thus this grotesque test. 3454 IntegerLiteral *IL; 3455 Expr *Init = static_cast<Expr *>(init.get()); 3456 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3457 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3458 CheckPureMethod(Method, Init->getSourceRange()); 3459 else { 3460 Diag(Method->getLocation(), diag::err_member_function_initialization) 3461 << Method->getDeclName() << Init->getSourceRange(); 3462 Method->setInvalidDecl(); 3463 } 3464 return; 3465 } 3466 3467 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3468 if (!VDecl) { 3469 if (getLangOptions().CPlusPlus && 3470 RealDecl->getLexicalDeclContext()->isRecord() && 3471 isa<NamedDecl>(RealDecl)) 3472 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3473 << cast<NamedDecl>(RealDecl)->getDeclName(); 3474 else 3475 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3476 RealDecl->setInvalidDecl(); 3477 return; 3478 } 3479 3480 // A definition must end up with a complete type, which means it must be 3481 // complete with the restriction that an array type might be completed by the 3482 // initializer; note that later code assumes this restriction. 3483 QualType BaseDeclType = VDecl->getType(); 3484 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3485 BaseDeclType = Array->getElementType(); 3486 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3487 diag::err_typecheck_decl_incomplete_type)) { 3488 RealDecl->setInvalidDecl(); 3489 return; 3490 } 3491 3492 // The variable can not have an abstract class type. 3493 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3494 diag::err_abstract_type_in_decl, 3495 AbstractVariableType)) 3496 VDecl->setInvalidDecl(); 3497 3498 const VarDecl *Def = 0; 3499 if (VDecl->getDefinition(Def)) { 3500 Diag(VDecl->getLocation(), diag::err_redefinition) 3501 << VDecl->getDeclName(); 3502 Diag(Def->getLocation(), diag::note_previous_definition); 3503 VDecl->setInvalidDecl(); 3504 return; 3505 } 3506 3507 // Take ownership of the expression, now that we're sure we have somewhere 3508 // to put it. 3509 Expr *Init = init.takeAs<Expr>(); 3510 assert(Init && "missing initializer"); 3511 3512 // Capture the variable that is being initialized and the style of 3513 // initialization. 3514 InitializedEntity Entity = InitializedEntity::InitializeVariable(VDecl); 3515 3516 // FIXME: Poor source location information. 3517 InitializationKind Kind 3518 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3519 Init->getLocStart(), 3520 Init->getLocEnd()) 3521 : InitializationKind::CreateCopy(VDecl->getLocation(), 3522 Init->getLocStart()); 3523 3524 // Get the decls type and save a reference for later, since 3525 // CheckInitializerTypes may change it. 3526 QualType DclT = VDecl->getType(), SavT = DclT; 3527 if (VDecl->isBlockVarDecl()) { 3528 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3529 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3530 VDecl->setInvalidDecl(); 3531 } else if (!VDecl->isInvalidDecl()) { 3532 if (VDecl->getType()->isReferenceType() 3533 || isa<InitListExpr>(Init)) { 3534 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3535 if (InitSeq) { 3536 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3537 MultiExprArg(*this, (void**)&Init, 1), 3538 &DclT); 3539 if (Result.isInvalid()) { 3540 VDecl->setInvalidDecl(); 3541 return; 3542 } 3543 3544 Init = Result.takeAs<Expr>(); 3545 } else { 3546 InitSeq.Diagnose(*this, Entity, Kind, &Init, 1); 3547 VDecl->setInvalidDecl(); 3548 return; 3549 } 3550 } else if (CheckInitializerTypes(Init, DclT, Entity, Kind)) 3551 VDecl->setInvalidDecl(); 3552 3553 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3554 // Don't check invalid declarations to avoid emitting useless diagnostics. 3555 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3556 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3557 CheckForConstantInitializer(Init, DclT); 3558 } 3559 } 3560 } else if (VDecl->isStaticDataMember() && 3561 VDecl->getLexicalDeclContext()->isRecord()) { 3562 // This is an in-class initialization for a static data member, e.g., 3563 // 3564 // struct S { 3565 // static const int value = 17; 3566 // }; 3567 3568 // Attach the initializer 3569 VDecl->setInit(Context, Init); 3570 3571 // C++ [class.mem]p4: 3572 // A member-declarator can contain a constant-initializer only 3573 // if it declares a static member (9.4) of const integral or 3574 // const enumeration type, see 9.4.2. 3575 QualType T = VDecl->getType(); 3576 if (!T->isDependentType() && 3577 (!Context.getCanonicalType(T).isConstQualified() || 3578 !T->isIntegralType())) { 3579 Diag(VDecl->getLocation(), diag::err_member_initialization) 3580 << VDecl->getDeclName() << Init->getSourceRange(); 3581 VDecl->setInvalidDecl(); 3582 } else { 3583 // C++ [class.static.data]p4: 3584 // If a static data member is of const integral or const 3585 // enumeration type, its declaration in the class definition 3586 // can specify a constant-initializer which shall be an 3587 // integral constant expression (5.19). 3588 if (!Init->isTypeDependent() && 3589 !Init->getType()->isIntegralType()) { 3590 // We have a non-dependent, non-integral or enumeration type. 3591 Diag(Init->getSourceRange().getBegin(), 3592 diag::err_in_class_initializer_non_integral_type) 3593 << Init->getType() << Init->getSourceRange(); 3594 VDecl->setInvalidDecl(); 3595 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3596 // Check whether the expression is a constant expression. 3597 llvm::APSInt Value; 3598 SourceLocation Loc; 3599 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3600 Diag(Loc, diag::err_in_class_initializer_non_constant) 3601 << Init->getSourceRange(); 3602 VDecl->setInvalidDecl(); 3603 } else if (!VDecl->getType()->isDependentType()) 3604 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3605 } 3606 } 3607 } else if (VDecl->isFileVarDecl()) { 3608 if (VDecl->getStorageClass() == VarDecl::Extern) 3609 Diag(VDecl->getLocation(), diag::warn_extern_init); 3610 if (!VDecl->isInvalidDecl()) 3611 if (CheckInitializerTypes(Init, DclT, Entity, Kind)) 3612 VDecl->setInvalidDecl(); 3613 3614 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3615 // Don't check invalid declarations to avoid emitting useless diagnostics. 3616 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3617 // C99 6.7.8p4. All file scoped initializers need to be constant. 3618 CheckForConstantInitializer(Init, DclT); 3619 } 3620 } 3621 // If the type changed, it means we had an incomplete type that was 3622 // completed by the initializer. For example: 3623 // int ary[] = { 1, 3, 5 }; 3624 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3625 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3626 VDecl->setType(DclT); 3627 Init->setType(DclT); 3628 } 3629 3630 Init = MaybeCreateCXXExprWithTemporaries(Init); 3631 // Attach the initializer to the decl. 3632 VDecl->setInit(Context, Init); 3633 3634 // If the previous declaration of VDecl was a tentative definition, 3635 // remove it from the set of tentative definitions. 3636 if (VDecl->getPreviousDeclaration() && 3637 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3638 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3639 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3640 } 3641 3642 return; 3643} 3644 3645void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3646 bool TypeContainsUndeducedAuto) { 3647 Decl *RealDecl = dcl.getAs<Decl>(); 3648 3649 // If there is no declaration, there was an error parsing it. Just ignore it. 3650 if (RealDecl == 0) 3651 return; 3652 3653 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3654 QualType Type = Var->getType(); 3655 3656 // Record tentative definitions. 3657 if (Var->isTentativeDefinition(Context)) { 3658 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3659 InsertPair = 3660 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3661 3662 // Keep the latest definition in the map. If we see 'int i; int i;' we 3663 // want the second one in the map. 3664 InsertPair.first->second = Var; 3665 3666 // However, for the list, we don't care about the order, just make sure 3667 // that there are no dupes for a given declaration name. 3668 if (InsertPair.second) 3669 TentativeDefinitionList.push_back(Var->getDeclName()); 3670 } 3671 3672 // C++ [dcl.init.ref]p3: 3673 // The initializer can be omitted for a reference only in a 3674 // parameter declaration (8.3.5), in the declaration of a 3675 // function return type, in the declaration of a class member 3676 // within its class declaration (9.2), and where the extern 3677 // specifier is explicitly used. 3678 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3679 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3680 << Var->getDeclName() 3681 << SourceRange(Var->getLocation(), Var->getLocation()); 3682 Var->setInvalidDecl(); 3683 return; 3684 } 3685 3686 // C++0x [dcl.spec.auto]p3 3687 if (TypeContainsUndeducedAuto) { 3688 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3689 << Var->getDeclName() << Type; 3690 Var->setInvalidDecl(); 3691 return; 3692 } 3693 3694 // An array without size is an incomplete type, and there are no special 3695 // rules in C++ to make such a definition acceptable. 3696 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3697 !Var->hasExternalStorage()) { 3698 Diag(Var->getLocation(), 3699 diag::err_typecheck_incomplete_array_needs_initializer); 3700 Var->setInvalidDecl(); 3701 return; 3702 } 3703 3704 // C++ [temp.expl.spec]p15: 3705 // An explicit specialization of a static data member of a template is a 3706 // definition if the declaration includes an initializer; otherwise, it 3707 // is a declaration. 3708 if (Var->isStaticDataMember() && 3709 Var->getInstantiatedFromStaticDataMember() && 3710 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3711 return; 3712 3713 // C++ [dcl.init]p9: 3714 // If no initializer is specified for an object, and the object 3715 // is of (possibly cv-qualified) non-POD class type (or array 3716 // thereof), the object shall be default-initialized; if the 3717 // object is of const-qualified type, the underlying class type 3718 // shall have a user-declared default constructor. 3719 // 3720 // FIXME: Diagnose the "user-declared default constructor" bit. 3721 if (getLangOptions().CPlusPlus) { 3722 QualType InitType = Type; 3723 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3724 InitType = Context.getBaseElementType(Array); 3725 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3726 InitType->isRecordType() && !InitType->isDependentType()) { 3727 if (!RequireCompleteType(Var->getLocation(), InitType, 3728 diag::err_invalid_incomplete_type_use)) { 3729 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3730 3731 CXXConstructorDecl *Constructor 3732 = PerformInitializationByConstructor(InitType, 3733 MultiExprArg(*this, 0, 0), 3734 Var->getLocation(), 3735 SourceRange(Var->getLocation(), 3736 Var->getLocation()), 3737 Var->getDeclName(), 3738 InitializationKind::CreateDefault(Var->getLocation()), 3739 ConstructorArgs); 3740 3741 // FIXME: Location info for the variable initialization? 