SemaDecl.cpp revision 4325d1ed52ccd5d7ead92d398f395bc8b143befe
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 "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/BitVector.h" 34#include "llvm/ADT/STLExtras.h" 35#include <algorithm> 36#include <cstring> 37#include <functional> 38#include <queue> 39using namespace clang; 40 41/// getDeclName - Return a pretty name for the specified decl if possible, or 42/// an empty string if not. This is used for pretty crash reporting. 43std::string Sema::getDeclName(DeclPtrTy d) { 44 Decl *D = d.getAs<Decl>(); 45 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 46 return DN->getQualifiedNameAsString(); 47 return ""; 48} 49 50Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 51 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 52} 53 54/// \brief If the identifier refers to a type name within this scope, 55/// return the declaration of that type. 56/// 57/// This routine performs ordinary name lookup of the identifier II 58/// within the given scope, with optional C++ scope specifier SS, to 59/// determine whether the name refers to a type. If so, returns an 60/// opaque pointer (actually a QualType) corresponding to that 61/// type. Otherwise, returns NULL. 62/// 63/// If name lookup results in an ambiguity, this routine will complain 64/// and then return NULL. 65Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 66 Scope *S, const CXXScopeSpec *SS, 67 bool isClassName) { 68 // C++ [temp.res]p3: 69 // A qualified-id that refers to a type and in which the 70 // nested-name-specifier depends on a template-parameter (14.6.2) 71 // shall be prefixed by the keyword typename to indicate that the 72 // qualified-id denotes a type, forming an 73 // elaborated-type-specifier (7.1.5.3). 74 // 75 // We therefore do not perform any name lookup if the result would 76 // refer to a member of an unknown specialization. 77 if (SS && isUnknownSpecialization(*SS)) { 78 if (!isClassName) 79 return 0; 80 81 // We know from the grammar that this name refers to a type, so build a 82 // TypenameType node to describe the type. 83 // FIXME: Record somewhere that this TypenameType node has no "typename" 84 // keyword associated with it. 85 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 86 II, SS->getRange()).getAsOpaquePtr(); 87 } 88 89 LookupResult Result; 90 LookupParsedName(Result, S, SS, &II, LookupOrdinaryName, false, false); 91 92 NamedDecl *IIDecl = 0; 93 switch (Result.getKind()) { 94 case LookupResult::NotFound: 95 case LookupResult::FoundOverloaded: 96 return 0; 97 98 case LookupResult::Ambiguous: 99 // Recover from type-hiding ambiguities by hiding the type. We'll 100 // do the lookup again when looking for an object, and we can 101 // diagnose the error then. If we don't do this, then the error 102 // about hiding the type will be immediately followed by an error 103 // that only makes sense if the identifier was treated like a type. 104 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) 105 return 0; 106 107 // Look to see if we have a type anywhere in the list of results. 108 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 109 Res != ResEnd; ++Res) { 110 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 111 if (!IIDecl || 112 (*Res)->getLocation().getRawEncoding() < 113 IIDecl->getLocation().getRawEncoding()) 114 IIDecl = *Res; 115 } 116 } 117 118 if (!IIDecl) { 119 // None of the entities we found is a type, so there is no way 120 // to even assume that the result is a type. In this case, don't 121 // complain about the ambiguity. The parser will either try to 122 // perform this lookup again (e.g., as an object name), which 123 // will produce the ambiguity, or will complain that it expected 124 // a type name. 125 return 0; 126 } 127 128 // We found a type within the ambiguous lookup; diagnose the 129 // ambiguity and then return that type. This might be the right 130 // answer, or it might not be, but it suppresses any attempt to 131 // perform the name lookup again. 132 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 133 break; 134 135 case LookupResult::Found: 136 IIDecl = Result.getFoundDecl(); 137 break; 138 } 139 140 assert(IIDecl && "Didn't find decl"); 141 142 QualType T; 143 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 144 DiagnoseUseOfDecl(IIDecl, NameLoc); 145 146 // C++ [temp.local]p2: 147 // Within the scope of a class template specialization or 148 // partial specialization, when the injected-class-name is 149 // not followed by a <, it is equivalent to the 150 // injected-class-name followed by the template-argument s 151 // of the class template specialization or partial 152 // specialization enclosed in <>. 153 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 154 if (RD->isInjectedClassName()) 155 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 156 T = Template->getInjectedClassNameType(Context); 157 158 if (T.isNull()) 159 T = Context.getTypeDeclType(TD); 160 161 if (SS) 162 T = getQualifiedNameType(*SS, T); 163 164 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 165 DiagnoseUseOfDecl(IIDecl, NameLoc); 166 T = Context.getObjCInterfaceType(IDecl); 167 } else 168 return 0; 169 170 return T.getAsOpaquePtr(); 171} 172 173/// isTagName() - This method is called *for error recovery purposes only* 174/// to determine if the specified name is a valid tag name ("struct foo"). If 175/// so, this returns the TST for the tag corresponding to it (TST_enum, 176/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 177/// where the user forgot to specify the tag. 178DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 179 // Do a tag name lookup in this scope. 180 LookupResult R; 181 LookupName(R, S, &II, LookupTagName, false, false); 182 if (R.getKind() == LookupResult::Found) 183 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 184 switch (TD->getTagKind()) { 185 case TagDecl::TK_struct: return DeclSpec::TST_struct; 186 case TagDecl::TK_union: return DeclSpec::TST_union; 187 case TagDecl::TK_class: return DeclSpec::TST_class; 188 case TagDecl::TK_enum: return DeclSpec::TST_enum; 189 } 190 } 191 192 return DeclSpec::TST_unspecified; 193} 194 195bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 196 SourceLocation IILoc, 197 Scope *S, 198 const CXXScopeSpec *SS, 199 TypeTy *&SuggestedType) { 200 // We don't have anything to suggest (yet). 201 SuggestedType = 0; 202 203 // FIXME: Should we move the logic that tries to recover from a missing tag 204 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 205 206 if (!SS) 207 Diag(IILoc, diag::err_unknown_typename) << &II; 208 else if (DeclContext *DC = computeDeclContext(*SS, false)) 209 Diag(IILoc, diag::err_typename_nested_not_found) 210 << &II << DC << SS->getRange(); 211 else if (isDependentScopeSpecifier(*SS)) { 212 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 213 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 214 << SourceRange(SS->getRange().getBegin(), IILoc) 215 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 216 "typename "); 217 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 218 } else { 219 assert(SS && SS->isInvalid() && 220 "Invalid scope specifier has already been diagnosed"); 221 } 222 223 return true; 224} 225 226// Determines the context to return to after temporarily entering a 227// context. This depends in an unnecessarily complicated way on the 228// exact ordering of callbacks from the parser. 229DeclContext *Sema::getContainingDC(DeclContext *DC) { 230 231 // Functions defined inline within classes aren't parsed until we've 232 // finished parsing the top-level class, so the top-level class is 233 // the context we'll need to return to. 234 if (isa<FunctionDecl>(DC)) { 235 DC = DC->getLexicalParent(); 236 237 // A function not defined within a class will always return to its 238 // lexical context. 239 if (!isa<CXXRecordDecl>(DC)) 240 return DC; 241 242 // A C++ inline method/friend is parsed *after* the topmost class 243 // it was declared in is fully parsed ("complete"); the topmost 244 // class is the context we need to return to. 245 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 246 DC = RD; 247 248 // Return the declaration context of the topmost class the inline method is 249 // declared in. 250 return DC; 251 } 252 253 if (isa<ObjCMethodDecl>(DC)) 254 return Context.getTranslationUnitDecl(); 255 256 return DC->getLexicalParent(); 257} 258 259void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 260 assert(getContainingDC(DC) == CurContext && 261 "The next DeclContext should be lexically contained in the current one."); 262 CurContext = DC; 263 S->setEntity(DC); 264} 265 266void Sema::PopDeclContext() { 267 assert(CurContext && "DeclContext imbalance!"); 268 269 CurContext = getContainingDC(CurContext); 270} 271 272/// EnterDeclaratorContext - Used when we must lookup names in the context 273/// of a declarator's nested name specifier. 274void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 275 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 276 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 277 CurContext = DC; 278 assert(CurContext && "No context?"); 279 S->setEntity(CurContext); 280} 281 282void Sema::ExitDeclaratorContext(Scope *S) { 283 S->setEntity(PreDeclaratorDC); 284 PreDeclaratorDC = 0; 285 286 // Reset CurContext to the nearest enclosing context. 287 while (!S->getEntity() && S->getParent()) 288 S = S->getParent(); 289 CurContext = static_cast<DeclContext*>(S->getEntity()); 290 assert(CurContext && "No context?"); 291} 292 293/// \brief Determine whether we allow overloading of the function 294/// PrevDecl with another declaration. 295/// 296/// This routine determines whether overloading is possible, not 297/// whether some new function is actually an overload. It will return 298/// true in C++ (where we can always provide overloads) or, as an 299/// extension, in C when the previous function is already an 300/// overloaded function declaration or has the "overloadable" 301/// attribute. 302static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 303 if (Context.getLangOptions().CPlusPlus) 304 return true; 305 306 if (isa<OverloadedFunctionDecl>(PrevDecl)) 307 return true; 308 309 return PrevDecl->getAttr<OverloadableAttr>() != 0; 310} 311 312/// Add this decl to the scope shadowed decl chains. 313void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 314 // Move up the scope chain until we find the nearest enclosing 315 // non-transparent context. The declaration will be introduced into this 316 // scope. 317 while (S->getEntity() && 318 ((DeclContext *)S->getEntity())->isTransparentContext()) 319 S = S->getParent(); 320 321 // Add scoped declarations into their context, so that they can be 322 // found later. Declarations without a context won't be inserted 323 // into any context. 324 if (AddToContext) 325 CurContext->addDecl(D); 326 327 // Out-of-line function and variable definitions should not be pushed into 328 // scope. 329 if ((isa<FunctionTemplateDecl>(D) && 330 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 331 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 332 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 333 return; 334 335 // If this replaces anything in the current scope, 336 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 337 IEnd = IdResolver.end(); 338 for (; I != IEnd; ++I) { 339 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 340 S->RemoveDecl(DeclPtrTy::make(*I)); 341 IdResolver.RemoveDecl(*I); 342 343 // Should only need to replace one decl. 344 break; 345 } 346 } 347 348 S->AddDecl(DeclPtrTy::make(D)); 349 IdResolver.AddDecl(D); 350} 351 352bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 353 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 354 // Look inside the overload set to determine if any of the declarations 355 // are in scope. (Possibly) build a new overload set containing only 356 // those declarations that are in scope. 357 OverloadedFunctionDecl *NewOvl = 0; 358 bool FoundInScope = false; 359 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 360 FEnd = Ovl->function_end(); 361 F != FEnd; ++F) { 362 NamedDecl *FD = F->get(); 363 if (!isDeclInScope(FD, Ctx, S)) { 364 if (!NewOvl && F != Ovl->function_begin()) { 365 NewOvl = OverloadedFunctionDecl::Create(Context, 366 F->get()->getDeclContext(), 367 F->get()->getDeclName()); 368 D = NewOvl; 369 for (OverloadedFunctionDecl::function_iterator 370 First = Ovl->function_begin(); 371 First != F; ++First) 372 NewOvl->addOverload(*First); 373 } 374 } else { 375 FoundInScope = true; 376 if (NewOvl) 377 NewOvl->addOverload(*F); 378 } 379 } 380 381 return FoundInScope; 382 } 383 384 return IdResolver.isDeclInScope(D, Ctx, Context, S); 385} 386 387static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 388 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 389 return false; 390 391 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 392 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 393 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 394 if (!RD->hasTrivialConstructor()) 395 return false; 396 if (!RD->hasTrivialDestructor()) 397 return false; 398 } 399 } 400 } 401 402 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 403 !isa<ImplicitParamDecl>(D) && 404 D->getDeclContext()->isFunctionOrMethod()); 405} 406 407void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 408 if (S->decl_empty()) return; 409 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 410 "Scope shouldn't contain decls!"); 411 412 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 413 I != E; ++I) { 414 Decl *TmpD = (*I).getAs<Decl>(); 415 assert(TmpD && "This decl didn't get pushed??"); 416 417 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 418 NamedDecl *D = cast<NamedDecl>(TmpD); 419 420 if (!D->getDeclName()) continue; 421 422 // Diagnose unused variables in this scope. 423 if (ShouldDiagnoseUnusedDecl(D)) 424 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 425 426 // Remove this name from our lexical scope. 427 IdResolver.RemoveDecl(D); 428 } 429} 430 431/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 432/// return 0 if one not found. 433ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 434 // The third "scope" argument is 0 since we aren't enabling lazy built-in 435 // creation from this context. 436 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 437 438 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 439} 440 441/// getNonFieldDeclScope - Retrieves the innermost scope, starting 442/// from S, where a non-field would be declared. This routine copes 443/// with the difference between C and C++ scoping rules in structs and 444/// unions. For example, the following code is well-formed in C but 445/// ill-formed in C++: 446/// @code 447/// struct S6 { 448/// enum { BAR } e; 449/// }; 450/// 451/// void test_S6() { 452/// struct S6 a; 453/// a.e = BAR; 454/// } 455/// @endcode 456/// For the declaration of BAR, this routine will return a different 457/// scope. The scope S will be the scope of the unnamed enumeration 458/// within S6. In C++, this routine will return the scope associated 459/// with S6, because the enumeration's scope is a transparent 460/// context but structures can contain non-field names. In C, this 461/// routine will return the translation unit scope, since the 462/// enumeration's scope is a transparent context and structures cannot 463/// contain non-field names. 464Scope *Sema::getNonFieldDeclScope(Scope *S) { 465 while (((S->getFlags() & Scope::DeclScope) == 0) || 466 (S->getEntity() && 467 ((DeclContext *)S->getEntity())->isTransparentContext()) || 468 (S->isClassScope() && !getLangOptions().CPlusPlus)) 469 S = S->getParent(); 470 return S; 471} 472 473void Sema::InitBuiltinVaListType() { 474 if (!Context.getBuiltinVaListType().isNull()) 475 return; 476 477 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 478 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 479 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 480 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 481} 482 483/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 484/// file scope. lazily create a decl for it. ForRedeclaration is true 485/// if we're creating this built-in in anticipation of redeclaring the 486/// built-in. 487NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 488 Scope *S, bool ForRedeclaration, 489 SourceLocation Loc) { 490 Builtin::ID BID = (Builtin::ID)bid; 491 492 if (Context.BuiltinInfo.hasVAListUse(BID)) 493 InitBuiltinVaListType(); 494 495 ASTContext::GetBuiltinTypeError Error; 496 QualType R = Context.GetBuiltinType(BID, Error); 497 switch (Error) { 498 case ASTContext::GE_None: 499 // Okay 500 break; 501 502 case ASTContext::GE_Missing_stdio: 503 if (ForRedeclaration) 504 Diag(Loc, diag::err_implicit_decl_requires_stdio) 505 << Context.BuiltinInfo.GetName(BID); 506 return 0; 507 508 case ASTContext::GE_Missing_setjmp: 509 if (ForRedeclaration) 510 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 511 << Context.BuiltinInfo.GetName(BID); 512 return 0; 513 } 514 515 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 516 Diag(Loc, diag::ext_implicit_lib_function_decl) 517 << Context.BuiltinInfo.GetName(BID) 518 << R; 519 if (Context.BuiltinInfo.getHeaderName(BID) && 520 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 521 != Diagnostic::Ignored) 522 Diag(Loc, diag::note_please_include_header) 523 << Context.BuiltinInfo.getHeaderName(BID) 524 << Context.BuiltinInfo.GetName(BID); 525 } 526 527 FunctionDecl *New = FunctionDecl::Create(Context, 528 Context.getTranslationUnitDecl(), 529 Loc, II, R, /*DInfo=*/0, 530 FunctionDecl::Extern, false, 531 /*hasPrototype=*/true); 532 New->setImplicit(); 533 534 // Create Decl objects for each parameter, adding them to the 535 // FunctionDecl. 536 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 537 llvm::SmallVector<ParmVarDecl*, 16> Params; 538 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 539 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 540 FT->getArgType(i), /*DInfo=*/0, 541 VarDecl::None, 0)); 542 New->setParams(Context, Params.data(), Params.size()); 543 } 544 545 AddKnownFunctionAttributes(New); 546 547 // TUScope is the translation-unit scope to insert this function into. 548 // FIXME: This is hideous. We need to teach PushOnScopeChains to 549 // relate Scopes to DeclContexts, and probably eliminate CurContext 550 // entirely, but we're not there yet. 551 DeclContext *SavedContext = CurContext; 552 CurContext = Context.getTranslationUnitDecl(); 553 PushOnScopeChains(New, TUScope); 554 CurContext = SavedContext; 555 return New; 556} 557 558/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 559/// same name and scope as a previous declaration 'Old'. Figure out 560/// how to resolve this situation, merging decls or emitting 561/// diagnostics as appropriate. If there was an error, set New to be invalid. 562/// 563void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 564 // If either decl is known invalid already, set the new one to be invalid and 565 // don't bother doing any merging checks. 566 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 567 return New->setInvalidDecl(); 568 569 // Allow multiple definitions for ObjC built-in typedefs. 570 // FIXME: Verify the underlying types are equivalent! 571 if (getLangOptions().ObjC1) { 572 const IdentifierInfo *TypeID = New->getIdentifier(); 573 switch (TypeID->getLength()) { 574 default: break; 575 case 2: 576 if (!TypeID->isStr("id")) 577 break; 578 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 579 // Install the built-in type for 'id', ignoring the current definition. 580 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 581 return; 582 case 5: 583 if (!TypeID->isStr("Class")) 584 break; 585 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 586 // Install the built-in type for 'Class', ignoring the current definition. 587 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 588 return; 589 case 3: 590 if (!TypeID->isStr("SEL")) 591 break; 592 Context.setObjCSelType(Context.getTypeDeclType(New)); 593 return; 594 case 8: 595 if (!TypeID->isStr("Protocol")) 596 break; 597 Context.setObjCProtoType(New->getUnderlyingType()); 598 return; 599 } 600 // Fall through - the typedef name was not a builtin type. 601 } 602 // Verify the old decl was also a type. 603 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 604 if (!Old) { 605 Diag(New->getLocation(), diag::err_redefinition_different_kind) 606 << New->getDeclName(); 607 if (OldD->getLocation().isValid()) 608 Diag(OldD->getLocation(), diag::note_previous_definition); 609 return New->setInvalidDecl(); 610 } 611 612 // Determine the "old" type we'll use for checking and diagnostics. 613 QualType OldType; 614 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 615 OldType = OldTypedef->getUnderlyingType(); 616 else 617 OldType = Context.getTypeDeclType(Old); 618 619 // If the typedef types are not identical, reject them in all languages and 620 // with any extensions enabled. 621 622 if (OldType != New->getUnderlyingType() && 623 Context.getCanonicalType(OldType) != 624 Context.getCanonicalType(New->getUnderlyingType())) { 625 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 626 << New->getUnderlyingType() << OldType; 627 if (Old->getLocation().isValid()) 628 Diag(Old->getLocation(), diag::note_previous_definition); 629 return New->setInvalidDecl(); 630 } 631 632 if (getLangOptions().Microsoft) 633 return; 634 635 // C++ [dcl.typedef]p2: 636 // In a given non-class scope, a typedef specifier can be used to 637 // redefine the name of any type declared in that scope to refer 638 // to the type to which it already refers. 639 if (getLangOptions().CPlusPlus) { 640 if (!isa<CXXRecordDecl>(CurContext)) 641 return; 642 Diag(New->getLocation(), diag::err_redefinition) 643 << New->getDeclName(); 644 Diag(Old->getLocation(), diag::note_previous_definition); 645 return New->setInvalidDecl(); 646 } 647 648 // If we have a redefinition of a typedef in C, emit a warning. This warning 649 // is normally mapped to an error, but can be controlled with 650 // -Wtypedef-redefinition. If either the original or the redefinition is 651 // in a system header, don't emit this for compatibility with GCC. 652 if (PP.getDiagnostics().getSuppressSystemWarnings() && 653 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 654 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 655 return; 656 657 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 658 << New->getDeclName(); 659 Diag(Old->getLocation(), diag::note_previous_definition); 660 return; 661} 662 663/// DeclhasAttr - returns true if decl Declaration already has the target 664/// attribute. 665static bool 666DeclHasAttr(const Decl *decl, const Attr *target) { 667 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 668 if (attr->getKind() == target->getKind()) 669 return true; 670 671 return false; 672} 673 674/// MergeAttributes - append attributes from the Old decl to the New one. 675static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 676 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 677 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 678 Attr *NewAttr = attr->clone(C); 679 NewAttr->setInherited(true); 680 New->addAttr(NewAttr); 681 } 682 } 683} 684 685/// Used in MergeFunctionDecl to keep track of function parameters in 686/// C. 687struct GNUCompatibleParamWarning { 688 ParmVarDecl *OldParm; 689 ParmVarDecl *NewParm; 690 QualType PromotedType; 691}; 692 693/// MergeFunctionDecl - We just parsed a function 'New' from 694/// declarator D which has the same name and scope as a previous 695/// declaration 'Old'. Figure out how to resolve this situation, 696/// merging decls or emitting diagnostics as appropriate. 697/// 698/// In C++, New and Old must be declarations that are not 699/// overloaded. Use IsOverload to determine whether New and Old are 700/// overloaded, and to select the Old declaration that New should be 701/// merged with. 702/// 703/// Returns true if there was an error, false otherwise. 704bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 705 assert(!isa<OverloadedFunctionDecl>(OldD) && 706 "Cannot merge with an overloaded function declaration"); 707 708 // Verify the old decl was also a function. 709 FunctionDecl *Old = 0; 710 if (FunctionTemplateDecl *OldFunctionTemplate 711 = dyn_cast<FunctionTemplateDecl>(OldD)) 712 Old = OldFunctionTemplate->getTemplatedDecl(); 713 else 714 Old = dyn_cast<FunctionDecl>(OldD); 715 if (!Old) { 716 Diag(New->getLocation(), diag::err_redefinition_different_kind) 717 << New->getDeclName(); 718 Diag(OldD->getLocation(), diag::note_previous_definition); 719 return true; 720 } 721 722 // Determine whether the previous declaration was a definition, 723 // implicit declaration, or a declaration. 724 diag::kind PrevDiag; 725 if (Old->isThisDeclarationADefinition()) 726 PrevDiag = diag::note_previous_definition; 727 else if (Old->isImplicit()) 728 PrevDiag = diag::note_previous_implicit_declaration; 729 else 730 PrevDiag = diag::note_previous_declaration; 731 732 QualType OldQType = Context.getCanonicalType(Old->getType()); 733 QualType NewQType = Context.getCanonicalType(New->getType()); 734 735 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 736 New->getStorageClass() == FunctionDecl::Static && 737 Old->getStorageClass() != FunctionDecl::Static) { 738 Diag(New->getLocation(), diag::err_static_non_static) 739 << New; 740 Diag(Old->getLocation(), PrevDiag); 741 return true; 742 } 743 744 if (getLangOptions().CPlusPlus) { 745 // (C++98 13.1p2): 746 // Certain function declarations cannot be overloaded: 747 // -- Function declarations that differ only in the return type 748 // cannot be overloaded. 