SemaDecl.cpp revision cd6cdeb7d15af731d1d06d9aee4190713f59e8d7
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 } 135 136 case LookupResult::Found: 137 IIDecl = Result.getFoundDecl(); 138 break; 139 } 140 141 if (IIDecl) { 142 QualType T; 143 144 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 145 // Check whether we can use this type 146 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 147 148 if (getLangOptions().CPlusPlus) { 149 // C++ [temp.local]p2: 150 // Within the scope of a class template specialization or 151 // partial specialization, when the injected-class-name is 152 // not followed by a <, it is equivalent to the 153 // injected-class-name followed by the template-argument s 154 // of the class template specialization or partial 155 // specialization enclosed in <>. 156 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 157 if (RD->isInjectedClassName()) 158 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 159 T = Template->getInjectedClassNameType(Context); 160 } 161 162 if (T.isNull()) 163 T = Context.getTypeDeclType(TD); 164 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 165 // Check whether we can use this interface. 166 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 167 168 T = Context.getObjCInterfaceType(IDecl); 169 } else 170 return 0; 171 172 if (SS) 173 T = getQualifiedNameType(*SS, T); 174 175 return T.getAsOpaquePtr(); 176 } 177 178 return 0; 179} 180 181/// isTagName() - This method is called *for error recovery purposes only* 182/// to determine if the specified name is a valid tag name ("struct foo"). If 183/// so, this returns the TST for the tag corresponding to it (TST_enum, 184/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 185/// where the user forgot to specify the tag. 186DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 187 // Do a tag name lookup in this scope. 188 LookupResult R; 189 LookupName(R, S, &II, LookupTagName, false, false); 190 if (R.getKind() == LookupResult::Found) 191 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 192 switch (TD->getTagKind()) { 193 case TagDecl::TK_struct: return DeclSpec::TST_struct; 194 case TagDecl::TK_union: return DeclSpec::TST_union; 195 case TagDecl::TK_class: return DeclSpec::TST_class; 196 case TagDecl::TK_enum: return DeclSpec::TST_enum; 197 } 198 } 199 200 return DeclSpec::TST_unspecified; 201} 202 203bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 204 SourceLocation IILoc, 205 Scope *S, 206 const CXXScopeSpec *SS, 207 TypeTy *&SuggestedType) { 208 // We don't have anything to suggest (yet). 209 SuggestedType = 0; 210 211 // FIXME: Should we move the logic that tries to recover from a missing tag 212 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 213 214 if (!SS) 215 Diag(IILoc, diag::err_unknown_typename) << &II; 216 else if (DeclContext *DC = computeDeclContext(*SS, false)) 217 Diag(IILoc, diag::err_typename_nested_not_found) 218 << &II << DC << SS->getRange(); 219 else if (isDependentScopeSpecifier(*SS)) { 220 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 221 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 222 << SourceRange(SS->getRange().getBegin(), IILoc) 223 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 224 "typename "); 225 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 226 } else { 227 assert(SS && SS->isInvalid() && 228 "Invalid scope specifier has already been diagnosed"); 229 } 230 231 return true; 232} 233 234// Determines the context to return to after temporarily entering a 235// context. This depends in an unnecessarily complicated way on the 236// exact ordering of callbacks from the parser. 237DeclContext *Sema::getContainingDC(DeclContext *DC) { 238 239 // Functions defined inline within classes aren't parsed until we've 240 // finished parsing the top-level class, so the top-level class is 241 // the context we'll need to return to. 242 if (isa<FunctionDecl>(DC)) { 243 DC = DC->getLexicalParent(); 244 245 // A function not defined within a class will always return to its 246 // lexical context. 247 if (!isa<CXXRecordDecl>(DC)) 248 return DC; 249 250 // A C++ inline method/friend is parsed *after* the topmost class 251 // it was declared in is fully parsed ("complete"); the topmost 252 // class is the context we need to return to. 253 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 254 DC = RD; 255 256 // Return the declaration context of the topmost class the inline method is 257 // declared in. 258 return DC; 259 } 260 261 if (isa<ObjCMethodDecl>(DC)) 262 return Context.getTranslationUnitDecl(); 263 264 return DC->getLexicalParent(); 265} 266 267void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 268 assert(getContainingDC(DC) == CurContext && 269 "The next DeclContext should be lexically contained in the current one."); 270 CurContext = DC; 271 S->setEntity(DC); 272} 273 274void Sema::PopDeclContext() { 275 assert(CurContext && "DeclContext imbalance!"); 276 277 CurContext = getContainingDC(CurContext); 278} 279 280/// EnterDeclaratorContext - Used when we must lookup names in the context 281/// of a declarator's nested name specifier. 282void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 283 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 284 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 285 CurContext = DC; 286 assert(CurContext && "No context?"); 287 S->setEntity(CurContext); 288} 289 290void Sema::ExitDeclaratorContext(Scope *S) { 291 S->setEntity(PreDeclaratorDC); 292 PreDeclaratorDC = 0; 293 294 // Reset CurContext to the nearest enclosing context. 295 while (!S->getEntity() && S->getParent()) 296 S = S->getParent(); 297 CurContext = static_cast<DeclContext*>(S->getEntity()); 298 assert(CurContext && "No context?"); 299} 300 301/// \brief Determine whether we allow overloading of the function 302/// PrevDecl with another declaration. 303/// 304/// This routine determines whether overloading is possible, not 305/// whether some new function is actually an overload. It will return 306/// true in C++ (where we can always provide overloads) or, as an 307/// extension, in C when the previous function is already an 308/// overloaded function declaration or has the "overloadable" 309/// attribute. 310static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 311 if (Context.getLangOptions().CPlusPlus) 312 return true; 313 314 if (isa<OverloadedFunctionDecl>(PrevDecl)) 315 return true; 316 317 return PrevDecl->getAttr<OverloadableAttr>() != 0; 318} 319 320/// Add this decl to the scope shadowed decl chains. 321void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 322 // Move up the scope chain until we find the nearest enclosing 323 // non-transparent context. The declaration will be introduced into this 324 // scope. 325 while (S->getEntity() && 326 ((DeclContext *)S->getEntity())->isTransparentContext()) 327 S = S->getParent(); 328 329 // Add scoped declarations into their context, so that they can be 330 // found later. Declarations without a context won't be inserted 331 // into any context. 332 if (AddToContext) 333 CurContext->addDecl(D); 334 335 // Out-of-line function and variable definitions should not be pushed into 336 // scope. 337 if ((isa<FunctionTemplateDecl>(D) && 338 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 339 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 340 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 341 return; 342 343 // If this replaces anything in the current scope, 344 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 345 IEnd = IdResolver.end(); 346 for (; I != IEnd; ++I) { 347 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 348 S->RemoveDecl(DeclPtrTy::make(*I)); 349 IdResolver.RemoveDecl(*I); 350 351 // Should only need to replace one decl. 352 break; 353 } 354 } 355 356 S->AddDecl(DeclPtrTy::make(D)); 357 IdResolver.AddDecl(D); 358} 359 360bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 361 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 362 // Look inside the overload set to determine if any of the declarations 363 // are in scope. (Possibly) build a new overload set containing only 364 // those declarations that are in scope. 365 OverloadedFunctionDecl *NewOvl = 0; 366 bool FoundInScope = false; 367 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 368 FEnd = Ovl->function_end(); 369 F != FEnd; ++F) { 370 NamedDecl *FD = F->get(); 371 if (!isDeclInScope(FD, Ctx, S)) { 372 if (!NewOvl && F != Ovl->function_begin()) { 373 NewOvl = OverloadedFunctionDecl::Create(Context, 374 F->get()->getDeclContext(), 375 F->get()->getDeclName()); 376 D = NewOvl; 377 for (OverloadedFunctionDecl::function_iterator 378 First = Ovl->function_begin(); 379 First != F; ++First) 380 NewOvl->addOverload(*First); 381 } 382 } else { 383 FoundInScope = true; 384 if (NewOvl) 385 NewOvl->addOverload(*F); 386 } 387 } 388 389 return FoundInScope; 390 } 391 392 return IdResolver.isDeclInScope(D, Ctx, Context, S); 393} 394 395void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 396 if (S->decl_empty()) return; 397 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 398 "Scope shouldn't contain decls!"); 399 400 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 401 I != E; ++I) { 402 Decl *TmpD = (*I).getAs<Decl>(); 403 assert(TmpD && "This decl didn't get pushed??"); 404 405 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 406 NamedDecl *D = cast<NamedDecl>(TmpD); 407 408 if (!D->getDeclName()) continue; 409 410 // Diagnose unused variables in this scope. 411 if (!D->isUsed() && !D->hasAttr<UnusedAttr>() && isa<VarDecl>(D) && 412 !isa<ParmVarDecl>(D) && !isa<ImplicitParamDecl>(D) && 413 D->getDeclContext()->isFunctionOrMethod()) 414 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 415 416 // Remove this name from our lexical scope. 417 IdResolver.RemoveDecl(D); 418 } 419} 420 421/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 422/// return 0 if one not found. 423ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 424 // The third "scope" argument is 0 since we aren't enabling lazy built-in 425 // creation from this context. 426 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 427 428 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 429} 430 431/// getNonFieldDeclScope - Retrieves the innermost scope, starting 432/// from S, where a non-field would be declared. This routine copes 433/// with the difference between C and C++ scoping rules in structs and 434/// unions. For example, the following code is well-formed in C but 435/// ill-formed in C++: 436/// @code 437/// struct S6 { 438/// enum { BAR } e; 439/// }; 440/// 441/// void test_S6() { 442/// struct S6 a; 443/// a.e = BAR; 444/// } 445/// @endcode 446/// For the declaration of BAR, this routine will return a different 447/// scope. The scope S will be the scope of the unnamed enumeration 448/// within S6. In C++, this routine will return the scope associated 449/// with S6, because the enumeration's scope is a transparent 450/// context but structures can contain non-field names. In C, this 451/// routine will return the translation unit scope, since the 452/// enumeration's scope is a transparent context and structures cannot 453/// contain non-field names. 454Scope *Sema::getNonFieldDeclScope(Scope *S) { 455 while (((S->getFlags() & Scope::DeclScope) == 0) || 456 (S->getEntity() && 457 ((DeclContext *)S->getEntity())->isTransparentContext()) || 458 (S->isClassScope() && !getLangOptions().CPlusPlus)) 459 S = S->getParent(); 460 return S; 461} 462 463void Sema::InitBuiltinVaListType() { 464 if (!Context.getBuiltinVaListType().isNull()) 465 return; 466 467 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 468 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 469 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 470 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 471} 472 473/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 474/// file scope. lazily create a decl for it. ForRedeclaration is true 475/// if we're creating this built-in in anticipation of redeclaring the 476/// built-in. 477NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 478 Scope *S, bool ForRedeclaration, 479 SourceLocation Loc) { 480 Builtin::ID BID = (Builtin::ID)bid; 481 482 if (Context.BuiltinInfo.hasVAListUse(BID)) 483 InitBuiltinVaListType(); 484 485 ASTContext::GetBuiltinTypeError Error; 486 QualType R = Context.GetBuiltinType(BID, Error); 487 switch (Error) { 488 case ASTContext::GE_None: 489 // Okay 490 break; 491 492 case ASTContext::GE_Missing_stdio: 493 if (ForRedeclaration) 494 Diag(Loc, diag::err_implicit_decl_requires_stdio) 495 << Context.BuiltinInfo.GetName(BID); 496 return 0; 497 498 case ASTContext::GE_Missing_setjmp: 499 if (ForRedeclaration) 500 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 501 << Context.BuiltinInfo.GetName(BID); 502 return 0; 503 } 504 505 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 506 Diag(Loc, diag::ext_implicit_lib_function_decl) 507 << Context.BuiltinInfo.GetName(BID) 508 << R; 509 if (Context.BuiltinInfo.getHeaderName(BID) && 510 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 511 != Diagnostic::Ignored) 512 Diag(Loc, diag::note_please_include_header) 513 << Context.BuiltinInfo.getHeaderName(BID) 514 << Context.BuiltinInfo.GetName(BID); 515 } 516 517 FunctionDecl *New = FunctionDecl::Create(Context, 518 Context.getTranslationUnitDecl(), 519 Loc, II, R, /*DInfo=*/0, 520 FunctionDecl::Extern, false, 521 /*hasPrototype=*/true); 522 New->setImplicit(); 523 524 // Create Decl objects for each parameter, adding them to the 525 // FunctionDecl. 526 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 527 llvm::SmallVector<ParmVarDecl*, 16> Params; 528 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 529 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 530 FT->getArgType(i), /*DInfo=*/0, 531 VarDecl::None, 0)); 532 New->setParams(Context, Params.data(), Params.size()); 533 } 534 535 AddKnownFunctionAttributes(New); 536 537 // TUScope is the translation-unit scope to insert this function into. 538 // FIXME: This is hideous. We need to teach PushOnScopeChains to 539 // relate Scopes to DeclContexts, and probably eliminate CurContext 540 // entirely, but we're not there yet. 541 DeclContext *SavedContext = CurContext; 542 CurContext = Context.getTranslationUnitDecl(); 543 PushOnScopeChains(New, TUScope); 544 CurContext = SavedContext; 545 return New; 546} 547 548/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 549/// same name and scope as a previous declaration 'Old'. Figure out 550/// how to resolve this situation, merging decls or emitting 551/// diagnostics as appropriate. If there was an error, set New to be invalid. 552/// 553void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 554 // If either decl is known invalid already, set the new one to be invalid and 555 // don't bother doing any merging checks. 556 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 557 return New->setInvalidDecl(); 558 559 // Allow multiple definitions for ObjC built-in typedefs. 560 // FIXME: Verify the underlying types are equivalent! 561 if (getLangOptions().ObjC1) { 562 const IdentifierInfo *TypeID = New->getIdentifier(); 563 switch (TypeID->getLength()) { 564 default: break; 565 case 2: 566 if (!TypeID->isStr("id")) 567 break; 568 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 569 // Install the built-in type for 'id', ignoring the current definition. 570 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 571 return; 572 case 5: 573 if (!TypeID->isStr("Class")) 574 break; 575 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 576 // Install the built-in type for 'Class', ignoring the current definition. 577 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 578 return; 579 case 3: 580 if (!TypeID->isStr("SEL")) 581 break; 582 Context.setObjCSelType(Context.getTypeDeclType(New)); 583 return; 584 case 8: 585 if (!TypeID->isStr("Protocol")) 586 break; 587 Context.setObjCProtoType(New->getUnderlyingType()); 588 return; 589 } 590 // Fall through - the typedef name was not a builtin type. 591 } 592 // Verify the old decl was also a type. 593 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 594 if (!Old) { 595 Diag(New->getLocation(), diag::err_redefinition_different_kind) 596 << New->getDeclName(); 597 if (OldD->getLocation().isValid()) 598 Diag(OldD->getLocation(), diag::note_previous_definition); 599 return New->setInvalidDecl(); 600 } 601 602 // Determine the "old" type we'll use for checking and diagnostics. 603 QualType OldType; 604 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 605 OldType = OldTypedef->getUnderlyingType(); 606 else 607 OldType = Context.getTypeDeclType(Old); 608 609 // If the typedef types are not identical, reject them in all languages and 610 // with any extensions enabled. 611 612 if (OldType != New->getUnderlyingType() && 613 Context.getCanonicalType(OldType) != 614 Context.getCanonicalType(New->getUnderlyingType())) { 615 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 616 << New->getUnderlyingType() << OldType; 617 if (Old->getLocation().isValid()) 618 Diag(Old->getLocation(), diag::note_previous_definition); 619 return New->setInvalidDecl(); 620 } 621 622 if (getLangOptions().Microsoft) 623 return; 624 625 // C++ [dcl.typedef]p2: 626 // In a given non-class scope, a typedef specifier can be used to 627 // redefine the name of any type declared in that scope to refer 628 // to the type to which it already refers. 629 if (getLangOptions().CPlusPlus) { 630 if (!isa<CXXRecordDecl>(CurContext)) 631 return; 632 Diag(New->getLocation(), diag::err_redefinition) 633 << New->getDeclName(); 634 Diag(Old->getLocation(), diag::note_previous_definition); 635 return New->setInvalidDecl(); 636 } 637 638 // If we have a redefinition of a typedef in C, emit a warning. This warning 639 // is normally mapped to an error, but can be controlled with 640 // -Wtypedef-redefinition. If either the original or the redefinition is 641 // in a system header, don't emit this for compatibility with GCC. 642 if (PP.getDiagnostics().getSuppressSystemWarnings() && 643 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 644 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 645 return; 646 647 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 648 << New->getDeclName(); 649 Diag(Old->getLocation(), diag::note_previous_definition); 650 return; 651} 652 653/// DeclhasAttr - returns true if decl Declaration already has the target 654/// attribute. 655static bool 656DeclHasAttr(const Decl *decl, const Attr *target) { 657 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 658 if (attr->getKind() == target->getKind()) 659 return true; 660 661 return false; 662} 663 664/// MergeAttributes - append attributes from the Old decl to the New one. 665static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 666 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 667 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 668 Attr *NewAttr = attr->clone(C); 669 NewAttr->setInherited(true); 670 New->addAttr(NewAttr); 671 } 672 } 673} 674 675/// Used in MergeFunctionDecl to keep track of function parameters in 676/// C. 677struct GNUCompatibleParamWarning { 678 ParmVarDecl *OldParm; 679 ParmVarDecl *NewParm; 680 QualType PromotedType; 681}; 682 683/// MergeFunctionDecl - We just parsed a function 'New' from 684/// declarator D which has the same name and scope as a previous 685/// declaration 'Old'. Figure out how to resolve this situation, 686/// merging decls or emitting diagnostics as appropriate. 687/// 688/// In C++, New and Old must be declarations that are not 689/// overloaded. Use IsOverload to determine whether New and Old are 690/// overloaded, and to select the Old declaration that New should be 691/// merged with. 692/// 693/// Returns true if there was an error, false otherwise. 694bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 695 assert(!isa<OverloadedFunctionDecl>(OldD) && 696 "Cannot merge with an overloaded function declaration"); 697 698 // Verify the old decl was also a function. 699 FunctionDecl *Old = 0; 700 if (FunctionTemplateDecl *OldFunctionTemplate 701 = dyn_cast<FunctionTemplateDecl>(OldD)) 702 Old = OldFunctionTemplate->getTemplatedDecl(); 703 else 704 Old = dyn_cast<FunctionDecl>(OldD); 705 if (!Old) { 706 Diag(New->getLocation(), diag::err_redefinition_different_kind) 707 << New->getDeclName(); 708 Diag(OldD->getLocation(), diag::note_previous_definition); 709 return true; 710 } 711 712 // Determine whether the previous declaration was a definition, 713 // implicit declaration, or a declaration. 714 diag::kind PrevDiag; 715 if (Old->isThisDeclarationADefinition()) 716 PrevDiag = diag::note_previous_definition; 717 else if (Old->isImplicit()) 718 PrevDiag = diag::note_previous_implicit_declaration; 719 else 720 PrevDiag = diag::note_previous_declaration; 721 722 QualType OldQType = Context.getCanonicalType(Old->getType()); 723 QualType NewQType = Context.getCanonicalType(New->getType()); 724 725 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 726 New->getStorageClass() == FunctionDecl::Static && 727 Old->getStorageClass() != FunctionDecl::Static) { 728 Diag(New->getLocation(), diag::err_static_non_static) 729 << New; 730 Diag(Old->getLocation(), PrevDiag); 731 return true; 732 } 733 734 if (getLangOptions().CPlusPlus) { 735 // (C++98 13.1p2): 736 // Certain function declarations cannot be overloaded: 737 // -- Function declarations that differ only in the return type 738 // cannot be overloaded. 739 QualType OldReturnType 740 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 741 QualType NewReturnType 742 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 743 if (OldReturnType != NewReturnType) { 744 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 745 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 746 return true; 747 } 748 749 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 750 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 751 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 752 NewMethod->getLexicalDeclContext()->isRecord()) { 753 // -- Member function declarations with the same name and the 754 // same parameter types cannot be overloaded if any of them 755 // is a static member function declaration. 756 if (OldMethod->isStatic() || NewMethod->isStatic()) { 757 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 758 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 759 return true; 760 } 761 762 // C++ [class.mem]p1: 763 // [...] A member shall not be declared twice in the 764 // member-specification, except that a nested class or member 765 // class template can be declared and then later defined. 766 unsigned NewDiag; 767 if (isa<CXXConstructorDecl>(OldMethod)) 768 NewDiag = diag::err_constructor_redeclared; 769 else if (isa<CXXDestructorDecl>(NewMethod)) 770 NewDiag = diag::err_destructor_redeclared; 771 else if (isa<CXXConversionDecl>(NewMethod)) 772 NewDiag = diag::err_conv_function_redeclared; 773 else 774 NewDiag = diag::err_member_redeclared; 775 776 Diag(New->getLocation(), NewDiag); 777 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 778 } 779 780 // (C++98 8.3.5p3): 781 // All declarations for a function shall agree exactly in both the 782 // return type and the parameter-type-list. 783 if (OldQType == NewQType) 784 return MergeCompatibleFunctionDecls(New, Old); 785 786 // Fall through for conflicting redeclarations and redefinitions. 787 } 788 789 // C: Function types need to be compatible, not identical. This handles 790 // duplicate function decls like "void f(int); void f(enum X);" properly. 791 if (!getLangOptions().CPlusPlus && 792 Context.typesAreCompatible(OldQType, NewQType)) { 793 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 794 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 795 const FunctionProtoType *OldProto = 0; 796 if (isa<FunctionNoProtoType>(NewFuncType) && 797 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 798 // The old declaration provided a function prototype, but the 799 // new declaration does not. Merge in the prototype. 800 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 801 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 802 OldProto->arg_type_end()); 803 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 804 ParamTypes.data(), ParamTypes.size(), 805 OldProto->isVariadic(), 806 OldProto->getTypeQuals()); 807 New->setType(NewQType); 808 New->setHasInheritedPrototype(); 809 810 // Synthesize a parameter for each argument type. 811 llvm::SmallVector<ParmVarDecl*, 16> Params; 812 for (FunctionProtoType::arg_type_iterator 813 ParamType = OldProto->arg_type_begin(), 814 ParamEnd = OldProto->arg_type_end(); 815 ParamType != ParamEnd; ++ParamType) { 816 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 817 SourceLocation(), 0, 818 *ParamType, /*DInfo=*/0, 819 VarDecl::None, 0); 820 Param->setImplicit(); 821 Params.push_back(Param); 822 } 823 824 New->setParams(Context, Params.data(), Params.size()); 825 } 826 827 return MergeCompatibleFunctionDecls(New, Old); 828 } 829 830 // GNU C permits a K&R definition to follow a prototype declaration 831 // if the declared types of the parameters in the K&R definition 832 // match the types in the prototype declaration, even when the 833 // promoted types of the parameters from the K&R definition differ 834 // from the types in the prototype. GCC then keeps the types from 835 // the prototype. 