SemaDecl.cpp revision 29a7f3342c3c6dd15d914c61ae22246c36d51ce7
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInit.h" 16#include "Lookup.h" 17#include "clang/AST/APValue.h" 18#include "clang/AST/ASTConsumer.h" 19#include "clang/AST/ASTContext.h" 20#include "clang/Analysis/CFG.h" 21#include "clang/AST/CXXInheritance.h" 22#include "clang/AST/DeclObjC.h" 23#include "clang/AST/DeclTemplate.h" 24#include "clang/AST/ExprCXX.h" 25#include "clang/AST/StmtCXX.h" 26#include "clang/AST/StmtObjC.h" 27#include "clang/Parse/DeclSpec.h" 28#include "clang/Parse/ParseDiagnostic.h" 29#include "clang/Parse/Template.h" 30#include "clang/Basic/PartialDiagnostic.h" 31#include "clang/Basic/SourceManager.h" 32#include "clang/Basic/TargetInfo.h" 33// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 34#include "clang/Lex/Preprocessor.h" 35#include "clang/Lex/HeaderSearch.h" 36#include "llvm/ADT/BitVector.h" 37#include "llvm/ADT/STLExtras.h" 38#include <algorithm> 39#include <cstring> 40#include <functional> 41#include <queue> 42using namespace clang; 43 44/// getDeclName - Return a pretty name for the specified decl if possible, or 45/// an empty string if not. This is used for pretty crash reporting. 46std::string Sema::getDeclName(DeclPtrTy d) { 47 Decl *D = d.getAs<Decl>(); 48 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 49 return DN->getQualifiedNameAsString(); 50 return ""; 51} 52 53Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 54 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 55} 56 57/// \brief If the identifier refers to a type name within this scope, 58/// return the declaration of that type. 59/// 60/// This routine performs ordinary name lookup of the identifier II 61/// within the given scope, with optional C++ scope specifier SS, to 62/// determine whether the name refers to a type. If so, returns an 63/// opaque pointer (actually a QualType) corresponding to that 64/// type. Otherwise, returns NULL. 65/// 66/// If name lookup results in an ambiguity, this routine will complain 67/// and then return NULL. 68Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 69 Scope *S, const CXXScopeSpec *SS, 70 bool isClassName, 71 TypeTy *ObjectTypePtr) { 72 // Determine where we will perform name lookup. 73 DeclContext *LookupCtx = 0; 74 if (ObjectTypePtr) { 75 QualType ObjectType = QualType::getFromOpaquePtr(ObjectTypePtr); 76 if (ObjectType->isRecordType()) 77 LookupCtx = computeDeclContext(ObjectType); 78 } else if (SS && SS->isSet()) { 79 LookupCtx = computeDeclContext(*SS, false); 80 81 if (!LookupCtx) { 82 if (isDependentScopeSpecifier(*SS)) { 83 // C++ [temp.res]p3: 84 // A qualified-id that refers to a type and in which the 85 // nested-name-specifier depends on a template-parameter (14.6.2) 86 // shall be prefixed by the keyword typename to indicate that the 87 // qualified-id denotes a type, forming an 88 // elaborated-type-specifier (7.1.5.3). 89 // 90 // We therefore do not perform any name lookup if the result would 91 // refer to a member of an unknown specialization. 92 if (!isClassName) 93 return 0; 94 95 // We know from the grammar that this name refers to a type, so build a 96 // TypenameType node to describe the type. 97 // FIXME: Record somewhere that this TypenameType node has no "typename" 98 // keyword associated with it. 99 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 100 II, SS->getRange()).getAsOpaquePtr(); 101 } 102 103 return 0; 104 } 105 106 if (!LookupCtx->isDependentContext() && RequireCompleteDeclContext(*SS)) 107 return 0; 108 } 109 110 LookupResult Result(*this, &II, NameLoc, LookupOrdinaryName); 111 if (LookupCtx) { 112 // Perform "qualified" name lookup into the declaration context we 113 // computed, which is either the type of the base of a member access 114 // expression or the declaration context associated with a prior 115 // nested-name-specifier. 116 LookupQualifiedName(Result, LookupCtx); 117 118 if (ObjectTypePtr && Result.empty()) { 119 // C++ [basic.lookup.classref]p3: 120 // If the unqualified-id is ~type-name, the type-name is looked up 121 // in the context of the entire postfix-expression. If the type T of 122 // the object expression is of a class type C, the type-name is also 123 // looked up in the scope of class C. At least one of the lookups shall 124 // find a name that refers to (possibly cv-qualified) T. 125 LookupName(Result, S); 126 } 127 } else { 128 // Perform unqualified name lookup. 129 LookupName(Result, S); 130 } 131 132 NamedDecl *IIDecl = 0; 133 switch (Result.getResultKind()) { 134 case LookupResult::NotFound: 135 case LookupResult::FoundOverloaded: 136 case LookupResult::FoundUnresolvedValue: 137 return 0; 138 139 case LookupResult::Ambiguous: 140 // Recover from type-hiding ambiguities by hiding the type. We'll 141 // do the lookup again when looking for an object, and we can 142 // diagnose the error then. If we don't do this, then the error 143 // about hiding the type will be immediately followed by an error 144 // that only makes sense if the identifier was treated like a type. 145 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 146 Result.suppressDiagnostics(); 147 return 0; 148 } 149 150 // Look to see if we have a type anywhere in the list of results. 151 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 152 Res != ResEnd; ++Res) { 153 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 154 if (!IIDecl || 155 (*Res)->getLocation().getRawEncoding() < 156 IIDecl->getLocation().getRawEncoding()) 157 IIDecl = *Res; 158 } 159 } 160 161 if (!IIDecl) { 162 // None of the entities we found is a type, so there is no way 163 // to even assume that the result is a type. In this case, don't 164 // complain about the ambiguity. The parser will either try to 165 // perform this lookup again (e.g., as an object name), which 166 // will produce the ambiguity, or will complain that it expected 167 // a type name. 168 Result.suppressDiagnostics(); 169 return 0; 170 } 171 172 // We found a type within the ambiguous lookup; diagnose the 173 // ambiguity and then return that type. This might be the right 174 // answer, or it might not be, but it suppresses any attempt to 175 // perform the name lookup again. 176 break; 177 178 case LookupResult::Found: 179 IIDecl = Result.getFoundDecl(); 180 break; 181 } 182 183 assert(IIDecl && "Didn't find decl"); 184 185 QualType T; 186 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 187 DiagnoseUseOfDecl(IIDecl, NameLoc); 188 189 // C++ [temp.local]p2: 190 // Within the scope of a class template specialization or 191 // partial specialization, when the injected-class-name is 192 // not followed by a <, it is equivalent to the 193 // injected-class-name followed by the template-argument s 194 // of the class template specialization or partial 195 // specialization enclosed in <>. 196 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 197 if (RD->isInjectedClassName()) 198 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 199 T = Template->getInjectedClassNameType(Context); 200 201 if (T.isNull()) 202 T = Context.getTypeDeclType(TD); 203 204 if (SS) 205 T = getQualifiedNameType(*SS, T); 206 207 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 208 T = Context.getObjCInterfaceType(IDecl); 209 } else if (UnresolvedUsingTypenameDecl *UUDecl = 210 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 211 // FIXME: preserve source structure information. 212 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 213 } else { 214 // If it's not plausibly a type, suppress diagnostics. 215 Result.suppressDiagnostics(); 216 return 0; 217 } 218 219 return T.getAsOpaquePtr(); 220} 221 222/// isTagName() - This method is called *for error recovery purposes only* 223/// to determine if the specified name is a valid tag name ("struct foo"). If 224/// so, this returns the TST for the tag corresponding to it (TST_enum, 225/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 226/// where the user forgot to specify the tag. 227DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 228 // Do a tag name lookup in this scope. 229 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 230 LookupName(R, S, false); 231 R.suppressDiagnostics(); 232 if (R.getResultKind() == LookupResult::Found) 233 if (const TagDecl *TD = R.getAsSingle<TagDecl>()) { 234 switch (TD->getTagKind()) { 235 case TagDecl::TK_struct: return DeclSpec::TST_struct; 236 case TagDecl::TK_union: return DeclSpec::TST_union; 237 case TagDecl::TK_class: return DeclSpec::TST_class; 238 case TagDecl::TK_enum: return DeclSpec::TST_enum; 239 } 240 } 241 242 return DeclSpec::TST_unspecified; 243} 244 245bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 246 SourceLocation IILoc, 247 Scope *S, 248 const CXXScopeSpec *SS, 249 TypeTy *&SuggestedType) { 250 // We don't have anything to suggest (yet). 251 SuggestedType = 0; 252 253 // FIXME: Should we move the logic that tries to recover from a missing tag 254 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 255 256 if (!SS) 257 Diag(IILoc, diag::err_unknown_typename) << &II; 258 else if (DeclContext *DC = computeDeclContext(*SS, false)) 259 Diag(IILoc, diag::err_typename_nested_not_found) 260 << &II << DC << SS->getRange(); 261 else if (isDependentScopeSpecifier(*SS)) { 262 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 263 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 264 << SourceRange(SS->getRange().getBegin(), IILoc) 265 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 266 "typename "); 267 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 268 } else { 269 assert(SS && SS->isInvalid() && 270 "Invalid scope specifier has already been diagnosed"); 271 } 272 273 return true; 274} 275 276// Determines the context to return to after temporarily entering a 277// context. This depends in an unnecessarily complicated way on the 278// exact ordering of callbacks from the parser. 279DeclContext *Sema::getContainingDC(DeclContext *DC) { 280 281 // Functions defined inline within classes aren't parsed until we've 282 // finished parsing the top-level class, so the top-level class is 283 // the context we'll need to return to. 284 if (isa<FunctionDecl>(DC)) { 285 DC = DC->getLexicalParent(); 286 287 // A function not defined within a class will always return to its 288 // lexical context. 289 if (!isa<CXXRecordDecl>(DC)) 290 return DC; 291 292 // A C++ inline method/friend is parsed *after* the topmost class 293 // it was declared in is fully parsed ("complete"); the topmost 294 // class is the context we need to return to. 295 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 296 DC = RD; 297 298 // Return the declaration context of the topmost class the inline method is 299 // declared in. 300 return DC; 301 } 302 303 if (isa<ObjCMethodDecl>(DC)) 304 return Context.getTranslationUnitDecl(); 305 306 return DC->getLexicalParent(); 307} 308 309void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 310 assert(getContainingDC(DC) == CurContext && 311 "The next DeclContext should be lexically contained in the current one."); 312 CurContext = DC; 313 S->setEntity(DC); 314} 315 316void Sema::PopDeclContext() { 317 assert(CurContext && "DeclContext imbalance!"); 318 319 CurContext = getContainingDC(CurContext); 320} 321 322/// EnterDeclaratorContext - Used when we must lookup names in the context 323/// of a declarator's nested name specifier. 324void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 325 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 326 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 327 CurContext = DC; 328 assert(CurContext && "No context?"); 329 S->setEntity(CurContext); 330} 331 332void Sema::ExitDeclaratorContext(Scope *S) { 333 S->setEntity(PreDeclaratorDC); 334 PreDeclaratorDC = 0; 335 336 // Reset CurContext to the nearest enclosing context. 337 while (!S->getEntity() && S->getParent()) 338 S = S->getParent(); 339 CurContext = static_cast<DeclContext*>(S->getEntity()); 340 assert(CurContext && "No context?"); 341} 342 343/// \brief Determine whether we allow overloading of the function 344/// PrevDecl with another declaration. 345/// 346/// This routine determines whether overloading is possible, not 347/// whether some new function is actually an overload. It will return 348/// true in C++ (where we can always provide overloads) or, as an 349/// extension, in C when the previous function is already an 350/// overloaded function declaration or has the "overloadable" 351/// attribute. 352static bool AllowOverloadingOfFunction(LookupResult &Previous, 353 ASTContext &Context) { 354 if (Context.getLangOptions().CPlusPlus) 355 return true; 356 357 if (Previous.getResultKind() == LookupResult::FoundOverloaded) 358 return true; 359 360 return (Previous.getResultKind() == LookupResult::Found 361 && Previous.getFoundDecl()->hasAttr<OverloadableAttr>()); 362} 363 364/// Add this decl to the scope shadowed decl chains. 365void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 366 // Move up the scope chain until we find the nearest enclosing 367 // non-transparent context. The declaration will be introduced into this 368 // scope. 369 while (S->getEntity() && 370 ((DeclContext *)S->getEntity())->isTransparentContext()) 371 S = S->getParent(); 372 373 // Add scoped declarations into their context, so that they can be 374 // found later. Declarations without a context won't be inserted 375 // into any context. 376 if (AddToContext) 377 CurContext->addDecl(D); 378 379 // Out-of-line function and variable definitions should not be pushed into 380 // scope. 381 if ((isa<FunctionTemplateDecl>(D) && 382 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 383 (isa<FunctionDecl>(D) && 384 (cast<FunctionDecl>(D)->isFunctionTemplateSpecialization() || 385 cast<FunctionDecl>(D)->isOutOfLine())) || 386 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 387 return; 388 389 // If this replaces anything in the current scope, 390 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 391 IEnd = IdResolver.end(); 392 for (; I != IEnd; ++I) { 393 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 394 S->RemoveDecl(DeclPtrTy::make(*I)); 395 IdResolver.RemoveDecl(*I); 396 397 // Should only need to replace one decl. 398 break; 399 } 400 } 401 402 S->AddDecl(DeclPtrTy::make(D)); 403 IdResolver.AddDecl(D); 404} 405 406bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 407 return IdResolver.isDeclInScope(D, Ctx, Context, S); 408} 409 410static bool isOutOfScopePreviousDeclaration(NamedDecl *, 411 DeclContext*, 412 ASTContext&); 413 414/// Filters out lookup results that don't fall within the given scope 415/// as determined by isDeclInScope. 416static void FilterLookupForScope(Sema &SemaRef, LookupResult &R, 417 DeclContext *Ctx, Scope *S, 418 bool ConsiderLinkage) { 419 LookupResult::Filter F = R.makeFilter(); 420 while (F.hasNext()) { 421 NamedDecl *D = F.next(); 422 423 if (SemaRef.isDeclInScope(D, Ctx, S)) 424 continue; 425 426 if (ConsiderLinkage && 427 isOutOfScopePreviousDeclaration(D, Ctx, SemaRef.Context)) 428 continue; 429 430 F.erase(); 431 } 432 433 F.done(); 434} 435 436static bool isUsingDecl(NamedDecl *D) { 437 return isa<UsingShadowDecl>(D) || 438 isa<UnresolvedUsingTypenameDecl>(D) || 439 isa<UnresolvedUsingValueDecl>(D); 440} 441 442/// Removes using shadow declarations from the lookup results. 443static void RemoveUsingDecls(LookupResult &R) { 444 LookupResult::Filter F = R.makeFilter(); 445 while (F.hasNext()) 446 if (isUsingDecl(F.next())) 447 F.erase(); 448 449 F.done(); 450} 451 452static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 453 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 454 return false; 455 456 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 457 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 458 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 459 if (!RD->hasTrivialConstructor()) 460 return false; 461 if (!RD->hasTrivialDestructor()) 462 return false; 463 } 464 } 465 } 466 467 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 468 !isa<ImplicitParamDecl>(D) && 469 D->getDeclContext()->isFunctionOrMethod()); 470} 471 472void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 473 if (S->decl_empty()) return; 474 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 475 "Scope shouldn't contain decls!"); 476 477 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 478 I != E; ++I) { 479 Decl *TmpD = (*I).getAs<Decl>(); 480 assert(TmpD && "This decl didn't get pushed??"); 481 482 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 483 NamedDecl *D = cast<NamedDecl>(TmpD); 484 485 if (!D->getDeclName()) continue; 486 487 // Diagnose unused variables in this scope. 488 if (ShouldDiagnoseUnusedDecl(D)) 489 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 490 491 // Remove this name from our lexical scope. 492 IdResolver.RemoveDecl(D); 493 } 494} 495 496/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 497/// return 0 if one not found. 498ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 499 // The third "scope" argument is 0 since we aren't enabling lazy built-in 500 // creation from this context. 501 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 502 503 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 504} 505 506/// getNonFieldDeclScope - Retrieves the innermost scope, starting 507/// from S, where a non-field would be declared. This routine copes 508/// with the difference between C and C++ scoping rules in structs and 509/// unions. For example, the following code is well-formed in C but 510/// ill-formed in C++: 511/// @code 512/// struct S6 { 513/// enum { BAR } e; 514/// }; 515/// 516/// void test_S6() { 517/// struct S6 a; 518/// a.e = BAR; 519/// } 520/// @endcode 521/// For the declaration of BAR, this routine will return a different 522/// scope. The scope S will be the scope of the unnamed enumeration 523/// within S6. In C++, this routine will return the scope associated 524/// with S6, because the enumeration's scope is a transparent 525/// context but structures can contain non-field names. In C, this 526/// routine will return the translation unit scope, since the 527/// enumeration's scope is a transparent context and structures cannot 528/// contain non-field names. 529Scope *Sema::getNonFieldDeclScope(Scope *S) { 530 while (((S->getFlags() & Scope::DeclScope) == 0) || 531 (S->getEntity() && 532 ((DeclContext *)S->getEntity())->isTransparentContext()) || 533 (S->isClassScope() && !getLangOptions().CPlusPlus)) 534 S = S->getParent(); 535 return S; 536} 537 538void Sema::InitBuiltinVaListType() { 539 if (!Context.getBuiltinVaListType().isNull()) 540 return; 541 542 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 543 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 544 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 545 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 546} 547 548/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 549/// file scope. lazily create a decl for it. ForRedeclaration is true 550/// if we're creating this built-in in anticipation of redeclaring the 551/// built-in. 552NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 553 Scope *S, bool ForRedeclaration, 554 SourceLocation Loc) { 555 Builtin::ID BID = (Builtin::ID)bid; 556 557 if (Context.BuiltinInfo.hasVAListUse(BID)) 558 InitBuiltinVaListType(); 559 560 ASTContext::GetBuiltinTypeError Error; 561 QualType R = Context.GetBuiltinType(BID, Error); 562 switch (Error) { 563 case ASTContext::GE_None: 564 // Okay 565 break; 566 567 case ASTContext::GE_Missing_stdio: 568 if (ForRedeclaration) 569 Diag(Loc, diag::err_implicit_decl_requires_stdio) 570 << Context.BuiltinInfo.GetName(BID); 571 return 0; 572 573 case ASTContext::GE_Missing_setjmp: 574 if (ForRedeclaration) 575 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 576 << Context.BuiltinInfo.GetName(BID); 577 return 0; 578 } 579 580 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 581 Diag(Loc, diag::ext_implicit_lib_function_decl) 582 << Context.BuiltinInfo.GetName(BID) 583 << R; 584 if (Context.BuiltinInfo.getHeaderName(BID) && 585 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 586 != Diagnostic::Ignored) 587 Diag(Loc, diag::note_please_include_header) 588 << Context.BuiltinInfo.getHeaderName(BID) 589 << Context.BuiltinInfo.GetName(BID); 590 } 591 592 FunctionDecl *New = FunctionDecl::Create(Context, 593 Context.getTranslationUnitDecl(), 594 Loc, II, R, /*TInfo=*/0, 595 FunctionDecl::Extern, false, 596 /*hasPrototype=*/true); 597 New->setImplicit(); 598 599 // Create Decl objects for each parameter, adding them to the 600 // FunctionDecl. 601 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 602 llvm::SmallVector<ParmVarDecl*, 16> Params; 603 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 604 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 605 FT->getArgType(i), /*TInfo=*/0, 606 VarDecl::None, 0)); 607 New->setParams(Context, Params.data(), Params.size()); 608 } 609 610 AddKnownFunctionAttributes(New); 611 612 // TUScope is the translation-unit scope to insert this function into. 613 // FIXME: This is hideous. We need to teach PushOnScopeChains to 614 // relate Scopes to DeclContexts, and probably eliminate CurContext 615 // entirely, but we're not there yet. 616 DeclContext *SavedContext = CurContext; 617 CurContext = Context.getTranslationUnitDecl(); 618 PushOnScopeChains(New, TUScope); 619 CurContext = SavedContext; 620 return New; 621} 622 623/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 624/// same name and scope as a previous declaration 'Old'. Figure out 625/// how to resolve this situation, merging decls or emitting 626/// diagnostics as appropriate. If there was an error, set New to be invalid. 627/// 628void Sema::MergeTypeDefDecl(TypedefDecl *New, LookupResult &OldDecls) { 629 // If the new decl is known invalid already, don't bother doing any 630 // merging checks. 631 if (New->isInvalidDecl()) return; 632 633 // Allow multiple definitions for ObjC built-in typedefs. 634 // FIXME: Verify the underlying types are equivalent! 635 if (getLangOptions().ObjC1) { 636 const IdentifierInfo *TypeID = New->getIdentifier(); 637 switch (TypeID->getLength()) { 638 default: break; 639 case 2: 640 if (!TypeID->isStr("id")) 641 break; 642 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 643 // Install the built-in type for 'id', ignoring the current definition. 644 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 645 return; 646 case 5: 647 if (!TypeID->isStr("Class")) 648 break; 649 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 650 // Install the built-in type for 'Class', ignoring the current definition. 651 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 652 return; 653 case 3: 654 if (!TypeID->isStr("SEL")) 655 break; 656 Context.ObjCSelRedefinitionType = New->getUnderlyingType(); 657 // Install the built-in type for 'SEL', ignoring the current definition. 658 New->setTypeForDecl(Context.getObjCSelType().getTypePtr()); 659 return; 660 case 8: 661 if (!TypeID->isStr("Protocol")) 662 break; 663 Context.setObjCProtoType(New->getUnderlyingType()); 664 return; 665 } 666 // Fall through - the typedef name was not a builtin type. 667 } 668 669 // Verify the old decl was also a type. 670 TypeDecl *Old = 0; 671 if (!OldDecls.isSingleResult() || 672 !(Old = dyn_cast<TypeDecl>(OldDecls.getFoundDecl()))) { 673 Diag(New->getLocation(), diag::err_redefinition_different_kind) 674 << New->getDeclName(); 675 676 NamedDecl *OldD = OldDecls.getRepresentativeDecl(); 677 if (OldD->getLocation().isValid()) 678 Diag(OldD->getLocation(), diag::note_previous_definition); 679 680 return New->setInvalidDecl(); 681 } 682 683 // If the old declaration is invalid, just give up here. 684 if (Old->isInvalidDecl()) 685 return New->setInvalidDecl(); 686 687 // Determine the "old" type we'll use for checking and diagnostics. 688 QualType OldType; 689 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 690 OldType = OldTypedef->getUnderlyingType(); 691 else 692 OldType = Context.getTypeDeclType(Old); 693 694 // If the typedef types are not identical, reject them in all languages and 695 // with any extensions enabled. 696 697 if (OldType != New->getUnderlyingType() && 698 Context.getCanonicalType(OldType) != 699 Context.getCanonicalType(New->getUnderlyingType())) { 700 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 701 << New->getUnderlyingType() << OldType; 702 if (Old->getLocation().isValid()) 703 Diag(Old->getLocation(), diag::note_previous_definition); 704 return New->setInvalidDecl(); 705 } 706 707 if (getLangOptions().Microsoft) 708 return; 709 710 // C++ [dcl.typedef]p2: 711 // In a given non-class scope, a typedef specifier can be used to 712 // redefine the name of any type declared in that scope to refer 713 // to the type to which it already refers. 714 if (getLangOptions().CPlusPlus) { 715 if (!isa<CXXRecordDecl>(CurContext)) 716 return; 717 Diag(New->getLocation(), diag::err_redefinition) 718 << New->getDeclName(); 719 Diag(Old->getLocation(), diag::note_previous_definition); 720 return New->setInvalidDecl(); 721 } 722 723 // If we have a redefinition of a typedef in C, emit a warning. This warning 724 // is normally mapped to an error, but can be controlled with 725 // -Wtypedef-redefinition. If either the original or the redefinition is 726 // in a system header, don't emit this for compatibility with GCC. 727 if (PP.getDiagnostics().getSuppressSystemWarnings() && 728 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 729 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 730 return; 731 732 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 733 << New->getDeclName(); 734 Diag(Old->getLocation(), diag::note_previous_definition); 735 return; 736} 737 738/// DeclhasAttr - returns true if decl Declaration already has the target 739/// attribute. 740static bool 741DeclHasAttr(const Decl *decl, const Attr *target) { 742 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 743 if (attr->getKind() == target->getKind()) 744 return true; 745 746 return false; 747} 748 749/// MergeAttributes - append attributes from the Old decl to the New one. 750static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 751 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 752 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 753 Attr *NewAttr = attr->clone(C); 754 NewAttr->setInherited(true); 755 New->addAttr(NewAttr); 756 } 757 } 758} 759 760/// Used in MergeFunctionDecl to keep track of function parameters in 761/// C. 762struct GNUCompatibleParamWarning { 763 ParmVarDecl *OldParm; 764 ParmVarDecl *NewParm; 765 QualType PromotedType; 766}; 767 768 769/// getSpecialMember - get the special member enum for a method. 770static Sema::CXXSpecialMember getSpecialMember(ASTContext &Ctx, 771 const CXXMethodDecl *MD) { 772 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) { 773 if (Ctor->isDefaultConstructor()) 774 return Sema::CXXDefaultConstructor; 775 if (Ctor->isCopyConstructor(Ctx)) 776 return Sema::CXXCopyConstructor; 777 } 778 779 if (isa<CXXDestructorDecl>(MD)) 780 return Sema::CXXDestructor; 781 782 assert(MD->isCopyAssignment() && "Must have copy assignment operator"); 783 return Sema::CXXCopyAssignment; 784} 785 786/// MergeFunctionDecl - We just parsed a function 'New' from 787/// declarator D which has the same name and scope as a previous 788/// declaration 'Old'. Figure out how to resolve this situation, 789/// merging decls or emitting diagnostics as appropriate. 