3742 if (!Constructor) 3743 Var->setInvalidDecl(); 3744 else { 3745 // FIXME: Cope with initialization of arrays 3746 if (!Constructor->isTrivial() && 3747 InitializeVarWithConstructor(Var, Constructor, 3748 move_arg(ConstructorArgs))) 3749 Var->setInvalidDecl(); 3750 3751 FinalizeVarWithDestructor(Var, InitType); 3752 } 3753 } else { 3754 Var->setInvalidDecl(); 3755 } 3756 } 3757 3758 // The variable can not have an abstract class type. 3759 if (RequireNonAbstractType(Var->getLocation(), Type, 3760 diag::err_abstract_type_in_decl, 3761 AbstractVariableType)) 3762 Var->setInvalidDecl(); 3763 } 3764 3765#if 0 3766 // FIXME: Temporarily disabled because we are not properly parsing 3767 // linkage specifications on declarations, e.g., 3768 // 3769 // extern "C" const CGPoint CGPointerZero; 3770 // 3771 // C++ [dcl.init]p9: 3772 // 3773 // If no initializer is specified for an object, and the 3774 // object is of (possibly cv-qualified) non-POD class type (or 3775 // array thereof), the object shall be default-initialized; if 3776 // the object is of const-qualified type, the underlying class 3777 // type shall have a user-declared default 3778 // constructor. Otherwise, if no initializer is specified for 3779 // an object, the object and its subobjects, if any, have an 3780 // indeterminate initial value; if the object or any of its 3781 // subobjects are of const-qualified type, the program is 3782 // ill-formed. 3783 // 3784 // This isn't technically an error in C, so we don't diagnose it. 3785 // 3786 // FIXME: Actually perform the POD/user-defined default 3787 // constructor check. 3788 if (getLangOptions().CPlusPlus && 3789 Context.getCanonicalType(Type).isConstQualified() && 3790 !Var->hasExternalStorage()) 3791 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3792 << Var->getName() 3793 << SourceRange(Var->getLocation(), Var->getLocation()); 3794#endif 3795 } 3796} 3797 3798Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3799 DeclPtrTy *Group, 3800 unsigned NumDecls) { 3801 llvm::SmallVector<Decl*, 8> Decls; 3802 3803 if (DS.isTypeSpecOwned()) 3804 Decls.push_back((Decl*)DS.getTypeRep()); 3805 3806 for (unsigned i = 0; i != NumDecls; ++i) 3807 if (Decl *D = Group[i].getAs<Decl>()) 3808 Decls.push_back(D); 3809 3810 // Perform semantic analysis that depends on having fully processed both 3811 // the declarator and initializer. 3812 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3813 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3814 if (!IDecl) 3815 continue; 3816 QualType T = IDecl->getType(); 3817 3818 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3819 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3820 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3821 if (T->isDependentType()) { 3822 // If T is dependent, we should not require a complete type. 3823 // (RequireCompleteType shouldn't be called with dependent types.) 3824 // But we still can at least check if we've got an array of unspecified 3825 // size without an initializer. 3826 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3827 !IDecl->getInit()) { 3828 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3829 << T; 3830 IDecl->setInvalidDecl(); 3831 } 3832 } else if (!IDecl->isInvalidDecl()) { 3833 // If T is an incomplete array type with an initializer list that is 3834 // dependent on something, its size has not been fixed. We could attempt 3835 // to fix the size for such arrays, but we would still have to check 3836 // here for initializers containing a C++0x vararg expansion, e.g. 3837 // template <typename... Args> void f(Args... args) { 3838 // int vals[] = { args }; 3839 // } 3840 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3841 Expr *Init = IDecl->getInit(); 3842 if (IAT && Init && 3843 (Init->isTypeDependent() || Init->isValueDependent())) { 3844 // Check that the member type of the array is complete, at least. 3845 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3846 diag::err_typecheck_decl_incomplete_type)) 3847 IDecl->setInvalidDecl(); 3848 } else if (RequireCompleteType(IDecl->getLocation(), T, 3849 diag::err_typecheck_decl_incomplete_type)) 3850 IDecl->setInvalidDecl(); 3851 } 3852 } 3853 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3854 // object that has file scope without an initializer, and without a 3855 // storage-class specifier or with the storage-class specifier "static", 3856 // constitutes a tentative definition. Note: A tentative definition with 3857 // external linkage is valid (C99 6.2.2p5). 3858 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3859 if (const IncompleteArrayType *ArrayT 3860 = Context.getAsIncompleteArrayType(T)) { 3861 if (RequireCompleteType(IDecl->getLocation(), 3862 ArrayT->getElementType(), 3863 diag::err_illegal_decl_array_incomplete_type)) 3864 IDecl->setInvalidDecl(); 3865 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3866 // C99 6.9.2p3: If the declaration of an identifier for an object is 3867 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3868 // declared type shall not be an incomplete type. 3869 // NOTE: code such as the following 3870 // static struct s; 3871 // struct s { int a; }; 3872 // is accepted by gcc. Hence here we issue a warning instead of 3873 // an error and we do not invalidate the static declaration. 3874 // NOTE: to avoid multiple warnings, only check the first declaration. 3875 if (IDecl->getPreviousDeclaration() == 0) 3876 RequireCompleteType(IDecl->getLocation(), T, 3877 diag::ext_typecheck_decl_incomplete_type); 3878 } 3879 } 3880 } 3881 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3882 Decls.data(), Decls.size())); 3883} 3884 3885 3886/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3887/// to introduce parameters into function prototype scope. 3888Sema::DeclPtrTy 3889Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3890 const DeclSpec &DS = D.getDeclSpec(); 3891 3892 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3893 VarDecl::StorageClass StorageClass = VarDecl::None; 3894 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3895 StorageClass = VarDecl::Register; 3896 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3897 Diag(DS.getStorageClassSpecLoc(), 3898 diag::err_invalid_storage_class_in_func_decl); 3899 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3900 } 3901 3902 if (D.getDeclSpec().isThreadSpecified()) 3903 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3904 3905 DiagnoseFunctionSpecifiers(D); 3906 3907 // Check that there are no default arguments inside the type of this 3908 // parameter (C++ only). 3909 if (getLangOptions().CPlusPlus) 3910 CheckExtraCXXDefaultArguments(D); 3911 3912 TypeSourceInfo *TInfo = 0; 3913 TagDecl *OwnedDecl = 0; 3914 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3915 3916 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3917 // C++ [dcl.fct]p6: 3918 // Types shall not be defined in return or parameter types. 3919 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3920 << Context.getTypeDeclType(OwnedDecl); 3921 } 3922 3923 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3924 // Can this happen for params? We already checked that they don't conflict 3925 // among each other. Here they can only shadow globals, which is ok. 3926 IdentifierInfo *II = D.getIdentifier(); 3927 if (II) { 3928 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3929 if (PrevDecl->isTemplateParameter()) { 3930 // Maybe we will complain about the shadowed template parameter. 3931 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3932 // Just pretend that we didn't see the previous declaration. 3933 PrevDecl = 0; 3934 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3935 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3936 3937 // Recover by removing the name 3938 II = 0; 3939 D.SetIdentifier(0, D.getIdentifierLoc()); 3940 } 3941 } 3942 } 3943 3944 // Parameters can not be abstract class types. 3945 // For record types, this is done by the AbstractClassUsageDiagnoser once 3946 // the class has been completely parsed. 3947 if (!CurContext->isRecord() && 3948 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3949 diag::err_abstract_type_in_decl, 3950 AbstractParamType)) 3951 D.setInvalidType(true); 3952 3953 QualType T = adjustParameterType(parmDeclType); 3954 3955 ParmVarDecl *New 3956 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3957 T, TInfo, StorageClass, 0); 3958 3959 if (D.isInvalidType()) 3960 New->setInvalidDecl(); 3961 3962 // Parameter declarators cannot be interface types. All ObjC objects are 3963 // passed by reference. 3964 if (T->isObjCInterfaceType()) { 3965 Diag(D.getIdentifierLoc(), 3966 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3967 New->setInvalidDecl(); 3968 } 3969 3970 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3971 if (D.getCXXScopeSpec().isSet()) { 3972 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3973 << D.getCXXScopeSpec().getRange(); 3974 New->setInvalidDecl(); 3975 } 3976 3977 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3978 // duration shall not be qualified by an address-space qualifier." 3979 // Since all parameters have automatic store duration, they can not have 3980 // an address space. 3981 if (T.getAddressSpace() != 0) { 3982 Diag(D.getIdentifierLoc(), 3983 diag::err_arg_with_address_space); 3984 New->setInvalidDecl(); 3985 } 3986 3987 3988 // Add the parameter declaration into this scope. 3989 S->AddDecl(DeclPtrTy::make(New)); 3990 if (II) 3991 IdResolver.AddDecl(New); 3992 3993 ProcessDeclAttributes(S, New, D); 3994 3995 if (New->hasAttr<BlocksAttr>()) { 3996 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3997 } 3998 return DeclPtrTy::make(New); 3999} 4000 4001void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 4002 SourceLocation LocAfterDecls) { 4003 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4004 "Not a function declarator!"); 4005 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4006 4007 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4008 // for a K&R function. 4009 if (!FTI.hasPrototype) { 4010 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4011 --i; 4012 if (FTI.ArgInfo[i].Param == 0) { 4013 llvm::SmallString<256> Code; 4014 llvm::raw_svector_ostream(Code) << " int " 4015 << FTI.ArgInfo[i].Ident->getName() 4016 << ";\n"; 4017 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4018 << FTI.ArgInfo[i].Ident 4019 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4020 4021 // Implicitly declare the argument as type 'int' for lack of a better 4022 // type. 4023 DeclSpec DS; 4024 const char* PrevSpec; // unused 4025 unsigned DiagID; // unused 4026 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4027 PrevSpec, DiagID); 4028 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4029 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4030 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4031 } 4032 } 4033 } 4034} 4035 4036Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4037 Declarator &D) { 4038 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4039 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4040 "Not a function declarator!"); 4041 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4042 4043 if (FTI.hasPrototype) { 4044 // FIXME: Diagnose arguments without names in C. 4045 } 4046 4047 Scope *ParentScope = FnBodyScope->getParent(); 4048 4049 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4050 MultiTemplateParamsArg(*this), 4051 /*IsFunctionDefinition=*/true); 4052 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4053} 4054 4055static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4056 // Don't warn about invalid declarations. 4057 if (FD->isInvalidDecl()) 4058 return false; 4059 4060 // Or declarations that aren't global. 4061 if (!FD->isGlobal()) 4062 return false; 4063 4064 // Don't warn about C++ member functions. 4065 if (isa<CXXMethodDecl>(FD)) 4066 return false; 4067 4068 // Don't warn about 'main'. 4069 if (FD->isMain()) 4070 return false; 4071 4072 // Don't warn about inline functions. 4073 if (FD->isInlineSpecified()) 4074 return false; 4075 4076 // Don't warn about function templates. 4077 if (FD->getDescribedFunctionTemplate()) 4078 return false; 4079 4080 // Don't warn about function template specializations. 