836 // 837 // If a variadic prototype is followed by a non-variadic K&R definition, 838 // the K&R definition becomes variadic. This is sort of an edge case, but 839 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 840 // C99 6.9.1p8. 841 if (!getLangOptions().CPlusPlus && 842 Old->hasPrototype() && !New->hasPrototype() && 843 New->getType()->getAs<FunctionProtoType>() && 844 Old->getNumParams() == New->getNumParams()) { 845 llvm::SmallVector<QualType, 16> ArgTypes; 846 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 847 const FunctionProtoType *OldProto 848 = Old->getType()->getAs<FunctionProtoType>(); 849 const FunctionProtoType *NewProto 850 = New->getType()->getAs<FunctionProtoType>(); 851 852 // Determine whether this is the GNU C extension. 853 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 854 NewProto->getResultType()); 855 bool LooseCompatible = !MergedReturn.isNull(); 856 for (unsigned Idx = 0, End = Old->getNumParams(); 857 LooseCompatible && Idx != End; ++Idx) { 858 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 859 ParmVarDecl *NewParm = New->getParamDecl(Idx); 860 if (Context.typesAreCompatible(OldParm->getType(), 861 NewProto->getArgType(Idx))) { 862 ArgTypes.push_back(NewParm->getType()); 863 } else if (Context.typesAreCompatible(OldParm->getType(), 864 NewParm->getType())) { 865 GNUCompatibleParamWarning Warn 866 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 867 Warnings.push_back(Warn); 868 ArgTypes.push_back(NewParm->getType()); 869 } else 870 LooseCompatible = false; 871 } 872 873 if (LooseCompatible) { 874 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 875 Diag(Warnings[Warn].NewParm->getLocation(), 876 diag::ext_param_promoted_not_compatible_with_prototype) 877 << Warnings[Warn].PromotedType 878 << Warnings[Warn].OldParm->getType(); 879 Diag(Warnings[Warn].OldParm->getLocation(), 880 diag::note_previous_declaration); 881 } 882 883 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 884 ArgTypes.size(), 885 OldProto->isVariadic(), 0)); 886 return MergeCompatibleFunctionDecls(New, Old); 887 } 888 889 // Fall through to diagnose conflicting types. 890 } 891 892 // A function that has already been declared has been redeclared or defined 893 // with a different type- show appropriate diagnostic 894 if (unsigned BuiltinID = Old->getBuiltinID()) { 895 // The user has declared a builtin function with an incompatible 896 // signature. 897 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 898 // The function the user is redeclaring is a library-defined 899 // function like 'malloc' or 'printf'. Warn about the 900 // redeclaration, then pretend that we don't know about this 901 // library built-in. 902 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 903 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 904 << Old << Old->getType(); 905 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 906 Old->setInvalidDecl(); 907 return false; 908 } 909 910 PrevDiag = diag::note_previous_builtin_declaration; 911 } 912 913 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 914 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 915 return true; 916} 917 918/// \brief Completes the merge of two function declarations that are 919/// known to be compatible. 920/// 921/// This routine handles the merging of attributes and other 922/// properties of function declarations form the old declaration to 923/// the new declaration, once we know that New is in fact a 924/// redeclaration of Old. 925/// 926/// \returns false 927bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 928 // Merge the attributes 929 MergeAttributes(New, Old, Context); 930 931 // Merge the storage class. 932 if (Old->getStorageClass() != FunctionDecl::Extern && 933 Old->getStorageClass() != FunctionDecl::None) 934 New->setStorageClass(Old->getStorageClass()); 935 936 // Merge "pure" flag. 937 if (Old->isPure()) 938 New->setPure(); 939 940 // Merge the "deleted" flag. 941 if (Old->isDeleted()) 942 New->setDeleted(); 943 944 if (getLangOptions().CPlusPlus) 945 return MergeCXXFunctionDecl(New, Old); 946 947 return false; 948} 949 950/// MergeVarDecl - We just parsed a variable 'New' which has the same name 951/// and scope as a previous declaration 'Old'. Figure out how to resolve this 952/// situation, merging decls or emitting diagnostics as appropriate. 953/// 954/// Tentative definition rules (C99 6.9.2p2) are checked by 955/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 956/// definitions here, since the initializer hasn't been attached. 957/// 958void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 959 // If either decl is invalid, make sure the new one is marked invalid and 960 // don't do any other checking. 961 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 962 return New->setInvalidDecl(); 963 964 // Verify the old decl was also a variable. 965 VarDecl *Old = dyn_cast<VarDecl>(OldD); 966 if (!Old) { 967 Diag(New->getLocation(), diag::err_redefinition_different_kind) 968 << New->getDeclName(); 969 Diag(OldD->getLocation(), diag::note_previous_definition); 970 return New->setInvalidDecl(); 971 } 972 973 MergeAttributes(New, Old, Context); 974 975 // Merge the types 976 QualType MergedT; 977 if (getLangOptions().CPlusPlus) { 978 if (Context.hasSameType(New->getType(), Old->getType())) 979 MergedT = New->getType(); 980 // C++ [basic.types]p7: 981 // [...] The declared type of an array object might be an array of 982 // unknown size and therefore be incomplete at one point in a 983 // translation unit and complete later on; [...] 984 else if (Old->getType()->isIncompleteArrayType() && 985 New->getType()->isArrayType()) { 986 CanQual<ArrayType> OldArray 987 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 988 CanQual<ArrayType> NewArray 989 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 990 if (OldArray->getElementType() == NewArray->getElementType()) 991 MergedT = New->getType(); 992 } 993 } else { 994 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 995 } 996 if (MergedT.isNull()) { 997 Diag(New->getLocation(), diag::err_redefinition_different_type) 998 << New->getDeclName(); 999 Diag(Old->getLocation(), diag::note_previous_definition); 1000 return New->setInvalidDecl(); 1001 } 1002 New->setType(MergedT); 1003 1004 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1005 if (New->getStorageClass() == VarDecl::Static && 1006 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1007 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1008 Diag(Old->getLocation(), diag::note_previous_definition); 1009 return New->setInvalidDecl(); 1010 } 1011 // C99 6.2.2p4: 1012 // For an identifier declared with the storage-class specifier 1013 // extern in a scope in which a prior declaration of that 1014 // identifier is visible,23) if the prior declaration specifies 1015 // internal or external linkage, the linkage of the identifier at 1016 // the later declaration is the same as the linkage specified at 1017 // the prior declaration. If no prior declaration is visible, or 1018 // if the prior declaration specifies no linkage, then the 1019 // identifier has external linkage. 1020 if (New->hasExternalStorage() && Old->hasLinkage()) 1021 /* Okay */; 1022 else if (New->getStorageClass() != VarDecl::Static && 1023 Old->getStorageClass() == VarDecl::Static) { 1024 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1025 Diag(Old->getLocation(), diag::note_previous_definition); 1026 return New->setInvalidDecl(); 1027 } 1028 1029 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1030 1031 // FIXME: The test for external storage here seems wrong? We still 1032 // need to check for mismatches. 1033 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1034 // Don't complain about out-of-line definitions of static members. 1035 !(Old->getLexicalDeclContext()->isRecord() && 1036 !New->getLexicalDeclContext()->isRecord())) { 1037 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1038 Diag(Old->getLocation(), diag::note_previous_definition); 1039 return New->setInvalidDecl(); 1040 } 1041 1042 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1043 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1044 Diag(Old->getLocation(), diag::note_previous_definition); 1045 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1046 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1047 Diag(Old->getLocation(), diag::note_previous_definition); 1048 } 1049 1050 // Keep a chain of previous declarations. 1051 New->setPreviousDeclaration(Old); 1052} 1053 1054/// CheckFallThrough - Check that we don't fall off the end of a 1055/// Statement that should return a value. 1056/// 1057/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1058/// MaybeFallThrough iff we might or might not fall off the end and 1059/// NeverFallThrough iff we never fall off the end of the statement. We assume 1060/// that functions not marked noreturn will return. 1061Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1062 // FIXME: Eventually share this CFG object when we have other warnings based 1063 // of the CFG. This can be done using AnalysisContext. 1064 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1065 1066 // FIXME: They should never return 0, fix that, delete this code. 1067 if (cfg == 0) 1068 return NeverFallThrough; 1069 // The CFG leaves in dead things, and we don't want to dead code paths to 1070 // confuse us, so we mark all live things first. 1071 std::queue<CFGBlock*> workq; 1072 llvm::BitVector live(cfg->getNumBlockIDs()); 1073 // Prep work queue 1074 workq.push(&cfg->getEntry()); 1075 // Solve 1076 while (!workq.empty()) { 1077 CFGBlock *item = workq.front(); 1078 workq.pop(); 1079 live.set(item->getBlockID()); 1080 for (CFGBlock::succ_iterator I=item->succ_begin(), 1081 E=item->succ_end(); 1082 I != E; 1083 ++I) { 1084 if ((*I) && !live[(*I)->getBlockID()]) { 1085 live.set((*I)->getBlockID()); 1086 workq.push(*I); 1087 } 1088 } 1089 } 1090 1091 // Now we know what is live, we check the live precessors of the exit block 1092 // and look for fall through paths, being careful to ignore normal returns, 1093 // and exceptional paths. 1094 bool HasLiveReturn = false; 1095 bool HasFakeEdge = false; 1096 bool HasPlainEdge = false; 1097 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1098 E = cfg->getExit().pred_end(); 1099 I != E; 1100 ++I) { 1101 CFGBlock& B = **I; 1102 if (!live[B.getBlockID()]) 1103 continue; 1104 if (B.size() == 0) { 1105 // A labeled empty statement, or the entry block... 1106 HasPlainEdge = true; 1107 continue; 1108 } 1109 Stmt *S = B[B.size()-1]; 1110 if (isa<ReturnStmt>(S)) { 1111 HasLiveReturn = true; 1112 continue; 1113 } 1114 if (isa<ObjCAtThrowStmt>(S)) { 1115 HasFakeEdge = true; 1116 continue; 1117 } 1118 if (isa<CXXThrowExpr>(S)) { 1119 HasFakeEdge = true; 1120 continue; 1121 } 1122 bool NoReturnEdge = false; 1123 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1124 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1125 if (CEE->getType().getNoReturnAttr()) { 1126 NoReturnEdge = true; 1127 HasFakeEdge = true; 1128 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1129 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1130 if (FD->hasAttr<NoReturnAttr>()) { 1131 NoReturnEdge = true; 1132 HasFakeEdge = true; 1133 } 1134 } 1135 } 1136 } 1137 // FIXME: Add noreturn message sends. 1138 if (NoReturnEdge == false) 1139 HasPlainEdge = true; 1140 } 1141 if (!HasPlainEdge) 1142 return NeverFallThrough; 1143 if (HasFakeEdge || HasLiveReturn) 1144 return MaybeFallThrough; 1145 // This says AlwaysFallThrough for calls to functions that are not marked 1146 // noreturn, that don't return. If people would like this warning to be more 1147 // accurate, such functions should be marked as noreturn. 1148 return AlwaysFallThrough; 1149} 1150 1151/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1152/// function that should return a value. Check that we don't fall off the end 1153/// of a noreturn function. We assume that functions and blocks not marked 1154/// noreturn will return. 1155void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1156 // FIXME: Would be nice if we had a better way to control cascading errors, 1157 // but for now, avoid them. The problem is that when Parse sees: 1158 // int foo() { return a; } 1159 // The return is eaten and the Sema code sees just: 1160 // int foo() { } 1161 // which this code would then warn about. 1162 if (getDiagnostics().hasErrorOccurred()) 1163 return; 1164 bool ReturnsVoid = false; 1165 bool HasNoReturn = false; 1166 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1167 // If the result type of the function is a dependent type, we don't know 1168 // whether it will be void or not, so don't 1169 if (FD->getResultType()->isDependentType()) 1170 return; 1171 if (FD->getResultType()->isVoidType()) 1172 ReturnsVoid = true; 1173 if (FD->hasAttr<NoReturnAttr>()) 1174 HasNoReturn = true; 1175 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1176 if (MD->getResultType()->isVoidType()) 1177 ReturnsVoid = true; 1178 if (MD->hasAttr<NoReturnAttr>()) 1179 HasNoReturn = true; 1180 } 1181 1182 // Short circuit for compilation speed. 1183 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1184 == Diagnostic::Ignored || ReturnsVoid) 1185 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1186 == Diagnostic::Ignored || !HasNoReturn) 1187 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1188 == Diagnostic::Ignored || !ReturnsVoid)) 1189 return; 1190 // FIXME: Function try block 1191 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1192 switch (CheckFallThrough(Body)) { 1193 case MaybeFallThrough: 1194 if (HasNoReturn) 1195 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1196 else if (!ReturnsVoid) 1197 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1198 break; 1199 case AlwaysFallThrough: 1200 if (HasNoReturn) 1201 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1202 else if (!ReturnsVoid) 1203 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1204 break; 1205 case NeverFallThrough: 1206 if (ReturnsVoid) 1207 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1208 break; 1209 } 1210 } 1211} 1212 1213/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1214/// that should return a value. Check that we don't fall off the end of a 1215/// noreturn block. We assume that functions and blocks not marked noreturn 1216/// will return. 1217void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1218 // FIXME: Would be nice if we had a better way to control cascading errors, 1219 // but for now, avoid them. The problem is that when Parse sees: 1220 // int foo() { return a; } 1221 // The return is eaten and the Sema code sees just: 1222 // int foo() { } 1223 // which this code would then warn about. 1224 if (getDiagnostics().hasErrorOccurred()) 1225 return; 1226 bool ReturnsVoid = false; 1227 bool HasNoReturn = false; 1228 if (const FunctionType *FT = BlockTy->getPointeeType()->getAs<FunctionType>()) { 1229 if (FT->getResultType()->isVoidType()) 1230 ReturnsVoid = true; 1231 if (FT->getNoReturnAttr()) 1232 HasNoReturn = true; 1233 } 1234 1235 // Short circuit for compilation speed. 1236 if (ReturnsVoid 1237 && !HasNoReturn 1238 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1239 == Diagnostic::Ignored || !ReturnsVoid)) 1240 return; 1241 // FIXME: Funtion try block 1242 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1243 switch (CheckFallThrough(Body)) { 1244 case MaybeFallThrough: 1245 if (HasNoReturn) 1246 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1247 else if (!ReturnsVoid) 1248 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1249 break; 1250 case AlwaysFallThrough: 1251 if (HasNoReturn) 1252 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1253 else if (!ReturnsVoid) 1254 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1255 break; 1256 case NeverFallThrough: 1257 if (ReturnsVoid) 1258 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1259 break; 1260 } 1261 } 1262} 1263 1264/// CheckParmsForFunctionDef - Check that the parameters of the given 1265/// function are appropriate for the definition of a function. This 1266/// takes care of any checks that cannot be performed on the 1267/// declaration itself, e.g., that the types of each of the function 1268/// parameters are complete. 1269bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1270 bool HasInvalidParm = false; 1271 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1272 ParmVarDecl *Param = FD->getParamDecl(p); 1273 1274 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1275 // function declarator that is part of a function definition of 1276 // that function shall not have incomplete type. 1277 // 1278 // This is also C++ [dcl.fct]p6. 1279 if (!Param->isInvalidDecl() && 1280 RequireCompleteType(Param->getLocation(), Param->getType(), 1281 diag::err_typecheck_decl_incomplete_type)) { 1282 Param->setInvalidDecl(); 1283 HasInvalidParm = true; 1284 } 1285 1286 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1287 // declaration of each parameter shall include an identifier. 1288 if (Param->getIdentifier() == 0 && 1289 !Param->isImplicit() && 1290 !getLangOptions().CPlusPlus) 1291 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1292 } 1293 1294 return HasInvalidParm; 1295} 1296 1297/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1298/// no declarator (e.g. "struct foo;") is parsed. 1299Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1300 // FIXME: Error on auto/register at file scope 1301 // FIXME: Error on inline/virtual/explicit 1302 // FIXME: Error on invalid restrict 1303 // FIXME: Warn on useless __thread 1304 // FIXME: Warn on useless const/volatile 1305 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1306 // FIXME: Warn on useless attributes 1307 Decl *TagD = 0; 1308 TagDecl *Tag = 0; 1309 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1310 DS.getTypeSpecType() == DeclSpec::TST_struct || 1311 DS.getTypeSpecType() == DeclSpec::TST_union || 1312 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1313 TagD = static_cast<Decl *>(DS.getTypeRep()); 1314 1315 if (!TagD) // We probably had an error 1316 return DeclPtrTy(); 1317 1318 // Note that the above type specs guarantee that the 1319 // type rep is a Decl, whereas in many of the others 1320 // it's a Type. 1321 Tag = dyn_cast<TagDecl>(TagD); 1322 } 1323 1324 if (DS.isFriendSpecified()) { 1325 // If we're dealing with a class template decl, assume that the 1326 // template routines are handling it. 1327 if (TagD && isa<ClassTemplateDecl>(TagD)) 1328 return DeclPtrTy(); 1329 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1330 } 1331 1332 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1333 if (!Record->getDeclName() && Record->isDefinition() && 1334 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1335 if (getLangOptions().CPlusPlus || 1336 Record->getDeclContext()->isRecord()) 1337 return BuildAnonymousStructOrUnion(S, DS, Record); 1338 1339 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1340 << DS.getSourceRange(); 1341 } 1342 1343 // Microsoft allows unnamed struct/union fields. Don't complain 1344 // about them. 1345 // FIXME: Should we support Microsoft's extensions in this area? 1346 if (Record->getDeclName() && getLangOptions().Microsoft) 1347 return DeclPtrTy::make(Tag); 1348 } 1349 1350 if (!DS.isMissingDeclaratorOk() && 1351 DS.getTypeSpecType() != DeclSpec::TST_error) { 1352 // Warn about typedefs of enums without names, since this is an 1353 // extension in both Microsoft an GNU. 1354 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1355 Tag && isa<EnumDecl>(Tag)) { 1356 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1357 << DS.getSourceRange(); 1358 return DeclPtrTy::make(Tag); 1359 } 1360 1361 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1362 << DS.getSourceRange(); 1363 return DeclPtrTy(); 1364 } 1365 1366 return DeclPtrTy::make(Tag); 1367} 1368 1369/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1370/// anonymous struct or union AnonRecord into the owning context Owner 1371/// and scope S. This routine will be invoked just after we realize 1372/// that an unnamed union or struct is actually an anonymous union or 1373/// struct, e.g., 1374/// 1375/// @code 1376/// union { 1377/// int i; 1378/// float f; 1379/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1380/// // f into the surrounding scope.x 1381/// @endcode 1382/// 1383/// This routine is recursive, injecting the names of nested anonymous 1384/// structs/unions into the owning context and scope as well. 1385bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1386 RecordDecl *AnonRecord) { 1387 bool Invalid = false; 1388 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1389 FEnd = AnonRecord->field_end(); 1390 F != FEnd; ++F) { 1391 if ((*F)->getDeclName()) { 1392 LookupResult R; 1393 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1394 LookupOrdinaryName, true); 1395 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1396 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1397 // C++ [class.union]p2: 1398 // The names of the members of an anonymous union shall be 1399 // distinct from the names of any other entity in the 1400 // scope in which the anonymous union is declared. 1401 unsigned diagKind 1402 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1403 : diag::err_anonymous_struct_member_redecl; 1404 Diag((*F)->getLocation(), diagKind) 1405 << (*F)->getDeclName(); 1406 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1407 Invalid = true; 1408 } else { 1409 // C++ [class.union]p2: 1410 // For the purpose of name lookup, after the anonymous union 1411 // definition, the members of the anonymous union are 1412 // considered to have been defined in the scope in which the 1413 // anonymous union is declared. 1414 Owner->makeDeclVisibleInContext(*F); 1415 S->AddDecl(DeclPtrTy::make(*F)); 1416 IdResolver.AddDecl(*F); 1417 } 1418 } else if (const RecordType *InnerRecordType 1419 = (*F)->getType()->getAs<RecordType>()) { 1420 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1421 if (InnerRecord->isAnonymousStructOrUnion()) 1422 Invalid = Invalid || 1423 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1424 } 1425 } 1426 1427 return Invalid; 1428} 1429 1430/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1431/// anonymous structure or union. Anonymous unions are a C++ feature 1432/// (C++ [class.union]) and a GNU C extension; anonymous structures 1433/// are a GNU C and GNU C++ extension. 1434Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1435 RecordDecl *Record) { 1436 DeclContext *Owner = Record->getDeclContext(); 1437 1438 // Diagnose whether this anonymous struct/union is an extension. 1439 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1440 Diag(Record->getLocation(), diag::ext_anonymous_union); 1441 else if (!Record->isUnion()) 1442 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1443 1444 // C and C++ require different kinds of checks for anonymous 1445 // structs/unions. 1446 bool Invalid = false; 1447 if (getLangOptions().CPlusPlus) { 1448 const char* PrevSpec = 0; 1449 unsigned DiagID; 1450 // C++ [class.union]p3: 1451 // Anonymous unions declared in a named namespace or in the 1452 // global namespace shall be declared static. 1453 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1454 (isa<TranslationUnitDecl>(Owner) || 1455 (isa<NamespaceDecl>(Owner) && 1456 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1457 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1458 Invalid = true; 1459 1460 // Recover by adding 'static'. 1461 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1462 PrevSpec, DiagID); 1463 } 1464 // C++ [class.union]p3: 1465 // A storage class is not allowed in a declaration of an 1466 // anonymous union in a class scope. 1467 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1468 isa<RecordDecl>(Owner)) { 1469 Diag(DS.getStorageClassSpecLoc(), 1470 diag::err_anonymous_union_with_storage_spec); 1471 Invalid = true; 1472 1473 // Recover by removing the storage specifier. 1474 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1475 PrevSpec, DiagID); 1476 } 1477 1478 // C++ [class.union]p2: 1479 // The member-specification of an anonymous union shall only 1480 // define non-static data members. [Note: nested types and 1481 // functions cannot be declared within an anonymous union. ] 1482 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1483 MemEnd = Record->decls_end(); 1484 Mem != MemEnd; ++Mem) { 1485 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1486 // C++ [class.union]p3: 1487 // An anonymous union shall not have private or protected 1488 // members (clause 11). 1489 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1490 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1491 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1492 Invalid = true; 1493 } 1494 } else if ((*Mem)->isImplicit()) { 1495 // Any implicit members are fine. 1496 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1497 // This is a type that showed up in an 1498 // elaborated-type-specifier inside the anonymous struct or 1499 // union, but which actually declares a type outside of the 1500 // anonymous struct or union. It's okay. 1501 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1502 if (!MemRecord->isAnonymousStructOrUnion() && 1503 MemRecord->getDeclName()) { 1504 // This is a nested type declaration. 