SemaDecl.cpp revision 1bcee0a5a29981f8c78a8620d1c78841dbc5c348
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 "Lookup.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/Analysis/CFG.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclObjC.h" 22#include "clang/AST/DeclTemplate.h" 23#include "clang/AST/ExprCXX.h" 24#include "clang/AST/StmtCXX.h" 25#include "clang/AST/StmtObjC.h" 26#include "clang/Parse/DeclSpec.h" 27#include "clang/Parse/ParseDiagnostic.h" 28#include "clang/Parse/Template.h" 29#include "clang/Basic/PartialDiagnostic.h" 30#include "clang/Basic/SourceManager.h" 31#include "clang/Basic/TargetInfo.h" 32// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 33#include "clang/Lex/Preprocessor.h" 34#include "clang/Lex/HeaderSearch.h" 35#include "llvm/ADT/BitVector.h" 36#include "llvm/ADT/STLExtras.h" 37#include <algorithm> 38#include <cstring> 39#include <functional> 40#include <queue> 41using namespace clang; 42 43/// getDeclName - Return a pretty name for the specified decl if possible, or 44/// an empty string if not. This is used for pretty crash reporting. 45std::string Sema::getDeclName(DeclPtrTy d) { 46 Decl *D = d.getAs<Decl>(); 47 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 48 return DN->getQualifiedNameAsString(); 49 return ""; 50} 51 52Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 53 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 54} 55 56/// \brief If the identifier refers to a type name within this scope, 57/// return the declaration of that type. 58/// 59/// This routine performs ordinary name lookup of the identifier II 60/// within the given scope, with optional C++ scope specifier SS, to 61/// determine whether the name refers to a type. If so, returns an 62/// opaque pointer (actually a QualType) corresponding to that 63/// type. Otherwise, returns NULL. 64/// 65/// If name lookup results in an ambiguity, this routine will complain 66/// and then return NULL. 67Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 68 Scope *S, const CXXScopeSpec *SS, 69 bool isClassName, 70 TypeTy *ObjectTypePtr) { 71 // Determine where we will perform name lookup. 72 DeclContext *LookupCtx = 0; 73 if (ObjectTypePtr) { 74 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 75 if (ObjectType->isRecordType()) 76 LookupCtx = computeDeclContext(ObjectType); 77 } else if (SS && SS->isSet()) { 78 LookupCtx = computeDeclContext(*SS, false); 79 80 if (!LookupCtx) { 81 if (isDependentScopeSpecifier(*SS)) { 82 // C++ [temp.res]p3: 83 // A qualified-id that refers to a type and in which the 84 // nested-name-specifier depends on a template-parameter (14.6.2) 85 // shall be prefixed by the keyword typename to indicate that the 86 // qualified-id denotes a type, forming an 87 // elaborated-type-specifier (7.1.5.3). 88 // 89 // We therefore do not perform any name lookup if the result would 90 // refer to a member of an unknown specialization. 91 if (!isClassName) 92 return 0; 93 94 // We know from the grammar that this name refers to a type, so build a 95 // TypenameType node to describe the type. 96 // FIXME: Record somewhere that this TypenameType node has no "typename" 97 // keyword associated with it. 98 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 99 II, SS->getRange()).getAsOpaquePtr(); 100 } 101 102 return 0; 103 } 104 105 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 106 return 0; 107 } 108 109 LookupResult Result(*this, &II, NameLoc, LookupOrdinaryName); 110 if (LookupCtx) { 111 // Perform "qualified" name lookup into the declaration context we 112 // computed, which is either the type of the base of a member access 113 // expression or the declaration context associated with a prior 114 // nested-name-specifier. 115 LookupQualifiedName(Result, LookupCtx); 116 117 if (ObjectTypePtr && Result.empty()) { 118 // C++ [basic.lookup.classref]p3: 119 // If the unqualified-id is ~type-name, the type-name is looked up 120 // in the context of the entire postfix-expression. If the type T of 121 // the object expression is of a class type C, the type-name is also 122 // looked up in the scope of class C. At least one of the lookups shall 123 // find a name that refers to (possibly cv-qualified) T. 124 LookupName(Result, S); 125 } 126 } else { 127 // Perform unqualified name lookup. 128 LookupName(Result, S); 129 } 130 131 NamedDecl *IIDecl = 0; 132 switch (Result.getResultKind()) { 133 case LookupResult::NotFound: 134 case LookupResult::FoundOverloaded: 135 case LookupResult::FoundUnresolvedValue: 136 return 0; 137 138 case LookupResult::Ambiguous: 139 // Recover from type-hiding ambiguities by hiding the type. We'll 140 // do the lookup again when looking for an object, and we can 141 // diagnose the error then. If we don't do this, then the error 142 // about hiding the type will be immediately followed by an error 143 // that only makes sense if the identifier was treated like a type. 144 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 145 Result.suppressDiagnostics(); 146 return 0; 147 } 148 149 // Look to see if we have a type anywhere in the list of results. 150 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 151 Res != ResEnd; ++Res) { 152 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 153 if (!IIDecl || 154 (*Res)->getLocation().getRawEncoding() < 155 IIDecl->getLocation().getRawEncoding()) 156 IIDecl = *Res; 157 } 158 } 159 160 if (!IIDecl) { 161 // None of the entities we found is a type, so there is no way 162 // to even assume that the result is a type. In this case, don't 163 // complain about the ambiguity. The parser will either try to 164 // perform this lookup again (e.g., as an object name), which 165 // will produce the ambiguity, or will complain that it expected 166 // a type name. 167 Result.suppressDiagnostics(); 168 return 0; 169 } 170 171 // We found a type within the ambiguous lookup; diagnose the 172 // ambiguity and then return that type. This might be the right 173 // answer, or it might not be, but it suppresses any attempt to 174 // perform the name lookup again. 175 break; 176 177 case LookupResult::Found: 178 IIDecl = Result.getFoundDecl(); 179 break; 180 } 181 182 assert(IIDecl && "Didn't find decl"); 183 184 QualType T; 185 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 186 DiagnoseUseOfDecl(IIDecl, NameLoc); 187 188 // C++ [temp.local]p2: 189 // Within the scope of a class template specialization or 190 // partial specialization, when the injected-class-name is 191 // not followed by a <, it is equivalent to the 192 // injected-class-name followed by the template-argument s 193 // of the class template specialization or partial 194 // specialization enclosed in <>. 195 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 196 if (RD->isInjectedClassName()) 197 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 198 T = Template->getInjectedClassNameType(Context); 199 200 if (T.isNull()) 201 T = Context.getTypeDeclType(TD); 202 203 if (SS) 204 T = getQualifiedNameType(*SS, T); 205 206 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 207 T = Context.getObjCInterfaceType(IDecl); 208 } else if (UnresolvedUsingTypenameDecl *UUDecl = 209 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 210 // FIXME: preserve source structure information. 211 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 212 } else { 213 // If it's not plausibly a type, suppress diagnostics. 214 Result.suppressDiagnostics(); 215 return 0; 216 } 217 218 return T.getAsOpaquePtr(); 219} 220 221/// isTagName() - This method is called *for error recovery purposes only* 222/// to determine if the specified name is a valid tag name ("struct foo"). If 223/// so, this returns the TST for the tag corresponding to it (TST_enum, 224/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 225/// where the user forgot to specify the tag. 226DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 227 // Do a tag name lookup in this scope. 228 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 229 LookupName(R, S, false); 230 R.suppressDiagnostics(); 231 if (R.getResultKind() == LookupResult::Found) 232 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 233 switch (TD->getTagKind()) { 234 case TagDecl::TK_struct: return DeclSpec::TST_struct; 235 case TagDecl::TK_union: return DeclSpec::TST_union; 236 case TagDecl::TK_class: return DeclSpec::TST_class; 237 case TagDecl::TK_enum: return DeclSpec::TST_enum; 238 } 239 } 240 241 return DeclSpec::TST_unspecified; 242} 243 244bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 245 SourceLocation IILoc, 246 Scope *S, 247 const CXXScopeSpec *SS, 248 TypeTy *&SuggestedType) { 249 // We don't have anything to suggest (yet). 250 SuggestedType = 0; 251 252 // FIXME: Should we move the logic that tries to recover from a missing tag 253 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 254 255 if (!SS) 256 Diag(IILoc, diag::err_unknown_typename) << &II; 257 else if (DeclContext *DC = computeDeclContext(*SS, false)) 258 Diag(IILoc, diag::err_typename_nested_not_found) 259 << &II << DC << SS->getRange(); 260 else if (isDependentScopeSpecifier(*SS)) { 261 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 262 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 263 << SourceRange(SS->getRange().getBegin(), IILoc) 264 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 265 "typename "); 266 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 267 } else { 268 assert(SS && SS->isInvalid() && 269 "Invalid scope specifier has already been diagnosed"); 270 } 271 272 return true; 273} 274 275// Determines the context to return to after temporarily entering a 276// context. This depends in an unnecessarily complicated way on the 277// exact ordering of callbacks from the parser. 278DeclContext *Sema::getContainingDC(DeclContext *DC) { 279 280 // Functions defined inline within classes aren't parsed until we've 281 // finished parsing the top-level class, so the top-level class is 282 // the context we'll need to return to. 283 if (isa<FunctionDecl>(DC)) { 284 DC = DC->getLexicalParent(); 285 286 // A function not defined within a class will always return to its 287 // lexical context. 288 if (!isa<CXXRecordDecl>(DC)) 289 return DC; 290 291 // A C++ inline method/friend is parsed *after* the topmost class 292 // it was declared in is fully parsed ("complete"); the topmost 293 // class is the context we need to return to. 294 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 295 DC = RD; 296 297 // Return the declaration context of the topmost class the inline method is 298 // declared in. 299 return DC; 300 } 301 302 if (isa<ObjCMethodDecl>(DC)) 303 return Context.getTranslationUnitDecl(); 304 305 return DC->getLexicalParent(); 306} 307 308void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 309 assert(getContainingDC(DC) == CurContext && 310 "The next DeclContext should be lexically contained in the current one."); 311 CurContext = DC; 312 S->setEntity(DC); 313} 314 315void Sema::PopDeclContext() { 316 assert(CurContext && "DeclContext imbalance!"); 317 318 CurContext = getContainingDC(CurContext); 319} 320 321/// EnterDeclaratorContext - Used when we must lookup names in the context 322/// of a declarator's nested name specifier. 323void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 324 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 325 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 326 CurContext = DC; 327 assert(CurContext && "No context?"); 328 S->setEntity(CurContext); 329} 330 331void Sema::ExitDeclaratorContext(Scope *S) { 332 S->setEntity(PreDeclaratorDC); 333 PreDeclaratorDC = 0; 334 335 // Reset CurContext to the nearest enclosing context. 336 while (!S->getEntity() && S->getParent()) 337 S = S->getParent(); 338 CurContext = static_cast<DeclContext*>(S->getEntity()); 339 assert(CurContext && "No context?"); 340} 341 342/// \brief Determine whether we allow overloading of the function 343/// PrevDecl with another declaration. 344/// 345/// This routine determines whether overloading is possible, not 346/// whether some new function is actually an overload. It will return 347/// true in C++ (where we can always provide overloads) or, as an 348/// extension, in C when the previous function is already an 349/// overloaded function declaration or has the "overloadable" 350/// attribute. 351static bool AllowOverloadingOfFunction(LookupResult &Previous, 352 ASTContext &Context) { 353 if (Context.getLangOptions().CPlusPlus) 354 return true; 355 356 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 357 return true; 358 359 return (Previous.getResultKind() == LookupResult::Found 360 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 361} 362 363/// Add this decl to the scope shadowed decl chains. 364void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 365 // Move up the scope chain until we find the nearest enclosing 366 // non-transparent context. The declaration will be introduced into this 367 // scope. 368 while (S->getEntity() && 369 ((DeclContext *)S->getEntity())->isTransparentContext()) 370 S = S->getParent(); 371 372 // Add scoped declarations into their context, so that they can be 373 // found later. Declarations without a context won't be inserted 374 // into any context. 375 if (AddToContext) 376 CurContext->addDecl(D); 377 378 // Out-of-line function and variable definitions should not be pushed into 379 // scope. 380 if ((isa<FunctionTemplateDecl>(D) && 381 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 382 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 383 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 384 return; 385 386 // If this replaces anything in the current scope, 387 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 388 IEnd = IdResolver.end(); 389 for (; I != IEnd; ++I) { 390 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 391 S->RemoveDecl(DeclPtrTy::make(*I)); 392 IdResolver.RemoveDecl(*I); 393 394 // Should only need to replace one decl. 395 break; 396 } 397 } 398 399 S->AddDecl(DeclPtrTy::make(D)); 400 IdResolver.AddDecl(D); 401} 402 403bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 404 return IdResolver.isDeclInScope(D, Ctx, Context, S); 405} 406 407static bool isOutOfScopePreviousDeclaration(NamedDecl *, 408 DeclContext*, 409 ASTContext&); 410 411/// Filters out lookup results that don't fall within the given scope 412/// as determined by isDeclInScope. 413static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 414 DeclContext *Ctx, Scope *S, 415 bool ConsiderLinkage) { 416 LookupResult::Filter F = R.makeFilter(); 417 while (F.hasNext()) { 418 NamedDecl *D = F.next(); 419 420 if (SemaRef.isDeclInScope(D, Ctx, S)) 421 continue; 422 423 if (ConsiderLinkage && 424 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 425 continue; 426 427 F.erase(); 428 } 429 430 F.done(); 431} 432 433static bool isUsingDecl(NamedDecl *D) { 434 return isa<UsingShadowDecl>(D) || 435 isa<UnresolvedUsingTypenameDecl>(D) || 436 isa<UnresolvedUsingValueDecl>(D); 437} 438 439/// Removes using shadow declarations from the lookup results. 440static void RemoveUsingDecls(LookupResult &R) { 441 LookupResult::Filter F = R.makeFilter(); 442 while (F.hasNext()) 443 if (isUsingDecl(F.next())) 444 F.erase(); 445 446 F.done(); 447} 448 449static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 450 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 451 return false; 452 453 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 454 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 455 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 456 if (!RD->hasTrivialConstructor()) 457 return false; 458 if (!RD->hasTrivialDestructor()) 459 return false; 460 } 461 } 462 } 463 464 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 465 !isa<ImplicitParamDecl>(D) && 466 D->getDeclContext()->isFunctionOrMethod()); 467} 468 469void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 470 if (S->decl_empty()) return; 471 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 472 "Scope shouldn't contain decls!"); 473 474 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 475 I != E; ++I) { 476 Decl *TmpD = (*I).getAs<Decl>(); 477 assert(TmpD && "This decl didn't get pushed??"); 478 479 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 480 NamedDecl *D = cast<NamedDecl>(TmpD); 481 482 if (!D->getDeclName()) continue; 483 484 // Diagnose unused variables in this scope. 485 if (ShouldDiagnoseUnusedDecl(D)) 486 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 487 488 // Remove this name from our lexical scope. 489 IdResolver.RemoveDecl(D); 490 } 491} 492 493/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 494/// return 0 if one not found. 495ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 496 // The third "scope" argument is 0 since we aren't enabling lazy built-in 497 // creation from this context. 498 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 499 500 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 501} 502 503/// getNonFieldDeclScope - Retrieves the innermost scope, starting 504/// from S, where a non-field would be declared. This routine copes 505/// with the difference between C and C++ scoping rules in structs and 506/// unions. For example, the following code is well-formed in C but 507/// ill-formed in C++: 508/// @code 509/// struct S6 { 510/// enum { BAR } e; 511/// }; 512/// 513/// void test_S6() { 514/// struct S6 a; 515/// a.e = BAR; 516/// } 517/// @endcode 518/// For the declaration of BAR, this routine will return a different 519/// scope. The scope S will be the scope of the unnamed enumeration 520/// within S6. In C++, this routine will return the scope associated 521/// with S6, because the enumeration's scope is a transparent 522/// context but structures can contain non-field names. In C, this 523/// routine will return the translation unit scope, since the 524/// enumeration's scope is a transparent context and structures cannot 525/// contain non-field names. 526Scope *Sema::getNonFieldDeclScope(Scope *S) { 527 while (((S->getFlags() & Scope::DeclScope) == 0) || 528 (S->getEntity() && 529 ((DeclContext *)S->getEntity())->isTransparentContext()) || 530 (S->isClassScope() && !getLangOptions().CPlusPlus)) 531 S = S->getParent(); 532 return S; 533} 534 535void Sema::InitBuiltinVaListType() { 536 if (!Context.getBuiltinVaListType().isNull()) 537 return; 538 539 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 540 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 541 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 542 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 543} 544 545/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 546/// file scope. lazily create a decl for it. ForRedeclaration is true 547/// if we're creating this built-in in anticipation of redeclaring the 548/// built-in. 549NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 550 Scope *S, bool ForRedeclaration, 551 SourceLocation Loc) { 552 Builtin::ID BID = (Builtin::ID)bid; 553 554 if (Context.BuiltinInfo.hasVAListUse(BID)) 555 InitBuiltinVaListType(); 556 557 ASTContext::GetBuiltinTypeError Error; 558 QualType R = Context.GetBuiltinType(BID, Error); 559 switch (Error) { 560 case ASTContext::GE_None: 561 // Okay 562 break; 563 564 case ASTContext::GE_Missing_stdio: 565 if (ForRedeclaration) 566 Diag(Loc, diag::err_implicit_decl_requires_stdio) 567 << Context.BuiltinInfo.GetName(BID); 568 return 0; 569 570 case ASTContext::GE_Missing_setjmp: 571 if (ForRedeclaration) 572 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 573 << Context.BuiltinInfo.GetName(BID); 574 return 0; 575 } 576 577 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 578 Diag(Loc, diag::ext_implicit_lib_function_decl) 579 << Context.BuiltinInfo.GetName(BID) 580 << R; 581 if (Context.BuiltinInfo.getHeaderName(BID) && 582 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 583 != Diagnostic::Ignored) 584 Diag(Loc, diag::note_please_include_header) 585 << Context.BuiltinInfo.getHeaderName(BID) 586 << Context.BuiltinInfo.GetName(BID); 587 } 588 589 FunctionDecl *New = FunctionDecl::Create(Context, 590 Context.getTranslationUnitDecl(), 591 Loc, II, R, /*DInfo=*/0, 592 FunctionDecl::Extern, false, 593 /*hasPrototype=*/true); 594 New->setImplicit(); 595 596 // Create Decl objects for each parameter, adding them to the 597 // FunctionDecl. 598 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 599 llvm::SmallVector<ParmVarDecl*, 16> Params; 600 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 601 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 602 FT->getArgType(i), /*DInfo=*/0, 603 VarDecl::None, 0)); 604 New->setParams(Context, Params.data(), Params.size()); 605 } 606 607 AddKnownFunctionAttributes(New); 608 609 // TUScope is the translation-unit scope to insert this function into. 610 // FIXME: This is hideous. We need to teach PushOnScopeChains to 611 // relate Scopes to DeclContexts, and probably eliminate CurContext 612 // entirely, but we're not there yet. 613 DeclContext *SavedContext = CurContext; 614 CurContext = Context.getTranslationUnitDecl(); 615 PushOnScopeChains(New, TUScope); 616 CurContext = SavedContext; 617 return New; 618} 619 620/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 621/// same name and scope as a previous declaration 'Old'. Figure out 622/// how to resolve this situation, merging decls or emitting 623/// diagnostics as appropriate. If there was an error, set New to be invalid. 624/// 625void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 626 // If the new decl is known invalid already, don't bother doing any 627 // merging checks. 628 if (New->isInvalidDecl()) return; 629 630 // Allow multiple definitions for ObjC built-in typedefs. 631 // FIXME: Verify the underlying types are equivalent! 632 if (getLangOptions().ObjC1) { 633 const IdentifierInfo *TypeID = New->getIdentifier(); 634 switch (TypeID->getLength()) { 635 default: break; 636 case 2: 637 if (!TypeID->isStr("id")) 638 break; 639 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 640 // Install the built-in type for 'id', ignoring the current definition. 641 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 642 return; 643 case 5: 644 if (!TypeID->isStr("Class")) 645 break; 646 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 647 // Install the built-in type for 'Class', ignoring the current definition. 648 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 649 return; 650 case 3: 651 if (!TypeID->isStr("SEL")) 652 break; 653 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 654 // Install the built-in type for 'SEL', ignoring the current definition. 655 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 656 return; 657 case 8: 658 if (!TypeID->isStr("Protocol")) 659 break; 660 Context.setObjCProtoType(New->getUnderlyingType()); 661 return; 662 } 663 // Fall through - the typedef name was not a builtin type. 664 } 665 666 // Verify the old decl was also a type. 667 TypeDecl *Old = 0; 668 if (!OldDecls.isSingleResult() || 669 !(Old = dyn_cast<TypeDecl>(OldDecls.getFoundDecl()))) { 670 Diag(New->getLocation(), diag::err_redefinition_different_kind) 671 << New->getDeclName(); 672 673 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 674 if (OldD->getLocation().isValid()) 675 Diag(OldD->getLocation(), diag::note_previous_definition); 676 677 return New->setInvalidDecl(); 678 } 679 680 // If the old declaration is invalid, just give up here. 681 if (Old->isInvalidDecl()) 682 return New->setInvalidDecl(); 683 684 // Determine the "old" type we'll use for checking and diagnostics. 685 QualType OldType; 686 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 687 OldType = OldTypedef->getUnderlyingType(); 688 else 689 OldType = Context.getTypeDeclType(Old); 690 691 // If the typedef types are not identical, reject them in all languages and 692 // with any extensions enabled. 693 694 if (OldType != New->getUnderlyingType() && 695 Context.getCanonicalType(OldType) != 696 Context.getCanonicalType(New->getUnderlyingType())) { 697 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 698 << New->getUnderlyingType() << OldType; 699 if (Old->getLocation().isValid()) 700 Diag(Old->getLocation(), diag::note_previous_definition); 701 return New->setInvalidDecl(); 702 } 703 704 if (getLangOptions().Microsoft) 705 return; 706 707 // C++ [dcl.typedef]p2: 708 // In a given non-class scope, a typedef specifier can be used to 709 // redefine the name of any type declared in that scope to refer 710 // to the type to which it already refers. 711 if (getLangOptions().CPlusPlus) { 712 if (!isa<CXXRecordDecl>(CurContext)) 713 return; 714 Diag(New->getLocation(), diag::err_redefinition) 715 << New->getDeclName(); 716 Diag(Old->getLocation(), diag::note_previous_definition); 717 return New->setInvalidDecl(); 718 } 719 720 // If we have a redefinition of a typedef in C, emit a warning. This warning 721 // is normally mapped to an error, but can be controlled with 722 // -Wtypedef-redefinition. If either the original or the redefinition is 723 // in a system header, don't emit this for compatibility with GCC. 724 if (PP.getDiagnostics().getSuppressSystemWarnings() && 725 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 726 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 727 return; 728 729 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 730 << New->getDeclName(); 731 Diag(Old->getLocation(), diag::note_previous_definition); 732 return; 733} 734 735/// DeclhasAttr - returns true if decl Declaration already has the target 736/// attribute. 737static bool 738DeclHasAttr(const Decl *decl, const Attr *target) { 739 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 740 if (attr->getKind() == target->getKind()) 741 return true; 742 743 return false; 744} 745 746/// MergeAttributes - append attributes from the Old decl to the New one. 747static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 748 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 749 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 750 Attr *NewAttr = attr->clone(C); 751 NewAttr->setInherited(true); 752 New->addAttr(NewAttr); 753 } 754 } 755} 756 757/// Used in MergeFunctionDecl to keep track of function parameters in 758/// C. 759struct GNUCompatibleParamWarning { 760 ParmVarDecl *OldParm; 761 ParmVarDecl *NewParm; 762 QualType PromotedType; 763}; 764 765/// MergeFunctionDecl - We just parsed a function 'New' from 766/// declarator D which has the same name and scope as a previous 767/// declaration 'Old'. Figure out how to resolve this situation, 768/// merging decls or emitting diagnostics as appropriate. 769/// 770/// In C++, New and Old must be declarations that are not 771/// overloaded. Use IsOverload to determine whether New and Old are 772/// overloaded, and to select the Old declaration that New should be 773/// merged with. 774/// 775/// Returns true if there was an error, false otherwise. 776bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 777 // Verify the old decl was also a function. 778 FunctionDecl *Old = 0; 779 if (FunctionTemplateDecl *OldFunctionTemplate 780 = dyn_cast<FunctionTemplateDecl>(OldD)) 781 Old = OldFunctionTemplate->getTemplatedDecl(); 782 else 783 Old = dyn_cast<FunctionDecl>(OldD); 784 if (!Old) { 785 Diag(New->getLocation(), diag::err_redefinition_different_kind) 786 << New->getDeclName(); 787 Diag(OldD->getLocation(), diag::note_previous_definition); 788 return true; 789 } 790 791 // Determine whether the previous declaration was a definition, 792 // implicit declaration, or a declaration. 793 diag::kind PrevDiag; 794 if (Old->isThisDeclarationADefinition()) 795 PrevDiag = diag::note_previous_definition; 796 else if (Old->isImplicit()) 797 PrevDiag = diag::note_previous_implicit_declaration; 798 else 799 PrevDiag = diag::note_previous_declaration; 800 801 QualType OldQType = Context.getCanonicalType(Old->getType()); 802 QualType NewQType = Context.getCanonicalType(New->getType()); 803 804 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 805 New->getStorageClass() == FunctionDecl::Static && 806 Old->getStorageClass() != FunctionDecl::Static) { 807 Diag(New->getLocation(), diag::err_static_non_static) 808 << New; 809 Diag(Old->getLocation(), PrevDiag); 810 return true; 811 } 812 813 if (getLangOptions().CPlusPlus) { 814 // (C++98 13.1p2): 815 // Certain function declarations cannot be overloaded: 816 // -- Function declarations that differ only in the return type 817 // cannot be overloaded. 818 QualType OldReturnType 819 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 820 QualType NewReturnType 821 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 822 if (OldReturnType != NewReturnType) { 823 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 824 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 825 return true; 826 } 827 828 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 829 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 830 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 831 NewMethod->getLexicalDeclContext()->isRecord()) { 832 // -- Member function declarations with the same name and the 833 // same parameter types cannot be overloaded if any of them 834 // is a static member function declaration. 835 if (OldMethod->isStatic() || NewMethod->isStatic()) { 836 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 837 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 838 return true; 839 } 840 841 // C++ [class.mem]p1: 842 // [...] A member shall not be declared twice in the 843 // member-specification, except that a nested class or member 844 // class template can be declared and then later defined. 845 unsigned NewDiag; 846 if (isa<CXXConstructorDecl>(OldMethod)) 847 NewDiag = diag::err_constructor_redeclared; 848 else if (isa<CXXDestructorDecl>(NewMethod)) 849 NewDiag = diag::err_destructor_redeclared; 850 else if (isa<CXXConversionDecl>(NewMethod)) 851 NewDiag = diag::err_conv_function_redeclared; 852 else 853 NewDiag = diag::err_member_redeclared; 854 855 Diag(New->getLocation(), NewDiag); 856 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 857 } 858 859 // (C++98 8.3.5p3): 860 // All declarations for a function shall agree exactly in both the 861 // return type and the parameter-type-list. 862 if (OldQType == NewQType) 863 return MergeCompatibleFunctionDecls(New, Old); 864 865 // Fall through for conflicting redeclarations and redefinitions. 866 } 867 868 // C: Function types need to be compatible, not identical. This handles 869 // duplicate function decls like "void f(int); void f(enum X);" properly. 870 if (!getLangOptions().CPlusPlus && 871 Context.typesAreCompatible(OldQType, NewQType)) { 872 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 873 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 874 const FunctionProtoType *OldProto = 0; 875 if (isa<FunctionNoProtoType>(NewFuncType) && 876 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 877 // The old declaration provided a function prototype, but the 878 // new declaration does not. Merge in the prototype. 879 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 880 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 881 OldProto->arg_type_end()); 882 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 883 ParamTypes.data(), ParamTypes.size(), 884 OldProto->isVariadic(), 885 OldProto->getTypeQuals()); 886 New->setType(NewQType); 887 New->setHasInheritedPrototype(); 888 889 // Synthesize a parameter for each argument type. 890 llvm::SmallVector<ParmVarDecl*, 16> Params; 891 for (FunctionProtoType::arg_type_iterator 892 ParamType = OldProto->arg_type_begin(), 893 ParamEnd = OldProto->arg_type_end(); 894 ParamType != ParamEnd; ++ParamType) { 895 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 896 SourceLocation(), 0, 897 *ParamType, /*DInfo=*/0, 898 VarDecl::None, 0); 899 Param->setImplicit(); 900 Params.push_back(Param); 901 } 902 903 New->setParams(Context, Params.data(), Params.size()); 904 } 905 906 return MergeCompatibleFunctionDecls(New, Old); 907 } 908 909 // GNU C permits a K&R definition to follow a prototype declaration 910 // if the declared types of the parameters in the K&R definition 911 // match the types in the prototype declaration, even when the 912 // promoted types of the parameters from the K&R definition differ 913 // from the types in the prototype. GCC then keeps the types from 914 // the prototype. 915 // 916 // If a variadic prototype is followed by a non-variadic K&R definition, 917 // the K&R definition becomes variadic. This is sort of an edge case, but 918 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 919 // C99 6.9.1p8. 920 if (!getLangOptions().CPlusPlus && 921 Old->hasPrototype() && !New->hasPrototype() && 922 New->getType()->getAs<FunctionProtoType>() && 923 Old->getNumParams() == New->getNumParams()) { 924 llvm::SmallVector<QualType, 16> ArgTypes; 925 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 926 const FunctionProtoType *OldProto 927 = Old->getType()->getAs<FunctionProtoType>(); 928 const FunctionProtoType *NewProto 929 = New->getType()->getAs<FunctionProtoType>(); 930 931 // Determine whether this is the GNU C extension. 932 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 933 NewProto->getResultType()); 934 bool LooseCompatible = !MergedReturn.isNull(); 935 for (unsigned Idx = 0, End = Old->getNumParams(); 936 LooseCompatible && Idx != End; ++Idx) { 937 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 938 ParmVarDecl *NewParm = New->getParamDecl(Idx); 939 if (Context.typesAreCompatible(OldParm->getType(), 940 NewProto->getArgType(Idx))) { 941 ArgTypes.push_back(NewParm->getType()); 942 } else if (Context.typesAreCompatible(OldParm->getType(), 943 NewParm->getType())) { 944 GNUCompatibleParamWarning Warn 945 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 946 Warnings.push_back(Warn); 947 ArgTypes.push_back(NewParm->getType()); 948 } else 949 LooseCompatible = false; 950 } 951 952 if (LooseCompatible) { 953 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 954 Diag(Warnings[Warn].NewParm->getLocation(), 955 diag::ext_param_promoted_not_compatible_with_prototype) 956 << Warnings[Warn].PromotedType 957 << Warnings[Warn].OldParm->getType(); 958 Diag(Warnings[Warn].OldParm->getLocation(), 959 diag::note_previous_declaration); 960 } 961 962 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 963 ArgTypes.size(), 964 OldProto->isVariadic(), 0)); 965 return MergeCompatibleFunctionDecls(New, Old); 966 } 967 968 // Fall through to diagnose conflicting types. 969 } 970 971 // A function that has already been declared has been redeclared or defined 972 // with a different type- show appropriate diagnostic 973 if (unsigned BuiltinID = Old->getBuiltinID()) { 974 // The user has declared a builtin function with an incompatible 975 // signature. 976 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 977 // The function the user is redeclaring is a library-defined 978 // function like 'malloc' or 'printf'. Warn about the 979 // redeclaration, then pretend that we don't know about this 980 // library built-in. 981 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 982 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 983 << Old << Old->getType(); 984 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 985 Old->setInvalidDecl(); 986 return false; 987 } 988 989 PrevDiag = diag::note_previous_builtin_declaration; 990 } 991 992 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 993 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 994 return true; 995} 996 997/// \brief Completes the merge of two function declarations that are 998/// known to be compatible. 999/// 1000/// This routine handles the merging of attributes and other 1001/// properties of function declarations form the old declaration to 1002/// the new declaration, once we know that New is in fact a 1003/// redeclaration of Old. 1004/// 1005/// \returns false 1006bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1007 // Merge the attributes 1008 MergeAttributes(New, Old, Context); 1009 1010 // Merge the storage class. 1011 if (Old->getStorageClass() != FunctionDecl::Extern && 1012 Old->getStorageClass() != FunctionDecl::None) 1013 New->setStorageClass(Old->getStorageClass()); 1014 1015 // Merge "pure" flag. 1016 if (Old->isPure()) 1017 New->setPure(); 1018 1019 // Merge the "deleted" flag. 1020 if (Old->isDeleted()) 1021 New->setDeleted(); 1022 1023 if (getLangOptions().CPlusPlus) 1024 return MergeCXXFunctionDecl(New, Old); 1025 1026 return false; 1027} 1028 1029/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1030/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1031/// situation, merging decls or emitting diagnostics as appropriate. 1032/// 1033/// Tentative definition rules (C99 6.9.2p2) are checked by 1034/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1035/// definitions here, since the initializer hasn't been attached. 1036/// 1037void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1038 // If the new decl is already invalid, don't do any other checking. 1039 if (New->isInvalidDecl()) 1040 return; 1041 1042 // Verify the old decl was also a variable. 1043 VarDecl *Old = 0; 1044 if (!Previous.isSingleResult() || 1045 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1046 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1047 << New->getDeclName(); 1048 Diag(Previous.getRepresentativeDecl()->getLocation(), 1049 diag::note_previous_definition); 1050 return New->setInvalidDecl(); 1051 } 1052 1053 MergeAttributes(New, Old, Context); 1054 1055 // Merge the types 1056 QualType MergedT; 1057 if (getLangOptions().CPlusPlus) { 1058 if (Context.hasSameType(New->getType(), Old->getType())) 1059 MergedT = New->getType(); 1060 // C++ [basic.types]p7: 1061 // [...] The declared type of an array object might be an array of 1062 // unknown size and therefore be incomplete at one point in a 1063 // translation unit and complete later on; [...] 1064 else if (Old->getType()->isIncompleteArrayType() && 1065 New->getType()->isArrayType()) { 1066 CanQual<ArrayType> OldArray 1067 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1068 CanQual<ArrayType> NewArray 1069 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1070 if (OldArray->getElementType() == NewArray->getElementType()) 1071 MergedT = New->getType(); 1072 } 1073 } else { 1074 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1075 } 1076 if (MergedT.isNull()) { 1077 Diag(New->getLocation(), diag::err_redefinition_different_type) 1078 << New->getDeclName(); 1079 Diag(Old->getLocation(), diag::note_previous_definition); 1080 return New->setInvalidDecl(); 1081 } 1082 New->setType(MergedT); 1083 1084 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1085 if (New->getStorageClass() == VarDecl::Static && 1086 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1087 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1088 Diag(Old->getLocation(), diag::note_previous_definition); 1089 return New->setInvalidDecl(); 1090 } 1091 // C99 6.2.2p4: 1092 // For an identifier declared with the storage-class specifier 1093 // extern in a scope in which a prior declaration of that 1094 // identifier is visible,23) if the prior declaration specifies 1095 // internal or external linkage, the linkage of the identifier at 1096 // the later declaration is the same as the linkage specified at 1097 // the prior declaration. If no prior declaration is visible, or 1098 // if the prior declaration specifies no linkage, then the 1099 // identifier has external linkage. 1100 if (New->hasExternalStorage() && Old->hasLinkage()) 1101 /* Okay */; 1102 else if (New->getStorageClass() != VarDecl::Static && 1103 Old->getStorageClass() == VarDecl::Static) { 1104 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1105 Diag(Old->getLocation(), diag::note_previous_definition); 1106 return New->setInvalidDecl(); 1107 } 1108 1109 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1110 1111 // FIXME: The test for external storage here seems wrong? We still 1112 // need to check for mismatches. 1113 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1114 // Don't complain about out-of-line definitions of static members. 1115 !(Old->getLexicalDeclContext()->isRecord() && 1116 !New->getLexicalDeclContext()->isRecord())) { 1117 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1118 Diag(Old->getLocation(), diag::note_previous_definition); 1119 return New->setInvalidDecl(); 1120 } 1121 1122 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1123 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1124 Diag(Old->getLocation(), diag::note_previous_definition); 1125 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1126 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1127 Diag(Old->getLocation(), diag::note_previous_definition); 1128 } 1129 1130 // Keep a chain of previous declarations. 1131 New->setPreviousDeclaration(Old); 1132} 1133 1134/// CheckFallThrough - Check that we don't fall off the end of a 1135/// Statement that should return a value. 1136/// 1137/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1138/// MaybeFallThrough iff we might or might not fall off the end, 1139/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1140/// return. We assume NeverFallThrough iff we never fall off the end of the 1141/// statement but we may return. We assume that functions not marked noreturn 1142/// will return. 1143Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1144 // FIXME: Eventually share this CFG object when we have other warnings based 1145 // of the CFG. This can be done using AnalysisContext. 1146 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1147 1148 // FIXME: They should never return 0, fix that, delete this code. 1149 if (cfg == 0) 1150 // FIXME: This should be NeverFallThrough 1151 return NeverFallThroughOrReturn; 1152 // The CFG leaves in dead things, and we don't want to dead code paths to 1153 // confuse us, so we mark all live things first. 1154 std::queue<CFGBlock*> workq; 1155 llvm::BitVector live(cfg->getNumBlockIDs()); 1156 // Prep work queue 1157 workq.push(&cfg->getEntry()); 1158 // Solve 1159 while (!workq.empty()) { 1160 CFGBlock *item = workq.front(); 1161 workq.pop(); 1162 live.set(item->getBlockID()); 1163 for (CFGBlock::succ_iterator I=item->succ_begin(), 1164 E=item->succ_end(); 1165 I != E; 1166 ++I) { 1167 if ((*I) && !live[(*I)->getBlockID()]) { 1168 live.set((*I)->getBlockID()); 1169 workq.push(*I); 1170 } 1171 } 1172 } 1173 1174 // Now we know what is live, we check the live precessors of the exit block 1175 // and look for fall through paths, being careful to ignore normal returns, 1176 // and exceptional paths. 1177 bool HasLiveReturn = false; 1178 bool HasFakeEdge = false; 1179 bool HasPlainEdge = false; 1180 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1181 E = cfg->getExit().pred_end(); 1182 I != E; 1183 ++I) { 1184 CFGBlock& B = **I; 1185 if (!live[B.getBlockID()]) 1186 continue; 1187 if (B.size() == 0) { 1188 // A labeled empty statement, or the entry block... 1189 HasPlainEdge = true; 1190 continue; 1191 } 1192 Stmt *S = B[B.size()-1]; 1193 if (isa<ReturnStmt>(S)) { 1194 HasLiveReturn = true; 1195 continue; 1196 } 1197 if (isa<ObjCAtThrowStmt>(S)) { 1198 HasFakeEdge = true; 1199 continue; 1200 } 1201 if (isa<CXXThrowExpr>(S)) { 1202 HasFakeEdge = true; 1203 continue; 1204 } 1205 bool NoReturnEdge = false; 1206 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1207 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1208 if (CEE->getType().getNoReturnAttr()) { 1209 NoReturnEdge = true; 1210 HasFakeEdge = true; 1211 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1212 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1213 if (FD->hasAttr<NoReturnAttr>()) { 1214 NoReturnEdge = true; 1215 HasFakeEdge = true; 1216 } 1217 } 1218 } 1219 } 1220 // FIXME: Add noreturn message sends. 1221 if (NoReturnEdge == false) 1222 HasPlainEdge = true; 1223 } 1224 if (!HasPlainEdge) { 1225 if (HasLiveReturn) 1226 return NeverFallThrough; 1227 return NeverFallThroughOrReturn; 1228 } 1229 if (HasFakeEdge || HasLiveReturn) 1230 return MaybeFallThrough; 1231 // This says AlwaysFallThrough for calls to functions that are not marked 1232 // noreturn, that don't return. If people would like this warning to be more 1233 // accurate, such functions should be marked as noreturn. 1234 return AlwaysFallThrough; 1235} 1236 1237/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1238/// function that should return a value. Check that we don't fall off the end 1239/// of a noreturn function. We assume that functions and blocks not marked 1240/// noreturn will return. 1241void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1242 // FIXME: Would be nice if we had a better way to control cascading errors, 1243 // but for now, avoid them. The problem is that when Parse sees: 1244 // int foo() { return a; } 1245 // The return is eaten and the Sema code sees just: 1246 // int foo() { } 1247 // which this code would then warn about. 1248 if (getDiagnostics().hasErrorOccurred()) 1249 return; 1250 1251 bool ReturnsVoid = false; 1252 bool HasNoReturn = false; 1253 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1254 // If the result type of the function is a dependent type, we don't know 1255 // whether it will be void or not, so don't 1256 if (FD->getResultType()->isDependentType()) 1257 return; 1258 if (FD->getResultType()->isVoidType()) 1259 ReturnsVoid = true; 1260 if (FD->hasAttr<NoReturnAttr>()) 1261 HasNoReturn = true; 1262 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1263 if (MD->getResultType()->isVoidType()) 1264 ReturnsVoid = true; 1265 if (MD->hasAttr<NoReturnAttr>()) 1266 HasNoReturn = true; 1267 } 1268 1269 // Short circuit for compilation speed. 1270 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1271 == Diagnostic::Ignored || ReturnsVoid) 1272 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1273 == Diagnostic::Ignored || !HasNoReturn) 1274 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1275 == Diagnostic::Ignored || !ReturnsVoid)) 1276 return; 1277 // FIXME: Function try block 1278 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1279 switch (CheckFallThrough(Body)) { 1280 case MaybeFallThrough: 1281 if (HasNoReturn) 1282 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1283 else if (!ReturnsVoid) 1284 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1285 break; 1286 case AlwaysFallThrough: 1287 if (HasNoReturn) 1288 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1289 else if (!ReturnsVoid) 1290 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1291 break; 1292 case NeverFallThroughOrReturn: 1293 if (ReturnsVoid && !HasNoReturn) 1294 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1295 break; 1296 case NeverFallThrough: 1297 break; 1298 } 1299 } 1300} 1301 1302/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1303/// that should return a value. Check that we don't fall off the end of a 1304/// noreturn block. We assume that functions and blocks not marked noreturn 1305/// will return. 1306void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1307 // FIXME: Would be nice if we had a better way to control cascading errors, 1308 // but for now, avoid them. The problem is that when Parse sees: 1309 // int foo() { return a; } 1310 // The return is eaten and the Sema code sees just: 1311 // int foo() { } 1312 // which this code would then warn about. 1313 if (getDiagnostics().hasErrorOccurred()) 1314 return; 1315 bool ReturnsVoid = false; 1316 bool HasNoReturn = false; 1317 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1318 if (FT->getResultType()->isVoidType()) 1319 ReturnsVoid = true; 1320 if (FT->getNoReturnAttr()) 1321 HasNoReturn = true; 1322 } 1323 1324 // Short circuit for compilation speed. 1325 if (ReturnsVoid 1326 && !HasNoReturn 1327 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1328 == Diagnostic::Ignored || !ReturnsVoid)) 1329 return; 1330 // FIXME: Funtion try block 1331 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1332 switch (CheckFallThrough(Body)) { 1333 case MaybeFallThrough: 1334 if (HasNoReturn) 1335 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1336 else if (!ReturnsVoid) 1337 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1338 break; 1339 case AlwaysFallThrough: 1340 if (HasNoReturn) 1341 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1342 else if (!ReturnsVoid) 1343 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1344 break; 1345 case NeverFallThroughOrReturn: 1346 if (ReturnsVoid) 1347 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1348 break; 1349 case NeverFallThrough: 1350 break; 1351 } 1352 } 1353} 1354 1355/// CheckParmsForFunctionDef - Check that the parameters of the given 1356/// function are appropriate for the definition of a function. This 1357/// takes care of any checks that cannot be performed on the 1358/// declaration itself, e.g., that the types of each of the function 1359/// parameters are complete. 1360bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1361 bool HasInvalidParm = false; 1362 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1363 ParmVarDecl *Param = FD->getParamDecl(p); 1364 1365 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1366 // function declarator that is part of a function definition of 1367 // that function shall not have incomplete type. 1368 // 1369 // This is also C++ [dcl.fct]p6. 1370 if (!Param->isInvalidDecl() && 1371 RequireCompleteType(Param->getLocation(), Param->getType(), 1372 diag::err_typecheck_decl_incomplete_type)) { 1373 Param->setInvalidDecl(); 1374 HasInvalidParm = true; 1375 } 1376 1377 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1378 // declaration of each parameter shall include an identifier. 1379 if (Param->getIdentifier() == 0 && 1380 !Param->isImplicit() && 1381 !getLangOptions().CPlusPlus) 1382 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1383 } 1384 1385 return HasInvalidParm; 1386} 1387 1388/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1389/// no declarator (e.g. "struct foo;") is parsed. 1390Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1391 // FIXME: Error on auto/register at file scope 1392 // FIXME: Error on inline/virtual/explicit 1393 // FIXME: Error on invalid restrict 1394 // FIXME: Warn on useless __thread 1395 // FIXME: Warn on useless const/volatile 1396 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1397 // FIXME: Warn on useless attributes 1398 Decl *TagD = 0; 1399 TagDecl *Tag = 0; 1400 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1401 DS.getTypeSpecType() == DeclSpec::TST_struct || 1402 DS.getTypeSpecType() == DeclSpec::TST_union || 1403 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1404 TagD = static_cast<Decl *>(DS.getTypeRep()); 1405 1406 if (!TagD) // We probably had an error 1407 return DeclPtrTy(); 1408 1409 // Note that the above type specs guarantee that the 1410 // type rep is a Decl, whereas in many of the others 1411 // it's a Type. 1412 Tag = dyn_cast<TagDecl>(TagD); 1413 } 1414 1415 if (DS.isFriendSpecified()) { 1416 // If we're dealing with a class template decl, assume that the 1417 // template routines are handling it. 1418 if (TagD && isa<ClassTemplateDecl>(TagD)) 1419 return DeclPtrTy(); 1420 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1421 } 1422 1423 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1424 // If there are attributes in the DeclSpec, apply them to the record. 1425 if (const AttributeList *AL = DS.getAttributes()) 1426 ProcessDeclAttributeList(S, Record, AL); 1427 1428 if (!Record->getDeclName() && Record->isDefinition() && 1429 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1430 if (getLangOptions().CPlusPlus || 1431 Record->getDeclContext()->isRecord()) 1432 return BuildAnonymousStructOrUnion(S, DS, Record); 1433 1434 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1435 << DS.getSourceRange(); 1436 } 1437 1438 // Microsoft allows unnamed struct/union fields. Don't complain 1439 // about them. 1440 // FIXME: Should we support Microsoft's extensions in this area? 1441 if (Record->getDeclName() && getLangOptions().Microsoft) 1442 return DeclPtrTy::make(Tag); 1443 } 1444 1445 if (!DS.isMissingDeclaratorOk() && 1446 DS.getTypeSpecType() != DeclSpec::TST_error) { 1447 // Warn about typedefs of enums without names, since this is an 1448 // extension in both Microsoft an GNU. 1449 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1450 Tag && isa<EnumDecl>(Tag)) { 1451 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1452 << DS.getSourceRange(); 1453 return DeclPtrTy::make(Tag); 1454 } 1455 1456 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1457 << DS.getSourceRange(); 1458 return DeclPtrTy(); 1459 } 1460 1461 return DeclPtrTy::make(Tag); 1462} 1463 1464/// We are trying to introduce the given name into the given context; 1465/// check if there's an existing declaration that can't be overloaded. 1466/// 1467/// \return true if this is a forbidden redeclaration 1468bool Sema::CheckRedeclaration(DeclContext *DC, 1469 DeclarationName Name, 1470 SourceLocation NameLoc, 1471 unsigned diagnostic) { 1472 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName, 1473 ForRedeclaration); 1474 LookupQualifiedName(R, DC); 1475 1476 if (R.empty()) return false; 1477 1478 if (R.getResultKind() == LookupResult::Found && 1479 isa<TagDecl>(R.getFoundDecl())) 1480 return false; 1481 1482 // Pick a representative declaration. 