790/// 791/// In C++, New and Old must be declarations that are not 792/// overloaded. Use IsOverload to determine whether New and Old are 793/// overloaded, and to select the Old declaration that New should be 794/// merged with. 795/// 796/// Returns true if there was an error, false otherwise. 797bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 798 // Verify the old decl was also a function. 799 FunctionDecl *Old = 0; 800 if (FunctionTemplateDecl *OldFunctionTemplate 801 = dyn_cast<FunctionTemplateDecl>(OldD)) 802 Old = OldFunctionTemplate->getTemplatedDecl(); 803 else 804 Old = dyn_cast<FunctionDecl>(OldD); 805 if (!Old) { 806 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(OldD)) { 807 Diag(New->getLocation(), diag::err_using_decl_conflict_reverse); 808 Diag(Shadow->getTargetDecl()->getLocation(), 809 diag::note_using_decl_target); 810 Diag(Shadow->getUsingDecl()->getLocation(), 811 diag::note_using_decl) << 0; 812 return true; 813 } 814 815 Diag(New->getLocation(), diag::err_redefinition_different_kind) 816 << New->getDeclName(); 817 Diag(OldD->getLocation(), diag::note_previous_definition); 818 return true; 819 } 820 821 // Determine whether the previous declaration was a definition, 822 // implicit declaration, or a declaration. 823 diag::kind PrevDiag; 824 if (Old->isThisDeclarationADefinition()) 825 PrevDiag = diag::note_previous_definition; 826 else if (Old->isImplicit()) 827 PrevDiag = diag::note_previous_implicit_declaration; 828 else 829 PrevDiag = diag::note_previous_declaration; 830 831 QualType OldQType = Context.getCanonicalType(Old->getType()); 832 QualType NewQType = Context.getCanonicalType(New->getType()); 833 834 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 835 New->getStorageClass() == FunctionDecl::Static && 836 Old->getStorageClass() != FunctionDecl::Static) { 837 Diag(New->getLocation(), diag::err_static_non_static) 838 << New; 839 Diag(Old->getLocation(), PrevDiag); 840 return true; 841 } 842 843 if (getLangOptions().CPlusPlus) { 844 // (C++98 13.1p2): 845 // Certain function declarations cannot be overloaded: 846 // -- Function declarations that differ only in the return type 847 // cannot be overloaded. 848 QualType OldReturnType 849 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 850 QualType NewReturnType 851 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 852 if (OldReturnType != NewReturnType) { 853 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 854 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 855 return true; 856 } 857 858 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 859 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 860 if (OldMethod && NewMethod) { 861 if (!NewMethod->getFriendObjectKind() && 862 NewMethod->getLexicalDeclContext()->isRecord()) { 863 // -- Member function declarations with the same name and the 864 // same parameter types cannot be overloaded if any of them 865 // is a static member function declaration. 866 if (OldMethod->isStatic() || NewMethod->isStatic()) { 867 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 868 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 869 return true; 870 } 871 872 // C++ [class.mem]p1: 873 // [...] A member shall not be declared twice in the 874 // member-specification, except that a nested class or member 875 // class template can be declared and then later defined. 876 unsigned NewDiag; 877 if (isa<CXXConstructorDecl>(OldMethod)) 878 NewDiag = diag::err_constructor_redeclared; 879 else if (isa<CXXDestructorDecl>(NewMethod)) 880 NewDiag = diag::err_destructor_redeclared; 881 else if (isa<CXXConversionDecl>(NewMethod)) 882 NewDiag = diag::err_conv_function_redeclared; 883 else 884 NewDiag = diag::err_member_redeclared; 885 886 Diag(New->getLocation(), NewDiag); 887 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 888 } else { 889 if (OldMethod->isImplicit()) { 890 Diag(NewMethod->getLocation(), 891 diag::err_definition_of_implicitly_declared_member) 892 << New << getSpecialMember(Context, OldMethod); 893 894 Diag(OldMethod->getLocation(), 895 diag::note_previous_implicit_declaration); 896 return true; 897 } 898 } 899 } 900 901 // (C++98 8.3.5p3): 902 // All declarations for a function shall agree exactly in both the 903 // return type and the parameter-type-list. 904 if (OldQType == NewQType) 905 return MergeCompatibleFunctionDecls(New, Old); 906 907 // Fall through for conflicting redeclarations and redefinitions. 908 } 909 910 // C: Function types need to be compatible, not identical. This handles 911 // duplicate function decls like "void f(int); void f(enum X);" properly. 912 if (!getLangOptions().CPlusPlus && 913 Context.typesAreCompatible(OldQType, NewQType)) { 914 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 915 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 916 const FunctionProtoType *OldProto = 0; 917 if (isa<FunctionNoProtoType>(NewFuncType) && 918 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 919 // The old declaration provided a function prototype, but the 920 // new declaration does not. Merge in the prototype. 921 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 922 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 923 OldProto->arg_type_end()); 924 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 925 ParamTypes.data(), ParamTypes.size(), 926 OldProto->isVariadic(), 927 OldProto->getTypeQuals()); 928 New->setType(NewQType); 929 New->setHasInheritedPrototype(); 930 931 // Synthesize a parameter for each argument type. 932 llvm::SmallVector<ParmVarDecl*, 16> Params; 933 for (FunctionProtoType::arg_type_iterator 934 ParamType = OldProto->arg_type_begin(), 935 ParamEnd = OldProto->arg_type_end(); 936 ParamType != ParamEnd; ++ParamType) { 937 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 938 SourceLocation(), 0, 939 *ParamType, /*TInfo=*/0, 940 VarDecl::None, 0); 941 Param->setImplicit(); 942 Params.push_back(Param); 943 } 944 945 New->setParams(Context, Params.data(), Params.size()); 946 } 947 948 return MergeCompatibleFunctionDecls(New, Old); 949 } 950 951 // GNU C permits a K&R definition to follow a prototype declaration 952 // if the declared types of the parameters in the K&R definition 953 // match the types in the prototype declaration, even when the 954 // promoted types of the parameters from the K&R definition differ 955 // from the types in the prototype. GCC then keeps the types from 956 // the prototype. 957 // 958 // If a variadic prototype is followed by a non-variadic K&R definition, 959 // the K&R definition becomes variadic. This is sort of an edge case, but 960 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 961 // C99 6.9.1p8. 962 if (!getLangOptions().CPlusPlus && 963 Old->hasPrototype() && !New->hasPrototype() && 964 New->getType()->getAs<FunctionProtoType>() && 965 Old->getNumParams() == New->getNumParams()) { 966 llvm::SmallVector<QualType, 16> ArgTypes; 967 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 968 const FunctionProtoType *OldProto 969 = Old->getType()->getAs<FunctionProtoType>(); 970 const FunctionProtoType *NewProto 971 = New->getType()->getAs<FunctionProtoType>(); 972 973 // Determine whether this is the GNU C extension. 974 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 975 NewProto->getResultType()); 976 bool LooseCompatible = !MergedReturn.isNull(); 977 for (unsigned Idx = 0, End = Old->getNumParams(); 978 LooseCompatible && Idx != End; ++Idx) { 979 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 980 ParmVarDecl *NewParm = New->getParamDecl(Idx); 981 if (Context.typesAreCompatible(OldParm->getType(), 982 NewProto->getArgType(Idx))) { 983 ArgTypes.push_back(NewParm->getType()); 984 } else if (Context.typesAreCompatible(OldParm->getType(), 985 NewParm->getType())) { 986 GNUCompatibleParamWarning Warn 987 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 988 Warnings.push_back(Warn); 989 ArgTypes.push_back(NewParm->getType()); 990 } else 991 LooseCompatible = false; 992 } 993 994 if (LooseCompatible) { 995 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 996 Diag(Warnings[Warn].NewParm->getLocation(), 997 diag::ext_param_promoted_not_compatible_with_prototype) 998 << Warnings[Warn].PromotedType 999 << Warnings[Warn].OldParm->getType(); 1000 Diag(Warnings[Warn].OldParm->getLocation(), 1001 diag::note_previous_declaration); 1002 } 1003 1004 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 1005 ArgTypes.size(), 1006 OldProto->isVariadic(), 0)); 1007 return MergeCompatibleFunctionDecls(New, Old); 1008 } 1009 1010 // Fall through to diagnose conflicting types. 1011 } 1012 1013 // A function that has already been declared has been redeclared or defined 1014 // with a different type- show appropriate diagnostic 1015 if (unsigned BuiltinID = Old->getBuiltinID()) { 1016 // The user has declared a builtin function with an incompatible 1017 // signature. 1018 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 1019 // The function the user is redeclaring is a library-defined 1020 // function like 'malloc' or 'printf'. Warn about the 1021 // redeclaration, then pretend that we don't know about this 1022 // library built-in. 1023 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 1024 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 1025 << Old << Old->getType(); 1026 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 1027 Old->setInvalidDecl(); 1028 return false; 1029 } 1030 1031 PrevDiag = diag::note_previous_builtin_declaration; 1032 } 1033 1034 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 1035 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 1036 return true; 1037} 1038 1039/// \brief Completes the merge of two function declarations that are 1040/// known to be compatible. 1041/// 1042/// This routine handles the merging of attributes and other 1043/// properties of function declarations form the old declaration to 1044/// the new declaration, once we know that New is in fact a 1045/// redeclaration of Old. 1046/// 1047/// \returns false 1048bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 1049 // Merge the attributes 1050 MergeAttributes(New, Old, Context); 1051 1052 // Merge the storage class. 1053 if (Old->getStorageClass() != FunctionDecl::Extern && 1054 Old->getStorageClass() != FunctionDecl::None) 1055 New->setStorageClass(Old->getStorageClass()); 1056 1057 // Merge "pure" flag. 1058 if (Old->isPure()) 1059 New->setPure(); 1060 1061 // Merge the "deleted" flag. 1062 if (Old->isDeleted()) 1063 New->setDeleted(); 1064 1065 if (getLangOptions().CPlusPlus) 1066 return MergeCXXFunctionDecl(New, Old); 1067 1068 return false; 1069} 1070 1071/// MergeVarDecl - We just parsed a variable 'New' which has the same name 1072/// and scope as a previous declaration 'Old'. Figure out how to resolve this 1073/// situation, merging decls or emitting diagnostics as appropriate. 1074/// 1075/// Tentative definition rules (C99 6.9.2p2) are checked by 1076/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 1077/// definitions here, since the initializer hasn't been attached. 1078/// 1079void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) { 1080 // If the new decl is already invalid, don't do any other checking. 1081 if (New->isInvalidDecl()) 1082 return; 1083 1084 // Verify the old decl was also a variable. 1085 VarDecl *Old = 0; 1086 if (!Previous.isSingleResult() || 1087 !(Old = dyn_cast<VarDecl>(Previous.getFoundDecl()))) { 1088 Diag(New->getLocation(), diag::err_redefinition_different_kind) 1089 << New->getDeclName(); 1090 Diag(Previous.getRepresentativeDecl()->getLocation(), 1091 diag::note_previous_definition); 1092 return New->setInvalidDecl(); 1093 } 1094 1095 MergeAttributes(New, Old, Context); 1096 1097 // Merge the types 1098 QualType MergedT; 1099 if (getLangOptions().CPlusPlus) { 1100 if (Context.hasSameType(New->getType(), Old->getType())) 1101 MergedT = New->getType(); 1102 // C++ [basic.link]p10: 1103 // [...] the types specified by all declarations referring to a given 1104 // object or function shall be identical, except that declarations for an 1105 // array object can specify array types that differ by the presence or 1106 // absence of a major array bound (8.3.4). 1107 else if (Old->getType()->isIncompleteArrayType() && 1108 New->getType()->isArrayType()) { 1109 CanQual<ArrayType> OldArray 1110 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1111 CanQual<ArrayType> NewArray 1112 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1113 if (OldArray->getElementType() == NewArray->getElementType()) 1114 MergedT = New->getType(); 1115 } else if (Old->getType()->isArrayType() && 1116 New->getType()->isIncompleteArrayType()) { 1117 CanQual<ArrayType> OldArray 1118 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1119 CanQual<ArrayType> NewArray 1120 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1121 if (OldArray->getElementType() == NewArray->getElementType()) 1122 MergedT = Old->getType(); 1123 } 1124 } else { 1125 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1126 } 1127 if (MergedT.isNull()) { 1128 Diag(New->getLocation(), diag::err_redefinition_different_type) 1129 << New->getDeclName(); 1130 Diag(Old->getLocation(), diag::note_previous_definition); 1131 return New->setInvalidDecl(); 1132 } 1133 New->setType(MergedT); 1134 1135 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1136 if (New->getStorageClass() == VarDecl::Static && 1137 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1138 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1139 Diag(Old->getLocation(), diag::note_previous_definition); 1140 return New->setInvalidDecl(); 1141 } 1142 // C99 6.2.2p4: 1143 // For an identifier declared with the storage-class specifier 1144 // extern in a scope in which a prior declaration of that 1145 // identifier is visible,23) if the prior declaration specifies 1146 // internal or external linkage, the linkage of the identifier at 1147 // the later declaration is the same as the linkage specified at 1148 // the prior declaration. If no prior declaration is visible, or 1149 // if the prior declaration specifies no linkage, then the 1150 // identifier has external linkage. 1151 if (New->hasExternalStorage() && Old->hasLinkage()) 1152 /* Okay */; 1153 else if (New->getStorageClass() != VarDecl::Static && 1154 Old->getStorageClass() == VarDecl::Static) { 1155 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1156 Diag(Old->getLocation(), diag::note_previous_definition); 1157 return New->setInvalidDecl(); 1158 } 1159 1160 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1161 1162 // FIXME: The test for external storage here seems wrong? We still 1163 // need to check for mismatches. 1164 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1165 // Don't complain about out-of-line definitions of static members. 1166 !(Old->getLexicalDeclContext()->isRecord() && 1167 !New->getLexicalDeclContext()->isRecord())) { 1168 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1169 Diag(Old->getLocation(), diag::note_previous_definition); 1170 return New->setInvalidDecl(); 1171 } 1172 1173 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1174 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1175 Diag(Old->getLocation(), diag::note_previous_definition); 1176 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1177 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1178 Diag(Old->getLocation(), diag::note_previous_definition); 1179 } 1180 1181 // Keep a chain of previous declarations. 1182 New->setPreviousDeclaration(Old); 1183} 1184 1185/// CheckFallThrough - Check that we don't fall off the end of a 1186/// Statement that should return a value. 1187/// 1188/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1189/// MaybeFallThrough iff we might or might not fall off the end, 1190/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1191/// return. We assume NeverFallThrough iff we never fall off the end of the 1192/// statement but we may return. We assume that functions not marked noreturn 1193/// will return. 1194Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1195 // FIXME: Eventually share this CFG object when we have other warnings based 1196 // of the CFG. This can be done using AnalysisContext. 1197 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1198 1199 // FIXME: They should never return 0, fix that, delete this code. 1200 if (cfg == 0) 1201 // FIXME: This should be NeverFallThrough 1202 return NeverFallThroughOrReturn; 1203 // The CFG leaves in dead things, and we don't want to dead code paths to 1204 // confuse us, so we mark all live things first. 1205 std::queue<CFGBlock*> workq; 1206 llvm::BitVector live(cfg->getNumBlockIDs()); 1207 // Prep work queue 1208 workq.push(&cfg->getEntry()); 1209 // Solve 1210 while (!workq.empty()) { 1211 CFGBlock *item = workq.front(); 1212 workq.pop(); 1213 live.set(item->getBlockID()); 1214 for (CFGBlock::succ_iterator I=item->succ_begin(), 1215 E=item->succ_end(); 1216 I != E; 1217 ++I) { 1218 if ((*I) && !live[(*I)->getBlockID()]) { 1219 live.set((*I)->getBlockID()); 1220 workq.push(*I); 1221 } 1222 } 1223 } 1224 1225 // Now we know what is live, we check the live precessors of the exit block 1226 // and look for fall through paths, being careful to ignore normal returns, 1227 // and exceptional paths. 1228 bool HasLiveReturn = false; 1229 bool HasFakeEdge = false; 1230 bool HasPlainEdge = false; 1231 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1232 E = cfg->getExit().pred_end(); 1233 I != E; 1234 ++I) { 1235 CFGBlock& B = **I; 1236 if (!live[B.getBlockID()]) 1237 continue; 1238 if (B.size() == 0) { 1239 // A labeled empty statement, or the entry block... 1240 HasPlainEdge = true; 1241 continue; 1242 } 1243 Stmt *S = B[B.size()-1]; 1244 if (isa<ReturnStmt>(S)) { 1245 HasLiveReturn = true; 1246 continue; 1247 } 1248 if (isa<ObjCAtThrowStmt>(S)) { 1249 HasFakeEdge = true; 1250 continue; 1251 } 1252 if (isa<CXXThrowExpr>(S)) { 1253 HasFakeEdge = true; 1254 continue; 1255 } 1256 bool NoReturnEdge = false; 1257 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1258 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1259 if (CEE->getType().getNoReturnAttr()) { 1260 NoReturnEdge = true; 1261 HasFakeEdge = true; 1262 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1263 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1264 if (FD->hasAttr<NoReturnAttr>()) { 1265 NoReturnEdge = true; 1266 HasFakeEdge = true; 1267 } 1268 } 1269 } 1270 } 1271 // FIXME: Add noreturn message sends. 1272 if (NoReturnEdge == false) 1273 HasPlainEdge = true; 1274 } 1275 if (!HasPlainEdge) { 1276 if (HasLiveReturn) 1277 return NeverFallThrough; 1278 return NeverFallThroughOrReturn; 1279 } 1280 if (HasFakeEdge || HasLiveReturn) 1281 return MaybeFallThrough; 1282 // This says AlwaysFallThrough for calls to functions that are not marked 1283 // noreturn, that don't return. If people would like this warning to be more 1284 // accurate, such functions should be marked as noreturn. 1285 return AlwaysFallThrough; 1286} 1287 1288/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1289/// function that should return a value. Check that we don't fall off the end 1290/// of a noreturn function. We assume that functions and blocks not marked 1291/// noreturn will return. 1292void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1293 // FIXME: Would be nice if we had a better way to control cascading errors, 1294 // but for now, avoid them. The problem is that when Parse sees: 1295 // int foo() { return a; } 1296 // The return is eaten and the Sema code sees just: 1297 // int foo() { } 1298 // which this code would then warn about. 1299 if (getDiagnostics().hasErrorOccurred()) 1300 return; 1301 1302 bool ReturnsVoid = false; 1303 bool HasNoReturn = false; 1304 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1305 // If the result type of the function is a dependent type, we don't know 1306 // whether it will be void or not, so don't 1307 if (FD->getResultType()->isDependentType()) 1308 return; 1309 if (FD->getResultType()->isVoidType()) 1310 ReturnsVoid = true; 1311 if (FD->hasAttr<NoReturnAttr>()) 1312 HasNoReturn = true; 1313 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1314 if (MD->getResultType()->isVoidType()) 1315 ReturnsVoid = true; 1316 if (MD->hasAttr<NoReturnAttr>()) 1317 HasNoReturn = true; 1318 } 1319 1320 // Short circuit for compilation speed. 1321 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1322 == Diagnostic::Ignored || ReturnsVoid) 1323 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1324 == Diagnostic::Ignored || !HasNoReturn) 1325 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1326 == Diagnostic::Ignored || !ReturnsVoid)) 1327 return; 1328 // FIXME: Function try block 1329 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1330 switch (CheckFallThrough(Body)) { 1331 case MaybeFallThrough: 1332 if (HasNoReturn) 1333 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1334 else if (!ReturnsVoid) 1335 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1336 break; 1337 case AlwaysFallThrough: 1338 if (HasNoReturn) 1339 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1340 else if (!ReturnsVoid) 1341 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1342 break; 1343 case NeverFallThroughOrReturn: 1344 if (ReturnsVoid && !HasNoReturn) 1345 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1346 break; 1347 case NeverFallThrough: 1348 break; 1349 } 1350 } 1351} 1352 1353/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1354/// that should return a value. Check that we don't fall off the end of a 1355/// noreturn block. We assume that functions and blocks not marked noreturn 1356/// will return. 1357void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1358 // FIXME: Would be nice if we had a better way to control cascading errors, 1359 // but for now, avoid them. The problem is that when Parse sees: 1360 // int foo() { return a; } 1361 // The return is eaten and the Sema code sees just: 1362 // int foo() { } 1363 // which this code would then warn about. 1364 if (getDiagnostics().hasErrorOccurred()) 1365 return; 1366 bool ReturnsVoid = false; 1367 bool HasNoReturn = false; 1368 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1369 if (FT->getResultType()->isVoidType()) 1370 ReturnsVoid = true; 1371 if (FT->getNoReturnAttr()) 1372 HasNoReturn = true; 1373 } 1374 1375 // Short circuit for compilation speed. 1376 if (ReturnsVoid 1377 && !HasNoReturn 1378 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1379 == Diagnostic::Ignored || !ReturnsVoid)) 1380 return; 1381 // FIXME: Funtion try block 1382 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1383 switch (CheckFallThrough(Body)) { 1384 case MaybeFallThrough: 1385 if (HasNoReturn) 1386 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1387 else if (!ReturnsVoid) 1388 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1389 break; 1390 case AlwaysFallThrough: 1391 if (HasNoReturn) 1392 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1393 else if (!ReturnsVoid) 1394 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1395 break; 1396 case NeverFallThroughOrReturn: 1397 if (ReturnsVoid) 1398 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1399 break; 1400 case NeverFallThrough: 1401 break; 1402 } 1403 } 1404} 1405 1406/// CheckParmsForFunctionDef - Check that the parameters of the given 1407/// function are appropriate for the definition of a function. This 1408/// takes care of any checks that cannot be performed on the 1409/// declaration itself, e.g., that the types of each of the function 1410/// parameters are complete. 1411bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1412 bool HasInvalidParm = false; 1413 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1414 ParmVarDecl *Param = FD->getParamDecl(p); 1415 1416 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1417 // function declarator that is part of a function definition of 1418 // that function shall not have incomplete type. 1419 // 1420 // This is also C++ [dcl.fct]p6. 1421 if (!Param->isInvalidDecl() && 1422 RequireCompleteType(Param->getLocation(), Param->getType(), 1423 diag::err_typecheck_decl_incomplete_type)) { 1424 Param->setInvalidDecl(); 1425 HasInvalidParm = true; 1426 } 1427 1428 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1429 // declaration of each parameter shall include an identifier. 1430 if (Param->getIdentifier() == 0 && 1431 !Param->isImplicit() && 1432 !getLangOptions().CPlusPlus) 1433 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1434 } 1435 1436 return HasInvalidParm; 1437} 1438 1439/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1440/// no declarator (e.g. "struct foo;") is parsed. 1441Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1442 // FIXME: Error on auto/register at file scope 1443 // FIXME: Error on inline/virtual/explicit 1444 // FIXME: Error on invalid restrict 1445 // FIXME: Warn on useless __thread 1446 // FIXME: Warn on useless const/volatile 1447 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1448 // FIXME: Warn on useless attributes 1449 Decl *TagD = 0; 1450 TagDecl *Tag = 0; 1451 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1452 DS.getTypeSpecType() == DeclSpec::TST_struct || 1453 DS.getTypeSpecType() == DeclSpec::TST_union || 1454 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1455 TagD = static_cast<Decl *>(DS.getTypeRep()); 1456 1457 if (!TagD) // We probably had an error 1458 return DeclPtrTy(); 1459 1460 // Note that the above type specs guarantee that the 1461 // type rep is a Decl, whereas in many of the others 1462 // it's a Type. 1463 Tag = dyn_cast<TagDecl>(TagD); 1464 } 1465 1466 if (DS.isFriendSpecified()) { 1467 // If we're dealing with a class template decl, assume that the 1468 // template routines are handling it. 1469 if (TagD && isa<ClassTemplateDecl>(TagD)) 1470 return DeclPtrTy(); 1471 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1472 } 1473 1474 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1475 // If there are attributes in the DeclSpec, apply them to the record. 1476 if (const AttributeList *AL = DS.getAttributes()) 1477 ProcessDeclAttributeList(S, Record, AL); 1478 1479 if (!Record->getDeclName() && Record->isDefinition() && 1480 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1481 if (getLangOptions().CPlusPlus || 1482 Record->getDeclContext()->isRecord()) 1483 return BuildAnonymousStructOrUnion(S, DS, Record); 1484 1485 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1486 << DS.getSourceRange(); 1487 } 1488 1489 // Microsoft allows unnamed struct/union fields. Don't complain 1490 // about them. 1491 // FIXME: Should we support Microsoft's extensions in this area? 1492 if (Record->getDeclName() && getLangOptions().Microsoft) 1493 return DeclPtrTy::make(Tag); 1494 } 1495 1496 if (!DS.isMissingDeclaratorOk() && 1497 DS.getTypeSpecType() != DeclSpec::TST_error) { 1498 // Warn about typedefs of enums without names, since this is an 1499 // extension in both Microsoft an GNU. 1500 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1501 Tag && isa<EnumDecl>(Tag)) { 1502 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1503 << DS.getSourceRange(); 1504 return DeclPtrTy::make(Tag); 1505 } 1506 1507 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1508 << DS.getSourceRange(); 1509 return DeclPtrTy(); 1510 } 1511 1512 return DeclPtrTy::make(Tag); 1513} 1514 1515/// We are trying to introduce the given name into the given context; 1516/// check if there's an existing declaration that can't be overloaded. 