1505 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1506 << (int)Record->isUnion(); 1507 Invalid = true; 1508 } 1509 } else { 1510 // We have something that isn't a non-static data 1511 // member. Complain about it. 1512 unsigned DK = diag::err_anonymous_record_bad_member; 1513 if (isa<TypeDecl>(*Mem)) 1514 DK = diag::err_anonymous_record_with_type; 1515 else if (isa<FunctionDecl>(*Mem)) 1516 DK = diag::err_anonymous_record_with_function; 1517 else if (isa<VarDecl>(*Mem)) 1518 DK = diag::err_anonymous_record_with_static; 1519 Diag((*Mem)->getLocation(), DK) 1520 << (int)Record->isUnion(); 1521 Invalid = true; 1522 } 1523 } 1524 } 1525 1526 if (!Record->isUnion() && !Owner->isRecord()) { 1527 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1528 << (int)getLangOptions().CPlusPlus; 1529 Invalid = true; 1530 } 1531 1532 // Create a declaration for this anonymous struct/union. 1533 NamedDecl *Anon = 0; 1534 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1535 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1536 /*IdentifierInfo=*/0, 1537 Context.getTypeDeclType(Record), 1538 // FIXME: Type source info. 1539 /*DInfo=*/0, 1540 /*BitWidth=*/0, /*Mutable=*/false); 1541 Anon->setAccess(AS_public); 1542 if (getLangOptions().CPlusPlus) 1543 FieldCollector->Add(cast<FieldDecl>(Anon)); 1544 } else { 1545 VarDecl::StorageClass SC; 1546 switch (DS.getStorageClassSpec()) { 1547 default: assert(0 && "Unknown storage class!"); 1548 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1549 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1550 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1551 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1552 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1553 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1554 case DeclSpec::SCS_mutable: 1555 // mutable can only appear on non-static class members, so it's always 1556 // an error here 1557 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1558 Invalid = true; 1559 SC = VarDecl::None; 1560 break; 1561 } 1562 1563 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1564 /*IdentifierInfo=*/0, 1565 Context.getTypeDeclType(Record), 1566 // FIXME: Type source info. 1567 /*DInfo=*/0, 1568 SC); 1569 } 1570 Anon->setImplicit(); 1571 1572 // Add the anonymous struct/union object to the current 1573 // context. We'll be referencing this object when we refer to one of 1574 // its members. 1575 Owner->addDecl(Anon); 1576 1577 // Inject the members of the anonymous struct/union into the owning 1578 // context and into the identifier resolver chain for name lookup 1579 // purposes. 1580 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1581 Invalid = true; 1582 1583 // Mark this as an anonymous struct/union type. Note that we do not 1584 // do this until after we have already checked and injected the 1585 // members of this anonymous struct/union type, because otherwise 1586 // the members could be injected twice: once by DeclContext when it 1587 // builds its lookup table, and once by 1588 // InjectAnonymousStructOrUnionMembers. 1589 Record->setAnonymousStructOrUnion(true); 1590 1591 if (Invalid) 1592 Anon->setInvalidDecl(); 1593 1594 return DeclPtrTy::make(Anon); 1595} 1596 1597 1598/// GetNameForDeclarator - Determine the full declaration name for the 1599/// given Declarator. 1600DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1601 switch (D.getKind()) { 1602 case Declarator::DK_Abstract: 1603 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1604 return DeclarationName(); 1605 1606 case Declarator::DK_Normal: 1607 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1608 return DeclarationName(D.getIdentifier()); 1609 1610 case Declarator::DK_Constructor: { 1611 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1612 return Context.DeclarationNames.getCXXConstructorName( 1613 Context.getCanonicalType(Ty)); 1614 } 1615 1616 case Declarator::DK_Destructor: { 1617 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1618 return Context.DeclarationNames.getCXXDestructorName( 1619 Context.getCanonicalType(Ty)); 1620 } 1621 1622 case Declarator::DK_Conversion: { 1623 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1624 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1625 return Context.DeclarationNames.getCXXConversionFunctionName( 1626 Context.getCanonicalType(Ty)); 1627 } 1628 1629 case Declarator::DK_Operator: 1630 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1631 return Context.DeclarationNames.getCXXOperatorName( 1632 D.getOverloadedOperator()); 1633 1634 case Declarator::DK_TemplateId: { 1635 TemplateName Name 1636 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1637 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1638 return Template->getDeclName(); 1639 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1640 return Ovl->getDeclName(); 1641 1642 return DeclarationName(); 1643 } 1644 } 1645 1646 assert(false && "Unknown name kind"); 1647 return DeclarationName(); 1648} 1649 1650/// isNearlyMatchingFunction - Determine whether the C++ functions 1651/// Declaration and Definition are "nearly" matching. This heuristic 1652/// is used to improve diagnostics in the case where an out-of-line 1653/// function definition doesn't match any declaration within 1654/// the class or namespace. 1655static bool isNearlyMatchingFunction(ASTContext &Context, 1656 FunctionDecl *Declaration, 1657 FunctionDecl *Definition) { 1658 if (Declaration->param_size() != Definition->param_size()) 1659 return false; 1660 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1661 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1662 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1663 1664 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1665 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1666 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1667 return false; 1668 } 1669 1670 return true; 1671} 1672 1673Sema::DeclPtrTy 1674Sema::HandleDeclarator(Scope *S, Declarator &D, 1675 MultiTemplateParamsArg TemplateParamLists, 1676 bool IsFunctionDefinition) { 1677 DeclarationName Name = GetNameForDeclarator(D); 1678 1679 // All of these full declarators require an identifier. If it doesn't have 1680 // one, the ParsedFreeStandingDeclSpec action should be used. 1681 if (!Name) { 1682 if (!D.isInvalidType()) // Reject this if we think it is valid. 1683 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1684 diag::err_declarator_need_ident) 1685 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1686 return DeclPtrTy(); 1687 } 1688 1689 // The scope passed in may not be a decl scope. Zip up the scope tree until 1690 // we find one that is. 1691 while ((S->getFlags() & Scope::DeclScope) == 0 || 1692 (S->getFlags() & Scope::TemplateParamScope) != 0) 1693 S = S->getParent(); 1694 1695 // If this is an out-of-line definition of a member of a class template 1696 // or class template partial specialization, we may need to rebuild the 1697 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1698 // for more information. 1699 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1700 // handle expressions properly. 1701 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1702 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1703 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1704 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1705 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1706 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1707 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1708 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1709 // FIXME: Preserve type source info. 1710 QualType T = GetTypeFromParser(DS.getTypeRep()); 1711 EnterDeclaratorContext(S, DC); 1712 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1713 ExitDeclaratorContext(S); 1714 if (T.isNull()) 1715 return DeclPtrTy(); 1716 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1717 } 1718 } 1719 1720 DeclContext *DC; 1721 NamedDecl *PrevDecl; 1722 NamedDecl *New; 1723 1724 DeclaratorInfo *DInfo = 0; 1725 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1726 1727 // See if this is a redefinition of a variable in the same scope. 1728 if (D.getCXXScopeSpec().isInvalid()) { 1729 DC = CurContext; 1730 PrevDecl = 0; 1731 D.setInvalidType(); 1732 } else if (!D.getCXXScopeSpec().isSet()) { 1733 LookupNameKind NameKind = LookupOrdinaryName; 1734 1735 // If the declaration we're planning to build will be a function 1736 // or object with linkage, then look for another declaration with 1737 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1738 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1739 /* Do nothing*/; 1740 else if (R->isFunctionType()) { 1741 if (CurContext->isFunctionOrMethod() || 1742 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1743 NameKind = LookupRedeclarationWithLinkage; 1744 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1745 NameKind = LookupRedeclarationWithLinkage; 1746 else if (CurContext->getLookupContext()->isTranslationUnit() && 1747 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1748 NameKind = LookupRedeclarationWithLinkage; 1749 1750 DC = CurContext; 1751 LookupResult R; 1752 LookupName(R, S, Name, NameKind, true, 1753 NameKind == LookupRedeclarationWithLinkage, 1754 D.getIdentifierLoc()); 1755 PrevDecl = R.getAsSingleDecl(Context); 1756 } else { // Something like "int foo::x;" 1757 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1758 1759 if (!DC) { 1760 // If we could not compute the declaration context, it's because the 1761 // declaration context is dependent but does not refer to a class, 1762 // class template, or class template partial specialization. Complain 1763 // and return early, to avoid the coming semantic disaster. 1764 Diag(D.getIdentifierLoc(), 1765 diag::err_template_qualified_declarator_no_match) 1766 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1767 << D.getCXXScopeSpec().getRange(); 1768 return DeclPtrTy(); 1769 } 1770 1771 if (!DC->isDependentContext() && 1772 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1773 return DeclPtrTy(); 1774 1775 LookupResult Res; 1776 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1777 PrevDecl = Res.getAsSingleDecl(Context); 1778 1779 // C++ 7.3.1.2p2: 1780 // Members (including explicit specializations of templates) of a named 1781 // namespace can also be defined outside that namespace by explicit 1782 // qualification of the name being defined, provided that the entity being 1783 // defined was already declared in the namespace and the definition appears 1784 // after the point of declaration in a namespace that encloses the 1785 // declarations namespace. 1786 // 1787 // Note that we only check the context at this point. We don't yet 1788 // have enough information to make sure that PrevDecl is actually 1789 // the declaration we want to match. For example, given: 1790 // 1791 // class X { 1792 // void f(); 1793 // void f(float); 1794 // }; 1795 // 1796 // void X::f(int) { } // ill-formed 1797 // 1798 // In this case, PrevDecl will point to the overload set 1799 // containing the two f's declared in X, but neither of them 1800 // matches. 1801 1802 // First check whether we named the global scope. 1803 if (isa<TranslationUnitDecl>(DC)) { 1804 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1805 << Name << D.getCXXScopeSpec().getRange(); 1806 } else if (!CurContext->Encloses(DC)) { 1807 // The qualifying scope doesn't enclose the original declaration. 1808 // Emit diagnostic based on current scope. 1809 SourceLocation L = D.getIdentifierLoc(); 1810 SourceRange R = D.getCXXScopeSpec().getRange(); 1811 if (isa<FunctionDecl>(CurContext)) 1812 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1813 else 1814 Diag(L, diag::err_invalid_declarator_scope) 1815 << Name << cast<NamedDecl>(DC) << R; 1816 D.setInvalidType(); 1817 } 1818 } 1819 1820 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1821 // Maybe we will complain about the shadowed template parameter. 1822 if (!D.isInvalidType()) 1823 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1824 D.setInvalidType(); 1825 1826 // Just pretend that we didn't see the previous declaration. 1827 PrevDecl = 0; 1828 } 1829 1830 // In C++, the previous declaration we find might be a tag type 1831 // (class or enum). In this case, the new declaration will hide the 1832 // tag type. Note that this does does not apply if we're declaring a 1833 // typedef (C++ [dcl.typedef]p4). 1834 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1835 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1836 PrevDecl = 0; 1837 1838 bool Redeclaration = false; 1839 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1840 if (TemplateParamLists.size()) { 1841 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1842 return DeclPtrTy(); 1843 } 1844 1845 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1846 } else if (R->isFunctionType()) { 1847 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1848 move(TemplateParamLists), 1849 IsFunctionDefinition, Redeclaration); 1850 } else { 1851 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1852 move(TemplateParamLists), 1853 Redeclaration); 1854 } 1855 1856 if (New == 0) 1857 return DeclPtrTy(); 1858 1859 // If this has an identifier and is not an invalid redeclaration or 1860 // function template specialization, add it to the scope stack. 1861 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1862 !(isa<FunctionDecl>(New) && 1863 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1864 PushOnScopeChains(New, S); 1865 1866 return DeclPtrTy::make(New); 1867} 1868 1869/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1870/// types into constant array types in certain situations which would otherwise 1871/// be errors (for GCC compatibility). 1872static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1873 ASTContext &Context, 1874 bool &SizeIsNegative) { 1875 // This method tries to turn a variable array into a constant 1876 // array even when the size isn't an ICE. This is necessary 1877 // for compatibility with code that depends on gcc's buggy 1878 // constant expression folding, like struct {char x[(int)(char*)2];} 1879 SizeIsNegative = false; 1880 1881 QualifierCollector Qs; 1882 const Type *Ty = Qs.strip(T); 1883 1884 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1885 QualType Pointee = PTy->getPointeeType(); 1886 QualType FixedType = 1887 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1888 if (FixedType.isNull()) return FixedType; 1889 FixedType = Context.getPointerType(FixedType); 1890 return Qs.apply(FixedType); 1891 } 1892 1893 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1894 if (!VLATy) 1895 return QualType(); 1896 // FIXME: We should probably handle this case 1897 if (VLATy->getElementType()->isVariablyModifiedType()) 1898 return QualType(); 1899 1900 Expr::EvalResult EvalResult; 1901 if (!VLATy->getSizeExpr() || 1902 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1903 !EvalResult.Val.isInt()) 1904 return QualType(); 1905 1906 llvm::APSInt &Res = EvalResult.Val.getInt(); 1907 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1908 // TODO: preserve the size expression in declarator info 1909 return Context.getConstantArrayType(VLATy->getElementType(), 1910 Res, ArrayType::Normal, 0); 1911 } 1912 1913 SizeIsNegative = true; 1914 return QualType(); 1915} 1916 1917/// \brief Register the given locally-scoped external C declaration so 1918/// that it can be found later for redeclarations 1919void 1920Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1921 Scope *S) { 1922 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1923 "Decl is not a locally-scoped decl!"); 1924 // Note that we have a locally-scoped external with this name. 1925 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1926 1927 if (!PrevDecl) 1928 return; 1929 1930 // If there was a previous declaration of this variable, it may be 1931 // in our identifier chain. Update the identifier chain with the new 1932 // declaration. 1933 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1934 // The previous declaration was found on the identifer resolver 1935 // chain, so remove it from its scope. 1936 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1937 S = S->getParent(); 1938 1939 if (S) 1940 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1941 } 1942} 1943 1944/// \brief Diagnose function specifiers on a declaration of an identifier that 1945/// does not identify a function. 1946void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1947 // FIXME: We should probably indicate the identifier in question to avoid 1948 // confusion for constructs like "inline int a(), b;" 1949 if (D.getDeclSpec().isInlineSpecified()) 1950 Diag(D.getDeclSpec().getInlineSpecLoc(), 1951 diag::err_inline_non_function); 1952 1953 if (D.getDeclSpec().isVirtualSpecified()) 1954 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1955 diag::err_virtual_non_function); 1956 1957 if (D.getDeclSpec().isExplicitSpecified()) 1958 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1959 diag::err_explicit_non_function); 1960} 1961 1962NamedDecl* 1963Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1964 QualType R, DeclaratorInfo *DInfo, 1965 NamedDecl* PrevDecl, bool &Redeclaration) { 1966 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1967 if (D.getCXXScopeSpec().isSet()) { 1968 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1969 << D.getCXXScopeSpec().getRange(); 1970 D.setInvalidType(); 1971 // Pretend we didn't see the scope specifier. 1972 DC = 0; 1973 } 1974 1975 if (getLangOptions().CPlusPlus) { 1976 // Check that there are no default arguments (C++ only). 1977 CheckExtraCXXDefaultArguments(D); 1978 } 1979 1980 DiagnoseFunctionSpecifiers(D); 1981 1982 if (D.getDeclSpec().isThreadSpecified()) 1983 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1984 1985 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1986 if (!NewTD) return 0; 1987 1988 if (D.isInvalidType()) 1989 NewTD->setInvalidDecl(); 1990 1991 // Handle attributes prior to checking for duplicates in MergeVarDecl 1992 ProcessDeclAttributes(S, NewTD, D); 1993 // Merge the decl with the existing one if appropriate. If the decl is 1994 // in an outer scope, it isn't the same thing. 1995 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1996 Redeclaration = true; 1997 MergeTypeDefDecl(NewTD, PrevDecl); 1998 } 1999 2000 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2001 // then it shall have block scope. 2002 QualType T = NewTD->getUnderlyingType(); 2003 if (T->isVariablyModifiedType()) { 2004 CurFunctionNeedsScopeChecking = true; 2005 2006 if (S->getFnParent() == 0) { 2007 bool SizeIsNegative; 2008 QualType FixedTy = 2009 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2010 if (!FixedTy.isNull()) { 2011 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2012 NewTD->setUnderlyingType(FixedTy); 2013 } else { 2014 if (SizeIsNegative) 2015 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2016 else if (T->isVariableArrayType()) 2017 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2018 else 2019 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2020 NewTD->setInvalidDecl(); 2021 } 2022 } 2023 } 2024 2025 // If this is the C FILE type, notify the AST context. 2026 if (IdentifierInfo *II = NewTD->getIdentifier()) 2027 if (!NewTD->isInvalidDecl() && 2028 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2029 if (II->isStr("FILE")) 2030 Context.setFILEDecl(NewTD); 2031 else if (II->isStr("jmp_buf")) 2032 Context.setjmp_bufDecl(NewTD); 2033 else if (II->isStr("sigjmp_buf")) 2034 Context.setsigjmp_bufDecl(NewTD); 2035 } 2036 2037 return NewTD; 2038} 2039 2040/// \brief Determines whether the given declaration is an out-of-scope 2041/// previous declaration. 2042/// 2043/// This routine should be invoked when name lookup has found a 2044/// previous declaration (PrevDecl) that is not in the scope where a 2045/// new declaration by the same name is being introduced. If the new 2046/// declaration occurs in a local scope, previous declarations with 2047/// linkage may still be considered previous declarations (C99 2048/// 6.2.2p4-5, C++ [basic.link]p6). 2049/// 2050/// \param PrevDecl the previous declaration found by name 2051/// lookup 2052/// 2053/// \param DC the context in which the new declaration is being 2054/// declared. 2055/// 2056/// \returns true if PrevDecl is an out-of-scope previous declaration 2057/// for a new delcaration with the same name. 2058static bool 2059isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2060 ASTContext &Context) { 2061 if (!PrevDecl) 2062 return 0; 2063 2064 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2065 // case we need to check each of the overloaded functions. 2066 if (!PrevDecl->hasLinkage()) 2067 return false; 2068 2069 if (Context.getLangOptions().CPlusPlus) { 2070 // C++ [basic.link]p6: 2071 // If there is a visible declaration of an entity with linkage 2072 // having the same name and type, ignoring entities declared 2073 // outside the innermost enclosing namespace scope, the block 2074 // scope declaration declares that same entity and receives the 2075 // linkage of the previous declaration. 2076 DeclContext *OuterContext = DC->getLookupContext(); 2077 if (!OuterContext->isFunctionOrMethod()) 2078 // This rule only applies to block-scope declarations. 2079 return false; 2080 else { 2081 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2082 if (PrevOuterContext->isRecord()) 2083 // We found a member function: ignore it. 2084 return false; 2085 else { 2086 // Find the innermost enclosing namespace for the new and 2087 // previous declarations. 2088 while (!OuterContext->isFileContext()) 2089 OuterContext = OuterContext->getParent(); 2090 while (!PrevOuterContext->isFileContext()) 2091 PrevOuterContext = PrevOuterContext->getParent(); 2092 2093 // The previous declaration is in a different namespace, so it 2094 // isn't the same function. 2095 if (OuterContext->getPrimaryContext() != 2096 PrevOuterContext->getPrimaryContext()) 2097 return false; 2098 } 2099 } 2100 } 2101 2102 return true; 2103} 2104 2105NamedDecl* 2106Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2107 QualType R, DeclaratorInfo *DInfo, 2108 NamedDecl* PrevDecl, 2109 MultiTemplateParamsArg TemplateParamLists, 2110 bool &Redeclaration) { 2111 DeclarationName Name = GetNameForDeclarator(D); 2112 2113 // Check that there are no default arguments (C++ only). 2114 if (getLangOptions().CPlusPlus) 2115 CheckExtraCXXDefaultArguments(D); 2116 2117 VarDecl *NewVD; 2118 VarDecl::StorageClass SC; 2119 switch (D.getDeclSpec().getStorageClassSpec()) { 2120 default: assert(0 && "Unknown storage class!"); 2121 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2122 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2123 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2124 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2125 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2126 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2127 case DeclSpec::SCS_mutable: 2128 // mutable can only appear on non-static class members, so it's always 2129 // an error here 2130 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2131 D.setInvalidType(); 2132 SC = VarDecl::None; 2133 break; 2134 } 2135 2136 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2137 if (!II) { 2138 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2139 << Name.getAsString(); 2140 return 0; 2141 } 2142 2143 DiagnoseFunctionSpecifiers(D); 2144 2145 if (!DC->isRecord() && S->getFnParent() == 0) { 2146 // C99 6.9p2: The storage-class specifiers auto and register shall not 2147 // appear in the declaration specifiers in an external declaration. 2148 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2149 2150 // If this is a register variable with an asm label specified, then this 2151 // is a GNU extension. 2152 if (SC == VarDecl::Register && D.getAsmLabel()) 2153 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2154 else 2155 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2156 D.setInvalidType(); 2157 } 2158 } 2159 if (DC->isRecord() && !CurContext->isRecord()) { 2160 // This is an out-of-line definition of a static data member. 2161 if (SC == VarDecl::Static) { 2162 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2163 diag::err_static_out_of_line) 2164 << CodeModificationHint::CreateRemoval( 2165 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2166 } else if (SC == VarDecl::None) 2167 SC = VarDecl::Static; 2168 } 2169 if (SC == VarDecl::Static) { 2170 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2171 if (RD->isLocalClass()) 2172 Diag(D.getIdentifierLoc(), 2173 diag::err_static_data_member_not_allowed_in_local_class) 2174 << Name << RD->getDeclName(); 2175 } 2176 } 2177 2178 // Match up the template parameter lists with the scope specifier, then 2179 // determine whether we have a template or a template specialization. 2180 bool isExplicitSpecialization = false; 2181 if (TemplateParameterList *TemplateParams 2182 = MatchTemplateParametersToScopeSpecifier( 2183 D.getDeclSpec().getSourceRange().getBegin(), 2184 D.getCXXScopeSpec(), 2185 (TemplateParameterList**)TemplateParamLists.get(), 2186 TemplateParamLists.size(), 2187 isExplicitSpecialization)) { 2188 if (TemplateParams->size() > 0) { 2189 // There is no such thing as a variable template. 