SemaDecl.cpp revision 9f54ad4381370c6b771424b53d219e661d6d6706
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 Diag(New->getLocation(), diag::err_redefinition_different_kind) 807 << New->getDeclName(); 808 Diag(OldD->getLocation(), diag::note_previous_definition); 809 return true; 810 } 811 812 // Determine whether the previous declaration was a definition, 813 // implicit declaration, or a declaration. 814 diag::kind PrevDiag; 815 if (Old->isThisDeclarationADefinition()) 816 PrevDiag = diag::note_previous_definition; 817 else if (Old->isImplicit()) 818 PrevDiag = diag::note_previous_implicit_declaration; 819 else 820 PrevDiag = diag::note_previous_declaration; 821 822 QualType OldQType = Context.getCanonicalType(Old->getType()); 823 QualType NewQType = Context.getCanonicalType(New->getType()); 824 825 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 826 New->getStorageClass() == FunctionDecl::Static && 827 Old->getStorageClass() != FunctionDecl::Static) { 828 Diag(New->getLocation(), diag::err_static_non_static) 829 << New; 830 Diag(Old->getLocation(), PrevDiag); 831 return true; 832 } 833 834 if (getLangOptions().CPlusPlus) { 835 // (C++98 13.1p2): 836 // Certain function declarations cannot be overloaded: 837 // -- Function declarations that differ only in the return type 838 // cannot be overloaded. 839 QualType OldReturnType 840 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 841 QualType NewReturnType 842 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 843 if (OldReturnType != NewReturnType) { 844 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 845 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 846 return true; 847 } 848 849 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 850 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 851 if (OldMethod && NewMethod) { 852 if (!NewMethod->getFriendObjectKind() && 853 NewMethod->getLexicalDeclContext()->isRecord()) { 854 // -- Member function declarations with the same name and the 855 // same parameter types cannot be overloaded if any of them 856 // is a static member function declaration. 857 if (OldMethod->isStatic() || NewMethod->isStatic()) { 858 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 859 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 860 return true; 861 } 862 863 // C++ [class.mem]p1: 864 // [...] A member shall not be declared twice in the 865 // member-specification, except that a nested class or member 866 // class template can be declared and then later defined. 867 unsigned NewDiag; 868 if (isa<CXXConstructorDecl>(OldMethod)) 869 NewDiag = diag::err_constructor_redeclared; 870 else if (isa<CXXDestructorDecl>(NewMethod)) 871 NewDiag = diag::err_destructor_redeclared; 872 else if (isa<CXXConversionDecl>(NewMethod)) 873 NewDiag = diag::err_conv_function_redeclared; 874 else 875 NewDiag = diag::err_member_redeclared; 876 877 Diag(New->getLocation(), NewDiag); 878 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 879 } else { 880 if (OldMethod->isImplicit()) { 881 Diag(NewMethod->getLocation(), 882 diag::err_definition_of_implicitly_declared_member) 883 << New << getSpecialMember(Context, OldMethod); 884 885 Diag(OldMethod->getLocation(), 886 diag::note_previous_implicit_declaration); 887 return true; 888 } 889 } 890 } 891 892 // (C++98 8.3.5p3): 893 // All declarations for a function shall agree exactly in both the 894 // return type and the parameter-type-list. 895 if (OldQType == NewQType) 896 return MergeCompatibleFunctionDecls(New, Old); 897 898 // Fall through for conflicting redeclarations and redefinitions. 899 } 900 901 // C: Function types need to be compatible, not identical. This handles 902 // duplicate function decls like "void f(int); void f(enum X);" properly. 903 if (!getLangOptions().CPlusPlus && 904 Context.typesAreCompatible(OldQType, NewQType)) { 905 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 906 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 907 const FunctionProtoType *OldProto = 0; 908 if (isa<FunctionNoProtoType>(NewFuncType) && 909 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 910 // The old declaration provided a function prototype, but the 911 // new declaration does not. Merge in the prototype. 912 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 913 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 914 OldProto->arg_type_end()); 915 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 916 ParamTypes.data(), ParamTypes.size(), 917 OldProto->isVariadic(), 918 OldProto->getTypeQuals()); 919 New->setType(NewQType); 920 New->setHasInheritedPrototype(); 921 922 // Synthesize a parameter for each argument type. 923 llvm::SmallVector<ParmVarDecl*, 16> Params; 924 for (FunctionProtoType::arg_type_iterator 925 ParamType = OldProto->arg_type_begin(), 926 ParamEnd = OldProto->arg_type_end(); 927 ParamType != ParamEnd; ++ParamType) { 928 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 929 SourceLocation(), 0, 930 *ParamType, /*TInfo=*/0, 931 VarDecl::None, 0); 932 Param->setImplicit(); 933 Params.push_back(Param); 934 } 935 936 New->setParams(Context, Params.data(), Params.size()); 937 } 938 939 return MergeCompatibleFunctionDecls(New, Old); 940 } 941 942 // GNU C permits a K&R definition to follow a prototype declaration 943 // if the declared types of the parameters in the K&R definition 944 // match the types in the prototype declaration, even when the 945 // promoted types of the parameters from the K&R definition differ 946 // from the types in the prototype. GCC then keeps the types from 947 // the prototype. 948 // 949 // If a variadic prototype is followed by a non-variadic K&R definition, 950 // the K&R definition becomes variadic. This is sort of an edge case, but 951 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 952 // C99 6.9.1p8. 953 if (!getLangOptions().CPlusPlus && 954 Old->hasPrototype() && !New->hasPrototype() && 955 New->getType()->getAs<FunctionProtoType>() && 956 Old->getNumParams() == New->getNumParams()) { 957 llvm::SmallVector<QualType, 16> ArgTypes; 958 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 959 const FunctionProtoType *OldProto 960 = Old->getType()->getAs<FunctionProtoType>(); 961 const FunctionProtoType *NewProto 962 = New->getType()->getAs<FunctionProtoType>(); 963 964 // Determine whether this is the GNU C extension. 965 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 966 NewProto->getResultType()); 967 bool LooseCompatible = !MergedReturn.isNull(); 968 for (unsigned Idx = 0, End = Old->getNumParams(); 969 LooseCompatible && Idx != End; ++Idx) { 970 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 971 ParmVarDecl *NewParm = New->getParamDecl(Idx); 972 if (Context.typesAreCompatible(OldParm->getType(), 973 NewProto->getArgType(Idx))) { 974 ArgTypes.push_back(NewParm->getType()); 975 } else if (Context.typesAreCompatible(OldParm->getType(), 976 NewParm->getType())) { 977 GNUCompatibleParamWarning Warn 978 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 979 Warnings.push_back(Warn); 980 ArgTypes.push_back(NewParm->getType()); 981 } else 982 LooseCompatible = false; 983 } 984 985 if (LooseCompatible) { 986 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 987 Diag(Warnings[Warn].NewParm->getLocation(), 988 diag::ext_param_promoted_not_compatible_with_prototype) 989 << Warnings[Warn].PromotedType 990 << Warnings[Warn].OldParm->getType(); 991 Diag(Warnings[Warn].OldParm->getLocation(), 992 diag::note_previous_declaration); 993 } 994 995 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 996 ArgTypes.size(), 997 OldProto->isVariadic(), 0)); 998 return MergeCompatibleFunctionDecls(New, Old); 999 } 1000 1001 // Fall through to diagnose conflicting types. 1002 } 1003 1004 // A function that has already been declared has been redeclared or defined 1005 // with a different type- show appropriate diagnostic 1006 if (unsigned BuiltinID = Old->getBuiltinID()) { 1007 // The user has declared a builtin function with an incompatible 1008 // signature. 1009 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1010 // The function the user is redeclaring is a library-defined 1011 // function like 'malloc' or 'printf'. Warn about the 1012 // redeclaration, then pretend that we don't know about this 1013 // library built-in. 1014 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1015 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1016 << Old << Old->getType(); 1017 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1018 Old->setInvalidDecl(); 1019 return false; 1020 } 1021 1022 PrevDiag = diag::note_previous_builtin_declaration; 1023 } 1024 1025 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1026 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1027 return true; 1028} 1029 1030/// \brief Completes the merge of two function declarations that are 1031/// known to be compatible. 1032/// 1033/// This routine handles the merging of attributes and other 1034/// properties of function declarations form the old declaration to 1035/// the new declaration, once we know that New is in fact a 1036/// redeclaration of Old. 1037/// 1038/// \returns false 1039bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1040 // Merge the attributes 1041 MergeAttributes(New, Old, Context); 1042 1043 // Merge the storage class. 1044 if (Old->getStorageClass() != FunctionDecl::Extern && 1045 Old->getStorageClass() != FunctionDecl::None) 1046 New->setStorageClass(Old->getStorageClass()); 1047 1048 // Merge "pure" flag. 1049 if (Old->isPure()) 1050 New->setPure(); 1051 1052 // Merge the "deleted" flag. 1053 if (Old->isDeleted()) 1054 New->setDeleted(); 1055 1056 if (getLangOptions().CPlusPlus) 1057 return MergeCXXFunctionDecl(New, Old); 1058 1059 return false; 1060} 1061 1062/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1063/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1064/// situation, merging decls or emitting diagnostics as appropriate. 1065/// 1066/// Tentative definition rules (C99 6.9.2p2) are checked by 1067/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1068/// definitions here, since the initializer hasn't been attached. 1069/// 1070void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1071 // If the new decl is already invalid, don't do any other checking. 1072 if (New->isInvalidDecl()) 1073 return; 1074 1075 // Verify the old decl was also a variable. 1076 VarDecl *Old = 0; 1077 if (!Previous.isSingleResult() || 1078 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1079 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1080 << New->getDeclName(); 1081 Diag(Previous.getRepresentativeDecl()->getLocation(), 1082 diag::note_previous_definition); 1083 return New->setInvalidDecl(); 1084 } 1085 1086 MergeAttributes(New, Old, Context); 1087 1088 // Merge the types 1089 QualType MergedT; 1090 if (getLangOptions().CPlusPlus) { 1091 if (Context.hasSameType(New->getType(), Old->getType())) 1092 MergedT = New->getType(); 1093 // C++ [basic.link]p10: 1094 // [...] the types specified by all declarations referring to a given 1095 // object or function shall be identical, except that declarations for an 1096 // array object can specify array types that differ by the presence or 1097 // absence of a major array bound (8.3.4). 1098 else if (Old->getType()->isIncompleteArrayType() && 1099 New->getType()->isArrayType()) { 1100 CanQual<ArrayType> OldArray 1101 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1102 CanQual<ArrayType> NewArray 1103 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1104 if (OldArray->getElementType() == NewArray->getElementType()) 1105 MergedT = New->getType(); 1106 } else if (Old->getType()->isArrayType() && 1107 New->getType()->isIncompleteArrayType()) { 1108 CanQual<ArrayType> OldArray 1109 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1110 CanQual<ArrayType> NewArray 1111 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1112 if (OldArray->getElementType() == NewArray->getElementType()) 1113 MergedT = Old->getType(); 1114 } 1115 } else { 1116 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1117 } 1118 if (MergedT.isNull()) { 1119 Diag(New->getLocation(), diag::err_redefinition_different_type) 1120 << New->getDeclName(); 1121 Diag(Old->getLocation(), diag::note_previous_definition); 1122 return New->setInvalidDecl(); 1123 } 1124 New->setType(MergedT); 1125 1126 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1127 if (New->getStorageClass() == VarDecl::Static && 1128 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1129 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1130 Diag(Old->getLocation(), diag::note_previous_definition); 1131 return New->setInvalidDecl(); 1132 } 1133 // C99 6.2.2p4: 1134 // For an identifier declared with the storage-class specifier 1135 // extern in a scope in which a prior declaration of that 1136 // identifier is visible,23) if the prior declaration specifies 1137 // internal or external linkage, the linkage of the identifier at 1138 // the later declaration is the same as the linkage specified at 1139 // the prior declaration. If no prior declaration is visible, or 1140 // if the prior declaration specifies no linkage, then the 1141 // identifier has external linkage. 1142 if (New->hasExternalStorage() && Old->hasLinkage()) 1143 /* Okay */; 1144 else if (New->getStorageClass() != VarDecl::Static && 1145 Old->getStorageClass() == VarDecl::Static) { 1146 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1147 Diag(Old->getLocation(), diag::note_previous_definition); 1148 return New->setInvalidDecl(); 1149 } 1150 1151 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1152 1153 // FIXME: The test for external storage here seems wrong? We still 1154 // need to check for mismatches. 1155 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1156 // Don't complain about out-of-line definitions of static members. 1157 !(Old->getLexicalDeclContext()->isRecord() && 1158 !New->getLexicalDeclContext()->isRecord())) { 1159 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1160 Diag(Old->getLocation(), diag::note_previous_definition); 1161 return New->setInvalidDecl(); 1162 } 1163 1164 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1165 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1166 Diag(Old->getLocation(), diag::note_previous_definition); 1167 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1168 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1169 Diag(Old->getLocation(), diag::note_previous_definition); 1170 } 1171 1172 // Keep a chain of previous declarations. 1173 New->setPreviousDeclaration(Old); 1174} 1175 1176/// CheckFallThrough - Check that we don't fall off the end of a 1177/// Statement that should return a value. 1178/// 1179/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1180/// MaybeFallThrough iff we might or might not fall off the end, 1181/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1182/// return. We assume NeverFallThrough iff we never fall off the end of the 1183/// statement but we may return. We assume that functions not marked noreturn 1184/// will return. 1185Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1186 // FIXME: Eventually share this CFG object when we have other warnings based 1187 // of the CFG. This can be done using AnalysisContext. 1188 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1189 1190 // FIXME: They should never return 0, fix that, delete this code. 1191 if (cfg == 0) 1192 // FIXME: This should be NeverFallThrough 1193 return NeverFallThroughOrReturn; 1194 // The CFG leaves in dead things, and we don't want to dead code paths to 1195 // confuse us, so we mark all live things first. 1196 std::queue<CFGBlock*> workq; 1197 llvm::BitVector live(cfg->getNumBlockIDs()); 1198 // Prep work queue 1199 workq.push(&cfg->getEntry()); 1200 // Solve 1201 while (!workq.empty()) { 1202 CFGBlock *item = workq.front(); 1203 workq.pop(); 1204 live.set(item->getBlockID()); 1205 for (CFGBlock::succ_iterator I=item->succ_begin(), 1206 E=item->succ_end(); 1207 I != E; 1208 ++I) { 1209 if ((*I) && !live[(*I)->getBlockID()]) { 1210 live.set((*I)->getBlockID()); 1211 workq.push(*I); 1212 } 1213 } 1214 } 1215 1216 // Now we know what is live, we check the live precessors of the exit block 1217 // and look for fall through paths, being careful to ignore normal returns, 1218 // and exceptional paths. 1219 bool HasLiveReturn = false; 1220 bool HasFakeEdge = false; 1221 bool HasPlainEdge = false; 1222 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1223 E = cfg->getExit().pred_end(); 1224 I != E; 1225 ++I) { 1226 CFGBlock& B = **I; 1227 if (!live[B.getBlockID()]) 1228 continue; 1229 if (B.size() == 0) { 1230 // A labeled empty statement, or the entry block... 1231 HasPlainEdge = true; 1232 continue; 1233 } 1234 Stmt *S = B[B.size()-1]; 1235 if (isa<ReturnStmt>(S)) { 1236 HasLiveReturn = true; 1237 continue; 1238 } 1239 if (isa<ObjCAtThrowStmt>(S)) { 1240 HasFakeEdge = true; 1241 continue; 1242 } 1243 if (isa<CXXThrowExpr>(S)) { 1244 HasFakeEdge = true; 1245 continue; 1246 } 1247 bool NoReturnEdge = false; 1248 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1249 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1250 if (CEE->getType().getNoReturnAttr()) { 1251 NoReturnEdge = true; 1252 HasFakeEdge = true; 1253 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1254 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1255 if (FD->hasAttr<NoReturnAttr>()) { 1256 NoReturnEdge = true; 1257 HasFakeEdge = true; 1258 } 1259 } 1260 } 1261 } 1262 // FIXME: Add noreturn message sends. 1263 if (NoReturnEdge == false) 1264 HasPlainEdge = true; 1265 } 1266 if (!HasPlainEdge) { 1267 if (HasLiveReturn) 1268 return NeverFallThrough; 1269 return NeverFallThroughOrReturn; 1270 } 1271 if (HasFakeEdge || HasLiveReturn) 1272 return MaybeFallThrough; 1273 // This says AlwaysFallThrough for calls to functions that are not marked 1274 // noreturn, that don't return. If people would like this warning to be more 1275 // accurate, such functions should be marked as noreturn. 1276 return AlwaysFallThrough; 1277} 1278 1279/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1280/// function that should return a value. Check that we don't fall off the end 1281/// of a noreturn function. We assume that functions and blocks not marked 1282/// noreturn will return. 1283void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1284 // FIXME: Would be nice if we had a better way to control cascading errors, 1285 // but for now, avoid them. The problem is that when Parse sees: 1286 // int foo() { return a; } 1287 // The return is eaten and the Sema code sees just: 1288 // int foo() { } 1289 // which this code would then warn about. 1290 if (getDiagnostics().hasErrorOccurred()) 1291 return; 1292 1293 bool ReturnsVoid = false; 1294 bool HasNoReturn = false; 1295 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1296 // If the result type of the function is a dependent type, we don't know 1297 // whether it will be void or not, so don't 1298 if (FD->getResultType()->isDependentType()) 1299 return; 1300 if (FD->getResultType()->isVoidType()) 1301 ReturnsVoid = true; 1302 if (FD->hasAttr<NoReturnAttr>()) 1303 HasNoReturn = true; 1304 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1305 if (MD->getResultType()->isVoidType()) 1306 ReturnsVoid = true; 1307 if (MD->hasAttr<NoReturnAttr>()) 1308 HasNoReturn = true; 1309 } 1310 1311 // Short circuit for compilation speed. 1312 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1313 == Diagnostic::Ignored || ReturnsVoid) 1314 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1315 == Diagnostic::Ignored || !HasNoReturn) 1316 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1317 == Diagnostic::Ignored || !ReturnsVoid)) 1318 return; 1319 // FIXME: Function try block 1320 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1321 switch (CheckFallThrough(Body)) { 1322 case MaybeFallThrough: 1323 if (HasNoReturn) 1324 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1325 else if (!ReturnsVoid) 1326 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1327 break; 1328 case AlwaysFallThrough: 1329 if (HasNoReturn) 1330 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1331 else if (!ReturnsVoid) 1332 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1333 break; 1334 case NeverFallThroughOrReturn: 1335 if (ReturnsVoid && !HasNoReturn) 1336 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1337 break; 1338 case NeverFallThrough: 1339 break; 1340 } 1341 } 1342} 1343 1344/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1345/// that should return a value. Check that we don't fall off the end of a 1346/// noreturn block. We assume that functions and blocks not marked noreturn 1347/// will return. 1348void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1349 // FIXME: Would be nice if we had a better way to control cascading errors, 1350 // but for now, avoid them. The problem is that when Parse sees: 1351 // int foo() { return a; } 1352 // The return is eaten and the Sema code sees just: 1353 // int foo() { } 1354 // which this code would then warn about. 1355 if (getDiagnostics().hasErrorOccurred()) 1356 return; 1357 bool ReturnsVoid = false; 1358 bool HasNoReturn = false; 1359 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1360 if (FT->getResultType()->isVoidType()) 1361 ReturnsVoid = true; 1362 if (FT->getNoReturnAttr()) 1363 HasNoReturn = true; 1364 } 1365 1366 // Short circuit for compilation speed. 1367 if (ReturnsVoid 1368 && !HasNoReturn 1369 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1370 == Diagnostic::Ignored || !ReturnsVoid)) 1371 return; 1372 // FIXME: Funtion try block 1373 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1374 switch (CheckFallThrough(Body)) { 1375 case MaybeFallThrough: 1376 if (HasNoReturn) 1377 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1378 else if (!ReturnsVoid) 1379 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1380 break; 1381 case AlwaysFallThrough: 1382 if (HasNoReturn) 1383 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1384 else if (!ReturnsVoid) 1385 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1386 break; 1387 case NeverFallThroughOrReturn: 1388 if (ReturnsVoid) 1389 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1390 break; 1391 case NeverFallThrough: 1392 break; 1393 } 1394 } 1395} 1396 1397/// CheckParmsForFunctionDef - Check that the parameters of the given 1398/// function are appropriate for the definition of a function. This 1399/// takes care of any checks that cannot be performed on the 1400/// declaration itself, e.g., that the types of each of the function 1401/// parameters are complete. 1402bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1403 bool HasInvalidParm = false; 1404 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1405 ParmVarDecl *Param = FD->getParamDecl(p); 1406 1407 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1408 // function declarator that is part of a function definition of 1409 // that function shall not have incomplete type. 1410 // 1411 // This is also C++ [dcl.fct]p6. 1412 if (!Param->isInvalidDecl() && 1413 RequireCompleteType(Param->getLocation(), Param->getType(), 1414 diag::err_typecheck_decl_incomplete_type)) { 1415 Param->setInvalidDecl(); 1416 HasInvalidParm = true; 1417 } 1418 1419 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1420 // declaration of each parameter shall include an identifier. 1421 if (Param->getIdentifier() == 0 && 1422 !Param->isImplicit() && 1423 !getLangOptions().CPlusPlus) 1424 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1425 } 1426 1427 return HasInvalidParm; 1428} 1429 1430/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1431/// no declarator (e.g. "struct foo;") is parsed. 