749 QualType OldReturnType 750 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 751 QualType NewReturnType 752 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 753 if (OldReturnType != NewReturnType) { 754 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 755 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 756 return true; 757 } 758 759 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 760 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 761 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 762 NewMethod->getLexicalDeclContext()->isRecord()) { 763 // -- Member function declarations with the same name and the 764 // same parameter types cannot be overloaded if any of them 765 // is a static member function declaration. 766 if (OldMethod->isStatic() || NewMethod->isStatic()) { 767 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 768 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 769 return true; 770 } 771 772 // C++ [class.mem]p1: 773 // [...] A member shall not be declared twice in the 774 // member-specification, except that a nested class or member 775 // class template can be declared and then later defined. 776 unsigned NewDiag; 777 if (isa<CXXConstructorDecl>(OldMethod)) 778 NewDiag = diag::err_constructor_redeclared; 779 else if (isa<CXXDestructorDecl>(NewMethod)) 780 NewDiag = diag::err_destructor_redeclared; 781 else if (isa<CXXConversionDecl>(NewMethod)) 782 NewDiag = diag::err_conv_function_redeclared; 783 else 784 NewDiag = diag::err_member_redeclared; 785 786 Diag(New->getLocation(), NewDiag); 787 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 788 } 789 790 // (C++98 8.3.5p3): 791 // All declarations for a function shall agree exactly in both the 792 // return type and the parameter-type-list. 793 if (OldQType == NewQType) 794 return MergeCompatibleFunctionDecls(New, Old); 795 796 // Fall through for conflicting redeclarations and redefinitions. 797 } 798 799 // C: Function types need to be compatible, not identical. This handles 800 // duplicate function decls like "void f(int); void f(enum X);" properly. 801 if (!getLangOptions().CPlusPlus && 802 Context.typesAreCompatible(OldQType, NewQType)) { 803 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 804 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 805 const FunctionProtoType *OldProto = 0; 806 if (isa<FunctionNoProtoType>(NewFuncType) && 807 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 808 // The old declaration provided a function prototype, but the 809 // new declaration does not. Merge in the prototype. 810 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 811 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 812 OldProto->arg_type_end()); 813 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 814 ParamTypes.data(), ParamTypes.size(), 815 OldProto->isVariadic(), 816 OldProto->getTypeQuals()); 817 New->setType(NewQType); 818 New->setHasInheritedPrototype(); 819 820 // Synthesize a parameter for each argument type. 821 llvm::SmallVector<ParmVarDecl*, 16> Params; 822 for (FunctionProtoType::arg_type_iterator 823 ParamType = OldProto->arg_type_begin(), 824 ParamEnd = OldProto->arg_type_end(); 825 ParamType != ParamEnd; ++ParamType) { 826 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 827 SourceLocation(), 0, 828 *ParamType, /*DInfo=*/0, 829 VarDecl::None, 0); 830 Param->setImplicit(); 831 Params.push_back(Param); 832 } 833 834 New->setParams(Context, Params.data(), Params.size()); 835 } 836 837 return MergeCompatibleFunctionDecls(New, Old); 838 } 839 840 // GNU C permits a K&R definition to follow a prototype declaration 841 // if the declared types of the parameters in the K&R definition 842 // match the types in the prototype declaration, even when the 843 // promoted types of the parameters from the K&R definition differ 844 // from the types in the prototype. GCC then keeps the types from 845 // the prototype. 846 // 847 // If a variadic prototype is followed by a non-variadic K&R definition, 848 // the K&R definition becomes variadic. This is sort of an edge case, but 849 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 850 // C99 6.9.1p8. 851 if (!getLangOptions().CPlusPlus && 852 Old->hasPrototype() && !New->hasPrototype() && 853 New->getType()->getAs<FunctionProtoType>() && 854 Old->getNumParams() == New->getNumParams()) { 855 llvm::SmallVector<QualType, 16> ArgTypes; 856 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 857 const FunctionProtoType *OldProto 858 = Old->getType()->getAs<FunctionProtoType>(); 859 const FunctionProtoType *NewProto 860 = New->getType()->getAs<FunctionProtoType>(); 861 862 // Determine whether this is the GNU C extension. 863 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 864 NewProto->getResultType()); 865 bool LooseCompatible = !MergedReturn.isNull(); 866 for (unsigned Idx = 0, End = Old->getNumParams(); 867 LooseCompatible && Idx != End; ++Idx) { 868 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 869 ParmVarDecl *NewParm = New->getParamDecl(Idx); 870 if (Context.typesAreCompatible(OldParm->getType(), 871 NewProto->getArgType(Idx))) { 872 ArgTypes.push_back(NewParm->getType()); 873 } else if (Context.typesAreCompatible(OldParm->getType(), 874 NewParm->getType())) { 875 GNUCompatibleParamWarning Warn 876 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 877 Warnings.push_back(Warn); 878 ArgTypes.push_back(NewParm->getType()); 879 } else 880 LooseCompatible = false; 881 } 882 883 if (LooseCompatible) { 884 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 885 Diag(Warnings[Warn].NewParm->getLocation(), 886 diag::ext_param_promoted_not_compatible_with_prototype) 887 << Warnings[Warn].PromotedType 888 << Warnings[Warn].OldParm->getType(); 889 Diag(Warnings[Warn].OldParm->getLocation(), 890 diag::note_previous_declaration); 891 } 892 893 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 894 ArgTypes.size(), 895 OldProto->isVariadic(), 0)); 896 return MergeCompatibleFunctionDecls(New, Old); 897 } 898 899 // Fall through to diagnose conflicting types. 900 } 901 902 // A function that has already been declared has been redeclared or defined 903 // with a different type- show appropriate diagnostic 904 if (unsigned BuiltinID = Old->getBuiltinID()) { 905 // The user has declared a builtin function with an incompatible 906 // signature. 907 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 908 // The function the user is redeclaring is a library-defined 909 // function like 'malloc' or 'printf'. Warn about the 910 // redeclaration, then pretend that we don't know about this 911 // library built-in. 912 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 913 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 914 << Old << Old->getType(); 915 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 916 Old->setInvalidDecl(); 917 return false; 918 } 919 920 PrevDiag = diag::note_previous_builtin_declaration; 921 } 922 923 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 924 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 925 return true; 926} 927 928/// \brief Completes the merge of two function declarations that are 929/// known to be compatible. 930/// 931/// This routine handles the merging of attributes and other 932/// properties of function declarations form the old declaration to 933/// the new declaration, once we know that New is in fact a 934/// redeclaration of Old. 935/// 936/// \returns false 937bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 938 // Merge the attributes 939 MergeAttributes(New, Old, Context); 940 941 // Merge the storage class. 942 if (Old->getStorageClass() != FunctionDecl::Extern && 943 Old->getStorageClass() != FunctionDecl::None) 944 New->setStorageClass(Old->getStorageClass()); 945 946 // Merge "pure" flag. 947 if (Old->isPure()) 948 New->setPure(); 949 950 // Merge the "deleted" flag. 951 if (Old->isDeleted()) 952 New->setDeleted(); 953 954 if (getLangOptions().CPlusPlus) 955 return MergeCXXFunctionDecl(New, Old); 956 957 return false; 958} 959 960/// MergeVarDecl - We just parsed a variable 'New' which has the same name 961/// and scope as a previous declaration 'Old'. Figure out how to resolve this 962/// situation, merging decls or emitting diagnostics as appropriate. 963/// 964/// Tentative definition rules (C99 6.9.2p2) are checked by 965/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 966/// definitions here, since the initializer hasn't been attached. 967/// 968void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 969 // If either decl is invalid, make sure the new one is marked invalid and 970 // don't do any other checking. 971 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 972 return New->setInvalidDecl(); 973 974 // Verify the old decl was also a variable. 975 VarDecl *Old = dyn_cast<VarDecl>(OldD); 976 if (!Old) { 977 Diag(New->getLocation(), diag::err_redefinition_different_kind) 978 << New->getDeclName(); 979 Diag(OldD->getLocation(), diag::note_previous_definition); 980 return New->setInvalidDecl(); 981 } 982 983 MergeAttributes(New, Old, Context); 984 985 // Merge the types 986 QualType MergedT; 987 if (getLangOptions().CPlusPlus) { 988 if (Context.hasSameType(New->getType(), Old->getType())) 989 MergedT = New->getType(); 990 // C++ [basic.types]p7: 991 // [...] The declared type of an array object might be an array of 992 // unknown size and therefore be incomplete at one point in a 993 // translation unit and complete later on; [...] 994 else if (Old->getType()->isIncompleteArrayType() && 995 New->getType()->isArrayType()) { 996 CanQual<ArrayType> OldArray 997 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 998 CanQual<ArrayType> NewArray 999 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1000 if (OldArray->getElementType() == NewArray->getElementType()) 1001 MergedT = New->getType(); 1002 } 1003 } else { 1004 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1005 } 1006 if (MergedT.isNull()) { 1007 Diag(New->getLocation(), diag::err_redefinition_different_type) 1008 << New->getDeclName(); 1009 Diag(Old->getLocation(), diag::note_previous_definition); 1010 return New->setInvalidDecl(); 1011 } 1012 New->setType(MergedT); 1013 1014 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1015 if (New->getStorageClass() == VarDecl::Static && 1016 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1017 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1018 Diag(Old->getLocation(), diag::note_previous_definition); 1019 return New->setInvalidDecl(); 1020 } 1021 // C99 6.2.2p4: 1022 // For an identifier declared with the storage-class specifier 1023 // extern in a scope in which a prior declaration of that 1024 // identifier is visible,23) if the prior declaration specifies 1025 // internal or external linkage, the linkage of the identifier at 1026 // the later declaration is the same as the linkage specified at 1027 // the prior declaration. If no prior declaration is visible, or 1028 // if the prior declaration specifies no linkage, then the 1029 // identifier has external linkage. 1030 if (New->hasExternalStorage() && Old->hasLinkage()) 1031 /* Okay */; 1032 else if (New->getStorageClass() != VarDecl::Static && 1033 Old->getStorageClass() == VarDecl::Static) { 1034 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1035 Diag(Old->getLocation(), diag::note_previous_definition); 1036 return New->setInvalidDecl(); 1037 } 1038 1039 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1040 1041 // FIXME: The test for external storage here seems wrong? We still 1042 // need to check for mismatches. 1043 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1044 // Don't complain about out-of-line definitions of static members. 1045 !(Old->getLexicalDeclContext()->isRecord() && 1046 !New->getLexicalDeclContext()->isRecord())) { 1047 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1048 Diag(Old->getLocation(), diag::note_previous_definition); 1049 return New->setInvalidDecl(); 1050 } 1051 1052 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1053 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1054 Diag(Old->getLocation(), diag::note_previous_definition); 1055 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1056 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1057 Diag(Old->getLocation(), diag::note_previous_definition); 1058 } 1059 1060 // Keep a chain of previous declarations. 1061 New->setPreviousDeclaration(Old); 1062} 1063 1064/// CheckFallThrough - Check that we don't fall off the end of a 1065/// Statement that should return a value. 1066/// 1067/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1068/// MaybeFallThrough iff we might or might not fall off the end, 1069/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1070/// return. We assume NeverFallThrough iff we never fall off the end of the 1071/// statement but we may return. We assume that functions not marked noreturn 1072/// will return. 1073Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1074 // FIXME: Eventually share this CFG object when we have other warnings based 1075 // of the CFG. This can be done using AnalysisContext. 1076 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1077 1078 // FIXME: They should never return 0, fix that, delete this code. 1079 if (cfg == 0) 1080 // FIXME: This should be NeverFallThrough 1081 return NeverFallThroughOrReturn; 1082 // The CFG leaves in dead things, and we don't want to dead code paths to 1083 // confuse us, so we mark all live things first. 1084 std::queue<CFGBlock*> workq; 1085 llvm::BitVector live(cfg->getNumBlockIDs()); 1086 // Prep work queue 1087 workq.push(&cfg->getEntry()); 1088 // Solve 1089 while (!workq.empty()) { 1090 CFGBlock *item = workq.front(); 1091 workq.pop(); 1092 live.set(item->getBlockID()); 1093 for (CFGBlock::succ_iterator I=item->succ_begin(), 1094 E=item->succ_end(); 1095 I != E; 1096 ++I) { 1097 if ((*I) && !live[(*I)->getBlockID()]) { 1098 live.set((*I)->getBlockID()); 1099 workq.push(*I); 1100 } 1101 } 1102 } 1103 1104 // Now we know what is live, we check the live precessors of the exit block 1105 // and look for fall through paths, being careful to ignore normal returns, 1106 // and exceptional paths. 1107 bool HasLiveReturn = false; 1108 bool HasFakeEdge = false; 1109 bool HasPlainEdge = false; 1110 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1111 E = cfg->getExit().pred_end(); 1112 I != E; 1113 ++I) { 1114 CFGBlock& B = **I; 1115 if (!live[B.getBlockID()]) 1116 continue; 1117 if (B.size() == 0) { 1118 // A labeled empty statement, or the entry block... 1119 HasPlainEdge = true; 1120 continue; 1121 } 1122 Stmt *S = B[B.size()-1]; 1123 if (isa<ReturnStmt>(S)) { 1124 HasLiveReturn = true; 1125 continue; 1126 } 1127 if (isa<ObjCAtThrowStmt>(S)) { 1128 HasFakeEdge = true; 1129 continue; 1130 } 1131 if (isa<CXXThrowExpr>(S)) { 1132 HasFakeEdge = true; 1133 continue; 1134 } 1135 bool NoReturnEdge = false; 1136 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1137 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1138 if (CEE->getType().getNoReturnAttr()) { 1139 NoReturnEdge = true; 1140 HasFakeEdge = true; 1141 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1142 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1143 if (FD->hasAttr<NoReturnAttr>()) { 1144 NoReturnEdge = true; 1145 HasFakeEdge = true; 1146 } 1147 } 1148 } 1149 } 1150 // FIXME: Add noreturn message sends. 1151 if (NoReturnEdge == false) 1152 HasPlainEdge = true; 1153 } 1154 if (!HasPlainEdge) { 1155 if (HasLiveReturn) 1156 return NeverFallThrough; 1157 return NeverFallThroughOrReturn; 1158 } 1159 if (HasFakeEdge || HasLiveReturn) 1160 return MaybeFallThrough; 1161 // This says AlwaysFallThrough for calls to functions that are not marked 1162 // noreturn, that don't return. If people would like this warning to be more 1163 // accurate, such functions should be marked as noreturn. 1164 return AlwaysFallThrough; 1165} 1166 1167/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1168/// function that should return a value. Check that we don't fall off the end 1169/// of a noreturn function. We assume that functions and blocks not marked 1170/// noreturn will return. 1171void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1172 // FIXME: Would be nice if we had a better way to control cascading errors, 1173 // but for now, avoid them. The problem is that when Parse sees: 1174 // int foo() { return a; } 1175 // The return is eaten and the Sema code sees just: 1176 // int foo() { } 1177 // which this code would then warn about. 1178 if (getDiagnostics().hasErrorOccurred()) 1179 return; 1180 1181 bool ReturnsVoid = false; 1182 bool HasNoReturn = false; 1183 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1184 // If the result type of the function is a dependent type, we don't know 1185 // whether it will be void or not, so don't 1186 if (FD->getResultType()->isDependentType()) 1187 return; 1188 if (FD->getResultType()->isVoidType()) 1189 ReturnsVoid = true; 1190 if (FD->hasAttr<NoReturnAttr>()) 1191 HasNoReturn = true; 1192 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1193 if (MD->getResultType()->isVoidType()) 1194 ReturnsVoid = true; 1195 if (MD->hasAttr<NoReturnAttr>()) 1196 HasNoReturn = true; 1197 } 1198 1199 // Short circuit for compilation speed. 1200 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1201 == Diagnostic::Ignored || ReturnsVoid) 1202 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1203 == Diagnostic::Ignored || !HasNoReturn) 1204 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1205 == Diagnostic::Ignored || !ReturnsVoid)) 1206 return; 1207 // FIXME: Function try block 1208 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1209 switch (CheckFallThrough(Body)) { 1210 case MaybeFallThrough: 1211 if (HasNoReturn) 1212 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1213 else if (!ReturnsVoid) 1214 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1215 break; 1216 case AlwaysFallThrough: 1217 if (HasNoReturn) 1218 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1219 else if (!ReturnsVoid) 1220 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1221 break; 1222 case NeverFallThroughOrReturn: 1223 if (ReturnsVoid && !HasNoReturn) 1224 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1225 break; 1226 case NeverFallThrough: 1227 break; 1228 } 1229 } 1230} 1231 1232/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1233/// that should return a value. Check that we don't fall off the end of a 1234/// noreturn block. We assume that functions and blocks not marked noreturn 1235/// will return. 1236void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1237 // FIXME: Would be nice if we had a better way to control cascading errors, 1238 // but for now, avoid them. The problem is that when Parse sees: 1239 // int foo() { return a; } 1240 // The return is eaten and the Sema code sees just: 1241 // int foo() { } 1242 // which this code would then warn about. 1243 if (getDiagnostics().hasErrorOccurred()) 1244 return; 1245 bool ReturnsVoid = false; 1246 bool HasNoReturn = false; 1247 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1248 if (FT->getResultType()->isVoidType()) 1249 ReturnsVoid = true; 1250 if (FT->getNoReturnAttr()) 1251 HasNoReturn = true; 1252 } 1253 1254 // Short circuit for compilation speed. 1255 if (ReturnsVoid 1256 && !HasNoReturn 1257 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1258 == Diagnostic::Ignored || !ReturnsVoid)) 1259 return; 1260 // FIXME: Funtion try block 1261 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1262 switch (CheckFallThrough(Body)) { 1263 case MaybeFallThrough: 1264 if (HasNoReturn) 1265 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1266 else if (!ReturnsVoid) 1267 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1268 break; 1269 case AlwaysFallThrough: 1270 if (HasNoReturn) 1271 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1272 else if (!ReturnsVoid) 1273 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1274 break; 1275 case NeverFallThroughOrReturn: 1276 if (ReturnsVoid) 1277 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1278 break; 1279 case NeverFallThrough: 1280 break; 1281 } 1282 } 1283} 1284 1285/// CheckParmsForFunctionDef - Check that the parameters of the given 1286/// function are appropriate for the definition of a function. This 1287/// takes care of any checks that cannot be performed on the 1288/// declaration itself, e.g., that the types of each of the function 1289/// parameters are complete. 1290bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1291 bool HasInvalidParm = false; 1292 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1293 ParmVarDecl *Param = FD->getParamDecl(p); 1294 1295 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1296 // function declarator that is part of a function definition of 1297 // that function shall not have incomplete type. 1298 // 1299 // This is also C++ [dcl.fct]p6. 1300 if (!Param->isInvalidDecl() && 1301 RequireCompleteType(Param->getLocation(), Param->getType(), 1302 diag::err_typecheck_decl_incomplete_type)) { 1303 Param->setInvalidDecl(); 1304 HasInvalidParm = true; 1305 } 1306 1307 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1308 // declaration of each parameter shall include an identifier. 1309 if (Param->getIdentifier() == 0 && 1310 !Param->isImplicit() && 1311 !getLangOptions().CPlusPlus) 1312 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1313 } 1314 1315 return HasInvalidParm; 1316} 1317 1318/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1319/// no declarator (e.g. "struct foo;") is parsed. 1320Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1321 // FIXME: Error on auto/register at file scope 1322 // FIXME: Error on inline/virtual/explicit 1323 // FIXME: Error on invalid restrict 1324 // FIXME: Warn on useless __thread 1325 // FIXME: Warn on useless const/volatile 1326 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1327 // FIXME: Warn on useless attributes 1328 Decl *TagD = 0; 1329 TagDecl *Tag = 0; 1330 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1331 DS.getTypeSpecType() == DeclSpec::TST_struct || 1332 DS.getTypeSpecType() == DeclSpec::TST_union || 1333 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1334 TagD = static_cast<Decl *>(DS.getTypeRep()); 1335 1336 if (!TagD) // We probably had an error 1337 return DeclPtrTy(); 1338 1339 // Note that the above type specs guarantee that the 1340 // type rep is a Decl, whereas in many of the others 1341 // it's a Type. 1342 Tag = dyn_cast<TagDecl>(TagD); 1343 } 1344 1345 if (DS.isFriendSpecified()) { 1346 // If we're dealing with a class template decl, assume that the 1347 // template routines are handling it. 1348 if (TagD && isa<ClassTemplateDecl>(TagD)) 1349 return DeclPtrTy(); 1350 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1351 } 1352 1353 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1354 // If there are attributes in the DeclSpec, apply them to the record. 1355 if (const AttributeList *AL = DS.getAttributes()) 1356 ProcessDeclAttributeList(S, Record, AL); 1357 1358 if (!Record->getDeclName() && Record->isDefinition() && 1359 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1360 if (getLangOptions().CPlusPlus || 1361 Record->getDeclContext()->isRecord()) 1362 return BuildAnonymousStructOrUnion(S, DS, Record); 1363 1364 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1365 << DS.getSourceRange(); 1366 } 1367 1368 // Microsoft allows unnamed struct/union fields. Don't complain 1369 // about them. 1370 // FIXME: Should we support Microsoft's extensions in this area? 1371 if (Record->getDeclName() && getLangOptions().Microsoft) 1372 return DeclPtrTy::make(Tag); 1373 } 1374 1375 if (!DS.isMissingDeclaratorOk() && 1376 DS.getTypeSpecType() != DeclSpec::TST_error) { 1377 // Warn about typedefs of enums without names, since this is an 1378 // extension in both Microsoft an GNU. 1379 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1380 Tag && isa<EnumDecl>(Tag)) { 1381 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1382 << DS.getSourceRange(); 1383 return DeclPtrTy::make(Tag); 1384 } 1385 1386 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1387 << DS.getSourceRange(); 1388 return DeclPtrTy(); 1389 } 1390 1391 return DeclPtrTy::make(Tag); 1392} 1393 1394/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1395/// anonymous struct or union AnonRecord into the owning context Owner 1396/// and scope S. This routine will be invoked just after we realize 1397/// that an unnamed union or struct is actually an anonymous union or 1398/// struct, e.g., 1399/// 1400/// @code 1401/// union { 1402/// int i; 1403/// float f; 1404/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1405/// // f into the surrounding scope.x 1406/// @endcode 1407/// 1408/// This routine is recursive, injecting the names of nested anonymous 1409/// structs/unions into the owning context and scope as well. 1410bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1411 RecordDecl *AnonRecord) { 1412 bool Invalid = false; 1413 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1414 FEnd = AnonRecord->field_end(); 1415 F != FEnd; ++F) { 1416 if ((*F)->getDeclName()) { 1417 LookupResult R; 1418 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1419 LookupOrdinaryName, true); 1420 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1421 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1422 // C++ [class.union]p2: 1423 // The names of the members of an anonymous union shall be 1424 // distinct from the names of any other entity in the 1425 // scope in which the anonymous union is declared. 1426 unsigned diagKind 1427 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1428 : diag::err_anonymous_struct_member_redecl; 1429 Diag((*F)->getLocation(), diagKind) 1430 << (*F)->getDeclName(); 1431 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1432 Invalid = true; 1433 } else { 1434 // C++ [class.union]p2: 1435 // For the purpose of name lookup, after the anonymous union 1436 // definition, the members of the anonymous union are 1437 // considered to have been defined in the scope in which the 1438 // anonymous union is declared. 