1517/// 1518/// \return true if this is a forbidden redeclaration 1519bool Sema::CheckRedeclaration(DeclContext *DC, 1520 DeclarationName Name, 1521 SourceLocation NameLoc, 1522 unsigned diagnostic) { 1523 LookupResult R(*this, Name, NameLoc, LookupOrdinaryName, 1524 ForRedeclaration); 1525 LookupQualifiedName(R, DC); 1526 1527 if (R.empty()) return false; 1528 1529 if (R.getResultKind() == LookupResult::Found && 1530 isa<TagDecl>(R.getFoundDecl())) 1531 return false; 1532 1533 // Pick a representative declaration. 1534 NamedDecl *PrevDecl = (*R.begin())->getUnderlyingDecl(); 1535 1536 Diag(NameLoc, diagnostic) << Name; 1537 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1538 1539 return true; 1540} 1541 1542/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1543/// anonymous struct or union AnonRecord into the owning context Owner 1544/// and scope S. This routine will be invoked just after we realize 1545/// that an unnamed union or struct is actually an anonymous union or 1546/// struct, e.g., 1547/// 1548/// @code 1549/// union { 1550/// int i; 1551/// float f; 1552/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1553/// // f into the surrounding scope.x 1554/// @endcode 1555/// 1556/// This routine is recursive, injecting the names of nested anonymous 1557/// structs/unions into the owning context and scope as well. 1558bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1559 RecordDecl *AnonRecord) { 1560 unsigned diagKind 1561 = AnonRecord->isUnion() ? diag::err_anonymous_union_member_redecl 1562 : diag::err_anonymous_struct_member_redecl; 1563 1564 bool Invalid = false; 1565 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1566 FEnd = AnonRecord->field_end(); 1567 F != FEnd; ++F) { 1568 if ((*F)->getDeclName()) { 1569 if (CheckRedeclaration(Owner, (*F)->getDeclName(), 1570 (*F)->getLocation(), diagKind)) { 1571 // C++ [class.union]p2: 1572 // The names of the members of an anonymous union shall be 1573 // distinct from the names of any other entity in the 1574 // scope in which the anonymous union is declared. 1575 Invalid = true; 1576 } else { 1577 // C++ [class.union]p2: 1578 // For the purpose of name lookup, after the anonymous union 1579 // definition, the members of the anonymous union are 1580 // considered to have been defined in the scope in which the 1581 // anonymous union is declared. 1582 Owner->makeDeclVisibleInContext(*F); 1583 S->AddDecl(DeclPtrTy::make(*F)); 1584 IdResolver.AddDecl(*F); 1585 } 1586 } else if (const RecordType *InnerRecordType 1587 = (*F)->getType()->getAs<RecordType>()) { 1588 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1589 if (InnerRecord->isAnonymousStructOrUnion()) 1590 Invalid = Invalid || 1591 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1592 } 1593 } 1594 1595 return Invalid; 1596} 1597 1598/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1599/// anonymous structure or union. Anonymous unions are a C++ feature 1600/// (C++ [class.union]) and a GNU C extension; anonymous structures 1601/// are a GNU C and GNU C++ extension. 1602Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1603 RecordDecl *Record) { 1604 DeclContext *Owner = Record->getDeclContext(); 1605 1606 // Diagnose whether this anonymous struct/union is an extension. 1607 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1608 Diag(Record->getLocation(), diag::ext_anonymous_union); 1609 else if (!Record->isUnion()) 1610 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1611 1612 // C and C++ require different kinds of checks for anonymous 1613 // structs/unions. 1614 bool Invalid = false; 1615 if (getLangOptions().CPlusPlus) { 1616 const char* PrevSpec = 0; 1617 unsigned DiagID; 1618 // C++ [class.union]p3: 1619 // Anonymous unions declared in a named namespace or in the 1620 // global namespace shall be declared static. 1621 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1622 (isa<TranslationUnitDecl>(Owner) || 1623 (isa<NamespaceDecl>(Owner) && 1624 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1625 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1626 Invalid = true; 1627 1628 // Recover by adding 'static'. 1629 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1630 PrevSpec, DiagID); 1631 } 1632 // C++ [class.union]p3: 1633 // A storage class is not allowed in a declaration of an 1634 // anonymous union in a class scope. 1635 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1636 isa<RecordDecl>(Owner)) { 1637 Diag(DS.getStorageClassSpecLoc(), 1638 diag::err_anonymous_union_with_storage_spec); 1639 Invalid = true; 1640 1641 // Recover by removing the storage specifier. 1642 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1643 PrevSpec, DiagID); 1644 } 1645 1646 // C++ [class.union]p2: 1647 // The member-specification of an anonymous union shall only 1648 // define non-static data members. [Note: nested types and 1649 // functions cannot be declared within an anonymous union. ] 1650 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1651 MemEnd = Record->decls_end(); 1652 Mem != MemEnd; ++Mem) { 1653 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1654 // C++ [class.union]p3: 1655 // An anonymous union shall not have private or protected 1656 // members (clause 11). 1657 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1658 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1659 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1660 Invalid = true; 1661 } 1662 } else if ((*Mem)->isImplicit()) { 1663 // Any implicit members are fine. 1664 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1665 // This is a type that showed up in an 1666 // elaborated-type-specifier inside the anonymous struct or 1667 // union, but which actually declares a type outside of the 1668 // anonymous struct or union. It's okay. 1669 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1670 if (!MemRecord->isAnonymousStructOrUnion() && 1671 MemRecord->getDeclName()) { 1672 // This is a nested type declaration. 1673 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1674 << (int)Record->isUnion(); 1675 Invalid = true; 1676 } 1677 } else { 1678 // We have something that isn't a non-static data 1679 // member. Complain about it. 1680 unsigned DK = diag::err_anonymous_record_bad_member; 1681 if (isa<TypeDecl>(*Mem)) 1682 DK = diag::err_anonymous_record_with_type; 1683 else if (isa<FunctionDecl>(*Mem)) 1684 DK = diag::err_anonymous_record_with_function; 1685 else if (isa<VarDecl>(*Mem)) 1686 DK = diag::err_anonymous_record_with_static; 1687 Diag((*Mem)->getLocation(), DK) 1688 << (int)Record->isUnion(); 1689 Invalid = true; 1690 } 1691 } 1692 } 1693 1694 if (!Record->isUnion() && !Owner->isRecord()) { 1695 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1696 << (int)getLangOptions().CPlusPlus; 1697 Invalid = true; 1698 } 1699 1700 // Mock up a declarator. 1701 Declarator Dc(DS, Declarator::TypeNameContext); 1702 TypeSourceInfo *TInfo = 0; 1703 GetTypeForDeclarator(Dc, S, &TInfo); 1704 assert(TInfo && "couldn't build declarator info for anonymous struct/union"); 1705 1706 // Create a declaration for this anonymous struct/union. 1707 NamedDecl *Anon = 0; 1708 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1709 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1710 /*IdentifierInfo=*/0, 1711 Context.getTypeDeclType(Record), 1712 TInfo, 1713 /*BitWidth=*/0, /*Mutable=*/false); 1714 Anon->setAccess(AS_public); 1715 if (getLangOptions().CPlusPlus) 1716 FieldCollector->Add(cast<FieldDecl>(Anon)); 1717 } else { 1718 VarDecl::StorageClass SC; 1719 switch (DS.getStorageClassSpec()) { 1720 default: assert(0 && "Unknown storage class!"); 1721 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1722 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1723 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1724 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1725 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1726 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1727 case DeclSpec::SCS_mutable: 1728 // mutable can only appear on non-static class members, so it's always 1729 // an error here 1730 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1731 Invalid = true; 1732 SC = VarDecl::None; 1733 break; 1734 } 1735 1736 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1737 /*IdentifierInfo=*/0, 1738 Context.getTypeDeclType(Record), 1739 TInfo, 1740 SC); 1741 } 1742 Anon->setImplicit(); 1743 1744 // Add the anonymous struct/union object to the current 1745 // context. We'll be referencing this object when we refer to one of 1746 // its members. 1747 Owner->addDecl(Anon); 1748 1749 // Inject the members of the anonymous struct/union into the owning 1750 // context and into the identifier resolver chain for name lookup 1751 // purposes. 1752 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1753 Invalid = true; 1754 1755 // Mark this as an anonymous struct/union type. Note that we do not 1756 // do this until after we have already checked and injected the 1757 // members of this anonymous struct/union type, because otherwise 1758 // the members could be injected twice: once by DeclContext when it 1759 // builds its lookup table, and once by 1760 // InjectAnonymousStructOrUnionMembers. 1761 Record->setAnonymousStructOrUnion(true); 1762 1763 if (Invalid) 1764 Anon->setInvalidDecl(); 1765 1766 return DeclPtrTy::make(Anon); 1767} 1768 1769 1770/// GetNameForDeclarator - Determine the full declaration name for the 1771/// given Declarator. 1772DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1773 return GetNameFromUnqualifiedId(D.getName()); 1774} 1775 1776/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1777DeclarationName Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) { 1778 switch (Name.getKind()) { 1779 case UnqualifiedId::IK_Identifier: 1780 return DeclarationName(Name.Identifier); 1781 1782 case UnqualifiedId::IK_OperatorFunctionId: 1783 return Context.DeclarationNames.getCXXOperatorName( 1784 Name.OperatorFunctionId.Operator); 1785 1786 case UnqualifiedId::IK_LiteralOperatorId: 1787 return Context.DeclarationNames.getCXXLiteralOperatorName( 1788 Name.Identifier); 1789 1790 case UnqualifiedId::IK_ConversionFunctionId: { 1791 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1792 if (Ty.isNull()) 1793 return DeclarationName(); 1794 1795 return Context.DeclarationNames.getCXXConversionFunctionName( 1796 Context.getCanonicalType(Ty)); 1797 } 1798 1799 case UnqualifiedId::IK_ConstructorName: { 1800 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1801 if (Ty.isNull()) 1802 return DeclarationName(); 1803 1804 return Context.DeclarationNames.getCXXConstructorName( 1805 Context.getCanonicalType(Ty)); 1806 } 1807 1808 case UnqualifiedId::IK_DestructorName: { 1809 QualType Ty = GetTypeFromParser(Name.DestructorName); 1810 if (Ty.isNull()) 1811 return DeclarationName(); 1812 1813 return Context.DeclarationNames.getCXXDestructorName( 1814 Context.getCanonicalType(Ty)); 1815 } 1816 1817 case UnqualifiedId::IK_TemplateId: { 1818 TemplateName TName 1819 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1820 return Context.getNameForTemplate(TName); 1821 } 1822 } 1823 1824 assert(false && "Unknown name kind"); 1825 return DeclarationName(); 1826} 1827 1828/// isNearlyMatchingFunction - Determine whether the C++ functions 1829/// Declaration and Definition are "nearly" matching. This heuristic 1830/// is used to improve diagnostics in the case where an out-of-line 1831/// function definition doesn't match any declaration within 1832/// the class or namespace. 1833static bool isNearlyMatchingFunction(ASTContext &Context, 1834 FunctionDecl *Declaration, 1835 FunctionDecl *Definition) { 1836 if (Declaration->param_size() != Definition->param_size()) 1837 return false; 1838 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1839 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1840 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1841 1842 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1843 DefParamTy.getNonReferenceType())) 1844 return false; 1845 } 1846 1847 return true; 1848} 1849 1850Sema::DeclPtrTy 1851Sema::HandleDeclarator(Scope *S, Declarator &D, 1852 MultiTemplateParamsArg TemplateParamLists, 1853 bool IsFunctionDefinition) { 1854 DeclarationName Name = GetNameForDeclarator(D); 1855 1856 // All of these full declarators require an identifier. If it doesn't have 1857 // one, the ParsedFreeStandingDeclSpec action should be used. 1858 if (!Name) { 1859 if (!D.isInvalidType()) // Reject this if we think it is valid. 1860 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1861 diag::err_declarator_need_ident) 1862 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1863 return DeclPtrTy(); 1864 } 1865 1866 // The scope passed in may not be a decl scope. Zip up the scope tree until 1867 // we find one that is. 1868 while ((S->getFlags() & Scope::DeclScope) == 0 || 1869 (S->getFlags() & Scope::TemplateParamScope) != 0) 1870 S = S->getParent(); 1871 1872 // If this is an out-of-line definition of a member of a class template 1873 // or class template partial specialization, we may need to rebuild the 1874 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1875 // for more information. 1876 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1877 // handle expressions properly. 1878 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1879 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1880 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1881 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1882 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1883 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1884 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1885 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1886 // FIXME: Preserve type source info. 1887 QualType T = GetTypeFromParser(DS.getTypeRep()); 1888 EnterDeclaratorContext(S, DC); 1889 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1890 ExitDeclaratorContext(S); 1891 if (T.isNull()) 1892 return DeclPtrTy(); 1893 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1894 } 1895 } 1896 1897 DeclContext *DC; 1898 NamedDecl *New; 1899 1900 TypeSourceInfo *TInfo = 0; 1901 QualType R = GetTypeForDeclarator(D, S, &TInfo); 1902 1903 LookupResult Previous(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1904 ForRedeclaration); 1905 1906 // See if this is a redefinition of a variable in the same scope. 1907 if (D.getCXXScopeSpec().isInvalid()) { 1908 DC = CurContext; 1909 D.setInvalidType(); 1910 } else if (!D.getCXXScopeSpec().isSet()) { 1911 bool IsLinkageLookup = false; 1912 1913 // If the declaration we're planning to build will be a function 1914 // or object with linkage, then look for another declaration with 1915 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1916 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1917 /* Do nothing*/; 1918 else if (R->isFunctionType()) { 1919 if (CurContext->isFunctionOrMethod() || 1920 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1921 IsLinkageLookup = true; 1922 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1923 IsLinkageLookup = true; 1924 else if (CurContext->getLookupContext()->isTranslationUnit() && 1925 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1926 IsLinkageLookup = true; 1927 1928 if (IsLinkageLookup) 1929 Previous.clear(LookupRedeclarationWithLinkage); 1930 1931 DC = CurContext; 1932 LookupName(Previous, S, /* CreateBuiltins = */ IsLinkageLookup); 1933 } else { // Something like "int foo::x;" 1934 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1935 1936 if (!DC) { 1937 // If we could not compute the declaration context, it's because the 1938 // declaration context is dependent but does not refer to a class, 1939 // class template, or class template partial specialization. Complain 1940 // and return early, to avoid the coming semantic disaster. 1941 Diag(D.getIdentifierLoc(), 1942 diag::err_template_qualified_declarator_no_match) 1943 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1944 << D.getCXXScopeSpec().getRange(); 1945 return DeclPtrTy(); 1946 } 1947 1948 if (!DC->isDependentContext() && 1949 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1950 return DeclPtrTy(); 1951 1952 LookupQualifiedName(Previous, DC); 1953 1954 // Don't consider using declarations as previous declarations for 1955 // out-of-line members. 1956 RemoveUsingDecls(Previous); 1957 1958 // C++ 7.3.1.2p2: 1959 // Members (including explicit specializations of templates) of a named 1960 // namespace can also be defined outside that namespace by explicit 1961 // qualification of the name being defined, provided that the entity being 1962 // defined was already declared in the namespace and the definition appears 1963 // after the point of declaration in a namespace that encloses the 1964 // declarations namespace. 1965 // 1966 // Note that we only check the context at this point. We don't yet 1967 // have enough information to make sure that PrevDecl is actually 1968 // the declaration we want to match. For example, given: 1969 // 1970 // class X { 1971 // void f(); 1972 // void f(float); 1973 // }; 1974 // 1975 // void X::f(int) { } // ill-formed 1976 // 1977 // In this case, PrevDecl will point to the overload set 1978 // containing the two f's declared in X, but neither of them 1979 // matches. 1980 1981 // First check whether we named the global scope. 1982 if (isa<TranslationUnitDecl>(DC)) { 1983 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1984 << Name << D.getCXXScopeSpec().getRange(); 1985 } else { 1986 DeclContext *Cur = CurContext; 1987 while (isa<LinkageSpecDecl>(Cur)) 1988 Cur = Cur->getParent(); 1989 if (!Cur->Encloses(DC)) { 1990 // The qualifying scope doesn't enclose the original declaration. 1991 // Emit diagnostic based on current scope. 1992 SourceLocation L = D.getIdentifierLoc(); 1993 SourceRange R = D.getCXXScopeSpec().getRange(); 1994 if (isa<FunctionDecl>(Cur)) 1995 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1996 else 1997 Diag(L, diag::err_invalid_declarator_scope) 1998 << Name << cast<NamedDecl>(DC) << R; 1999 D.setInvalidType(); 2000 } 2001 } 2002 } 2003 2004 if (Previous.isSingleResult() && 2005 Previous.getFoundDecl()->isTemplateParameter()) { 2006 // Maybe we will complain about the shadowed template parameter. 2007 if (!D.isInvalidType()) 2008 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), 2009 Previous.getFoundDecl())) 2010 D.setInvalidType(); 2011 2012 // Just pretend that we didn't see the previous declaration. 2013 Previous.clear(); 2014 } 2015 2016 // In C++, the previous declaration we find might be a tag type 2017 // (class or enum). In this case, the new declaration will hide the 2018 // tag type. Note that this does does not apply if we're declaring a 2019 // typedef (C++ [dcl.typedef]p4). 2020 if (Previous.isSingleTagDecl() && 2021 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 2022 Previous.clear(); 2023 2024 bool Redeclaration = false; 2025 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 2026 if (TemplateParamLists.size()) { 2027 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 2028 return DeclPtrTy(); 2029 } 2030 2031 New = ActOnTypedefDeclarator(S, D, DC, R, TInfo, Previous, Redeclaration); 2032 } else if (R->isFunctionType()) { 2033 New = ActOnFunctionDeclarator(S, D, DC, R, TInfo, Previous, 2034 move(TemplateParamLists), 2035 IsFunctionDefinition, Redeclaration); 2036 } else { 2037 New = ActOnVariableDeclarator(S, D, DC, R, TInfo, Previous, 2038 move(TemplateParamLists), 2039 Redeclaration); 2040 } 2041 2042 if (New == 0) 2043 return DeclPtrTy(); 2044 2045 // If this has an identifier and is not an invalid redeclaration or 2046 // function template specialization, add it to the scope stack. 2047 if (Name && !(Redeclaration && New->isInvalidDecl())) 2048 PushOnScopeChains(New, S); 2049 2050 return DeclPtrTy::make(New); 2051} 2052 2053/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 2054/// types into constant array types in certain situations which would otherwise 2055/// be errors (for GCC compatibility). 2056static QualType TryToFixInvalidVariablyModifiedType(QualType T, 2057 ASTContext &Context, 2058 bool &SizeIsNegative) { 2059 // This method tries to turn a variable array into a constant 2060 // array even when the size isn't an ICE. This is necessary 2061 // for compatibility with code that depends on gcc's buggy 2062 // constant expression folding, like struct {char x[(int)(char*)2];} 2063 SizeIsNegative = false; 2064 2065 QualifierCollector Qs; 2066 const Type *Ty = Qs.strip(T); 2067 2068 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 2069 QualType Pointee = PTy->getPointeeType(); 2070 QualType FixedType = 2071 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 2072 if (FixedType.isNull()) return FixedType; 2073 FixedType = Context.getPointerType(FixedType); 2074 return Qs.apply(FixedType); 2075 } 2076 2077 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 2078 if (!VLATy) 2079 return QualType(); 2080 // FIXME: We should probably handle this case 2081 if (VLATy->getElementType()->isVariablyModifiedType()) 2082 return QualType(); 2083 2084 Expr::EvalResult EvalResult; 2085 if (!VLATy->getSizeExpr() || 2086 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 2087 !EvalResult.Val.isInt()) 2088 return QualType(); 2089 2090 llvm::APSInt &Res = EvalResult.Val.getInt(); 2091 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 2092 // TODO: preserve the size expression in declarator info 2093 return Context.getConstantArrayType(VLATy->getElementType(), 2094 Res, ArrayType::Normal, 0); 2095 } 2096 2097 SizeIsNegative = true; 2098 return QualType(); 2099} 2100 2101/// \brief Register the given locally-scoped external C declaration so 2102/// that it can be found later for redeclarations 2103void 2104Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, 2105 const LookupResult &Previous, 2106 Scope *S) { 2107 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 2108 "Decl is not a locally-scoped decl!"); 2109 // Note that we have a locally-scoped external with this name. 2110 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 2111 2112 if (!Previous.isSingleResult()) 2113 return; 2114 2115 NamedDecl *PrevDecl = Previous.getFoundDecl(); 2116 2117 // If there was a previous declaration of this variable, it may be 2118 // in our identifier chain. Update the identifier chain with the new 2119 // declaration. 2120 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 2121 // The previous declaration was found on the identifer resolver 2122 // chain, so remove it from its scope. 2123 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 2124 S = S->getParent(); 2125 2126 if (S) 2127 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 2128 } 2129} 2130 2131/// \brief Diagnose function specifiers on a declaration of an identifier that 2132/// does not identify a function. 2133void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2134 // FIXME: We should probably indicate the identifier in question to avoid 2135 // confusion for constructs like "inline int a(), b;" 2136 if (D.getDeclSpec().isInlineSpecified()) 2137 Diag(D.getDeclSpec().getInlineSpecLoc(), 2138 diag::err_inline_non_function); 2139 2140 if (D.getDeclSpec().isVirtualSpecified()) 2141 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2142 diag::err_virtual_non_function); 2143 2144 if (D.getDeclSpec().isExplicitSpecified()) 2145 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2146 diag::err_explicit_non_function); 2147} 2148 2149NamedDecl* 2150Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2151 QualType R, TypeSourceInfo *TInfo, 2152 LookupResult &Previous, bool &Redeclaration) { 2153 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2154 if (D.getCXXScopeSpec().isSet()) { 2155 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2156 << D.getCXXScopeSpec().getRange(); 2157 D.setInvalidType(); 2158 // Pretend we didn't see the scope specifier. 2159 DC = 0; 2160 } 2161 2162 if (getLangOptions().CPlusPlus) { 2163 // Check that there are no default arguments (C++ only). 2164 CheckExtraCXXDefaultArguments(D); 2165 } 2166 2167 DiagnoseFunctionSpecifiers(D); 2168 2169 if (D.getDeclSpec().isThreadSpecified()) 2170 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2171 2172 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, TInfo); 2173 if (!NewTD) return 0; 2174 2175 // Handle attributes prior to checking for duplicates in MergeVarDecl 2176 ProcessDeclAttributes(S, NewTD, D); 2177 2178 // Merge the decl with the existing one if appropriate. If the decl is 2179 // in an outer scope, it isn't the same thing. 2180 FilterLookupForScope(*this, Previous, DC, S, /*ConsiderLinkage*/ false); 2181 if (!Previous.empty()) { 2182 Redeclaration = true; 2183 MergeTypeDefDecl(NewTD, Previous); 2184 } 2185 2186 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2187 // then it shall have block scope. 2188 QualType T = NewTD->getUnderlyingType(); 2189 if (T->isVariablyModifiedType()) { 2190 CurFunctionNeedsScopeChecking = true; 2191 2192 if (S->getFnParent() == 0) { 2193 bool SizeIsNegative; 2194 QualType FixedTy = 2195 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2196 if (!FixedTy.isNull()) { 2197 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2198 NewTD->setTypeSourceInfo(Context.getTrivialTypeSourceInfo(FixedTy)); 2199 } else { 2200 if (SizeIsNegative) 2201 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2202 else if (T->isVariableArrayType()) 2203 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2204 else 2205 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2206 NewTD->setInvalidDecl(); 2207 } 2208 } 2209 } 2210 2211 // If this is the C FILE type, notify the AST context. 2212 if (IdentifierInfo *II = NewTD->getIdentifier()) 2213 if (!NewTD->isInvalidDecl() && 2214 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2215 if (II->isStr("FILE")) 2216 Context.setFILEDecl(NewTD); 2217 else if (II->isStr("jmp_buf")) 2218 Context.setjmp_bufDecl(NewTD); 2219 else if (II->isStr("sigjmp_buf")) 2220 Context.setsigjmp_bufDecl(NewTD); 2221 } 2222 2223 return NewTD; 2224} 2225 2226/// \brief Determines whether the given declaration is an out-of-scope 2227/// previous declaration. 2228/// 2229/// This routine should be invoked when name lookup has found a 2230/// previous declaration (PrevDecl) that is not in the scope where a 2231/// new declaration by the same name is being introduced. If the new 2232/// declaration occurs in a local scope, previous declarations with 2233/// linkage may still be considered previous declarations (C99 2234/// 6.2.2p4-5, C++ [basic.link]p6). 2235/// 2236/// \param PrevDecl the previous declaration found by name 2237/// lookup 2238/// 2239/// \param DC the context in which the new declaration is being 2240/// declared. 2241/// 2242/// \returns true if PrevDecl is an out-of-scope previous declaration 2243/// for a new delcaration with the same name. 2244static bool 2245isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2246 ASTContext &Context) { 2247 if (!PrevDecl) 2248 return 0; 2249 2250 if (!PrevDecl->hasLinkage()) 2251 return false; 2252 2253 if (Context.getLangOptions().CPlusPlus) { 2254 // C++ [basic.link]p6: 2255 // If there is a visible declaration of an entity with linkage 2256 // having the same name and type, ignoring entities declared 2257 // outside the innermost enclosing namespace scope, the block 2258 // scope declaration declares that same entity and receives the 2259 // linkage of the previous declaration. 2260 DeclContext *OuterContext = DC->getLookupContext(); 2261 if (!OuterContext->isFunctionOrMethod()) 2262 // This rule only applies to block-scope declarations. 