4081 if (FD->isFunctionTemplateSpecialization()) 4082 return false; 4083 4084 bool MissingPrototype = true; 4085 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4086 Prev; Prev = Prev->getPreviousDeclaration()) { 4087 // Ignore any declarations that occur in function or method 4088 // scope, because they aren't visible from the header. 4089 if (Prev->getDeclContext()->isFunctionOrMethod()) 4090 continue; 4091 4092 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4093 break; 4094 } 4095 4096 return MissingPrototype; 4097} 4098 4099Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4100 // Clear the last template instantiation error context. 4101 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4102 4103 if (!D) 4104 return D; 4105 FunctionDecl *FD = 0; 4106 4107 if (FunctionTemplateDecl *FunTmpl 4108 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4109 FD = FunTmpl->getTemplatedDecl(); 4110 else 4111 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4112 4113 CurFunctionNeedsScopeChecking = false; 4114 4115 // See if this is a redefinition. 4116 const FunctionDecl *Definition; 4117 if (FD->getBody(Definition)) { 4118 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4119 Diag(Definition->getLocation(), diag::note_previous_definition); 4120 } 4121 4122 // Builtin functions cannot be defined. 4123 if (unsigned BuiltinID = FD->getBuiltinID()) { 4124 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4125 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4126 FD->setInvalidDecl(); 4127 } 4128 } 4129 4130 // The return type of a function definition must be complete 4131 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4132 QualType ResultType = FD->getResultType(); 4133 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4134 !FD->isInvalidDecl() && 4135 RequireCompleteType(FD->getLocation(), ResultType, 4136 diag::err_func_def_incomplete_result)) 4137 FD->setInvalidDecl(); 4138 4139 // GNU warning -Wmissing-prototypes: 4140 // Warn if a global function is defined without a previous 4141 // prototype declaration. This warning is issued even if the 4142 // definition itself provides a prototype. The aim is to detect 4143 // global functions that fail to be declared in header files. 4144 if (ShouldWarnAboutMissingPrototype(FD)) 4145 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4146 4147 if (FnBodyScope) 4148 PushDeclContext(FnBodyScope, FD); 4149 4150 // Check the validity of our function parameters 4151 CheckParmsForFunctionDef(FD); 4152 4153 // Introduce our parameters into the function scope 4154 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4155 ParmVarDecl *Param = FD->getParamDecl(p); 4156 Param->setOwningFunction(FD); 4157 4158 // If this has an identifier, add it to the scope stack. 4159 if (Param->getIdentifier() && FnBodyScope) 4160 PushOnScopeChains(Param, FnBodyScope); 4161 } 4162 4163 // Checking attributes of current function definition 4164 // dllimport attribute. 4165 if (FD->getAttr<DLLImportAttr>() && 4166 (!FD->getAttr<DLLExportAttr>())) { 4167 // dllimport attribute cannot be applied to definition. 4168 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4169 Diag(FD->getLocation(), 4170 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4171 << "dllimport"; 4172 FD->setInvalidDecl(); 4173 return DeclPtrTy::make(FD); 4174 } else { 4175 // If a symbol previously declared dllimport is later defined, the 4176 // attribute is ignored in subsequent references, and a warning is 4177 // emitted. 4178 Diag(FD->getLocation(), 4179 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4180 << FD->getNameAsCString() << "dllimport"; 4181 } 4182 } 4183 return DeclPtrTy::make(FD); 4184} 4185 4186Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4187 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4188} 4189 4190Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4191 bool IsInstantiation) { 4192 Decl *dcl = D.getAs<Decl>(); 4193 Stmt *Body = BodyArg.takeAs<Stmt>(); 4194 4195 FunctionDecl *FD = 0; 4196 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4197 if (FunTmpl) 4198 FD = FunTmpl->getTemplatedDecl(); 4199 else 4200 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4201 4202 if (FD) { 4203 FD->setBody(Body); 4204 if (FD->isMain()) 4205 // C and C++ allow for main to automagically return 0. 4206 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4207 FD->setHasImplicitReturnZero(true); 4208 else 4209 CheckFallThroughForFunctionDef(FD, Body); 4210 4211 if (!FD->isInvalidDecl()) 4212 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4213 4214 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4215 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4216 4217 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4218 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4219 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4220 MD->setBody(Body); 4221 CheckFallThroughForFunctionDef(MD, Body); 4222 MD->setEndLoc(Body->getLocEnd()); 4223 4224 if (!MD->isInvalidDecl()) 4225 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4226 } else { 4227 Body->Destroy(Context); 4228 return DeclPtrTy(); 4229 } 4230 if (!IsInstantiation) 4231 PopDeclContext(); 4232 4233 // Verify and clean out per-function state. 4234 4235 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4236 4237 // Check goto/label use. 4238 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4239 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4240 LabelStmt *L = I->second; 4241 4242 // Verify that we have no forward references left. If so, there was a goto 4243 // or address of a label taken, but no definition of it. Label fwd 4244 // definitions are indicated with a null substmt. 4245 if (L->getSubStmt() != 0) 4246 continue; 4247 4248 // Emit error. 4249 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4250 4251 // At this point, we have gotos that use the bogus label. Stitch it into 4252 // the function body so that they aren't leaked and that the AST is well 4253 // formed. 4254 if (Body == 0) { 4255 // The whole function wasn't parsed correctly, just delete this. 4256 L->Destroy(Context); 4257 continue; 4258 } 4259 4260 // Otherwise, the body is valid: we want to stitch the label decl into the 4261 // function somewhere so that it is properly owned and so that the goto 4262 // has a valid target. Do this by creating a new compound stmt with the 4263 // label in it. 4264 4265 // Give the label a sub-statement. 4266 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4267 4268 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4269 cast<CXXTryStmt>(Body)->getTryBlock() : 4270 cast<CompoundStmt>(Body); 4271 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4272 Elements.push_back(L); 4273 Compound->setStmts(Context, &Elements[0], Elements.size()); 4274 } 4275 FunctionLabelMap.clear(); 4276 4277 if (!Body) return D; 4278 4279 // Verify that that gotos and switch cases don't jump into scopes illegally. 4280 if (CurFunctionNeedsScopeChecking) 4281 DiagnoseInvalidJumps(Body); 4282 4283 // C++ constructors that have function-try-blocks can't have return 4284 // statements in the handlers of that block. (C++ [except.handle]p14) 4285 // Verify this. 4286 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4287 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4288 4289 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4290 MarkBaseAndMemberDestructorsReferenced(Destructor); 4291 4292 // If any errors have occurred, clear out any temporaries that may have 4293 // been leftover. This ensures that these temporaries won't be picked up for 4294 // deletion in some later function. 4295 if (PP.getDiagnostics().hasErrorOccurred()) 4296 ExprTemporaries.clear(); 4297 4298 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4299 return D; 4300} 4301 4302/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4303/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4304NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4305 IdentifierInfo &II, Scope *S) { 4306 // Before we produce a declaration for an implicitly defined 4307 // function, see whether there was a locally-scoped declaration of 4308 // this name as a function or variable. If so, use that 4309 // (non-visible) declaration, and complain about it. 4310 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4311 = LocallyScopedExternalDecls.find(&II); 4312 if (Pos != LocallyScopedExternalDecls.end()) { 4313 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4314 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4315 return Pos->second; 4316 } 4317 4318 // Extension in C99. Legal in C90, but warn about it. 4319 if (II.getName().startswith("__builtin_")) 4320 Diag(Loc, diag::warn_builtin_unknown) << &II; 4321 else if (getLangOptions().C99) 4322 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4323 else 4324 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4325 4326 // Set a Declarator for the implicit definition: int foo(); 4327 const char *Dummy; 4328 DeclSpec DS; 4329 unsigned DiagID; 4330 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4331 Error = Error; // Silence warning. 4332 assert(!Error && "Error setting up implicit decl!"); 4333 Declarator D(DS, Declarator::BlockContext); 4334 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4335 0, 0, false, SourceLocation(), 4336 false, 0,0,0, Loc, Loc, D), 4337 SourceLocation()); 4338 D.SetIdentifier(&II, Loc); 4339 4340 // Insert this function into translation-unit scope. 4341 4342 DeclContext *PrevDC = CurContext; 4343 CurContext = Context.getTranslationUnitDecl(); 4344 4345 FunctionDecl *FD = 4346 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4347 FD->setImplicit(); 4348 4349 CurContext = PrevDC; 4350 4351 AddKnownFunctionAttributes(FD); 4352 4353 return FD; 4354} 4355 4356/// \brief Adds any function attributes that we know a priori based on 4357/// the declaration of this function. 4358/// 4359/// These attributes can apply both to implicitly-declared builtins 4360/// (like __builtin___printf_chk) or to library-declared functions 4361/// like NSLog or printf. 4362void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4363 if (FD->isInvalidDecl()) 4364 return; 4365 4366 // If this is a built-in function, map its builtin attributes to 4367 // actual attributes. 4368 if (unsigned BuiltinID = FD->getBuiltinID()) { 4369 // Handle printf-formatting attributes. 4370 unsigned FormatIdx; 4371 bool HasVAListArg; 4372 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4373 if (!FD->getAttr<FormatAttr>()) 4374 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4375 HasVAListArg ? 0 : FormatIdx + 2)); 4376 } 4377 4378 // Mark const if we don't care about errno and that is the only 4379 // thing preventing the function from being const. This allows 4380 // IRgen to use LLVM intrinsics for such functions. 4381 if (!getLangOptions().MathErrno && 4382 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4383 if (!FD->getAttr<ConstAttr>()) 4384 FD->addAttr(::new (Context) ConstAttr()); 4385 } 4386 4387 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4388 FD->addAttr(::new (Context) NoReturnAttr()); 4389 } 4390 4391 IdentifierInfo *Name = FD->getIdentifier(); 4392 if (!Name) 4393 return; 4394 if ((!getLangOptions().CPlusPlus && 4395 FD->getDeclContext()->isTranslationUnit()) || 4396 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4397 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4398 LinkageSpecDecl::lang_c)) { 4399 // Okay: this could be a libc/libm/Objective-C function we know 4400 // about. 