1439 Owner->makeDeclVisibleInContext(*F); 1440 S->AddDecl(DeclPtrTy::make(*F)); 1441 IdResolver.AddDecl(*F); 1442 } 1443 } else if (const RecordType *InnerRecordType 1444 = (*F)->getType()->getAs<RecordType>()) { 1445 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1446 if (InnerRecord->isAnonymousStructOrUnion()) 1447 Invalid = Invalid || 1448 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1449 } 1450 } 1451 1452 return Invalid; 1453} 1454 1455/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1456/// anonymous structure or union. Anonymous unions are a C++ feature 1457/// (C++ [class.union]) and a GNU C extension; anonymous structures 1458/// are a GNU C and GNU C++ extension. 1459Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1460 RecordDecl *Record) { 1461 DeclContext *Owner = Record->getDeclContext(); 1462 1463 // Diagnose whether this anonymous struct/union is an extension. 1464 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1465 Diag(Record->getLocation(), diag::ext_anonymous_union); 1466 else if (!Record->isUnion()) 1467 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1468 1469 // C and C++ require different kinds of checks for anonymous 1470 // structs/unions. 1471 bool Invalid = false; 1472 if (getLangOptions().CPlusPlus) { 1473 const char* PrevSpec = 0; 1474 unsigned DiagID; 1475 // C++ [class.union]p3: 1476 // Anonymous unions declared in a named namespace or in the 1477 // global namespace shall be declared static. 1478 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1479 (isa<TranslationUnitDecl>(Owner) || 1480 (isa<NamespaceDecl>(Owner) && 1481 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1482 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1483 Invalid = true; 1484 1485 // Recover by adding 'static'. 1486 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1487 PrevSpec, DiagID); 1488 } 1489 // C++ [class.union]p3: 1490 // A storage class is not allowed in a declaration of an 1491 // anonymous union in a class scope. 1492 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1493 isa<RecordDecl>(Owner)) { 1494 Diag(DS.getStorageClassSpecLoc(), 1495 diag::err_anonymous_union_with_storage_spec); 1496 Invalid = true; 1497 1498 // Recover by removing the storage specifier. 1499 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1500 PrevSpec, DiagID); 1501 } 1502 1503 // C++ [class.union]p2: 1504 // The member-specification of an anonymous union shall only 1505 // define non-static data members. [Note: nested types and 1506 // functions cannot be declared within an anonymous union. ] 1507 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1508 MemEnd = Record->decls_end(); 1509 Mem != MemEnd; ++Mem) { 1510 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1511 // C++ [class.union]p3: 1512 // An anonymous union shall not have private or protected 1513 // members (clause 11). 1514 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1515 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1516 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1517 Invalid = true; 1518 } 1519 } else if ((*Mem)->isImplicit()) { 1520 // Any implicit members are fine. 1521 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1522 // This is a type that showed up in an 1523 // elaborated-type-specifier inside the anonymous struct or 1524 // union, but which actually declares a type outside of the 1525 // anonymous struct or union. It's okay. 1526 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1527 if (!MemRecord->isAnonymousStructOrUnion() && 1528 MemRecord->getDeclName()) { 1529 // This is a nested type declaration. 1530 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1531 << (int)Record->isUnion(); 1532 Invalid = true; 1533 } 1534 } else { 1535 // We have something that isn't a non-static data 1536 // member. Complain about it. 1537 unsigned DK = diag::err_anonymous_record_bad_member; 1538 if (isa<TypeDecl>(*Mem)) 1539 DK = diag::err_anonymous_record_with_type; 1540 else if (isa<FunctionDecl>(*Mem)) 1541 DK = diag::err_anonymous_record_with_function; 1542 else if (isa<VarDecl>(*Mem)) 1543 DK = diag::err_anonymous_record_with_static; 1544 Diag((*Mem)->getLocation(), DK) 1545 << (int)Record->isUnion(); 1546 Invalid = true; 1547 } 1548 } 1549 } 1550 1551 if (!Record->isUnion() && !Owner->isRecord()) { 1552 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1553 << (int)getLangOptions().CPlusPlus; 1554 Invalid = true; 1555 } 1556 1557 // Mock up a declarator. 1558 Declarator Dc(DS, Declarator::TypeNameContext); 1559 DeclaratorInfo *DInfo = 0; 1560 GetTypeForDeclarator(Dc, S, &DInfo); 1561 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1562 1563 // Create a declaration for this anonymous struct/union. 1564 NamedDecl *Anon = 0; 1565 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1566 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1567 /*IdentifierInfo=*/0, 1568 Context.getTypeDeclType(Record), 1569 DInfo, 1570 /*BitWidth=*/0, /*Mutable=*/false); 1571 Anon->setAccess(AS_public); 1572 if (getLangOptions().CPlusPlus) 1573 FieldCollector->Add(cast<FieldDecl>(Anon)); 1574 } else { 1575 VarDecl::StorageClass SC; 1576 switch (DS.getStorageClassSpec()) { 1577 default: assert(0 && "Unknown storage class!"); 1578 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1579 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1580 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1581 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1582 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1583 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1584 case DeclSpec::SCS_mutable: 1585 // mutable can only appear on non-static class members, so it's always 1586 // an error here 1587 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1588 Invalid = true; 1589 SC = VarDecl::None; 1590 break; 1591 } 1592 1593 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1594 /*IdentifierInfo=*/0, 1595 Context.getTypeDeclType(Record), 1596 DInfo, 1597 SC); 1598 } 1599 Anon->setImplicit(); 1600 1601 // Add the anonymous struct/union object to the current 1602 // context. We'll be referencing this object when we refer to one of 1603 // its members. 1604 Owner->addDecl(Anon); 1605 1606 // Inject the members of the anonymous struct/union into the owning 1607 // context and into the identifier resolver chain for name lookup 1608 // purposes. 1609 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1610 Invalid = true; 1611 1612 // Mark this as an anonymous struct/union type. Note that we do not 1613 // do this until after we have already checked and injected the 1614 // members of this anonymous struct/union type, because otherwise 1615 // the members could be injected twice: once by DeclContext when it 1616 // builds its lookup table, and once by 1617 // InjectAnonymousStructOrUnionMembers. 1618 Record->setAnonymousStructOrUnion(true); 1619 1620 if (Invalid) 1621 Anon->setInvalidDecl(); 1622 1623 return DeclPtrTy::make(Anon); 1624} 1625 1626 1627/// GetNameForDeclarator - Determine the full declaration name for the 1628/// given Declarator. 1629DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1630 return GetNameFromUnqualifiedId(D.getName()); 1631} 1632 1633/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1634DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1635 switch (Name.getKind()) { 1636 case UnqualifiedId::IK_Identifier: 1637 return DeclarationName(Name.Identifier); 1638 1639 case UnqualifiedId::IK_OperatorFunctionId: 1640 return Context.DeclarationNames.getCXXOperatorName( 1641 Name.OperatorFunctionId.Operator); 1642 1643 case UnqualifiedId::IK_ConversionFunctionId: { 1644 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1645 if (Ty.isNull()) 1646 return DeclarationName(); 1647 1648 return Context.DeclarationNames.getCXXConversionFunctionName( 1649 Context.getCanonicalType(Ty)); 1650 } 1651 1652 case UnqualifiedId::IK_ConstructorName: { 1653 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1654 if (Ty.isNull()) 1655 return DeclarationName(); 1656 1657 return Context.DeclarationNames.getCXXConstructorName( 1658 Context.getCanonicalType(Ty)); 1659 } 1660 1661 case UnqualifiedId::IK_DestructorName: { 1662 QualType Ty = GetTypeFromParser(Name.DestructorName); 1663 if (Ty.isNull()) 1664 return DeclarationName(); 1665 1666 return Context.DeclarationNames.getCXXDestructorName( 1667 Context.getCanonicalType(Ty)); 1668 } 1669 1670 case UnqualifiedId::IK_TemplateId: { 1671 TemplateName TName 1672 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1673 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1674 return Template->getDeclName(); 1675 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1676 return Ovl->getDeclName(); 1677 1678 return DeclarationName(); 1679 } 1680 } 1681 1682 assert(false && "Unknown name kind"); 1683 return DeclarationName(); 1684} 1685 1686/// isNearlyMatchingFunction - Determine whether the C++ functions 1687/// Declaration and Definition are "nearly" matching. This heuristic 1688/// is used to improve diagnostics in the case where an out-of-line 1689/// function definition doesn't match any declaration within 1690/// the class or namespace. 1691static bool isNearlyMatchingFunction(ASTContext &Context, 1692 FunctionDecl *Declaration, 1693 FunctionDecl *Definition) { 1694 if (Declaration->param_size() != Definition->param_size()) 1695 return false; 1696 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1697 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1698 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1699 1700 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1701 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1702 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1703 return false; 1704 } 1705 1706 return true; 1707} 1708 1709Sema::DeclPtrTy 1710Sema::HandleDeclarator(Scope *S, Declarator &D, 1711 MultiTemplateParamsArg TemplateParamLists, 1712 bool IsFunctionDefinition) { 1713 DeclarationName Name = GetNameForDeclarator(D); 1714 1715 // All of these full declarators require an identifier. If it doesn't have 1716 // one, the ParsedFreeStandingDeclSpec action should be used. 1717 if (!Name) { 1718 if (!D.isInvalidType()) // Reject this if we think it is valid. 1719 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1720 diag::err_declarator_need_ident) 1721 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1722 return DeclPtrTy(); 1723 } 1724 1725 // The scope passed in may not be a decl scope. Zip up the scope tree until 1726 // we find one that is. 1727 while ((S->getFlags() & Scope::DeclScope) == 0 || 1728 (S->getFlags() & Scope::TemplateParamScope) != 0) 1729 S = S->getParent(); 1730 1731 // If this is an out-of-line definition of a member of a class template 1732 // or class template partial specialization, we may need to rebuild the 1733 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1734 // for more information. 1735 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1736 // handle expressions properly. 1737 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1738 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1739 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1740 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1741 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1742 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1743 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1744 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1745 // FIXME: Preserve type source info. 1746 QualType T = GetTypeFromParser(DS.getTypeRep()); 1747 EnterDeclaratorContext(S, DC); 1748 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1749 ExitDeclaratorContext(S); 1750 if (T.isNull()) 1751 return DeclPtrTy(); 1752 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1753 } 1754 } 1755 1756 DeclContext *DC; 1757 NamedDecl *PrevDecl; 1758 NamedDecl *New; 1759 1760 DeclaratorInfo *DInfo = 0; 1761 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1762 1763 // See if this is a redefinition of a variable in the same scope. 1764 if (D.getCXXScopeSpec().isInvalid()) { 1765 DC = CurContext; 1766 PrevDecl = 0; 1767 D.setInvalidType(); 1768 } else if (!D.getCXXScopeSpec().isSet()) { 1769 LookupNameKind NameKind = LookupOrdinaryName; 1770 1771 // If the declaration we're planning to build will be a function 1772 // or object with linkage, then look for another declaration with 1773 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1774 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1775 /* Do nothing*/; 1776 else if (R->isFunctionType()) { 1777 if (CurContext->isFunctionOrMethod() || 1778 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1779 NameKind = LookupRedeclarationWithLinkage; 1780 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1781 NameKind = LookupRedeclarationWithLinkage; 1782 else if (CurContext->getLookupContext()->isTranslationUnit() && 1783 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1784 NameKind = LookupRedeclarationWithLinkage; 1785 1786 DC = CurContext; 1787 LookupResult R; 1788 LookupName(R, S, Name, NameKind, true, 1789 NameKind == LookupRedeclarationWithLinkage, 1790 D.getIdentifierLoc()); 1791 PrevDecl = R.getAsSingleDecl(Context); 1792 } else { // Something like "int foo::x;" 1793 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1794 1795 if (!DC) { 1796 // If we could not compute the declaration context, it's because the 1797 // declaration context is dependent but does not refer to a class, 1798 // class template, or class template partial specialization. Complain 1799 // and return early, to avoid the coming semantic disaster. 1800 Diag(D.getIdentifierLoc(), 1801 diag::err_template_qualified_declarator_no_match) 1802 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1803 << D.getCXXScopeSpec().getRange(); 1804 return DeclPtrTy(); 1805 } 1806 1807 if (!DC->isDependentContext() && 1808 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1809 return DeclPtrTy(); 1810 1811 LookupResult Res; 1812 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1813 PrevDecl = Res.getAsSingleDecl(Context); 1814 1815 // C++ 7.3.1.2p2: 1816 // Members (including explicit specializations of templates) of a named 1817 // namespace can also be defined outside that namespace by explicit 1818 // qualification of the name being defined, provided that the entity being 1819 // defined was already declared in the namespace and the definition appears 1820 // after the point of declaration in a namespace that encloses the 1821 // declarations namespace. 1822 // 1823 // Note that we only check the context at this point. We don't yet 1824 // have enough information to make sure that PrevDecl is actually 1825 // the declaration we want to match. For example, given: 1826 // 1827 // class X { 1828 // void f(); 1829 // void f(float); 1830 // }; 1831 // 1832 // void X::f(int) { } // ill-formed 1833 // 1834 // In this case, PrevDecl will point to the overload set 1835 // containing the two f's declared in X, but neither of them 1836 // matches. 1837 1838 // First check whether we named the global scope. 1839 if (isa<TranslationUnitDecl>(DC)) { 1840 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1841 << Name << D.getCXXScopeSpec().getRange(); 1842 } else if (!CurContext->Encloses(DC)) { 1843 // The qualifying scope doesn't enclose the original declaration. 1844 // Emit diagnostic based on current scope. 1845 SourceLocation L = D.getIdentifierLoc(); 1846 SourceRange R = D.getCXXScopeSpec().getRange(); 1847 if (isa<FunctionDecl>(CurContext)) 1848 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1849 else 1850 Diag(L, diag::err_invalid_declarator_scope) 1851 << Name << cast<NamedDecl>(DC) << R; 1852 D.setInvalidType(); 1853 } 1854 } 1855 1856 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1857 // Maybe we will complain about the shadowed template parameter. 1858 if (!D.isInvalidType()) 1859 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1860 D.setInvalidType(); 1861 1862 // Just pretend that we didn't see the previous declaration. 1863 PrevDecl = 0; 1864 } 1865 1866 // In C++, the previous declaration we find might be a tag type 1867 // (class or enum). In this case, the new declaration will hide the 1868 // tag type. Note that this does does not apply if we're declaring a 1869 // typedef (C++ [dcl.typedef]p4). 1870 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1871 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1872 PrevDecl = 0; 1873 1874 bool Redeclaration = false; 1875 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1876 if (TemplateParamLists.size()) { 1877 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1878 return DeclPtrTy(); 1879 } 1880 1881 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1882 } else if (R->isFunctionType()) { 1883 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1884 move(TemplateParamLists), 1885 IsFunctionDefinition, Redeclaration); 1886 } else { 1887 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1888 move(TemplateParamLists), 1889 Redeclaration); 1890 } 1891 1892 if (New == 0) 1893 return DeclPtrTy(); 1894 1895 // If this has an identifier and is not an invalid redeclaration or 1896 // function template specialization, add it to the scope stack. 1897 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1898 !(isa<FunctionDecl>(New) && 1899 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1900 PushOnScopeChains(New, S); 1901 1902 return DeclPtrTy::make(New); 1903} 1904 1905/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1906/// types into constant array types in certain situations which would otherwise 1907/// be errors (for GCC compatibility). 1908static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1909 ASTContext &Context, 1910 bool &SizeIsNegative) { 1911 // This method tries to turn a variable array into a constant 1912 // array even when the size isn't an ICE. This is necessary 1913 // for compatibility with code that depends on gcc's buggy 1914 // constant expression folding, like struct {char x[(int)(char*)2];} 1915 SizeIsNegative = false; 1916 1917 QualifierCollector Qs; 1918 const Type *Ty = Qs.strip(T); 1919 1920 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1921 QualType Pointee = PTy->getPointeeType(); 1922 QualType FixedType = 1923 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1924 if (FixedType.isNull()) return FixedType; 1925 FixedType = Context.getPointerType(FixedType); 1926 return Qs.apply(FixedType); 1927 } 1928 1929 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1930 if (!VLATy) 1931 return QualType(); 1932 // FIXME: We should probably handle this case 1933 if (VLATy->getElementType()->isVariablyModifiedType()) 1934 return QualType(); 1935 1936 Expr::EvalResult EvalResult; 1937 if (!VLATy->getSizeExpr() || 1938 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1939 !EvalResult.Val.isInt()) 1940 return QualType(); 1941 1942 llvm::APSInt &Res = EvalResult.Val.getInt(); 1943 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1944 // TODO: preserve the size expression in declarator info 1945 return Context.getConstantArrayType(VLATy->getElementType(), 1946 Res, ArrayType::Normal, 0); 1947 } 1948 1949 SizeIsNegative = true; 1950 return QualType(); 1951} 1952 1953/// \brief Register the given locally-scoped external C declaration so 1954/// that it can be found later for redeclarations 1955void 1956Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1957 Scope *S) { 1958 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1959 "Decl is not a locally-scoped decl!"); 1960 // Note that we have a locally-scoped external with this name. 1961 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1962 1963 if (!PrevDecl) 1964 return; 1965 1966 // If there was a previous declaration of this variable, it may be 1967 // in our identifier chain. Update the identifier chain with the new 1968 // declaration. 1969 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1970 // The previous declaration was found on the identifer resolver 1971 // chain, so remove it from its scope. 1972 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1973 S = S->getParent(); 1974 1975 if (S) 1976 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1977 } 1978} 1979 1980/// \brief Diagnose function specifiers on a declaration of an identifier that 1981/// does not identify a function. 1982void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1983 // FIXME: We should probably indicate the identifier in question to avoid 1984 // confusion for constructs like "inline int a(), b;" 1985 if (D.getDeclSpec().isInlineSpecified()) 1986 Diag(D.getDeclSpec().getInlineSpecLoc(), 1987 diag::err_inline_non_function); 1988 1989 if (D.getDeclSpec().isVirtualSpecified()) 1990 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1991 diag::err_virtual_non_function); 1992 1993 if (D.getDeclSpec().isExplicitSpecified()) 1994 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1995 diag::err_explicit_non_function); 1996} 1997 1998NamedDecl* 1999Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2000 QualType R, DeclaratorInfo *DInfo, 2001 NamedDecl* PrevDecl, bool &Redeclaration) { 2002 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2003 if (D.getCXXScopeSpec().isSet()) { 2004 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2005 << D.getCXXScopeSpec().getRange(); 2006 D.setInvalidType(); 2007 // Pretend we didn't see the scope specifier. 2008 DC = 0; 2009 } 2010 2011 if (getLangOptions().CPlusPlus) { 2012 // Check that there are no default arguments (C++ only). 2013 CheckExtraCXXDefaultArguments(D); 2014 } 2015 2016 DiagnoseFunctionSpecifiers(D); 2017 2018 if (D.getDeclSpec().isThreadSpecified()) 2019 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2020 2021 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2022 if (!NewTD) return 0; 2023 2024 // Handle attributes prior to checking for duplicates in MergeVarDecl 2025 ProcessDeclAttributes(S, NewTD, D); 2026 // Merge the decl with the existing one if appropriate. If the decl is 2027 // in an outer scope, it isn't the same thing. 2028 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2029 Redeclaration = true; 2030 MergeTypeDefDecl(NewTD, PrevDecl); 2031 } 2032 2033 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2034 // then it shall have block scope. 2035 QualType T = NewTD->getUnderlyingType(); 2036 if (T->isVariablyModifiedType()) { 2037 CurFunctionNeedsScopeChecking = true; 2038 2039 if (S->getFnParent() == 0) { 2040 bool SizeIsNegative; 2041 QualType FixedTy = 2042 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2043 if (!FixedTy.isNull()) { 2044 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2045 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2046 } else { 2047 if (SizeIsNegative) 2048 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2049 else if (T->isVariableArrayType()) 2050 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2051 else 2052 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2053 NewTD->setInvalidDecl(); 2054 } 2055 } 2056 } 2057 2058 // If this is the C FILE type, notify the AST context. 2059 if (IdentifierInfo *II = NewTD->getIdentifier()) 2060 if (!NewTD->isInvalidDecl() && 2061 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2062 if (II->isStr("FILE")) 2063 Context.setFILEDecl(NewTD); 2064 else if (II->isStr("jmp_buf")) 2065 Context.setjmp_bufDecl(NewTD); 2066 else if (II->isStr("sigjmp_buf")) 2067 Context.setsigjmp_bufDecl(NewTD); 2068 } 2069 2070 return NewTD; 2071} 2072 2073/// \brief Determines whether the given declaration is an out-of-scope 2074/// previous declaration. 2075/// 2076/// This routine should be invoked when name lookup has found a 2077/// previous declaration (PrevDecl) that is not in the scope where a 2078/// new declaration by the same name is being introduced. If the new 2079/// declaration occurs in a local scope, previous declarations with 2080/// linkage may still be considered previous declarations (C99 2081/// 6.2.2p4-5, C++ [basic.link]p6). 2082/// 2083/// \param PrevDecl the previous declaration found by name 2084/// lookup 2085/// 2086/// \param DC the context in which the new declaration is being 2087/// declared. 2088/// 2089/// \returns true if PrevDecl is an out-of-scope previous declaration 2090/// for a new delcaration with the same name. 2091static bool 2092isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2093 ASTContext &Context) { 2094 if (!PrevDecl) 2095 return 0; 2096 2097 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2098 // case we need to check each of the overloaded functions. 2099 if (!PrevDecl->hasLinkage()) 2100 return false; 2101 2102 if (Context.getLangOptions().CPlusPlus) { 2103 // C++ [basic.link]p6: 2104 // If there is a visible declaration of an entity with linkage 2105 // having the same name and type, ignoring entities declared 2106 // outside the innermost enclosing namespace scope, the block 2107 // scope declaration declares that same entity and receives the 2108 // linkage of the previous declaration. 2109 DeclContext *OuterContext = DC->getLookupContext(); 2110 if (!OuterContext->isFunctionOrMethod()) 2111 // This rule only applies to block-scope declarations. 2112 return false; 2113 else { 2114 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2115 if (PrevOuterContext->isRecord()) 2116 // We found a member function: ignore it. 2117 return false; 2118 else { 2119 // Find the innermost enclosing namespace for the new and 2120 // previous declarations. 2121 while (!OuterContext->isFileContext()) 2122 OuterContext = OuterContext->getParent(); 2123 while (!PrevOuterContext->isFileContext()) 2124 PrevOuterContext = PrevOuterContext->getParent(); 2125 2126 // The previous declaration is in a different namespace, so it 2127 // isn't the same function. 2128 if (OuterContext->getPrimaryContext() != 2129 PrevOuterContext->getPrimaryContext()) 2130 return false; 2131 } 2132 } 2133 } 2134 2135 return true; 2136} 2137 2138NamedDecl* 2139Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2140 QualType R, DeclaratorInfo *DInfo, 2141 NamedDecl* PrevDecl, 2142 MultiTemplateParamsArg TemplateParamLists, 2143 bool &Redeclaration) { 2144 DeclarationName Name = GetNameForDeclarator(D); 2145 2146 // Check that there are no default arguments (C++ only). 