2263 return false; 2264 else { 2265 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2266 if (PrevOuterContext->isRecord()) 2267 // We found a member function: ignore it. 2268 return false; 2269 else { 2270 // Find the innermost enclosing namespace for the new and 2271 // previous declarations. 2272 while (!OuterContext->isFileContext()) 2273 OuterContext = OuterContext->getParent(); 2274 while (!PrevOuterContext->isFileContext()) 2275 PrevOuterContext = PrevOuterContext->getParent(); 2276 2277 // The previous declaration is in a different namespace, so it 2278 // isn't the same function. 2279 if (OuterContext->getPrimaryContext() != 2280 PrevOuterContext->getPrimaryContext()) 2281 return false; 2282 } 2283 } 2284 } 2285 2286 return true; 2287} 2288 2289NamedDecl* 2290Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2291 QualType R, TypeSourceInfo *TInfo, 2292 LookupResult &Previous, 2293 MultiTemplateParamsArg TemplateParamLists, 2294 bool &Redeclaration) { 2295 DeclarationName Name = GetNameForDeclarator(D); 2296 2297 // Check that there are no default arguments (C++ only). 2298 if (getLangOptions().CPlusPlus) 2299 CheckExtraCXXDefaultArguments(D); 2300 2301 VarDecl *NewVD; 2302 VarDecl::StorageClass SC; 2303 switch (D.getDeclSpec().getStorageClassSpec()) { 2304 default: assert(0 && "Unknown storage class!"); 2305 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2306 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2307 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2308 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2309 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2310 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2311 case DeclSpec::SCS_mutable: 2312 // mutable can only appear on non-static class members, so it's always 2313 // an error here 2314 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2315 D.setInvalidType(); 2316 SC = VarDecl::None; 2317 break; 2318 } 2319 2320 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2321 if (!II) { 2322 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2323 << Name.getAsString(); 2324 return 0; 2325 } 2326 2327 DiagnoseFunctionSpecifiers(D); 2328 2329 if (!DC->isRecord() && S->getFnParent() == 0) { 2330 // C99 6.9p2: The storage-class specifiers auto and register shall not 2331 // appear in the declaration specifiers in an external declaration. 2332 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2333 2334 // If this is a register variable with an asm label specified, then this 2335 // is a GNU extension. 2336 if (SC == VarDecl::Register && D.getAsmLabel()) 2337 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2338 else 2339 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2340 D.setInvalidType(); 2341 } 2342 } 2343 if (DC->isRecord() && !CurContext->isRecord()) { 2344 // This is an out-of-line definition of a static data member. 2345 if (SC == VarDecl::Static) { 2346 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2347 diag::err_static_out_of_line) 2348 << CodeModificationHint::CreateRemoval( 2349 D.getDeclSpec().getStorageClassSpecLoc()); 2350 } else if (SC == VarDecl::None) 2351 SC = VarDecl::Static; 2352 } 2353 if (SC == VarDecl::Static) { 2354 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2355 if (RD->isLocalClass()) 2356 Diag(D.getIdentifierLoc(), 2357 diag::err_static_data_member_not_allowed_in_local_class) 2358 << Name << RD->getDeclName(); 2359 } 2360 } 2361 2362 // Match up the template parameter lists with the scope specifier, then 2363 // determine whether we have a template or a template specialization. 2364 bool isExplicitSpecialization = false; 2365 if (TemplateParameterList *TemplateParams 2366 = MatchTemplateParametersToScopeSpecifier( 2367 D.getDeclSpec().getSourceRange().getBegin(), 2368 D.getCXXScopeSpec(), 2369 (TemplateParameterList**)TemplateParamLists.get(), 2370 TemplateParamLists.size(), 2371 isExplicitSpecialization)) { 2372 if (TemplateParams->size() > 0) { 2373 // There is no such thing as a variable template. 2374 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2375 << II 2376 << SourceRange(TemplateParams->getTemplateLoc(), 2377 TemplateParams->getRAngleLoc()); 2378 return 0; 2379 } else { 2380 // There is an extraneous 'template<>' for this variable. Complain 2381 // about it, but allow the declaration of the variable. 2382 Diag(TemplateParams->getTemplateLoc(), 2383 diag::err_template_variable_noparams) 2384 << II 2385 << SourceRange(TemplateParams->getTemplateLoc(), 2386 TemplateParams->getRAngleLoc()); 2387 2388 isExplicitSpecialization = true; 2389 } 2390 } 2391 2392 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2393 II, R, TInfo, SC); 2394 2395 if (D.isInvalidType()) 2396 NewVD->setInvalidDecl(); 2397 2398 if (D.getDeclSpec().isThreadSpecified()) { 2399 if (NewVD->hasLocalStorage()) 2400 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2401 else if (!Context.Target.isTLSSupported()) 2402 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2403 else 2404 NewVD->setThreadSpecified(true); 2405 } 2406 2407 // Set the lexical context. If the declarator has a C++ scope specifier, the 2408 // lexical context will be different from the semantic context. 2409 NewVD->setLexicalDeclContext(CurContext); 2410 2411 // Handle attributes prior to checking for duplicates in MergeVarDecl 2412 ProcessDeclAttributes(S, NewVD, D); 2413 2414 // Handle GNU asm-label extension (encoded as an attribute). 2415 if (Expr *E = (Expr*) D.getAsmLabel()) { 2416 // The parser guarantees this is a string. 2417 StringLiteral *SE = cast<StringLiteral>(E); 2418 NewVD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2419 } 2420 2421 // Don't consider existing declarations that are in a different 2422 // scope and are out-of-semantic-context declarations (if the new 2423 // declaration has linkage). 2424 FilterLookupForScope(*this, Previous, DC, S, NewVD->hasLinkage()); 2425 2426 // Merge the decl with the existing one if appropriate. 2427 if (!Previous.empty()) { 2428 if (Previous.isSingleResult() && 2429 isa<FieldDecl>(Previous.getFoundDecl()) && 2430 D.getCXXScopeSpec().isSet()) { 2431 // The user tried to define a non-static data member 2432 // out-of-line (C++ [dcl.meaning]p1). 2433 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2434 << D.getCXXScopeSpec().getRange(); 2435 Previous.clear(); 2436 NewVD->setInvalidDecl(); 2437 } 2438 } else if (D.getCXXScopeSpec().isSet()) { 2439 // No previous declaration in the qualifying scope. 2440 Diag(D.getIdentifierLoc(), diag::err_no_member) 2441 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2442 << D.getCXXScopeSpec().getRange(); 2443 NewVD->setInvalidDecl(); 2444 } 2445 2446 CheckVariableDeclaration(NewVD, Previous, Redeclaration); 2447 2448 // This is an explicit specialization of a static data member. Check it. 2449 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2450 CheckMemberSpecialization(NewVD, Previous)) 2451 NewVD->setInvalidDecl(); 2452 2453 // attributes declared post-definition are currently ignored 2454 if (Previous.isSingleResult()) { 2455 const VarDecl *Def = 0; 2456 VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl()); 2457 if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) { 2458 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2459 Diag(Def->getLocation(), diag::note_previous_definition); 2460 } 2461 } 2462 2463 // If this is a locally-scoped extern C variable, update the map of 2464 // such variables. 2465 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2466 !NewVD->isInvalidDecl()) 2467 RegisterLocallyScopedExternCDecl(NewVD, Previous, S); 2468 2469 return NewVD; 2470} 2471 2472/// \brief Perform semantic checking on a newly-created variable 2473/// declaration. 2474/// 2475/// This routine performs all of the type-checking required for a 2476/// variable declaration once it has been built. It is used both to 2477/// check variables after they have been parsed and their declarators 2478/// have been translated into a declaration, and to check variables 2479/// that have been instantiated from a template. 2480/// 2481/// Sets NewVD->isInvalidDecl() if an error was encountered. 2482void Sema::CheckVariableDeclaration(VarDecl *NewVD, 2483 LookupResult &Previous, 2484 bool &Redeclaration) { 2485 // If the decl is already known invalid, don't check it. 2486 if (NewVD->isInvalidDecl()) 2487 return; 2488 2489 QualType T = NewVD->getType(); 2490 2491 if (T->isObjCInterfaceType()) { 2492 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2493 return NewVD->setInvalidDecl(); 2494 } 2495 2496 // Emit an error if an address space was applied to decl with local storage. 2497 // This includes arrays of objects with address space qualifiers, but not 2498 // automatic variables that point to other address spaces. 2499 // ISO/IEC TR 18037 S5.1.2 2500 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2501 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2502 return NewVD->setInvalidDecl(); 2503 } 2504 2505 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2506 && !NewVD->hasAttr<BlocksAttr>()) 2507 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2508 2509 bool isVM = T->isVariablyModifiedType(); 2510 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2511 NewVD->hasAttr<BlocksAttr>()) 2512 CurFunctionNeedsScopeChecking = true; 2513 2514 if ((isVM && NewVD->hasLinkage()) || 2515 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2516 bool SizeIsNegative; 2517 QualType FixedTy = 2518 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2519 2520 if (FixedTy.isNull() && T->isVariableArrayType()) { 2521 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2522 // FIXME: This won't give the correct result for 2523 // int a[10][n]; 2524 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2525 2526 if (NewVD->isFileVarDecl()) 2527 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2528 << SizeRange; 2529 else if (NewVD->getStorageClass() == VarDecl::Static) 2530 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2531 << SizeRange; 2532 else 2533 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2534 << SizeRange; 2535 return NewVD->setInvalidDecl(); 2536 } 2537 2538 if (FixedTy.isNull()) { 2539 if (NewVD->isFileVarDecl()) 2540 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2541 else 2542 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2543 return NewVD->setInvalidDecl(); 2544 } 2545 2546 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2547 NewVD->setType(FixedTy); 2548 } 2549 2550 if (Previous.empty() && NewVD->isExternC()) { 2551 // Since we did not find anything by this name and we're declaring 2552 // an extern "C" variable, look for a non-visible extern "C" 2553 // declaration with the same name. 2554 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2555 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2556 if (Pos != LocallyScopedExternalDecls.end()) 2557 Previous.addDecl(Pos->second); 2558 } 2559 2560 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2561 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2562 << T; 2563 return NewVD->setInvalidDecl(); 2564 } 2565 2566 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2567 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2568 return NewVD->setInvalidDecl(); 2569 } 2570 2571 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2572 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2573 return NewVD->setInvalidDecl(); 2574 } 2575 2576 if (!Previous.empty()) { 2577 Redeclaration = true; 2578 MergeVarDecl(NewVD, Previous); 2579 } 2580} 2581 2582/// \brief Data used with FindOverriddenMethod 2583struct FindOverriddenMethodData { 2584 Sema *S; 2585 CXXMethodDecl *Method; 2586}; 2587 2588/// \brief Member lookup function that determines whether a given C++ 2589/// method overrides a method in a base class, to be used with 2590/// CXXRecordDecl::lookupInBases(). 2591static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2592 CXXBasePath &Path, 2593 void *UserData) { 2594 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2595 2596 FindOverriddenMethodData *Data 2597 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2598 2599 DeclarationName Name = Data->Method->getDeclName(); 2600 2601 // FIXME: Do we care about other names here too? 2602 if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2603 // We really want to find the base class constructor here. 2604 QualType T = Data->S->Context.getTypeDeclType(BaseRecord); 2605 CanQualType CT = Data->S->Context.getCanonicalType(T); 2606 2607 Name = Data->S->Context.DeclarationNames.getCXXDestructorName(CT); 2608 } 2609 2610 for (Path.Decls = BaseRecord->lookup(Name); 2611 Path.Decls.first != Path.Decls.second; 2612 ++Path.Decls.first) { 2613 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2614 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD)) 2615 return true; 2616 } 2617 } 2618 2619 return false; 2620} 2621 2622/// AddOverriddenMethods - See if a method overrides any in the base classes, 2623/// and if so, check that it's a valid override and remember it. 2624void Sema::AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD) { 2625 // Look for virtual methods in base classes that this method might override. 2626 CXXBasePaths Paths; 2627 FindOverriddenMethodData Data; 2628 Data.Method = MD; 2629 Data.S = this; 2630 if (DC->lookupInBases(&FindOverriddenMethod, &Data, Paths)) { 2631 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2632 E = Paths.found_decls_end(); I != E; ++I) { 2633 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2634 if (!CheckOverridingFunctionReturnType(MD, OldMD) && 2635 !CheckOverridingFunctionExceptionSpec(MD, OldMD) && 2636 !CheckOverridingFunctionAttributes(MD, OldMD)) 2637 MD->addOverriddenMethod(OldMD->getCanonicalDecl()); 2638 } 2639 } 2640 } 2641} 2642 2643NamedDecl* 2644Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2645 QualType R, TypeSourceInfo *TInfo, 2646 LookupResult &Previous, 2647 MultiTemplateParamsArg TemplateParamLists, 2648 bool IsFunctionDefinition, bool &Redeclaration) { 2649 assert(R.getTypePtr()->isFunctionType()); 2650 2651 DeclarationName Name = GetNameForDeclarator(D); 2652 FunctionDecl::StorageClass SC = FunctionDecl::None; 2653 switch (D.getDeclSpec().getStorageClassSpec()) { 2654 default: assert(0 && "Unknown storage class!"); 2655 case DeclSpec::SCS_auto: 2656 case DeclSpec::SCS_register: 2657 case DeclSpec::SCS_mutable: 2658 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2659 diag::err_typecheck_sclass_func); 2660 D.setInvalidType(); 2661 break; 2662 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2663 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2664 case DeclSpec::SCS_static: { 2665 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2666 // C99 6.7.1p5: 2667 // The declaration of an identifier for a function that has 2668 // block scope shall have no explicit storage-class specifier 2669 // other than extern 2670 // See also (C++ [dcl.stc]p4). 2671 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2672 diag::err_static_block_func); 2673 SC = FunctionDecl::None; 2674 } else 2675 SC = FunctionDecl::Static; 2676 break; 2677 } 2678 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2679 } 2680 2681 if (D.getDeclSpec().isThreadSpecified()) 2682 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2683 2684 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2685 bool isInline = D.getDeclSpec().isInlineSpecified(); 2686 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2687 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2688 2689 // Check that the return type is not an abstract class type. 2690 // For record types, this is done by the AbstractClassUsageDiagnoser once 2691 // the class has been completely parsed. 2692 if (!DC->isRecord() && 2693 RequireNonAbstractType(D.getIdentifierLoc(), 2694 R->getAs<FunctionType>()->getResultType(), 2695 diag::err_abstract_type_in_decl, 2696 AbstractReturnType)) 2697 D.setInvalidType(); 2698 2699 // Do not allow returning a objc interface by-value. 2700 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2701 Diag(D.getIdentifierLoc(), 2702 diag::err_object_cannot_be_passed_returned_by_value) << 0 2703 << R->getAs<FunctionType>()->getResultType(); 2704 D.setInvalidType(); 2705 } 2706 2707 bool isVirtualOkay = false; 2708 FunctionDecl *NewFD; 2709 2710 if (isFriend) { 2711 // C++ [class.friend]p5 2712 // A function can be defined in a friend declaration of a 2713 // class . . . . Such a function is implicitly inline. 2714 isInline |= IsFunctionDefinition; 2715 } 2716 2717 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2718 // This is a C++ constructor declaration. 2719 assert(DC->isRecord() && 2720 "Constructors can only be declared in a member context"); 2721 2722 R = CheckConstructorDeclarator(D, R, SC); 2723 2724 // Create the new declaration 2725 NewFD = CXXConstructorDecl::Create(Context, 2726 cast<CXXRecordDecl>(DC), 2727 D.getIdentifierLoc(), Name, R, TInfo, 2728 isExplicit, isInline, 2729 /*isImplicitlyDeclared=*/false); 2730 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2731 // This is a C++ destructor declaration. 2732 if (DC->isRecord()) { 2733 R = CheckDestructorDeclarator(D, SC); 2734 2735 NewFD = CXXDestructorDecl::Create(Context, 2736 cast<CXXRecordDecl>(DC), 2737 D.getIdentifierLoc(), Name, R, 2738 isInline, 2739 /*isImplicitlyDeclared=*/false); 2740 2741 isVirtualOkay = true; 2742 } else { 2743 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2744 2745 // Create a FunctionDecl to satisfy the function definition parsing 2746 // code path. 2747 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2748 Name, R, TInfo, SC, isInline, 2749 /*hasPrototype=*/true); 2750 D.setInvalidType(); 2751 } 2752 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2753 if (!DC->isRecord()) { 2754 Diag(D.getIdentifierLoc(), 2755 diag::err_conv_function_not_member); 2756 return 0; 2757 } 2758 2759 CheckConversionDeclarator(D, R, SC); 2760 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2761 D.getIdentifierLoc(), Name, R, TInfo, 2762 isInline, isExplicit); 2763 2764 isVirtualOkay = true; 2765 } else if (DC->isRecord()) { 2766 // If the of the function is the same as the name of the record, then this 2767 // must be an invalid constructor that has a return type. 2768 // (The parser checks for a return type and makes the declarator a 2769 // constructor if it has no return type). 2770 // must have an invalid constructor that has a return type 2771 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2772 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2773 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2774 << SourceRange(D.getIdentifierLoc()); 2775 return 0; 2776 } 2777 2778 bool isStatic = SC == FunctionDecl::Static; 2779 2780 // [class.free]p1: 2781 // Any allocation function for a class T is a static member 2782 // (even if not explicitly declared static). 2783 if (Name.getCXXOverloadedOperator() == OO_New || 2784 Name.getCXXOverloadedOperator() == OO_Array_New) 2785 isStatic = true; 2786 2787 // [class.free]p6 Any deallocation function for a class X is a static member 2788 // (even if not explicitly declared static). 2789 if (Name.getCXXOverloadedOperator() == OO_Delete || 2790 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2791 isStatic = true; 2792 2793 // This is a C++ method declaration. 2794 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2795 D.getIdentifierLoc(), Name, R, TInfo, 2796 isStatic, isInline); 2797 2798 isVirtualOkay = !isStatic; 2799 } else { 2800 // Determine whether the function was written with a 2801 // prototype. This true when: 2802 // - we're in C++ (where every function has a prototype), 2803 // - there is a prototype in the declarator, or 2804 // - the type R of the function is some kind of typedef or other reference 2805 // to a type name (which eventually refers to a function type). 2806 bool HasPrototype = 2807 getLangOptions().CPlusPlus || 2808 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2809 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2810 2811 NewFD = FunctionDecl::Create(Context, DC, 2812 D.getIdentifierLoc(), 2813 Name, R, TInfo, SC, isInline, HasPrototype); 2814 } 2815 2816 if (D.isInvalidType()) 2817 NewFD->setInvalidDecl(); 2818 2819 // Set the lexical context. If the declarator has a C++ 2820 // scope specifier, or is the object of a friend declaration, the 2821 // lexical context will be different from the semantic context. 2822 NewFD->setLexicalDeclContext(CurContext); 2823 2824 // Match up the template parameter lists with the scope specifier, then 2825 // determine whether we have a template or a template specialization. 2826 FunctionTemplateDecl *FunctionTemplate = 0; 2827 bool isExplicitSpecialization = false; 2828 bool isFunctionTemplateSpecialization = false; 2829 if (TemplateParameterList *TemplateParams 2830 = MatchTemplateParametersToScopeSpecifier( 2831 D.getDeclSpec().getSourceRange().getBegin(), 2832 D.getCXXScopeSpec(), 2833 (TemplateParameterList**)TemplateParamLists.get(), 2834 TemplateParamLists.size(), 2835 isExplicitSpecialization)) { 2836 if (TemplateParams->size() > 0) { 2837 // This is a function template 2838 2839 // Check that we can declare a template here. 2840 if (CheckTemplateDeclScope(S, TemplateParams)) 2841 return 0; 2842 2843 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2844 NewFD->getLocation(), 2845 Name, TemplateParams, 2846 NewFD); 2847 FunctionTemplate->setLexicalDeclContext(CurContext); 2848 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2849 } else { 2850 // This is a function template specialization. 2851 isFunctionTemplateSpecialization = true; 2852 } 2853 2854 // FIXME: Free this memory properly. 2855 TemplateParamLists.release(); 2856 } 2857 2858 // C++ [dcl.fct.spec]p5: 2859 // The virtual specifier shall only be used in declarations of 2860 // nonstatic class member functions that appear within a 2861 // member-specification of a class declaration; see 10.3. 2862 // 2863 if (isVirtual && !NewFD->isInvalidDecl()) { 2864 if (!isVirtualOkay) { 2865 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2866 diag::err_virtual_non_function); 2867 } else if (!CurContext->isRecord()) { 2868 // 'virtual' was specified outside of the class. 2869 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2870 << CodeModificationHint::CreateRemoval( 2871 D.getDeclSpec().getVirtualSpecLoc()); 2872 } else { 2873 // Okay: Add virtual to the method. 2874 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2875 CurClass->setMethodAsVirtual(NewFD); 2876 } 2877 } 2878 2879 // Filter out previous declarations that don't match the scope. 2880 FilterLookupForScope(*this, Previous, DC, S, NewFD->hasLinkage()); 2881 2882 if (isFriend) { 2883 // DC is the namespace in which the function is being declared. 2884 assert((DC->isFileContext() || !Previous.empty()) && 2885 "previously-undeclared friend function being created " 2886 "in a non-namespace context"); 2887 2888 if (FunctionTemplate) { 2889 FunctionTemplate->setObjectOfFriendDecl( 2890 /* PreviouslyDeclared= */ !Previous.empty()); 2891 FunctionTemplate->setAccess(AS_public); 2892 } 2893 else 2894 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ !Previous.empty()); 2895 2896 NewFD->setAccess(AS_public); 2897 } 2898 2899 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2900 !CurContext->isRecord()) { 2901 // C++ [class.static]p1: 2902 // A data or function member of a class may be declared static 2903 // in a class definition, in which case it is a static member of 2904 // the class. 2905 2906 // Complain about the 'static' specifier if it's on an out-of-line 2907 // member function definition. 2908 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2909 diag::err_static_out_of_line) 2910 << CodeModificationHint::CreateRemoval( 2911 D.getDeclSpec().getStorageClassSpecLoc()); 2912 } 2913 2914 // Handle GNU asm-label extension (encoded as an attribute). 2915 if (Expr *E = (Expr*) D.getAsmLabel()) { 2916 // The parser guarantees this is a string. 2917 StringLiteral *SE = cast<StringLiteral>(E); 2918 NewFD->addAttr(::new (Context) AsmLabelAttr(SE->getString())); 2919 } 2920 2921 // Copy the parameter declarations from the declarator D to the function 2922 // declaration NewFD, if they are available. First scavenge them into Params. 2923 llvm::SmallVector<ParmVarDecl*, 16> Params; 2924 if (D.getNumTypeObjects() > 0) { 2925 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2926 2927 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2928 // function that takes no arguments, not a function that takes a 2929 // single void argument. 2930 // We let through "const void" here because Sema::GetTypeForDeclarator 2931 // already checks for that case. 2932 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2933 FTI.ArgInfo[0].Param && 2934 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2935 // Empty arg list, don't push any params. 2936 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2937 2938 // In C++, the empty parameter-type-list must be spelled "void"; a 2939 // typedef of void is not permitted. 2940 if (getLangOptions().CPlusPlus && 2941 Param->getType().getUnqualifiedType() != Context.VoidTy) 2942 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2943 // FIXME: Leaks decl? 2944 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2945 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2946 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2947 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2948 Param->setDeclContext(NewFD); 2949 Params.push_back(Param); 2950 } 2951 } 2952 2953 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2954 // When we're declaring a function with a typedef, typeof, etc as in the 2955 // following example, we'll need to synthesize (unnamed) 2956 // parameters for use in the declaration. 2957 // 2958 // @code 2959 // typedef void fn(int); 2960 // fn f; 2961 // @endcode 2962 2963 // Synthesize a parameter for each argument type. 2964 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2965 AE = FT->arg_type_end(); AI != AE; ++AI) { 2966 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2967 SourceLocation(), 0, 2968 *AI, /*TInfo=*/0, 2969 VarDecl::None, 0); 2970 Param->setImplicit(); 2971 Params.push_back(Param); 2972 } 2973 } else { 2974 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2975 "Should not need args for typedef of non-prototype fn"); 2976 } 2977 // Finally, we know we have the right number of parameters, install them. 2978 NewFD->setParams(Context, Params.data(), Params.size()); 2979 2980 // If the declarator is a template-id, translate the parser's template 2981 // argument list into our AST format. 2982 bool HasExplicitTemplateArgs = false; 2983 TemplateArgumentListInfo TemplateArgs; 2984 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2985 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2986 TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc); 2987 TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc); 2988 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2989 TemplateId->getTemplateArgs(), 2990 TemplateId->NumArgs); 2991 translateTemplateArguments(TemplateArgsPtr, 2992 TemplateArgs); 2993 TemplateArgsPtr.release(); 2994 2995 HasExplicitTemplateArgs = true; 2996 2997 if (FunctionTemplate) { 2998 // FIXME: Diagnose function template with explicit template 2999 // arguments. 