SemaDecl.cpp revision d87b61f6398bab21176f73818a8d11ca1c3632c8
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 || isa<InitListExpr>(Init)) { 3504 InitializedEntity Entity 3505 = InitializedEntity::InitializeVariable(VDecl); 3506 3507 // FIXME: Poor source location information. 3508 InitializationKind Kind 3509 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3510 SourceLocation(), 3511 SourceLocation()) 3512 : InitializationKind::CreateCopy(VDecl->getLocation(), 3513 SourceLocation()); 3514 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3515 if (InitSeq) { 3516 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3517 MultiExprArg(*this, (void**)&Init, 1), 3518 &DclT); 3519 if (Result.isInvalid()) { 3520 VDecl->setInvalidDecl(); 3521 return; 3522 } 3523 3524 Init = Result.takeAs<Expr>(); 3525 } else { 3526 InitSeq.Diagnose(*this, Entity, Kind, &Init, 1); 3527 VDecl->setInvalidDecl(); 3528 return; 3529 } 3530 } else if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3531 VDecl->getDeclName(), DirectInit)) 3532 VDecl->setInvalidDecl(); 3533 3534 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3535 // Don't check invalid declarations to avoid emitting useless diagnostics. 3536 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3537 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3538 CheckForConstantInitializer(Init, DclT); 3539 } 3540 } 3541 } else if (VDecl->isStaticDataMember() && 3542 VDecl->getLexicalDeclContext()->isRecord()) { 3543 // This is an in-class initialization for a static data member, e.g., 3544 // 3545 // struct S { 3546 // static const int value = 17; 3547 // }; 3548 3549 // Attach the initializer 3550 VDecl->setInit(Context, Init); 3551 3552 // C++ [class.mem]p4: 3553 // A member-declarator can contain a constant-initializer only 3554 // if it declares a static member (9.4) of const integral or 3555 // const enumeration type, see 9.4.2. 3556 QualType T = VDecl->getType(); 3557 if (!T->isDependentType() && 3558 (!Context.getCanonicalType(T).isConstQualified() || 3559 !T->isIntegralType())) { 3560 Diag(VDecl->getLocation(), diag::err_member_initialization) 3561 << VDecl->getDeclName() << Init->getSourceRange(); 3562 VDecl->setInvalidDecl(); 3563 } else { 3564 // C++ [class.static.data]p4: 3565 // If a static data member is of const integral or const 3566 // enumeration type, its declaration in the class definition 3567 // can specify a constant-initializer which shall be an 3568 // integral constant expression (5.19). 3569 if (!Init->isTypeDependent() && 3570 !Init->getType()->isIntegralType()) { 3571 // We have a non-dependent, non-integral or enumeration type. 3572 Diag(Init->getSourceRange().getBegin(), 3573 diag::err_in_class_initializer_non_integral_type) 3574 << Init->getType() << Init->getSourceRange(); 3575 VDecl->setInvalidDecl(); 3576 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3577 // Check whether the expression is a constant expression. 3578 llvm::APSInt Value; 3579 SourceLocation Loc; 3580 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3581 Diag(Loc, diag::err_in_class_initializer_non_constant) 3582 << Init->getSourceRange(); 3583 VDecl->setInvalidDecl(); 3584 } else if (!VDecl->getType()->isDependentType()) 3585 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3586 } 3587 } 3588 } else if (VDecl->isFileVarDecl()) { 3589 if (VDecl->getStorageClass() == VarDecl::Extern) 3590 Diag(VDecl->getLocation(), diag::warn_extern_init); 3591 if (!VDecl->isInvalidDecl()) 3592 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3593 VDecl->getDeclName(), DirectInit)) 3594 VDecl->setInvalidDecl(); 3595 3596 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3597 // Don't check invalid declarations to avoid emitting useless diagnostics. 3598 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3599 // C99 6.7.8p4. All file scoped initializers need to be constant. 3600 CheckForConstantInitializer(Init, DclT); 3601 } 3602 } 3603 // If the type changed, it means we had an incomplete type that was 3604 // completed by the initializer. For example: 3605 // int ary[] = { 1, 3, 5 }; 3606 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3607 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3608 VDecl->setType(DclT); 3609 Init->setType(DclT); 3610 } 3611 3612 Init = MaybeCreateCXXExprWithTemporaries(Init, 3613 /*ShouldDestroyTemporaries=*/true); 3614 // Attach the initializer to the decl. 3615 VDecl->setInit(Context, Init); 3616 3617 // If the previous declaration of VDecl was a tentative definition, 3618 // remove it from the set of tentative definitions. 3619 if (VDecl->getPreviousDeclaration() && 3620 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3621 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3622 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3623 } 3624 3625 return; 3626} 3627 3628void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3629 bool TypeContainsUndeducedAuto) { 3630 Decl *RealDecl = dcl.getAs<Decl>(); 3631 3632 // If there is no declaration, there was an error parsing it. Just ignore it. 3633 if (RealDecl == 0) 3634 return; 3635 3636 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3637 QualType Type = Var->getType(); 3638 3639 // Record tentative definitions. 3640 if (Var->isTentativeDefinition(Context)) { 3641 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3642 InsertPair = 3643 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3644 3645 // Keep the latest definition in the map. If we see 'int i; int i;' we 3646 // want the second one in the map. 3647 InsertPair.first->second = Var; 3648 3649 // However, for the list, we don't care about the order, just make sure 3650 // that there are no dupes for a given declaration name. 3651 if (InsertPair.second) 3652 TentativeDefinitionList.push_back(Var->getDeclName()); 3653 } 3654 3655 // C++ [dcl.init.ref]p3: 3656 // The initializer can be omitted for a reference only in a 3657 // parameter declaration (8.3.5), in the declaration of a 3658 // function return type, in the declaration of a class member 3659 // within its class declaration (9.2), and where the extern 3660 // specifier is explicitly used. 3661 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3662 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3663 << Var->getDeclName() 3664 << SourceRange(Var->getLocation(), Var->getLocation()); 3665 Var->setInvalidDecl(); 3666 return; 3667 } 3668 3669 // C++0x [dcl.spec.auto]p3 3670 if (TypeContainsUndeducedAuto) { 3671 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3672 << Var->getDeclName() << Type; 3673 Var->setInvalidDecl(); 3674 return; 3675 } 3676 3677 // An array without size is an incomplete type, and there are no special 3678 // rules in C++ to make such a definition acceptable. 3679 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3680 !Var->hasExternalStorage()) { 3681 Diag(Var->getLocation(), 3682 diag::err_typecheck_incomplete_array_needs_initializer); 3683 Var->setInvalidDecl(); 3684 return; 3685 } 3686 3687 // C++ [temp.expl.spec]p15: 3688 // An explicit specialization of a static data member of a template is a 3689 // definition if the declaration includes an initializer; otherwise, it 3690 // is a declaration. 3691 if (Var->isStaticDataMember() && 3692 Var->getInstantiatedFromStaticDataMember() && 3693 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3694 return; 3695 3696 // C++ [dcl.init]p9: 3697 // If no initializer is specified for an object, and the object 3698 // is of (possibly cv-qualified) non-POD class type (or array 3699 // thereof), the object shall be default-initialized; if the 3700 // object is of const-qualified type, the underlying class type 3701 // shall have a user-declared default constructor. 3702 // 3703 // FIXME: Diagnose the "user-declared default constructor" bit. 3704 if (getLangOptions().CPlusPlus) { 3705 QualType InitType = Type; 3706 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3707 InitType = Context.getBaseElementType(Array); 3708 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3709 InitType->isRecordType() && !InitType->isDependentType()) { 3710 if (!RequireCompleteType(Var->getLocation(), InitType, 3711 diag::err_invalid_incomplete_type_use)) { 3712 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3713 3714 CXXConstructorDecl *Constructor 3715 = PerformInitializationByConstructor(InitType, 3716 MultiExprArg(*this, 0, 0), 3717 Var->getLocation(), 3718 SourceRange(Var->getLocation(), 3719 Var->getLocation()), 3720 Var->getDeclName(), 3721 InitializationKind::CreateDefault(Var->getLocation()), 3722 ConstructorArgs); 3723 3724 // FIXME: Location info for the variable initialization? 3725 if (!Constructor) 3726 Var->setInvalidDecl(); 3727 else { 3728 // FIXME: Cope with initialization of arrays 3729 if (!Constructor->isTrivial() && 3730 InitializeVarWithConstructor(Var, Constructor, 3731 move_arg(ConstructorArgs))) 3732 Var->setInvalidDecl(); 3733 3734 FinalizeVarWithDestructor(Var, InitType); 3735 } 3736 } else { 3737 Var->setInvalidDecl(); 3738 } 3739 } 3740 3741 // The variable can not have an abstract class type. 3742 if (RequireNonAbstractType(Var->getLocation(), Type, 3743 diag::err_abstract_type_in_decl, 3744 AbstractVariableType)) 3745 Var->setInvalidDecl(); 3746 } 3747 3748#if 0 3749 // FIXME: Temporarily disabled because we are not properly parsing 3750 // linkage specifications on declarations, e.g., 3751 // 3752 // extern "C" const CGPoint CGPointerZero; 3753 // 3754 // C++ [dcl.init]p9: 3755 // 3756 // If no initializer is specified for an object, and the 3757 // object is of (possibly cv-qualified) non-POD class type (or 3758 // array thereof), the object shall be default-initialized; if 3759 // the object is of const-qualified type, the underlying class 3760 // type shall have a user-declared default 3761 // constructor. Otherwise, if no initializer is specified for 3762 // an object, the object and its subobjects, if any, have an 3763 // indeterminate initial value; if the object or any of its 3764 // subobjects are of const-qualified type, the program is 3765 // ill-formed. 3766 // 3767 // This isn't technically an error in C, so we don't diagnose it. 3768 // 3769 // FIXME: Actually perform the POD/user-defined default 3770 // constructor check. 3771 if (getLangOptions().CPlusPlus && 3772 Context.getCanonicalType(Type).isConstQualified() && 3773 !Var->hasExternalStorage()) 3774 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3775 << Var->getName() 3776 << SourceRange(Var->getLocation(), Var->getLocation()); 3777#endif 3778 } 3779} 3780 3781Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3782 DeclPtrTy *Group, 3783 unsigned NumDecls) { 3784 llvm::SmallVector<Decl*, 8> Decls; 3785 3786 if (DS.isTypeSpecOwned()) 3787 Decls.push_back((Decl*)DS.getTypeRep()); 3788 3789 for (unsigned i = 0; i != NumDecls; ++i) 3790 if (Decl *D = Group[i].getAs<Decl>()) 3791 Decls.push_back(D); 3792 3793 // Perform semantic analysis that depends on having fully processed both 3794 // the declarator and initializer. 3795 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3796 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3797 if (!IDecl) 3798 continue; 3799 QualType T = IDecl->getType(); 3800 3801 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3802 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3803 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3804 if (T->isDependentType()) { 3805 // If T is dependent, we should not require a complete type. 3806 // (RequireCompleteType shouldn't be called with dependent types.) 