2147 if (getLangOptions().CPlusPlus) 2148 CheckExtraCXXDefaultArguments(D); 2149 2150 VarDecl *NewVD; 2151 VarDecl::StorageClass SC; 2152 switch (D.getDeclSpec().getStorageClassSpec()) { 2153 default: assert(0 && "Unknown storage class!"); 2154 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2155 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2156 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2157 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2158 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2159 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2160 case DeclSpec::SCS_mutable: 2161 // mutable can only appear on non-static class members, so it's always 2162 // an error here 2163 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2164 D.setInvalidType(); 2165 SC = VarDecl::None; 2166 break; 2167 } 2168 2169 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2170 if (!II) { 2171 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2172 << Name.getAsString(); 2173 return 0; 2174 } 2175 2176 DiagnoseFunctionSpecifiers(D); 2177 2178 if (!DC->isRecord() && S->getFnParent() == 0) { 2179 // C99 6.9p2: The storage-class specifiers auto and register shall not 2180 // appear in the declaration specifiers in an external declaration. 2181 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2182 2183 // If this is a register variable with an asm label specified, then this 2184 // is a GNU extension. 2185 if (SC == VarDecl::Register && D.getAsmLabel()) 2186 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2187 else 2188 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2189 D.setInvalidType(); 2190 } 2191 } 2192 if (DC->isRecord() && !CurContext->isRecord()) { 2193 // This is an out-of-line definition of a static data member. 2194 if (SC == VarDecl::Static) { 2195 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2196 diag::err_static_out_of_line) 2197 << CodeModificationHint::CreateRemoval( 2198 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2199 } else if (SC == VarDecl::None) 2200 SC = VarDecl::Static; 2201 } 2202 if (SC == VarDecl::Static) { 2203 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2204 if (RD->isLocalClass()) 2205 Diag(D.getIdentifierLoc(), 2206 diag::err_static_data_member_not_allowed_in_local_class) 2207 << Name << RD->getDeclName(); 2208 } 2209 } 2210 2211 // Match up the template parameter lists with the scope specifier, then 2212 // determine whether we have a template or a template specialization. 2213 bool isExplicitSpecialization = false; 2214 if (TemplateParameterList *TemplateParams 2215 = MatchTemplateParametersToScopeSpecifier( 2216 D.getDeclSpec().getSourceRange().getBegin(), 2217 D.getCXXScopeSpec(), 2218 (TemplateParameterList**)TemplateParamLists.get(), 2219 TemplateParamLists.size(), 2220 isExplicitSpecialization)) { 2221 if (TemplateParams->size() > 0) { 2222 // There is no such thing as a variable template. 2223 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2224 << II 2225 << SourceRange(TemplateParams->getTemplateLoc(), 2226 TemplateParams->getRAngleLoc()); 2227 return 0; 2228 } else { 2229 // There is an extraneous 'template<>' for this variable. Complain 2230 // about it, but allow the declaration of the variable. 2231 Diag(TemplateParams->getTemplateLoc(), 2232 diag::err_template_variable_noparams) 2233 << II 2234 << SourceRange(TemplateParams->getTemplateLoc(), 2235 TemplateParams->getRAngleLoc()); 2236 2237 isExplicitSpecialization = true; 2238 } 2239 } 2240 2241 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2242 II, R, DInfo, SC); 2243 2244 if (D.isInvalidType()) 2245 NewVD->setInvalidDecl(); 2246 2247 if (D.getDeclSpec().isThreadSpecified()) { 2248 if (NewVD->hasLocalStorage()) 2249 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2250 else if (!Context.Target.isTLSSupported()) 2251 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2252 else 2253 NewVD->setThreadSpecified(true); 2254 } 2255 2256 // Set the lexical context. If the declarator has a C++ scope specifier, the 2257 // lexical context will be different from the semantic context. 2258 NewVD->setLexicalDeclContext(CurContext); 2259 2260 // Handle attributes prior to checking for duplicates in MergeVarDecl 2261 ProcessDeclAttributes(S, NewVD, D); 2262 2263 // Handle GNU asm-label extension (encoded as an attribute). 2264 if (Expr *E = (Expr*) D.getAsmLabel()) { 2265 // The parser guarantees this is a string. 2266 StringLiteral *SE = cast<StringLiteral>(E); 2267 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2268 SE->getByteLength()))); 2269 } 2270 2271 // If name lookup finds a previous declaration that is not in the 2272 // same scope as the new declaration, this may still be an 2273 // acceptable redeclaration. 2274 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2275 !(NewVD->hasLinkage() && 2276 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2277 PrevDecl = 0; 2278 2279 // Merge the decl with the existing one if appropriate. 2280 if (PrevDecl) { 2281 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2282 // The user tried to define a non-static data member 2283 // out-of-line (C++ [dcl.meaning]p1). 2284 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2285 << D.getCXXScopeSpec().getRange(); 2286 PrevDecl = 0; 2287 NewVD->setInvalidDecl(); 2288 } 2289 } else if (D.getCXXScopeSpec().isSet()) { 2290 // No previous declaration in the qualifying scope. 2291 Diag(D.getIdentifierLoc(), diag::err_no_member) 2292 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2293 << D.getCXXScopeSpec().getRange(); 2294 NewVD->setInvalidDecl(); 2295 } 2296 2297 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2298 2299 // This is an explicit specialization of a static data member. Check it. 2300 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2301 CheckMemberSpecialization(NewVD, PrevDecl)) 2302 NewVD->setInvalidDecl(); 2303 2304 // attributes declared post-definition are currently ignored 2305 if (PrevDecl) { 2306 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2307 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2308 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2309 Diag(Def->getLocation(), diag::note_previous_definition); 2310 } 2311 } 2312 2313 // If this is a locally-scoped extern C variable, update the map of 2314 // such variables. 2315 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2316 !NewVD->isInvalidDecl()) 2317 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2318 2319 return NewVD; 2320} 2321 2322/// \brief Perform semantic checking on a newly-created variable 2323/// declaration. 2324/// 2325/// This routine performs all of the type-checking required for a 2326/// variable declaration once it has been built. It is used both to 2327/// check variables after they have been parsed and their declarators 2328/// have been translated into a declaration, and to check variables 2329/// that have been instantiated from a template. 2330/// 2331/// Sets NewVD->isInvalidDecl() if an error was encountered. 2332void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2333 bool &Redeclaration) { 2334 // If the decl is already known invalid, don't check it. 2335 if (NewVD->isInvalidDecl()) 2336 return; 2337 2338 QualType T = NewVD->getType(); 2339 2340 if (T->isObjCInterfaceType()) { 2341 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2342 return NewVD->setInvalidDecl(); 2343 } 2344 2345 // The variable can not have an abstract class type. 2346 if (RequireNonAbstractType(NewVD->getLocation(), T, 2347 diag::err_abstract_type_in_decl, 2348 AbstractVariableType)) 2349 return NewVD->setInvalidDecl(); 2350 2351 // Emit an error if an address space was applied to decl with local storage. 2352 // This includes arrays of objects with address space qualifiers, but not 2353 // automatic variables that point to other address spaces. 2354 // ISO/IEC TR 18037 S5.1.2 2355 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2356 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2357 return NewVD->setInvalidDecl(); 2358 } 2359 2360 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2361 && !NewVD->hasAttr<BlocksAttr>()) 2362 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2363 2364 bool isVM = T->isVariablyModifiedType(); 2365 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2366 NewVD->hasAttr<BlocksAttr>()) 2367 CurFunctionNeedsScopeChecking = true; 2368 2369 if ((isVM && NewVD->hasLinkage()) || 2370 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2371 bool SizeIsNegative; 2372 QualType FixedTy = 2373 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2374 2375 if (FixedTy.isNull() && T->isVariableArrayType()) { 2376 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2377 // FIXME: This won't give the correct result for 2378 // int a[10][n]; 2379 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2380 2381 if (NewVD->isFileVarDecl()) 2382 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2383 << SizeRange; 2384 else if (NewVD->getStorageClass() == VarDecl::Static) 2385 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2386 << SizeRange; 2387 else 2388 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2389 << SizeRange; 2390 return NewVD->setInvalidDecl(); 2391 } 2392 2393 if (FixedTy.isNull()) { 2394 if (NewVD->isFileVarDecl()) 2395 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2396 else 2397 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2398 return NewVD->setInvalidDecl(); 2399 } 2400 2401 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2402 NewVD->setType(FixedTy); 2403 } 2404 2405 if (!PrevDecl && NewVD->isExternC()) { 2406 // Since we did not find anything by this name and we're declaring 2407 // an extern "C" variable, look for a non-visible extern "C" 2408 // declaration with the same name. 2409 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2410 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2411 if (Pos != LocallyScopedExternalDecls.end()) 2412 PrevDecl = Pos->second; 2413 } 2414 2415 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2416 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2417 << T; 2418 return NewVD->setInvalidDecl(); 2419 } 2420 2421 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2422 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2423 return NewVD->setInvalidDecl(); 2424 } 2425 2426 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2427 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2428 return NewVD->setInvalidDecl(); 2429 } 2430 2431 if (PrevDecl) { 2432 Redeclaration = true; 2433 MergeVarDecl(NewVD, PrevDecl); 2434 } 2435} 2436 2437static bool isUsingDecl(Decl *D) { 2438 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2439} 2440 2441/// \brief Data used with FindOverriddenMethod 2442struct FindOverriddenMethodData { 2443 Sema *S; 2444 CXXMethodDecl *Method; 2445}; 2446 2447/// \brief Member lookup function that determines whether a given C++ 2448/// method overrides a method in a base class, to be used with 2449/// CXXRecordDecl::lookupInBases(). 2450static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2451 CXXBasePath &Path, 2452 void *UserData) { 2453 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2454 2455 FindOverriddenMethodData *Data 2456 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2457 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2458 Path.Decls.first != Path.Decls.second; 2459 ++Path.Decls.first) { 2460 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2461 OverloadedFunctionDecl::function_iterator MatchedDecl; 2462 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2463 return true; 2464 } 2465 } 2466 2467 return false; 2468} 2469 2470NamedDecl* 2471Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2472 QualType R, DeclaratorInfo *DInfo, 2473 NamedDecl* PrevDecl, 2474 MultiTemplateParamsArg TemplateParamLists, 2475 bool IsFunctionDefinition, bool &Redeclaration) { 2476 assert(R.getTypePtr()->isFunctionType()); 2477 2478 DeclarationName Name = GetNameForDeclarator(D); 2479 FunctionDecl::StorageClass SC = FunctionDecl::None; 2480 switch (D.getDeclSpec().getStorageClassSpec()) { 2481 default: assert(0 && "Unknown storage class!"); 2482 case DeclSpec::SCS_auto: 2483 case DeclSpec::SCS_register: 2484 case DeclSpec::SCS_mutable: 2485 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2486 diag::err_typecheck_sclass_func); 2487 D.setInvalidType(); 2488 break; 2489 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2490 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2491 case DeclSpec::SCS_static: { 2492 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2493 // C99 6.7.1p5: 2494 // The declaration of an identifier for a function that has 2495 // block scope shall have no explicit storage-class specifier 2496 // other than extern 2497 // See also (C++ [dcl.stc]p4). 2498 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2499 diag::err_static_block_func); 2500 SC = FunctionDecl::None; 2501 } else 2502 SC = FunctionDecl::Static; 2503 break; 2504 } 2505 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2506 } 2507 2508 if (D.getDeclSpec().isThreadSpecified()) 2509 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2510 2511 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2512 bool isInline = D.getDeclSpec().isInlineSpecified(); 2513 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2514 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2515 2516 // Check that the return type is not an abstract class type. 2517 // For record types, this is done by the AbstractClassUsageDiagnoser once 2518 // the class has been completely parsed. 2519 if (!DC->isRecord() && 2520 RequireNonAbstractType(D.getIdentifierLoc(), 2521 R->getAs<FunctionType>()->getResultType(), 2522 diag::err_abstract_type_in_decl, 2523 AbstractReturnType)) 2524 D.setInvalidType(); 2525 2526 // Do not allow returning a objc interface by-value. 2527 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2528 Diag(D.getIdentifierLoc(), 2529 diag::err_object_cannot_be_passed_returned_by_value) << 0 2530 << R->getAs<FunctionType>()->getResultType(); 2531 D.setInvalidType(); 2532 } 2533 2534 bool isVirtualOkay = false; 2535 FunctionDecl *NewFD; 2536 2537 if (isFriend) { 2538 // DC is the namespace in which the function is being declared. 2539 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2540 "friend function being created in a non-namespace context"); 2541 2542 // C++ [class.friend]p5 2543 // A function can be defined in a friend declaration of a 2544 // class . . . . Such a function is implicitly inline. 2545 isInline |= IsFunctionDefinition; 2546 } 2547 2548 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2549 // This is a C++ constructor declaration. 2550 assert(DC->isRecord() && 2551 "Constructors can only be declared in a member context"); 2552 2553 R = CheckConstructorDeclarator(D, R, SC); 2554 2555 // Create the new declaration 2556 NewFD = CXXConstructorDecl::Create(Context, 2557 cast<CXXRecordDecl>(DC), 2558 D.getIdentifierLoc(), Name, R, DInfo, 2559 isExplicit, isInline, 2560 /*isImplicitlyDeclared=*/false); 2561 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2562 // This is a C++ destructor declaration. 2563 if (DC->isRecord()) { 2564 R = CheckDestructorDeclarator(D, SC); 2565 2566 NewFD = CXXDestructorDecl::Create(Context, 2567 cast<CXXRecordDecl>(DC), 2568 D.getIdentifierLoc(), Name, R, 2569 isInline, 2570 /*isImplicitlyDeclared=*/false); 2571 2572 isVirtualOkay = true; 2573 } else { 2574 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2575 2576 // Create a FunctionDecl to satisfy the function definition parsing 2577 // code path. 2578 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2579 Name, R, DInfo, SC, isInline, 2580 /*hasPrototype=*/true); 2581 D.setInvalidType(); 2582 } 2583 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2584 if (!DC->isRecord()) { 2585 Diag(D.getIdentifierLoc(), 2586 diag::err_conv_function_not_member); 2587 return 0; 2588 } 2589 2590 CheckConversionDeclarator(D, R, SC); 2591 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2592 D.getIdentifierLoc(), Name, R, DInfo, 2593 isInline, isExplicit); 2594 2595 isVirtualOkay = true; 2596 } else if (DC->isRecord()) { 2597 // If the of the function is the same as the name of the record, then this 2598 // must be an invalid constructor that has a return type. 2599 // (The parser checks for a return type and makes the declarator a 2600 // constructor if it has no return type). 2601 // must have an invalid constructor that has a return type 2602 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2603 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2604 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2605 << SourceRange(D.getIdentifierLoc()); 2606 return 0; 2607 } 2608 2609 // This is a C++ method declaration. 2610 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2611 D.getIdentifierLoc(), Name, R, DInfo, 2612 (SC == FunctionDecl::Static), isInline); 2613 2614 isVirtualOkay = (SC != FunctionDecl::Static); 2615 } else { 2616 // Determine whether the function was written with a 2617 // prototype. This true when: 2618 // - we're in C++ (where every function has a prototype), 2619 // - there is a prototype in the declarator, or 2620 // - the type R of the function is some kind of typedef or other reference 2621 // to a type name (which eventually refers to a function type). 2622 bool HasPrototype = 2623 getLangOptions().CPlusPlus || 2624 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2625 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2626 2627 NewFD = FunctionDecl::Create(Context, DC, 2628 D.getIdentifierLoc(), 2629 Name, R, DInfo, SC, isInline, HasPrototype); 2630 } 2631 2632 if (D.isInvalidType()) 2633 NewFD->setInvalidDecl(); 2634 2635 // Set the lexical context. If the declarator has a C++ 2636 // scope specifier, or is the object of a friend declaration, the 2637 // lexical context will be different from the semantic context. 2638 NewFD->setLexicalDeclContext(CurContext); 2639 2640 // Match up the template parameter lists with the scope specifier, then 2641 // determine whether we have a template or a template specialization. 2642 FunctionTemplateDecl *FunctionTemplate = 0; 2643 bool isExplicitSpecialization = false; 2644 bool isFunctionTemplateSpecialization = false; 2645 if (TemplateParameterList *TemplateParams 2646 = MatchTemplateParametersToScopeSpecifier( 2647 D.getDeclSpec().getSourceRange().getBegin(), 2648 D.getCXXScopeSpec(), 2649 (TemplateParameterList**)TemplateParamLists.get(), 2650 TemplateParamLists.size(), 2651 isExplicitSpecialization)) { 2652 if (TemplateParams->size() > 0) { 2653 // This is a function template 2654 2655 // Check that we can declare a template here. 2656 if (CheckTemplateDeclScope(S, TemplateParams)) 2657 return 0; 2658 2659 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2660 NewFD->getLocation(), 2661 Name, TemplateParams, 2662 NewFD); 2663 FunctionTemplate->setLexicalDeclContext(CurContext); 2664 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2665 } else { 2666 // This is a function template specialization. 2667 isFunctionTemplateSpecialization = true; 2668 } 2669 2670 // FIXME: Free this memory properly. 2671 TemplateParamLists.release(); 2672 } 2673 2674 // C++ [dcl.fct.spec]p5: 2675 // The virtual specifier shall only be used in declarations of 2676 // nonstatic class member functions that appear within a 2677 // member-specification of a class declaration; see 10.3. 2678 // 2679 if (isVirtual && !NewFD->isInvalidDecl()) { 2680 if (!isVirtualOkay) { 2681 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2682 diag::err_virtual_non_function); 2683 } else if (!CurContext->isRecord()) { 2684 // 'virtual' was specified outside of the class. 2685 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2686 << CodeModificationHint::CreateRemoval( 2687 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2688 } else { 2689 // Okay: Add virtual to the method. 2690 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2691 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2692 CurClass->setAggregate(false); 2693 CurClass->setPOD(false); 2694 CurClass->setEmpty(false); 2695 CurClass->setPolymorphic(true); 2696 CurClass->setHasTrivialConstructor(false); 2697 CurClass->setHasTrivialCopyConstructor(false); 2698 CurClass->setHasTrivialCopyAssignment(false); 2699 } 2700 } 2701 2702 if (isFriend) { 2703 if (FunctionTemplate) { 2704 FunctionTemplate->setObjectOfFriendDecl( 2705 /* PreviouslyDeclared= */ PrevDecl != NULL); 2706 FunctionTemplate->setAccess(AS_public); 2707 } 2708 else 2709 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2710 2711 NewFD->setAccess(AS_public); 2712 } 2713 2714 2715 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2716 // Look for virtual methods in base classes that this method might override. 2717 CXXBasePaths Paths; 2718 FindOverriddenMethodData Data; 2719 Data.Method = NewMD; 2720 Data.S = this; 2721 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2722 Paths)) { 2723 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2724 E = Paths.found_decls_end(); I != E; ++I) { 2725 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2726 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2727 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2728 NewMD->addOverriddenMethod(OldMD); 2729 } 2730 } 2731 } 2732 } 2733 2734 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2735 !CurContext->isRecord()) { 2736 // C++ [class.static]p1: 2737 // A data or function member of a class may be declared static 2738 // in a class definition, in which case it is a static member of 2739 // the class. 2740 2741 // Complain about the 'static' specifier if it's on an out-of-line 2742 // member function definition. 2743 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2744 diag::err_static_out_of_line) 2745 << CodeModificationHint::CreateRemoval( 2746 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2747 } 2748 2749 // Handle GNU asm-label extension (encoded as an attribute). 2750 if (Expr *E = (Expr*) D.getAsmLabel()) { 2751 // The parser guarantees this is a string. 2752 StringLiteral *SE = cast<StringLiteral>(E); 2753 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2754 SE->getByteLength()))); 2755 } 2756 2757 // Copy the parameter declarations from the declarator D to the function 2758 // declaration NewFD, if they are available. First scavenge them into Params. 2759 llvm::SmallVector<ParmVarDecl*, 16> Params; 2760 if (D.getNumTypeObjects() > 0) { 2761 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2762 2763 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2764 // function that takes no arguments, not a function that takes a 2765 // single void argument. 2766 // We let through "const void" here because Sema::GetTypeForDeclarator 2767 // already checks for that case. 2768 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2769 FTI.ArgInfo[0].Param && 2770 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2771 // Empty arg list, don't push any params. 2772 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2773 2774 // In C++, the empty parameter-type-list must be spelled "void"; a 2775 // typedef of void is not permitted. 2776 if (getLangOptions().CPlusPlus && 2777 Param->getType().getUnqualifiedType() != Context.VoidTy) 2778 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2779 // FIXME: Leaks decl? 2780 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2781 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2782 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2783 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2784 Param->setDeclContext(NewFD); 2785 Params.push_back(Param); 2786 } 2787 } 2788 2789 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2790 // When we're declaring a function with a typedef, typeof, etc as in the 2791 // following example, we'll need to synthesize (unnamed) 2792 // parameters for use in the declaration. 2793 // 2794 // @code 2795 // typedef void fn(int); 2796 // fn f; 2797 // @endcode 2798 2799 // Synthesize a parameter for each argument type. 2800 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2801 AE = FT->arg_type_end(); AI != AE; ++AI) { 2802 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2803 SourceLocation(), 0, 2804 *AI, /*DInfo=*/0, 2805 VarDecl::None, 0); 2806 Param->setImplicit(); 2807 Params.push_back(Param); 2808 } 2809 } else { 2810 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2811 "Should not need args for typedef of non-prototype fn"); 2812 } 2813 // Finally, we know we have the right number of parameters, install them. 2814 NewFD->setParams(Context, Params.data(), Params.size()); 2815 2816 // If name lookup finds a previous declaration that is not in the 2817 // same scope as the new declaration, this may still be an 2818 // acceptable redeclaration. 2819 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2820 !(NewFD->hasLinkage() && 2821 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2822 PrevDecl = 0; 2823 2824 // If the declarator is a template-id, translate the parser's template 2825 // argument list into our AST format. 2826 bool HasExplicitTemplateArgs = false; 2827 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2828 SourceLocation LAngleLoc, RAngleLoc; 2829 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2830 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2831 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2832 TemplateId->getTemplateArgs(), 2833 TemplateId->getTemplateArgIsType(), 2834 TemplateId->NumArgs); 2835 translateTemplateArguments(TemplateArgsPtr, 2836 TemplateId->getTemplateArgLocations(), 2837 TemplateArgs); 2838 TemplateArgsPtr.release(); 2839 2840 HasExplicitTemplateArgs = true; 2841 LAngleLoc = TemplateId->LAngleLoc; 2842 RAngleLoc = TemplateId->RAngleLoc; 2843 2844 if (FunctionTemplate) { 2845 // FIXME: Diagnose function template with explicit template 2846 // arguments. 