2190 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2191 << II 2192 << SourceRange(TemplateParams->getTemplateLoc(), 2193 TemplateParams->getRAngleLoc()); 2194 return 0; 2195 } else { 2196 // There is an extraneous 'template<>' for this variable. Complain 2197 // about it, but allow the declaration of the variable. 2198 Diag(TemplateParams->getTemplateLoc(), 2199 diag::err_template_variable_noparams) 2200 << II 2201 << SourceRange(TemplateParams->getTemplateLoc(), 2202 TemplateParams->getRAngleLoc()); 2203 2204 isExplicitSpecialization = true; 2205 } 2206 } 2207 2208 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2209 II, R, DInfo, SC); 2210 2211 if (D.isInvalidType()) 2212 NewVD->setInvalidDecl(); 2213 2214 if (D.getDeclSpec().isThreadSpecified()) { 2215 if (NewVD->hasLocalStorage()) 2216 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2217 else if (!Context.Target.isTLSSupported()) 2218 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2219 else 2220 NewVD->setThreadSpecified(true); 2221 } 2222 2223 // Set the lexical context. If the declarator has a C++ scope specifier, the 2224 // lexical context will be different from the semantic context. 2225 NewVD->setLexicalDeclContext(CurContext); 2226 2227 // Handle attributes prior to checking for duplicates in MergeVarDecl 2228 ProcessDeclAttributes(S, NewVD, D); 2229 2230 // Handle GNU asm-label extension (encoded as an attribute). 2231 if (Expr *E = (Expr*) D.getAsmLabel()) { 2232 // The parser guarantees this is a string. 2233 StringLiteral *SE = cast<StringLiteral>(E); 2234 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2235 SE->getByteLength()))); 2236 } 2237 2238 // If name lookup finds a previous declaration that is not in the 2239 // same scope as the new declaration, this may still be an 2240 // acceptable redeclaration. 2241 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2242 !(NewVD->hasLinkage() && 2243 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2244 PrevDecl = 0; 2245 2246 // Merge the decl with the existing one if appropriate. 2247 if (PrevDecl) { 2248 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2249 // The user tried to define a non-static data member 2250 // out-of-line (C++ [dcl.meaning]p1). 2251 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2252 << D.getCXXScopeSpec().getRange(); 2253 PrevDecl = 0; 2254 NewVD->setInvalidDecl(); 2255 } 2256 } else if (D.getCXXScopeSpec().isSet()) { 2257 // No previous declaration in the qualifying scope. 2258 Diag(D.getIdentifierLoc(), diag::err_no_member) 2259 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2260 << D.getCXXScopeSpec().getRange(); 2261 NewVD->setInvalidDecl(); 2262 } 2263 2264 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2265 2266 // This is an explicit specialization of a static data member. Check it. 2267 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2268 CheckMemberSpecialization(NewVD, PrevDecl)) 2269 NewVD->setInvalidDecl(); 2270 2271 // attributes declared post-definition are currently ignored 2272 if (PrevDecl) { 2273 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2274 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2275 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2276 Diag(Def->getLocation(), diag::note_previous_definition); 2277 } 2278 } 2279 2280 // If this is a locally-scoped extern C variable, update the map of 2281 // such variables. 2282 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2283 !NewVD->isInvalidDecl()) 2284 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2285 2286 return NewVD; 2287} 2288 2289/// \brief Perform semantic checking on a newly-created variable 2290/// declaration. 2291/// 2292/// This routine performs all of the type-checking required for a 2293/// variable declaration once it has been built. It is used both to 2294/// check variables after they have been parsed and their declarators 2295/// have been translated into a declaration, and to check variables 2296/// that have been instantiated from a template. 2297/// 2298/// Sets NewVD->isInvalidDecl() if an error was encountered. 2299void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2300 bool &Redeclaration) { 2301 // If the decl is already known invalid, don't check it. 2302 if (NewVD->isInvalidDecl()) 2303 return; 2304 2305 QualType T = NewVD->getType(); 2306 2307 if (T->isObjCInterfaceType()) { 2308 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2309 return NewVD->setInvalidDecl(); 2310 } 2311 2312 // The variable can not have an abstract class type. 2313 if (RequireNonAbstractType(NewVD->getLocation(), T, 2314 diag::err_abstract_type_in_decl, 2315 AbstractVariableType)) 2316 return NewVD->setInvalidDecl(); 2317 2318 // Emit an error if an address space was applied to decl with local storage. 2319 // This includes arrays of objects with address space qualifiers, but not 2320 // automatic variables that point to other address spaces. 2321 // ISO/IEC TR 18037 S5.1.2 2322 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2323 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2324 return NewVD->setInvalidDecl(); 2325 } 2326 2327 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2328 && !NewVD->hasAttr<BlocksAttr>()) 2329 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2330 2331 bool isVM = T->isVariablyModifiedType(); 2332 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2333 NewVD->hasAttr<BlocksAttr>()) 2334 CurFunctionNeedsScopeChecking = true; 2335 2336 if ((isVM && NewVD->hasLinkage()) || 2337 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2338 bool SizeIsNegative; 2339 QualType FixedTy = 2340 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2341 2342 if (FixedTy.isNull() && T->isVariableArrayType()) { 2343 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2344 // FIXME: This won't give the correct result for 2345 // int a[10][n]; 2346 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2347 2348 if (NewVD->isFileVarDecl()) 2349 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2350 << SizeRange; 2351 else if (NewVD->getStorageClass() == VarDecl::Static) 2352 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2353 << SizeRange; 2354 else 2355 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2356 << SizeRange; 2357 return NewVD->setInvalidDecl(); 2358 } 2359 2360 if (FixedTy.isNull()) { 2361 if (NewVD->isFileVarDecl()) 2362 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2363 else 2364 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2365 return NewVD->setInvalidDecl(); 2366 } 2367 2368 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2369 NewVD->setType(FixedTy); 2370 } 2371 2372 if (!PrevDecl && NewVD->isExternC()) { 2373 // Since we did not find anything by this name and we're declaring 2374 // an extern "C" variable, look for a non-visible extern "C" 2375 // declaration with the same name. 2376 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2377 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2378 if (Pos != LocallyScopedExternalDecls.end()) 2379 PrevDecl = Pos->second; 2380 } 2381 2382 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2383 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2384 << T; 2385 return NewVD->setInvalidDecl(); 2386 } 2387 2388 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2389 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2390 return NewVD->setInvalidDecl(); 2391 } 2392 2393 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2394 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2395 return NewVD->setInvalidDecl(); 2396 } 2397 2398 if (PrevDecl) { 2399 Redeclaration = true; 2400 MergeVarDecl(NewVD, PrevDecl); 2401 } 2402} 2403 2404static bool isUsingDecl(Decl *D) { 2405 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2406} 2407 2408/// \brief Data used with FindOverriddenMethod 2409struct FindOverriddenMethodData { 2410 Sema *S; 2411 CXXMethodDecl *Method; 2412}; 2413 2414/// \brief Member lookup function that determines whether a given C++ 2415/// method overrides a method in a base class, to be used with 2416/// CXXRecordDecl::lookupInBases(). 2417static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2418 CXXBasePath &Path, 2419 void *UserData) { 2420 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2421 2422 FindOverriddenMethodData *Data 2423 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2424 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2425 Path.Decls.first != Path.Decls.second; 2426 ++Path.Decls.first) { 2427 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2428 OverloadedFunctionDecl::function_iterator MatchedDecl; 2429 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2430 return true; 2431 } 2432 } 2433 2434 return false; 2435} 2436 2437NamedDecl* 2438Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2439 QualType R, DeclaratorInfo *DInfo, 2440 NamedDecl* PrevDecl, 2441 MultiTemplateParamsArg TemplateParamLists, 2442 bool IsFunctionDefinition, bool &Redeclaration) { 2443 assert(R.getTypePtr()->isFunctionType()); 2444 2445 DeclarationName Name = GetNameForDeclarator(D); 2446 FunctionDecl::StorageClass SC = FunctionDecl::None; 2447 switch (D.getDeclSpec().getStorageClassSpec()) { 2448 default: assert(0 && "Unknown storage class!"); 2449 case DeclSpec::SCS_auto: 2450 case DeclSpec::SCS_register: 2451 case DeclSpec::SCS_mutable: 2452 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2453 diag::err_typecheck_sclass_func); 2454 D.setInvalidType(); 2455 break; 2456 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2457 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2458 case DeclSpec::SCS_static: { 2459 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2460 // C99 6.7.1p5: 2461 // The declaration of an identifier for a function that has 2462 // block scope shall have no explicit storage-class specifier 2463 // other than extern 2464 // See also (C++ [dcl.stc]p4). 2465 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2466 diag::err_static_block_func); 2467 SC = FunctionDecl::None; 2468 } else 2469 SC = FunctionDecl::Static; 2470 break; 2471 } 2472 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2473 } 2474 2475 if (D.getDeclSpec().isThreadSpecified()) 2476 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2477 2478 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2479 bool isInline = D.getDeclSpec().isInlineSpecified(); 2480 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2481 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2482 2483 // Check that the return type is not an abstract class type. 2484 // For record types, this is done by the AbstractClassUsageDiagnoser once 2485 // the class has been completely parsed. 2486 if (!DC->isRecord() && 2487 RequireNonAbstractType(D.getIdentifierLoc(), 2488 R->getAs<FunctionType>()->getResultType(), 2489 diag::err_abstract_type_in_decl, 2490 AbstractReturnType)) 2491 D.setInvalidType(); 2492 2493 // Do not allow returning a objc interface by-value. 2494 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2495 Diag(D.getIdentifierLoc(), 2496 diag::err_object_cannot_be_passed_returned_by_value) << 0 2497 << R->getAs<FunctionType>()->getResultType(); 2498 D.setInvalidType(); 2499 } 2500 2501 bool isVirtualOkay = false; 2502 FunctionDecl *NewFD; 2503 2504 if (isFriend) { 2505 // DC is the namespace in which the function is being declared. 2506 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2507 "friend function being created in a non-namespace context"); 2508 2509 // C++ [class.friend]p5 2510 // A function can be defined in a friend declaration of a 2511 // class . . . . Such a function is implicitly inline. 2512 isInline |= IsFunctionDefinition; 2513 } 2514 2515 if (D.getKind() == Declarator::DK_Constructor) { 2516 // This is a C++ constructor declaration. 2517 assert(DC->isRecord() && 2518 "Constructors can only be declared in a member context"); 2519 2520 R = CheckConstructorDeclarator(D, R, SC); 2521 2522 // Create the new declaration 2523 NewFD = CXXConstructorDecl::Create(Context, 2524 cast<CXXRecordDecl>(DC), 2525 D.getIdentifierLoc(), Name, R, DInfo, 2526 isExplicit, isInline, 2527 /*isImplicitlyDeclared=*/false); 2528 } else if (D.getKind() == Declarator::DK_Destructor) { 2529 // This is a C++ destructor declaration. 2530 if (DC->isRecord()) { 2531 R = CheckDestructorDeclarator(D, SC); 2532 2533 NewFD = CXXDestructorDecl::Create(Context, 2534 cast<CXXRecordDecl>(DC), 2535 D.getIdentifierLoc(), Name, R, 2536 isInline, 2537 /*isImplicitlyDeclared=*/false); 2538 2539 isVirtualOkay = true; 2540 } else { 2541 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2542 2543 // Create a FunctionDecl to satisfy the function definition parsing 2544 // code path. 2545 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2546 Name, R, DInfo, SC, isInline, 2547 /*hasPrototype=*/true); 2548 D.setInvalidType(); 2549 } 2550 } else if (D.getKind() == Declarator::DK_Conversion) { 2551 if (!DC->isRecord()) { 2552 Diag(D.getIdentifierLoc(), 2553 diag::err_conv_function_not_member); 2554 return 0; 2555 } 2556 2557 CheckConversionDeclarator(D, R, SC); 2558 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2559 D.getIdentifierLoc(), Name, R, DInfo, 2560 isInline, isExplicit); 2561 2562 isVirtualOkay = true; 2563 } else if (DC->isRecord()) { 2564 // If the of the function is the same as the name of the record, then this 2565 // must be an invalid constructor that has a return type. 2566 // (The parser checks for a return type and makes the declarator a 2567 // constructor if it has no return type). 2568 // must have an invalid constructor that has a return type 2569 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2570 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2571 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2572 << SourceRange(D.getIdentifierLoc()); 2573 return 0; 2574 } 2575 2576 // This is a C++ method declaration. 2577 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2578 D.getIdentifierLoc(), Name, R, DInfo, 2579 (SC == FunctionDecl::Static), isInline); 2580 2581 isVirtualOkay = (SC != FunctionDecl::Static); 2582 } else { 2583 // Determine whether the function was written with a 2584 // prototype. This true when: 2585 // - we're in C++ (where every function has a prototype), 2586 // - there is a prototype in the declarator, or 2587 // - the type R of the function is some kind of typedef or other reference 2588 // to a type name (which eventually refers to a function type). 2589 bool HasPrototype = 2590 getLangOptions().CPlusPlus || 2591 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2592 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2593 2594 NewFD = FunctionDecl::Create(Context, DC, 2595 D.getIdentifierLoc(), 2596 Name, R, DInfo, SC, isInline, HasPrototype); 2597 } 2598 2599 if (D.isInvalidType()) 2600 NewFD->setInvalidDecl(); 2601 2602 // Set the lexical context. If the declarator has a C++ 2603 // scope specifier, or is the object of a friend declaration, the 2604 // lexical context will be different from the semantic context. 2605 NewFD->setLexicalDeclContext(CurContext); 2606 2607 // Match up the template parameter lists with the scope specifier, then 2608 // determine whether we have a template or a template specialization. 2609 FunctionTemplateDecl *FunctionTemplate = 0; 2610 bool isExplicitSpecialization = false; 2611 bool isFunctionTemplateSpecialization = false; 2612 if (TemplateParameterList *TemplateParams 2613 = MatchTemplateParametersToScopeSpecifier( 2614 D.getDeclSpec().getSourceRange().getBegin(), 2615 D.getCXXScopeSpec(), 2616 (TemplateParameterList**)TemplateParamLists.get(), 2617 TemplateParamLists.size(), 2618 isExplicitSpecialization)) { 2619 if (TemplateParams->size() > 0) { 2620 // This is a function template 2621 2622 // Check that we can declare a template here. 2623 if (CheckTemplateDeclScope(S, TemplateParams)) 2624 return 0; 2625 2626 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2627 NewFD->getLocation(), 2628 Name, TemplateParams, 2629 NewFD); 2630 FunctionTemplate->setLexicalDeclContext(CurContext); 2631 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2632 } else { 2633 // This is a function template specialization. 2634 isFunctionTemplateSpecialization = true; 2635 } 2636 2637 // FIXME: Free this memory properly. 2638 TemplateParamLists.release(); 2639 } 2640 2641 // C++ [dcl.fct.spec]p5: 2642 // The virtual specifier shall only be used in declarations of 2643 // nonstatic class member functions that appear within a 2644 // member-specification of a class declaration; see 10.3. 2645 // 2646 if (isVirtual && !NewFD->isInvalidDecl()) { 2647 if (!isVirtualOkay) { 2648 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2649 diag::err_virtual_non_function); 2650 } else if (!CurContext->isRecord()) { 2651 // 'virtual' was specified outside of the class. 2652 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2653 << CodeModificationHint::CreateRemoval( 2654 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2655 } else { 2656 // Okay: Add virtual to the method. 2657 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2658 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2659 CurClass->setAggregate(false); 2660 CurClass->setPOD(false); 2661 CurClass->setEmpty(false); 2662 CurClass->setPolymorphic(true); 2663 CurClass->setHasTrivialConstructor(false); 2664 CurClass->setHasTrivialCopyConstructor(false); 2665 CurClass->setHasTrivialCopyAssignment(false); 2666 } 2667 } 2668 2669 if (isFriend) { 2670 if (FunctionTemplate) { 2671 FunctionTemplate->setObjectOfFriendDecl( 2672 /* PreviouslyDeclared= */ PrevDecl != NULL); 2673 FunctionTemplate->setAccess(AS_public); 2674 } 2675 else 2676 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2677 2678 NewFD->setAccess(AS_public); 2679 } 2680 2681 2682 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2683 // Look for virtual methods in base classes that this method might override. 2684 CXXBasePaths Paths; 2685 FindOverriddenMethodData Data; 2686 Data.Method = NewMD; 2687 Data.S = this; 2688 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2689 Paths)) { 2690 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2691 E = Paths.found_decls_end(); I != E; ++I) { 2692 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2693 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2694 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2695 NewMD->addOverriddenMethod(OldMD); 2696 } 2697 } 2698 } 2699 } 2700 2701 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2702 !CurContext->isRecord()) { 2703 // C++ [class.static]p1: 2704 // A data or function member of a class may be declared static 2705 // in a class definition, in which case it is a static member of 2706 // the class. 2707 2708 // Complain about the 'static' specifier if it's on an out-of-line 2709 // member function definition. 2710 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2711 diag::err_static_out_of_line) 2712 << CodeModificationHint::CreateRemoval( 2713 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2714 } 2715 2716 // Handle GNU asm-label extension (encoded as an attribute). 2717 if (Expr *E = (Expr*) D.getAsmLabel()) { 2718 // The parser guarantees this is a string. 2719 StringLiteral *SE = cast<StringLiteral>(E); 2720 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2721 SE->getByteLength()))); 2722 } 2723 2724 // Copy the parameter declarations from the declarator D to the function 2725 // declaration NewFD, if they are available. First scavenge them into Params. 2726 llvm::SmallVector<ParmVarDecl*, 16> Params; 2727 if (D.getNumTypeObjects() > 0) { 2728 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2729 2730 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2731 // function that takes no arguments, not a function that takes a 2732 // single void argument. 2733 // We let through "const void" here because Sema::GetTypeForDeclarator 2734 // already checks for that case. 2735 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2736 FTI.ArgInfo[0].Param && 2737 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2738 // Empty arg list, don't push any params. 2739 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2740 2741 // In C++, the empty parameter-type-list must be spelled "void"; a 2742 // typedef of void is not permitted. 2743 if (getLangOptions().CPlusPlus && 2744 Param->getType().getUnqualifiedType() != Context.VoidTy) 2745 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2746 // FIXME: Leaks decl? 2747 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2748 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2749 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2750 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2751 Param->setDeclContext(NewFD); 2752 Params.push_back(Param); 2753 } 2754 } 2755 2756 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2757 // When we're declaring a function with a typedef, typeof, etc as in the 2758 // following example, we'll need to synthesize (unnamed) 2759 // parameters for use in the declaration. 2760 // 2761 // @code 2762 // typedef void fn(int); 2763 // fn f; 2764 // @endcode 2765 2766 // Synthesize a parameter for each argument type. 2767 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2768 AE = FT->arg_type_end(); AI != AE; ++AI) { 2769 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2770 SourceLocation(), 0, 2771 *AI, /*DInfo=*/0, 2772 VarDecl::None, 0); 2773 Param->setImplicit(); 2774 Params.push_back(Param); 2775 } 2776 } else { 2777 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2778 "Should not need args for typedef of non-prototype fn"); 2779 } 2780 // Finally, we know we have the right number of parameters, install them. 2781 NewFD->setParams(Context, Params.data(), Params.size()); 2782 2783 // If name lookup finds a previous declaration that is not in the 2784 // same scope as the new declaration, this may still be an 2785 // acceptable redeclaration. 2786 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2787 !(NewFD->hasLinkage() && 2788 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2789 PrevDecl = 0; 2790 2791 // If the declarator is a template-id, translate the parser's template 2792 // argument list into our AST format. 2793 bool HasExplicitTemplateArgs = false; 2794 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2795 SourceLocation LAngleLoc, RAngleLoc; 2796 if (D.getKind() == Declarator::DK_TemplateId) { 2797 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2798 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2799 TemplateId->getTemplateArgs(), 2800 TemplateId->getTemplateArgIsType(), 2801 TemplateId->NumArgs); 2802 translateTemplateArguments(TemplateArgsPtr, 2803 TemplateId->getTemplateArgLocations(), 2804 TemplateArgs); 2805 TemplateArgsPtr.release(); 2806 2807 HasExplicitTemplateArgs = true; 2808 LAngleLoc = TemplateId->LAngleLoc; 2809 RAngleLoc = TemplateId->RAngleLoc; 2810 2811 if (FunctionTemplate) { 2812 // FIXME: Diagnose function template with explicit template 2813 // arguments. 2814 HasExplicitTemplateArgs = false; 2815 } else if (!isFunctionTemplateSpecialization && 2816 !D.getDeclSpec().isFriendSpecified()) { 2817 // We have encountered something that the user meant to be a 2818 // specialization (because it has explicitly-specified template 2819 // arguments) but that was not introduced with a "template<>" (or had 2820 // too few of them). 2821 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2822 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2823 << CodeModificationHint::CreateInsertion( 2824 D.getDeclSpec().getSourceRange().getBegin(), 2825 "template<> "); 2826 isFunctionTemplateSpecialization = true; 2827 } 2828 } 2829 2830 if (isFunctionTemplateSpecialization) { 2831 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2832 LAngleLoc, TemplateArgs.data(), 2833 TemplateArgs.size(), RAngleLoc, 2834 PrevDecl)) 2835 NewFD->setInvalidDecl(); 2836 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2837 CheckMemberSpecialization(NewFD, PrevDecl)) 2838 NewFD->setInvalidDecl(); 2839 2840 // Perform semantic checking on the function declaration. 2841 bool OverloadableAttrRequired = false; // FIXME: HACK! 2842 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2843 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2844 2845 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2846 // An out-of-line member function declaration must also be a 2847 // definition (C++ [dcl.meaning]p1). 2848 // Note that this is not the case for explicit specializations of 2849 // function templates or member functions of class templates, per 2850 // C++ [temp.expl.spec]p2. 2851 if (!IsFunctionDefinition && !isFriend && 2852 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2853 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2854 << D.getCXXScopeSpec().getRange(); 2855 NewFD->setInvalidDecl(); 2856 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2857 // The user tried to provide an out-of-line definition for a 2858 // function that is a member of a class or namespace, but there 2859 // was no such member function declared (C++ [class.mfct]p2, 2860 // C++ [namespace.memdef]p2). For example: 2861 // 2862 // class X { 2863 // void f() const; 2864 // }; 2865 // 2866 // void X::f() { } // ill-formed 2867 // 2868 // Complain about this problem, and attempt to suggest close 2869 // matches (e.g., those that differ only in cv-qualifiers and 2870 // whether the parameter types are references). 