1432Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1433 // FIXME: Error on auto/register at file scope 1434 // FIXME: Error on inline/virtual/explicit 1435 // FIXME: Error on invalid restrict 1436 // FIXME: Warn on useless __thread 1437 // FIXME: Warn on useless const/volatile 1438 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1439 // FIXME: Warn on useless attributes 1440 Decl *TagD = 0; 1441 TagDecl *Tag = 0; 1442 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1443 DS.getTypeSpecType() == DeclSpec::TST_struct || 1444 DS.getTypeSpecType() == DeclSpec::TST_union || 1445 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1446 TagD = static_cast<Decl *>(DS.getTypeRep()); 1447 1448 if (!TagD) // We probably had an error 1449 return DeclPtrTy(); 1450 1451 // Note that the above type specs guarantee that the 1452 // type rep is a Decl, whereas in many of the others 1453 // it's a Type. 1454 Tag = dyn_cast<TagDecl>(TagD); 1455 } 1456 1457 if (DS.isFriendSpecified()) { 1458 // If we're dealing with a class template decl, assume that the 1459 // template routines are handling it. 1460 if (TagD && isa<ClassTemplateDecl>(TagD)) 1461 return DeclPtrTy(); 1462 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1463 } 1464 1465 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1466 // If there are attributes in the DeclSpec, apply them to the record. 1467 if (const AttributeList *AL = DS.getAttributes()) 1468 ProcessDeclAttributeList(S, Record, AL); 1469 1470 if (!Record->getDeclName() && Record->isDefinition() && 1471 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1472 if (getLangOptions().CPlusPlus || 1473 Record->getDeclContext()->isRecord()) 1474 return BuildAnonymousStructOrUnion(S, DS, Record); 1475 1476 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1477 << DS.getSourceRange(); 1478 } 1479 1480 // Microsoft allows unnamed struct/union fields. Don't complain 1481 // about them. 1482 // FIXME: Should we support Microsoft's extensions in this area? 1483 if (Record->getDeclName() && getLangOptions().Microsoft) 1484 return DeclPtrTy::make(Tag); 1485 } 1486 1487 if (!DS.isMissingDeclaratorOk() && 1488 DS.getTypeSpecType() != DeclSpec::TST_error) { 1489 // Warn about typedefs of enums without names, since this is an 1490 // extension in both Microsoft an GNU. 1491 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1492 Tag && isa<EnumDecl>(Tag)) { 1493 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1494 << DS.getSourceRange(); 1495 return DeclPtrTy::make(Tag); 1496 } 1497 1498 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1499 << DS.getSourceRange(); 1500 return DeclPtrTy(); 1501 } 1502 1503 return DeclPtrTy::make(Tag); 1504} 1505 1506/// We are trying to introduce the given name into the given context; 1507/// check if there's an existing declaration that can't be overloaded. 1508/// 1509/// \return true if this is a forbidden redeclaration 1510bool Sema::CheckRedeclaration(DeclContext *DC, 1511 DeclarationName Name, 1512 SourceLocation NameLoc, 1513 unsigned diagnostic) { 1514 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName, 1515 ForRedeclaration); 1516 LookupQualifiedName(R, DC); 1517 1518 if (R.empty()) return false; 1519 1520 if (R.getResultKind() == LookupResult::Found && 1521 isa<TagDecl>(R.getFoundDecl())) 1522 return false; 1523 1524 // Pick a representative declaration. 1525 NamedDecl *PrevDecl = (*R.begin())->getUnderlyingDecl(); 1526 1527 Diag(NameLoc, diagnostic) << Name; 1528 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1529 1530 return true; 1531} 1532 1533/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1534/// anonymous struct or union AnonRecord into the owning context Owner 1535/// and scope S. This routine will be invoked just after we realize 1536/// that an unnamed union or struct is actually an anonymous union or 1537/// struct, e.g., 1538/// 1539/// @code 1540/// union { 1541/// int i; 1542/// float f; 1543/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1544/// // f into the surrounding scope.x 1545/// @endcode 1546/// 1547/// This routine is recursive, injecting the names of nested anonymous 1548/// structs/unions into the owning context and scope as well. 1549bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1550 RecordDecl *AnonRecord) { 1551 unsigned diagKind 1552 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1553 : diag::err_anonymous_struct_member_redecl; 1554 1555 bool Invalid = false; 1556 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1557 FEnd = AnonRecord->field_end(); 1558 F != FEnd; ++F) { 1559 if ((*F)->getDeclName()) { 1560 if (CheckRedeclaration(Owner, (*F)->getDeclName(), 1561 (*F)->getLocation(), diagKind)) { 1562 // C++ [class.union]p2: 1563 // The names of the members of an anonymous union shall be 1564 // distinct from the names of any other entity in the 1565 // scope in which the anonymous union is declared. 1566 Invalid = true; 1567 } else { 1568 // C++ [class.union]p2: 1569 // For the purpose of name lookup, after the anonymous union 1570 // definition, the members of the anonymous union are 1571 // considered to have been defined in the scope in which the 1572 // anonymous union is declared. 1573 Owner->makeDeclVisibleInContext(*F); 1574 S->AddDecl(DeclPtrTy::make(*F)); 1575 IdResolver.AddDecl(*F); 1576 } 1577 } else if (const RecordType *InnerRecordType 1578 = (*F)->getType()->getAs<RecordType>()) { 1579 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1580 if (InnerRecord->isAnonymousStructOrUnion()) 1581 Invalid = Invalid || 1582 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1583 } 1584 } 1585 1586 return Invalid; 1587} 1588 1589/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1590/// anonymous structure or union. Anonymous unions are a C++ feature 1591/// (C++ [class.union]) and a GNU C extension; anonymous structures 1592/// are a GNU C and GNU C++ extension. 1593Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1594 RecordDecl *Record) { 1595 DeclContext *Owner = Record->getDeclContext(); 1596 1597 // Diagnose whether this anonymous struct/union is an extension. 1598 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1599 Diag(Record->getLocation(), diag::ext_anonymous_union); 1600 else if (!Record->isUnion()) 1601 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1602 1603 // C and C++ require different kinds of checks for anonymous 1604 // structs/unions. 1605 bool Invalid = false; 1606 if (getLangOptions().CPlusPlus) { 1607 const char* PrevSpec = 0; 1608 unsigned DiagID; 1609 // C++ [class.union]p3: 1610 // Anonymous unions declared in a named namespace or in the 1611 // global namespace shall be declared static. 1612 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1613 (isa<TranslationUnitDecl>(Owner) || 1614 (isa<NamespaceDecl>(Owner) && 1615 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1616 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1617 Invalid = true; 1618 1619 // Recover by adding 'static'. 1620 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1621 PrevSpec, DiagID); 1622 } 1623 // C++ [class.union]p3: 1624 // A storage class is not allowed in a declaration of an 1625 // anonymous union in a class scope. 1626 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1627 isa<RecordDecl>(Owner)) { 1628 Diag(DS.getStorageClassSpecLoc(), 1629 diag::err_anonymous_union_with_storage_spec); 1630 Invalid = true; 1631 1632 // Recover by removing the storage specifier. 1633 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1634 PrevSpec, DiagID); 1635 } 1636 1637 // C++ [class.union]p2: 1638 // The member-specification of an anonymous union shall only 1639 // define non-static data members. [Note: nested types and 1640 // functions cannot be declared within an anonymous union. ] 1641 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1642 MemEnd = Record->decls_end(); 1643 Mem != MemEnd; ++Mem) { 1644 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1645 // C++ [class.union]p3: 1646 // An anonymous union shall not have private or protected 1647 // members (clause 11). 1648 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1649 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1650 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1651 Invalid = true; 1652 } 1653 } else if ((*Mem)->isImplicit()) { 1654 // Any implicit members are fine. 1655 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1656 // This is a type that showed up in an 1657 // elaborated-type-specifier inside the anonymous struct or 1658 // union, but which actually declares a type outside of the 1659 // anonymous struct or union. It's okay. 1660 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1661 if (!MemRecord->isAnonymousStructOrUnion() && 1662 MemRecord->getDeclName()) { 1663 // This is a nested type declaration. 1664 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1665 << (int)Record->isUnion(); 1666 Invalid = true; 1667 } 1668 } else { 1669 // We have something that isn't a non-static data 1670 // member. Complain about it. 1671 unsigned DK = diag::err_anonymous_record_bad_member; 1672 if (isa<TypeDecl>(*Mem)) 1673 DK = diag::err_anonymous_record_with_type; 1674 else if (isa<FunctionDecl>(*Mem)) 1675 DK = diag::err_anonymous_record_with_function; 1676 else if (isa<VarDecl>(*Mem)) 1677 DK = diag::err_anonymous_record_with_static; 1678 Diag((*Mem)->getLocation(), DK) 1679 << (int)Record->isUnion(); 1680 Invalid = true; 1681 } 1682 } 1683 } 1684 1685 if (!Record->isUnion() && !Owner->isRecord()) { 1686 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1687 << (int)getLangOptions().CPlusPlus; 1688 Invalid = true; 1689 } 1690 1691 // Mock up a declarator. 1692 Declarator Dc(DS, Declarator::TypeNameContext); 1693 TypeSourceInfo *TInfo = 0; 1694 GetTypeForDeclarator(Dc, S, &TInfo); 1695 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1696 1697 // Create a declaration for this anonymous struct/union. 1698 NamedDecl *Anon = 0; 1699 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1700 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1701 /*IdentifierInfo=*/0, 1702 Context.getTypeDeclType(Record), 1703 TInfo, 1704 /*BitWidth=*/0, /*Mutable=*/false); 1705 Anon->setAccess(AS_public); 1706 if (getLangOptions().CPlusPlus) 1707 FieldCollector->Add(cast<FieldDecl>(Anon)); 1708 } else { 1709 VarDecl::StorageClass SC; 1710 switch (DS.getStorageClassSpec()) { 1711 default: assert(0 && "Unknown storage class!"); 1712 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1713 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1714 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1715 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1716 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1717 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1718 case DeclSpec::SCS_mutable: 1719 // mutable can only appear on non-static class members, so it's always 1720 // an error here 1721 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1722 Invalid = true; 1723 SC = VarDecl::None; 1724 break; 1725 } 1726 1727 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1728 /*IdentifierInfo=*/0, 1729 Context.getTypeDeclType(Record), 1730 TInfo, 1731 SC); 1732 } 1733 Anon->setImplicit(); 1734 1735 // Add the anonymous struct/union object to the current 1736 // context. We'll be referencing this object when we refer to one of 1737 // its members. 1738 Owner->addDecl(Anon); 1739 1740 // Inject the members of the anonymous struct/union into the owning 1741 // context and into the identifier resolver chain for name lookup 1742 // purposes. 1743 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1744 Invalid = true; 1745 1746 // Mark this as an anonymous struct/union type. Note that we do not 1747 // do this until after we have already checked and injected the 1748 // members of this anonymous struct/union type, because otherwise 1749 // the members could be injected twice: once by DeclContext when it 1750 // builds its lookup table, and once by 1751 // InjectAnonymousStructOrUnionMembers. 1752 Record->setAnonymousStructOrUnion(true); 1753 1754 if (Invalid) 1755 Anon->setInvalidDecl(); 1756 1757 return DeclPtrTy::make(Anon); 1758} 1759 1760 1761/// GetNameForDeclarator - Determine the full declaration name for the 1762/// given Declarator. 1763DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1764 return GetNameFromUnqualifiedId(D.getName()); 1765} 1766 1767/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1768DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1769 switch (Name.getKind()) { 1770 case UnqualifiedId::IK_Identifier: 1771 return DeclarationName(Name.Identifier); 1772 1773 case UnqualifiedId::IK_OperatorFunctionId: 1774 return Context.DeclarationNames.getCXXOperatorName( 1775 Name.OperatorFunctionId.Operator); 1776 1777 case UnqualifiedId::IK_LiteralOperatorId: 1778 return Context.DeclarationNames.getCXXLiteralOperatorName( 1779 Name.Identifier); 1780 1781 case UnqualifiedId::IK_ConversionFunctionId: { 1782 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1783 if (Ty.isNull()) 1784 return DeclarationName(); 1785 1786 return Context.DeclarationNames.getCXXConversionFunctionName( 1787 Context.getCanonicalType(Ty)); 1788 } 1789 1790 case UnqualifiedId::IK_ConstructorName: { 1791 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1792 if (Ty.isNull()) 1793 return DeclarationName(); 1794 1795 return Context.DeclarationNames.getCXXConstructorName( 1796 Context.getCanonicalType(Ty)); 1797 } 1798 1799 case UnqualifiedId::IK_DestructorName: { 1800 QualType Ty = GetTypeFromParser(Name.DestructorName); 1801 if (Ty.isNull()) 1802 return DeclarationName(); 1803 1804 return Context.DeclarationNames.getCXXDestructorName( 1805 Context.getCanonicalType(Ty)); 1806 } 1807 1808 case UnqualifiedId::IK_TemplateId: { 1809 TemplateName TName 1810 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1811 return Context.getNameForTemplate(TName); 1812 } 1813 } 1814 1815 assert(false && "Unknown name kind"); 1816 return DeclarationName(); 1817} 1818 1819/// isNearlyMatchingFunction - Determine whether the C++ functions 1820/// Declaration and Definition are "nearly" matching. This heuristic 1821/// is used to improve diagnostics in the case where an out-of-line 1822/// function definition doesn't match any declaration within 1823/// the class or namespace. 1824static bool isNearlyMatchingFunction(ASTContext &Context, 1825 FunctionDecl *Declaration, 1826 FunctionDecl *Definition) { 1827 if (Declaration->param_size() != Definition->param_size()) 1828 return false; 1829 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1830 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1831 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1832 1833 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1834 DefParamTy.getNonReferenceType())) 1835 return false; 1836 } 1837 1838 return true; 1839} 1840 1841Sema::DeclPtrTy 1842Sema::HandleDeclarator(Scope *S, Declarator &D, 1843 MultiTemplateParamsArg TemplateParamLists, 1844 bool IsFunctionDefinition) { 1845 DeclarationName Name = GetNameForDeclarator(D); 1846 1847 // All of these full declarators require an identifier. If it doesn't have 1848 // one, the ParsedFreeStandingDeclSpec action should be used. 1849 if (!Name) { 1850 if (!D.isInvalidType()) // Reject this if we think it is valid. 1851 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1852 diag::err_declarator_need_ident) 1853 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1854 return DeclPtrTy(); 1855 } 1856 1857 // The scope passed in may not be a decl scope. Zip up the scope tree until 1858 // we find one that is. 1859 while ((S->getFlags() & Scope::DeclScope) == 0 || 1860 (S->getFlags() & Scope::TemplateParamScope) != 0) 1861 S = S->getParent(); 1862 1863 // If this is an out-of-line definition of a member of a class template 1864 // or class template partial specialization, we may need to rebuild the 1865 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1866 // for more information. 1867 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1868 // handle expressions properly. 1869 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1870 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1871 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1872 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1873 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1874 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1875 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1876 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1877 // FIXME: Preserve type source info. 1878 QualType T = GetTypeFromParser(DS.getTypeRep()); 1879 EnterDeclaratorContext(S, DC); 1880 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1881 ExitDeclaratorContext(S); 1882 if (T.isNull()) 1883 return DeclPtrTy(); 1884 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1885 } 1886 } 1887 1888 DeclContext *DC; 1889 NamedDecl *New; 1890 1891 TypeSourceInfo *TInfo = 0; 1892 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1893 1894 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1895 ForRedeclaration); 1896 1897 // See if this is a redefinition of a variable in the same scope. 1898 if (D.getCXXScopeSpec().isInvalid()) { 1899 DC = CurContext; 1900 D.setInvalidType(); 1901 } else if (!D.getCXXScopeSpec().isSet()) { 1902 bool IsLinkageLookup = false; 1903 1904 // If the declaration we're planning to build will be a function 1905 // or object with linkage, then look for another declaration with 1906 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1907 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1908 /* Do nothing*/; 1909 else if (R->isFunctionType()) { 1910 if (CurContext->isFunctionOrMethod() || 1911 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1912 IsLinkageLookup = true; 1913 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1914 IsLinkageLookup = true; 1915 else if (CurContext->getLookupContext()->isTranslationUnit() && 1916 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1917 IsLinkageLookup = true; 1918 1919 if (IsLinkageLookup) 1920 Previous.clear(LookupRedeclarationWithLinkage); 1921 1922 DC = CurContext; 1923 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1924 } else { // Something like "int foo::x;" 1925 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1926 1927 if (!DC) { 1928 // If we could not compute the declaration context, it's because the 1929 // declaration context is dependent but does not refer to a class, 1930 // class template, or class template partial specialization. Complain 1931 // and return early, to avoid the coming semantic disaster. 1932 Diag(D.getIdentifierLoc(), 1933 diag::err_template_qualified_declarator_no_match) 1934 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1935 << D.getCXXScopeSpec().getRange(); 1936 return DeclPtrTy(); 1937 } 1938 1939 if (!DC->isDependentContext() && 1940 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1941 return DeclPtrTy(); 1942 1943 LookupQualifiedName(Previous, DC); 1944 1945 // Don't consider using declarations as previous declarations for 1946 // out-of-line members. 1947 RemoveUsingDecls(Previous); 1948 1949 // C++ 7.3.1.2p2: 1950 // Members (including explicit specializations of templates) of a named 1951 // namespace can also be defined outside that namespace by explicit 1952 // qualification of the name being defined, provided that the entity being 1953 // defined was already declared in the namespace and the definition appears 1954 // after the point of declaration in a namespace that encloses the 1955 // declarations namespace. 1956 // 1957 // Note that we only check the context at this point. We don't yet 1958 // have enough information to make sure that PrevDecl is actually 1959 // the declaration we want to match. For example, given: 1960 // 1961 // class X { 1962 // void f(); 1963 // void f(float); 1964 // }; 1965 // 1966 // void X::f(int) { } // ill-formed 1967 // 1968 // In this case, PrevDecl will point to the overload set 1969 // containing the two f's declared in X, but neither of them 1970 // matches. 1971 1972 // First check whether we named the global scope. 1973 if (isa<TranslationUnitDecl>(DC)) { 1974 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1975 << Name << D.getCXXScopeSpec().getRange(); 1976 } else { 1977 DeclContext *Cur = CurContext; 1978 while (isa<LinkageSpecDecl>(Cur)) 1979 Cur = Cur->getParent(); 1980 if (!Cur->Encloses(DC)) { 1981 // The qualifying scope doesn't enclose the original declaration. 1982 // Emit diagnostic based on current scope. 1983 SourceLocation L = D.getIdentifierLoc(); 1984 SourceRange R = D.getCXXScopeSpec().getRange(); 1985 if (isa<FunctionDecl>(Cur)) 1986 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1987 else 1988 Diag(L, diag::err_invalid_declarator_scope) 1989 << Name << cast<NamedDecl>(DC) << R; 1990 D.setInvalidType(); 1991 } 1992 } 1993 } 1994 1995 if (Previous.isSingleResult() && 1996 Previous.getFoundDecl()->isTemplateParameter()) { 1997 // Maybe we will complain about the shadowed template parameter. 1998 if (!D.isInvalidType()) 1999 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2000 Previous.getFoundDecl())) 2001 D.setInvalidType(); 2002 2003 // Just pretend that we didn't see the previous declaration. 2004 Previous.clear(); 2005 } 2006 2007 // In C++, the previous declaration we find might be a tag type 2008 // (class or enum). In this case, the new declaration will hide the 2009 // tag type. Note that this does does not apply if we're declaring a 2010 // typedef (C++ [dcl.typedef]p4). 2011 if (Previous.isSingleTagDecl() && 2012 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2013 Previous.clear(); 2014 2015 bool Redeclaration = false; 2016 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2017 if (TemplateParamLists.size()) { 2018 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2019 return DeclPtrTy(); 2020 } 2021 2022 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2023 } else if (R->isFunctionType()) { 2024 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2025 move(TemplateParamLists), 2026 IsFunctionDefinition, Redeclaration); 2027 } else { 2028 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2029 move(TemplateParamLists), 2030 Redeclaration); 2031 } 2032 2033 if (New == 0) 2034 return DeclPtrTy(); 2035 2036 // If this has an identifier and is not an invalid redeclaration or 2037 // function template specialization, add it to the scope stack. 2038 if (Name && !(Redeclaration && New->isInvalidDecl())) 2039 PushOnScopeChains(New, S); 2040 2041 return DeclPtrTy::make(New); 2042} 2043 2044/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2045/// types into constant array types in certain situations which would otherwise 2046/// be errors (for GCC compatibility). 2047static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2048 ASTContext &Context, 2049 bool &SizeIsNegative) { 2050 // This method tries to turn a variable array into a constant 2051 // array even when the size isn't an ICE. This is necessary 2052 // for compatibility with code that depends on gcc's buggy 2053 // constant expression folding, like struct {char x[(int)(char*)2];} 2054 SizeIsNegative = false; 2055 2056 QualifierCollector Qs; 2057 const Type *Ty = Qs.strip(T); 2058 2059 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2060 QualType Pointee = PTy->getPointeeType(); 2061 QualType FixedType = 2062 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2063 if (FixedType.isNull()) return FixedType; 2064 FixedType = Context.getPointerType(FixedType); 2065 return Qs.apply(FixedType); 2066 } 2067 2068 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2069 if (!VLATy) 2070 return QualType(); 2071 // FIXME: We should probably handle this case 2072 if (VLATy->getElementType()->isVariablyModifiedType()) 2073 return QualType(); 2074 2075 Expr::EvalResult EvalResult; 2076 if (!VLATy->getSizeExpr() || 2077 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2078 !EvalResult.Val.isInt()) 2079 return QualType(); 2080 2081 llvm::APSInt &Res = EvalResult.Val.getInt(); 2082 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2083 // TODO: preserve the size expression in declarator info 2084 return Context.getConstantArrayType(VLATy->getElementType(), 2085 Res, ArrayType::Normal, 0); 2086 } 2087 2088 SizeIsNegative = true; 2089 return QualType(); 2090} 2091 2092/// \brief Register the given locally-scoped external C declaration so 2093/// that it can be found later for redeclarations 2094void 2095Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2096 const LookupResult &Previous, 2097 Scope *S) { 2098 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2099 "Decl is not a locally-scoped decl!"); 2100 // Note that we have a locally-scoped external with this name. 2101 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2102 2103 if (!Previous.isSingleResult()) 2104 return; 2105 2106 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2107 2108 // If there was a previous declaration of this variable, it may be 2109 // in our identifier chain. Update the identifier chain with the new 2110 // declaration. 