2847 HasExplicitTemplateArgs = false; 2848 } else if (!isFunctionTemplateSpecialization && 2849 !D.getDeclSpec().isFriendSpecified()) { 2850 // We have encountered something that the user meant to be a 2851 // specialization (because it has explicitly-specified template 2852 // arguments) but that was not introduced with a "template<>" (or had 2853 // too few of them). 2854 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2855 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2856 << CodeModificationHint::CreateInsertion( 2857 D.getDeclSpec().getSourceRange().getBegin(), 2858 "template<> "); 2859 isFunctionTemplateSpecialization = true; 2860 } 2861 } 2862 2863 if (isFunctionTemplateSpecialization) { 2864 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2865 LAngleLoc, TemplateArgs.data(), 2866 TemplateArgs.size(), RAngleLoc, 2867 PrevDecl)) 2868 NewFD->setInvalidDecl(); 2869 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2870 CheckMemberSpecialization(NewFD, PrevDecl)) 2871 NewFD->setInvalidDecl(); 2872 2873 // Perform semantic checking on the function declaration. 2874 bool OverloadableAttrRequired = false; // FIXME: HACK! 2875 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2876 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2877 2878 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2879 // An out-of-line member function declaration must also be a 2880 // definition (C++ [dcl.meaning]p1). 2881 // Note that this is not the case for explicit specializations of 2882 // function templates or member functions of class templates, per 2883 // C++ [temp.expl.spec]p2. 2884 if (!IsFunctionDefinition && !isFriend && 2885 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2886 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2887 << D.getCXXScopeSpec().getRange(); 2888 NewFD->setInvalidDecl(); 2889 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2890 // The user tried to provide an out-of-line definition for a 2891 // function that is a member of a class or namespace, but there 2892 // was no such member function declared (C++ [class.mfct]p2, 2893 // C++ [namespace.memdef]p2). For example: 2894 // 2895 // class X { 2896 // void f() const; 2897 // }; 2898 // 2899 // void X::f() { } // ill-formed 2900 // 2901 // Complain about this problem, and attempt to suggest close 2902 // matches (e.g., those that differ only in cv-qualifiers and 2903 // whether the parameter types are references). 2904 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2905 << Name << DC << D.getCXXScopeSpec().getRange(); 2906 NewFD->setInvalidDecl(); 2907 2908 LookupResult Prev; 2909 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2910 assert(!Prev.isAmbiguous() && 2911 "Cannot have an ambiguity in previous-declaration lookup"); 2912 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2913 Func != FuncEnd; ++Func) { 2914 if (isa<FunctionDecl>(*Func) && 2915 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2916 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2917 } 2918 2919 PrevDecl = 0; 2920 } 2921 } 2922 2923 // Handle attributes. We need to have merged decls when handling attributes 2924 // (for example to check for conflicts, etc). 2925 // FIXME: This needs to happen before we merge declarations. Then, 2926 // let attribute merging cope with attribute conflicts. 2927 ProcessDeclAttributes(S, NewFD, D); 2928 2929 // attributes declared post-definition are currently ignored 2930 if (Redeclaration && PrevDecl) { 2931 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2932 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2933 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2934 Diag(Def->getLocation(), diag::note_previous_definition); 2935 } 2936 } 2937 2938 AddKnownFunctionAttributes(NewFD); 2939 2940 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2941 // If a function name is overloadable in C, then every function 2942 // with that name must be marked "overloadable". 2943 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2944 << Redeclaration << NewFD; 2945 if (PrevDecl) 2946 Diag(PrevDecl->getLocation(), 2947 diag::note_attribute_overloadable_prev_overload); 2948 NewFD->addAttr(::new (Context) OverloadableAttr()); 2949 } 2950 2951 // If this is a locally-scoped extern C function, update the 2952 // map of such names. 2953 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2954 && !NewFD->isInvalidDecl()) 2955 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2956 2957 // Set this FunctionDecl's range up to the right paren. 2958 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2959 2960 if (FunctionTemplate && NewFD->isInvalidDecl()) 2961 FunctionTemplate->setInvalidDecl(); 2962 2963 if (FunctionTemplate) 2964 return FunctionTemplate; 2965 2966 return NewFD; 2967} 2968 2969/// \brief Perform semantic checking of a new function declaration. 2970/// 2971/// Performs semantic analysis of the new function declaration 2972/// NewFD. This routine performs all semantic checking that does not 2973/// require the actual declarator involved in the declaration, and is 2974/// used both for the declaration of functions as they are parsed 2975/// (called via ActOnDeclarator) and for the declaration of functions 2976/// that have been instantiated via C++ template instantiation (called 2977/// via InstantiateDecl). 2978/// 2979/// \param IsExplicitSpecialiation whether this new function declaration is 2980/// an explicit specialization of the previous declaration. 2981/// 2982/// This sets NewFD->isInvalidDecl() to true if there was an error. 2983void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2984 bool IsExplicitSpecialization, 2985 bool &Redeclaration, 2986 bool &OverloadableAttrRequired) { 2987 // If NewFD is already known erroneous, don't do any of this checking. 2988 if (NewFD->isInvalidDecl()) 2989 return; 2990 2991 if (NewFD->getResultType()->isVariablyModifiedType()) { 2992 // Functions returning a variably modified type violate C99 6.7.5.2p2 2993 // because all functions have linkage. 2994 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2995 return NewFD->setInvalidDecl(); 2996 } 2997 2998 if (NewFD->isMain()) 2999 CheckMain(NewFD); 3000 3001 // Check for a previous declaration of this name. 3002 if (!PrevDecl && NewFD->isExternC()) { 3003 // Since we did not find anything by this name and we're declaring 3004 // an extern "C" function, look for a non-visible extern "C" 3005 // declaration with the same name. 3006 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3007 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3008 if (Pos != LocallyScopedExternalDecls.end()) 3009 PrevDecl = Pos->second; 3010 } 3011 3012 // Merge or overload the declaration with an existing declaration of 3013 // the same name, if appropriate. 3014 if (PrevDecl) { 3015 // Determine whether NewFD is an overload of PrevDecl or 3016 // a declaration that requires merging. If it's an overload, 3017 // there's no more work to do here; we'll just add the new 3018 // function to the scope. 3019 OverloadedFunctionDecl::function_iterator MatchedDecl; 3020 3021 if (!getLangOptions().CPlusPlus && 3022 AllowOverloadingOfFunction(PrevDecl, Context)) { 3023 OverloadableAttrRequired = true; 3024 3025 // Functions marked "overloadable" must have a prototype (that 3026 // we can't get through declaration merging). 3027 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3028 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3029 << NewFD; 3030 Redeclaration = true; 3031 3032 // Turn this into a variadic function with no parameters. 3033 QualType R = Context.getFunctionType( 3034 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3035 0, 0, true, 0); 3036 NewFD->setType(R); 3037 return NewFD->setInvalidDecl(); 3038 } 3039 } 3040 3041 if (PrevDecl && 3042 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3043 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3044 Redeclaration = true; 3045 Decl *OldDecl = PrevDecl; 3046 3047 // If PrevDecl was an overloaded function, extract the 3048 // FunctionDecl that matched. 3049 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3050 OldDecl = *MatchedDecl; 3051 3052 // NewFD and OldDecl represent declarations that need to be 3053 // merged. 3054 if (MergeFunctionDecl(NewFD, OldDecl)) 3055 return NewFD->setInvalidDecl(); 3056 3057 if (FunctionTemplateDecl *OldTemplateDecl 3058 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3059 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3060 FunctionTemplateDecl *NewTemplateDecl 3061 = NewFD->getDescribedFunctionTemplate(); 3062 assert(NewTemplateDecl && "Template/non-template mismatch"); 3063 if (CXXMethodDecl *Method 3064 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3065 Method->setAccess(OldTemplateDecl->getAccess()); 3066 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3067 } 3068 3069 // If this is an explicit specialization of a member that is a function 3070 // template, mark it as a member specialization. 3071 if (IsExplicitSpecialization && 3072 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3073 NewTemplateDecl->setMemberSpecialization(); 3074 assert(OldTemplateDecl->isMemberSpecialization()); 3075 } 3076 } else { 3077 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3078 NewFD->setAccess(OldDecl->getAccess()); 3079 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3080 } 3081 } 3082 } 3083 3084 // Semantic checking for this function declaration (in isolation). 3085 if (getLangOptions().CPlusPlus) { 3086 // C++-specific checks. 3087 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3088 CheckConstructor(Constructor); 3089 } else if (isa<CXXDestructorDecl>(NewFD)) { 3090 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3091 QualType ClassType = Context.getTypeDeclType(Record); 3092 if (!ClassType->isDependentType()) { 3093 DeclarationName Name 3094 = Context.DeclarationNames.getCXXDestructorName( 3095 Context.getCanonicalType(ClassType)); 3096 if (NewFD->getDeclName() != Name) { 3097 Diag(NewFD->getLocation(), diag::err_destructor_name); 3098 return NewFD->setInvalidDecl(); 3099 } 3100 } 3101 Record->setUserDeclaredDestructor(true); 3102 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3103 // user-defined destructor. 3104 Record->setPOD(false); 3105 3106 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3107 // declared destructor. 3108 // FIXME: C++0x: don't do this for "= default" destructors 3109 Record->setHasTrivialDestructor(false); 3110 } else if (CXXConversionDecl *Conversion 3111 = dyn_cast<CXXConversionDecl>(NewFD)) 3112 ActOnConversionDeclarator(Conversion); 3113 3114 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3115 if (NewFD->isOverloadedOperator() && 3116 CheckOverloadedOperatorDeclaration(NewFD)) 3117 return NewFD->setInvalidDecl(); 3118 3119 // In C++, check default arguments now that we have merged decls. Unless 3120 // the lexical context is the class, because in this case this is done 3121 // during delayed parsing anyway. 3122 if (!CurContext->isRecord()) 3123 CheckCXXDefaultArguments(NewFD); 3124 } 3125} 3126 3127void Sema::CheckMain(FunctionDecl* FD) { 3128 // C++ [basic.start.main]p3: A program that declares main to be inline 3129 // or static is ill-formed. 3130 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3131 // shall not appear in a declaration of main. 3132 // static main is not an error under C99, but we should warn about it. 3133 bool isInline = FD->isInlineSpecified(); 3134 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3135 if (isInline || isStatic) { 3136 unsigned diagID = diag::warn_unusual_main_decl; 3137 if (isInline || getLangOptions().CPlusPlus) 3138 diagID = diag::err_unusual_main_decl; 3139 3140 int which = isStatic + (isInline << 1) - 1; 3141 Diag(FD->getLocation(), diagID) << which; 3142 } 3143 3144 QualType T = FD->getType(); 3145 assert(T->isFunctionType() && "function decl is not of function type"); 3146 const FunctionType* FT = T->getAs<FunctionType>(); 3147 3148 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3149 // TODO: add a replacement fixit to turn the return type into 'int'. 3150 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3151 FD->setInvalidDecl(true); 3152 } 3153 3154 // Treat protoless main() as nullary. 3155 if (isa<FunctionNoProtoType>(FT)) return; 3156 3157 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3158 unsigned nparams = FTP->getNumArgs(); 3159 assert(FD->getNumParams() == nparams); 3160 3161 if (nparams > 3) { 3162 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3163 FD->setInvalidDecl(true); 3164 nparams = 3; 3165 } 3166 3167 // FIXME: a lot of the following diagnostics would be improved 3168 // if we had some location information about types. 3169 3170 QualType CharPP = 3171 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3172 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3173 3174 for (unsigned i = 0; i < nparams; ++i) { 3175 QualType AT = FTP->getArgType(i); 3176 3177 bool mismatch = true; 3178 3179 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3180 mismatch = false; 3181 else if (Expected[i] == CharPP) { 3182 // As an extension, the following forms are okay: 3183 // char const ** 3184 // char const * const * 3185 // char * const * 3186 3187 QualifierCollector qs; 3188 const PointerType* PT; 3189 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3190 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3191 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3192 qs.removeConst(); 3193 mismatch = !qs.empty(); 3194 } 3195 } 3196 3197 if (mismatch) { 3198 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3199 // TODO: suggest replacing given type with expected type 3200 FD->setInvalidDecl(true); 3201 } 3202 } 3203 3204 if (nparams == 1 && !FD->isInvalidDecl()) { 3205 Diag(FD->getLocation(), diag::warn_main_one_arg); 3206 } 3207} 3208 3209bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3210 // FIXME: Need strict checking. In C89, we need to check for 3211 // any assignment, increment, decrement, function-calls, or 3212 // commas outside of a sizeof. In C99, it's the same list, 3213 // except that the aforementioned are allowed in unevaluated 3214 // expressions. Everything else falls under the 3215 // "may accept other forms of constant expressions" exception. 3216 // (We never end up here for C++, so the constant expression 3217 // rules there don't matter.) 3218 if (Init->isConstantInitializer(Context)) 3219 return false; 3220 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3221 << Init->getSourceRange(); 3222 return true; 3223} 3224 3225void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3226 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3227} 3228 3229/// AddInitializerToDecl - Adds the initializer Init to the 3230/// declaration dcl. If DirectInit is true, this is C++ direct 3231/// initialization rather than copy initialization. 3232void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3233 Decl *RealDecl = dcl.getAs<Decl>(); 3234 // If there is no declaration, there was an error parsing it. Just ignore 3235 // the initializer. 3236 if (RealDecl == 0) 3237 return; 3238 3239 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3240 // With declarators parsed the way they are, the parser cannot 3241 // distinguish between a normal initializer and a pure-specifier. 3242 // Thus this grotesque test. 3243 IntegerLiteral *IL; 3244 Expr *Init = static_cast<Expr *>(init.get()); 3245 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3246 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3247 if (Method->isVirtualAsWritten()) { 3248 Method->setPure(); 3249 3250 // A class is abstract if at least one function is pure virtual. 3251 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3252 } else if (!Method->isInvalidDecl()) { 3253 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3254 << Method->getDeclName() << Init->getSourceRange(); 3255 Method->setInvalidDecl(); 3256 } 3257 } else { 3258 Diag(Method->getLocation(), diag::err_member_function_initialization) 3259 << Method->getDeclName() << Init->getSourceRange(); 3260 Method->setInvalidDecl(); 3261 } 3262 return; 3263 } 3264 3265 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3266 if (!VDecl) { 3267 if (getLangOptions().CPlusPlus && 3268 RealDecl->getLexicalDeclContext()->isRecord() && 3269 isa<NamedDecl>(RealDecl)) 3270 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3271 << cast<NamedDecl>(RealDecl)->getDeclName(); 3272 else 3273 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3274 RealDecl->setInvalidDecl(); 3275 return; 3276 } 3277 3278 if (!VDecl->getType()->isArrayType() && 3279 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3280 diag::err_typecheck_decl_incomplete_type)) { 3281 RealDecl->setInvalidDecl(); 3282 return; 3283 } 3284 3285 const VarDecl *Def = 0; 3286 if (VDecl->getDefinition(Def)) { 3287 Diag(VDecl->getLocation(), diag::err_redefinition) 3288 << VDecl->getDeclName(); 3289 Diag(Def->getLocation(), diag::note_previous_definition); 3290 VDecl->setInvalidDecl(); 3291 return; 3292 } 3293 3294 // Take ownership of the expression, now that we're sure we have somewhere 3295 // to put it. 3296 Expr *Init = init.takeAs<Expr>(); 3297 assert(Init && "missing initializer"); 3298 3299 // Get the decls type and save a reference for later, since 3300 // CheckInitializerTypes may change it. 3301 QualType DclT = VDecl->getType(), SavT = DclT; 3302 if (VDecl->isBlockVarDecl()) { 3303 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3304 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3305 VDecl->setInvalidDecl(); 3306 } else if (!VDecl->isInvalidDecl()) { 3307 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3308 VDecl->getDeclName(), DirectInit)) 3309 VDecl->setInvalidDecl(); 3310 3311 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3312 // Don't check invalid declarations to avoid emitting useless diagnostics. 3313 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3314 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3315 CheckForConstantInitializer(Init, DclT); 3316 } 3317 } 3318 } else if (VDecl->isStaticDataMember() && 3319 VDecl->getLexicalDeclContext()->isRecord()) { 3320 // This is an in-class initialization for a static data member, e.g., 3321 // 3322 // struct S { 3323 // static const int value = 17; 3324 // }; 3325 3326 // Attach the initializer 3327 VDecl->setInit(Context, Init); 3328 3329 // C++ [class.mem]p4: 3330 // A member-declarator can contain a constant-initializer only 3331 // if it declares a static member (9.4) of const integral or 3332 // const enumeration type, see 9.4.2. 3333 QualType T = VDecl->getType(); 3334 if (!T->isDependentType() && 3335 (!Context.getCanonicalType(T).isConstQualified() || 3336 !T->isIntegralType())) { 3337 Diag(VDecl->getLocation(), diag::err_member_initialization) 3338 << VDecl->getDeclName() << Init->getSourceRange(); 3339 VDecl->setInvalidDecl(); 3340 } else { 3341 // C++ [class.static.data]p4: 3342 // If a static data member is of const integral or const 3343 // enumeration type, its declaration in the class definition 3344 // can specify a constant-initializer which shall be an 3345 // integral constant expression (5.19). 3346 if (!Init->isTypeDependent() && 3347 !Init->getType()->isIntegralType()) { 3348 // We have a non-dependent, non-integral or enumeration type. 3349 Diag(Init->getSourceRange().getBegin(), 3350 diag::err_in_class_initializer_non_integral_type) 3351 << Init->getType() << Init->getSourceRange(); 3352 VDecl->setInvalidDecl(); 3353 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3354 // Check whether the expression is a constant expression. 3355 llvm::APSInt Value; 3356 SourceLocation Loc; 3357 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3358 Diag(Loc, diag::err_in_class_initializer_non_constant) 3359 << Init->getSourceRange(); 3360 VDecl->setInvalidDecl(); 3361 } else if (!VDecl->getType()->isDependentType()) 3362 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3363 } 3364 } 3365 } else if (VDecl->isFileVarDecl()) { 3366 if (VDecl->getStorageClass() == VarDecl::Extern) 3367 Diag(VDecl->getLocation(), diag::warn_extern_init); 3368 if (!VDecl->isInvalidDecl()) 3369 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3370 VDecl->getDeclName(), DirectInit)) 3371 VDecl->setInvalidDecl(); 3372 3373 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3374 // Don't check invalid declarations to avoid emitting useless diagnostics. 3375 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3376 // C99 6.7.8p4. All file scoped initializers need to be constant. 3377 CheckForConstantInitializer(Init, DclT); 3378 } 3379 } 3380 // If the type changed, it means we had an incomplete type that was 3381 // completed by the initializer. For example: 3382 // int ary[] = { 1, 3, 5 }; 3383 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3384 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3385 VDecl->setType(DclT); 3386 Init->setType(DclT); 3387 } 3388 3389 Init = MaybeCreateCXXExprWithTemporaries(Init, 3390 /*ShouldDestroyTemporaries=*/true); 3391 // Attach the initializer to the decl. 3392 VDecl->setInit(Context, Init); 3393 3394 // If the previous declaration of VDecl was a tentative definition, 3395 // remove it from the set of tentative definitions. 3396 if (VDecl->getPreviousDeclaration() && 3397 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3398 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3399 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3400 } 3401 3402 return; 3403} 3404 3405void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3406 bool TypeContainsUndeducedAuto) { 3407 Decl *RealDecl = dcl.getAs<Decl>(); 3408 3409 // If there is no declaration, there was an error parsing it. Just ignore it. 3410 if (RealDecl == 0) 3411 return; 3412 3413 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3414 QualType Type = Var->getType(); 3415 3416 // Record tentative definitions. 3417 if (Var->isTentativeDefinition(Context)) { 3418 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3419 InsertPair = 3420 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3421 3422 // Keep the latest definition in the map. If we see 'int i; int i;' we 3423 // want the second one in the map. 3424 InsertPair.first->second = Var; 3425 3426 // However, for the list, we don't care about the order, just make sure 3427 // that there are no dupes for a given declaration name. 3428 if (InsertPair.second) 3429 TentativeDefinitionList.push_back(Var->getDeclName()); 3430 } 3431 3432 // C++ [dcl.init.ref]p3: 3433 // The initializer can be omitted for a reference only in a 3434 // parameter declaration (8.3.5), in the declaration of a 3435 // function return type, in the declaration of a class member 3436 // within its class declaration (9.2), and where the extern 3437 // specifier is explicitly used. 3438 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3439 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3440 << Var->getDeclName() 3441 << SourceRange(Var->getLocation(), Var->getLocation()); 3442 Var->setInvalidDecl(); 3443 return; 3444 } 3445 3446 // C++0x [dcl.spec.auto]p3 3447 if (TypeContainsUndeducedAuto) { 3448 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3449 << Var->getDeclName() << Type; 3450 Var->setInvalidDecl(); 3451 return; 3452 } 3453 3454 // An array without size is an incomplete type, and there are no special 3455 // rules in C++ to make such a definition acceptable. 3456 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3457 !Var->hasExternalStorage()) { 3458 Diag(Var->getLocation(), 3459 diag::err_typecheck_incomplete_array_needs_initializer); 3460 Var->setInvalidDecl(); 3461 return; 3462 } 3463 3464 // C++ [temp.expl.spec]p15: 3465 // An explicit specialization of a static data member of a template is a 3466 // definition if the declaration includes an initializer; otherwise, it 3467 // is a declaration. 3468 if (Var->isStaticDataMember() && 3469 Var->getInstantiatedFromStaticDataMember() && 3470 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3471 return; 3472 3473 // C++ [dcl.init]p9: 3474 // If no initializer is specified for an object, and the object 3475 // is of (possibly cv-qualified) non-POD class type (or array 3476 // thereof), the object shall be default-initialized; if the 3477 // object is of const-qualified type, the underlying class type 3478 // shall have a user-declared default constructor. 3479 // 3480 // FIXME: Diagnose the "user-declared default constructor" bit. 3481 if (getLangOptions().CPlusPlus) { 3482 QualType InitType = Type; 3483 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3484 InitType = Context.getBaseElementType(Array); 3485 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3486 InitType->isRecordType() && !InitType->isDependentType()) { 3487 if (!RequireCompleteType(Var->getLocation(), InitType, 3488 diag::err_invalid_incomplete_type_use)) { 3489 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3490 3491 CXXConstructorDecl *Constructor 3492 = PerformInitializationByConstructor(InitType, 3493 MultiExprArg(*this, 0, 0), 3494 Var->getLocation(), 3495 SourceRange(Var->getLocation(), 3496 Var->getLocation()), 3497 Var->getDeclName(), 3498 IK_Default, 3499 ConstructorArgs); 3500 3501 // FIXME: Location info for the variable initialization? 3502 if (!Constructor) 3503 Var->setInvalidDecl(); 3504 else { 3505 // FIXME: Cope with initialization of arrays 3506 if (!Constructor->isTrivial() && 3507 InitializeVarWithConstructor(Var, Constructor, 3508 move_arg(ConstructorArgs))) 3509 Var->setInvalidDecl(); 3510 3511 FinalizeVarWithDestructor(Var, InitType); 3512 } 3513 } else { 3514 Var->setInvalidDecl(); 3515 } 3516 } 3517 } 3518 3519#if 0 3520 // FIXME: Temporarily disabled because we are not properly parsing 3521 // linkage specifications on declarations, e.g., 3522 // 3523 // extern "C" const CGPoint CGPointerZero; 3524 // 3525 // C++ [dcl.init]p9: 3526 // 3527 // If no initializer is specified for an object, and the 3528 // object is of (possibly cv-qualified) non-POD class type (or 3529 // array thereof), the object shall be default-initialized; if 3530 // the object is of const-qualified type, the underlying class 3531 // type shall have a user-declared default 3532 // constructor. Otherwise, if no initializer is specified for 3533 // an object, the object and its subobjects, if any, have an 3534 // indeterminate initial value; if the object or any of its 3535 // subobjects are of const-qualified type, the program is 3536 // ill-formed. 