1483 NamedDecl *PrevDecl = (*R.begin())->getUnderlyingDecl(); 1484 1485 Diag(NameLoc, diagnostic) << Name; 1486 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1487 1488 return true; 1489} 1490 1491/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1492/// anonymous struct or union AnonRecord into the owning context Owner 1493/// and scope S. This routine will be invoked just after we realize 1494/// that an unnamed union or struct is actually an anonymous union or 1495/// struct, e.g., 1496/// 1497/// @code 1498/// union { 1499/// int i; 1500/// float f; 1501/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1502/// // f into the surrounding scope.x 1503/// @endcode 1504/// 1505/// This routine is recursive, injecting the names of nested anonymous 1506/// structs/unions into the owning context and scope as well. 1507bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1508 RecordDecl *AnonRecord) { 1509 unsigned diagKind 1510 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1511 : diag::err_anonymous_struct_member_redecl; 1512 1513 bool Invalid = false; 1514 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1515 FEnd = AnonRecord->field_end(); 1516 F != FEnd; ++F) { 1517 if ((*F)->getDeclName()) { 1518 if (CheckRedeclaration(Owner, (*F)->getDeclName(), 1519 (*F)->getLocation(), diagKind)) { 1520 // C++ [class.union]p2: 1521 // The names of the members of an anonymous union shall be 1522 // distinct from the names of any other entity in the 1523 // scope in which the anonymous union is declared. 1524 Invalid = true; 1525 } else { 1526 // C++ [class.union]p2: 1527 // For the purpose of name lookup, after the anonymous union 1528 // definition, the members of the anonymous union are 1529 // considered to have been defined in the scope in which the 1530 // anonymous union is declared. 1531 Owner->makeDeclVisibleInContext(*F); 1532 S->AddDecl(DeclPtrTy::make(*F)); 1533 IdResolver.AddDecl(*F); 1534 } 1535 } else if (const RecordType *InnerRecordType 1536 = (*F)->getType()->getAs<RecordType>()) { 1537 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1538 if (InnerRecord->isAnonymousStructOrUnion()) 1539 Invalid = Invalid || 1540 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1541 } 1542 } 1543 1544 return Invalid; 1545} 1546 1547/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1548/// anonymous structure or union. Anonymous unions are a C++ feature 1549/// (C++ [class.union]) and a GNU C extension; anonymous structures 1550/// are a GNU C and GNU C++ extension. 1551Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1552 RecordDecl *Record) { 1553 DeclContext *Owner = Record->getDeclContext(); 1554 1555 // Diagnose whether this anonymous struct/union is an extension. 1556 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1557 Diag(Record->getLocation(), diag::ext_anonymous_union); 1558 else if (!Record->isUnion()) 1559 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1560 1561 // C and C++ require different kinds of checks for anonymous 1562 // structs/unions. 1563 bool Invalid = false; 1564 if (getLangOptions().CPlusPlus) { 1565 const char* PrevSpec = 0; 1566 unsigned DiagID; 1567 // C++ [class.union]p3: 1568 // Anonymous unions declared in a named namespace or in the 1569 // global namespace shall be declared static. 1570 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1571 (isa<TranslationUnitDecl>(Owner) || 1572 (isa<NamespaceDecl>(Owner) && 1573 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1574 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1575 Invalid = true; 1576 1577 // Recover by adding 'static'. 1578 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1579 PrevSpec, DiagID); 1580 } 1581 // C++ [class.union]p3: 1582 // A storage class is not allowed in a declaration of an 1583 // anonymous union in a class scope. 1584 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1585 isa<RecordDecl>(Owner)) { 1586 Diag(DS.getStorageClassSpecLoc(), 1587 diag::err_anonymous_union_with_storage_spec); 1588 Invalid = true; 1589 1590 // Recover by removing the storage specifier. 1591 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1592 PrevSpec, DiagID); 1593 } 1594 1595 // C++ [class.union]p2: 1596 // The member-specification of an anonymous union shall only 1597 // define non-static data members. [Note: nested types and 1598 // functions cannot be declared within an anonymous union. ] 1599 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1600 MemEnd = Record->decls_end(); 1601 Mem != MemEnd; ++Mem) { 1602 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1603 // C++ [class.union]p3: 1604 // An anonymous union shall not have private or protected 1605 // members (clause 11). 1606 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1607 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1608 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1609 Invalid = true; 1610 } 1611 } else if ((*Mem)->isImplicit()) { 1612 // Any implicit members are fine. 1613 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1614 // This is a type that showed up in an 1615 // elaborated-type-specifier inside the anonymous struct or 1616 // union, but which actually declares a type outside of the 1617 // anonymous struct or union. It's okay. 1618 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1619 if (!MemRecord->isAnonymousStructOrUnion() && 1620 MemRecord->getDeclName()) { 1621 // This is a nested type declaration. 1622 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1623 << (int)Record->isUnion(); 1624 Invalid = true; 1625 } 1626 } else { 1627 // We have something that isn't a non-static data 1628 // member. Complain about it. 1629 unsigned DK = diag::err_anonymous_record_bad_member; 1630 if (isa<TypeDecl>(*Mem)) 1631 DK = diag::err_anonymous_record_with_type; 1632 else if (isa<FunctionDecl>(*Mem)) 1633 DK = diag::err_anonymous_record_with_function; 1634 else if (isa<VarDecl>(*Mem)) 1635 DK = diag::err_anonymous_record_with_static; 1636 Diag((*Mem)->getLocation(), DK) 1637 << (int)Record->isUnion(); 1638 Invalid = true; 1639 } 1640 } 1641 } 1642 1643 if (!Record->isUnion() && !Owner->isRecord()) { 1644 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1645 << (int)getLangOptions().CPlusPlus; 1646 Invalid = true; 1647 } 1648 1649 // Mock up a declarator. 1650 Declarator Dc(DS, Declarator::TypeNameContext); 1651 DeclaratorInfo *DInfo = 0; 1652 GetTypeForDeclarator(Dc, S, &DInfo); 1653 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1654 1655 // Create a declaration for this anonymous struct/union. 1656 NamedDecl *Anon = 0; 1657 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1658 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1659 /*IdentifierInfo=*/0, 1660 Context.getTypeDeclType(Record), 1661 DInfo, 1662 /*BitWidth=*/0, /*Mutable=*/false); 1663 Anon->setAccess(AS_public); 1664 if (getLangOptions().CPlusPlus) 1665 FieldCollector->Add(cast<FieldDecl>(Anon)); 1666 } else { 1667 VarDecl::StorageClass SC; 1668 switch (DS.getStorageClassSpec()) { 1669 default: assert(0 && "Unknown storage class!"); 1670 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1671 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1672 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1673 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1674 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1675 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1676 case DeclSpec::SCS_mutable: 1677 // mutable can only appear on non-static class members, so it's always 1678 // an error here 1679 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1680 Invalid = true; 1681 SC = VarDecl::None; 1682 break; 1683 } 1684 1685 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1686 /*IdentifierInfo=*/0, 1687 Context.getTypeDeclType(Record), 1688 DInfo, 1689 SC); 1690 } 1691 Anon->setImplicit(); 1692 1693 // Add the anonymous struct/union object to the current 1694 // context. We'll be referencing this object when we refer to one of 1695 // its members. 1696 Owner->addDecl(Anon); 1697 1698 // Inject the members of the anonymous struct/union into the owning 1699 // context and into the identifier resolver chain for name lookup 1700 // purposes. 1701 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1702 Invalid = true; 1703 1704 // Mark this as an anonymous struct/union type. Note that we do not 1705 // do this until after we have already checked and injected the 1706 // members of this anonymous struct/union type, because otherwise 1707 // the members could be injected twice: once by DeclContext when it 1708 // builds its lookup table, and once by 1709 // InjectAnonymousStructOrUnionMembers. 1710 Record->setAnonymousStructOrUnion(true); 1711 1712 if (Invalid) 1713 Anon->setInvalidDecl(); 1714 1715 return DeclPtrTy::make(Anon); 1716} 1717 1718 1719/// GetNameForDeclarator - Determine the full declaration name for the 1720/// given Declarator. 1721DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1722 return GetNameFromUnqualifiedId(D.getName()); 1723} 1724 1725/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1726DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1727 switch (Name.getKind()) { 1728 case UnqualifiedId::IK_Identifier: 1729 return DeclarationName(Name.Identifier); 1730 1731 case UnqualifiedId::IK_OperatorFunctionId: 1732 return Context.DeclarationNames.getCXXOperatorName( 1733 Name.OperatorFunctionId.Operator); 1734 1735 case UnqualifiedId::IK_LiteralOperatorId: 1736 return Context.DeclarationNames.getCXXLiteralOperatorName( 1737 Name.Identifier); 1738 1739 case UnqualifiedId::IK_ConversionFunctionId: { 1740 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1741 if (Ty.isNull()) 1742 return DeclarationName(); 1743 1744 return Context.DeclarationNames.getCXXConversionFunctionName( 1745 Context.getCanonicalType(Ty)); 1746 } 1747 1748 case UnqualifiedId::IK_ConstructorName: { 1749 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1750 if (Ty.isNull()) 1751 return DeclarationName(); 1752 1753 return Context.DeclarationNames.getCXXConstructorName( 1754 Context.getCanonicalType(Ty)); 1755 } 1756 1757 case UnqualifiedId::IK_DestructorName: { 1758 QualType Ty = GetTypeFromParser(Name.DestructorName); 1759 if (Ty.isNull()) 1760 return DeclarationName(); 1761 1762 return Context.DeclarationNames.getCXXDestructorName( 1763 Context.getCanonicalType(Ty)); 1764 } 1765 1766 case UnqualifiedId::IK_TemplateId: { 1767 TemplateName TName 1768 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1769 return Context.getNameForTemplate(TName); 1770 } 1771 } 1772 1773 assert(false && "Unknown name kind"); 1774 return DeclarationName(); 1775} 1776 1777/// isNearlyMatchingFunction - Determine whether the C++ functions 1778/// Declaration and Definition are "nearly" matching. This heuristic 1779/// is used to improve diagnostics in the case where an out-of-line 1780/// function definition doesn't match any declaration within 1781/// the class or namespace. 1782static bool isNearlyMatchingFunction(ASTContext &Context, 1783 FunctionDecl *Declaration, 1784 FunctionDecl *Definition) { 1785 if (Declaration->param_size() != Definition->param_size()) 1786 return false; 1787 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1788 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1789 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1790 1791 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1792 DefParamTy.getNonReferenceType())) 1793 return false; 1794 } 1795 1796 return true; 1797} 1798 1799Sema::DeclPtrTy 1800Sema::HandleDeclarator(Scope *S, Declarator &D, 1801 MultiTemplateParamsArg TemplateParamLists, 1802 bool IsFunctionDefinition) { 1803 DeclarationName Name = GetNameForDeclarator(D); 1804 1805 // All of these full declarators require an identifier. If it doesn't have 1806 // one, the ParsedFreeStandingDeclSpec action should be used. 1807 if (!Name) { 1808 if (!D.isInvalidType()) // Reject this if we think it is valid. 1809 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1810 diag::err_declarator_need_ident) 1811 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1812 return DeclPtrTy(); 1813 } 1814 1815 // The scope passed in may not be a decl scope. Zip up the scope tree until 1816 // we find one that is. 1817 while ((S->getFlags() & Scope::DeclScope) == 0 || 1818 (S->getFlags() & Scope::TemplateParamScope) != 0) 1819 S = S->getParent(); 1820 1821 // If this is an out-of-line definition of a member of a class template 1822 // or class template partial specialization, we may need to rebuild the 1823 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1824 // for more information. 1825 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1826 // handle expressions properly. 1827 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1828 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1829 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1830 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1831 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1832 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1833 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1834 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1835 // FIXME: Preserve type source info. 1836 QualType T = GetTypeFromParser(DS.getTypeRep()); 1837 EnterDeclaratorContext(S, DC); 1838 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1839 ExitDeclaratorContext(S); 1840 if (T.isNull()) 1841 return DeclPtrTy(); 1842 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1843 } 1844 } 1845 1846 DeclContext *DC; 1847 NamedDecl *New; 1848 1849 DeclaratorInfo *DInfo = 0; 1850 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1851 1852 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1853 ForRedeclaration); 1854 1855 // See if this is a redefinition of a variable in the same scope. 1856 if (D.getCXXScopeSpec().isInvalid()) { 1857 DC = CurContext; 1858 D.setInvalidType(); 1859 } else if (!D.getCXXScopeSpec().isSet()) { 1860 bool IsLinkageLookup = false; 1861 1862 // If the declaration we're planning to build will be a function 1863 // or object with linkage, then look for another declaration with 1864 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1865 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1866 /* Do nothing*/; 1867 else if (R->isFunctionType()) { 1868 if (CurContext->isFunctionOrMethod() || 1869 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1870 IsLinkageLookup = true; 1871 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1872 IsLinkageLookup = true; 1873 else if (CurContext->getLookupContext()->isTranslationUnit() && 1874 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1875 IsLinkageLookup = true; 1876 1877 if (IsLinkageLookup) 1878 Previous.clear(LookupRedeclarationWithLinkage); 1879 1880 DC = CurContext; 1881 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1882 } else { // Something like "int foo::x;" 1883 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1884 1885 if (!DC) { 1886 // If we could not compute the declaration context, it's because the 1887 // declaration context is dependent but does not refer to a class, 1888 // class template, or class template partial specialization. Complain 1889 // and return early, to avoid the coming semantic disaster. 1890 Diag(D.getIdentifierLoc(), 1891 diag::err_template_qualified_declarator_no_match) 1892 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1893 << D.getCXXScopeSpec().getRange(); 1894 return DeclPtrTy(); 1895 } 1896 1897 if (!DC->isDependentContext() && 1898 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1899 return DeclPtrTy(); 1900 1901 LookupQualifiedName(Previous, DC); 1902 1903 // Don't consider using declarations as previous declarations for 1904 // out-of-line members. 1905 RemoveUsingDecls(Previous); 1906 1907 // C++ 7.3.1.2p2: 1908 // Members (including explicit specializations of templates) of a named 1909 // namespace can also be defined outside that namespace by explicit 1910 // qualification of the name being defined, provided that the entity being 1911 // defined was already declared in the namespace and the definition appears 1912 // after the point of declaration in a namespace that encloses the 1913 // declarations namespace. 1914 // 1915 // Note that we only check the context at this point. We don't yet 1916 // have enough information to make sure that PrevDecl is actually 1917 // the declaration we want to match. For example, given: 1918 // 1919 // class X { 1920 // void f(); 1921 // void f(float); 1922 // }; 1923 // 1924 // void X::f(int) { } // ill-formed 1925 // 1926 // In this case, PrevDecl will point to the overload set 1927 // containing the two f's declared in X, but neither of them 1928 // matches. 1929 1930 // First check whether we named the global scope. 1931 if (isa<TranslationUnitDecl>(DC)) { 1932 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1933 << Name << D.getCXXScopeSpec().getRange(); 1934 } else { 1935 DeclContext *Cur = CurContext; 1936 while (isa<LinkageSpecDecl>(Cur)) 1937 Cur = Cur->getParent(); 1938 if (!Cur->Encloses(DC)) { 1939 // The qualifying scope doesn't enclose the original declaration. 1940 // Emit diagnostic based on current scope. 1941 SourceLocation L = D.getIdentifierLoc(); 1942 SourceRange R = D.getCXXScopeSpec().getRange(); 1943 if (isa<FunctionDecl>(Cur)) 1944 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1945 else 1946 Diag(L, diag::err_invalid_declarator_scope) 1947 << Name << cast<NamedDecl>(DC) << R; 1948 D.setInvalidType(); 1949 } 1950 } 1951 } 1952 1953 if (Previous.isSingleResult() && 1954 Previous.getFoundDecl()->isTemplateParameter()) { 1955 // Maybe we will complain about the shadowed template parameter. 1956 if (!D.isInvalidType()) 1957 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 1958 Previous.getFoundDecl())) 1959 D.setInvalidType(); 1960 1961 // Just pretend that we didn't see the previous declaration. 1962 Previous.clear(); 1963 } 1964 1965 // In C++, the previous declaration we find might be a tag type 1966 // (class or enum). In this case, the new declaration will hide the 1967 // tag type. Note that this does does not apply if we're declaring a 1968 // typedef (C++ [dcl.typedef]p4). 1969 if (Previous.isSingleTagDecl() && 1970 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1971 Previous.clear(); 1972 1973 bool Redeclaration = false; 1974 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1975 if (TemplateParamLists.size()) { 1976 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1977 return DeclPtrTy(); 1978 } 1979 1980 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, Previous, Redeclaration); 1981 } else if (R->isFunctionType()) { 1982 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, Previous, 1983 move(TemplateParamLists), 1984 IsFunctionDefinition, Redeclaration); 1985 } else { 1986 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, Previous, 1987 move(TemplateParamLists), 1988 Redeclaration); 1989 } 1990 1991 if (New == 0) 1992 return DeclPtrTy(); 1993 1994 // If this has an identifier and is not an invalid redeclaration or 1995 // function template specialization, add it to the scope stack. 1996 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1997 !(isa<FunctionDecl>(New) && 1998 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1999 PushOnScopeChains(New, S); 2000 2001 return DeclPtrTy::make(New); 2002} 2003 2004/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2005/// types into constant array types in certain situations which would otherwise 2006/// be errors (for GCC compatibility). 2007static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2008 ASTContext &Context, 2009 bool &SizeIsNegative) { 2010 // This method tries to turn a variable array into a constant 2011 // array even when the size isn't an ICE. This is necessary 2012 // for compatibility with code that depends on gcc's buggy 2013 // constant expression folding, like struct {char x[(int)(char*)2];} 2014 SizeIsNegative = false; 2015 2016 QualifierCollector Qs; 2017 const Type *Ty = Qs.strip(T); 2018 2019 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2020 QualType Pointee = PTy->getPointeeType(); 2021 QualType FixedType = 2022 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2023 if (FixedType.isNull()) return FixedType; 2024 FixedType = Context.getPointerType(FixedType); 2025 return Qs.apply(FixedType); 2026 } 2027 2028 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2029 if (!VLATy) 2030 return QualType(); 2031 // FIXME: We should probably handle this case 2032 if (VLATy->getElementType()->isVariablyModifiedType()) 2033 return QualType(); 2034 2035 Expr::EvalResult EvalResult; 2036 if (!VLATy->getSizeExpr() || 2037 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2038 !EvalResult.Val.isInt()) 2039 return QualType(); 2040 2041 llvm::APSInt &Res = EvalResult.Val.getInt(); 2042 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2043 // TODO: preserve the size expression in declarator info 2044 return Context.getConstantArrayType(VLATy->getElementType(), 2045 Res, ArrayType::Normal, 0); 2046 } 2047 2048 SizeIsNegative = true; 2049 return QualType(); 2050} 2051 2052/// \brief Register the given locally-scoped external C declaration so 2053/// that it can be found later for redeclarations 2054void 2055Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2056 const LookupResult &Previous, 2057 Scope *S) { 2058 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2059 "Decl is not a locally-scoped decl!"); 2060 // Note that we have a locally-scoped external with this name. 2061 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2062 2063 if (!Previous.isSingleResult()) 2064 return; 2065 2066 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2067 2068 // If there was a previous declaration of this variable, it may be 2069 // in our identifier chain. Update the identifier chain with the new 2070 // declaration. 2071 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2072 // The previous declaration was found on the identifer resolver 2073 // chain, so remove it from its scope. 2074 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2075 S = S->getParent(); 2076 2077 if (S) 2078 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2079 } 2080} 2081 2082/// \brief Diagnose function specifiers on a declaration of an identifier that 2083/// does not identify a function. 2084void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2085 // FIXME: We should probably indicate the identifier in question to avoid 2086 // confusion for constructs like "inline int a(), b;" 2087 if (D.getDeclSpec().isInlineSpecified()) 2088 Diag(D.getDeclSpec().getInlineSpecLoc(), 2089 diag::err_inline_non_function); 2090 2091 if (D.getDeclSpec().isVirtualSpecified()) 2092 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2093 diag::err_virtual_non_function); 2094 2095 if (D.getDeclSpec().isExplicitSpecified()) 2096 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2097 diag::err_explicit_non_function); 2098} 2099 2100NamedDecl* 2101Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2102 QualType R, DeclaratorInfo *DInfo, 2103 LookupResult &Previous, bool &Redeclaration) { 2104 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2105 if (D.getCXXScopeSpec().isSet()) { 2106 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2107 << D.getCXXScopeSpec().getRange(); 2108 D.setInvalidType(); 2109 // Pretend we didn't see the scope specifier. 2110 DC = 0; 2111 } 2112 2113 if (getLangOptions().CPlusPlus) { 2114 // Check that there are no default arguments (C++ only). 2115 CheckExtraCXXDefaultArguments(D); 2116 } 2117 2118 DiagnoseFunctionSpecifiers(D); 2119 2120 if (D.getDeclSpec().isThreadSpecified()) 2121 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2122 2123 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2124 if (!NewTD) return 0; 2125 2126 // Handle attributes prior to checking for duplicates in MergeVarDecl 2127 ProcessDeclAttributes(S, NewTD, D); 2128 2129 // Merge the decl with the existing one if appropriate. If the decl is 2130 // in an outer scope, it isn't the same thing. 2131 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2132 if (!Previous.empty()) { 2133 Redeclaration = true; 2134 MergeTypeDefDecl(NewTD, Previous); 2135 } 2136 2137 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2138 // then it shall have block scope. 2139 QualType T = NewTD->getUnderlyingType(); 2140 if (T->isVariablyModifiedType()) { 2141 CurFunctionNeedsScopeChecking = true; 2142 2143 if (S->getFnParent() == 0) { 2144 bool SizeIsNegative; 2145 QualType FixedTy = 2146 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2147 if (!FixedTy.isNull()) { 2148 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2149 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2150 } else { 2151 if (SizeIsNegative) 2152 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2153 else if (T->isVariableArrayType()) 2154 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2155 else 2156 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2157 NewTD->setInvalidDecl(); 2158 } 2159 } 2160 } 2161 2162 // If this is the C FILE type, notify the AST context. 2163 if (IdentifierInfo *II = NewTD->getIdentifier()) 2164 if (!NewTD->isInvalidDecl() && 2165 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2166 if (II->isStr("FILE")) 2167 Context.setFILEDecl(NewTD); 2168 else if (II->isStr("jmp_buf")) 2169 Context.setjmp_bufDecl(NewTD); 2170 else if (II->isStr("sigjmp_buf")) 2171 Context.setsigjmp_bufDecl(NewTD); 2172 } 2173 2174 return NewTD; 2175} 2176 2177/// \brief Determines whether the given declaration is an out-of-scope 2178/// previous declaration. 2179/// 2180/// This routine should be invoked when name lookup has found a 2181/// previous declaration (PrevDecl) that is not in the scope where a 2182/// new declaration by the same name is being introduced. If the new 2183/// declaration occurs in a local scope, previous declarations with 2184/// linkage may still be considered previous declarations (C99 2185/// 6.2.2p4-5, C++ [basic.link]p6). 2186/// 2187/// \param PrevDecl the previous declaration found by name 2188/// lookup 2189/// 2190/// \param DC the context in which the new declaration is being 2191/// declared. 2192/// 2193/// \returns true if PrevDecl is an out-of-scope previous declaration 2194/// for a new delcaration with the same name. 2195static bool 2196isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2197 ASTContext &Context) { 2198 if (!PrevDecl) 2199 return 0; 2200 2201 if (!PrevDecl->hasLinkage()) 2202 return false; 2203 2204 if (Context.getLangOptions().CPlusPlus) { 2205 // C++ [basic.link]p6: 2206 // If there is a visible declaration of an entity with linkage 2207 // having the same name and type, ignoring entities declared 2208 // outside the innermost enclosing namespace scope, the block 2209 // scope declaration declares that same entity and receives the 2210 // linkage of the previous declaration. 