4401 } else 4402 return; 4403 4404 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4405 // FIXME: NSLog and NSLogv should be target specific 4406 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4407 // FIXME: We known better than our headers. 4408 const_cast<FormatAttr *>(Format)->setType("printf"); 4409 } else 4410 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4411 Name->isStr("NSLogv") ? 0 : 2)); 4412 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4413 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4414 // target-specific builtins, perhaps? 4415 if (!FD->getAttr<FormatAttr>()) 4416 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4417 Name->isStr("vasprintf") ? 0 : 3)); 4418 } 4419} 4420 4421TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4422 TypeSourceInfo *TInfo) { 4423 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4424 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4425 4426 if (!TInfo) { 4427 assert(D.isInvalidType() && "no declarator info for valid type"); 4428 TInfo = Context.getTrivialTypeSourceInfo(T); 4429 } 4430 4431 // Scope manipulation handled by caller. 4432 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4433 D.getIdentifierLoc(), 4434 D.getIdentifier(), 4435 TInfo); 4436 4437 if (const TagType *TT = T->getAs<TagType>()) { 4438 TagDecl *TD = TT->getDecl(); 4439 4440 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4441 // keep track of the TypedefDecl. 4442 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4443 TD->setTypedefForAnonDecl(NewTD); 4444 } 4445 4446 if (D.isInvalidType()) 4447 NewTD->setInvalidDecl(); 4448 return NewTD; 4449} 4450 4451 4452/// \brief Determine whether a tag with a given kind is acceptable 4453/// as a redeclaration of the given tag declaration. 4454/// 4455/// \returns true if the new tag kind is acceptable, false otherwise. 4456bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4457 TagDecl::TagKind NewTag, 4458 SourceLocation NewTagLoc, 4459 const IdentifierInfo &Name) { 4460 // C++ [dcl.type.elab]p3: 4461 // The class-key or enum keyword present in the 4462 // elaborated-type-specifier shall agree in kind with the 4463 // declaration to which the name in theelaborated-type-specifier 4464 // refers. This rule also applies to the form of 4465 // elaborated-type-specifier that declares a class-name or 4466 // friend class since it can be construed as referring to the 4467 // definition of the class. Thus, in any 4468 // elaborated-type-specifier, the enum keyword shall be used to 4469 // refer to an enumeration (7.2), the union class-keyshall be 4470 // used to refer to a union (clause 9), and either the class or 4471 // struct class-key shall be used to refer to a class (clause 9) 4472 // declared using the class or struct class-key. 4473 TagDecl::TagKind OldTag = Previous->getTagKind(); 4474 if (OldTag == NewTag) 4475 return true; 4476 4477 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4478 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4479 // Warn about the struct/class tag mismatch. 4480 bool isTemplate = false; 4481 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4482 isTemplate = Record->getDescribedClassTemplate(); 4483 4484 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4485 << (NewTag == TagDecl::TK_class) 4486 << isTemplate << &Name 4487 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4488 OldTag == TagDecl::TK_class? "class" : "struct"); 4489 Diag(Previous->getLocation(), diag::note_previous_use); 4490 return true; 4491 } 4492 return false; 4493} 4494 4495/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4496/// former case, Name will be non-null. In the later case, Name will be null. 4497/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4498/// reference/declaration/definition of a tag. 4499Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4500 SourceLocation KWLoc, const CXXScopeSpec &SS, 4501 IdentifierInfo *Name, SourceLocation NameLoc, 4502 AttributeList *Attr, AccessSpecifier AS, 4503 MultiTemplateParamsArg TemplateParameterLists, 4504 bool &OwnedDecl, bool &IsDependent) { 4505 // If this is not a definition, it must have a name. 4506 assert((Name != 0 || TUK == TUK_Definition) && 4507 "Nameless record must be a definition!"); 4508 4509 OwnedDecl = false; 4510 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4511 4512 // FIXME: Check explicit specializations more carefully. 4513 bool isExplicitSpecialization = false; 4514 if (TUK != TUK_Reference) { 4515 if (TemplateParameterList *TemplateParams 4516 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4517 (TemplateParameterList**)TemplateParameterLists.get(), 4518 TemplateParameterLists.size(), 4519 isExplicitSpecialization)) { 4520 if (TemplateParams->size() > 0) { 4521 // This is a declaration or definition of a class template (which may 4522 // be a member of another template). 4523 OwnedDecl = false; 4524 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4525 SS, Name, NameLoc, Attr, 4526 TemplateParams, 4527 AS); 4528 TemplateParameterLists.release(); 4529 return Result.get(); 4530 } else { 4531 // The "template<>" header is extraneous. 4532 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4533 << ElaboratedType::getNameForTagKind(Kind) << Name; 4534 isExplicitSpecialization = true; 4535 } 4536 } 4537 4538 TemplateParameterLists.release(); 4539 } 4540 4541 DeclContext *SearchDC = CurContext; 4542 DeclContext *DC = CurContext; 4543 bool isStdBadAlloc = false; 4544 bool Invalid = false; 4545 4546 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4547 : NotForRedeclaration); 4548 4549 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4550 4551 if (Name && SS.isNotEmpty()) { 4552 // We have a nested-name tag ('struct foo::bar'). 4553 4554 // Check for invalid 'foo::'. 4555 if (SS.isInvalid()) { 4556 Name = 0; 4557 goto CreateNewDecl; 4558 } 4559 4560 // If this is a friend or a reference to a class in a dependent 4561 // context, don't try to make a decl for it. 4562 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4563 DC = computeDeclContext(SS, false); 4564 if (!DC) { 4565 IsDependent = true; 4566 return DeclPtrTy(); 4567 } 4568 } 4569 4570 if (RequireCompleteDeclContext(SS)) 4571 return DeclPtrTy::make((Decl *)0); 4572 4573 DC = computeDeclContext(SS, true); 4574 SearchDC = DC; 4575 // Look-up name inside 'foo::'. 4576 LookupQualifiedName(Previous, DC); 4577 4578 if (Previous.isAmbiguous()) 4579 return DeclPtrTy(); 4580 4581 // A tag 'foo::bar' must already exist. 4582 if (Previous.empty()) { 4583 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4584 Name = 0; 4585 Invalid = true; 4586 goto CreateNewDecl; 4587 } 4588 } else if (Name) { 4589 // If this is a named struct, check to see if there was a previous forward 4590 // declaration or definition. 4591 // FIXME: We're looking into outer scopes here, even when we 4592 // shouldn't be. Doing so can result in ambiguities that we 4593 // shouldn't be diagnosing. 4594 LookupName(Previous, S); 4595 4596 // Note: there used to be some attempt at recovery here. 4597 if (Previous.isAmbiguous()) 4598 return DeclPtrTy(); 4599 4600 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4601 // FIXME: This makes sure that we ignore the contexts associated 4602 // with C structs, unions, and enums when looking for a matching 4603 // tag declaration or definition. See the similar lookup tweak 4604 // in Sema::LookupName; is there a better way to deal with this? 4605 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4606 SearchDC = SearchDC->getParent(); 4607 } 4608 } 4609 4610 if (Previous.isSingleResult() && 4611 Previous.getFoundDecl()->isTemplateParameter()) { 4612 // Maybe we will complain about the shadowed template parameter. 4613 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4614 // Just pretend that we didn't see the previous declaration. 4615 Previous.clear(); 4616 } 4617 4618 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4619 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4620 // This is a declaration of or a reference to "std::bad_alloc". 4621 isStdBadAlloc = true; 4622 4623 if (Previous.empty() && StdBadAlloc) { 4624 // std::bad_alloc has been implicitly declared (but made invisible to 4625 // name lookup). Fill in this implicit declaration as the previous 4626 // declaration, so that the declarations get chained appropriately. 4627 Previous.addDecl(StdBadAlloc); 4628 } 4629 } 4630 4631 if (!Previous.empty()) { 4632 assert(Previous.isSingleResult()); 4633 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4634 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4635 // If this is a use of a previous tag, or if the tag is already declared 4636 // in the same scope (so that the definition/declaration completes or 4637 // rementions the tag), reuse the decl. 4638 if (TUK == TUK_Reference || TUK == TUK_Friend || 4639 isDeclInScope(PrevDecl, SearchDC, S)) { 4640 // Make sure that this wasn't declared as an enum and now used as a 4641 // struct or something similar. 4642 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4643 bool SafeToContinue 4644 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4645 Kind != TagDecl::TK_enum); 4646 if (SafeToContinue) 4647 Diag(KWLoc, diag::err_use_with_wrong_tag) 4648 << Name 4649 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4650 PrevTagDecl->getKindName()); 4651 else 4652 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4653 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4654 4655 if (SafeToContinue) 4656 Kind = PrevTagDecl->getTagKind(); 4657 else { 4658 // Recover by making this an anonymous redefinition. 4659 Name = 0; 4660 Previous.clear(); 4661 Invalid = true; 4662 } 4663 } 4664 4665 if (!Invalid) { 4666 // If this is a use, just return the declaration we found. 4667 4668 // FIXME: In the future, return a variant or some other clue 4669 // for the consumer of this Decl to know it doesn't own it. 4670 // For our current ASTs this shouldn't be a problem, but will 4671 // need to be changed with DeclGroups. 4672 if (TUK == TUK_Reference || TUK == TUK_Friend) 4673 return DeclPtrTy::make(PrevTagDecl); 4674 4675 // Diagnose attempts to redefine a tag. 4676 if (TUK == TUK_Definition) { 4677 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4678 // If we're defining a specialization and the previous definition 4679 // is from an implicit instantiation, don't emit an error 4680 // here; we'll catch this in the general case below. 4681 if (!isExplicitSpecialization || 4682 !isa<CXXRecordDecl>(Def) || 4683 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4684 == TSK_ExplicitSpecialization) { 4685 Diag(NameLoc, diag::err_redefinition) << Name; 4686 Diag(Def->getLocation(), diag::note_previous_definition); 4687 // If this is a redefinition, recover by making this 4688 // struct be anonymous, which will make any later 4689 // references get the previous definition. 4690 Name = 0; 4691 Previous.clear(); 4692 Invalid = true; 4693 } 4694 } else { 4695 // If the type is currently being defined, complain 4696 // about a nested redefinition. 4697 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4698 if (Tag->isBeingDefined()) { 4699 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4700 Diag(PrevTagDecl->getLocation(), 4701 diag::note_previous_definition); 4702 Name = 0; 4703 Previous.clear(); 4704 Invalid = true; 4705 } 4706 } 4707 4708 // Okay, this is definition of a previously declared or referenced 4709 // tag PrevDecl. We're going to create a new Decl for it. 4710 } 4711 } 4712 // If we get here we have (another) forward declaration or we 4713 // have a definition. Just create a new decl. 4714 4715 } else { 4716 // If we get here, this is a definition of a new tag type in a nested 4717 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4718 // new decl/type. We set PrevDecl to NULL so that the entities 4719 // have distinct types. 