3807 // But we still can at least check if we've got an array of unspecified 3808 // size without an initializer. 3809 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3810 !IDecl->getInit()) { 3811 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3812 << T; 3813 IDecl->setInvalidDecl(); 3814 } 3815 } else if (!IDecl->isInvalidDecl()) { 3816 // If T is an incomplete array type with an initializer list that is 3817 // dependent on something, its size has not been fixed. We could attempt 3818 // to fix the size for such arrays, but we would still have to check 3819 // here for initializers containing a C++0x vararg expansion, e.g. 3820 // template <typename... Args> void f(Args... args) { 3821 // int vals[] = { args }; 3822 // } 3823 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3824 Expr *Init = IDecl->getInit(); 3825 if (IAT && Init && 3826 (Init->isTypeDependent() || Init->isValueDependent())) { 3827 // Check that the member type of the array is complete, at least. 3828 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3829 diag::err_typecheck_decl_incomplete_type)) 3830 IDecl->setInvalidDecl(); 3831 } else if (RequireCompleteType(IDecl->getLocation(), T, 3832 diag::err_typecheck_decl_incomplete_type)) 3833 IDecl->setInvalidDecl(); 3834 } 3835 } 3836 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3837 // object that has file scope without an initializer, and without a 3838 // storage-class specifier or with the storage-class specifier "static", 3839 // constitutes a tentative definition. Note: A tentative definition with 3840 // external linkage is valid (C99 6.2.2p5). 3841 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3842 if (const IncompleteArrayType *ArrayT 3843 = Context.getAsIncompleteArrayType(T)) { 3844 if (RequireCompleteType(IDecl->getLocation(), 3845 ArrayT->getElementType(), 3846 diag::err_illegal_decl_array_incomplete_type)) 3847 IDecl->setInvalidDecl(); 3848 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3849 // C99 6.9.2p3: If the declaration of an identifier for an object is 3850 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3851 // declared type shall not be an incomplete type. 3852 // NOTE: code such as the following 3853 // static struct s; 3854 // struct s { int a; }; 3855 // is accepted by gcc. Hence here we issue a warning instead of 3856 // an error and we do not invalidate the static declaration. 3857 // NOTE: to avoid multiple warnings, only check the first declaration. 3858 if (IDecl->getPreviousDeclaration() == 0) 3859 RequireCompleteType(IDecl->getLocation(), T, 3860 diag::ext_typecheck_decl_incomplete_type); 3861 } 3862 } 3863 } 3864 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3865 Decls.data(), Decls.size())); 3866} 3867 3868 3869/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3870/// to introduce parameters into function prototype scope. 3871Sema::DeclPtrTy 3872Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3873 const DeclSpec &DS = D.getDeclSpec(); 3874 3875 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3876 VarDecl::StorageClass StorageClass = VarDecl::None; 3877 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3878 StorageClass = VarDecl::Register; 3879 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3880 Diag(DS.getStorageClassSpecLoc(), 3881 diag::err_invalid_storage_class_in_func_decl); 3882 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3883 } 3884 3885 if (D.getDeclSpec().isThreadSpecified()) 3886 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3887 3888 DiagnoseFunctionSpecifiers(D); 3889 3890 // Check that there are no default arguments inside the type of this 3891 // parameter (C++ only). 3892 if (getLangOptions().CPlusPlus) 3893 CheckExtraCXXDefaultArguments(D); 3894 3895 TypeSourceInfo *TInfo = 0; 3896 TagDecl *OwnedDecl = 0; 3897 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3898 3899 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3900 // C++ [dcl.fct]p6: 3901 // Types shall not be defined in return or parameter types. 3902 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3903 << Context.getTypeDeclType(OwnedDecl); 3904 } 3905 3906 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3907 // Can this happen for params? We already checked that they don't conflict 3908 // among each other. Here they can only shadow globals, which is ok. 3909 IdentifierInfo *II = D.getIdentifier(); 3910 if (II) { 3911 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3912 if (PrevDecl->isTemplateParameter()) { 3913 // Maybe we will complain about the shadowed template parameter. 3914 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3915 // Just pretend that we didn't see the previous declaration. 3916 PrevDecl = 0; 3917 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3918 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3919 3920 // Recover by removing the name 3921 II = 0; 3922 D.SetIdentifier(0, D.getIdentifierLoc()); 3923 } 3924 } 3925 } 3926 3927 // Parameters can not be abstract class types. 3928 // For record types, this is done by the AbstractClassUsageDiagnoser once 3929 // the class has been completely parsed. 3930 if (!CurContext->isRecord() && 3931 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3932 diag::err_abstract_type_in_decl, 3933 AbstractParamType)) 3934 D.setInvalidType(true); 3935 3936 QualType T = adjustParameterType(parmDeclType); 3937 3938 ParmVarDecl *New 3939 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3940 T, TInfo, StorageClass, 0); 3941 3942 if (D.isInvalidType()) 3943 New->setInvalidDecl(); 3944 3945 // Parameter declarators cannot be interface types. All ObjC objects are 3946 // passed by reference. 3947 if (T->isObjCInterfaceType()) { 3948 Diag(D.getIdentifierLoc(), 3949 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3950 New->setInvalidDecl(); 3951 } 3952 3953 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3954 if (D.getCXXScopeSpec().isSet()) { 3955 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3956 << D.getCXXScopeSpec().getRange(); 3957 New->setInvalidDecl(); 3958 } 3959 3960 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3961 // duration shall not be qualified by an address-space qualifier." 3962 // Since all parameters have automatic store duration, they can not have 3963 // an address space. 3964 if (T.getAddressSpace() != 0) { 3965 Diag(D.getIdentifierLoc(), 3966 diag::err_arg_with_address_space); 3967 New->setInvalidDecl(); 3968 } 3969 3970 3971 // Add the parameter declaration into this scope. 3972 S->AddDecl(DeclPtrTy::make(New)); 3973 if (II) 3974 IdResolver.AddDecl(New); 3975 3976 ProcessDeclAttributes(S, New, D); 3977 3978 if (New->hasAttr<BlocksAttr>()) { 3979 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3980 } 3981 return DeclPtrTy::make(New); 3982} 3983 3984void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3985 SourceLocation LocAfterDecls) { 3986 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3987 "Not a function declarator!"); 3988 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3989 3990 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3991 // for a K&R function. 3992 if (!FTI.hasPrototype) { 3993 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3994 --i; 3995 if (FTI.ArgInfo[i].Param == 0) { 3996 llvm::SmallString<256> Code; 3997 llvm::raw_svector_ostream(Code) << " int " 3998 << FTI.ArgInfo[i].Ident->getName() 3999 << ";\n"; 4000 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4001 << FTI.ArgInfo[i].Ident 4002 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4003 4004 // Implicitly declare the argument as type 'int' for lack of a better 4005 // type. 4006 DeclSpec DS; 4007 const char* PrevSpec; // unused 4008 unsigned DiagID; // unused 4009 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4010 PrevSpec, DiagID); 4011 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4012 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4013 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4014 } 4015 } 4016 } 4017} 4018 4019Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4020 Declarator &D) { 4021 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4022 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4023 "Not a function declarator!"); 4024 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4025 4026 if (FTI.hasPrototype) { 4027 // FIXME: Diagnose arguments without names in C. 4028 } 4029 4030 Scope *ParentScope = FnBodyScope->getParent(); 4031 4032 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4033 MultiTemplateParamsArg(*this), 4034 /*IsFunctionDefinition=*/true); 4035 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4036} 4037 4038static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4039 // Don't warn about invalid declarations. 4040 if (FD->isInvalidDecl()) 4041 return false; 4042 4043 // Or declarations that aren't global. 4044 if (!FD->isGlobal()) 4045 return false; 4046 4047 // Don't warn about C++ member functions. 4048 if (isa<CXXMethodDecl>(FD)) 4049 return false; 4050 4051 // Don't warn about 'main'. 4052 if (FD->isMain()) 4053 return false; 4054 4055 // Don't warn about inline functions. 4056 if (FD->isInlineSpecified()) 4057 return false; 4058 4059 // Don't warn about function templates. 4060 if (FD->getDescribedFunctionTemplate()) 4061 return false; 4062 4063 // Don't warn about function template specializations. 4064 if (FD->isFunctionTemplateSpecialization()) 4065 return false; 4066 4067 bool MissingPrototype = true; 4068 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4069 Prev; Prev = Prev->getPreviousDeclaration()) { 4070 // Ignore any declarations that occur in function or method 4071 // scope, because they aren't visible from the header. 4072 if (Prev->getDeclContext()->isFunctionOrMethod()) 4073 continue; 4074 4075 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4076 break; 4077 } 4078 4079 return MissingPrototype; 4080} 4081 4082Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4083 // Clear the last template instantiation error context. 4084 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4085 4086 if (!D) 4087 return D; 4088 FunctionDecl *FD = 0; 4089 4090 if (FunctionTemplateDecl *FunTmpl 4091 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4092 FD = FunTmpl->getTemplatedDecl(); 4093 else 4094 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4095 4096 CurFunctionNeedsScopeChecking = false; 4097 4098 // See if this is a redefinition. 4099 const FunctionDecl *Definition; 4100 if (FD->getBody(Definition)) { 4101 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4102 Diag(Definition->getLocation(), diag::note_previous_definition); 4103 } 4104 4105 // Builtin functions cannot be defined. 