2111 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2112 // The previous declaration was found on the identifer resolver 2113 // chain, so remove it from its scope. 2114 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2115 S = S->getParent(); 2116 2117 if (S) 2118 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2119 } 2120} 2121 2122/// \brief Diagnose function specifiers on a declaration of an identifier that 2123/// does not identify a function. 2124void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2125 // FIXME: We should probably indicate the identifier in question to avoid 2126 // confusion for constructs like "inline int a(), b;" 2127 if (D.getDeclSpec().isInlineSpecified()) 2128 Diag(D.getDeclSpec().getInlineSpecLoc(), 2129 diag::err_inline_non_function); 2130 2131 if (D.getDeclSpec().isVirtualSpecified()) 2132 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2133 diag::err_virtual_non_function); 2134 2135 if (D.getDeclSpec().isExplicitSpecified()) 2136 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2137 diag::err_explicit_non_function); 2138} 2139 2140NamedDecl* 2141Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2142 QualType R, TypeSourceInfo *TInfo, 2143 LookupResult &Previous, bool &Redeclaration) { 2144 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2145 if (D.getCXXScopeSpec().isSet()) { 2146 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2147 << D.getCXXScopeSpec().getRange(); 2148 D.setInvalidType(); 2149 // Pretend we didn't see the scope specifier. 2150 DC = 0; 2151 } 2152 2153 if (getLangOptions().CPlusPlus) { 2154 // Check that there are no default arguments (C++ only). 2155 CheckExtraCXXDefaultArguments(D); 2156 } 2157 2158 DiagnoseFunctionSpecifiers(D); 2159 2160 if (D.getDeclSpec().isThreadSpecified()) 2161 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2162 2163 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2164 if (!NewTD) return 0; 2165 2166 // Handle attributes prior to checking for duplicates in MergeVarDecl 2167 ProcessDeclAttributes(S, NewTD, D); 2168 2169 // Merge the decl with the existing one if appropriate. If the decl is 2170 // in an outer scope, it isn't the same thing. 2171 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2172 if (!Previous.empty()) { 2173 Redeclaration = true; 2174 MergeTypeDefDecl(NewTD, Previous); 2175 } 2176 2177 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2178 // then it shall have block scope. 2179 QualType T = NewTD->getUnderlyingType(); 2180 if (T->isVariablyModifiedType()) { 2181 CurFunctionNeedsScopeChecking = true; 2182 2183 if (S->getFnParent() == 0) { 2184 bool SizeIsNegative; 2185 QualType FixedTy = 2186 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2187 if (!FixedTy.isNull()) { 2188 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2189 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2190 } else { 2191 if (SizeIsNegative) 2192 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2193 else if (T->isVariableArrayType()) 2194 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2195 else 2196 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2197 NewTD->setInvalidDecl(); 2198 } 2199 } 2200 } 2201 2202 // If this is the C FILE type, notify the AST context. 2203 if (IdentifierInfo *II = NewTD->getIdentifier()) 2204 if (!NewTD->isInvalidDecl() && 2205 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2206 if (II->isStr("FILE")) 2207 Context.setFILEDecl(NewTD); 2208 else if (II->isStr("jmp_buf")) 2209 Context.setjmp_bufDecl(NewTD); 2210 else if (II->isStr("sigjmp_buf")) 2211 Context.setsigjmp_bufDecl(NewTD); 2212 } 2213 2214 return NewTD; 2215} 2216 2217/// \brief Determines whether the given declaration is an out-of-scope 2218/// previous declaration. 2219/// 2220/// This routine should be invoked when name lookup has found a 2221/// previous declaration (PrevDecl) that is not in the scope where a 2222/// new declaration by the same name is being introduced. If the new 2223/// declaration occurs in a local scope, previous declarations with 2224/// linkage may still be considered previous declarations (C99 2225/// 6.2.2p4-5, C++ [basic.link]p6). 2226/// 2227/// \param PrevDecl the previous declaration found by name 2228/// lookup 2229/// 2230/// \param DC the context in which the new declaration is being 2231/// declared. 2232/// 2233/// \returns true if PrevDecl is an out-of-scope previous declaration 2234/// for a new delcaration with the same name. 2235static bool 2236isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2237 ASTContext &Context) { 2238 if (!PrevDecl) 2239 return 0; 2240 2241 if (!PrevDecl->hasLinkage()) 2242 return false; 2243 2244 if (Context.getLangOptions().CPlusPlus) { 2245 // C++ [basic.link]p6: 2246 // If there is a visible declaration of an entity with linkage 2247 // having the same name and type, ignoring entities declared 2248 // outside the innermost enclosing namespace scope, the block 2249 // scope declaration declares that same entity and receives the 2250 // linkage of the previous declaration. 2251 DeclContext *OuterContext = DC->getLookupContext(); 2252 if (!OuterContext->isFunctionOrMethod()) 2253 // This rule only applies to block-scope declarations. 2254 return false; 2255 else { 2256 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2257 if (PrevOuterContext->isRecord()) 2258 // We found a member function: ignore it. 2259 return false; 2260 else { 2261 // Find the innermost enclosing namespace for the new and 2262 // previous declarations. 2263 while (!OuterContext->isFileContext()) 2264 OuterContext = OuterContext->getParent(); 2265 while (!PrevOuterContext->isFileContext()) 2266 PrevOuterContext = PrevOuterContext->getParent(); 2267 2268 // The previous declaration is in a different namespace, so it 2269 // isn't the same function. 2270 if (OuterContext->getPrimaryContext() != 2271 PrevOuterContext->getPrimaryContext()) 2272 return false; 2273 } 2274 } 2275 } 2276 2277 return true; 2278} 2279 2280NamedDecl* 2281Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2282 QualType R, TypeSourceInfo *TInfo, 2283 LookupResult &Previous, 2284 MultiTemplateParamsArg TemplateParamLists, 2285 bool &Redeclaration) { 2286 DeclarationName Name = GetNameForDeclarator(D); 2287 2288 // Check that there are no default arguments (C++ only). 2289 if (getLangOptions().CPlusPlus) 2290 CheckExtraCXXDefaultArguments(D); 2291 2292 VarDecl *NewVD; 2293 VarDecl::StorageClass SC; 2294 switch (D.getDeclSpec().getStorageClassSpec()) { 2295 default: assert(0 && "Unknown storage class!"); 2296 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2297 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2298 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2299 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2300 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2301 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2302 case DeclSpec::SCS_mutable: 2303 // mutable can only appear on non-static class members, so it's always 2304 // an error here 2305 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2306 D.setInvalidType(); 2307 SC = VarDecl::None; 2308 break; 2309 } 2310 2311 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2312 if (!II) { 2313 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2314 << Name.getAsString(); 2315 return 0; 2316 } 2317 2318 DiagnoseFunctionSpecifiers(D); 2319 2320 if (!DC->isRecord() && S->getFnParent() == 0) { 2321 // C99 6.9p2: The storage-class specifiers auto and register shall not 2322 // appear in the declaration specifiers in an external declaration. 2323 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2324 2325 // If this is a register variable with an asm label specified, then this 2326 // is a GNU extension. 2327 if (SC == VarDecl::Register && D.getAsmLabel()) 2328 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2329 else 2330 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2331 D.setInvalidType(); 2332 } 2333 } 2334 if (DC->isRecord() && !CurContext->isRecord()) { 2335 // This is an out-of-line definition of a static data member. 2336 if (SC == VarDecl::Static) { 2337 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2338 diag::err_static_out_of_line) 2339 << CodeModificationHint::CreateRemoval( 2340 D.getDeclSpec().getStorageClassSpecLoc()); 2341 } else if (SC == VarDecl::None) 2342 SC = VarDecl::Static; 2343 } 2344 if (SC == VarDecl::Static) { 2345 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2346 if (RD->isLocalClass()) 2347 Diag(D.getIdentifierLoc(), 2348 diag::err_static_data_member_not_allowed_in_local_class) 2349 << Name << RD->getDeclName(); 2350 } 2351 } 2352 2353 // Match up the template parameter lists with the scope specifier, then 2354 // determine whether we have a template or a template specialization. 2355 bool isExplicitSpecialization = false; 2356 if (TemplateParameterList *TemplateParams 2357 = MatchTemplateParametersToScopeSpecifier( 2358 D.getDeclSpec().getSourceRange().getBegin(), 2359 D.getCXXScopeSpec(), 2360 (TemplateParameterList**)TemplateParamLists.get(), 2361 TemplateParamLists.size(), 2362 isExplicitSpecialization)) { 2363 if (TemplateParams->size() > 0) { 2364 // There is no such thing as a variable template. 2365 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2366 << II 2367 << SourceRange(TemplateParams->getTemplateLoc(), 2368 TemplateParams->getRAngleLoc()); 2369 return 0; 2370 } else { 2371 // There is an extraneous 'template<>' for this variable. Complain 2372 // about it, but allow the declaration of the variable. 2373 Diag(TemplateParams->getTemplateLoc(), 2374 diag::err_template_variable_noparams) 2375 << II 2376 << SourceRange(TemplateParams->getTemplateLoc(), 2377 TemplateParams->getRAngleLoc()); 2378 2379 isExplicitSpecialization = true; 2380 } 2381 } 2382 2383 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2384 II, R, TInfo, SC); 2385 2386 if (D.isInvalidType()) 2387 NewVD->setInvalidDecl(); 2388 2389 if (D.getDeclSpec().isThreadSpecified()) { 2390 if (NewVD->hasLocalStorage()) 2391 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2392 else if (!Context.Target.isTLSSupported()) 2393 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2394 else 2395 NewVD->setThreadSpecified(true); 2396 } 2397 2398 // Set the lexical context. If the declarator has a C++ scope specifier, the 2399 // lexical context will be different from the semantic context. 2400 NewVD->setLexicalDeclContext(CurContext); 2401 2402 // Handle attributes prior to checking for duplicates in MergeVarDecl 2403 ProcessDeclAttributes(S, NewVD, D); 2404 2405 // Handle GNU asm-label extension (encoded as an attribute). 2406 if (Expr *E = (Expr*) D.getAsmLabel()) { 2407 // The parser guarantees this is a string. 2408 StringLiteral *SE = cast<StringLiteral>(E); 2409 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2410 } 2411 2412 // Don't consider existing declarations that are in a different 2413 // scope and are out-of-semantic-context declarations (if the new 2414 // declaration has linkage). 2415 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2416 2417 // Merge the decl with the existing one if appropriate. 2418 if (!Previous.empty()) { 2419 if (Previous.isSingleResult() && 2420 isa<FieldDecl>(Previous.getFoundDecl()) && 2421 D.getCXXScopeSpec().isSet()) { 2422 // The user tried to define a non-static data member 2423 // out-of-line (C++ [dcl.meaning]p1). 2424 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2425 << D.getCXXScopeSpec().getRange(); 2426 Previous.clear(); 2427 NewVD->setInvalidDecl(); 2428 } 2429 } else if (D.getCXXScopeSpec().isSet()) { 2430 // No previous declaration in the qualifying scope. 2431 Diag(D.getIdentifierLoc(), diag::err_no_member) 2432 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2433 << D.getCXXScopeSpec().getRange(); 2434 NewVD->setInvalidDecl(); 2435 } 2436 2437 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2438 2439 // This is an explicit specialization of a static data member. Check it. 2440 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2441 CheckMemberSpecialization(NewVD, Previous)) 2442 NewVD->setInvalidDecl(); 2443 2444 // attributes declared post-definition are currently ignored 2445 if (Previous.isSingleResult()) { 2446 const VarDecl *Def = 0; 2447 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2448 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2449 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2450 Diag(Def->getLocation(), diag::note_previous_definition); 2451 } 2452 } 2453 2454 // If this is a locally-scoped extern C variable, update the map of 2455 // such variables. 2456 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2457 !NewVD->isInvalidDecl()) 2458 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2459 2460 return NewVD; 2461} 2462 2463/// \brief Perform semantic checking on a newly-created variable 2464/// declaration. 2465/// 2466/// This routine performs all of the type-checking required for a 2467/// variable declaration once it has been built. It is used both to 2468/// check variables after they have been parsed and their declarators 2469/// have been translated into a declaration, and to check variables 2470/// that have been instantiated from a template. 2471/// 2472/// Sets NewVD->isInvalidDecl() if an error was encountered. 2473void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2474 LookupResult &Previous, 2475 bool &Redeclaration) { 2476 // If the decl is already known invalid, don't check it. 2477 if (NewVD->isInvalidDecl()) 2478 return; 2479 2480 QualType T = NewVD->getType(); 2481 2482 if (T->isObjCInterfaceType()) { 2483 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2484 return NewVD->setInvalidDecl(); 2485 } 2486 2487 // Emit an error if an address space was applied to decl with local storage. 2488 // This includes arrays of objects with address space qualifiers, but not 2489 // automatic variables that point to other address spaces. 2490 // ISO/IEC TR 18037 S5.1.2 2491 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2492 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2493 return NewVD->setInvalidDecl(); 2494 } 2495 2496 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2497 && !NewVD->hasAttr<BlocksAttr>()) 2498 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2499 2500 bool isVM = T->isVariablyModifiedType(); 2501 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2502 NewVD->hasAttr<BlocksAttr>()) 2503 CurFunctionNeedsScopeChecking = true; 2504 2505 if ((isVM && NewVD->hasLinkage()) || 2506 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2507 bool SizeIsNegative; 2508 QualType FixedTy = 2509 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2510 2511 if (FixedTy.isNull() && T->isVariableArrayType()) { 2512 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2513 // FIXME: This won't give the correct result for 2514 // int a[10][n]; 2515 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2516 2517 if (NewVD->isFileVarDecl()) 2518 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2519 << SizeRange; 2520 else if (NewVD->getStorageClass() == VarDecl::Static) 2521 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2522 << SizeRange; 2523 else 2524 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2525 << SizeRange; 2526 return NewVD->setInvalidDecl(); 2527 } 2528 2529 if (FixedTy.isNull()) { 2530 if (NewVD->isFileVarDecl()) 2531 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2532 else 2533 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2534 return NewVD->setInvalidDecl(); 2535 } 2536 2537 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2538 NewVD->setType(FixedTy); 2539 } 2540 2541 if (Previous.empty() && NewVD->isExternC()) { 2542 // Since we did not find anything by this name and we're declaring 2543 // an extern "C" variable, look for a non-visible extern "C" 2544 // declaration with the same name. 2545 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2546 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2547 if (Pos != LocallyScopedExternalDecls.end()) 2548 Previous.addDecl(Pos->second); 2549 } 2550 2551 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2552 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2553 << T; 2554 return NewVD->setInvalidDecl(); 2555 } 2556 2557 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2558 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2559 return NewVD->setInvalidDecl(); 2560 } 2561 2562 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2563 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2564 return NewVD->setInvalidDecl(); 2565 } 2566 2567 if (!Previous.empty()) { 2568 Redeclaration = true; 2569 MergeVarDecl(NewVD, Previous); 2570 } 2571} 2572 2573/// \brief Data used with FindOverriddenMethod 2574struct FindOverriddenMethodData { 2575 Sema *S; 2576 CXXMethodDecl *Method; 2577}; 2578 2579/// \brief Member lookup function that determines whether a given C++ 2580/// method overrides a method in a base class, to be used with 2581/// CXXRecordDecl::lookupInBases(). 2582static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2583 CXXBasePath &Path, 2584 void *UserData) { 2585 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2586 2587 FindOverriddenMethodData *Data 2588 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2589 2590 DeclarationName Name = Data->Method->getDeclName(); 2591 2592 // FIXME: Do we care about other names here too? 2593 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2594 // We really want to find the base class constructor here. 2595 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2596 CanQualType CT = Data->S->Context.getCanonicalType(T); 2597 2598 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2599 } 2600 2601 for (Path.Decls = BaseRecord->lookup(Name); 2602 Path.Decls.first != Path.Decls.second; 2603 ++Path.Decls.first) { 2604 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2605 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2606 return true; 2607 } 2608 } 2609 2610 return false; 2611} 2612 2613/// AddOverriddenMethods - See if a method overrides any in the base classes, 2614/// and if so, check that it's a valid override and remember it. 2615void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2616 // Look for virtual methods in base classes that this method might override. 2617 CXXBasePaths Paths; 2618 FindOverriddenMethodData Data; 2619 Data.Method = MD; 2620 Data.S = this; 2621 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2622 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2623 E = Paths.found_decls_end(); I != E; ++I) { 2624 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2625 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2626 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2627 !CheckOverridingFunctionAttributes(MD, OldMD)) 2628 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2629 } 2630 } 2631 } 2632} 2633 2634NamedDecl* 2635Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2636 QualType R, TypeSourceInfo *TInfo, 2637 LookupResult &Previous, 2638 MultiTemplateParamsArg TemplateParamLists, 2639 bool IsFunctionDefinition, bool &Redeclaration) { 2640 assert(R.getTypePtr()->isFunctionType()); 2641 2642 DeclarationName Name = GetNameForDeclarator(D); 2643 FunctionDecl::StorageClass SC = FunctionDecl::None; 2644 switch (D.getDeclSpec().getStorageClassSpec()) { 2645 default: assert(0 && "Unknown storage class!"); 2646 case DeclSpec::SCS_auto: 2647 case DeclSpec::SCS_register: 2648 case DeclSpec::SCS_mutable: 2649 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2650 diag::err_typecheck_sclass_func); 2651 D.setInvalidType(); 2652 break; 2653 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2654 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2655 case DeclSpec::SCS_static: { 2656 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2657 // C99 6.7.1p5: 2658 // The declaration of an identifier for a function that has 2659 // block scope shall have no explicit storage-class specifier 2660 // other than extern 2661 // See also (C++ [dcl.stc]p4). 2662 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2663 diag::err_static_block_func); 2664 SC = FunctionDecl::None; 2665 } else 2666 SC = FunctionDecl::Static; 2667 break; 2668 } 2669 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2670 } 2671 2672 if (D.getDeclSpec().isThreadSpecified()) 2673 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2674 2675 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2676 bool isInline = D.getDeclSpec().isInlineSpecified(); 2677 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2678 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2679 2680 // Check that the return type is not an abstract class type. 2681 // For record types, this is done by the AbstractClassUsageDiagnoser once 2682 // the class has been completely parsed. 2683 if (!DC->isRecord() && 2684 RequireNonAbstractType(D.getIdentifierLoc(), 2685 R->getAs<FunctionType>()->getResultType(), 2686 diag::err_abstract_type_in_decl, 2687 AbstractReturnType)) 2688 D.setInvalidType(); 2689 2690 // Do not allow returning a objc interface by-value. 2691 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2692 Diag(D.getIdentifierLoc(), 2693 diag::err_object_cannot_be_passed_returned_by_value) << 0 2694 << R->getAs<FunctionType>()->getResultType(); 2695 D.setInvalidType(); 2696 } 2697 2698 bool isVirtualOkay = false; 2699 FunctionDecl *NewFD; 2700 2701 if (isFriend) { 2702 // C++ [class.friend]p5 2703 // A function can be defined in a friend declaration of a 2704 // class . . . . Such a function is implicitly inline. 2705 isInline |= IsFunctionDefinition; 2706 } 2707 2708 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2709 // This is a C++ constructor declaration. 2710 assert(DC->isRecord() && 2711 "Constructors can only be declared in a member context"); 2712 2713 R = CheckConstructorDeclarator(D, R, SC); 2714 2715 // Create the new declaration 2716 NewFD = CXXConstructorDecl::Create(Context, 2717 cast<CXXRecordDecl>(DC), 2718 D.getIdentifierLoc(), Name, R, TInfo, 2719 isExplicit, isInline, 2720 /*isImplicitlyDeclared=*/false); 2721 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2722 // This is a C++ destructor declaration. 2723 if (DC->isRecord()) { 2724 R = CheckDestructorDeclarator(D, SC); 2725 2726 NewFD = CXXDestructorDecl::Create(Context, 2727 cast<CXXRecordDecl>(DC), 2728 D.getIdentifierLoc(), Name, R, 2729 isInline, 2730 /*isImplicitlyDeclared=*/false); 2731 2732 isVirtualOkay = true; 2733 } else { 2734 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2735 2736 // Create a FunctionDecl to satisfy the function definition parsing 2737 // code path. 2738 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2739 Name, R, TInfo, SC, isInline, 2740 /*hasPrototype=*/true); 2741 D.setInvalidType(); 2742 } 2743 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2744 if (!DC->isRecord()) { 2745 Diag(D.getIdentifierLoc(), 2746 diag::err_conv_function_not_member); 2747 return 0; 2748 } 2749 2750 CheckConversionDeclarator(D, R, SC); 2751 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2752 D.getIdentifierLoc(), Name, R, TInfo, 2753 isInline, isExplicit); 2754 2755 isVirtualOkay = true; 2756 } else if (DC->isRecord()) { 2757 // If the of the function is the same as the name of the record, then this 2758 // must be an invalid constructor that has a return type. 2759 // (The parser checks for a return type and makes the declarator a 2760 // constructor if it has no return type). 