SemaDecl.cpp revision 2c3aa2aeb55fc7d5a15eec89af13a481d290e15a
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/Analysis/CFG.h" 21#include "clang/AST/CXXInheritance.h" 22#include "clang/AST/DeclObjC.h" 23#include "clang/AST/DeclTemplate.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/StmtCXX.h" 26#include "clang/AST/StmtObjC.h" 27#include "clang/Parse/DeclSpec.h" 28#include "clang/Parse/ParseDiagnostic.h" 29#include "clang/Parse/Template.h" 30#include "clang/Basic/PartialDiagnostic.h" 31#include "clang/Basic/SourceManager.h" 32#include "clang/Basic/TargetInfo.h" 33// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 34#include "clang/Lex/Preprocessor.h" 35#include "clang/Lex/HeaderSearch.h" 36#include "llvm/ADT/BitVector.h" 37#include "llvm/ADT/STLExtras.h" 38#include <algorithm> 39#include <cstring> 40#include <functional> 41#include <queue> 42using namespace clang; 43 44/// getDeclName - Return a pretty name for the specified decl if possible, or 45/// an empty string if not. This is used for pretty crash reporting. 46std::string Sema::getDeclName(DeclPtrTy d) { 47 Decl *D = d.getAs<Decl>(); 48 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 49 return DN->getQualifiedNameAsString(); 50 return ""; 51} 52 53Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 54 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 55} 56 57/// \brief If the identifier refers to a type name within this scope, 58/// return the declaration of that type. 59/// 60/// This routine performs ordinary name lookup of the identifier II 61/// within the given scope, with optional C++ scope specifier SS, to 62/// determine whether the name refers to a type. If so, returns an 63/// opaque pointer (actually a QualType) corresponding to that 64/// type. Otherwise, returns NULL. 65/// 66/// If name lookup results in an ambiguity, this routine will complain 67/// and then return NULL. 68Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 69 Scope *S, const CXXScopeSpec *SS, 70 bool isClassName, 71 TypeTy *ObjectTypePtr) { 72 // Determine where we will perform name lookup. 73 DeclContext *LookupCtx = 0; 74 if (ObjectTypePtr) { 75 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 76 if (ObjectType->isRecordType()) 77 LookupCtx = computeDeclContext(ObjectType); 78 } else if (SS && SS->isSet()) { 79 LookupCtx = computeDeclContext(*SS, false); 80 81 if (!LookupCtx) { 82 if (isDependentScopeSpecifier(*SS)) { 83 // C++ [temp.res]p3: 84 // A qualified-id that refers to a type and in which the 85 // nested-name-specifier depends on a template-parameter (14.6.2) 86 // shall be prefixed by the keyword typename to indicate that the 87 // qualified-id denotes a type, forming an 88 // elaborated-type-specifier (7.1.5.3). 89 // 90 // We therefore do not perform any name lookup if the result would 91 // refer to a member of an unknown specialization. 92 if (!isClassName) 93 return 0; 94 95 // We know from the grammar that this name refers to a type, so build a 96 // TypenameType node to describe the type. 97 // FIXME: Record somewhere that this TypenameType node has no "typename" 98 // keyword associated with it. 99 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 100 II, SS->getRange()).getAsOpaquePtr(); 101 } 102 103 return 0; 104 } 105 106 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 107 return 0; 108 } 109 110 LookupResult Result(*this, &II, NameLoc, LookupOrdinaryName); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 return 0; 138 139 case LookupResult::Ambiguous: 140 // Recover from type-hiding ambiguities by hiding the type. We'll 141 // do the lookup again when looking for an object, and we can 142 // diagnose the error then. If we don't do this, then the error 143 // about hiding the type will be immediately followed by an error 144 // that only makes sense if the identifier was treated like a type. 145 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 146 Result.suppressDiagnostics(); 147 return 0; 148 } 149 150 // Look to see if we have a type anywhere in the list of results. 151 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 152 Res != ResEnd; ++Res) { 153 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 154 if (!IIDecl || 155 (*Res)->getLocation().getRawEncoding() < 156 IIDecl->getLocation().getRawEncoding()) 157 IIDecl = *Res; 158 } 159 } 160 161 if (!IIDecl) { 162 // None of the entities we found is a type, so there is no way 163 // to even assume that the result is a type. In this case, don't 164 // complain about the ambiguity. The parser will either try to 165 // perform this lookup again (e.g., as an object name), which 166 // will produce the ambiguity, or will complain that it expected 167 // a type name. 168 Result.suppressDiagnostics(); 169 return 0; 170 } 171 172 // We found a type within the ambiguous lookup; diagnose the 173 // ambiguity and then return that type. This might be the right 174 // answer, or it might not be, but it suppresses any attempt to 175 // perform the name lookup again. 176 break; 177 178 case LookupResult::Found: 179 IIDecl = Result.getFoundDecl(); 180 break; 181 } 182 183 assert(IIDecl && "Didn't find decl"); 184 185 QualType T; 186 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 187 DiagnoseUseOfDecl(IIDecl, NameLoc); 188 189 // C++ [temp.local]p2: 190 // Within the scope of a class template specialization or 191 // partial specialization, when the injected-class-name is 192 // not followed by a <, it is equivalent to the 193 // injected-class-name followed by the template-argument s 194 // of the class template specialization or partial 195 // specialization enclosed in <>. 196 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 197 if (RD->isInjectedClassName()) 198 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 199 T = Template->getInjectedClassNameType(Context); 200 201 if (T.isNull()) 202 T = Context.getTypeDeclType(TD); 203 204 if (SS) 205 T = getQualifiedNameType(*SS, T); 206 207 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 208 T = Context.getObjCInterfaceType(IDecl); 209 } else if (UnresolvedUsingTypenameDecl *UUDecl = 210 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 211 // FIXME: preserve source structure information. 212 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 213 } else { 214 // If it's not plausibly a type, suppress diagnostics. 215 Result.suppressDiagnostics(); 216 return 0; 217 } 218 219 return T.getAsOpaquePtr(); 220} 221 222/// isTagName() - This method is called *for error recovery purposes only* 223/// to determine if the specified name is a valid tag name ("struct foo"). If 224/// so, this returns the TST for the tag corresponding to it (TST_enum, 225/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 226/// where the user forgot to specify the tag. 227DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 228 // Do a tag name lookup in this scope. 229 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 230 LookupName(R, S, false); 231 R.suppressDiagnostics(); 232 if (R.getResultKind() == LookupResult::Found) 233 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 234 switch (TD->getTagKind()) { 235 case TagDecl::TK_struct: return DeclSpec::TST_struct; 236 case TagDecl::TK_union: return DeclSpec::TST_union; 237 case TagDecl::TK_class: return DeclSpec::TST_class; 238 case TagDecl::TK_enum: return DeclSpec::TST_enum; 239 } 240 } 241 242 return DeclSpec::TST_unspecified; 243} 244 245bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 246 SourceLocation IILoc, 247 Scope *S, 248 const CXXScopeSpec *SS, 249 TypeTy *&SuggestedType) { 250 // We don't have anything to suggest (yet). 251 SuggestedType = 0; 252 253 // FIXME: Should we move the logic that tries to recover from a missing tag 254 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 255 256 if (!SS) 257 Diag(IILoc, diag::err_unknown_typename) << &II; 258 else if (DeclContext *DC = computeDeclContext(*SS, false)) 259 Diag(IILoc, diag::err_typename_nested_not_found) 260 << &II << DC << SS->getRange(); 261 else if (isDependentScopeSpecifier(*SS)) { 262 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 263 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 264 << SourceRange(SS->getRange().getBegin(), IILoc) 265 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 266 "typename "); 267 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 268 } else { 269 assert(SS && SS->isInvalid() && 270 "Invalid scope specifier has already been diagnosed"); 271 } 272 273 return true; 274} 275 276// Determines the context to return to after temporarily entering a 277// context. This depends in an unnecessarily complicated way on the 278// exact ordering of callbacks from the parser. 279DeclContext *Sema::getContainingDC(DeclContext *DC) { 280 281 // Functions defined inline within classes aren't parsed until we've 282 // finished parsing the top-level class, so the top-level class is 283 // the context we'll need to return to. 284 if (isa<FunctionDecl>(DC)) { 285 DC = DC->getLexicalParent(); 286 287 // A function not defined within a class will always return to its 288 // lexical context. 289 if (!isa<CXXRecordDecl>(DC)) 290 return DC; 291 292 // A C++ inline method/friend is parsed *after* the topmost class 293 // it was declared in is fully parsed ("complete"); the topmost 294 // class is the context we need to return to. 295 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 296 DC = RD; 297 298 // Return the declaration context of the topmost class the inline method is 299 // declared in. 300 return DC; 301 } 302 303 if (isa<ObjCMethodDecl>(DC)) 304 return Context.getTranslationUnitDecl(); 305 306 return DC->getLexicalParent(); 307} 308 309void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 310 assert(getContainingDC(DC) == CurContext && 311 "The next DeclContext should be lexically contained in the current one."); 312 CurContext = DC; 313 S->setEntity(DC); 314} 315 316void Sema::PopDeclContext() { 317 assert(CurContext && "DeclContext imbalance!"); 318 319 CurContext = getContainingDC(CurContext); 320} 321 322/// EnterDeclaratorContext - Used when we must lookup names in the context 323/// of a declarator's nested name specifier. 324void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 325 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 326 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 327 CurContext = DC; 328 assert(CurContext && "No context?"); 329 S->setEntity(CurContext); 330} 331 332void Sema::ExitDeclaratorContext(Scope *S) { 333 S->setEntity(PreDeclaratorDC); 334 PreDeclaratorDC = 0; 335 336 // Reset CurContext to the nearest enclosing context. 337 while (!S->getEntity() && S->getParent()) 338 S = S->getParent(); 339 CurContext = static_cast<DeclContext*>(S->getEntity()); 340 assert(CurContext && "No context?"); 341} 342 343/// \brief Determine whether we allow overloading of the function 344/// PrevDecl with another declaration. 345/// 346/// This routine determines whether overloading is possible, not 347/// whether some new function is actually an overload. It will return 348/// true in C++ (where we can always provide overloads) or, as an 349/// extension, in C when the previous function is already an 350/// overloaded function declaration or has the "overloadable" 351/// attribute. 352static bool AllowOverloadingOfFunction(LookupResult &Previous, 353 ASTContext &Context) { 354 if (Context.getLangOptions().CPlusPlus) 355 return true; 356 357 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 358 return true; 359 360 return (Previous.getResultKind() == LookupResult::Found 361 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 362} 363 364/// Add this decl to the scope shadowed decl chains. 365void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 366 // Move up the scope chain until we find the nearest enclosing 367 // non-transparent context. The declaration will be introduced into this 368 // scope. 369 while (S->getEntity() && 370 ((DeclContext *)S->getEntity())->isTransparentContext()) 371 S = S->getParent(); 372 373 // Add scoped declarations into their context, so that they can be 374 // found later. Declarations without a context won't be inserted 375 // into any context. 376 if (AddToContext) 377 CurContext->addDecl(D); 378 379 // Out-of-line function and variable definitions should not be pushed into 380 // scope. 381 if ((isa<FunctionTemplateDecl>(D) && 382 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 383 (isa<FunctionDecl>(D) && 384 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 385 cast<FunctionDecl>(D)->isOutOfLine())) || 386 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 387 return; 388 389 // If this replaces anything in the current scope, 390 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 391 IEnd = IdResolver.end(); 392 for (; I != IEnd; ++I) { 393 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 394 S->RemoveDecl(DeclPtrTy::make(*I)); 395 IdResolver.RemoveDecl(*I); 396 397 // Should only need to replace one decl. 398 break; 399 } 400 } 401 402 S->AddDecl(DeclPtrTy::make(D)); 403 IdResolver.AddDecl(D); 404} 405 406bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 407 return IdResolver.isDeclInScope(D, Ctx, Context, S); 408} 409 410static bool isOutOfScopePreviousDeclaration(NamedDecl *, 411 DeclContext*, 412 ASTContext&); 413 414/// Filters out lookup results that don't fall within the given scope 415/// as determined by isDeclInScope. 416static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 417 DeclContext *Ctx, Scope *S, 418 bool ConsiderLinkage) { 419 LookupResult::Filter F = R.makeFilter(); 420 while (F.hasNext()) { 421 NamedDecl *D = F.next(); 422 423 if (SemaRef.isDeclInScope(D, Ctx, S)) 424 continue; 425 426 if (ConsiderLinkage && 427 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 428 continue; 429 430 F.erase(); 431 } 432 433 F.done(); 434} 435 436static bool isUsingDecl(NamedDecl *D) { 437 return isa<UsingShadowDecl>(D) || 438 isa<UnresolvedUsingTypenameDecl>(D) || 439 isa<UnresolvedUsingValueDecl>(D); 440} 441 442/// Removes using shadow declarations from the lookup results. 443static void RemoveUsingDecls(LookupResult &R) { 444 LookupResult::Filter F = R.makeFilter(); 445 while (F.hasNext()) 446 if (isUsingDecl(F.next())) 447 F.erase(); 448 449 F.done(); 450} 451 452static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 453 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 454 return false; 455 456 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 457 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 458 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 459 if (!RD->hasTrivialConstructor()) 460 return false; 461 if (!RD->hasTrivialDestructor()) 462 return false; 463 } 464 } 465 } 466 467 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 468 !isa<ImplicitParamDecl>(D) && 469 D->getDeclContext()->isFunctionOrMethod()); 470} 471 472void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 473 if (S->decl_empty()) return; 474 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 475 "Scope shouldn't contain decls!"); 476 477 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 478 I != E; ++I) { 479 Decl *TmpD = (*I).getAs<Decl>(); 480 assert(TmpD && "This decl didn't get pushed??"); 481 482 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 483 NamedDecl *D = cast<NamedDecl>(TmpD); 484 485 if (!D->getDeclName()) continue; 486 487 // Diagnose unused variables in this scope. 488 if (ShouldDiagnoseUnusedDecl(D)) 489 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 490 491 // Remove this name from our lexical scope. 492 IdResolver.RemoveDecl(D); 493 } 494} 495 496/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 497/// return 0 if one not found. 498ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 499 // The third "scope" argument is 0 since we aren't enabling lazy built-in 500 // creation from this context. 501 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 502 503 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 504} 505 506/// getNonFieldDeclScope - Retrieves the innermost scope, starting 507/// from S, where a non-field would be declared. This routine copes 508/// with the difference between C and C++ scoping rules in structs and 509/// unions. For example, the following code is well-formed in C but 510/// ill-formed in C++: 511/// @code 512/// struct S6 { 513/// enum { BAR } e; 514/// }; 515/// 516/// void test_S6() { 517/// struct S6 a; 518/// a.e = BAR; 519/// } 520/// @endcode 521/// For the declaration of BAR, this routine will return a different 522/// scope. The scope S will be the scope of the unnamed enumeration 523/// within S6. In C++, this routine will return the scope associated 524/// with S6, because the enumeration's scope is a transparent 525/// context but structures can contain non-field names. In C, this 526/// routine will return the translation unit scope, since the 527/// enumeration's scope is a transparent context and structures cannot 528/// contain non-field names. 529Scope *Sema::getNonFieldDeclScope(Scope *S) { 530 while (((S->getFlags() & Scope::DeclScope) == 0) || 531 (S->getEntity() && 532 ((DeclContext *)S->getEntity())->isTransparentContext()) || 533 (S->isClassScope() && !getLangOptions().CPlusPlus)) 534 S = S->getParent(); 535 return S; 536} 537 538void Sema::InitBuiltinVaListType() { 539 if (!Context.getBuiltinVaListType().isNull()) 540 return; 541 542 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 543 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 544 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 545 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 546} 547 548/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 549/// file scope. lazily create a decl for it. ForRedeclaration is true 550/// if we're creating this built-in in anticipation of redeclaring the 551/// built-in. 552NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 553 Scope *S, bool ForRedeclaration, 554 SourceLocation Loc) { 555 Builtin::ID BID = (Builtin::ID)bid; 556 557 if (Context.BuiltinInfo.hasVAListUse(BID)) 558 InitBuiltinVaListType(); 559 560 ASTContext::GetBuiltinTypeError Error; 561 QualType R = Context.GetBuiltinType(BID, Error); 562 switch (Error) { 563 case ASTContext::GE_None: 564 // Okay 565 break; 566 567 case ASTContext::GE_Missing_stdio: 568 if (ForRedeclaration) 569 Diag(Loc, diag::err_implicit_decl_requires_stdio) 570 << Context.BuiltinInfo.GetName(BID); 571 return 0; 572 573 case ASTContext::GE_Missing_setjmp: 574 if (ForRedeclaration) 575 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 576 << Context.BuiltinInfo.GetName(BID); 577 return 0; 578 } 579 580 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 581 Diag(Loc, diag::ext_implicit_lib_function_decl) 582 << Context.BuiltinInfo.GetName(BID) 583 << R; 584 if (Context.BuiltinInfo.getHeaderName(BID) && 585 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 586 != Diagnostic::Ignored) 587 Diag(Loc, diag::note_please_include_header) 588 << Context.BuiltinInfo.getHeaderName(BID) 589 << Context.BuiltinInfo.GetName(BID); 590 } 591 592 FunctionDecl *New = FunctionDecl::Create(Context, 593 Context.getTranslationUnitDecl(), 594 Loc, II, R, /*TInfo=*/0, 595 FunctionDecl::Extern, false, 596 /*hasPrototype=*/true); 597 New->setImplicit(); 598 599 // Create Decl objects for each parameter, adding them to the 600 // FunctionDecl. 601 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 602 llvm::SmallVector<ParmVarDecl*, 16> Params; 603 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 604 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 605 FT->getArgType(i), /*TInfo=*/0, 606 VarDecl::None, 0)); 607 New->setParams(Context, Params.data(), Params.size()); 608 } 609 610 AddKnownFunctionAttributes(New); 611 612 // TUScope is the translation-unit scope to insert this function into. 613 // FIXME: This is hideous. We need to teach PushOnScopeChains to 614 // relate Scopes to DeclContexts, and probably eliminate CurContext 615 // entirely, but we're not there yet. 616 DeclContext *SavedContext = CurContext; 617 CurContext = Context.getTranslationUnitDecl(); 618 PushOnScopeChains(New, TUScope); 619 CurContext = SavedContext; 620 return New; 621} 622 623/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 624/// same name and scope as a previous declaration 'Old'. Figure out 625/// how to resolve this situation, merging decls or emitting 626/// diagnostics as appropriate. If there was an error, set New to be invalid. 627/// 628void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 629 // If the new decl is known invalid already, don't bother doing any 630 // merging checks. 631 if (New->isInvalidDecl()) return; 632 633 // Allow multiple definitions for ObjC built-in typedefs. 634 // FIXME: Verify the underlying types are equivalent! 635 if (getLangOptions().ObjC1) { 636 const IdentifierInfo *TypeID = New->getIdentifier(); 637 switch (TypeID->getLength()) { 638 default: break; 639 case 2: 640 if (!TypeID->isStr("id")) 641 break; 642 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 643 // Install the built-in type for 'id', ignoring the current definition. 644 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 645 return; 646 case 5: 647 if (!TypeID->isStr("Class")) 648 break; 649 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 650 // Install the built-in type for 'Class', ignoring the current definition. 651 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 652 return; 653 case 3: 654 if (!TypeID->isStr("SEL")) 655 break; 656 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 657 // Install the built-in type for 'SEL', ignoring the current definition. 658 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 659 return; 660 case 8: 661 if (!TypeID->isStr("Protocol")) 662 break; 663 Context.setObjCProtoType(New->getUnderlyingType()); 664 return; 665 } 666 // Fall through - the typedef name was not a builtin type. 667 } 668 669 // Verify the old decl was also a type. 670 TypeDecl *Old = 0; 671 if (!OldDecls.isSingleResult() || 672 !(Old = dyn_cast<TypeDecl>(OldDecls.getFoundDecl()))) { 673 Diag(New->getLocation(), diag::err_redefinition_different_kind) 674 << New->getDeclName(); 675 676 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 677 if (OldD->getLocation().isValid()) 678 Diag(OldD->getLocation(), diag::note_previous_definition); 679 680 return New->setInvalidDecl(); 681 } 682 683 // If the old declaration is invalid, just give up here. 684 if (Old->isInvalidDecl()) 685 return New->setInvalidDecl(); 686 687 // Determine the "old" type we'll use for checking and diagnostics. 688 QualType OldType; 689 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 690 OldType = OldTypedef->getUnderlyingType(); 691 else 692 OldType = Context.getTypeDeclType(Old); 693 694 // If the typedef types are not identical, reject them in all languages and 695 // with any extensions enabled. 696 697 if (OldType != New->getUnderlyingType() && 698 Context.getCanonicalType(OldType) != 699 Context.getCanonicalType(New->getUnderlyingType())) { 700 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 701 << New->getUnderlyingType() << OldType; 702 if (Old->getLocation().isValid()) 703 Diag(Old->getLocation(), diag::note_previous_definition); 704 return New->setInvalidDecl(); 705 } 706 707 if (getLangOptions().Microsoft) 708 return; 709 710 // C++ [dcl.typedef]p2: 711 // In a given non-class scope, a typedef specifier can be used to 712 // redefine the name of any type declared in that scope to refer 713 // to the type to which it already refers. 714 if (getLangOptions().CPlusPlus) { 715 if (!isa<CXXRecordDecl>(CurContext)) 716 return; 717 Diag(New->getLocation(), diag::err_redefinition) 718 << New->getDeclName(); 719 Diag(Old->getLocation(), diag::note_previous_definition); 720 return New->setInvalidDecl(); 721 } 722 723 // If we have a redefinition of a typedef in C, emit a warning. This warning 724 // is normally mapped to an error, but can be controlled with 725 // -Wtypedef-redefinition. If either the original or the redefinition is 726 // in a system header, don't emit this for compatibility with GCC. 727 if (PP.getDiagnostics().getSuppressSystemWarnings() && 728 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 729 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 730 return; 731 732 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 733 << New->getDeclName(); 734 Diag(Old->getLocation(), diag::note_previous_definition); 735 return; 736} 737 738/// DeclhasAttr - returns true if decl Declaration already has the target 739/// attribute. 740static bool 741DeclHasAttr(const Decl *decl, const Attr *target) { 742 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 743 if (attr->getKind() == target->getKind()) 744 return true; 745 746 return false; 747} 748 749/// MergeAttributes - append attributes from the Old decl to the New one. 750static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 751 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 752 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 753 Attr *NewAttr = attr->clone(C); 754 NewAttr->setInherited(true); 755 New->addAttr(NewAttr); 756 } 757 } 758} 759 760/// Used in MergeFunctionDecl to keep track of function parameters in 761/// C. 762struct GNUCompatibleParamWarning { 763 ParmVarDecl *OldParm; 764 ParmVarDecl *NewParm; 765 QualType PromotedType; 766}; 767 768 769/// getSpecialMember - get the special member enum for a method. 770static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 771 const CXXMethodDecl *MD) { 772 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 773 if (Ctor->isDefaultConstructor()) 774 return Sema::CXXDefaultConstructor; 775 if (Ctor->isCopyConstructor(Ctx)) 776 return Sema::CXXCopyConstructor; 777 } 778 779 if (isa<CXXDestructorDecl>(MD)) 780 return Sema::CXXDestructor; 781 782 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 783 return Sema::CXXCopyAssignment; 784} 785 786/// MergeFunctionDecl - We just parsed a function 'New' from 787/// declarator D which has the same name and scope as a previous 788/// declaration 'Old'. Figure out how to resolve this situation, 789/// merging decls or emitting diagnostics as appropriate. 790/// 791/// In C++, New and Old must be declarations that are not 792/// overloaded. Use IsOverload to determine whether New and Old are 793/// overloaded, and to select the Old declaration that New should be 794/// merged with. 795/// 796/// Returns true if there was an error, false otherwise. 797bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 798 // Verify the old decl was also a function. 799 FunctionDecl *Old = 0; 800 if (FunctionTemplateDecl *OldFunctionTemplate 801 = dyn_cast<FunctionTemplateDecl>(OldD)) 802 Old = OldFunctionTemplate->getTemplatedDecl(); 803 else 804 Old = dyn_cast<FunctionDecl>(OldD); 805 if (!Old) { 806 Diag(New->getLocation(), diag::err_redefinition_different_kind) 807 << New->getDeclName(); 808 Diag(OldD->getLocation(), diag::note_previous_definition); 809 return true; 810 } 811 812 // Determine whether the previous declaration was a definition, 813 // implicit declaration, or a declaration. 