3000 HasExplicitTemplateArgs = false; 3001 } else if (!isFunctionTemplateSpecialization && 3002 !D.getDeclSpec().isFriendSpecified()) { 3003 // We have encountered something that the user meant to be a 3004 // specialization (because it has explicitly-specified template 3005 // arguments) but that was not introduced with a "template<>" (or had 3006 // too few of them). 3007 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 3008 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 3009 << CodeModificationHint::CreateInsertion( 3010 D.getDeclSpec().getSourceRange().getBegin(), 3011 "template<> "); 3012 isFunctionTemplateSpecialization = true; 3013 } 3014 } 3015 3016 if (isFunctionTemplateSpecialization) { 3017 if (CheckFunctionTemplateSpecialization(NewFD, 3018 (HasExplicitTemplateArgs ? &TemplateArgs : 0), 3019 Previous)) 3020 NewFD->setInvalidDecl(); 3021 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 3022 CheckMemberSpecialization(NewFD, Previous)) 3023 NewFD->setInvalidDecl(); 3024 3025 // Perform semantic checking on the function declaration. 3026 bool OverloadableAttrRequired = false; // FIXME: HACK! 3027 CheckFunctionDeclaration(S, NewFD, Previous, isExplicitSpecialization, 3028 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 3029 3030 assert((NewFD->isInvalidDecl() || !Redeclaration || 3031 Previous.getResultKind() != LookupResult::FoundOverloaded) && 3032 "previous declaration set still overloaded"); 3033 3034 // If we have a function template, check the template parameter 3035 // list. This will check and merge default template arguments. 3036 if (FunctionTemplate) { 3037 FunctionTemplateDecl *PrevTemplate = FunctionTemplate->getPreviousDeclaration(); 3038 CheckTemplateParameterList(FunctionTemplate->getTemplateParameters(), 3039 PrevTemplate? PrevTemplate->getTemplateParameters() : 0, 3040 D.getDeclSpec().isFriendSpecified()? TPC_FriendFunctionTemplate 3041 : TPC_FunctionTemplate); 3042 } 3043 3044 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 3045 // An out-of-line member function declaration must also be a 3046 // definition (C++ [dcl.meaning]p1). 3047 // Note that this is not the case for explicit specializations of 3048 // function templates or member functions of class templates, per 3049 // C++ [temp.expl.spec]p2. 3050 if (!IsFunctionDefinition && !isFriend && 3051 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 3052 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 3053 << D.getCXXScopeSpec().getRange(); 3054 NewFD->setInvalidDecl(); 3055 } else if (!Redeclaration) { 3056 // The user tried to provide an out-of-line definition for a 3057 // function that is a member of a class or namespace, but there 3058 // was no such member function declared (C++ [class.mfct]p2, 3059 // C++ [namespace.memdef]p2). For example: 3060 // 3061 // class X { 3062 // void f() const; 3063 // }; 3064 // 3065 // void X::f() { } // ill-formed 3066 // 3067 // Complain about this problem, and attempt to suggest close 3068 // matches (e.g., those that differ only in cv-qualifiers and 3069 // whether the parameter types are references). 3070 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 3071 << Name << DC << D.getCXXScopeSpec().getRange(); 3072 NewFD->setInvalidDecl(); 3073 3074 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 3075 ForRedeclaration); 3076 LookupQualifiedName(Prev, DC); 3077 assert(!Prev.isAmbiguous() && 3078 "Cannot have an ambiguity in previous-declaration lookup"); 3079 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 3080 Func != FuncEnd; ++Func) { 3081 if (isa<FunctionDecl>(*Func) && 3082 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 3083 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 3084 } 3085 } 3086 } 3087 3088 // Handle attributes. We need to have merged decls when handling attributes 3089 // (for example to check for conflicts, etc). 3090 // FIXME: This needs to happen before we merge declarations. Then, 3091 // let attribute merging cope with attribute conflicts. 3092 ProcessDeclAttributes(S, NewFD, D); 3093 3094 // attributes declared post-definition are currently ignored 3095 if (Redeclaration && Previous.isSingleResult()) { 3096 const FunctionDecl *Def; 3097 FunctionDecl *PrevFD = dyn_cast<FunctionDecl>(Previous.getFoundDecl()); 3098 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 3099 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 3100 Diag(Def->getLocation(), diag::note_previous_definition); 3101 } 3102 } 3103 3104 AddKnownFunctionAttributes(NewFD); 3105 3106 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 3107 // If a function name is overloadable in C, then every function 3108 // with that name must be marked "overloadable". 3109 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 3110 << Redeclaration << NewFD; 3111 if (!Previous.empty()) 3112 Diag(Previous.getRepresentativeDecl()->getLocation(), 3113 diag::note_attribute_overloadable_prev_overload); 3114 NewFD->addAttr(::new (Context) OverloadableAttr()); 3115 } 3116 3117 // If this is a locally-scoped extern C function, update the 3118 // map of such names. 3119 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 3120 && !NewFD->isInvalidDecl()) 3121 RegisterLocallyScopedExternCDecl(NewFD, Previous, S); 3122 3123 // Set this FunctionDecl's range up to the right paren. 3124 NewFD->setLocEnd(D.getSourceRange().getEnd()); 3125 3126 if (FunctionTemplate && NewFD->isInvalidDecl()) 3127 FunctionTemplate->setInvalidDecl(); 3128 3129 if (FunctionTemplate) 3130 return FunctionTemplate; 3131 3132 return NewFD; 3133} 3134 3135/// \brief Perform semantic checking of a new function declaration. 3136/// 3137/// Performs semantic analysis of the new function declaration 3138/// NewFD. This routine performs all semantic checking that does not 3139/// require the actual declarator involved in the declaration, and is 3140/// used both for the declaration of functions as they are parsed 3141/// (called via ActOnDeclarator) and for the declaration of functions 3142/// that have been instantiated via C++ template instantiation (called 3143/// via InstantiateDecl). 3144/// 3145/// \param IsExplicitSpecialiation whether this new function declaration is 3146/// an explicit specialization of the previous declaration. 3147/// 3148/// This sets NewFD->isInvalidDecl() to true if there was an error. 3149void Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD, 3150 LookupResult &Previous, 3151 bool IsExplicitSpecialization, 3152 bool &Redeclaration, 3153 bool &OverloadableAttrRequired) { 3154 // If NewFD is already known erroneous, don't do any of this checking. 3155 if (NewFD->isInvalidDecl()) 3156 return; 3157 3158 if (NewFD->getResultType()->isVariablyModifiedType()) { 3159 // Functions returning a variably modified type violate C99 6.7.5.2p2 3160 // because all functions have linkage. 3161 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3162 return NewFD->setInvalidDecl(); 3163 } 3164 3165 if (NewFD->isMain()) 3166 CheckMain(NewFD); 3167 3168 // Check for a previous declaration of this name. 3169 if (Previous.empty() && NewFD->isExternC()) { 3170 // Since we did not find anything by this name and we're declaring 3171 // an extern "C" function, look for a non-visible extern "C" 3172 // declaration with the same name. 3173 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3174 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3175 if (Pos != LocallyScopedExternalDecls.end()) 3176 Previous.addDecl(Pos->second); 3177 } 3178 3179 // Merge or overload the declaration with an existing declaration of 3180 // the same name, if appropriate. 3181 if (!Previous.empty()) { 3182 // Determine whether NewFD is an overload of PrevDecl or 3183 // a declaration that requires merging. If it's an overload, 3184 // there's no more work to do here; we'll just add the new 3185 // function to the scope. 3186 3187 NamedDecl *OldDecl = 0; 3188 if (!AllowOverloadingOfFunction(Previous, Context)) { 3189 Redeclaration = true; 3190 OldDecl = Previous.getFoundDecl(); 3191 } else { 3192 if (!getLangOptions().CPlusPlus) { 3193 OverloadableAttrRequired = true; 3194 3195 // Functions marked "overloadable" must have a prototype (that 3196 // we can't get through declaration merging). 3197 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3198 Diag(NewFD->getLocation(), 3199 diag::err_attribute_overloadable_no_prototype) 3200 << NewFD; 3201 Redeclaration = true; 3202 3203 // Turn this into a variadic function with no parameters. 3204 QualType R = Context.getFunctionType( 3205 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3206 0, 0, true, 0); 3207 NewFD->setType(R); 3208 return NewFD->setInvalidDecl(); 3209 } 3210 } 3211 3212 switch (CheckOverload(NewFD, Previous, OldDecl)) { 3213 case Ovl_Match: 3214 Redeclaration = true; 3215 if (isa<UsingShadowDecl>(OldDecl) && CurContext->isRecord()) { 3216 HideUsingShadowDecl(S, cast<UsingShadowDecl>(OldDecl)); 3217 Redeclaration = false; 3218 } 3219 break; 3220 3221 case Ovl_NonFunction: 3222 Redeclaration = true; 3223 break; 3224 3225 case Ovl_Overload: 3226 Redeclaration = false; 3227 break; 3228 } 3229 } 3230 3231 if (Redeclaration) { 3232 // NewFD and OldDecl represent declarations that need to be 3233 // merged. 3234 if (MergeFunctionDecl(NewFD, OldDecl)) 3235 return NewFD->setInvalidDecl(); 3236 3237 Previous.clear(); 3238 Previous.addDecl(OldDecl); 3239 3240 if (FunctionTemplateDecl *OldTemplateDecl 3241 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3242 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3243 FunctionTemplateDecl *NewTemplateDecl 3244 = NewFD->getDescribedFunctionTemplate(); 3245 assert(NewTemplateDecl && "Template/non-template mismatch"); 3246 if (CXXMethodDecl *Method 3247 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3248 Method->setAccess(OldTemplateDecl->getAccess()); 3249 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3250 } 3251 3252 // If this is an explicit specialization of a member that is a function 3253 // template, mark it as a member specialization. 3254 if (IsExplicitSpecialization && 3255 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3256 NewTemplateDecl->setMemberSpecialization(); 3257 assert(OldTemplateDecl->isMemberSpecialization()); 3258 } 3259 } else { 3260 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3261 NewFD->setAccess(OldDecl->getAccess()); 3262 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3263 } 3264 } 3265 } 3266 3267 // Semantic checking for this function declaration (in isolation). 3268 if (getLangOptions().CPlusPlus) { 3269 // C++-specific checks. 3270 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3271 CheckConstructor(Constructor); 3272 } else if (CXXDestructorDecl *Destructor = 3273 dyn_cast<CXXDestructorDecl>(NewFD)) { 3274 CXXRecordDecl *Record = Destructor->getParent(); 3275 QualType ClassType = Context.getTypeDeclType(Record); 3276 3277 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3278 // type is dependent? Both gcc and edg can handle that. 3279 if (!ClassType->isDependentType()) { 3280 DeclarationName Name 3281 = Context.DeclarationNames.getCXXDestructorName( 3282 Context.getCanonicalType(ClassType)); 3283 if (NewFD->getDeclName() != Name) { 3284 Diag(NewFD->getLocation(), diag::err_destructor_name); 3285 return NewFD->setInvalidDecl(); 3286 } 3287 } 3288 3289 Record->setUserDeclaredDestructor(true); 3290 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3291 // user-defined destructor. 3292 Record->setPOD(false); 3293 3294 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3295 // declared destructor. 3296 // FIXME: C++0x: don't do this for "= default" destructors 3297 Record->setHasTrivialDestructor(false); 3298 } else if (CXXConversionDecl *Conversion 3299 = dyn_cast<CXXConversionDecl>(NewFD)) { 3300 ActOnConversionDeclarator(Conversion); 3301 } 3302 3303 // Find any virtual functions that this function overrides. 3304 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD)) { 3305 if (!Method->isFunctionTemplateSpecialization() && 3306 !Method->getDescribedFunctionTemplate()) 3307 AddOverriddenMethods(Method->getParent(), Method); 3308 } 3309 3310 // Additional checks for the destructor; make sure we do this after we 3311 // figure out whether the destructor is virtual. 3312 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(NewFD)) 3313 if (!Destructor->getParent()->isDependentType()) 3314 CheckDestructor(Destructor); 3315 3316 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3317 if (NewFD->isOverloadedOperator() && 3318 CheckOverloadedOperatorDeclaration(NewFD)) 3319 return NewFD->setInvalidDecl(); 3320 3321 // In C++, check default arguments now that we have merged decls. Unless 3322 // the lexical context is the class, because in this case this is done 3323 // during delayed parsing anyway. 3324 if (!CurContext->isRecord()) 3325 CheckCXXDefaultArguments(NewFD); 3326 } 3327} 3328 3329void Sema::CheckMain(FunctionDecl* FD) { 3330 // C++ [basic.start.main]p3: A program that declares main to be inline 3331 // or static is ill-formed. 3332 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3333 // shall not appear in a declaration of main. 3334 // static main is not an error under C99, but we should warn about it. 3335 bool isInline = FD->isInlineSpecified(); 3336 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3337 if (isInline || isStatic) { 3338 unsigned diagID = diag::warn_unusual_main_decl; 3339 if (isInline || getLangOptions().CPlusPlus) 3340 diagID = diag::err_unusual_main_decl; 3341 3342 int which = isStatic + (isInline << 1) - 1; 3343 Diag(FD->getLocation(), diagID) << which; 3344 } 3345 3346 QualType T = FD->getType(); 3347 assert(T->isFunctionType() && "function decl is not of function type"); 3348 const FunctionType* FT = T->getAs<FunctionType>(); 3349 3350 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3351 // TODO: add a replacement fixit to turn the return type into 'int'. 3352 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3353 FD->setInvalidDecl(true); 3354 } 3355 3356 // Treat protoless main() as nullary. 3357 if (isa<FunctionNoProtoType>(FT)) return; 3358 3359 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3360 unsigned nparams = FTP->getNumArgs(); 3361 assert(FD->getNumParams() == nparams); 3362 3363 if (nparams > 3) { 3364 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3365 FD->setInvalidDecl(true); 3366 nparams = 3; 3367 } 3368 3369 // FIXME: a lot of the following diagnostics would be improved 3370 // if we had some location information about types. 3371 3372 QualType CharPP = 3373 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3374 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3375 3376 for (unsigned i = 0; i < nparams; ++i) { 3377 QualType AT = FTP->getArgType(i); 3378 3379 bool mismatch = true; 3380 3381 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3382 mismatch = false; 3383 else if (Expected[i] == CharPP) { 3384 // As an extension, the following forms are okay: 3385 // char const ** 3386 // char const * const * 3387 // char * const * 3388 3389 QualifierCollector qs; 3390 const PointerType* PT; 3391 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3392 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3393 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3394 qs.removeConst(); 3395 mismatch = !qs.empty(); 3396 } 3397 } 3398 3399 if (mismatch) { 3400 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3401 // TODO: suggest replacing given type with expected type 3402 FD->setInvalidDecl(true); 3403 } 3404 } 3405 3406 if (nparams == 1 && !FD->isInvalidDecl()) { 3407 Diag(FD->getLocation(), diag::warn_main_one_arg); 3408 } 3409} 3410 3411bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3412 // FIXME: Need strict checking. In C89, we need to check for 3413 // any assignment, increment, decrement, function-calls, or 3414 // commas outside of a sizeof. In C99, it's the same list, 3415 // except that the aforementioned are allowed in unevaluated 3416 // expressions. Everything else falls under the 3417 // "may accept other forms of constant expressions" exception. 3418 // (We never end up here for C++, so the constant expression 3419 // rules there don't matter.) 3420 if (Init->isConstantInitializer(Context)) 3421 return false; 3422 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3423 << Init->getSourceRange(); 3424 return true; 3425} 3426 3427void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3428 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3429} 3430 3431/// AddInitializerToDecl - Adds the initializer Init to the 3432/// declaration dcl. If DirectInit is true, this is C++ direct 3433/// initialization rather than copy initialization. 3434void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3435 Decl *RealDecl = dcl.getAs<Decl>(); 3436 // If there is no declaration, there was an error parsing it. Just ignore 3437 // the initializer. 3438 if (RealDecl == 0) 3439 return; 3440 3441 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3442 // With declarators parsed the way they are, the parser cannot 3443 // distinguish between a normal initializer and a pure-specifier. 3444 // Thus this grotesque test. 3445 IntegerLiteral *IL; 3446 Expr *Init = static_cast<Expr *>(init.get()); 3447 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3448 Context.getCanonicalType(IL->getType()) == Context.IntTy) 3449 CheckPureMethod(Method, Init->getSourceRange()); 3450 else { 3451 Diag(Method->getLocation(), diag::err_member_function_initialization) 3452 << Method->getDeclName() << Init->getSourceRange(); 3453 Method->setInvalidDecl(); 3454 } 3455 return; 3456 } 3457 3458 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3459 if (!VDecl) { 3460 if (getLangOptions().CPlusPlus && 3461 RealDecl->getLexicalDeclContext()->isRecord() && 3462 isa<NamedDecl>(RealDecl)) 3463 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3464 << cast<NamedDecl>(RealDecl)->getDeclName(); 3465 else 3466 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3467 RealDecl->setInvalidDecl(); 3468 return; 3469 } 3470 3471 // A definition must end up with a complete type, which means it must be 3472 // complete with the restriction that an array type might be completed by the 3473 // initializer; note that later code assumes this restriction. 3474 QualType BaseDeclType = VDecl->getType(); 3475 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3476 BaseDeclType = Array->getElementType(); 3477 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3478 diag::err_typecheck_decl_incomplete_type)) { 3479 RealDecl->setInvalidDecl(); 3480 return; 3481 } 3482 3483 // The variable can not have an abstract class type. 3484 if (RequireNonAbstractType(VDecl->getLocation(), VDecl->getType(), 3485 diag::err_abstract_type_in_decl, 3486 AbstractVariableType)) 3487 VDecl->setInvalidDecl(); 3488 3489 const VarDecl *Def = 0; 3490 if (VDecl->getDefinition(Def)) { 3491 Diag(VDecl->getLocation(), diag::err_redefinition) 3492 << VDecl->getDeclName(); 3493 Diag(Def->getLocation(), diag::note_previous_definition); 3494 VDecl->setInvalidDecl(); 3495 return; 3496 } 3497 3498 // Take ownership of the expression, now that we're sure we have somewhere 3499 // to put it. 3500 Expr *Init = init.takeAs<Expr>(); 3501 assert(Init && "missing initializer"); 3502 3503 // Get the decls type and save a reference for later, since 3504 // CheckInitializerTypes may change it. 3505 QualType DclT = VDecl->getType(), SavT = DclT; 3506 if (VDecl->isBlockVarDecl()) { 3507 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3508 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3509 VDecl->setInvalidDecl(); 3510 } else if (!VDecl->isInvalidDecl()) { 3511 if (VDecl->getType()->isReferenceType() 3512 || isa<InitListExpr>(Init)) { 3513 InitializedEntity Entity 3514 = InitializedEntity::InitializeVariable(VDecl); 3515 3516 // FIXME: Poor source location information. 3517 InitializationKind Kind 3518 = DirectInit? InitializationKind::CreateDirect(VDecl->getLocation(), 3519 SourceLocation(), 3520 SourceLocation()) 3521 : InitializationKind::CreateCopy(VDecl->getLocation(), 3522 SourceLocation()); 3523 InitializationSequence InitSeq(*this, Entity, Kind, &Init, 1); 3524 if (InitSeq) { 3525 OwningExprResult Result = InitSeq.Perform(*this, Entity, Kind, 3526 MultiExprArg(*this, (void**)&Init, 1), 3527 &DclT); 3528 if (Result.isInvalid()) { 3529 VDecl->setInvalidDecl(); 3530 return; 3531 } 3532 3533 Init = Result.takeAs<Expr>(); 3534 } else { 3535 InitSeq.Diagnose(*this, Entity, Kind, &Init, 1); 3536 VDecl->setInvalidDecl(); 3537 return; 3538 } 3539 } else if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3540 VDecl->getDeclName(), DirectInit)) 3541 VDecl->setInvalidDecl(); 3542 3543 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3544 // Don't check invalid declarations to avoid emitting useless diagnostics. 3545 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3546 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3547 CheckForConstantInitializer(Init, DclT); 3548 } 3549 } 3550 } else if (VDecl->isStaticDataMember() && 3551 VDecl->getLexicalDeclContext()->isRecord()) { 3552 // This is an in-class initialization for a static data member, e.g., 3553 // 3554 // struct S { 3555 // static const int value = 17; 3556 // }; 3557 3558 // Attach the initializer 3559 VDecl->setInit(Context, Init); 3560 3561 // C++ [class.mem]p4: 3562 // A member-declarator can contain a constant-initializer only 3563 // if it declares a static member (9.4) of const integral or 3564 // const enumeration type, see 9.4.2. 3565 QualType T = VDecl->getType(); 3566 if (!T->isDependentType() && 3567 (!Context.getCanonicalType(T).isConstQualified() || 3568 !T->isIntegralType())) { 3569 Diag(VDecl->getLocation(), diag::err_member_initialization) 3570 << VDecl->getDeclName() << Init->getSourceRange(); 3571 VDecl->setInvalidDecl(); 3572 } else { 3573 // C++ [class.static.data]p4: 3574 // If a static data member is of const integral or const 3575 // enumeration type, its declaration in the class definition 3576 // can specify a constant-initializer which shall be an 3577 // integral constant expression (5.19). 3578 if (!Init->isTypeDependent() && 3579 !Init->getType()->isIntegralType()) { 3580 // We have a non-dependent, non-integral or enumeration type. 3581 Diag(Init->getSourceRange().getBegin(), 3582 diag::err_in_class_initializer_non_integral_type) 3583 << Init->getType() << Init->getSourceRange(); 3584 VDecl->setInvalidDecl(); 3585 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3586 // Check whether the expression is a constant expression. 3587 llvm::APSInt Value; 3588 SourceLocation Loc; 3589 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3590 Diag(Loc, diag::err_in_class_initializer_non_constant) 3591 << Init->getSourceRange(); 3592 VDecl->setInvalidDecl(); 3593 } else if (!VDecl->getType()->isDependentType()) 3594 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3595 } 3596 } 3597 } else if (VDecl->isFileVarDecl()) { 3598 if (VDecl->getStorageClass() == VarDecl::Extern) 3599 Diag(VDecl->getLocation(), diag::warn_extern_init); 3600 if (!VDecl->isInvalidDecl()) 3601 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3602 VDecl->getDeclName(), DirectInit)) 3603 VDecl->setInvalidDecl(); 3604 3605 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3606 // Don't check invalid declarations to avoid emitting useless diagnostics. 3607 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3608 // C99 6.7.8p4. All file scoped initializers need to be constant. 3609 CheckForConstantInitializer(Init, DclT); 3610 } 3611 } 3612 // If the type changed, it means we had an incomplete type that was 3613 // completed by the initializer. For example: 3614 // int ary[] = { 1, 3, 5 }; 3615 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3616 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3617 VDecl->setType(DclT); 3618 Init->setType(DclT); 3619 } 3620 3621 Init = MaybeCreateCXXExprWithTemporaries(Init, 3622 /*ShouldDestroyTemporaries=*/true); 3623 // Attach the initializer to the decl. 3624 VDecl->setInit(Context, Init); 3625 3626 // If the previous declaration of VDecl was a tentative definition, 3627 // remove it from the set of tentative definitions. 3628 if (VDecl->getPreviousDeclaration() && 3629 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3630 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3631 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3632 } 3633 3634 return; 3635} 3636 3637void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3638 bool TypeContainsUndeducedAuto) { 3639 Decl *RealDecl = dcl.getAs<Decl>(); 3640 3641 // If there is no declaration, there was an error parsing it. Just ignore it. 3642 if (RealDecl == 0) 3643 return; 3644 3645 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3646 QualType Type = Var->getType(); 3647 3648 // Record tentative definitions. 3649 if (Var->isTentativeDefinition(Context)) { 3650 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3651 InsertPair = 3652 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3653 3654 // Keep the latest definition in the map. If we see 'int i; int i;' we 3655 // want the second one in the map. 3656 InsertPair.first->second = Var; 3657 3658 // However, for the list, we don't care about the order, just make sure 3659 // that there are no dupes for a given declaration name. 3660 if (InsertPair.second) 3661 TentativeDefinitionList.push_back(Var->getDeclName()); 3662 } 3663 3664 // C++ [dcl.init.ref]p3: 3665 // The initializer can be omitted for a reference only in a 3666 // parameter declaration (8.3.5), in the declaration of a 3667 // function return type, in the declaration of a class member 3668 // within its class declaration (9.2), and where the extern 3669 // specifier is explicitly used. 3670 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3671 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3672 << Var->getDeclName() 3673 << SourceRange(Var->getLocation(), Var->getLocation()); 3674 Var->setInvalidDecl(); 3675 return; 3676 } 3677 3678 // C++0x [dcl.spec.auto]p3 3679 if (TypeContainsUndeducedAuto) { 3680 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3681 << Var->getDeclName() << Type; 3682 Var->setInvalidDecl(); 3683 return; 3684 } 3685 3686 // An array without size is an incomplete type, and there are no special 3687 // rules in C++ to make such a definition acceptable. 3688 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3689 !Var->hasExternalStorage()) { 3690 Diag(Var->getLocation(), 3691 diag::err_typecheck_incomplete_array_needs_initializer); 3692 Var->setInvalidDecl(); 3693 return; 3694 } 3695 3696 // C++ [temp.expl.spec]p15: 3697 // An explicit specialization of a static data member of a template is a 3698 // definition if the declaration includes an initializer; otherwise, it 3699 // is a declaration. 3700 if (Var->isStaticDataMember() && 3701 Var->getInstantiatedFromStaticDataMember() && 3702 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3703 return; 3704 3705 // C++ [dcl.init]p9: 3706 // If no initializer is specified for an object, and the object 3707 // is of (possibly cv-qualified) non-POD class type (or array 3708 // thereof), the object shall be default-initialized; if the 3709 // object is of const-qualified type, the underlying class type 3710 // shall have a user-declared default constructor. 