2761 // must have an invalid constructor that has a return type 2762 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2763 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2764 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2765 << SourceRange(D.getIdentifierLoc()); 2766 return 0; 2767 } 2768 2769 bool isStatic = SC == FunctionDecl::Static; 2770 2771 // [class.free]p1: 2772 // Any allocation function for a class T is a static member 2773 // (even if not explicitly declared static). 2774 if (Name.getCXXOverloadedOperator() == OO_New || 2775 Name.getCXXOverloadedOperator() == OO_Array_New) 2776 isStatic = true; 2777 2778 // [class.free]p6 Any deallocation function for a class X is a static member 2779 // (even if not explicitly declared static). 2780 if (Name.getCXXOverloadedOperator() == OO_Delete || 2781 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2782 isStatic = true; 2783 2784 // This is a C++ method declaration. 2785 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2786 D.getIdentifierLoc(), Name, R, TInfo, 2787 isStatic, isInline); 2788 2789 isVirtualOkay = !isStatic; 2790 } else { 2791 // Determine whether the function was written with a 2792 // prototype. This true when: 2793 // - we're in C++ (where every function has a prototype), 2794 // - there is a prototype in the declarator, or 2795 // - the type R of the function is some kind of typedef or other reference 2796 // to a type name (which eventually refers to a function type). 2797 bool HasPrototype = 2798 getLangOptions().CPlusPlus || 2799 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2800 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2801 2802 NewFD = FunctionDecl::Create(Context, DC, 2803 D.getIdentifierLoc(), 2804 Name, R, TInfo, SC, isInline, HasPrototype); 2805 } 2806 2807 if (D.isInvalidType()) 2808 NewFD->setInvalidDecl(); 2809 2810 // Set the lexical context. If the declarator has a C++ 2811 // scope specifier, or is the object of a friend declaration, the 2812 // lexical context will be different from the semantic context. 2813 NewFD->setLexicalDeclContext(CurContext); 2814 2815 // Match up the template parameter lists with the scope specifier, then 2816 // determine whether we have a template or a template specialization. 2817 FunctionTemplateDecl *FunctionTemplate = 0; 2818 bool isExplicitSpecialization = false; 2819 bool isFunctionTemplateSpecialization = false; 2820 if (TemplateParameterList *TemplateParams 2821 = MatchTemplateParametersToScopeSpecifier( 2822 D.getDeclSpec().getSourceRange().getBegin(), 2823 D.getCXXScopeSpec(), 2824 (TemplateParameterList**)TemplateParamLists.get(), 2825 TemplateParamLists.size(), 2826 isExplicitSpecialization)) { 2827 if (TemplateParams->size() > 0) { 2828 // This is a function template 2829 2830 // Check that we can declare a template here. 2831 if (CheckTemplateDeclScope(S, TemplateParams)) 2832 return 0; 2833 2834 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2835 NewFD->getLocation(), 2836 Name, TemplateParams, 2837 NewFD); 2838 FunctionTemplate->setLexicalDeclContext(CurContext); 2839 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2840 } else { 2841 // This is a function template specialization. 2842 isFunctionTemplateSpecialization = true; 2843 } 2844 2845 // FIXME: Free this memory properly. 2846 TemplateParamLists.release(); 2847 } 2848 2849 // C++ [dcl.fct.spec]p5: 2850 // The virtual specifier shall only be used in declarations of 2851 // nonstatic class member functions that appear within a 2852 // member-specification of a class declaration; see 10.3. 2853 // 2854 if (isVirtual && !NewFD->isInvalidDecl()) { 2855 if (!isVirtualOkay) { 2856 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2857 diag::err_virtual_non_function); 2858 } else if (!CurContext->isRecord()) { 2859 // 'virtual' was specified outside of the class. 2860 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2861 << CodeModificationHint::CreateRemoval( 2862 D.getDeclSpec().getVirtualSpecLoc()); 2863 } else { 2864 // Okay: Add virtual to the method. 2865 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2866 CurClass->setMethodAsVirtual(NewFD); 2867 } 2868 } 2869 2870 // Filter out previous declarations that don't match the scope. 2871 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2872 2873 if (isFriend) { 2874 // DC is the namespace in which the function is being declared. 2875 assert((DC->isFileContext() || !Previous.empty()) && 2876 "previously-undeclared friend function being created " 2877 "in a non-namespace context"); 2878 2879 if (FunctionTemplate) { 2880 FunctionTemplate->setObjectOfFriendDecl( 2881 /* PreviouslyDeclared= */ !Previous.empty()); 2882 FunctionTemplate->setAccess(AS_public); 2883 } 2884 else 2885 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2886 2887 NewFD->setAccess(AS_public); 2888 } 2889 2890 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2891 !CurContext->isRecord()) { 2892 // C++ [class.static]p1: 2893 // A data or function member of a class may be declared static 2894 // in a class definition, in which case it is a static member of 2895 // the class. 2896 2897 // Complain about the 'static' specifier if it's on an out-of-line 2898 // member function definition. 2899 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2900 diag::err_static_out_of_line) 2901 << CodeModificationHint::CreateRemoval( 2902 D.getDeclSpec().getStorageClassSpecLoc()); 2903 } 2904 2905 // Handle GNU asm-label extension (encoded as an attribute). 2906 if (Expr *E = (Expr*) D.getAsmLabel()) { 2907 // The parser guarantees this is a string. 2908 StringLiteral *SE = cast<StringLiteral>(E); 2909 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2910 } 2911 2912 // Copy the parameter declarations from the declarator D to the function 2913 // declaration NewFD, if they are available. First scavenge them into Params. 2914 llvm::SmallVector<ParmVarDecl*, 16> Params; 2915 if (D.getNumTypeObjects() > 0) { 2916 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2917 2918 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2919 // function that takes no arguments, not a function that takes a 2920 // single void argument. 2921 // We let through "const void" here because Sema::GetTypeForDeclarator 2922 // already checks for that case. 2923 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2924 FTI.ArgInfo[0].Param && 2925 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2926 // Empty arg list, don't push any params. 2927 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2928 2929 // In C++, the empty parameter-type-list must be spelled "void"; a 2930 // typedef of void is not permitted. 2931 if (getLangOptions().CPlusPlus && 2932 Param->getType().getUnqualifiedType() != Context.VoidTy) 2933 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2934 // FIXME: Leaks decl? 2935 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2936 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2937 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2938 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2939 Param->setDeclContext(NewFD); 2940 Params.push_back(Param); 2941 } 2942 } 2943 2944 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2945 // When we're declaring a function with a typedef, typeof, etc as in the 2946 // following example, we'll need to synthesize (unnamed) 2947 // parameters for use in the declaration. 2948 // 2949 // @code 2950 // typedef void fn(int); 2951 // fn f; 2952 // @endcode 2953 2954 // Synthesize a parameter for each argument type. 2955 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2956 AE = FT->arg_type_end(); AI != AE; ++AI) { 2957 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2958 SourceLocation(), 0, 2959 *AI, /*TInfo=*/0, 2960 VarDecl::None, 0); 2961 Param->setImplicit(); 2962 Params.push_back(Param); 2963 } 2964 } else { 2965 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2966 "Should not need args for typedef of non-prototype fn"); 2967 } 2968 // Finally, we know we have the right number of parameters, install them. 2969 NewFD->setParams(Context, Params.data(), Params.size()); 2970 2971 // If the declarator is a template-id, translate the parser's template 2972 // argument list into our AST format. 2973 bool HasExplicitTemplateArgs = false; 2974 TemplateArgumentListInfo TemplateArgs; 2975 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2976 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2977 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 2978 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 2979 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2980 TemplateId->getTemplateArgs(), 2981 TemplateId->NumArgs); 2982 translateTemplateArguments(TemplateArgsPtr, 2983 TemplateArgs); 2984 TemplateArgsPtr.release(); 2985 2986 HasExplicitTemplateArgs = true; 2987 2988 if (FunctionTemplate) { 2989 // FIXME: Diagnose function template with explicit template 2990 // arguments. 2991 HasExplicitTemplateArgs = false; 2992 } else if (!isFunctionTemplateSpecialization && 2993 !D.getDeclSpec().isFriendSpecified()) { 2994 // We have encountered something that the user meant to be a 2995 // specialization (because it has explicitly-specified template 2996 // arguments) but that was not introduced with a "template<>" (or had 2997 // too few of them). 2998 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2999 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3000 << CodeModificationHint::CreateInsertion( 3001 D.getDeclSpec().getSourceRange().getBegin(), 3002 "template<> "); 3003 isFunctionTemplateSpecialization = true; 3004 } 3005 } 3006 3007 if (isFunctionTemplateSpecialization) { 3008 if (CheckFunctionTemplateSpecialization(NewFD, 3009 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3010 Previous)) 3011 NewFD->setInvalidDecl(); 3012 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3013 CheckMemberSpecialization(NewFD, Previous)) 3014 NewFD->setInvalidDecl(); 3015 3016 // Perform semantic checking on the function declaration. 3017 bool OverloadableAttrRequired = false; // FIXME: HACK! 3018 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3019 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3020 3021 assert((NewFD->isInvalidDecl() || !Redeclaration || 3022 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3023 "previous declaration set still overloaded"); 3024 3025 // If we have a function template, check the template parameter 3026 // list. This will check and merge default template arguments. 3027 if (FunctionTemplate) { 3028 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3029 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3030 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3031 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3032 : TPC_FunctionTemplate); 3033 } 3034 3035 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3036 // An out-of-line member function declaration must also be a 3037 // definition (C++ [dcl.meaning]p1). 3038 // Note that this is not the case for explicit specializations of 3039 // function templates or member functions of class templates, per 3040 // C++ [temp.expl.spec]p2. 3041 if (!IsFunctionDefinition && !isFriend && 3042 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3043 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3044 << D.getCXXScopeSpec().getRange(); 3045 NewFD->setInvalidDecl(); 3046 } else if (!Redeclaration) { 3047 // The user tried to provide an out-of-line definition for a 3048 // function that is a member of a class or namespace, but there 3049 // was no such member function declared (C++ [class.mfct]p2, 3050 // C++ [namespace.memdef]p2). For example: 3051 // 3052 // class X { 3053 // void f() const; 3054 // }; 3055 // 3056 // void X::f() { } // ill-formed 3057 // 3058 // Complain about this problem, and attempt to suggest close 3059 // matches (e.g., those that differ only in cv-qualifiers and 3060 // whether the parameter types are references). 3061 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3062 << Name << DC << D.getCXXScopeSpec().getRange(); 3063 NewFD->setInvalidDecl(); 3064 3065 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3066 ForRedeclaration); 3067 LookupQualifiedName(Prev, DC); 3068 assert(!Prev.isAmbiguous() && 3069 "Cannot have an ambiguity in previous-declaration lookup"); 3070 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3071 Func != FuncEnd; ++Func) { 3072 if (isa<FunctionDecl>(*Func) && 3073 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3074 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3075 } 3076 } 3077 } 3078 3079 // Handle attributes. We need to have merged decls when handling attributes 3080 // (for example to check for conflicts, etc). 3081 // FIXME: This needs to happen before we merge declarations. Then, 3082 // let attribute merging cope with attribute conflicts. 3083 ProcessDeclAttributes(S, NewFD, D); 3084 3085 // attributes declared post-definition are currently ignored 3086 if (Redeclaration && Previous.isSingleResult()) { 3087 const FunctionDecl *Def; 3088 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3089 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3090 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3091 Diag(Def->getLocation(), diag::note_previous_definition); 3092 } 3093 } 3094 3095 AddKnownFunctionAttributes(NewFD); 3096 3097 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3098 // If a function name is overloadable in C, then every function 3099 // with that name must be marked "overloadable". 3100 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3101 << Redeclaration << NewFD; 3102 if (!Previous.empty()) 3103 Diag(Previous.getRepresentativeDecl()->getLocation(), 3104 diag::note_attribute_overloadable_prev_overload); 3105 NewFD->addAttr(::new (Context) OverloadableAttr()); 3106 } 3107 3108 // If this is a locally-scoped extern C function, update the 3109 // map of such names. 3110 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3111 && !NewFD->isInvalidDecl()) 3112 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3113 3114 // Set this FunctionDecl's range up to the right paren. 3115 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3116 3117 if (FunctionTemplate && NewFD->isInvalidDecl()) 3118 FunctionTemplate->setInvalidDecl(); 3119 3120 if (FunctionTemplate) 3121 return FunctionTemplate; 3122 3123 return NewFD; 3124} 3125 3126/// \brief Perform semantic checking of a new function declaration. 3127/// 3128/// Performs semantic analysis of the new function declaration 3129/// NewFD. This routine performs all semantic checking that does not 3130/// require the actual declarator involved in the declaration, and is 3131/// used both for the declaration of functions as they are parsed 3132/// (called via ActOnDeclarator) and for the declaration of functions 3133/// that have been instantiated via C++ template instantiation (called 3134/// via InstantiateDecl). 3135/// 3136/// \param IsExplicitSpecialiation whether this new function declaration is 3137/// an explicit specialization of the previous declaration. 3138/// 3139/// This sets NewFD->isInvalidDecl() to true if there was an error. 3140void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3141 LookupResult &Previous, 3142 bool IsExplicitSpecialization, 3143 bool &Redeclaration, 3144 bool &OverloadableAttrRequired) { 3145 // If NewFD is already known erroneous, don't do any of this checking. 3146 if (NewFD->isInvalidDecl()) 3147 return; 3148 3149 if (NewFD->getResultType()->isVariablyModifiedType()) { 3150 // Functions returning a variably modified type violate C99 6.7.5.2p2 3151 // because all functions have linkage. 3152 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3153 return NewFD->setInvalidDecl(); 3154 } 3155 3156 if (NewFD->isMain()) 3157 CheckMain(NewFD); 3158 3159 // Check for a previous declaration of this name. 3160 if (Previous.empty() && NewFD->isExternC()) { 3161 // Since we did not find anything by this name and we're declaring 3162 // an extern "C" function, look for a non-visible extern "C" 3163 // declaration with the same name. 3164 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3165 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3166 if (Pos != LocallyScopedExternalDecls.end()) 3167 Previous.addDecl(Pos->second); 3168 } 3169 3170 // Merge or overload the declaration with an existing declaration of 3171 // the same name, if appropriate. 3172 if (!Previous.empty()) { 3173 // Determine whether NewFD is an overload of PrevDecl or 3174 // a declaration that requires merging. If it's an overload, 3175 // there's no more work to do here; we'll just add the new 3176 // function to the scope. 3177 3178 NamedDecl *OldDecl = 0; 3179 if (!AllowOverloadingOfFunction(Previous, Context)) { 3180 Redeclaration = true; 3181 OldDecl = Previous.getFoundDecl(); 3182 } else { 3183 if (!getLangOptions().CPlusPlus) { 3184 OverloadableAttrRequired = true; 3185 3186 // Functions marked "overloadable" must have a prototype (that 3187 // we can't get through declaration merging). 3188 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3189 Diag(NewFD->getLocation(), 3190 diag::err_attribute_overloadable_no_prototype) 3191 << NewFD; 3192 Redeclaration = true; 3193 3194 // Turn this into a variadic function with no parameters. 3195 QualType R = Context.getFunctionType( 3196 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3197 0, 0, true, 0); 3198 NewFD->setType(R); 3199 return NewFD->setInvalidDecl(); 3200 } 3201 } 3202 3203 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3204 case Ovl_Match: 3205 Redeclaration = true; 3206 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3207 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3208 Redeclaration = false; 3209 } 3210 break; 3211 3212 case Ovl_NonFunction: 3213 Redeclaration = true; 3214 break; 3215 3216 case Ovl_Overload: 3217 Redeclaration = false; 3218 break; 3219 } 3220 } 3221 3222 if (Redeclaration) { 3223 // NewFD and OldDecl represent declarations that need to be 3224 // merged. 3225 if (MergeFunctionDecl(NewFD, OldDecl)) 3226 return NewFD->setInvalidDecl(); 3227 3228 Previous.clear(); 3229 Previous.addDecl(OldDecl); 3230 3231 if (FunctionTemplateDecl *OldTemplateDecl 3232 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3233 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3234 FunctionTemplateDecl *NewTemplateDecl 3235 = NewFD->getDescribedFunctionTemplate(); 3236 assert(NewTemplateDecl && "Template/non-template mismatch"); 3237 if (CXXMethodDecl *Method 3238 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3239 Method->setAccess(OldTemplateDecl->getAccess()); 3240 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3241 } 3242 3243 // If this is an explicit specialization of a member that is a function 3244 // template, mark it as a member specialization. 3245 if (IsExplicitSpecialization && 3246 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3247 NewTemplateDecl->setMemberSpecialization(); 3248 assert(OldTemplateDecl->isMemberSpecialization()); 3249 } 3250 } else { 3251 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3252 NewFD->setAccess(OldDecl->getAccess()); 3253 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3254 } 3255 } 3256 } 3257 3258 // Semantic checking for this function declaration (in isolation). 3259 if (getLangOptions().CPlusPlus) { 3260 // C++-specific checks. 3261 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3262 CheckConstructor(Constructor); 3263 } else if (CXXDestructorDecl *Destructor = 3264 dyn_cast<CXXDestructorDecl>(NewFD)) { 3265 CXXRecordDecl *Record = Destructor->getParent(); 3266 QualType ClassType = Context.getTypeDeclType(Record); 3267 3268 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3269 // type is dependent? Both gcc and edg can handle that. 3270 if (!ClassType->isDependentType()) { 3271 DeclarationName Name 3272 = Context.DeclarationNames.getCXXDestructorName( 3273 Context.getCanonicalType(ClassType)); 3274 if (NewFD->getDeclName() != Name) { 3275 Diag(NewFD->getLocation(), diag::err_destructor_name); 3276 return NewFD->setInvalidDecl(); 3277 } 3278 } 3279 3280 Record->setUserDeclaredDestructor(true); 3281 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3282 // user-defined destructor. 3283 Record->setPOD(false); 3284 3285 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3286 // declared destructor. 3287 // FIXME: C++0x: don't do this for "= default" destructors 3288 Record->setHasTrivialDestructor(false); 3289 } else if (CXXConversionDecl *Conversion 3290 = dyn_cast<CXXConversionDecl>(NewFD)) { 3291 ActOnConversionDeclarator(Conversion); 3292 } 3293 3294 // Find any virtual functions that this function overrides. 3295 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3296 if (!Method->isFunctionTemplateSpecialization() && 3297 !Method->getDescribedFunctionTemplate()) 3298 AddOverriddenMethods(Method->getParent(), Method); 3299 } 3300 3301 // Additional checks for the destructor; make sure we do this after we 3302 // figure out whether the destructor is virtual. 3303 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3304 if (!Destructor->getParent()->isDependentType()) 3305 CheckDestructor(Destructor); 3306 3307 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3308 if (NewFD->isOverloadedOperator() && 3309 CheckOverloadedOperatorDeclaration(NewFD)) 3310 return NewFD->setInvalidDecl(); 3311 3312 // In C++, check default arguments now that we have merged decls. Unless 3313 // the lexical context is the class, because in this case this is done 3314 // during delayed parsing anyway. 3315 if (!CurContext->isRecord()) 3316 CheckCXXDefaultArguments(NewFD); 3317 } 3318} 3319 3320void Sema::CheckMain(FunctionDecl* FD) { 3321 // C++ [basic.start.main]p3: A program that declares main to be inline 3322 // or static is ill-formed. 3323 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3324 // shall not appear in a declaration of main. 3325 // static main is not an error under C99, but we should warn about it. 3326 bool isInline = FD->isInlineSpecified(); 3327 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3328 if (isInline || isStatic) { 3329 unsigned diagID = diag::warn_unusual_main_decl; 3330 if (isInline || getLangOptions().CPlusPlus) 3331 diagID = diag::err_unusual_main_decl; 3332 3333 int which = isStatic + (isInline << 1) - 1; 3334 Diag(FD->getLocation(), diagID) << which; 3335 } 3336 3337 QualType T = FD->getType(); 3338 assert(T->isFunctionType() && "function decl is not of function type"); 3339 const FunctionType* FT = T->getAs<FunctionType>(); 3340 3341 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3342 // TODO: add a replacement fixit to turn the return type into 'int'. 3343 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3344 FD->setInvalidDecl(true); 3345 } 3346 3347 // Treat protoless main() as nullary. 3348 if (isa<FunctionNoProtoType>(FT)) return; 3349 3350 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3351 unsigned nparams = FTP->getNumArgs(); 3352 assert(FD->getNumParams() == nparams); 3353 3354 if (nparams > 3) { 3355 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3356 FD->setInvalidDecl(true); 3357 nparams = 3; 3358 } 3359 3360 // FIXME: a lot of the following diagnostics would be improved 3361 // if we had some location information about types. 