814 diag::kind PrevDiag; 815 if (Old->isThisDeclarationADefinition()) 816 PrevDiag = diag::note_previous_definition; 817 else if (Old->isImplicit()) 818 PrevDiag = diag::note_previous_implicit_declaration; 819 else 820 PrevDiag = diag::note_previous_declaration; 821 822 QualType OldQType = Context.getCanonicalType(Old->getType()); 823 QualType NewQType = Context.getCanonicalType(New->getType()); 824 825 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 826 New->getStorageClass() == FunctionDecl::Static && 827 Old->getStorageClass() != FunctionDecl::Static) { 828 Diag(New->getLocation(), diag::err_static_non_static) 829 << New; 830 Diag(Old->getLocation(), PrevDiag); 831 return true; 832 } 833 834 if (getLangOptions().CPlusPlus) { 835 // (C++98 13.1p2): 836 // Certain function declarations cannot be overloaded: 837 // -- Function declarations that differ only in the return type 838 // cannot be overloaded. 839 QualType OldReturnType 840 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 841 QualType NewReturnType 842 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 843 if (OldReturnType != NewReturnType) { 844 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 845 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 846 return true; 847 } 848 849 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 850 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 851 if (OldMethod && NewMethod) { 852 if (!NewMethod->getFriendObjectKind() && 853 NewMethod->getLexicalDeclContext()->isRecord()) { 854 // -- Member function declarations with the same name and the 855 // same parameter types cannot be overloaded if any of them 856 // is a static member function declaration. 857 if (OldMethod->isStatic() || NewMethod->isStatic()) { 858 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 859 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 860 return true; 861 } 862 863 // C++ [class.mem]p1: 864 // [...] A member shall not be declared twice in the 865 // member-specification, except that a nested class or member 866 // class template can be declared and then later defined. 867 unsigned NewDiag; 868 if (isa<CXXConstructorDecl>(OldMethod)) 869 NewDiag = diag::err_constructor_redeclared; 870 else if (isa<CXXDestructorDecl>(NewMethod)) 871 NewDiag = diag::err_destructor_redeclared; 872 else if (isa<CXXConversionDecl>(NewMethod)) 873 NewDiag = diag::err_conv_function_redeclared; 874 else 875 NewDiag = diag::err_member_redeclared; 876 877 Diag(New->getLocation(), NewDiag); 878 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 879 } else { 880 if (OldMethod->isImplicit()) { 881 Diag(NewMethod->getLocation(), 882 diag::err_definition_of_implicitly_declared_member) 883 << New << getSpecialMember(Context, OldMethod); 884 885 Diag(OldMethod->getLocation(), 886 diag::note_previous_implicit_declaration); 887 return true; 888 } 889 } 890 } 891 892 // (C++98 8.3.5p3): 893 // All declarations for a function shall agree exactly in both the 894 // return type and the parameter-type-list. 895 if (OldQType == NewQType) 896 return MergeCompatibleFunctionDecls(New, Old); 897 898 // Fall through for conflicting redeclarations and redefinitions. 899 } 900 901 // C: Function types need to be compatible, not identical. This handles 902 // duplicate function decls like "void f(int); void f(enum X);" properly. 903 if (!getLangOptions().CPlusPlus && 904 Context.typesAreCompatible(OldQType, NewQType)) { 905 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 906 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 907 const FunctionProtoType *OldProto = 0; 908 if (isa<FunctionNoProtoType>(NewFuncType) && 909 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 910 // The old declaration provided a function prototype, but the 911 // new declaration does not. Merge in the prototype. 912 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 913 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 914 OldProto->arg_type_end()); 915 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 916 ParamTypes.data(), ParamTypes.size(), 917 OldProto->isVariadic(), 918 OldProto->getTypeQuals()); 919 New->setType(NewQType); 920 New->setHasInheritedPrototype(); 921 922 // Synthesize a parameter for each argument type. 923 llvm::SmallVector<ParmVarDecl*, 16> Params; 924 for (FunctionProtoType::arg_type_iterator 925 ParamType = OldProto->arg_type_begin(), 926 ParamEnd = OldProto->arg_type_end(); 927 ParamType != ParamEnd; ++ParamType) { 928 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 929 SourceLocation(), 0, 930 *ParamType, /*TInfo=*/0, 931 VarDecl::None, 0); 932 Param->setImplicit(); 933 Params.push_back(Param); 934 } 935 936 New->setParams(Context, Params.data(), Params.size()); 937 } 938 939 return MergeCompatibleFunctionDecls(New, Old); 940 } 941 942 // GNU C permits a K&R definition to follow a prototype declaration 943 // if the declared types of the parameters in the K&R definition 944 // match the types in the prototype declaration, even when the 945 // promoted types of the parameters from the K&R definition differ 946 // from the types in the prototype. GCC then keeps the types from 947 // the prototype. 948 // 949 // If a variadic prototype is followed by a non-variadic K&R definition, 950 // the K&R definition becomes variadic. This is sort of an edge case, but 951 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 952 // C99 6.9.1p8. 953 if (!getLangOptions().CPlusPlus && 954 Old->hasPrototype() && !New->hasPrototype() && 955 New->getType()->getAs<FunctionProtoType>() && 956 Old->getNumParams() == New->getNumParams()) { 957 llvm::SmallVector<QualType, 16> ArgTypes; 958 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 959 const FunctionProtoType *OldProto 960 = Old->getType()->getAs<FunctionProtoType>(); 961 const FunctionProtoType *NewProto 962 = New->getType()->getAs<FunctionProtoType>(); 963 964 // Determine whether this is the GNU C extension. 965 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 966 NewProto->getResultType()); 967 bool LooseCompatible = !MergedReturn.isNull(); 968 for (unsigned Idx = 0, End = Old->getNumParams(); 969 LooseCompatible && Idx != End; ++Idx) { 970 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 971 ParmVarDecl *NewParm = New->getParamDecl(Idx); 972 if (Context.typesAreCompatible(OldParm->getType(), 973 NewProto->getArgType(Idx))) { 974 ArgTypes.push_back(NewParm->getType()); 975 } else if (Context.typesAreCompatible(OldParm->getType(), 976 NewParm->getType())) { 977 GNUCompatibleParamWarning Warn 978 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 979 Warnings.push_back(Warn); 980 ArgTypes.push_back(NewParm->getType()); 981 } else 982 LooseCompatible = false; 983 } 984 985 if (LooseCompatible) { 986 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 987 Diag(Warnings[Warn].NewParm->getLocation(), 988 diag::ext_param_promoted_not_compatible_with_prototype) 989 << Warnings[Warn].PromotedType 990 << Warnings[Warn].OldParm->getType(); 991 Diag(Warnings[Warn].OldParm->getLocation(), 992 diag::note_previous_declaration); 993 } 994 995 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 996 ArgTypes.size(), 997 OldProto->isVariadic(), 0)); 998 return MergeCompatibleFunctionDecls(New, Old); 999 } 1000 1001 // Fall through to diagnose conflicting types. 1002 } 1003 1004 // A function that has already been declared has been redeclared or defined 1005 // with a different type- show appropriate diagnostic 1006 if (unsigned BuiltinID = Old->getBuiltinID()) { 1007 // The user has declared a builtin function with an incompatible 1008 // signature. 1009 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1010 // The function the user is redeclaring is a library-defined 1011 // function like 'malloc' or 'printf'. Warn about the 1012 // redeclaration, then pretend that we don't know about this 1013 // library built-in. 1014 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1015 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1016 << Old << Old->getType(); 1017 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1018 Old->setInvalidDecl(); 1019 return false; 1020 } 1021 1022 PrevDiag = diag::note_previous_builtin_declaration; 1023 } 1024 1025 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1026 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1027 return true; 1028} 1029 1030/// \brief Completes the merge of two function declarations that are 1031/// known to be compatible. 1032/// 1033/// This routine handles the merging of attributes and other 1034/// properties of function declarations form the old declaration to 1035/// the new declaration, once we know that New is in fact a 1036/// redeclaration of Old. 1037/// 1038/// \returns false 1039bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1040 // Merge the attributes 1041 MergeAttributes(New, Old, Context); 1042 1043 // Merge the storage class. 1044 if (Old->getStorageClass() != FunctionDecl::Extern && 1045 Old->getStorageClass() != FunctionDecl::None) 1046 New->setStorageClass(Old->getStorageClass()); 1047 1048 // Merge "pure" flag. 1049 if (Old->isPure()) 1050 New->setPure(); 1051 1052 // Merge the "deleted" flag. 1053 if (Old->isDeleted()) 1054 New->setDeleted(); 1055 1056 if (getLangOptions().CPlusPlus) 1057 return MergeCXXFunctionDecl(New, Old); 1058 1059 return false; 1060} 1061 1062/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1063/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1064/// situation, merging decls or emitting diagnostics as appropriate. 1065/// 1066/// Tentative definition rules (C99 6.9.2p2) are checked by 1067/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1068/// definitions here, since the initializer hasn't been attached. 1069/// 1070void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1071 // If the new decl is already invalid, don't do any other checking. 1072 if (New->isInvalidDecl()) 1073 return; 1074 1075 // Verify the old decl was also a variable. 1076 VarDecl *Old = 0; 1077 if (!Previous.isSingleResult() || 1078 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1079 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1080 << New->getDeclName(); 1081 Diag(Previous.getRepresentativeDecl()->getLocation(), 1082 diag::note_previous_definition); 1083 return New->setInvalidDecl(); 1084 } 1085 1086 MergeAttributes(New, Old, Context); 1087 1088 // Merge the types 1089 QualType MergedT; 1090 if (getLangOptions().CPlusPlus) { 1091 if (Context.hasSameType(New->getType(), Old->getType())) 1092 MergedT = New->getType(); 1093 // C++ [basic.link]p10: 1094 // [...] the types specified by all declarations referring to a given 1095 // object or function shall be identical, except that declarations for an 1096 // array object can specify array types that differ by the presence or 1097 // absence of a major array bound (8.3.4). 1098 else if (Old->getType()->isIncompleteArrayType() && 1099 New->getType()->isArrayType()) { 1100 CanQual<ArrayType> OldArray 1101 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1102 CanQual<ArrayType> NewArray 1103 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1104 if (OldArray->getElementType() == NewArray->getElementType()) 1105 MergedT = New->getType(); 1106 } else if (Old->getType()->isArrayType() && 1107 New->getType()->isIncompleteArrayType()) { 1108 CanQual<ArrayType> OldArray 1109 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1110 CanQual<ArrayType> NewArray 1111 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1112 if (OldArray->getElementType() == NewArray->getElementType()) 1113 MergedT = Old->getType(); 1114 } 1115 } else { 1116 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1117 } 1118 if (MergedT.isNull()) { 1119 Diag(New->getLocation(), diag::err_redefinition_different_type) 1120 << New->getDeclName(); 1121 Diag(Old->getLocation(), diag::note_previous_definition); 1122 return New->setInvalidDecl(); 1123 } 1124 New->setType(MergedT); 1125 1126 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1127 if (New->getStorageClass() == VarDecl::Static && 1128 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1129 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1130 Diag(Old->getLocation(), diag::note_previous_definition); 1131 return New->setInvalidDecl(); 1132 } 1133 // C99 6.2.2p4: 1134 // For an identifier declared with the storage-class specifier 1135 // extern in a scope in which a prior declaration of that 1136 // identifier is visible,23) if the prior declaration specifies 1137 // internal or external linkage, the linkage of the identifier at 1138 // the later declaration is the same as the linkage specified at 1139 // the prior declaration. If no prior declaration is visible, or 1140 // if the prior declaration specifies no linkage, then the 1141 // identifier has external linkage. 1142 if (New->hasExternalStorage() && Old->hasLinkage()) 1143 /* Okay */; 1144 else if (New->getStorageClass() != VarDecl::Static && 1145 Old->getStorageClass() == VarDecl::Static) { 1146 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1147 Diag(Old->getLocation(), diag::note_previous_definition); 1148 return New->setInvalidDecl(); 1149 } 1150 1151 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1152 1153 // FIXME: The test for external storage here seems wrong? We still 1154 // need to check for mismatches. 1155 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1156 // Don't complain about out-of-line definitions of static members. 1157 !(Old->getLexicalDeclContext()->isRecord() && 1158 !New->getLexicalDeclContext()->isRecord())) { 1159 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1160 Diag(Old->getLocation(), diag::note_previous_definition); 1161 return New->setInvalidDecl(); 1162 } 1163 1164 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1165 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1166 Diag(Old->getLocation(), diag::note_previous_definition); 1167 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1168 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1169 Diag(Old->getLocation(), diag::note_previous_definition); 1170 } 1171 1172 // Keep a chain of previous declarations. 1173 New->setPreviousDeclaration(Old); 1174} 1175 1176/// CheckFallThrough - Check that we don't fall off the end of a 1177/// Statement that should return a value. 1178/// 1179/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1180/// MaybeFallThrough iff we might or might not fall off the end, 1181/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1182/// return. We assume NeverFallThrough iff we never fall off the end of the 1183/// statement but we may return. We assume that functions not marked noreturn 1184/// will return. 1185Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1186 // FIXME: Eventually share this CFG object when we have other warnings based 1187 // of the CFG. This can be done using AnalysisContext. 1188 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1189 1190 // FIXME: They should never return 0, fix that, delete this code. 1191 if (cfg == 0) 1192 // FIXME: This should be NeverFallThrough 1193 return NeverFallThroughOrReturn; 1194 // The CFG leaves in dead things, and we don't want to dead code paths to 1195 // confuse us, so we mark all live things first. 1196 std::queue<CFGBlock*> workq; 1197 llvm::BitVector live(cfg->getNumBlockIDs()); 1198 // Prep work queue 1199 workq.push(&cfg->getEntry()); 1200 // Solve 1201 while (!workq.empty()) { 1202 CFGBlock *item = workq.front(); 1203 workq.pop(); 1204 live.set(item->getBlockID()); 1205 for (CFGBlock::succ_iterator I=item->succ_begin(), 1206 E=item->succ_end(); 1207 I != E; 1208 ++I) { 1209 if ((*I) && !live[(*I)->getBlockID()]) { 1210 live.set((*I)->getBlockID()); 1211 workq.push(*I); 1212 } 1213 } 1214 } 1215 1216 // Now we know what is live, we check the live precessors of the exit block 1217 // and look for fall through paths, being careful to ignore normal returns, 1218 // and exceptional paths. 1219 bool HasLiveReturn = false; 1220 bool HasFakeEdge = false; 1221 bool HasPlainEdge = false; 1222 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1223 E = cfg->getExit().pred_end(); 1224 I != E; 1225 ++I) { 1226 CFGBlock& B = **I; 1227 if (!live[B.getBlockID()]) 1228 continue; 1229 if (B.size() == 0) { 1230 // A labeled empty statement, or the entry block... 1231 HasPlainEdge = true; 1232 continue; 1233 } 1234 Stmt *S = B[B.size()-1]; 1235 if (isa<ReturnStmt>(S)) { 1236 HasLiveReturn = true; 1237 continue; 1238 } 1239 if (isa<ObjCAtThrowStmt>(S)) { 1240 HasFakeEdge = true; 1241 continue; 1242 } 1243 if (isa<CXXThrowExpr>(S)) { 1244 HasFakeEdge = true; 1245 continue; 1246 } 1247 bool NoReturnEdge = false; 1248 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1249 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1250 if (CEE->getType().getNoReturnAttr()) { 1251 NoReturnEdge = true; 1252 HasFakeEdge = true; 1253 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1254 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1255 if (FD->hasAttr<NoReturnAttr>()) { 1256 NoReturnEdge = true; 1257 HasFakeEdge = true; 1258 } 1259 } 1260 } 1261 } 1262 // FIXME: Add noreturn message sends. 1263 if (NoReturnEdge == false) 1264 HasPlainEdge = true; 1265 } 1266 if (!HasPlainEdge) { 1267 if (HasLiveReturn) 1268 return NeverFallThrough; 1269 return NeverFallThroughOrReturn; 1270 } 1271 if (HasFakeEdge || HasLiveReturn) 1272 return MaybeFallThrough; 1273 // This says AlwaysFallThrough for calls to functions that are not marked 1274 // noreturn, that don't return. If people would like this warning to be more 1275 // accurate, such functions should be marked as noreturn. 1276 return AlwaysFallThrough; 1277} 1278 1279/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1280/// function that should return a value. Check that we don't fall off the end 1281/// of a noreturn function. We assume that functions and blocks not marked 1282/// noreturn will return. 1283void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1284 // FIXME: Would be nice if we had a better way to control cascading errors, 1285 // but for now, avoid them. The problem is that when Parse sees: 1286 // int foo() { return a; } 1287 // The return is eaten and the Sema code sees just: 1288 // int foo() { } 1289 // which this code would then warn about. 1290 if (getDiagnostics().hasErrorOccurred()) 1291 return; 1292 1293 bool ReturnsVoid = false; 1294 bool HasNoReturn = false; 1295 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1296 // If the result type of the function is a dependent type, we don't know 1297 // whether it will be void or not, so don't 1298 if (FD->getResultType()->isDependentType()) 1299 return; 1300 if (FD->getResultType()->isVoidType()) 1301 ReturnsVoid = true; 1302 if (FD->hasAttr<NoReturnAttr>()) 1303 HasNoReturn = true; 1304 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1305 if (MD->getResultType()->isVoidType()) 1306 ReturnsVoid = true; 1307 if (MD->hasAttr<NoReturnAttr>()) 1308 HasNoReturn = true; 1309 } 1310 1311 // Short circuit for compilation speed. 1312 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1313 == Diagnostic::Ignored || ReturnsVoid) 1314 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1315 == Diagnostic::Ignored || !HasNoReturn) 1316 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1317 == Diagnostic::Ignored || !ReturnsVoid)) 1318 return; 1319 // FIXME: Function try block 1320 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1321 switch (CheckFallThrough(Body)) { 1322 case MaybeFallThrough: 1323 if (HasNoReturn) 1324 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1325 else if (!ReturnsVoid) 1326 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1327 break; 1328 case AlwaysFallThrough: 1329 if (HasNoReturn) 1330 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1331 else if (!ReturnsVoid) 1332 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1333 break; 1334 case NeverFallThroughOrReturn: 1335 if (ReturnsVoid && !HasNoReturn) 1336 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1337 break; 1338 case NeverFallThrough: 1339 break; 1340 } 1341 } 1342} 1343 1344/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1345/// that should return a value. Check that we don't fall off the end of a 1346/// noreturn block. We assume that functions and blocks not marked noreturn 1347/// will return. 1348void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1349 // FIXME: Would be nice if we had a better way to control cascading errors, 1350 // but for now, avoid them. The problem is that when Parse sees: 1351 // int foo() { return a; } 1352 // The return is eaten and the Sema code sees just: 1353 // int foo() { } 1354 // which this code would then warn about. 1355 if (getDiagnostics().hasErrorOccurred()) 1356 return; 1357 bool ReturnsVoid = false; 1358 bool HasNoReturn = false; 1359 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1360 if (FT->getResultType()->isVoidType()) 1361 ReturnsVoid = true; 1362 if (FT->getNoReturnAttr()) 1363 HasNoReturn = true; 1364 } 1365 1366 // Short circuit for compilation speed. 1367 if (ReturnsVoid 1368 && !HasNoReturn 1369 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1370 == Diagnostic::Ignored || !ReturnsVoid)) 1371 return; 1372 // FIXME: Funtion try block 1373 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1374 switch (CheckFallThrough(Body)) { 1375 case MaybeFallThrough: 1376 if (HasNoReturn) 1377 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1378 else if (!ReturnsVoid) 1379 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1380 break; 1381 case AlwaysFallThrough: 1382 if (HasNoReturn) 1383 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1384 else if (!ReturnsVoid) 1385 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1386 break; 1387 case NeverFallThroughOrReturn: 1388 if (ReturnsVoid) 1389 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1390 break; 1391 case NeverFallThrough: 1392 break; 1393 } 1394 } 1395} 1396 1397/// CheckParmsForFunctionDef - Check that the parameters of the given 1398/// function are appropriate for the definition of a function. This 1399/// takes care of any checks that cannot be performed on the 1400/// declaration itself, e.g., that the types of each of the function 1401/// parameters are complete. 1402bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1403 bool HasInvalidParm = false; 1404 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1405 ParmVarDecl *Param = FD->getParamDecl(p); 1406 1407 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1408 // function declarator that is part of a function definition of 1409 // that function shall not have incomplete type. 1410 // 1411 // This is also C++ [dcl.fct]p6. 1412 if (!Param->isInvalidDecl() && 1413 RequireCompleteType(Param->getLocation(), Param->getType(), 1414 diag::err_typecheck_decl_incomplete_type)) { 1415 Param->setInvalidDecl(); 1416 HasInvalidParm = true; 1417 } 1418 1419 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1420 // declaration of each parameter shall include an identifier. 1421 if (Param->getIdentifier() == 0 && 1422 !Param->isImplicit() && 1423 !getLangOptions().CPlusPlus) 1424 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1425 } 1426 1427 return HasInvalidParm; 1428} 1429 1430/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1431/// no declarator (e.g. "struct foo;") is parsed. 1432Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1433 // FIXME: Error on auto/register at file scope 1434 // FIXME: Error on inline/virtual/explicit 1435 // FIXME: Error on invalid restrict 1436 // FIXME: Warn on useless __thread 1437 // FIXME: Warn on useless const/volatile 1438 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1439 // FIXME: Warn on useless attributes 1440 Decl *TagD = 0; 1441 TagDecl *Tag = 0; 1442 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1443 DS.getTypeSpecType() == DeclSpec::TST_struct || 1444 DS.getTypeSpecType() == DeclSpec::TST_union || 1445 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1446 TagD = static_cast<Decl *>(DS.getTypeRep()); 1447 1448 if (!TagD) // We probably had an error 1449 return DeclPtrTy(); 1450 1451 // Note that the above type specs guarantee that the 1452 // type rep is a Decl, whereas in many of the others 1453 // it's a Type. 1454 Tag = dyn_cast<TagDecl>(TagD); 1455 } 1456 1457 if (DS.isFriendSpecified()) { 1458 // If we're dealing with a class template decl, assume that the 1459 // template routines are handling it. 1460 if (TagD && isa<ClassTemplateDecl>(TagD)) 1461 return DeclPtrTy(); 1462 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1463 } 1464 1465 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1466 // If there are attributes in the DeclSpec, apply them to the record. 1467 if (const AttributeList *AL = DS.getAttributes()) 1468 ProcessDeclAttributeList(S, Record, AL); 1469 1470 if (!Record->getDeclName() && Record->isDefinition() && 1471 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1472 if (getLangOptions().CPlusPlus || 1473 Record->getDeclContext()->isRecord()) 1474 return BuildAnonymousStructOrUnion(S, DS, Record); 1475 1476 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1477 << DS.getSourceRange(); 1478 } 1479 1480 // Microsoft allows unnamed struct/union fields. Don't complain 1481 // about them. 1482 // FIXME: Should we support Microsoft's extensions in this area? 1483 if (Record->getDeclName() && getLangOptions().Microsoft) 1484 return DeclPtrTy::make(Tag); 1485 } 1486 1487 if (!DS.isMissingDeclaratorOk() && 1488 DS.getTypeSpecType() != DeclSpec::TST_error) { 1489 // Warn about typedefs of enums without names, since this is an 1490 // extension in both Microsoft an GNU. 1491 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1492 Tag && isa<EnumDecl>(Tag)) { 1493 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1494 << DS.getSourceRange(); 1495 return DeclPtrTy::make(Tag); 1496 } 1497 1498 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1499 << DS.getSourceRange(); 1500 return DeclPtrTy(); 1501 } 1502 1503 return DeclPtrTy::make(Tag); 1504} 1505 1506/// We are trying to introduce the given name into the given context; 1507/// check if there's an existing declaration that can't be overloaded. 1508/// 1509/// \return true if this is a forbidden redeclaration 1510bool Sema::CheckRedeclaration(DeclContext *DC, 1511 DeclarationName Name, 1512 SourceLocation NameLoc, 1513 unsigned diagnostic) { 1514 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName, 1515 ForRedeclaration); 1516 LookupQualifiedName(R, DC); 1517 1518 if (R.empty()) return false; 1519 1520 if (R.getResultKind() == LookupResult::Found && 1521 isa<TagDecl>(R.getFoundDecl())) 1522 return false; 1523 1524 // Pick a representative declaration. 