2871 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2872 << Name << DC << D.getCXXScopeSpec().getRange(); 2873 NewFD->setInvalidDecl(); 2874 2875 LookupResult Prev; 2876 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2877 assert(!Prev.isAmbiguous() && 2878 "Cannot have an ambiguity in previous-declaration lookup"); 2879 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2880 Func != FuncEnd; ++Func) { 2881 if (isa<FunctionDecl>(*Func) && 2882 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2883 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2884 } 2885 2886 PrevDecl = 0; 2887 } 2888 } 2889 2890 // Handle attributes. We need to have merged decls when handling attributes 2891 // (for example to check for conflicts, etc). 2892 // FIXME: This needs to happen before we merge declarations. Then, 2893 // let attribute merging cope with attribute conflicts. 2894 ProcessDeclAttributes(S, NewFD, D); 2895 2896 // attributes declared post-definition are currently ignored 2897 if (Redeclaration && PrevDecl) { 2898 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2899 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2900 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2901 Diag(Def->getLocation(), diag::note_previous_definition); 2902 } 2903 } 2904 2905 AddKnownFunctionAttributes(NewFD); 2906 2907 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2908 // If a function name is overloadable in C, then every function 2909 // with that name must be marked "overloadable". 2910 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2911 << Redeclaration << NewFD; 2912 if (PrevDecl) 2913 Diag(PrevDecl->getLocation(), 2914 diag::note_attribute_overloadable_prev_overload); 2915 NewFD->addAttr(::new (Context) OverloadableAttr()); 2916 } 2917 2918 // If this is a locally-scoped extern C function, update the 2919 // map of such names. 2920 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2921 && !NewFD->isInvalidDecl()) 2922 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2923 2924 // Set this FunctionDecl's range up to the right paren. 2925 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2926 2927 if (FunctionTemplate && NewFD->isInvalidDecl()) 2928 FunctionTemplate->setInvalidDecl(); 2929 2930 if (FunctionTemplate) 2931 return FunctionTemplate; 2932 2933 return NewFD; 2934} 2935 2936/// \brief Perform semantic checking of a new function declaration. 2937/// 2938/// Performs semantic analysis of the new function declaration 2939/// NewFD. This routine performs all semantic checking that does not 2940/// require the actual declarator involved in the declaration, and is 2941/// used both for the declaration of functions as they are parsed 2942/// (called via ActOnDeclarator) and for the declaration of functions 2943/// that have been instantiated via C++ template instantiation (called 2944/// via InstantiateDecl). 2945/// 2946/// \param IsExplicitSpecialiation whether this new function declaration is 2947/// an explicit specialization of the previous declaration. 2948/// 2949/// This sets NewFD->isInvalidDecl() to true if there was an error. 2950void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2951 bool IsExplicitSpecialization, 2952 bool &Redeclaration, 2953 bool &OverloadableAttrRequired) { 2954 // If NewFD is already known erroneous, don't do any of this checking. 2955 if (NewFD->isInvalidDecl()) 2956 return; 2957 2958 if (NewFD->getResultType()->isVariablyModifiedType()) { 2959 // Functions returning a variably modified type violate C99 6.7.5.2p2 2960 // because all functions have linkage. 2961 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2962 return NewFD->setInvalidDecl(); 2963 } 2964 2965 if (NewFD->isMain()) 2966 CheckMain(NewFD); 2967 2968 // Check for a previous declaration of this name. 2969 if (!PrevDecl && NewFD->isExternC()) { 2970 // Since we did not find anything by this name and we're declaring 2971 // an extern "C" function, look for a non-visible extern "C" 2972 // declaration with the same name. 2973 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2974 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2975 if (Pos != LocallyScopedExternalDecls.end()) 2976 PrevDecl = Pos->second; 2977 } 2978 2979 // Merge or overload the declaration with an existing declaration of 2980 // the same name, if appropriate. 2981 if (PrevDecl) { 2982 // Determine whether NewFD is an overload of PrevDecl or 2983 // a declaration that requires merging. If it's an overload, 2984 // there's no more work to do here; we'll just add the new 2985 // function to the scope. 2986 OverloadedFunctionDecl::function_iterator MatchedDecl; 2987 2988 if (!getLangOptions().CPlusPlus && 2989 AllowOverloadingOfFunction(PrevDecl, Context)) { 2990 OverloadableAttrRequired = true; 2991 2992 // Functions marked "overloadable" must have a prototype (that 2993 // we can't get through declaration merging). 2994 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2995 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2996 << NewFD; 2997 Redeclaration = true; 2998 2999 // Turn this into a variadic function with no parameters. 3000 QualType R = Context.getFunctionType( 3001 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3002 0, 0, true, 0); 3003 NewFD->setType(R); 3004 return NewFD->setInvalidDecl(); 3005 } 3006 } 3007 3008 if (PrevDecl && 3009 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3010 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3011 Redeclaration = true; 3012 Decl *OldDecl = PrevDecl; 3013 3014 // If PrevDecl was an overloaded function, extract the 3015 // FunctionDecl that matched. 3016 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3017 OldDecl = *MatchedDecl; 3018 3019 // NewFD and OldDecl represent declarations that need to be 3020 // merged. 3021 if (MergeFunctionDecl(NewFD, OldDecl)) 3022 return NewFD->setInvalidDecl(); 3023 3024 if (FunctionTemplateDecl *OldTemplateDecl 3025 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3026 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3027 FunctionTemplateDecl *NewTemplateDecl 3028 = NewFD->getDescribedFunctionTemplate(); 3029 assert(NewTemplateDecl && "Template/non-template mismatch"); 3030 if (CXXMethodDecl *Method 3031 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3032 Method->setAccess(OldTemplateDecl->getAccess()); 3033 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3034 } 3035 3036 // If this is an explicit specialization of a member that is a function 3037 // template, mark it as a member specialization. 3038 if (IsExplicitSpecialization && 3039 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3040 NewTemplateDecl->setMemberSpecialization(); 3041 assert(OldTemplateDecl->isMemberSpecialization()); 3042 } 3043 } else { 3044 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3045 NewFD->setAccess(OldDecl->getAccess()); 3046 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3047 } 3048 } 3049 } 3050 3051 // Semantic checking for this function declaration (in isolation). 3052 if (getLangOptions().CPlusPlus) { 3053 // C++-specific checks. 3054 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3055 CheckConstructor(Constructor); 3056 } else if (isa<CXXDestructorDecl>(NewFD)) { 3057 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3058 QualType ClassType = Context.getTypeDeclType(Record); 3059 if (!ClassType->isDependentType()) { 3060 DeclarationName Name 3061 = Context.DeclarationNames.getCXXDestructorName( 3062 Context.getCanonicalType(ClassType)); 3063 if (NewFD->getDeclName() != Name) { 3064 Diag(NewFD->getLocation(), diag::err_destructor_name); 3065 return NewFD->setInvalidDecl(); 3066 } 3067 } 3068 Record->setUserDeclaredDestructor(true); 3069 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3070 // user-defined destructor. 3071 Record->setPOD(false); 3072 3073 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3074 // declared destructor. 3075 // FIXME: C++0x: don't do this for "= default" destructors 3076 Record->setHasTrivialDestructor(false); 3077 } else if (CXXConversionDecl *Conversion 3078 = dyn_cast<CXXConversionDecl>(NewFD)) 3079 ActOnConversionDeclarator(Conversion); 3080 3081 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3082 if (NewFD->isOverloadedOperator() && 3083 CheckOverloadedOperatorDeclaration(NewFD)) 3084 return NewFD->setInvalidDecl(); 3085 3086 // In C++, check default arguments now that we have merged decls. Unless 3087 // the lexical context is the class, because in this case this is done 3088 // during delayed parsing anyway. 3089 if (!CurContext->isRecord()) 3090 CheckCXXDefaultArguments(NewFD); 3091 } 3092} 3093 3094void Sema::CheckMain(FunctionDecl* FD) { 3095 // C++ [basic.start.main]p3: A program that declares main to be inline 3096 // or static is ill-formed. 3097 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3098 // shall not appear in a declaration of main. 3099 // static main is not an error under C99, but we should warn about it. 3100 bool isInline = FD->isInline(); 3101 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3102 if (isInline || isStatic) { 3103 unsigned diagID = diag::warn_unusual_main_decl; 3104 if (isInline || getLangOptions().CPlusPlus) 3105 diagID = diag::err_unusual_main_decl; 3106 3107 int which = isStatic + (isInline << 1) - 1; 3108 Diag(FD->getLocation(), diagID) << which; 3109 } 3110 3111 QualType T = FD->getType(); 3112 assert(T->isFunctionType() && "function decl is not of function type"); 3113 const FunctionType* FT = T->getAs<FunctionType>(); 3114 3115 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3116 // TODO: add a replacement fixit to turn the return type into 'int'. 3117 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3118 FD->setInvalidDecl(true); 3119 } 3120 3121 // Treat protoless main() as nullary. 3122 if (isa<FunctionNoProtoType>(FT)) return; 3123 3124 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3125 unsigned nparams = FTP->getNumArgs(); 3126 assert(FD->getNumParams() == nparams); 3127 3128 if (nparams > 3) { 3129 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3130 FD->setInvalidDecl(true); 3131 nparams = 3; 3132 } 3133 3134 // FIXME: a lot of the following diagnostics would be improved 3135 // if we had some location information about types. 3136 3137 QualType CharPP = 3138 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3139 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3140 3141 for (unsigned i = 0; i < nparams; ++i) { 3142 QualType AT = FTP->getArgType(i); 3143 3144 bool mismatch = true; 3145 3146 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3147 mismatch = false; 3148 else if (Expected[i] == CharPP) { 3149 // As an extension, the following forms are okay: 3150 // char const ** 3151 // char const * const * 3152 // char * const * 3153 3154 QualifierCollector qs; 3155 const PointerType* PT; 3156 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3157 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3158 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3159 qs.removeConst(); 3160 mismatch = !qs.empty(); 3161 } 3162 } 3163 3164 if (mismatch) { 3165 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3166 // TODO: suggest replacing given type with expected type 3167 FD->setInvalidDecl(true); 3168 } 3169 } 3170 3171 if (nparams == 1 && !FD->isInvalidDecl()) { 3172 Diag(FD->getLocation(), diag::warn_main_one_arg); 3173 } 3174} 3175 3176bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3177 // FIXME: Need strict checking. In C89, we need to check for 3178 // any assignment, increment, decrement, function-calls, or 3179 // commas outside of a sizeof. In C99, it's the same list, 3180 // except that the aforementioned are allowed in unevaluated 3181 // expressions. Everything else falls under the 3182 // "may accept other forms of constant expressions" exception. 3183 // (We never end up here for C++, so the constant expression 3184 // rules there don't matter.) 3185 if (Init->isConstantInitializer(Context)) 3186 return false; 3187 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3188 << Init->getSourceRange(); 3189 return true; 3190} 3191 3192void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3193 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3194} 3195 3196/// AddInitializerToDecl - Adds the initializer Init to the 3197/// declaration dcl. If DirectInit is true, this is C++ direct 3198/// initialization rather than copy initialization. 3199void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3200 Decl *RealDecl = dcl.getAs<Decl>(); 3201 // If there is no declaration, there was an error parsing it. Just ignore 3202 // the initializer. 3203 if (RealDecl == 0) 3204 return; 3205 3206 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3207 // With declarators parsed the way they are, the parser cannot 3208 // distinguish between a normal initializer and a pure-specifier. 3209 // Thus this grotesque test. 3210 IntegerLiteral *IL; 3211 Expr *Init = static_cast<Expr *>(init.get()); 3212 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3213 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3214 if (Method->isVirtualAsWritten()) { 3215 Method->setPure(); 3216 3217 // A class is abstract if at least one function is pure virtual. 3218 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3219 } else if (!Method->isInvalidDecl()) { 3220 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3221 << Method->getDeclName() << Init->getSourceRange(); 3222 Method->setInvalidDecl(); 3223 } 3224 } else { 3225 Diag(Method->getLocation(), diag::err_member_function_initialization) 3226 << Method->getDeclName() << Init->getSourceRange(); 3227 Method->setInvalidDecl(); 3228 } 3229 return; 3230 } 3231 3232 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3233 if (!VDecl) { 3234 if (getLangOptions().CPlusPlus && 3235 RealDecl->getLexicalDeclContext()->isRecord() && 3236 isa<NamedDecl>(RealDecl)) 3237 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3238 << cast<NamedDecl>(RealDecl)->getDeclName(); 3239 else 3240 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3241 RealDecl->setInvalidDecl(); 3242 return; 3243 } 3244 3245 if (!VDecl->getType()->isArrayType() && 3246 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3247 diag::err_typecheck_decl_incomplete_type)) { 3248 RealDecl->setInvalidDecl(); 3249 return; 3250 } 3251 3252 const VarDecl *Def = 0; 3253 if (VDecl->getDefinition(Def)) { 3254 Diag(VDecl->getLocation(), diag::err_redefinition) 3255 << VDecl->getDeclName(); 3256 Diag(Def->getLocation(), diag::note_previous_definition); 3257 VDecl->setInvalidDecl(); 3258 return; 3259 } 3260 3261 // Take ownership of the expression, now that we're sure we have somewhere 3262 // to put it. 3263 Expr *Init = init.takeAs<Expr>(); 3264 assert(Init && "missing initializer"); 3265 3266 // Get the decls type and save a reference for later, since 3267 // CheckInitializerTypes may change it. 3268 QualType DclT = VDecl->getType(), SavT = DclT; 3269 if (VDecl->isBlockVarDecl()) { 3270 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3271 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3272 VDecl->setInvalidDecl(); 3273 } else if (!VDecl->isInvalidDecl()) { 3274 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3275 VDecl->getDeclName(), DirectInit)) 3276 VDecl->setInvalidDecl(); 3277 3278 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3279 // Don't check invalid declarations to avoid emitting useless diagnostics. 3280 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3281 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3282 CheckForConstantInitializer(Init, DclT); 3283 } 3284 } 3285 } else if (VDecl->isStaticDataMember() && 3286 VDecl->getLexicalDeclContext()->isRecord()) { 3287 // This is an in-class initialization for a static data member, e.g., 3288 // 3289 // struct S { 3290 // static const int value = 17; 3291 // }; 3292 3293 // Attach the initializer 3294 VDecl->setInit(Context, Init); 3295 3296 // C++ [class.mem]p4: 3297 // A member-declarator can contain a constant-initializer only 3298 // if it declares a static member (9.4) of const integral or 3299 // const enumeration type, see 9.4.2. 3300 QualType T = VDecl->getType(); 3301 if (!T->isDependentType() && 3302 (!Context.getCanonicalType(T).isConstQualified() || 3303 !T->isIntegralType())) { 3304 Diag(VDecl->getLocation(), diag::err_member_initialization) 3305 << VDecl->getDeclName() << Init->getSourceRange(); 3306 VDecl->setInvalidDecl(); 3307 } else { 3308 // C++ [class.static.data]p4: 3309 // If a static data member is of const integral or const 3310 // enumeration type, its declaration in the class definition 3311 // can specify a constant-initializer which shall be an 3312 // integral constant expression (5.19). 3313 if (!Init->isTypeDependent() && 3314 !Init->getType()->isIntegralType()) { 3315 // We have a non-dependent, non-integral or enumeration type. 3316 Diag(Init->getSourceRange().getBegin(), 3317 diag::err_in_class_initializer_non_integral_type) 3318 << Init->getType() << Init->getSourceRange(); 3319 VDecl->setInvalidDecl(); 3320 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3321 // Check whether the expression is a constant expression. 3322 llvm::APSInt Value; 3323 SourceLocation Loc; 3324 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3325 Diag(Loc, diag::err_in_class_initializer_non_constant) 3326 << Init->getSourceRange(); 3327 VDecl->setInvalidDecl(); 3328 } else if (!VDecl->getType()->isDependentType()) 3329 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3330 } 3331 } 3332 } else if (VDecl->isFileVarDecl()) { 3333 if (VDecl->getStorageClass() == VarDecl::Extern) 3334 Diag(VDecl->getLocation(), diag::warn_extern_init); 3335 if (!VDecl->isInvalidDecl()) 3336 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3337 VDecl->getDeclName(), DirectInit)) 3338 VDecl->setInvalidDecl(); 3339 3340 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3341 // Don't check invalid declarations to avoid emitting useless diagnostics. 3342 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3343 // C99 6.7.8p4. All file scoped initializers need to be constant. 3344 CheckForConstantInitializer(Init, DclT); 3345 } 3346 } 3347 // If the type changed, it means we had an incomplete type that was 3348 // completed by the initializer. For example: 3349 // int ary[] = { 1, 3, 5 }; 3350 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3351 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3352 VDecl->setType(DclT); 3353 Init->setType(DclT); 3354 } 3355 3356 Init = MaybeCreateCXXExprWithTemporaries(Init, 3357 /*ShouldDestroyTemporaries=*/true); 3358 // Attach the initializer to the decl. 3359 VDecl->setInit(Context, Init); 3360 3361 // If the previous declaration of VDecl was a tentative definition, 3362 // remove it from the set of tentative definitions. 3363 if (VDecl->getPreviousDeclaration() && 3364 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3365 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3366 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3367 } 3368 3369 return; 3370} 3371 3372void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3373 bool TypeContainsUndeducedAuto) { 3374 Decl *RealDecl = dcl.getAs<Decl>(); 3375 3376 // If there is no declaration, there was an error parsing it. Just ignore it. 3377 if (RealDecl == 0) 3378 return; 3379 3380 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3381 QualType Type = Var->getType(); 3382 3383 // Record tentative definitions. 3384 if (Var->isTentativeDefinition(Context)) { 3385 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3386 InsertPair = 3387 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3388 3389 // Keep the latest definition in the map. If we see 'int i; int i;' we 3390 // want the second one in the map. 3391 InsertPair.first->second = Var; 3392 3393 // However, for the list, we don't care about the order, just make sure 3394 // that there are no dupes for a given declaration name. 3395 if (InsertPair.second) 3396 TentativeDefinitionList.push_back(Var->getDeclName()); 3397 } 3398 3399 // C++ [dcl.init.ref]p3: 3400 // The initializer can be omitted for a reference only in a 3401 // parameter declaration (8.3.5), in the declaration of a 3402 // function return type, in the declaration of a class member 3403 // within its class declaration (9.2), and where the extern 3404 // specifier is explicitly used. 3405 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3406 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3407 << Var->getDeclName() 3408 << SourceRange(Var->getLocation(), Var->getLocation()); 3409 Var->setInvalidDecl(); 3410 return; 3411 } 3412 3413 // C++0x [dcl.spec.auto]p3 3414 if (TypeContainsUndeducedAuto) { 3415 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3416 << Var->getDeclName() << Type; 3417 Var->setInvalidDecl(); 3418 return; 3419 } 3420 3421 // C++ [temp.expl.spec]p15: 3422 // An explicit specialization of a static data member of a template is a 3423 // definition if the declaration includes an initializer; otherwise, it 3424 // is a declaration. 3425 if (Var->isStaticDataMember() && 3426 Var->getInstantiatedFromStaticDataMember() && 3427 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3428 return; 3429 3430 // C++ [dcl.init]p9: 3431 // If no initializer is specified for an object, and the object 3432 // is of (possibly cv-qualified) non-POD class type (or array 3433 // thereof), the object shall be default-initialized; if the 3434 // object is of const-qualified type, the underlying class type 3435 // shall have a user-declared default constructor. 3436 // 3437 // FIXME: Diagnose the "user-declared default constructor" bit. 3438 if (getLangOptions().CPlusPlus) { 3439 QualType InitType = Type; 3440 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3441 InitType = Array->getElementType(); 3442 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3443 InitType->isRecordType() && !InitType->isDependentType()) { 3444 if (!RequireCompleteType(Var->getLocation(), InitType, 3445 diag::err_invalid_incomplete_type_use)) { 3446 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3447 3448 CXXConstructorDecl *Constructor 3449 = PerformInitializationByConstructor(InitType, 3450 MultiExprArg(*this, 0, 0), 3451 Var->getLocation(), 3452 SourceRange(Var->getLocation(), 3453 Var->getLocation()), 3454 Var->getDeclName(), 3455 IK_Default, 3456 ConstructorArgs); 3457 3458 // FIXME: Location info for the variable initialization? 3459 if (!Constructor) 3460 Var->setInvalidDecl(); 3461 else { 3462 // FIXME: Cope with initialization of arrays 3463 if (!Constructor->isTrivial() && 3464 InitializeVarWithConstructor(Var, Constructor, InitType, 3465 move_arg(ConstructorArgs))) 3466 Var->setInvalidDecl(); 3467 3468 FinalizeVarWithDestructor(Var, InitType); 3469 } 3470 } else { 3471 Var->setInvalidDecl(); 3472 } 3473 } 3474 } 3475 3476#if 0 3477 // FIXME: Temporarily disabled because we are not properly parsing 3478 // linkage specifications on declarations, e.g., 3479 // 3480 // extern "C" const CGPoint CGPointerZero; 3481 // 3482 // C++ [dcl.init]p9: 3483 // 3484 // If no initializer is specified for an object, and the 3485 // object is of (possibly cv-qualified) non-POD class type (or 3486 // array thereof), the object shall be default-initialized; if 3487 // the object is of const-qualified type, the underlying class 3488 // type shall have a user-declared default 3489 // constructor. Otherwise, if no initializer is specified for 3490 // an object, the object and its subobjects, if any, have an 3491 // indeterminate initial value; if the object or any of its 3492 // subobjects are of const-qualified type, the program is 3493 // ill-formed. 3494 // 3495 // This isn't technically an error in C, so we don't diagnose it. 3496 // 3497 // FIXME: Actually perform the POD/user-defined default 3498 // constructor check. 3499 if (getLangOptions().CPlusPlus && 3500 Context.getCanonicalType(Type).isConstQualified() && 3501 !Var->hasExternalStorage()) 3502 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3503 << Var->getName() 3504 << SourceRange(Var->getLocation(), Var->getLocation()); 3505#endif 3506 } 3507} 3508 3509Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3510 DeclPtrTy *Group, 3511 unsigned NumDecls) { 3512 llvm::SmallVector<Decl*, 8> Decls; 3513 3514 if (DS.isTypeSpecOwned()) 3515 Decls.push_back((Decl*)DS.getTypeRep()); 3516 3517 for (unsigned i = 0; i != NumDecls; ++i) 3518 if (Decl *D = Group[i].getAs<Decl>()) 3519 Decls.push_back(D); 3520 3521 // Perform semantic analysis that depends on having fully processed both 3522 // the declarator and initializer. 3523 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3524 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3525 if (!IDecl) 3526 continue; 3527 QualType T = IDecl->getType(); 3528 3529 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3530 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3531 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3532 if (T->isDependentType()) { 3533 // If T is dependent, we should not require a complete type. 3534 // (RequireCompleteType shouldn't be called with dependent types.) 3535 // But we still can at least check if we've got an array of unspecified 3536 // size without an initializer. 