3362 3363 QualType CharPP = 3364 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3365 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3366 3367 for (unsigned i = 0; i < nparams; ++i) { 3368 QualType AT = FTP->getArgType(i); 3369 3370 bool mismatch = true; 3371 3372 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3373 mismatch = false; 3374 else if (Expected[i] == CharPP) { 3375 // As an extension, the following forms are okay: 3376 // char const ** 3377 // char const * const * 3378 // char * const * 3379 3380 QualifierCollector qs; 3381 const PointerType* PT; 3382 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3383 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3384 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3385 qs.removeConst(); 3386 mismatch = !qs.empty(); 3387 } 3388 } 3389 3390 if (mismatch) { 3391 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3392 // TODO: suggest replacing given type with expected type 3393 FD->setInvalidDecl(true); 3394 } 3395 } 3396 3397 if (nparams == 1 && !FD->isInvalidDecl()) { 3398 Diag(FD->getLocation(), diag::warn_main_one_arg); 3399 } 3400} 3401 3402bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3403 // FIXME: Need strict checking. In C89, we need to check for 3404 // any assignment, increment, decrement, function-calls, or 3405 // commas outside of a sizeof. In C99, it's the same list, 3406 // except that the aforementioned are allowed in unevaluated 3407 // expressions. Everything else falls under the 3408 // "may accept other forms of constant expressions" exception. 3409 // (We never end up here for C++, so the constant expression 3410 // rules there don't matter.) 3411 if (Init->isConstantInitializer(Context)) 3412 return false; 3413 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3414 << Init->getSourceRange(); 3415 return true; 3416} 3417 3418void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3419 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3420} 3421 3422/// AddInitializerToDecl - Adds the initializer Init to the 3423/// declaration dcl. If DirectInit is true, this is C++ direct 3424/// initialization rather than copy initialization. 3425void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3426 Decl *RealDecl = dcl.getAs<Decl>(); 3427 // If there is no declaration, there was an error parsing it. Just ignore 3428 // the initializer. 3429 if (RealDecl == 0) 3430 return; 3431 3432 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3433 // With declarators parsed the way they are, the parser cannot 3434 // distinguish between a normal initializer and a pure-specifier. 3435 // Thus this grotesque test. 3436 IntegerLiteral *IL; 3437 Expr *Init = static_cast<Expr *>(init.get()); 3438 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3439 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3440 CheckPureMethod(Method, Init->getSourceRange()); 3441 else { 3442 Diag(Method->getLocation(), diag::err_member_function_initialization) 3443 << Method->getDeclName() << Init->getSourceRange(); 3444 Method->setInvalidDecl(); 3445 } 3446 return; 3447 } 3448 3449 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3450 if (!VDecl) { 3451 if (getLangOptions().CPlusPlus && 3452 RealDecl->getLexicalDeclContext()->isRecord() && 3453 isa<NamedDecl>(RealDecl)) 3454 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3455 << cast<NamedDecl>(RealDecl)->getDeclName(); 3456 else 3457 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3458 RealDecl->setInvalidDecl(); 3459 return; 3460 } 3461 3462 // A definition must end up with a complete type, which means it must be 3463 // complete with the restriction that an array type might be completed by the 3464 // initializer; note that later code assumes this restriction. 3465 QualType BaseDeclType = VDecl->getType(); 3466 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3467 BaseDeclType = Array->getElementType(); 3468 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3469 diag::err_typecheck_decl_incomplete_type)) { 3470 RealDecl->setInvalidDecl(); 3471 return; 3472 } 3473 3474 // The variable can not have an abstract class type. 3475 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3476 diag::err_abstract_type_in_decl, 3477 AbstractVariableType)) 3478 VDecl->setInvalidDecl(); 3479 3480 const VarDecl *Def = 0; 3481 if (VDecl->getDefinition(Def)) { 3482 Diag(VDecl->getLocation(), diag::err_redefinition) 3483 << VDecl->getDeclName(); 3484 Diag(Def->getLocation(), diag::note_previous_definition); 3485 VDecl->setInvalidDecl(); 3486 return; 3487 } 3488 3489 // Take ownership of the expression, now that we're sure we have somewhere 3490 // to put it. 3491 Expr *Init = init.takeAs<Expr>(); 3492 assert(Init && "missing initializer"); 3493 3494 // Get the decls type and save a reference for later, since 3495 // CheckInitializerTypes may change it. 3496 QualType DclT = VDecl->getType(), SavT = DclT; 3497 if (VDecl->isBlockVarDecl()) { 3498 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3499 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3500 VDecl->setInvalidDecl(); 3501 } else if (!VDecl->isInvalidDecl()) { 3502 if (VDecl->getType()->isReferenceType()) { 3503 InitializedEntity Entity 3504 = InitializedEntity::InitializeVariable(VDecl); 3505 3506 // FIXME: Poor source location information. 3507 InitializationKind Kind 3508 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3509 SourceLocation(), 3510 SourceLocation()) 3511 : InitializationKind::CreateCopy(VDecl->getLocation(), 3512 SourceLocation()); 3513 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3514 if (InitSeq) { 3515 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3516 MultiExprArg(*this, (void**)&Init, 1)); 3517 if (Result.isInvalid()) { 3518 VDecl->setInvalidDecl(); 3519 return; 3520 } 3521 3522 Init = Result.takeAs<Expr>(); 3523 } else { 3524 InitSeq.Diagnose(*this, Entity, Kind, &Init, 1); 3525 VDecl->setInvalidDecl(); 3526 return; 3527 } 3528 3529 } else if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3530 VDecl->getDeclName(), DirectInit)) 3531 VDecl->setInvalidDecl(); 3532 3533 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3534 // Don't check invalid declarations to avoid emitting useless diagnostics. 3535 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3536 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3537 CheckForConstantInitializer(Init, DclT); 3538 } 3539 } 3540 } else if (VDecl->isStaticDataMember() && 3541 VDecl->getLexicalDeclContext()->isRecord()) { 3542 // This is an in-class initialization for a static data member, e.g., 3543 // 3544 // struct S { 3545 // static const int value = 17; 3546 // }; 3547 3548 // Attach the initializer 3549 VDecl->setInit(Context, Init); 3550 3551 // C++ [class.mem]p4: 3552 // A member-declarator can contain a constant-initializer only 3553 // if it declares a static member (9.4) of const integral or 3554 // const enumeration type, see 9.4.2. 3555 QualType T = VDecl->getType(); 3556 if (!T->isDependentType() && 3557 (!Context.getCanonicalType(T).isConstQualified() || 3558 !T->isIntegralType())) { 3559 Diag(VDecl->getLocation(), diag::err_member_initialization) 3560 << VDecl->getDeclName() << Init->getSourceRange(); 3561 VDecl->setInvalidDecl(); 3562 } else { 3563 // C++ [class.static.data]p4: 3564 // If a static data member is of const integral or const 3565 // enumeration type, its declaration in the class definition 3566 // can specify a constant-initializer which shall be an 3567 // integral constant expression (5.19). 3568 if (!Init->isTypeDependent() && 3569 !Init->getType()->isIntegralType()) { 3570 // We have a non-dependent, non-integral or enumeration type. 3571 Diag(Init->getSourceRange().getBegin(), 3572 diag::err_in_class_initializer_non_integral_type) 3573 << Init->getType() << Init->getSourceRange(); 3574 VDecl->setInvalidDecl(); 3575 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3576 // Check whether the expression is a constant expression. 3577 llvm::APSInt Value; 3578 SourceLocation Loc; 3579 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3580 Diag(Loc, diag::err_in_class_initializer_non_constant) 3581 << Init->getSourceRange(); 3582 VDecl->setInvalidDecl(); 3583 } else if (!VDecl->getType()->isDependentType()) 3584 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3585 } 3586 } 3587 } else if (VDecl->isFileVarDecl()) { 3588 if (VDecl->getStorageClass() == VarDecl::Extern) 3589 Diag(VDecl->getLocation(), diag::warn_extern_init); 3590 if (!VDecl->isInvalidDecl()) 3591 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3592 VDecl->getDeclName(), DirectInit)) 3593 VDecl->setInvalidDecl(); 3594 3595 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3596 // Don't check invalid declarations to avoid emitting useless diagnostics. 3597 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3598 // C99 6.7.8p4. All file scoped initializers need to be constant. 3599 CheckForConstantInitializer(Init, DclT); 3600 } 3601 } 3602 // If the type changed, it means we had an incomplete type that was 3603 // completed by the initializer. For example: 3604 // int ary[] = { 1, 3, 5 }; 3605 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3606 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3607 VDecl->setType(DclT); 3608 Init->setType(DclT); 3609 } 3610 3611 Init = MaybeCreateCXXExprWithTemporaries(Init, 3612 /*ShouldDestroyTemporaries=*/true); 3613 // Attach the initializer to the decl. 3614 VDecl->setInit(Context, Init); 3615 3616 // If the previous declaration of VDecl was a tentative definition, 3617 // remove it from the set of tentative definitions. 3618 if (VDecl->getPreviousDeclaration() && 3619 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3620 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3621 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3622 } 3623 3624 return; 3625} 3626 3627void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3628 bool TypeContainsUndeducedAuto) { 3629 Decl *RealDecl = dcl.getAs<Decl>(); 3630 3631 // If there is no declaration, there was an error parsing it. Just ignore it. 3632 if (RealDecl == 0) 3633 return; 3634 3635 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3636 QualType Type = Var->getType(); 3637 3638 // Record tentative definitions. 3639 if (Var->isTentativeDefinition(Context)) { 3640 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3641 InsertPair = 3642 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3643 3644 // Keep the latest definition in the map. If we see 'int i; int i;' we 3645 // want the second one in the map. 3646 InsertPair.first->second = Var; 3647 3648 // However, for the list, we don't care about the order, just make sure 3649 // that there are no dupes for a given declaration name. 3650 if (InsertPair.second) 3651 TentativeDefinitionList.push_back(Var->getDeclName()); 3652 } 3653 3654 // C++ [dcl.init.ref]p3: 3655 // The initializer can be omitted for a reference only in a 3656 // parameter declaration (8.3.5), in the declaration of a 3657 // function return type, in the declaration of a class member 3658 // within its class declaration (9.2), and where the extern 3659 // specifier is explicitly used. 3660 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3661 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3662 << Var->getDeclName() 3663 << SourceRange(Var->getLocation(), Var->getLocation()); 3664 Var->setInvalidDecl(); 3665 return; 3666 } 3667 3668 // C++0x [dcl.spec.auto]p3 3669 if (TypeContainsUndeducedAuto) { 3670 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3671 << Var->getDeclName() << Type; 3672 Var->setInvalidDecl(); 3673 return; 3674 } 3675 3676 // An array without size is an incomplete type, and there are no special 3677 // rules in C++ to make such a definition acceptable. 3678 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3679 !Var->hasExternalStorage()) { 3680 Diag(Var->getLocation(), 3681 diag::err_typecheck_incomplete_array_needs_initializer); 3682 Var->setInvalidDecl(); 3683 return; 3684 } 3685 3686 // C++ [temp.expl.spec]p15: 3687 // An explicit specialization of a static data member of a template is a 3688 // definition if the declaration includes an initializer; otherwise, it 3689 // is a declaration. 3690 if (Var->isStaticDataMember() && 3691 Var->getInstantiatedFromStaticDataMember() && 3692 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3693 return; 3694 3695 // C++ [dcl.init]p9: 3696 // If no initializer is specified for an object, and the object 3697 // is of (possibly cv-qualified) non-POD class type (or array 3698 // thereof), the object shall be default-initialized; if the 3699 // object is of const-qualified type, the underlying class type 3700 // shall have a user-declared default constructor. 3701 // 3702 // FIXME: Diagnose the "user-declared default constructor" bit. 3703 if (getLangOptions().CPlusPlus) { 3704 QualType InitType = Type; 3705 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3706 InitType = Context.getBaseElementType(Array); 3707 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3708 InitType->isRecordType() && !InitType->isDependentType()) { 3709 if (!RequireCompleteType(Var->getLocation(), InitType, 3710 diag::err_invalid_incomplete_type_use)) { 3711 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3712 3713 CXXConstructorDecl *Constructor 3714 = PerformInitializationByConstructor(InitType, 3715 MultiExprArg(*this, 0, 0), 3716 Var->getLocation(), 3717 SourceRange(Var->getLocation(), 3718 Var->getLocation()), 3719 Var->getDeclName(), 3720 InitializationKind::CreateDefault(Var->getLocation()), 3721 ConstructorArgs); 3722 3723 // FIXME: Location info for the variable initialization? 3724 if (!Constructor) 3725 Var->setInvalidDecl(); 3726 else { 3727 // FIXME: Cope with initialization of arrays 3728 if (!Constructor->isTrivial() && 3729 InitializeVarWithConstructor(Var, Constructor, 3730 move_arg(ConstructorArgs))) 3731 Var->setInvalidDecl(); 3732 3733 FinalizeVarWithDestructor(Var, InitType); 3734 } 3735 } else { 3736 Var->setInvalidDecl(); 3737 } 3738 } 3739 3740 // The variable can not have an abstract class type. 3741 if (RequireNonAbstractType(Var->getLocation(), Type, 3742 diag::err_abstract_type_in_decl, 3743 AbstractVariableType)) 3744 Var->setInvalidDecl(); 3745 } 3746 3747#if 0 3748 // FIXME: Temporarily disabled because we are not properly parsing 3749 // linkage specifications on declarations, e.g., 3750 // 3751 // extern "C" const CGPoint CGPointerZero; 3752 // 3753 // C++ [dcl.init]p9: 3754 // 3755 // If no initializer is specified for an object, and the 3756 // object is of (possibly cv-qualified) non-POD class type (or 3757 // array thereof), the object shall be default-initialized; if 3758 // the object is of const-qualified type, the underlying class 3759 // type shall have a user-declared default 3760 // constructor. Otherwise, if no initializer is specified for 3761 // an object, the object and its subobjects, if any, have an 3762 // indeterminate initial value; if the object or any of its 3763 // subobjects are of const-qualified type, the program is 3764 // ill-formed. 3765 // 3766 // This isn't technically an error in C, so we don't diagnose it. 3767 // 3768 // FIXME: Actually perform the POD/user-defined default 3769 // constructor check. 3770 if (getLangOptions().CPlusPlus && 3771 Context.getCanonicalType(Type).isConstQualified() && 3772 !Var->hasExternalStorage()) 3773 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3774 << Var->getName() 3775 << SourceRange(Var->getLocation(), Var->getLocation()); 3776#endif 3777 } 3778} 3779 3780Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3781 DeclPtrTy *Group, 3782 unsigned NumDecls) { 3783 llvm::SmallVector<Decl*, 8> Decls; 3784 3785 if (DS.isTypeSpecOwned()) 3786 Decls.push_back((Decl*)DS.getTypeRep()); 3787 3788 for (unsigned i = 0; i != NumDecls; ++i) 3789 if (Decl *D = Group[i].getAs<Decl>()) 3790 Decls.push_back(D); 3791 3792 // Perform semantic analysis that depends on having fully processed both 3793 // the declarator and initializer. 3794 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3795 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3796 if (!IDecl) 3797 continue; 3798 QualType T = IDecl->getType(); 3799 3800 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3801 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3802 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3803 if (T->isDependentType()) { 3804 // If T is dependent, we should not require a complete type. 3805 // (RequireCompleteType shouldn't be called with dependent types.) 3806 // But we still can at least check if we've got an array of unspecified 3807 // size without an initializer. 3808 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3809 !IDecl->getInit()) { 3810 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3811 << T; 3812 IDecl->setInvalidDecl(); 3813 } 3814 } else if (!IDecl->isInvalidDecl()) { 3815 // If T is an incomplete array type with an initializer list that is 3816 // dependent on something, its size has not been fixed. We could attempt 3817 // to fix the size for such arrays, but we would still have to check 3818 // here for initializers containing a C++0x vararg expansion, e.g. 3819 // template <typename... Args> void f(Args... args) { 3820 // int vals[] = { args }; 3821 // } 3822 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3823 Expr *Init = IDecl->getInit(); 3824 if (IAT && Init && 3825 (Init->isTypeDependent() || Init->isValueDependent())) { 3826 // Check that the member type of the array is complete, at least. 3827 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3828 diag::err_typecheck_decl_incomplete_type)) 3829 IDecl->setInvalidDecl(); 3830 } else if (RequireCompleteType(IDecl->getLocation(), T, 3831 diag::err_typecheck_decl_incomplete_type)) 3832 IDecl->setInvalidDecl(); 3833 } 3834 } 3835 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3836 // object that has file scope without an initializer, and without a 3837 // storage-class specifier or with the storage-class specifier "static", 3838 // constitutes a tentative definition. Note: A tentative definition with 3839 // external linkage is valid (C99 6.2.2p5). 3840 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3841 if (const IncompleteArrayType *ArrayT 3842 = Context.getAsIncompleteArrayType(T)) { 3843 if (RequireCompleteType(IDecl->getLocation(), 3844 ArrayT->getElementType(), 3845 diag::err_illegal_decl_array_incomplete_type)) 3846 IDecl->setInvalidDecl(); 3847 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3848 // C99 6.9.2p3: If the declaration of an identifier for an object is 3849 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3850 // declared type shall not be an incomplete type. 3851 // NOTE: code such as the following 3852 // static struct s; 3853 // struct s { int a; }; 3854 // is accepted by gcc. Hence here we issue a warning instead of 3855 // an error and we do not invalidate the static declaration. 3856 // NOTE: to avoid multiple warnings, only check the first declaration. 3857 if (IDecl->getPreviousDeclaration() == 0) 3858 RequireCompleteType(IDecl->getLocation(), T, 3859 diag::ext_typecheck_decl_incomplete_type); 3860 } 3861 } 3862 } 3863 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3864 Decls.data(), Decls.size())); 3865} 3866 3867 3868/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3869/// to introduce parameters into function prototype scope. 3870Sema::DeclPtrTy 3871Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3872 const DeclSpec &DS = D.getDeclSpec(); 3873 3874 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3875 VarDecl::StorageClass StorageClass = VarDecl::None; 3876 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3877 StorageClass = VarDecl::Register; 3878 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3879 Diag(DS.getStorageClassSpecLoc(), 3880 diag::err_invalid_storage_class_in_func_decl); 3881 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3882 } 3883 3884 if (D.getDeclSpec().isThreadSpecified()) 3885 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3886 3887 DiagnoseFunctionSpecifiers(D); 3888 3889 // Check that there are no default arguments inside the type of this 3890 // parameter (C++ only). 3891 if (getLangOptions().CPlusPlus) 3892 CheckExtraCXXDefaultArguments(D); 3893 3894 TypeSourceInfo *TInfo = 0; 3895 TagDecl *OwnedDecl = 0; 3896 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3897 3898 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3899 // C++ [dcl.fct]p6: 3900 // Types shall not be defined in return or parameter types. 3901 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3902 << Context.getTypeDeclType(OwnedDecl); 3903 } 3904 3905 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3906 // Can this happen for params? We already checked that they don't conflict 3907 // among each other. Here they can only shadow globals, which is ok. 3908 IdentifierInfo *II = D.getIdentifier(); 3909 if (II) { 3910 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3911 if (PrevDecl->isTemplateParameter()) { 3912 // Maybe we will complain about the shadowed template parameter. 3913 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3914 // Just pretend that we didn't see the previous declaration. 3915 PrevDecl = 0; 3916 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3917 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3918 3919 // Recover by removing the name 3920 II = 0; 3921 D.SetIdentifier(0, D.getIdentifierLoc()); 3922 } 3923 } 3924 } 3925 3926 // Parameters can not be abstract class types. 3927 // For record types, this is done by the AbstractClassUsageDiagnoser once 3928 // the class has been completely parsed. 3929 if (!CurContext->isRecord() && 3930 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3931 diag::err_abstract_type_in_decl, 3932 AbstractParamType)) 3933 D.setInvalidType(true); 3934 3935 QualType T = adjustParameterType(parmDeclType); 3936 3937 ParmVarDecl *New 3938 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3939 T, TInfo, StorageClass, 0); 3940 3941 if (D.isInvalidType()) 3942 New->setInvalidDecl(); 3943 3944 // Parameter declarators cannot be interface types. All ObjC objects are 3945 // passed by reference. 3946 if (T->isObjCInterfaceType()) { 3947 Diag(D.getIdentifierLoc(), 3948 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3949 New->setInvalidDecl(); 3950 } 3951 3952 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3953 if (D.getCXXScopeSpec().isSet()) { 3954 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3955 << D.getCXXScopeSpec().getRange(); 3956 New->setInvalidDecl(); 3957 } 3958 3959 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3960 // duration shall not be qualified by an address-space qualifier." 3961 // Since all parameters have automatic store duration, they can not have 3962 // an address space. 3963 if (T.getAddressSpace() != 0) { 3964 Diag(D.getIdentifierLoc(), 3965 diag::err_arg_with_address_space); 3966 New->setInvalidDecl(); 3967 } 3968 3969 3970 // Add the parameter declaration into this scope. 3971 S->AddDecl(DeclPtrTy::make(New)); 3972 if (II) 3973 IdResolver.AddDecl(New); 3974 3975 ProcessDeclAttributes(S, New, D); 3976 3977 if (New->hasAttr<BlocksAttr>()) { 3978 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3979 } 3980 return DeclPtrTy::make(New); 3981} 3982 3983void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3984 SourceLocation LocAfterDecls) { 3985 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3986 "Not a function declarator!"); 3987 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3988 3989 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3990 // for a K&R function. 