2211 DeclContext *OuterContext = DC->getLookupContext(); 2212 if (!OuterContext->isFunctionOrMethod()) 2213 // This rule only applies to block-scope declarations. 2214 return false; 2215 else { 2216 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2217 if (PrevOuterContext->isRecord()) 2218 // We found a member function: ignore it. 2219 return false; 2220 else { 2221 // Find the innermost enclosing namespace for the new and 2222 // previous declarations. 2223 while (!OuterContext->isFileContext()) 2224 OuterContext = OuterContext->getParent(); 2225 while (!PrevOuterContext->isFileContext()) 2226 PrevOuterContext = PrevOuterContext->getParent(); 2227 2228 // The previous declaration is in a different namespace, so it 2229 // isn't the same function. 2230 if (OuterContext->getPrimaryContext() != 2231 PrevOuterContext->getPrimaryContext()) 2232 return false; 2233 } 2234 } 2235 } 2236 2237 return true; 2238} 2239 2240NamedDecl* 2241Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2242 QualType R, DeclaratorInfo *DInfo, 2243 LookupResult &Previous, 2244 MultiTemplateParamsArg TemplateParamLists, 2245 bool &Redeclaration) { 2246 DeclarationName Name = GetNameForDeclarator(D); 2247 2248 // Check that there are no default arguments (C++ only). 2249 if (getLangOptions().CPlusPlus) 2250 CheckExtraCXXDefaultArguments(D); 2251 2252 VarDecl *NewVD; 2253 VarDecl::StorageClass SC; 2254 switch (D.getDeclSpec().getStorageClassSpec()) { 2255 default: assert(0 && "Unknown storage class!"); 2256 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2257 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2258 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2259 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2260 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2261 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2262 case DeclSpec::SCS_mutable: 2263 // mutable can only appear on non-static class members, so it's always 2264 // an error here 2265 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2266 D.setInvalidType(); 2267 SC = VarDecl::None; 2268 break; 2269 } 2270 2271 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2272 if (!II) { 2273 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2274 << Name.getAsString(); 2275 return 0; 2276 } 2277 2278 DiagnoseFunctionSpecifiers(D); 2279 2280 if (!DC->isRecord() && S->getFnParent() == 0) { 2281 // C99 6.9p2: The storage-class specifiers auto and register shall not 2282 // appear in the declaration specifiers in an external declaration. 2283 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2284 2285 // If this is a register variable with an asm label specified, then this 2286 // is a GNU extension. 2287 if (SC == VarDecl::Register && D.getAsmLabel()) 2288 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2289 else 2290 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2291 D.setInvalidType(); 2292 } 2293 } 2294 if (DC->isRecord() && !CurContext->isRecord()) { 2295 // This is an out-of-line definition of a static data member. 2296 if (SC == VarDecl::Static) { 2297 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2298 diag::err_static_out_of_line) 2299 << CodeModificationHint::CreateRemoval( 2300 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2301 } else if (SC == VarDecl::None) 2302 SC = VarDecl::Static; 2303 } 2304 if (SC == VarDecl::Static) { 2305 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2306 if (RD->isLocalClass()) 2307 Diag(D.getIdentifierLoc(), 2308 diag::err_static_data_member_not_allowed_in_local_class) 2309 << Name << RD->getDeclName(); 2310 } 2311 } 2312 2313 // Match up the template parameter lists with the scope specifier, then 2314 // determine whether we have a template or a template specialization. 2315 bool isExplicitSpecialization = false; 2316 if (TemplateParameterList *TemplateParams 2317 = MatchTemplateParametersToScopeSpecifier( 2318 D.getDeclSpec().getSourceRange().getBegin(), 2319 D.getCXXScopeSpec(), 2320 (TemplateParameterList**)TemplateParamLists.get(), 2321 TemplateParamLists.size(), 2322 isExplicitSpecialization)) { 2323 if (TemplateParams->size() > 0) { 2324 // There is no such thing as a variable template. 2325 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2326 << II 2327 << SourceRange(TemplateParams->getTemplateLoc(), 2328 TemplateParams->getRAngleLoc()); 2329 return 0; 2330 } else { 2331 // There is an extraneous 'template<>' for this variable. Complain 2332 // about it, but allow the declaration of the variable. 2333 Diag(TemplateParams->getTemplateLoc(), 2334 diag::err_template_variable_noparams) 2335 << II 2336 << SourceRange(TemplateParams->getTemplateLoc(), 2337 TemplateParams->getRAngleLoc()); 2338 2339 isExplicitSpecialization = true; 2340 } 2341 } 2342 2343 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2344 II, R, DInfo, SC); 2345 2346 if (D.isInvalidType()) 2347 NewVD->setInvalidDecl(); 2348 2349 if (D.getDeclSpec().isThreadSpecified()) { 2350 if (NewVD->hasLocalStorage()) 2351 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2352 else if (!Context.Target.isTLSSupported()) 2353 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2354 else 2355 NewVD->setThreadSpecified(true); 2356 } 2357 2358 // Set the lexical context. If the declarator has a C++ scope specifier, the 2359 // lexical context will be different from the semantic context. 2360 NewVD->setLexicalDeclContext(CurContext); 2361 2362 // Handle attributes prior to checking for duplicates in MergeVarDecl 2363 ProcessDeclAttributes(S, NewVD, D); 2364 2365 // Handle GNU asm-label extension (encoded as an attribute). 2366 if (Expr *E = (Expr*) D.getAsmLabel()) { 2367 // The parser guarantees this is a string. 2368 StringLiteral *SE = cast<StringLiteral>(E); 2369 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2370 } 2371 2372 // Don't consider existing declarations that are in a different 2373 // scope and are out-of-semantic-context declarations (if the new 2374 // declaration has linkage). 2375 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2376 2377 // Merge the decl with the existing one if appropriate. 2378 if (!Previous.empty()) { 2379 if (Previous.isSingleResult() && 2380 isa<FieldDecl>(Previous.getFoundDecl()) && 2381 D.getCXXScopeSpec().isSet()) { 2382 // The user tried to define a non-static data member 2383 // out-of-line (C++ [dcl.meaning]p1). 2384 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2385 << D.getCXXScopeSpec().getRange(); 2386 Previous.clear(); 2387 NewVD->setInvalidDecl(); 2388 } 2389 } else if (D.getCXXScopeSpec().isSet()) { 2390 // No previous declaration in the qualifying scope. 2391 Diag(D.getIdentifierLoc(), diag::err_no_member) 2392 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2393 << D.getCXXScopeSpec().getRange(); 2394 NewVD->setInvalidDecl(); 2395 } 2396 2397 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2398 2399 // This is an explicit specialization of a static data member. Check it. 2400 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2401 CheckMemberSpecialization(NewVD, Previous)) 2402 NewVD->setInvalidDecl(); 2403 2404 // attributes declared post-definition are currently ignored 2405 if (Previous.isSingleResult()) { 2406 const VarDecl *Def = 0; 2407 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2408 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2409 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2410 Diag(Def->getLocation(), diag::note_previous_definition); 2411 } 2412 } 2413 2414 // If this is a locally-scoped extern C variable, update the map of 2415 // such variables. 2416 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2417 !NewVD->isInvalidDecl()) 2418 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2419 2420 return NewVD; 2421} 2422 2423/// \brief Perform semantic checking on a newly-created variable 2424/// declaration. 2425/// 2426/// This routine performs all of the type-checking required for a 2427/// variable declaration once it has been built. It is used both to 2428/// check variables after they have been parsed and their declarators 2429/// have been translated into a declaration, and to check variables 2430/// that have been instantiated from a template. 2431/// 2432/// Sets NewVD->isInvalidDecl() if an error was encountered. 2433void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2434 LookupResult &Previous, 2435 bool &Redeclaration) { 2436 // If the decl is already known invalid, don't check it. 2437 if (NewVD->isInvalidDecl()) 2438 return; 2439 2440 QualType T = NewVD->getType(); 2441 2442 if (T->isObjCInterfaceType()) { 2443 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2444 return NewVD->setInvalidDecl(); 2445 } 2446 2447 // The variable can not have an abstract class type. 2448 if (RequireNonAbstractType(NewVD->getLocation(), T, 2449 diag::err_abstract_type_in_decl, 2450 AbstractVariableType)) 2451 return NewVD->setInvalidDecl(); 2452 2453 // Emit an error if an address space was applied to decl with local storage. 2454 // This includes arrays of objects with address space qualifiers, but not 2455 // automatic variables that point to other address spaces. 2456 // ISO/IEC TR 18037 S5.1.2 2457 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2458 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2459 return NewVD->setInvalidDecl(); 2460 } 2461 2462 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2463 && !NewVD->hasAttr<BlocksAttr>()) 2464 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2465 2466 bool isVM = T->isVariablyModifiedType(); 2467 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2468 NewVD->hasAttr<BlocksAttr>()) 2469 CurFunctionNeedsScopeChecking = true; 2470 2471 if ((isVM && NewVD->hasLinkage()) || 2472 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2473 bool SizeIsNegative; 2474 QualType FixedTy = 2475 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2476 2477 if (FixedTy.isNull() && T->isVariableArrayType()) { 2478 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2479 // FIXME: This won't give the correct result for 2480 // int a[10][n]; 2481 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2482 2483 if (NewVD->isFileVarDecl()) 2484 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2485 << SizeRange; 2486 else if (NewVD->getStorageClass() == VarDecl::Static) 2487 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2488 << SizeRange; 2489 else 2490 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2491 << SizeRange; 2492 return NewVD->setInvalidDecl(); 2493 } 2494 2495 if (FixedTy.isNull()) { 2496 if (NewVD->isFileVarDecl()) 2497 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2498 else 2499 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2500 return NewVD->setInvalidDecl(); 2501 } 2502 2503 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2504 NewVD->setType(FixedTy); 2505 } 2506 2507 if (Previous.empty() && NewVD->isExternC()) { 2508 // Since we did not find anything by this name and we're declaring 2509 // an extern "C" variable, look for a non-visible extern "C" 2510 // declaration with the same name. 2511 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2512 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2513 if (Pos != LocallyScopedExternalDecls.end()) 2514 Previous.addDecl(Pos->second); 2515 } 2516 2517 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2518 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2519 << T; 2520 return NewVD->setInvalidDecl(); 2521 } 2522 2523 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2524 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2525 return NewVD->setInvalidDecl(); 2526 } 2527 2528 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2529 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2530 return NewVD->setInvalidDecl(); 2531 } 2532 2533 if (!Previous.empty()) { 2534 Redeclaration = true; 2535 MergeVarDecl(NewVD, Previous); 2536 } 2537} 2538 2539/// \brief Data used with FindOverriddenMethod 2540struct FindOverriddenMethodData { 2541 Sema *S; 2542 CXXMethodDecl *Method; 2543}; 2544 2545/// \brief Member lookup function that determines whether a given C++ 2546/// method overrides a method in a base class, to be used with 2547/// CXXRecordDecl::lookupInBases(). 2548static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2549 CXXBasePath &Path, 2550 void *UserData) { 2551 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2552 2553 FindOverriddenMethodData *Data 2554 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2555 2556 DeclarationName Name = Data->Method->getDeclName(); 2557 2558 // FIXME: Do we care about other names here too? 2559 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2560 // We really want to find the base class constructor here. 2561 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2562 CanQualType CT = Data->S->Context.getCanonicalType(T); 2563 2564 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2565 } 2566 2567 for (Path.Decls = BaseRecord->lookup(Name); 2568 Path.Decls.first != Path.Decls.second; 2569 ++Path.Decls.first) { 2570 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2571 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2572 return true; 2573 } 2574 } 2575 2576 return false; 2577} 2578 2579/// AddOverriddenMethods - See if a method overrides any in the base classes, 2580/// and if so, check that it's a valid override and remember it. 2581void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2582 // Look for virtual methods in base classes that this method might override. 2583 CXXBasePaths Paths; 2584 FindOverriddenMethodData Data; 2585 Data.Method = MD; 2586 Data.S = this; 2587 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2588 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2589 E = Paths.found_decls_end(); I != E; ++I) { 2590 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2591 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2592 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2593 !CheckOverridingFunctionAttributes(MD, OldMD)) 2594 MD->addOverriddenMethod(OldMD); 2595 } 2596 } 2597 } 2598} 2599 2600NamedDecl* 2601Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2602 QualType R, DeclaratorInfo *DInfo, 2603 LookupResult &Previous, 2604 MultiTemplateParamsArg TemplateParamLists, 2605 bool IsFunctionDefinition, bool &Redeclaration) { 2606 assert(R.getTypePtr()->isFunctionType()); 2607 2608 DeclarationName Name = GetNameForDeclarator(D); 2609 FunctionDecl::StorageClass SC = FunctionDecl::None; 2610 switch (D.getDeclSpec().getStorageClassSpec()) { 2611 default: assert(0 && "Unknown storage class!"); 2612 case DeclSpec::SCS_auto: 2613 case DeclSpec::SCS_register: 2614 case DeclSpec::SCS_mutable: 2615 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2616 diag::err_typecheck_sclass_func); 2617 D.setInvalidType(); 2618 break; 2619 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2620 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2621 case DeclSpec::SCS_static: { 2622 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2623 // C99 6.7.1p5: 2624 // The declaration of an identifier for a function that has 2625 // block scope shall have no explicit storage-class specifier 2626 // other than extern 2627 // See also (C++ [dcl.stc]p4). 2628 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2629 diag::err_static_block_func); 2630 SC = FunctionDecl::None; 2631 } else 2632 SC = FunctionDecl::Static; 2633 break; 2634 } 2635 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2636 } 2637 2638 if (D.getDeclSpec().isThreadSpecified()) 2639 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2640 2641 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2642 bool isInline = D.getDeclSpec().isInlineSpecified(); 2643 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2644 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2645 2646 // Check that the return type is not an abstract class type. 2647 // For record types, this is done by the AbstractClassUsageDiagnoser once 2648 // the class has been completely parsed. 2649 if (!DC->isRecord() && 2650 RequireNonAbstractType(D.getIdentifierLoc(), 2651 R->getAs<FunctionType>()->getResultType(), 2652 diag::err_abstract_type_in_decl, 2653 AbstractReturnType)) 2654 D.setInvalidType(); 2655 2656 // Do not allow returning a objc interface by-value. 2657 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2658 Diag(D.getIdentifierLoc(), 2659 diag::err_object_cannot_be_passed_returned_by_value) << 0 2660 << R->getAs<FunctionType>()->getResultType(); 2661 D.setInvalidType(); 2662 } 2663 2664 bool isVirtualOkay = false; 2665 FunctionDecl *NewFD; 2666 2667 if (isFriend) { 2668 // C++ [class.friend]p5 2669 // A function can be defined in a friend declaration of a 2670 // class . . . . Such a function is implicitly inline. 2671 isInline |= IsFunctionDefinition; 2672 } 2673 2674 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2675 // This is a C++ constructor declaration. 2676 assert(DC->isRecord() && 2677 "Constructors can only be declared in a member context"); 2678 2679 R = CheckConstructorDeclarator(D, R, SC); 2680 2681 // Create the new declaration 2682 NewFD = CXXConstructorDecl::Create(Context, 2683 cast<CXXRecordDecl>(DC), 2684 D.getIdentifierLoc(), Name, R, DInfo, 2685 isExplicit, isInline, 2686 /*isImplicitlyDeclared=*/false); 2687 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2688 // This is a C++ destructor declaration. 2689 if (DC->isRecord()) { 2690 R = CheckDestructorDeclarator(D, SC); 2691 2692 NewFD = CXXDestructorDecl::Create(Context, 2693 cast<CXXRecordDecl>(DC), 2694 D.getIdentifierLoc(), Name, R, 2695 isInline, 2696 /*isImplicitlyDeclared=*/false); 2697 2698 isVirtualOkay = true; 2699 } else { 2700 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2701 2702 // Create a FunctionDecl to satisfy the function definition parsing 2703 // code path. 2704 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2705 Name, R, DInfo, SC, isInline, 2706 /*hasPrototype=*/true); 2707 D.setInvalidType(); 2708 } 2709 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2710 if (!DC->isRecord()) { 2711 Diag(D.getIdentifierLoc(), 2712 diag::err_conv_function_not_member); 2713 return 0; 2714 } 2715 2716 CheckConversionDeclarator(D, R, SC); 2717 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2718 D.getIdentifierLoc(), Name, R, DInfo, 2719 isInline, isExplicit); 2720 2721 isVirtualOkay = true; 2722 } else if (DC->isRecord()) { 2723 // If the of the function is the same as the name of the record, then this 2724 // must be an invalid constructor that has a return type. 2725 // (The parser checks for a return type and makes the declarator a 2726 // constructor if it has no return type). 2727 // must have an invalid constructor that has a return type 2728 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2729 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2730 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2731 << SourceRange(D.getIdentifierLoc()); 2732 return 0; 2733 } 2734 2735 bool isStatic = SC == FunctionDecl::Static; 2736 2737 // [class.free]p1: 2738 // Any allocation function for a class T is a static member 2739 // (even if not explicitly declared static). 2740 if (Name.getCXXOverloadedOperator() == OO_New || 2741 Name.getCXXOverloadedOperator() == OO_Array_New) 2742 isStatic = true; 2743 2744 // [class.free]p6 Any deallocation function for a class X is a static member 2745 // (even if not explicitly declared static). 2746 if (Name.getCXXOverloadedOperator() == OO_Delete || 2747 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2748 isStatic = true; 2749 2750 // This is a C++ method declaration. 2751 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2752 D.getIdentifierLoc(), Name, R, DInfo, 2753 isStatic, isInline); 2754 2755 isVirtualOkay = !isStatic; 2756 } else { 2757 // Determine whether the function was written with a 2758 // prototype. This true when: 2759 // - we're in C++ (where every function has a prototype), 2760 // - there is a prototype in the declarator, or 2761 // - the type R of the function is some kind of typedef or other reference 2762 // to a type name (which eventually refers to a function type). 2763 bool HasPrototype = 2764 getLangOptions().CPlusPlus || 2765 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2766 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2767 2768 NewFD = FunctionDecl::Create(Context, DC, 2769 D.getIdentifierLoc(), 2770 Name, R, DInfo, SC, isInline, HasPrototype); 2771 } 2772 2773 if (D.isInvalidType()) 2774 NewFD->setInvalidDecl(); 2775 2776 // Set the lexical context. If the declarator has a C++ 2777 // scope specifier, or is the object of a friend declaration, the 2778 // lexical context will be different from the semantic context. 2779 NewFD->setLexicalDeclContext(CurContext); 2780 2781 // Match up the template parameter lists with the scope specifier, then 2782 // determine whether we have a template or a template specialization. 2783 FunctionTemplateDecl *FunctionTemplate = 0; 2784 bool isExplicitSpecialization = false; 2785 bool isFunctionTemplateSpecialization = false; 2786 if (TemplateParameterList *TemplateParams 2787 = MatchTemplateParametersToScopeSpecifier( 2788 D.getDeclSpec().getSourceRange().getBegin(), 2789 D.getCXXScopeSpec(), 2790 (TemplateParameterList**)TemplateParamLists.get(), 2791 TemplateParamLists.size(), 2792 isExplicitSpecialization)) { 2793 if (TemplateParams->size() > 0) { 2794 // This is a function template 2795 2796 // Check that we can declare a template here. 2797 if (CheckTemplateDeclScope(S, TemplateParams)) 2798 return 0; 2799 2800 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2801 NewFD->getLocation(), 2802 Name, TemplateParams, 2803 NewFD); 2804 FunctionTemplate->setLexicalDeclContext(CurContext); 2805 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2806 } else { 2807 // This is a function template specialization. 2808 isFunctionTemplateSpecialization = true; 2809 } 2810 2811 // FIXME: Free this memory properly. 2812 TemplateParamLists.release(); 2813 } 2814 2815 // C++ [dcl.fct.spec]p5: 2816 // The virtual specifier shall only be used in declarations of 2817 // nonstatic class member functions that appear within a 2818 // member-specification of a class declaration; see 10.3. 2819 // 2820 if (isVirtual && !NewFD->isInvalidDecl()) { 2821 if (!isVirtualOkay) { 2822 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2823 diag::err_virtual_non_function); 2824 } else if (!CurContext->isRecord()) { 2825 // 'virtual' was specified outside of the class. 2826 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2827 << CodeModificationHint::CreateRemoval( 2828 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2829 } else { 2830 // Okay: Add virtual to the method. 2831 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2832 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2833 CurClass->setAggregate(false); 2834 CurClass->setPOD(false); 2835 CurClass->setEmpty(false); 2836 CurClass->setPolymorphic(true); 2837 CurClass->setHasTrivialConstructor(false); 2838 CurClass->setHasTrivialCopyConstructor(false); 2839 CurClass->setHasTrivialCopyAssignment(false); 2840 } 2841 } 2842 2843 // Filter out previous declarations that don't match the scope. 2844 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2845 2846 if (isFriend) { 2847 // DC is the namespace in which the function is being declared. 2848 assert((DC->isFileContext() || !Previous.empty()) && 2849 "previously-undeclared friend function being created " 2850 "in a non-namespace context"); 2851 2852 if (FunctionTemplate) { 2853 FunctionTemplate->setObjectOfFriendDecl( 2854 /* PreviouslyDeclared= */ !Previous.empty()); 2855 FunctionTemplate->setAccess(AS_public); 2856 } 2857 else 2858 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2859 2860 NewFD->setAccess(AS_public); 2861 } 2862 2863 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2864 !CurContext->isRecord()) { 2865 // C++ [class.static]p1: 2866 // A data or function member of a class may be declared static 2867 // in a class definition, in which case it is a static member of 2868 // the class. 2869 2870 // Complain about the 'static' specifier if it's on an out-of-line 2871 // member function definition. 2872 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2873 diag::err_static_out_of_line) 2874 << CodeModificationHint::CreateRemoval( 2875 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2876 } 2877 2878 // Handle GNU asm-label extension (encoded as an attribute). 2879 if (Expr *E = (Expr*) D.getAsmLabel()) { 2880 // The parser guarantees this is a string. 2881 StringLiteral *SE = cast<StringLiteral>(E); 2882 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2883 } 2884 2885 // Copy the parameter declarations from the declarator D to the function 2886 // declaration NewFD, if they are available. First scavenge them into Params. 2887 llvm::SmallVector<ParmVarDecl*, 16> Params; 2888 if (D.getNumTypeObjects() > 0) { 2889 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2890 2891 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2892 // function that takes no arguments, not a function that takes a 2893 // single void argument. 2894 // We let through "const void" here because Sema::GetTypeForDeclarator 2895 // already checks for that case. 2896 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2897 FTI.ArgInfo[0].Param && 2898 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2899 // Empty arg list, don't push any params. 2900 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2901 2902 // In C++, the empty parameter-type-list must be spelled "void"; a 2903 // typedef of void is not permitted. 2904 if (getLangOptions().CPlusPlus && 2905 Param->getType().getUnqualifiedType() != Context.VoidTy) 2906 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2907 // FIXME: Leaks decl? 2908 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2909 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2910 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2911 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2912 Param->setDeclContext(NewFD); 2913 Params.push_back(Param); 2914 } 2915 } 2916 2917 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2918 // When we're declaring a function with a typedef, typeof, etc as in the 2919 // following example, we'll need to synthesize (unnamed) 2920 // parameters for use in the declaration. 2921 // 2922 // @code 2923 // typedef void fn(int); 2924 // fn f; 2925 // @endcode 2926 2927 // Synthesize a parameter for each argument type. 2928 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2929 AE = FT->arg_type_end(); AI != AE; ++AI) { 2930 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2931 SourceLocation(), 0, 2932 *AI, /*DInfo=*/0, 2933 VarDecl::None, 0); 2934 Param->setImplicit(); 2935 Params.push_back(Param); 2936 } 2937 } else { 2938 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2939 "Should not need args for typedef of non-prototype fn"); 2940 } 2941 // Finally, we know we have the right number of parameters, install them. 2942 NewFD->setParams(Context, Params.data(), Params.size()); 2943 2944 // If the declarator is a template-id, translate the parser's template 2945 // argument list into our AST format. 