3537 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3538 !IDecl->getInit()) { 3539 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3540 << T; 3541 IDecl->setInvalidDecl(); 3542 } 3543 } else if (!IDecl->isInvalidDecl()) { 3544 // If T is an incomplete array type with an initializer list that is 3545 // dependent on something, its size has not been fixed. We could attempt 3546 // to fix the size for such arrays, but we would still have to check 3547 // here for initializers containing a C++0x vararg expansion, e.g. 3548 // template <typename... Args> void f(Args... args) { 3549 // int vals[] = { args }; 3550 // } 3551 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3552 Expr *Init = IDecl->getInit(); 3553 if (IAT && Init && 3554 (Init->isTypeDependent() || Init->isValueDependent())) { 3555 // Check that the member type of the array is complete, at least. 3556 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3557 diag::err_typecheck_decl_incomplete_type)) 3558 IDecl->setInvalidDecl(); 3559 } else if (RequireCompleteType(IDecl->getLocation(), T, 3560 diag::err_typecheck_decl_incomplete_type)) 3561 IDecl->setInvalidDecl(); 3562 } 3563 } 3564 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3565 // object that has file scope without an initializer, and without a 3566 // storage-class specifier or with the storage-class specifier "static", 3567 // constitutes a tentative definition. Note: A tentative definition with 3568 // external linkage is valid (C99 6.2.2p5). 3569 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3570 if (const IncompleteArrayType *ArrayT 3571 = Context.getAsIncompleteArrayType(T)) { 3572 if (RequireCompleteType(IDecl->getLocation(), 3573 ArrayT->getElementType(), 3574 diag::err_illegal_decl_array_incomplete_type)) 3575 IDecl->setInvalidDecl(); 3576 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3577 // C99 6.9.2p3: If the declaration of an identifier for an object is 3578 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3579 // declared type shall not be an incomplete type. 3580 // NOTE: code such as the following 3581 // static struct s; 3582 // struct s { int a; }; 3583 // is accepted by gcc. Hence here we issue a warning instead of 3584 // an error and we do not invalidate the static declaration. 3585 // NOTE: to avoid multiple warnings, only check the first declaration. 3586 if (IDecl->getPreviousDeclaration() == 0) 3587 RequireCompleteType(IDecl->getLocation(), T, 3588 diag::ext_typecheck_decl_incomplete_type); 3589 } 3590 } 3591 } 3592 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3593 Decls.data(), Decls.size())); 3594} 3595 3596 3597/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3598/// to introduce parameters into function prototype scope. 3599Sema::DeclPtrTy 3600Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3601 const DeclSpec &DS = D.getDeclSpec(); 3602 3603 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3604 VarDecl::StorageClass StorageClass = VarDecl::None; 3605 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3606 StorageClass = VarDecl::Register; 3607 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3608 Diag(DS.getStorageClassSpecLoc(), 3609 diag::err_invalid_storage_class_in_func_decl); 3610 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3611 } 3612 3613 if (D.getDeclSpec().isThreadSpecified()) 3614 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3615 3616 DiagnoseFunctionSpecifiers(D); 3617 3618 // Check that there are no default arguments inside the type of this 3619 // parameter (C++ only). 3620 if (getLangOptions().CPlusPlus) 3621 CheckExtraCXXDefaultArguments(D); 3622 3623 DeclaratorInfo *DInfo = 0; 3624 TagDecl *OwnedDecl = 0; 3625 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3626 &OwnedDecl); 3627 3628 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3629 // C++ [dcl.fct]p6: 3630 // Types shall not be defined in return or parameter types. 3631 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3632 << Context.getTypeDeclType(OwnedDecl); 3633 } 3634 3635 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3636 // Can this happen for params? We already checked that they don't conflict 3637 // among each other. Here they can only shadow globals, which is ok. 3638 IdentifierInfo *II = D.getIdentifier(); 3639 if (II) { 3640 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3641 if (PrevDecl->isTemplateParameter()) { 3642 // Maybe we will complain about the shadowed template parameter. 3643 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3644 // Just pretend that we didn't see the previous declaration. 3645 PrevDecl = 0; 3646 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3647 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3648 3649 // Recover by removing the name 3650 II = 0; 3651 D.SetIdentifier(0, D.getIdentifierLoc()); 3652 } 3653 } 3654 } 3655 3656 // Parameters can not be abstract class types. 3657 // For record types, this is done by the AbstractClassUsageDiagnoser once 3658 // the class has been completely parsed. 3659 if (!CurContext->isRecord() && 3660 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3661 diag::err_abstract_type_in_decl, 3662 AbstractParamType)) 3663 D.setInvalidType(true); 3664 3665 QualType T = adjustParameterType(parmDeclType); 3666 3667 ParmVarDecl *New; 3668 if (T == parmDeclType) // parameter type did not need adjustment 3669 New = ParmVarDecl::Create(Context, CurContext, 3670 D.getIdentifierLoc(), II, 3671 parmDeclType, DInfo, StorageClass, 3672 0); 3673 else // keep track of both the adjusted and unadjusted types 3674 New = OriginalParmVarDecl::Create(Context, CurContext, 3675 D.getIdentifierLoc(), II, T, DInfo, 3676 parmDeclType, StorageClass, 0); 3677 3678 if (D.isInvalidType()) 3679 New->setInvalidDecl(); 3680 3681 // Parameter declarators cannot be interface types. All ObjC objects are 3682 // passed by reference. 3683 if (T->isObjCInterfaceType()) { 3684 Diag(D.getIdentifierLoc(), 3685 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3686 New->setInvalidDecl(); 3687 } 3688 3689 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3690 if (D.getCXXScopeSpec().isSet()) { 3691 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3692 << D.getCXXScopeSpec().getRange(); 3693 New->setInvalidDecl(); 3694 } 3695 3696 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3697 // duration shall not be qualified by an address-space qualifier." 3698 // Since all parameters have automatic store duration, they can not have 3699 // an address space. 3700 if (T.getAddressSpace() != 0) { 3701 Diag(D.getIdentifierLoc(), 3702 diag::err_arg_with_address_space); 3703 New->setInvalidDecl(); 3704 } 3705 3706 3707 // Add the parameter declaration into this scope. 3708 S->AddDecl(DeclPtrTy::make(New)); 3709 if (II) 3710 IdResolver.AddDecl(New); 3711 3712 ProcessDeclAttributes(S, New, D); 3713 3714 if (New->hasAttr<BlocksAttr>()) { 3715 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3716 } 3717 return DeclPtrTy::make(New); 3718} 3719 3720void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3721 SourceLocation LocAfterDecls) { 3722 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3723 "Not a function declarator!"); 3724 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3725 3726 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3727 // for a K&R function. 3728 if (!FTI.hasPrototype) { 3729 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3730 --i; 3731 if (FTI.ArgInfo[i].Param == 0) { 3732 llvm::SmallString<256> Code; 3733 llvm::raw_svector_ostream(Code) << " int " 3734 << FTI.ArgInfo[i].Ident->getName() 3735 << ";\n"; 3736 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3737 << FTI.ArgInfo[i].Ident 3738 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3739 3740 // Implicitly declare the argument as type 'int' for lack of a better 3741 // type. 3742 DeclSpec DS; 3743 const char* PrevSpec; // unused 3744 unsigned DiagID; // unused 3745 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3746 PrevSpec, DiagID); 3747 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3748 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3749 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3750 } 3751 } 3752 } 3753} 3754 3755Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3756 Declarator &D) { 3757 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3758 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3759 "Not a function declarator!"); 3760 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3761 3762 if (FTI.hasPrototype) { 3763 // FIXME: Diagnose arguments without names in C. 3764 } 3765 3766 Scope *ParentScope = FnBodyScope->getParent(); 3767 3768 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3769 MultiTemplateParamsArg(*this), 3770 /*IsFunctionDefinition=*/true); 3771 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3772} 3773 3774Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3775 if (!D) 3776 return D; 3777 FunctionDecl *FD = 0; 3778 3779 if (FunctionTemplateDecl *FunTmpl 3780 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3781 FD = FunTmpl->getTemplatedDecl(); 3782 else 3783 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3784 3785 CurFunctionNeedsScopeChecking = false; 3786 3787 // See if this is a redefinition. 3788 const FunctionDecl *Definition; 3789 if (FD->getBody(Definition)) { 3790 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3791 Diag(Definition->getLocation(), diag::note_previous_definition); 3792 } 3793 3794 // Builtin functions cannot be defined. 3795 if (unsigned BuiltinID = FD->getBuiltinID()) { 3796 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3797 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3798 FD->setInvalidDecl(); 3799 } 3800 } 3801 3802 // The return type of a function definition must be complete 3803 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3804 QualType ResultType = FD->getResultType(); 3805 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3806 !FD->isInvalidDecl() && 3807 RequireCompleteType(FD->getLocation(), ResultType, 3808 diag::err_func_def_incomplete_result)) 3809 FD->setInvalidDecl(); 3810 3811 // GNU warning -Wmissing-prototypes: 3812 // Warn if a global function is defined without a previous 3813 // prototype declaration. This warning is issued even if the 3814 // definition itself provides a prototype. The aim is to detect 3815 // global functions that fail to be declared in header files. 3816 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3817 !FD->isMain()) { 3818 bool MissingPrototype = true; 3819 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3820 Prev; Prev = Prev->getPreviousDeclaration()) { 3821 // Ignore any declarations that occur in function or method 3822 // scope, because they aren't visible from the header. 3823 if (Prev->getDeclContext()->isFunctionOrMethod()) 3824 continue; 3825 3826 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3827 break; 3828 } 3829 3830 if (MissingPrototype) 3831 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3832 } 3833 3834 if (FnBodyScope) 3835 PushDeclContext(FnBodyScope, FD); 3836 3837 // Check the validity of our function parameters 3838 CheckParmsForFunctionDef(FD); 3839 3840 // Introduce our parameters into the function scope 3841 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3842 ParmVarDecl *Param = FD->getParamDecl(p); 3843 Param->setOwningFunction(FD); 3844 3845 // If this has an identifier, add it to the scope stack. 3846 if (Param->getIdentifier() && FnBodyScope) 3847 PushOnScopeChains(Param, FnBodyScope); 3848 } 3849 3850 // Checking attributes of current function definition 3851 // dllimport attribute. 3852 if (FD->getAttr<DLLImportAttr>() && 3853 (!FD->getAttr<DLLExportAttr>())) { 3854 // dllimport attribute cannot be applied to definition. 3855 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3856 Diag(FD->getLocation(), 3857 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3858 << "dllimport"; 3859 FD->setInvalidDecl(); 3860 return DeclPtrTy::make(FD); 3861 } else { 3862 // If a symbol previously declared dllimport is later defined, the 3863 // attribute is ignored in subsequent references, and a warning is 3864 // emitted. 3865 Diag(FD->getLocation(), 3866 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3867 << FD->getNameAsCString() << "dllimport"; 3868 } 3869 } 3870 return DeclPtrTy::make(FD); 3871} 3872 3873Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3874 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3875} 3876 3877Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3878 bool IsInstantiation) { 3879 Decl *dcl = D.getAs<Decl>(); 3880 Stmt *Body = BodyArg.takeAs<Stmt>(); 3881 3882 FunctionDecl *FD = 0; 3883 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3884 if (FunTmpl) 3885 FD = FunTmpl->getTemplatedDecl(); 3886 else 3887 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3888 3889 if (FD) { 3890 FD->setBody(Body); 3891 if (FD->isMain()) 3892 // C and C++ allow for main to automagically return 0. 3893 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3894 FD->setHasImplicitReturnZero(true); 3895 else 3896 CheckFallThroughForFunctionDef(FD, Body); 3897 3898 if (!FD->isInvalidDecl()) 3899 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3900 3901 // C++ [basic.def.odr]p2: 3902 // [...] A virtual member function is used if it is not pure. [...] 3903 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3904 if (Method->isVirtual() && !Method->isPure()) 3905 MarkDeclarationReferenced(Method->getLocation(), Method); 3906 3907 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3908 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3909 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3910 MD->setBody(Body); 3911 CheckFallThroughForFunctionDef(MD, Body); 3912 MD->setEndLoc(Body->getLocEnd()); 3913 3914 if (!MD->isInvalidDecl()) 3915 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3916 } else { 3917 Body->Destroy(Context); 3918 return DeclPtrTy(); 3919 } 3920 if (!IsInstantiation) 3921 PopDeclContext(); 3922 3923 // Verify and clean out per-function state. 3924 3925 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3926 3927 // Check goto/label use. 3928 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3929 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3930 LabelStmt *L = I->second; 3931 3932 // Verify that we have no forward references left. If so, there was a goto 3933 // or address of a label taken, but no definition of it. Label fwd 3934 // definitions are indicated with a null substmt. 3935 if (L->getSubStmt() != 0) 3936 continue; 3937 3938 // Emit error. 3939 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3940 3941 // At this point, we have gotos that use the bogus label. Stitch it into 3942 // the function body so that they aren't leaked and that the AST is well 3943 // formed. 3944 if (Body == 0) { 3945 // The whole function wasn't parsed correctly, just delete this. 3946 L->Destroy(Context); 3947 continue; 3948 } 3949 3950 // Otherwise, the body is valid: we want to stitch the label decl into the 3951 // function somewhere so that it is properly owned and so that the goto 3952 // has a valid target. Do this by creating a new compound stmt with the 3953 // label in it. 3954 3955 // Give the label a sub-statement. 3956 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3957 3958 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3959 cast<CXXTryStmt>(Body)->getTryBlock() : 3960 cast<CompoundStmt>(Body); 3961 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3962 Elements.push_back(L); 3963 Compound->setStmts(Context, &Elements[0], Elements.size()); 3964 } 3965 FunctionLabelMap.clear(); 3966 3967 if (!Body) return D; 3968 3969 // Verify that that gotos and switch cases don't jump into scopes illegally. 3970 if (CurFunctionNeedsScopeChecking) 3971 DiagnoseInvalidJumps(Body); 3972 3973 // C++ constructors that have function-try-blocks can't have return 3974 // statements in the handlers of that block. (C++ [except.handle]p14) 3975 // Verify this. 3976 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3977 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3978 3979 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3980 computeBaseOrMembersToDestroy(Destructor); 3981 return D; 3982} 3983 3984/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3985/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3986NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3987 IdentifierInfo &II, Scope *S) { 3988 // Before we produce a declaration for an implicitly defined 3989 // function, see whether there was a locally-scoped declaration of 3990 // this name as a function or variable. If so, use that 3991 // (non-visible) declaration, and complain about it. 3992 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3993 = LocallyScopedExternalDecls.find(&II); 3994 if (Pos != LocallyScopedExternalDecls.end()) { 3995 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3996 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3997 return Pos->second; 3998 } 3999 4000 // Extension in C99. Legal in C90, but warn about it. 4001 if (II.getName().startswith("__builtin_")) 4002 Diag(Loc, diag::warn_builtin_unknown) << &II; 4003 else if (getLangOptions().C99) 4004 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4005 else 4006 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4007 4008 // Set a Declarator for the implicit definition: int foo(); 4009 const char *Dummy; 4010 DeclSpec DS; 4011 unsigned DiagID; 4012 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4013 Error = Error; // Silence warning. 4014 assert(!Error && "Error setting up implicit decl!"); 4015 Declarator D(DS, Declarator::BlockContext); 4016 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4017 0, 0, false, SourceLocation(), 4018 false, 0,0,0, Loc, Loc, D), 4019 SourceLocation()); 4020 D.SetIdentifier(&II, Loc); 4021 4022 // Insert this function into translation-unit scope. 4023 4024 DeclContext *PrevDC = CurContext; 4025 CurContext = Context.getTranslationUnitDecl(); 4026 4027 FunctionDecl *FD = 4028 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4029 FD->setImplicit(); 4030 4031 CurContext = PrevDC; 4032 4033 AddKnownFunctionAttributes(FD); 4034 4035 return FD; 4036} 4037 4038/// \brief Adds any function attributes that we know a priori based on 4039/// the declaration of this function. 4040/// 4041/// These attributes can apply both to implicitly-declared builtins 4042/// (like __builtin___printf_chk) or to library-declared functions 4043/// like NSLog or printf. 4044void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4045 if (FD->isInvalidDecl()) 4046 return; 4047 4048 // If this is a built-in function, map its builtin attributes to 4049 // actual attributes. 4050 if (unsigned BuiltinID = FD->getBuiltinID()) { 4051 // Handle printf-formatting attributes. 4052 unsigned FormatIdx; 4053 bool HasVAListArg; 4054 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4055 if (!FD->getAttr<FormatAttr>()) 4056 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4057 HasVAListArg ? 0 : FormatIdx + 2)); 4058 } 4059 4060 // Mark const if we don't care about errno and that is the only 4061 // thing preventing the function from being const. This allows 4062 // IRgen to use LLVM intrinsics for such functions. 4063 if (!getLangOptions().MathErrno && 4064 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4065 if (!FD->getAttr<ConstAttr>()) 4066 FD->addAttr(::new (Context) ConstAttr()); 4067 } 4068 4069 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4070 FD->addAttr(::new (Context) NoReturnAttr()); 4071 } 4072 4073 IdentifierInfo *Name = FD->getIdentifier(); 4074 if (!Name) 4075 return; 4076 if ((!getLangOptions().CPlusPlus && 4077 FD->getDeclContext()->isTranslationUnit()) || 4078 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4079 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4080 LinkageSpecDecl::lang_c)) { 4081 // Okay: this could be a libc/libm/Objective-C function we know 4082 // about. 4083 } else 4084 return; 4085 4086 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4087 // FIXME: NSLog and NSLogv should be target specific 4088 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4089 // FIXME: We known better than our headers. 4090 const_cast<FormatAttr *>(Format)->setType("printf"); 4091 } else 4092 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4093 Name->isStr("NSLogv") ? 0 : 2)); 4094 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4095 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4096 // target-specific builtins, perhaps? 4097 if (!FD->getAttr<FormatAttr>()) 4098 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4099 Name->isStr("vasprintf") ? 0 : 3)); 4100 } 4101} 4102 4103TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 4104 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4105 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4106 4107 // Scope manipulation handled by caller. 4108 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4109 D.getIdentifierLoc(), 4110 D.getIdentifier(), 4111 T); 4112 4113 if (const TagType *TT = T->getAs<TagType>()) { 4114 TagDecl *TD = TT->getDecl(); 4115 4116 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4117 // keep track of the TypedefDecl. 4118 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4119 TD->setTypedefForAnonDecl(NewTD); 4120 } 4121 4122 if (D.isInvalidType()) 4123 NewTD->setInvalidDecl(); 4124 return NewTD; 4125} 4126 4127 4128/// \brief Determine whether a tag with a given kind is acceptable 4129/// as a redeclaration of the given tag declaration. 4130/// 4131/// \returns true if the new tag kind is acceptable, false otherwise. 4132bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4133 TagDecl::TagKind NewTag, 4134 SourceLocation NewTagLoc, 4135 const IdentifierInfo &Name) { 4136 // C++ [dcl.type.elab]p3: 4137 // The class-key or enum keyword present in the 4138 // elaborated-type-specifier shall agree in kind with the 4139 // declaration to which the name in theelaborated-type-specifier 4140 // refers. This rule also applies to the form of 4141 // elaborated-type-specifier that declares a class-name or 4142 // friend class since it can be construed as referring to the 4143 // definition of the class. Thus, in any 4144 // elaborated-type-specifier, the enum keyword shall be used to 4145 // refer to an enumeration (7.2), the union class-keyshall be 4146 // used to refer to a union (clause 9), and either the class or 4147 // struct class-key shall be used to refer to a class (clause 9) 4148 // declared using the class or struct class-key. 4149 TagDecl::TagKind OldTag = Previous->getTagKind(); 4150 if (OldTag == NewTag) 4151 return true; 4152 4153 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4154 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4155 // Warn about the struct/class tag mismatch. 4156 bool isTemplate = false; 4157 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4158 isTemplate = Record->getDescribedClassTemplate(); 4159 4160 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4161 << (NewTag == TagDecl::TK_class) 4162 << isTemplate << &Name 4163 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4164 OldTag == TagDecl::TK_class? "class" : "struct"); 4165 Diag(Previous->getLocation(), diag::note_previous_use); 4166 return true; 4167 } 4168 return false; 4169} 4170 4171/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4172/// former case, Name will be non-null. In the later case, Name will be null. 4173/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4174/// reference/declaration/definition of a tag. 4175Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4176 SourceLocation KWLoc, const CXXScopeSpec &SS, 4177 IdentifierInfo *Name, SourceLocation NameLoc, 4178 AttributeList *Attr, AccessSpecifier AS, 4179 MultiTemplateParamsArg TemplateParameterLists, 4180 bool &OwnedDecl, bool &IsDependent) { 4181 // If this is not a definition, it must have a name. 4182 assert((Name != 0 || TUK == TUK_Definition) && 4183 "Nameless record must be a definition!"); 4184 4185 OwnedDecl = false; 4186 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4187 4188 // FIXME: Check explicit specializations more carefully. 4189 bool isExplicitSpecialization = false; 4190 if (TUK != TUK_Reference) { 4191 if (TemplateParameterList *TemplateParams 4192 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4193 (TemplateParameterList**)TemplateParameterLists.get(), 4194 TemplateParameterLists.size(), 4195 isExplicitSpecialization)) { 4196 if (TemplateParams->size() > 0) { 4197 // This is a declaration or definition of a class template (which may 4198 // be a member of another template). 4199 OwnedDecl = false; 4200 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4201 SS, Name, NameLoc, Attr, 4202 TemplateParams, 4203 AS); 4204 TemplateParameterLists.release(); 4205 return Result.get(); 4206 } else { 4207 // The "template<>" header is extraneous. 4208 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4209 << ElaboratedType::getNameForTagKind(Kind) << Name; 4210 isExplicitSpecialization = true; 4211 } 4212 } 4213 4214 TemplateParameterLists.release(); 4215 } 4216 4217 DeclContext *SearchDC = CurContext; 4218 DeclContext *DC = CurContext; 4219 NamedDecl *PrevDecl = 0; 4220 bool isStdBadAlloc = false; 4221 bool Invalid = false; 4222 4223 bool RedeclarationOnly = (TUK != TUK_Reference); 4224 4225 if (Name && SS.isNotEmpty()) { 4226 // We have a nested-name tag ('struct foo::bar'). 