3711 // 3712 // FIXME: Diagnose the "user-declared default constructor" bit. 3713 if (getLangOptions().CPlusPlus) { 3714 QualType InitType = Type; 3715 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3716 InitType = Context.getBaseElementType(Array); 3717 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3718 InitType->isRecordType() && !InitType->isDependentType()) { 3719 if (!RequireCompleteType(Var->getLocation(), InitType, 3720 diag::err_invalid_incomplete_type_use)) { 3721 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3722 3723 CXXConstructorDecl *Constructor 3724 = PerformInitializationByConstructor(InitType, 3725 MultiExprArg(*this, 0, 0), 3726 Var->getLocation(), 3727 SourceRange(Var->getLocation(), 3728 Var->getLocation()), 3729 Var->getDeclName(), 3730 InitializationKind::CreateDefault(Var->getLocation()), 3731 ConstructorArgs); 3732 3733 // FIXME: Location info for the variable initialization? 3734 if (!Constructor) 3735 Var->setInvalidDecl(); 3736 else { 3737 // FIXME: Cope with initialization of arrays 3738 if (!Constructor->isTrivial() && 3739 InitializeVarWithConstructor(Var, Constructor, 3740 move_arg(ConstructorArgs))) 3741 Var->setInvalidDecl(); 3742 3743 FinalizeVarWithDestructor(Var, InitType); 3744 } 3745 } else { 3746 Var->setInvalidDecl(); 3747 } 3748 } 3749 3750 // The variable can not have an abstract class type. 3751 if (RequireNonAbstractType(Var->getLocation(), Type, 3752 diag::err_abstract_type_in_decl, 3753 AbstractVariableType)) 3754 Var->setInvalidDecl(); 3755 } 3756 3757#if 0 3758 // FIXME: Temporarily disabled because we are not properly parsing 3759 // linkage specifications on declarations, e.g., 3760 // 3761 // extern "C" const CGPoint CGPointerZero; 3762 // 3763 // C++ [dcl.init]p9: 3764 // 3765 // If no initializer is specified for an object, and the 3766 // object is of (possibly cv-qualified) non-POD class type (or 3767 // array thereof), the object shall be default-initialized; if 3768 // the object is of const-qualified type, the underlying class 3769 // type shall have a user-declared default 3770 // constructor. Otherwise, if no initializer is specified for 3771 // an object, the object and its subobjects, if any, have an 3772 // indeterminate initial value; if the object or any of its 3773 // subobjects are of const-qualified type, the program is 3774 // ill-formed. 3775 // 3776 // This isn't technically an error in C, so we don't diagnose it. 3777 // 3778 // FIXME: Actually perform the POD/user-defined default 3779 // constructor check. 3780 if (getLangOptions().CPlusPlus && 3781 Context.getCanonicalType(Type).isConstQualified() && 3782 !Var->hasExternalStorage()) 3783 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3784 << Var->getName() 3785 << SourceRange(Var->getLocation(), Var->getLocation()); 3786#endif 3787 } 3788} 3789 3790Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3791 DeclPtrTy *Group, 3792 unsigned NumDecls) { 3793 llvm::SmallVector<Decl*, 8> Decls; 3794 3795 if (DS.isTypeSpecOwned()) 3796 Decls.push_back((Decl*)DS.getTypeRep()); 3797 3798 for (unsigned i = 0; i != NumDecls; ++i) 3799 if (Decl *D = Group[i].getAs<Decl>()) 3800 Decls.push_back(D); 3801 3802 // Perform semantic analysis that depends on having fully processed both 3803 // the declarator and initializer. 3804 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3805 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3806 if (!IDecl) 3807 continue; 3808 QualType T = IDecl->getType(); 3809 3810 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3811 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3812 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3813 if (T->isDependentType()) { 3814 // If T is dependent, we should not require a complete type. 3815 // (RequireCompleteType shouldn't be called with dependent types.) 3816 // But we still can at least check if we've got an array of unspecified 3817 // size without an initializer. 3818 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3819 !IDecl->getInit()) { 3820 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3821 << T; 3822 IDecl->setInvalidDecl(); 3823 } 3824 } else if (!IDecl->isInvalidDecl()) { 3825 // If T is an incomplete array type with an initializer list that is 3826 // dependent on something, its size has not been fixed. We could attempt 3827 // to fix the size for such arrays, but we would still have to check 3828 // here for initializers containing a C++0x vararg expansion, e.g. 3829 // template <typename... Args> void f(Args... args) { 3830 // int vals[] = { args }; 3831 // } 3832 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3833 Expr *Init = IDecl->getInit(); 3834 if (IAT && Init && 3835 (Init->isTypeDependent() || Init->isValueDependent())) { 3836 // Check that the member type of the array is complete, at least. 3837 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3838 diag::err_typecheck_decl_incomplete_type)) 3839 IDecl->setInvalidDecl(); 3840 } else if (RequireCompleteType(IDecl->getLocation(), T, 3841 diag::err_typecheck_decl_incomplete_type)) 3842 IDecl->setInvalidDecl(); 3843 } 3844 } 3845 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3846 // object that has file scope without an initializer, and without a 3847 // storage-class specifier or with the storage-class specifier "static", 3848 // constitutes a tentative definition. Note: A tentative definition with 3849 // external linkage is valid (C99 6.2.2p5). 3850 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3851 if (const IncompleteArrayType *ArrayT 3852 = Context.getAsIncompleteArrayType(T)) { 3853 if (RequireCompleteType(IDecl->getLocation(), 3854 ArrayT->getElementType(), 3855 diag::err_illegal_decl_array_incomplete_type)) 3856 IDecl->setInvalidDecl(); 3857 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3858 // C99 6.9.2p3: If the declaration of an identifier for an object is 3859 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3860 // declared type shall not be an incomplete type. 3861 // NOTE: code such as the following 3862 // static struct s; 3863 // struct s { int a; }; 3864 // is accepted by gcc. Hence here we issue a warning instead of 3865 // an error and we do not invalidate the static declaration. 3866 // NOTE: to avoid multiple warnings, only check the first declaration. 3867 if (IDecl->getPreviousDeclaration() == 0) 3868 RequireCompleteType(IDecl->getLocation(), T, 3869 diag::ext_typecheck_decl_incomplete_type); 3870 } 3871 } 3872 } 3873 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3874 Decls.data(), Decls.size())); 3875} 3876 3877 3878/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3879/// to introduce parameters into function prototype scope. 3880Sema::DeclPtrTy 3881Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3882 const DeclSpec &DS = D.getDeclSpec(); 3883 3884 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3885 VarDecl::StorageClass StorageClass = VarDecl::None; 3886 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3887 StorageClass = VarDecl::Register; 3888 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3889 Diag(DS.getStorageClassSpecLoc(), 3890 diag::err_invalid_storage_class_in_func_decl); 3891 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3892 } 3893 3894 if (D.getDeclSpec().isThreadSpecified()) 3895 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3896 3897 DiagnoseFunctionSpecifiers(D); 3898 3899 // Check that there are no default arguments inside the type of this 3900 // parameter (C++ only). 3901 if (getLangOptions().CPlusPlus) 3902 CheckExtraCXXDefaultArguments(D); 3903 3904 TypeSourceInfo *TInfo = 0; 3905 TagDecl *OwnedDecl = 0; 3906 QualType parmDeclType = GetTypeForDeclarator(D, S, &TInfo, &OwnedDecl); 3907 3908 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3909 // C++ [dcl.fct]p6: 3910 // Types shall not be defined in return or parameter types. 3911 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3912 << Context.getTypeDeclType(OwnedDecl); 3913 } 3914 3915 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3916 // Can this happen for params? We already checked that they don't conflict 3917 // among each other. Here they can only shadow globals, which is ok. 3918 IdentifierInfo *II = D.getIdentifier(); 3919 if (II) { 3920 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3921 if (PrevDecl->isTemplateParameter()) { 3922 // Maybe we will complain about the shadowed template parameter. 3923 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3924 // Just pretend that we didn't see the previous declaration. 3925 PrevDecl = 0; 3926 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3927 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3928 3929 // Recover by removing the name 3930 II = 0; 3931 D.SetIdentifier(0, D.getIdentifierLoc()); 3932 } 3933 } 3934 } 3935 3936 // Parameters can not be abstract class types. 3937 // For record types, this is done by the AbstractClassUsageDiagnoser once 3938 // the class has been completely parsed. 3939 if (!CurContext->isRecord() && 3940 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3941 diag::err_abstract_type_in_decl, 3942 AbstractParamType)) 3943 D.setInvalidType(true); 3944 3945 QualType T = adjustParameterType(parmDeclType); 3946 3947 ParmVarDecl *New 3948 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3949 T, TInfo, StorageClass, 0); 3950 3951 if (D.isInvalidType()) 3952 New->setInvalidDecl(); 3953 3954 // Parameter declarators cannot be interface types. All ObjC objects are 3955 // passed by reference. 3956 if (T->isObjCInterfaceType()) { 3957 Diag(D.getIdentifierLoc(), 3958 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3959 New->setInvalidDecl(); 3960 } 3961 3962 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3963 if (D.getCXXScopeSpec().isSet()) { 3964 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3965 << D.getCXXScopeSpec().getRange(); 3966 New->setInvalidDecl(); 3967 } 3968 3969 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3970 // duration shall not be qualified by an address-space qualifier." 3971 // Since all parameters have automatic store duration, they can not have 3972 // an address space. 3973 if (T.getAddressSpace() != 0) { 3974 Diag(D.getIdentifierLoc(), 3975 diag::err_arg_with_address_space); 3976 New->setInvalidDecl(); 3977 } 3978 3979 3980 // Add the parameter declaration into this scope. 3981 S->AddDecl(DeclPtrTy::make(New)); 3982 if (II) 3983 IdResolver.AddDecl(New); 3984 3985 ProcessDeclAttributes(S, New, D); 3986 3987 if (New->hasAttr<BlocksAttr>()) { 3988 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3989 } 3990 return DeclPtrTy::make(New); 3991} 3992 3993void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3994 SourceLocation LocAfterDecls) { 3995 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3996 "Not a function declarator!"); 3997 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3998 3999 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 4000 // for a K&R function. 4001 if (!FTI.hasPrototype) { 4002 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 4003 --i; 4004 if (FTI.ArgInfo[i].Param == 0) { 4005 llvm::SmallString<256> Code; 4006 llvm::raw_svector_ostream(Code) << " int " 4007 << FTI.ArgInfo[i].Ident->getName() 4008 << ";\n"; 4009 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 4010 << FTI.ArgInfo[i].Ident 4011 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 4012 4013 // Implicitly declare the argument as type 'int' for lack of a better 4014 // type. 4015 DeclSpec DS; 4016 const char* PrevSpec; // unused 4017 unsigned DiagID; // unused 4018 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 4019 PrevSpec, DiagID); 4020 Declarator ParamD(DS, Declarator::KNRTypeListContext); 4021 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 4022 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 4023 } 4024 } 4025 } 4026} 4027 4028Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 4029 Declarator &D) { 4030 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 4031 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 4032 "Not a function declarator!"); 4033 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 4034 4035 if (FTI.hasPrototype) { 4036 // FIXME: Diagnose arguments without names in C. 4037 } 4038 4039 Scope *ParentScope = FnBodyScope->getParent(); 4040 4041 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 4042 MultiTemplateParamsArg(*this), 4043 /*IsFunctionDefinition=*/true); 4044 return ActOnStartOfFunctionDef(FnBodyScope, DP); 4045} 4046 4047static bool ShouldWarnAboutMissingPrototype(const FunctionDecl *FD) { 4048 // Don't warn about invalid declarations. 4049 if (FD->isInvalidDecl()) 4050 return false; 4051 4052 // Or declarations that aren't global. 4053 if (!FD->isGlobal()) 4054 return false; 4055 4056 // Don't warn about C++ member functions. 4057 if (isa<CXXMethodDecl>(FD)) 4058 return false; 4059 4060 // Don't warn about 'main'. 4061 if (FD->isMain()) 4062 return false; 4063 4064 // Don't warn about inline functions. 4065 if (FD->isInlineSpecified()) 4066 return false; 4067 4068 // Don't warn about function templates. 4069 if (FD->getDescribedFunctionTemplate()) 4070 return false; 4071 4072 // Don't warn about function template specializations. 4073 if (FD->isFunctionTemplateSpecialization()) 4074 return false; 4075 4076 bool MissingPrototype = true; 4077 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 4078 Prev; Prev = Prev->getPreviousDeclaration()) { 4079 // Ignore any declarations that occur in function or method 4080 // scope, because they aren't visible from the header. 4081 if (Prev->getDeclContext()->isFunctionOrMethod()) 4082 continue; 4083 4084 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 4085 break; 4086 } 4087 4088 return MissingPrototype; 4089} 4090 4091Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 4092 // Clear the last template instantiation error context. 4093 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 4094 4095 if (!D) 4096 return D; 4097 FunctionDecl *FD = 0; 4098 4099 if (FunctionTemplateDecl *FunTmpl 4100 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 4101 FD = FunTmpl->getTemplatedDecl(); 4102 else 4103 FD = cast<FunctionDecl>(D.getAs<Decl>()); 4104 4105 CurFunctionNeedsScopeChecking = false; 4106 4107 // See if this is a redefinition. 4108 const FunctionDecl *Definition; 4109 if (FD->getBody(Definition)) { 4110 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 4111 Diag(Definition->getLocation(), diag::note_previous_definition); 4112 } 4113 4114 // Builtin functions cannot be defined. 4115 if (unsigned BuiltinID = FD->getBuiltinID()) { 4116 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 4117 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 4118 FD->setInvalidDecl(); 4119 } 4120 } 4121 4122 // The return type of a function definition must be complete 4123 // (C99 6.9.1p3, C++ [dcl.fct]p6). 4124 QualType ResultType = FD->getResultType(); 4125 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 4126 !FD->isInvalidDecl() && 4127 RequireCompleteType(FD->getLocation(), ResultType, 4128 diag::err_func_def_incomplete_result)) 4129 FD->setInvalidDecl(); 4130 4131 // GNU warning -Wmissing-prototypes: 4132 // Warn if a global function is defined without a previous 4133 // prototype declaration. This warning is issued even if the 4134 // definition itself provides a prototype. The aim is to detect 4135 // global functions that fail to be declared in header files. 4136 if (ShouldWarnAboutMissingPrototype(FD)) 4137 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 4138 4139 if (FnBodyScope) 4140 PushDeclContext(FnBodyScope, FD); 4141 4142 // Check the validity of our function parameters 4143 CheckParmsForFunctionDef(FD); 4144 4145 // Introduce our parameters into the function scope 4146 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 4147 ParmVarDecl *Param = FD->getParamDecl(p); 4148 Param->setOwningFunction(FD); 4149 4150 // If this has an identifier, add it to the scope stack. 4151 if (Param->getIdentifier() && FnBodyScope) 4152 PushOnScopeChains(Param, FnBodyScope); 4153 } 4154 4155 // Checking attributes of current function definition 4156 // dllimport attribute. 4157 if (FD->getAttr<DLLImportAttr>() && 4158 (!FD->getAttr<DLLExportAttr>())) { 4159 // dllimport attribute cannot be applied to definition. 4160 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 4161 Diag(FD->getLocation(), 4162 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 4163 << "dllimport"; 4164 FD->setInvalidDecl(); 4165 return DeclPtrTy::make(FD); 4166 } else { 4167 // If a symbol previously declared dllimport is later defined, the 4168 // attribute is ignored in subsequent references, and a warning is 4169 // emitted. 4170 Diag(FD->getLocation(), 4171 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 4172 << FD->getNameAsCString() << "dllimport"; 4173 } 4174 } 4175 return DeclPtrTy::make(FD); 4176} 4177 4178Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 4179 return ActOnFinishFunctionBody(D, move(BodyArg), false); 4180} 4181 4182Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 4183 bool IsInstantiation) { 4184 Decl *dcl = D.getAs<Decl>(); 4185 Stmt *Body = BodyArg.takeAs<Stmt>(); 4186 4187 FunctionDecl *FD = 0; 4188 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 4189 if (FunTmpl) 4190 FD = FunTmpl->getTemplatedDecl(); 4191 else 4192 FD = dyn_cast_or_null<FunctionDecl>(dcl); 4193 4194 if (FD) { 4195 FD->setBody(Body); 4196 if (FD->isMain()) 4197 // C and C++ allow for main to automagically return 0. 4198 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 4199 FD->setHasImplicitReturnZero(true); 4200 else 4201 CheckFallThroughForFunctionDef(FD, Body); 4202 4203 if (!FD->isInvalidDecl()) 4204 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 4205 4206 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 4207 MaybeMarkVirtualMembersReferenced(Method->getLocation(), Method); 4208 4209 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 4210 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 4211 assert(MD == getCurMethodDecl() && "Method parsing confused"); 4212 MD->setBody(Body); 4213 CheckFallThroughForFunctionDef(MD, Body); 4214 MD->setEndLoc(Body->getLocEnd()); 4215 4216 if (!MD->isInvalidDecl()) 4217 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 4218 } else { 4219 Body->Destroy(Context); 4220 return DeclPtrTy(); 4221 } 4222 if (!IsInstantiation) 4223 PopDeclContext(); 4224 4225 // Verify and clean out per-function state. 4226 4227 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4228 4229 // Check goto/label use. 4230 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4231 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4232 LabelStmt *L = I->second; 4233 4234 // Verify that we have no forward references left. If so, there was a goto 4235 // or address of a label taken, but no definition of it. Label fwd 4236 // definitions are indicated with a null substmt. 4237 if (L->getSubStmt() != 0) 4238 continue; 4239 4240 // Emit error. 4241 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4242 4243 // At this point, we have gotos that use the bogus label. Stitch it into 4244 // the function body so that they aren't leaked and that the AST is well 4245 // formed. 4246 if (Body == 0) { 4247 // The whole function wasn't parsed correctly, just delete this. 4248 L->Destroy(Context); 4249 continue; 4250 } 4251 4252 // Otherwise, the body is valid: we want to stitch the label decl into the 4253 // function somewhere so that it is properly owned and so that the goto 4254 // has a valid target. Do this by creating a new compound stmt with the 4255 // label in it. 4256 4257 // Give the label a sub-statement. 4258 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4259 4260 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4261 cast<CXXTryStmt>(Body)->getTryBlock() : 4262 cast<CompoundStmt>(Body); 4263 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4264 Elements.push_back(L); 4265 Compound->setStmts(Context, &Elements[0], Elements.size()); 4266 } 4267 FunctionLabelMap.clear(); 4268 4269 if (!Body) return D; 4270 4271 // Verify that that gotos and switch cases don't jump into scopes illegally. 4272 if (CurFunctionNeedsScopeChecking) 4273 DiagnoseInvalidJumps(Body); 4274 4275 // C++ constructors that have function-try-blocks can't have return 4276 // statements in the handlers of that block. (C++ [except.handle]p14) 4277 // Verify this. 4278 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4279 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4280 4281 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4282 MarkBaseAndMemberDestructorsReferenced(Destructor); 4283 4284 // If any errors have occurred, clear out any temporaries that may have 4285 // been leftover. This ensures that these temporaries won't be picked up for 4286 // deletion in some later function. 4287 if (PP.getDiagnostics().hasErrorOccurred()) 4288 ExprTemporaries.clear(); 4289 4290 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4291 return D; 4292} 4293 4294/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4295/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4296NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4297 IdentifierInfo &II, Scope *S) { 4298 // Before we produce a declaration for an implicitly defined 4299 // function, see whether there was a locally-scoped declaration of 4300 // this name as a function or variable. If so, use that 4301 // (non-visible) declaration, and complain about it. 4302 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4303 = LocallyScopedExternalDecls.find(&II); 4304 if (Pos != LocallyScopedExternalDecls.end()) { 4305 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4306 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4307 return Pos->second; 4308 } 4309 4310 // Extension in C99. Legal in C90, but warn about it. 4311 if (II.getName().startswith("__builtin_")) 4312 Diag(Loc, diag::warn_builtin_unknown) << &II; 4313 else if (getLangOptions().C99) 4314 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4315 else 4316 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4317 4318 // Set a Declarator for the implicit definition: int foo(); 4319 const char *Dummy; 4320 DeclSpec DS; 4321 unsigned DiagID; 4322 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4323 Error = Error; // Silence warning. 4324 assert(!Error && "Error setting up implicit decl!"); 4325 Declarator D(DS, Declarator::BlockContext); 4326 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4327 0, 0, false, SourceLocation(), 4328 false, 0,0,0, Loc, Loc, D), 4329 SourceLocation()); 4330 D.SetIdentifier(&II, Loc); 4331 4332 // Insert this function into translation-unit scope. 4333 4334 DeclContext *PrevDC = CurContext; 4335 CurContext = Context.getTranslationUnitDecl(); 4336 4337 FunctionDecl *FD = 4338 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4339 FD->setImplicit(); 4340 4341 CurContext = PrevDC; 4342 4343 AddKnownFunctionAttributes(FD); 4344 4345 return FD; 4346} 4347 4348/// \brief Adds any function attributes that we know a priori based on 4349/// the declaration of this function. 4350/// 4351/// These attributes can apply both to implicitly-declared builtins 4352/// (like __builtin___printf_chk) or to library-declared functions 4353/// like NSLog or printf. 4354void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4355 if (FD->isInvalidDecl()) 4356 return; 4357 4358 // If this is a built-in function, map its builtin attributes to 4359 // actual attributes. 4360 if (unsigned BuiltinID = FD->getBuiltinID()) { 4361 // Handle printf-formatting attributes. 4362 unsigned FormatIdx; 4363 bool HasVAListArg; 4364 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4365 if (!FD->getAttr<FormatAttr>()) 4366 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4367 HasVAListArg ? 0 : FormatIdx + 2)); 4368 } 4369 4370 // Mark const if we don't care about errno and that is the only 4371 // thing preventing the function from being const. This allows 4372 // IRgen to use LLVM intrinsics for such functions. 4373 if (!getLangOptions().MathErrno && 4374 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4375 if (!FD->getAttr<ConstAttr>()) 4376 FD->addAttr(::new (Context) ConstAttr()); 4377 } 4378 4379 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4380 FD->addAttr(::new (Context) NoReturnAttr()); 4381 } 4382 4383 IdentifierInfo *Name = FD->getIdentifier(); 4384 if (!Name) 4385 return; 4386 if ((!getLangOptions().CPlusPlus && 4387 FD->getDeclContext()->isTranslationUnit()) || 4388 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4389 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4390 LinkageSpecDecl::lang_c)) { 4391 // Okay: this could be a libc/libm/Objective-C function we know 4392 // about. 4393 } else 4394 return; 4395 4396 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4397 // FIXME: NSLog and NSLogv should be target specific 4398 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4399 // FIXME: We known better than our headers. 4400 const_cast<FormatAttr *>(Format)->setType("printf"); 4401 } else 4402 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4403 Name->isStr("NSLogv") ? 0 : 2)); 4404 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4405 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4406 // target-specific builtins, perhaps? 4407 if (!FD->getAttr<FormatAttr>()) 4408 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4409 Name->isStr("vasprintf") ? 0 : 3)); 4410 } 4411} 4412 4413TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4414 TypeSourceInfo *TInfo) { 4415 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4416 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4417 4418 if (!TInfo) { 4419 assert(D.isInvalidType() && "no declarator info for valid type"); 4420 TInfo = Context.getTrivialTypeSourceInfo(T); 4421 } 4422 4423 // Scope manipulation handled by caller. 4424 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4425 D.getIdentifierLoc(), 4426 D.getIdentifier(), 4427 TInfo); 4428 4429 if (const TagType *TT = T->getAs<TagType>()) { 4430 TagDecl *TD = TT->getDecl(); 4431 4432 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4433 // keep track of the TypedefDecl. 4434 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4435 TD->setTypedefForAnonDecl(NewTD); 4436 } 4437 4438 if (D.isInvalidType()) 4439 NewTD->setInvalidDecl(); 4440 return NewTD; 4441} 4442 4443 4444/// \brief Determine whether a tag with a given kind is acceptable 4445/// as a redeclaration of the given tag declaration. 4446/// 4447/// \returns true if the new tag kind is acceptable, false otherwise. 4448bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4449 TagDecl::TagKind NewTag, 4450 SourceLocation NewTagLoc, 4451 const IdentifierInfo &Name) { 4452 // C++ [dcl.type.elab]p3: 4453 // The class-key or enum keyword present in the 4454 // elaborated-type-specifier shall agree in kind with the 4455 // declaration to which the name in theelaborated-type-specifier 4456 // refers. This rule also applies to the form of 4457 // elaborated-type-specifier that declares a class-name or 4458 // friend class since it can be construed as referring to the 4459 // definition of the class. Thus, in any 4460 // elaborated-type-specifier, the enum keyword shall be used to 4461 // refer to an enumeration (7.2), the union class-keyshall be 4462 // used to refer to a union (clause 9), and either the class or 4463 // struct class-key shall be used to refer to a class (clause 9) 4464 // declared using the class or struct class-key. 4465 TagDecl::TagKind OldTag = Previous->getTagKind(); 4466 if (OldTag == NewTag) 4467 return true; 4468 4469 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4470 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4471 // Warn about the struct/class tag mismatch. 