4106 if (unsigned BuiltinID = FD->getBuiltinID()) { 4107 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4108 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4109 FD->setInvalidDecl(); 4110 } 4111 } 4112 4113 // The return type of a function definition must be complete 4114 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4115 QualType ResultType = FD->getResultType(); 4116 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4117 !FD->isInvalidDecl() && 4118 RequireCompleteType(FD->getLocation(), ResultType, 4119 diag::err_func_def_incomplete_result)) 4120 FD->setInvalidDecl(); 4121 4122 // GNU warning -Wmissing-prototypes: 4123 // Warn if a global function is defined without a previous 4124 // prototype declaration. This warning is issued even if the 4125 // definition itself provides a prototype. The aim is to detect 4126 // global functions that fail to be declared in header files. 4127 if (ShouldWarnAboutMissingPrototype(FD)) 4128 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4129 4130 if (FnBodyScope) 4131 PushDeclContext(FnBodyScope, FD); 4132 4133 // Check the validity of our function parameters 4134 CheckParmsForFunctionDef(FD); 4135 4136 // Introduce our parameters into the function scope 4137 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4138 ParmVarDecl *Param = FD->getParamDecl(p); 4139 Param->setOwningFunction(FD); 4140 4141 // If this has an identifier, add it to the scope stack. 4142 if (Param->getIdentifier() && FnBodyScope) 4143 PushOnScopeChains(Param, FnBodyScope); 4144 } 4145 4146 // Checking attributes of current function definition 4147 // dllimport attribute. 4148 if (FD->getAttr<DLLImportAttr>() && 4149 (!FD->getAttr<DLLExportAttr>())) { 4150 // dllimport attribute cannot be applied to definition. 4151 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4152 Diag(FD->getLocation(), 4153 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4154 << "dllimport"; 4155 FD->setInvalidDecl(); 4156 return DeclPtrTy::make(FD); 4157 } else { 4158 // If a symbol previously declared dllimport is later defined, the 4159 // attribute is ignored in subsequent references, and a warning is 4160 // emitted. 4161 Diag(FD->getLocation(), 4162 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4163 << FD->getNameAsCString() << "dllimport"; 4164 } 4165 } 4166 return DeclPtrTy::make(FD); 4167} 4168 4169Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4170 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4171} 4172 4173Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4174 bool IsInstantiation) { 4175 Decl *dcl = D.getAs<Decl>(); 4176 Stmt *Body = BodyArg.takeAs<Stmt>(); 4177 4178 FunctionDecl *FD = 0; 4179 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4180 if (FunTmpl) 4181 FD = FunTmpl->getTemplatedDecl(); 4182 else 4183 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4184 4185 if (FD) { 4186 FD->setBody(Body); 4187 if (FD->isMain()) 4188 // C and C++ allow for main to automagically return 0. 4189 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4190 FD->setHasImplicitReturnZero(true); 4191 else 4192 CheckFallThroughForFunctionDef(FD, Body); 4193 4194 if (!FD->isInvalidDecl()) 4195 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4196 4197 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4198 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4199 4200 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4201 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4202 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4203 MD->setBody(Body); 4204 CheckFallThroughForFunctionDef(MD, Body); 4205 MD->setEndLoc(Body->getLocEnd()); 4206 4207 if (!MD->isInvalidDecl()) 4208 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4209 } else { 4210 Body->Destroy(Context); 4211 return DeclPtrTy(); 4212 } 4213 if (!IsInstantiation) 4214 PopDeclContext(); 4215 4216 // Verify and clean out per-function state. 4217 4218 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4219 4220 // Check goto/label use. 4221 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4222 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4223 LabelStmt *L = I->second; 4224 4225 // Verify that we have no forward references left. If so, there was a goto 4226 // or address of a label taken, but no definition of it. Label fwd 4227 // definitions are indicated with a null substmt. 4228 if (L->getSubStmt() != 0) 4229 continue; 4230 4231 // Emit error. 4232 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4233 4234 // At this point, we have gotos that use the bogus label. Stitch it into 4235 // the function body so that they aren't leaked and that the AST is well 4236 // formed. 4237 if (Body == 0) { 4238 // The whole function wasn't parsed correctly, just delete this. 4239 L->Destroy(Context); 4240 continue; 4241 } 4242 4243 // Otherwise, the body is valid: we want to stitch the label decl into the 4244 // function somewhere so that it is properly owned and so that the goto 4245 // has a valid target. Do this by creating a new compound stmt with the 4246 // label in it. 4247 4248 // Give the label a sub-statement. 4249 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4250 4251 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4252 cast<CXXTryStmt>(Body)->getTryBlock() : 4253 cast<CompoundStmt>(Body); 4254 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4255 Elements.push_back(L); 4256 Compound->setStmts(Context, &Elements[0], Elements.size()); 4257 } 4258 FunctionLabelMap.clear(); 4259 4260 if (!Body) return D; 4261 4262 // Verify that that gotos and switch cases don't jump into scopes illegally. 4263 if (CurFunctionNeedsScopeChecking) 4264 DiagnoseInvalidJumps(Body); 4265 4266 // C++ constructors that have function-try-blocks can't have return 4267 // statements in the handlers of that block. (C++ [except.handle]p14) 4268 // Verify this. 4269 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4270 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4271 4272 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4273 MarkBaseAndMemberDestructorsReferenced(Destructor); 4274 4275 // If any errors have occurred, clear out any temporaries that may have 4276 // been leftover. This ensures that these temporaries won't be picked up for 4277 // deletion in some later function. 4278 if (PP.getDiagnostics().hasErrorOccurred()) 4279 ExprTemporaries.clear(); 4280 4281 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4282 return D; 4283} 4284 4285/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4286/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4287NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4288 IdentifierInfo &II, Scope *S) { 4289 // Before we produce a declaration for an implicitly defined 4290 // function, see whether there was a locally-scoped declaration of 4291 // this name as a function or variable. If so, use that 4292 // (non-visible) declaration, and complain about it. 4293 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4294 = LocallyScopedExternalDecls.find(&II); 4295 if (Pos != LocallyScopedExternalDecls.end()) { 4296 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4297 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4298 return Pos->second; 4299 } 4300 4301 // Extension in C99. Legal in C90, but warn about it. 4302 if (II.getName().startswith("__builtin_")) 4303 Diag(Loc, diag::warn_builtin_unknown) << &II; 4304 else if (getLangOptions().C99) 4305 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4306 else 4307 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4308 4309 // Set a Declarator for the implicit definition: int foo(); 4310 const char *Dummy; 4311 DeclSpec DS; 4312 unsigned DiagID; 4313 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4314 Error = Error; // Silence warning. 4315 assert(!Error && "Error setting up implicit decl!"); 4316 Declarator D(DS, Declarator::BlockContext); 4317 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4318 0, 0, false, SourceLocation(), 4319 false, 0,0,0, Loc, Loc, D), 4320 SourceLocation()); 4321 D.SetIdentifier(&II, Loc); 4322 4323 // Insert this function into translation-unit scope. 4324 4325 DeclContext *PrevDC = CurContext; 4326 CurContext = Context.getTranslationUnitDecl(); 4327 4328 FunctionDecl *FD = 4329 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4330 FD->setImplicit(); 4331 4332 CurContext = PrevDC; 4333 4334 AddKnownFunctionAttributes(FD); 4335 4336 return FD; 4337} 4338 4339/// \brief Adds any function attributes that we know a priori based on 4340/// the declaration of this function. 4341/// 4342/// These attributes can apply both to implicitly-declared builtins 4343/// (like __builtin___printf_chk) or to library-declared functions 4344/// like NSLog or printf. 4345void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4346 if (FD->isInvalidDecl()) 4347 return; 4348 4349 // If this is a built-in function, map its builtin attributes to 4350 // actual attributes. 4351 if (unsigned BuiltinID = FD->getBuiltinID()) { 4352 // Handle printf-formatting attributes. 4353 unsigned FormatIdx; 4354 bool HasVAListArg; 4355 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4356 if (!FD->getAttr<FormatAttr>()) 4357 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4358 HasVAListArg ? 0 : FormatIdx + 2)); 4359 } 4360 4361 // Mark const if we don't care about errno and that is the only 4362 // thing preventing the function from being const. This allows 4363 // IRgen to use LLVM intrinsics for such functions. 4364 if (!getLangOptions().MathErrno && 4365 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4366 if (!FD->getAttr<ConstAttr>()) 4367 FD->addAttr(::new (Context) ConstAttr()); 4368 } 4369 4370 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4371 FD->addAttr(::new (Context) NoReturnAttr()); 4372 } 4373 4374 IdentifierInfo *Name = FD->getIdentifier(); 4375 if (!Name) 4376 return; 4377 if ((!getLangOptions().CPlusPlus && 4378 FD->getDeclContext()->isTranslationUnit()) || 4379 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4380 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4381 LinkageSpecDecl::lang_c)) { 4382 // Okay: this could be a libc/libm/Objective-C function we know 4383 // about. 4384 } else 4385 return; 4386 4387 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4388 // FIXME: NSLog and NSLogv should be target specific 4389 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4390 // FIXME: We known better than our headers. 4391 const_cast<FormatAttr *>(Format)->setType("printf"); 4392 } else 4393 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4394 Name->isStr("NSLogv") ? 0 : 2)); 4395 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4396 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4397 // target-specific builtins, perhaps? 4398 if (!FD->getAttr<FormatAttr>()) 4399 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4400 Name->isStr("vasprintf") ? 0 : 3)); 4401 } 4402} 4403 4404TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4405 TypeSourceInfo *TInfo) { 4406 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4407 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4408 4409 if (!TInfo) { 4410 assert(D.isInvalidType() && "no declarator info for valid type"); 4411 TInfo = Context.getTrivialTypeSourceInfo(T); 4412 } 4413 4414 // Scope manipulation handled by caller. 4415 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4416 D.getIdentifierLoc(), 4417 D.getIdentifier(), 4418 TInfo); 4419 4420 if (const TagType *TT = T->getAs<TagType>()) { 4421 TagDecl *TD = TT->getDecl(); 4422 4423 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4424 // keep track of the TypedefDecl. 