4227 4228 // Check for invalid 'foo::'. 4229 if (SS.isInvalid()) { 4230 Name = 0; 4231 goto CreateNewDecl; 4232 } 4233 4234 // If this is a friend or a reference to a class in a dependent 4235 // context, don't try to make a decl for it. 4236 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4237 DC = computeDeclContext(SS, false); 4238 if (!DC) { 4239 IsDependent = true; 4240 return DeclPtrTy(); 4241 } 4242 } 4243 4244 if (RequireCompleteDeclContext(SS)) 4245 return DeclPtrTy::make((Decl *)0); 4246 4247 DC = computeDeclContext(SS, true); 4248 SearchDC = DC; 4249 // Look-up name inside 'foo::'. 4250 LookupResult R; 4251 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4252 4253 if (R.isAmbiguous()) { 4254 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4255 return DeclPtrTy(); 4256 } 4257 4258 if (R.getKind() == LookupResult::Found) 4259 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4260 4261 // A tag 'foo::bar' must already exist. 4262 if (!PrevDecl) { 4263 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4264 Name = 0; 4265 Invalid = true; 4266 goto CreateNewDecl; 4267 } 4268 } else if (Name) { 4269 // If this is a named struct, check to see if there was a previous forward 4270 // declaration or definition. 4271 // FIXME: We're looking into outer scopes here, even when we 4272 // shouldn't be. Doing so can result in ambiguities that we 4273 // shouldn't be diagnosing. 4274 LookupResult R; 4275 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4276 if (R.isAmbiguous()) { 4277 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4278 // FIXME: This is not best way to recover from case like: 4279 // 4280 // struct S s; 4281 // 4282 // causes needless "incomplete type" error later. 4283 Name = 0; 4284 PrevDecl = 0; 4285 Invalid = true; 4286 } else 4287 PrevDecl = R.getAsSingleDecl(Context); 4288 4289 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4290 // FIXME: This makes sure that we ignore the contexts associated 4291 // with C structs, unions, and enums when looking for a matching 4292 // tag declaration or definition. See the similar lookup tweak 4293 // in Sema::LookupName; is there a better way to deal with this? 4294 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4295 SearchDC = SearchDC->getParent(); 4296 } 4297 } 4298 4299 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4300 // Maybe we will complain about the shadowed template parameter. 4301 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4302 // Just pretend that we didn't see the previous declaration. 4303 PrevDecl = 0; 4304 } 4305 4306 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4307 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4308 // This is a declaration of or a reference to "std::bad_alloc". 4309 isStdBadAlloc = true; 4310 4311 if (!PrevDecl && StdBadAlloc) { 4312 // std::bad_alloc has been implicitly declared (but made invisible to 4313 // name lookup). Fill in this implicit declaration as the previous 4314 // declaration, so that the declarations get chained appropriately. 4315 PrevDecl = StdBadAlloc; 4316 } 4317 } 4318 4319 if (PrevDecl) { 4320 // Check whether the previous declaration is usable. 4321 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4322 4323 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4324 // If this is a use of a previous tag, or if the tag is already declared 4325 // in the same scope (so that the definition/declaration completes or 4326 // rementions the tag), reuse the decl. 4327 if (TUK == TUK_Reference || TUK == TUK_Friend || 4328 isDeclInScope(PrevDecl, SearchDC, S)) { 4329 // Make sure that this wasn't declared as an enum and now used as a 4330 // struct or something similar. 4331 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4332 bool SafeToContinue 4333 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4334 Kind != TagDecl::TK_enum); 4335 if (SafeToContinue) 4336 Diag(KWLoc, diag::err_use_with_wrong_tag) 4337 << Name 4338 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4339 PrevTagDecl->getKindName()); 4340 else 4341 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4342 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4343 4344 if (SafeToContinue) 4345 Kind = PrevTagDecl->getTagKind(); 4346 else { 4347 // Recover by making this an anonymous redefinition. 4348 Name = 0; 4349 PrevDecl = 0; 4350 Invalid = true; 4351 } 4352 } 4353 4354 if (!Invalid) { 4355 // If this is a use, just return the declaration we found. 4356 4357 // FIXME: In the future, return a variant or some other clue 4358 // for the consumer of this Decl to know it doesn't own it. 4359 // For our current ASTs this shouldn't be a problem, but will 4360 // need to be changed with DeclGroups. 4361 if (TUK == TUK_Reference || TUK == TUK_Friend) 4362 return DeclPtrTy::make(PrevDecl); 4363 4364 // Diagnose attempts to redefine a tag. 4365 if (TUK == TUK_Definition) { 4366 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4367 // If we're defining a specialization and the previous definition 4368 // is from an implicit instantiation, don't emit an error 4369 // here; we'll catch this in the general case below. 4370 if (!isExplicitSpecialization || 4371 !isa<CXXRecordDecl>(Def) || 4372 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4373 == TSK_ExplicitSpecialization) { 4374 Diag(NameLoc, diag::err_redefinition) << Name; 4375 Diag(Def->getLocation(), diag::note_previous_definition); 4376 // If this is a redefinition, recover by making this 4377 // struct be anonymous, which will make any later 4378 // references get the previous definition. 4379 Name = 0; 4380 PrevDecl = 0; 4381 Invalid = true; 4382 } 4383 } else { 4384 // If the type is currently being defined, complain 4385 // about a nested redefinition. 4386 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4387 if (Tag->isBeingDefined()) { 4388 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4389 Diag(PrevTagDecl->getLocation(), 4390 diag::note_previous_definition); 4391 Name = 0; 4392 PrevDecl = 0; 4393 Invalid = true; 4394 } 4395 } 4396 4397 // Okay, this is definition of a previously declared or referenced 4398 // tag PrevDecl. We're going to create a new Decl for it. 4399 } 4400 } 4401 // If we get here we have (another) forward declaration or we 4402 // have a definition. Just create a new decl. 4403 4404 } else { 4405 // If we get here, this is a definition of a new tag type in a nested 4406 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4407 // new decl/type. We set PrevDecl to NULL so that the entities 4408 // have distinct types. 4409 PrevDecl = 0; 4410 } 4411 // If we get here, we're going to create a new Decl. If PrevDecl 4412 // is non-NULL, it's a definition of the tag declared by 4413 // PrevDecl. If it's NULL, we have a new definition. 4414 } else { 4415 // PrevDecl is a namespace, template, or anything else 4416 // that lives in the IDNS_Tag identifier namespace. 4417 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4418 // The tag name clashes with a namespace name, issue an error and 4419 // recover by making this tag be anonymous. 4420 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4421 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4422 Name = 0; 4423 PrevDecl = 0; 4424 Invalid = true; 4425 } else { 4426 // The existing declaration isn't relevant to us; we're in a 4427 // new scope, so clear out the previous declaration. 4428 PrevDecl = 0; 4429 } 4430 } 4431 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4432 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4433 // C++ [basic.scope.pdecl]p5: 4434 // -- for an elaborated-type-specifier of the form 4435 // 4436 // class-key identifier 4437 // 4438 // if the elaborated-type-specifier is used in the 4439 // decl-specifier-seq or parameter-declaration-clause of a 4440 // function defined in namespace scope, the identifier is 4441 // declared as a class-name in the namespace that contains 4442 // the declaration; otherwise, except as a friend 4443 // declaration, the identifier is declared in the smallest 4444 // non-class, non-function-prototype scope that contains the 4445 // declaration. 4446 // 4447 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4448 // C structs and unions. 4449 // 4450 // GNU C also supports this behavior as part of its incomplete 4451 // enum types extension, while GNU C++ does not. 4452 // 4453 // Find the context where we'll be declaring the tag. 4454 // FIXME: We would like to maintain the current DeclContext as the 4455 // lexical context, 4456 while (SearchDC->isRecord()) 4457 SearchDC = SearchDC->getParent(); 4458 4459 // Find the scope where we'll be declaring the tag. 4460 while (S->isClassScope() || 4461 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4462 ((S->getFlags() & Scope::DeclScope) == 0) || 4463 (S->getEntity() && 4464 ((DeclContext *)S->getEntity())->isTransparentContext())) 4465 S = S->getParent(); 4466 4467 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4468 // C++ [namespace.memdef]p3: 4469 // If a friend declaration in a non-local class first declares a 4470 // class or function, the friend class or function is a member of 4471 // the innermost enclosing namespace. 4472 while (!SearchDC->isFileContext()) 4473 SearchDC = SearchDC->getParent(); 4474 4475 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4476 while (S->getEntity() != SearchDC) 4477 S = S->getParent(); 4478 } 4479 4480CreateNewDecl: 4481 4482 // If there is an identifier, use the location of the identifier as the 4483 // location of the decl, otherwise use the location of the struct/union 4484 // keyword. 4485 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4486 4487 // Otherwise, create a new declaration. If there is a previous 4488 // declaration of the same entity, the two will be linked via 4489 // PrevDecl. 4490 TagDecl *New; 4491 4492 if (Kind == TagDecl::TK_enum) { 4493 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4494 // enum X { A, B, C } D; D should chain to X. 4495 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4496 cast_or_null<EnumDecl>(PrevDecl)); 4497 // If this is an undefined enum, warn. 4498 if (TUK != TUK_Definition && !Invalid) { 4499 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4500 : diag::ext_forward_ref_enum; 4501 Diag(Loc, DK); 4502 } 4503 } else { 4504 // struct/union/class 4505 4506 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4507 // struct X { int A; } D; D should chain to X. 4508 if (getLangOptions().CPlusPlus) { 4509 // FIXME: Look for a way to use RecordDecl for simple structs. 4510 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4511 cast_or_null<CXXRecordDecl>(PrevDecl)); 4512 4513 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4514 StdBadAlloc = cast<CXXRecordDecl>(New); 4515 } else 4516 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4517 cast_or_null<RecordDecl>(PrevDecl)); 4518 } 4519 4520 if (Kind != TagDecl::TK_enum) { 4521 // Handle #pragma pack: if the #pragma pack stack has non-default 4522 // alignment, make up a packed attribute for this decl. These 4523 // attributes are checked when the ASTContext lays out the 4524 // structure. 4525 // 4526 // It is important for implementing the correct semantics that this 4527 // happen here (in act on tag decl). The #pragma pack stack is 4528 // maintained as a result of parser callbacks which can occur at 4529 // many points during the parsing of a struct declaration (because 4530 // the #pragma tokens are effectively skipped over during the 4531 // parsing of the struct). 4532 if (unsigned Alignment = getPragmaPackAlignment()) 4533 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4534 } 4535 4536 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4537 // C++ [dcl.typedef]p3: 4538 // [...] Similarly, in a given scope, a class or enumeration 4539 // shall not be declared with the same name as a typedef-name 4540 // that is declared in that scope and refers to a type other 4541 // than the class or enumeration itself. 4542 LookupResult Lookup; 4543 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4544 TypedefDecl *PrevTypedef = 0; 4545 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4546 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4547 4548 NamedDecl *PrevTypedefNamed = PrevTypedef; 4549 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4550 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4551 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4552 Diag(Loc, diag::err_tag_definition_of_typedef) 4553 << Context.getTypeDeclType(New) 4554 << PrevTypedef->getUnderlyingType(); 4555 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4556 Invalid = true; 4557 } 4558 } 4559 4560 // If this is a specialization of a member class (of a class template), 4561 // check the specialization. 4562 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4563 Invalid = true; 4564 4565 if (Invalid) 4566 New->setInvalidDecl(); 4567 4568 if (Attr) 4569 ProcessDeclAttributeList(S, New, Attr); 4570 4571 // If we're declaring or defining a tag in function prototype scope 4572 // in C, note that this type can only be used within the function. 4573 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4574 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4575 4576 // Set the lexical context. If the tag has a C++ scope specifier, the 4577 // lexical context will be different from the semantic context. 4578 New->setLexicalDeclContext(CurContext); 4579 4580 // Mark this as a friend decl if applicable. 4581 if (TUK == TUK_Friend) 4582 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4583 4584 // Set the access specifier. 4585 if (!Invalid && TUK != TUK_Friend) 4586 SetMemberAccessSpecifier(New, PrevDecl, AS); 4587 4588 if (TUK == TUK_Definition) 4589 New->startDefinition(); 4590 4591 // If this has an identifier, add it to the scope stack. 4592 if (TUK == TUK_Friend) { 4593 // We might be replacing an existing declaration in the lookup tables; 4594 // if so, borrow its access specifier. 4595 if (PrevDecl) 4596 New->setAccess(PrevDecl->getAccess()); 4597 4598 // Friend tag decls are visible in fairly strange ways. 4599 if (!CurContext->isDependentContext()) { 4600 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4601 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4602 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4603 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4604 } 4605 } else if (Name) { 4606 S = getNonFieldDeclScope(S); 4607 PushOnScopeChains(New, S); 4608 } else { 4609 CurContext->addDecl(New); 4610 } 4611 4612 // If this is the C FILE type, notify the AST context. 4613 if (IdentifierInfo *II = New->getIdentifier()) 4614 if (!New->isInvalidDecl() && 4615 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4616 II->isStr("FILE")) 4617 Context.setFILEDecl(New); 4618 4619 OwnedDecl = true; 4620 return DeclPtrTy::make(New); 4621} 4622 4623void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4624 AdjustDeclIfTemplate(TagD); 4625 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4626 4627 // Enter the tag context. 4628 PushDeclContext(S, Tag); 4629 4630 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4631 FieldCollector->StartClass(); 4632 4633 if (Record->getIdentifier()) { 4634 // C++ [class]p2: 4635 // [...] The class-name is also inserted into the scope of the 4636 // class itself; this is known as the injected-class-name. For 4637 // purposes of access checking, the injected-class-name is treated 4638 // as if it were a public member name. 4639 CXXRecordDecl *InjectedClassName 4640 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4641 CurContext, Record->getLocation(), 4642 Record->getIdentifier(), 4643 Record->getTagKeywordLoc(), 4644 Record); 4645 InjectedClassName->setImplicit(); 4646 InjectedClassName->setAccess(AS_public); 4647 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4648 InjectedClassName->setDescribedClassTemplate(Template); 4649 PushOnScopeChains(InjectedClassName, S); 4650 assert(InjectedClassName->isInjectedClassName() && 4651 "Broken injected-class-name"); 4652 } 4653 } 4654} 4655 4656void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4657 SourceLocation RBraceLoc) { 4658 AdjustDeclIfTemplate(TagD); 4659 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4660 Tag->setRBraceLoc(RBraceLoc); 4661 4662 if (isa<CXXRecordDecl>(Tag)) 4663 FieldCollector->FinishClass(); 4664 4665 // Exit this scope of this tag's definition. 4666 PopDeclContext(); 4667 4668 // Notify the consumer that we've defined a tag. 4669 Consumer.HandleTagDeclDefinition(Tag); 4670} 4671 4672// Note that FieldName may be null for anonymous bitfields. 4673bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4674 QualType FieldTy, const Expr *BitWidth, 4675 bool *ZeroWidth) { 4676 // Default to true; that shouldn't confuse checks for emptiness 4677 if (ZeroWidth) 4678 *ZeroWidth = true; 4679 4680 // C99 6.7.2.1p4 - verify the field type. 4681 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4682 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4683 // Handle incomplete types with specific error. 4684 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4685 return true; 4686 if (FieldName) 4687 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4688 << FieldName << FieldTy << BitWidth->getSourceRange(); 4689 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4690 << FieldTy << BitWidth->getSourceRange(); 4691 } 4692 4693 // If the bit-width is type- or value-dependent, don't try to check 4694 // it now. 4695 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4696 return false; 4697 4698 llvm::APSInt Value; 4699 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4700 return true; 4701 4702 if (Value != 0 && ZeroWidth) 4703 *ZeroWidth = false; 4704 4705 // Zero-width bitfield is ok for anonymous field. 4706 if (Value == 0 && FieldName) 4707 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4708 4709 if (Value.isSigned() && Value.isNegative()) { 4710 if (FieldName) 4711 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4712 << FieldName << Value.toString(10); 4713 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4714 << Value.toString(10); 4715 } 4716 4717 if (!FieldTy->isDependentType()) { 4718 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4719 if (Value.getZExtValue() > TypeSize) { 4720 if (FieldName) 4721 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4722 << FieldName << (unsigned)TypeSize; 4723 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4724 << (unsigned)TypeSize; 4725 } 4726 } 4727 4728 return false; 4729} 4730 4731/// ActOnField - Each field of a struct/union/class is passed into this in order 4732/// to create a FieldDecl object for it. 4733Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4734 SourceLocation DeclStart, 4735 Declarator &D, ExprTy *BitfieldWidth) { 4736 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4737 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4738 AS_public); 4739 return DeclPtrTy::make(Res); 4740} 4741 4742/// HandleField - Analyze a field of a C struct or a C++ data member. 4743/// 4744FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4745 SourceLocation DeclStart, 4746 Declarator &D, Expr *BitWidth, 4747 AccessSpecifier AS) { 4748 IdentifierInfo *II = D.getIdentifier(); 4749 SourceLocation Loc = DeclStart; 4750 if (II) Loc = D.getIdentifierLoc(); 4751 4752 DeclaratorInfo *DInfo = 0; 4753 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4754 if (getLangOptions().CPlusPlus) 4755 CheckExtraCXXDefaultArguments(D); 4756 4757 DiagnoseFunctionSpecifiers(D); 4758 4759 if (D.getDeclSpec().isThreadSpecified()) 4760 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4761 4762 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4763 4764 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4765 // Maybe we will complain about the shadowed template parameter. 4766 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4767 // Just pretend that we didn't see the previous declaration. 4768 PrevDecl = 0; 4769 } 4770 4771 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4772 PrevDecl = 0; 4773 4774 bool Mutable 4775 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4776 SourceLocation TSSL = D.getSourceRange().getBegin(); 4777 FieldDecl *NewFD 4778 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4779 AS, PrevDecl, &D); 4780 if (NewFD->isInvalidDecl() && PrevDecl) { 4781 // Don't introduce NewFD into scope; there's already something 4782 // with the same name in the same scope. 4783 } else if (II) { 4784 PushOnScopeChains(NewFD, S); 4785 } else 4786 Record->addDecl(NewFD); 4787 4788 return NewFD; 4789} 4790 4791/// \brief Build a new FieldDecl and check its well-formedness. 4792/// 4793/// This routine builds a new FieldDecl given the fields name, type, 4794/// record, etc. \p PrevDecl should refer to any previous declaration 4795/// with the same name and in the same scope as the field to be 4796/// created. 4797/// 4798/// \returns a new FieldDecl. 4799/// 4800/// \todo The Declarator argument is a hack. It will be removed once 4801FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4802 DeclaratorInfo *DInfo, 4803 RecordDecl *Record, SourceLocation Loc, 4804 bool Mutable, Expr *BitWidth, 4805 SourceLocation TSSL, 4806 AccessSpecifier AS, NamedDecl *PrevDecl, 4807 Declarator *D) { 4808 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4809 bool InvalidDecl = false; 4810 if (D) InvalidDecl = D->isInvalidType(); 4811 4812 // If we receive a broken type, recover by assuming 'int' and 4813 // marking this declaration as invalid. 4814 if (T.isNull()) { 4815 InvalidDecl = true; 4816 T = Context.IntTy; 4817 } 4818 4819 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4820 // than a variably modified type. 4821 if (T->isVariablyModifiedType()) { 4822 bool SizeIsNegative; 4823 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4824 SizeIsNegative); 4825 if (!FixedTy.isNull()) { 4826 Diag(Loc, diag::warn_illegal_constant_array_size); 4827 T = FixedTy; 4828 } else { 4829 if (SizeIsNegative) 4830 Diag(Loc, diag::err_typecheck_negative_array_size); 4831 else 4832 Diag(Loc, diag::err_typecheck_field_variable_size); 4833 InvalidDecl = true; 4834 } 4835 } 4836 4837 // Fields can not have abstract class types 4838 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4839 AbstractFieldType)) 4840 InvalidDecl = true; 4841 4842 bool ZeroWidth = false; 4843 // If this is declared as a bit-field, check the bit-field. 4844 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4845 InvalidDecl = true; 4846 DeleteExpr(BitWidth); 4847 BitWidth = 0; 4848 ZeroWidth = false; 4849 } 4850 4851 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4852 BitWidth, Mutable); 4853 if (InvalidDecl) 4854 NewFD->setInvalidDecl(); 4855 4856 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4857 Diag(Loc, diag::err_duplicate_member) << II; 4858 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4859 NewFD->setInvalidDecl(); 4860 } 4861 4862 if (getLangOptions().CPlusPlus) { 4863 QualType EltTy = Context.getBaseElementType(T); 4864 4865 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4866 4867 if (!T->isPODType()) 4868 CXXRecord->setPOD(false); 4869 if (!ZeroWidth) 4870 CXXRecord->setEmpty(false); 4871 4872 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4873 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4874 4875 if (!RDecl->hasTrivialConstructor()) 4876 CXXRecord->setHasTrivialConstructor(false); 4877 if (!RDecl->hasTrivialCopyConstructor()) 4878 CXXRecord->setHasTrivialCopyConstructor(false); 4879 if (!RDecl->hasTrivialCopyAssignment()) 4880 CXXRecord->setHasTrivialCopyAssignment(false); 4881 if (!RDecl->hasTrivialDestructor()) 4882 CXXRecord->setHasTrivialDestructor(false); 4883 4884 // C++ 9.5p1: An object of a class with a non-trivial 4885 // constructor, a non-trivial copy constructor, a non-trivial 4886 // destructor, or a non-trivial copy assignment operator 4887 // cannot be a member of a union, nor can an array of such 4888 // objects. 4889 // TODO: C++0x alters this restriction significantly. 4890 if (Record->isUnion()) { 4891 // We check for copy constructors before constructors 4892 // because otherwise we'll never get complaints about 4893 // copy constructors. 4894 4895 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4896 4897 CXXSpecialMember member; 4898 if (!RDecl->hasTrivialCopyConstructor()) 4899 member = CXXCopyConstructor; 4900 else if (!RDecl->hasTrivialConstructor()) 4901 member = CXXDefaultConstructor; 4902 else if (!RDecl->hasTrivialCopyAssignment()) 4903 member = CXXCopyAssignment; 4904 else if (!RDecl->hasTrivialDestructor()) 4905 member = CXXDestructor; 4906 else 4907 member = invalid; 4908 4909 if (member != invalid) { 4910 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4911 DiagnoseNontrivial(RT, member); 4912 NewFD->setInvalidDecl(); 4913 } 4914 } 4915 } 4916 } 4917 4918 // FIXME: We need to pass in the attributes given an AST 4919 // representation, not a parser representation. 4920 if (D) 4921 // FIXME: What to pass instead of TUScope? 4922 ProcessDeclAttributes(TUScope, NewFD, *D); 4923 4924 if (T.isObjCGCWeak()) 4925 Diag(Loc, diag::warn_attribute_weak_on_field); 4926 4927 NewFD->setAccess(AS); 4928 4929 // C++ [dcl.init.aggr]p1: 4930 // An aggregate is an array or a class (clause 9) with [...] no 4931 // private or protected non-static data members (clause 11). 