3537 // 3538 // This isn't technically an error in C, so we don't diagnose it. 3539 // 3540 // FIXME: Actually perform the POD/user-defined default 3541 // constructor check. 3542 if (getLangOptions().CPlusPlus && 3543 Context.getCanonicalType(Type).isConstQualified() && 3544 !Var->hasExternalStorage()) 3545 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3546 << Var->getName() 3547 << SourceRange(Var->getLocation(), Var->getLocation()); 3548#endif 3549 } 3550} 3551 3552Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3553 DeclPtrTy *Group, 3554 unsigned NumDecls) { 3555 llvm::SmallVector<Decl*, 8> Decls; 3556 3557 if (DS.isTypeSpecOwned()) 3558 Decls.push_back((Decl*)DS.getTypeRep()); 3559 3560 for (unsigned i = 0; i != NumDecls; ++i) 3561 if (Decl *D = Group[i].getAs<Decl>()) 3562 Decls.push_back(D); 3563 3564 // Perform semantic analysis that depends on having fully processed both 3565 // the declarator and initializer. 3566 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3567 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3568 if (!IDecl) 3569 continue; 3570 QualType T = IDecl->getType(); 3571 3572 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3573 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3574 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3575 if (T->isDependentType()) { 3576 // If T is dependent, we should not require a complete type. 3577 // (RequireCompleteType shouldn't be called with dependent types.) 3578 // But we still can at least check if we've got an array of unspecified 3579 // size without an initializer. 3580 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3581 !IDecl->getInit()) { 3582 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3583 << T; 3584 IDecl->setInvalidDecl(); 3585 } 3586 } else if (!IDecl->isInvalidDecl()) { 3587 // If T is an incomplete array type with an initializer list that is 3588 // dependent on something, its size has not been fixed. We could attempt 3589 // to fix the size for such arrays, but we would still have to check 3590 // here for initializers containing a C++0x vararg expansion, e.g. 3591 // template <typename... Args> void f(Args... args) { 3592 // int vals[] = { args }; 3593 // } 3594 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3595 Expr *Init = IDecl->getInit(); 3596 if (IAT && Init && 3597 (Init->isTypeDependent() || Init->isValueDependent())) { 3598 // Check that the member type of the array is complete, at least. 3599 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3600 diag::err_typecheck_decl_incomplete_type)) 3601 IDecl->setInvalidDecl(); 3602 } else if (RequireCompleteType(IDecl->getLocation(), T, 3603 diag::err_typecheck_decl_incomplete_type)) 3604 IDecl->setInvalidDecl(); 3605 } 3606 } 3607 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3608 // object that has file scope without an initializer, and without a 3609 // storage-class specifier or with the storage-class specifier "static", 3610 // constitutes a tentative definition. Note: A tentative definition with 3611 // external linkage is valid (C99 6.2.2p5). 3612 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3613 if (const IncompleteArrayType *ArrayT 3614 = Context.getAsIncompleteArrayType(T)) { 3615 if (RequireCompleteType(IDecl->getLocation(), 3616 ArrayT->getElementType(), 3617 diag::err_illegal_decl_array_incomplete_type)) 3618 IDecl->setInvalidDecl(); 3619 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3620 // C99 6.9.2p3: If the declaration of an identifier for an object is 3621 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3622 // declared type shall not be an incomplete type. 3623 // NOTE: code such as the following 3624 // static struct s; 3625 // struct s { int a; }; 3626 // is accepted by gcc. Hence here we issue a warning instead of 3627 // an error and we do not invalidate the static declaration. 3628 // NOTE: to avoid multiple warnings, only check the first declaration. 3629 if (IDecl->getPreviousDeclaration() == 0) 3630 RequireCompleteType(IDecl->getLocation(), T, 3631 diag::ext_typecheck_decl_incomplete_type); 3632 } 3633 } 3634 } 3635 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3636 Decls.data(), Decls.size())); 3637} 3638 3639 3640/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3641/// to introduce parameters into function prototype scope. 3642Sema::DeclPtrTy 3643Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3644 const DeclSpec &DS = D.getDeclSpec(); 3645 3646 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3647 VarDecl::StorageClass StorageClass = VarDecl::None; 3648 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3649 StorageClass = VarDecl::Register; 3650 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3651 Diag(DS.getStorageClassSpecLoc(), 3652 diag::err_invalid_storage_class_in_func_decl); 3653 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3654 } 3655 3656 if (D.getDeclSpec().isThreadSpecified()) 3657 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3658 3659 DiagnoseFunctionSpecifiers(D); 3660 3661 // Check that there are no default arguments inside the type of this 3662 // parameter (C++ only). 3663 if (getLangOptions().CPlusPlus) 3664 CheckExtraCXXDefaultArguments(D); 3665 3666 DeclaratorInfo *DInfo = 0; 3667 TagDecl *OwnedDecl = 0; 3668 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3669 3670 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3671 // C++ [dcl.fct]p6: 3672 // Types shall not be defined in return or parameter types. 3673 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3674 << Context.getTypeDeclType(OwnedDecl); 3675 } 3676 3677 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3678 // Can this happen for params? We already checked that they don't conflict 3679 // among each other. Here they can only shadow globals, which is ok. 3680 IdentifierInfo *II = D.getIdentifier(); 3681 if (II) { 3682 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3683 if (PrevDecl->isTemplateParameter()) { 3684 // Maybe we will complain about the shadowed template parameter. 3685 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3686 // Just pretend that we didn't see the previous declaration. 3687 PrevDecl = 0; 3688 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3689 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3690 3691 // Recover by removing the name 3692 II = 0; 3693 D.SetIdentifier(0, D.getIdentifierLoc()); 3694 } 3695 } 3696 } 3697 3698 // Parameters can not be abstract class types. 3699 // For record types, this is done by the AbstractClassUsageDiagnoser once 3700 // the class has been completely parsed. 3701 if (!CurContext->isRecord() && 3702 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3703 diag::err_abstract_type_in_decl, 3704 AbstractParamType)) 3705 D.setInvalidType(true); 3706 3707 QualType T = adjustParameterType(parmDeclType); 3708 3709 ParmVarDecl *New 3710 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3711 T, DInfo, StorageClass, 0); 3712 3713 if (D.isInvalidType()) 3714 New->setInvalidDecl(); 3715 3716 // Parameter declarators cannot be interface types. All ObjC objects are 3717 // passed by reference. 3718 if (T->isObjCInterfaceType()) { 3719 Diag(D.getIdentifierLoc(), 3720 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3721 New->setInvalidDecl(); 3722 } 3723 3724 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3725 if (D.getCXXScopeSpec().isSet()) { 3726 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3727 << D.getCXXScopeSpec().getRange(); 3728 New->setInvalidDecl(); 3729 } 3730 3731 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3732 // duration shall not be qualified by an address-space qualifier." 3733 // Since all parameters have automatic store duration, they can not have 3734 // an address space. 3735 if (T.getAddressSpace() != 0) { 3736 Diag(D.getIdentifierLoc(), 3737 diag::err_arg_with_address_space); 3738 New->setInvalidDecl(); 3739 } 3740 3741 3742 // Add the parameter declaration into this scope. 3743 S->AddDecl(DeclPtrTy::make(New)); 3744 if (II) 3745 IdResolver.AddDecl(New); 3746 3747 ProcessDeclAttributes(S, New, D); 3748 3749 if (New->hasAttr<BlocksAttr>()) { 3750 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3751 } 3752 return DeclPtrTy::make(New); 3753} 3754 3755void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3756 SourceLocation LocAfterDecls) { 3757 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3758 "Not a function declarator!"); 3759 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3760 3761 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3762 // for a K&R function. 3763 if (!FTI.hasPrototype) { 3764 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3765 --i; 3766 if (FTI.ArgInfo[i].Param == 0) { 3767 llvm::SmallString<256> Code; 3768 llvm::raw_svector_ostream(Code) << " int " 3769 << FTI.ArgInfo[i].Ident->getName() 3770 << ";\n"; 3771 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3772 << FTI.ArgInfo[i].Ident 3773 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3774 3775 // Implicitly declare the argument as type 'int' for lack of a better 3776 // type. 3777 DeclSpec DS; 3778 const char* PrevSpec; // unused 3779 unsigned DiagID; // unused 3780 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3781 PrevSpec, DiagID); 3782 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3783 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3784 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3785 } 3786 } 3787 } 3788} 3789 3790Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3791 Declarator &D) { 3792 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3793 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3794 "Not a function declarator!"); 3795 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3796 3797 if (FTI.hasPrototype) { 3798 // FIXME: Diagnose arguments without names in C. 3799 } 3800 3801 Scope *ParentScope = FnBodyScope->getParent(); 3802 3803 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3804 MultiTemplateParamsArg(*this), 3805 /*IsFunctionDefinition=*/true); 3806 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3807} 3808 3809Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3810 // Clear the last template instantiation error context. 3811 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3812 3813 if (!D) 3814 return D; 3815 FunctionDecl *FD = 0; 3816 3817 if (FunctionTemplateDecl *FunTmpl 3818 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3819 FD = FunTmpl->getTemplatedDecl(); 3820 else 3821 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3822 3823 CurFunctionNeedsScopeChecking = false; 3824 3825 // See if this is a redefinition. 3826 const FunctionDecl *Definition; 3827 if (FD->getBody(Definition)) { 3828 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3829 Diag(Definition->getLocation(), diag::note_previous_definition); 3830 } 3831 3832 // Builtin functions cannot be defined. 3833 if (unsigned BuiltinID = FD->getBuiltinID()) { 3834 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3835 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3836 FD->setInvalidDecl(); 3837 } 3838 } 3839 3840 // The return type of a function definition must be complete 3841 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3842 QualType ResultType = FD->getResultType(); 3843 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3844 !FD->isInvalidDecl() && 3845 RequireCompleteType(FD->getLocation(), ResultType, 3846 diag::err_func_def_incomplete_result)) 3847 FD->setInvalidDecl(); 3848 3849 // GNU warning -Wmissing-prototypes: 3850 // Warn if a global function is defined without a previous 3851 // prototype declaration. This warning is issued even if the 3852 // definition itself provides a prototype. The aim is to detect 3853 // global functions that fail to be declared in header files. 3854 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3855 !FD->isMain()) { 3856 bool MissingPrototype = true; 3857 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3858 Prev; Prev = Prev->getPreviousDeclaration()) { 3859 // Ignore any declarations that occur in function or method 3860 // scope, because they aren't visible from the header. 3861 if (Prev->getDeclContext()->isFunctionOrMethod()) 3862 continue; 3863 3864 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3865 break; 3866 } 3867 3868 if (MissingPrototype) 3869 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3870 } 3871 3872 if (FnBodyScope) 3873 PushDeclContext(FnBodyScope, FD); 3874 3875 // Check the validity of our function parameters 3876 CheckParmsForFunctionDef(FD); 3877 3878 // Introduce our parameters into the function scope 3879 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3880 ParmVarDecl *Param = FD->getParamDecl(p); 3881 Param->setOwningFunction(FD); 3882 3883 // If this has an identifier, add it to the scope stack. 3884 if (Param->getIdentifier() && FnBodyScope) 3885 PushOnScopeChains(Param, FnBodyScope); 3886 } 3887 3888 // Checking attributes of current function definition 3889 // dllimport attribute. 3890 if (FD->getAttr<DLLImportAttr>() && 3891 (!FD->getAttr<DLLExportAttr>())) { 3892 // dllimport attribute cannot be applied to definition. 3893 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3894 Diag(FD->getLocation(), 3895 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3896 << "dllimport"; 3897 FD->setInvalidDecl(); 3898 return DeclPtrTy::make(FD); 3899 } else { 3900 // If a symbol previously declared dllimport is later defined, the 3901 // attribute is ignored in subsequent references, and a warning is 3902 // emitted. 3903 Diag(FD->getLocation(), 3904 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3905 << FD->getNameAsCString() << "dllimport"; 3906 } 3907 } 3908 return DeclPtrTy::make(FD); 3909} 3910 3911Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3912 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3913} 3914 3915Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3916 bool IsInstantiation) { 3917 Decl *dcl = D.getAs<Decl>(); 3918 Stmt *Body = BodyArg.takeAs<Stmt>(); 3919 3920 FunctionDecl *FD = 0; 3921 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3922 if (FunTmpl) 3923 FD = FunTmpl->getTemplatedDecl(); 3924 else 3925 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3926 3927 if (FD) { 3928 FD->setBody(Body); 3929 if (FD->isMain()) 3930 // C and C++ allow for main to automagically return 0. 3931 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3932 FD->setHasImplicitReturnZero(true); 3933 else 3934 CheckFallThroughForFunctionDef(FD, Body); 3935 3936 if (!FD->isInvalidDecl()) 3937 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3938 3939 // C++ [basic.def.odr]p2: 3940 // [...] A virtual member function is used if it is not pure. [...] 3941 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3942 if (Method->isVirtual() && !Method->isPure()) 3943 MarkDeclarationReferenced(Method->getLocation(), Method); 3944 3945 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3946 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3947 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3948 MD->setBody(Body); 3949 CheckFallThroughForFunctionDef(MD, Body); 3950 MD->setEndLoc(Body->getLocEnd()); 3951 3952 if (!MD->isInvalidDecl()) 3953 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3954 } else { 3955 Body->Destroy(Context); 3956 return DeclPtrTy(); 3957 } 3958 if (!IsInstantiation) 3959 PopDeclContext(); 3960 3961 // Verify and clean out per-function state. 3962 3963 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3964 3965 // Check goto/label use. 3966 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3967 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3968 LabelStmt *L = I->second; 3969 3970 // Verify that we have no forward references left. If so, there was a goto 3971 // or address of a label taken, but no definition of it. Label fwd 3972 // definitions are indicated with a null substmt. 3973 if (L->getSubStmt() != 0) 3974 continue; 3975 3976 // Emit error. 3977 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3978 3979 // At this point, we have gotos that use the bogus label. Stitch it into 3980 // the function body so that they aren't leaked and that the AST is well 3981 // formed. 3982 if (Body == 0) { 3983 // The whole function wasn't parsed correctly, just delete this. 3984 L->Destroy(Context); 3985 continue; 3986 } 3987 3988 // Otherwise, the body is valid: we want to stitch the label decl into the 3989 // function somewhere so that it is properly owned and so that the goto 3990 // has a valid target. Do this by creating a new compound stmt with the 3991 // label in it. 3992 3993 // Give the label a sub-statement. 3994 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3995 3996 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3997 cast<CXXTryStmt>(Body)->getTryBlock() : 3998 cast<CompoundStmt>(Body); 3999 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4000 Elements.push_back(L); 4001 Compound->setStmts(Context, &Elements[0], Elements.size()); 4002 } 4003 FunctionLabelMap.clear(); 4004 4005 if (!Body) return D; 4006 4007 // Verify that that gotos and switch cases don't jump into scopes illegally. 4008 if (CurFunctionNeedsScopeChecking) 4009 DiagnoseInvalidJumps(Body); 4010 4011 // C++ constructors that have function-try-blocks can't have return 4012 // statements in the handlers of that block. (C++ [except.handle]p14) 4013 // Verify this. 4014 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4015 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4016 4017 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4018 computeBaseOrMembersToDestroy(Destructor); 4019 return D; 4020} 4021 4022/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4023/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4024NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4025 IdentifierInfo &II, Scope *S) { 4026 // Before we produce a declaration for an implicitly defined 4027 // function, see whether there was a locally-scoped declaration of 4028 // this name as a function or variable. If so, use that 4029 // (non-visible) declaration, and complain about it. 4030 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4031 = LocallyScopedExternalDecls.find(&II); 4032 if (Pos != LocallyScopedExternalDecls.end()) { 4033 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4034 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4035 return Pos->second; 4036 } 4037 4038 // Extension in C99. Legal in C90, but warn about it. 4039 if (II.getName().startswith("__builtin_")) 4040 Diag(Loc, diag::warn_builtin_unknown) << &II; 4041 else if (getLangOptions().C99) 4042 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4043 else 4044 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4045 4046 // Set a Declarator for the implicit definition: int foo(); 4047 const char *Dummy; 4048 DeclSpec DS; 4049 unsigned DiagID; 4050 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4051 Error = Error; // Silence warning. 4052 assert(!Error && "Error setting up implicit decl!"); 4053 Declarator D(DS, Declarator::BlockContext); 4054 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4055 0, 0, false, SourceLocation(), 4056 false, 0,0,0, Loc, Loc, D), 4057 SourceLocation()); 4058 D.SetIdentifier(&II, Loc); 4059 4060 // Insert this function into translation-unit scope. 4061 4062 DeclContext *PrevDC = CurContext; 4063 CurContext = Context.getTranslationUnitDecl(); 4064 4065 FunctionDecl *FD = 4066 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4067 FD->setImplicit(); 4068 4069 CurContext = PrevDC; 4070 4071 AddKnownFunctionAttributes(FD); 4072 4073 return FD; 4074} 4075 4076/// \brief Adds any function attributes that we know a priori based on 4077/// the declaration of this function. 4078/// 4079/// These attributes can apply both to implicitly-declared builtins 4080/// (like __builtin___printf_chk) or to library-declared functions 4081/// like NSLog or printf. 4082void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4083 if (FD->isInvalidDecl()) 4084 return; 4085 4086 // If this is a built-in function, map its builtin attributes to 4087 // actual attributes. 4088 if (unsigned BuiltinID = FD->getBuiltinID()) { 4089 // Handle printf-formatting attributes. 4090 unsigned FormatIdx; 4091 bool HasVAListArg; 4092 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4093 if (!FD->getAttr<FormatAttr>()) 4094 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4095 HasVAListArg ? 0 : FormatIdx + 2)); 4096 } 4097 4098 // Mark const if we don't care about errno and that is the only 4099 // thing preventing the function from being const. This allows 4100 // IRgen to use LLVM intrinsics for such functions. 4101 if (!getLangOptions().MathErrno && 4102 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4103 if (!FD->getAttr<ConstAttr>()) 4104 FD->addAttr(::new (Context) ConstAttr()); 4105 } 4106 4107 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4108 FD->addAttr(::new (Context) NoReturnAttr()); 4109 } 4110 4111 IdentifierInfo *Name = FD->getIdentifier(); 4112 if (!Name) 4113 return; 4114 if ((!getLangOptions().CPlusPlus && 4115 FD->getDeclContext()->isTranslationUnit()) || 4116 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4117 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4118 LinkageSpecDecl::lang_c)) { 4119 // Okay: this could be a libc/libm/Objective-C function we know 4120 // about. 4121 } else 4122 return; 4123 4124 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4125 // FIXME: NSLog and NSLogv should be target specific 4126 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4127 // FIXME: We known better than our headers. 4128 const_cast<FormatAttr *>(Format)->setType("printf"); 4129 } else 4130 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4131 Name->isStr("NSLogv") ? 0 : 2)); 4132 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4133 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4134 // target-specific builtins, perhaps? 4135 if (!FD->getAttr<FormatAttr>()) 4136 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4137 Name->isStr("vasprintf") ? 0 : 3)); 4138 } 4139} 4140 4141TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4142 DeclaratorInfo *DInfo) { 4143 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4144 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4145 4146 if (!DInfo) { 4147 assert(D.isInvalidType() && "no declarator info for valid type"); 4148 DInfo = Context.getTrivialDeclaratorInfo(T); 4149 } 4150 4151 // Scope manipulation handled by caller. 4152 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4153 D.getIdentifierLoc(), 4154 D.getIdentifier(), 4155 DInfo); 4156 4157 if (const TagType *TT = T->getAs<TagType>()) { 4158 TagDecl *TD = TT->getDecl(); 4159 4160 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4161 // keep track of the TypedefDecl. 4162 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4163 TD->setTypedefForAnonDecl(NewTD); 4164 } 4165 4166 if (D.isInvalidType()) 4167 NewTD->setInvalidDecl(); 4168 return NewTD; 4169} 4170 4171 4172/// \brief Determine whether a tag with a given kind is acceptable 4173/// as a redeclaration of the given tag declaration. 4174/// 4175/// \returns true if the new tag kind is acceptable, false otherwise. 4176bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4177 TagDecl::TagKind NewTag, 4178 SourceLocation NewTagLoc, 4179 const IdentifierInfo &Name) { 4180 // C++ [dcl.type.elab]p3: 4181 // The class-key or enum keyword present in the 4182 // elaborated-type-specifier shall agree in kind with the 4183 // declaration to which the name in theelaborated-type-specifier 4184 // refers. This rule also applies to the form of 4185 // elaborated-type-specifier that declares a class-name or 4186 // friend class since it can be construed as referring to the 4187 // definition of the class. Thus, in any 4188 // elaborated-type-specifier, the enum keyword shall be used to 4189 // refer to an enumeration (7.2), the union class-keyshall be 4190 // used to refer to a union (clause 9), and either the class or 4191 // struct class-key shall be used to refer to a class (clause 9) 4192 // declared using the class or struct class-key. 4193 TagDecl::TagKind OldTag = Previous->getTagKind(); 4194 if (OldTag == NewTag) 4195 return true; 4196 4197 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4198 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4199 // Warn about the struct/class tag mismatch. 4200 bool isTemplate = false; 4201 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4202 isTemplate = Record->getDescribedClassTemplate(); 4203 4204 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4205 << (NewTag == TagDecl::TK_class) 4206 << isTemplate << &Name 4207 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4208 OldTag == TagDecl::TK_class? "class" : "struct"); 4209 Diag(Previous->getLocation(), diag::note_previous_use); 4210 return true; 4211 } 4212 return false; 4213} 4214 4215/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4216/// former case, Name will be non-null. In the later case, Name will be null. 4217/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4218/// reference/declaration/definition of a tag. 4219Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4220 SourceLocation KWLoc, const CXXScopeSpec &SS, 4221 IdentifierInfo *Name, SourceLocation NameLoc, 4222 AttributeList *Attr, AccessSpecifier AS, 4223 MultiTemplateParamsArg TemplateParameterLists, 4224 bool &OwnedDecl, bool &IsDependent) { 4225 // If this is not a definition, it must have a name. 4226 assert((Name != 0 || TUK == TUK_Definition) && 4227 "Nameless record must be a definition!"); 4228 4229 OwnedDecl = false; 4230 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4231 4232 // FIXME: Check explicit specializations more carefully. 