4425 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4426 TD->setTypedefForAnonDecl(NewTD); 4427 } 4428 4429 if (D.isInvalidType()) 4430 NewTD->setInvalidDecl(); 4431 return NewTD; 4432} 4433 4434 4435/// \brief Determine whether a tag with a given kind is acceptable 4436/// as a redeclaration of the given tag declaration. 4437/// 4438/// \returns true if the new tag kind is acceptable, false otherwise. 4439bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4440 TagDecl::TagKind NewTag, 4441 SourceLocation NewTagLoc, 4442 const IdentifierInfo &Name) { 4443 // C++ [dcl.type.elab]p3: 4444 // The class-key or enum keyword present in the 4445 // elaborated-type-specifier shall agree in kind with the 4446 // declaration to which the name in theelaborated-type-specifier 4447 // refers. This rule also applies to the form of 4448 // elaborated-type-specifier that declares a class-name or 4449 // friend class since it can be construed as referring to the 4450 // definition of the class. Thus, in any 4451 // elaborated-type-specifier, the enum keyword shall be used to 4452 // refer to an enumeration (7.2), the union class-keyshall be 4453 // used to refer to a union (clause 9), and either the class or 4454 // struct class-key shall be used to refer to a class (clause 9) 4455 // declared using the class or struct class-key. 4456 TagDecl::TagKind OldTag = Previous->getTagKind(); 4457 if (OldTag == NewTag) 4458 return true; 4459 4460 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4461 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4462 // Warn about the struct/class tag mismatch. 4463 bool isTemplate = false; 4464 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4465 isTemplate = Record->getDescribedClassTemplate(); 4466 4467 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4468 << (NewTag == TagDecl::TK_class) 4469 << isTemplate << &Name 4470 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4471 OldTag == TagDecl::TK_class? "class" : "struct"); 4472 Diag(Previous->getLocation(), diag::note_previous_use); 4473 return true; 4474 } 4475 return false; 4476} 4477 4478/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4479/// former case, Name will be non-null. In the later case, Name will be null. 4480/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4481/// reference/declaration/definition of a tag. 4482Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4483 SourceLocation KWLoc, const CXXScopeSpec &SS, 4484 IdentifierInfo *Name, SourceLocation NameLoc, 4485 AttributeList *Attr, AccessSpecifier AS, 4486 MultiTemplateParamsArg TemplateParameterLists, 4487 bool &OwnedDecl, bool &IsDependent) { 4488 // If this is not a definition, it must have a name. 4489 assert((Name != 0 || TUK == TUK_Definition) && 4490 "Nameless record must be a definition!"); 4491 4492 OwnedDecl = false; 4493 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4494 4495 // FIXME: Check explicit specializations more carefully. 4496 bool isExplicitSpecialization = false; 4497 if (TUK != TUK_Reference) { 4498 if (TemplateParameterList *TemplateParams 4499 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4500 (TemplateParameterList**)TemplateParameterLists.get(), 4501 TemplateParameterLists.size(), 4502 isExplicitSpecialization)) { 4503 if (TemplateParams->size() > 0) { 4504 // This is a declaration or definition of a class template (which may 4505 // be a member of another template). 4506 OwnedDecl = false; 4507 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4508 SS, Name, NameLoc, Attr, 4509 TemplateParams, 4510 AS); 4511 TemplateParameterLists.release(); 4512 return Result.get(); 4513 } else { 4514 // The "template<>" header is extraneous. 4515 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4516 << ElaboratedType::getNameForTagKind(Kind) << Name; 4517 isExplicitSpecialization = true; 4518 } 4519 } 4520 4521 TemplateParameterLists.release(); 4522 } 4523 4524 DeclContext *SearchDC = CurContext; 4525 DeclContext *DC = CurContext; 4526 bool isStdBadAlloc = false; 4527 bool Invalid = false; 4528 4529 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4530 : NotForRedeclaration); 4531 4532 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4533 4534 if (Name && SS.isNotEmpty()) { 4535 // We have a nested-name tag ('struct foo::bar'). 4536 4537 // Check for invalid 'foo::'. 4538 if (SS.isInvalid()) { 4539 Name = 0; 4540 goto CreateNewDecl; 4541 } 4542 4543 // If this is a friend or a reference to a class in a dependent 4544 // context, don't try to make a decl for it. 4545 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4546 DC = computeDeclContext(SS, false); 4547 if (!DC) { 4548 IsDependent = true; 4549 return DeclPtrTy(); 4550 } 4551 } 4552 4553 if (RequireCompleteDeclContext(SS)) 4554 return DeclPtrTy::make((Decl *)0); 4555 4556 DC = computeDeclContext(SS, true); 4557 SearchDC = DC; 4558 // Look-up name inside 'foo::'. 4559 LookupQualifiedName(Previous, DC); 4560 4561 if (Previous.isAmbiguous()) 4562 return DeclPtrTy(); 4563 4564 // A tag 'foo::bar' must already exist. 4565 if (Previous.empty()) { 4566 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4567 Name = 0; 4568 Invalid = true; 4569 goto CreateNewDecl; 4570 } 4571 } else if (Name) { 4572 // If this is a named struct, check to see if there was a previous forward 4573 // declaration or definition. 4574 // FIXME: We're looking into outer scopes here, even when we 4575 // shouldn't be. Doing so can result in ambiguities that we 4576 // shouldn't be diagnosing. 4577 LookupName(Previous, S); 4578 4579 // Note: there used to be some attempt at recovery here. 4580 if (Previous.isAmbiguous()) 4581 return DeclPtrTy(); 4582 4583 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4584 // FIXME: This makes sure that we ignore the contexts associated 4585 // with C structs, unions, and enums when looking for a matching 4586 // tag declaration or definition. See the similar lookup tweak 4587 // in Sema::LookupName; is there a better way to deal with this? 4588 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4589 SearchDC = SearchDC->getParent(); 4590 } 4591 } 4592 4593 if (Previous.isSingleResult() && 4594 Previous.getFoundDecl()->isTemplateParameter()) { 4595 // Maybe we will complain about the shadowed template parameter. 4596 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4597 // Just pretend that we didn't see the previous declaration. 4598 Previous.clear(); 4599 } 4600 4601 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4602 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4603 // This is a declaration of or a reference to "std::bad_alloc". 4604 isStdBadAlloc = true; 4605 4606 if (Previous.empty() && StdBadAlloc) { 4607 // std::bad_alloc has been implicitly declared (but made invisible to 4608 // name lookup). Fill in this implicit declaration as the previous 4609 // declaration, so that the declarations get chained appropriately. 4610 Previous.addDecl(StdBadAlloc); 4611 } 4612 } 4613 4614 if (!Previous.empty()) { 4615 assert(Previous.isSingleResult()); 4616 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4617 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4618 // If this is a use of a previous tag, or if the tag is already declared 4619 // in the same scope (so that the definition/declaration completes or 4620 // rementions the tag), reuse the decl. 4621 if (TUK == TUK_Reference || TUK == TUK_Friend || 4622 isDeclInScope(PrevDecl, SearchDC, S)) { 4623 // Make sure that this wasn't declared as an enum and now used as a 4624 // struct or something similar. 4625 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4626 bool SafeToContinue 4627 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4628 Kind != TagDecl::TK_enum); 4629 if (SafeToContinue) 4630 Diag(KWLoc, diag::err_use_with_wrong_tag) 4631 << Name 4632 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4633 PrevTagDecl->getKindName()); 4634 else 4635 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4636 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4637 4638 if (SafeToContinue) 4639 Kind = PrevTagDecl->getTagKind(); 4640 else { 4641 // Recover by making this an anonymous redefinition. 4642 Name = 0; 4643 Previous.clear(); 4644 Invalid = true; 4645 } 4646 } 4647 4648 if (!Invalid) { 4649 // If this is a use, just return the declaration we found. 4650 4651 // FIXME: In the future, return a variant or some other clue 4652 // for the consumer of this Decl to know it doesn't own it. 4653 // For our current ASTs this shouldn't be a problem, but will 4654 // need to be changed with DeclGroups. 4655 if (TUK == TUK_Reference || TUK == TUK_Friend) 4656 return DeclPtrTy::make(PrevTagDecl); 4657 4658 // Diagnose attempts to redefine a tag. 4659 if (TUK == TUK_Definition) { 4660 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4661 // If we're defining a specialization and the previous definition 4662 // is from an implicit instantiation, don't emit an error 4663 // here; we'll catch this in the general case below. 4664 if (!isExplicitSpecialization || 4665 !isa<CXXRecordDecl>(Def) || 4666 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4667 == TSK_ExplicitSpecialization) { 4668 Diag(NameLoc, diag::err_redefinition) << Name; 4669 Diag(Def->getLocation(), diag::note_previous_definition); 4670 // If this is a redefinition, recover by making this 4671 // struct be anonymous, which will make any later 4672 // references get the previous definition. 4673 Name = 0; 4674 Previous.clear(); 4675 Invalid = true; 4676 } 4677 } else { 4678 // If the type is currently being defined, complain 4679 // about a nested redefinition. 4680 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4681 if (Tag->isBeingDefined()) { 4682 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4683 Diag(PrevTagDecl->getLocation(), 4684 diag::note_previous_definition); 4685 Name = 0; 4686 Previous.clear(); 4687 Invalid = true; 4688 } 4689 } 4690 4691 // Okay, this is definition of a previously declared or referenced 4692 // tag PrevDecl. We're going to create a new Decl for it. 4693 } 4694 } 4695 // If we get here we have (another) forward declaration or we 4696 // have a definition. Just create a new decl. 4697 4698 } else { 4699 // If we get here, this is a definition of a new tag type in a nested 4700 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4701 // new decl/type. We set PrevDecl to NULL so that the entities 4702 // have distinct types. 4703 Previous.clear(); 4704 } 4705 // If we get here, we're going to create a new Decl. If PrevDecl 4706 // is non-NULL, it's a definition of the tag declared by 4707 // PrevDecl. If it's NULL, we have a new definition. 4708 } else { 4709 // PrevDecl is a namespace, template, or anything else 4710 // that lives in the IDNS_Tag identifier namespace. 4711 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4712 // The tag name clashes with a namespace name, issue an error and 4713 // recover by making this tag be anonymous. 4714 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4715 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4716 Name = 0; 4717 Previous.clear(); 4718 Invalid = true; 4719 } else { 4720 // The existing declaration isn't relevant to us; we're in a 4721 // new scope, so clear out the previous declaration. 