1525 NamedDecl *PrevDecl = (*R.begin())->getUnderlyingDecl(); 1526 1527 Diag(NameLoc, diagnostic) << Name; 1528 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1529 1530 return true; 1531} 1532 1533/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1534/// anonymous struct or union AnonRecord into the owning context Owner 1535/// and scope S. This routine will be invoked just after we realize 1536/// that an unnamed union or struct is actually an anonymous union or 1537/// struct, e.g., 1538/// 1539/// @code 1540/// union { 1541/// int i; 1542/// float f; 1543/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1544/// // f into the surrounding scope.x 1545/// @endcode 1546/// 1547/// This routine is recursive, injecting the names of nested anonymous 1548/// structs/unions into the owning context and scope as well. 1549bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1550 RecordDecl *AnonRecord) { 1551 unsigned diagKind 1552 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1553 : diag::err_anonymous_struct_member_redecl; 1554 1555 bool Invalid = false; 1556 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1557 FEnd = AnonRecord->field_end(); 1558 F != FEnd; ++F) { 1559 if ((*F)->getDeclName()) { 1560 if (CheckRedeclaration(Owner, (*F)->getDeclName(), 1561 (*F)->getLocation(), diagKind)) { 1562 // C++ [class.union]p2: 1563 // The names of the members of an anonymous union shall be 1564 // distinct from the names of any other entity in the 1565 // scope in which the anonymous union is declared. 1566 Invalid = true; 1567 } else { 1568 // C++ [class.union]p2: 1569 // For the purpose of name lookup, after the anonymous union 1570 // definition, the members of the anonymous union are 1571 // considered to have been defined in the scope in which the 1572 // anonymous union is declared. 1573 Owner->makeDeclVisibleInContext(*F); 1574 S->AddDecl(DeclPtrTy::make(*F)); 1575 IdResolver.AddDecl(*F); 1576 } 1577 } else if (const RecordType *InnerRecordType 1578 = (*F)->getType()->getAs<RecordType>()) { 1579 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1580 if (InnerRecord->isAnonymousStructOrUnion()) 1581 Invalid = Invalid || 1582 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1583 } 1584 } 1585 1586 return Invalid; 1587} 1588 1589/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1590/// anonymous structure or union. Anonymous unions are a C++ feature 1591/// (C++ [class.union]) and a GNU C extension; anonymous structures 1592/// are a GNU C and GNU C++ extension. 1593Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1594 RecordDecl *Record) { 1595 DeclContext *Owner = Record->getDeclContext(); 1596 1597 // Diagnose whether this anonymous struct/union is an extension. 1598 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1599 Diag(Record->getLocation(), diag::ext_anonymous_union); 1600 else if (!Record->isUnion()) 1601 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1602 1603 // C and C++ require different kinds of checks for anonymous 1604 // structs/unions. 1605 bool Invalid = false; 1606 if (getLangOptions().CPlusPlus) { 1607 const char* PrevSpec = 0; 1608 unsigned DiagID; 1609 // C++ [class.union]p3: 1610 // Anonymous unions declared in a named namespace or in the 1611 // global namespace shall be declared static. 1612 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1613 (isa<TranslationUnitDecl>(Owner) || 1614 (isa<NamespaceDecl>(Owner) && 1615 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1616 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1617 Invalid = true; 1618 1619 // Recover by adding 'static'. 1620 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1621 PrevSpec, DiagID); 1622 } 1623 // C++ [class.union]p3: 1624 // A storage class is not allowed in a declaration of an 1625 // anonymous union in a class scope. 1626 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1627 isa<RecordDecl>(Owner)) { 1628 Diag(DS.getStorageClassSpecLoc(), 1629 diag::err_anonymous_union_with_storage_spec); 1630 Invalid = true; 1631 1632 // Recover by removing the storage specifier. 1633 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1634 PrevSpec, DiagID); 1635 } 1636 1637 // C++ [class.union]p2: 1638 // The member-specification of an anonymous union shall only 1639 // define non-static data members. [Note: nested types and 1640 // functions cannot be declared within an anonymous union. ] 1641 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1642 MemEnd = Record->decls_end(); 1643 Mem != MemEnd; ++Mem) { 1644 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1645 // C++ [class.union]p3: 1646 // An anonymous union shall not have private or protected 1647 // members (clause 11). 1648 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1649 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1650 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1651 Invalid = true; 1652 } 1653 } else if ((*Mem)->isImplicit()) { 1654 // Any implicit members are fine. 1655 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1656 // This is a type that showed up in an 1657 // elaborated-type-specifier inside the anonymous struct or 1658 // union, but which actually declares a type outside of the 1659 // anonymous struct or union. It's okay. 1660 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1661 if (!MemRecord->isAnonymousStructOrUnion() && 1662 MemRecord->getDeclName()) { 1663 // This is a nested type declaration. 1664 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1665 << (int)Record->isUnion(); 1666 Invalid = true; 1667 } 1668 } else { 1669 // We have something that isn't a non-static data 1670 // member. Complain about it. 1671 unsigned DK = diag::err_anonymous_record_bad_member; 1672 if (isa<TypeDecl>(*Mem)) 1673 DK = diag::err_anonymous_record_with_type; 1674 else if (isa<FunctionDecl>(*Mem)) 1675 DK = diag::err_anonymous_record_with_function; 1676 else if (isa<VarDecl>(*Mem)) 1677 DK = diag::err_anonymous_record_with_static; 1678 Diag((*Mem)->getLocation(), DK) 1679 << (int)Record->isUnion(); 1680 Invalid = true; 1681 } 1682 } 1683 } 1684 1685 if (!Record->isUnion() && !Owner->isRecord()) { 1686 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1687 << (int)getLangOptions().CPlusPlus; 1688 Invalid = true; 1689 } 1690 1691 // Mock up a declarator. 1692 Declarator Dc(DS, Declarator::TypeNameContext); 1693 TypeSourceInfo *TInfo = 0; 1694 GetTypeForDeclarator(Dc, S, &TInfo); 1695 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1696 1697 // Create a declaration for this anonymous struct/union. 1698 NamedDecl *Anon = 0; 1699 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1700 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1701 /*IdentifierInfo=*/0, 1702 Context.getTypeDeclType(Record), 1703 TInfo, 1704 /*BitWidth=*/0, /*Mutable=*/false); 1705 Anon->setAccess(AS_public); 1706 if (getLangOptions().CPlusPlus) 1707 FieldCollector->Add(cast<FieldDecl>(Anon)); 1708 } else { 1709 VarDecl::StorageClass SC; 1710 switch (DS.getStorageClassSpec()) { 1711 default: assert(0 && "Unknown storage class!"); 1712 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1713 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1714 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1715 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1716 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1717 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1718 case DeclSpec::SCS_mutable: 1719 // mutable can only appear on non-static class members, so it's always 1720 // an error here 1721 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1722 Invalid = true; 1723 SC = VarDecl::None; 1724 break; 1725 } 1726 1727 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1728 /*IdentifierInfo=*/0, 1729 Context.getTypeDeclType(Record), 1730 TInfo, 1731 SC); 1732 } 1733 Anon->setImplicit(); 1734 1735 // Add the anonymous struct/union object to the current 1736 // context. We'll be referencing this object when we refer to one of 1737 // its members. 1738 Owner->addDecl(Anon); 1739 1740 // Inject the members of the anonymous struct/union into the owning 1741 // context and into the identifier resolver chain for name lookup 1742 // purposes. 1743 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1744 Invalid = true; 1745 1746 // Mark this as an anonymous struct/union type. Note that we do not 1747 // do this until after we have already checked and injected the 1748 // members of this anonymous struct/union type, because otherwise 1749 // the members could be injected twice: once by DeclContext when it 1750 // builds its lookup table, and once by 1751 // InjectAnonymousStructOrUnionMembers. 1752 Record->setAnonymousStructOrUnion(true); 1753 1754 if (Invalid) 1755 Anon->setInvalidDecl(); 1756 1757 return DeclPtrTy::make(Anon); 1758} 1759 1760 1761/// GetNameForDeclarator - Determine the full declaration name for the 1762/// given Declarator. 1763DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1764 return GetNameFromUnqualifiedId(D.getName()); 1765} 1766 1767/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1768DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1769 switch (Name.getKind()) { 1770 case UnqualifiedId::IK_Identifier: 1771 return DeclarationName(Name.Identifier); 1772 1773 case UnqualifiedId::IK_OperatorFunctionId: 1774 return Context.DeclarationNames.getCXXOperatorName( 1775 Name.OperatorFunctionId.Operator); 1776 1777 case UnqualifiedId::IK_LiteralOperatorId: 1778 return Context.DeclarationNames.getCXXLiteralOperatorName( 1779 Name.Identifier); 1780 1781 case UnqualifiedId::IK_ConversionFunctionId: { 1782 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1783 if (Ty.isNull()) 1784 return DeclarationName(); 1785 1786 return Context.DeclarationNames.getCXXConversionFunctionName( 1787 Context.getCanonicalType(Ty)); 1788 } 1789 1790 case UnqualifiedId::IK_ConstructorName: { 1791 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1792 if (Ty.isNull()) 1793 return DeclarationName(); 1794 1795 return Context.DeclarationNames.getCXXConstructorName( 1796 Context.getCanonicalType(Ty)); 1797 } 1798 1799 case UnqualifiedId::IK_DestructorName: { 1800 QualType Ty = GetTypeFromParser(Name.DestructorName); 1801 if (Ty.isNull()) 1802 return DeclarationName(); 1803 1804 return Context.DeclarationNames.getCXXDestructorName( 1805 Context.getCanonicalType(Ty)); 1806 } 1807 1808 case UnqualifiedId::IK_TemplateId: { 1809 TemplateName TName 1810 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1811 return Context.getNameForTemplate(TName); 1812 } 1813 } 1814 1815 assert(false && "Unknown name kind"); 1816 return DeclarationName(); 1817} 1818 1819/// isNearlyMatchingFunction - Determine whether the C++ functions 1820/// Declaration and Definition are "nearly" matching. This heuristic 1821/// is used to improve diagnostics in the case where an out-of-line 1822/// function definition doesn't match any declaration within 1823/// the class or namespace. 1824static bool isNearlyMatchingFunction(ASTContext &Context, 1825 FunctionDecl *Declaration, 1826 FunctionDecl *Definition) { 1827 if (Declaration->param_size() != Definition->param_size()) 1828 return false; 1829 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1830 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1831 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1832 1833 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1834 DefParamTy.getNonReferenceType())) 1835 return false; 1836 } 1837 1838 return true; 1839} 1840 1841Sema::DeclPtrTy 1842Sema::HandleDeclarator(Scope *S, Declarator &D, 1843 MultiTemplateParamsArg TemplateParamLists, 1844 bool IsFunctionDefinition) { 1845 DeclarationName Name = GetNameForDeclarator(D); 1846 1847 // All of these full declarators require an identifier. If it doesn't have 1848 // one, the ParsedFreeStandingDeclSpec action should be used. 1849 if (!Name) { 1850 if (!D.isInvalidType()) // Reject this if we think it is valid. 1851 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1852 diag::err_declarator_need_ident) 1853 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1854 return DeclPtrTy(); 1855 } 1856 1857 // The scope passed in may not be a decl scope. Zip up the scope tree until 1858 // we find one that is. 1859 while ((S->getFlags() & Scope::DeclScope) == 0 || 1860 (S->getFlags() & Scope::TemplateParamScope) != 0) 1861 S = S->getParent(); 1862 1863 // If this is an out-of-line definition of a member of a class template 1864 // or class template partial specialization, we may need to rebuild the 1865 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1866 // for more information. 1867 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1868 // handle expressions properly. 1869 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1870 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1871 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1872 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1873 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1874 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1875 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1876 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1877 // FIXME: Preserve type source info. 1878 QualType T = GetTypeFromParser(DS.getTypeRep()); 1879 EnterDeclaratorContext(S, DC); 1880 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1881 ExitDeclaratorContext(S); 1882 if (T.isNull()) 1883 return DeclPtrTy(); 1884 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1885 } 1886 } 1887 1888 DeclContext *DC; 1889 NamedDecl *New; 1890 1891 TypeSourceInfo *TInfo = 0; 1892 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1893 1894 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1895 ForRedeclaration); 1896 1897 // See if this is a redefinition of a variable in the same scope. 1898 if (D.getCXXScopeSpec().isInvalid()) { 1899 DC = CurContext; 1900 D.setInvalidType(); 1901 } else if (!D.getCXXScopeSpec().isSet()) { 1902 bool IsLinkageLookup = false; 1903 1904 // If the declaration we're planning to build will be a function 1905 // or object with linkage, then look for another declaration with 1906 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1907 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1908 /* Do nothing*/; 1909 else if (R->isFunctionType()) { 1910 if (CurContext->isFunctionOrMethod() || 1911 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1912 IsLinkageLookup = true; 1913 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1914 IsLinkageLookup = true; 1915 else if (CurContext->getLookupContext()->isTranslationUnit() && 1916 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1917 IsLinkageLookup = true; 1918 1919 if (IsLinkageLookup) 1920 Previous.clear(LookupRedeclarationWithLinkage); 1921 1922 DC = CurContext; 1923 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1924 } else { // Something like "int foo::x;" 1925 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1926 1927 if (!DC) { 1928 // If we could not compute the declaration context, it's because the 1929 // declaration context is dependent but does not refer to a class, 1930 // class template, or class template partial specialization. Complain 1931 // and return early, to avoid the coming semantic disaster. 1932 Diag(D.getIdentifierLoc(), 1933 diag::err_template_qualified_declarator_no_match) 1934 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1935 << D.getCXXScopeSpec().getRange(); 1936 return DeclPtrTy(); 1937 } 1938 1939 if (!DC->isDependentContext() && 1940 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1941 return DeclPtrTy(); 1942 1943 LookupQualifiedName(Previous, DC); 1944 1945 // Don't consider using declarations as previous declarations for 1946 // out-of-line members. 1947 RemoveUsingDecls(Previous); 1948 1949 // C++ 7.3.1.2p2: 1950 // Members (including explicit specializations of templates) of a named 1951 // namespace can also be defined outside that namespace by explicit 1952 // qualification of the name being defined, provided that the entity being 1953 // defined was already declared in the namespace and the definition appears 1954 // after the point of declaration in a namespace that encloses the 1955 // declarations namespace. 1956 // 1957 // Note that we only check the context at this point. We don't yet 1958 // have enough information to make sure that PrevDecl is actually 1959 // the declaration we want to match. For example, given: 1960 // 1961 // class X { 1962 // void f(); 1963 // void f(float); 1964 // }; 1965 // 1966 // void X::f(int) { } // ill-formed 1967 // 1968 // In this case, PrevDecl will point to the overload set 1969 // containing the two f's declared in X, but neither of them 1970 // matches. 1971 1972 // First check whether we named the global scope. 1973 if (isa<TranslationUnitDecl>(DC)) { 1974 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1975 << Name << D.getCXXScopeSpec().getRange(); 1976 } else { 1977 DeclContext *Cur = CurContext; 1978 while (isa<LinkageSpecDecl>(Cur)) 1979 Cur = Cur->getParent(); 1980 if (!Cur->Encloses(DC)) { 1981 // The qualifying scope doesn't enclose the original declaration. 1982 // Emit diagnostic based on current scope. 1983 SourceLocation L = D.getIdentifierLoc(); 1984 SourceRange R = D.getCXXScopeSpec().getRange(); 1985 if (isa<FunctionDecl>(Cur)) 1986 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1987 else 1988 Diag(L, diag::err_invalid_declarator_scope) 1989 << Name << cast<NamedDecl>(DC) << R; 1990 D.setInvalidType(); 1991 } 1992 } 1993 } 1994 1995 if (Previous.isSingleResult() && 1996 Previous.getFoundDecl()->isTemplateParameter()) { 1997 // Maybe we will complain about the shadowed template parameter. 1998 if (!D.isInvalidType()) 1999 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2000 Previous.getFoundDecl())) 2001 D.setInvalidType(); 2002 2003 // Just pretend that we didn't see the previous declaration. 2004 Previous.clear(); 2005 } 2006 2007 // In C++, the previous declaration we find might be a tag type 2008 // (class or enum). In this case, the new declaration will hide the 2009 // tag type. Note that this does does not apply if we're declaring a 2010 // typedef (C++ [dcl.typedef]p4). 2011 if (Previous.isSingleTagDecl() && 2012 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2013 Previous.clear(); 2014 2015 bool Redeclaration = false; 2016 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2017 if (TemplateParamLists.size()) { 2018 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2019 return DeclPtrTy(); 2020 } 2021 2022 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2023 } else if (R->isFunctionType()) { 2024 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2025 move(TemplateParamLists), 2026 IsFunctionDefinition, Redeclaration); 2027 } else { 2028 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2029 move(TemplateParamLists), 2030 Redeclaration); 2031 } 2032 2033 if (New == 0) 2034 return DeclPtrTy(); 2035 2036 // If this has an identifier and is not an invalid redeclaration or 2037 // function template specialization, add it to the scope stack. 2038 if (Name && !(Redeclaration && New->isInvalidDecl())) 2039 PushOnScopeChains(New, S); 2040 2041 return DeclPtrTy::make(New); 2042} 2043 2044/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2045/// types into constant array types in certain situations which would otherwise 2046/// be errors (for GCC compatibility). 2047static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2048 ASTContext &Context, 2049 bool &SizeIsNegative) { 2050 // This method tries to turn a variable array into a constant 2051 // array even when the size isn't an ICE. This is necessary 2052 // for compatibility with code that depends on gcc's buggy 2053 // constant expression folding, like struct {char x[(int)(char*)2];} 2054 SizeIsNegative = false; 2055 2056 QualifierCollector Qs; 2057 const Type *Ty = Qs.strip(T); 2058 2059 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2060 QualType Pointee = PTy->getPointeeType(); 2061 QualType FixedType = 2062 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2063 if (FixedType.isNull()) return FixedType; 2064 FixedType = Context.getPointerType(FixedType); 2065 return Qs.apply(FixedType); 2066 } 2067 2068 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2069 if (!VLATy) 2070 return QualType(); 2071 // FIXME: We should probably handle this case 2072 if (VLATy->getElementType()->isVariablyModifiedType()) 2073 return QualType(); 2074 2075 Expr::EvalResult EvalResult; 2076 if (!VLATy->getSizeExpr() || 2077 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2078 !EvalResult.Val.isInt()) 2079 return QualType(); 2080 2081 llvm::APSInt &Res = EvalResult.Val.getInt(); 2082 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2083 // TODO: preserve the size expression in declarator info 2084 return Context.getConstantArrayType(VLATy->getElementType(), 2085 Res, ArrayType::Normal, 0); 2086 } 2087 2088 SizeIsNegative = true; 2089 return QualType(); 2090} 2091 2092/// \brief Register the given locally-scoped external C declaration so 2093/// that it can be found later for redeclarations 2094void 2095Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2096 const LookupResult &Previous, 2097 Scope *S) { 2098 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2099 "Decl is not a locally-scoped decl!"); 2100 // Note that we have a locally-scoped external with this name. 2101 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2102 2103 if (!Previous.isSingleResult()) 2104 return; 2105 2106 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2107 2108 // If there was a previous declaration of this variable, it may be 2109 // in our identifier chain. Update the identifier chain with the new 2110 // declaration. 2111 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2112 // The previous declaration was found on the identifer resolver 2113 // chain, so remove it from its scope. 2114 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2115 S = S->getParent(); 2116 2117 if (S) 2118 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2119 } 2120} 2121 2122/// \brief Diagnose function specifiers on a declaration of an identifier that 2123/// does not identify a function. 2124void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2125 // FIXME: We should probably indicate the identifier in question to avoid 2126 // confusion for constructs like "inline int a(), b;" 2127 if (D.getDeclSpec().isInlineSpecified()) 2128 Diag(D.getDeclSpec().getInlineSpecLoc(), 2129 diag::err_inline_non_function); 2130 2131 if (D.getDeclSpec().isVirtualSpecified()) 2132 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2133 diag::err_virtual_non_function); 2134 2135 if (D.getDeclSpec().isExplicitSpecified()) 2136 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2137 diag::err_explicit_non_function); 2138} 2139 2140NamedDecl* 2141Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2142 QualType R, TypeSourceInfo *TInfo, 2143 LookupResult &Previous, bool &Redeclaration) { 2144 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2145 if (D.getCXXScopeSpec().isSet()) { 2146 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2147 << D.getCXXScopeSpec().getRange(); 2148 D.setInvalidType(); 2149 // Pretend we didn't see the scope specifier. 2150 DC = 0; 2151 } 2152 2153 if (getLangOptions().CPlusPlus) { 2154 // Check that there are no default arguments (C++ only). 2155 CheckExtraCXXDefaultArguments(D); 2156 } 2157 2158 DiagnoseFunctionSpecifiers(D); 2159 2160 if (D.getDeclSpec().isThreadSpecified()) 2161 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2162 2163 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2164 if (!NewTD) return 0; 2165 2166 // Handle attributes prior to checking for duplicates in MergeVarDecl 2167 ProcessDeclAttributes(S, NewTD, D); 2168 2169 // Merge the decl with the existing one if appropriate. If the decl is 2170 // in an outer scope, it isn't the same thing. 2171 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2172 if (!Previous.empty()) { 2173 Redeclaration = true; 2174 MergeTypeDefDecl(NewTD, Previous); 2175 } 2176 2177 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2178 // then it shall have block scope. 2179 QualType T = NewTD->getUnderlyingType(); 2180 if (T->isVariablyModifiedType()) { 2181 CurFunctionNeedsScopeChecking = true; 2182 2183 if (S->getFnParent() == 0) { 2184 bool SizeIsNegative; 2185 QualType FixedTy = 2186 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2187 if (!FixedTy.isNull()) { 2188 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2189 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2190 } else { 2191 if (SizeIsNegative) 2192 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2193 else if (T->isVariableArrayType()) 2194 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2195 else 2196 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2197 NewTD->setInvalidDecl(); 2198 } 2199 } 2200 } 2201 2202 // If this is the C FILE type, notify the AST context. 2203 if (IdentifierInfo *II = NewTD->getIdentifier()) 2204 if (!NewTD->isInvalidDecl() && 2205 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2206 if (II->isStr("FILE")) 2207 Context.setFILEDecl(NewTD); 2208 else if (II->isStr("jmp_buf")) 2209 Context.setjmp_bufDecl(NewTD); 2210 else if (II->isStr("sigjmp_buf")) 2211 Context.setsigjmp_bufDecl(NewTD); 2212 } 2213 2214 return NewTD; 2215} 2216 2217/// \brief Determines whether the given declaration is an out-of-scope 2218/// previous declaration. 2219/// 2220/// This routine should be invoked when name lookup has found a 2221/// previous declaration (PrevDecl) that is not in the scope where a 2222/// new declaration by the same name is being introduced. If the new 2223/// declaration occurs in a local scope, previous declarations with 2224/// linkage may still be considered previous declarations (C99 2225/// 6.2.2p4-5, C++ [basic.link]p6). 2226/// 2227/// \param PrevDecl the previous declaration found by name 2228/// lookup 2229/// 2230/// \param DC the context in which the new declaration is being 2231/// declared. 2232/// 2233/// \returns true if PrevDecl is an out-of-scope previous declaration 2234/// for a new delcaration with the same name. 2235static bool 2236isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2237 ASTContext &Context) { 2238 if (!PrevDecl) 2239 return 0; 2240 2241 if (!PrevDecl->hasLinkage()) 2242 return false; 2243 2244 if (Context.getLangOptions().CPlusPlus) { 2245 // C++ [basic.link]p6: 2246 // If there is a visible declaration of an entity with linkage 2247 // having the same name and type, ignoring entities declared 2248 // outside the innermost enclosing namespace scope, the block 2249 // scope declaration declares that same entity and receives the 2250 // linkage of the previous declaration. 2251 DeclContext *OuterContext = DC->getLookupContext(); 2252 if (!OuterContext->isFunctionOrMethod()) 2253 // This rule only applies to block-scope declarations. 2254 return false; 2255 else { 2256 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2257 if (PrevOuterContext->isRecord()) 2258 // We found a member function: ignore it. 2259 return false; 2260 else { 2261 // Find the innermost enclosing namespace for the new and 2262 // previous declarations. 2263 while (!OuterContext->isFileContext()) 2264 OuterContext = OuterContext->getParent(); 2265 while (!PrevOuterContext->isFileContext()) 2266 PrevOuterContext = PrevOuterContext->getParent(); 2267 2268 // The previous declaration is in a different namespace, so it 2269 // isn't the same function. 2270 if (OuterContext->getPrimaryContext() != 2271 PrevOuterContext->getPrimaryContext()) 2272 return false; 2273 } 2274 } 2275 } 2276 2277 return true; 2278} 2279 2280NamedDecl* 2281Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2282 QualType R, TypeSourceInfo *TInfo, 2283 LookupResult &Previous, 2284 MultiTemplateParamsArg TemplateParamLists, 2285 bool &Redeclaration) { 2286 DeclarationName Name = GetNameForDeclarator(D); 2287 2288 // Check that there are no default arguments (C++ only). 