3991 if (!FTI.hasPrototype) { 3992 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3993 --i; 3994 if (FTI.ArgInfo[i].Param == 0) { 3995 llvm::SmallString<256> Code; 3996 llvm::raw_svector_ostream(Code) << " int " 3997 << FTI.ArgInfo[i].Ident->getName() 3998 << ";\n"; 3999 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4000 << FTI.ArgInfo[i].Ident 4001 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4002 4003 // Implicitly declare the argument as type 'int' for lack of a better 4004 // type. 4005 DeclSpec DS; 4006 const char* PrevSpec; // unused 4007 unsigned DiagID; // unused 4008 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4009 PrevSpec, DiagID); 4010 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4011 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4012 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4013 } 4014 } 4015 } 4016} 4017 4018Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4019 Declarator &D) { 4020 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4021 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4022 "Not a function declarator!"); 4023 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4024 4025 if (FTI.hasPrototype) { 4026 // FIXME: Diagnose arguments without names in C. 4027 } 4028 4029 Scope *ParentScope = FnBodyScope->getParent(); 4030 4031 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4032 MultiTemplateParamsArg(*this), 4033 /*IsFunctionDefinition=*/true); 4034 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4035} 4036 4037static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4038 // Don't warn about invalid declarations. 4039 if (FD->isInvalidDecl()) 4040 return false; 4041 4042 // Or declarations that aren't global. 4043 if (!FD->isGlobal()) 4044 return false; 4045 4046 // Don't warn about C++ member functions. 4047 if (isa<CXXMethodDecl>(FD)) 4048 return false; 4049 4050 // Don't warn about 'main'. 4051 if (FD->isMain()) 4052 return false; 4053 4054 // Don't warn about inline functions. 4055 if (FD->isInlineSpecified()) 4056 return false; 4057 4058 // Don't warn about function templates. 4059 if (FD->getDescribedFunctionTemplate()) 4060 return false; 4061 4062 // Don't warn about function template specializations. 4063 if (FD->isFunctionTemplateSpecialization()) 4064 return false; 4065 4066 bool MissingPrototype = true; 4067 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4068 Prev; Prev = Prev->getPreviousDeclaration()) { 4069 // Ignore any declarations that occur in function or method 4070 // scope, because they aren't visible from the header. 4071 if (Prev->getDeclContext()->isFunctionOrMethod()) 4072 continue; 4073 4074 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4075 break; 4076 } 4077 4078 return MissingPrototype; 4079} 4080 4081Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4082 // Clear the last template instantiation error context. 4083 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4084 4085 if (!D) 4086 return D; 4087 FunctionDecl *FD = 0; 4088 4089 if (FunctionTemplateDecl *FunTmpl 4090 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4091 FD = FunTmpl->getTemplatedDecl(); 4092 else 4093 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4094 4095 CurFunctionNeedsScopeChecking = false; 4096 4097 // See if this is a redefinition. 4098 const FunctionDecl *Definition; 4099 if (FD->getBody(Definition)) { 4100 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4101 Diag(Definition->getLocation(), diag::note_previous_definition); 4102 } 4103 4104 // Builtin functions cannot be defined. 4105 if (unsigned BuiltinID = FD->getBuiltinID()) { 4106 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4107 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4108 FD->setInvalidDecl(); 4109 } 4110 } 4111 4112 // The return type of a function definition must be complete 4113 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4114 QualType ResultType = FD->getResultType(); 4115 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4116 !FD->isInvalidDecl() && 4117 RequireCompleteType(FD->getLocation(), ResultType, 4118 diag::err_func_def_incomplete_result)) 4119 FD->setInvalidDecl(); 4120 4121 // GNU warning -Wmissing-prototypes: 4122 // Warn if a global function is defined without a previous 4123 // prototype declaration. This warning is issued even if the 4124 // definition itself provides a prototype. The aim is to detect 4125 // global functions that fail to be declared in header files. 4126 if (ShouldWarnAboutMissingPrototype(FD)) 4127 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4128 4129 if (FnBodyScope) 4130 PushDeclContext(FnBodyScope, FD); 4131 4132 // Check the validity of our function parameters 4133 CheckParmsForFunctionDef(FD); 4134 4135 // Introduce our parameters into the function scope 4136 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4137 ParmVarDecl *Param = FD->getParamDecl(p); 4138 Param->setOwningFunction(FD); 4139 4140 // If this has an identifier, add it to the scope stack. 4141 if (Param->getIdentifier() && FnBodyScope) 4142 PushOnScopeChains(Param, FnBodyScope); 4143 } 4144 4145 // Checking attributes of current function definition 4146 // dllimport attribute. 4147 if (FD->getAttr<DLLImportAttr>() && 4148 (!FD->getAttr<DLLExportAttr>())) { 4149 // dllimport attribute cannot be applied to definition. 4150 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4151 Diag(FD->getLocation(), 4152 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4153 << "dllimport"; 4154 FD->setInvalidDecl(); 4155 return DeclPtrTy::make(FD); 4156 } else { 4157 // If a symbol previously declared dllimport is later defined, the 4158 // attribute is ignored in subsequent references, and a warning is 4159 // emitted. 4160 Diag(FD->getLocation(), 4161 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4162 << FD->getNameAsCString() << "dllimport"; 4163 } 4164 } 4165 return DeclPtrTy::make(FD); 4166} 4167 4168Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4169 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4170} 4171 4172Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4173 bool IsInstantiation) { 4174 Decl *dcl = D.getAs<Decl>(); 4175 Stmt *Body = BodyArg.takeAs<Stmt>(); 4176 4177 FunctionDecl *FD = 0; 4178 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4179 if (FunTmpl) 4180 FD = FunTmpl->getTemplatedDecl(); 4181 else 4182 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4183 4184 if (FD) { 4185 FD->setBody(Body); 4186 if (FD->isMain()) 4187 // C and C++ allow for main to automagically return 0. 4188 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4189 FD->setHasImplicitReturnZero(true); 4190 else 4191 CheckFallThroughForFunctionDef(FD, Body); 4192 4193 if (!FD->isInvalidDecl()) 4194 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4195 4196 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4197 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4198 4199 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4200 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4201 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4202 MD->setBody(Body); 4203 CheckFallThroughForFunctionDef(MD, Body); 4204 MD->setEndLoc(Body->getLocEnd()); 4205 4206 if (!MD->isInvalidDecl()) 4207 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4208 } else { 4209 Body->Destroy(Context); 4210 return DeclPtrTy(); 4211 } 4212 if (!IsInstantiation) 4213 PopDeclContext(); 4214 4215 // Verify and clean out per-function state. 4216 4217 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4218 4219 // Check goto/label use. 4220 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4221 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4222 LabelStmt *L = I->second; 4223 4224 // Verify that we have no forward references left. If so, there was a goto 4225 // or address of a label taken, but no definition of it. Label fwd 4226 // definitions are indicated with a null substmt. 4227 if (L->getSubStmt() != 0) 4228 continue; 4229 4230 // Emit error. 4231 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4232 4233 // At this point, we have gotos that use the bogus label. Stitch it into 4234 // the function body so that they aren't leaked and that the AST is well 4235 // formed. 4236 if (Body == 0) { 4237 // The whole function wasn't parsed correctly, just delete this. 4238 L->Destroy(Context); 4239 continue; 4240 } 4241 4242 // Otherwise, the body is valid: we want to stitch the label decl into the 4243 // function somewhere so that it is properly owned and so that the goto 4244 // has a valid target. Do this by creating a new compound stmt with the 4245 // label in it. 4246 4247 // Give the label a sub-statement. 4248 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4249 4250 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4251 cast<CXXTryStmt>(Body)->getTryBlock() : 4252 cast<CompoundStmt>(Body); 4253 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4254 Elements.push_back(L); 4255 Compound->setStmts(Context, &Elements[0], Elements.size()); 4256 } 4257 FunctionLabelMap.clear(); 4258 4259 if (!Body) return D; 4260 4261 // Verify that that gotos and switch cases don't jump into scopes illegally. 4262 if (CurFunctionNeedsScopeChecking) 4263 DiagnoseInvalidJumps(Body); 4264 4265 // C++ constructors that have function-try-blocks can't have return 4266 // statements in the handlers of that block. (C++ [except.handle]p14) 4267 // Verify this. 4268 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4269 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4270 4271 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4272 MarkBaseAndMemberDestructorsReferenced(Destructor); 4273 4274 // If any errors have occurred, clear out any temporaries that may have 4275 // been leftover. This ensures that these temporaries won't be picked up for 4276 // deletion in some later function. 4277 if (PP.getDiagnostics().hasErrorOccurred()) 4278 ExprTemporaries.clear(); 4279 4280 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4281 return D; 4282} 4283 4284/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4285/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4286NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4287 IdentifierInfo &II, Scope *S) { 4288 // Before we produce a declaration for an implicitly defined 4289 // function, see whether there was a locally-scoped declaration of 4290 // this name as a function or variable. If so, use that 4291 // (non-visible) declaration, and complain about it. 4292 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4293 = LocallyScopedExternalDecls.find(&II); 4294 if (Pos != LocallyScopedExternalDecls.end()) { 4295 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4296 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4297 return Pos->second; 4298 } 4299 4300 // Extension in C99. Legal in C90, but warn about it. 4301 if (II.getName().startswith("__builtin_")) 4302 Diag(Loc, diag::warn_builtin_unknown) << &II; 4303 else if (getLangOptions().C99) 4304 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4305 else 4306 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4307 4308 // Set a Declarator for the implicit definition: int foo(); 4309 const char *Dummy; 4310 DeclSpec DS; 4311 unsigned DiagID; 4312 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4313 Error = Error; // Silence warning. 4314 assert(!Error && "Error setting up implicit decl!"); 4315 Declarator D(DS, Declarator::BlockContext); 4316 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4317 0, 0, false, SourceLocation(), 4318 false, 0,0,0, Loc, Loc, D), 4319 SourceLocation()); 4320 D.SetIdentifier(&II, Loc); 4321 4322 // Insert this function into translation-unit scope. 4323 4324 DeclContext *PrevDC = CurContext; 4325 CurContext = Context.getTranslationUnitDecl(); 4326 4327 FunctionDecl *FD = 4328 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4329 FD->setImplicit(); 4330 4331 CurContext = PrevDC; 4332 4333 AddKnownFunctionAttributes(FD); 4334 4335 return FD; 4336} 4337 4338/// \brief Adds any function attributes that we know a priori based on 4339/// the declaration of this function. 4340/// 4341/// These attributes can apply both to implicitly-declared builtins 4342/// (like __builtin___printf_chk) or to library-declared functions 4343/// like NSLog or printf. 4344void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4345 if (FD->isInvalidDecl()) 4346 return; 4347 4348 // If this is a built-in function, map its builtin attributes to 4349 // actual attributes. 4350 if (unsigned BuiltinID = FD->getBuiltinID()) { 4351 // Handle printf-formatting attributes. 4352 unsigned FormatIdx; 4353 bool HasVAListArg; 4354 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4355 if (!FD->getAttr<FormatAttr>()) 4356 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4357 HasVAListArg ? 0 : FormatIdx + 2)); 4358 } 4359 4360 // Mark const if we don't care about errno and that is the only 4361 // thing preventing the function from being const. This allows 4362 // IRgen to use LLVM intrinsics for such functions. 4363 if (!getLangOptions().MathErrno && 4364 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4365 if (!FD->getAttr<ConstAttr>()) 4366 FD->addAttr(::new (Context) ConstAttr()); 4367 } 4368 4369 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4370 FD->addAttr(::new (Context) NoReturnAttr()); 4371 } 4372 4373 IdentifierInfo *Name = FD->getIdentifier(); 4374 if (!Name) 4375 return; 4376 if ((!getLangOptions().CPlusPlus && 4377 FD->getDeclContext()->isTranslationUnit()) || 4378 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4379 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4380 LinkageSpecDecl::lang_c)) { 4381 // Okay: this could be a libc/libm/Objective-C function we know 4382 // about. 4383 } else 4384 return; 4385 4386 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4387 // FIXME: NSLog and NSLogv should be target specific 4388 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4389 // FIXME: We known better than our headers. 4390 const_cast<FormatAttr *>(Format)->setType("printf"); 4391 } else 4392 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4393 Name->isStr("NSLogv") ? 0 : 2)); 4394 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4395 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4396 // target-specific builtins, perhaps? 4397 if (!FD->getAttr<FormatAttr>()) 4398 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4399 Name->isStr("vasprintf") ? 0 : 3)); 4400 } 4401} 4402 4403TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4404 TypeSourceInfo *TInfo) { 4405 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4406 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4407 4408 if (!TInfo) { 4409 assert(D.isInvalidType() && "no declarator info for valid type"); 4410 TInfo = Context.getTrivialTypeSourceInfo(T); 4411 } 4412 4413 // Scope manipulation handled by caller. 4414 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4415 D.getIdentifierLoc(), 4416 D.getIdentifier(), 4417 TInfo); 4418 4419 if (const TagType *TT = T->getAs<TagType>()) { 4420 TagDecl *TD = TT->getDecl(); 4421 4422 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4423 // keep track of the TypedefDecl. 4424 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4425 TD->setTypedefForAnonDecl(NewTD); 4426 } 4427 4428 if (D.isInvalidType()) 4429 NewTD->setInvalidDecl(); 4430 return NewTD; 4431} 4432 4433 4434/// \brief Determine whether a tag with a given kind is acceptable 4435/// as a redeclaration of the given tag declaration. 4436/// 4437/// \returns true if the new tag kind is acceptable, false otherwise. 4438bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4439 TagDecl::TagKind NewTag, 4440 SourceLocation NewTagLoc, 4441 const IdentifierInfo &Name) { 4442 // C++ [dcl.type.elab]p3: 4443 // The class-key or enum keyword present in the 4444 // elaborated-type-specifier shall agree in kind with the 4445 // declaration to which the name in theelaborated-type-specifier 4446 // refers. This rule also applies to the form of 4447 // elaborated-type-specifier that declares a class-name or 4448 // friend class since it can be construed as referring to the 4449 // definition of the class. Thus, in any 4450 // elaborated-type-specifier, the enum keyword shall be used to 4451 // refer to an enumeration (7.2), the union class-keyshall be 4452 // used to refer to a union (clause 9), and either the class or 4453 // struct class-key shall be used to refer to a class (clause 9) 4454 // declared using the class or struct class-key. 4455 TagDecl::TagKind OldTag = Previous->getTagKind(); 4456 if (OldTag == NewTag) 4457 return true; 4458 4459 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4460 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4461 // Warn about the struct/class tag mismatch. 4462 bool isTemplate = false; 4463 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4464 isTemplate = Record->getDescribedClassTemplate(); 4465 4466 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4467 << (NewTag == TagDecl::TK_class) 4468 << isTemplate << &Name 4469 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4470 OldTag == TagDecl::TK_class? "class" : "struct"); 4471 Diag(Previous->getLocation(), diag::note_previous_use); 4472 return true; 4473 } 4474 return false; 4475} 4476 4477/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4478/// former case, Name will be non-null. In the later case, Name will be null. 4479/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4480/// reference/declaration/definition of a tag. 4481Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4482 SourceLocation KWLoc, const CXXScopeSpec &SS, 4483 IdentifierInfo *Name, SourceLocation NameLoc, 4484 AttributeList *Attr, AccessSpecifier AS, 4485 MultiTemplateParamsArg TemplateParameterLists, 4486 bool &OwnedDecl, bool &IsDependent) { 4487 // If this is not a definition, it must have a name. 4488 assert((Name != 0 || TUK == TUK_Definition) && 4489 "Nameless record must be a definition!"); 4490 4491 OwnedDecl = false; 4492 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4493 4494 // FIXME: Check explicit specializations more carefully. 4495 bool isExplicitSpecialization = false; 4496 if (TUK != TUK_Reference) { 4497 if (TemplateParameterList *TemplateParams 4498 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4499 (TemplateParameterList**)TemplateParameterLists.get(), 4500 TemplateParameterLists.size(), 4501 isExplicitSpecialization)) { 4502 if (TemplateParams->size() > 0) { 4503 // This is a declaration or definition of a class template (which may 4504 // be a member of another template). 4505 OwnedDecl = false; 4506 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4507 SS, Name, NameLoc, Attr, 4508 TemplateParams, 4509 AS); 4510 TemplateParameterLists.release(); 4511 return Result.get(); 4512 } else { 4513 // The "template<>" header is extraneous. 4514 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4515 << ElaboratedType::getNameForTagKind(Kind) << Name; 4516 isExplicitSpecialization = true; 4517 } 4518 } 4519 4520 TemplateParameterLists.release(); 4521 } 4522 4523 DeclContext *SearchDC = CurContext; 4524 DeclContext *DC = CurContext; 4525 bool isStdBadAlloc = false; 4526 bool Invalid = false; 4527 4528 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4529 : NotForRedeclaration); 4530 4531 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4532 4533 if (Name && SS.isNotEmpty()) { 4534 // We have a nested-name tag ('struct foo::bar'). 4535 4536 // Check for invalid 'foo::'. 4537 if (SS.isInvalid()) { 4538 Name = 0; 4539 goto CreateNewDecl; 4540 } 4541 4542 // If this is a friend or a reference to a class in a dependent 4543 // context, don't try to make a decl for it. 4544 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4545 DC = computeDeclContext(SS, false); 4546 if (!DC) { 4547 IsDependent = true; 4548 return DeclPtrTy(); 4549 } 4550 } 4551 4552 if (RequireCompleteDeclContext(SS)) 4553 return DeclPtrTy::make((Decl *)0); 4554 4555 DC = computeDeclContext(SS, true); 4556 SearchDC = DC; 4557 // Look-up name inside 'foo::'. 4558 LookupQualifiedName(Previous, DC); 4559 4560 if (Previous.isAmbiguous()) 4561 return DeclPtrTy(); 4562 4563 // A tag 'foo::bar' must already exist. 4564 if (Previous.empty()) { 4565 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4566 Name = 0; 4567 Invalid = true; 4568 goto CreateNewDecl; 4569 } 4570 } else if (Name) { 4571 // If this is a named struct, check to see if there was a previous forward 4572 // declaration or definition. 4573 // FIXME: We're looking into outer scopes here, even when we 4574 // shouldn't be. Doing so can result in ambiguities that we 4575 // shouldn't be diagnosing. 4576 LookupName(Previous, S); 4577 4578 // Note: there used to be some attempt at recovery here. 4579 if (Previous.isAmbiguous()) 4580 return DeclPtrTy(); 4581 4582 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4583 // FIXME: This makes sure that we ignore the contexts associated 4584 // with C structs, unions, and enums when looking for a matching 4585 // tag declaration or definition. See the similar lookup tweak 4586 // in Sema::LookupName; is there a better way to deal with this? 4587 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4588 SearchDC = SearchDC->getParent(); 4589 } 4590 } 4591 4592 if (Previous.isSingleResult() && 4593 Previous.getFoundDecl()->isTemplateParameter()) { 4594 // Maybe we will complain about the shadowed template parameter. 4595 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4596 // Just pretend that we didn't see the previous declaration. 4597 Previous.clear(); 4598 } 4599 4600 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4601 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4602 // This is a declaration of or a reference to "std::bad_alloc". 4603 isStdBadAlloc = true; 4604 4605 if (Previous.empty() && StdBadAlloc) { 4606 // std::bad_alloc has been implicitly declared (but made invisible to 4607 // name lookup). Fill in this implicit declaration as the previous 4608 // declaration, so that the declarations get chained appropriately. 4609 Previous.addDecl(StdBadAlloc); 4610 } 4611 } 4612 4613 if (!Previous.empty()) { 4614 assert(Previous.isSingleResult()); 4615 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4616 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4617 // If this is a use of a previous tag, or if the tag is already declared 4618 // in the same scope (so that the definition/declaration completes or 4619 // rementions the tag), reuse the decl. 4620 if (TUK == TUK_Reference || TUK == TUK_Friend || 4621 isDeclInScope(PrevDecl, SearchDC, S)) { 4622 // Make sure that this wasn't declared as an enum and now used as a 4623 // struct or something similar. 4624 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4625 bool SafeToContinue 4626 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4627 Kind != TagDecl::TK_enum); 4628 if (SafeToContinue) 4629 Diag(KWLoc, diag::err_use_with_wrong_tag) 4630 << Name 4631 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4632 PrevTagDecl->getKindName()); 4633 else 4634 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4635 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4636 4637 if (SafeToContinue) 4638 Kind = PrevTagDecl->getTagKind(); 4639 else { 4640 // Recover by making this an anonymous redefinition. 4641 Name = 0; 4642 Previous.clear(); 4643 Invalid = true; 4644 } 4645 } 4646 4647 if (!Invalid) { 4648 // If this is a use, just return the declaration we found. 4649 4650 // FIXME: In the future, return a variant or some other clue 4651 // for the consumer of this Decl to know it doesn't own it. 4652 // For our current ASTs this shouldn't be a problem, but will 4653 // need to be changed with DeclGroups. 4654 if (TUK == TUK_Reference || TUK == TUK_Friend) 4655 return DeclPtrTy::make(PrevTagDecl); 4656 4657 // Diagnose attempts to redefine a tag. 4658 if (TUK == TUK_Definition) { 4659 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4660 // If we're defining a specialization and the previous definition 4661 // is from an implicit instantiation, don't emit an error 4662 // here; we'll catch this in the general case below. 