4720 Previous.clear(); 4721 } 4722 // If we get here, we're going to create a new Decl. If PrevDecl 4723 // is non-NULL, it's a definition of the tag declared by 4724 // PrevDecl. If it's NULL, we have a new definition. 4725 } else { 4726 // PrevDecl is a namespace, template, or anything else 4727 // that lives in the IDNS_Tag identifier namespace. 4728 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4729 // The tag name clashes with a namespace name, issue an error and 4730 // recover by making this tag be anonymous. 4731 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4732 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4733 Name = 0; 4734 Previous.clear(); 4735 Invalid = true; 4736 } else { 4737 // The existing declaration isn't relevant to us; we're in a 4738 // new scope, so clear out the previous declaration. 4739 Previous.clear(); 4740 } 4741 } 4742 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4743 // C++ [basic.scope.pdecl]p5: 4744 // -- for an elaborated-type-specifier of the form 4745 // 4746 // class-key identifier 4747 // 4748 // if the elaborated-type-specifier is used in the 4749 // decl-specifier-seq or parameter-declaration-clause of a 4750 // function defined in namespace scope, the identifier is 4751 // declared as a class-name in the namespace that contains 4752 // the declaration; otherwise, except as a friend 4753 // declaration, the identifier is declared in the smallest 4754 // non-class, non-function-prototype scope that contains the 4755 // declaration. 4756 // 4757 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4758 // C structs and unions. 4759 // 4760 // It is an error in C++ to declare (rather than define) an enum 4761 // type, including via an elaborated type specifier. We'll 4762 // diagnose that later; for now, declare the enum in the same 4763 // scope as we would have picked for any other tag type. 4764 // 4765 // GNU C also supports this behavior as part of its incomplete 4766 // enum types extension, while GNU C++ does not. 4767 // 4768 // Find the context where we'll be declaring the tag. 4769 // FIXME: We would like to maintain the current DeclContext as the 4770 // lexical context, 4771 while (SearchDC->isRecord()) 4772 SearchDC = SearchDC->getParent(); 4773 4774 // Find the scope where we'll be declaring the tag. 4775 while (S->isClassScope() || 4776 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4777 ((S->getFlags() & Scope::DeclScope) == 0) || 4778 (S->getEntity() && 4779 ((DeclContext *)S->getEntity())->isTransparentContext())) 4780 S = S->getParent(); 4781 4782 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4783 // C++ [namespace.memdef]p3: 4784 // If a friend declaration in a non-local class first declares a 4785 // class or function, the friend class or function is a member of 4786 // the innermost enclosing namespace. 4787 while (!SearchDC->isFileContext()) 4788 SearchDC = SearchDC->getParent(); 4789 4790 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4791 while (S->getEntity() != SearchDC) 4792 S = S->getParent(); 4793 } 4794 4795CreateNewDecl: 4796 4797 TagDecl *PrevDecl = 0; 4798 if (Previous.isSingleResult()) 4799 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4800 4801 // If there is an identifier, use the location of the identifier as the 4802 // location of the decl, otherwise use the location of the struct/union 4803 // keyword. 4804 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4805 4806 // Otherwise, create a new declaration. If there is a previous 4807 // declaration of the same entity, the two will be linked via 4808 // PrevDecl. 4809 TagDecl *New; 4810 4811 if (Kind == TagDecl::TK_enum) { 4812 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4813 // enum X { A, B, C } D; D should chain to X. 4814 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4815 cast_or_null<EnumDecl>(PrevDecl)); 4816 // If this is an undefined enum, warn. 4817 if (TUK != TUK_Definition && !Invalid) { 4818 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4819 : diag::ext_forward_ref_enum; 4820 Diag(Loc, DK); 4821 } 4822 } else { 4823 // struct/union/class 4824 4825 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4826 // struct X { int A; } D; D should chain to X. 4827 if (getLangOptions().CPlusPlus) { 4828 // FIXME: Look for a way to use RecordDecl for simple structs. 4829 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4830 cast_or_null<CXXRecordDecl>(PrevDecl)); 4831 4832 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4833 StdBadAlloc = cast<CXXRecordDecl>(New); 4834 } else 4835 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4836 cast_or_null<RecordDecl>(PrevDecl)); 4837 } 4838 4839 if (Kind != TagDecl::TK_enum) { 4840 // Handle #pragma pack: if the #pragma pack stack has non-default 4841 // alignment, make up a packed attribute for this decl. These 4842 // attributes are checked when the ASTContext lays out the 4843 // structure. 4844 // 4845 // It is important for implementing the correct semantics that this 4846 // happen here (in act on tag decl). The #pragma pack stack is 4847 // maintained as a result of parser callbacks which can occur at 4848 // many points during the parsing of a struct declaration (because 4849 // the #pragma tokens are effectively skipped over during the 4850 // parsing of the struct). 4851 if (unsigned Alignment = getPragmaPackAlignment()) 4852 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4853 } 4854 4855 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4856 // C++ [dcl.typedef]p3: 4857 // [...] Similarly, in a given scope, a class or enumeration 4858 // shall not be declared with the same name as a typedef-name 4859 // that is declared in that scope and refers to a type other 4860 // than the class or enumeration itself. 4861 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4862 ForRedeclaration); 4863 LookupName(Lookup, S); 4864 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4865 NamedDecl *PrevTypedefNamed = PrevTypedef; 4866 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4867 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4868 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4869 Diag(Loc, diag::err_tag_definition_of_typedef) 4870 << Context.getTypeDeclType(New) 4871 << PrevTypedef->getUnderlyingType(); 4872 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4873 Invalid = true; 4874 } 4875 } 4876 4877 // If this is a specialization of a member class (of a class template), 4878 // check the specialization. 4879 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4880 Invalid = true; 4881 4882 if (Invalid) 4883 New->setInvalidDecl(); 4884 4885 if (Attr) 4886 ProcessDeclAttributeList(S, New, Attr); 4887 4888 // If we're declaring or defining a tag in function prototype scope 4889 // in C, note that this type can only be used within the function. 4890 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4891 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4892 4893 // Set the lexical context. If the tag has a C++ scope specifier, the 4894 // lexical context will be different from the semantic context. 4895 New->setLexicalDeclContext(CurContext); 4896 4897 // Mark this as a friend decl if applicable. 4898 if (TUK == TUK_Friend) 4899 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4900 4901 // Set the access specifier. 4902 if (!Invalid && TUK != TUK_Friend) 4903 SetMemberAccessSpecifier(New, PrevDecl, AS); 4904 4905 if (TUK == TUK_Definition) 4906 New->startDefinition(); 4907 4908 // If this has an identifier, add it to the scope stack. 4909 if (TUK == TUK_Friend) { 4910 // We might be replacing an existing declaration in the lookup tables; 4911 // if so, borrow its access specifier. 4912 if (PrevDecl) 4913 New->setAccess(PrevDecl->getAccess()); 4914 4915 // Friend tag decls are visible in fairly strange ways. 4916 if (!CurContext->isDependentContext()) { 4917 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4918 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4919 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4920 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4921 } 4922 } else if (Name) { 4923 S = getNonFieldDeclScope(S); 4924 PushOnScopeChains(New, S); 4925 } else { 4926 CurContext->addDecl(New); 4927 } 4928 4929 // If this is the C FILE type, notify the AST context. 4930 if (IdentifierInfo *II = New->getIdentifier()) 4931 if (!New->isInvalidDecl() && 4932 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4933 II->isStr("FILE")) 4934 Context.setFILEDecl(New); 4935 4936 OwnedDecl = true; 4937 return DeclPtrTy::make(New); 4938} 4939 4940void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4941 AdjustDeclIfTemplate(TagD); 4942 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4943 4944 // Enter the tag context. 4945 PushDeclContext(S, Tag); 4946 4947 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4948 FieldCollector->StartClass(); 4949 4950 if (Record->getIdentifier()) { 4951 // C++ [class]p2: 4952 // [...] The class-name is also inserted into the scope of the 4953 // class itself; this is known as the injected-class-name. For 4954 // purposes of access checking, the injected-class-name is treated 4955 // as if it were a public member name. 4956 CXXRecordDecl *InjectedClassName 4957 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4958 CurContext, Record->getLocation(), 4959 Record->getIdentifier(), 4960 Record->getTagKeywordLoc(), 4961 Record); 4962 InjectedClassName->setImplicit(); 4963 InjectedClassName->setAccess(AS_public); 4964 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4965 InjectedClassName->setDescribedClassTemplate(Template); 4966 PushOnScopeChains(InjectedClassName, S); 4967 assert(InjectedClassName->isInjectedClassName() && 4968 "Broken injected-class-name"); 4969 } 4970 } 4971} 4972 4973void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4974 SourceLocation RBraceLoc) { 4975 AdjustDeclIfTemplate(TagD); 4976 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4977 Tag->setRBraceLoc(RBraceLoc); 4978 4979 if (isa<CXXRecordDecl>(Tag)) 4980 FieldCollector->FinishClass(); 4981 4982 // Exit this scope of this tag's definition. 4983 PopDeclContext(); 4984 4985 // Notify the consumer that we've defined a tag. 4986 Consumer.HandleTagDeclDefinition(Tag); 4987} 4988 4989// Note that FieldName may be null for anonymous bitfields. 4990bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4991 QualType FieldTy, const Expr *BitWidth, 4992 bool *ZeroWidth) { 4993 // Default to true; that shouldn't confuse checks for emptiness 4994 if (ZeroWidth) 4995 *ZeroWidth = true; 4996 4997 // C99 6.7.2.1p4 - verify the field type. 4998 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4999 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 5000 // Handle incomplete types with specific error. 5001 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 5002 return true; 5003 if (FieldName) 5004 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 5005 << FieldName << FieldTy << BitWidth->getSourceRange(); 5006 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 5007 << FieldTy << BitWidth->getSourceRange(); 5008 } 5009 5010 // If the bit-width is type- or value-dependent, don't try to check 5011 // it now. 5012 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5013 return false; 5014 5015 llvm::APSInt Value; 5016 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5017 return true; 5018 5019 if (Value != 0 && ZeroWidth) 5020 *ZeroWidth = false; 5021 5022 // Zero-width bitfield is ok for anonymous field. 