2946 bool HasExplicitTemplateArgs = false; 2947 TemplateArgumentListInfo TemplateArgs; 2948 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2949 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2950 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 2951 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 2952 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2953 TemplateId->getTemplateArgs(), 2954 TemplateId->NumArgs); 2955 translateTemplateArguments(TemplateArgsPtr, 2956 TemplateArgs); 2957 TemplateArgsPtr.release(); 2958 2959 HasExplicitTemplateArgs = true; 2960 2961 if (FunctionTemplate) { 2962 // FIXME: Diagnose function template with explicit template 2963 // arguments. 2964 HasExplicitTemplateArgs = false; 2965 } else if (!isFunctionTemplateSpecialization && 2966 !D.getDeclSpec().isFriendSpecified()) { 2967 // We have encountered something that the user meant to be a 2968 // specialization (because it has explicitly-specified template 2969 // arguments) but that was not introduced with a "template<>" (or had 2970 // too few of them). 2971 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2972 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2973 << CodeModificationHint::CreateInsertion( 2974 D.getDeclSpec().getSourceRange().getBegin(), 2975 "template<> "); 2976 isFunctionTemplateSpecialization = true; 2977 } 2978 } 2979 2980 if (isFunctionTemplateSpecialization) { 2981 if (CheckFunctionTemplateSpecialization(NewFD, 2982 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 2983 Previous)) 2984 NewFD->setInvalidDecl(); 2985 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2986 CheckMemberSpecialization(NewFD, Previous)) 2987 NewFD->setInvalidDecl(); 2988 2989 // Perform semantic checking on the function declaration. 2990 bool OverloadableAttrRequired = false; // FIXME: HACK! 2991 CheckFunctionDeclaration(NewFD, Previous, isExplicitSpecialization, 2992 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2993 2994 assert((NewFD->isInvalidDecl() || !Redeclaration || 2995 Previous.getResultKind() != LookupResult::FoundOverloaded) && 2996 "previous declaration set still overloaded"); 2997 2998 // If we have a function template, check the template parameter 2999 // list. This will check and merge default template arguments. 3000 if (FunctionTemplate) { 3001 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3002 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3003 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3004 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3005 : TPC_FunctionTemplate); 3006 } 3007 3008 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3009 // An out-of-line member function declaration must also be a 3010 // definition (C++ [dcl.meaning]p1). 3011 // Note that this is not the case for explicit specializations of 3012 // function templates or member functions of class templates, per 3013 // C++ [temp.expl.spec]p2. 3014 if (!IsFunctionDefinition && !isFriend && 3015 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3016 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3017 << D.getCXXScopeSpec().getRange(); 3018 NewFD->setInvalidDecl(); 3019 } else if (!Redeclaration) { 3020 // The user tried to provide an out-of-line definition for a 3021 // function that is a member of a class or namespace, but there 3022 // was no such member function declared (C++ [class.mfct]p2, 3023 // C++ [namespace.memdef]p2). For example: 3024 // 3025 // class X { 3026 // void f() const; 3027 // }; 3028 // 3029 // void X::f() { } // ill-formed 3030 // 3031 // Complain about this problem, and attempt to suggest close 3032 // matches (e.g., those that differ only in cv-qualifiers and 3033 // whether the parameter types are references). 3034 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3035 << Name << DC << D.getCXXScopeSpec().getRange(); 3036 NewFD->setInvalidDecl(); 3037 3038 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3039 ForRedeclaration); 3040 LookupQualifiedName(Prev, DC); 3041 assert(!Prev.isAmbiguous() && 3042 "Cannot have an ambiguity in previous-declaration lookup"); 3043 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3044 Func != FuncEnd; ++Func) { 3045 if (isa<FunctionDecl>(*Func) && 3046 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3047 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3048 } 3049 } 3050 } 3051 3052 // Handle attributes. We need to have merged decls when handling attributes 3053 // (for example to check for conflicts, etc). 3054 // FIXME: This needs to happen before we merge declarations. Then, 3055 // let attribute merging cope with attribute conflicts. 3056 ProcessDeclAttributes(S, NewFD, D); 3057 3058 // attributes declared post-definition are currently ignored 3059 if (Redeclaration && Previous.isSingleResult()) { 3060 const FunctionDecl *Def; 3061 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3062 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3063 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3064 Diag(Def->getLocation(), diag::note_previous_definition); 3065 } 3066 } 3067 3068 AddKnownFunctionAttributes(NewFD); 3069 3070 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3071 // If a function name is overloadable in C, then every function 3072 // with that name must be marked "overloadable". 3073 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3074 << Redeclaration << NewFD; 3075 if (!Previous.empty()) 3076 Diag(Previous.getRepresentativeDecl()->getLocation(), 3077 diag::note_attribute_overloadable_prev_overload); 3078 NewFD->addAttr(::new (Context) OverloadableAttr()); 3079 } 3080 3081 // If this is a locally-scoped extern C function, update the 3082 // map of such names. 3083 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3084 && !NewFD->isInvalidDecl()) 3085 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3086 3087 // Set this FunctionDecl's range up to the right paren. 3088 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3089 3090 if (FunctionTemplate && NewFD->isInvalidDecl()) 3091 FunctionTemplate->setInvalidDecl(); 3092 3093 if (FunctionTemplate) 3094 return FunctionTemplate; 3095 3096 return NewFD; 3097} 3098 3099/// \brief Perform semantic checking of a new function declaration. 3100/// 3101/// Performs semantic analysis of the new function declaration 3102/// NewFD. This routine performs all semantic checking that does not 3103/// require the actual declarator involved in the declaration, and is 3104/// used both for the declaration of functions as they are parsed 3105/// (called via ActOnDeclarator) and for the declaration of functions 3106/// that have been instantiated via C++ template instantiation (called 3107/// via InstantiateDecl). 3108/// 3109/// \param IsExplicitSpecialiation whether this new function declaration is 3110/// an explicit specialization of the previous declaration. 3111/// 3112/// This sets NewFD->isInvalidDecl() to true if there was an error. 3113void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, 3114 LookupResult &Previous, 3115 bool IsExplicitSpecialization, 3116 bool &Redeclaration, 3117 bool &OverloadableAttrRequired) { 3118 // If NewFD is already known erroneous, don't do any of this checking. 3119 if (NewFD->isInvalidDecl()) 3120 return; 3121 3122 if (NewFD->getResultType()->isVariablyModifiedType()) { 3123 // Functions returning a variably modified type violate C99 6.7.5.2p2 3124 // because all functions have linkage. 3125 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3126 return NewFD->setInvalidDecl(); 3127 } 3128 3129 if (NewFD->isMain()) 3130 CheckMain(NewFD); 3131 3132 // Check for a previous declaration of this name. 3133 if (Previous.empty() && NewFD->isExternC()) { 3134 // Since we did not find anything by this name and we're declaring 3135 // an extern "C" function, look for a non-visible extern "C" 3136 // declaration with the same name. 3137 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3138 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3139 if (Pos != LocallyScopedExternalDecls.end()) 3140 Previous.addDecl(Pos->second); 3141 } 3142 3143 // Merge or overload the declaration with an existing declaration of 3144 // the same name, if appropriate. 3145 if (!Previous.empty()) { 3146 // Determine whether NewFD is an overload of PrevDecl or 3147 // a declaration that requires merging. If it's an overload, 3148 // there's no more work to do here; we'll just add the new 3149 // function to the scope. 3150 3151 if (!getLangOptions().CPlusPlus && 3152 AllowOverloadingOfFunction(Previous, Context)) { 3153 OverloadableAttrRequired = true; 3154 3155 // Functions marked "overloadable" must have a prototype (that 3156 // we can't get through declaration merging). 3157 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3158 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3159 << NewFD; 3160 Redeclaration = true; 3161 3162 // Turn this into a variadic function with no parameters. 3163 QualType R = Context.getFunctionType( 3164 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3165 0, 0, true, 0); 3166 NewFD->setType(R); 3167 return NewFD->setInvalidDecl(); 3168 } 3169 } 3170 3171 NamedDecl *OldDecl = 0; 3172 if (!Previous.empty()) { 3173 if (!AllowOverloadingOfFunction(Previous, Context)) { 3174 Redeclaration = true; 3175 OldDecl = Previous.getFoundDecl(); 3176 } else if (!IsOverload(NewFD, Previous, OldDecl)) { 3177 if (!isUsingDecl(OldDecl)) 3178 Redeclaration = true; 3179 } 3180 } 3181 3182 if (Redeclaration) { 3183 // NewFD and OldDecl represent declarations that need to be 3184 // merged. 3185 if (MergeFunctionDecl(NewFD, OldDecl)) 3186 return NewFD->setInvalidDecl(); 3187 3188 Previous.clear(); 3189 Previous.addDecl(OldDecl); 3190 3191 if (FunctionTemplateDecl *OldTemplateDecl 3192 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3193 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3194 FunctionTemplateDecl *NewTemplateDecl 3195 = NewFD->getDescribedFunctionTemplate(); 3196 assert(NewTemplateDecl && "Template/non-template mismatch"); 3197 if (CXXMethodDecl *Method 3198 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3199 Method->setAccess(OldTemplateDecl->getAccess()); 3200 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3201 } 3202 3203 // If this is an explicit specialization of a member that is a function 3204 // template, mark it as a member specialization. 3205 if (IsExplicitSpecialization && 3206 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3207 NewTemplateDecl->setMemberSpecialization(); 3208 assert(OldTemplateDecl->isMemberSpecialization()); 3209 } 3210 } else { 3211 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3212 NewFD->setAccess(OldDecl->getAccess()); 3213 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3214 } 3215 } 3216 } 3217 3218 // Semantic checking for this function declaration (in isolation). 3219 if (getLangOptions().CPlusPlus) { 3220 // C++-specific checks. 3221 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3222 CheckConstructor(Constructor); 3223 } else if (CXXDestructorDecl *Destructor = 3224 dyn_cast<CXXDestructorDecl>(NewFD)) { 3225 CXXRecordDecl *Record = Destructor->getParent(); 3226 QualType ClassType = Context.getTypeDeclType(Record); 3227 3228 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3229 // type is dependent? Both gcc and edg can handle that. 3230 if (!ClassType->isDependentType()) { 3231 DeclarationName Name 3232 = Context.DeclarationNames.getCXXDestructorName( 3233 Context.getCanonicalType(ClassType)); 3234 if (NewFD->getDeclName() != Name) { 3235 Diag(NewFD->getLocation(), diag::err_destructor_name); 3236 return NewFD->setInvalidDecl(); 3237 } 3238 } 3239 3240 Record->setUserDeclaredDestructor(true); 3241 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3242 // user-defined destructor. 3243 Record->setPOD(false); 3244 3245 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3246 // declared destructor. 3247 // FIXME: C++0x: don't do this for "= default" destructors 3248 Record->setHasTrivialDestructor(false); 3249 } else if (CXXConversionDecl *Conversion 3250 = dyn_cast<CXXConversionDecl>(NewFD)) { 3251 ActOnConversionDeclarator(Conversion); 3252 } 3253 3254 // Find any virtual functions that this function overrides. 3255 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3256 if (!Method->isFunctionTemplateSpecialization() && 3257 !Method->getDescribedFunctionTemplate()) 3258 AddOverriddenMethods(Method->getParent(), Method); 3259 } 3260 3261 // Additional checks for the destructor; make sure we do this after we 3262 // figure out whether the destructor is virtual. 3263 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3264 if (!Destructor->getParent()->isDependentType()) 3265 CheckDestructor(Destructor); 3266 3267 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3268 if (NewFD->isOverloadedOperator() && 3269 CheckOverloadedOperatorDeclaration(NewFD)) 3270 return NewFD->setInvalidDecl(); 3271 3272 // In C++, check default arguments now that we have merged decls. Unless 3273 // the lexical context is the class, because in this case this is done 3274 // during delayed parsing anyway. 3275 if (!CurContext->isRecord()) 3276 CheckCXXDefaultArguments(NewFD); 3277 } 3278} 3279 3280void Sema::CheckMain(FunctionDecl* FD) { 3281 // C++ [basic.start.main]p3: A program that declares main to be inline 3282 // or static is ill-formed. 3283 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3284 // shall not appear in a declaration of main. 3285 // static main is not an error under C99, but we should warn about it. 3286 bool isInline = FD->isInlineSpecified(); 3287 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3288 if (isInline || isStatic) { 3289 unsigned diagID = diag::warn_unusual_main_decl; 3290 if (isInline || getLangOptions().CPlusPlus) 3291 diagID = diag::err_unusual_main_decl; 3292 3293 int which = isStatic + (isInline << 1) - 1; 3294 Diag(FD->getLocation(), diagID) << which; 3295 } 3296 3297 QualType T = FD->getType(); 3298 assert(T->isFunctionType() && "function decl is not of function type"); 3299 const FunctionType* FT = T->getAs<FunctionType>(); 3300 3301 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3302 // TODO: add a replacement fixit to turn the return type into 'int'. 3303 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3304 FD->setInvalidDecl(true); 3305 } 3306 3307 // Treat protoless main() as nullary. 3308 if (isa<FunctionNoProtoType>(FT)) return; 3309 3310 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3311 unsigned nparams = FTP->getNumArgs(); 3312 assert(FD->getNumParams() == nparams); 3313 3314 if (nparams > 3) { 3315 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3316 FD->setInvalidDecl(true); 3317 nparams = 3; 3318 } 3319 3320 // FIXME: a lot of the following diagnostics would be improved 3321 // if we had some location information about types. 3322 3323 QualType CharPP = 3324 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3325 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3326 3327 for (unsigned i = 0; i < nparams; ++i) { 3328 QualType AT = FTP->getArgType(i); 3329 3330 bool mismatch = true; 3331 3332 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3333 mismatch = false; 3334 else if (Expected[i] == CharPP) { 3335 // As an extension, the following forms are okay: 3336 // char const ** 3337 // char const * const * 3338 // char * const * 3339 3340 QualifierCollector qs; 3341 const PointerType* PT; 3342 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3343 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3344 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3345 qs.removeConst(); 3346 mismatch = !qs.empty(); 3347 } 3348 } 3349 3350 if (mismatch) { 3351 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3352 // TODO: suggest replacing given type with expected type 3353 FD->setInvalidDecl(true); 3354 } 3355 } 3356 3357 if (nparams == 1 && !FD->isInvalidDecl()) { 3358 Diag(FD->getLocation(), diag::warn_main_one_arg); 3359 } 3360} 3361 3362bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3363 // FIXME: Need strict checking. In C89, we need to check for 3364 // any assignment, increment, decrement, function-calls, or 3365 // commas outside of a sizeof. In C99, it's the same list, 3366 // except that the aforementioned are allowed in unevaluated 3367 // expressions. Everything else falls under the 3368 // "may accept other forms of constant expressions" exception. 3369 // (We never end up here for C++, so the constant expression 3370 // rules there don't matter.) 3371 if (Init->isConstantInitializer(Context)) 3372 return false; 3373 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3374 << Init->getSourceRange(); 3375 return true; 3376} 3377 3378void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3379 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3380} 3381 3382/// AddInitializerToDecl - Adds the initializer Init to the 3383/// declaration dcl. If DirectInit is true, this is C++ direct 3384/// initialization rather than copy initialization. 3385void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3386 Decl *RealDecl = dcl.getAs<Decl>(); 3387 // If there is no declaration, there was an error parsing it. Just ignore 3388 // the initializer. 3389 if (RealDecl == 0) 3390 return; 3391 3392 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3393 // With declarators parsed the way they are, the parser cannot 3394 // distinguish between a normal initializer and a pure-specifier. 3395 // Thus this grotesque test. 3396 IntegerLiteral *IL; 3397 Expr *Init = static_cast<Expr *>(init.get()); 3398 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3399 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3400 CheckPureMethod(Method, Init->getSourceRange()); 3401 else { 3402 Diag(Method->getLocation(), diag::err_member_function_initialization) 3403 << Method->getDeclName() << Init->getSourceRange(); 3404 Method->setInvalidDecl(); 3405 } 3406 return; 3407 } 3408 3409 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3410 if (!VDecl) { 3411 if (getLangOptions().CPlusPlus && 3412 RealDecl->getLexicalDeclContext()->isRecord() && 3413 isa<NamedDecl>(RealDecl)) 3414 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3415 << cast<NamedDecl>(RealDecl)->getDeclName(); 3416 else 3417 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3418 RealDecl->setInvalidDecl(); 3419 return; 3420 } 3421 3422 // A definition must end up with a complete type, which means it must be 3423 // complete with the restriction that an array type might be completed by the 3424 // initializer; note that later code assumes this restriction. 3425 QualType BaseDeclType = VDecl->getType(); 3426 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3427 BaseDeclType = Array->getElementType(); 3428 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3429 diag::err_typecheck_decl_incomplete_type)) { 3430 RealDecl->setInvalidDecl(); 3431 return; 3432 } 3433 3434 const VarDecl *Def = 0; 3435 if (VDecl->getDefinition(Def)) { 3436 Diag(VDecl->getLocation(), diag::err_redefinition) 3437 << VDecl->getDeclName(); 3438 Diag(Def->getLocation(), diag::note_previous_definition); 3439 VDecl->setInvalidDecl(); 3440 return; 3441 } 3442 3443 // Take ownership of the expression, now that we're sure we have somewhere 3444 // to put it. 3445 Expr *Init = init.takeAs<Expr>(); 3446 assert(Init && "missing initializer"); 3447 3448 // Get the decls type and save a reference for later, since 3449 // CheckInitializerTypes may change it. 3450 QualType DclT = VDecl->getType(), SavT = DclT; 3451 if (VDecl->isBlockVarDecl()) { 3452 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3453 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3454 VDecl->setInvalidDecl(); 3455 } else if (!VDecl->isInvalidDecl()) { 3456 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3457 VDecl->getDeclName(), DirectInit)) 3458 VDecl->setInvalidDecl(); 3459 3460 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3461 // Don't check invalid declarations to avoid emitting useless diagnostics. 3462 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3463 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3464 CheckForConstantInitializer(Init, DclT); 3465 } 3466 } 3467 } else if (VDecl->isStaticDataMember() && 3468 VDecl->getLexicalDeclContext()->isRecord()) { 3469 // This is an in-class initialization for a static data member, e.g., 3470 // 3471 // struct S { 3472 // static const int value = 17; 3473 // }; 3474 3475 // Attach the initializer 3476 VDecl->setInit(Context, Init); 3477 3478 // C++ [class.mem]p4: 3479 // A member-declarator can contain a constant-initializer only 3480 // if it declares a static member (9.4) of const integral or 3481 // const enumeration type, see 9.4.2. 3482 QualType T = VDecl->getType(); 3483 if (!T->isDependentType() && 3484 (!Context.getCanonicalType(T).isConstQualified() || 3485 !T->isIntegralType())) { 3486 Diag(VDecl->getLocation(), diag::err_member_initialization) 3487 << VDecl->getDeclName() << Init->getSourceRange(); 3488 VDecl->setInvalidDecl(); 3489 } else { 3490 // C++ [class.static.data]p4: 3491 // If a static data member is of const integral or const 3492 // enumeration type, its declaration in the class definition 3493 // can specify a constant-initializer which shall be an 3494 // integral constant expression (5.19). 3495 if (!Init->isTypeDependent() && 3496 !Init->getType()->isIntegralType()) { 3497 // We have a non-dependent, non-integral or enumeration type. 3498 Diag(Init->getSourceRange().getBegin(), 3499 diag::err_in_class_initializer_non_integral_type) 3500 << Init->getType() << Init->getSourceRange(); 3501 VDecl->setInvalidDecl(); 3502 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3503 // Check whether the expression is a constant expression. 3504 llvm::APSInt Value; 3505 SourceLocation Loc; 3506 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3507 Diag(Loc, diag::err_in_class_initializer_non_constant) 3508 << Init->getSourceRange(); 3509 VDecl->setInvalidDecl(); 3510 } else if (!VDecl->getType()->isDependentType()) 3511 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3512 } 3513 } 3514 } else if (VDecl->isFileVarDecl()) { 3515 if (VDecl->getStorageClass() == VarDecl::Extern) 3516 Diag(VDecl->getLocation(), diag::warn_extern_init); 3517 if (!VDecl->isInvalidDecl()) 3518 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3519 VDecl->getDeclName(), DirectInit)) 3520 VDecl->setInvalidDecl(); 3521 3522 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3523 // Don't check invalid declarations to avoid emitting useless diagnostics. 3524 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3525 // C99 6.7.8p4. All file scoped initializers need to be constant. 3526 CheckForConstantInitializer(Init, DclT); 3527 } 3528 } 3529 // If the type changed, it means we had an incomplete type that was 3530 // completed by the initializer. For example: 3531 // int ary[] = { 1, 3, 5 }; 3532 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3533 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3534 VDecl->setType(DclT); 3535 Init->setType(DclT); 3536 } 3537 3538 Init = MaybeCreateCXXExprWithTemporaries(Init, 3539 /*ShouldDestroyTemporaries=*/true); 3540 // Attach the initializer to the decl. 3541 VDecl->setInit(Context, Init); 3542 3543 // If the previous declaration of VDecl was a tentative definition, 3544 // remove it from the set of tentative definitions. 3545 if (VDecl->getPreviousDeclaration() && 3546 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3547 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3548 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3549 } 3550 3551 return; 3552} 3553 3554void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3555 bool TypeContainsUndeducedAuto) { 3556 Decl *RealDecl = dcl.getAs<Decl>(); 3557 3558 // If there is no declaration, there was an error parsing it. Just ignore it. 3559 if (RealDecl == 0) 3560 return; 3561 3562 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3563 QualType Type = Var->getType(); 3564 3565 // Record tentative definitions. 3566 if (Var->isTentativeDefinition(Context)) { 3567 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3568 InsertPair = 3569 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3570 3571 // Keep the latest definition in the map. If we see 'int i; int i;' we 3572 // want the second one in the map. 3573 InsertPair.first->second = Var; 3574 3575 // However, for the list, we don't care about the order, just make sure 3576 // that there are no dupes for a given declaration name. 3577 if (InsertPair.second) 3578 TentativeDefinitionList.push_back(Var->getDeclName()); 3579 } 3580 3581 // C++ [dcl.init.ref]p3: 3582 // The initializer can be omitted for a reference only in a 3583 // parameter declaration (8.3.5), in the declaration of a 3584 // function return type, in the declaration of a class member 3585 // within its class declaration (9.2), and where the extern 3586 // specifier is explicitly used. 3587 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3588 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3589 << Var->getDeclName() 3590 << SourceRange(Var->getLocation(), Var->getLocation()); 3591 Var->setInvalidDecl(); 3592 return; 3593 } 3594 3595 // C++0x [dcl.spec.auto]p3 3596 if (TypeContainsUndeducedAuto) { 3597 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3598 << Var->getDeclName() << Type; 3599 Var->setInvalidDecl(); 3600 return; 3601 } 3602 3603 // An array without size is an incomplete type, and there are no special 3604 // rules in C++ to make such a definition acceptable. 3605 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3606 !Var->hasExternalStorage()) { 3607 Diag(Var->getLocation(), 3608 diag::err_typecheck_incomplete_array_needs_initializer); 3609 Var->setInvalidDecl(); 3610 return; 3611 } 3612 3613 // C++ [temp.expl.spec]p15: 3614 // An explicit specialization of a static data member of a template is a 3615 // definition if the declaration includes an initializer; otherwise, it 3616 // is a declaration. 3617 if (Var->isStaticDataMember() && 3618 Var->getInstantiatedFromStaticDataMember() && 3619 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3620 return; 3621 3622 // C++ [dcl.init]p9: 3623 // If no initializer is specified for an object, and the object 3624 // is of (possibly cv-qualified) non-POD class type (or array 3625 // thereof), the object shall be default-initialized; if the 3626 // object is of const-qualified type, the underlying class type 3627 // shall have a user-declared default constructor. 