4663 if (!isExplicitSpecialization || 4664 !isa<CXXRecordDecl>(Def) || 4665 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4666 == TSK_ExplicitSpecialization) { 4667 Diag(NameLoc, diag::err_redefinition) << Name; 4668 Diag(Def->getLocation(), diag::note_previous_definition); 4669 // If this is a redefinition, recover by making this 4670 // struct be anonymous, which will make any later 4671 // references get the previous definition. 4672 Name = 0; 4673 Previous.clear(); 4674 Invalid = true; 4675 } 4676 } else { 4677 // If the type is currently being defined, complain 4678 // about a nested redefinition. 4679 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4680 if (Tag->isBeingDefined()) { 4681 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4682 Diag(PrevTagDecl->getLocation(), 4683 diag::note_previous_definition); 4684 Name = 0; 4685 Previous.clear(); 4686 Invalid = true; 4687 } 4688 } 4689 4690 // Okay, this is definition of a previously declared or referenced 4691 // tag PrevDecl. We're going to create a new Decl for it. 4692 } 4693 } 4694 // If we get here we have (another) forward declaration or we 4695 // have a definition. Just create a new decl. 4696 4697 } else { 4698 // If we get here, this is a definition of a new tag type in a nested 4699 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4700 // new decl/type. We set PrevDecl to NULL so that the entities 4701 // have distinct types. 4702 Previous.clear(); 4703 } 4704 // If we get here, we're going to create a new Decl. If PrevDecl 4705 // is non-NULL, it's a definition of the tag declared by 4706 // PrevDecl. If it's NULL, we have a new definition. 4707 } else { 4708 // PrevDecl is a namespace, template, or anything else 4709 // that lives in the IDNS_Tag identifier namespace. 4710 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4711 // The tag name clashes with a namespace name, issue an error and 4712 // recover by making this tag be anonymous. 4713 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4714 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4715 Name = 0; 4716 Previous.clear(); 4717 Invalid = true; 4718 } else { 4719 // The existing declaration isn't relevant to us; we're in a 4720 // new scope, so clear out the previous declaration. 4721 Previous.clear(); 4722 } 4723 } 4724 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4725 // C++ [basic.scope.pdecl]p5: 4726 // -- for an elaborated-type-specifier of the form 4727 // 4728 // class-key identifier 4729 // 4730 // if the elaborated-type-specifier is used in the 4731 // decl-specifier-seq or parameter-declaration-clause of a 4732 // function defined in namespace scope, the identifier is 4733 // declared as a class-name in the namespace that contains 4734 // the declaration; otherwise, except as a friend 4735 // declaration, the identifier is declared in the smallest 4736 // non-class, non-function-prototype scope that contains the 4737 // declaration. 4738 // 4739 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4740 // C structs and unions. 4741 // 4742 // It is an error in C++ to declare (rather than define) an enum 4743 // type, including via an elaborated type specifier. We'll 4744 // diagnose that later; for now, declare the enum in the same 4745 // scope as we would have picked for any other tag type. 4746 // 4747 // GNU C also supports this behavior as part of its incomplete 4748 // enum types extension, while GNU C++ does not. 4749 // 4750 // Find the context where we'll be declaring the tag. 4751 // FIXME: We would like to maintain the current DeclContext as the 4752 // lexical context, 4753 while (SearchDC->isRecord()) 4754 SearchDC = SearchDC->getParent(); 4755 4756 // Find the scope where we'll be declaring the tag. 4757 while (S->isClassScope() || 4758 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4759 ((S->getFlags() & Scope::DeclScope) == 0) || 4760 (S->getEntity() && 4761 ((DeclContext *)S->getEntity())->isTransparentContext())) 4762 S = S->getParent(); 4763 4764 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4765 // C++ [namespace.memdef]p3: 4766 // If a friend declaration in a non-local class first declares a 4767 // class or function, the friend class or function is a member of 4768 // the innermost enclosing namespace. 4769 while (!SearchDC->isFileContext()) 4770 SearchDC = SearchDC->getParent(); 4771 4772 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4773 while (S->getEntity() != SearchDC) 4774 S = S->getParent(); 4775 } 4776 4777CreateNewDecl: 4778 4779 TagDecl *PrevDecl = 0; 4780 if (Previous.isSingleResult()) 4781 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4782 4783 // If there is an identifier, use the location of the identifier as the 4784 // location of the decl, otherwise use the location of the struct/union 4785 // keyword. 4786 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4787 4788 // Otherwise, create a new declaration. If there is a previous 4789 // declaration of the same entity, the two will be linked via 4790 // PrevDecl. 4791 TagDecl *New; 4792 4793 if (Kind == TagDecl::TK_enum) { 4794 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4795 // enum X { A, B, C } D; D should chain to X. 4796 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4797 cast_or_null<EnumDecl>(PrevDecl)); 4798 // If this is an undefined enum, warn. 4799 if (TUK != TUK_Definition && !Invalid) { 4800 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4801 : diag::ext_forward_ref_enum; 4802 Diag(Loc, DK); 4803 } 4804 } else { 4805 // struct/union/class 4806 4807 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4808 // struct X { int A; } D; D should chain to X. 4809 if (getLangOptions().CPlusPlus) { 4810 // FIXME: Look for a way to use RecordDecl for simple structs. 4811 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4812 cast_or_null<CXXRecordDecl>(PrevDecl)); 4813 4814 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4815 StdBadAlloc = cast<CXXRecordDecl>(New); 4816 } else 4817 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4818 cast_or_null<RecordDecl>(PrevDecl)); 4819 } 4820 4821 if (Kind != TagDecl::TK_enum) { 4822 // Handle #pragma pack: if the #pragma pack stack has non-default 4823 // alignment, make up a packed attribute for this decl. These 4824 // attributes are checked when the ASTContext lays out the 4825 // structure. 4826 // 4827 // It is important for implementing the correct semantics that this 4828 // happen here (in act on tag decl). The #pragma pack stack is 4829 // maintained as a result of parser callbacks which can occur at 4830 // many points during the parsing of a struct declaration (because 4831 // the #pragma tokens are effectively skipped over during the 4832 // parsing of the struct). 4833 if (unsigned Alignment = getPragmaPackAlignment()) 4834 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4835 } 4836 4837 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4838 // C++ [dcl.typedef]p3: 4839 // [...] Similarly, in a given scope, a class or enumeration 4840 // shall not be declared with the same name as a typedef-name 4841 // that is declared in that scope and refers to a type other 4842 // than the class or enumeration itself. 4843 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4844 ForRedeclaration); 4845 LookupName(Lookup, S); 4846 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4847 NamedDecl *PrevTypedefNamed = PrevTypedef; 4848 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4849 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4850 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4851 Diag(Loc, diag::err_tag_definition_of_typedef) 4852 << Context.getTypeDeclType(New) 4853 << PrevTypedef->getUnderlyingType(); 4854 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4855 Invalid = true; 4856 } 4857 } 4858 4859 // If this is a specialization of a member class (of a class template), 4860 // check the specialization. 4861 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4862 Invalid = true; 4863 4864 if (Invalid) 4865 New->setInvalidDecl(); 4866 4867 if (Attr) 4868 ProcessDeclAttributeList(S, New, Attr); 4869 4870 // If we're declaring or defining a tag in function prototype scope 4871 // in C, note that this type can only be used within the function. 4872 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4873 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4874 4875 // Set the lexical context. If the tag has a C++ scope specifier, the 4876 // lexical context will be different from the semantic context. 4877 New->setLexicalDeclContext(CurContext); 4878 4879 // Mark this as a friend decl if applicable. 4880 if (TUK == TUK_Friend) 4881 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4882 4883 // Set the access specifier. 4884 if (!Invalid && TUK != TUK_Friend) 4885 SetMemberAccessSpecifier(New, PrevDecl, AS); 4886 4887 if (TUK == TUK_Definition) 4888 New->startDefinition(); 4889 4890 // If this has an identifier, add it to the scope stack. 4891 if (TUK == TUK_Friend) { 4892 // We might be replacing an existing declaration in the lookup tables; 4893 // if so, borrow its access specifier. 4894 if (PrevDecl) 4895 New->setAccess(PrevDecl->getAccess()); 4896 4897 // Friend tag decls are visible in fairly strange ways. 4898 if (!CurContext->isDependentContext()) { 4899 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4900 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4901 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4902 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4903 } 4904 } else if (Name) { 4905 S = getNonFieldDeclScope(S); 4906 PushOnScopeChains(New, S); 4907 } else { 4908 CurContext->addDecl(New); 4909 } 4910 4911 // If this is the C FILE type, notify the AST context. 4912 if (IdentifierInfo *II = New->getIdentifier()) 4913 if (!New->isInvalidDecl() && 4914 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4915 II->isStr("FILE")) 4916 Context.setFILEDecl(New); 4917 4918 OwnedDecl = true; 4919 return DeclPtrTy::make(New); 4920} 4921 4922void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4923 AdjustDeclIfTemplate(TagD); 4924 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4925 4926 // Enter the tag context. 4927 PushDeclContext(S, Tag); 4928 4929 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4930 FieldCollector->StartClass(); 4931 4932 if (Record->getIdentifier()) { 4933 // C++ [class]p2: 4934 // [...] The class-name is also inserted into the scope of the 4935 // class itself; this is known as the injected-class-name. For 4936 // purposes of access checking, the injected-class-name is treated 4937 // as if it were a public member name. 4938 CXXRecordDecl *InjectedClassName 4939 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4940 CurContext, Record->getLocation(), 4941 Record->getIdentifier(), 4942 Record->getTagKeywordLoc(), 4943 Record); 4944 InjectedClassName->setImplicit(); 4945 InjectedClassName->setAccess(AS_public); 4946 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4947 InjectedClassName->setDescribedClassTemplate(Template); 4948 PushOnScopeChains(InjectedClassName, S); 4949 assert(InjectedClassName->isInjectedClassName() && 4950 "Broken injected-class-name"); 4951 } 4952 } 4953} 4954 4955void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4956 SourceLocation RBraceLoc) { 4957 AdjustDeclIfTemplate(TagD); 4958 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4959 Tag->setRBraceLoc(RBraceLoc); 4960 4961 if (isa<CXXRecordDecl>(Tag)) 4962 FieldCollector->FinishClass(); 4963 4964 // Exit this scope of this tag's definition. 4965 PopDeclContext(); 4966 4967 // Notify the consumer that we've defined a tag. 4968 Consumer.HandleTagDeclDefinition(Tag); 4969} 4970 4971// Note that FieldName may be null for anonymous bitfields. 4972bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4973 QualType FieldTy, const Expr *BitWidth, 4974 bool *ZeroWidth) { 4975 // Default to true; that shouldn't confuse checks for emptiness 4976 if (ZeroWidth) 4977 *ZeroWidth = true; 4978 4979 // C99 6.7.2.1p4 - verify the field type. 4980 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4981 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4982 // Handle incomplete types with specific error. 4983 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4984 return true; 4985 if (FieldName) 4986 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4987 << FieldName << FieldTy << BitWidth->getSourceRange(); 4988 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4989 << FieldTy << BitWidth->getSourceRange(); 4990 } 4991 4992 // If the bit-width is type- or value-dependent, don't try to check 4993 // it now. 4994 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4995 return false; 4996 4997 llvm::APSInt Value; 4998 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4999 return true; 5000 5001 if (Value != 0 && ZeroWidth) 5002 *ZeroWidth = false; 5003 5004 // Zero-width bitfield is ok for anonymous field. 5005 if (Value == 0 && FieldName) 5006 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5007 5008 if (Value.isSigned() && Value.isNegative()) { 5009 if (FieldName) 5010 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5011 << FieldName << Value.toString(10); 5012 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5013 << Value.toString(10); 5014 } 5015 5016 if (!FieldTy->isDependentType()) { 5017 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5018 if (Value.getZExtValue() > TypeSize) { 5019 if (FieldName) 5020 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5021 << FieldName << (unsigned)TypeSize; 5022 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5023 << (unsigned)TypeSize; 5024 } 5025 } 5026 5027 return false; 5028} 5029 5030/// ActOnField - Each field of a struct/union/class is passed into this in order 5031/// to create a FieldDecl object for it. 5032Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5033 SourceLocation DeclStart, 5034 Declarator &D, ExprTy *BitfieldWidth) { 5035 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5036 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5037 AS_public); 5038 return DeclPtrTy::make(Res); 5039} 5040 5041/// HandleField - Analyze a field of a C struct or a C++ data member. 5042/// 5043FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5044 SourceLocation DeclStart, 5045 Declarator &D, Expr *BitWidth, 5046 AccessSpecifier AS) { 5047 IdentifierInfo *II = D.getIdentifier(); 5048 SourceLocation Loc = DeclStart; 5049 if (II) Loc = D.getIdentifierLoc(); 5050 5051 TypeSourceInfo *TInfo = 0; 5052 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5053 if (getLangOptions().CPlusPlus) 5054 CheckExtraCXXDefaultArguments(D); 5055 5056 DiagnoseFunctionSpecifiers(D); 5057 5058 if (D.getDeclSpec().isThreadSpecified()) 5059 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5060 5061 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5062 ForRedeclaration); 5063 5064 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5065 // Maybe we will complain about the shadowed template parameter. 5066 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5067 // Just pretend that we didn't see the previous declaration. 5068 PrevDecl = 0; 5069 } 5070 5071 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5072 PrevDecl = 0; 5073 5074 bool Mutable 5075 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5076 SourceLocation TSSL = D.getSourceRange().getBegin(); 5077 FieldDecl *NewFD 5078 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5079 AS, PrevDecl, &D); 5080 if (NewFD->isInvalidDecl() && PrevDecl) { 5081 // Don't introduce NewFD into scope; there's already something 5082 // with the same name in the same scope. 5083 } else if (II) { 5084 PushOnScopeChains(NewFD, S); 5085 } else 5086 Record->addDecl(NewFD); 5087 5088 return NewFD; 5089} 5090 5091/// \brief Build a new FieldDecl and check its well-formedness. 5092/// 5093/// This routine builds a new FieldDecl given the fields name, type, 5094/// record, etc. \p PrevDecl should refer to any previous declaration 5095/// with the same name and in the same scope as the field to be 5096/// created. 5097/// 5098/// \returns a new FieldDecl. 5099/// 5100/// \todo The Declarator argument is a hack. It will be removed once 5101FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5102 TypeSourceInfo *TInfo, 5103 RecordDecl *Record, SourceLocation Loc, 5104 bool Mutable, Expr *BitWidth, 5105 SourceLocation TSSL, 5106 AccessSpecifier AS, NamedDecl *PrevDecl, 5107 Declarator *D) { 5108 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5109 bool InvalidDecl = false; 5110 if (D) InvalidDecl = D->isInvalidType(); 5111 5112 // If we receive a broken type, recover by assuming 'int' and 5113 // marking this declaration as invalid. 5114 if (T.isNull()) { 5115 InvalidDecl = true; 5116 T = Context.IntTy; 5117 } 5118 5119 QualType EltTy = Context.getBaseElementType(T); 5120 if (!EltTy->isDependentType() && 5121 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5122 InvalidDecl = true; 5123 5124 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5125 // than a variably modified type. 5126 if (!InvalidDecl && T->isVariablyModifiedType()) { 5127 bool SizeIsNegative; 5128 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5129 SizeIsNegative); 5130 if (!FixedTy.isNull()) { 5131 Diag(Loc, diag::warn_illegal_constant_array_size); 5132 T = FixedTy; 5133 } else { 5134 if (SizeIsNegative) 5135 Diag(Loc, diag::err_typecheck_negative_array_size); 5136 else 5137 Diag(Loc, diag::err_typecheck_field_variable_size); 5138 InvalidDecl = true; 5139 } 5140 } 5141 5142 // Fields can not have abstract class types 5143 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5144 diag::err_abstract_type_in_decl, 5145 AbstractFieldType)) 5146 InvalidDecl = true; 5147 5148 bool ZeroWidth = false; 5149 // If this is declared as a bit-field, check the bit-field. 5150 if (!InvalidDecl && BitWidth && 5151 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5152 InvalidDecl = true; 5153 DeleteExpr(BitWidth); 5154 BitWidth = 0; 5155 ZeroWidth = false; 5156 } 5157 5158 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5159 BitWidth, Mutable); 5160 if (InvalidDecl) 5161 NewFD->setInvalidDecl(); 5162 5163 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5164 Diag(Loc, diag::err_duplicate_member) << II; 5165 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5166 NewFD->setInvalidDecl(); 5167 } 5168 5169 if (getLangOptions().CPlusPlus) { 5170 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5171 5172 if (!T->isPODType()) 5173 CXXRecord->setPOD(false); 5174 if (!ZeroWidth) 5175 CXXRecord->setEmpty(false); 5176 5177 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5178 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5179 5180 if (!RDecl->hasTrivialConstructor()) 5181 CXXRecord->setHasTrivialConstructor(false); 5182 if (!RDecl->hasTrivialCopyConstructor()) 5183 CXXRecord->setHasTrivialCopyConstructor(false); 5184 if (!RDecl->hasTrivialCopyAssignment()) 5185 CXXRecord->setHasTrivialCopyAssignment(false); 5186 if (!RDecl->hasTrivialDestructor()) 5187 CXXRecord->setHasTrivialDestructor(false); 5188 5189 // C++ 9.5p1: An object of a class with a non-trivial 5190 // constructor, a non-trivial copy constructor, a non-trivial 5191 // destructor, or a non-trivial copy assignment operator 5192 // cannot be a member of a union, nor can an array of such 5193 // objects. 5194 // TODO: C++0x alters this restriction significantly. 5195 if (Record->isUnion()) { 5196 // We check for copy constructors before constructors 5197 // because otherwise we'll never get complaints about 5198 // copy constructors. 5199 5200 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5201 5202 CXXSpecialMember member; 5203 if (!RDecl->hasTrivialCopyConstructor()) 5204 member = CXXCopyConstructor; 5205 else if (!RDecl->hasTrivialConstructor()) 5206 member = CXXDefaultConstructor; 5207 else if (!RDecl->hasTrivialCopyAssignment()) 5208 member = CXXCopyAssignment; 5209 else if (!RDecl->hasTrivialDestructor()) 5210 member = CXXDestructor; 5211 else 5212 member = invalid; 5213 5214 if (member != invalid) { 5215 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5216 DiagnoseNontrivial(RT, member); 5217 NewFD->setInvalidDecl(); 5218 } 5219 } 5220 } 5221 } 5222 5223 // FIXME: We need to pass in the attributes given an AST 5224 // representation, not a parser representation. 5225 if (D) 5226 // FIXME: What to pass instead of TUScope? 5227 ProcessDeclAttributes(TUScope, NewFD, *D); 5228 5229 if (T.isObjCGCWeak()) 5230 Diag(Loc, diag::warn_attribute_weak_on_field); 5231 5232 NewFD->setAccess(AS); 5233 5234 // C++ [dcl.init.aggr]p1: 5235 // An aggregate is an array or a class (clause 9) with [...] no 5236 // private or protected non-static data members (clause 11). 5237 // A POD must be an aggregate. 5238 if (getLangOptions().CPlusPlus && 5239 (AS == AS_private || AS == AS_protected)) { 5240 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5241 CXXRecord->setAggregate(false); 5242 CXXRecord->setPOD(false); 5243 } 5244 5245 return NewFD; 5246} 5247 5248/// DiagnoseNontrivial - Given that a class has a non-trivial 5249/// special member, figure out why. 5250void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5251 QualType QT(T, 0U); 5252 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5253 5254 // Check whether the member was user-declared. 5255 switch (member) { 5256 case CXXDefaultConstructor: 5257 if (RD->hasUserDeclaredConstructor()) { 5258 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5259 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5260 const FunctionDecl *body = 0; 5261 ci->getBody(body); 5262 if (!body || 5263 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5264 SourceLocation CtorLoc = ci->getLocation(); 5265 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5266 return; 5267 } 5268 } 5269 5270 assert(0 && "found no user-declared constructors"); 5271 return; 5272 } 5273 break; 5274 5275 case CXXCopyConstructor: 5276 if (RD->hasUserDeclaredCopyConstructor()) { 5277 SourceLocation CtorLoc = 5278 RD->getCopyConstructor(Context, 0)->getLocation(); 5279 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5280 return; 5281 } 5282 break; 5283 5284 case CXXCopyAssignment: 5285 if (RD->hasUserDeclaredCopyAssignment()) { 5286 // FIXME: this should use the location of the copy 5287 // assignment, not the type. 5288 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5289 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5290 return; 5291 } 5292 break; 5293 5294 case CXXDestructor: 5295 if (RD->hasUserDeclaredDestructor()) { 5296 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5297 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5298 return; 5299 } 5300 break; 5301 } 5302 5303 typedef CXXRecordDecl::base_class_iterator base_iter; 5304 5305 // Virtual bases and members inhibit trivial copying/construction, 5306 // but not trivial destruction. 5307 if (member != CXXDestructor) { 5308 // Check for virtual bases. vbases includes indirect virtual bases, 5309 // so we just iterate through the direct bases. 5310 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5311 if (bi->isVirtual()) { 5312 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5313 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5314 return; 5315 } 5316 5317 // Check for virtual methods. 5318 typedef CXXRecordDecl::method_iterator meth_iter; 5319 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5320 ++mi) { 5321 if (mi->isVirtual()) { 5322 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5323 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5324 return; 5325 } 5326 } 5327 } 5328 5329 bool (CXXRecordDecl::*hasTrivial)() const; 5330 switch (member) { 5331 case CXXDefaultConstructor: 5332 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5333 case CXXCopyConstructor: 5334 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5335 case CXXCopyAssignment: 5336 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5337 case CXXDestructor: 5338 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5339 default: 5340 assert(0 && "unexpected special member"); return; 5341 } 5342 5343 // Check for nontrivial bases (and recurse). 