5023 if (Value == 0 && FieldName) 5024 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5025 5026 if (Value.isSigned() && Value.isNegative()) { 5027 if (FieldName) 5028 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5029 << FieldName << Value.toString(10); 5030 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5031 << Value.toString(10); 5032 } 5033 5034 if (!FieldTy->isDependentType()) { 5035 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5036 if (Value.getZExtValue() > TypeSize) { 5037 if (FieldName) 5038 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5039 << FieldName << (unsigned)TypeSize; 5040 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5041 << (unsigned)TypeSize; 5042 } 5043 } 5044 5045 return false; 5046} 5047 5048/// ActOnField - Each field of a struct/union/class is passed into this in order 5049/// to create a FieldDecl object for it. 5050Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5051 SourceLocation DeclStart, 5052 Declarator &D, ExprTy *BitfieldWidth) { 5053 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5054 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5055 AS_public); 5056 return DeclPtrTy::make(Res); 5057} 5058 5059/// HandleField - Analyze a field of a C struct or a C++ data member. 5060/// 5061FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5062 SourceLocation DeclStart, 5063 Declarator &D, Expr *BitWidth, 5064 AccessSpecifier AS) { 5065 IdentifierInfo *II = D.getIdentifier(); 5066 SourceLocation Loc = DeclStart; 5067 if (II) Loc = D.getIdentifierLoc(); 5068 5069 TypeSourceInfo *TInfo = 0; 5070 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5071 if (getLangOptions().CPlusPlus) 5072 CheckExtraCXXDefaultArguments(D); 5073 5074 DiagnoseFunctionSpecifiers(D); 5075 5076 if (D.getDeclSpec().isThreadSpecified()) 5077 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5078 5079 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5080 ForRedeclaration); 5081 5082 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5083 // Maybe we will complain about the shadowed template parameter. 5084 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5085 // Just pretend that we didn't see the previous declaration. 5086 PrevDecl = 0; 5087 } 5088 5089 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5090 PrevDecl = 0; 5091 5092 bool Mutable 5093 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5094 SourceLocation TSSL = D.getSourceRange().getBegin(); 5095 FieldDecl *NewFD 5096 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5097 AS, PrevDecl, &D); 5098 if (NewFD->isInvalidDecl() && PrevDecl) { 5099 // Don't introduce NewFD into scope; there's already something 5100 // with the same name in the same scope. 5101 } else if (II) { 5102 PushOnScopeChains(NewFD, S); 5103 } else 5104 Record->addDecl(NewFD); 5105 5106 return NewFD; 5107} 5108 5109/// \brief Build a new FieldDecl and check its well-formedness. 5110/// 5111/// This routine builds a new FieldDecl given the fields name, type, 5112/// record, etc. \p PrevDecl should refer to any previous declaration 5113/// with the same name and in the same scope as the field to be 5114/// created. 5115/// 5116/// \returns a new FieldDecl. 5117/// 5118/// \todo The Declarator argument is a hack. It will be removed once 5119FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5120 TypeSourceInfo *TInfo, 5121 RecordDecl *Record, SourceLocation Loc, 5122 bool Mutable, Expr *BitWidth, 5123 SourceLocation TSSL, 5124 AccessSpecifier AS, NamedDecl *PrevDecl, 5125 Declarator *D) { 5126 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5127 bool InvalidDecl = false; 5128 if (D) InvalidDecl = D->isInvalidType(); 5129 5130 // If we receive a broken type, recover by assuming 'int' and 5131 // marking this declaration as invalid. 5132 if (T.isNull()) { 5133 InvalidDecl = true; 5134 T = Context.IntTy; 5135 } 5136 5137 QualType EltTy = Context.getBaseElementType(T); 5138 if (!EltTy->isDependentType() && 5139 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5140 InvalidDecl = true; 5141 5142 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5143 // than a variably modified type. 5144 if (!InvalidDecl && T->isVariablyModifiedType()) { 5145 bool SizeIsNegative; 5146 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5147 SizeIsNegative); 5148 if (!FixedTy.isNull()) { 5149 Diag(Loc, diag::warn_illegal_constant_array_size); 5150 T = FixedTy; 5151 } else { 5152 if (SizeIsNegative) 5153 Diag(Loc, diag::err_typecheck_negative_array_size); 5154 else 5155 Diag(Loc, diag::err_typecheck_field_variable_size); 5156 InvalidDecl = true; 5157 } 5158 } 5159 5160 // Fields can not have abstract class types 5161 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5162 diag::err_abstract_type_in_decl, 5163 AbstractFieldType)) 5164 InvalidDecl = true; 5165 5166 bool ZeroWidth = false; 5167 // If this is declared as a bit-field, check the bit-field. 5168 if (!InvalidDecl && BitWidth && 5169 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5170 InvalidDecl = true; 5171 DeleteExpr(BitWidth); 5172 BitWidth = 0; 5173 ZeroWidth = false; 5174 } 5175 5176 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5177 BitWidth, Mutable); 5178 if (InvalidDecl) 5179 NewFD->setInvalidDecl(); 5180 5181 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5182 Diag(Loc, diag::err_duplicate_member) << II; 5183 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5184 NewFD->setInvalidDecl(); 5185 } 5186 5187 if (getLangOptions().CPlusPlus) { 5188 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5189 5190 if (!T->isPODType()) 5191 CXXRecord->setPOD(false); 5192 if (!ZeroWidth) 5193 CXXRecord->setEmpty(false); 5194 5195 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5196 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5197 5198 if (!RDecl->hasTrivialConstructor()) 5199 CXXRecord->setHasTrivialConstructor(false); 5200 if (!RDecl->hasTrivialCopyConstructor()) 5201 CXXRecord->setHasTrivialCopyConstructor(false); 5202 if (!RDecl->hasTrivialCopyAssignment()) 5203 CXXRecord->setHasTrivialCopyAssignment(false); 5204 if (!RDecl->hasTrivialDestructor()) 5205 CXXRecord->setHasTrivialDestructor(false); 5206 5207 // C++ 9.5p1: An object of a class with a non-trivial 5208 // constructor, a non-trivial copy constructor, a non-trivial 5209 // destructor, or a non-trivial copy assignment operator 5210 // cannot be a member of a union, nor can an array of such 5211 // objects. 5212 // TODO: C++0x alters this restriction significantly. 5213 if (Record->isUnion()) { 5214 // We check for copy constructors before constructors 5215 // because otherwise we'll never get complaints about 5216 // copy constructors. 5217 5218 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5219 5220 CXXSpecialMember member; 5221 if (!RDecl->hasTrivialCopyConstructor()) 5222 member = CXXCopyConstructor; 5223 else if (!RDecl->hasTrivialConstructor()) 5224 member = CXXDefaultConstructor; 5225 else if (!RDecl->hasTrivialCopyAssignment()) 5226 member = CXXCopyAssignment; 5227 else if (!RDecl->hasTrivialDestructor()) 5228 member = CXXDestructor; 5229 else 5230 member = invalid; 5231 5232 if (member != invalid) { 5233 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5234 DiagnoseNontrivial(RT, member); 5235 NewFD->setInvalidDecl(); 5236 } 5237 } 5238 } 5239 } 5240 5241 // FIXME: We need to pass in the attributes given an AST 5242 // representation, not a parser representation. 5243 if (D) 5244 // FIXME: What to pass instead of TUScope? 5245 ProcessDeclAttributes(TUScope, NewFD, *D); 5246 5247 if (T.isObjCGCWeak()) 5248 Diag(Loc, diag::warn_attribute_weak_on_field); 5249 5250 NewFD->setAccess(AS); 5251 5252 // C++ [dcl.init.aggr]p1: 5253 // An aggregate is an array or a class (clause 9) with [...] no 5254 // private or protected non-static data members (clause 11). 5255 // A POD must be an aggregate. 5256 if (getLangOptions().CPlusPlus && 5257 (AS == AS_private || AS == AS_protected)) { 5258 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5259 CXXRecord->setAggregate(false); 5260 CXXRecord->setPOD(false); 5261 } 5262 5263 return NewFD; 5264} 5265 5266/// DiagnoseNontrivial - Given that a class has a non-trivial 5267/// special member, figure out why. 5268void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5269 QualType QT(T, 0U); 5270 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5271 5272 // Check whether the member was user-declared. 5273 switch (member) { 5274 case CXXDefaultConstructor: 5275 if (RD->hasUserDeclaredConstructor()) { 5276 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5277 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5278 const FunctionDecl *body = 0; 5279 ci->getBody(body); 5280 if (!body || 5281 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5282 SourceLocation CtorLoc = ci->getLocation(); 5283 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5284 return; 5285 } 5286 } 5287 5288 assert(0 && "found no user-declared constructors"); 5289 return; 5290 } 5291 break; 5292 5293 case CXXCopyConstructor: 5294 if (RD->hasUserDeclaredCopyConstructor()) { 5295 SourceLocation CtorLoc = 5296 RD->getCopyConstructor(Context, 0)->getLocation(); 5297 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5298 return; 5299 } 5300 break; 5301 5302 case CXXCopyAssignment: 5303 if (RD->hasUserDeclaredCopyAssignment()) { 5304 // FIXME: this should use the location of the copy 5305 // assignment, not the type. 5306 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5307 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5308 return; 5309 } 5310 break; 5311 5312 case CXXDestructor: 5313 if (RD->hasUserDeclaredDestructor()) { 5314 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5315 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5316 return; 5317 } 5318 break; 5319 } 5320 5321 typedef CXXRecordDecl::base_class_iterator base_iter; 5322 5323 // Virtual bases and members inhibit trivial copying/construction, 5324 // but not trivial destruction. 5325 if (member != CXXDestructor) { 5326 // Check for virtual bases. vbases includes indirect virtual bases, 5327 // so we just iterate through the direct bases. 5328 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5329 if (bi->isVirtual()) { 5330 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5331 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5332 return; 5333 } 5334 5335 // Check for virtual methods. 5336 typedef CXXRecordDecl::method_iterator meth_iter; 5337 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5338 ++mi) { 5339 if (mi->isVirtual()) { 5340 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5341 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5342 return; 5343 } 5344 } 5345 } 5346 5347 bool (CXXRecordDecl::*hasTrivial)() const; 5348 switch (member) { 5349 case CXXDefaultConstructor: 5350 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5351 case CXXCopyConstructor: 5352 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5353 case CXXCopyAssignment: 5354 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5355 case CXXDestructor: 5356 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5357 default: 5358 assert(0 && "unexpected special member"); return; 5359 } 5360 5361 // Check for nontrivial bases (and recurse). 5362 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5363 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5364 assert(BaseRT && "Don't know how to handle dependent bases"); 5365 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5366 if (!(BaseRecTy->*hasTrivial)()) { 5367 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5368 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5369 DiagnoseNontrivial(BaseRT, member); 5370 return; 5371 } 5372 } 5373 5374 // Check for nontrivial members (and recurse). 