4472 bool isTemplate = false; 4473 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4474 isTemplate = Record->getDescribedClassTemplate(); 4475 4476 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4477 << (NewTag == TagDecl::TK_class) 4478 << isTemplate << &Name 4479 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4480 OldTag == TagDecl::TK_class? "class" : "struct"); 4481 Diag(Previous->getLocation(), diag::note_previous_use); 4482 return true; 4483 } 4484 return false; 4485} 4486 4487/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4488/// former case, Name will be non-null. In the later case, Name will be null. 4489/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4490/// reference/declaration/definition of a tag. 4491Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4492 SourceLocation KWLoc, const CXXScopeSpec &SS, 4493 IdentifierInfo *Name, SourceLocation NameLoc, 4494 AttributeList *Attr, AccessSpecifier AS, 4495 MultiTemplateParamsArg TemplateParameterLists, 4496 bool &OwnedDecl, bool &IsDependent) { 4497 // If this is not a definition, it must have a name. 4498 assert((Name != 0 || TUK == TUK_Definition) && 4499 "Nameless record must be a definition!"); 4500 4501 OwnedDecl = false; 4502 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4503 4504 // FIXME: Check explicit specializations more carefully. 4505 bool isExplicitSpecialization = false; 4506 if (TUK != TUK_Reference) { 4507 if (TemplateParameterList *TemplateParams 4508 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4509 (TemplateParameterList**)TemplateParameterLists.get(), 4510 TemplateParameterLists.size(), 4511 isExplicitSpecialization)) { 4512 if (TemplateParams->size() > 0) { 4513 // This is a declaration or definition of a class template (which may 4514 // be a member of another template). 4515 OwnedDecl = false; 4516 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4517 SS, Name, NameLoc, Attr, 4518 TemplateParams, 4519 AS); 4520 TemplateParameterLists.release(); 4521 return Result.get(); 4522 } else { 4523 // The "template<>" header is extraneous. 4524 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4525 << ElaboratedType::getNameForTagKind(Kind) << Name; 4526 isExplicitSpecialization = true; 4527 } 4528 } 4529 4530 TemplateParameterLists.release(); 4531 } 4532 4533 DeclContext *SearchDC = CurContext; 4534 DeclContext *DC = CurContext; 4535 bool isStdBadAlloc = false; 4536 bool Invalid = false; 4537 4538 RedeclarationKind Redecl = (TUK != TUK_Reference ? ForRedeclaration 4539 : NotForRedeclaration); 4540 4541 LookupResult Previous(*this, Name, NameLoc, LookupTagName, Redecl); 4542 4543 if (Name && SS.isNotEmpty()) { 4544 // We have a nested-name tag ('struct foo::bar'). 4545 4546 // Check for invalid 'foo::'. 4547 if (SS.isInvalid()) { 4548 Name = 0; 4549 goto CreateNewDecl; 4550 } 4551 4552 // If this is a friend or a reference to a class in a dependent 4553 // context, don't try to make a decl for it. 4554 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4555 DC = computeDeclContext(SS, false); 4556 if (!DC) { 4557 IsDependent = true; 4558 return DeclPtrTy(); 4559 } 4560 } 4561 4562 if (RequireCompleteDeclContext(SS)) 4563 return DeclPtrTy::make((Decl *)0); 4564 4565 DC = computeDeclContext(SS, true); 4566 SearchDC = DC; 4567 // Look-up name inside 'foo::'. 4568 LookupQualifiedName(Previous, DC); 4569 4570 if (Previous.isAmbiguous()) 4571 return DeclPtrTy(); 4572 4573 // A tag 'foo::bar' must already exist. 4574 if (Previous.empty()) { 4575 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4576 Name = 0; 4577 Invalid = true; 4578 goto CreateNewDecl; 4579 } 4580 } else if (Name) { 4581 // If this is a named struct, check to see if there was a previous forward 4582 // declaration or definition. 4583 // FIXME: We're looking into outer scopes here, even when we 4584 // shouldn't be. Doing so can result in ambiguities that we 4585 // shouldn't be diagnosing. 4586 LookupName(Previous, S); 4587 4588 // Note: there used to be some attempt at recovery here. 4589 if (Previous.isAmbiguous()) 4590 return DeclPtrTy(); 4591 4592 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4593 // FIXME: This makes sure that we ignore the contexts associated 4594 // with C structs, unions, and enums when looking for a matching 4595 // tag declaration or definition. See the similar lookup tweak 4596 // in Sema::LookupName; is there a better way to deal with this? 4597 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4598 SearchDC = SearchDC->getParent(); 4599 } 4600 } 4601 4602 if (Previous.isSingleResult() && 4603 Previous.getFoundDecl()->isTemplateParameter()) { 4604 // Maybe we will complain about the shadowed template parameter. 4605 DiagnoseTemplateParameterShadow(NameLoc, Previous.getFoundDecl()); 4606 // Just pretend that we didn't see the previous declaration. 4607 Previous.clear(); 4608 } 4609 4610 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4611 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4612 // This is a declaration of or a reference to "std::bad_alloc". 4613 isStdBadAlloc = true; 4614 4615 if (Previous.empty() && StdBadAlloc) { 4616 // std::bad_alloc has been implicitly declared (but made invisible to 4617 // name lookup). Fill in this implicit declaration as the previous 4618 // declaration, so that the declarations get chained appropriately. 4619 Previous.addDecl(StdBadAlloc); 4620 } 4621 } 4622 4623 if (!Previous.empty()) { 4624 assert(Previous.isSingleResult()); 4625 NamedDecl *PrevDecl = Previous.getFoundDecl(); 4626 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4627 // If this is a use of a previous tag, or if the tag is already declared 4628 // in the same scope (so that the definition/declaration completes or 4629 // rementions the tag), reuse the decl. 4630 if (TUK == TUK_Reference || TUK == TUK_Friend || 4631 isDeclInScope(PrevDecl, SearchDC, S)) { 4632 // Make sure that this wasn't declared as an enum and now used as a 4633 // struct or something similar. 4634 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4635 bool SafeToContinue 4636 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4637 Kind != TagDecl::TK_enum); 4638 if (SafeToContinue) 4639 Diag(KWLoc, diag::err_use_with_wrong_tag) 4640 << Name 4641 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4642 PrevTagDecl->getKindName()); 4643 else 4644 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4645 Diag(PrevTagDecl->getLocation(), diag::note_previous_use); 4646 4647 if (SafeToContinue) 4648 Kind = PrevTagDecl->getTagKind(); 4649 else { 4650 // Recover by making this an anonymous redefinition. 4651 Name = 0; 4652 Previous.clear(); 4653 Invalid = true; 4654 } 4655 } 4656 4657 if (!Invalid) { 4658 // If this is a use, just return the declaration we found. 4659 4660 // FIXME: In the future, return a variant or some other clue 4661 // for the consumer of this Decl to know it doesn't own it. 4662 // For our current ASTs this shouldn't be a problem, but will 4663 // need to be changed with DeclGroups. 4664 if (TUK == TUK_Reference || TUK == TUK_Friend) 4665 return DeclPtrTy::make(PrevTagDecl); 4666 4667 // Diagnose attempts to redefine a tag. 4668 if (TUK == TUK_Definition) { 4669 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4670 // If we're defining a specialization and the previous definition 4671 // is from an implicit instantiation, don't emit an error 4672 // here; we'll catch this in the general case below. 4673 if (!isExplicitSpecialization || 4674 !isa<CXXRecordDecl>(Def) || 4675 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4676 == TSK_ExplicitSpecialization) { 4677 Diag(NameLoc, diag::err_redefinition) << Name; 4678 Diag(Def->getLocation(), diag::note_previous_definition); 4679 // If this is a redefinition, recover by making this 4680 // struct be anonymous, which will make any later 4681 // references get the previous definition. 4682 Name = 0; 4683 Previous.clear(); 4684 Invalid = true; 4685 } 4686 } else { 4687 // If the type is currently being defined, complain 4688 // about a nested redefinition. 4689 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4690 if (Tag->isBeingDefined()) { 4691 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4692 Diag(PrevTagDecl->getLocation(), 4693 diag::note_previous_definition); 4694 Name = 0; 4695 Previous.clear(); 4696 Invalid = true; 4697 } 4698 } 4699 4700 // Okay, this is definition of a previously declared or referenced 4701 // tag PrevDecl. We're going to create a new Decl for it. 4702 } 4703 } 4704 // If we get here we have (another) forward declaration or we 4705 // have a definition. Just create a new decl. 4706 4707 } else { 4708 // If we get here, this is a definition of a new tag type in a nested 4709 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4710 // new decl/type. We set PrevDecl to NULL so that the entities 4711 // have distinct types. 4712 Previous.clear(); 4713 } 4714 // If we get here, we're going to create a new Decl. If PrevDecl 4715 // is non-NULL, it's a definition of the tag declared by 4716 // PrevDecl. If it's NULL, we have a new definition. 4717 } else { 4718 // PrevDecl is a namespace, template, or anything else 4719 // that lives in the IDNS_Tag identifier namespace. 4720 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4721 // The tag name clashes with a namespace name, issue an error and 4722 // recover by making this tag be anonymous. 4723 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4724 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4725 Name = 0; 4726 Previous.clear(); 4727 Invalid = true; 4728 } else { 4729 // The existing declaration isn't relevant to us; we're in a 4730 // new scope, so clear out the previous declaration. 4731 Previous.clear(); 4732 } 4733 } 4734 } else if (TUK == TUK_Reference && SS.isEmpty() && Name) { 4735 // C++ [basic.scope.pdecl]p5: 4736 // -- for an elaborated-type-specifier of the form 4737 // 4738 // class-key identifier 4739 // 4740 // if the elaborated-type-specifier is used in the 4741 // decl-specifier-seq or parameter-declaration-clause of a 4742 // function defined in namespace scope, the identifier is 4743 // declared as a class-name in the namespace that contains 4744 // the declaration; otherwise, except as a friend 4745 // declaration, the identifier is declared in the smallest 4746 // non-class, non-function-prototype scope that contains the 4747 // declaration. 4748 // 4749 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4750 // C structs and unions. 4751 // 4752 // It is an error in C++ to declare (rather than define) an enum 4753 // type, including via an elaborated type specifier. We'll 4754 // diagnose that later; for now, declare the enum in the same 4755 // scope as we would have picked for any other tag type. 4756 // 4757 // GNU C also supports this behavior as part of its incomplete 4758 // enum types extension, while GNU C++ does not. 4759 // 4760 // Find the context where we'll be declaring the tag. 4761 // FIXME: We would like to maintain the current DeclContext as the 4762 // lexical context, 4763 while (SearchDC->isRecord()) 4764 SearchDC = SearchDC->getParent(); 4765 4766 // Find the scope where we'll be declaring the tag. 4767 while (S->isClassScope() || 4768 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4769 ((S->getFlags() & Scope::DeclScope) == 0) || 4770 (S->getEntity() && 4771 ((DeclContext *)S->getEntity())->isTransparentContext())) 4772 S = S->getParent(); 4773 4774 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4775 // C++ [namespace.memdef]p3: 4776 // If a friend declaration in a non-local class first declares a 4777 // class or function, the friend class or function is a member of 4778 // the innermost enclosing namespace. 4779 while (!SearchDC->isFileContext()) 4780 SearchDC = SearchDC->getParent(); 4781 4782 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4783 while (S->getEntity() != SearchDC) 4784 S = S->getParent(); 4785 } 4786 4787CreateNewDecl: 4788 4789 TagDecl *PrevDecl = 0; 4790 if (Previous.isSingleResult()) 4791 PrevDecl = cast<TagDecl>(Previous.getFoundDecl()); 4792 4793 // If there is an identifier, use the location of the identifier as the 4794 // location of the decl, otherwise use the location of the struct/union 4795 // keyword. 4796 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4797 4798 // Otherwise, create a new declaration. If there is a previous 4799 // declaration of the same entity, the two will be linked via 4800 // PrevDecl. 4801 TagDecl *New; 4802 4803 if (Kind == TagDecl::TK_enum) { 4804 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4805 // enum X { A, B, C } D; D should chain to X. 4806 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4807 cast_or_null<EnumDecl>(PrevDecl)); 4808 // If this is an undefined enum, warn. 4809 if (TUK != TUK_Definition && !Invalid) { 4810 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4811 : diag::ext_forward_ref_enum; 4812 Diag(Loc, DK); 4813 } 4814 } else { 4815 // struct/union/class 4816 4817 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4818 // struct X { int A; } D; D should chain to X. 4819 if (getLangOptions().CPlusPlus) { 4820 // FIXME: Look for a way to use RecordDecl for simple structs. 4821 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4822 cast_or_null<CXXRecordDecl>(PrevDecl)); 4823 4824 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4825 StdBadAlloc = cast<CXXRecordDecl>(New); 4826 } else 4827 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4828 cast_or_null<RecordDecl>(PrevDecl)); 4829 } 4830 4831 if (Kind != TagDecl::TK_enum) { 4832 // Handle #pragma pack: if the #pragma pack stack has non-default 4833 // alignment, make up a packed attribute for this decl. These 4834 // attributes are checked when the ASTContext lays out the 4835 // structure. 4836 // 4837 // It is important for implementing the correct semantics that this 4838 // happen here (in act on tag decl). The #pragma pack stack is 4839 // maintained as a result of parser callbacks which can occur at 4840 // many points during the parsing of a struct declaration (because 4841 // the #pragma tokens are effectively skipped over during the 4842 // parsing of the struct). 4843 if (unsigned Alignment = getPragmaPackAlignment()) 4844 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4845 } 4846 4847 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4848 // C++ [dcl.typedef]p3: 4849 // [...] Similarly, in a given scope, a class or enumeration 4850 // shall not be declared with the same name as a typedef-name 4851 // that is declared in that scope and refers to a type other 4852 // than the class or enumeration itself. 4853 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4854 ForRedeclaration); 4855 LookupName(Lookup, S); 4856 TypedefDecl *PrevTypedef = Lookup.getAsSingle<TypedefDecl>(); 4857 NamedDecl *PrevTypedefNamed = PrevTypedef; 4858 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4859 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4860 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4861 Diag(Loc, diag::err_tag_definition_of_typedef) 4862 << Context.getTypeDeclType(New) 4863 << PrevTypedef->getUnderlyingType(); 4864 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4865 Invalid = true; 4866 } 4867 } 4868 4869 // If this is a specialization of a member class (of a class template), 4870 // check the specialization. 4871 if (isExplicitSpecialization && CheckMemberSpecialization(New, Previous)) 4872 Invalid = true; 4873 4874 if (Invalid) 4875 New->setInvalidDecl(); 4876 4877 if (Attr) 4878 ProcessDeclAttributeList(S, New, Attr); 4879 4880 // If we're declaring or defining a tag in function prototype scope 4881 // in C, note that this type can only be used within the function. 4882 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4883 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4884 4885 // Set the lexical context. If the tag has a C++ scope specifier, the 4886 // lexical context will be different from the semantic context. 4887 New->setLexicalDeclContext(CurContext); 4888 4889 // Mark this as a friend decl if applicable. 4890 if (TUK == TUK_Friend) 4891 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ !Previous.empty()); 4892 4893 // Set the access specifier. 4894 if (!Invalid && TUK != TUK_Friend) 4895 SetMemberAccessSpecifier(New, PrevDecl, AS); 4896 4897 if (TUK == TUK_Definition) 4898 New->startDefinition(); 4899 4900 // If this has an identifier, add it to the scope stack. 4901 if (TUK == TUK_Friend) { 4902 // We might be replacing an existing declaration in the lookup tables; 4903 // if so, borrow its access specifier. 4904 if (PrevDecl) 4905 New->setAccess(PrevDecl->getAccess()); 4906 4907 // Friend tag decls are visible in fairly strange ways. 4908 if (!CurContext->isDependentContext()) { 4909 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4910 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4911 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4912 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4913 } 4914 } else if (Name) { 4915 S = getNonFieldDeclScope(S); 4916 PushOnScopeChains(New, S); 4917 } else { 4918 CurContext->addDecl(New); 4919 } 4920 4921 // If this is the C FILE type, notify the AST context. 4922 if (IdentifierInfo *II = New->getIdentifier()) 4923 if (!New->isInvalidDecl() && 4924 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4925 II->isStr("FILE")) 4926 Context.setFILEDecl(New); 4927 4928 OwnedDecl = true; 4929 return DeclPtrTy::make(New); 4930} 4931 4932void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4933 AdjustDeclIfTemplate(TagD); 4934 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4935 4936 // Enter the tag context. 4937 PushDeclContext(S, Tag); 4938 4939 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4940 FieldCollector->StartClass(); 4941 4942 if (Record->getIdentifier()) { 4943 // C++ [class]p2: 4944 // [...] The class-name is also inserted into the scope of the 4945 // class itself; this is known as the injected-class-name. For 4946 // purposes of access checking, the injected-class-name is treated 4947 // as if it were a public member name. 4948 CXXRecordDecl *InjectedClassName 4949 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4950 CurContext, Record->getLocation(), 4951 Record->getIdentifier(), 4952 Record->getTagKeywordLoc(), 4953 Record); 4954 InjectedClassName->setImplicit(); 4955 InjectedClassName->setAccess(AS_public); 4956 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4957 InjectedClassName->setDescribedClassTemplate(Template); 4958 PushOnScopeChains(InjectedClassName, S); 4959 assert(InjectedClassName->isInjectedClassName() && 4960 "Broken injected-class-name"); 4961 } 4962 } 4963} 4964 4965void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4966 SourceLocation RBraceLoc) { 4967 AdjustDeclIfTemplate(TagD); 4968 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4969 Tag->setRBraceLoc(RBraceLoc); 4970 4971 if (isa<CXXRecordDecl>(Tag)) 4972 FieldCollector->FinishClass(); 4973 4974 // Exit this scope of this tag's definition. 4975 PopDeclContext(); 4976 4977 // Notify the consumer that we've defined a tag. 4978 Consumer.HandleTagDeclDefinition(Tag); 4979} 4980 4981// Note that FieldName may be null for anonymous bitfields. 4982bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4983 QualType FieldTy, const Expr *BitWidth, 4984 bool *ZeroWidth) { 4985 // Default to true; that shouldn't confuse checks for emptiness 4986 if (ZeroWidth) 4987 *ZeroWidth = true; 4988 4989 // C99 6.7.2.1p4 - verify the field type. 4990 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4991 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4992 // Handle incomplete types with specific error. 4993 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4994 return true; 4995 if (FieldName) 4996 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4997 << FieldName << FieldTy << BitWidth->getSourceRange(); 4998 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4999 << FieldTy << BitWidth->getSourceRange(); 5000 } 5001 5002 // If the bit-width is type- or value-dependent, don't try to check 5003 // it now. 5004 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 5005 return false; 5006 5007 llvm::APSInt Value; 5008 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 5009 return true; 5010 5011 if (Value != 0 && ZeroWidth) 5012 *ZeroWidth = false; 5013 5014 // Zero-width bitfield is ok for anonymous field. 5015 if (Value == 0 && FieldName) 5016 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 5017 5018 if (Value.isSigned() && Value.isNegative()) { 5019 if (FieldName) 5020 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 5021 << FieldName << Value.toString(10); 5022 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 5023 << Value.toString(10); 5024 } 5025 5026 if (!FieldTy->isDependentType()) { 5027 uint64_t TypeSize = Context.getTypeSize(FieldTy); 5028 if (Value.getZExtValue() > TypeSize) { 5029 if (FieldName) 5030 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 5031 << FieldName << (unsigned)TypeSize; 5032 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 5033 << (unsigned)TypeSize; 5034 } 5035 } 5036 5037 return false; 5038} 5039 5040/// ActOnField - Each field of a struct/union/class is passed into this in order 5041/// to create a FieldDecl object for it. 5042Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 5043 SourceLocation DeclStart, 5044 Declarator &D, ExprTy *BitfieldWidth) { 5045 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 5046 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 5047 AS_public); 5048 return DeclPtrTy::make(Res); 5049} 5050 5051/// HandleField - Analyze a field of a C struct or a C++ data member. 5052/// 5053FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 5054 SourceLocation DeclStart, 5055 Declarator &D, Expr *BitWidth, 5056 AccessSpecifier AS) { 5057 IdentifierInfo *II = D.getIdentifier(); 5058 SourceLocation Loc = DeclStart; 5059 if (II) Loc = D.getIdentifierLoc(); 5060 5061 TypeSourceInfo *TInfo = 0; 5062 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5063 if (getLangOptions().CPlusPlus) 5064 CheckExtraCXXDefaultArguments(D); 5065 5066 DiagnoseFunctionSpecifiers(D); 5067 5068 if (D.getDeclSpec().isThreadSpecified()) 5069 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 5070 5071 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5072 ForRedeclaration); 5073 5074 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5075 // Maybe we will complain about the shadowed template parameter. 5076 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 5077 // Just pretend that we didn't see the previous declaration. 5078 PrevDecl = 0; 5079 } 5080 5081 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 5082 PrevDecl = 0; 5083 5084 bool Mutable 5085 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 5086 SourceLocation TSSL = D.getSourceRange().getBegin(); 5087 FieldDecl *NewFD 5088 = CheckFieldDecl(II, T, TInfo, Record, Loc, Mutable, BitWidth, TSSL, 5089 AS, PrevDecl, &D); 5090 if (NewFD->isInvalidDecl() && PrevDecl) { 5091 // Don't introduce NewFD into scope; there's already something 5092 // with the same name in the same scope. 5093 } else if (II) { 5094 PushOnScopeChains(NewFD, S); 5095 } else 5096 Record->addDecl(NewFD); 5097 5098 return NewFD; 5099} 5100 5101/// \brief Build a new FieldDecl and check its well-formedness. 5102/// 5103/// This routine builds a new FieldDecl given the fields name, type, 5104/// record, etc. \p PrevDecl should refer to any previous declaration 5105/// with the same name and in the same scope as the field to be 5106/// created. 5107/// 5108/// \returns a new FieldDecl. 5109/// 5110/// \todo The Declarator argument is a hack. It will be removed once 5111FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 5112 TypeSourceInfo *TInfo, 5113 RecordDecl *Record, SourceLocation Loc, 5114 bool Mutable, Expr *BitWidth, 5115 SourceLocation TSSL, 5116 AccessSpecifier AS, NamedDecl *PrevDecl, 5117 Declarator *D) { 5118 IdentifierInfo *II = Name.getAsIdentifierInfo(); 5119 bool InvalidDecl = false; 5120 if (D) InvalidDecl = D->isInvalidType(); 5121 5122 // If we receive a broken type, recover by assuming 'int' and 5123 // marking this declaration as invalid. 5124 if (T.isNull()) { 5125 InvalidDecl = true; 5126 T = Context.IntTy; 5127 } 5128 5129 QualType EltTy = Context.getBaseElementType(T); 5130 if (!EltTy->isDependentType() && 5131 RequireCompleteType(Loc, EltTy, diag::err_field_incomplete)) 5132 InvalidDecl = true; 5133 5134 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5135 // than a variably modified type. 5136 if (!InvalidDecl && T->isVariablyModifiedType()) { 5137 bool SizeIsNegative; 5138 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 5139 SizeIsNegative); 5140 if (!FixedTy.isNull()) { 5141 Diag(Loc, diag::warn_illegal_constant_array_size); 5142 T = FixedTy; 5143 } else { 5144 if (SizeIsNegative) 5145 Diag(Loc, diag::err_typecheck_negative_array_size); 5146 else 5147 Diag(Loc, diag::err_typecheck_field_variable_size); 5148 InvalidDecl = true; 5149 } 5150 } 5151 5152 // Fields can not have abstract class types 5153 if (!InvalidDecl && RequireNonAbstractType(Loc, T, 5154 diag::err_abstract_type_in_decl, 5155 AbstractFieldType)) 5156 InvalidDecl = true; 5157 5158 bool ZeroWidth = false; 5159 // If this is declared as a bit-field, check the bit-field. 5160 if (!InvalidDecl && BitWidth && 5161 VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 5162 InvalidDecl = true; 5163 DeleteExpr(BitWidth); 5164 BitWidth = 0; 5165 ZeroWidth = false; 5166 } 5167 5168 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, TInfo, 5169 BitWidth, Mutable); 5170 if (InvalidDecl) 5171 NewFD->setInvalidDecl(); 5172 5173 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 5174 Diag(Loc, diag::err_duplicate_member) << II; 5175 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5176 NewFD->setInvalidDecl(); 5177 } 5178 5179 if (getLangOptions().CPlusPlus) { 5180 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 5181 5182 if (!T->isPODType()) 5183 CXXRecord->setPOD(false); 5184 if (!ZeroWidth) 5185 CXXRecord->setEmpty(false); 5186 5187 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 5188 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 5189 5190 if (!RDecl->hasTrivialConstructor()) 5191 CXXRecord->setHasTrivialConstructor(false); 5192 if (!RDecl->hasTrivialCopyConstructor()) 5193 CXXRecord->setHasTrivialCopyConstructor(false); 5194 if (!RDecl->hasTrivialCopyAssignment()) 5195 CXXRecord->setHasTrivialCopyAssignment(false); 5196 if (!RDecl->hasTrivialDestructor()) 5197 CXXRecord->setHasTrivialDestructor(false); 5198 5199 // C++ 9.5p1: An object of a class with a non-trivial 5200 // constructor, a non-trivial copy constructor, a non-trivial 5201 // destructor, or a non-trivial copy assignment operator 5202 // cannot be a member of a union, nor can an array of such 5203 // objects. 5204 // TODO: C++0x alters this restriction significantly. 5205 if (Record->isUnion()) { 5206 // We check for copy constructors before constructors 5207 // because otherwise we'll never get complaints about 5208 // copy constructors. 5209 5210 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 5211 5212 CXXSpecialMember member; 5213 if (!RDecl->hasTrivialCopyConstructor()) 5214 member = CXXCopyConstructor; 5215 else if (!RDecl->hasTrivialConstructor()) 5216 member = CXXDefaultConstructor; 5217 else if (!RDecl->hasTrivialCopyAssignment()) 5218 member = CXXCopyAssignment; 5219 else if (!RDecl->hasTrivialDestructor()) 5220 member = CXXDestructor; 5221 else 5222 member = invalid; 5223 5224 if (member != invalid) { 5225 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5226 DiagnoseNontrivial(RT, member); 5227 NewFD->setInvalidDecl(); 5228 } 5229 } 5230 } 5231 } 5232 5233 // FIXME: We need to pass in the attributes given an AST 5234 // representation, not a parser representation. 