4233 bool isExplicitSpecialization = false; 4234 if (TUK != TUK_Reference) { 4235 if (TemplateParameterList *TemplateParams 4236 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4237 (TemplateParameterList**)TemplateParameterLists.get(), 4238 TemplateParameterLists.size(), 4239 isExplicitSpecialization)) { 4240 if (TemplateParams->size() > 0) { 4241 // This is a declaration or definition of a class template (which may 4242 // be a member of another template). 4243 OwnedDecl = false; 4244 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4245 SS, Name, NameLoc, Attr, 4246 TemplateParams, 4247 AS); 4248 TemplateParameterLists.release(); 4249 return Result.get(); 4250 } else { 4251 // The "template<>" header is extraneous. 4252 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4253 << ElaboratedType::getNameForTagKind(Kind) << Name; 4254 isExplicitSpecialization = true; 4255 } 4256 } 4257 4258 TemplateParameterLists.release(); 4259 } 4260 4261 DeclContext *SearchDC = CurContext; 4262 DeclContext *DC = CurContext; 4263 NamedDecl *PrevDecl = 0; 4264 bool isStdBadAlloc = false; 4265 bool Invalid = false; 4266 4267 bool RedeclarationOnly = (TUK != TUK_Reference); 4268 4269 if (Name && SS.isNotEmpty()) { 4270 // We have a nested-name tag ('struct foo::bar'). 4271 4272 // Check for invalid 'foo::'. 4273 if (SS.isInvalid()) { 4274 Name = 0; 4275 goto CreateNewDecl; 4276 } 4277 4278 // If this is a friend or a reference to a class in a dependent 4279 // context, don't try to make a decl for it. 4280 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4281 DC = computeDeclContext(SS, false); 4282 if (!DC) { 4283 IsDependent = true; 4284 return DeclPtrTy(); 4285 } 4286 } 4287 4288 if (RequireCompleteDeclContext(SS)) 4289 return DeclPtrTy::make((Decl *)0); 4290 4291 DC = computeDeclContext(SS, true); 4292 SearchDC = DC; 4293 // Look-up name inside 'foo::'. 4294 LookupResult R; 4295 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4296 4297 if (R.isAmbiguous()) { 4298 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4299 return DeclPtrTy(); 4300 } 4301 4302 if (R.getKind() == LookupResult::Found) 4303 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4304 4305 // A tag 'foo::bar' must already exist. 4306 if (!PrevDecl) { 4307 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4308 Name = 0; 4309 Invalid = true; 4310 goto CreateNewDecl; 4311 } 4312 } else if (Name) { 4313 // If this is a named struct, check to see if there was a previous forward 4314 // declaration or definition. 4315 // FIXME: We're looking into outer scopes here, even when we 4316 // shouldn't be. Doing so can result in ambiguities that we 4317 // shouldn't be diagnosing. 4318 LookupResult R; 4319 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4320 if (R.isAmbiguous()) { 4321 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4322 // FIXME: This is not best way to recover from case like: 4323 // 4324 // struct S s; 4325 // 4326 // causes needless "incomplete type" error later. 4327 Name = 0; 4328 PrevDecl = 0; 4329 Invalid = true; 4330 } else 4331 PrevDecl = R.getAsSingleDecl(Context); 4332 4333 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4334 // FIXME: This makes sure that we ignore the contexts associated 4335 // with C structs, unions, and enums when looking for a matching 4336 // tag declaration or definition. See the similar lookup tweak 4337 // in Sema::LookupName; is there a better way to deal with this? 4338 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4339 SearchDC = SearchDC->getParent(); 4340 } 4341 } 4342 4343 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4344 // Maybe we will complain about the shadowed template parameter. 4345 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4346 // Just pretend that we didn't see the previous declaration. 4347 PrevDecl = 0; 4348 } 4349 4350 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4351 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4352 // This is a declaration of or a reference to "std::bad_alloc". 4353 isStdBadAlloc = true; 4354 4355 if (!PrevDecl && StdBadAlloc) { 4356 // std::bad_alloc has been implicitly declared (but made invisible to 4357 // name lookup). Fill in this implicit declaration as the previous 4358 // declaration, so that the declarations get chained appropriately. 4359 PrevDecl = StdBadAlloc; 4360 } 4361 } 4362 4363 if (PrevDecl) { 4364 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4365 // If this is a use of a previous tag, or if the tag is already declared 4366 // in the same scope (so that the definition/declaration completes or 4367 // rementions the tag), reuse the decl. 4368 if (TUK == TUK_Reference || TUK == TUK_Friend || 4369 isDeclInScope(PrevDecl, SearchDC, S)) { 4370 // Make sure that this wasn't declared as an enum and now used as a 4371 // struct or something similar. 4372 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4373 bool SafeToContinue 4374 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4375 Kind != TagDecl::TK_enum); 4376 if (SafeToContinue) 4377 Diag(KWLoc, diag::err_use_with_wrong_tag) 4378 << Name 4379 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4380 PrevTagDecl->getKindName()); 4381 else 4382 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4383 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4384 4385 if (SafeToContinue) 4386 Kind = PrevTagDecl->getTagKind(); 4387 else { 4388 // Recover by making this an anonymous redefinition. 4389 Name = 0; 4390 PrevDecl = 0; 4391 Invalid = true; 4392 } 4393 } 4394 4395 if (!Invalid) { 4396 // If this is a use, just return the declaration we found. 4397 4398 // FIXME: In the future, return a variant or some other clue 4399 // for the consumer of this Decl to know it doesn't own it. 4400 // For our current ASTs this shouldn't be a problem, but will 4401 // need to be changed with DeclGroups. 4402 if (TUK == TUK_Reference || TUK == TUK_Friend) 4403 return DeclPtrTy::make(PrevDecl); 4404 4405 // Diagnose attempts to redefine a tag. 4406 if (TUK == TUK_Definition) { 4407 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4408 // If we're defining a specialization and the previous definition 4409 // is from an implicit instantiation, don't emit an error 4410 // here; we'll catch this in the general case below. 4411 if (!isExplicitSpecialization || 4412 !isa<CXXRecordDecl>(Def) || 4413 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4414 == TSK_ExplicitSpecialization) { 4415 Diag(NameLoc, diag::err_redefinition) << Name; 4416 Diag(Def->getLocation(), diag::note_previous_definition); 4417 // If this is a redefinition, recover by making this 4418 // struct be anonymous, which will make any later 4419 // references get the previous definition. 4420 Name = 0; 4421 PrevDecl = 0; 4422 Invalid = true; 4423 } 4424 } else { 4425 // If the type is currently being defined, complain 4426 // about a nested redefinition. 4427 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4428 if (Tag->isBeingDefined()) { 4429 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4430 Diag(PrevTagDecl->getLocation(), 4431 diag::note_previous_definition); 4432 Name = 0; 4433 PrevDecl = 0; 4434 Invalid = true; 4435 } 4436 } 4437 4438 // Okay, this is definition of a previously declared or referenced 4439 // tag PrevDecl. We're going to create a new Decl for it. 4440 } 4441 } 4442 // If we get here we have (another) forward declaration or we 4443 // have a definition. Just create a new decl. 4444 4445 } else { 4446 // If we get here, this is a definition of a new tag type in a nested 4447 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4448 // new decl/type. We set PrevDecl to NULL so that the entities 4449 // have distinct types. 4450 PrevDecl = 0; 4451 } 4452 // If we get here, we're going to create a new Decl. If PrevDecl 4453 // is non-NULL, it's a definition of the tag declared by 4454 // PrevDecl. If it's NULL, we have a new definition. 4455 } else { 4456 // PrevDecl is a namespace, template, or anything else 4457 // that lives in the IDNS_Tag identifier namespace. 4458 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4459 // The tag name clashes with a namespace name, issue an error and 4460 // recover by making this tag be anonymous. 4461 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4462 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4463 Name = 0; 4464 PrevDecl = 0; 4465 Invalid = true; 4466 } else { 4467 // The existing declaration isn't relevant to us; we're in a 4468 // new scope, so clear out the previous declaration. 4469 PrevDecl = 0; 4470 } 4471 } 4472 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4473 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4474 // C++ [basic.scope.pdecl]p5: 4475 // -- for an elaborated-type-specifier of the form 4476 // 4477 // class-key identifier 4478 // 4479 // if the elaborated-type-specifier is used in the 4480 // decl-specifier-seq or parameter-declaration-clause of a 4481 // function defined in namespace scope, the identifier is 4482 // declared as a class-name in the namespace that contains 4483 // the declaration; otherwise, except as a friend 4484 // declaration, the identifier is declared in the smallest 4485 // non-class, non-function-prototype scope that contains the 4486 // declaration. 4487 // 4488 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4489 // C structs and unions. 4490 // 4491 // GNU C also supports this behavior as part of its incomplete 4492 // enum types extension, while GNU C++ does not. 4493 // 4494 // Find the context where we'll be declaring the tag. 4495 // FIXME: We would like to maintain the current DeclContext as the 4496 // lexical context, 4497 while (SearchDC->isRecord()) 4498 SearchDC = SearchDC->getParent(); 4499 4500 // Find the scope where we'll be declaring the tag. 4501 while (S->isClassScope() || 4502 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4503 ((S->getFlags() & Scope::DeclScope) == 0) || 4504 (S->getEntity() && 4505 ((DeclContext *)S->getEntity())->isTransparentContext())) 4506 S = S->getParent(); 4507 4508 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4509 // C++ [namespace.memdef]p3: 4510 // If a friend declaration in a non-local class first declares a 4511 // class or function, the friend class or function is a member of 4512 // the innermost enclosing namespace. 4513 while (!SearchDC->isFileContext()) 4514 SearchDC = SearchDC->getParent(); 4515 4516 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4517 while (S->getEntity() != SearchDC) 4518 S = S->getParent(); 4519 } 4520 4521CreateNewDecl: 4522 4523 // If there is an identifier, use the location of the identifier as the 4524 // location of the decl, otherwise use the location of the struct/union 4525 // keyword. 4526 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4527 4528 // Otherwise, create a new declaration. If there is a previous 4529 // declaration of the same entity, the two will be linked via 4530 // PrevDecl. 4531 TagDecl *New; 4532 4533 if (Kind == TagDecl::TK_enum) { 4534 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4535 // enum X { A, B, C } D; D should chain to X. 4536 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4537 cast_or_null<EnumDecl>(PrevDecl)); 4538 // If this is an undefined enum, warn. 4539 if (TUK != TUK_Definition && !Invalid) { 4540 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4541 : diag::ext_forward_ref_enum; 4542 Diag(Loc, DK); 4543 } 4544 } else { 4545 // struct/union/class 4546 4547 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4548 // struct X { int A; } D; D should chain to X. 4549 if (getLangOptions().CPlusPlus) { 4550 // FIXME: Look for a way to use RecordDecl for simple structs. 4551 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4552 cast_or_null<CXXRecordDecl>(PrevDecl)); 4553 4554 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4555 StdBadAlloc = cast<CXXRecordDecl>(New); 4556 } else 4557 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4558 cast_or_null<RecordDecl>(PrevDecl)); 4559 } 4560 4561 if (Kind != TagDecl::TK_enum) { 4562 // Handle #pragma pack: if the #pragma pack stack has non-default 4563 // alignment, make up a packed attribute for this decl. These 4564 // attributes are checked when the ASTContext lays out the 4565 // structure. 4566 // 4567 // It is important for implementing the correct semantics that this 4568 // happen here (in act on tag decl). The #pragma pack stack is 4569 // maintained as a result of parser callbacks which can occur at 4570 // many points during the parsing of a struct declaration (because 4571 // the #pragma tokens are effectively skipped over during the 4572 // parsing of the struct). 4573 if (unsigned Alignment = getPragmaPackAlignment()) 4574 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4575 } 4576 4577 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4578 // C++ [dcl.typedef]p3: 4579 // [...] Similarly, in a given scope, a class or enumeration 4580 // shall not be declared with the same name as a typedef-name 4581 // that is declared in that scope and refers to a type other 4582 // than the class or enumeration itself. 4583 LookupResult Lookup; 4584 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4585 TypedefDecl *PrevTypedef = 0; 4586 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4587 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4588 4589 NamedDecl *PrevTypedefNamed = PrevTypedef; 4590 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4591 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4592 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4593 Diag(Loc, diag::err_tag_definition_of_typedef) 4594 << Context.getTypeDeclType(New) 4595 << PrevTypedef->getUnderlyingType(); 4596 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4597 Invalid = true; 4598 } 4599 } 4600 4601 // If this is a specialization of a member class (of a class template), 4602 // check the specialization. 4603 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4604 Invalid = true; 4605 4606 if (Invalid) 4607 New->setInvalidDecl(); 4608 4609 if (Attr) 4610 ProcessDeclAttributeList(S, New, Attr); 4611 4612 // If we're declaring or defining a tag in function prototype scope 4613 // in C, note that this type can only be used within the function. 4614 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4615 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4616 4617 // Set the lexical context. If the tag has a C++ scope specifier, the 4618 // lexical context will be different from the semantic context. 4619 New->setLexicalDeclContext(CurContext); 4620 4621 // Mark this as a friend decl if applicable. 4622 if (TUK == TUK_Friend) 4623 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4624 4625 // Set the access specifier. 4626 if (!Invalid && TUK != TUK_Friend) 4627 SetMemberAccessSpecifier(New, PrevDecl, AS); 4628 4629 if (TUK == TUK_Definition) 4630 New->startDefinition(); 4631 4632 // If this has an identifier, add it to the scope stack. 4633 if (TUK == TUK_Friend) { 4634 // We might be replacing an existing declaration in the lookup tables; 4635 // if so, borrow its access specifier. 4636 if (PrevDecl) 4637 New->setAccess(PrevDecl->getAccess()); 4638 4639 // Friend tag decls are visible in fairly strange ways. 4640 if (!CurContext->isDependentContext()) { 4641 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4642 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4643 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4644 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4645 } 4646 } else if (Name) { 4647 S = getNonFieldDeclScope(S); 4648 PushOnScopeChains(New, S); 4649 } else { 4650 CurContext->addDecl(New); 4651 } 4652 4653 // If this is the C FILE type, notify the AST context. 4654 if (IdentifierInfo *II = New->getIdentifier()) 4655 if (!New->isInvalidDecl() && 4656 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4657 II->isStr("FILE")) 4658 Context.setFILEDecl(New); 4659 4660 OwnedDecl = true; 4661 return DeclPtrTy::make(New); 4662} 4663 4664void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4665 AdjustDeclIfTemplate(TagD); 4666 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4667 4668 // Enter the tag context. 4669 PushDeclContext(S, Tag); 4670 4671 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4672 FieldCollector->StartClass(); 4673 4674 if (Record->getIdentifier()) { 4675 // C++ [class]p2: 4676 // [...] The class-name is also inserted into the scope of the 4677 // class itself; this is known as the injected-class-name. For 4678 // purposes of access checking, the injected-class-name is treated 4679 // as if it were a public member name. 4680 CXXRecordDecl *InjectedClassName 4681 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4682 CurContext, Record->getLocation(), 4683 Record->getIdentifier(), 4684 Record->getTagKeywordLoc(), 4685 Record); 4686 InjectedClassName->setImplicit(); 4687 InjectedClassName->setAccess(AS_public); 4688 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4689 InjectedClassName->setDescribedClassTemplate(Template); 4690 PushOnScopeChains(InjectedClassName, S); 4691 assert(InjectedClassName->isInjectedClassName() && 4692 "Broken injected-class-name"); 4693 } 4694 } 4695} 4696 4697void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4698 SourceLocation RBraceLoc) { 4699 AdjustDeclIfTemplate(TagD); 4700 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4701 Tag->setRBraceLoc(RBraceLoc); 4702 4703 if (isa<CXXRecordDecl>(Tag)) 4704 FieldCollector->FinishClass(); 4705 4706 // Exit this scope of this tag's definition. 4707 PopDeclContext(); 4708 4709 // Notify the consumer that we've defined a tag. 4710 Consumer.HandleTagDeclDefinition(Tag); 4711} 4712 4713// Note that FieldName may be null for anonymous bitfields. 4714bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4715 QualType FieldTy, const Expr *BitWidth, 4716 bool *ZeroWidth) { 4717 // Default to true; that shouldn't confuse checks for emptiness 4718 if (ZeroWidth) 4719 *ZeroWidth = true; 4720 4721 // C99 6.7.2.1p4 - verify the field type. 4722 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4723 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4724 // Handle incomplete types with specific error. 4725 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4726 return true; 4727 if (FieldName) 4728 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4729 << FieldName << FieldTy << BitWidth->getSourceRange(); 4730 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4731 << FieldTy << BitWidth->getSourceRange(); 4732 } 4733 4734 // If the bit-width is type- or value-dependent, don't try to check 4735 // it now. 4736 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4737 return false; 4738 4739 llvm::APSInt Value; 4740 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4741 return true; 4742 4743 if (Value != 0 && ZeroWidth) 4744 *ZeroWidth = false; 4745 4746 // Zero-width bitfield is ok for anonymous field. 4747 if (Value == 0 && FieldName) 4748 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4749 4750 if (Value.isSigned() && Value.isNegative()) { 4751 if (FieldName) 4752 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4753 << FieldName << Value.toString(10); 4754 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4755 << Value.toString(10); 4756 } 4757 4758 if (!FieldTy->isDependentType()) { 4759 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4760 if (Value.getZExtValue() > TypeSize) { 4761 if (FieldName) 4762 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4763 << FieldName << (unsigned)TypeSize; 4764 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4765 << (unsigned)TypeSize; 4766 } 4767 } 4768 4769 return false; 4770} 4771 4772/// ActOnField - Each field of a struct/union/class is passed into this in order 4773/// to create a FieldDecl object for it. 4774Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4775 SourceLocation DeclStart, 4776 Declarator &D, ExprTy *BitfieldWidth) { 4777 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4778 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4779 AS_public); 4780 return DeclPtrTy::make(Res); 4781} 4782 4783/// HandleField - Analyze a field of a C struct or a C++ data member. 4784/// 4785FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4786 SourceLocation DeclStart, 4787 Declarator &D, Expr *BitWidth, 4788 AccessSpecifier AS) { 4789 IdentifierInfo *II = D.getIdentifier(); 4790 SourceLocation Loc = DeclStart; 4791 if (II) Loc = D.getIdentifierLoc(); 4792 4793 DeclaratorInfo *DInfo = 0; 4794 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4795 if (getLangOptions().CPlusPlus) 4796 CheckExtraCXXDefaultArguments(D); 4797 4798 DiagnoseFunctionSpecifiers(D); 4799 4800 if (D.getDeclSpec().isThreadSpecified()) 4801 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4802 4803 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4804 4805 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4806 // Maybe we will complain about the shadowed template parameter. 4807 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4808 // Just pretend that we didn't see the previous declaration. 4809 PrevDecl = 0; 4810 } 4811 4812 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4813 PrevDecl = 0; 4814 4815 bool Mutable 4816 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4817 SourceLocation TSSL = D.getSourceRange().getBegin(); 4818 FieldDecl *NewFD 4819 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4820 AS, PrevDecl, &D); 4821 if (NewFD->isInvalidDecl() && PrevDecl) { 4822 // Don't introduce NewFD into scope; there's already something 4823 // with the same name in the same scope. 4824 } else if (II) { 4825 PushOnScopeChains(NewFD, S); 4826 } else 4827 Record->addDecl(NewFD); 4828 4829 return NewFD; 4830} 4831 4832/// \brief Build a new FieldDecl and check its well-formedness. 4833/// 4834/// This routine builds a new FieldDecl given the fields name, type, 4835/// record, etc. \p PrevDecl should refer to any previous declaration 4836/// with the same name and in the same scope as the field to be 4837/// created. 4838/// 4839/// \returns a new FieldDecl. 4840/// 4841/// \todo The Declarator argument is a hack. It will be removed once 4842FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4843 DeclaratorInfo *DInfo, 4844 RecordDecl *Record, SourceLocation Loc, 4845 bool Mutable, Expr *BitWidth, 4846 SourceLocation TSSL, 4847 AccessSpecifier AS, NamedDecl *PrevDecl, 4848 Declarator *D) { 4849 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4850 bool InvalidDecl = false; 4851 if (D) InvalidDecl = D->isInvalidType(); 4852 4853 // If we receive a broken type, recover by assuming 'int' and 4854 // marking this declaration as invalid. 4855 if (T.isNull()) { 4856 InvalidDecl = true; 4857 T = Context.IntTy; 4858 } 4859 4860 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4861 // than a variably modified type. 4862 if (T->isVariablyModifiedType()) { 4863 bool SizeIsNegative; 4864 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4865 SizeIsNegative); 4866 if (!FixedTy.isNull()) { 4867 Diag(Loc, diag::warn_illegal_constant_array_size); 4868 T = FixedTy; 4869 } else { 4870 if (SizeIsNegative) 4871 Diag(Loc, diag::err_typecheck_negative_array_size); 4872 else 4873 Diag(Loc, diag::err_typecheck_field_variable_size); 4874 InvalidDecl = true; 4875 } 4876 } 4877 4878 // Fields can not have abstract class types 4879 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4880 AbstractFieldType)) 4881 InvalidDecl = true; 4882 4883 bool ZeroWidth = false; 4884 // If this is declared as a bit-field, check the bit-field. 4885 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4886 InvalidDecl = true; 4887 DeleteExpr(BitWidth); 4888 BitWidth = 0; 4889 ZeroWidth = false; 4890 } 4891 4892 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4893 BitWidth, Mutable); 4894 if (InvalidDecl) 4895 NewFD->setInvalidDecl(); 4896 4897 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4898 Diag(Loc, diag::err_duplicate_member) << II; 4899 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4900 NewFD->setInvalidDecl(); 4901 } 4902 4903 if (getLangOptions().CPlusPlus) { 4904 QualType EltTy = Context.getBaseElementType(T); 4905 4906 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4907 4908 if (!T->isPODType()) 4909 CXXRecord->setPOD(false); 4910 if (!ZeroWidth) 4911 CXXRecord->setEmpty(false); 4912 4913 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4914 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4915 4916 if (!RDecl->hasTrivialConstructor()) 4917 CXXRecord->setHasTrivialConstructor(false); 4918 if (!RDecl->hasTrivialCopyConstructor()) 4919 CXXRecord->setHasTrivialCopyConstructor(false); 4920 if (!RDecl->hasTrivialCopyAssignment()) 4921 CXXRecord->setHasTrivialCopyAssignment(false); 4922 if (!RDecl->hasTrivialDestructor()) 4923 CXXRecord->setHasTrivialDestructor(false); 4924 4925 // C++ 9.5p1: An object of a class with a non-trivial 4926 // constructor, a non-trivial copy constructor, a non-trivial 4927 // destructor, or a non-trivial copy assignment operator 4928 // cannot be a member of a union, nor can an array of such 4929 // objects. 4930 // TODO: C++0x alters this restriction significantly. 4931 if (Record->isUnion()) { 4932 // We check for copy constructors before constructors 4933 // because otherwise we'll never get complaints about 4934 // copy constructors. 4935 4936 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4937 4938 CXXSpecialMember member; 4939 if (!RDecl->hasTrivialCopyConstructor()) 4940 member = CXXCopyConstructor; 4941 else if (!RDecl->hasTrivialConstructor()) 4942 member = CXXDefaultConstructor; 4943 else if (!RDecl->hasTrivialCopyAssignment()) 4944 member = CXXCopyAssignment; 4945 else if (!RDecl->hasTrivialDestructor()) 4946 member = CXXDestructor; 4947 else 4948 member = invalid; 4949 4950 if (member != invalid) { 4951 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4952 DiagnoseNontrivial(RT, member); 4953 NewFD->setInvalidDecl(); 4954 } 4955 } 4956 } 4957 } 4958 4959 // FIXME: We need to pass in the attributes given an AST 4960 // representation, not a parser representation. 