5375 typedef RecordDecl::field_iterator field_iter; 5376 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5377 ++fi) { 5378 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5379 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5380 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5381 5382 if (!(EltRD->*hasTrivial)()) { 5383 SourceLocation FLoc = (*fi)->getLocation(); 5384 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5385 DiagnoseNontrivial(EltRT, member); 5386 return; 5387 } 5388 } 5389 } 5390 5391 assert(0 && "found no explanation for non-trivial member"); 5392} 5393 5394/// TranslateIvarVisibility - Translate visibility from a token ID to an 5395/// AST enum value. 5396static ObjCIvarDecl::AccessControl 5397TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5398 switch (ivarVisibility) { 5399 default: assert(0 && "Unknown visitibility kind"); 5400 case tok::objc_private: return ObjCIvarDecl::Private; 5401 case tok::objc_public: return ObjCIvarDecl::Public; 5402 case tok::objc_protected: return ObjCIvarDecl::Protected; 5403 case tok::objc_package: return ObjCIvarDecl::Package; 5404 } 5405} 5406 5407/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5408/// in order to create an IvarDecl object for it. 5409Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5410 SourceLocation DeclStart, 5411 DeclPtrTy IntfDecl, 5412 Declarator &D, ExprTy *BitfieldWidth, 5413 tok::ObjCKeywordKind Visibility) { 5414 5415 IdentifierInfo *II = D.getIdentifier(); 5416 Expr *BitWidth = (Expr*)BitfieldWidth; 5417 SourceLocation Loc = DeclStart; 5418 if (II) Loc = D.getIdentifierLoc(); 5419 5420 // FIXME: Unnamed fields can be handled in various different ways, for 5421 // example, unnamed unions inject all members into the struct namespace! 5422 5423 TypeSourceInfo *TInfo = 0; 5424 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5425 5426 if (BitWidth) { 5427 // 6.7.2.1p3, 6.7.2.1p4 5428 if (VerifyBitField(Loc, II, T, BitWidth)) { 5429 D.setInvalidType(); 5430 DeleteExpr(BitWidth); 5431 BitWidth = 0; 5432 } 5433 } else { 5434 // Not a bitfield. 5435 5436 // validate II. 5437 5438 } 5439 5440 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5441 // than a variably modified type. 5442 if (T->isVariablyModifiedType()) { 5443 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5444 D.setInvalidType(); 5445 } 5446 5447 // Get the visibility (access control) for this ivar. 5448 ObjCIvarDecl::AccessControl ac = 5449 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5450 : ObjCIvarDecl::None; 5451 // Must set ivar's DeclContext to its enclosing interface. 5452 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5453 DeclContext *EnclosingContext; 5454 if (ObjCImplementationDecl *IMPDecl = 5455 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5456 // Case of ivar declared in an implementation. Context is that of its class. 5457 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5458 assert(IDecl && "No class- ActOnIvar"); 5459 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5460 } else 5461 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5462 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5463 5464 // Construct the decl. 5465 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5466 EnclosingContext, Loc, II, T, 5467 TInfo, ac, (Expr *)BitfieldWidth); 5468 5469 if (II) { 5470 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5471 ForRedeclaration); 5472 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5473 && !isa<TagDecl>(PrevDecl)) { 5474 Diag(Loc, diag::err_duplicate_member) << II; 5475 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5476 NewID->setInvalidDecl(); 5477 } 5478 } 5479 5480 // Process attributes attached to the ivar. 5481 ProcessDeclAttributes(S, NewID, D); 5482 5483 if (D.isInvalidType()) 5484 NewID->setInvalidDecl(); 5485 5486 if (II) { 5487 // FIXME: When interfaces are DeclContexts, we'll need to add 5488 // these to the interface. 5489 S->AddDecl(DeclPtrTy::make(NewID)); 5490 IdResolver.AddDecl(NewID); 5491 } 5492 5493 return DeclPtrTy::make(NewID); 5494} 5495 5496void Sema::ActOnFields(Scope* S, 5497 SourceLocation RecLoc, DeclPtrTy RecDecl, 5498 DeclPtrTy *Fields, unsigned NumFields, 5499 SourceLocation LBrac, SourceLocation RBrac, 5500 AttributeList *Attr) { 5501 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5502 assert(EnclosingDecl && "missing record or interface decl"); 5503 5504 // If the decl this is being inserted into is invalid, then it may be a 5505 // redeclaration or some other bogus case. Don't try to add fields to it. 5506 if (EnclosingDecl->isInvalidDecl()) { 5507 // FIXME: Deallocate fields? 5508 return; 5509 } 5510 5511 5512 // Verify that all the fields are okay. 5513 unsigned NumNamedMembers = 0; 5514 llvm::SmallVector<FieldDecl*, 32> RecFields; 5515 5516 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5517 for (unsigned i = 0; i != NumFields; ++i) { 5518 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5519 5520 // Get the type for the field. 5521 Type *FDTy = FD->getType().getTypePtr(); 5522 5523 if (!FD->isAnonymousStructOrUnion()) { 5524 // Remember all fields written by the user. 5525 RecFields.push_back(FD); 5526 } 5527 5528 // If the field is already invalid for some reason, don't emit more 5529 // diagnostics about it. 5530 if (FD->isInvalidDecl()) { 5531 EnclosingDecl->setInvalidDecl(); 5532 continue; 5533 } 5534 5535 // C99 6.7.2.1p2: 5536 // A structure or union shall not contain a member with 5537 // incomplete or function type (hence, a structure shall not 5538 // contain an instance of itself, but may contain a pointer to 5539 // an instance of itself), except that the last member of a 5540 // structure with more than one named member may have incomplete 5541 // array type; such a structure (and any union containing, 5542 // possibly recursively, a member that is such a structure) 5543 // shall not be a member of a structure or an element of an 5544 // array. 5545 if (FDTy->isFunctionType()) { 5546 // Field declared as a function. 5547 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5548 << FD->getDeclName(); 5549 FD->setInvalidDecl(); 5550 EnclosingDecl->setInvalidDecl(); 5551 continue; 5552 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5553 Record && Record->isStruct()) { 5554 // Flexible array member. 5555 if (NumNamedMembers < 1) { 5556 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5557 << FD->getDeclName(); 5558 FD->setInvalidDecl(); 5559 EnclosingDecl->setInvalidDecl(); 5560 continue; 5561 } 5562 // Okay, we have a legal flexible array member at the end of the struct. 5563 if (Record) 5564 Record->setHasFlexibleArrayMember(true); 5565 } else if (!FDTy->isDependentType() && 5566 RequireCompleteType(FD->getLocation(), FD->getType(), 5567 diag::err_field_incomplete)) { 5568 // Incomplete type 5569 FD->setInvalidDecl(); 5570 EnclosingDecl->setInvalidDecl(); 5571 continue; 5572 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5573 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5574 // If this is a member of a union, then entire union becomes "flexible". 5575 if (Record && Record->isUnion()) { 5576 Record->setHasFlexibleArrayMember(true); 5577 } else { 5578 // If this is a struct/class and this is not the last element, reject 5579 // it. Note that GCC supports variable sized arrays in the middle of 5580 // structures. 5581 if (i != NumFields-1) 5582 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5583 << FD->getDeclName() << FD->getType(); 5584 else { 5585 // We support flexible arrays at the end of structs in 5586 // other structs as an extension. 5587 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5588 << FD->getDeclName(); 5589 if (Record) 5590 Record->setHasFlexibleArrayMember(true); 5591 } 5592 } 5593 } 5594 if (Record && FDTTy->getDecl()->hasObjectMember()) 5595 Record->setHasObjectMember(true); 5596 } else if (FDTy->isObjCInterfaceType()) { 5597 /// A field cannot be an Objective-c object 5598 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5599 FD->setInvalidDecl(); 5600 EnclosingDecl->setInvalidDecl(); 5601 continue; 5602 } else if (getLangOptions().ObjC1 && 5603 getLangOptions().getGCMode() != LangOptions::NonGC && 5604 Record && 5605 (FD->getType()->isObjCObjectPointerType() || 5606 FD->getType().isObjCGCStrong())) 5607 Record->setHasObjectMember(true); 5608 // Keep track of the number of named members. 5609 if (FD->getIdentifier()) 5610 ++NumNamedMembers; 5611 } 5612 5613 // Okay, we successfully defined 'Record'. 5614 if (Record) { 5615 Record->completeDefinition(Context); 5616 } else { 5617 ObjCIvarDecl **ClsFields = 5618 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5619 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5620 ID->setIVarList(ClsFields, RecFields.size(), Context); 5621 ID->setLocEnd(RBrac); 5622 // Add ivar's to class's DeclContext. 5623 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5624 ClsFields[i]->setLexicalDeclContext(ID); 5625 ID->addDecl(ClsFields[i]); 5626 } 5627 // Must enforce the rule that ivars in the base classes may not be 5628 // duplicates. 5629 if (ID->getSuperClass()) { 5630 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5631 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5632 ObjCIvarDecl* Ivar = (*IVI); 5633 5634 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5635 ObjCIvarDecl* prevIvar = 5636 ID->getSuperClass()->lookupInstanceVariable(II); 5637 if (prevIvar) { 5638 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5639 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5640 } 5641 } 5642 } 5643 } 5644 } else if (ObjCImplementationDecl *IMPDecl = 5645 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5646 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5647 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5648 // Ivar declared in @implementation never belongs to the implementation. 5649 // Only it is in implementation's lexical context. 5650 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5651 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5652 } 5653 } 5654 5655 if (Attr) 5656 ProcessDeclAttributeList(S, Record, Attr); 5657} 5658 5659EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5660 EnumConstantDecl *LastEnumConst, 5661 SourceLocation IdLoc, 5662 IdentifierInfo *Id, 5663 ExprArg val) { 5664 Expr *Val = (Expr *)val.get(); 5665 5666 llvm::APSInt EnumVal(32); 5667 QualType EltTy; 5668 if (Val) { 5669 if (Enum->isDependentType()) 5670 EltTy = Context.DependentTy; 5671 else { 5672 // Make sure to promote the operand type to int. 5673 UsualUnaryConversions(Val); 5674 if (Val != val.get()) { 5675 val.release(); 5676 val = Val; 5677 } 5678 5679 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5680 SourceLocation ExpLoc; 5681 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 5682 Val = 0; 5683 } else { 5684 EltTy = Val->getType(); 5685 } 5686 } 5687 } 5688 5689 if (!Val) { 5690 if (Enum->isDependentType()) 5691 EltTy = Context.DependentTy; 5692 else if (LastEnumConst) { 5693 // Assign the last value + 1. 5694 EnumVal = LastEnumConst->getInitVal(); 5695 ++EnumVal; 5696 5697 // Check for overflow on increment. 