4722 Previous.clear(); 4723 } 4724 } 4725 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4726 // C++ [basic.scope.pdecl]p5: 4727 // -- for an elaborated-type-specifier of the form 4728 // 4729 // class-key identifier 4730 // 4731 // if the elaborated-type-specifier is used in the 4732 // decl-specifier-seq or parameter-declaration-clause of a 4733 // function defined in namespace scope, the identifier is 4734 // declared as a class-name in the namespace that contains 4735 // the declaration; otherwise, except as a friend 4736 // declaration, the identifier is declared in the smallest 4737 // non-class, non-function-prototype scope that contains the 4738 // declaration. 4739 // 4740 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4741 // C structs and unions. 4742 // 4743 // It is an error in C++ to declare (rather than define) an enum 4744 // type, including via an elaborated type specifier. We'll 4745 // diagnose that later; for now, declare the enum in the same 4746 // scope as we would have picked for any other tag type. 4747 // 4748 // GNU C also supports this behavior as part of its incomplete 4749 // enum types extension, while GNU C++ does not. 4750 // 4751 // Find the context where we'll be declaring the tag. 4752 // FIXME: We would like to maintain the current DeclContext as the 4753 // lexical context, 4754 while (SearchDC->isRecord()) 4755 SearchDC = SearchDC->getParent(); 4756 4757 // Find the scope where we'll be declaring the tag. 4758 while (S->isClassScope() || 4759 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4760 ((S->getFlags() & Scope::DeclScope) == 0) || 4761 (S->getEntity() && 4762 ((DeclContext *)S->getEntity())->isTransparentContext())) 4763 S = S->getParent(); 4764 4765 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4766 // C++ [namespace.memdef]p3: 4767 // If a friend declaration in a non-local class first declares a 4768 // class or function, the friend class or function is a member of 4769 // the innermost enclosing namespace. 4770 while (!SearchDC->isFileContext()) 4771 SearchDC = SearchDC->getParent(); 4772 4773 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4774 while (S->getEntity() != SearchDC) 4775 S = S->getParent(); 4776 } 4777 4778CreateNewDecl: 4779 4780 TagDecl *PrevDecl = 0; 4781 if (Previous.isSingleResult()) 4782 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4783 4784 // If there is an identifier, use the location of the identifier as the 4785 // location of the decl, otherwise use the location of the struct/union 4786 // keyword. 4787 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4788 4789 // Otherwise, create a new declaration. If there is a previous 4790 // declaration of the same entity, the two will be linked via 4791 // PrevDecl. 4792 TagDecl *New; 4793 4794 if (Kind == TagDecl::TK_enum) { 4795 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4796 // enum X { A, B, C } D; D should chain to X. 4797 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4798 cast_or_null<EnumDecl>(PrevDecl)); 4799 // If this is an undefined enum, warn. 4800 if (TUK != TUK_Definition && !Invalid) { 4801 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4802 : diag::ext_forward_ref_enum; 4803 Diag(Loc, DK); 4804 } 4805 } else { 4806 // struct/union/class 4807 4808 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4809 // struct X { int A; } D; D should chain to X. 4810 if (getLangOptions().CPlusPlus) { 4811 // FIXME: Look for a way to use RecordDecl for simple structs. 4812 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4813 cast_or_null<CXXRecordDecl>(PrevDecl)); 4814 4815 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4816 StdBadAlloc = cast<CXXRecordDecl>(New); 4817 } else 4818 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4819 cast_or_null<RecordDecl>(PrevDecl)); 4820 } 4821 4822 if (Kind != TagDecl::TK_enum) { 4823 // Handle #pragma pack: if the #pragma pack stack has non-default 4824 // alignment, make up a packed attribute for this decl. These 4825 // attributes are checked when the ASTContext lays out the 4826 // structure. 4827 // 4828 // It is important for implementing the correct semantics that this 4829 // happen here (in act on tag decl). The #pragma pack stack is 4830 // maintained as a result of parser callbacks which can occur at 4831 // many points during the parsing of a struct declaration (because 4832 // the #pragma tokens are effectively skipped over during the 4833 // parsing of the struct). 4834 if (unsigned Alignment = getPragmaPackAlignment()) 4835 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4836 } 4837 4838 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4839 // C++ [dcl.typedef]p3: 4840 // [...] Similarly, in a given scope, a class or enumeration 4841 // shall not be declared with the same name as a typedef-name 4842 // that is declared in that scope and refers to a type other 4843 // than the class or enumeration itself. 4844 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4845 ForRedeclaration); 4846 LookupName(Lookup, S); 4847 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4848 NamedDecl *PrevTypedefNamed = PrevTypedef; 4849 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4850 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4851 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4852 Diag(Loc, diag::err_tag_definition_of_typedef) 4853 << Context.getTypeDeclType(New) 4854 << PrevTypedef->getUnderlyingType(); 4855 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4856 Invalid = true; 4857 } 4858 } 4859 4860 // If this is a specialization of a member class (of a class template), 4861 // check the specialization. 4862 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4863 Invalid = true; 4864 4865 if (Invalid) 4866 New->setInvalidDecl(); 4867 4868 if (Attr) 4869 ProcessDeclAttributeList(S, New, Attr); 4870 4871 // If we're declaring or defining a tag in function prototype scope 4872 // in C, note that this type can only be used within the function. 4873 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4874 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4875 4876 // Set the lexical context. If the tag has a C++ scope specifier, the 4877 // lexical context will be different from the semantic context. 4878 New->setLexicalDeclContext(CurContext); 4879 4880 // Mark this as a friend decl if applicable. 4881 if (TUK == TUK_Friend) 4882 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4883 4884 // Set the access specifier. 4885 if (!Invalid && TUK != TUK_Friend) 4886 SetMemberAccessSpecifier(New, PrevDecl, AS); 4887 4888 if (TUK == TUK_Definition) 4889 New->startDefinition(); 4890 4891 // If this has an identifier, add it to the scope stack. 4892 if (TUK == TUK_Friend) { 4893 // We might be replacing an existing declaration in the lookup tables; 4894 // if so, borrow its access specifier. 4895 if (PrevDecl) 4896 New->setAccess(PrevDecl->getAccess()); 4897 4898 // Friend tag decls are visible in fairly strange ways. 4899 if (!CurContext->isDependentContext()) { 4900 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4901 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4902 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4903 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4904 } 4905 } else if (Name) { 4906 S = getNonFieldDeclScope(S); 4907 PushOnScopeChains(New, S); 4908 } else { 4909 CurContext->addDecl(New); 4910 } 4911 4912 // If this is the C FILE type, notify the AST context. 4913 if (IdentifierInfo *II = New->getIdentifier()) 4914 if (!New->isInvalidDecl() && 4915 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4916 II->isStr("FILE")) 4917 Context.setFILEDecl(New); 4918 4919 OwnedDecl = true; 4920 return DeclPtrTy::make(New); 4921} 4922 4923void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4924 AdjustDeclIfTemplate(TagD); 4925 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4926 4927 // Enter the tag context. 4928 PushDeclContext(S, Tag); 4929 4930 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4931 FieldCollector->StartClass(); 4932 4933 if (Record->getIdentifier()) { 4934 // C++ [class]p2: 4935 // [...] The class-name is also inserted into the scope of the 4936 // class itself; this is known as the injected-class-name. For 4937 // purposes of access checking, the injected-class-name is treated 4938 // as if it were a public member name. 4939 CXXRecordDecl *InjectedClassName 4940 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4941 CurContext, Record->getLocation(), 4942 Record->getIdentifier(), 4943 Record->getTagKeywordLoc(), 4944 Record); 4945 InjectedClassName->setImplicit(); 4946 InjectedClassName->setAccess(AS_public); 4947 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4948 InjectedClassName->setDescribedClassTemplate(Template); 4949 PushOnScopeChains(InjectedClassName, S); 4950 assert(InjectedClassName->isInjectedClassName() && 4951 "Broken injected-class-name"); 4952 } 4953 } 4954} 4955 4956void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4957 SourceLocation RBraceLoc) { 4958 AdjustDeclIfTemplate(TagD); 4959 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4960 Tag->setRBraceLoc(RBraceLoc); 4961 4962 if (isa<CXXRecordDecl>(Tag)) 4963 FieldCollector->FinishClass(); 4964 4965 // Exit this scope of this tag's definition. 4966 PopDeclContext(); 4967 4968 // Notify the consumer that we've defined a tag. 4969 Consumer.HandleTagDeclDefinition(Tag); 4970} 4971 4972// Note that FieldName may be null for anonymous bitfields. 4973bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4974 QualType FieldTy, const Expr *BitWidth, 4975 bool *ZeroWidth) { 4976 // Default to true; that shouldn't confuse checks for emptiness 4977 if (ZeroWidth) 4978 *ZeroWidth = true; 4979 4980 // C99 6.7.2.1p4 - verify the field type. 4981 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4982 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4983 // Handle incomplete types with specific error. 4984 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4985 return true; 4986 if (FieldName) 4987 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4988 << FieldName << FieldTy << BitWidth->getSourceRange(); 4989 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4990 << FieldTy << BitWidth->getSourceRange(); 4991 } 4992 4993 // If the bit-width is type- or value-dependent, don't try to check 4994 // it now. 4995 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4996 return false; 4997 4998 llvm::APSInt Value; 4999 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5000 return true; 5001 5002 if (Value != 0 && ZeroWidth) 5003 *ZeroWidth = false; 5004 5005 // Zero-width bitfield is ok for anonymous field. 5006 if (Value == 0 && FieldName) 5007 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5008 5009 if (Value.isSigned() && Value.isNegative()) { 5010 if (FieldName) 5011 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5012 << FieldName << Value.toString(10); 5013 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5014 << Value.toString(10); 5015 } 5016 5017 if (!FieldTy->isDependentType()) { 5018 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5019 if (Value.getZExtValue() > TypeSize) { 5020 if (FieldName) 5021 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5022 << FieldName << (unsigned)TypeSize; 5023 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5024 << (unsigned)TypeSize; 5025 } 5026 } 5027 5028 return false; 5029} 5030 5031/// ActOnField - Each field of a struct/union/class is passed into this in order 5032/// to create a FieldDecl object for it. 5033Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5034 SourceLocation DeclStart, 5035 Declarator &D, ExprTy *BitfieldWidth) { 5036 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5037 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5038 AS_public); 5039 return DeclPtrTy::make(Res); 5040} 5041 5042/// HandleField - Analyze a field of a C struct or a C++ data member. 