3628 // 3629 // FIXME: Diagnose the "user-declared default constructor" bit. 3630 if (getLangOptions().CPlusPlus) { 3631 QualType InitType = Type; 3632 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3633 InitType = Context.getBaseElementType(Array); 3634 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3635 InitType->isRecordType() && !InitType->isDependentType()) { 3636 if (!RequireCompleteType(Var->getLocation(), InitType, 3637 diag::err_invalid_incomplete_type_use)) { 3638 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3639 3640 CXXConstructorDecl *Constructor 3641 = PerformInitializationByConstructor(InitType, 3642 MultiExprArg(*this, 0, 0), 3643 Var->getLocation(), 3644 SourceRange(Var->getLocation(), 3645 Var->getLocation()), 3646 Var->getDeclName(), 3647 IK_Default, 3648 ConstructorArgs); 3649 3650 // FIXME: Location info for the variable initialization? 3651 if (!Constructor) 3652 Var->setInvalidDecl(); 3653 else { 3654 // FIXME: Cope with initialization of arrays 3655 if (!Constructor->isTrivial() && 3656 InitializeVarWithConstructor(Var, Constructor, 3657 move_arg(ConstructorArgs))) 3658 Var->setInvalidDecl(); 3659 3660 FinalizeVarWithDestructor(Var, InitType); 3661 } 3662 } else { 3663 Var->setInvalidDecl(); 3664 } 3665 } 3666 } 3667 3668#if 0 3669 // FIXME: Temporarily disabled because we are not properly parsing 3670 // linkage specifications on declarations, e.g., 3671 // 3672 // extern "C" const CGPoint CGPointerZero; 3673 // 3674 // C++ [dcl.init]p9: 3675 // 3676 // If no initializer is specified for an object, and the 3677 // object is of (possibly cv-qualified) non-POD class type (or 3678 // array thereof), the object shall be default-initialized; if 3679 // the object is of const-qualified type, the underlying class 3680 // type shall have a user-declared default 3681 // constructor. Otherwise, if no initializer is specified for 3682 // an object, the object and its subobjects, if any, have an 3683 // indeterminate initial value; if the object or any of its 3684 // subobjects are of const-qualified type, the program is 3685 // ill-formed. 3686 // 3687 // This isn't technically an error in C, so we don't diagnose it. 3688 // 3689 // FIXME: Actually perform the POD/user-defined default 3690 // constructor check. 3691 if (getLangOptions().CPlusPlus && 3692 Context.getCanonicalType(Type).isConstQualified() && 3693 !Var->hasExternalStorage()) 3694 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3695 << Var->getName() 3696 << SourceRange(Var->getLocation(), Var->getLocation()); 3697#endif 3698 } 3699} 3700 3701Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3702 DeclPtrTy *Group, 3703 unsigned NumDecls) { 3704 llvm::SmallVector<Decl*, 8> Decls; 3705 3706 if (DS.isTypeSpecOwned()) 3707 Decls.push_back((Decl*)DS.getTypeRep()); 3708 3709 for (unsigned i = 0; i != NumDecls; ++i) 3710 if (Decl *D = Group[i].getAs<Decl>()) 3711 Decls.push_back(D); 3712 3713 // Perform semantic analysis that depends on having fully processed both 3714 // the declarator and initializer. 3715 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3716 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3717 if (!IDecl) 3718 continue; 3719 QualType T = IDecl->getType(); 3720 3721 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3722 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3723 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3724 if (T->isDependentType()) { 3725 // If T is dependent, we should not require a complete type. 3726 // (RequireCompleteType shouldn't be called with dependent types.) 3727 // But we still can at least check if we've got an array of unspecified 3728 // size without an initializer. 3729 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3730 !IDecl->getInit()) { 3731 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3732 << T; 3733 IDecl->setInvalidDecl(); 3734 } 3735 } else if (!IDecl->isInvalidDecl()) { 3736 // If T is an incomplete array type with an initializer list that is 3737 // dependent on something, its size has not been fixed. We could attempt 3738 // to fix the size for such arrays, but we would still have to check 3739 // here for initializers containing a C++0x vararg expansion, e.g. 3740 // template <typename... Args> void f(Args... args) { 3741 // int vals[] = { args }; 3742 // } 3743 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3744 Expr *Init = IDecl->getInit(); 3745 if (IAT && Init && 3746 (Init->isTypeDependent() || Init->isValueDependent())) { 3747 // Check that the member type of the array is complete, at least. 3748 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3749 diag::err_typecheck_decl_incomplete_type)) 3750 IDecl->setInvalidDecl(); 3751 } else if (RequireCompleteType(IDecl->getLocation(), T, 3752 diag::err_typecheck_decl_incomplete_type)) 3753 IDecl->setInvalidDecl(); 3754 } 3755 } 3756 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3757 // object that has file scope without an initializer, and without a 3758 // storage-class specifier or with the storage-class specifier "static", 3759 // constitutes a tentative definition. Note: A tentative definition with 3760 // external linkage is valid (C99 6.2.2p5). 3761 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3762 if (const IncompleteArrayType *ArrayT 3763 = Context.getAsIncompleteArrayType(T)) { 3764 if (RequireCompleteType(IDecl->getLocation(), 3765 ArrayT->getElementType(), 3766 diag::err_illegal_decl_array_incomplete_type)) 3767 IDecl->setInvalidDecl(); 3768 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3769 // C99 6.9.2p3: If the declaration of an identifier for an object is 3770 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3771 // declared type shall not be an incomplete type. 3772 // NOTE: code such as the following 3773 // static struct s; 3774 // struct s { int a; }; 3775 // is accepted by gcc. Hence here we issue a warning instead of 3776 // an error and we do not invalidate the static declaration. 3777 // NOTE: to avoid multiple warnings, only check the first declaration. 3778 if (IDecl->getPreviousDeclaration() == 0) 3779 RequireCompleteType(IDecl->getLocation(), T, 3780 diag::ext_typecheck_decl_incomplete_type); 3781 } 3782 } 3783 } 3784 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3785 Decls.data(), Decls.size())); 3786} 3787 3788 3789/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3790/// to introduce parameters into function prototype scope. 3791Sema::DeclPtrTy 3792Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3793 const DeclSpec &DS = D.getDeclSpec(); 3794 3795 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3796 VarDecl::StorageClass StorageClass = VarDecl::None; 3797 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3798 StorageClass = VarDecl::Register; 3799 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3800 Diag(DS.getStorageClassSpecLoc(), 3801 diag::err_invalid_storage_class_in_func_decl); 3802 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3803 } 3804 3805 if (D.getDeclSpec().isThreadSpecified()) 3806 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3807 3808 DiagnoseFunctionSpecifiers(D); 3809 3810 // Check that there are no default arguments inside the type of this 3811 // parameter (C++ only). 3812 if (getLangOptions().CPlusPlus) 3813 CheckExtraCXXDefaultArguments(D); 3814 3815 DeclaratorInfo *DInfo = 0; 3816 TagDecl *OwnedDecl = 0; 3817 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3818 3819 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3820 // C++ [dcl.fct]p6: 3821 // Types shall not be defined in return or parameter types. 3822 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3823 << Context.getTypeDeclType(OwnedDecl); 3824 } 3825 3826 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3827 // Can this happen for params? We already checked that they don't conflict 3828 // among each other. Here they can only shadow globals, which is ok. 3829 IdentifierInfo *II = D.getIdentifier(); 3830 if (II) { 3831 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3832 if (PrevDecl->isTemplateParameter()) { 3833 // Maybe we will complain about the shadowed template parameter. 3834 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3835 // Just pretend that we didn't see the previous declaration. 3836 PrevDecl = 0; 3837 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3838 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3839 3840 // Recover by removing the name 3841 II = 0; 3842 D.SetIdentifier(0, D.getIdentifierLoc()); 3843 } 3844 } 3845 } 3846 3847 // Parameters can not be abstract class types. 3848 // For record types, this is done by the AbstractClassUsageDiagnoser once 3849 // the class has been completely parsed. 3850 if (!CurContext->isRecord() && 3851 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3852 diag::err_abstract_type_in_decl, 3853 AbstractParamType)) 3854 D.setInvalidType(true); 3855 3856 QualType T = adjustParameterType(parmDeclType); 3857 3858 ParmVarDecl *New 3859 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3860 T, DInfo, StorageClass, 0); 3861 3862 if (D.isInvalidType()) 3863 New->setInvalidDecl(); 3864 3865 // Parameter declarators cannot be interface types. All ObjC objects are 3866 // passed by reference. 3867 if (T->isObjCInterfaceType()) { 3868 Diag(D.getIdentifierLoc(), 3869 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3870 New->setInvalidDecl(); 3871 } 3872 3873 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3874 if (D.getCXXScopeSpec().isSet()) { 3875 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3876 << D.getCXXScopeSpec().getRange(); 3877 New->setInvalidDecl(); 3878 } 3879 3880 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3881 // duration shall not be qualified by an address-space qualifier." 3882 // Since all parameters have automatic store duration, they can not have 3883 // an address space. 3884 if (T.getAddressSpace() != 0) { 3885 Diag(D.getIdentifierLoc(), 3886 diag::err_arg_with_address_space); 3887 New->setInvalidDecl(); 3888 } 3889 3890 3891 // Add the parameter declaration into this scope. 3892 S->AddDecl(DeclPtrTy::make(New)); 3893 if (II) 3894 IdResolver.AddDecl(New); 3895 3896 ProcessDeclAttributes(S, New, D); 3897 3898 if (New->hasAttr<BlocksAttr>()) { 3899 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3900 } 3901 return DeclPtrTy::make(New); 3902} 3903 3904void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3905 SourceLocation LocAfterDecls) { 3906 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3907 "Not a function declarator!"); 3908 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3909 3910 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3911 // for a K&R function. 3912 if (!FTI.hasPrototype) { 3913 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3914 --i; 3915 if (FTI.ArgInfo[i].Param == 0) { 3916 llvm::SmallString<256> Code; 3917 llvm::raw_svector_ostream(Code) << " int " 3918 << FTI.ArgInfo[i].Ident->getName() 3919 << ";\n"; 3920 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3921 << FTI.ArgInfo[i].Ident 3922 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3923 3924 // Implicitly declare the argument as type 'int' for lack of a better 3925 // type. 3926 DeclSpec DS; 3927 const char* PrevSpec; // unused 3928 unsigned DiagID; // unused 3929 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3930 PrevSpec, DiagID); 3931 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3932 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3933 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3934 } 3935 } 3936 } 3937} 3938 3939Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3940 Declarator &D) { 3941 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3942 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3943 "Not a function declarator!"); 3944 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3945 3946 if (FTI.hasPrototype) { 3947 // FIXME: Diagnose arguments without names in C. 3948 } 3949 3950 Scope *ParentScope = FnBodyScope->getParent(); 3951 3952 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3953 MultiTemplateParamsArg(*this), 3954 /*IsFunctionDefinition=*/true); 3955 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3956} 3957 3958Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3959 // Clear the last template instantiation error context. 3960 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3961 3962 if (!D) 3963 return D; 3964 FunctionDecl *FD = 0; 3965 3966 if (FunctionTemplateDecl *FunTmpl 3967 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3968 FD = FunTmpl->getTemplatedDecl(); 3969 else 3970 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3971 3972 CurFunctionNeedsScopeChecking = false; 3973 3974 // See if this is a redefinition. 3975 const FunctionDecl *Definition; 3976 if (FD->getBody(Definition)) { 3977 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3978 Diag(Definition->getLocation(), diag::note_previous_definition); 3979 } 3980 3981 // Builtin functions cannot be defined. 3982 if (unsigned BuiltinID = FD->getBuiltinID()) { 3983 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3984 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3985 FD->setInvalidDecl(); 3986 } 3987 } 3988 3989 // The return type of a function definition must be complete 3990 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3991 QualType ResultType = FD->getResultType(); 3992 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3993 !FD->isInvalidDecl() && 3994 RequireCompleteType(FD->getLocation(), ResultType, 3995 diag::err_func_def_incomplete_result)) 3996 FD->setInvalidDecl(); 3997 3998 // GNU warning -Wmissing-prototypes: 3999 // Warn if a global function is defined without a previous 4000 // prototype declaration. This warning is issued even if the 4001 // definition itself provides a prototype. The aim is to detect 4002 // global functions that fail to be declared in header files. 4003 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 4004 !FD->isMain()) { 4005 bool MissingPrototype = true; 4006 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4007 Prev; Prev = Prev->getPreviousDeclaration()) { 4008 // Ignore any declarations that occur in function or method 4009 // scope, because they aren't visible from the header. 4010 if (Prev->getDeclContext()->isFunctionOrMethod()) 4011 continue; 4012 4013 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4014 break; 4015 } 4016 4017 if (MissingPrototype) 4018 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4019 } 4020 4021 if (FnBodyScope) 4022 PushDeclContext(FnBodyScope, FD); 4023 4024 // Check the validity of our function parameters 4025 CheckParmsForFunctionDef(FD); 4026 4027 // Introduce our parameters into the function scope 4028 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4029 ParmVarDecl *Param = FD->getParamDecl(p); 4030 Param->setOwningFunction(FD); 4031 4032 // If this has an identifier, add it to the scope stack. 4033 if (Param->getIdentifier() && FnBodyScope) 4034 PushOnScopeChains(Param, FnBodyScope); 4035 } 4036 4037 // Checking attributes of current function definition 4038 // dllimport attribute. 4039 if (FD->getAttr<DLLImportAttr>() && 4040 (!FD->getAttr<DLLExportAttr>())) { 4041 // dllimport attribute cannot be applied to definition. 4042 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4043 Diag(FD->getLocation(), 4044 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4045 << "dllimport"; 4046 FD->setInvalidDecl(); 4047 return DeclPtrTy::make(FD); 4048 } else { 4049 // If a symbol previously declared dllimport is later defined, the 4050 // attribute is ignored in subsequent references, and a warning is 4051 // emitted. 4052 Diag(FD->getLocation(), 4053 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4054 << FD->getNameAsCString() << "dllimport"; 4055 } 4056 } 4057 return DeclPtrTy::make(FD); 4058} 4059 4060Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4061 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4062} 4063 4064Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4065 bool IsInstantiation) { 4066 Decl *dcl = D.getAs<Decl>(); 4067 Stmt *Body = BodyArg.takeAs<Stmt>(); 4068 4069 FunctionDecl *FD = 0; 4070 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4071 if (FunTmpl) 4072 FD = FunTmpl->getTemplatedDecl(); 4073 else 4074 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4075 4076 if (FD) { 4077 FD->setBody(Body); 4078 if (FD->isMain()) 4079 // C and C++ allow for main to automagically return 0. 4080 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4081 FD->setHasImplicitReturnZero(true); 4082 else 4083 CheckFallThroughForFunctionDef(FD, Body); 4084 4085 if (!FD->isInvalidDecl()) 4086 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4087 4088 // C++ [basic.def.odr]p2: 4089 // [...] A virtual member function is used if it is not pure. [...] 4090 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4091 if (Method->isVirtual() && !Method->isPure()) 4092 MarkDeclarationReferenced(Method->getLocation(), Method); 4093 4094 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4095 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4096 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4097 MD->setBody(Body); 4098 CheckFallThroughForFunctionDef(MD, Body); 4099 MD->setEndLoc(Body->getLocEnd()); 4100 4101 if (!MD->isInvalidDecl()) 4102 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4103 } else { 4104 Body->Destroy(Context); 4105 return DeclPtrTy(); 4106 } 4107 if (!IsInstantiation) 4108 PopDeclContext(); 4109 4110 // Verify and clean out per-function state. 4111 4112 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4113 4114 // Check goto/label use. 4115 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4116 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4117 LabelStmt *L = I->second; 4118 4119 // Verify that we have no forward references left. If so, there was a goto 4120 // or address of a label taken, but no definition of it. Label fwd 4121 // definitions are indicated with a null substmt. 4122 if (L->getSubStmt() != 0) 4123 continue; 4124 4125 // Emit error. 4126 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4127 4128 // At this point, we have gotos that use the bogus label. Stitch it into 4129 // the function body so that they aren't leaked and that the AST is well 4130 // formed. 4131 if (Body == 0) { 4132 // The whole function wasn't parsed correctly, just delete this. 4133 L->Destroy(Context); 4134 continue; 4135 } 4136 4137 // Otherwise, the body is valid: we want to stitch the label decl into the 4138 // function somewhere so that it is properly owned and so that the goto 4139 // has a valid target. Do this by creating a new compound stmt with the 4140 // label in it. 4141 4142 // Give the label a sub-statement. 4143 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4144 4145 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4146 cast<CXXTryStmt>(Body)->getTryBlock() : 4147 cast<CompoundStmt>(Body); 4148 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4149 Elements.push_back(L); 4150 Compound->setStmts(Context, &Elements[0], Elements.size()); 4151 } 4152 FunctionLabelMap.clear(); 4153 4154 if (!Body) return D; 4155 4156 // Verify that that gotos and switch cases don't jump into scopes illegally. 4157 if (CurFunctionNeedsScopeChecking) 4158 DiagnoseInvalidJumps(Body); 4159 4160 // C++ constructors that have function-try-blocks can't have return 4161 // statements in the handlers of that block. (C++ [except.handle]p14) 4162 // Verify this. 4163 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4164 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4165 4166 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4167 MarkBaseAndMemberDestructorsReferenced(Destructor); 4168 4169 // If any errors have occurred, clear out any temporaries that may have 4170 // been leftover. This ensures that these temporaries won't be picked up for 4171 // deletion in some later function. 4172 if (PP.getDiagnostics().hasErrorOccurred()) 4173 ExprTemporaries.clear(); 4174 4175 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4176 return D; 4177} 4178 4179/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4180/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4181NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4182 IdentifierInfo &II, Scope *S) { 4183 // Before we produce a declaration for an implicitly defined 4184 // function, see whether there was a locally-scoped declaration of 4185 // this name as a function or variable. If so, use that 4186 // (non-visible) declaration, and complain about it. 4187 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4188 = LocallyScopedExternalDecls.find(&II); 4189 if (Pos != LocallyScopedExternalDecls.end()) { 4190 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4191 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4192 return Pos->second; 4193 } 4194 4195 // Extension in C99. Legal in C90, but warn about it. 4196 if (II.getName().startswith("__builtin_")) 4197 Diag(Loc, diag::warn_builtin_unknown) << &II; 4198 else if (getLangOptions().C99) 4199 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4200 else 4201 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4202 4203 // Set a Declarator for the implicit definition: int foo(); 4204 const char *Dummy; 4205 DeclSpec DS; 4206 unsigned DiagID; 4207 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4208 Error = Error; // Silence warning. 4209 assert(!Error && "Error setting up implicit decl!"); 4210 Declarator D(DS, Declarator::BlockContext); 4211 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4212 0, 0, false, SourceLocation(), 4213 false, 0,0,0, Loc, Loc, D), 4214 SourceLocation()); 4215 D.SetIdentifier(&II, Loc); 4216 4217 // Insert this function into translation-unit scope. 4218 4219 DeclContext *PrevDC = CurContext; 4220 CurContext = Context.getTranslationUnitDecl(); 4221 4222 FunctionDecl *FD = 4223 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4224 FD->setImplicit(); 4225 4226 CurContext = PrevDC; 4227 4228 AddKnownFunctionAttributes(FD); 4229 4230 return FD; 4231} 4232 4233/// \brief Adds any function attributes that we know a priori based on 4234/// the declaration of this function. 4235/// 4236/// These attributes can apply both to implicitly-declared builtins 4237/// (like __builtin___printf_chk) or to library-declared functions 4238/// like NSLog or printf. 4239void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4240 if (FD->isInvalidDecl()) 4241 return; 4242 4243 // If this is a built-in function, map its builtin attributes to 4244 // actual attributes. 4245 if (unsigned BuiltinID = FD->getBuiltinID()) { 4246 // Handle printf-formatting attributes. 4247 unsigned FormatIdx; 4248 bool HasVAListArg; 4249 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4250 if (!FD->getAttr<FormatAttr>()) 4251 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4252 HasVAListArg ? 0 : FormatIdx + 2)); 4253 } 4254 4255 // Mark const if we don't care about errno and that is the only 4256 // thing preventing the function from being const. This allows 4257 // IRgen to use LLVM intrinsics for such functions. 4258 if (!getLangOptions().MathErrno && 4259 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4260 if (!FD->getAttr<ConstAttr>()) 4261 FD->addAttr(::new (Context) ConstAttr()); 4262 } 4263 4264 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4265 FD->addAttr(::new (Context) NoReturnAttr()); 4266 } 4267 4268 IdentifierInfo *Name = FD->getIdentifier(); 4269 if (!Name) 4270 return; 4271 if ((!getLangOptions().CPlusPlus && 4272 FD->getDeclContext()->isTranslationUnit()) || 4273 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4274 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4275 LinkageSpecDecl::lang_c)) { 4276 // Okay: this could be a libc/libm/Objective-C function we know 4277 // about. 4278 } else 4279 return; 4280 4281 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4282 // FIXME: NSLog and NSLogv should be target specific 4283 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4284 // FIXME: We known better than our headers. 4285 const_cast<FormatAttr *>(Format)->setType("printf"); 4286 } else 4287 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4288 Name->isStr("NSLogv") ? 0 : 2)); 4289 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4290 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4291 // target-specific builtins, perhaps? 4292 if (!FD->getAttr<FormatAttr>()) 4293 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4294 Name->isStr("vasprintf") ? 0 : 3)); 4295 } 4296} 4297 4298TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4299 DeclaratorInfo *DInfo) { 4300 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4301 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4302 4303 if (!DInfo) { 4304 assert(D.isInvalidType() && "no declarator info for valid type"); 4305 DInfo = Context.getTrivialDeclaratorInfo(T); 4306 } 4307 4308 // Scope manipulation handled by caller. 4309 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4310 D.getIdentifierLoc(), 4311 D.getIdentifier(), 4312 DInfo); 4313 4314 if (const TagType *TT = T->getAs<TagType>()) { 4315 TagDecl *TD = TT->getDecl(); 4316 4317 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4318 // keep track of the TypedefDecl. 4319 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4320 TD->setTypedefForAnonDecl(NewTD); 4321 } 4322 4323 if (D.isInvalidType()) 4324 NewTD->setInvalidDecl(); 4325 return NewTD; 4326} 4327 4328 4329/// \brief Determine whether a tag with a given kind is acceptable 4330/// as a redeclaration of the given tag declaration. 4331/// 4332/// \returns true if the new tag kind is acceptable, false otherwise. 4333bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4334 TagDecl::TagKind NewTag, 4335 SourceLocation NewTagLoc, 4336 const IdentifierInfo &Name) { 4337 // C++ [dcl.type.elab]p3: 4338 // The class-key or enum keyword present in the 4339 // elaborated-type-specifier shall agree in kind with the 4340 // declaration to which the name in theelaborated-type-specifier 4341 // refers. This rule also applies to the form of 4342 // elaborated-type-specifier that declares a class-name or 4343 // friend class since it can be construed as referring to the 4344 // definition of the class. Thus, in any 4345 // elaborated-type-specifier, the enum keyword shall be used to 4346 // refer to an enumeration (7.2), the union class-keyshall be 4347 // used to refer to a union (clause 9), and either the class or 4348 // struct class-key shall be used to refer to a class (clause 9) 4349 // declared using the class or struct class-key. 4350 TagDecl::TagKind OldTag = Previous->getTagKind(); 4351 if (OldTag == NewTag) 4352 return true; 4353 4354 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4355 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4356 // Warn about the struct/class tag mismatch. 