5344 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5345 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5346 assert(BaseRT && "Don't know how to handle dependent bases"); 5347 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5348 if (!(BaseRecTy->*hasTrivial)()) { 5349 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5350 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5351 DiagnoseNontrivial(BaseRT, member); 5352 return; 5353 } 5354 } 5355 5356 // Check for nontrivial members (and recurse). 5357 typedef RecordDecl::field_iterator field_iter; 5358 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5359 ++fi) { 5360 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5361 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5362 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5363 5364 if (!(EltRD->*hasTrivial)()) { 5365 SourceLocation FLoc = (*fi)->getLocation(); 5366 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5367 DiagnoseNontrivial(EltRT, member); 5368 return; 5369 } 5370 } 5371 } 5372 5373 assert(0 && "found no explanation for non-trivial member"); 5374} 5375 5376/// TranslateIvarVisibility - Translate visibility from a token ID to an 5377/// AST enum value. 5378static ObjCIvarDecl::AccessControl 5379TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5380 switch (ivarVisibility) { 5381 default: assert(0 && "Unknown visitibility kind"); 5382 case tok::objc_private: return ObjCIvarDecl::Private; 5383 case tok::objc_public: return ObjCIvarDecl::Public; 5384 case tok::objc_protected: return ObjCIvarDecl::Protected; 5385 case tok::objc_package: return ObjCIvarDecl::Package; 5386 } 5387} 5388 5389/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5390/// in order to create an IvarDecl object for it. 5391Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5392 SourceLocation DeclStart, 5393 DeclPtrTy IntfDecl, 5394 Declarator &D, ExprTy *BitfieldWidth, 5395 tok::ObjCKeywordKind Visibility) { 5396 5397 IdentifierInfo *II = D.getIdentifier(); 5398 Expr *BitWidth = (Expr*)BitfieldWidth; 5399 SourceLocation Loc = DeclStart; 5400 if (II) Loc = D.getIdentifierLoc(); 5401 5402 // FIXME: Unnamed fields can be handled in various different ways, for 5403 // example, unnamed unions inject all members into the struct namespace! 5404 5405 TypeSourceInfo *TInfo = 0; 5406 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5407 5408 if (BitWidth) { 5409 // 6.7.2.1p3, 6.7.2.1p4 5410 if (VerifyBitField(Loc, II, T, BitWidth)) { 5411 D.setInvalidType(); 5412 DeleteExpr(BitWidth); 5413 BitWidth = 0; 5414 } 5415 } else { 5416 // Not a bitfield. 5417 5418 // validate II. 5419 5420 } 5421 5422 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5423 // than a variably modified type. 5424 if (T->isVariablyModifiedType()) { 5425 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5426 D.setInvalidType(); 5427 } 5428 5429 // Get the visibility (access control) for this ivar. 5430 ObjCIvarDecl::AccessControl ac = 5431 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5432 : ObjCIvarDecl::None; 5433 // Must set ivar's DeclContext to its enclosing interface. 5434 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5435 DeclContext *EnclosingContext; 5436 if (ObjCImplementationDecl *IMPDecl = 5437 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5438 // Case of ivar declared in an implementation. Context is that of its class. 5439 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5440 assert(IDecl && "No class- ActOnIvar"); 5441 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5442 } else 5443 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5444 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5445 5446 // Construct the decl. 5447 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5448 EnclosingContext, Loc, II, T, 5449 TInfo, ac, (Expr *)BitfieldWidth); 5450 5451 if (II) { 5452 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5453 ForRedeclaration); 5454 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5455 && !isa<TagDecl>(PrevDecl)) { 5456 Diag(Loc, diag::err_duplicate_member) << II; 5457 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5458 NewID->setInvalidDecl(); 5459 } 5460 } 5461 5462 // Process attributes attached to the ivar. 5463 ProcessDeclAttributes(S, NewID, D); 5464 5465 if (D.isInvalidType()) 5466 NewID->setInvalidDecl(); 5467 5468 if (II) { 5469 // FIXME: When interfaces are DeclContexts, we'll need to add 5470 // these to the interface. 5471 S->AddDecl(DeclPtrTy::make(NewID)); 5472 IdResolver.AddDecl(NewID); 5473 } 5474 5475 return DeclPtrTy::make(NewID); 5476} 5477 5478void Sema::ActOnFields(Scope* S, 5479 SourceLocation RecLoc, DeclPtrTy RecDecl, 5480 DeclPtrTy *Fields, unsigned NumFields, 5481 SourceLocation LBrac, SourceLocation RBrac, 5482 AttributeList *Attr) { 5483 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5484 assert(EnclosingDecl && "missing record or interface decl"); 5485 5486 // If the decl this is being inserted into is invalid, then it may be a 5487 // redeclaration or some other bogus case. Don't try to add fields to it. 5488 if (EnclosingDecl->isInvalidDecl()) { 5489 // FIXME: Deallocate fields? 5490 return; 5491 } 5492 5493 5494 // Verify that all the fields are okay. 5495 unsigned NumNamedMembers = 0; 5496 llvm::SmallVector<FieldDecl*, 32> RecFields; 5497 5498 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5499 for (unsigned i = 0; i != NumFields; ++i) { 5500 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5501 5502 // Get the type for the field. 5503 Type *FDTy = FD->getType().getTypePtr(); 5504 5505 if (!FD->isAnonymousStructOrUnion()) { 5506 // Remember all fields written by the user. 5507 RecFields.push_back(FD); 5508 } 5509 5510 // If the field is already invalid for some reason, don't emit more 5511 // diagnostics about it. 5512 if (FD->isInvalidDecl()) { 5513 EnclosingDecl->setInvalidDecl(); 5514 continue; 5515 } 5516 5517 // C99 6.7.2.1p2: 5518 // A structure or union shall not contain a member with 5519 // incomplete or function type (hence, a structure shall not 5520 // contain an instance of itself, but may contain a pointer to 5521 // an instance of itself), except that the last member of a 5522 // structure with more than one named member may have incomplete 5523 // array type; such a structure (and any union containing, 5524 // possibly recursively, a member that is such a structure) 5525 // shall not be a member of a structure or an element of an 5526 // array. 5527 if (FDTy->isFunctionType()) { 5528 // Field declared as a function. 5529 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5530 << FD->getDeclName(); 5531 FD->setInvalidDecl(); 5532 EnclosingDecl->setInvalidDecl(); 5533 continue; 5534 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5535 Record && Record->isStruct()) { 5536 // Flexible array member. 5537 if (NumNamedMembers < 1) { 5538 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5539 << FD->getDeclName(); 5540 FD->setInvalidDecl(); 5541 EnclosingDecl->setInvalidDecl(); 5542 continue; 5543 } 5544 // Okay, we have a legal flexible array member at the end of the struct. 5545 if (Record) 5546 Record->setHasFlexibleArrayMember(true); 5547 } else if (!FDTy->isDependentType() && 5548 RequireCompleteType(FD->getLocation(), FD->getType(), 5549 diag::err_field_incomplete)) { 5550 // Incomplete type 5551 FD->setInvalidDecl(); 5552 EnclosingDecl->setInvalidDecl(); 5553 continue; 5554 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5555 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5556 // If this is a member of a union, then entire union becomes "flexible". 5557 if (Record && Record->isUnion()) { 5558 Record->setHasFlexibleArrayMember(true); 5559 } else { 5560 // If this is a struct/class and this is not the last element, reject 5561 // it. Note that GCC supports variable sized arrays in the middle of 5562 // structures. 5563 if (i != NumFields-1) 5564 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5565 << FD->getDeclName() << FD->getType(); 5566 else { 5567 // We support flexible arrays at the end of structs in 5568 // other structs as an extension. 5569 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5570 << FD->getDeclName(); 5571 if (Record) 5572 Record->setHasFlexibleArrayMember(true); 5573 } 5574 } 5575 } 5576 if (Record && FDTTy->getDecl()->hasObjectMember()) 5577 Record->setHasObjectMember(true); 5578 } else if (FDTy->isObjCInterfaceType()) { 5579 /// A field cannot be an Objective-c object 5580 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5581 FD->setInvalidDecl(); 5582 EnclosingDecl->setInvalidDecl(); 5583 continue; 5584 } else if (getLangOptions().ObjC1 && 5585 getLangOptions().getGCMode() != LangOptions::NonGC && 5586 Record && 5587 (FD->getType()->isObjCObjectPointerType() || 5588 FD->getType().isObjCGCStrong())) 5589 Record->setHasObjectMember(true); 5590 // Keep track of the number of named members. 5591 if (FD->getIdentifier()) 5592 ++NumNamedMembers; 5593 } 5594 5595 // Okay, we successfully defined 'Record'. 5596 if (Record) { 5597 Record->completeDefinition(Context); 5598 } else { 5599 ObjCIvarDecl **ClsFields = 5600 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5601 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5602 ID->setIVarList(ClsFields, RecFields.size(), Context); 5603 ID->setLocEnd(RBrac); 5604 // Add ivar's to class's DeclContext. 5605 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5606 ClsFields[i]->setLexicalDeclContext(ID); 5607 ID->addDecl(ClsFields[i]); 5608 } 5609 // Must enforce the rule that ivars in the base classes may not be 5610 // duplicates. 5611 if (ID->getSuperClass()) { 5612 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5613 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5614 ObjCIvarDecl* Ivar = (*IVI); 5615 5616 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5617 ObjCIvarDecl* prevIvar = 5618 ID->getSuperClass()->lookupInstanceVariable(II); 5619 if (prevIvar) { 5620 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5621 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5622 } 5623 } 5624 } 5625 } 5626 } else if (ObjCImplementationDecl *IMPDecl = 5627 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5628 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5629 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5630 // Ivar declared in @implementation never belongs to the implementation. 5631 // Only it is in implementation's lexical context. 5632 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5633 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5634 } 5635 } 5636 5637 if (Attr) 5638 ProcessDeclAttributeList(S, Record, Attr); 5639} 5640 5641EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5642 EnumConstantDecl *LastEnumConst, 5643 SourceLocation IdLoc, 5644 IdentifierInfo *Id, 5645 ExprArg val) { 5646 Expr *Val = (Expr *)val.get(); 5647 5648 llvm::APSInt EnumVal(32); 5649 QualType EltTy; 5650 if (Val) { 5651 if (Val->isTypeDependent()) 5652 EltTy = Context.DependentTy; 5653 else { 5654 // Make sure to promote the operand type to int. 5655 UsualUnaryConversions(Val); 5656 if (Val != val.get()) { 5657 val.release(); 5658 val = Val; 5659 } 5660 5661 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5662 SourceLocation ExpLoc; 5663 if (!Val->isValueDependent() && 5664 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5665 Val = 0; 5666 } else { 5667 EltTy = Val->getType(); 5668 } 5669 } 5670 } 5671 5672 if (!Val) { 5673 if (LastEnumConst) { 5674 // Assign the last value + 1. 5675 EnumVal = LastEnumConst->getInitVal(); 5676 ++EnumVal; 5677 5678 // Check for overflow on increment. 5679 if (EnumVal < LastEnumConst->getInitVal()) 5680 Diag(IdLoc, diag::warn_enum_value_overflow); 5681 5682 EltTy = LastEnumConst->getType(); 5683 } else { 5684 // First value, set to zero. 5685 EltTy = Context.IntTy; 5686 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5687 } 5688 } 5689 5690 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5691 5692 val.release(); 5693 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5694 Val, EnumVal); 5695} 5696 5697 5698Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5699 DeclPtrTy lastEnumConst, 5700 SourceLocation IdLoc, 5701 IdentifierInfo *Id, 5702 SourceLocation EqualLoc, ExprTy *val) { 5703 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5704 EnumConstantDecl *LastEnumConst = 5705 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5706 Expr *Val = static_cast<Expr*>(val); 5707 5708 // The scope passed in may not be a decl scope. Zip up the scope tree until 5709 // we find one that is. 5710 S = getNonFieldDeclScope(S); 5711 5712 // Verify that there isn't already something declared with this name in this 5713 // scope. 5714 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5715 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5716 // Maybe we will complain about the shadowed template parameter. 5717 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5718 // Just pretend that we didn't see the previous declaration. 5719 PrevDecl = 0; 5720 } 5721 5722 if (PrevDecl) { 5723 // When in C++, we may get a TagDecl with the same name; in this case the 5724 // enum constant will 'hide' the tag. 5725 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5726 "Received TagDecl when not in C++!"); 5727 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5728 if (isa<EnumConstantDecl>(PrevDecl)) 5729 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5730 else 5731 Diag(IdLoc, diag::err_redefinition) << Id; 5732 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5733 if (Val) Val->Destroy(Context); 5734 return DeclPtrTy(); 5735 } 5736 } 5737 5738 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5739 IdLoc, Id, Owned(Val)); 5740 5741 // Register this decl in the current scope stack. 5742 if (New) 5743 PushOnScopeChains(New, S); 5744 5745 return DeclPtrTy::make(New); 5746} 5747 5748void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5749 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5750 DeclPtrTy *Elements, unsigned NumElements, 5751 Scope *S, AttributeList *Attr) { 5752 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5753 QualType EnumType = Context.getTypeDeclType(Enum); 5754 5755 if (Attr) 5756 ProcessDeclAttributeList(S, Enum, Attr); 5757 5758 // TODO: If the result value doesn't fit in an int, it must be a long or long 5759 // long value. ISO C does not support this, but GCC does as an extension, 5760 // emit a warning. 5761 unsigned IntWidth = Context.Target.getIntWidth(); 5762 unsigned CharWidth = Context.Target.getCharWidth(); 5763 unsigned ShortWidth = Context.Target.getShortWidth(); 5764 5765 // Verify that all the values are okay, compute the size of the values, and 5766 // reverse the list. 5767 unsigned NumNegativeBits = 0; 5768 unsigned NumPositiveBits = 0; 5769 5770 // Keep track of whether all elements have type int. 5771 bool AllElementsInt = true; 5772 5773 for (unsigned i = 0; i != NumElements; ++i) { 5774 EnumConstantDecl *ECD = 5775 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5776 if (!ECD) continue; // Already issued a diagnostic. 5777 5778 // If the enum value doesn't fit in an int, emit an extension warning. 5779 const llvm::APSInt &InitVal = ECD->getInitVal(); 5780 assert(InitVal.getBitWidth() >= IntWidth && 5781 "Should have promoted value to int"); 5782 if (InitVal.getBitWidth() > IntWidth) { 5783 llvm::APSInt V(InitVal); 5784 V.trunc(IntWidth); 5785 V.extend(InitVal.getBitWidth()); 5786 if (V != InitVal) 5787 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5788 << InitVal.toString(10); 5789 } 5790 5791 // Keep track of the size of positive and negative values. 5792 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5793 NumPositiveBits = std::max(NumPositiveBits, 5794 (unsigned)InitVal.getActiveBits()); 5795 else 5796 NumNegativeBits = std::max(NumNegativeBits, 5797 (unsigned)InitVal.getMinSignedBits()); 5798 5799 // Keep track of whether every enum element has type int (very commmon). 5800 if (AllElementsInt) 5801 AllElementsInt = ECD->getType() == Context.IntTy; 5802 } 5803 5804 // Figure out the type that should be used for this enum. 5805 // FIXME: Support -fshort-enums. 5806 QualType BestType; 5807 unsigned BestWidth; 5808 5809 // C++0x N3000 [conv.prom]p3: 5810 // An rvalue of an unscoped enumeration type whose underlying 5811 // type is not fixed can be converted to an rvalue of the first 5812 // of the following types that can represent all the values of 5813 // the enumeration: int, unsigned int, long int, unsigned long 5814 // int, long long int, or unsigned long long int. 5815 // C99 6.4.4.3p2: 5816 // An identifier declared as an enumeration constant has type int. 5817 // The C99 rule is modified by a gcc extension 5818 QualType BestPromotionType; 5819 5820 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5821 5822 if (NumNegativeBits) { 5823 // If there is a negative value, figure out the smallest integer type (of 5824 // int/long/longlong) that fits. 5825 // If it's packed, check also if it fits a char or a short. 5826 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5827 BestType = Context.SignedCharTy; 5828 BestWidth = CharWidth; 5829 } else if (Packed && NumNegativeBits <= ShortWidth && 5830 NumPositiveBits < ShortWidth) { 5831 BestType = Context.ShortTy; 5832 BestWidth = ShortWidth; 5833 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5834 BestType = Context.IntTy; 5835 BestWidth = IntWidth; 5836 } else { 5837 BestWidth = Context.Target.getLongWidth(); 5838 5839 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5840 BestType = Context.LongTy; 5841 } else { 5842 BestWidth = Context.Target.getLongLongWidth(); 5843 5844 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5845 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5846 BestType = Context.LongLongTy; 5847 } 5848 } 5849 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5850 } else { 5851 // If there is no negative value, figure out which of uint, ulong, ulonglong 5852 // fits. 5853 // If it's packed, check also if it fits a char or a short. 5854 if (Packed && NumPositiveBits <= CharWidth) { 5855 BestType = Context.UnsignedCharTy; 5856 BestPromotionType = Context.IntTy; 5857 BestWidth = CharWidth; 5858 } else if (Packed && NumPositiveBits <= ShortWidth) { 5859 BestType = Context.UnsignedShortTy; 5860 BestPromotionType = Context.IntTy; 5861 BestWidth = ShortWidth; 5862 } else if (NumPositiveBits <= IntWidth) { 5863 BestType = Context.UnsignedIntTy; 5864 BestWidth = IntWidth; 5865 BestPromotionType = (NumPositiveBits == BestWidth 5866 ? Context.UnsignedIntTy : Context.IntTy); 5867 } else if (NumPositiveBits <= 5868 (BestWidth = Context.Target.getLongWidth())) { 5869 BestType = Context.UnsignedLongTy; 5870 BestPromotionType = (NumPositiveBits == BestWidth 5871 ? Context.UnsignedLongTy : Context.LongTy); 5872 } else { 5873 BestWidth = Context.Target.getLongLongWidth(); 5874 assert(NumPositiveBits <= BestWidth && 5875 "How could an initializer get larger than ULL?"); 5876 BestType = Context.UnsignedLongLongTy; 5877 BestPromotionType = (NumPositiveBits == BestWidth 5878 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5879 } 5880 } 5881 5882 // If we're in C and the promotion type is larger than an int, just 5883 // use the underlying type, which is generally the unsigned integer 5884 // type of the same rank as the promotion type. This is how the gcc 5885 // extension works. 5886 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5887 BestPromotionType = BestType; 5888 5889 // Loop over all of the enumerator constants, changing their types to match 5890 // the type of the enum if needed. 5891 for (unsigned i = 0; i != NumElements; ++i) { 5892 EnumConstantDecl *ECD = 5893 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5894 if (!ECD) continue; // Already issued a diagnostic. 5895 5896 // Standard C says the enumerators have int type, but we allow, as an 5897 // extension, the enumerators to be larger than int size. If each 5898 // enumerator value fits in an int, type it as an int, otherwise type it the 5899 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5900 // that X has type 'int', not 'unsigned'. 5901 if (ECD->getType() == Context.IntTy) { 5902 // Make sure the init value is signed. 5903 llvm::APSInt IV = ECD->getInitVal(); 5904 IV.setIsSigned(true); 5905 ECD->setInitVal(IV); 5906 5907 if (getLangOptions().CPlusPlus) 5908 // C++ [dcl.enum]p4: Following the closing brace of an 5909 // enum-specifier, each enumerator has the type of its 5910 // enumeration. 5911 ECD->setType(EnumType); 5912 continue; // Already int type. 5913 } 5914 5915 // Determine whether the value fits into an int. 5916 llvm::APSInt InitVal = ECD->getInitVal(); 5917 bool FitsInInt; 5918 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5919 FitsInInt = InitVal.getActiveBits() < IntWidth; 5920 else 5921 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5922 5923 // If it fits into an integer type, force it. Otherwise force it to match 5924 // the enum decl type. 5925 QualType NewTy; 5926 unsigned NewWidth; 5927 bool NewSign; 5928 if (FitsInInt) { 5929 NewTy = Context.IntTy; 5930 NewWidth = IntWidth; 5931 NewSign = true; 5932 } else if (ECD->getType() == BestType) { 5933 // Already the right type! 5934 if (getLangOptions().CPlusPlus) 5935 // C++ [dcl.enum]p4: Following the closing brace of an 5936 // enum-specifier, each enumerator has the type of its 5937 // enumeration. 5938 ECD->setType(EnumType); 5939 continue; 5940 } else { 5941 NewTy = BestType; 5942 NewWidth = BestWidth; 5943 NewSign = BestType->isSignedIntegerType(); 5944 } 5945 5946 // Adjust the APSInt value. 5947 InitVal.extOrTrunc(NewWidth); 5948 InitVal.setIsSigned(NewSign); 5949 ECD->setInitVal(InitVal); 5950 5951 // Adjust the Expr initializer and type. 5952 if (ECD->getInitExpr()) 5953 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5954 CastExpr::CK_IntegralCast, 5955 ECD->getInitExpr(), 5956 /*isLvalue=*/false)); 5957 if (getLangOptions().CPlusPlus) 5958 // C++ [dcl.enum]p4: Following the closing brace of an 5959 // enum-specifier, each enumerator has the type of its 5960 // enumeration. 5961 ECD->setType(EnumType); 5962 else 5963 ECD->setType(NewTy); 5964 } 5965 5966 Enum->completeDefinition(Context, BestType, BestPromotionType); 5967} 5968 5969Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5970 ExprArg expr) { 5971 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5972 5973 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5974 Loc, AsmString); 5975 CurContext->addDecl(New); 5976 return DeclPtrTy::make(New); 5977} 5978 5979void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5980 SourceLocation PragmaLoc, 5981 SourceLocation NameLoc) { 5982 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5983 5984 if (PrevDecl) { 5985 PrevDecl->addAttr(::new (Context) WeakAttr()); 5986 } else { 5987 (void)WeakUndeclaredIdentifiers.insert( 5988 std::pair<IdentifierInfo*,WeakInfo> 5989 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5990 } 5991} 5992 5993void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5994 IdentifierInfo* AliasName, 5995 SourceLocation PragmaLoc, 5996 SourceLocation NameLoc, 5997 SourceLocation AliasNameLoc) { 5998 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5999 WeakInfo W = WeakInfo(Name, NameLoc); 6000 6001 if (PrevDecl) { 6002 if (!PrevDecl->hasAttr<AliasAttr>()) 6003 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6004 DeclApplyPragmaWeak(TUScope, ND, W); 6005 } else { 6006 (void)WeakUndeclaredIdentifiers.insert( 6007 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6008 } 6009} 6010