5043/// 5044FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5045 SourceLocation DeclStart, 5046 Declarator &D, Expr *BitWidth, 5047 AccessSpecifier AS) { 5048 IdentifierInfo *II = D.getIdentifier(); 5049 SourceLocation Loc = DeclStart; 5050 if (II) Loc = D.getIdentifierLoc(); 5051 5052 TypeSourceInfo *TInfo = 0; 5053 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5054 if (getLangOptions().CPlusPlus) 5055 CheckExtraCXXDefaultArguments(D); 5056 5057 DiagnoseFunctionSpecifiers(D); 5058 5059 if (D.getDeclSpec().isThreadSpecified()) 5060 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5061 5062 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5063 ForRedeclaration); 5064 5065 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5066 // Maybe we will complain about the shadowed template parameter. 5067 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5068 // Just pretend that we didn't see the previous declaration. 5069 PrevDecl = 0; 5070 } 5071 5072 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5073 PrevDecl = 0; 5074 5075 bool Mutable 5076 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5077 SourceLocation TSSL = D.getSourceRange().getBegin(); 5078 FieldDecl *NewFD 5079 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5080 AS, PrevDecl, &D); 5081 if (NewFD->isInvalidDecl() && PrevDecl) { 5082 // Don't introduce NewFD into scope; there's already something 5083 // with the same name in the same scope. 5084 } else if (II) { 5085 PushOnScopeChains(NewFD, S); 5086 } else 5087 Record->addDecl(NewFD); 5088 5089 return NewFD; 5090} 5091 5092/// \brief Build a new FieldDecl and check its well-formedness. 5093/// 5094/// This routine builds a new FieldDecl given the fields name, type, 5095/// record, etc. \p PrevDecl should refer to any previous declaration 5096/// with the same name and in the same scope as the field to be 5097/// created. 5098/// 5099/// \returns a new FieldDecl. 5100/// 5101/// \todo The Declarator argument is a hack. It will be removed once 5102FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5103 TypeSourceInfo *TInfo, 5104 RecordDecl *Record, SourceLocation Loc, 5105 bool Mutable, Expr *BitWidth, 5106 SourceLocation TSSL, 5107 AccessSpecifier AS, NamedDecl *PrevDecl, 5108 Declarator *D) { 5109 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5110 bool InvalidDecl = false; 5111 if (D) InvalidDecl = D->isInvalidType(); 5112 5113 // If we receive a broken type, recover by assuming 'int' and 5114 // marking this declaration as invalid. 5115 if (T.isNull()) { 5116 InvalidDecl = true; 5117 T = Context.IntTy; 5118 } 5119 5120 QualType EltTy = Context.getBaseElementType(T); 5121 if (!EltTy->isDependentType() && 5122 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5123 InvalidDecl = true; 5124 5125 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5126 // than a variably modified type. 5127 if (!InvalidDecl && T->isVariablyModifiedType()) { 5128 bool SizeIsNegative; 5129 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5130 SizeIsNegative); 5131 if (!FixedTy.isNull()) { 5132 Diag(Loc, diag::warn_illegal_constant_array_size); 5133 T = FixedTy; 5134 } else { 5135 if (SizeIsNegative) 5136 Diag(Loc, diag::err_typecheck_negative_array_size); 5137 else 5138 Diag(Loc, diag::err_typecheck_field_variable_size); 5139 InvalidDecl = true; 5140 } 5141 } 5142 5143 // Fields can not have abstract class types 5144 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5145 diag::err_abstract_type_in_decl, 5146 AbstractFieldType)) 5147 InvalidDecl = true; 5148 5149 bool ZeroWidth = false; 5150 // If this is declared as a bit-field, check the bit-field. 5151 if (!InvalidDecl && BitWidth && 5152 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5153 InvalidDecl = true; 5154 DeleteExpr(BitWidth); 5155 BitWidth = 0; 5156 ZeroWidth = false; 5157 } 5158 5159 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5160 BitWidth, Mutable); 5161 if (InvalidDecl) 5162 NewFD->setInvalidDecl(); 5163 5164 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5165 Diag(Loc, diag::err_duplicate_member) << II; 5166 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5167 NewFD->setInvalidDecl(); 5168 } 5169 5170 if (getLangOptions().CPlusPlus) { 5171 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5172 5173 if (!T->isPODType()) 5174 CXXRecord->setPOD(false); 5175 if (!ZeroWidth) 5176 CXXRecord->setEmpty(false); 5177 5178 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5179 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5180 5181 if (!RDecl->hasTrivialConstructor()) 5182 CXXRecord->setHasTrivialConstructor(false); 5183 if (!RDecl->hasTrivialCopyConstructor()) 5184 CXXRecord->setHasTrivialCopyConstructor(false); 5185 if (!RDecl->hasTrivialCopyAssignment()) 5186 CXXRecord->setHasTrivialCopyAssignment(false); 5187 if (!RDecl->hasTrivialDestructor()) 5188 CXXRecord->setHasTrivialDestructor(false); 5189 5190 // C++ 9.5p1: An object of a class with a non-trivial 5191 // constructor, a non-trivial copy constructor, a non-trivial 5192 // destructor, or a non-trivial copy assignment operator 5193 // cannot be a member of a union, nor can an array of such 5194 // objects. 5195 // TODO: C++0x alters this restriction significantly. 5196 if (Record->isUnion()) { 5197 // We check for copy constructors before constructors 5198 // because otherwise we'll never get complaints about 5199 // copy constructors. 5200 5201 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5202 5203 CXXSpecialMember member; 5204 if (!RDecl->hasTrivialCopyConstructor()) 5205 member = CXXCopyConstructor; 5206 else if (!RDecl->hasTrivialConstructor()) 5207 member = CXXDefaultConstructor; 5208 else if (!RDecl->hasTrivialCopyAssignment()) 5209 member = CXXCopyAssignment; 5210 else if (!RDecl->hasTrivialDestructor()) 5211 member = CXXDestructor; 5212 else 5213 member = invalid; 5214 5215 if (member != invalid) { 5216 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5217 DiagnoseNontrivial(RT, member); 5218 NewFD->setInvalidDecl(); 5219 } 5220 } 5221 } 5222 } 5223 5224 // FIXME: We need to pass in the attributes given an AST 5225 // representation, not a parser representation. 5226 if (D) 5227 // FIXME: What to pass instead of TUScope? 5228 ProcessDeclAttributes(TUScope, NewFD, *D); 5229 5230 if (T.isObjCGCWeak()) 5231 Diag(Loc, diag::warn_attribute_weak_on_field); 5232 5233 NewFD->setAccess(AS); 5234 5235 // C++ [dcl.init.aggr]p1: 5236 // An aggregate is an array or a class (clause 9) with [...] no 5237 // private or protected non-static data members (clause 11). 5238 // A POD must be an aggregate. 5239 if (getLangOptions().CPlusPlus && 5240 (AS == AS_private || AS == AS_protected)) { 5241 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5242 CXXRecord->setAggregate(false); 5243 CXXRecord->setPOD(false); 5244 } 5245 5246 return NewFD; 5247} 5248 5249/// DiagnoseNontrivial - Given that a class has a non-trivial 5250/// special member, figure out why. 5251void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5252 QualType QT(T, 0U); 5253 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5254 5255 // Check whether the member was user-declared. 5256 switch (member) { 5257 case CXXDefaultConstructor: 5258 if (RD->hasUserDeclaredConstructor()) { 5259 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5260 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5261 const FunctionDecl *body = 0; 5262 ci->getBody(body); 5263 if (!body || 5264 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5265 SourceLocation CtorLoc = ci->getLocation(); 5266 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5267 return; 5268 } 5269 } 5270 5271 assert(0 && "found no user-declared constructors"); 5272 return; 5273 } 5274 break; 5275 5276 case CXXCopyConstructor: 5277 if (RD->hasUserDeclaredCopyConstructor()) { 5278 SourceLocation CtorLoc = 5279 RD->getCopyConstructor(Context, 0)->getLocation(); 5280 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5281 return; 5282 } 5283 break; 5284 5285 case CXXCopyAssignment: 5286 if (RD->hasUserDeclaredCopyAssignment()) { 5287 // FIXME: this should use the location of the copy 5288 // assignment, not the type. 5289 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5290 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5291 return; 5292 } 5293 break; 5294 5295 case CXXDestructor: 5296 if (RD->hasUserDeclaredDestructor()) { 5297 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5298 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5299 return; 5300 } 5301 break; 5302 } 5303 5304 typedef CXXRecordDecl::base_class_iterator base_iter; 5305 5306 // Virtual bases and members inhibit trivial copying/construction, 5307 // but not trivial destruction. 5308 if (member != CXXDestructor) { 5309 // Check for virtual bases. vbases includes indirect virtual bases, 5310 // so we just iterate through the direct bases. 5311 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5312 if (bi->isVirtual()) { 5313 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5314 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5315 return; 5316 } 5317 5318 // Check for virtual methods. 5319 typedef CXXRecordDecl::method_iterator meth_iter; 5320 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5321 ++mi) { 5322 if (mi->isVirtual()) { 5323 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5324 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5325 return; 5326 } 5327 } 5328 } 5329 5330 bool (CXXRecordDecl::*hasTrivial)() const; 5331 switch (member) { 5332 case CXXDefaultConstructor: 5333 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5334 case CXXCopyConstructor: 5335 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5336 case CXXCopyAssignment: 5337 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5338 case CXXDestructor: 5339 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5340 default: 5341 assert(0 && "unexpected special member"); return; 5342 } 5343 5344 // Check for nontrivial bases (and recurse). 5345 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5346 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5347 assert(BaseRT && "Don't know how to handle dependent bases"); 5348 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5349 if (!(BaseRecTy->*hasTrivial)()) { 5350 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5351 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5352 DiagnoseNontrivial(BaseRT, member); 5353 return; 5354 } 5355 } 5356 5357 // Check for nontrivial members (and recurse). 5358 typedef RecordDecl::field_iterator field_iter; 5359 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5360 ++fi) { 5361 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5362 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5363 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5364 5365 if (!