5698 if (EnumVal < LastEnumConst->getInitVal()) 5699 Diag(IdLoc, diag::warn_enum_value_overflow); 5700 5701 EltTy = LastEnumConst->getType(); 5702 } else { 5703 // First value, set to zero. 5704 EltTy = Context.IntTy; 5705 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5706 EnumVal.setIsSigned(true); 5707 } 5708 } 5709 5710 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5711 5712 val.release(); 5713 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5714 Val, EnumVal); 5715} 5716 5717 5718Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5719 DeclPtrTy lastEnumConst, 5720 SourceLocation IdLoc, 5721 IdentifierInfo *Id, 5722 SourceLocation EqualLoc, ExprTy *val) { 5723 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5724 EnumConstantDecl *LastEnumConst = 5725 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5726 Expr *Val = static_cast<Expr*>(val); 5727 5728 // The scope passed in may not be a decl scope. Zip up the scope tree until 5729 // we find one that is. 5730 S = getNonFieldDeclScope(S); 5731 5732 // Verify that there isn't already something declared with this name in this 5733 // scope. 5734 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5735 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5736 // Maybe we will complain about the shadowed template parameter. 5737 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5738 // Just pretend that we didn't see the previous declaration. 5739 PrevDecl = 0; 5740 } 5741 5742 if (PrevDecl) { 5743 // When in C++, we may get a TagDecl with the same name; in this case the 5744 // enum constant will 'hide' the tag. 5745 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5746 "Received TagDecl when not in C++!"); 5747 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5748 if (isa<EnumConstantDecl>(PrevDecl)) 5749 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5750 else 5751 Diag(IdLoc, diag::err_redefinition) << Id; 5752 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5753 if (Val) Val->Destroy(Context); 5754 return DeclPtrTy(); 5755 } 5756 } 5757 5758 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5759 IdLoc, Id, Owned(Val)); 5760 5761 // Register this decl in the current scope stack. 5762 if (New) 5763 PushOnScopeChains(New, S); 5764 5765 return DeclPtrTy::make(New); 5766} 5767 5768void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5769 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5770 DeclPtrTy *Elements, unsigned NumElements, 5771 Scope *S, AttributeList *Attr) { 5772 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5773 QualType EnumType = Context.getTypeDeclType(Enum); 5774 5775 if (Attr) 5776 ProcessDeclAttributeList(S, Enum, Attr); 5777 5778 if (Enum->isDependentType()) { 5779 for (unsigned i = 0; i != NumElements; ++i) { 5780 EnumConstantDecl *ECD = 5781 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5782 if (!ECD) continue; 5783 5784 ECD->setType(EnumType); 5785 } 5786 5787 Enum->completeDefinition(Context, Context.DependentTy, Context.DependentTy); 5788 return; 5789 } 5790 5791 // TODO: If the result value doesn't fit in an int, it must be a long or long 5792 // long value. ISO C does not support this, but GCC does as an extension, 5793 // emit a warning. 5794 unsigned IntWidth = Context.Target.getIntWidth(); 5795 unsigned CharWidth = Context.Target.getCharWidth(); 5796 unsigned ShortWidth = Context.Target.getShortWidth(); 5797 5798 // Verify that all the values are okay, compute the size of the values, and 5799 // reverse the list. 5800 unsigned NumNegativeBits = 0; 5801 unsigned NumPositiveBits = 0; 5802 5803 // Keep track of whether all elements have type int. 5804 bool AllElementsInt = true; 5805 5806 for (unsigned i = 0; i != NumElements; ++i) { 5807 EnumConstantDecl *ECD = 5808 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5809 if (!ECD) continue; // Already issued a diagnostic. 5810 5811 // If the enum value doesn't fit in an int, emit an extension warning. 5812 const llvm::APSInt &InitVal = ECD->getInitVal(); 5813 assert(InitVal.getBitWidth() >= IntWidth && 5814 "Should have promoted value to int"); 5815 if (!getLangOptions().CPlusPlus && InitVal.getBitWidth() > IntWidth) { 5816 llvm::APSInt V(InitVal); 5817 V.trunc(IntWidth); 5818 V.extend(InitVal.getBitWidth()); 5819 if (V != InitVal) 5820 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5821 << InitVal.toString(10); 5822 } 5823 5824 // Keep track of the size of positive and negative values. 5825 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5826 NumPositiveBits = std::max(NumPositiveBits, 5827 (unsigned)InitVal.getActiveBits()); 5828 else 5829 NumNegativeBits = std::max(NumNegativeBits, 5830 (unsigned)InitVal.getMinSignedBits()); 5831 5832 // Keep track of whether every enum element has type int (very commmon). 5833 if (AllElementsInt) 5834 AllElementsInt = ECD->getType() == Context.IntTy; 5835 } 5836 5837 // Figure out the type that should be used for this enum. 5838 // FIXME: Support -fshort-enums. 5839 QualType BestType; 5840 unsigned BestWidth; 5841 5842 // C++0x N3000 [conv.prom]p3: 5843 // An rvalue of an unscoped enumeration type whose underlying 5844 // type is not fixed can be converted to an rvalue of the first 5845 // of the following types that can represent all the values of 5846 // the enumeration: int, unsigned int, long int, unsigned long 5847 // int, long long int, or unsigned long long int. 5848 // C99 6.4.4.3p2: 5849 // An identifier declared as an enumeration constant has type int. 5850 // The C99 rule is modified by a gcc extension 5851 QualType BestPromotionType; 5852 5853 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5854 5855 if (NumNegativeBits) { 5856 // If there is a negative value, figure out the smallest integer type (of 5857 // int/long/longlong) that fits. 5858 // If it's packed, check also if it fits a char or a short. 5859 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5860 BestType = Context.SignedCharTy; 5861 BestWidth = CharWidth; 5862 } else if (Packed && NumNegativeBits <= ShortWidth && 5863 NumPositiveBits < ShortWidth) { 5864 BestType = Context.ShortTy; 5865 BestWidth = ShortWidth; 5866 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5867 BestType = Context.IntTy; 5868 BestWidth = IntWidth; 5869 } else { 5870 BestWidth = Context.Target.getLongWidth(); 5871 5872 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5873 BestType = Context.LongTy; 5874 } else { 5875 BestWidth = Context.Target.getLongLongWidth(); 5876 5877 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5878 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5879 BestType = Context.LongLongTy; 5880 } 5881 } 5882 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5883 } else { 5884 // If there is no negative value, figure out which of uint, ulong, ulonglong 5885 // fits. 5886 // If it's packed, check also if it fits a char or a short. 5887 if (Packed && NumPositiveBits <= CharWidth) { 5888 BestType = Context.UnsignedCharTy; 5889 BestPromotionType = Context.IntTy; 5890 BestWidth = CharWidth; 5891 } else if (Packed && NumPositiveBits <= ShortWidth) { 5892 BestType = Context.UnsignedShortTy; 5893 BestPromotionType = Context.IntTy; 5894 BestWidth = ShortWidth; 5895 } else if (NumPositiveBits <= IntWidth) { 5896 BestType = Context.UnsignedIntTy; 5897 BestWidth = IntWidth; 5898 BestPromotionType = (NumPositiveBits == BestWidth 5899 ? Context.UnsignedIntTy : Context.IntTy); 5900 } else if (NumPositiveBits <= 5901 (BestWidth = Context.Target.getLongWidth())) { 5902 BestType = Context.UnsignedLongTy; 5903 BestPromotionType = (NumPositiveBits == BestWidth 5904 ? Context.UnsignedLongTy : Context.LongTy); 5905 } else { 5906 BestWidth = Context.Target.getLongLongWidth(); 5907 assert(NumPositiveBits <= BestWidth && 5908 "How could an initializer get larger than ULL?"); 5909 BestType = Context.UnsignedLongLongTy; 5910 BestPromotionType = (NumPositiveBits == BestWidth 5911 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5912 } 5913 } 5914 5915 // If we're in C and the promotion type is larger than an int, just 5916 // use the underlying type, which is generally the unsigned integer 5917 // type of the same rank as the promotion type. This is how the gcc 5918 // extension works. 5919 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5920 BestPromotionType = BestType; 5921 5922 // Loop over all of the enumerator constants, changing their types to match 5923 // the type of the enum if needed. 5924 for (unsigned i = 0; i != NumElements; ++i) { 5925 EnumConstantDecl *ECD = 5926 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5927 if (!ECD) continue; // Already issued a diagnostic. 5928 5929 // Standard C says the enumerators have int type, but we allow, as an 5930 // extension, the enumerators to be larger than int size. If each 5931 // enumerator value fits in an int, type it as an int, otherwise type it the 5932 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5933 // that X has type 'int', not 'unsigned'. 5934 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 5935 continue; 5936 5937 // Determine whether the value fits into an int. 5938 llvm::APSInt InitVal = ECD->getInitVal(); 5939 bool FitsInInt; 5940 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5941 FitsInInt = InitVal.getActiveBits() < IntWidth; 5942 else 5943 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5944 5945 // If it fits into an integer type, force it. Otherwise force it to match 5946 // the enum decl type. 5947 QualType NewTy; 5948 unsigned NewWidth; 5949 bool NewSign; 5950 if (FitsInInt && !getLangOptions().CPlusPlus) { 5951 NewTy = Context.IntTy; 5952 NewWidth = IntWidth; 5953 NewSign = true; 5954 } else if (ECD->getType() == BestType) { 5955 // Already the right type! 5956 if (getLangOptions().CPlusPlus) 5957 // C++ [dcl.enum]p4: Following the closing brace of an 5958 // enum-specifier, each enumerator has the type of its 5959 // enumeration. 5960 ECD->setType(EnumType); 5961 continue; 5962 } else { 5963 NewTy = BestType; 5964 NewWidth = BestWidth; 5965 NewSign = BestType->isSignedIntegerType(); 5966 } 5967 5968 // Adjust the APSInt value. 5969 InitVal.extOrTrunc(NewWidth); 5970 InitVal.setIsSigned(NewSign); 5971 ECD->setInitVal(InitVal); 5972 5973 // Adjust the Expr initializer and type. 5974 if (ECD->getInitExpr()) 5975 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5976 CastExpr::CK_IntegralCast, 5977 ECD->getInitExpr(), 5978 /*isLvalue=*/false)); 5979 if (getLangOptions().CPlusPlus) 5980 // C++ [dcl.enum]p4: Following the closing brace of an 5981 // enum-specifier, each enumerator has the type of its 5982 // enumeration. 5983 ECD->setType(EnumType); 5984 else 5985 ECD->setType(NewTy); 5986 } 5987 5988 Enum->completeDefinition(Context, BestType, BestPromotionType); 5989} 5990 5991Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5992 ExprArg expr) { 5993 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5994 5995 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5996 Loc, AsmString); 5997 CurContext->addDecl(New); 5998 return DeclPtrTy::make(New); 5999} 6000 6001void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 6002 SourceLocation PragmaLoc, 6003 SourceLocation NameLoc) { 6004 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 6005 6006 if (PrevDecl) { 6007 PrevDecl->addAttr(::new (Context) WeakAttr()); 6008 } else { 6009 (void)WeakUndeclaredIdentifiers.insert( 6010 std::pair<IdentifierInfo*,WeakInfo> 6011 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 6012 } 6013} 6014 6015void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 6016 IdentifierInfo* AliasName, 6017 SourceLocation PragmaLoc, 6018 SourceLocation NameLoc, 6019 SourceLocation AliasNameLoc) { 6020 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6021 WeakInfo W = WeakInfo(Name, NameLoc); 6022 6023 if (PrevDecl) { 6024 if (!PrevDecl->hasAttr<AliasAttr>()) 6025 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6026 DeclApplyPragmaWeak(TUScope, ND, W); 6027 } else { 6028 (void)WeakUndeclaredIdentifiers.insert( 6029 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6030 } 6031} 6032