2289 if (getLangOptions().CPlusPlus) 2290 CheckExtraCXXDefaultArguments(D); 2291 2292 VarDecl *NewVD; 2293 VarDecl::StorageClass SC; 2294 switch (D.getDeclSpec().getStorageClassSpec()) { 2295 default: assert(0 && "Unknown storage class!"); 2296 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2297 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2298 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2299 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2300 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2301 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2302 case DeclSpec::SCS_mutable: 2303 // mutable can only appear on non-static class members, so it's always 2304 // an error here 2305 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2306 D.setInvalidType(); 2307 SC = VarDecl::None; 2308 break; 2309 } 2310 2311 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2312 if (!II) { 2313 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2314 << Name.getAsString(); 2315 return 0; 2316 } 2317 2318 DiagnoseFunctionSpecifiers(D); 2319 2320 if (!DC->isRecord() && S->getFnParent() == 0) { 2321 // C99 6.9p2: The storage-class specifiers auto and register shall not 2322 // appear in the declaration specifiers in an external declaration. 2323 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2324 2325 // If this is a register variable with an asm label specified, then this 2326 // is a GNU extension. 2327 if (SC == VarDecl::Register && D.getAsmLabel()) 2328 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2329 else 2330 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2331 D.setInvalidType(); 2332 } 2333 } 2334 if (DC->isRecord() && !CurContext->isRecord()) { 2335 // This is an out-of-line definition of a static data member. 2336 if (SC == VarDecl::Static) { 2337 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2338 diag::err_static_out_of_line) 2339 << CodeModificationHint::CreateRemoval( 2340 D.getDeclSpec().getStorageClassSpecLoc()); 2341 } else if (SC == VarDecl::None) 2342 SC = VarDecl::Static; 2343 } 2344 if (SC == VarDecl::Static) { 2345 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2346 if (RD->isLocalClass()) 2347 Diag(D.getIdentifierLoc(), 2348 diag::err_static_data_member_not_allowed_in_local_class) 2349 << Name << RD->getDeclName(); 2350 } 2351 } 2352 2353 // Match up the template parameter lists with the scope specifier, then 2354 // determine whether we have a template or a template specialization. 2355 bool isExplicitSpecialization = false; 2356 if (TemplateParameterList *TemplateParams 2357 = MatchTemplateParametersToScopeSpecifier( 2358 D.getDeclSpec().getSourceRange().getBegin(), 2359 D.getCXXScopeSpec(), 2360 (TemplateParameterList**)TemplateParamLists.get(), 2361 TemplateParamLists.size(), 2362 isExplicitSpecialization)) { 2363 if (TemplateParams->size() > 0) { 2364 // There is no such thing as a variable template. 2365 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2366 << II 2367 << SourceRange(TemplateParams->getTemplateLoc(), 2368 TemplateParams->getRAngleLoc()); 2369 return 0; 2370 } else { 2371 // There is an extraneous 'template<>' for this variable. Complain 2372 // about it, but allow the declaration of the variable. 2373 Diag(TemplateParams->getTemplateLoc(), 2374 diag::err_template_variable_noparams) 2375 << II 2376 << SourceRange(TemplateParams->getTemplateLoc(), 2377 TemplateParams->getRAngleLoc()); 2378 2379 isExplicitSpecialization = true; 2380 } 2381 } 2382 2383 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2384 II, R, TInfo, SC); 2385 2386 if (D.isInvalidType()) 2387 NewVD->setInvalidDecl(); 2388 2389 if (D.getDeclSpec().isThreadSpecified()) { 2390 if (NewVD->hasLocalStorage()) 2391 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2392 else if (!Context.Target.isTLSSupported()) 2393 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2394 else 2395 NewVD->setThreadSpecified(true); 2396 } 2397 2398 // Set the lexical context. If the declarator has a C++ scope specifier, the 2399 // lexical context will be different from the semantic context. 2400 NewVD->setLexicalDeclContext(CurContext); 2401 2402 // Handle attributes prior to checking for duplicates in MergeVarDecl 2403 ProcessDeclAttributes(S, NewVD, D); 2404 2405 // Handle GNU asm-label extension (encoded as an attribute). 2406 if (Expr *E = (Expr*) D.getAsmLabel()) { 2407 // The parser guarantees this is a string. 2408 StringLiteral *SE = cast<StringLiteral>(E); 2409 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2410 } 2411 2412 // Don't consider existing declarations that are in a different 2413 // scope and are out-of-semantic-context declarations (if the new 2414 // declaration has linkage). 2415 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2416 2417 // Merge the decl with the existing one if appropriate. 2418 if (!Previous.empty()) { 2419 if (Previous.isSingleResult() && 2420 isa<FieldDecl>(Previous.getFoundDecl()) && 2421 D.getCXXScopeSpec().isSet()) { 2422 // The user tried to define a non-static data member 2423 // out-of-line (C++ [dcl.meaning]p1). 2424 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2425 << D.getCXXScopeSpec().getRange(); 2426 Previous.clear(); 2427 NewVD->setInvalidDecl(); 2428 } 2429 } else if (D.getCXXScopeSpec().isSet()) { 2430 // No previous declaration in the qualifying scope. 2431 Diag(D.getIdentifierLoc(), diag::err_no_member) 2432 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2433 << D.getCXXScopeSpec().getRange(); 2434 NewVD->setInvalidDecl(); 2435 } 2436 2437 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2438 2439 // This is an explicit specialization of a static data member. Check it. 2440 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2441 CheckMemberSpecialization(NewVD, Previous)) 2442 NewVD->setInvalidDecl(); 2443 2444 // attributes declared post-definition are currently ignored 2445 if (Previous.isSingleResult()) { 2446 const VarDecl *Def = 0; 2447 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2448 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2449 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2450 Diag(Def->getLocation(), diag::note_previous_definition); 2451 } 2452 } 2453 2454 // If this is a locally-scoped extern C variable, update the map of 2455 // such variables. 2456 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2457 !NewVD->isInvalidDecl()) 2458 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2459 2460 return NewVD; 2461} 2462 2463/// \brief Perform semantic checking on a newly-created variable 2464/// declaration. 2465/// 2466/// This routine performs all of the type-checking required for a 2467/// variable declaration once it has been built. It is used both to 2468/// check variables after they have been parsed and their declarators 2469/// have been translated into a declaration, and to check variables 2470/// that have been instantiated from a template. 2471/// 2472/// Sets NewVD->isInvalidDecl() if an error was encountered. 2473void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2474 LookupResult &Previous, 2475 bool &Redeclaration) { 2476 // If the decl is already known invalid, don't check it. 2477 if (NewVD->isInvalidDecl()) 2478 return; 2479 2480 QualType T = NewVD->getType(); 2481 2482 if (T->isObjCInterfaceType()) { 2483 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2484 return NewVD->setInvalidDecl(); 2485 } 2486 2487 // Emit an error if an address space was applied to decl with local storage. 2488 // This includes arrays of objects with address space qualifiers, but not 2489 // automatic variables that point to other address spaces. 2490 // ISO/IEC TR 18037 S5.1.2 2491 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2492 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2493 return NewVD->setInvalidDecl(); 2494 } 2495 2496 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2497 && !NewVD->hasAttr<BlocksAttr>()) 2498 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2499 2500 bool isVM = T->isVariablyModifiedType(); 2501 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2502 NewVD->hasAttr<BlocksAttr>()) 2503 CurFunctionNeedsScopeChecking = true; 2504 2505 if ((isVM && NewVD->hasLinkage()) || 2506 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2507 bool SizeIsNegative; 2508 QualType FixedTy = 2509 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2510 2511 if (FixedTy.isNull() && T->isVariableArrayType()) { 2512 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2513 // FIXME: This won't give the correct result for 2514 // int a[10][n]; 2515 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2516 2517 if (NewVD->isFileVarDecl()) 2518 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2519 << SizeRange; 2520 else if (NewVD->getStorageClass() == VarDecl::Static) 2521 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2522 << SizeRange; 2523 else 2524 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2525 << SizeRange; 2526 return NewVD->setInvalidDecl(); 2527 } 2528 2529 if (FixedTy.isNull()) { 2530 if (NewVD->isFileVarDecl()) 2531 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2532 else 2533 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2534 return NewVD->setInvalidDecl(); 2535 } 2536 2537 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2538 NewVD->setType(FixedTy); 2539 } 2540 2541 if (Previous.empty() && NewVD->isExternC()) { 2542 // Since we did not find anything by this name and we're declaring 2543 // an extern "C" variable, look for a non-visible extern "C" 2544 // declaration with the same name. 2545 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2546 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2547 if (Pos != LocallyScopedExternalDecls.end()) 2548 Previous.addDecl(Pos->second); 2549 } 2550 2551 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2552 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2553 << T; 2554 return NewVD->setInvalidDecl(); 2555 } 2556 2557 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2558 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2559 return NewVD->setInvalidDecl(); 2560 } 2561 2562 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2563 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2564 return NewVD->setInvalidDecl(); 2565 } 2566 2567 if (!Previous.empty()) { 2568 Redeclaration = true; 2569 MergeVarDecl(NewVD, Previous); 2570 } 2571} 2572 2573/// \brief Data used with FindOverriddenMethod 2574struct FindOverriddenMethodData { 2575 Sema *S; 2576 CXXMethodDecl *Method; 2577}; 2578 2579/// \brief Member lookup function that determines whether a given C++ 2580/// method overrides a method in a base class, to be used with 2581/// CXXRecordDecl::lookupInBases(). 2582static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2583 CXXBasePath &Path, 2584 void *UserData) { 2585 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2586 2587 FindOverriddenMethodData *Data 2588 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2589 2590 DeclarationName Name = Data->Method->getDeclName(); 2591 2592 // FIXME: Do we care about other names here too? 2593 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2594 // We really want to find the base class constructor here. 2595 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2596 CanQualType CT = Data->S->Context.getCanonicalType(T); 2597 2598 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2599 } 2600 2601 for (Path.Decls = BaseRecord->lookup(Name); 2602 Path.Decls.first != Path.Decls.second; 2603 ++Path.Decls.first) { 2604 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2605 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2606 return true; 2607 } 2608 } 2609 2610 return false; 2611} 2612 2613/// AddOverriddenMethods - See if a method overrides any in the base classes, 2614/// and if so, check that it's a valid override and remember it. 2615void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2616 // Look for virtual methods in base classes that this method might override. 2617 CXXBasePaths Paths; 2618 FindOverriddenMethodData Data; 2619 Data.Method = MD; 2620 Data.S = this; 2621 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2622 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2623 E = Paths.found_decls_end(); I != E; ++I) { 2624 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2625 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2626 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2627 !CheckOverridingFunctionAttributes(MD, OldMD)) 2628 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2629 } 2630 } 2631 } 2632} 2633 2634NamedDecl* 2635Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2636 QualType R, TypeSourceInfo *TInfo, 2637 LookupResult &Previous, 2638 MultiTemplateParamsArg TemplateParamLists, 2639 bool IsFunctionDefinition, bool &Redeclaration) { 2640 assert(R.getTypePtr()->isFunctionType()); 2641 2642 DeclarationName Name = GetNameForDeclarator(D); 2643 FunctionDecl::StorageClass SC = FunctionDecl::None; 2644 switch (D.getDeclSpec().getStorageClassSpec()) { 2645 default: assert(0 && "Unknown storage class!"); 2646 case DeclSpec::SCS_auto: 2647 case DeclSpec::SCS_register: 2648 case DeclSpec::SCS_mutable: 2649 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2650 diag::err_typecheck_sclass_func); 2651 D.setInvalidType(); 2652 break; 2653 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2654 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2655 case DeclSpec::SCS_static: { 2656 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2657 // C99 6.7.1p5: 2658 // The declaration of an identifier for a function that has 2659 // block scope shall have no explicit storage-class specifier 2660 // other than extern 2661 // See also (C++ [dcl.stc]p4). 2662 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2663 diag::err_static_block_func); 2664 SC = FunctionDecl::None; 2665 } else 2666 SC = FunctionDecl::Static; 2667 break; 2668 } 2669 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2670 } 2671 2672 if (D.getDeclSpec().isThreadSpecified()) 2673 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2674 2675 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2676 bool isInline = D.getDeclSpec().isInlineSpecified(); 2677 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2678 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2679 2680 // Check that the return type is not an abstract class type. 2681 // For record types, this is done by the AbstractClassUsageDiagnoser once 2682 // the class has been completely parsed. 2683 if (!DC->isRecord() && 2684 RequireNonAbstractType(D.getIdentifierLoc(), 2685 R->getAs<FunctionType>()->getResultType(), 2686 diag::err_abstract_type_in_decl, 2687 AbstractReturnType)) 2688 D.setInvalidType(); 2689 2690 // Do not allow returning a objc interface by-value. 2691 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2692 Diag(D.getIdentifierLoc(), 2693 diag::err_object_cannot_be_passed_returned_by_value) << 0 2694 << R->getAs<FunctionType>()->getResultType(); 2695 D.setInvalidType(); 2696 } 2697 2698 bool isVirtualOkay = false; 2699 FunctionDecl *NewFD; 2700 2701 if (isFriend) { 2702 // C++ [class.friend]p5 2703 // A function can be defined in a friend declaration of a 2704 // class . . . . Such a function is implicitly inline. 2705 isInline |= IsFunctionDefinition; 2706 } 2707 2708 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2709 // This is a C++ constructor declaration. 2710 assert(DC->isRecord() && 2711 "Constructors can only be declared in a member context"); 2712 2713 R = CheckConstructorDeclarator(D, R, SC); 2714 2715 // Create the new declaration 2716 NewFD = CXXConstructorDecl::Create(Context, 2717 cast<CXXRecordDecl>(DC), 2718 D.getIdentifierLoc(), Name, R, TInfo, 2719 isExplicit, isInline, 2720 /*isImplicitlyDeclared=*/false); 2721 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2722 // This is a C++ destructor declaration. 2723 if (DC->isRecord()) { 2724 R = CheckDestructorDeclarator(D, SC); 2725 2726 NewFD = CXXDestructorDecl::Create(Context, 2727 cast<CXXRecordDecl>(DC), 2728 D.getIdentifierLoc(), Name, R, 2729 isInline, 2730 /*isImplicitlyDeclared=*/false); 2731 2732 isVirtualOkay = true; 2733 } else { 2734 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2735 2736 // Create a FunctionDecl to satisfy the function definition parsing 2737 // code path. 2738 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2739 Name, R, TInfo, SC, isInline, 2740 /*hasPrototype=*/true); 2741 D.setInvalidType(); 2742 } 2743 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2744 if (!DC->isRecord()) { 2745 Diag(D.getIdentifierLoc(), 2746 diag::err_conv_function_not_member); 2747 return 0; 2748 } 2749 2750 CheckConversionDeclarator(D, R, SC); 2751 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2752 D.getIdentifierLoc(), Name, R, TInfo, 2753 isInline, isExplicit); 2754 2755 isVirtualOkay = true; 2756 } else if (DC->isRecord()) { 2757 // If the of the function is the same as the name of the record, then this 2758 // must be an invalid constructor that has a return type. 2759 // (The parser checks for a return type and makes the declarator a 2760 // constructor if it has no return type). 2761 // must have an invalid constructor that has a return type 2762 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2763 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2764 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2765 << SourceRange(D.getIdentifierLoc()); 2766 return 0; 2767 } 2768 2769 bool isStatic = SC == FunctionDecl::Static; 2770 2771 // [class.free]p1: 2772 // Any allocation function for a class T is a static member 2773 // (even if not explicitly declared static). 2774 if (Name.getCXXOverloadedOperator() == OO_New || 2775 Name.getCXXOverloadedOperator() == OO_Array_New) 2776 isStatic = true; 2777 2778 // [class.free]p6 Any deallocation function for a class X is a static member 2779 // (even if not explicitly declared static). 2780 if (Name.getCXXOverloadedOperator() == OO_Delete || 2781 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2782 isStatic = true; 2783 2784 // This is a C++ method declaration. 2785 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2786 D.getIdentifierLoc(), Name, R, TInfo, 2787 isStatic, isInline); 2788 2789 isVirtualOkay = !isStatic; 2790 } else { 2791 // Determine whether the function was written with a 2792 // prototype. This true when: 2793 // - we're in C++ (where every function has a prototype), 2794 // - there is a prototype in the declarator, or 2795 // - the type R of the function is some kind of typedef or other reference 2796 // to a type name (which eventually refers to a function type). 2797 bool HasPrototype = 2798 getLangOptions().CPlusPlus || 2799 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2800 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2801 2802 NewFD = FunctionDecl::Create(Context, DC, 2803 D.getIdentifierLoc(), 2804 Name, R, TInfo, SC, isInline, HasPrototype); 2805 } 2806 2807 if (D.isInvalidType()) 2808 NewFD->setInvalidDecl(); 2809 2810 // Set the lexical context. If the declarator has a C++ 2811 // scope specifier, or is the object of a friend declaration, the 2812 // lexical context will be different from the semantic context. 2813 NewFD->setLexicalDeclContext(CurContext); 2814 2815 // Match up the template parameter lists with the scope specifier, then 2816 // determine whether we have a template or a template specialization. 2817 FunctionTemplateDecl *FunctionTemplate = 0; 2818 bool isExplicitSpecialization = false; 2819 bool isFunctionTemplateSpecialization = false; 2820 if (TemplateParameterList *TemplateParams 2821 = MatchTemplateParametersToScopeSpecifier( 2822 D.getDeclSpec().getSourceRange().getBegin(), 2823 D.getCXXScopeSpec(), 2824 (TemplateParameterList**)TemplateParamLists.get(), 2825 TemplateParamLists.size(), 2826 isExplicitSpecialization)) { 2827 if (TemplateParams->size() > 0) { 2828 // This is a function template 2829 2830 // Check that we can declare a template here. 2831 if (CheckTemplateDeclScope(S, TemplateParams)) 2832 return 0; 2833 2834 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2835 NewFD->getLocation(), 2836 Name, TemplateParams, 2837 NewFD); 2838 FunctionTemplate->setLexicalDeclContext(CurContext); 2839 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2840 } else { 2841 // This is a function template specialization. 2842 isFunctionTemplateSpecialization = true; 2843 } 2844 2845 // FIXME: Free this memory properly. 2846 TemplateParamLists.release(); 2847 } 2848 2849 // C++ [dcl.fct.spec]p5: 2850 // The virtual specifier shall only be used in declarations of 2851 // nonstatic class member functions that appear within a 2852 // member-specification of a class declaration; see 10.3. 2853 // 2854 if (isVirtual && !NewFD->isInvalidDecl()) { 2855 if (!isVirtualOkay) { 2856 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2857 diag::err_virtual_non_function); 2858 } else if (!CurContext->isRecord()) { 2859 // 'virtual' was specified outside of the class. 2860 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2861 << CodeModificationHint::CreateRemoval( 2862 D.getDeclSpec().getVirtualSpecLoc()); 2863 } else { 2864 // Okay: Add virtual to the method. 2865 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2866 CurClass->setMethodAsVirtual(NewFD); 2867 } 2868 } 2869 2870 // Filter out previous declarations that don't match the scope. 2871 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2872 2873 if (isFriend) { 2874 // DC is the namespace in which the function is being declared. 2875 assert((DC->isFileContext() || !Previous.empty()) && 2876 "previously-undeclared friend function being created " 2877 "in a non-namespace context"); 2878 2879 if (FunctionTemplate) { 2880 FunctionTemplate->setObjectOfFriendDecl( 2881 /* PreviouslyDeclared= */ !Previous.empty()); 2882 FunctionTemplate->setAccess(AS_public); 2883 } 2884 else 2885 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2886 2887 NewFD->setAccess(AS_public); 2888 } 2889 2890 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2891 !CurContext->isRecord()) { 2892 // C++ [class.static]p1: 2893 // A data or function member of a class may be declared static 2894 // in a class definition, in which case it is a static member of 2895 // the class. 2896 2897 // Complain about the 'static' specifier if it's on an out-of-line 2898 // member function definition. 2899 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2900 diag::err_static_out_of_line) 2901 << CodeModificationHint::CreateRemoval( 2902 D.getDeclSpec().getStorageClassSpecLoc()); 2903 } 2904 2905 // Handle GNU asm-label extension (encoded as an attribute). 2906 if (Expr *E = (Expr*) D.getAsmLabel()) { 2907 // The parser guarantees this is a string. 2908 StringLiteral *SE = cast<StringLiteral>(E); 2909 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2910 } 2911 2912 // Copy the parameter declarations from the declarator D to the function 2913 // declaration NewFD, if they are available. First scavenge them into Params. 2914 llvm::SmallVector<ParmVarDecl*, 16> Params; 2915 if (D.getNumTypeObjects() > 0) { 2916 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2917 2918 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2919 // function that takes no arguments, not a function that takes a 2920 // single void argument. 2921 // We let through "const void" here because Sema::GetTypeForDeclarator 2922 // already checks for that case. 2923 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2924 FTI.ArgInfo[0].Param && 2925 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2926 // Empty arg list, don't push any params. 2927 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2928 2929 // In C++, the empty parameter-type-list must be spelled "void"; a 2930 // typedef of void is not permitted. 2931 if (getLangOptions().CPlusPlus && 2932 Param->getType().getUnqualifiedType() != Context.VoidTy) 2933 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2934 // FIXME: Leaks decl? 2935 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2936 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2937 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2938 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2939 Param->setDeclContext(NewFD); 2940 Params.push_back(Param); 2941 } 2942 } 2943 2944 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2945 // When we're declaring a function with a typedef, typeof, etc as in the 2946 // following example, we'll need to synthesize (unnamed) 2947 // parameters for use in the declaration. 2948 // 2949 // @code 2950 // typedef void fn(int); 2951 // fn f; 2952 // @endcode 2953 2954 // Synthesize a parameter for each argument type. 2955 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2956 AE = FT->arg_type_end(); AI != AE; ++AI) { 2957 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2958 SourceLocation(), 0, 2959 *AI, /*TInfo=*/0, 2960 VarDecl::None, 0); 2961 Param->setImplicit(); 2962 Params.push_back(Param); 2963 } 2964 } else { 2965 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2966 "Should not need args for typedef of non-prototype fn"); 2967 } 2968 // Finally, we know we have the right number of parameters, install them. 2969 NewFD->setParams(Context, Params.data(), Params.size()); 2970 2971 // If the declarator is a template-id, translate the parser's template 2972 // argument list into our AST format. 2973 bool HasExplicitTemplateArgs = false; 2974 TemplateArgumentListInfo TemplateArgs; 2975 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2976 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2977 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 2978 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 2979 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2980 TemplateId->getTemplateArgs(), 2981 TemplateId->NumArgs); 2982 translateTemplateArguments(TemplateArgsPtr, 2983 TemplateArgs); 2984 TemplateArgsPtr.release(); 2985 2986 HasExplicitTemplateArgs = true; 2987 2988 if (FunctionTemplate) { 2989 // FIXME: Diagnose function template with explicit template 2990 // arguments. 2991 HasExplicitTemplateArgs = false; 2992 } else if (!isFunctionTemplateSpecialization && 2993 !D.getDeclSpec().isFriendSpecified()) { 2994 // We have encountered something that the user meant to be a 2995 // specialization (because it has explicitly-specified template 2996 // arguments) but that was not introduced with a "template<>" (or had 2997 // too few of them). 2998 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2999 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3000 << CodeModificationHint::CreateInsertion( 3001 D.getDeclSpec().getSourceRange().getBegin(), 3002 "template<> "); 3003 isFunctionTemplateSpecialization = true; 3004 } 3005 } 3006 3007 if (isFunctionTemplateSpecialization) { 3008 if (CheckFunctionTemplateSpecialization(NewFD, 3009 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3010 Previous)) 3011 NewFD->setInvalidDecl(); 3012 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3013 CheckMemberSpecialization(NewFD, Previous)) 3014 NewFD->setInvalidDecl(); 3015 3016 // Perform semantic checking on the function declaration. 