4357 bool isTemplate = false; 4358 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4359 isTemplate = Record->getDescribedClassTemplate(); 4360 4361 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4362 << (NewTag == TagDecl::TK_class) 4363 << isTemplate << &Name 4364 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4365 OldTag == TagDecl::TK_class? "class" : "struct"); 4366 Diag(Previous->getLocation(), diag::note_previous_use); 4367 return true; 4368 } 4369 return false; 4370} 4371 4372/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4373/// former case, Name will be non-null. In the later case, Name will be null. 4374/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4375/// reference/declaration/definition of a tag. 4376Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4377 SourceLocation KWLoc, const CXXScopeSpec &SS, 4378 IdentifierInfo *Name, SourceLocation NameLoc, 4379 AttributeList *Attr, AccessSpecifier AS, 4380 MultiTemplateParamsArg TemplateParameterLists, 4381 bool &OwnedDecl, bool &IsDependent) { 4382 // If this is not a definition, it must have a name. 4383 assert((Name != 0 || TUK == TUK_Definition) && 4384 "Nameless record must be a definition!"); 4385 4386 OwnedDecl = false; 4387 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4388 4389 // FIXME: Check explicit specializations more carefully. 4390 bool isExplicitSpecialization = false; 4391 if (TUK != TUK_Reference) { 4392 if (TemplateParameterList *TemplateParams 4393 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4394 (TemplateParameterList**)TemplateParameterLists.get(), 4395 TemplateParameterLists.size(), 4396 isExplicitSpecialization)) { 4397 if (TemplateParams->size() > 0) { 4398 // This is a declaration or definition of a class template (which may 4399 // be a member of another template). 4400 OwnedDecl = false; 4401 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4402 SS, Name, NameLoc, Attr, 4403 TemplateParams, 4404 AS); 4405 TemplateParameterLists.release(); 4406 return Result.get(); 4407 } else { 4408 // The "template<>" header is extraneous. 4409 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4410 << ElaboratedType::getNameForTagKind(Kind) << Name; 4411 isExplicitSpecialization = true; 4412 } 4413 } 4414 4415 TemplateParameterLists.release(); 4416 } 4417 4418 DeclContext *SearchDC = CurContext; 4419 DeclContext *DC = CurContext; 4420 bool isStdBadAlloc = false; 4421 bool Invalid = false; 4422 4423 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4424 : NotForRedeclaration); 4425 4426 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4427 4428 if (Name && SS.isNotEmpty()) { 4429 // We have a nested-name tag ('struct foo::bar'). 4430 4431 // Check for invalid 'foo::'. 4432 if (SS.isInvalid()) { 4433 Name = 0; 4434 goto CreateNewDecl; 4435 } 4436 4437 // If this is a friend or a reference to a class in a dependent 4438 // context, don't try to make a decl for it. 4439 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4440 DC = computeDeclContext(SS, false); 4441 if (!DC) { 4442 IsDependent = true; 4443 return DeclPtrTy(); 4444 } 4445 } 4446 4447 if (RequireCompleteDeclContext(SS)) 4448 return DeclPtrTy::make((Decl *)0); 4449 4450 DC = computeDeclContext(SS, true); 4451 SearchDC = DC; 4452 // Look-up name inside 'foo::'. 4453 LookupQualifiedName(Previous, DC); 4454 4455 if (Previous.isAmbiguous()) 4456 return DeclPtrTy(); 4457 4458 // A tag 'foo::bar' must already exist. 4459 if (Previous.empty()) { 4460 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4461 Name = 0; 4462 Invalid = true; 4463 goto CreateNewDecl; 4464 } 4465 } else if (Name) { 4466 // If this is a named struct, check to see if there was a previous forward 4467 // declaration or definition. 4468 // FIXME: We're looking into outer scopes here, even when we 4469 // shouldn't be. Doing so can result in ambiguities that we 4470 // shouldn't be diagnosing. 4471 LookupName(Previous, S); 4472 4473 // Note: there used to be some attempt at recovery here. 4474 if (Previous.isAmbiguous()) 4475 return DeclPtrTy(); 4476 4477 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4478 // FIXME: This makes sure that we ignore the contexts associated 4479 // with C structs, unions, and enums when looking for a matching 4480 // tag declaration or definition. See the similar lookup tweak 4481 // in Sema::LookupName; is there a better way to deal with this? 4482 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4483 SearchDC = SearchDC->getParent(); 4484 } 4485 } 4486 4487 if (Previous.isSingleResult() && 4488 Previous.getFoundDecl()->isTemplateParameter()) { 4489 // Maybe we will complain about the shadowed template parameter. 4490 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4491 // Just pretend that we didn't see the previous declaration. 4492 Previous.clear(); 4493 } 4494 4495 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4496 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4497 // This is a declaration of or a reference to "std::bad_alloc". 4498 isStdBadAlloc = true; 4499 4500 if (Previous.empty() && StdBadAlloc) { 4501 // std::bad_alloc has been implicitly declared (but made invisible to 4502 // name lookup). Fill in this implicit declaration as the previous 4503 // declaration, so that the declarations get chained appropriately. 4504 Previous.addDecl(StdBadAlloc); 4505 } 4506 } 4507 4508 if (!Previous.empty()) { 4509 assert(Previous.isSingleResult()); 4510 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4511 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4512 // If this is a use of a previous tag, or if the tag is already declared 4513 // in the same scope (so that the definition/declaration completes or 4514 // rementions the tag), reuse the decl. 4515 if (TUK == TUK_Reference || TUK == TUK_Friend || 4516 isDeclInScope(PrevDecl, SearchDC, S)) { 4517 // Make sure that this wasn't declared as an enum and now used as a 4518 // struct or something similar. 4519 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4520 bool SafeToContinue 4521 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4522 Kind != TagDecl::TK_enum); 4523 if (SafeToContinue) 4524 Diag(KWLoc, diag::err_use_with_wrong_tag) 4525 << Name 4526 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4527 PrevTagDecl->getKindName()); 4528 else 4529 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4530 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4531 4532 if (SafeToContinue) 4533 Kind = PrevTagDecl->getTagKind(); 4534 else { 4535 // Recover by making this an anonymous redefinition. 4536 Name = 0; 4537 Previous.clear(); 4538 Invalid = true; 4539 } 4540 } 4541 4542 if (!Invalid) { 4543 // If this is a use, just return the declaration we found. 4544 4545 // FIXME: In the future, return a variant or some other clue 4546 // for the consumer of this Decl to know it doesn't own it. 4547 // For our current ASTs this shouldn't be a problem, but will 4548 // need to be changed with DeclGroups. 4549 if (TUK == TUK_Reference || TUK == TUK_Friend) 4550 return DeclPtrTy::make(PrevTagDecl); 4551 4552 // Diagnose attempts to redefine a tag. 4553 if (TUK == TUK_Definition) { 4554 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4555 // If we're defining a specialization and the previous definition 4556 // is from an implicit instantiation, don't emit an error 4557 // here; we'll catch this in the general case below. 4558 if (!isExplicitSpecialization || 4559 !isa<CXXRecordDecl>(Def) || 4560 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4561 == TSK_ExplicitSpecialization) { 4562 Diag(NameLoc, diag::err_redefinition) << Name; 4563 Diag(Def->getLocation(), diag::note_previous_definition); 4564 // If this is a redefinition, recover by making this 4565 // struct be anonymous, which will make any later 4566 // references get the previous definition. 4567 Name = 0; 4568 Previous.clear(); 4569 Invalid = true; 4570 } 4571 } else { 4572 // If the type is currently being defined, complain 4573 // about a nested redefinition. 4574 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4575 if (Tag->isBeingDefined()) { 4576 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4577 Diag(PrevTagDecl->getLocation(), 4578 diag::note_previous_definition); 4579 Name = 0; 4580 Previous.clear(); 4581 Invalid = true; 4582 } 4583 } 4584 4585 // Okay, this is definition of a previously declared or referenced 4586 // tag PrevDecl. We're going to create a new Decl for it. 4587 } 4588 } 4589 // If we get here we have (another) forward declaration or we 4590 // have a definition. Just create a new decl. 4591 4592 } else { 4593 // If we get here, this is a definition of a new tag type in a nested 4594 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4595 // new decl/type. We set PrevDecl to NULL so that the entities 4596 // have distinct types. 4597 Previous.clear(); 4598 } 4599 // If we get here, we're going to create a new Decl. If PrevDecl 4600 // is non-NULL, it's a definition of the tag declared by 4601 // PrevDecl. If it's NULL, we have a new definition. 4602 } else { 4603 // PrevDecl is a namespace, template, or anything else 4604 // that lives in the IDNS_Tag identifier namespace. 4605 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4606 // The tag name clashes with a namespace name, issue an error and 4607 // recover by making this tag be anonymous. 4608 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4609 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4610 Name = 0; 4611 Previous.clear(); 4612 Invalid = true; 4613 } else { 4614 // The existing declaration isn't relevant to us; we're in a 4615 // new scope, so clear out the previous declaration. 4616 Previous.clear(); 4617 } 4618 } 4619 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4620 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4621 // C++ [basic.scope.pdecl]p5: 4622 // -- for an elaborated-type-specifier of the form 4623 // 4624 // class-key identifier 4625 // 4626 // if the elaborated-type-specifier is used in the 4627 // decl-specifier-seq or parameter-declaration-clause of a 4628 // function defined in namespace scope, the identifier is 4629 // declared as a class-name in the namespace that contains 4630 // the declaration; otherwise, except as a friend 4631 // declaration, the identifier is declared in the smallest 4632 // non-class, non-function-prototype scope that contains the 4633 // declaration. 4634 // 4635 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4636 // C structs and unions. 4637 // 4638 // GNU C also supports this behavior as part of its incomplete 4639 // enum types extension, while GNU C++ does not. 4640 // 4641 // Find the context where we'll be declaring the tag. 4642 // FIXME: We would like to maintain the current DeclContext as the 4643 // lexical context, 4644 while (SearchDC->isRecord()) 4645 SearchDC = SearchDC->getParent(); 4646 4647 // Find the scope where we'll be declaring the tag. 4648 while (S->isClassScope() || 4649 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4650 ((S->getFlags() & Scope::DeclScope) == 0) || 4651 (S->getEntity() && 4652 ((DeclContext *)S->getEntity())->isTransparentContext())) 4653 S = S->getParent(); 4654 4655 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4656 // C++ [namespace.memdef]p3: 4657 // If a friend declaration in a non-local class first declares a 4658 // class or function, the friend class or function is a member of 4659 // the innermost enclosing namespace. 4660 while (!SearchDC->isFileContext()) 4661 SearchDC = SearchDC->getParent(); 4662 4663 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4664 while (S->getEntity() != SearchDC) 4665 S = S->getParent(); 4666 } 4667 4668CreateNewDecl: 4669 4670 TagDecl *PrevDecl = 0; 4671 if (Previous.isSingleResult()) 4672 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4673 4674 // If there is an identifier, use the location of the identifier as the 4675 // location of the decl, otherwise use the location of the struct/union 4676 // keyword. 4677 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4678 4679 // Otherwise, create a new declaration. If there is a previous 4680 // declaration of the same entity, the two will be linked via 4681 // PrevDecl. 4682 TagDecl *New; 4683 4684 if (Kind == TagDecl::TK_enum) { 4685 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4686 // enum X { A, B, C } D; D should chain to X. 4687 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4688 cast_or_null<EnumDecl>(PrevDecl)); 4689 // If this is an undefined enum, warn. 4690 if (TUK != TUK_Definition && !Invalid) { 4691 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4692 : diag::ext_forward_ref_enum; 4693 Diag(Loc, DK); 4694 } 4695 } else { 4696 // struct/union/class 4697 4698 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4699 // struct X { int A; } D; D should chain to X. 4700 if (getLangOptions().CPlusPlus) { 4701 // FIXME: Look for a way to use RecordDecl for simple structs. 4702 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4703 cast_or_null<CXXRecordDecl>(PrevDecl)); 4704 4705 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4706 StdBadAlloc = cast<CXXRecordDecl>(New); 4707 } else 4708 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4709 cast_or_null<RecordDecl>(PrevDecl)); 4710 } 4711 4712 if (Kind != TagDecl::TK_enum) { 4713 // Handle #pragma pack: if the #pragma pack stack has non-default 4714 // alignment, make up a packed attribute for this decl. These 4715 // attributes are checked when the ASTContext lays out the 4716 // structure. 4717 // 4718 // It is important for implementing the correct semantics that this 4719 // happen here (in act on tag decl). The #pragma pack stack is 4720 // maintained as a result of parser callbacks which can occur at 4721 // many points during the parsing of a struct declaration (because 4722 // the #pragma tokens are effectively skipped over during the 4723 // parsing of the struct). 4724 if (unsigned Alignment = getPragmaPackAlignment()) 4725 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4726 } 4727 4728 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4729 // C++ [dcl.typedef]p3: 4730 // [...] Similarly, in a given scope, a class or enumeration 4731 // shall not be declared with the same name as a typedef-name 4732 // that is declared in that scope and refers to a type other 4733 // than the class or enumeration itself. 4734 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4735 ForRedeclaration); 4736 LookupName(Lookup, S); 4737 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4738 NamedDecl *PrevTypedefNamed = PrevTypedef; 4739 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4740 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4741 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4742 Diag(Loc, diag::err_tag_definition_of_typedef) 4743 << Context.getTypeDeclType(New) 4744 << PrevTypedef->getUnderlyingType(); 4745 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4746 Invalid = true; 4747 } 4748 } 4749 4750 // If this is a specialization of a member class (of a class template), 4751 // check the specialization. 4752 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4753 Invalid = true; 4754 4755 if (Invalid) 4756 New->setInvalidDecl(); 4757 4758 if (Attr) 4759 ProcessDeclAttributeList(S, New, Attr); 4760 4761 // If we're declaring or defining a tag in function prototype scope 4762 // in C, note that this type can only be used within the function. 4763 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4764 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4765 4766 // Set the lexical context. If the tag has a C++ scope specifier, the 4767 // lexical context will be different from the semantic context. 4768 New->setLexicalDeclContext(CurContext); 4769 4770 // Mark this as a friend decl if applicable. 4771 if (TUK == TUK_Friend) 4772 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4773 4774 // Set the access specifier. 4775 if (!Invalid && TUK != TUK_Friend) 4776 SetMemberAccessSpecifier(New, PrevDecl, AS); 4777 4778 if (TUK == TUK_Definition) 4779 New->startDefinition(); 4780 4781 // If this has an identifier, add it to the scope stack. 4782 if (TUK == TUK_Friend) { 4783 // We might be replacing an existing declaration in the lookup tables; 4784 // if so, borrow its access specifier. 4785 if (PrevDecl) 4786 New->setAccess(PrevDecl->getAccess()); 4787 4788 // Friend tag decls are visible in fairly strange ways. 4789 if (!CurContext->isDependentContext()) { 4790 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4791 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4792 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4793 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4794 } 4795 } else if (Name) { 4796 S = getNonFieldDeclScope(S); 4797 PushOnScopeChains(New, S); 4798 } else { 4799 CurContext->addDecl(New); 4800 } 4801 4802 // If this is the C FILE type, notify the AST context. 4803 if (IdentifierInfo *II = New->getIdentifier()) 4804 if (!New->isInvalidDecl() && 4805 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4806 II->isStr("FILE")) 4807 Context.setFILEDecl(New); 4808 4809 OwnedDecl = true; 4810 return DeclPtrTy::make(New); 4811} 4812 4813void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4814 AdjustDeclIfTemplate(TagD); 4815 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4816 4817 // Enter the tag context. 4818 PushDeclContext(S, Tag); 4819 4820 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4821 FieldCollector->StartClass(); 4822 4823 if (Record->getIdentifier()) { 4824 // C++ [class]p2: 4825 // [...] The class-name is also inserted into the scope of the 4826 // class itself; this is known as the injected-class-name. For 4827 // purposes of access checking, the injected-class-name is treated 4828 // as if it were a public member name. 4829 CXXRecordDecl *InjectedClassName 4830 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4831 CurContext, Record->getLocation(), 4832 Record->getIdentifier(), 4833 Record->getTagKeywordLoc(), 4834 Record); 4835 InjectedClassName->setImplicit(); 4836 InjectedClassName->setAccess(AS_public); 4837 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4838 InjectedClassName->setDescribedClassTemplate(Template); 4839 PushOnScopeChains(InjectedClassName, S); 4840 assert(InjectedClassName->isInjectedClassName() && 4841 "Broken injected-class-name"); 4842 } 4843 } 4844} 4845 4846void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4847 SourceLocation RBraceLoc) { 4848 AdjustDeclIfTemplate(TagD); 4849 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4850 Tag->setRBraceLoc(RBraceLoc); 4851 4852 if (isa<CXXRecordDecl>(Tag)) 4853 FieldCollector->FinishClass(); 4854 4855 // Exit this scope of this tag's definition. 4856 PopDeclContext(); 4857 4858 // Notify the consumer that we've defined a tag. 4859 Consumer.HandleTagDeclDefinition(Tag); 4860} 4861 4862// Note that FieldName may be null for anonymous bitfields. 4863bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4864 QualType FieldTy, const Expr *BitWidth, 4865 bool *ZeroWidth) { 4866 // Default to true; that shouldn't confuse checks for emptiness 4867 if (ZeroWidth) 4868 *ZeroWidth = true; 4869 4870 // C99 6.7.2.1p4 - verify the field type. 4871 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4872 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4873 // Handle incomplete types with specific error. 4874 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4875 return true; 4876 if (FieldName) 4877 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4878 << FieldName << FieldTy << BitWidth->getSourceRange(); 4879 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4880 << FieldTy << BitWidth->getSourceRange(); 4881 } 4882 4883 // If the bit-width is type- or value-dependent, don't try to check 4884 // it now. 4885 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4886 return false; 4887 4888 llvm::APSInt Value; 4889 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4890 return true; 4891 4892 if (Value != 0 && ZeroWidth) 4893 *ZeroWidth = false; 4894 4895 // Zero-width bitfield is ok for anonymous field. 4896 if (Value == 0 && FieldName) 4897 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4898 4899 if (Value.isSigned() && Value.isNegative()) { 4900 if (FieldName) 4901 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4902 << FieldName << Value.toString(10); 4903 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4904 << Value.toString(10); 4905 } 4906 4907 if (!FieldTy->isDependentType()) { 4908 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4909 if (Value.getZExtValue() > TypeSize) { 4910 if (FieldName) 4911 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4912 << FieldName << (unsigned)TypeSize; 4913 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4914 << (unsigned)TypeSize; 4915 } 4916 } 4917 4918 return false; 4919} 4920 4921/// ActOnField - Each field of a struct/union/class is passed into this in order 4922/// to create a FieldDecl object for it. 4923Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4924 SourceLocation DeclStart, 4925 Declarator &D, ExprTy *BitfieldWidth) { 4926 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4927 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4928 AS_public); 4929 return DeclPtrTy::make(Res); 4930} 4931 4932/// HandleField - Analyze a field of a C struct or a C++ data member. 4933/// 4934FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4935 SourceLocation DeclStart, 4936 Declarator &D, Expr *BitWidth, 4937 AccessSpecifier AS) { 4938 IdentifierInfo *II = D.getIdentifier(); 4939 SourceLocation Loc = DeclStart; 4940 if (II) Loc = D.getIdentifierLoc(); 4941 4942 DeclaratorInfo *DInfo = 0; 4943 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4944 if (getLangOptions().CPlusPlus) 4945 CheckExtraCXXDefaultArguments(D); 4946 4947 DiagnoseFunctionSpecifiers(D); 4948 4949 if (D.getDeclSpec().isThreadSpecified()) 4950 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4951 4952 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 4953 ForRedeclaration); 4954 4955 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4956 // Maybe we will complain about the shadowed template parameter. 4957 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4958 // Just pretend that we didn't see the previous declaration. 4959 PrevDecl = 0; 4960 } 4961 4962 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4963 PrevDecl = 0; 4964 4965 bool Mutable 4966 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4967 SourceLocation TSSL = D.getSourceRange().getBegin(); 4968 FieldDecl *NewFD 4969 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4970 AS, PrevDecl, &D); 4971 if (NewFD->isInvalidDecl() && PrevDecl) { 4972 // Don't introduce NewFD into scope; there's already something 4973 // with the same name in the same scope. 4974 } else if (II) { 4975 PushOnScopeChains(NewFD, S); 4976 } else 4977 Record->addDecl(NewFD); 4978 4979 return NewFD; 4980} 4981 4982/// \brief Build a new FieldDecl and check its well-formedness. 4983/// 4984/// This routine builds a new FieldDecl given the fields name, type, 4985/// record, etc. \p PrevDecl should refer to any previous declaration 4986/// with the same name and in the same scope as the field to be 4987/// created. 4988/// 4989/// \returns a new FieldDecl. 4990/// 4991/// \todo The Declarator argument is a hack. It will be removed once 4992FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4993 DeclaratorInfo *DInfo, 4994 RecordDecl *Record, SourceLocation Loc, 4995 bool Mutable, Expr *BitWidth, 4996 SourceLocation TSSL, 4997 AccessSpecifier AS, NamedDecl *PrevDecl, 4998 Declarator *D) { 4999 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5000 bool InvalidDecl = false; 5001 if (D) InvalidDecl = D->isInvalidType(); 5002 5003 // If we receive a broken type, recover by assuming 'int' and 5004 // marking this declaration as invalid. 5005 if (T.isNull()) { 5006 InvalidDecl = true; 5007 T = Context.IntTy; 5008 } 5009 5010 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5011 // than a variably modified type. 5012 if (T->isVariablyModifiedType()) { 5013 bool SizeIsNegative; 5014 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5015 SizeIsNegative); 5016 if (!FixedTy.isNull()) { 5017 Diag(Loc, diag::warn_illegal_constant_array_size); 5018 T = FixedTy; 5019 } else { 5020 if (SizeIsNegative) 5021 Diag(Loc, diag::err_typecheck_negative_array_size); 5022 else 5023 Diag(Loc, diag::err_typecheck_field_variable_size); 5024 InvalidDecl = true; 5025 } 5026 } 5027 5028 // Fields can not have abstract class types 5029 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 5030 AbstractFieldType)) 5031 InvalidDecl = true; 5032 5033 bool ZeroWidth = false; 5034 // If this is declared as a bit-field, check the bit-field. 5035 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5036 InvalidDecl = true; 5037 DeleteExpr(BitWidth); 5038 BitWidth = 0; 5039 ZeroWidth = false; 5040 } 5041 5042 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 5043 BitWidth, Mutable); 5044 if (InvalidDecl) 5045 NewFD->setInvalidDecl(); 5046 5047 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5048 Diag(Loc, diag::err_duplicate_member) << II; 5049 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5050 NewFD->setInvalidDecl(); 5051 } 5052 5053 if (getLangOptions().CPlusPlus) { 5054 QualType EltTy = Context.getBaseElementType(T); 5055 5056 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5057 5058 if (!T->isPODType()) 5059 CXXRecord->setPOD(false); 5060 if (!ZeroWidth) 5061 CXXRecord->setEmpty(false); 5062 5063 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5064 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5065 5066 if (!RDecl->hasTrivialConstructor()) 5067 CXXRecord->setHasTrivialConstructor(false); 5068 if (!RDecl->hasTrivialCopyConstructor()) 5069 CXXRecord->setHasTrivialCopyConstructor(false); 5070 if (!RDecl->hasTrivialCopyAssignment()) 5071 CXXRecord->setHasTrivialCopyAssignment(false); 5072 if (!RDecl->hasTrivialDestructor()) 5073 CXXRecord->setHasTrivialDestructor(false); 5074 5075 // C++ 9.5p1: An object of a class with a non-trivial 5076 // constructor, a non-trivial copy constructor, a non-trivial 5077 // destructor, or a non-trivial copy assignment operator 5078 // cannot be a member of a union, nor can an array of such 5079 // objects. 5080 // TODO: C++0x alters this restriction significantly. 5081 if (Record->isUnion()) { 5082 // We check for copy constructors before constructors 5083 // because otherwise we'll never get complaints about 5084 // copy constructors. 