5235 if (D) 5236 // FIXME: What to pass instead of TUScope? 5237 ProcessDeclAttributes(TUScope, NewFD, *D); 5238 5239 if (T.isObjCGCWeak()) 5240 Diag(Loc, diag::warn_attribute_weak_on_field); 5241 5242 NewFD->setAccess(AS); 5243 5244 // C++ [dcl.init.aggr]p1: 5245 // An aggregate is an array or a class (clause 9) with [...] no 5246 // private or protected non-static data members (clause 11). 5247 // A POD must be an aggregate. 5248 if (getLangOptions().CPlusPlus && 5249 (AS == AS_private || AS == AS_protected)) { 5250 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5251 CXXRecord->setAggregate(false); 5252 CXXRecord->setPOD(false); 5253 } 5254 5255 return NewFD; 5256} 5257 5258/// DiagnoseNontrivial - Given that a class has a non-trivial 5259/// special member, figure out why. 5260void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5261 QualType QT(T, 0U); 5262 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5263 5264 // Check whether the member was user-declared. 5265 switch (member) { 5266 case CXXDefaultConstructor: 5267 if (RD->hasUserDeclaredConstructor()) { 5268 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5269 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5270 const FunctionDecl *body = 0; 5271 ci->getBody(body); 5272 if (!body || 5273 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5274 SourceLocation CtorLoc = ci->getLocation(); 5275 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5276 return; 5277 } 5278 } 5279 5280 assert(0 && "found no user-declared constructors"); 5281 return; 5282 } 5283 break; 5284 5285 case CXXCopyConstructor: 5286 if (RD->hasUserDeclaredCopyConstructor()) { 5287 SourceLocation CtorLoc = 5288 RD->getCopyConstructor(Context, 0)->getLocation(); 5289 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5290 return; 5291 } 5292 break; 5293 5294 case CXXCopyAssignment: 5295 if (RD->hasUserDeclaredCopyAssignment()) { 5296 // FIXME: this should use the location of the copy 5297 // assignment, not the type. 5298 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5299 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5300 return; 5301 } 5302 break; 5303 5304 case CXXDestructor: 5305 if (RD->hasUserDeclaredDestructor()) { 5306 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5307 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5308 return; 5309 } 5310 break; 5311 } 5312 5313 typedef CXXRecordDecl::base_class_iterator base_iter; 5314 5315 // Virtual bases and members inhibit trivial copying/construction, 5316 // but not trivial destruction. 5317 if (member != CXXDestructor) { 5318 // Check for virtual bases. vbases includes indirect virtual bases, 5319 // so we just iterate through the direct bases. 5320 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5321 if (bi->isVirtual()) { 5322 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5323 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5324 return; 5325 } 5326 5327 // Check for virtual methods. 5328 typedef CXXRecordDecl::method_iterator meth_iter; 5329 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5330 ++mi) { 5331 if (mi->isVirtual()) { 5332 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5333 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5334 return; 5335 } 5336 } 5337 } 5338 5339 bool (CXXRecordDecl::*hasTrivial)() const; 5340 switch (member) { 5341 case CXXDefaultConstructor: 5342 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5343 case CXXCopyConstructor: 5344 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5345 case CXXCopyAssignment: 5346 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5347 case CXXDestructor: 5348 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5349 default: 5350 assert(0 && "unexpected special member"); return; 5351 } 5352 5353 // Check for nontrivial bases (and recurse). 5354 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5355 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5356 assert(BaseRT && "Don't know how to handle dependent bases"); 5357 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5358 if (!(BaseRecTy->*hasTrivial)()) { 5359 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5360 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5361 DiagnoseNontrivial(BaseRT, member); 5362 return; 5363 } 5364 } 5365 5366 // Check for nontrivial members (and recurse). 5367 typedef RecordDecl::field_iterator field_iter; 5368 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5369 ++fi) { 5370 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5371 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5372 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5373 5374 if (!(EltRD->*hasTrivial)()) { 5375 SourceLocation FLoc = (*fi)->getLocation(); 5376 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5377 DiagnoseNontrivial(EltRT, member); 5378 return; 5379 } 5380 } 5381 } 5382 5383 assert(0 && "found no explanation for non-trivial member"); 5384} 5385 5386/// TranslateIvarVisibility - Translate visibility from a token ID to an 5387/// AST enum value. 5388static ObjCIvarDecl::AccessControl 5389TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5390 switch (ivarVisibility) { 5391 default: assert(0 && "Unknown visitibility kind"); 5392 case tok::objc_private: return ObjCIvarDecl::Private; 5393 case tok::objc_public: return ObjCIvarDecl::Public; 5394 case tok::objc_protected: return ObjCIvarDecl::Protected; 5395 case tok::objc_package: return ObjCIvarDecl::Package; 5396 } 5397} 5398 5399/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5400/// in order to create an IvarDecl object for it. 5401Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5402 SourceLocation DeclStart, 5403 DeclPtrTy IntfDecl, 5404 Declarator &D, ExprTy *BitfieldWidth, 5405 tok::ObjCKeywordKind Visibility) { 5406 5407 IdentifierInfo *II = D.getIdentifier(); 5408 Expr *BitWidth = (Expr*)BitfieldWidth; 5409 SourceLocation Loc = DeclStart; 5410 if (II) Loc = D.getIdentifierLoc(); 5411 5412 // FIXME: Unnamed fields can be handled in various different ways, for 5413 // example, unnamed unions inject all members into the struct namespace! 5414 5415 TypeSourceInfo *TInfo = 0; 5416 QualType T = GetTypeForDeclarator(D, S, &TInfo); 5417 5418 if (BitWidth) { 5419 // 6.7.2.1p3, 6.7.2.1p4 5420 if (VerifyBitField(Loc, II, T, BitWidth)) { 5421 D.setInvalidType(); 5422 DeleteExpr(BitWidth); 5423 BitWidth = 0; 5424 } 5425 } else { 5426 // Not a bitfield. 5427 5428 // validate II. 5429 5430 } 5431 5432 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5433 // than a variably modified type. 5434 if (T->isVariablyModifiedType()) { 5435 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5436 D.setInvalidType(); 5437 } 5438 5439 // Get the visibility (access control) for this ivar. 5440 ObjCIvarDecl::AccessControl ac = 5441 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5442 : ObjCIvarDecl::None; 5443 // Must set ivar's DeclContext to its enclosing interface. 5444 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5445 DeclContext *EnclosingContext; 5446 if (ObjCImplementationDecl *IMPDecl = 5447 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5448 // Case of ivar declared in an implementation. Context is that of its class. 5449 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5450 assert(IDecl && "No class- ActOnIvar"); 5451 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5452 } else 5453 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5454 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5455 5456 // Construct the decl. 5457 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5458 EnclosingContext, Loc, II, T, 5459 TInfo, ac, (Expr *)BitfieldWidth); 5460 5461 if (II) { 5462 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5463 ForRedeclaration); 5464 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5465 && !isa<TagDecl>(PrevDecl)) { 5466 Diag(Loc, diag::err_duplicate_member) << II; 5467 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5468 NewID->setInvalidDecl(); 5469 } 5470 } 5471 5472 // Process attributes attached to the ivar. 5473 ProcessDeclAttributes(S, NewID, D); 5474 5475 if (D.isInvalidType()) 5476 NewID->setInvalidDecl(); 5477 5478 if (II) { 5479 // FIXME: When interfaces are DeclContexts, we'll need to add 5480 // these to the interface. 5481 S->AddDecl(DeclPtrTy::make(NewID)); 5482 IdResolver.AddDecl(NewID); 5483 } 5484 5485 return DeclPtrTy::make(NewID); 5486} 5487 5488void Sema::ActOnFields(Scope* S, 5489 SourceLocation RecLoc, DeclPtrTy RecDecl, 5490 DeclPtrTy *Fields, unsigned NumFields, 5491 SourceLocation LBrac, SourceLocation RBrac, 5492 AttributeList *Attr) { 5493 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5494 assert(EnclosingDecl && "missing record or interface decl"); 5495 5496 // If the decl this is being inserted into is invalid, then it may be a 5497 // redeclaration or some other bogus case. Don't try to add fields to it. 5498 if (EnclosingDecl->isInvalidDecl()) { 5499 // FIXME: Deallocate fields? 5500 return; 5501 } 5502 5503 5504 // Verify that all the fields are okay. 5505 unsigned NumNamedMembers = 0; 5506 llvm::SmallVector<FieldDecl*, 32> RecFields; 5507 5508 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5509 for (unsigned i = 0; i != NumFields; ++i) { 5510 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5511 5512 // Get the type for the field. 5513 Type *FDTy = FD->getType().getTypePtr(); 5514 5515 if (!FD->isAnonymousStructOrUnion()) { 5516 // Remember all fields written by the user. 5517 RecFields.push_back(FD); 5518 } 5519 5520 // If the field is already invalid for some reason, don't emit more 5521 // diagnostics about it. 5522 if (FD->isInvalidDecl()) { 5523 EnclosingDecl->setInvalidDecl(); 5524 continue; 5525 } 5526 5527 // C99 6.7.2.1p2: 5528 // A structure or union shall not contain a member with 5529 // incomplete or function type (hence, a structure shall not 5530 // contain an instance of itself, but may contain a pointer to 5531 // an instance of itself), except that the last member of a 5532 // structure with more than one named member may have incomplete 5533 // array type; such a structure (and any union containing, 5534 // possibly recursively, a member that is such a structure) 5535 // shall not be a member of a structure or an element of an 5536 // array. 5537 if (FDTy->isFunctionType()) { 5538 // Field declared as a function. 5539 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5540 << FD->getDeclName(); 5541 FD->setInvalidDecl(); 5542 EnclosingDecl->setInvalidDecl(); 5543 continue; 5544 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5545 Record && Record->isStruct()) { 5546 // Flexible array member. 5547 if (NumNamedMembers < 1) { 5548 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5549 << FD->getDeclName(); 5550 FD->setInvalidDecl(); 5551 EnclosingDecl->setInvalidDecl(); 5552 continue; 5553 } 5554 // Okay, we have a legal flexible array member at the end of the struct. 5555 if (Record) 5556 Record->setHasFlexibleArrayMember(true); 5557 } else if (!FDTy->isDependentType() && 5558 RequireCompleteType(FD->getLocation(), FD->getType(), 5559 diag::err_field_incomplete)) { 5560 // Incomplete type 5561 FD->setInvalidDecl(); 5562 EnclosingDecl->setInvalidDecl(); 5563 continue; 5564 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5565 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5566 // If this is a member of a union, then entire union becomes "flexible". 5567 if (Record && Record->isUnion()) { 5568 Record->setHasFlexibleArrayMember(true); 5569 } else { 5570 // If this is a struct/class and this is not the last element, reject 5571 // it. Note that GCC supports variable sized arrays in the middle of 5572 // structures. 5573 if (i != NumFields-1) 5574 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5575 << FD->getDeclName() << FD->getType(); 5576 else { 5577 // We support flexible arrays at the end of structs in 5578 // other structs as an extension. 5579 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5580 << FD->getDeclName(); 5581 if (Record) 5582 Record->setHasFlexibleArrayMember(true); 5583 } 5584 } 5585 } 5586 if (Record && FDTTy->getDecl()->hasObjectMember()) 5587 Record->setHasObjectMember(true); 5588 } else if (FDTy->isObjCInterfaceType()) { 5589 /// A field cannot be an Objective-c object 5590 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5591 FD->setInvalidDecl(); 5592 EnclosingDecl->setInvalidDecl(); 5593 continue; 5594 } else if (getLangOptions().ObjC1 && 5595 getLangOptions().getGCMode() != LangOptions::NonGC && 5596 Record && 5597 (FD->getType()->isObjCObjectPointerType() || 5598 FD->getType().isObjCGCStrong())) 5599 Record->setHasObjectMember(true); 5600 // Keep track of the number of named members. 5601 if (FD->getIdentifier()) 5602 ++NumNamedMembers; 5603 } 5604 5605 // Okay, we successfully defined 'Record'. 5606 if (Record) { 5607 Record->completeDefinition(Context); 5608 } else { 5609 ObjCIvarDecl **ClsFields = 5610 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5611 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5612 ID->setIVarList(ClsFields, RecFields.size(), Context); 5613 ID->setLocEnd(RBrac); 5614 // Add ivar's to class's DeclContext. 5615 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5616 ClsFields[i]->setLexicalDeclContext(ID); 5617 ID->addDecl(ClsFields[i]); 5618 } 5619 // Must enforce the rule that ivars in the base classes may not be 5620 // duplicates. 5621 if (ID->getSuperClass()) { 5622 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5623 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5624 ObjCIvarDecl* Ivar = (*IVI); 5625 5626 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5627 ObjCIvarDecl* prevIvar = 5628 ID->getSuperClass()->lookupInstanceVariable(II); 5629 if (prevIvar) { 5630 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5631 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5632 } 5633 } 5634 } 5635 } 5636 } else if (ObjCImplementationDecl *IMPDecl = 5637 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5638 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5639 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5640 // Ivar declared in @implementation never belongs to the implementation. 5641 // Only it is in implementation's lexical context. 5642 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5643 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5644 } 5645 } 5646 5647 if (Attr) 5648 ProcessDeclAttributeList(S, Record, Attr); 5649} 5650 5651EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5652 EnumConstantDecl *LastEnumConst, 5653 SourceLocation IdLoc, 5654 IdentifierInfo *Id, 5655 ExprArg val) { 5656 Expr *Val = (Expr *)val.get(); 5657 5658 llvm::APSInt EnumVal(32); 5659 QualType EltTy; 5660 if (Val) { 5661 if (Val->isTypeDependent()) 5662 EltTy = Context.DependentTy; 5663 else { 5664 // Make sure to promote the operand type to int. 5665 UsualUnaryConversions(Val); 5666 if (Val != val.get()) { 5667 val.release(); 5668 val = Val; 5669 } 5670 5671 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5672 SourceLocation ExpLoc; 5673 if (!Val->isValueDependent() && 5674 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5675 Val = 0; 5676 } else { 5677 EltTy = Val->getType(); 5678 } 5679 } 5680 } 5681 5682 if (!Val) { 5683 if (LastEnumConst) { 5684 // Assign the last value + 1. 5685 EnumVal = LastEnumConst->getInitVal(); 5686 ++EnumVal; 5687 5688 // Check for overflow on increment. 5689 if (EnumVal < LastEnumConst->getInitVal()) 5690 Diag(IdLoc, diag::warn_enum_value_overflow); 5691 5692 EltTy = LastEnumConst->getType(); 5693 } else { 5694 // First value, set to zero. 5695 EltTy = Context.IntTy; 5696 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5697 EnumVal.setIsSigned(true); 5698 } 5699 } 5700 5701 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5702 5703 val.release(); 5704 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5705 Val, EnumVal); 5706} 5707 5708 5709Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5710 DeclPtrTy lastEnumConst, 5711 SourceLocation IdLoc, 5712 IdentifierInfo *Id, 5713 SourceLocation EqualLoc, ExprTy *val) { 5714 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5715 EnumConstantDecl *LastEnumConst = 5716 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5717 Expr *Val = static_cast<Expr*>(val); 5718 5719 // The scope passed in may not be a decl scope. Zip up the scope tree until 5720 // we find one that is. 5721 S = getNonFieldDeclScope(S); 5722 5723 // Verify that there isn't already something declared with this name in this 5724 // scope. 5725 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5726 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5727 // Maybe we will complain about the shadowed template parameter. 5728 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5729 // Just pretend that we didn't see the previous declaration. 5730 PrevDecl = 0; 5731 } 5732 5733 if (PrevDecl) { 5734 // When in C++, we may get a TagDecl with the same name; in this case the 5735 // enum constant will 'hide' the tag. 5736 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5737 "Received TagDecl when not in C++!"); 5738 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5739 if (isa<EnumConstantDecl>(PrevDecl)) 5740 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5741 else 5742 Diag(IdLoc, diag::err_redefinition) << Id; 5743 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5744 if (Val) Val->Destroy(Context); 5745 return DeclPtrTy(); 5746 } 5747 } 5748 5749 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5750 IdLoc, Id, Owned(Val)); 5751 5752 // Register this decl in the current scope stack. 5753 if (New) 5754 PushOnScopeChains(New, S); 5755 5756 return DeclPtrTy::make(New); 5757} 5758 5759void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5760 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5761 DeclPtrTy *Elements, unsigned NumElements, 5762 Scope *S, AttributeList *Attr) { 5763 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5764 QualType EnumType = Context.getTypeDeclType(Enum); 5765 5766 if (Attr) 5767 ProcessDeclAttributeList(S, Enum, Attr); 5768 5769 // TODO: If the result value doesn't fit in an int, it must be a long or long 5770 // long value. ISO C does not support this, but GCC does as an extension, 5771 // emit a warning. 5772 unsigned IntWidth = Context.Target.getIntWidth(); 5773 unsigned CharWidth = Context.Target.getCharWidth(); 5774 unsigned ShortWidth = Context.Target.getShortWidth(); 5775 5776 // Verify that all the values are okay, compute the size of the values, and 5777 // reverse the list. 5778 unsigned NumNegativeBits = 0; 5779 unsigned NumPositiveBits = 0; 5780 5781 // Keep track of whether all elements have type int. 5782 bool AllElementsInt = true; 5783 5784 for (unsigned i = 0; i != NumElements; ++i) { 5785 EnumConstantDecl *ECD = 5786 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5787 if (!ECD) continue; // Already issued a diagnostic. 5788 5789 // If the enum value doesn't fit in an int, emit an extension warning. 5790 const llvm::APSInt &InitVal = ECD->getInitVal(); 5791 assert(InitVal.getBitWidth() >= IntWidth && 5792 "Should have promoted value to int"); 5793 if (InitVal.getBitWidth() > IntWidth) { 5794 llvm::APSInt V(InitVal); 5795 V.trunc(IntWidth); 5796 V.extend(InitVal.getBitWidth()); 5797 if (V != InitVal) 5798 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5799 << InitVal.toString(10); 5800 } 5801 5802 // Keep track of the size of positive and negative values. 5803 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5804 NumPositiveBits = std::max(NumPositiveBits, 5805 (unsigned)InitVal.getActiveBits()); 5806 else 5807 NumNegativeBits = std::max(NumNegativeBits, 5808 (unsigned)InitVal.getMinSignedBits()); 5809 5810 // Keep track of whether every enum element has type int (very commmon). 5811 if (AllElementsInt) 5812 AllElementsInt = ECD->getType() == Context.IntTy; 5813 } 5814 5815 // Figure out the type that should be used for this enum. 5816 // FIXME: Support -fshort-enums. 5817 QualType BestType; 5818 unsigned BestWidth; 5819 5820 // C++0x N3000 [conv.prom]p3: 5821 // An rvalue of an unscoped enumeration type whose underlying 5822 // type is not fixed can be converted to an rvalue of the first 5823 // of the following types that can represent all the values of 5824 // the enumeration: int, unsigned int, long int, unsigned long 5825 // int, long long int, or unsigned long long int. 5826 // C99 6.4.4.3p2: 5827 // An identifier declared as an enumeration constant has type int. 5828 // The C99 rule is modified by a gcc extension 5829 QualType BestPromotionType; 5830 5831 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5832 5833 if (NumNegativeBits) { 5834 // If there is a negative value, figure out the smallest integer type (of 5835 // int/long/longlong) that fits. 5836 // If it's packed, check also if it fits a char or a short. 5837 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5838 BestType = Context.SignedCharTy; 5839 BestWidth = CharWidth; 5840 } else if (Packed && NumNegativeBits <= ShortWidth && 5841 NumPositiveBits < ShortWidth) { 5842 BestType = Context.ShortTy; 5843 BestWidth = ShortWidth; 5844 } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5845 BestType = Context.IntTy; 5846 BestWidth = IntWidth; 5847 } else { 5848 BestWidth = Context.Target.getLongWidth(); 5849 5850 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) { 5851 BestType = Context.LongTy; 5852 } else { 5853 BestWidth = Context.Target.getLongLongWidth(); 5854 5855 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5856 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5857 BestType = Context.LongLongTy; 5858 } 5859 } 5860 BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : BestType); 5861 } else { 5862 // If there is no negative value, figure out which of uint, ulong, ulonglong 5863 // fits. 5864 // If it's packed, check also if it fits a char or a short. 5865 if (Packed && NumPositiveBits <= CharWidth) { 5866 BestType = Context.UnsignedCharTy; 5867 BestPromotionType = Context.IntTy; 5868 BestWidth = CharWidth; 5869 } else if (Packed && NumPositiveBits <= ShortWidth) { 5870 BestType = Context.UnsignedShortTy; 5871 BestPromotionType = Context.IntTy; 5872 BestWidth = ShortWidth; 5873 } else if (NumPositiveBits <= IntWidth) { 5874 BestType = Context.UnsignedIntTy; 5875 BestWidth = IntWidth; 5876 BestPromotionType = (NumPositiveBits == BestWidth 5877 ? Context.UnsignedIntTy : Context.IntTy); 5878 } else if (NumPositiveBits <= 5879 (BestWidth = Context.Target.getLongWidth())) { 5880 BestType = Context.UnsignedLongTy; 5881 BestPromotionType = (NumPositiveBits == BestWidth 5882 ? Context.UnsignedLongTy : Context.LongTy); 5883 } else { 5884 BestWidth = Context.Target.getLongLongWidth(); 5885 assert(NumPositiveBits <= BestWidth && 5886 "How could an initializer get larger than ULL?"); 5887 BestType = Context.UnsignedLongLongTy; 5888 BestPromotionType = (NumPositiveBits == BestWidth 5889 ? Context.UnsignedLongLongTy : Context.LongLongTy); 5890 } 5891 } 5892 5893 // If we're in C and the promotion type is larger than an int, just 5894 // use the underlying type, which is generally the unsigned integer 5895 // type of the same rank as the promotion type. This is how the gcc 5896 // extension works. 5897 if (!getLangOptions().CPlusPlus && BestPromotionType != Context.IntTy) 5898 BestPromotionType = BestType; 5899 5900 // Loop over all of the enumerator constants, changing their types to match 5901 // the type of the enum if needed. 5902 for (unsigned i = 0; i != NumElements; ++i) { 5903 EnumConstantDecl *ECD = 5904 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5905 if (!ECD) continue; // Already issued a diagnostic. 5906 5907 // Standard C says the enumerators have int type, but we allow, as an 5908 // extension, the enumerators to be larger than int size. If each 5909 // enumerator value fits in an int, type it as an int, otherwise type it the 5910 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5911 // that X has type 'int', not 'unsigned'. 5912 if (!getLangOptions().CPlusPlus && ECD->getType() == Context.IntTy) 5913 continue; 5914 5915 // Determine whether the value fits into an int. 5916 llvm::APSInt InitVal = ECD->getInitVal(); 5917 bool FitsInInt; 5918 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5919 FitsInInt = InitVal.getActiveBits() < IntWidth; 5920 else 5921 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5922 5923 // If it fits into an integer type, force it. Otherwise force it to match 5924 // the enum decl type. 5925 QualType NewTy; 5926 unsigned NewWidth; 5927 bool NewSign; 5928 if (FitsInInt && !getLangOptions().CPlusPlus) { 5929 NewTy = Context.IntTy; 5930 NewWidth = IntWidth; 5931 NewSign = true; 5932 } else if (ECD->getType() == BestType) { 5933 // Already the right type! 5934 if (getLangOptions().CPlusPlus) 5935 // C++ [dcl.enum]p4: Following the closing brace of an 5936 // enum-specifier, each enumerator has the type of its 5937 // enumeration. 5938 ECD->setType(EnumType); 5939 continue; 5940 } else { 5941 NewTy = BestType; 5942 NewWidth = BestWidth; 5943 NewSign = BestType->isSignedIntegerType(); 5944 } 5945 5946 // Adjust the APSInt value. 5947 InitVal.extOrTrunc(NewWidth); 5948 InitVal.setIsSigned(NewSign); 5949 ECD->setInitVal(InitVal); 5950 5951 // Adjust the Expr initializer and type. 5952 if (ECD->getInitExpr()) 5953 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5954 CastExpr::CK_IntegralCast, 5955 ECD->getInitExpr(), 5956 /*isLvalue=*/false)); 5957 if (getLangOptions().CPlusPlus) 5958 // C++ [dcl.enum]p4: Following the closing brace of an 5959 // enum-specifier, each enumerator has the type of its 5960 // enumeration. 5961 ECD->setType(EnumType); 5962 else 5963 ECD->setType(NewTy); 5964 } 5965 5966 Enum->completeDefinition(Context, BestType, BestPromotionType); 5967} 5968 5969Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5970 ExprArg expr) { 5971 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5972 5973 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5974 Loc, AsmString); 5975 CurContext->addDecl(New); 5976 return DeclPtrTy::make(New); 5977} 5978 5979void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5980 SourceLocation PragmaLoc, 5981 SourceLocation NameLoc) { 5982 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5983 5984 if (PrevDecl) { 5985 PrevDecl->addAttr(::new (Context) WeakAttr()); 5986 } else { 5987 (void)WeakUndeclaredIdentifiers.insert( 5988 std::pair<IdentifierInfo*,WeakInfo> 5989 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5990 } 5991} 5992 5993void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5994 IdentifierInfo* AliasName, 5995 SourceLocation PragmaLoc, 5996 SourceLocation NameLoc, 5997 SourceLocation AliasNameLoc) { 5998 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5999 WeakInfo W = WeakInfo(Name, NameLoc); 6000 6001 if (PrevDecl) { 6002 if (!PrevDecl->hasAttr<AliasAttr>()) 6003 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 6004 DeclApplyPragmaWeak(TUScope, ND, W); 6005 } else { 6006 (void)WeakUndeclaredIdentifiers.insert( 6007 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 6008 } 6009} 6010