3017 bool OverloadableAttrRequired = false; // FIXME: HACK! 3018 CheckFunctionDeclaration(NewFD, Previous, isExplicitSpecialization, 3019 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3020 3021 assert((NewFD->isInvalidDecl() || !Redeclaration || 3022 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3023 "previous declaration set still overloaded"); 3024 3025 // If we have a function template, check the template parameter 3026 // list. This will check and merge default template arguments. 3027 if (FunctionTemplate) { 3028 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3029 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3030 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3031 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3032 : TPC_FunctionTemplate); 3033 } 3034 3035 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3036 // An out-of-line member function declaration must also be a 3037 // definition (C++ [dcl.meaning]p1). 3038 // Note that this is not the case for explicit specializations of 3039 // function templates or member functions of class templates, per 3040 // C++ [temp.expl.spec]p2. 3041 if (!IsFunctionDefinition && !isFriend && 3042 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3043 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3044 << D.getCXXScopeSpec().getRange(); 3045 NewFD->setInvalidDecl(); 3046 } else if (!Redeclaration) { 3047 // The user tried to provide an out-of-line definition for a 3048 // function that is a member of a class or namespace, but there 3049 // was no such member function declared (C++ [class.mfct]p2, 3050 // C++ [namespace.memdef]p2). For example: 3051 // 3052 // class X { 3053 // void f() const; 3054 // }; 3055 // 3056 // void X::f() { } // ill-formed 3057 // 3058 // Complain about this problem, and attempt to suggest close 3059 // matches (e.g., those that differ only in cv-qualifiers and 3060 // whether the parameter types are references). 3061 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3062 << Name << DC << D.getCXXScopeSpec().getRange(); 3063 NewFD->setInvalidDecl(); 3064 3065 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3066 ForRedeclaration); 3067 LookupQualifiedName(Prev, DC); 3068 assert(!Prev.isAmbiguous() && 3069 "Cannot have an ambiguity in previous-declaration lookup"); 3070 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3071 Func != FuncEnd; ++Func) { 3072 if (isa<FunctionDecl>(*Func) && 3073 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3074 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3075 } 3076 } 3077 } 3078 3079 // Handle attributes. We need to have merged decls when handling attributes 3080 // (for example to check for conflicts, etc). 3081 // FIXME: This needs to happen before we merge declarations. Then, 3082 // let attribute merging cope with attribute conflicts. 3083 ProcessDeclAttributes(S, NewFD, D); 3084 3085 // attributes declared post-definition are currently ignored 3086 if (Redeclaration && Previous.isSingleResult()) { 3087 const FunctionDecl *Def; 3088 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3089 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3090 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3091 Diag(Def->getLocation(), diag::note_previous_definition); 3092 } 3093 } 3094 3095 AddKnownFunctionAttributes(NewFD); 3096 3097 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3098 // If a function name is overloadable in C, then every function 3099 // with that name must be marked "overloadable". 3100 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3101 << Redeclaration << NewFD; 3102 if (!Previous.empty()) 3103 Diag(Previous.getRepresentativeDecl()->getLocation(), 3104 diag::note_attribute_overloadable_prev_overload); 3105 NewFD->addAttr(::new (Context) OverloadableAttr()); 3106 } 3107 3108 // If this is a locally-scoped extern C function, update the 3109 // map of such names. 3110 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3111 && !NewFD->isInvalidDecl()) 3112 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3113 3114 // Set this FunctionDecl's range up to the right paren. 3115 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3116 3117 if (FunctionTemplate && NewFD->isInvalidDecl()) 3118 FunctionTemplate->setInvalidDecl(); 3119 3120 if (FunctionTemplate) 3121 return FunctionTemplate; 3122 3123 return NewFD; 3124} 3125 3126/// \brief Perform semantic checking of a new function declaration. 3127/// 3128/// Performs semantic analysis of the new function declaration 3129/// NewFD. This routine performs all semantic checking that does not 3130/// require the actual declarator involved in the declaration, and is 3131/// used both for the declaration of functions as they are parsed 3132/// (called via ActOnDeclarator) and for the declaration of functions 3133/// that have been instantiated via C++ template instantiation (called 3134/// via InstantiateDecl). 3135/// 3136/// \param IsExplicitSpecialiation whether this new function declaration is 3137/// an explicit specialization of the previous declaration. 3138/// 3139/// This sets NewFD->isInvalidDecl() to true if there was an error. 3140void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, 3141 LookupResult &Previous, 3142 bool IsExplicitSpecialization, 3143 bool &Redeclaration, 3144 bool &OverloadableAttrRequired) { 3145 // If NewFD is already known erroneous, don't do any of this checking. 3146 if (NewFD->isInvalidDecl()) 3147 return; 3148 3149 if (NewFD->getResultType()->isVariablyModifiedType()) { 3150 // Functions returning a variably modified type violate C99 6.7.5.2p2 3151 // because all functions have linkage. 3152 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3153 return NewFD->setInvalidDecl(); 3154 } 3155 3156 if (NewFD->isMain()) 3157 CheckMain(NewFD); 3158 3159 // Check for a previous declaration of this name. 3160 if (Previous.empty() && NewFD->isExternC()) { 3161 // Since we did not find anything by this name and we're declaring 3162 // an extern "C" function, look for a non-visible extern "C" 3163 // declaration with the same name. 3164 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3165 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3166 if (Pos != LocallyScopedExternalDecls.end()) 3167 Previous.addDecl(Pos->second); 3168 } 3169 3170 // Merge or overload the declaration with an existing declaration of 3171 // the same name, if appropriate. 3172 if (!Previous.empty()) { 3173 // Determine whether NewFD is an overload of PrevDecl or 3174 // a declaration that requires merging. If it's an overload, 3175 // there's no more work to do here; we'll just add the new 3176 // function to the scope. 3177 3178 NamedDecl *OldDecl = 0; 3179 if (!AllowOverloadingOfFunction(Previous, Context)) { 3180 Redeclaration = true; 3181 OldDecl = Previous.getFoundDecl(); 3182 } else { 3183 if (!getLangOptions().CPlusPlus) { 3184 OverloadableAttrRequired = true; 3185 3186 // Functions marked "overloadable" must have a prototype (that 3187 // we can't get through declaration merging). 3188 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3189 Diag(NewFD->getLocation(), 3190 diag::err_attribute_overloadable_no_prototype) 3191 << NewFD; 3192 Redeclaration = true; 3193 3194 // Turn this into a variadic function with no parameters. 3195 QualType R = Context.getFunctionType( 3196 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3197 0, 0, true, 0); 3198 NewFD->setType(R); 3199 return NewFD->setInvalidDecl(); 3200 } 3201 } 3202 3203 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3204 case Ovl_Match: 3205 // FIXME: hide or conflict with using shadow decls as appropriate 3206 Redeclaration = !isa<UsingShadowDecl>(OldDecl); 3207 break; 3208 3209 case Ovl_NonFunction: 3210 Redeclaration = true; 3211 break; 3212 3213 case Ovl_Overload: 3214 Redeclaration = false; 3215 break; 3216 } 3217 } 3218 3219 if (Redeclaration) { 3220 // NewFD and OldDecl represent declarations that need to be 3221 // merged. 3222 if (MergeFunctionDecl(NewFD, OldDecl)) 3223 return NewFD->setInvalidDecl(); 3224 3225 Previous.clear(); 3226 Previous.addDecl(OldDecl); 3227 3228 if (FunctionTemplateDecl *OldTemplateDecl 3229 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3230 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3231 FunctionTemplateDecl *NewTemplateDecl 3232 = NewFD->getDescribedFunctionTemplate(); 3233 assert(NewTemplateDecl && "Template/non-template mismatch"); 3234 if (CXXMethodDecl *Method 3235 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3236 Method->setAccess(OldTemplateDecl->getAccess()); 3237 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3238 } 3239 3240 // If this is an explicit specialization of a member that is a function 3241 // template, mark it as a member specialization. 3242 if (IsExplicitSpecialization && 3243 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3244 NewTemplateDecl->setMemberSpecialization(); 3245 assert(OldTemplateDecl->isMemberSpecialization()); 3246 } 3247 } else { 3248 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3249 NewFD->setAccess(OldDecl->getAccess()); 3250 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3251 } 3252 } 3253 } 3254 3255 // Semantic checking for this function declaration (in isolation). 3256 if (getLangOptions().CPlusPlus) { 3257 // C++-specific checks. 3258 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3259 CheckConstructor(Constructor); 3260 } else if (CXXDestructorDecl *Destructor = 3261 dyn_cast<CXXDestructorDecl>(NewFD)) { 3262 CXXRecordDecl *Record = Destructor->getParent(); 3263 QualType ClassType = Context.getTypeDeclType(Record); 3264 3265 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3266 // type is dependent? Both gcc and edg can handle that. 3267 if (!ClassType->isDependentType()) { 3268 DeclarationName Name 3269 = Context.DeclarationNames.getCXXDestructorName( 3270 Context.getCanonicalType(ClassType)); 3271 if (NewFD->getDeclName() != Name) { 3272 Diag(NewFD->getLocation(), diag::err_destructor_name); 3273 return NewFD->setInvalidDecl(); 3274 } 3275 } 3276 3277 Record->setUserDeclaredDestructor(true); 3278 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3279 // user-defined destructor. 3280 Record->setPOD(false); 3281 3282 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3283 // declared destructor. 3284 // FIXME: C++0x: don't do this for "= default" destructors 3285 Record->setHasTrivialDestructor(false); 3286 } else if (CXXConversionDecl *Conversion 3287 = dyn_cast<CXXConversionDecl>(NewFD)) { 3288 ActOnConversionDeclarator(Conversion); 3289 } 3290 3291 // Find any virtual functions that this function overrides. 3292 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3293 if (!Method->isFunctionTemplateSpecialization() && 3294 !Method->getDescribedFunctionTemplate()) 3295 AddOverriddenMethods(Method->getParent(), Method); 3296 } 3297 3298 // Additional checks for the destructor; make sure we do this after we 3299 // figure out whether the destructor is virtual. 3300 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3301 if (!Destructor->getParent()->isDependentType()) 3302 CheckDestructor(Destructor); 3303 3304 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3305 if (NewFD->isOverloadedOperator() && 3306 CheckOverloadedOperatorDeclaration(NewFD)) 3307 return NewFD->setInvalidDecl(); 3308 3309 // In C++, check default arguments now that we have merged decls. Unless 3310 // the lexical context is the class, because in this case this is done 3311 // during delayed parsing anyway. 3312 if (!CurContext->isRecord()) 3313 CheckCXXDefaultArguments(NewFD); 3314 } 3315} 3316 3317void Sema::CheckMain(FunctionDecl* FD) { 3318 // C++ [basic.start.main]p3: A program that declares main to be inline 3319 // or static is ill-formed. 3320 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3321 // shall not appear in a declaration of main. 3322 // static main is not an error under C99, but we should warn about it. 3323 bool isInline = FD->isInlineSpecified(); 3324 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3325 if (isInline || isStatic) { 3326 unsigned diagID = diag::warn_unusual_main_decl; 3327 if (isInline || getLangOptions().CPlusPlus) 3328 diagID = diag::err_unusual_main_decl; 3329 3330 int which = isStatic + (isInline << 1) - 1; 3331 Diag(FD->getLocation(), diagID) << which; 3332 } 3333 3334 QualType T = FD->getType(); 3335 assert(T->isFunctionType() && "function decl is not of function type"); 3336 const FunctionType* FT = T->getAs<FunctionType>(); 3337 3338 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3339 // TODO: add a replacement fixit to turn the return type into 'int'. 3340 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3341 FD->setInvalidDecl(true); 3342 } 3343 3344 // Treat protoless main() as nullary. 3345 if (isa<FunctionNoProtoType>(FT)) return; 3346 3347 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3348 unsigned nparams = FTP->getNumArgs(); 3349 assert(FD->getNumParams() == nparams); 3350 3351 if (nparams > 3) { 3352 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3353 FD->setInvalidDecl(true); 3354 nparams = 3; 3355 } 3356 3357 // FIXME: a lot of the following diagnostics would be improved 3358 // if we had some location information about types. 3359 3360 QualType CharPP = 3361 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3362 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3363 3364 for (unsigned i = 0; i < nparams; ++i) { 3365 QualType AT = FTP->getArgType(i); 3366 3367 bool mismatch = true; 3368 3369 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3370 mismatch = false; 3371 else if (Expected[i] == CharPP) { 3372 // As an extension, the following forms are okay: 3373 // char const ** 3374 // char const * const * 3375 // char * const * 3376 3377 QualifierCollector qs; 3378 const PointerType* PT; 3379 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3380 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3381 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3382 qs.removeConst(); 3383 mismatch = !qs.empty(); 3384 } 3385 } 3386 3387 if (mismatch) { 3388 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3389 // TODO: suggest replacing given type with expected type 3390 FD->setInvalidDecl(true); 3391 } 3392 } 3393 3394 if (nparams == 1 && !FD->isInvalidDecl()) { 3395 Diag(FD->getLocation(), diag::warn_main_one_arg); 3396 } 3397} 3398 3399bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3400 // FIXME: Need strict checking. In C89, we need to check for 3401 // any assignment, increment, decrement, function-calls, or 3402 // commas outside of a sizeof. In C99, it's the same list, 3403 // except that the aforementioned are allowed in unevaluated 3404 // expressions. Everything else falls under the 3405 // "may accept other forms of constant expressions" exception. 3406 // (We never end up here for C++, so the constant expression 3407 // rules there don't matter.) 3408 if (Init->isConstantInitializer(Context)) 3409 return false; 3410 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3411 << Init->getSourceRange(); 3412 return true; 3413} 3414 3415void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3416 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3417} 3418 3419/// AddInitializerToDecl - Adds the initializer Init to the 3420/// declaration dcl. If DirectInit is true, this is C++ direct 3421/// initialization rather than copy initialization. 3422void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3423 Decl *RealDecl = dcl.getAs<Decl>(); 3424 // If there is no declaration, there was an error parsing it. Just ignore 3425 // the initializer. 3426 if (RealDecl == 0) 3427 return; 3428 3429 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3430 // With declarators parsed the way they are, the parser cannot 3431 // distinguish between a normal initializer and a pure-specifier. 3432 // Thus this grotesque test. 3433 IntegerLiteral *IL; 3434 Expr *Init = static_cast<Expr *>(init.get()); 3435 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3436 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3437 CheckPureMethod(Method, Init->getSourceRange()); 3438 else { 3439 Diag(Method->getLocation(), diag::err_member_function_initialization) 3440 << Method->getDeclName() << Init->getSourceRange(); 3441 Method->setInvalidDecl(); 3442 } 3443 return; 3444 } 3445 3446 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3447 if (!VDecl) { 3448 if (getLangOptions().CPlusPlus && 3449 RealDecl->getLexicalDeclContext()->isRecord() && 3450 isa<NamedDecl>(RealDecl)) 3451 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3452 << cast<NamedDecl>(RealDecl)->getDeclName(); 3453 else 3454 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3455 RealDecl->setInvalidDecl(); 3456 return; 3457 } 3458 3459 // A definition must end up with a complete type, which means it must be 3460 // complete with the restriction that an array type might be completed by the 3461 // initializer; note that later code assumes this restriction. 3462 QualType BaseDeclType = VDecl->getType(); 3463 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3464 BaseDeclType = Array->getElementType(); 3465 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3466 diag::err_typecheck_decl_incomplete_type)) { 3467 RealDecl->setInvalidDecl(); 3468 return; 3469 } 3470 3471 // The variable can not have an abstract class type. 3472 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3473 diag::err_abstract_type_in_decl, 3474 AbstractVariableType)) 3475 VDecl->setInvalidDecl(); 3476 3477 const VarDecl *Def = 0; 3478 if (VDecl->getDefinition(Def)) { 3479 Diag(VDecl->getLocation(), diag::err_redefinition) 3480 << VDecl->getDeclName(); 3481 Diag(Def->getLocation(), diag::note_previous_definition); 3482 VDecl->setInvalidDecl(); 3483 return; 3484 } 3485 3486 // Take ownership of the expression, now that we're sure we have somewhere 3487 // to put it. 3488 Expr *Init = init.takeAs<Expr>(); 3489 assert(Init && "missing initializer"); 3490 3491 // Get the decls type and save a reference for later, since 3492 // CheckInitializerTypes may change it. 3493 QualType DclT = VDecl->getType(), SavT = DclT; 3494 if (VDecl->isBlockVarDecl()) { 3495 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3496 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3497 VDecl->setInvalidDecl(); 3498 } else if (!VDecl->isInvalidDecl()) { 3499 if (VDecl->getType()->isReferenceType()) { 3500 InitializedEntity Entity 3501 = InitializedEntity::InitializeVariable(VDecl); 3502 3503 // FIXME: Poor source location information. 3504 InitializationKind Kind 3505 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3506 SourceLocation(), 3507 SourceLocation()) 3508 : InitializationKind::CreateCopy(VDecl->getLocation(), 3509 SourceLocation()); 3510 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3511 if (InitSeq) { 3512 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3513 MultiExprArg(*this, (void**)&Init, 1)); 3514 if (Result.isInvalid()) { 3515 VDecl->setInvalidDecl(); 3516 return; 3517 } 3518 3519 Init = Result.takeAs<Expr>(); 3520 } else { 3521 InitSeq.Diagnose(*this, Entity, Kind, &Init, 1); 3522 VDecl->setInvalidDecl(); 3523 return; 3524 } 3525 3526 } else if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3527 VDecl->getDeclName(), DirectInit)) 3528 VDecl->setInvalidDecl(); 3529 3530 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3531 // Don't check invalid declarations to avoid emitting useless diagnostics. 3532 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3533 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3534 CheckForConstantInitializer(Init, DclT); 3535 } 3536 } 3537 } else if (VDecl->isStaticDataMember() && 3538 VDecl->getLexicalDeclContext()->isRecord()) { 3539 // This is an in-class initialization for a static data member, e.g., 3540 // 3541 // struct S { 3542 // static const int value = 17; 3543 // }; 3544 3545 // Attach the initializer 3546 VDecl->setInit(Context, Init); 3547 3548 // C++ [class.mem]p4: 3549 // A member-declarator can contain a constant-initializer only 3550 // if it declares a static member (9.4) of const integral or 3551 // const enumeration type, see 9.4.2. 3552 QualType T = VDecl->getType(); 3553 if (!T->isDependentType() && 3554 (!Context.getCanonicalType(T).isConstQualified() || 3555 !T->isIntegralType())) { 3556 Diag(VDecl->getLocation(), diag::err_member_initialization) 3557 << VDecl->getDeclName() << Init->getSourceRange(); 3558 VDecl->setInvalidDecl(); 3559 } else { 3560 // C++ [class.static.data]p4: 3561 // If a static data member is of const integral or const 3562 // enumeration type, its declaration in the class definition 3563 // can specify a constant-initializer which shall be an 3564 // integral constant expression (5.19). 3565 if (!Init->isTypeDependent() && 3566 !Init->getType()->isIntegralType()) { 3567 // We have a non-dependent, non-integral or enumeration type. 3568 Diag(Init->getSourceRange().getBegin(), 3569 diag::err_in_class_initializer_non_integral_type) 3570 << Init->getType() << Init->getSourceRange(); 3571 VDecl->setInvalidDecl(); 3572 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3573 // Check whether the expression is a constant expression. 3574 llvm::APSInt Value; 3575 SourceLocation Loc; 3576 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3577 Diag(Loc, diag::err_in_class_initializer_non_constant) 3578 << Init->getSourceRange(); 3579 VDecl->setInvalidDecl(); 3580 } else if (!VDecl->getType()->isDependentType()) 3581 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3582 } 3583 } 3584 } else if (VDecl->isFileVarDecl()) { 3585 if (VDecl->getStorageClass() == VarDecl::Extern) 3586 Diag(VDecl->getLocation(), diag::warn_extern_init); 3587 if (!VDecl->isInvalidDecl()) 3588 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3589 VDecl->getDeclName(), DirectInit)) 3590 VDecl->setInvalidDecl(); 3591 3592 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3593 // Don't check invalid declarations to avoid emitting useless diagnostics. 3594 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3595 // C99 6.7.8p4. All file scoped initializers need to be constant. 3596 CheckForConstantInitializer(Init, DclT); 3597 } 3598 } 3599 // If the type changed, it means we had an incomplete type that was 3600 // completed by the initializer. For example: 3601 // int ary[] = { 1, 3, 5 }; 3602 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3603 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3604 VDecl->setType(DclT); 3605 Init->setType(DclT); 3606 } 3607 3608 Init = MaybeCreateCXXExprWithTemporaries(Init, 3609 /*ShouldDestroyTemporaries=*/true); 3610 // Attach the initializer to the decl. 3611 VDecl->setInit(Context, Init); 3612 3613 // If the previous declaration of VDecl was a tentative definition, 3614 // remove it from the set of tentative definitions. 3615 if (VDecl->getPreviousDeclaration() && 3616 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3617 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3618 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3619 } 3620 3621 return; 3622} 3623 3624void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3625 bool TypeContainsUndeducedAuto) { 3626 Decl *RealDecl = dcl.getAs<Decl>(); 3627 3628 // If there is no declaration, there was an error parsing it. Just ignore it. 3629 if (RealDecl == 0) 3630 return; 3631 3632 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3633 QualType Type = Var->getType(); 3634 3635 // Record tentative definitions. 3636 if (Var->isTentativeDefinition(Context)) { 3637 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3638 InsertPair = 3639 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3640 3641 // Keep the latest definition in the map. If we see 'int i; int i;' we 3642 // want the second one in the map. 3643 InsertPair.first->second = Var; 3644 3645 // However, for the list, we don't care about the order, just make sure 3646 // that there are no dupes for a given declaration name. 3647 if (InsertPair.second) 3648 TentativeDefinitionList.push_back(Var->getDeclName()); 3649 } 3650 3651 // C++ [dcl.init.ref]p3: 3652 // The initializer can be omitted for a reference only in a 3653 // parameter declaration (8.3.5), in the declaration of a 3654 // function return type, in the declaration of a class member 3655 // within its class declaration (9.2), and where the extern 3656 // specifier is explicitly used. 3657 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3658 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3659 << Var->getDeclName() 3660 << SourceRange(Var->getLocation(), Var->getLocation()); 3661 Var->setInvalidDecl(); 3662 return; 3663 } 3664 3665 // C++0x [dcl.spec.auto]p3 3666 if (TypeContainsUndeducedAuto) { 3667 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3668 << Var->getDeclName() << Type; 3669 Var->setInvalidDecl(); 3670 return; 3671 } 3672 3673 // An array without size is an incomplete type, and there are no special 3674 // rules in C++ to make such a definition acceptable. 3675 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3676 !Var->hasExternalStorage()) { 3677 Diag(Var->getLocation(), 3678 diag::err_typecheck_incomplete_array_needs_initializer); 3679 Var->setInvalidDecl(); 3680 return; 3681 } 3682 3683 // C++ [temp.expl.spec]p15: 3684 // An explicit specialization of a static data member of a template is a 3685 // definition if the declaration includes an initializer; otherwise, it 3686 // is a declaration. 3687 if (Var->isStaticDataMember() && 3688 Var->getInstantiatedFromStaticDataMember() && 3689 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3690 return; 3691 3692 // C++ [dcl.init]p9: 3693 // If no initializer is specified for an object, and the object 3694 // is of (possibly cv-qualified) non-POD class type (or array 3695 // thereof), the object shall be default-initialized; if the 3696 // object is of const-qualified type, the underlying class type 3697 // shall have a user-declared default constructor. 3698 // 3699 // FIXME: Diagnose the "user-declared default constructor" bit. 3700 if (getLangOptions().CPlusPlus) { 3701 QualType InitType = Type; 3702 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3703 InitType = Context.getBaseElementType(Array); 3704 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3705 InitType->isRecordType() && !InitType->isDependentType()) { 3706 if (!RequireCompleteType(Var->getLocation(), InitType, 3707 diag::err_invalid_incomplete_type_use)) { 3708 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3709 3710 CXXConstructorDecl *Constructor 3711 = PerformInitializationByConstructor(InitType, 3712 MultiExprArg(*this, 0, 0), 3713 Var->getLocation(), 3714 SourceRange(Var->getLocation(), 3715 Var->getLocation()), 3716 Var->getDeclName(), 3717 InitializationKind::CreateDefault(Var->getLocation()), 3718 ConstructorArgs); 3719 3720 // FIXME: Location info for the variable initialization? 