4932 // A POD must be an aggregate. 4933 if (getLangOptions().CPlusPlus && 4934 (AS == AS_private || AS == AS_protected)) { 4935 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4936 CXXRecord->setAggregate(false); 4937 CXXRecord->setPOD(false); 4938 } 4939 4940 return NewFD; 4941} 4942 4943/// DiagnoseNontrivial - Given that a class has a non-trivial 4944/// special member, figure out why. 4945void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4946 QualType QT(T, 0U); 4947 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4948 4949 // Check whether the member was user-declared. 4950 switch (member) { 4951 case CXXDefaultConstructor: 4952 if (RD->hasUserDeclaredConstructor()) { 4953 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4954 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4955 if (!ci->isImplicitlyDefined(Context)) { 4956 SourceLocation CtorLoc = ci->getLocation(); 4957 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4958 return; 4959 } 4960 4961 assert(0 && "found no user-declared constructors"); 4962 return; 4963 } 4964 break; 4965 4966 case CXXCopyConstructor: 4967 if (RD->hasUserDeclaredCopyConstructor()) { 4968 SourceLocation CtorLoc = 4969 RD->getCopyConstructor(Context, 0)->getLocation(); 4970 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4971 return; 4972 } 4973 break; 4974 4975 case CXXCopyAssignment: 4976 if (RD->hasUserDeclaredCopyAssignment()) { 4977 // FIXME: this should use the location of the copy 4978 // assignment, not the type. 4979 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4980 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4981 return; 4982 } 4983 break; 4984 4985 case CXXDestructor: 4986 if (RD->hasUserDeclaredDestructor()) { 4987 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4988 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4989 return; 4990 } 4991 break; 4992 } 4993 4994 typedef CXXRecordDecl::base_class_iterator base_iter; 4995 4996 // Virtual bases and members inhibit trivial copying/construction, 4997 // but not trivial destruction. 4998 if (member != CXXDestructor) { 4999 // Check for virtual bases. vbases includes indirect virtual bases, 5000 // so we just iterate through the direct bases. 5001 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5002 if (bi->isVirtual()) { 5003 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5004 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5005 return; 5006 } 5007 5008 // Check for virtual methods. 5009 typedef CXXRecordDecl::method_iterator meth_iter; 5010 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5011 ++mi) { 5012 if (mi->isVirtual()) { 5013 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5014 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5015 return; 5016 } 5017 } 5018 } 5019 5020 bool (CXXRecordDecl::*hasTrivial)() const; 5021 switch (member) { 5022 case CXXDefaultConstructor: 5023 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5024 case CXXCopyConstructor: 5025 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5026 case CXXCopyAssignment: 5027 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5028 case CXXDestructor: 5029 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5030 default: 5031 assert(0 && "unexpected special member"); return; 5032 } 5033 5034 // Check for nontrivial bases (and recurse). 5035 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5036 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5037 assert(BaseRT); 5038 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5039 if (!(BaseRecTy->*hasTrivial)()) { 5040 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5041 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5042 DiagnoseNontrivial(BaseRT, member); 5043 return; 5044 } 5045 } 5046 5047 // Check for nontrivial members (and recurse). 5048 typedef RecordDecl::field_iterator field_iter; 5049 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5050 ++fi) { 5051 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5052 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5053 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5054 5055 if (!(EltRD->*hasTrivial)()) { 5056 SourceLocation FLoc = (*fi)->getLocation(); 5057 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5058 DiagnoseNontrivial(EltRT, member); 5059 return; 5060 } 5061 } 5062 } 5063 5064 assert(0 && "found no explanation for non-trivial member"); 5065} 5066 5067/// TranslateIvarVisibility - Translate visibility from a token ID to an 5068/// AST enum value. 5069static ObjCIvarDecl::AccessControl 5070TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5071 switch (ivarVisibility) { 5072 default: assert(0 && "Unknown visitibility kind"); 5073 case tok::objc_private: return ObjCIvarDecl::Private; 5074 case tok::objc_public: return ObjCIvarDecl::Public; 5075 case tok::objc_protected: return ObjCIvarDecl::Protected; 5076 case tok::objc_package: return ObjCIvarDecl::Package; 5077 } 5078} 5079 5080/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5081/// in order to create an IvarDecl object for it. 5082Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5083 SourceLocation DeclStart, 5084 DeclPtrTy IntfDecl, 5085 Declarator &D, ExprTy *BitfieldWidth, 5086 tok::ObjCKeywordKind Visibility) { 5087 5088 IdentifierInfo *II = D.getIdentifier(); 5089 Expr *BitWidth = (Expr*)BitfieldWidth; 5090 SourceLocation Loc = DeclStart; 5091 if (II) Loc = D.getIdentifierLoc(); 5092 5093 // FIXME: Unnamed fields can be handled in various different ways, for 5094 // example, unnamed unions inject all members into the struct namespace! 5095 5096 DeclaratorInfo *DInfo = 0; 5097 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5098 5099 if (BitWidth) { 5100 // 6.7.2.1p3, 6.7.2.1p4 5101 if (VerifyBitField(Loc, II, T, BitWidth)) { 5102 D.setInvalidType(); 5103 DeleteExpr(BitWidth); 5104 BitWidth = 0; 5105 } 5106 } else { 5107 // Not a bitfield. 5108 5109 // validate II. 5110 5111 } 5112 5113 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5114 // than a variably modified type. 5115 if (T->isVariablyModifiedType()) { 5116 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5117 D.setInvalidType(); 5118 } 5119 5120 // Get the visibility (access control) for this ivar. 5121 ObjCIvarDecl::AccessControl ac = 5122 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5123 : ObjCIvarDecl::None; 5124 // Must set ivar's DeclContext to its enclosing interface. 5125 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5126 DeclContext *EnclosingContext; 5127 if (ObjCImplementationDecl *IMPDecl = 5128 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5129 // Case of ivar declared in an implementation. Context is that of its class. 5130 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5131 assert(IDecl && "No class- ActOnIvar"); 5132 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5133 } else 5134 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5135 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5136 5137 // Construct the decl. 5138 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5139 EnclosingContext, Loc, II, T, 5140 DInfo, ac, (Expr *)BitfieldWidth); 5141 5142 if (II) { 5143 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5144 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5145 && !isa<TagDecl>(PrevDecl)) { 5146 Diag(Loc, diag::err_duplicate_member) << II; 5147 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5148 NewID->setInvalidDecl(); 5149 } 5150 } 5151 5152 // Process attributes attached to the ivar. 5153 ProcessDeclAttributes(S, NewID, D); 5154 5155 if (D.isInvalidType()) 5156 NewID->setInvalidDecl(); 5157 5158 if (II) { 5159 // FIXME: When interfaces are DeclContexts, we'll need to add 5160 // these to the interface. 5161 S->AddDecl(DeclPtrTy::make(NewID)); 5162 IdResolver.AddDecl(NewID); 5163 } 5164 5165 return DeclPtrTy::make(NewID); 5166} 5167 5168void Sema::ActOnFields(Scope* S, 5169 SourceLocation RecLoc, DeclPtrTy RecDecl, 5170 DeclPtrTy *Fields, unsigned NumFields, 5171 SourceLocation LBrac, SourceLocation RBrac, 5172 AttributeList *Attr) { 5173 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5174 assert(EnclosingDecl && "missing record or interface decl"); 5175 5176 // If the decl this is being inserted into is invalid, then it may be a 5177 // redeclaration or some other bogus case. Don't try to add fields to it. 5178 if (EnclosingDecl->isInvalidDecl()) { 5179 // FIXME: Deallocate fields? 5180 return; 5181 } 5182 5183 5184 // Verify that all the fields are okay. 5185 unsigned NumNamedMembers = 0; 5186 llvm::SmallVector<FieldDecl*, 32> RecFields; 5187 5188 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5189 for (unsigned i = 0; i != NumFields; ++i) { 5190 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5191 5192 // Get the type for the field. 5193 Type *FDTy = FD->getType().getTypePtr(); 5194 5195 if (!FD->isAnonymousStructOrUnion()) { 5196 // Remember all fields written by the user. 5197 RecFields.push_back(FD); 5198 } 5199 5200 // If the field is already invalid for some reason, don't emit more 5201 // diagnostics about it. 5202 if (FD->isInvalidDecl()) 5203 continue; 5204 5205 // C99 6.7.2.1p2: 5206 // A structure or union shall not contain a member with 5207 // incomplete or function type (hence, a structure shall not 5208 // contain an instance of itself, but may contain a pointer to 5209 // an instance of itself), except that the last member of a 5210 // structure with more than one named member may have incomplete 5211 // array type; such a structure (and any union containing, 5212 // possibly recursively, a member that is such a structure) 5213 // shall not be a member of a structure or an element of an 5214 // array. 5215 if (FDTy->isFunctionType()) { 5216 // Field declared as a function. 5217 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5218 << FD->getDeclName(); 5219 FD->setInvalidDecl(); 5220 EnclosingDecl->setInvalidDecl(); 5221 continue; 5222 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5223 Record && Record->isStruct()) { 5224 // Flexible array member. 5225 if (NumNamedMembers < 1) { 5226 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5227 << FD->getDeclName(); 5228 FD->setInvalidDecl(); 5229 EnclosingDecl->setInvalidDecl(); 5230 continue; 5231 } 5232 // Okay, we have a legal flexible array member at the end of the struct. 5233 if (Record) 5234 Record->setHasFlexibleArrayMember(true); 5235 } else if (!FDTy->isDependentType() && 5236 RequireCompleteType(FD->getLocation(), FD->getType(), 5237 diag::err_field_incomplete)) { 5238 // Incomplete type 5239 FD->setInvalidDecl(); 5240 EnclosingDecl->setInvalidDecl(); 5241 continue; 5242 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5243 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5244 // If this is a member of a union, then entire union becomes "flexible". 5245 if (Record && Record->isUnion()) { 5246 Record->setHasFlexibleArrayMember(true); 5247 } else { 5248 // If this is a struct/class and this is not the last element, reject 5249 // it. Note that GCC supports variable sized arrays in the middle of 5250 // structures. 5251 if (i != NumFields-1) 5252 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5253 << FD->getDeclName() << FD->getType(); 5254 else { 5255 // We support flexible arrays at the end of structs in 5256 // other structs as an extension. 5257 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5258 << FD->getDeclName(); 5259 if (Record) 5260 Record->setHasFlexibleArrayMember(true); 5261 } 5262 } 5263 } 5264 if (Record && FDTTy->getDecl()->hasObjectMember()) 5265 Record->setHasObjectMember(true); 5266 } else if (FDTy->isObjCInterfaceType()) { 5267 /// A field cannot be an Objective-c object 5268 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5269 FD->setInvalidDecl(); 5270 EnclosingDecl->setInvalidDecl(); 5271 continue; 5272 } else if (getLangOptions().ObjC1 && 5273 getLangOptions().getGCMode() != LangOptions::NonGC && 5274 Record && 5275 (FD->getType()->isObjCObjectPointerType() || 5276 FD->getType().isObjCGCStrong())) 5277 Record->setHasObjectMember(true); 5278 // Keep track of the number of named members. 5279 if (FD->getIdentifier()) 5280 ++NumNamedMembers; 5281 } 5282 5283 // Okay, we successfully defined 'Record'. 5284 if (Record) { 5285 Record->completeDefinition(Context); 5286 } else { 5287 ObjCIvarDecl **ClsFields = 5288 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5289 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5290 ID->setIVarList(ClsFields, RecFields.size(), Context); 5291 ID->setLocEnd(RBrac); 5292 // Add ivar's to class's DeclContext. 5293 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5294 ClsFields[i]->setLexicalDeclContext(ID); 5295 ID->addDecl(ClsFields[i]); 5296 } 5297 // Must enforce the rule that ivars in the base classes may not be 5298 // duplicates. 5299 if (ID->getSuperClass()) { 5300 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5301 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5302 ObjCIvarDecl* Ivar = (*IVI); 5303 5304 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5305 ObjCIvarDecl* prevIvar = 5306 ID->getSuperClass()->lookupInstanceVariable(II); 5307 if (prevIvar) { 5308 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5309 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5310 } 5311 } 5312 } 5313 } 5314 } else if (ObjCImplementationDecl *IMPDecl = 5315 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5316 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5317 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5318 // Ivar declared in @implementation never belongs to the implementation. 5319 // Only it is in implementation's lexical context. 5320 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5321 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5322 } 5323 } 5324 5325 if (Attr) 5326 ProcessDeclAttributeList(S, Record, Attr); 5327} 5328 5329EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5330 EnumConstantDecl *LastEnumConst, 5331 SourceLocation IdLoc, 5332 IdentifierInfo *Id, 5333 ExprArg val) { 5334 Expr *Val = (Expr *)val.get(); 5335 5336 llvm::APSInt EnumVal(32); 5337 QualType EltTy; 5338 if (Val && !Val->isTypeDependent()) { 5339 // Make sure to promote the operand type to int. 5340 UsualUnaryConversions(Val); 5341 if (Val != val.get()) { 5342 val.release(); 5343 val = Val; 5344 } 5345 5346 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5347 SourceLocation ExpLoc; 5348 if (!Val->isValueDependent() && 5349 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5350 Val = 0; 5351 } else { 5352 EltTy = Val->getType(); 5353 } 5354 } 5355 5356 if (!Val) { 5357 if (LastEnumConst) { 5358 // Assign the last value + 1. 5359 EnumVal = LastEnumConst->getInitVal(); 5360 ++EnumVal; 5361 5362 // Check for overflow on increment. 5363 if (EnumVal < LastEnumConst->getInitVal()) 5364 Diag(IdLoc, diag::warn_enum_value_overflow); 5365 5366 EltTy = LastEnumConst->getType(); 5367 } else { 5368 // First value, set to zero. 5369 EltTy = Context.IntTy; 5370 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5371 } 5372 } 5373 5374 val.release(); 5375 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5376 Val, EnumVal); 5377} 5378 5379 5380Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5381 DeclPtrTy lastEnumConst, 5382 SourceLocation IdLoc, 5383 IdentifierInfo *Id, 5384 SourceLocation EqualLoc, ExprTy *val) { 5385 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5386 EnumConstantDecl *LastEnumConst = 5387 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5388 Expr *Val = static_cast<Expr*>(val); 5389 5390 // The scope passed in may not be a decl scope. Zip up the scope tree until 5391 // we find one that is. 5392 S = getNonFieldDeclScope(S); 5393 5394 // Verify that there isn't already something declared with this name in this 5395 // scope. 5396 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5397 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5398 // Maybe we will complain about the shadowed template parameter. 5399 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5400 // Just pretend that we didn't see the previous declaration. 5401 PrevDecl = 0; 5402 } 5403 5404 if (PrevDecl) { 5405 // When in C++, we may get a TagDecl with the same name; in this case the 5406 // enum constant will 'hide' the tag. 5407 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5408 "Received TagDecl when not in C++!"); 5409 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5410 if (isa<EnumConstantDecl>(PrevDecl)) 5411 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5412 else 5413 Diag(IdLoc, diag::err_redefinition) << Id; 5414 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5415 if (Val) Val->Destroy(Context); 5416 return DeclPtrTy(); 5417 } 5418 } 5419 5420 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5421 IdLoc, Id, Owned(Val)); 5422 5423 // Register this decl in the current scope stack. 5424 if (New) 5425 PushOnScopeChains(New, S); 5426 5427 return DeclPtrTy::make(New); 5428} 5429 5430void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5431 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5432 DeclPtrTy *Elements, unsigned NumElements, 5433 Scope *S, AttributeList *Attr) { 5434 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5435 QualType EnumType = Context.getTypeDeclType(Enum); 5436 5437 if (Attr) 5438 ProcessDeclAttributeList(S, Enum, Attr); 5439 5440 // TODO: If the result value doesn't fit in an int, it must be a long or long 5441 // long value. ISO C does not support this, but GCC does as an extension, 5442 // emit a warning. 5443 unsigned IntWidth = Context.Target.getIntWidth(); 5444 unsigned CharWidth = Context.Target.getCharWidth(); 5445 unsigned ShortWidth = Context.Target.getShortWidth(); 5446 5447 // Verify that all the values are okay, compute the size of the values, and 5448 // reverse the list. 5449 unsigned NumNegativeBits = 0; 5450 unsigned NumPositiveBits = 0; 5451 5452 // Keep track of whether all elements have type int. 5453 bool AllElementsInt = true; 5454 5455 for (unsigned i = 0; i != NumElements; ++i) { 5456 EnumConstantDecl *ECD = 5457 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5458 if (!ECD) continue; // Already issued a diagnostic. 5459 5460 // If the enum value doesn't fit in an int, emit an extension warning. 5461 const llvm::APSInt &InitVal = ECD->getInitVal(); 5462 assert(InitVal.getBitWidth() >= IntWidth && 5463 "Should have promoted value to int"); 5464 if (InitVal.getBitWidth() > IntWidth) { 5465 llvm::APSInt V(InitVal); 5466 V.trunc(IntWidth); 5467 V.extend(InitVal.getBitWidth()); 5468 if (V != InitVal) 5469 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5470 << InitVal.toString(10); 5471 } 5472 5473 // Keep track of the size of positive and negative values. 5474 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5475 NumPositiveBits = std::max(NumPositiveBits, 5476 (unsigned)InitVal.getActiveBits()); 5477 else 5478 NumNegativeBits = std::max(NumNegativeBits, 5479 (unsigned)InitVal.getMinSignedBits()); 5480 5481 // Keep track of whether every enum element has type int (very commmon). 5482 if (AllElementsInt) 5483 AllElementsInt = ECD->getType() == Context.IntTy; 5484 } 5485 5486 // Figure out the type that should be used for this enum. 5487 // FIXME: Support -fshort-enums. 5488 QualType BestType; 5489 unsigned BestWidth; 5490 5491 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5492 5493 if (NumNegativeBits) { 5494 // If there is a negative value, figure out the smallest integer type (of 5495 // int/long/longlong) that fits. 5496 // If it's packed, check also if it fits a char or a short. 5497 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5498 BestType = Context.SignedCharTy; 5499 BestWidth = CharWidth; 5500 } else if (Packed && NumNegativeBits <= ShortWidth && 5501 NumPositiveBits < ShortWidth) { 5502 BestType = Context.ShortTy; 5503 BestWidth = ShortWidth; 5504 } 5505 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5506 BestType = Context.IntTy; 5507 BestWidth = IntWidth; 5508 } else { 5509 BestWidth = Context.Target.getLongWidth(); 5510 5511 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5512 BestType = Context.LongTy; 5513 else { 5514 BestWidth = Context.Target.getLongLongWidth(); 5515 5516 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5517 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5518 BestType = Context.LongLongTy; 5519 } 5520 } 5521 } else { 5522 // If there is no negative value, figure out which of uint, ulong, ulonglong 5523 // fits. 5524 // If it's packed, check also if it fits a char or a short. 5525 if (Packed && NumPositiveBits <= CharWidth) { 5526 BestType = Context.UnsignedCharTy; 5527 BestWidth = CharWidth; 5528 } else if (Packed && NumPositiveBits <= ShortWidth) { 5529 BestType = Context.UnsignedShortTy; 5530 BestWidth = ShortWidth; 5531 } 5532 else if (NumPositiveBits <= IntWidth) { 5533 BestType = Context.UnsignedIntTy; 5534 BestWidth = IntWidth; 5535 } else if (NumPositiveBits <= 5536 (BestWidth = Context.Target.getLongWidth())) { 5537 BestType = Context.UnsignedLongTy; 5538 } else { 5539 BestWidth = Context.Target.getLongLongWidth(); 5540 assert(NumPositiveBits <= BestWidth && 5541 "How could an initializer get larger than ULL?"); 5542 BestType = Context.UnsignedLongLongTy; 5543 } 5544 } 5545 5546 // Loop over all of the enumerator constants, changing their types to match 5547 // the type of the enum if needed. 5548 for (unsigned i = 0; i != NumElements; ++i) { 5549 EnumConstantDecl *ECD = 5550 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5551 if (!ECD) continue; // Already issued a diagnostic. 5552 5553 // Standard C says the enumerators have int type, but we allow, as an 5554 // extension, the enumerators to be larger than int size. If each 5555 // enumerator value fits in an int, type it as an int, otherwise type it the 5556 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5557 // that X has type 'int', not 'unsigned'. 5558 if (ECD->getType() == Context.IntTy) { 5559 // Make sure the init value is signed. 5560 llvm::APSInt IV = ECD->getInitVal(); 5561 IV.setIsSigned(true); 5562 ECD->setInitVal(IV); 5563 5564 if (getLangOptions().CPlusPlus) 5565 // C++ [dcl.enum]p4: Following the closing brace of an 5566 // enum-specifier, each enumerator has the type of its 5567 // enumeration. 5568 ECD->setType(EnumType); 5569 continue; // Already int type. 5570 } 5571 5572 // Determine whether the value fits into an int. 5573 llvm::APSInt InitVal = ECD->getInitVal(); 5574 bool FitsInInt; 5575 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5576 FitsInInt = InitVal.getActiveBits() < IntWidth; 5577 else 5578 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5579 5580 // If it fits into an integer type, force it. Otherwise force it to match 5581 // the enum decl type. 5582 QualType NewTy; 5583 unsigned NewWidth; 5584 bool NewSign; 5585 if (FitsInInt) { 5586 NewTy = Context.IntTy; 5587 NewWidth = IntWidth; 5588 NewSign = true; 5589 } else if (ECD->getType() == BestType) { 5590 // Already the right type! 5591 if (getLangOptions().CPlusPlus) 5592 // C++ [dcl.enum]p4: Following the closing brace of an 5593 // enum-specifier, each enumerator has the type of its 5594 // enumeration. 5595 ECD->setType(EnumType); 5596 continue; 5597 } else { 5598 NewTy = BestType; 5599 NewWidth = BestWidth; 5600 NewSign = BestType->isSignedIntegerType(); 5601 } 5602 5603 // Adjust the APSInt value. 5604 InitVal.extOrTrunc(NewWidth); 5605 InitVal.setIsSigned(NewSign); 5606 ECD->setInitVal(InitVal); 5607 5608 // Adjust the Expr initializer and type. 5609 if (ECD->getInitExpr()) 5610 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5611 CastExpr::CK_IntegralCast, 5612 ECD->getInitExpr(), 5613 /*isLvalue=*/false)); 5614 if (getLangOptions().CPlusPlus) 5615 // C++ [dcl.enum]p4: Following the closing brace of an 5616 // enum-specifier, each enumerator has the type of its 5617 // enumeration. 5618 ECD->setType(EnumType); 5619 else 5620 ECD->setType(NewTy); 5621 } 5622 5623 Enum->completeDefinition(Context, BestType); 5624} 5625 5626Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5627 ExprArg expr) { 5628 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5629 5630 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5631 Loc, AsmString); 5632 CurContext->addDecl(New); 5633 return DeclPtrTy::make(New); 5634} 5635 5636void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5637 SourceLocation PragmaLoc, 5638 SourceLocation NameLoc) { 5639 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5640 5641 if (PrevDecl) { 5642 PrevDecl->addAttr(::new (Context) WeakAttr()); 5643 } else { 5644 (void)WeakUndeclaredIdentifiers.insert( 5645 std::pair<IdentifierInfo*,WeakInfo> 5646 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5647 } 5648} 5649 5650void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5651 IdentifierInfo* AliasName, 5652 SourceLocation PragmaLoc, 5653 SourceLocation NameLoc, 5654 SourceLocation AliasNameLoc) { 5655 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5656 WeakInfo W = WeakInfo(Name, NameLoc); 5657 5658 if (PrevDecl) { 5659 if (!PrevDecl->hasAttr<AliasAttr>()) 5660 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5661 DeclApplyPragmaWeak(TUScope, ND, W); 5662 } else { 5663 (void)WeakUndeclaredIdentifiers.insert( 5664 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5665 } 5666} 5667