4961 if (D) 4962 // FIXME: What to pass instead of TUScope? 4963 ProcessDeclAttributes(TUScope, NewFD, *D); 4964 4965 if (T.isObjCGCWeak()) 4966 Diag(Loc, diag::warn_attribute_weak_on_field); 4967 4968 NewFD->setAccess(AS); 4969 4970 // C++ [dcl.init.aggr]p1: 4971 // An aggregate is an array or a class (clause 9) with [...] no 4972 // private or protected non-static data members (clause 11). 4973 // A POD must be an aggregate. 4974 if (getLangOptions().CPlusPlus && 4975 (AS == AS_private || AS == AS_protected)) { 4976 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4977 CXXRecord->setAggregate(false); 4978 CXXRecord->setPOD(false); 4979 } 4980 4981 return NewFD; 4982} 4983 4984/// DiagnoseNontrivial - Given that a class has a non-trivial 4985/// special member, figure out why. 4986void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4987 QualType QT(T, 0U); 4988 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4989 4990 // Check whether the member was user-declared. 4991 switch (member) { 4992 case CXXDefaultConstructor: 4993 if (RD->hasUserDeclaredConstructor()) { 4994 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4995 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 4996 const FunctionDecl *body = 0; 4997 ci->getBody(body); 4998 if (!body || 4999 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5000 SourceLocation CtorLoc = ci->getLocation(); 5001 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5002 return; 5003 } 5004 } 5005 5006 assert(0 && "found no user-declared constructors"); 5007 return; 5008 } 5009 break; 5010 5011 case CXXCopyConstructor: 5012 if (RD->hasUserDeclaredCopyConstructor()) { 5013 SourceLocation CtorLoc = 5014 RD->getCopyConstructor(Context, 0)->getLocation(); 5015 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5016 return; 5017 } 5018 break; 5019 5020 case CXXCopyAssignment: 5021 if (RD->hasUserDeclaredCopyAssignment()) { 5022 // FIXME: this should use the location of the copy 5023 // assignment, not the type. 5024 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5025 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5026 return; 5027 } 5028 break; 5029 5030 case CXXDestructor: 5031 if (RD->hasUserDeclaredDestructor()) { 5032 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5033 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5034 return; 5035 } 5036 break; 5037 } 5038 5039 typedef CXXRecordDecl::base_class_iterator base_iter; 5040 5041 // Virtual bases and members inhibit trivial copying/construction, 5042 // but not trivial destruction. 5043 if (member != CXXDestructor) { 5044 // Check for virtual bases. vbases includes indirect virtual bases, 5045 // so we just iterate through the direct bases. 5046 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5047 if (bi->isVirtual()) { 5048 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5049 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5050 return; 5051 } 5052 5053 // Check for virtual methods. 5054 typedef CXXRecordDecl::method_iterator meth_iter; 5055 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5056 ++mi) { 5057 if (mi->isVirtual()) { 5058 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5059 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5060 return; 5061 } 5062 } 5063 } 5064 5065 bool (CXXRecordDecl::*hasTrivial)() const; 5066 switch (member) { 5067 case CXXDefaultConstructor: 5068 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5069 case CXXCopyConstructor: 5070 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5071 case CXXCopyAssignment: 5072 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5073 case CXXDestructor: 5074 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5075 default: 5076 assert(0 && "unexpected special member"); return; 5077 } 5078 5079 // Check for nontrivial bases (and recurse). 5080 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5081 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5082 assert(BaseRT && "Don't know how to handle dependent bases"); 5083 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5084 if (!(BaseRecTy->*hasTrivial)()) { 5085 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5086 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5087 DiagnoseNontrivial(BaseRT, member); 5088 return; 5089 } 5090 } 5091 5092 // Check for nontrivial members (and recurse). 5093 typedef RecordDecl::field_iterator field_iter; 5094 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5095 ++fi) { 5096 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5097 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5098 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5099 5100 if (!(EltRD->*hasTrivial)()) { 5101 SourceLocation FLoc = (*fi)->getLocation(); 5102 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5103 DiagnoseNontrivial(EltRT, member); 5104 return; 5105 } 5106 } 5107 } 5108 5109 assert(0 && "found no explanation for non-trivial member"); 5110} 5111 5112/// TranslateIvarVisibility - Translate visibility from a token ID to an 5113/// AST enum value. 5114static ObjCIvarDecl::AccessControl 5115TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5116 switch (ivarVisibility) { 5117 default: assert(0 && "Unknown visitibility kind"); 5118 case tok::objc_private: return ObjCIvarDecl::Private; 5119 case tok::objc_public: return ObjCIvarDecl::Public; 5120 case tok::objc_protected: return ObjCIvarDecl::Protected; 5121 case tok::objc_package: return ObjCIvarDecl::Package; 5122 } 5123} 5124 5125/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5126/// in order to create an IvarDecl object for it. 5127Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5128 SourceLocation DeclStart, 5129 DeclPtrTy IntfDecl, 5130 Declarator &D, ExprTy *BitfieldWidth, 5131 tok::ObjCKeywordKind Visibility) { 5132 5133 IdentifierInfo *II = D.getIdentifier(); 5134 Expr *BitWidth = (Expr*)BitfieldWidth; 5135 SourceLocation Loc = DeclStart; 5136 if (II) Loc = D.getIdentifierLoc(); 5137 5138 // FIXME: Unnamed fields can be handled in various different ways, for 5139 // example, unnamed unions inject all members into the struct namespace! 5140 5141 DeclaratorInfo *DInfo = 0; 5142 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5143 5144 if (BitWidth) { 5145 // 6.7.2.1p3, 6.7.2.1p4 5146 if (VerifyBitField(Loc, II, T, BitWidth)) { 5147 D.setInvalidType(); 5148 DeleteExpr(BitWidth); 5149 BitWidth = 0; 5150 } 5151 } else { 5152 // Not a bitfield. 5153 5154 // validate II. 5155 5156 } 5157 5158 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5159 // than a variably modified type. 5160 if (T->isVariablyModifiedType()) { 5161 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5162 D.setInvalidType(); 5163 } 5164 5165 // Get the visibility (access control) for this ivar. 5166 ObjCIvarDecl::AccessControl ac = 5167 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5168 : ObjCIvarDecl::None; 5169 // Must set ivar's DeclContext to its enclosing interface. 5170 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5171 DeclContext *EnclosingContext; 5172 if (ObjCImplementationDecl *IMPDecl = 5173 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5174 // Case of ivar declared in an implementation. Context is that of its class. 5175 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5176 assert(IDecl && "No class- ActOnIvar"); 5177 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5178 } else 5179 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5180 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5181 5182 // Construct the decl. 5183 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5184 EnclosingContext, Loc, II, T, 5185 DInfo, ac, (Expr *)BitfieldWidth); 5186 5187 if (II) { 5188 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5189 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5190 && !isa<TagDecl>(PrevDecl)) { 5191 Diag(Loc, diag::err_duplicate_member) << II; 5192 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5193 NewID->setInvalidDecl(); 5194 } 5195 } 5196 5197 // Process attributes attached to the ivar. 5198 ProcessDeclAttributes(S, NewID, D); 5199 5200 if (D.isInvalidType()) 5201 NewID->setInvalidDecl(); 5202 5203 if (II) { 5204 // FIXME: When interfaces are DeclContexts, we'll need to add 5205 // these to the interface. 5206 S->AddDecl(DeclPtrTy::make(NewID)); 5207 IdResolver.AddDecl(NewID); 5208 } 5209 5210 return DeclPtrTy::make(NewID); 5211} 5212 5213void Sema::ActOnFields(Scope* S, 5214 SourceLocation RecLoc, DeclPtrTy RecDecl, 5215 DeclPtrTy *Fields, unsigned NumFields, 5216 SourceLocation LBrac, SourceLocation RBrac, 5217 AttributeList *Attr) { 5218 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5219 assert(EnclosingDecl && "missing record or interface decl"); 5220 5221 // If the decl this is being inserted into is invalid, then it may be a 5222 // redeclaration or some other bogus case. Don't try to add fields to it. 5223 if (EnclosingDecl->isInvalidDecl()) { 5224 // FIXME: Deallocate fields? 5225 return; 5226 } 5227 5228 5229 // Verify that all the fields are okay. 5230 unsigned NumNamedMembers = 0; 5231 llvm::SmallVector<FieldDecl*, 32> RecFields; 5232 5233 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5234 for (unsigned i = 0; i != NumFields; ++i) { 5235 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5236 5237 // Get the type for the field. 5238 Type *FDTy = FD->getType().getTypePtr(); 5239 5240 if (!FD->isAnonymousStructOrUnion()) { 5241 // Remember all fields written by the user. 5242 RecFields.push_back(FD); 5243 } 5244 5245 // If the field is already invalid for some reason, don't emit more 5246 // diagnostics about it. 5247 if (FD->isInvalidDecl()) 5248 continue; 5249 5250 // C99 6.7.2.1p2: 5251 // A structure or union shall not contain a member with 5252 // incomplete or function type (hence, a structure shall not 5253 // contain an instance of itself, but may contain a pointer to 5254 // an instance of itself), except that the last member of a 5255 // structure with more than one named member may have incomplete 5256 // array type; such a structure (and any union containing, 5257 // possibly recursively, a member that is such a structure) 5258 // shall not be a member of a structure or an element of an 5259 // array. 5260 if (FDTy->isFunctionType()) { 5261 // Field declared as a function. 5262 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5263 << FD->getDeclName(); 5264 FD->setInvalidDecl(); 5265 EnclosingDecl->setInvalidDecl(); 5266 continue; 5267 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5268 Record && Record->isStruct()) { 5269 // Flexible array member. 5270 if (NumNamedMembers < 1) { 5271 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5272 << FD->getDeclName(); 5273 FD->setInvalidDecl(); 5274 EnclosingDecl->setInvalidDecl(); 5275 continue; 5276 } 5277 // Okay, we have a legal flexible array member at the end of the struct. 5278 if (Record) 5279 Record->setHasFlexibleArrayMember(true); 5280 } else if (!FDTy->isDependentType() && 5281 RequireCompleteType(FD->getLocation(), FD->getType(), 5282 diag::err_field_incomplete)) { 5283 // Incomplete type 5284 FD->setInvalidDecl(); 5285 EnclosingDecl->setInvalidDecl(); 5286 continue; 5287 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5288 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5289 // If this is a member of a union, then entire union becomes "flexible". 5290 if (Record && Record->isUnion()) { 5291 Record->setHasFlexibleArrayMember(true); 5292 } else { 5293 // If this is a struct/class and this is not the last element, reject 5294 // it. Note that GCC supports variable sized arrays in the middle of 5295 // structures. 5296 if (i != NumFields-1) 5297 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5298 << FD->getDeclName() << FD->getType(); 5299 else { 5300 // We support flexible arrays at the end of structs in 5301 // other structs as an extension. 5302 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5303 << FD->getDeclName(); 5304 if (Record) 5305 Record->setHasFlexibleArrayMember(true); 5306 } 5307 } 5308 } 5309 if (Record && FDTTy->getDecl()->hasObjectMember()) 5310 Record->setHasObjectMember(true); 5311 } else if (FDTy->isObjCInterfaceType()) { 5312 /// A field cannot be an Objective-c object 5313 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5314 FD->setInvalidDecl(); 5315 EnclosingDecl->setInvalidDecl(); 5316 continue; 5317 } else if (getLangOptions().ObjC1 && 5318 getLangOptions().getGCMode() != LangOptions::NonGC && 5319 Record && 5320 (FD->getType()->isObjCObjectPointerType() || 5321 FD->getType().isObjCGCStrong())) 5322 Record->setHasObjectMember(true); 5323 // Keep track of the number of named members. 5324 if (FD->getIdentifier()) 5325 ++NumNamedMembers; 5326 } 5327 5328 // Okay, we successfully defined 'Record'. 5329 if (Record) { 5330 Record->completeDefinition(Context); 5331 } else { 5332 ObjCIvarDecl **ClsFields = 5333 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5334 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5335 ID->setIVarList(ClsFields, RecFields.size(), Context); 5336 ID->setLocEnd(RBrac); 5337 // Add ivar's to class's DeclContext. 5338 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5339 ClsFields[i]->setLexicalDeclContext(ID); 5340 ID->addDecl(ClsFields[i]); 5341 } 5342 // Must enforce the rule that ivars in the base classes may not be 5343 // duplicates. 5344 if (ID->getSuperClass()) { 5345 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5346 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5347 ObjCIvarDecl* Ivar = (*IVI); 5348 5349 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5350 ObjCIvarDecl* prevIvar = 5351 ID->getSuperClass()->lookupInstanceVariable(II); 5352 if (prevIvar) { 5353 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5354 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5355 } 5356 } 5357 } 5358 } 5359 } else if (ObjCImplementationDecl *IMPDecl = 5360 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5361 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5362 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5363 // Ivar declared in @implementation never belongs to the implementation. 5364 // Only it is in implementation's lexical context. 5365 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5366 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5367 } 5368 } 5369 5370 if (Attr) 5371 ProcessDeclAttributeList(S, Record, Attr); 5372} 5373 5374EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5375 EnumConstantDecl *LastEnumConst, 5376 SourceLocation IdLoc, 5377 IdentifierInfo *Id, 5378 ExprArg val) { 5379 Expr *Val = (Expr *)val.get(); 5380 5381 llvm::APSInt EnumVal(32); 5382 QualType EltTy; 5383 if (Val) { 5384 if (Val->isTypeDependent()) 5385 EltTy = Context.DependentTy; 5386 else { 5387 // Make sure to promote the operand type to int. 5388 UsualUnaryConversions(Val); 5389 if (Val != val.get()) { 5390 val.release(); 5391 val = Val; 5392 } 5393 5394 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5395 SourceLocation ExpLoc; 5396 if (!Val->isValueDependent() && 5397 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5398 Val = 0; 5399 } else { 5400 EltTy = Val->getType(); 5401 } 5402 } 5403 } 5404 5405 if (!Val) { 5406 if (LastEnumConst) { 5407 // Assign the last value + 1. 5408 EnumVal = LastEnumConst->getInitVal(); 5409 ++EnumVal; 5410 5411 // Check for overflow on increment. 5412 if (EnumVal < LastEnumConst->getInitVal()) 5413 Diag(IdLoc, diag::warn_enum_value_overflow); 5414 5415 EltTy = LastEnumConst->getType(); 5416 } else { 5417 // First value, set to zero. 5418 EltTy = Context.IntTy; 5419 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5420 } 5421 } 5422 5423 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5424 5425 val.release(); 5426 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5427 Val, EnumVal); 5428} 5429 5430 5431Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5432 DeclPtrTy lastEnumConst, 5433 SourceLocation IdLoc, 5434 IdentifierInfo *Id, 5435 SourceLocation EqualLoc, ExprTy *val) { 5436 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5437 EnumConstantDecl *LastEnumConst = 5438 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5439 Expr *Val = static_cast<Expr*>(val); 5440 5441 // The scope passed in may not be a decl scope. Zip up the scope tree until 5442 // we find one that is. 5443 S = getNonFieldDeclScope(S); 5444 5445 // Verify that there isn't already something declared with this name in this 5446 // scope. 5447 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5448 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5449 // Maybe we will complain about the shadowed template parameter. 5450 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5451 // Just pretend that we didn't see the previous declaration. 5452 PrevDecl = 0; 5453 } 5454 5455 if (PrevDecl) { 5456 // When in C++, we may get a TagDecl with the same name; in this case the 5457 // enum constant will 'hide' the tag. 5458 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5459 "Received TagDecl when not in C++!"); 5460 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5461 if (isa<EnumConstantDecl>(PrevDecl)) 5462 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5463 else 5464 Diag(IdLoc, diag::err_redefinition) << Id; 5465 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5466 if (Val) Val->Destroy(Context); 5467 return DeclPtrTy(); 5468 } 5469 } 5470 5471 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5472 IdLoc, Id, Owned(Val)); 5473 5474 // Register this decl in the current scope stack. 5475 if (New) 5476 PushOnScopeChains(New, S); 5477 5478 return DeclPtrTy::make(New); 5479} 5480 5481void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5482 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5483 DeclPtrTy *Elements, unsigned NumElements, 5484 Scope *S, AttributeList *Attr) { 5485 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5486 QualType EnumType = Context.getTypeDeclType(Enum); 5487 5488 if (Attr) 5489 ProcessDeclAttributeList(S, Enum, Attr); 5490 5491 // TODO: If the result value doesn't fit in an int, it must be a long or long 5492 // long value. ISO C does not support this, but GCC does as an extension, 5493 // emit a warning. 5494 unsigned IntWidth = Context.Target.getIntWidth(); 5495 unsigned CharWidth = Context.Target.getCharWidth(); 5496 unsigned ShortWidth = Context.Target.getShortWidth(); 5497 5498 // Verify that all the values are okay, compute the size of the values, and 5499 // reverse the list. 5500 unsigned NumNegativeBits = 0; 5501 unsigned NumPositiveBits = 0; 5502 5503 // Keep track of whether all elements have type int. 5504 bool AllElementsInt = true; 5505 5506 for (unsigned i = 0; i != NumElements; ++i) { 5507 EnumConstantDecl *ECD = 5508 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5509 if (!ECD) continue; // Already issued a diagnostic. 5510 5511 // If the enum value doesn't fit in an int, emit an extension warning. 5512 const llvm::APSInt &InitVal = ECD->getInitVal(); 5513 assert(InitVal.getBitWidth() >= IntWidth && 5514 "Should have promoted value to int"); 5515 if (InitVal.getBitWidth() > IntWidth) { 5516 llvm::APSInt V(InitVal); 5517 V.trunc(IntWidth); 5518 V.extend(InitVal.getBitWidth()); 5519 if (V != InitVal) 5520 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5521 << InitVal.toString(10); 5522 } 5523 5524 // Keep track of the size of positive and negative values. 5525 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5526 NumPositiveBits = std::max(NumPositiveBits, 5527 (unsigned)InitVal.getActiveBits()); 5528 else 5529 NumNegativeBits = std::max(NumNegativeBits, 5530 (unsigned)InitVal.getMinSignedBits()); 5531 5532 // Keep track of whether every enum element has type int (very commmon). 5533 if (AllElementsInt) 5534 AllElementsInt = ECD->getType() == Context.IntTy; 5535 } 5536 5537 // Figure out the type that should be used for this enum. 5538 // FIXME: Support -fshort-enums. 5539 QualType BestType; 5540 unsigned BestWidth; 5541 5542 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5543 5544 if (NumNegativeBits) { 5545 // If there is a negative value, figure out the smallest integer type (of 5546 // int/long/longlong) that fits. 5547 // If it's packed, check also if it fits a char or a short. 5548 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5549 BestType = Context.SignedCharTy; 5550 BestWidth = CharWidth; 5551 } else if (Packed && NumNegativeBits <= ShortWidth && 5552 NumPositiveBits < ShortWidth) { 5553 BestType = Context.ShortTy; 5554 BestWidth = ShortWidth; 5555 } 5556 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5557 BestType = Context.IntTy; 5558 BestWidth = IntWidth; 5559 } else { 5560 BestWidth = Context.Target.getLongWidth(); 5561 5562 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5563 BestType = Context.LongTy; 5564 else { 5565 BestWidth = Context.Target.getLongLongWidth(); 5566 5567 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5568 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5569 BestType = Context.LongLongTy; 5570 } 5571 } 5572 } else { 5573 // If there is no negative value, figure out which of uint, ulong, ulonglong 5574 // fits. 5575 // If it's packed, check also if it fits a char or a short. 5576 if (Packed && NumPositiveBits <= CharWidth) { 5577 BestType = Context.UnsignedCharTy; 5578 BestWidth = CharWidth; 5579 } else if (Packed && NumPositiveBits <= ShortWidth) { 5580 BestType = Context.UnsignedShortTy; 5581 BestWidth = ShortWidth; 5582 } 5583 else if (NumPositiveBits <= IntWidth) { 5584 BestType = Context.UnsignedIntTy; 5585 BestWidth = IntWidth; 5586 } else if (NumPositiveBits <= 5587 (BestWidth = Context.Target.getLongWidth())) { 5588 BestType = Context.UnsignedLongTy; 5589 } else { 5590 BestWidth = Context.Target.getLongLongWidth(); 5591 assert(NumPositiveBits <= BestWidth && 5592 "How could an initializer get larger than ULL?"); 5593 BestType = Context.UnsignedLongLongTy; 5594 } 5595 } 5596 5597 // Loop over all of the enumerator constants, changing their types to match 5598 // the type of the enum if needed. 5599 for (unsigned i = 0; i != NumElements; ++i) { 5600 EnumConstantDecl *ECD = 5601 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5602 if (!ECD) continue; // Already issued a diagnostic. 5603 5604 // Standard C says the enumerators have int type, but we allow, as an 5605 // extension, the enumerators to be larger than int size. If each 5606 // enumerator value fits in an int, type it as an int, otherwise type it the 5607 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5608 // that X has type 'int', not 'unsigned'. 5609 if (ECD->getType() == Context.IntTy) { 5610 // Make sure the init value is signed. 5611 llvm::APSInt IV = ECD->getInitVal(); 5612 IV.setIsSigned(true); 5613 ECD->setInitVal(IV); 5614 5615 if (getLangOptions().CPlusPlus) 5616 // C++ [dcl.enum]p4: Following the closing brace of an 5617 // enum-specifier, each enumerator has the type of its 5618 // enumeration. 5619 ECD->setType(EnumType); 5620 continue; // Already int type. 5621 } 5622 5623 // Determine whether the value fits into an int. 5624 llvm::APSInt InitVal = ECD->getInitVal(); 5625 bool FitsInInt; 5626 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5627 FitsInInt = InitVal.getActiveBits() < IntWidth; 5628 else 5629 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5630 5631 // If it fits into an integer type, force it. Otherwise force it to match 5632 // the enum decl type. 5633 QualType NewTy; 5634 unsigned NewWidth; 5635 bool NewSign; 5636 if (FitsInInt) { 5637 NewTy = Context.IntTy; 5638 NewWidth = IntWidth; 5639 NewSign = true; 5640 } else if (ECD->getType() == BestType) { 5641 // Already the right type! 5642 if (getLangOptions().CPlusPlus) 5643 // C++ [dcl.enum]p4: Following the closing brace of an 5644 // enum-specifier, each enumerator has the type of its 5645 // enumeration. 5646 ECD->setType(EnumType); 5647 continue; 5648 } else { 5649 NewTy = BestType; 5650 NewWidth = BestWidth; 5651 NewSign = BestType->isSignedIntegerType(); 5652 } 5653 5654 // Adjust the APSInt value. 5655 InitVal.extOrTrunc(NewWidth); 5656 InitVal.setIsSigned(NewSign); 5657 ECD->setInitVal(InitVal); 5658 5659 // Adjust the Expr initializer and type. 5660 if (ECD->getInitExpr()) 5661 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5662 CastExpr::CK_IntegralCast, 5663 ECD->getInitExpr(), 5664 /*isLvalue=*/false)); 5665 if (getLangOptions().CPlusPlus) 5666 // C++ [dcl.enum]p4: Following the closing brace of an 5667 // enum-specifier, each enumerator has the type of its 5668 // enumeration. 5669 ECD->setType(EnumType); 5670 else 5671 ECD->setType(NewTy); 5672 } 5673 5674 Enum->completeDefinition(Context, BestType); 5675} 5676 5677Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5678 ExprArg expr) { 5679 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5680 5681 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5682 Loc, AsmString); 5683 CurContext->addDecl(New); 5684 return DeclPtrTy::make(New); 5685} 5686 5687void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5688 SourceLocation PragmaLoc, 5689 SourceLocation NameLoc) { 5690 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5691 5692 if (PrevDecl) { 5693 PrevDecl->addAttr(::new (Context) WeakAttr()); 5694 } else { 5695 (void)WeakUndeclaredIdentifiers.insert( 5696 std::pair<IdentifierInfo*,WeakInfo> 5697 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5698 } 5699} 5700 5701void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5702 IdentifierInfo* AliasName, 5703 SourceLocation PragmaLoc, 5704 SourceLocation NameLoc, 5705 SourceLocation AliasNameLoc) { 5706 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5707 WeakInfo W = WeakInfo(Name, NameLoc); 5708 5709 if (PrevDecl) { 5710 if (!PrevDecl->hasAttr<AliasAttr>()) 5711 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5712 DeclApplyPragmaWeak(TUScope, ND, W); 5713 } else { 5714 (void)WeakUndeclaredIdentifiers.insert( 5715 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5716 } 5717} 5718