3721 if (!Constructor) 3722 Var->setInvalidDecl(); 3723 else { 3724 // FIXME: Cope with initialization of arrays 3725 if (!Constructor->isTrivial() && 3726 InitializeVarWithConstructor(Var, Constructor, 3727 move_arg(ConstructorArgs))) 3728 Var->setInvalidDecl(); 3729 3730 FinalizeVarWithDestructor(Var, InitType); 3731 } 3732 } else { 3733 Var->setInvalidDecl(); 3734 } 3735 } 3736 3737 // The variable can not have an abstract class type. 3738 if (RequireNonAbstractType(Var->getLocation(), Type, 3739 diag::err_abstract_type_in_decl, 3740 AbstractVariableType)) 3741 Var->setInvalidDecl(); 3742 } 3743 3744#if 0 3745 // FIXME: Temporarily disabled because we are not properly parsing 3746 // linkage specifications on declarations, e.g., 3747 // 3748 // extern "C" const CGPoint CGPointerZero; 3749 // 3750 // C++ [dcl.init]p9: 3751 // 3752 // If no initializer is specified for an object, and the 3753 // object is of (possibly cv-qualified) non-POD class type (or 3754 // array thereof), the object shall be default-initialized; if 3755 // the object is of const-qualified type, the underlying class 3756 // type shall have a user-declared default 3757 // constructor. Otherwise, if no initializer is specified for 3758 // an object, the object and its subobjects, if any, have an 3759 // indeterminate initial value; if the object or any of its 3760 // subobjects are of const-qualified type, the program is 3761 // ill-formed. 3762 // 3763 // This isn't technically an error in C, so we don't diagnose it. 3764 // 3765 // FIXME: Actually perform the POD/user-defined default 3766 // constructor check. 3767 if (getLangOptions().CPlusPlus && 3768 Context.getCanonicalType(Type).isConstQualified() && 3769 !Var->hasExternalStorage()) 3770 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3771 << Var->getName() 3772 << SourceRange(Var->getLocation(), Var->getLocation()); 3773#endif 3774 } 3775} 3776 3777Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3778 DeclPtrTy *Group, 3779 unsigned NumDecls) { 3780 llvm::SmallVector<Decl*, 8> Decls; 3781 3782 if (DS.isTypeSpecOwned()) 3783 Decls.push_back((Decl*)DS.getTypeRep()); 3784 3785 for (unsigned i = 0; i != NumDecls; ++i) 3786 if (Decl *D = Group[i].getAs<Decl>()) 3787 Decls.push_back(D); 3788 3789 // Perform semantic analysis that depends on having fully processed both 3790 // the declarator and initializer. 3791 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3792 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3793 if (!IDecl) 3794 continue; 3795 QualType T = IDecl->getType(); 3796 3797 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3798 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3799 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3800 if (T->isDependentType()) { 3801 // If T is dependent, we should not require a complete type. 3802 // (RequireCompleteType shouldn't be called with dependent types.) 3803 // But we still can at least check if we've got an array of unspecified 3804 // size without an initializer. 3805 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3806 !IDecl->getInit()) { 3807 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3808 << T; 3809 IDecl->setInvalidDecl(); 3810 } 3811 } else if (!IDecl->isInvalidDecl()) { 3812 // If T is an incomplete array type with an initializer list that is 3813 // dependent on something, its size has not been fixed. We could attempt 3814 // to fix the size for such arrays, but we would still have to check 3815 // here for initializers containing a C++0x vararg expansion, e.g. 3816 // template <typename... Args> void f(Args... args) { 3817 // int vals[] = { args }; 3818 // } 3819 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3820 Expr *Init = IDecl->getInit(); 3821 if (IAT && Init && 3822 (Init->isTypeDependent() || Init->isValueDependent())) { 3823 // Check that the member type of the array is complete, at least. 3824 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3825 diag::err_typecheck_decl_incomplete_type)) 3826 IDecl->setInvalidDecl(); 3827 } else if (RequireCompleteType(IDecl->getLocation(), T, 3828 diag::err_typecheck_decl_incomplete_type)) 3829 IDecl->setInvalidDecl(); 3830 } 3831 } 3832 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3833 // object that has file scope without an initializer, and without a 3834 // storage-class specifier or with the storage-class specifier "static", 3835 // constitutes a tentative definition. Note: A tentative definition with 3836 // external linkage is valid (C99 6.2.2p5). 3837 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3838 if (const IncompleteArrayType *ArrayT 3839 = Context.getAsIncompleteArrayType(T)) { 3840 if (RequireCompleteType(IDecl->getLocation(), 3841 ArrayT->getElementType(), 3842 diag::err_illegal_decl_array_incomplete_type)) 3843 IDecl->setInvalidDecl(); 3844 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3845 // C99 6.9.2p3: If the declaration of an identifier for an object is 3846 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3847 // declared type shall not be an incomplete type. 3848 // NOTE: code such as the following 3849 // static struct s; 3850 // struct s { int a; }; 3851 // is accepted by gcc. Hence here we issue a warning instead of 3852 // an error and we do not invalidate the static declaration. 3853 // NOTE: to avoid multiple warnings, only check the first declaration. 3854 if (IDecl->getPreviousDeclaration() == 0) 3855 RequireCompleteType(IDecl->getLocation(), T, 3856 diag::ext_typecheck_decl_incomplete_type); 3857 } 3858 } 3859 } 3860 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3861 Decls.data(), Decls.size())); 3862} 3863 3864 3865/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3866/// to introduce parameters into function prototype scope. 3867Sema::DeclPtrTy 3868Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3869 const DeclSpec &DS = D.getDeclSpec(); 3870 3871 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3872 VarDecl::StorageClass StorageClass = VarDecl::None; 3873 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3874 StorageClass = VarDecl::Register; 3875 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3876 Diag(DS.getStorageClassSpecLoc(), 3877 diag::err_invalid_storage_class_in_func_decl); 3878 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3879 } 3880 3881 if (D.getDeclSpec().isThreadSpecified()) 3882 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3883 3884 DiagnoseFunctionSpecifiers(D); 3885 3886 // Check that there are no default arguments inside the type of this 3887 // parameter (C++ only). 3888 if (getLangOptions().CPlusPlus) 3889 CheckExtraCXXDefaultArguments(D); 3890 3891 TypeSourceInfo *TInfo = 0; 3892 TagDecl *OwnedDecl = 0; 3893 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3894 3895 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3896 // C++ [dcl.fct]p6: 3897 // Types shall not be defined in return or parameter types. 3898 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3899 << Context.getTypeDeclType(OwnedDecl); 3900 } 3901 3902 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3903 // Can this happen for params? We already checked that they don't conflict 3904 // among each other. Here they can only shadow globals, which is ok. 3905 IdentifierInfo *II = D.getIdentifier(); 3906 if (II) { 3907 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3908 if (PrevDecl->isTemplateParameter()) { 3909 // Maybe we will complain about the shadowed template parameter. 3910 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3911 // Just pretend that we didn't see the previous declaration. 3912 PrevDecl = 0; 3913 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3914 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3915 3916 // Recover by removing the name 3917 II = 0; 3918 D.SetIdentifier(0, D.getIdentifierLoc()); 3919 } 3920 } 3921 } 3922 3923 // Parameters can not be abstract class types. 3924 // For record types, this is done by the AbstractClassUsageDiagnoser once 3925 // the class has been completely parsed. 3926 if (!CurContext->isRecord() && 3927 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3928 diag::err_abstract_type_in_decl, 3929 AbstractParamType)) 3930 D.setInvalidType(true); 3931 3932 QualType T = adjustParameterType(parmDeclType); 3933 3934 ParmVarDecl *New 3935 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3936 T, TInfo, StorageClass, 0); 3937 3938 if (D.isInvalidType()) 3939 New->setInvalidDecl(); 3940 3941 // Parameter declarators cannot be interface types. All ObjC objects are 3942 // passed by reference. 3943 if (T->isObjCInterfaceType()) { 3944 Diag(D.getIdentifierLoc(), 3945 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3946 New->setInvalidDecl(); 3947 } 3948 3949 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3950 if (D.getCXXScopeSpec().isSet()) { 3951 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3952 << D.getCXXScopeSpec().getRange(); 3953 New->setInvalidDecl(); 3954 } 3955 3956 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3957 // duration shall not be qualified by an address-space qualifier." 3958 // Since all parameters have automatic store duration, they can not have 3959 // an address space. 3960 if (T.getAddressSpace() != 0) { 3961 Diag(D.getIdentifierLoc(), 3962 diag::err_arg_with_address_space); 3963 New->setInvalidDecl(); 3964 } 3965 3966 3967 // Add the parameter declaration into this scope. 3968 S->AddDecl(DeclPtrTy::make(New)); 3969 if (II) 3970 IdResolver.AddDecl(New); 3971 3972 ProcessDeclAttributes(S, New, D); 3973 3974 if (New->hasAttr<BlocksAttr>()) { 3975 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3976 } 3977 return DeclPtrTy::make(New); 3978} 3979 3980void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3981 SourceLocation LocAfterDecls) { 3982 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3983 "Not a function declarator!"); 3984 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3985 3986 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3987 // for a K&R function. 3988 if (!FTI.hasPrototype) { 3989 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3990 --i; 3991 if (FTI.ArgInfo[i].Param == 0) { 3992 llvm::SmallString<256> Code; 3993 llvm::raw_svector_ostream(Code) << " int " 3994 << FTI.ArgInfo[i].Ident->getName() 3995 << ";\n"; 3996 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3997 << FTI.ArgInfo[i].Ident 3998 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3999 4000 // Implicitly declare the argument as type 'int' for lack of a better 4001 // type. 4002 DeclSpec DS; 4003 const char* PrevSpec; // unused 4004 unsigned DiagID; // unused 4005 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4006 PrevSpec, DiagID); 4007 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4008 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4009 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4010 } 4011 } 4012 } 4013} 4014 4015Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4016 Declarator &D) { 4017 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4018 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4019 "Not a function declarator!"); 4020 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4021 4022 if (FTI.hasPrototype) { 4023 // FIXME: Diagnose arguments without names in C. 4024 } 4025 4026 Scope *ParentScope = FnBodyScope->getParent(); 4027 4028 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4029 MultiTemplateParamsArg(*this), 4030 /*IsFunctionDefinition=*/true); 4031 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4032} 4033 4034static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4035 // Don't warn about invalid declarations. 4036 if (FD->isInvalidDecl()) 4037 return false; 4038 4039 // Or declarations that aren't global. 4040 if (!FD->isGlobal()) 4041 return false; 4042 4043 // Don't warn about C++ member functions. 4044 if (isa<CXXMethodDecl>(FD)) 4045 return false; 4046 4047 // Don't warn about 'main'. 4048 if (FD->isMain()) 4049 return false; 4050 4051 // Don't warn about inline functions. 4052 if (FD->isInlineSpecified()) 4053 return false; 4054 4055 // Don't warn about function templates. 4056 if (FD->getDescribedFunctionTemplate()) 4057 return false; 4058 4059 // Don't warn about function template specializations. 4060 if (FD->isFunctionTemplateSpecialization()) 4061 return false; 4062 4063 bool MissingPrototype = true; 4064 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4065 Prev; Prev = Prev->getPreviousDeclaration()) { 4066 // Ignore any declarations that occur in function or method 4067 // scope, because they aren't visible from the header. 4068 if (Prev->getDeclContext()->isFunctionOrMethod()) 4069 continue; 4070 4071 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4072 break; 4073 } 4074 4075 return MissingPrototype; 4076} 4077 4078Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4079 // Clear the last template instantiation error context. 4080 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4081 4082 if (!D) 4083 return D; 4084 FunctionDecl *FD = 0; 4085 4086 if (FunctionTemplateDecl *FunTmpl 4087 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4088 FD = FunTmpl->getTemplatedDecl(); 4089 else 4090 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4091 4092 CurFunctionNeedsScopeChecking = false; 4093 4094 // See if this is a redefinition. 4095 const FunctionDecl *Definition; 4096 if (FD->getBody(Definition)) { 4097 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4098 Diag(Definition->getLocation(), diag::note_previous_definition); 4099 } 4100 4101 // Builtin functions cannot be defined. 4102 if (unsigned BuiltinID = FD->getBuiltinID()) { 4103 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4104 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4105 FD->setInvalidDecl(); 4106 } 4107 } 4108 4109 // The return type of a function definition must be complete 4110 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4111 QualType ResultType = FD->getResultType(); 4112 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4113 !FD->isInvalidDecl() && 4114 RequireCompleteType(FD->getLocation(), ResultType, 4115 diag::err_func_def_incomplete_result)) 4116 FD->setInvalidDecl(); 4117 4118 // GNU warning -Wmissing-prototypes: 4119 // Warn if a global function is defined without a previous 4120 // prototype declaration. This warning is issued even if the 4121 // definition itself provides a prototype. The aim is to detect 4122 // global functions that fail to be declared in header files. 4123 if (ShouldWarnAboutMissingPrototype(FD)) 4124 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4125 4126 if (FnBodyScope) 4127 PushDeclContext(FnBodyScope, FD); 4128 4129 // Check the validity of our function parameters 4130 CheckParmsForFunctionDef(FD); 4131 4132 // Introduce our parameters into the function scope 4133 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4134 ParmVarDecl *Param = FD->getParamDecl(p); 4135 Param->setOwningFunction(FD); 4136 4137 // If this has an identifier, add it to the scope stack. 4138 if (Param->getIdentifier() && FnBodyScope) 4139 PushOnScopeChains(Param, FnBodyScope); 4140 } 4141 4142 // Checking attributes of current function definition 4143 // dllimport attribute. 4144 if (FD->getAttr<DLLImportAttr>() && 4145 (!FD->getAttr<DLLExportAttr>())) { 4146 // dllimport attribute cannot be applied to definition. 4147 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4148 Diag(FD->getLocation(), 4149 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4150 << "dllimport"; 4151 FD->setInvalidDecl(); 4152 return DeclPtrTy::make(FD); 4153 } else { 4154 // If a symbol previously declared dllimport is later defined, the 4155 // attribute is ignored in subsequent references, and a warning is 4156 // emitted. 4157 Diag(FD->getLocation(), 4158 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4159 << FD->getNameAsCString() << "dllimport"; 4160 } 4161 } 4162 return DeclPtrTy::make(FD); 4163} 4164 4165Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4166 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4167} 4168 4169Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4170 bool IsInstantiation) { 4171 Decl *dcl = D.getAs<Decl>(); 4172 Stmt *Body = BodyArg.takeAs<Stmt>(); 4173 4174 FunctionDecl *FD = 0; 4175 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4176 if (FunTmpl) 4177 FD = FunTmpl->getTemplatedDecl(); 4178 else 4179 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4180 4181 if (FD) { 4182 FD->setBody(Body); 4183 if (FD->isMain()) 4184 // C and C++ allow for main to automagically return 0. 4185 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4186 FD->setHasImplicitReturnZero(true); 4187 else 4188 CheckFallThroughForFunctionDef(FD, Body); 4189 4190 if (!FD->isInvalidDecl()) 4191 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4192 4193 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4194 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4195 4196 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4197 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4198 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4199 MD->setBody(Body); 4200 CheckFallThroughForFunctionDef(MD, Body); 4201 MD->setEndLoc(Body->getLocEnd()); 4202 4203 if (!MD->isInvalidDecl()) 4204 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4205 } else { 4206 Body->Destroy(Context); 4207 return DeclPtrTy(); 4208 } 4209 if (!IsInstantiation) 4210 PopDeclContext(); 4211 4212 // Verify and clean out per-function state. 4213 4214 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4215 4216 // Check goto/label use. 4217 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4218 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4219 LabelStmt *L = I->second; 4220 4221 // Verify that we have no forward references left. If so, there was a goto 4222 // or address of a label taken, but no definition of it. Label fwd 4223 // definitions are indicated with a null substmt. 4224 if (L->getSubStmt() != 0) 4225 continue; 4226 4227 // Emit error. 4228 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4229 4230 // At this point, we have gotos that use the bogus label. Stitch it into 4231 // the function body so that they aren't leaked and that the AST is well 4232 // formed. 4233 if (Body == 0) { 4234 // The whole function wasn't parsed correctly, just delete this. 4235 L->Destroy(Context); 4236 continue; 4237 } 4238 4239 // Otherwise, the body is valid: we want to stitch the label decl into the 4240 // function somewhere so that it is properly owned and so that the goto 4241 // has a valid target. Do this by creating a new compound stmt with the 4242 // label in it. 4243 4244 // Give the label a sub-statement. 4245 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4246 4247 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4248 cast<CXXTryStmt>(Body)->getTryBlock() : 4249 cast<CompoundStmt>(Body); 4250 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4251 Elements.push_back(L); 4252 Compound->setStmts(Context, &Elements[0], Elements.size()); 4253 } 4254 FunctionLabelMap.clear(); 4255 4256 if (!Body) return D; 4257 4258 // Verify that that gotos and switch cases don't jump into scopes illegally. 4259 if (CurFunctionNeedsScopeChecking) 4260 DiagnoseInvalidJumps(Body); 4261 4262 // C++ constructors that have function-try-blocks can't have return 4263 // statements in the handlers of that block. (C++ [except.handle]p14) 4264 // Verify this. 4265 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4266 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4267 4268 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4269 MarkBaseAndMemberDestructorsReferenced(Destructor); 4270 4271 // If any errors have occurred, clear out any temporaries that may have 4272 // been leftover. This ensures that these temporaries won't be picked up for 4273 // deletion in some later function. 4274 if (PP.getDiagnostics().hasErrorOccurred()) 4275 ExprTemporaries.clear(); 4276 4277 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4278 return D; 4279} 4280 4281/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4282/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4283NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4284 IdentifierInfo &II, Scope *S) { 4285 // Before we produce a declaration for an implicitly defined 4286 // function, see whether there was a locally-scoped declaration of 4287 // this name as a function or variable. If so, use that 4288 // (non-visible) declaration, and complain about it. 4289 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4290 = LocallyScopedExternalDecls.find(&II); 4291 if (Pos != LocallyScopedExternalDecls.end()) { 4292 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4293 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4294 return Pos->second; 4295 } 4296 4297 // Extension in C99. Legal in C90, but warn about it. 4298 if (II.getName().startswith("__builtin_")) 4299 Diag(Loc, diag::warn_builtin_unknown) << &II; 4300 else if (getLangOptions().C99) 4301 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4302 else 4303 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4304 4305 // Set a Declarator for the implicit definition: int foo(); 4306 const char *Dummy; 4307 DeclSpec DS; 4308 unsigned DiagID; 4309 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4310 Error = Error; // Silence warning. 4311 assert(!Error && "Error setting up implicit decl!"); 4312 Declarator D(DS, Declarator::BlockContext); 4313 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4314 0, 0, false, SourceLocation(), 4315 false, 0,0,0, Loc, Loc, D), 4316 SourceLocation()); 4317 D.SetIdentifier(&II, Loc); 4318 4319 // Insert this function into translation-unit scope. 4320 4321 DeclContext *PrevDC = CurContext; 4322 CurContext = Context.getTranslationUnitDecl(); 4323 4324 FunctionDecl *FD = 4325 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4326 FD->setImplicit(); 4327 4328 CurContext = PrevDC; 4329 4330 AddKnownFunctionAttributes(FD); 4331 4332 return FD; 4333} 4334 4335/// \brief Adds any function attributes that we know a priori based on 4336/// the declaration of this function. 4337/// 4338/// These attributes can apply both to implicitly-declared builtins 4339/// (like __builtin___printf_chk) or to library-declared functions 4340/// like NSLog or printf. 4341void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4342 if (FD->isInvalidDecl()) 4343 return; 4344 4345 // If this is a built-in function, map its builtin attributes to 4346 // actual attributes. 4347 if (unsigned BuiltinID = FD->getBuiltinID()) { 4348 // Handle printf-formatting attributes. 4349 unsigned FormatIdx; 4350 bool HasVAListArg; 4351 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4352 if (!FD->getAttr<FormatAttr>()) 4353 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4354 HasVAListArg ? 0 : FormatIdx + 2)); 4355 } 4356 4357 // Mark const if we don't care about errno and that is the only 4358 // thing preventing the function from being const. This allows 4359 // IRgen to use LLVM intrinsics for such functions. 4360 if (!getLangOptions().MathErrno && 4361 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4362 if (!FD->getAttr<ConstAttr>()) 4363 FD->addAttr(::new (Context) ConstAttr()); 4364 } 4365 4366 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4367 FD->addAttr(::new (Context) NoReturnAttr()); 4368 } 4369 4370 IdentifierInfo *Name = FD->getIdentifier(); 4371 if (!Name) 4372 return; 4373 if ((!getLangOptions().CPlusPlus && 4374 FD->getDeclContext()->isTranslationUnit()) || 4375 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4376 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4377 LinkageSpecDecl::lang_c)) { 4378 // Okay: this could be a libc/libm/Objective-C function we know 4379 // about. 4380 } else 4381 return; 4382 4383 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4384 // FIXME: NSLog and NSLogv should be target specific 4385 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4386 // FIXME: We known better than our headers. 4387 const_cast<FormatAttr *>(Format)->setType("printf"); 4388 } else 4389 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4390 Name->isStr("NSLogv") ? 0 : 2)); 4391 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4392 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4393 // target-specific builtins, perhaps? 4394 if (!FD->getAttr<FormatAttr>()) 4395 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4396 Name->isStr("vasprintf") ? 0 : 3)); 4397 } 4398} 4399 4400TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4401 TypeSourceInfo *TInfo) { 4402 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4403 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4404 4405 if (!TInfo) { 4406 assert(D.isInvalidType() && "no declarator info for valid type"); 4407 TInfo = Context.getTrivialTypeSourceInfo(T); 4408 } 4409 4410 // Scope manipulation handled by caller. 4411 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4412 D.getIdentifierLoc(), 4413 D.getIdentifier(), 4414 TInfo); 4415 4416 if (const TagType *TT = T->getAs<TagType>()) { 4417 TagDecl *TD = TT->getDecl(); 4418 4419 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4420 // keep track of the TypedefDecl. 4421 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4422 TD->setTypedefForAnonDecl(NewTD); 4423 } 4424 4425 if (D.isInvalidType()) 4426 NewTD->setInvalidDecl(); 4427 return NewTD; 4428} 4429 4430 4431/// \brief Determine whether a tag with a given kind is acceptable 4432/// as a redeclaration of the given tag declaration. 4433/// 4434/// \returns true if the new tag kind is acceptable, false otherwise. 4435bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4436 TagDecl::TagKind NewTag, 4437 SourceLocation NewTagLoc, 4438 const IdentifierInfo &Name) { 4439 // C++ [dcl.type.elab]p3: 4440 // The class-key or enum keyword present in the 4441 // elaborated-type-specifier shall agree in kind with the 4442 // declaration to which the name in theelaborated-type-specifier 4443 // refers. This rule also applies to the form of 4444 // elaborated-type-specifier that declares a class-name or 4445 // friend class since it can be construed as referring to the 4446 // definition of the class. Thus, in any 4447 // elaborated-type-specifier, the enum keyword shall be used to 4448 // refer to an enumeration (7.2), the union class-keyshall be 4449 // used to refer to a union (clause 9), and either the class or 4450 // struct class-key shall be used to refer to a class (clause 9) 4451 // declared using the class or struct class-key. 4452 TagDecl::TagKind OldTag = Previous->getTagKind(); 4453 if (OldTag == NewTag) 4454 return true; 4455 4456 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4457 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4458 // Warn about the struct/class tag mismatch. 4459 bool isTemplate = false; 4460 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4461 isTemplate = Record->getDescribedClassTemplate(); 4462 4463 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4464 << (NewTag == TagDecl::TK_class) 4465 << isTemplate << &Name 4466 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4467 OldTag == TagDecl::TK_class? "class" : "struct"); 4468 Diag(Previous->getLocation(), diag::note_previous_use); 4469 return true; 4470 } 4471 return false; 4472} 4473 4474/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4475/// former case, Name will be non-null. In the later case, Name will be null. 4476/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4477/// reference/declaration/definition of a tag. 4478Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4479 SourceLocation KWLoc, const CXXScopeSpec &SS, 4480 IdentifierInfo *Name, SourceLocation NameLoc, 4481 AttributeList *Attr, AccessSpecifier AS, 4482 MultiTemplateParamsArg TemplateParameterLists, 4483 bool &OwnedDecl, bool &IsDependent) { 4484 // If this is not a definition, it must have a name. 4485 assert((Name != 0 || TUK == TUK_Definition) && 4486 "Nameless record must be a definition!"); 4487 4488 OwnedDecl = false; 4489 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4490 4491 // FIXME: Check explicit specializations more carefully. 