(EltRD->*hasTrivial)()) { 5366 SourceLocation FLoc = (*fi)->getLocation(); 5367 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5368 DiagnoseNontrivial(EltRT, member); 5369 return; 5370 } 5371 } 5372 } 5373 5374 assert(0 && "found no explanation for non-trivial member"); 5375} 5376 5377/// TranslateIvarVisibility - Translate visibility from a token ID to an 5378/// AST enum value. 5379static ObjCIvarDecl::AccessControl 5380TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5381 switch (ivarVisibility) { 5382 default: assert(0 && "Unknown visitibility kind"); 5383 case tok::objc_private: return ObjCIvarDecl::Private; 5384 case tok::objc_public: return ObjCIvarDecl::Public; 5385 case tok::objc_protected: return ObjCIvarDecl::Protected; 5386 case tok::objc_package: return ObjCIvarDecl::Package; 5387 } 5388} 5389 5390/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5391/// in order to create an IvarDecl object for it. 5392Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5393 SourceLocation DeclStart, 5394 DeclPtrTy IntfDecl, 5395 Declarator &D, ExprTy *BitfieldWidth, 5396 tok::ObjCKeywordKind Visibility) { 5397 5398 IdentifierInfo *II = D.getIdentifier(); 5399 Expr *BitWidth = (Expr*)BitfieldWidth; 5400 SourceLocation Loc = DeclStart; 5401 if (II) Loc = D.getIdentifierLoc(); 5402 5403 // FIXME: Unnamed fields can be handled in various different ways, for 5404 // example, unnamed unions inject all members into the struct namespace! 5405 5406 TypeSourceInfo *TInfo = 0; 5407 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5408 5409 if (BitWidth) { 5410 // 6.7.2.1p3, 6.7.2.1p4 5411 if (VerifyBitField(Loc, II, T, BitWidth)) { 5412 D.setInvalidType(); 5413 DeleteExpr(BitWidth); 5414 BitWidth = 0; 5415 } 5416 } else { 5417 // Not a bitfield. 5418 5419 // validate II. 5420 5421 } 5422 5423 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5424 // than a variably modified type. 5425 if (T->isVariablyModifiedType()) { 5426 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5427 D.setInvalidType(); 5428 } 5429 5430 // Get the visibility (access control) for this ivar. 5431 ObjCIvarDecl::AccessControl ac = 5432 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5433 : ObjCIvarDecl::None; 5434 // Must set ivar's DeclContext to its enclosing interface. 5435 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5436 DeclContext *EnclosingContext; 5437 if (ObjCImplementationDecl *IMPDecl = 5438 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5439 // Case of ivar declared in an implementation. Context is that of its class. 5440 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5441 assert(IDecl && "No class- ActOnIvar"); 5442 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5443 } else 5444 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5445 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5446 5447 // Construct the decl. 5448 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5449 EnclosingContext, Loc, II, T, 5450 TInfo, ac, (Expr *)BitfieldWidth); 5451 5452 if (II) { 5453 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5454 ForRedeclaration); 5455 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5456 && !isa<TagDecl>(PrevDecl)) { 5457 Diag(Loc, diag::err_duplicate_member) << II; 5458 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5459 NewID->setInvalidDecl(); 5460 } 5461 } 5462 5463 // Process attributes attached to the ivar. 5464 ProcessDeclAttributes(S, NewID, D); 5465 5466 if (D.isInvalidType()) 5467 NewID->setInvalidDecl(); 5468 5469 if (II) { 5470 // FIXME: When interfaces are DeclContexts, we'll need to add 5471 // these to the interface. 5472 S->AddDecl(DeclPtrTy::make(NewID)); 5473 IdResolver.AddDecl(NewID); 5474 } 5475 5476 return DeclPtrTy::make(NewID); 5477} 5478 5479void Sema::ActOnFields(Scope* S, 5480 SourceLocation RecLoc, DeclPtrTy RecDecl, 5481 DeclPtrTy *Fields, unsigned NumFields, 5482 SourceLocation LBrac, SourceLocation RBrac, 5483 AttributeList *Attr) { 5484 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5485 assert(EnclosingDecl && "missing record or interface decl"); 5486 5487 // If the decl this is being inserted into is invalid, then it may be a 5488 // redeclaration or some other bogus case. Don't try to add fields to it. 5489 if (EnclosingDecl->isInvalidDecl()) { 5490 // FIXME: Deallocate fields? 5491 return; 5492 } 5493 5494 5495 // Verify that all the fields are okay. 5496 unsigned NumNamedMembers = 0; 5497 llvm::SmallVector<FieldDecl*, 32> RecFields; 5498 5499 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5500 for (unsigned i = 0; i != NumFields; ++i) { 5501 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5502 5503 // Get the type for the field. 5504 Type *FDTy = FD->getType().getTypePtr(); 5505 5506 if (!FD->isAnonymousStructOrUnion()) { 5507 // Remember all fields written by the user. 5508 RecFields.push_back(FD); 5509 } 5510 5511 // If the field is already invalid for some reason, don't emit more 5512 // diagnostics about it. 5513 if (FD->isInvalidDecl()) { 5514 EnclosingDecl->setInvalidDecl(); 5515 continue; 5516 } 5517 5518 // C99 6.7.2.1p2: 5519 // A structure or union shall not contain a member with 5520 // incomplete or function type (hence, a structure shall not 5521 // contain an instance of itself, but may contain a pointer to 5522 // an instance of itself), except that the last member of a 5523 // structure with more than one named member may have incomplete 5524 // array type; such a structure (and any union containing, 5525 // possibly recursively, a member that is such a structure) 5526 // shall not be a member of a structure or an element of an 5527 // array. 5528 if (FDTy->isFunctionType()) { 5529 // Field declared as a function. 5530 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5531 << FD->getDeclName(); 5532 FD->setInvalidDecl(); 5533 EnclosingDecl->setInvalidDecl(); 5534 continue; 5535 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5536 Record && Record->isStruct()) { 5537 // Flexible array member. 5538 if (NumNamedMembers < 1) { 5539 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5540 << FD->getDeclName(); 5541 FD->setInvalidDecl(); 5542 EnclosingDecl->setInvalidDecl(); 5543 continue; 5544 } 5545 // Okay, we have a legal flexible array member at the end of the struct. 5546 if (Record) 5547 Record->setHasFlexibleArrayMember(true); 5548 } else if (!FDTy->isDependentType() && 5549 RequireCompleteType(FD->getLocation(), FD->getType(), 5550 diag::err_field_incomplete)) { 5551 // Incomplete type 5552 FD->setInvalidDecl(); 5553 EnclosingDecl->setInvalidDecl(); 5554 continue; 5555 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5556 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5557 // If this is a member of a union, then entire union becomes "flexible". 5558 if (Record && Record->isUnion()) { 5559 Record->setHasFlexibleArrayMember(true); 5560 } else { 5561 // If this is a struct/class and this is not the last element, reject 5562 // it. Note that GCC supports variable sized arrays in the middle of 5563 // structures. 5564 if (i != NumFields-1) 5565 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5566 << FD->getDeclName() << FD->getType(); 5567 else { 5568 // We support flexible arrays at the end of structs in 5569 // other structs as an extension. 5570 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5571 << FD->getDeclName(); 5572 if (Record) 5573 Record->setHasFlexibleArrayMember(true); 5574 } 5575 } 5576 } 5577 if (Record && FDTTy->getDecl()->hasObjectMember()) 5578 Record->setHasObjectMember(true); 5579 } else if (FDTy->isObjCInterfaceType()) { 5580 /// A field cannot be an Objective-c object 5581 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5582 FD->setInvalidDecl(); 5583 EnclosingDecl->setInvalidDecl(); 5584 continue; 5585 } else if (getLangOptions().ObjC1 && 5586 getLangOptions().getGCMode() != LangOptions::NonGC && 5587 Record && 5588 (FD->getType()->isObjCObjectPointerType() || 5589 FD->getType().isObjCGCStrong())) 5590 Record->setHasObjectMember(true); 5591 // Keep track of the number of named members. 5592 if (FD->getIdentifier()) 5593 ++NumNamedMembers; 5594 } 5595 5596 // Okay, we successfully defined 'Record'. 5597 if (Record) { 5598 Record->completeDefinition(Context); 5599 } else { 5600 ObjCIvarDecl **ClsFields = 5601 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5602 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5603 ID->setIVarList(ClsFields, RecFields.size(), Context); 5604 ID->setLocEnd(RBrac); 5605 // Add ivar's to class's DeclContext. 5606 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5607 ClsFields[i]->setLexicalDeclContext(ID); 5608 ID->addDecl(ClsFields[i]); 5609 } 5610 // Must enforce the rule that ivars in the base classes may not be 5611 // duplicates. 5612 if (ID->getSuperClass()) { 5613 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5614 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5615 ObjCIvarDecl* Ivar = (*IVI); 5616 5617 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5618 ObjCIvarDecl* prevIvar = 5619 ID->getSuperClass()->lookupInstanceVariable(II); 5620 if (prevIvar) { 5621 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5622 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5623 } 5624 } 5625 } 5626 } 5627 } else if (ObjCImplementationDecl *IMPDecl = 5628 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5629 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5630 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5631 // Ivar declared in @implementation never belongs to the implementation. 5632 // Only it is in implementation's lexical context. 5633 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5634 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5635 } 5636 } 5637 5638 if (Attr) 5639 ProcessDeclAttributeList(S, Record, Attr); 5640} 5641 5642EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5643 EnumConstantDecl *LastEnumConst, 5644 SourceLocation IdLoc, 5645 IdentifierInfo *Id, 5646 ExprArg val) { 5647 Expr *Val = (Expr *)val.get(); 5648 5649 llvm::APSInt EnumVal(32); 5650 QualType EltTy; 5651 if (Val) { 5652 if (Val->isTypeDependent()) 5653 EltTy = Context.DependentTy; 5654 else { 5655 // Make sure to promote the operand type to int. 5656 UsualUnaryConversions(Val); 5657 if (Val != val.get()) { 5658 val.release(); 5659 val = Val; 5660 } 5661 5662 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5663 SourceLocation ExpLoc; 5664 if (!Val->isValueDependent() && 5665 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5666 Val = 0; 5667 } else { 5668 EltTy = Val->getType(); 5669 } 5670 } 5671 } 5672 5673 if (!Val) { 5674 if (LastEnumConst) { 5675 // Assign the last value + 1. 5676 EnumVal = LastEnumConst->getInitVal(); 5677 ++EnumVal; 5678 5679 // Check for overflow on increment. 5680 if (EnumVal < LastEnumConst->getInitVal()) 5681 Diag(IdLoc, diag::warn_enum_value_overflow); 5682 5683 EltTy = LastEnumConst->getType(); 5684 } else { 5685 // First value, set to zero. 5686 EltTy = Context.IntTy; 5687 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5688 } 5689 } 5690 5691 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5692 5693 val.release(); 5694 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5695 Val, EnumVal); 5696} 5697 5698 5699Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5700 DeclPtrTy lastEnumConst, 5701 SourceLocation IdLoc, 5702 IdentifierInfo *Id, 5703 SourceLocation EqualLoc, ExprTy *val) { 5704 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5705 EnumConstantDecl *LastEnumConst = 5706 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5707 Expr *Val = static_cast<Expr*>(val); 5708 5709 // The scope passed in may not be a decl scope. Zip up the scope tree until 5710 // we find one that is. 5711 S = getNonFieldDeclScope(S); 5712 5713 // Verify that there isn't already something declared with this name in this 5714 // scope. 