5085 5086 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5087 5088 CXXSpecialMember member; 5089 if (!RDecl->hasTrivialCopyConstructor()) 5090 member = CXXCopyConstructor; 5091 else if (!RDecl->hasTrivialConstructor()) 5092 member = CXXDefaultConstructor; 5093 else if (!RDecl->hasTrivialCopyAssignment()) 5094 member = CXXCopyAssignment; 5095 else if (!RDecl->hasTrivialDestructor()) 5096 member = CXXDestructor; 5097 else 5098 member = invalid; 5099 5100 if (member != invalid) { 5101 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5102 DiagnoseNontrivial(RT, member); 5103 NewFD->setInvalidDecl(); 5104 } 5105 } 5106 } 5107 } 5108 5109 // FIXME: We need to pass in the attributes given an AST 5110 // representation, not a parser representation. 5111 if (D) 5112 // FIXME: What to pass instead of TUScope? 5113 ProcessDeclAttributes(TUScope, NewFD, *D); 5114 5115 if (T.isObjCGCWeak()) 5116 Diag(Loc, diag::warn_attribute_weak_on_field); 5117 5118 NewFD->setAccess(AS); 5119 5120 // C++ [dcl.init.aggr]p1: 5121 // An aggregate is an array or a class (clause 9) with [...] no 5122 // private or protected non-static data members (clause 11). 5123 // A POD must be an aggregate. 5124 if (getLangOptions().CPlusPlus && 5125 (AS == AS_private || AS == AS_protected)) { 5126 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5127 CXXRecord->setAggregate(false); 5128 CXXRecord->setPOD(false); 5129 } 5130 5131 return NewFD; 5132} 5133 5134/// DiagnoseNontrivial - Given that a class has a non-trivial 5135/// special member, figure out why. 5136void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5137 QualType QT(T, 0U); 5138 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5139 5140 // Check whether the member was user-declared. 5141 switch (member) { 5142 case CXXDefaultConstructor: 5143 if (RD->hasUserDeclaredConstructor()) { 5144 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5145 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5146 const FunctionDecl *body = 0; 5147 ci->getBody(body); 5148 if (!body || 5149 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5150 SourceLocation CtorLoc = ci->getLocation(); 5151 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5152 return; 5153 } 5154 } 5155 5156 assert(0 && "found no user-declared constructors"); 5157 return; 5158 } 5159 break; 5160 5161 case CXXCopyConstructor: 5162 if (RD->hasUserDeclaredCopyConstructor()) { 5163 SourceLocation CtorLoc = 5164 RD->getCopyConstructor(Context, 0)->getLocation(); 5165 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5166 return; 5167 } 5168 break; 5169 5170 case CXXCopyAssignment: 5171 if (RD->hasUserDeclaredCopyAssignment()) { 5172 // FIXME: this should use the location of the copy 5173 // assignment, not the type. 5174 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5175 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5176 return; 5177 } 5178 break; 5179 5180 case CXXDestructor: 5181 if (RD->hasUserDeclaredDestructor()) { 5182 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5183 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5184 return; 5185 } 5186 break; 5187 } 5188 5189 typedef CXXRecordDecl::base_class_iterator base_iter; 5190 5191 // Virtual bases and members inhibit trivial copying/construction, 5192 // but not trivial destruction. 5193 if (member != CXXDestructor) { 5194 // Check for virtual bases. vbases includes indirect virtual bases, 5195 // so we just iterate through the direct bases. 5196 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5197 if (bi->isVirtual()) { 5198 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5199 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5200 return; 5201 } 5202 5203 // Check for virtual methods. 5204 typedef CXXRecordDecl::method_iterator meth_iter; 5205 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5206 ++mi) { 5207 if (mi->isVirtual()) { 5208 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5209 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5210 return; 5211 } 5212 } 5213 } 5214 5215 bool (CXXRecordDecl::*hasTrivial)() const; 5216 switch (member) { 5217 case CXXDefaultConstructor: 5218 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5219 case CXXCopyConstructor: 5220 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5221 case CXXCopyAssignment: 5222 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5223 case CXXDestructor: 5224 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5225 default: 5226 assert(0 && "unexpected special member"); return; 5227 } 5228 5229 // Check for nontrivial bases (and recurse). 5230 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5231 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5232 assert(BaseRT && "Don't know how to handle dependent bases"); 5233 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5234 if (!(BaseRecTy->*hasTrivial)()) { 5235 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5236 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5237 DiagnoseNontrivial(BaseRT, member); 5238 return; 5239 } 5240 } 5241 5242 // Check for nontrivial members (and recurse). 5243 typedef RecordDecl::field_iterator field_iter; 5244 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5245 ++fi) { 5246 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5247 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5248 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5249 5250 if (!(EltRD->*hasTrivial)()) { 5251 SourceLocation FLoc = (*fi)->getLocation(); 5252 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5253 DiagnoseNontrivial(EltRT, member); 5254 return; 5255 } 5256 } 5257 } 5258 5259 assert(0 && "found no explanation for non-trivial member"); 5260} 5261 5262/// TranslateIvarVisibility - Translate visibility from a token ID to an 5263/// AST enum value. 5264static ObjCIvarDecl::AccessControl 5265TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5266 switch (ivarVisibility) { 5267 default: assert(0 && "Unknown visitibility kind"); 5268 case tok::objc_private: return ObjCIvarDecl::Private; 5269 case tok::objc_public: return ObjCIvarDecl::Public; 5270 case tok::objc_protected: return ObjCIvarDecl::Protected; 5271 case tok::objc_package: return ObjCIvarDecl::Package; 5272 } 5273} 5274 5275/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5276/// in order to create an IvarDecl object for it. 5277Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5278 SourceLocation DeclStart, 5279 DeclPtrTy IntfDecl, 5280 Declarator &D, ExprTy *BitfieldWidth, 5281 tok::ObjCKeywordKind Visibility) { 5282 5283 IdentifierInfo *II = D.getIdentifier(); 5284 Expr *BitWidth = (Expr*)BitfieldWidth; 5285 SourceLocation Loc = DeclStart; 5286 if (II) Loc = D.getIdentifierLoc(); 5287 5288 // FIXME: Unnamed fields can be handled in various different ways, for 5289 // example, unnamed unions inject all members into the struct namespace! 5290 5291 DeclaratorInfo *DInfo = 0; 5292 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5293 5294 if (BitWidth) { 5295 // 6.7.2.1p3, 6.7.2.1p4 5296 if (VerifyBitField(Loc, II, T, BitWidth)) { 5297 D.setInvalidType(); 5298 DeleteExpr(BitWidth); 5299 BitWidth = 0; 5300 } 5301 } else { 5302 // Not a bitfield. 5303 5304 // validate II. 5305 5306 } 5307 5308 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5309 // than a variably modified type. 5310 if (T->isVariablyModifiedType()) { 5311 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5312 D.setInvalidType(); 5313 } 5314 5315 // Get the visibility (access control) for this ivar. 5316 ObjCIvarDecl::AccessControl ac = 5317 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5318 : ObjCIvarDecl::None; 5319 // Must set ivar's DeclContext to its enclosing interface. 5320 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5321 DeclContext *EnclosingContext; 5322 if (ObjCImplementationDecl *IMPDecl = 5323 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5324 // Case of ivar declared in an implementation. Context is that of its class. 5325 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5326 assert(IDecl && "No class- ActOnIvar"); 5327 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5328 } else 5329 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5330 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5331 5332 // Construct the decl. 5333 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5334 EnclosingContext, Loc, II, T, 5335 DInfo, ac, (Expr *)BitfieldWidth); 5336 5337 if (II) { 5338 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5339 ForRedeclaration); 5340 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5341 && !isa<TagDecl>(PrevDecl)) { 5342 Diag(Loc, diag::err_duplicate_member) << II; 5343 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5344 NewID->setInvalidDecl(); 5345 } 5346 } 5347 5348 // Process attributes attached to the ivar. 5349 ProcessDeclAttributes(S, NewID, D); 5350 5351 if (D.isInvalidType()) 5352 NewID->setInvalidDecl(); 5353 5354 if (II) { 5355 // FIXME: When interfaces are DeclContexts, we'll need to add 5356 // these to the interface. 5357 S->AddDecl(DeclPtrTy::make(NewID)); 5358 IdResolver.AddDecl(NewID); 5359 } 5360 5361 return DeclPtrTy::make(NewID); 5362} 5363 5364void Sema::ActOnFields(Scope* S, 5365 SourceLocation RecLoc, DeclPtrTy RecDecl, 5366 DeclPtrTy *Fields, unsigned NumFields, 5367 SourceLocation LBrac, SourceLocation RBrac, 5368 AttributeList *Attr) { 5369 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5370 assert(EnclosingDecl && "missing record or interface decl"); 5371 5372 // If the decl this is being inserted into is invalid, then it may be a 5373 // redeclaration or some other bogus case. Don't try to add fields to it. 5374 if (EnclosingDecl->isInvalidDecl()) { 5375 // FIXME: Deallocate fields? 5376 return; 5377 } 5378 5379 5380 // Verify that all the fields are okay. 5381 unsigned NumNamedMembers = 0; 5382 llvm::SmallVector<FieldDecl*, 32> RecFields; 5383 5384 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5385 for (unsigned i = 0; i != NumFields; ++i) { 5386 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5387 5388 // Get the type for the field. 5389 Type *FDTy = FD->getType().getTypePtr(); 5390 5391 if (!FD->isAnonymousStructOrUnion()) { 5392 // Remember all fields written by the user. 5393 RecFields.push_back(FD); 5394 } 5395 5396 // If the field is already invalid for some reason, don't emit more 5397 // diagnostics about it. 5398 if (FD->isInvalidDecl()) 5399 continue; 5400 5401 // C99 6.7.2.1p2: 5402 // A structure or union shall not contain a member with 5403 // incomplete or function type (hence, a structure shall not 5404 // contain an instance of itself, but may contain a pointer to 5405 // an instance of itself), except that the last member of a 5406 // structure with more than one named member may have incomplete 5407 // array type; such a structure (and any union containing, 5408 // possibly recursively, a member that is such a structure) 5409 // shall not be a member of a structure or an element of an 5410 // array. 5411 if (FDTy->isFunctionType()) { 5412 // Field declared as a function. 5413 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5414 << FD->getDeclName(); 5415 FD->setInvalidDecl(); 5416 EnclosingDecl->setInvalidDecl(); 5417 continue; 5418 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5419 Record && Record->isStruct()) { 5420 // Flexible array member. 5421 if (NumNamedMembers < 1) { 5422 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5423 << FD->getDeclName(); 5424 FD->setInvalidDecl(); 5425 EnclosingDecl->setInvalidDecl(); 5426 continue; 5427 } 5428 // Okay, we have a legal flexible array member at the end of the struct. 5429 if (Record) 5430 Record->setHasFlexibleArrayMember(true); 5431 } else if (!FDTy->isDependentType() && 5432 RequireCompleteType(FD->getLocation(), FD->getType(), 5433 diag::err_field_incomplete)) { 5434 // Incomplete type 5435 FD->setInvalidDecl(); 5436 EnclosingDecl->setInvalidDecl(); 5437 continue; 5438 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5439 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5440 // If this is a member of a union, then entire union becomes "flexible". 5441 if (Record && Record->isUnion()) { 5442 Record->setHasFlexibleArrayMember(true); 5443 } else { 5444 // If this is a struct/class and this is not the last element, reject 5445 // it. Note that GCC supports variable sized arrays in the middle of 5446 // structures. 5447 if (i != NumFields-1) 5448 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5449 << FD->getDeclName() << FD->getType(); 5450 else { 5451 // We support flexible arrays at the end of structs in 5452 // other structs as an extension. 5453 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5454 << FD->getDeclName(); 5455 if (Record) 5456 Record->setHasFlexibleArrayMember(true); 5457 } 5458 } 5459 } 5460 if (Record && FDTTy->getDecl()->hasObjectMember()) 5461 Record->setHasObjectMember(true); 5462 } else if (FDTy->isObjCInterfaceType()) { 5463 /// A field cannot be an Objective-c object 5464 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5465 FD->setInvalidDecl(); 5466 EnclosingDecl->setInvalidDecl(); 5467 continue; 5468 } else if (getLangOptions().ObjC1 && 5469 getLangOptions().getGCMode() != LangOptions::NonGC && 5470 Record && 5471 (FD->getType()->isObjCObjectPointerType() || 5472 FD->getType().isObjCGCStrong())) 5473 Record->setHasObjectMember(true); 5474 // Keep track of the number of named members. 5475 if (FD->getIdentifier()) 5476 ++NumNamedMembers; 5477 } 5478 5479 // Okay, we successfully defined 'Record'. 5480 if (Record) { 5481 Record->completeDefinition(Context); 5482 } else { 5483 ObjCIvarDecl **ClsFields = 5484 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5485 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5486 ID->setIVarList(ClsFields, RecFields.size(), Context); 5487 ID->setLocEnd(RBrac); 5488 // Add ivar's to class's DeclContext. 5489 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5490 ClsFields[i]->setLexicalDeclContext(ID); 5491 ID->addDecl(ClsFields[i]); 5492 } 5493 // Must enforce the rule that ivars in the base classes may not be 5494 // duplicates. 5495 if (ID->getSuperClass()) { 5496 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5497 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5498 ObjCIvarDecl* Ivar = (*IVI); 5499 5500 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5501 ObjCIvarDecl* prevIvar = 5502 ID->getSuperClass()->lookupInstanceVariable(II); 5503 if (prevIvar) { 5504 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5505 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5506 } 5507 } 5508 } 5509 } 5510 } else if (ObjCImplementationDecl *IMPDecl = 5511 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5512 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5513 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5514 // Ivar declared in @implementation never belongs to the implementation. 5515 // Only it is in implementation's lexical context. 5516 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5517 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5518 } 5519 } 5520 5521 if (Attr) 5522 ProcessDeclAttributeList(S, Record, Attr); 5523} 5524 5525EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5526 EnumConstantDecl *LastEnumConst, 5527 SourceLocation IdLoc, 5528 IdentifierInfo *Id, 5529 ExprArg val) { 5530 Expr *Val = (Expr *)val.get(); 5531 5532 llvm::APSInt EnumVal(32); 5533 QualType EltTy; 5534 if (Val) { 5535 if (Val->isTypeDependent()) 5536 EltTy = Context.DependentTy; 5537 else { 5538 // Make sure to promote the operand type to int. 5539 UsualUnaryConversions(Val); 5540 if (Val != val.get()) { 5541 val.release(); 5542 val = Val; 5543 } 5544 5545 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5546 SourceLocation ExpLoc; 5547 if (!Val->isValueDependent() && 5548 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5549 Val = 0; 5550 } else { 5551 EltTy = Val->getType(); 5552 } 5553 } 5554 } 5555 5556 if (!Val) { 5557 if (LastEnumConst) { 5558 // Assign the last value + 1. 5559 EnumVal = LastEnumConst->getInitVal(); 5560 ++EnumVal; 5561 5562 // Check for overflow on increment. 5563 if (EnumVal < LastEnumConst->getInitVal()) 5564 Diag(IdLoc, diag::warn_enum_value_overflow); 5565 5566 EltTy = LastEnumConst->getType(); 5567 } else { 5568 // First value, set to zero. 5569 EltTy = Context.IntTy; 5570 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5571 } 5572 } 5573 5574 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5575 5576 val.release(); 5577 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5578 Val, EnumVal); 5579} 5580 5581 5582Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5583 DeclPtrTy lastEnumConst, 5584 SourceLocation IdLoc, 5585 IdentifierInfo *Id, 5586 SourceLocation EqualLoc, ExprTy *val) { 5587 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5588 EnumConstantDecl *LastEnumConst = 5589 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5590 Expr *Val = static_cast<Expr*>(val); 5591 5592 // The scope passed in may not be a decl scope. Zip up the scope tree until 5593 // we find one that is. 5594 S = getNonFieldDeclScope(S); 5595 5596 // Verify that there isn't already something declared with this name in this 5597 // scope. 5598 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5599 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5600 // Maybe we will complain about the shadowed template parameter. 5601 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5602 // Just pretend that we didn't see the previous declaration. 5603 PrevDecl = 0; 5604 } 5605 5606 if (PrevDecl) { 5607 // When in C++, we may get a TagDecl with the same name; in this case the 5608 // enum constant will 'hide' the tag. 5609 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5610 "Received TagDecl when not in C++!"); 5611 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5612 if (isa<EnumConstantDecl>(PrevDecl)) 5613 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5614 else 5615 Diag(IdLoc, diag::err_redefinition) << Id; 5616 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5617 if (Val) Val->Destroy(Context); 5618 return DeclPtrTy(); 5619 } 5620 } 5621 5622 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5623 IdLoc, Id, Owned(Val)); 5624 5625 // Register this decl in the current scope stack. 5626 if (New) 5627 PushOnScopeChains(New, S); 5628 5629 return DeclPtrTy::make(New); 5630} 5631 5632void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5633 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5634 DeclPtrTy *Elements, unsigned NumElements, 5635 Scope *S, AttributeList *Attr) { 5636 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5637 QualType EnumType = Context.getTypeDeclType(Enum); 5638 5639 if (Attr) 5640 ProcessDeclAttributeList(S, Enum, Attr); 5641 5642 // TODO: If the result value doesn't fit in an int, it must be a long or long 5643 // long value. ISO C does not support this, but GCC does as an extension, 5644 // emit a warning. 5645 unsigned IntWidth = Context.Target.getIntWidth(); 5646 unsigned CharWidth = Context.Target.getCharWidth(); 5647 unsigned ShortWidth = Context.Target.getShortWidth(); 5648 5649 // Verify that all the values are okay, compute the size of the values, and 5650 // reverse the list. 5651 unsigned NumNegativeBits = 0; 5652 unsigned NumPositiveBits = 0; 5653 5654 // Keep track of whether all elements have type int. 5655 bool AllElementsInt = true; 5656 5657 for (unsigned i = 0; i != NumElements; ++i) { 5658 EnumConstantDecl *ECD = 5659 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5660 if (!ECD) continue; // Already issued a diagnostic. 5661 5662 // If the enum value doesn't fit in an int, emit an extension warning. 5663 const llvm::APSInt &InitVal = ECD->getInitVal(); 5664 assert(InitVal.getBitWidth() >= IntWidth && 5665 "Should have promoted value to int"); 5666 if (InitVal.getBitWidth() > IntWidth) { 5667 llvm::APSInt V(InitVal); 5668 V.trunc(IntWidth); 5669 V.extend(InitVal.getBitWidth()); 5670 if (V != InitVal) 5671 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5672 << InitVal.toString(10); 5673 } 5674 5675 // Keep track of the size of positive and negative values. 5676 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5677 NumPositiveBits = std::max(NumPositiveBits, 5678 (unsigned)InitVal.getActiveBits()); 5679 else 5680 NumNegativeBits = std::max(NumNegativeBits, 5681 (unsigned)InitVal.getMinSignedBits()); 5682 5683 // Keep track of whether every enum element has type int (very commmon). 5684 if (AllElementsInt) 5685 AllElementsInt = ECD->getType() == Context.IntTy; 5686 } 5687 5688 // Figure out the type that should be used for this enum. 5689 // FIXME: Support -fshort-enums. 5690 QualType BestType; 5691 unsigned BestWidth; 5692 5693 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5694 5695 if (NumNegativeBits) { 5696 // If there is a negative value, figure out the smallest integer type (of 5697 // int/long/longlong) that fits. 5698 // If it's packed, check also if it fits a char or a short. 5699 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5700 BestType = Context.SignedCharTy; 5701 BestWidth = CharWidth; 5702 } else if (Packed && NumNegativeBits <= ShortWidth && 5703 NumPositiveBits < ShortWidth) { 5704 BestType = Context.ShortTy; 5705 BestWidth = ShortWidth; 5706 } 5707 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5708 BestType = Context.IntTy; 5709 BestWidth = IntWidth; 5710 } else { 5711 BestWidth = Context.Target.getLongWidth(); 5712 5713 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5714 BestType = Context.LongTy; 5715 else { 5716 BestWidth = Context.Target.getLongLongWidth(); 5717 5718 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5719 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5720 BestType = Context.LongLongTy; 5721 } 5722 } 5723 } else { 5724 // If there is no negative value, figure out which of uint, ulong, ulonglong 5725 // fits. 5726 // If it's packed, check also if it fits a char or a short. 5727 if (Packed && NumPositiveBits <= CharWidth) { 5728 BestType = Context.UnsignedCharTy; 5729 BestWidth = CharWidth; 5730 } else if (Packed && NumPositiveBits <= ShortWidth) { 5731 BestType = Context.UnsignedShortTy; 5732 BestWidth = ShortWidth; 5733 } 5734 else if (NumPositiveBits <= IntWidth) { 5735 BestType = Context.UnsignedIntTy; 5736 BestWidth = IntWidth; 5737 } else if (NumPositiveBits <= 5738 (BestWidth = Context.Target.getLongWidth())) { 5739 BestType = Context.UnsignedLongTy; 5740 } else { 5741 BestWidth = Context.Target.getLongLongWidth(); 5742 assert(NumPositiveBits <= BestWidth && 5743 "How could an initializer get larger than ULL?"); 5744 BestType = Context.UnsignedLongLongTy; 5745 } 5746 } 5747 5748 // Loop over all of the enumerator constants, changing their types to match 5749 // the type of the enum if needed. 5750 for (unsigned i = 0; i != NumElements; ++i) { 5751 EnumConstantDecl *ECD = 5752 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5753 if (!ECD) continue; // Already issued a diagnostic. 5754 5755 // Standard C says the enumerators have int type, but we allow, as an 5756 // extension, the enumerators to be larger than int size. If each 5757 // enumerator value fits in an int, type it as an int, otherwise type it the 5758 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5759 // that X has type 'int', not 'unsigned'. 5760 if (ECD->getType() == Context.IntTy) { 5761 // Make sure the init value is signed. 5762 llvm::APSInt IV = ECD->getInitVal(); 5763 IV.setIsSigned(true); 5764 ECD->setInitVal(IV); 5765 5766 if (getLangOptions().CPlusPlus) 5767 // C++ [dcl.enum]p4: Following the closing brace of an 5768 // enum-specifier, each enumerator has the type of its 5769 // enumeration. 5770 ECD->setType(EnumType); 5771 continue; // Already int type. 5772 } 5773 5774 // Determine whether the value fits into an int. 5775 llvm::APSInt InitVal = ECD->getInitVal(); 5776 bool FitsInInt; 5777 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5778 FitsInInt = InitVal.getActiveBits() < IntWidth; 5779 else 5780 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5781 5782 // If it fits into an integer type, force it. Otherwise force it to match 5783 // the enum decl type. 5784 QualType NewTy; 5785 unsigned NewWidth; 5786 bool NewSign; 5787 if (FitsInInt) { 5788 NewTy = Context.IntTy; 5789 NewWidth = IntWidth; 5790 NewSign = true; 5791 } else if (ECD->getType() == BestType) { 5792 // Already the right type! 5793 if (getLangOptions().CPlusPlus) 5794 // C++ [dcl.enum]p4: Following the closing brace of an 5795 // enum-specifier, each enumerator has the type of its 5796 // enumeration. 5797 ECD->setType(EnumType); 5798 continue; 5799 } else { 5800 NewTy = BestType; 5801 NewWidth = BestWidth; 5802 NewSign = BestType->isSignedIntegerType(); 5803 } 5804 5805 // Adjust the APSInt value. 5806 InitVal.extOrTrunc(NewWidth); 5807 InitVal.setIsSigned(NewSign); 5808 ECD->setInitVal(InitVal); 5809 5810 // Adjust the Expr initializer and type. 5811 if (ECD->getInitExpr()) 5812 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5813 CastExpr::CK_IntegralCast, 5814 ECD->getInitExpr(), 5815 /*isLvalue=*/false)); 5816 if (getLangOptions().CPlusPlus) 5817 // C++ [dcl.enum]p4: Following the closing brace of an 5818 // enum-specifier, each enumerator has the type of its 5819 // enumeration. 5820 ECD->setType(EnumType); 5821 else 5822 ECD->setType(NewTy); 5823 } 5824 5825 Enum->completeDefinition(Context, BestType); 5826} 5827 5828Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5829 ExprArg expr) { 5830 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5831 5832 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5833 Loc, AsmString); 5834 CurContext->addDecl(New); 5835 return DeclPtrTy::make(New); 5836} 5837 5838void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5839 SourceLocation PragmaLoc, 5840 SourceLocation NameLoc) { 5841 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5842 5843 if (PrevDecl) { 5844 PrevDecl->addAttr(::new (Context) WeakAttr()); 5845 } else { 5846 (void)WeakUndeclaredIdentifiers.insert( 5847 std::pair<IdentifierInfo*,WeakInfo> 5848 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5849 } 5850} 5851 5852void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5853 IdentifierInfo* AliasName, 5854 SourceLocation PragmaLoc, 5855 SourceLocation NameLoc, 5856 SourceLocation AliasNameLoc) { 5857 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5858 WeakInfo W = WeakInfo(Name, NameLoc); 5859 5860 if (PrevDecl) { 5861 if (!PrevDecl->hasAttr<AliasAttr>()) 5862 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5863 DeclApplyPragmaWeak(TUScope, ND, W); 5864 } else { 5865 (void)WeakUndeclaredIdentifiers.insert( 5866 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5867 } 5868} 5869