4492 bool isExplicitSpecialization = false; 4493 if (TUK != TUK_Reference) { 4494 if (TemplateParameterList *TemplateParams 4495 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4496 (TemplateParameterList**)TemplateParameterLists.get(), 4497 TemplateParameterLists.size(), 4498 isExplicitSpecialization)) { 4499 if (TemplateParams->size() > 0) { 4500 // This is a declaration or definition of a class template (which may 4501 // be a member of another template). 4502 OwnedDecl = false; 4503 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4504 SS, Name, NameLoc, Attr, 4505 TemplateParams, 4506 AS); 4507 TemplateParameterLists.release(); 4508 return Result.get(); 4509 } else { 4510 // The "template<>" header is extraneous. 4511 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4512 << ElaboratedType::getNameForTagKind(Kind) << Name; 4513 isExplicitSpecialization = true; 4514 } 4515 } 4516 4517 TemplateParameterLists.release(); 4518 } 4519 4520 DeclContext *SearchDC = CurContext; 4521 DeclContext *DC = CurContext; 4522 bool isStdBadAlloc = false; 4523 bool Invalid = false; 4524 4525 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4526 : NotForRedeclaration); 4527 4528 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4529 4530 if (Name && SS.isNotEmpty()) { 4531 // We have a nested-name tag ('struct foo::bar'). 4532 4533 // Check for invalid 'foo::'. 4534 if (SS.isInvalid()) { 4535 Name = 0; 4536 goto CreateNewDecl; 4537 } 4538 4539 // If this is a friend or a reference to a class in a dependent 4540 // context, don't try to make a decl for it. 4541 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4542 DC = computeDeclContext(SS, false); 4543 if (!DC) { 4544 IsDependent = true; 4545 return DeclPtrTy(); 4546 } 4547 } 4548 4549 if (RequireCompleteDeclContext(SS)) 4550 return DeclPtrTy::make((Decl *)0); 4551 4552 DC = computeDeclContext(SS, true); 4553 SearchDC = DC; 4554 // Look-up name inside 'foo::'. 4555 LookupQualifiedName(Previous, DC); 4556 4557 if (Previous.isAmbiguous()) 4558 return DeclPtrTy(); 4559 4560 // A tag 'foo::bar' must already exist. 4561 if (Previous.empty()) { 4562 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4563 Name = 0; 4564 Invalid = true; 4565 goto CreateNewDecl; 4566 } 4567 } else if (Name) { 4568 // If this is a named struct, check to see if there was a previous forward 4569 // declaration or definition. 4570 // FIXME: We're looking into outer scopes here, even when we 4571 // shouldn't be. Doing so can result in ambiguities that we 4572 // shouldn't be diagnosing. 4573 LookupName(Previous, S); 4574 4575 // Note: there used to be some attempt at recovery here. 4576 if (Previous.isAmbiguous()) 4577 return DeclPtrTy(); 4578 4579 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4580 // FIXME: This makes sure that we ignore the contexts associated 4581 // with C structs, unions, and enums when looking for a matching 4582 // tag declaration or definition. See the similar lookup tweak 4583 // in Sema::LookupName; is there a better way to deal with this? 4584 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4585 SearchDC = SearchDC->getParent(); 4586 } 4587 } 4588 4589 if (Previous.isSingleResult() && 4590 Previous.getFoundDecl()->isTemplateParameter()) { 4591 // Maybe we will complain about the shadowed template parameter. 4592 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4593 // Just pretend that we didn't see the previous declaration. 4594 Previous.clear(); 4595 } 4596 4597 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4598 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4599 // This is a declaration of or a reference to "std::bad_alloc". 4600 isStdBadAlloc = true; 4601 4602 if (Previous.empty() && StdBadAlloc) { 4603 // std::bad_alloc has been implicitly declared (but made invisible to 4604 // name lookup). Fill in this implicit declaration as the previous 4605 // declaration, so that the declarations get chained appropriately. 4606 Previous.addDecl(StdBadAlloc); 4607 } 4608 } 4609 4610 if (!Previous.empty()) { 4611 assert(Previous.isSingleResult()); 4612 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4613 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4614 // If this is a use of a previous tag, or if the tag is already declared 4615 // in the same scope (so that the definition/declaration completes or 4616 // rementions the tag), reuse the decl. 4617 if (TUK == TUK_Reference || TUK == TUK_Friend || 4618 isDeclInScope(PrevDecl, SearchDC, S)) { 4619 // Make sure that this wasn't declared as an enum and now used as a 4620 // struct or something similar. 4621 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4622 bool SafeToContinue 4623 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4624 Kind != TagDecl::TK_enum); 4625 if (SafeToContinue) 4626 Diag(KWLoc, diag::err_use_with_wrong_tag) 4627 << Name 4628 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4629 PrevTagDecl->getKindName()); 4630 else 4631 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4632 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4633 4634 if (SafeToContinue) 4635 Kind = PrevTagDecl->getTagKind(); 4636 else { 4637 // Recover by making this an anonymous redefinition. 4638 Name = 0; 4639 Previous.clear(); 4640 Invalid = true; 4641 } 4642 } 4643 4644 if (!Invalid) { 4645 // If this is a use, just return the declaration we found. 4646 4647 // FIXME: In the future, return a variant or some other clue 4648 // for the consumer of this Decl to know it doesn't own it. 4649 // For our current ASTs this shouldn't be a problem, but will 4650 // need to be changed with DeclGroups. 4651 if (TUK == TUK_Reference || TUK == TUK_Friend) 4652 return DeclPtrTy::make(PrevTagDecl); 4653 4654 // Diagnose attempts to redefine a tag. 4655 if (TUK == TUK_Definition) { 4656 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4657 // If we're defining a specialization and the previous definition 4658 // is from an implicit instantiation, don't emit an error 4659 // here; we'll catch this in the general case below. 4660 if (!isExplicitSpecialization || 4661 !isa<CXXRecordDecl>(Def) || 4662 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4663 == TSK_ExplicitSpecialization) { 4664 Diag(NameLoc, diag::err_redefinition) << Name; 4665 Diag(Def->getLocation(), diag::note_previous_definition); 4666 // If this is a redefinition, recover by making this 4667 // struct be anonymous, which will make any later 4668 // references get the previous definition. 4669 Name = 0; 4670 Previous.clear(); 4671 Invalid = true; 4672 } 4673 } else { 4674 // If the type is currently being defined, complain 4675 // about a nested redefinition. 4676 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4677 if (Tag->isBeingDefined()) { 4678 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4679 Diag(PrevTagDecl->getLocation(), 4680 diag::note_previous_definition); 4681 Name = 0; 4682 Previous.clear(); 4683 Invalid = true; 4684 } 4685 } 4686 4687 // Okay, this is definition of a previously declared or referenced 4688 // tag PrevDecl. We're going to create a new Decl for it. 4689 } 4690 } 4691 // If we get here we have (another) forward declaration or we 4692 // have a definition. Just create a new decl. 4693 4694 } else { 4695 // If we get here, this is a definition of a new tag type in a nested 4696 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4697 // new decl/type. We set PrevDecl to NULL so that the entities 4698 // have distinct types. 4699 Previous.clear(); 4700 } 4701 // If we get here, we're going to create a new Decl. If PrevDecl 4702 // is non-NULL, it's a definition of the tag declared by 4703 // PrevDecl. If it's NULL, we have a new definition. 4704 } else { 4705 // PrevDecl is a namespace, template, or anything else 4706 // that lives in the IDNS_Tag identifier namespace. 4707 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4708 // The tag name clashes with a namespace name, issue an error and 4709 // recover by making this tag be anonymous. 4710 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4711 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4712 Name = 0; 4713 Previous.clear(); 4714 Invalid = true; 4715 } else { 4716 // The existing declaration isn't relevant to us; we're in a 4717 // new scope, so clear out the previous declaration. 4718 Previous.clear(); 4719 } 4720 } 4721 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4722 // C++ [basic.scope.pdecl]p5: 4723 // -- for an elaborated-type-specifier of the form 4724 // 4725 // class-key identifier 4726 // 4727 // if the elaborated-type-specifier is used in the 4728 // decl-specifier-seq or parameter-declaration-clause of a 4729 // function defined in namespace scope, the identifier is 4730 // declared as a class-name in the namespace that contains 4731 // the declaration; otherwise, except as a friend 4732 // declaration, the identifier is declared in the smallest 4733 // non-class, non-function-prototype scope that contains the 4734 // declaration. 4735 // 4736 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4737 // C structs and unions. 4738 // 4739 // It is an error in C++ to declare (rather than define) an enum 4740 // type, including via an elaborated type specifier. We'll 4741 // diagnose that later; for now, declare the enum in the same 4742 // scope as we would have picked for any other tag type. 4743 // 4744 // GNU C also supports this behavior as part of its incomplete 4745 // enum types extension, while GNU C++ does not. 4746 // 4747 // Find the context where we'll be declaring the tag. 4748 // FIXME: We would like to maintain the current DeclContext as the 4749 // lexical context, 4750 while (SearchDC->isRecord()) 4751 SearchDC = SearchDC->getParent(); 4752 4753 // Find the scope where we'll be declaring the tag. 4754 while (S->isClassScope() || 4755 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4756 ((S->getFlags() & Scope::DeclScope) == 0) || 4757 (S->getEntity() && 4758 ((DeclContext *)S->getEntity())->isTransparentContext())) 4759 S = S->getParent(); 4760 4761 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4762 // C++ [namespace.memdef]p3: 4763 // If a friend declaration in a non-local class first declares a 4764 // class or function, the friend class or function is a member of 4765 // the innermost enclosing namespace. 4766 while (!SearchDC->isFileContext()) 4767 SearchDC = SearchDC->getParent(); 4768 4769 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4770 while (S->getEntity() != SearchDC) 4771 S = S->getParent(); 4772 } 4773 4774CreateNewDecl: 4775 4776 TagDecl *PrevDecl = 0; 4777 if (Previous.isSingleResult()) 4778 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4779 4780 // If there is an identifier, use the location of the identifier as the 4781 // location of the decl, otherwise use the location of the struct/union 4782 // keyword. 4783 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4784 4785 // Otherwise, create a new declaration. If there is a previous 4786 // declaration of the same entity, the two will be linked via 4787 // PrevDecl. 4788 TagDecl *New; 4789 4790 if (Kind == TagDecl::TK_enum) { 4791 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4792 // enum X { A, B, C } D; D should chain to X. 4793 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4794 cast_or_null<EnumDecl>(PrevDecl)); 4795 // If this is an undefined enum, warn. 4796 if (TUK != TUK_Definition && !Invalid) { 4797 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4798 : diag::ext_forward_ref_enum; 4799 Diag(Loc, DK); 4800 } 4801 } else { 4802 // struct/union/class 4803 4804 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4805 // struct X { int A; } D; D should chain to X. 4806 if (getLangOptions().CPlusPlus) { 4807 // FIXME: Look for a way to use RecordDecl for simple structs. 4808 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4809 cast_or_null<CXXRecordDecl>(PrevDecl)); 4810 4811 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4812 StdBadAlloc = cast<CXXRecordDecl>(New); 4813 } else 4814 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4815 cast_or_null<RecordDecl>(PrevDecl)); 4816 } 4817 4818 if (Kind != TagDecl::TK_enum) { 4819 // Handle #pragma pack: if the #pragma pack stack has non-default 4820 // alignment, make up a packed attribute for this decl. These 4821 // attributes are checked when the ASTContext lays out the 4822 // structure. 4823 // 4824 // It is important for implementing the correct semantics that this 4825 // happen here (in act on tag decl). The #pragma pack stack is 4826 // maintained as a result of parser callbacks which can occur at 4827 // many points during the parsing of a struct declaration (because 4828 // the #pragma tokens are effectively skipped over during the 4829 // parsing of the struct). 4830 if (unsigned Alignment = getPragmaPackAlignment()) 4831 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4832 } 4833 4834 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4835 // C++ [dcl.typedef]p3: 4836 // [...] Similarly, in a given scope, a class or enumeration 4837 // shall not be declared with the same name as a typedef-name 4838 // that is declared in that scope and refers to a type other 4839 // than the class or enumeration itself. 4840 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4841 ForRedeclaration); 4842 LookupName(Lookup, S); 4843 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4844 NamedDecl *PrevTypedefNamed = PrevTypedef; 4845 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4846 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4847 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4848 Diag(Loc, diag::err_tag_definition_of_typedef) 4849 << Context.getTypeDeclType(New) 4850 << PrevTypedef->getUnderlyingType(); 4851 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4852 Invalid = true; 4853 } 4854 } 4855 4856 // If this is a specialization of a member class (of a class template), 4857 // check the specialization. 4858 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4859 Invalid = true; 4860 4861 if (Invalid) 4862 New->setInvalidDecl(); 4863 4864 if (Attr) 4865 ProcessDeclAttributeList(S, New, Attr); 4866 4867 // If we're declaring or defining a tag in function prototype scope 4868 // in C, note that this type can only be used within the function. 4869 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4870 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4871 4872 // Set the lexical context. If the tag has a C++ scope specifier, the 4873 // lexical context will be different from the semantic context. 4874 New->setLexicalDeclContext(CurContext); 4875 4876 // Mark this as a friend decl if applicable. 4877 if (TUK == TUK_Friend) 4878 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4879 4880 // Set the access specifier. 4881 if (!Invalid && TUK != TUK_Friend) 4882 SetMemberAccessSpecifier(New, PrevDecl, AS); 4883 4884 if (TUK == TUK_Definition) 4885 New->startDefinition(); 4886 4887 // If this has an identifier, add it to the scope stack. 4888 if (TUK == TUK_Friend) { 4889 // We might be replacing an existing declaration in the lookup tables; 4890 // if so, borrow its access specifier. 4891 if (PrevDecl) 4892 New->setAccess(PrevDecl->getAccess()); 4893 4894 // Friend tag decls are visible in fairly strange ways. 4895 if (!CurContext->isDependentContext()) { 4896 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4897 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4898 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4899 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4900 } 4901 } else if (Name) { 4902 S = getNonFieldDeclScope(S); 4903 PushOnScopeChains(New, S); 4904 } else { 4905 CurContext->addDecl(New); 4906 } 4907 4908 // If this is the C FILE type, notify the AST context. 4909 if (IdentifierInfo *II = New->getIdentifier()) 4910 if (!New->isInvalidDecl() && 4911 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4912 II->isStr("FILE")) 4913 Context.setFILEDecl(New); 4914 4915 OwnedDecl = true; 4916 return DeclPtrTy::make(New); 4917} 4918 4919void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4920 AdjustDeclIfTemplate(TagD); 4921 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4922 4923 // Enter the tag context. 4924 PushDeclContext(S, Tag); 4925 4926 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4927 FieldCollector->StartClass(); 4928 4929 if (Record->getIdentifier()) { 4930 // C++ [class]p2: 4931 // [...] The class-name is also inserted into the scope of the 4932 // class itself; this is known as the injected-class-name. For 4933 // purposes of access checking, the injected-class-name is treated 4934 // as if it were a public member name. 4935 CXXRecordDecl *InjectedClassName 4936 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4937 CurContext, Record->getLocation(), 4938 Record->getIdentifier(), 4939 Record->getTagKeywordLoc(), 4940 Record); 4941 InjectedClassName->setImplicit(); 4942 InjectedClassName->setAccess(AS_public); 4943 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4944 InjectedClassName->setDescribedClassTemplate(Template); 4945 PushOnScopeChains(InjectedClassName, S); 4946 assert(InjectedClassName->isInjectedClassName() && 4947 "Broken injected-class-name"); 4948 } 4949 } 4950} 4951 4952void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4953 SourceLocation RBraceLoc) { 4954 AdjustDeclIfTemplate(TagD); 4955 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4956 Tag->setRBraceLoc(RBraceLoc); 4957 4958 if (isa<CXXRecordDecl>(Tag)) 4959 FieldCollector->FinishClass(); 4960 4961 // Exit this scope of this tag's definition. 4962 PopDeclContext(); 4963 4964 // Notify the consumer that we've defined a tag. 4965 Consumer.HandleTagDeclDefinition(Tag); 4966} 4967 4968// Note that FieldName may be null for anonymous bitfields. 4969bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4970 QualType FieldTy, const Expr *BitWidth, 4971 bool *ZeroWidth) { 4972 // Default to true; that shouldn't confuse checks for emptiness 4973 if (ZeroWidth) 4974 *ZeroWidth = true; 4975 4976 // C99 6.7.2.1p4 - verify the field type. 4977 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4978 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4979 // Handle incomplete types with specific error. 4980 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4981 return true; 4982 if (FieldName) 4983 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4984 << FieldName << FieldTy << BitWidth->getSourceRange(); 4985 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4986 << FieldTy << BitWidth->getSourceRange(); 4987 } 4988 4989 // If the bit-width is type- or value-dependent, don't try to check 4990 // it now. 4991 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4992 return false; 4993 4994 llvm::APSInt Value; 4995 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4996 return true; 4997 4998 if (Value != 0 && ZeroWidth) 4999 *ZeroWidth = false; 5000 5001 // Zero-width bitfield is ok for anonymous field. 5002 if (Value == 0 && FieldName) 5003 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5004 5005 if (Value.isSigned() && Value.isNegative()) { 5006 if (FieldName) 5007 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5008 << FieldName << Value.toString(10); 5009 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5010 << Value.toString(10); 5011 } 5012 5013 if (!FieldTy->isDependentType()) { 5014 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5015 if (Value.getZExtValue() > TypeSize) { 5016 if (FieldName) 5017 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5018 << FieldName << (unsigned)TypeSize; 5019 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5020 << (unsigned)TypeSize; 5021 } 5022 } 5023 5024 return false; 5025} 5026 5027/// ActOnField - Each field of a struct/union/class is passed into this in order 5028/// to create a FieldDecl object for it. 5029Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5030 SourceLocation DeclStart, 5031 Declarator &D, ExprTy *BitfieldWidth) { 5032 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5033 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5034 AS_public); 5035 return DeclPtrTy::make(Res); 5036} 5037 5038/// HandleField - Analyze a field of a C struct or a C++ data member. 5039/// 5040FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5041 SourceLocation DeclStart, 5042 Declarator &D, Expr *BitWidth, 5043 AccessSpecifier AS) { 5044 IdentifierInfo *II = D.getIdentifier(); 5045 SourceLocation Loc = DeclStart; 5046 if (II) Loc = D.getIdentifierLoc(); 5047 5048 TypeSourceInfo *TInfo = 0; 5049 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5050 if (getLangOptions().CPlusPlus) 5051 CheckExtraCXXDefaultArguments(D); 5052 5053 DiagnoseFunctionSpecifiers(D); 5054 5055 if (D.getDeclSpec().isThreadSpecified()) 5056 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5057 5058 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5059 ForRedeclaration); 5060 5061 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5062 // Maybe we will complain about the shadowed template parameter. 5063 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5064 // Just pretend that we didn't see the previous declaration. 5065 PrevDecl = 0; 5066 } 5067 5068 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5069 PrevDecl = 0; 5070 5071 bool Mutable 5072 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5073 SourceLocation TSSL = D.getSourceRange().getBegin(); 5074 FieldDecl *NewFD 5075 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5076 AS, PrevDecl, &D); 5077 if (NewFD->isInvalidDecl() && PrevDecl) { 5078 // Don't introduce NewFD into scope; there's already something 5079 // with the same name in the same scope. 5080 } else if (II) { 5081 PushOnScopeChains(NewFD, S); 5082 } else 5083 Record->addDecl(NewFD); 5084 5085 return NewFD; 5086} 5087 5088/// \brief Build a new FieldDecl and check its well-formedness. 5089/// 5090/// This routine builds a new FieldDecl given the fields name, type, 5091/// record, etc. \p PrevDecl should refer to any previous declaration 5092/// with the same name and in the same scope as the field to be 5093/// created. 5094/// 5095/// \returns a new FieldDecl. 5096/// 5097/// \todo The Declarator argument is a hack. It will be removed once 5098FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5099 TypeSourceInfo *TInfo, 5100 RecordDecl *Record, SourceLocation Loc, 5101 bool Mutable, Expr *BitWidth, 5102 SourceLocation TSSL, 5103 AccessSpecifier AS, NamedDecl *PrevDecl, 5104 Declarator *D) { 5105 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5106 bool InvalidDecl = false; 5107 if (D) InvalidDecl = D->isInvalidType(); 5108 5109 // If we receive a broken type, recover by assuming 'int' and 5110 // marking this declaration as invalid. 5111 if (T.isNull()) { 5112 InvalidDecl = true; 5113 T = Context.IntTy; 5114 } 5115 5116 QualType EltTy = Context.getBaseElementType(T); 5117 if (!EltTy->isDependentType() && 5118 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5119 InvalidDecl = true; 5120 5121 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5122 // than a variably modified type. 5123 if (!InvalidDecl && T->isVariablyModifiedType()) { 5124 bool SizeIsNegative; 5125 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5126 SizeIsNegative); 5127 if (!FixedTy.isNull()) { 5128 Diag(Loc, diag::warn_illegal_constant_array_size); 5129 T = FixedTy; 5130 } else { 5131 if (SizeIsNegative) 5132 Diag(Loc, diag::err_typecheck_negative_array_size); 5133 else 5134 Diag(Loc, diag::err_typecheck_field_variable_size); 5135 InvalidDecl = true; 5136 } 5137 } 5138 5139 // Fields can not have abstract class types 5140 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5141 diag::err_abstract_type_in_decl, 5142 AbstractFieldType)) 5143 InvalidDecl = true; 5144 5145 bool ZeroWidth = false; 5146 // If this is declared as a bit-field, check the bit-field. 5147 if (!InvalidDecl && BitWidth && 5148 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5149 InvalidDecl = true; 5150 DeleteExpr(BitWidth); 5151 BitWidth = 0; 5152 ZeroWidth = false; 5153 } 5154 5155 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5156 BitWidth, Mutable); 5157 if (InvalidDecl) 5158 NewFD->setInvalidDecl(); 5159 5160 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5161 Diag(Loc, diag::err_duplicate_member) << II; 5162 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5163 NewFD->setInvalidDecl(); 5164 } 5165 5166 if (getLangOptions().CPlusPlus) { 5167 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5168 5169 if (!T->isPODType()) 5170 CXXRecord->setPOD(false); 5171 if (!ZeroWidth) 5172 CXXRecord->setEmpty(false); 5173 5174 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5175 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5176 5177 if (!RDecl->hasTrivialConstructor()) 5178 CXXRecord->setHasTrivialConstructor(false); 5179 if (!RDecl->hasTrivialCopyConstructor()) 5180 CXXRecord->setHasTrivialCopyConstructor(false); 5181 if (!RDecl->hasTrivialCopyAssignment()) 5182 CXXRecord->setHasTrivialCopyAssignment(false); 5183 if (!RDecl->hasTrivialDestructor()) 5184 CXXRecord->setHasTrivialDestructor(false); 5185 5186 // C++ 9.5p1: An object of a class with a non-trivial 5187 // constructor, a non-trivial copy constructor, a non-trivial 5188 // destructor, or a non-trivial copy assignment operator 5189 // cannot be a member of a union, nor can an array of such 5190 // objects. 5191 // TODO: C++0x alters this restriction significantly. 5192 if (Record->isUnion()) { 5193 // We check for copy constructors before constructors 5194 // because otherwise we'll never get complaints about 5195 // copy constructors. 5196 5197 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5198 5199 CXXSpecialMember member; 5200 if (!RDecl->hasTrivialCopyConstructor()) 5201 member = CXXCopyConstructor; 5202 else if (!RDecl->hasTrivialConstructor()) 5203 member = CXXDefaultConstructor; 5204 else if (!RDecl->hasTrivialCopyAssignment()) 5205 member = CXXCopyAssignment; 5206 else if (!RDecl->hasTrivialDestructor()) 5207 member = CXXDestructor; 5208 else 5209 member = invalid; 5210 5211 if (member != invalid) { 5212 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5213 DiagnoseNontrivial(RT, member); 5214 NewFD->setInvalidDecl(); 5215 } 5216 } 5217 } 5218 } 5219 5220 // FIXME: We need to pass in the attributes given an AST 5221 // representation, not a parser representation. 5222 if (D) 5223 // FIXME: What to pass instead of TUScope? 