5715 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5716 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5717 // Maybe we will complain about the shadowed template parameter. 5718 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5719 // Just pretend that we didn't see the previous declaration. 5720 PrevDecl = 0; 5721 } 5722 5723 if (PrevDecl) { 5724 // When in C++, we may get a TagDecl with the same name; in this case the 5725 // enum constant will 'hide' the tag. 5726 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5727 "Received TagDecl when not in C++!"); 5728 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5729 if (isa<EnumConstantDecl>(PrevDecl)) 5730 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5731 else 5732 Diag(IdLoc, diag::err_redefinition) << Id; 5733 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5734 if (Val) Val->Destroy(Context); 5735 return DeclPtrTy(); 5736 } 5737 } 5738 5739 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5740 IdLoc, Id, Owned(Val)); 5741 5742 // Register this decl in the current scope stack. 5743 if (New) 5744 PushOnScopeChains(New, S); 5745 5746 return DeclPtrTy::make(New); 5747} 5748 5749void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5750 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5751 DeclPtrTy *Elements, unsigned NumElements, 5752 Scope *S, AttributeList *Attr) { 5753 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5754 QualType EnumType = Context.getTypeDeclType(Enum); 5755 5756 if (Attr) 5757 ProcessDeclAttributeList(S, Enum, Attr); 5758 5759 // TODO: If the result value doesn't fit in an int, it must be a long or long 5760 // long value. ISO C does not support this, but GCC does as an extension, 5761 // emit a warning. 5762 unsigned IntWidth = Context.Target.getIntWidth(); 5763 unsigned CharWidth = Context.Target.getCharWidth(); 5764 unsigned ShortWidth = Context.Target.getShortWidth(); 5765 5766 // Verify that all the values are okay, compute the size of the values, and 5767 // reverse the list. 5768 unsigned NumNegativeBits = 0; 5769 unsigned NumPositiveBits = 0; 5770 5771 // Keep track of whether all elements have type int. 5772 bool AllElementsInt = true; 5773 5774 for (unsigned i = 0; i != NumElements; ++i) { 5775 EnumConstantDecl *ECD = 5776 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5777 if (!ECD) continue; // Already issued a diagnostic. 5778 5779 // If the enum value doesn't fit in an int, emit an extension warning. 5780 const llvm::APSInt &InitVal = ECD->getInitVal(); 5781 assert(InitVal.getBitWidth() >= IntWidth && 5782 "Should have promoted value to int"); 5783 if (InitVal.getBitWidth() > IntWidth) { 5784 llvm::APSInt V(InitVal); 5785 V.trunc(IntWidth); 5786 V.extend(InitVal.getBitWidth()); 5787 if (V != InitVal) 5788 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5789 << InitVal.toString(10); 5790 } 5791 5792 // Keep track of the size of positive and negative values. 5793 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5794 NumPositiveBits = std::max(NumPositiveBits, 5795 (unsigned)InitVal.getActiveBits()); 5796 else 5797 NumNegativeBits = std::max(NumNegativeBits, 5798 (unsigned)InitVal.getMinSignedBits()); 5799 5800 // Keep track of whether every enum element has type int (very commmon). 5801 if (AllElementsInt) 5802 AllElementsInt = ECD->getType() == Context.IntTy; 5803 } 5804 5805 // Figure out the type that should be used for this enum. 5806 // FIXME: Support -fshort-enums. 5807 QualType BestType; 5808 unsigned BestWidth; 5809 5810 // C++0x N3000 [conv.prom]p3: 5811 // An rvalue of an unscoped enumeration type whose underlying 5812 // type is not fixed can be converted to an rvalue of the first 5813 // of the following types that can represent all the values of 5814 // the enumeration: int, unsigned int, long int, unsigned long 5815 // int, long long int, or unsigned long long int. 5816 // C99 6.4.4.3p2: 5817 // An identifier declared as an enumeration constant has type int. 5818 // The C99 rule is modified by a gcc extension 5819 QualType BestPromotionType; 5820 5821 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5822 5823 if (NumNegativeBits) { 5824 // If there is a negative value, figure out the smallest integer type (of 5825 // int/long/longlong) that fits. 5826 // If it's packed, check also if it fits a char or a short. 5827 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5828 BestType = Context.SignedCharTy; 5829 BestWidth = CharWidth; 5830 } else if (Packed && NumNegativeBits <= ShortWidth && 5831 NumPositiveBits < ShortWidth) { 5832 BestType = Context.ShortTy; 5833 BestWidth = ShortWidth; 5834 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5835 BestType = Context.IntTy; 5836 BestWidth = IntWidth; 5837 } else { 5838 BestWidth = Context.Target.getLongWidth(); 5839 5840 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5841 BestType = Context.LongTy; 5842 } else { 5843 BestWidth = Context.Target.getLongLongWidth(); 5844 5845 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5846 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5847 BestType = Context.LongLongTy; 5848 } 5849 } 5850 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5851 } else { 5852 // If there is no negative value, figure out which of uint, ulong, ulonglong 5853 // fits. 5854 // If it's packed, check also if it fits a char or a short. 5855 if (Packed && NumPositiveBits <= CharWidth) { 5856 BestType = Context.UnsignedCharTy; 5857 BestPromotionType = Context.IntTy; 5858 BestWidth = CharWidth; 5859 } else if (Packed && NumPositiveBits <= ShortWidth) { 5860 BestType = Context.UnsignedShortTy; 5861 BestPromotionType = Context.IntTy; 5862 BestWidth = ShortWidth; 5863 } else if (NumPositiveBits <= IntWidth) { 5864 BestType = Context.UnsignedIntTy; 5865 BestWidth = IntWidth; 5866 BestPromotionType = (NumPositiveBits == BestWidth 5867 ? Context.UnsignedIntTy : Context.IntTy); 5868 } else if (NumPositiveBits <= 5869 (BestWidth = Context.Target.getLongWidth())) { 5870 BestType = Context.UnsignedLongTy; 5871 BestPromotionType = (NumPositiveBits == BestWidth 5872 ? Context.UnsignedLongTy : Context.LongTy); 5873 } else { 5874 BestWidth = Context.Target.getLongLongWidth(); 5875 assert(NumPositiveBits <= BestWidth && 5876 "How could an initializer get larger than ULL?"); 5877 BestType = Context.UnsignedLongLongTy; 5878 BestPromotionType = (NumPositiveBits == BestWidth 5879 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5880 } 5881 } 5882 5883 // If we're in C and the promotion type is larger than an int, just 5884 // use the underlying type, which is generally the unsigned integer 5885 // type of the same rank as the promotion type. This is how the gcc 5886 // extension works. 5887 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5888 BestPromotionType = BestType; 5889 5890 // Loop over all of the enumerator constants, changing their types to match 5891 // the type of the enum if needed. 5892 for (unsigned i = 0; i != NumElements; ++i) { 5893 EnumConstantDecl *ECD = 5894 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5895 if (!ECD) continue; // Already issued a diagnostic. 5896 5897 // Standard C says the enumerators have int type, but we allow, as an 5898 // extension, the enumerators to be larger than int size. If each 5899 // enumerator value fits in an int, type it as an int, otherwise type it the 5900 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5901 // that X has type 'int', not 'unsigned'. 5902 if (ECD->getType() == Context.IntTy) { 5903 // Make sure the init value is signed. 5904 llvm::APSInt IV = ECD->getInitVal(); 5905 IV.setIsSigned(true); 5906 ECD->setInitVal(IV); 5907 5908 if (getLangOptions().CPlusPlus) 5909 // C++ [dcl.enum]p4: Following the closing brace of an 5910 // enum-specifier, each enumerator has the type of its 5911 // enumeration. 5912 ECD->setType(EnumType); 5913 continue; // Already int type. 5914 } 5915 5916 // Determine whether the value fits into an int. 5917 llvm::APSInt InitVal = ECD->getInitVal(); 5918 bool FitsInInt; 5919 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5920 FitsInInt = InitVal.getActiveBits() < IntWidth; 5921 else 5922 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5923 5924 // If it fits into an integer type, force it. Otherwise force it to match 5925 // the enum decl type. 5926 QualType NewTy; 5927 unsigned NewWidth; 5928 bool NewSign; 5929 if (FitsInInt) { 5930 NewTy = Context.IntTy; 5931 NewWidth = IntWidth; 5932 NewSign = true; 5933 } else if (ECD->getType() == BestType) { 5934 // Already the right type! 5935 if (getLangOptions().CPlusPlus) 5936 // C++ [dcl.enum]p4: Following the closing brace of an 5937 // enum-specifier, each enumerator has the type of its 5938 // enumeration. 5939 ECD->setType(EnumType); 5940 continue; 5941 } else { 5942 NewTy = BestType; 5943 NewWidth = BestWidth; 5944 NewSign = BestType->isSignedIntegerType(); 5945 } 5946 5947 // Adjust the APSInt value. 5948 InitVal.extOrTrunc(NewWidth); 5949 InitVal.setIsSigned(NewSign); 5950 ECD->setInitVal(InitVal); 5951 5952 // Adjust the Expr initializer and type. 5953 if (ECD->getInitExpr()) 5954 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5955 CastExpr::CK_IntegralCast, 5956 ECD->getInitExpr(), 5957 /*isLvalue=*/false)); 5958 if (getLangOptions().CPlusPlus) 5959 // C++ [dcl.enum]p4: Following the closing brace of an 5960 // enum-specifier, each enumerator has the type of its 5961 // enumeration. 5962 ECD->setType(EnumType); 5963 else 5964 ECD->setType(NewTy); 5965 } 5966 5967 Enum->completeDefinition(Context, BestType, BestPromotionType); 5968} 5969 5970Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5971 ExprArg expr) { 5972 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5973 5974 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5975 Loc, AsmString); 5976 CurContext->addDecl(New); 5977 return DeclPtrTy::make(New); 5978} 5979 5980void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5981 SourceLocation PragmaLoc, 5982 SourceLocation NameLoc) { 5983 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5984 5985 if (PrevDecl) { 5986 PrevDecl->addAttr(::new (Context) WeakAttr()); 5987 } else { 5988 (void)WeakUndeclaredIdentifiers.insert( 5989 std::pair<IdentifierInfo*,WeakInfo> 5990 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5991 } 5992} 5993 5994void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5995 IdentifierInfo* AliasName, 5996 SourceLocation PragmaLoc, 5997 SourceLocation NameLoc, 5998 SourceLocation AliasNameLoc) { 5999 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 6000 WeakInfo W = WeakInfo(Name, NameLoc); 6001 6002 if (PrevDecl) { 6003 if (!PrevDecl->hasAttr<AliasAttr>()) 6004 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6005 DeclApplyPragmaWeak(TUScope, ND, W); 6006 } else { 6007 (void)WeakUndeclaredIdentifiers.insert( 6008 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6009 } 6010} 6011