5224 ProcessDeclAttributes(TUScope, NewFD, *D); 5225 5226 if (T.isObjCGCWeak()) 5227 Diag(Loc, diag::warn_attribute_weak_on_field); 5228 5229 NewFD->setAccess(AS); 5230 5231 // C++ [dcl.init.aggr]p1: 5232 // An aggregate is an array or a class (clause 9) with [...] no 5233 // private or protected non-static data members (clause 11). 5234 // A POD must be an aggregate. 5235 if (getLangOptions().CPlusPlus && 5236 (AS == AS_private || AS == AS_protected)) { 5237 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5238 CXXRecord->setAggregate(false); 5239 CXXRecord->setPOD(false); 5240 } 5241 5242 return NewFD; 5243} 5244 5245/// DiagnoseNontrivial - Given that a class has a non-trivial 5246/// special member, figure out why. 5247void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5248 QualType QT(T, 0U); 5249 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5250 5251 // Check whether the member was user-declared. 5252 switch (member) { 5253 case CXXDefaultConstructor: 5254 if (RD->hasUserDeclaredConstructor()) { 5255 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5256 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5257 const FunctionDecl *body = 0; 5258 ci->getBody(body); 5259 if (!body || 5260 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5261 SourceLocation CtorLoc = ci->getLocation(); 5262 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5263 return; 5264 } 5265 } 5266 5267 assert(0 && "found no user-declared constructors"); 5268 return; 5269 } 5270 break; 5271 5272 case CXXCopyConstructor: 5273 if (RD->hasUserDeclaredCopyConstructor()) { 5274 SourceLocation CtorLoc = 5275 RD->getCopyConstructor(Context, 0)->getLocation(); 5276 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5277 return; 5278 } 5279 break; 5280 5281 case CXXCopyAssignment: 5282 if (RD->hasUserDeclaredCopyAssignment()) { 5283 // FIXME: this should use the location of the copy 5284 // assignment, not the type. 5285 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5286 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5287 return; 5288 } 5289 break; 5290 5291 case CXXDestructor: 5292 if (RD->hasUserDeclaredDestructor()) { 5293 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5294 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5295 return; 5296 } 5297 break; 5298 } 5299 5300 typedef CXXRecordDecl::base_class_iterator base_iter; 5301 5302 // Virtual bases and members inhibit trivial copying/construction, 5303 // but not trivial destruction. 5304 if (member != CXXDestructor) { 5305 // Check for virtual bases. vbases includes indirect virtual bases, 5306 // so we just iterate through the direct bases. 5307 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5308 if (bi->isVirtual()) { 5309 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5310 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5311 return; 5312 } 5313 5314 // Check for virtual methods. 5315 typedef CXXRecordDecl::method_iterator meth_iter; 5316 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5317 ++mi) { 5318 if (mi->isVirtual()) { 5319 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5320 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5321 return; 5322 } 5323 } 5324 } 5325 5326 bool (CXXRecordDecl::*hasTrivial)() const; 5327 switch (member) { 5328 case CXXDefaultConstructor: 5329 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5330 case CXXCopyConstructor: 5331 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5332 case CXXCopyAssignment: 5333 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5334 case CXXDestructor: 5335 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5336 default: 5337 assert(0 && "unexpected special member"); return; 5338 } 5339 5340 // Check for nontrivial bases (and recurse). 5341 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5342 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5343 assert(BaseRT && "Don't know how to handle dependent bases"); 5344 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5345 if (!(BaseRecTy->*hasTrivial)()) { 5346 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5347 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5348 DiagnoseNontrivial(BaseRT, member); 5349 return; 5350 } 5351 } 5352 5353 // Check for nontrivial members (and recurse). 5354 typedef RecordDecl::field_iterator field_iter; 5355 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5356 ++fi) { 5357 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5358 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5359 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5360 5361 if (!(EltRD->*hasTrivial)()) { 5362 SourceLocation FLoc = (*fi)->getLocation(); 5363 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5364 DiagnoseNontrivial(EltRT, member); 5365 return; 5366 } 5367 } 5368 } 5369 5370 assert(0 && "found no explanation for non-trivial member"); 5371} 5372 5373/// TranslateIvarVisibility - Translate visibility from a token ID to an 5374/// AST enum value. 5375static ObjCIvarDecl::AccessControl 5376TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5377 switch (ivarVisibility) { 5378 default: assert(0 && "Unknown visitibility kind"); 5379 case tok::objc_private: return ObjCIvarDecl::Private; 5380 case tok::objc_public: return ObjCIvarDecl::Public; 5381 case tok::objc_protected: return ObjCIvarDecl::Protected; 5382 case tok::objc_package: return ObjCIvarDecl::Package; 5383 } 5384} 5385 5386/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5387/// in order to create an IvarDecl object for it. 5388Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5389 SourceLocation DeclStart, 5390 DeclPtrTy IntfDecl, 5391 Declarator &D, ExprTy *BitfieldWidth, 5392 tok::ObjCKeywordKind Visibility) { 5393 5394 IdentifierInfo *II = D.getIdentifier(); 5395 Expr *BitWidth = (Expr*)BitfieldWidth; 5396 SourceLocation Loc = DeclStart; 5397 if (II) Loc = D.getIdentifierLoc(); 5398 5399 // FIXME: Unnamed fields can be handled in various different ways, for 5400 // example, unnamed unions inject all members into the struct namespace! 5401 5402 TypeSourceInfo *TInfo = 0; 5403 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5404 5405 if (BitWidth) { 5406 // 6.7.2.1p3, 6.7.2.1p4 5407 if (VerifyBitField(Loc, II, T, BitWidth)) { 5408 D.setInvalidType(); 5409 DeleteExpr(BitWidth); 5410 BitWidth = 0; 5411 } 5412 } else { 5413 // Not a bitfield. 5414 5415 // validate II. 5416 5417 } 5418 5419 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5420 // than a variably modified type. 5421 if (T->isVariablyModifiedType()) { 5422 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5423 D.setInvalidType(); 5424 } 5425 5426 // Get the visibility (access control) for this ivar. 5427 ObjCIvarDecl::AccessControl ac = 5428 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5429 : ObjCIvarDecl::None; 5430 // Must set ivar's DeclContext to its enclosing interface. 5431 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5432 DeclContext *EnclosingContext; 5433 if (ObjCImplementationDecl *IMPDecl = 5434 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5435 // Case of ivar declared in an implementation. Context is that of its class. 5436 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5437 assert(IDecl && "No class- ActOnIvar"); 5438 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5439 } else 5440 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5441 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5442 5443 // Construct the decl. 5444 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5445 EnclosingContext, Loc, II, T, 5446 TInfo, ac, (Expr *)BitfieldWidth); 5447 5448 if (II) { 5449 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5450 ForRedeclaration); 5451 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5452 && !isa<TagDecl>(PrevDecl)) { 5453 Diag(Loc, diag::err_duplicate_member) << II; 5454 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5455 NewID->setInvalidDecl(); 5456 } 5457 } 5458 5459 // Process attributes attached to the ivar. 5460 ProcessDeclAttributes(S, NewID, D); 5461 5462 if (D.isInvalidType()) 5463 NewID->setInvalidDecl(); 5464 5465 if (II) { 5466 // FIXME: When interfaces are DeclContexts, we'll need to add 5467 // these to the interface. 5468 S->AddDecl(DeclPtrTy::make(NewID)); 5469 IdResolver.AddDecl(NewID); 5470 } 5471 5472 return DeclPtrTy::make(NewID); 5473} 5474 5475void Sema::ActOnFields(Scope* S, 5476 SourceLocation RecLoc, DeclPtrTy RecDecl, 5477 DeclPtrTy *Fields, unsigned NumFields, 5478 SourceLocation LBrac, SourceLocation RBrac, 5479 AttributeList *Attr) { 5480 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5481 assert(EnclosingDecl && "missing record or interface decl"); 5482 5483 // If the decl this is being inserted into is invalid, then it may be a 5484 // redeclaration or some other bogus case. Don't try to add fields to it. 5485 if (EnclosingDecl->isInvalidDecl()) { 5486 // FIXME: Deallocate fields? 5487 return; 5488 } 5489 5490 5491 // Verify that all the fields are okay. 5492 unsigned NumNamedMembers = 0; 5493 llvm::SmallVector<FieldDecl*, 32> RecFields; 5494 5495 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5496 for (unsigned i = 0; i != NumFields; ++i) { 5497 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5498 5499 // Get the type for the field. 5500 Type *FDTy = FD->getType().getTypePtr(); 5501 5502 if (!FD->isAnonymousStructOrUnion()) { 5503 // Remember all fields written by the user. 5504 RecFields.push_back(FD); 5505 } 5506 5507 // If the field is already invalid for some reason, don't emit more 5508 // diagnostics about it. 5509 if (FD->isInvalidDecl()) { 5510 EnclosingDecl->setInvalidDecl(); 5511 continue; 5512 } 5513 5514 // C99 6.7.2.1p2: 5515 // A structure or union shall not contain a member with 5516 // incomplete or function type (hence, a structure shall not 5517 // contain an instance of itself, but may contain a pointer to 5518 // an instance of itself), except that the last member of a 5519 // structure with more than one named member may have incomplete 5520 // array type; such a structure (and any union containing, 5521 // possibly recursively, a member that is such a structure) 5522 // shall not be a member of a structure or an element of an 5523 // array. 5524 if (FDTy->isFunctionType()) { 5525 // Field declared as a function. 5526 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5527 << FD->getDeclName(); 5528 FD->setInvalidDecl(); 5529 EnclosingDecl->setInvalidDecl(); 5530 continue; 5531 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5532 Record && Record->isStruct()) { 5533 // Flexible array member. 5534 if (NumNamedMembers < 1) { 5535 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5536 << FD->getDeclName(); 5537 FD->setInvalidDecl(); 5538 EnclosingDecl->setInvalidDecl(); 5539 continue; 5540 } 5541 // Okay, we have a legal flexible array member at the end of the struct. 5542 if (Record) 5543 Record->setHasFlexibleArrayMember(true); 5544 } else if (!FDTy->isDependentType() && 5545 RequireCompleteType(FD->getLocation(), FD->getType(), 5546 diag::err_field_incomplete)) { 5547 // Incomplete type 5548 FD->setInvalidDecl(); 5549 EnclosingDecl->setInvalidDecl(); 5550 continue; 5551 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5552 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5553 // If this is a member of a union, then entire union becomes "flexible". 5554 if (Record && Record->isUnion()) { 5555 Record->setHasFlexibleArrayMember(true); 5556 } else { 5557 // If this is a struct/class and this is not the last element, reject 5558 // it. Note that GCC supports variable sized arrays in the middle of 5559 // structures. 5560 if (i != NumFields-1) 5561 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5562 << FD->getDeclName() << FD->getType(); 5563 else { 5564 // We support flexible arrays at the end of structs in 5565 // other structs as an extension. 5566 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5567 << FD->getDeclName(); 5568 if (Record) 5569 Record->setHasFlexibleArrayMember(true); 5570 } 5571 } 5572 } 5573 if (Record && FDTTy->getDecl()->hasObjectMember()) 5574 Record->setHasObjectMember(true); 5575 } else if (FDTy->isObjCInterfaceType()) { 5576 /// A field cannot be an Objective-c object 5577 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5578 FD->setInvalidDecl(); 5579 EnclosingDecl->setInvalidDecl(); 5580 continue; 5581 } else if (getLangOptions().ObjC1 && 5582 getLangOptions().getGCMode() != LangOptions::NonGC && 5583 Record && 5584 (FD->getType()->isObjCObjectPointerType() || 5585 FD->getType().isObjCGCStrong())) 5586 Record->setHasObjectMember(true); 5587 // Keep track of the number of named members. 5588 if (FD->getIdentifier()) 5589 ++NumNamedMembers; 5590 } 5591 5592 // Okay, we successfully defined 'Record'. 5593 if (Record) { 5594 Record->completeDefinition(Context); 5595 } else { 5596 ObjCIvarDecl **ClsFields = 5597 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5598 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5599 ID->setIVarList(ClsFields, RecFields.size(), Context); 5600 ID->setLocEnd(RBrac); 5601 // Add ivar's to class's DeclContext. 5602 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5603 ClsFields[i]->setLexicalDeclContext(ID); 5604 ID->addDecl(ClsFields[i]); 5605 } 5606 // Must enforce the rule that ivars in the base classes may not be 5607 // duplicates. 5608 if (ID->getSuperClass()) { 5609 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5610 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5611 ObjCIvarDecl* Ivar = (*IVI); 5612 5613 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5614 ObjCIvarDecl* prevIvar = 5615 ID->getSuperClass()->lookupInstanceVariable(II); 5616 if (prevIvar) { 5617 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5618 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5619 } 5620 } 5621 } 5622 } 5623 } else if (ObjCImplementationDecl *IMPDecl = 5624 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5625 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5626 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5627 // Ivar declared in @implementation never belongs to the implementation. 5628 // Only it is in implementation's lexical context. 5629 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5630 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5631 } 5632 } 5633 5634 if (Attr) 5635 ProcessDeclAttributeList(S, Record, Attr); 5636} 5637 5638EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5639 EnumConstantDecl *LastEnumConst, 5640 SourceLocation IdLoc, 5641 IdentifierInfo *Id, 5642 ExprArg val) { 5643 Expr *Val = (Expr *)val.get(); 5644 5645 llvm::APSInt EnumVal(32); 5646 QualType EltTy; 5647 if (Val) { 5648 if (Val->isTypeDependent()) 5649 EltTy = Context.DependentTy; 5650 else { 5651 // Make sure to promote the operand type to int. 5652 UsualUnaryConversions(Val); 5653 if (Val != val.get()) { 5654 val.release(); 5655 val = Val; 5656 } 5657 5658 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5659 SourceLocation ExpLoc; 5660 if (!Val->isValueDependent() && 5661 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5662 Val = 0; 5663 } else { 5664 EltTy = Val->getType(); 5665 } 5666 } 5667 } 5668 5669 if (!Val) { 5670 if (LastEnumConst) { 5671 // Assign the last value + 1. 5672 EnumVal = LastEnumConst->getInitVal(); 5673 ++EnumVal; 5674 5675 // Check for overflow on increment. 5676 if (EnumVal < LastEnumConst->getInitVal()) 5677 Diag(IdLoc, diag::warn_enum_value_overflow); 5678 5679 EltTy = LastEnumConst->getType(); 5680 } else { 5681 // First value, set to zero. 5682 EltTy = Context.IntTy; 5683 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5684 } 5685 } 5686 5687 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5688 5689 val.release(); 5690 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5691 Val, EnumVal); 5692} 5693 5694 5695Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5696 DeclPtrTy lastEnumConst, 5697 SourceLocation IdLoc, 5698 IdentifierInfo *Id, 5699 SourceLocation EqualLoc, ExprTy *val) { 5700 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5701 EnumConstantDecl *LastEnumConst = 5702 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5703 Expr *Val = static_cast<Expr*>(val); 5704 5705 // The scope passed in may not be a decl scope. Zip up the scope tree until 5706 // we find one that is. 5707 S = getNonFieldDeclScope(S); 5708 5709 // Verify that there isn't already something declared with this name in this 5710 // scope. 5711 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5712 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5713 // Maybe we will complain about the shadowed template parameter. 5714 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5715 // Just pretend that we didn't see the previous declaration. 5716 PrevDecl = 0; 5717 } 5718 5719 if (PrevDecl) { 5720 // When in C++, we may get a TagDecl with the same name; in this case the 5721 // enum constant will 'hide' the tag. 5722 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5723 "Received TagDecl when not in C++!"); 5724 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5725 if (isa<EnumConstantDecl>(PrevDecl)) 5726 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5727 else 5728 Diag(IdLoc, diag::err_redefinition) << Id; 5729 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5730 if (Val) Val->Destroy(Context); 5731 return DeclPtrTy(); 5732 } 5733 } 5734 5735 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5736 IdLoc, Id, Owned(Val)); 5737 5738 // Register this decl in the current scope stack. 5739 if (New) 5740 PushOnScopeChains(New, S); 5741 5742 return DeclPtrTy::make(New); 5743} 5744 5745void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5746 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5747 DeclPtrTy *Elements, unsigned NumElements, 5748 Scope *S, AttributeList *Attr) { 5749 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5750 QualType EnumType = Context.getTypeDeclType(Enum); 5751 5752 if (Attr) 5753 ProcessDeclAttributeList(S, Enum, Attr); 5754 5755 // TODO: If the result value doesn't fit in an int, it must be a long or long 5756 // long value. ISO C does not support this, but GCC does as an extension, 5757 // emit a warning. 5758 unsigned IntWidth = Context.Target.getIntWidth(); 5759 unsigned CharWidth = Context.Target.getCharWidth(); 5760 unsigned ShortWidth = Context.Target.getShortWidth(); 5761 5762 // Verify that all the values are okay, compute the size of the values, and 5763 // reverse the list. 5764 unsigned NumNegativeBits = 0; 5765 unsigned NumPositiveBits = 0; 5766 5767 // Keep track of whether all elements have type int. 5768 bool AllElementsInt = true; 5769 5770 for (unsigned i = 0; i != NumElements; ++i) { 5771 EnumConstantDecl *ECD = 5772 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5773 if (!ECD) continue; // Already issued a diagnostic. 5774 5775 // If the enum value doesn't fit in an int, emit an extension warning. 5776 const llvm::APSInt &InitVal = ECD->getInitVal(); 5777 assert(InitVal.getBitWidth() >= IntWidth && 5778 "Should have promoted value to int"); 5779 if (InitVal.getBitWidth() > IntWidth) { 5780 llvm::APSInt V(InitVal); 5781 V.trunc(IntWidth); 5782 V.extend(InitVal.getBitWidth()); 5783 if (V != InitVal) 5784 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5785 << InitVal.toString(10); 5786 } 5787 5788 // Keep track of the size of positive and negative values. 5789 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5790 NumPositiveBits = std::max(NumPositiveBits, 5791 (unsigned)InitVal.getActiveBits()); 5792 else 5793 NumNegativeBits = std::max(NumNegativeBits, 5794 (unsigned)InitVal.getMinSignedBits()); 5795 5796 // Keep track of whether every enum element has type int (very commmon). 5797 if (AllElementsInt) 5798 AllElementsInt = ECD->getType() == Context.IntTy; 5799 } 5800 5801 // Figure out the type that should be used for this enum. 5802 // FIXME: Support -fshort-enums. 5803 QualType BestType; 5804 unsigned BestWidth; 5805 5806 // C++0x N3000 [conv.prom]p3: 5807 // An rvalue of an unscoped enumeration type whose underlying 5808 // type is not fixed can be converted to an rvalue of the first 5809 // of the following types that can represent all the values of 5810 // the enumeration: int, unsigned int, long int, unsigned long 5811 // int, long long int, or unsigned long long int. 5812 // C99 6.4.4.3p2: 5813 // An identifier declared as an enumeration constant has type int. 5814 // The C99 rule is modified by a gcc extension 5815 QualType BestPromotionType; 5816 5817 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5818 5819 if (NumNegativeBits) { 5820 // If there is a negative value, figure out the smallest integer type (of 5821 // int/long/longlong) that fits. 5822 // If it's packed, check also if it fits a char or a short. 5823 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5824 BestType = Context.SignedCharTy; 5825 BestWidth = CharWidth; 5826 } else if (Packed && NumNegativeBits <= ShortWidth && 5827 NumPositiveBits < ShortWidth) { 5828 BestType = Context.ShortTy; 5829 BestWidth = ShortWidth; 5830 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5831 BestType = Context.IntTy; 5832 BestWidth = IntWidth; 5833 } else { 5834 BestWidth = Context.Target.getLongWidth(); 5835 5836 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5837 BestType = Context.LongTy; 5838 } else { 5839 BestWidth = Context.Target.getLongLongWidth(); 5840 5841 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5842 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5843 BestType = Context.LongLongTy; 5844 } 5845 } 5846 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5847 } else { 5848 // If there is no negative value, figure out which of uint, ulong, ulonglong 5849 // fits. 5850 // If it's packed, check also if it fits a char or a short. 5851 if (Packed && NumPositiveBits <= CharWidth) { 5852 BestType = Context.UnsignedCharTy; 5853 BestPromotionType = Context.IntTy; 5854 BestWidth = CharWidth; 5855 } else if (Packed && NumPositiveBits <= ShortWidth) { 5856 BestType = Context.UnsignedShortTy; 5857 BestPromotionType = Context.IntTy; 5858 BestWidth = ShortWidth; 5859 } else if (NumPositiveBits <= IntWidth) { 5860 BestType = Context.UnsignedIntTy; 5861 BestWidth = IntWidth; 5862 BestPromotionType = (NumPositiveBits == BestWidth 5863 ? Context.UnsignedIntTy : Context.IntTy); 5864 } else if (NumPositiveBits <= 5865 (BestWidth = Context.Target.getLongWidth())) { 5866 BestType = Context.UnsignedLongTy; 5867 BestPromotionType = (NumPositiveBits == BestWidth 5868 ? Context.UnsignedLongTy : Context.LongTy); 5869 } else { 5870 BestWidth = Context.Target.getLongLongWidth(); 5871 assert(NumPositiveBits <= BestWidth && 5872 "How could an initializer get larger than ULL?"); 5873 BestType = Context.UnsignedLongLongTy; 5874 BestPromotionType = (NumPositiveBits == BestWidth 5875 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5876 } 5877 } 5878 5879 // If we're in C and the promotion type is larger than an int, just 5880 // use the underlying type, which is generally the unsigned integer 5881 // type of the same rank as the promotion type. This is how the gcc 5882 // extension works. 5883 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5884 BestPromotionType = BestType; 5885 5886 // Loop over all of the enumerator constants, changing their types to match 5887 // the type of the enum if needed. 5888 for (unsigned i = 0; i != NumElements; ++i) { 5889 EnumConstantDecl *ECD = 5890 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5891 if (!ECD) continue; // Already issued a diagnostic. 5892 5893 // Standard C says the enumerators have int type, but we allow, as an 5894 // extension, the enumerators to be larger than int size. If each 5895 // enumerator value fits in an int, type it as an int, otherwise type it the 5896 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5897 // that X has type 'int', not 'unsigned'. 5898 if (ECD->getType() == Context.IntTy) { 5899 // Make sure the init value is signed. 5900 llvm::APSInt IV = ECD->getInitVal(); 5901 IV.setIsSigned(true); 5902 ECD->setInitVal(IV); 5903 5904 if (getLangOptions().CPlusPlus) 5905 // C++ [dcl.enum]p4: Following the closing brace of an 5906 // enum-specifier, each enumerator has the type of its 5907 // enumeration. 5908 ECD->setType(EnumType); 5909 continue; // Already int type. 5910 } 5911 5912 // Determine whether the value fits into an int. 5913 llvm::APSInt InitVal = ECD->getInitVal(); 5914 bool FitsInInt; 5915 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5916 FitsInInt = InitVal.getActiveBits() < IntWidth; 5917 else 5918 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5919 5920 // If it fits into an integer type, force it. Otherwise force it to match 5921 // the enum decl type. 5922 QualType NewTy; 5923 unsigned NewWidth; 5924 bool NewSign; 5925 if (FitsInInt) { 5926 NewTy = Context.IntTy; 5927 NewWidth = IntWidth; 5928 NewSign = true; 5929 } else if (ECD->getType() == BestType) { 5930 // Already the right type! 5931 if (getLangOptions().CPlusPlus) 5932 // C++ [dcl.enum]p4: Following the closing brace of an 5933 // enum-specifier, each enumerator has the type of its 5934 // enumeration. 5935 ECD->setType(EnumType); 5936 continue; 5937 } else { 5938 NewTy = BestType; 5939 NewWidth = BestWidth; 5940 NewSign = BestType->isSignedIntegerType(); 5941 } 5942 5943 // Adjust the APSInt value. 5944 InitVal.extOrTrunc(NewWidth); 5945 InitVal.setIsSigned(NewSign); 5946 ECD->setInitVal(InitVal); 5947 5948 // Adjust the Expr initializer and type. 5949 if (ECD->getInitExpr()) 5950 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5951 CastExpr::CK_IntegralCast, 5952 ECD->getInitExpr(), 5953 /*isLvalue=*/false)); 5954 if (getLangOptions().CPlusPlus) 5955 // C++ [dcl.enum]p4: Following the closing brace of an 5956 // enum-specifier, each enumerator has the type of its 5957 // enumeration. 5958 ECD->setType(EnumType); 5959 else 5960 ECD->setType(NewTy); 5961 } 5962 5963 Enum->completeDefinition(Context, BestType, BestPromotionType); 5964} 5965 5966Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5967 ExprArg expr) { 5968 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5969 5970 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5971 Loc, AsmString); 5972 CurContext->addDecl(New); 5973 return DeclPtrTy::make(New); 5974} 5975 5976void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5977 SourceLocation PragmaLoc, 5978 SourceLocation NameLoc) { 5979 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5980 5981 if (PrevDecl) { 5982 PrevDecl->addAttr(::new (Context) WeakAttr()); 5983 } else { 5984 (void)WeakUndeclaredIdentifiers.insert( 5985 std::pair<IdentifierInfo*,WeakInfo> 5986 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5987 } 5988} 5989 5990void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5991 IdentifierInfo* AliasName, 5992 SourceLocation PragmaLoc, 5993 SourceLocation NameLoc, 5994 SourceLocation AliasNameLoc) { 5995 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5996 WeakInfo W = WeakInfo(Name, NameLoc); 5997 5998 if (PrevDecl) { 5999 if (!PrevDecl->hasAttr<AliasAttr>()) 6000 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6001 DeclApplyPragmaWeak(TUScope, ND, W); 6002 } else { 6003 (void)WeakUndeclaredIdentifiers.insert( 6004 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6005 } 6006} 6007